From b78adf1d9502a4e206b13f7348370eb483a5edcc Mon Sep 17 00:00:00 2001
From: Alexander Miroshnichenko <alex@millerson.name>
Date: Thu, 27 Mar 2025 14:52:55 +0300
Subject: [PATCH] bcachefs: cherry-pick updates from master 4594600
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 8bit

Signed-off-by: Alexander Miroshnichenko <alex@millerson.name>
---
 .../bcachefs/SubmittingPatches.rst            |  43 +-
 .../filesystems/bcachefs/casefolding.rst      |  90 ++
 Documentation/filesystems/bcachefs/index.rst  |  20 +-
 block/blk-core.c                              |  19 +-
 fs/bcachefs/Kconfig                           |   2 +-
 fs/bcachefs/Makefile                          |   3 +-
 fs/bcachefs/alloc_background.c                | 190 ++--
 fs/bcachefs/alloc_background.h                |   2 +-
 fs/bcachefs/alloc_foreground.c                |  31 +-
 fs/bcachefs/alloc_foreground.h                |  19 +-
 fs/bcachefs/alloc_types.h                     |   2 +
 fs/bcachefs/backpointers.c                    | 151 ++-
 fs/bcachefs/backpointers.h                    |  26 +-
 fs/bcachefs/bcachefs.h                        |  20 +-
 fs/bcachefs/bcachefs_format.h                 |  16 +-
 fs/bcachefs/bcachefs_ioctl.h                  |  29 +-
 fs/bcachefs/bkey.h                            |   1 +
 fs/bcachefs/btree_cache.c                     |   1 +
 fs/bcachefs/btree_gc.c                        |  18 +-
 fs/bcachefs/btree_io.c                        | 259 +++++-
 fs/bcachefs/btree_io.h                        |   4 +
 fs/bcachefs/btree_iter.c                      |  14 -
 fs/bcachefs/btree_iter.h                      |   9 +-
 fs/bcachefs/btree_locking.c                   |   8 +-
 fs/bcachefs/btree_node_scan.c                 |  29 +-
 fs/bcachefs/btree_trans_commit.c              | 120 +--
 fs/bcachefs/btree_types.h                     |  13 +
 fs/bcachefs/btree_update.c                    |   5 +-
 fs/bcachefs/btree_update.h                    |   2 +
 fs/bcachefs/btree_update_interior.c           | 150 +--
 fs/bcachefs/btree_update_interior.h           |   7 +
 fs/bcachefs/buckets.c                         |  80 +-
 fs/bcachefs/buckets.h                         |  31 +-
 fs/bcachefs/buckets_types.h                   |  27 +
 fs/bcachefs/chardev.c                         |  38 +-
 fs/bcachefs/checksum.c                        |  25 +-
 fs/bcachefs/checksum.h                        |   2 +
 fs/bcachefs/compress.c                        |  65 +-
 fs/bcachefs/data_update.c                     | 237 +++--
 fs/bcachefs/data_update.h                     |  17 +-
 fs/bcachefs/debug.c                           |  34 +-
 fs/bcachefs/dirent.c                          | 274 +++++-
 fs/bcachefs/dirent.h                          |  17 +-
 fs/bcachefs/dirent_format.h                   |  20 +-
 fs/bcachefs/disk_accounting.c                 |  11 +
 fs/bcachefs/disk_accounting.h                 |  26 +-
 fs/bcachefs/disk_accounting_format.h          |  90 +-
 fs/bcachefs/ec.c                              | 482 ++++------
 fs/bcachefs/ec.h                              |  46 +-
 fs/bcachefs/ec_types.h                        |  12 +-
 fs/bcachefs/errcode.h                         |  65 +-
 fs/bcachefs/error.c                           |  88 +-
 fs/bcachefs/error.h                           |  57 +-
 fs/bcachefs/extents.c                         | 245 +++--
 fs/bcachefs/extents.h                         |  24 +-
 fs/bcachefs/extents_format.h                  |  24 +-
 fs/bcachefs/extents_types.h                   |  11 +-
 fs/bcachefs/eytzinger.c                       |  76 +-
 fs/bcachefs/eytzinger.h                       |  95 +-
 fs/bcachefs/fs-io-buffered.c                  |  40 +-
 fs/bcachefs/fs-io-direct.c                    |  20 +-
 fs/bcachefs/fs-ioctl.c                        |  30 +-
 fs/bcachefs/fs-ioctl.h                        |  20 +-
 fs/bcachefs/fs.c                              | 139 +--
 fs/bcachefs/fsck.c                            | 231 +----
 fs/bcachefs/inode.c                           |  24 +-
 fs/bcachefs/inode.h                           |   1 +
 fs/bcachefs/inode_format.h                    |   3 +-
 fs/bcachefs/io_misc.c                         |   3 +-
 fs/bcachefs/io_read.c                         | 856 +++++++++++-------
 fs/bcachefs/io_read.h                         |  97 +-
 fs/bcachefs/io_write.c                        | 438 ++++-----
 fs/bcachefs/io_write.h                        |  38 +-
 fs/bcachefs/io_write_types.h                  |   2 +-
 fs/bcachefs/journal.c                         | 202 +++--
 fs/bcachefs/journal.h                         |  42 +-
 fs/bcachefs/journal_io.c                      |  99 +-
 fs/bcachefs/journal_reclaim.c                 |  10 +-
 fs/bcachefs/journal_seq_blacklist.c           |   7 +-
 fs/bcachefs/journal_types.h                   |  37 +-
 fs/bcachefs/lru.c                             | 100 +-
 fs/bcachefs/lru.h                             |  22 +-
 fs/bcachefs/lru_format.h                      |   6 +-
 fs/bcachefs/migrate.c                         |  26 +-
 fs/bcachefs/move.c                            | 505 +++++++----
 fs/bcachefs/move_types.h                      |  20 +-
 fs/bcachefs/movinggc.c                        |  15 +-
 fs/bcachefs/{fs-common.c => namei.c}          | 210 ++++-
 fs/bcachefs/{fs-common.h => namei.h}          |  31 +-
 fs/bcachefs/opts.c                            | 117 ++-
 fs/bcachefs/opts.h                            |  70 +-
 fs/bcachefs/progress.c                        |  63 ++
 fs/bcachefs/progress.h                        |  29 +
 fs/bcachefs/rebalance.c                       |  52 +-
 fs/bcachefs/recovery.c                        |   4 +-
 fs/bcachefs/recovery_passes_types.h           |   2 +-
 fs/bcachefs/reflink.c                         |  23 +-
 fs/bcachefs/sb-counters.c                     |  90 +-
 fs/bcachefs/sb-counters.h                     |   4 +
 fs/bcachefs/sb-counters_format.h              |  32 +-
 fs/bcachefs/sb-downgrade.c                    |   8 +-
 fs/bcachefs/sb-errors_format.h                |   6 +-
 fs/bcachefs/sb-members.h                      |  16 +-
 fs/bcachefs/sb-members_format.h               |   1 +
 fs/bcachefs/snapshot.c                        |   7 +-
 fs/bcachefs/snapshot.h                        |   1 +
 fs/bcachefs/str_hash.c                        |   2 +-
 fs/bcachefs/str_hash.h                        |  12 +-
 fs/bcachefs/super-io.c                        |  92 +-
 fs/bcachefs/super-io.h                        |  10 +-
 fs/bcachefs/super.c                           | 141 ++-
 fs/bcachefs/super.h                           |   2 +
 fs/bcachefs/super_types.h                     |   8 +-
 fs/bcachefs/sysfs.c                           | 257 ++++--
 fs/bcachefs/sysfs.h                           |   5 +-
 fs/bcachefs/time_stats.c                      |  22 +-
 fs/bcachefs/time_stats.h                      |   1 +
 fs/bcachefs/trace.h                           | 106 +--
 fs/bcachefs/util.c                            | 231 ++++-
 fs/bcachefs/util.h                            |  16 +-
 fs/bcachefs/xattr.c                           |   2 +-
 121 files changed, 5238 insertions(+), 2990 deletions(-)
 create mode 100644 Documentation/filesystems/bcachefs/casefolding.rst
 rename fs/bcachefs/{fs-common.c => namei.c} (73%)
 rename fs/bcachefs/{fs-common.h => namei.h} (61%)
 create mode 100644 fs/bcachefs/progress.c
 create mode 100644 fs/bcachefs/progress.h

diff --git a/Documentation/filesystems/bcachefs/SubmittingPatches.rst b/Documentation/filesystems/bcachefs/SubmittingPatches.rst
index 026b12ae0d6a..a455f9cfd15c 100644
--- a/Documentation/filesystems/bcachefs/SubmittingPatches.rst
+++ b/Documentation/filesystems/bcachefs/SubmittingPatches.rst
@@ -1,8 +1,13 @@
-Submitting patches to bcachefs:
-===============================
+Submitting patches to bcachefs
+==============================
+
+Here are suggestions for submitting patches to bcachefs subsystem.
+
+Submission checklist
+--------------------
 
 Patches must be tested before being submitted, either with the xfstests suite
-[0], or the full bcachefs test suite in ktest [1], depending on what's being
+[0]_, or the full bcachefs test suite in ktest [1]_, depending on what's being
 touched. Note that ktest wraps xfstests and will be an easier method to running
 it for most users; it includes single-command wrappers for all the mainstream
 in-kernel local filesystems.
@@ -26,21 +31,21 @@ considered out of date), but try not to deviate too much without reason.
 Focus on writing code that reads well and is organized well; code should be
 aesthetically pleasing.
 
-CI:
-===
+CI
+--
 
 Instead of running your tests locally, when running the full test suite it's
 prefereable to let a server farm do it in parallel, and then have the results
 in a nice test dashboard (which can tell you which failures are new, and
 presents results in a git log view, avoiding the need for most bisecting).
 
-That exists [2], and community members may request an account. If you work for
+That exists [2]_, and community members may request an account. If you work for
 a big tech company, you'll need to help out with server costs to get access -
 but the CI is not restricted to running bcachefs tests: it runs any ktest test
 (which generally makes it easy to wrap other tests that can run in qemu).
 
-Other things to think about:
-============================
+Other things to think about
+---------------------------
 
 - How will we debug this code? Is there sufficient introspection to diagnose
   when something starts acting wonky on a user machine?
@@ -79,20 +84,22 @@ Other things to think about:
   tested? (Automated tests exists but aren't in the CI, due to the hassle of
   disk image management; coordinate to have them run.)
 
-Mailing list, IRC:
-==================
+Mailing list, IRC
+-----------------
 
-Patches should hit the list [3], but much discussion and code review happens on
-IRC as well [4]; many people appreciate the more conversational approach and
-quicker feedback.
+Patches should hit the list [3]_, but much discussion and code review happens
+on IRC as well [4]_; many people appreciate the more conversational approach
+and quicker feedback.
 
 Additionally, we have a lively user community doing excellent QA work, which
 exists primarily on IRC. Please make use of that resource; user feedback is
 important for any nontrivial feature, and documenting it in commit messages
 would be a good idea.
 
-[0]: git://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git
-[1]: https://evilpiepirate.org/git/ktest.git/
-[2]: https://evilpiepirate.org/~testdashboard/ci/
-[3]: linux-bcachefs@vger.kernel.org
-[4]: irc.oftc.net#bcache, #bcachefs-dev
+.. rubric:: References
+
+.. [0] git://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git
+.. [1] https://evilpiepirate.org/git/ktest.git/
+.. [2] https://evilpiepirate.org/~testdashboard/ci/
+.. [3] linux-bcachefs@vger.kernel.org
+.. [4] irc.oftc.net#bcache, #bcachefs-dev
diff --git a/Documentation/filesystems/bcachefs/casefolding.rst b/Documentation/filesystems/bcachefs/casefolding.rst
new file mode 100644
index 000000000000..ba5de97d155f
--- /dev/null
+++ b/Documentation/filesystems/bcachefs/casefolding.rst
@@ -0,0 +1,90 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Casefolding
+===========
+
+bcachefs has support for case-insensitive file and directory
+lookups using the regular `chattr +F` (`S_CASEFOLD`, `FS_CASEFOLD_FL`)
+casefolding attributes.
+
+The main usecase for casefolding is compatibility with software written
+against other filesystems that rely on casefolded lookups
+(eg. NTFS and Wine/Proton).
+Taking advantage of file-system level casefolding can lead to great
+loading time gains in many applications and games.
+
+Casefolding support requires a kernel with the `CONFIG_UNICODE` enabled.
+Once a directory has been flagged for casefolding, a feature bit
+is enabled on the superblock which marks the filesystem as using
+casefolding.
+When the feature bit for casefolding is enabled, it is no longer possible
+to mount that filesystem on kernels without `CONFIG_UNICODE` enabled.
+
+On the lookup/query side: casefolding is implemented by allocating a new
+string of `BCH_NAME_MAX` length using the `utf8_casefold` function to
+casefold the query string.
+
+On the dirent side: casefolding is implemented by ensuring the `bkey`'s
+hash is made from the casefolded string and storing the cached casefolded
+name with the regular name in the dirent.
+
+The structure looks like this:
+
+* Regular:    [dirent data][regular name][nul][nul]...
+* Casefolded: [dirent data][reg len][cf len][regular name][casefolded name][nul][nul]...
+
+(Do note, the number of NULs here is merely for illustration; their count can
+vary per-key, and they may not even be present if the key is aligned to
+`sizeof(u64)`.)
+
+This is efficient as it means that for all file lookups that require casefolding,
+it has identical performance to a regular lookup:
+a hash comparison and a `memcmp` of the name.
+
+Rationale
+---------
+
+Several designs were considered for this system:
+One was to introduce a dirent_v2, however that would be painful especially as
+the hash system only has support for a single key type. This would also need
+`BCH_NAME_MAX` to change between versions, and a new feature bit.
+
+Another option was to store without the two lengths, and just take the length of
+the regular name and casefolded name contiguously / 2 as the length. This would
+assume that the regular length == casefolded length, but that could potentially
+not be true, if the uppercase unicode glyph had a different UTF-8 encoding than
+the lowercase unicode glyph.
+It would be possible to disregard the casefold cache for those cases, but it was
+decided to simply encode the two string lengths in the key to avoid random
+performance issues if this edgecase was ever hit.
+
+The option settled on was to use a free-bit in d_type to mark a dirent as having
+a casefold cache, and then treat the first 4 bytes the name block as lengths.
+You can see this in the `d_cf_name_block` member of union in `bch_dirent`.
+
+The feature bit was used to allow casefolding support to be enabled for the majority
+of users, but some allow users who have no need for the feature to still use bcachefs as
+`CONFIG_UNICODE` can increase the kernel side a significant amount due to the tables used,
+which may be decider between using bcachefs for eg. embedded platforms.
+
+Other filesystems like ext4 and f2fs have a super-block level option for casefolding
+encoding, but bcachefs currently does not provide this. ext4 and f2fs do not expose
+any encodings than a single UTF-8 version. When future encodings are desirable,
+they will be added trivially using the opts mechanism.
+
+dentry/dcache considerations
+----------------------------
+
+Currently, in casefolded directories, bcachefs (like other filesystems) will not cache
+negative dentry's.
+
+This is because currently doing so presents a problem in the following scenario:
+
+ - Lookup file "blAH" in a casefolded directory
+ - Creation of file "BLAH" in a casefolded directory
+ - Lookup file "blAH" in a casefolded directory
+
+This would fail if negative dentry's were cached.
+
+This is slightly suboptimal, but could be fixed in future with some vfs work.
+
diff --git a/Documentation/filesystems/bcachefs/index.rst b/Documentation/filesystems/bcachefs/index.rst
index 7db4d7ceab58..3864d0ae89c1 100644
--- a/Documentation/filesystems/bcachefs/index.rst
+++ b/Documentation/filesystems/bcachefs/index.rst
@@ -4,10 +4,28 @@
 bcachefs Documentation
 ======================
 
+Subsystem-specific development process notes
+--------------------------------------------
+
+Development notes specific to bcachefs. These are intended to supplement
+:doc:`general kernel development handbook </process/index>`.
+
 .. toctree::
-   :maxdepth: 2
+   :maxdepth: 1
    :numbered:
 
    CodingStyle
    SubmittingPatches
+
+Filesystem implementation
+-------------------------
+
+Documentation for filesystem features and their implementation details.
+At this moment, only a few of these are described here.
+
+.. toctree::
+   :maxdepth: 1
+   :numbered:
+
+   casefolding
    errorcodes
diff --git a/block/blk-core.c b/block/blk-core.c
index d6c4fa3943b5..7b1103eb877d 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -793,20 +793,21 @@ void submit_bio_noacct(struct bio *bio)
 			goto end_io;
 	}
 
+	if (WARN_ON_ONCE((bio->bi_opf & REQ_PREFLUSH) &&
+			 bio_op(bio) != REQ_OP_WRITE &&
+			 bio_op(bio) != REQ_OP_ZONE_APPEND))
+		goto end_io;
+
 	/*
 	 * Filter flush bio's early so that bio based drivers without flush
 	 * support don't have to worry about them.
 	 */
-	if (op_is_flush(bio->bi_opf)) {
-		if (WARN_ON_ONCE(bio_op(bio) != REQ_OP_WRITE &&
-				 bio_op(bio) != REQ_OP_ZONE_APPEND))
+	if (op_is_flush(bio->bi_opf) &&
+	    !bdev_write_cache(bdev)) {
+		bio->bi_opf &= ~(REQ_PREFLUSH | REQ_FUA);
+		if (!bio_sectors(bio)) {
+			status = BLK_STS_OK;
 			goto end_io;
-		if (!bdev_write_cache(bdev)) {
-			bio->bi_opf &= ~(REQ_PREFLUSH | REQ_FUA);
-			if (!bio_sectors(bio)) {
-				status = BLK_STS_OK;
-				goto end_io;
-			}
 		}
 	}
 
diff --git a/fs/bcachefs/Kconfig b/fs/bcachefs/Kconfig
index fc7efd0a7525..c9798750202d 100644
--- a/fs/bcachefs/Kconfig
+++ b/fs/bcachefs/Kconfig
@@ -16,7 +16,7 @@ config BCACHEFS_FS
 	select ZSTD_COMPRESS
 	select ZSTD_DECOMPRESS
 	select CRYPTO
-	select CRYPTO_SHA256
+	select CRYPTO_LIB_SHA256
 	select CRYPTO_CHACHA20
 	select CRYPTO_POLY1305
 	select KEYS
diff --git a/fs/bcachefs/Makefile b/fs/bcachefs/Makefile
index d2689388d5e8..9af65079374f 100644
--- a/fs/bcachefs/Makefile
+++ b/fs/bcachefs/Makefile
@@ -41,7 +41,6 @@ bcachefs-y		:=	\
 	extent_update.o		\
 	eytzinger.o		\
 	fs.o			\
-	fs-common.o		\
 	fs-ioctl.o		\
 	fs-io.o			\
 	fs-io-buffered.o	\
@@ -64,9 +63,11 @@ bcachefs-y		:=	\
 	migrate.o		\
 	move.o			\
 	movinggc.o		\
+	namei.o			\
 	nocow_locking.o		\
 	opts.o			\
 	printbuf.o		\
+	progress.o		\
 	quota.o			\
 	rebalance.o		\
 	rcu_pending.o		\
diff --git a/fs/bcachefs/alloc_background.c b/fs/bcachefs/alloc_background.c
index 3ea809990ef1..5fb396be9127 100644
--- a/fs/bcachefs/alloc_background.c
+++ b/fs/bcachefs/alloc_background.c
@@ -232,7 +232,7 @@ int bch2_alloc_v3_validate(struct bch_fs *c, struct bkey_s_c k,
 	int ret = 0;
 
 	bkey_fsck_err_on(bch2_alloc_unpack_v3(&u, k),
-			 c, alloc_v2_unpack_error,
+			 c, alloc_v3_unpack_error,
 			 "unpack error");
 fsck_err:
 	return ret;
@@ -777,14 +777,12 @@ static inline int bch2_dev_data_type_accounting_mod(struct btree_trans *trans, s
 						    s64 delta_sectors,
 						    s64 delta_fragmented, unsigned flags)
 {
-	struct disk_accounting_pos acc = {
-		.type = BCH_DISK_ACCOUNTING_dev_data_type,
-		.dev_data_type.dev		= ca->dev_idx,
-		.dev_data_type.data_type	= data_type,
-	};
 	s64 d[3] = { delta_buckets, delta_sectors, delta_fragmented };
 
-	return bch2_disk_accounting_mod(trans, &acc, d, 3, flags & BTREE_TRIGGER_gc);
+	return bch2_disk_accounting_mod2(trans, flags & BTREE_TRIGGER_gc,
+					 d, dev_data_type,
+					 .dev		= ca->dev_idx,
+					 .data_type	= data_type);
 }
 
 int bch2_alloc_key_to_dev_counters(struct btree_trans *trans, struct bch_dev *ca,
@@ -837,7 +835,7 @@ int bch2_trigger_alloc(struct btree_trans *trans,
 
 	struct bch_dev *ca = bch2_dev_bucket_tryget(c, new.k->p);
 	if (!ca)
-		return -EIO;
+		return -BCH_ERR_trigger_alloc;
 
 	struct bch_alloc_v4 old_a_convert;
 	const struct bch_alloc_v4 *old_a = bch2_alloc_to_v4(old, &old_a_convert);
@@ -871,6 +869,9 @@ int bch2_trigger_alloc(struct btree_trans *trans,
 		if (data_type_is_empty(new_a->data_type) &&
 		    BCH_ALLOC_V4_NEED_INC_GEN(new_a) &&
 		    !bch2_bucket_is_open_safe(c, new.k->p.inode, new.k->p.offset)) {
+			if (new_a->oldest_gen == new_a->gen &&
+			    !bch2_bucket_sectors_total(*new_a))
+				new_a->oldest_gen++;
 			new_a->gen++;
 			SET_BCH_ALLOC_V4_NEED_INC_GEN(new_a, false);
 			alloc_data_type_set(new_a, new_a->data_type);
@@ -889,26 +890,20 @@ int bch2_trigger_alloc(struct btree_trans *trans,
 		    !new_a->io_time[READ])
 			new_a->io_time[READ] = bch2_current_io_time(c, READ);
 
-		u64 old_lru = alloc_lru_idx_read(*old_a);
-		u64 new_lru = alloc_lru_idx_read(*new_a);
-		if (old_lru != new_lru) {
-			ret = bch2_lru_change(trans, new.k->p.inode,
-					      bucket_to_u64(new.k->p),
-					      old_lru, new_lru);
-			if (ret)
-				goto err;
-		}
+		ret = bch2_lru_change(trans, new.k->p.inode,
+				      bucket_to_u64(new.k->p),
+				      alloc_lru_idx_read(*old_a),
+				      alloc_lru_idx_read(*new_a));
+		if (ret)
+			goto err;
 
-		old_lru = alloc_lru_idx_fragmentation(*old_a, ca);
-		new_lru = alloc_lru_idx_fragmentation(*new_a, ca);
-		if (old_lru != new_lru) {
-			ret = bch2_lru_change(trans,
-					BCH_LRU_FRAGMENTATION_START,
-					bucket_to_u64(new.k->p),
-					old_lru, new_lru);
-			if (ret)
-				goto err;
-		}
+		ret = bch2_lru_change(trans,
+				      BCH_LRU_BUCKET_FRAGMENTATION,
+				      bucket_to_u64(new.k->p),
+				      alloc_lru_idx_fragmentation(*old_a, ca),
+				      alloc_lru_idx_fragmentation(*new_a, ca));
+		if (ret)
+			goto err;
 
 		if (old_a->gen != new_a->gen) {
 			ret = bch2_bucket_gen_update(trans, new.k->p, new_a->gen);
@@ -1034,7 +1029,7 @@ int bch2_trigger_alloc(struct btree_trans *trans,
 invalid_bucket:
 	bch2_fs_inconsistent(c, "reference to invalid bucket\n  %s",
 			     (bch2_bkey_val_to_text(&buf, c, new.s_c), buf.buf));
-	ret = -EIO;
+	ret = -BCH_ERR_trigger_alloc;
 	goto err;
 }
 
@@ -1705,7 +1700,8 @@ static int bch2_check_alloc_to_lru_ref(struct btree_trans *trans,
 
 	u64 lru_idx = alloc_lru_idx_fragmentation(*a, ca);
 	if (lru_idx) {
-		ret = bch2_lru_check_set(trans, BCH_LRU_FRAGMENTATION_START,
+		ret = bch2_lru_check_set(trans, BCH_LRU_BUCKET_FRAGMENTATION,
+					 bucket_to_u64(alloc_k.k->p),
 					 lru_idx, alloc_k, last_flushed);
 		if (ret)
 			goto err;
@@ -1735,7 +1731,9 @@ static int bch2_check_alloc_to_lru_ref(struct btree_trans *trans,
 		a = &a_mut->v;
 	}
 
-	ret = bch2_lru_check_set(trans, alloc_k.k->p.inode, a->io_time[READ],
+	ret = bch2_lru_check_set(trans, alloc_k.k->p.inode,
+				 bucket_to_u64(alloc_k.k->p),
+				 a->io_time[READ],
 				 alloc_k, last_flushed);
 	if (ret)
 		goto err;
@@ -1757,7 +1755,8 @@ int bch2_check_alloc_to_lru_refs(struct bch_fs *c)
 		for_each_btree_key_commit(trans, iter, BTREE_ID_alloc,
 				POS_MIN, BTREE_ITER_prefetch, k,
 				NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
-			bch2_check_alloc_to_lru_ref(trans, &iter, &last_flushed)));
+			bch2_check_alloc_to_lru_ref(trans, &iter, &last_flushed))) ?:
+		bch2_check_stripe_to_lru_refs(c);
 
 	bch2_bkey_buf_exit(&last_flushed, c);
 	bch_err_fn(c, ret);
@@ -1805,6 +1804,19 @@ struct discard_buckets_state {
 	u64		discarded;
 };
 
+/*
+ * This is needed because discard is both a filesystem option and a device
+ * option, and mount options are supposed to apply to that mount and not be
+ * persisted, i.e. if it's set as a mount option we can't propagate it to the
+ * device.
+ */
+static inline bool discard_opt_enabled(struct bch_fs *c, struct bch_dev *ca)
+{
+	return test_bit(BCH_FS_discard_mount_opt_set, &c->flags)
+		? c->opts.discard
+		: ca->mi.discard;
+}
+
 static int bch2_discard_one_bucket(struct btree_trans *trans,
 				   struct bch_dev *ca,
 				   struct btree_iter *need_discard_iter,
@@ -1868,7 +1880,7 @@ static int bch2_discard_one_bucket(struct btree_trans *trans,
 		s->discarded++;
 		*discard_pos_done = iter.pos;
 
-		if (ca->mi.discard && !c->opts.nochanges) {
+		if (discard_opt_enabled(c, ca) && !c->opts.nochanges) {
 			/*
 			 * This works without any other locks because this is the only
 			 * thread that removes items from the need_discard tree
@@ -1897,7 +1909,10 @@ static int bch2_discard_one_bucket(struct btree_trans *trans,
 	if (ret)
 		goto out;
 
-	count_event(c, bucket_discard);
+	if (!fastpath)
+		count_event(c, bucket_discard);
+	else
+		count_event(c, bucket_discard_fast);
 out:
 fsck_err:
 	if (discard_locked)
@@ -2055,16 +2070,71 @@ static void bch2_discard_one_bucket_fast(struct bch_dev *ca, u64 bucket)
 	bch2_write_ref_put(c, BCH_WRITE_REF_discard_fast);
 }
 
+static int invalidate_one_bp(struct btree_trans *trans,
+			     struct bch_dev *ca,
+			     struct bkey_s_c_backpointer bp,
+			     struct bkey_buf *last_flushed)
+{
+	struct btree_iter extent_iter;
+	struct bkey_s_c extent_k =
+		bch2_backpointer_get_key(trans, bp, &extent_iter, 0, last_flushed);
+	int ret = bkey_err(extent_k);
+	if (ret)
+		return ret;
+
+	struct bkey_i *n =
+		bch2_bkey_make_mut(trans, &extent_iter, &extent_k,
+				   BTREE_UPDATE_internal_snapshot_node);
+	ret = PTR_ERR_OR_ZERO(n);
+	if (ret)
+		goto err;
+
+	bch2_bkey_drop_device(bkey_i_to_s(n), ca->dev_idx);
+err:
+	bch2_trans_iter_exit(trans, &extent_iter);
+	return ret;
+}
+
+static int invalidate_one_bucket_by_bps(struct btree_trans *trans,
+					struct bch_dev *ca,
+					struct bpos bucket,
+					u8 gen,
+					struct bkey_buf *last_flushed)
+{
+	struct bpos bp_start	= bucket_pos_to_bp_start(ca,	bucket);
+	struct bpos bp_end	= bucket_pos_to_bp_end(ca,	bucket);
+
+	return for_each_btree_key_max_commit(trans, iter, BTREE_ID_backpointers,
+				      bp_start, bp_end, 0, k,
+				      NULL, NULL,
+				      BCH_WATERMARK_btree|
+				      BCH_TRANS_COMMIT_no_enospc, ({
+		if (k.k->type != KEY_TYPE_backpointer)
+			continue;
+
+		struct bkey_s_c_backpointer bp = bkey_s_c_to_backpointer(k);
+
+		if (bp.v->bucket_gen != gen)
+			continue;
+
+		/* filter out bps with gens that don't match */
+
+		invalidate_one_bp(trans, ca, bp, last_flushed);
+	}));
+}
+
+noinline_for_stack
 static int invalidate_one_bucket(struct btree_trans *trans,
+				 struct bch_dev *ca,
 				 struct btree_iter *lru_iter,
 				 struct bkey_s_c lru_k,
+				 struct bkey_buf *last_flushed,
 				 s64 *nr_to_invalidate)
 {
 	struct bch_fs *c = trans->c;
-	struct bkey_i_alloc_v4 *a = NULL;
 	struct printbuf buf = PRINTBUF;
 	struct bpos bucket = u64_to_bucket(lru_k.k->p.offset);
-	unsigned cached_sectors;
+	struct btree_iter alloc_iter = {};
 	int ret = 0;
 
 	if (*nr_to_invalidate <= 0)
@@ -2081,35 +2151,37 @@ static int invalidate_one_bucket(struct btree_trans *trans,
 	if (bch2_bucket_is_open_safe(c, bucket.inode, bucket.offset))
 		return 0;
 
-	a = bch2_trans_start_alloc_update(trans, bucket, BTREE_TRIGGER_bucket_invalidate);
-	ret = PTR_ERR_OR_ZERO(a);
+	struct bkey_s_c alloc_k = bch2_bkey_get_iter(trans, &alloc_iter,
+						     BTREE_ID_alloc, bucket,
+						     BTREE_ITER_cached);
+	ret = bkey_err(alloc_k);
 	if (ret)
-		goto out;
+		return ret;
+
+	struct bch_alloc_v4 a_convert;
+	const struct bch_alloc_v4 *a = bch2_alloc_to_v4(alloc_k, &a_convert);
 
 	/* We expect harmless races here due to the btree write buffer: */
-	if (lru_pos_time(lru_iter->pos) != alloc_lru_idx_read(a->v))
+	if (lru_pos_time(lru_iter->pos) != alloc_lru_idx_read(*a))
 		goto out;
 
-	BUG_ON(a->v.data_type != BCH_DATA_cached);
-	BUG_ON(a->v.dirty_sectors);
+	/*
+	 * Impossible since alloc_lru_idx_read() only returns nonzero if the
+	 * bucket is supposed to be on the cached bucket LRU (i.e.
+	 * BCH_DATA_cached)
+	 *
+	 * bch2_lru_validate() also disallows lru keys with lru_pos_time() == 0
+	 */
+	BUG_ON(a->data_type != BCH_DATA_cached);
+	BUG_ON(a->dirty_sectors);
 
-	if (!a->v.cached_sectors)
+	if (!a->cached_sectors)
 		bch_err(c, "invalidating empty bucket, confused");
 
-	cached_sectors = a->v.cached_sectors;
+	unsigned cached_sectors = a->cached_sectors;
+	u8 gen = a->gen;
 
-	SET_BCH_ALLOC_V4_NEED_INC_GEN(&a->v, false);
-	a->v.gen++;
-	a->v.data_type		= 0;
-	a->v.dirty_sectors	= 0;
-	a->v.stripe_sectors	= 0;
-	a->v.cached_sectors	= 0;
-	a->v.io_time[READ]	= bch2_current_io_time(c, READ);
-	a->v.io_time[WRITE]	= bch2_current_io_time(c, WRITE);
-
-	ret = bch2_trans_commit(trans, NULL, NULL,
-				BCH_WATERMARK_btree|
-				BCH_TRANS_COMMIT_no_enospc);
+	ret = invalidate_one_bucket_by_bps(trans, ca, bucket, gen, last_flushed);
 	if (ret)
 		goto out;
 
@@ -2117,6 +2189,7 @@ static int invalidate_one_bucket(struct btree_trans *trans,
 	--*nr_to_invalidate;
 out:
 fsck_err:
+	bch2_trans_iter_exit(trans, &alloc_iter);
 	printbuf_exit(&buf);
 	return ret;
 }
@@ -2143,6 +2216,10 @@ static void bch2_do_invalidates_work(struct work_struct *work)
 	struct btree_trans *trans = bch2_trans_get(c);
 	int ret = 0;
 
+	struct bkey_buf last_flushed;
+	bch2_bkey_buf_init(&last_flushed);
+	bkey_init(&last_flushed.k->k);
+
 	ret = bch2_btree_write_buffer_tryflush(trans);
 	if (ret)
 		goto err;
@@ -2167,7 +2244,7 @@ static void bch2_do_invalidates_work(struct work_struct *work)
 		if (!k.k)
 			break;
 
-		ret = invalidate_one_bucket(trans, &iter, k, &nr_to_invalidate);
+		ret = invalidate_one_bucket(trans, ca, &iter, k, &last_flushed, &nr_to_invalidate);
 restart_err:
 		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 			continue;
@@ -2180,6 +2257,7 @@ static void bch2_do_invalidates_work(struct work_struct *work)
 err:
 	bch2_trans_put(trans);
 	percpu_ref_put(&ca->io_ref);
+	bch2_bkey_buf_exit(&last_flushed, c);
 	bch2_write_ref_put(c, BCH_WRITE_REF_invalidate);
 }
 
diff --git a/fs/bcachefs/alloc_background.h b/fs/bcachefs/alloc_background.h
index de25ba4ee94b..c556ccaffe89 100644
--- a/fs/bcachefs/alloc_background.h
+++ b/fs/bcachefs/alloc_background.h
@@ -131,7 +131,7 @@ static inline enum bch_data_type alloc_data_type(struct bch_alloc_v4 a,
 	if (a.stripe)
 		return data_type == BCH_DATA_parity ? data_type : BCH_DATA_stripe;
 	if (bch2_bucket_sectors_dirty(a))
-		return data_type;
+		return bucket_data_type(data_type);
 	if (a.cached_sectors)
 		return BCH_DATA_cached;
 	if (BCH_ALLOC_V4_NEED_DISCARD(&a))
diff --git a/fs/bcachefs/alloc_foreground.c b/fs/bcachefs/alloc_foreground.c
index 5a781fb4c794..0cac65347a5d 100644
--- a/fs/bcachefs/alloc_foreground.c
+++ b/fs/bcachefs/alloc_foreground.c
@@ -127,14 +127,14 @@ void __bch2_open_bucket_put(struct bch_fs *c, struct open_bucket *ob)
 
 void bch2_open_bucket_write_error(struct bch_fs *c,
 				  struct open_buckets *obs,
-				  unsigned dev)
+				  unsigned dev, int err)
 {
 	struct open_bucket *ob;
 	unsigned i;
 
 	open_bucket_for_each(c, obs, ob, i)
 		if (ob->dev == dev && ob->ec)
-			bch2_ec_bucket_cancel(c, ob);
+			bch2_ec_bucket_cancel(c, ob, err);
 }
 
 static struct open_bucket *bch2_open_bucket_alloc(struct bch_fs *c)
@@ -179,23 +179,6 @@ static void open_bucket_free_unused(struct bch_fs *c, struct open_bucket *ob)
 	closure_wake_up(&c->freelist_wait);
 }
 
-static inline unsigned open_buckets_reserved(enum bch_watermark watermark)
-{
-	switch (watermark) {
-	case BCH_WATERMARK_interior_updates:
-		return 0;
-	case BCH_WATERMARK_reclaim:
-		return OPEN_BUCKETS_COUNT / 6;
-	case BCH_WATERMARK_btree:
-	case BCH_WATERMARK_btree_copygc:
-		return OPEN_BUCKETS_COUNT / 4;
-	case BCH_WATERMARK_copygc:
-		return OPEN_BUCKETS_COUNT / 3;
-	default:
-		return OPEN_BUCKETS_COUNT / 2;
-	}
-}
-
 static inline bool may_alloc_bucket(struct bch_fs *c,
 				    struct bpos bucket,
 				    struct bucket_alloc_state *s)
@@ -239,7 +222,7 @@ static struct open_bucket *__try_alloc_bucket(struct bch_fs *c, struct bch_dev *
 
 	spin_lock(&c->freelist_lock);
 
-	if (unlikely(c->open_buckets_nr_free <= open_buckets_reserved(watermark))) {
+	if (unlikely(c->open_buckets_nr_free <= bch2_open_buckets_reserved(watermark))) {
 		if (cl)
 			closure_wait(&c->open_buckets_wait, cl);
 
@@ -648,7 +631,7 @@ static inline void bch2_dev_stripe_increment_inlined(struct bch_dev *ca,
 			       struct bch_dev_usage *usage)
 {
 	u64 *v = stripe->next_alloc + ca->dev_idx;
-	u64 free_space = dev_buckets_available(ca, BCH_WATERMARK_normal);
+	u64 free_space = __dev_buckets_available(ca, *usage, BCH_WATERMARK_normal);
 	u64 free_space_inv = free_space
 		? div64_u64(1ULL << 48, free_space)
 		: 1ULL << 48;
@@ -728,7 +711,7 @@ int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
 
 		struct bch_dev_usage usage;
 		struct open_bucket *ob = bch2_bucket_alloc_trans(trans, ca, watermark, data_type,
-						     cl, flags & BCH_WRITE_ALLOC_NOWAIT, &usage);
+						     cl, flags & BCH_WRITE_alloc_nowait, &usage);
 		if (!IS_ERR(ob))
 			bch2_dev_stripe_increment_inlined(ca, stripe, &usage);
 		bch2_dev_put(ca);
@@ -1336,7 +1319,7 @@ int bch2_alloc_sectors_start_trans(struct btree_trans *trans,
 	if (wp->data_type != BCH_DATA_user)
 		have_cache = true;
 
-	if (target && !(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS)) {
+	if (target && !(flags & BCH_WRITE_only_specified_devs)) {
 		ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
 					      target, erasure_code,
 					      nr_replicas, &nr_effective,
@@ -1426,7 +1409,7 @@ int bch2_alloc_sectors_start_trans(struct btree_trans *trans,
 	if (cl && bch2_err_matches(ret, BCH_ERR_open_buckets_empty))
 		ret = -BCH_ERR_bucket_alloc_blocked;
 
-	if (cl && !(flags & BCH_WRITE_ALLOC_NOWAIT) &&
+	if (cl && !(flags & BCH_WRITE_alloc_nowait) &&
 	    bch2_err_matches(ret, BCH_ERR_freelist_empty))
 		ret = -BCH_ERR_bucket_alloc_blocked;
 
diff --git a/fs/bcachefs/alloc_foreground.h b/fs/bcachefs/alloc_foreground.h
index f25481a0d1a0..69ec6a012898 100644
--- a/fs/bcachefs/alloc_foreground.h
+++ b/fs/bcachefs/alloc_foreground.h
@@ -33,6 +33,23 @@ static inline struct bch_dev *ob_dev(struct bch_fs *c, struct open_bucket *ob)
 	return bch2_dev_have_ref(c, ob->dev);
 }
 
+static inline unsigned bch2_open_buckets_reserved(enum bch_watermark watermark)
+{
+	switch (watermark) {
+	case BCH_WATERMARK_interior_updates:
+		return 0;
+	case BCH_WATERMARK_reclaim:
+		return OPEN_BUCKETS_COUNT / 6;
+	case BCH_WATERMARK_btree:
+	case BCH_WATERMARK_btree_copygc:
+		return OPEN_BUCKETS_COUNT / 4;
+	case BCH_WATERMARK_copygc:
+		return OPEN_BUCKETS_COUNT / 3;
+	default:
+		return OPEN_BUCKETS_COUNT / 2;
+	}
+}
+
 struct open_bucket *bch2_bucket_alloc(struct bch_fs *, struct bch_dev *,
 				      enum bch_watermark, enum bch_data_type,
 				      struct closure *);
@@ -65,7 +82,7 @@ static inline struct open_bucket *ec_open_bucket(struct bch_fs *c,
 }
 
 void bch2_open_bucket_write_error(struct bch_fs *,
-			struct open_buckets *, unsigned);
+			struct open_buckets *, unsigned, int);
 
 void __bch2_open_bucket_put(struct bch_fs *, struct open_bucket *);
 
diff --git a/fs/bcachefs/alloc_types.h b/fs/bcachefs/alloc_types.h
index 4aa8ee026cb8..8f79f46c2a78 100644
--- a/fs/bcachefs/alloc_types.h
+++ b/fs/bcachefs/alloc_types.h
@@ -90,6 +90,7 @@ struct dev_stripe_state {
 	x(stopped)			\
 	x(waiting_io)			\
 	x(waiting_work)			\
+	x(runnable)			\
 	x(running)
 
 enum write_point_state {
@@ -125,6 +126,7 @@ struct write_point {
 		enum write_point_state	state;
 		u64			last_state_change;
 		u64			time[WRITE_POINT_STATE_NR];
+		u64			last_runtime;
 	} __aligned(SMP_CACHE_BYTES);
 };
 
diff --git a/fs/bcachefs/backpointers.c b/fs/bcachefs/backpointers.c
index ebeb6a5ff9d2..20c497f0c2cb 100644
--- a/fs/bcachefs/backpointers.c
+++ b/fs/bcachefs/backpointers.c
@@ -11,6 +11,7 @@
 #include "checksum.h"
 #include "disk_accounting.h"
 #include "error.h"
+#include "progress.h"
 
 #include <linux/mm.h>
 
@@ -49,6 +50,8 @@ void bch2_backpointer_to_text(struct printbuf *out, struct bch_fs *c, struct bke
 	}
 
 	bch2_btree_id_level_to_text(out, bp.v->btree_id, bp.v->level);
+	prt_str(out, " data_type=");
+	bch2_prt_data_type(out, bp.v->data_type);
 	prt_printf(out, " suboffset=%u len=%u gen=%u pos=",
 		   (u32) bp.k->p.offset & ~(~0U << MAX_EXTENT_COMPRESS_RATIO_SHIFT),
 		   bp.v->bucket_len,
@@ -244,27 +247,31 @@ struct bkey_s_c bch2_backpointer_get_key(struct btree_trans *trans,
 	if (unlikely(bp.v->btree_id >= btree_id_nr_alive(c)))
 		return bkey_s_c_null;
 
-	if (likely(!bp.v->level)) {
-		bch2_trans_node_iter_init(trans, iter,
-					  bp.v->btree_id,
-					  bp.v->pos,
-					  0, 0,
-					  iter_flags);
-		struct bkey_s_c k = bch2_btree_iter_peek_slot(iter);
-		if (bkey_err(k)) {
-			bch2_trans_iter_exit(trans, iter);
-			return k;
-		}
+	bch2_trans_node_iter_init(trans, iter,
+				  bp.v->btree_id,
+				  bp.v->pos,
+				  0,
+				  bp.v->level,
+				  iter_flags);
+	struct bkey_s_c k = bch2_btree_iter_peek_slot(iter);
+	if (bkey_err(k)) {
+		bch2_trans_iter_exit(trans, iter);
+		return k;
+	}
 
-		if (k.k &&
-		    extent_matches_bp(c, bp.v->btree_id, bp.v->level, k, bp))
-			return k;
+	if (k.k &&
+	    extent_matches_bp(c, bp.v->btree_id, bp.v->level, k, bp))
+		return k;
 
-		bch2_trans_iter_exit(trans, iter);
+	bch2_trans_iter_exit(trans, iter);
+
+	if (!bp.v->level) {
 		int ret = backpointer_target_not_found(trans, bp, k, last_flushed);
 		return ret ? bkey_s_c_err(ret) : bkey_s_c_null;
 	} else {
 		struct btree *b = bch2_backpointer_get_node(trans, bp, iter, last_flushed);
+		if (b == ERR_PTR(-BCH_ERR_backpointer_to_overwritten_btree_node))
+			return bkey_s_c_null;
 		if (IS_ERR_OR_NULL(b))
 			return ((struct bkey_s_c) { .k = ERR_CAST(b) });
 
@@ -514,6 +521,22 @@ static int check_bp_exists(struct btree_trans *trans,
 	if (!other_extent.k)
 		goto missing;
 
+	rcu_read_lock();
+	struct bch_dev *ca = bch2_dev_rcu_noerror(c, bp->k.p.inode);
+	if (ca) {
+		struct bkey_ptrs_c other_extent_ptrs = bch2_bkey_ptrs_c(other_extent);
+		bkey_for_each_ptr(other_extent_ptrs, ptr)
+			if (ptr->dev == bp->k.p.inode &&
+			    dev_ptr_stale_rcu(ca, ptr)) {
+				ret = drop_dev_and_update(trans, other_bp.v->btree_id,
+							  other_extent, bp->k.p.inode);
+				if (ret)
+					goto err;
+				goto out;
+			}
+	}
+	rcu_read_unlock();
+
 	if (bch2_extents_match(orig_k, other_extent)) {
 		printbuf_reset(&buf);
 		prt_printf(&buf, "duplicate versions of same extent, deleting smaller\n  ");
@@ -590,9 +613,6 @@ static int check_extent_to_backpointers(struct btree_trans *trans,
 	struct extent_ptr_decoded p;
 
 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
-		if (p.ptr.cached)
-			continue;
-
 		if (p.ptr.dev == BCH_SB_MEMBER_INVALID)
 			continue;
 
@@ -600,9 +620,11 @@ static int check_extent_to_backpointers(struct btree_trans *trans,
 		struct bch_dev *ca = bch2_dev_rcu_noerror(c, p.ptr.dev);
 		bool check = ca && test_bit(PTR_BUCKET_NR(ca, &p.ptr), ca->bucket_backpointer_mismatches);
 		bool empty = ca && test_bit(PTR_BUCKET_NR(ca, &p.ptr), ca->bucket_backpointer_empty);
+
+		bool stale = p.ptr.cached && (!ca || dev_ptr_stale_rcu(ca, &p.ptr));
 		rcu_read_unlock();
 
-		if (check || empty) {
+		if ((check || empty) && !stale) {
 			struct bkey_i_backpointer bp;
 			bch2_extent_ptr_to_bp(c, btree, level, k, p, entry, &bp);
 
@@ -715,71 +737,6 @@ static int bch2_get_btree_in_memory_pos(struct btree_trans *trans,
 	return ret;
 }
 
-struct progress_indicator_state {
-	unsigned long		next_print;
-	u64			nodes_seen;
-	u64			nodes_total;
-	struct btree		*last_node;
-};
-
-static inline void progress_init(struct progress_indicator_state *s,
-				 struct bch_fs *c,
-				 u64 btree_id_mask)
-{
-	memset(s, 0, sizeof(*s));
-
-	s->next_print = jiffies + HZ * 10;
-
-	for (unsigned i = 0; i < BTREE_ID_NR; i++) {
-		if (!(btree_id_mask & BIT_ULL(i)))
-			continue;
-
-		struct disk_accounting_pos acc = {
-			.type		= BCH_DISK_ACCOUNTING_btree,
-			.btree.id	= i,
-		};
-
-		u64 v;
-		bch2_accounting_mem_read(c, disk_accounting_pos_to_bpos(&acc), &v, 1);
-		s->nodes_total += div64_ul(v, btree_sectors(c));
-	}
-}
-
-static inline bool progress_update_p(struct progress_indicator_state *s)
-{
-	bool ret = time_after_eq(jiffies, s->next_print);
-
-	if (ret)
-		s->next_print = jiffies + HZ * 10;
-	return ret;
-}
-
-static void progress_update_iter(struct btree_trans *trans,
-				 struct progress_indicator_state *s,
-				 struct btree_iter *iter,
-				 const char *msg)
-{
-	struct bch_fs *c = trans->c;
-	struct btree *b = path_l(btree_iter_path(trans, iter))->b;
-
-	s->nodes_seen += b != s->last_node;
-	s->last_node = b;
-
-	if (progress_update_p(s)) {
-		struct printbuf buf = PRINTBUF;
-		unsigned percent = s->nodes_total
-			? div64_u64(s->nodes_seen * 100, s->nodes_total)
-			: 0;
-
-		prt_printf(&buf, "%s: %d%%, done %llu/%llu nodes, at ",
-			   msg, percent, s->nodes_seen, s->nodes_total);
-		bch2_bbpos_to_text(&buf, BBPOS(iter->btree_id, iter->pos));
-
-		bch_info(c, "%s", buf.buf);
-		printbuf_exit(&buf);
-	}
-}
-
 static int bch2_check_extents_to_backpointers_pass(struct btree_trans *trans,
 						   struct extents_to_bp_state *s)
 {
@@ -787,7 +744,7 @@ static int bch2_check_extents_to_backpointers_pass(struct btree_trans *trans,
 	struct progress_indicator_state progress;
 	int ret = 0;
 
-	progress_init(&progress, trans->c, BIT_ULL(BTREE_ID_extents)|BIT_ULL(BTREE_ID_reflink));
+	bch2_progress_init(&progress, trans->c, BIT_ULL(BTREE_ID_extents)|BIT_ULL(BTREE_ID_reflink));
 
 	for (enum btree_id btree_id = 0;
 	     btree_id < btree_id_nr_alive(c);
@@ -806,7 +763,7 @@ static int bch2_check_extents_to_backpointers_pass(struct btree_trans *trans,
 						  BTREE_ITER_prefetch);
 
 			ret = for_each_btree_key_continue(trans, iter, 0, k, ({
-				progress_update_iter(trans, &progress, &iter, "extents_to_backpointers");
+				bch2_progress_update_iter(trans, &progress, &iter, "extents_to_backpointers");
 				check_extent_to_backpointers(trans, s, btree_id, level, k) ?:
 				bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
 			}));
@@ -827,7 +784,7 @@ enum alloc_sector_counter {
 	ALLOC_SECTORS_NR
 };
 
-static enum alloc_sector_counter data_type_to_alloc_counter(enum bch_data_type t)
+static int data_type_to_alloc_counter(enum bch_data_type t)
 {
 	switch (t) {
 	case BCH_DATA_btree:
@@ -836,9 +793,10 @@ static enum alloc_sector_counter data_type_to_alloc_counter(enum bch_data_type t
 	case BCH_DATA_cached:
 		return ALLOC_cached;
 	case BCH_DATA_stripe:
+	case BCH_DATA_parity:
 		return ALLOC_stripe;
 	default:
-		BUG();
+		return -1;
 	}
 }
 
@@ -889,7 +847,11 @@ static int check_bucket_backpointer_mismatch(struct btree_trans *trans, struct b
 		if (bp.v->bucket_gen != a->gen)
 			continue;
 
-		sectors[data_type_to_alloc_counter(bp.v->data_type)] += bp.v->bucket_len;
+		int alloc_counter = data_type_to_alloc_counter(bp.v->data_type);
+		if (alloc_counter < 0)
+			continue;
+
+		sectors[alloc_counter] += bp.v->bucket_len;
 	};
 	bch2_trans_iter_exit(trans, &iter);
 	if (ret)
@@ -901,9 +863,8 @@ static int check_bucket_backpointer_mismatch(struct btree_trans *trans, struct b
 			goto err;
 	}
 
-	/* Cached pointers don't have backpointers: */
-
 	if (sectors[ALLOC_dirty]  != a->dirty_sectors ||
+	    sectors[ALLOC_cached] != a->cached_sectors ||
 	    sectors[ALLOC_stripe] != a->stripe_sectors) {
 		if (c->sb.version_upgrade_complete >= bcachefs_metadata_version_backpointer_bucket_gen) {
 			ret = bch2_backpointers_maybe_flush(trans, alloc_k, last_flushed);
@@ -912,6 +873,7 @@ static int check_bucket_backpointer_mismatch(struct btree_trans *trans, struct b
 		}
 
 		if (sectors[ALLOC_dirty]  > a->dirty_sectors ||
+		    sectors[ALLOC_cached] > a->cached_sectors ||
 		    sectors[ALLOC_stripe] > a->stripe_sectors) {
 			ret = check_bucket_backpointers_to_extents(trans, ca, alloc_k.k->p) ?:
 				-BCH_ERR_transaction_restart_nested;
@@ -919,7 +881,8 @@ static int check_bucket_backpointer_mismatch(struct btree_trans *trans, struct b
 		}
 
 		if (!sectors[ALLOC_dirty] &&
-		    !sectors[ALLOC_stripe])
+		    !sectors[ALLOC_stripe] &&
+		    !sectors[ALLOC_cached])
 			__set_bit(alloc_k.k->p.offset, ca->bucket_backpointer_empty);
 		else
 			__set_bit(alloc_k.k->p.offset, ca->bucket_backpointer_mismatches);
@@ -1206,11 +1169,11 @@ static int bch2_check_backpointers_to_extents_pass(struct btree_trans *trans,
 
 	bch2_bkey_buf_init(&last_flushed);
 	bkey_init(&last_flushed.k->k);
-	progress_init(&progress, trans->c, BIT_ULL(BTREE_ID_backpointers));
+	bch2_progress_init(&progress, trans->c, BIT_ULL(BTREE_ID_backpointers));
 
 	int ret = for_each_btree_key(trans, iter, BTREE_ID_backpointers,
 				     POS_MIN, BTREE_ITER_prefetch, k, ({
-			progress_update_iter(trans, &progress, &iter, "backpointers_to_extents");
+			bch2_progress_update_iter(trans, &progress, &iter, "backpointers_to_extents");
 			check_one_backpointer(trans, start, end, k, &last_flushed);
 	}));
 
diff --git a/fs/bcachefs/backpointers.h b/fs/bcachefs/backpointers.h
index 060dad1521ee..16575dbc5736 100644
--- a/fs/bcachefs/backpointers.h
+++ b/fs/bcachefs/backpointers.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _BCACHEFS_BACKPOINTERS_BACKGROUND_H
-#define _BCACHEFS_BACKPOINTERS_BACKGROUND_H
+#ifndef _BCACHEFS_BACKPOINTERS_H
+#define _BCACHEFS_BACKPOINTERS_H
 
 #include "btree_cache.h"
 #include "btree_iter.h"
@@ -123,7 +123,12 @@ static inline enum bch_data_type bch2_bkey_ptr_data_type(struct bkey_s_c k,
 		return BCH_DATA_btree;
 	case KEY_TYPE_extent:
 	case KEY_TYPE_reflink_v:
-		return p.has_ec ? BCH_DATA_stripe : BCH_DATA_user;
+		if (p.has_ec)
+			return BCH_DATA_stripe;
+		if (p.ptr.cached)
+			return BCH_DATA_cached;
+		else
+			return BCH_DATA_user;
 	case KEY_TYPE_stripe: {
 		const struct bch_extent_ptr *ptr = &entry->ptr;
 		struct bkey_s_c_stripe s = bkey_s_c_to_stripe(k);
@@ -147,7 +152,20 @@ static inline void bch2_extent_ptr_to_bp(struct bch_fs *c,
 			   struct bkey_i_backpointer *bp)
 {
 	bkey_backpointer_init(&bp->k_i);
-	bp->k.p = POS(p.ptr.dev, ((u64) p.ptr.offset << MAX_EXTENT_COMPRESS_RATIO_SHIFT) + p.crc.offset);
+	bp->k.p.inode = p.ptr.dev;
+
+	if (k.k->type != KEY_TYPE_stripe)
+		bp->k.p.offset = ((u64) p.ptr.offset << MAX_EXTENT_COMPRESS_RATIO_SHIFT) + p.crc.offset;
+	else {
+		/*
+		 * Put stripe backpointers where they won't collide with the
+		 * extent backpointers within the stripe:
+		 */
+		struct bkey_s_c_stripe s = bkey_s_c_to_stripe(k);
+		bp->k.p.offset = ((u64) (p.ptr.offset + le16_to_cpu(s.v->sectors)) <<
+				  MAX_EXTENT_COMPRESS_RATIO_SHIFT) - 1;
+	}
+
 	bp->v	= (struct bch_backpointer) {
 		.btree_id	= btree_id,
 		.level		= level,
diff --git a/fs/bcachefs/bcachefs.h b/fs/bcachefs/bcachefs.h
index 161cf2f05d2a..f52311017aee 100644
--- a/fs/bcachefs/bcachefs.h
+++ b/fs/bcachefs/bcachefs.h
@@ -203,6 +203,7 @@
 #include <linux/types.h>
 #include <linux/workqueue.h>
 #include <linux/zstd.h>
+#include <linux/unicode.h>
 
 #include "bcachefs_format.h"
 #include "btree_journal_iter_types.h"
@@ -444,6 +445,7 @@ BCH_DEBUG_PARAMS_DEBUG()
 	x(btree_node_sort)			\
 	x(btree_node_read)			\
 	x(btree_node_read_done)			\
+	x(btree_node_write)			\
 	x(btree_interior_update_foreground)	\
 	x(btree_interior_update_total)		\
 	x(btree_gc)				\
@@ -456,6 +458,7 @@ BCH_DEBUG_PARAMS_DEBUG()
 	x(blocked_journal_low_on_space)		\
 	x(blocked_journal_low_on_pin)		\
 	x(blocked_journal_max_in_flight)	\
+	x(blocked_journal_max_open)		\
 	x(blocked_key_cache_flush)		\
 	x(blocked_allocate)			\
 	x(blocked_allocate_open_bucket)		\
@@ -533,6 +536,7 @@ struct bch_dev {
 	 */
 	struct bch_member_cpu	mi;
 	atomic64_t		errors[BCH_MEMBER_ERROR_NR];
+	unsigned long		write_errors_start;
 
 	__uuid_t		uuid;
 	char			name[BDEVNAME_SIZE];
@@ -623,7 +627,8 @@ struct bch_dev {
 	x(topology_error)		\
 	x(errors_fixed)			\
 	x(errors_not_fixed)		\
-	x(no_invalid_checks)
+	x(no_invalid_checks)		\
+	x(discard_mount_opt_set)	\
 
 enum bch_fs_flags {
 #define x(n)		BCH_FS_##n,
@@ -687,7 +692,8 @@ struct btree_trans_buf {
 	x(gc_gens)							\
 	x(snapshot_delete_pagecache)					\
 	x(sysfs)							\
-	x(btree_write_buffer)
+	x(btree_write_buffer)						\
+	x(btree_node_scrub)
 
 enum bch_write_ref {
 #define x(n) BCH_WRITE_REF_##n,
@@ -696,6 +702,8 @@ enum bch_write_ref {
 	BCH_WRITE_REF_NR,
 };
 
+#define BCH_FS_DEFAULT_UTF8_ENCODING UNICODE_AGE(12, 1, 0)
+
 struct bch_fs {
 	struct closure		cl;
 
@@ -780,6 +788,9 @@ struct bch_fs {
 		u64		btrees_lost_data;
 	}			sb;
 
+#ifdef CONFIG_UNICODE
+	struct unicode_map	*cf_encoding;
+#endif
 
 	struct bch_sb_handle	disk_sb;
 
@@ -969,7 +980,6 @@ struct bch_fs {
 	mempool_t		compress_workspace[BCH_COMPRESSION_OPT_NR];
 	size_t			zstd_workspace_size;
 
-	struct crypto_shash	*sha256;
 	struct crypto_sync_skcipher *chacha20;
 	struct crypto_shash	*poly1305;
 
@@ -993,15 +1003,11 @@ struct bch_fs {
 	wait_queue_head_t	copygc_running_wq;
 
 	/* STRIPES: */
-	GENRADIX(struct stripe) stripes;
 	GENRADIX(struct gc_stripe) gc_stripes;
 
 	struct hlist_head	ec_stripes_new[32];
 	spinlock_t		ec_stripes_new_lock;
 
-	ec_stripes_heap		ec_stripes_heap;
-	struct mutex		ec_stripes_heap_lock;
-
 	/* ERASURE CODING */
 	struct list_head	ec_stripe_head_list;
 	struct mutex		ec_stripe_head_lock;
diff --git a/fs/bcachefs/bcachefs_format.h b/fs/bcachefs/bcachefs_format.h
index f70f0108401f..e96d87767020 100644
--- a/fs/bcachefs/bcachefs_format.h
+++ b/fs/bcachefs/bcachefs_format.h
@@ -686,7 +686,12 @@ struct bch_sb_field_ext {
 	x(inode_depth,			BCH_VERSION(1, 17))		\
 	x(persistent_inode_cursors,	BCH_VERSION(1, 18))		\
 	x(autofix_errors,		BCH_VERSION(1, 19))		\
-	x(directory_size,		BCH_VERSION(1, 20))
+	x(directory_size,		BCH_VERSION(1, 20))		\
+	x(cached_backpointers,		BCH_VERSION(1, 21))		\
+	x(stripe_backpointers,		BCH_VERSION(1, 22))		\
+	x(stripe_lru,			BCH_VERSION(1, 23))		\
+	x(casefolding,			BCH_VERSION(1, 24))		\
+	x(extent_flags,			BCH_VERSION(1, 25))
 
 enum bcachefs_metadata_version {
 	bcachefs_metadata_version_min = 9,
@@ -837,6 +842,7 @@ LE64_BITMASK(BCH_SB_SHARD_INUMS,	struct bch_sb, flags[3], 28, 29);
 LE64_BITMASK(BCH_SB_INODES_USE_KEY_CACHE,struct bch_sb, flags[3], 29, 30);
 LE64_BITMASK(BCH_SB_JOURNAL_FLUSH_DELAY,struct bch_sb, flags[3], 30, 62);
 LE64_BITMASK(BCH_SB_JOURNAL_FLUSH_DISABLED,struct bch_sb, flags[3], 62, 63);
+/* one free bit */
 LE64_BITMASK(BCH_SB_JOURNAL_RECLAIM_DELAY,struct bch_sb, flags[4], 0, 32);
 LE64_BITMASK(BCH_SB_JOURNAL_TRANSACTION_NAMES,struct bch_sb, flags[4], 32, 33);
 LE64_BITMASK(BCH_SB_NOCOW,		struct bch_sb, flags[4], 33, 34);
@@ -855,6 +861,8 @@ LE64_BITMASK(BCH_SB_VERSION_INCOMPAT,	struct bch_sb, flags[5], 32, 48);
 LE64_BITMASK(BCH_SB_VERSION_INCOMPAT_ALLOWED,
 					struct bch_sb, flags[5], 48, 64);
 LE64_BITMASK(BCH_SB_SHARD_INUMS_NBITS,	struct bch_sb, flags[6],  0,  4);
+LE64_BITMASK(BCH_SB_WRITE_ERROR_TIMEOUT,struct bch_sb, flags[6],  4, 14);
+LE64_BITMASK(BCH_SB_CSUM_ERR_RETRY_NR,	struct bch_sb, flags[6], 14, 20);
 
 static inline __u64 BCH_SB_COMPRESSION_TYPE(const struct bch_sb *sb)
 {
@@ -908,7 +916,8 @@ static inline void SET_BCH_SB_BACKGROUND_COMPRESSION_TYPE(struct bch_sb *sb, __u
 	x(journal_no_flush,		16)	\
 	x(alloc_v2,			17)	\
 	x(extents_across_btree_nodes,	18)	\
-	x(incompat_version_field,	19)
+	x(incompat_version_field,	19)	\
+	x(casefolding,			20)
 
 #define BCH_SB_FEATURES_ALWAYS				\
 	(BIT_ULL(BCH_FEATURE_new_extent_overwrite)|	\
@@ -922,7 +931,8 @@ static inline void SET_BCH_SB_BACKGROUND_COMPRESSION_TYPE(struct bch_sb *sb, __u
 	 BIT_ULL(BCH_FEATURE_new_siphash)|		\
 	 BIT_ULL(BCH_FEATURE_btree_ptr_v2)|		\
 	 BIT_ULL(BCH_FEATURE_new_varint)|		\
-	 BIT_ULL(BCH_FEATURE_journal_no_flush))
+	 BIT_ULL(BCH_FEATURE_journal_no_flush)|		\
+	 BIT_ULL(BCH_FEATURE_incompat_version_field))
 
 enum bch_sb_feature {
 #define x(f, n) BCH_FEATURE_##f,
diff --git a/fs/bcachefs/bcachefs_ioctl.h b/fs/bcachefs/bcachefs_ioctl.h
index 3c23bdf788ce..52594e925eb7 100644
--- a/fs/bcachefs/bcachefs_ioctl.h
+++ b/fs/bcachefs/bcachefs_ioctl.h
@@ -87,6 +87,7 @@ struct bch_ioctl_incremental {
 #define BCH_IOCTL_FSCK_OFFLINE	_IOW(0xbc,	19,  struct bch_ioctl_fsck_offline)
 #define BCH_IOCTL_FSCK_ONLINE	_IOW(0xbc,	20,  struct bch_ioctl_fsck_online)
 #define BCH_IOCTL_QUERY_ACCOUNTING _IOW(0xbc,	21,  struct bch_ioctl_query_accounting)
+#define BCH_IOCTL_QUERY_COUNTERS _IOW(0xbc,	21,  struct bch_ioctl_query_counters)
 
 /* ioctl below act on a particular file, not the filesystem as a whole: */
 
@@ -213,6 +214,10 @@ struct bch_ioctl_data {
 	struct bpos		end_pos;
 
 	union {
+	struct {
+		__u32		dev;
+		__u32		data_types;
+	}			scrub;
 	struct {
 		__u32		dev;
 		__u32		pad;
@@ -229,6 +234,11 @@ enum bch_data_event {
 	BCH_DATA_EVENT_NR	= 1,
 };
 
+enum data_progress_data_type_special {
+	DATA_PROGRESS_DATA_TYPE_phys	= 254,
+	DATA_PROGRESS_DATA_TYPE_done	= 255,
+};
+
 struct bch_ioctl_data_progress {
 	__u8			data_type;
 	__u8			btree_id;
@@ -237,11 +247,19 @@ struct bch_ioctl_data_progress {
 
 	__u64			sectors_done;
 	__u64			sectors_total;
+	__u64			sectors_error_corrected;
+	__u64			sectors_error_uncorrected;
 } __packed __aligned(8);
 
+enum bch_ioctl_data_event_ret {
+	BCH_IOCTL_DATA_EVENT_RET_done		= 1,
+	BCH_IOCTL_DATA_EVENT_RET_device_offline	= 2,
+};
+
 struct bch_ioctl_data_event {
 	__u8			type;
-	__u8			pad[7];
+	__u8			ret;
+	__u8			pad[6];
 	union {
 	struct bch_ioctl_data_progress p;
 	__u64			pad2[15];
@@ -443,4 +461,13 @@ struct bch_ioctl_query_accounting {
 	struct bkey_i_accounting accounting[];
 };
 
+#define BCH_IOCTL_QUERY_COUNTERS_MOUNT	(1 << 0)
+
+struct bch_ioctl_query_counters {
+	__u16			nr;
+	__u16			flags;
+	__u32			pad;
+	__u64			d[];
+};
+
 #endif /* _BCACHEFS_IOCTL_H */
diff --git a/fs/bcachefs/bkey.h b/fs/bcachefs/bkey.h
index 054e2d5e8448..082632905649 100644
--- a/fs/bcachefs/bkey.h
+++ b/fs/bcachefs/bkey.h
@@ -191,6 +191,7 @@ static inline struct bpos bkey_max(struct bpos l, struct bpos r)
 static inline bool bkey_and_val_eq(struct bkey_s_c l, struct bkey_s_c r)
 {
 	return bpos_eq(l.k->p, r.k->p) &&
+		l.k->size == r.k->size &&
 		bkey_bytes(l.k) == bkey_bytes(r.k) &&
 		!memcmp(l.v, r.v, bkey_val_bytes(l.k));
 }
diff --git a/fs/bcachefs/btree_cache.c b/fs/bcachefs/btree_cache.c
index 1ec1f90e0eb3..54666027aa85 100644
--- a/fs/bcachefs/btree_cache.c
+++ b/fs/bcachefs/btree_cache.c
@@ -610,6 +610,7 @@ void bch2_fs_btree_cache_exit(struct bch_fs *c)
 		       btree_node_write_in_flight(b));
 
 		btree_node_data_free(bc, b);
+		cond_resched();
 	}
 
 	BUG_ON(!bch2_journal_error(&c->journal) &&
diff --git a/fs/bcachefs/btree_gc.c b/fs/bcachefs/btree_gc.c
index dd1d9b74076e..ff681e733598 100644
--- a/fs/bcachefs/btree_gc.c
+++ b/fs/bcachefs/btree_gc.c
@@ -27,6 +27,7 @@
 #include "journal.h"
 #include "keylist.h"
 #include "move.h"
+#include "progress.h"
 #include "recovery_passes.h"
 #include "reflink.h"
 #include "recovery.h"
@@ -656,7 +657,9 @@ static int bch2_gc_mark_key(struct btree_trans *trans, enum btree_id btree_id,
 	return ret;
 }
 
-static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree, bool initial)
+static int bch2_gc_btree(struct btree_trans *trans,
+			 struct progress_indicator_state *progress,
+			 enum btree_id btree, bool initial)
 {
 	struct bch_fs *c = trans->c;
 	unsigned target_depth = btree_node_type_has_triggers(__btree_node_type(0, btree)) ? 0 : 1;
@@ -673,6 +676,7 @@ static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree, bool in
 					  BTREE_ITER_prefetch);
 
 		ret = for_each_btree_key_continue(trans, iter, 0, k, ({
+			bch2_progress_update_iter(trans, progress, &iter, "check_allocations");
 			gc_pos_set(c, gc_pos_btree(btree, level, k.k->p));
 			bch2_gc_mark_key(trans, btree, level, &prev, &iter, k, initial);
 		}));
@@ -717,22 +721,24 @@ static inline int btree_id_gc_phase_cmp(enum btree_id l, enum btree_id r)
 static int bch2_gc_btrees(struct bch_fs *c)
 {
 	struct btree_trans *trans = bch2_trans_get(c);
-	enum btree_id ids[BTREE_ID_NR];
 	struct printbuf buf = PRINTBUF;
-	unsigned i;
 	int ret = 0;
 
-	for (i = 0; i < BTREE_ID_NR; i++)
+	struct progress_indicator_state progress;
+	bch2_progress_init(&progress, c, ~0ULL);
+
+	enum btree_id ids[BTREE_ID_NR];
+	for (unsigned i = 0; i < BTREE_ID_NR; i++)
 		ids[i] = i;
 	bubble_sort(ids, BTREE_ID_NR, btree_id_gc_phase_cmp);
 
-	for (i = 0; i < btree_id_nr_alive(c) && !ret; i++) {
+	for (unsigned i = 0; i < btree_id_nr_alive(c) && !ret; i++) {
 		unsigned btree = i < BTREE_ID_NR ? ids[i] : i;
 
 		if (IS_ERR_OR_NULL(bch2_btree_id_root(c, btree)->b))
 			continue;
 
-		ret = bch2_gc_btree(trans, btree, true);
+		ret = bch2_gc_btree(trans, &progress, btree, true);
 	}
 
 	printbuf_exit(&buf);
diff --git a/fs/bcachefs/btree_io.c b/fs/bcachefs/btree_io.c
index 756736f9243d..2ba33ffc9795 100644
--- a/fs/bcachefs/btree_io.c
+++ b/fs/bcachefs/btree_io.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 
 #include "bcachefs.h"
+#include "bkey_buf.h"
 #include "bkey_methods.h"
 #include "bkey_sort.h"
 #include "btree_cache.h"
@@ -1328,6 +1329,7 @@ static void btree_node_read_work(struct work_struct *work)
 		bch_info(c, "retrying read");
 		ca = bch2_dev_get_ioref(c, rb->pick.ptr.dev, READ);
 		rb->have_ioref		= ca != NULL;
+		rb->start_time		= local_clock();
 		bio_reset(bio, NULL, REQ_OP_READ|REQ_SYNC|REQ_META);
 		bio->bi_iter.bi_sector	= rb->pick.ptr.offset;
 		bio->bi_iter.bi_size	= btree_buf_bytes(b);
@@ -1338,21 +1340,26 @@ static void btree_node_read_work(struct work_struct *work)
 		} else {
 			bio->bi_status = BLK_STS_REMOVED;
 		}
+
+		bch2_account_io_completion(ca, BCH_MEMBER_ERROR_read,
+					   rb->start_time, !bio->bi_status);
 start:
 		printbuf_reset(&buf);
 		bch2_btree_pos_to_text(&buf, c, b);
-		bch2_dev_io_err_on(ca && bio->bi_status, ca, BCH_MEMBER_ERROR_read,
-				   "btree read error %s for %s",
-				   bch2_blk_status_to_str(bio->bi_status), buf.buf);
+
+		if (ca && bio->bi_status)
+			bch_err_dev_ratelimited(ca,
+					"btree read error %s for %s",
+					bch2_blk_status_to_str(bio->bi_status), buf.buf);
 		if (rb->have_ioref)
 			percpu_ref_put(&ca->io_ref);
 		rb->have_ioref = false;
 
-		bch2_mark_io_failure(&failed, &rb->pick);
+		bch2_mark_io_failure(&failed, &rb->pick, false);
 
 		can_retry = bch2_bkey_pick_read_device(c,
 				bkey_i_to_s_c(&b->key),
-				&failed, &rb->pick) > 0;
+				&failed, &rb->pick, -1) > 0;
 
 		if (!bio->bi_status &&
 		    !bch2_btree_node_read_done(c, ca, b, can_retry, &saw_error)) {
@@ -1400,12 +1407,11 @@ static void btree_node_read_endio(struct bio *bio)
 	struct btree_read_bio *rb =
 		container_of(bio, struct btree_read_bio, bio);
 	struct bch_fs *c	= rb->c;
+	struct bch_dev *ca	= rb->have_ioref
+		? bch2_dev_have_ref(c, rb->pick.ptr.dev) : NULL;
 
-	if (rb->have_ioref) {
-		struct bch_dev *ca = bch2_dev_have_ref(c, rb->pick.ptr.dev);
-
-		bch2_latency_acct(ca, rb->start_time, READ);
-	}
+	bch2_account_io_completion(ca, BCH_MEMBER_ERROR_read,
+				   rb->start_time, !bio->bi_status);
 
 	queue_work(c->btree_read_complete_wq, &rb->work);
 }
@@ -1697,7 +1703,7 @@ void bch2_btree_node_read(struct btree_trans *trans, struct btree *b,
 		return;
 
 	ret = bch2_bkey_pick_read_device(c, bkey_i_to_s_c(&b->key),
-					 NULL, &pick);
+					 NULL, &pick, -1);
 
 	if (ret <= 0) {
 		struct printbuf buf = PRINTBUF;
@@ -1811,6 +1817,190 @@ int bch2_btree_root_read(struct bch_fs *c, enum btree_id id,
 	return bch2_trans_run(c, __bch2_btree_root_read(trans, id, k, level));
 }
 
+struct btree_node_scrub {
+	struct bch_fs		*c;
+	struct bch_dev		*ca;
+	void			*buf;
+	bool			used_mempool;
+	unsigned		written;
+
+	enum btree_id		btree;
+	unsigned		level;
+	struct bkey_buf		key;
+	__le64			seq;
+
+	struct work_struct	work;
+	struct bio		bio;
+};
+
+static bool btree_node_scrub_check(struct bch_fs *c, struct btree_node *data, unsigned ptr_written,
+				   struct printbuf *err)
+{
+	unsigned written = 0;
+
+	if (le64_to_cpu(data->magic) != bset_magic(c)) {
+		prt_printf(err, "bad magic: want %llx, got %llx",
+			   bset_magic(c), le64_to_cpu(data->magic));
+		return false;
+	}
+
+	while (written < (ptr_written ?: btree_sectors(c))) {
+		struct btree_node_entry *bne;
+		struct bset *i;
+		bool first = !written;
+
+		if (first) {
+			bne = NULL;
+			i = &data->keys;
+		} else {
+			bne = (void *) data + (written << 9);
+			i = &bne->keys;
+
+			if (!ptr_written && i->seq != data->keys.seq)
+				break;
+		}
+
+		struct nonce nonce = btree_nonce(i, written << 9);
+		bool good_csum_type = bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i));
+
+		if (first) {
+			if (good_csum_type) {
+				struct bch_csum csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, data);
+				if (bch2_crc_cmp(data->csum, csum)) {
+					bch2_csum_err_msg(err, BSET_CSUM_TYPE(i), data->csum, csum);
+					return false;
+				}
+			}
+
+			written += vstruct_sectors(data, c->block_bits);
+		} else {
+			if (good_csum_type) {
+				struct bch_csum csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, bne);
+				if (bch2_crc_cmp(bne->csum, csum)) {
+					bch2_csum_err_msg(err, BSET_CSUM_TYPE(i), bne->csum, csum);
+					return false;
+				}
+			}
+
+			written += vstruct_sectors(bne, c->block_bits);
+		}
+	}
+
+	return true;
+}
+
+static void btree_node_scrub_work(struct work_struct *work)
+{
+	struct btree_node_scrub *scrub = container_of(work, struct btree_node_scrub, work);
+	struct bch_fs *c = scrub->c;
+	struct printbuf err = PRINTBUF;
+
+	__bch2_btree_pos_to_text(&err, c, scrub->btree, scrub->level,
+				 bkey_i_to_s_c(scrub->key.k));
+	prt_newline(&err);
+
+	if (!btree_node_scrub_check(c, scrub->buf, scrub->written, &err)) {
+		struct btree_trans *trans = bch2_trans_get(c);
+
+		struct btree_iter iter;
+		bch2_trans_node_iter_init(trans, &iter, scrub->btree,
+					  scrub->key.k->k.p, 0, scrub->level - 1, 0);
+
+		struct btree *b;
+		int ret = lockrestart_do(trans, PTR_ERR_OR_ZERO(b = bch2_btree_iter_peek_node(&iter)));
+		if (ret)
+			goto err;
+
+		if (bkey_i_to_btree_ptr_v2(&b->key)->v.seq == scrub->seq) {
+			bch_err(c, "error validating btree node during scrub on %s at btree %s",
+				scrub->ca->name, err.buf);
+
+			ret = bch2_btree_node_rewrite(trans, &iter, b, 0);
+		}
+err:
+		bch2_trans_iter_exit(trans, &iter);
+		bch2_trans_begin(trans);
+		bch2_trans_put(trans);
+	}
+
+	printbuf_exit(&err);
+	bch2_bkey_buf_exit(&scrub->key, c);;
+	btree_bounce_free(c, c->opts.btree_node_size, scrub->used_mempool, scrub->buf);
+	percpu_ref_put(&scrub->ca->io_ref);
+	kfree(scrub);
+	bch2_write_ref_put(c, BCH_WRITE_REF_btree_node_scrub);
+}
+
+static void btree_node_scrub_endio(struct bio *bio)
+{
+	struct btree_node_scrub *scrub = container_of(bio, struct btree_node_scrub, bio);
+
+	queue_work(scrub->c->btree_read_complete_wq, &scrub->work);
+}
+
+int bch2_btree_node_scrub(struct btree_trans *trans,
+			  enum btree_id btree, unsigned level,
+			  struct bkey_s_c k, unsigned dev)
+{
+	if (k.k->type != KEY_TYPE_btree_ptr_v2)
+		return 0;
+
+	struct bch_fs *c = trans->c;
+
+	if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_btree_node_scrub))
+		return -BCH_ERR_erofs_no_writes;
+
+	struct extent_ptr_decoded pick;
+	int ret = bch2_bkey_pick_read_device(c, k, NULL, &pick, dev);
+	if (ret <= 0)
+		goto err;
+
+	struct bch_dev *ca = bch2_dev_get_ioref(c, pick.ptr.dev, READ);
+	if (!ca) {
+		ret = -BCH_ERR_device_offline;
+		goto err;
+	}
+
+	bool used_mempool = false;
+	void *buf = btree_bounce_alloc(c, c->opts.btree_node_size, &used_mempool);
+
+	unsigned vecs = buf_pages(buf, c->opts.btree_node_size);
+
+	struct btree_node_scrub *scrub =
+		kzalloc(sizeof(*scrub) + sizeof(struct bio_vec) * vecs, GFP_KERNEL);
+	if (!scrub) {
+		ret = -ENOMEM;
+		goto err_free;
+	}
+
+	scrub->c		= c;
+	scrub->ca		= ca;
+	scrub->buf		= buf;
+	scrub->used_mempool	= used_mempool;
+	scrub->written		= btree_ptr_sectors_written(k);
+
+	scrub->btree		= btree;
+	scrub->level		= level;
+	bch2_bkey_buf_init(&scrub->key);
+	bch2_bkey_buf_reassemble(&scrub->key, c, k);
+	scrub->seq		= bkey_s_c_to_btree_ptr_v2(k).v->seq;
+
+	INIT_WORK(&scrub->work, btree_node_scrub_work);
+
+	bio_init(&scrub->bio, ca->disk_sb.bdev, scrub->bio.bi_inline_vecs, vecs, REQ_OP_READ);
+	bch2_bio_map(&scrub->bio, scrub->buf, c->opts.btree_node_size);
+	scrub->bio.bi_iter.bi_sector	= pick.ptr.offset;
+	scrub->bio.bi_end_io		= btree_node_scrub_endio;
+	submit_bio(&scrub->bio);
+	return 0;
+err_free:
+	btree_bounce_free(c, c->opts.btree_node_size, used_mempool, buf);
+	percpu_ref_put(&ca->io_ref);
+err:
+	bch2_write_ref_put(c, BCH_WRITE_REF_btree_node_scrub);
+	return ret;
+}
+
 static void bch2_btree_complete_write(struct bch_fs *c, struct btree *b,
 				      struct btree_write *w)
 {
@@ -1831,7 +2021,7 @@ static void bch2_btree_complete_write(struct bch_fs *c, struct btree *b,
 	bch2_journal_pin_drop(&c->journal, &w->journal);
 }
 
-static void __btree_node_write_done(struct bch_fs *c, struct btree *b)
+static void __btree_node_write_done(struct bch_fs *c, struct btree *b, u64 start_time)
 {
 	struct btree_write *w = btree_prev_write(b);
 	unsigned long old, new;
@@ -1839,6 +2029,9 @@ static void __btree_node_write_done(struct bch_fs *c, struct btree *b)
 
 	bch2_btree_complete_write(c, b, w);
 
+	if (start_time)
+		bch2_time_stats_update(&c->times[BCH_TIME_btree_node_write], start_time);
+
 	old = READ_ONCE(b->flags);
 	do {
 		new = old;
@@ -1869,7 +2062,7 @@ static void __btree_node_write_done(struct bch_fs *c, struct btree *b)
 		wake_up_bit(&b->flags, BTREE_NODE_write_in_flight);
 }
 
-static void btree_node_write_done(struct bch_fs *c, struct btree *b)
+static void btree_node_write_done(struct bch_fs *c, struct btree *b, u64 start_time)
 {
 	struct btree_trans *trans = bch2_trans_get(c);
 
@@ -1877,7 +2070,7 @@ static void btree_node_write_done(struct bch_fs *c, struct btree *b)
 
 	/* we don't need transaction context anymore after we got the lock. */
 	bch2_trans_put(trans);
-	__btree_node_write_done(c, b);
+	__btree_node_write_done(c, b, start_time);
 	six_unlock_read(&b->c.lock);
 }
 
@@ -1887,6 +2080,7 @@ static void btree_node_write_work(struct work_struct *work)
 		container_of(work, struct btree_write_bio, work);
 	struct bch_fs *c	= wbio->wbio.c;
 	struct btree *b		= wbio->wbio.bio.bi_private;
+	u64 start_time		= wbio->start_time;
 	int ret = 0;
 
 	btree_bounce_free(c,
@@ -1919,12 +2113,18 @@ static void btree_node_write_work(struct work_struct *work)
 	}
 out:
 	bio_put(&wbio->wbio.bio);
-	btree_node_write_done(c, b);
+	btree_node_write_done(c, b, start_time);
 	return;
 err:
 	set_btree_node_noevict(b);
-	bch2_fs_fatal_err_on(!bch2_err_matches(ret, EROFS), c,
-			     "writing btree node: %s", bch2_err_str(ret));
+
+	if (!bch2_err_matches(ret, EROFS)) {
+		struct printbuf buf = PRINTBUF;
+		prt_printf(&buf, "writing btree node: %s\n  ", bch2_err_str(ret));
+		bch2_btree_pos_to_text(&buf, c, b);
+		bch2_fs_fatal_error(c, "%s", buf.buf);
+		printbuf_exit(&buf);
+	}
 	goto out;
 }
 
@@ -1937,16 +2137,21 @@ static void btree_node_write_endio(struct bio *bio)
 	struct bch_fs *c		= wbio->c;
 	struct btree *b			= wbio->bio.bi_private;
 	struct bch_dev *ca		= wbio->have_ioref ? bch2_dev_have_ref(c, wbio->dev) : NULL;
-	unsigned long flags;
 
-	if (wbio->have_ioref)
-		bch2_latency_acct(ca, wbio->submit_time, WRITE);
+	bch2_account_io_completion(ca, BCH_MEMBER_ERROR_write,
+				   wbio->submit_time, !bio->bi_status);
 
-	if (!ca ||
-	    bch2_dev_io_err_on(bio->bi_status, ca, BCH_MEMBER_ERROR_write,
-			       "btree write error: %s",
-			       bch2_blk_status_to_str(bio->bi_status)) ||
-	    bch2_meta_write_fault("btree")) {
+	if (ca && bio->bi_status) {
+		struct printbuf buf = PRINTBUF;
+		prt_printf(&buf, "btree write error: %s\n  ",
+			   bch2_blk_status_to_str(bio->bi_status));
+		bch2_btree_pos_to_text(&buf, c, b);
+		bch_err_dev_ratelimited(ca, "%s", buf.buf);
+		printbuf_exit(&buf);
+	}
+
+	if (bio->bi_status) {
+		unsigned long flags;
 		spin_lock_irqsave(&c->btree_write_error_lock, flags);
 		bch2_dev_list_add_dev(&orig->failed, wbio->dev);
 		spin_unlock_irqrestore(&c->btree_write_error_lock, flags);
@@ -2023,6 +2228,7 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, unsigned flags)
 	bool validate_before_checksum = false;
 	enum btree_write_type type = flags & BTREE_WRITE_TYPE_MASK;
 	void *data;
+	u64 start_time = local_clock();
 	int ret;
 
 	if (flags & BTREE_WRITE_ALREADY_STARTED)
@@ -2231,6 +2437,7 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, unsigned flags)
 	wbio->data			= data;
 	wbio->data_bytes		= bytes;
 	wbio->sector_offset		= b->written;
+	wbio->start_time		= start_time;
 	wbio->wbio.c			= c;
 	wbio->wbio.used_mempool		= used_mempool;
 	wbio->wbio.first_btree_write	= !b->written;
@@ -2258,7 +2465,7 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, unsigned flags)
 	b->written += sectors_to_write;
 nowrite:
 	btree_bounce_free(c, bytes, used_mempool, data);
-	__btree_node_write_done(c, b);
+	__btree_node_write_done(c, b, 0);
 }
 
 /*
diff --git a/fs/bcachefs/btree_io.h b/fs/bcachefs/btree_io.h
index 6f9e4a6dacf7..dbf76d22c660 100644
--- a/fs/bcachefs/btree_io.h
+++ b/fs/bcachefs/btree_io.h
@@ -52,6 +52,7 @@ struct btree_write_bio {
 	void			*data;
 	unsigned		data_bytes;
 	unsigned		sector_offset;
+	u64			start_time;
 	struct bch_write_bio	wbio;
 };
 
@@ -132,6 +133,9 @@ void bch2_btree_node_read(struct btree_trans *, struct btree *, bool);
 int bch2_btree_root_read(struct bch_fs *, enum btree_id,
 			 const struct bkey_i *, unsigned);
 
+int bch2_btree_node_scrub(struct btree_trans *, enum btree_id, unsigned,
+			  struct bkey_s_c, unsigned);
+
 bool bch2_btree_post_write_cleanup(struct bch_fs *, struct btree *);
 
 enum btree_write_flags {
diff --git a/fs/bcachefs/btree_iter.c b/fs/bcachefs/btree_iter.c
index e32fce4fd258..7542c6f9c88e 100644
--- a/fs/bcachefs/btree_iter.c
+++ b/fs/bcachefs/btree_iter.c
@@ -562,20 +562,6 @@ static inline struct bkey_s_c btree_path_level_peek_all(struct bch_fs *c,
 			bch2_btree_node_iter_peek_all(&l->iter, l->b));
 }
 
-static inline struct bkey_s_c btree_path_level_peek(struct btree_trans *trans,
-						    struct btree_path *path,
-						    struct btree_path_level *l,
-						    struct bkey *u)
-{
-	struct bkey_s_c k = __btree_iter_unpack(trans->c, l, u,
-			bch2_btree_node_iter_peek(&l->iter, l->b));
-
-	path->pos = k.k ? k.k->p : l->b->key.k.p;
-	trans->paths_sorted = false;
-	bch2_btree_path_verify_level(trans, path, l - path->l);
-	return k;
-}
-
 static inline struct bkey_s_c btree_path_level_prev(struct btree_trans *trans,
 						    struct btree_path *path,
 						    struct btree_path_level *l,
diff --git a/fs/bcachefs/btree_iter.h b/fs/bcachefs/btree_iter.h
index b96157f3dc9c..8823eec6b284 100644
--- a/fs/bcachefs/btree_iter.h
+++ b/fs/bcachefs/btree_iter.h
@@ -335,13 +335,20 @@ static inline void bch2_trans_verify_not_unlocked_or_in_restart(struct btree_tra
 }
 
 __always_inline
-static int btree_trans_restart_ip(struct btree_trans *trans, int err, unsigned long ip)
+static int btree_trans_restart_foreign_task(struct btree_trans *trans, int err, unsigned long ip)
 {
 	BUG_ON(err <= 0);
 	BUG_ON(!bch2_err_matches(-err, BCH_ERR_transaction_restart));
 
 	trans->restarted = err;
 	trans->last_restarted_ip = ip;
+	return -err;
+}
+
+__always_inline
+static int btree_trans_restart_ip(struct btree_trans *trans, int err, unsigned long ip)
+{
+	btree_trans_restart_foreign_task(trans, err, ip);
 #ifdef CONFIG_BCACHEFS_DEBUG
 	darray_exit(&trans->last_restarted_trace);
 	bch2_save_backtrace(&trans->last_restarted_trace, current, 0, GFP_NOWAIT);
diff --git a/fs/bcachefs/btree_locking.c b/fs/bcachefs/btree_locking.c
index caef65adeae4..94eb2b73a843 100644
--- a/fs/bcachefs/btree_locking.c
+++ b/fs/bcachefs/btree_locking.c
@@ -91,10 +91,10 @@ static noinline void print_chain(struct printbuf *out, struct lock_graph *g)
 	struct trans_waiting_for_lock *i;
 
 	for (i = g->g; i != g->g + g->nr; i++) {
-		struct task_struct *task = i->trans->locking_wait.task;
+		struct task_struct *task = READ_ONCE(i->trans->locking_wait.task);
 		if (i != g->g)
 			prt_str(out, "<- ");
-		prt_printf(out, "%u ", task ?task->pid : 0);
+		prt_printf(out, "%u ", task ? task->pid : 0);
 	}
 	prt_newline(out);
 }
@@ -172,7 +172,9 @@ static int abort_lock(struct lock_graph *g, struct trans_waiting_for_lock *i)
 {
 	if (i == g->g) {
 		trace_would_deadlock(g, i->trans);
-		return btree_trans_restart(i->trans, BCH_ERR_transaction_restart_would_deadlock);
+		return btree_trans_restart_foreign_task(i->trans,
+					BCH_ERR_transaction_restart_would_deadlock,
+					_THIS_IP_);
 	} else {
 		i->trans->lock_must_abort = true;
 		wake_up_process(i->trans->locking_wait.task);
diff --git a/fs/bcachefs/btree_node_scan.c b/fs/bcachefs/btree_node_scan.c
index a7f06deee13c..678161321e42 100644
--- a/fs/bcachefs/btree_node_scan.c
+++ b/fs/bcachefs/btree_node_scan.c
@@ -166,11 +166,17 @@ static void try_read_btree_node(struct find_btree_nodes *f, struct bch_dev *ca,
 	bio->bi_iter.bi_sector	= offset;
 	bch2_bio_map(bio, bn, PAGE_SIZE);
 
+	u64 submit_time = local_clock();
 	submit_bio_wait(bio);
-	if (bch2_dev_io_err_on(bio->bi_status, ca, BCH_MEMBER_ERROR_read,
-			       "IO error in try_read_btree_node() at %llu: %s",
-			       offset, bch2_blk_status_to_str(bio->bi_status)))
+
+	bch2_account_io_completion(ca, BCH_MEMBER_ERROR_read, submit_time, !bio->bi_status);
+
+	if (bio->bi_status) {
+		bch_err_dev_ratelimited(ca,
+				"IO error in try_read_btree_node() at %llu: %s",
+				offset, bch2_blk_status_to_str(bio->bi_status));
 		return;
+	}
 
 	if (le64_to_cpu(bn->magic) != bset_magic(c))
 		return;
@@ -264,7 +270,7 @@ static int read_btree_nodes_worker(void *p)
 err:
 	bio_put(bio);
 	free_page((unsigned long) buf);
-	percpu_ref_get(&ca->io_ref);
+	percpu_ref_put(&ca->io_ref);
 	closure_put(w->cl);
 	kfree(w);
 	return 0;
@@ -283,29 +289,28 @@ static int read_btree_nodes(struct find_btree_nodes *f)
 			continue;
 
 		struct find_btree_nodes_worker *w = kmalloc(sizeof(*w), GFP_KERNEL);
-		struct task_struct *t;
-
 		if (!w) {
 			percpu_ref_put(&ca->io_ref);
 			ret = -ENOMEM;
 			goto err;
 		}
 
-		percpu_ref_get(&ca->io_ref);
-		closure_get(&cl);
 		w->cl		= &cl;
 		w->f		= f;
 		w->ca		= ca;
 
-		t = kthread_run(read_btree_nodes_worker, w, "read_btree_nodes/%s", ca->name);
+		struct task_struct *t = kthread_create(read_btree_nodes_worker, w, "read_btree_nodes/%s", ca->name);
 		ret = PTR_ERR_OR_ZERO(t);
 		if (ret) {
 			percpu_ref_put(&ca->io_ref);
-			closure_put(&cl);
-			f->ret = ret;
-			bch_err(c, "error starting kthread: %i", ret);
+			kfree(w);
+			bch_err_msg(c, ret, "starting kthread");
 			break;
 		}
+
+		closure_get(&cl);
+		percpu_ref_get(&ca->io_ref);
+		wake_up_process(t);
 	}
 err:
 	closure_sync(&cl);
diff --git a/fs/bcachefs/btree_trans_commit.c b/fs/bcachefs/btree_trans_commit.c
index c4f524b2ca9a..7d7e52ddde02 100644
--- a/fs/bcachefs/btree_trans_commit.c
+++ b/fs/bcachefs/btree_trans_commit.c
@@ -164,6 +164,7 @@ bool bch2_btree_bset_insert_key(struct btree_trans *trans,
 	EBUG_ON(bpos_gt(insert->k.p, b->data->max_key));
 	EBUG_ON(insert->k.u64s > bch2_btree_keys_u64s_remaining(b));
 	EBUG_ON(!b->c.level && !bpos_eq(insert->k.p, path->pos));
+	kmsan_check_memory(insert, bkey_bytes(&insert->k));
 
 	k = bch2_btree_node_iter_peek_all(node_iter, b);
 	if (k && bkey_cmp_left_packed(b, k, &insert->k.p))
@@ -336,6 +337,7 @@ static inline void btree_insert_entry_checks(struct btree_trans *trans,
 	BUG_ON(i->cached	!= path->cached);
 	BUG_ON(i->level		!= path->level);
 	BUG_ON(i->btree_id	!= path->btree_id);
+	BUG_ON(i->bkey_type	!= __btree_node_type(path->level, path->btree_id));
 	EBUG_ON(!i->level &&
 		btree_type_has_snapshots(i->btree_id) &&
 		!(i->flags & BTREE_UPDATE_internal_snapshot_node) &&
@@ -517,69 +519,45 @@ static int run_one_trans_trigger(struct btree_trans *trans, struct btree_insert_
 	}
 }
 
-static int run_btree_triggers(struct btree_trans *trans, enum btree_id btree_id,
-			      unsigned *btree_id_updates_start)
+static int bch2_trans_commit_run_triggers(struct btree_trans *trans)
 {
-	bool trans_trigger_run;
+	unsigned sort_id_start = 0;
 
-	/*
-	 * Running triggers will append more updates to the list of updates as
-	 * we're walking it:
-	 */
-	do {
-		trans_trigger_run = false;
+	while (sort_id_start < trans->nr_updates) {
+		unsigned i, sort_id = trans->updates[sort_id_start].sort_order;
+		bool trans_trigger_run;
 
-		for (unsigned i = *btree_id_updates_start;
-		     i < trans->nr_updates && trans->updates[i].btree_id <= btree_id;
-		     i++) {
-			if (trans->updates[i].btree_id < btree_id) {
-				*btree_id_updates_start = i;
-				continue;
+		/*
+		 * For a given btree, this algorithm runs insert triggers before
+		 * overwrite triggers: this is so that when extents are being
+		 * moved (e.g. by FALLOCATE_FL_INSERT_RANGE), we don't drop
+		 * references before they are re-added.
+		 *
+		 * Running triggers will append more updates to the list of
+		 * updates as we're walking it:
+		 */
+		do {
+			trans_trigger_run = false;
+
+			for (i = sort_id_start;
+			     i < trans->nr_updates && trans->updates[i].sort_order <= sort_id;
+			     i++) {
+				if (trans->updates[i].sort_order < sort_id) {
+					sort_id_start = i;
+					continue;
+				}
+
+				int ret = run_one_trans_trigger(trans, trans->updates + i);
+				if (ret < 0)
+					return ret;
+				if (ret)
+					trans_trigger_run = true;
 			}
+		} while (trans_trigger_run);
 
-			int ret = run_one_trans_trigger(trans, trans->updates + i);
-			if (ret < 0)
-				return ret;
-			if (ret)
-				trans_trigger_run = true;
-		}
-	} while (trans_trigger_run);
-
-	trans_for_each_update(trans, i)
-		BUG_ON(!(i->flags & BTREE_TRIGGER_norun) &&
-		       i->btree_id == btree_id &&
-		       btree_node_type_has_trans_triggers(i->bkey_type) &&
-		       (!i->insert_trigger_run || !i->overwrite_trigger_run));
-
-	return 0;
-}
-
-static int bch2_trans_commit_run_triggers(struct btree_trans *trans)
-{
-	unsigned btree_id = 0, btree_id_updates_start = 0;
-	int ret = 0;
-
-	/*
-	 *
-	 * For a given btree, this algorithm runs insert triggers before
-	 * overwrite triggers: this is so that when extents are being moved
-	 * (e.g. by FALLOCATE_FL_INSERT_RANGE), we don't drop references before
-	 * they are re-added.
-	 */
-	for (btree_id = 0; btree_id < BTREE_ID_NR; btree_id++) {
-		if (btree_id == BTREE_ID_alloc)
-			continue;
-
-		ret = run_btree_triggers(trans, btree_id, &btree_id_updates_start);
-		if (ret)
-			return ret;
+		sort_id_start = i;
 	}
 
-	btree_id_updates_start = 0;
-	ret = run_btree_triggers(trans, BTREE_ID_alloc, &btree_id_updates_start);
-	if (ret)
-		return ret;
-
 #ifdef CONFIG_BCACHEFS_DEBUG
 	trans_for_each_update(trans, i)
 		BUG_ON(!(i->flags & BTREE_TRIGGER_norun) &&
@@ -903,18 +881,7 @@ int bch2_trans_commit_error(struct btree_trans *trans, unsigned flags,
 	struct bch_fs *c = trans->c;
 	enum bch_watermark watermark = flags & BCH_WATERMARK_MASK;
 
-	switch (ret) {
-	case -BCH_ERR_btree_insert_btree_node_full:
-		ret = bch2_btree_split_leaf(trans, i->path, flags);
-		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
-			trace_and_count(c, trans_restart_btree_node_split, trans,
-					trace_ip, trans->paths + i->path);
-		break;
-	case -BCH_ERR_btree_insert_need_mark_replicas:
-		ret = drop_locks_do(trans,
-			bch2_accounting_update_sb(trans));
-		break;
-	case -BCH_ERR_journal_res_get_blocked:
+	if (bch2_err_matches(ret, BCH_ERR_journal_res_blocked)) {
 		/*
 		 * XXX: this should probably be a separate BTREE_INSERT_NONBLOCK
 		 * flag
@@ -922,13 +889,26 @@ int bch2_trans_commit_error(struct btree_trans *trans, unsigned flags,
 		if ((flags & BCH_TRANS_COMMIT_journal_reclaim) &&
 		    watermark < BCH_WATERMARK_reclaim) {
 			ret = -BCH_ERR_journal_reclaim_would_deadlock;
-			break;
+			goto out;
 		}
 
 		ret = drop_locks_do(trans,
 			bch2_trans_journal_res_get(trans,
 					(flags & BCH_WATERMARK_MASK)|
 					JOURNAL_RES_GET_CHECK));
+		goto out;
+	}
+
+	switch (ret) {
+	case -BCH_ERR_btree_insert_btree_node_full:
+		ret = bch2_btree_split_leaf(trans, i->path, flags);
+		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
+			trace_and_count(c, trans_restart_btree_node_split, trans,
+					trace_ip, trans->paths + i->path);
+		break;
+	case -BCH_ERR_btree_insert_need_mark_replicas:
+		ret = drop_locks_do(trans,
+			bch2_accounting_update_sb(trans));
 		break;
 	case -BCH_ERR_btree_insert_need_journal_reclaim:
 		bch2_trans_unlock(trans);
@@ -950,7 +930,7 @@ int bch2_trans_commit_error(struct btree_trans *trans, unsigned flags,
 		BUG_ON(ret >= 0);
 		break;
 	}
-
+out:
 	BUG_ON(bch2_err_matches(ret, BCH_ERR_transaction_restart) != !!trans->restarted);
 
 	bch2_fs_inconsistent_on(bch2_err_matches(ret, ENOSPC) &&
diff --git a/fs/bcachefs/btree_types.h b/fs/bcachefs/btree_types.h
index a09cbe9cd94f..77578da2d23f 100644
--- a/fs/bcachefs/btree_types.h
+++ b/fs/bcachefs/btree_types.h
@@ -423,6 +423,7 @@ static inline struct bpos btree_node_pos(struct btree_bkey_cached_common *b)
 
 struct btree_insert_entry {
 	unsigned		flags;
+	u8			sort_order;
 	u8			bkey_type;
 	enum btree_id		btree_id:8;
 	u8			level:4;
@@ -853,6 +854,18 @@ static inline bool btree_type_uses_write_buffer(enum btree_id btree)
 	return BIT_ULL(btree) & mask;
 }
 
+static inline u8 btree_trigger_order(enum btree_id btree)
+{
+	switch (btree) {
+	case BTREE_ID_alloc:
+		return U8_MAX;
+	case BTREE_ID_stripes:
+		return U8_MAX - 1;
+	default:
+		return btree;
+	}
+}
+
 struct btree_root {
 	struct btree		*b;
 
diff --git a/fs/bcachefs/btree_update.c b/fs/bcachefs/btree_update.c
index 13d794f201a5..bd2eb42edb24 100644
--- a/fs/bcachefs/btree_update.c
+++ b/fs/bcachefs/btree_update.c
@@ -17,7 +17,7 @@
 static inline int btree_insert_entry_cmp(const struct btree_insert_entry *l,
 					 const struct btree_insert_entry *r)
 {
-	return   cmp_int(l->btree_id,	r->btree_id) ?:
+	return   cmp_int(l->sort_order,	r->sort_order) ?:
 		 cmp_int(l->cached,	r->cached) ?:
 		 -cmp_int(l->level,	r->level) ?:
 		 bpos_cmp(l->k->k.p,	r->k->k.p);
@@ -397,6 +397,7 @@ bch2_trans_update_by_path(struct btree_trans *trans, btree_path_idx_t path_idx,
 
 	n = (struct btree_insert_entry) {
 		.flags		= flags,
+		.sort_order	= btree_trigger_order(path->btree_id),
 		.bkey_type	= __btree_node_type(path->level, path->btree_id),
 		.btree_id	= path->btree_id,
 		.level		= path->level,
@@ -511,6 +512,8 @@ static noinline int bch2_trans_update_get_key_cache(struct btree_trans *trans,
 int __must_check bch2_trans_update(struct btree_trans *trans, struct btree_iter *iter,
 				   struct bkey_i *k, enum btree_iter_update_trigger_flags flags)
 {
+	kmsan_check_memory(k, bkey_bytes(&k->k));
+
 	btree_path_idx_t path_idx = iter->update_path ?: iter->path;
 	int ret;
 
diff --git a/fs/bcachefs/btree_update.h b/fs/bcachefs/btree_update.h
index 47d8690f01bf..d2e1c04353f6 100644
--- a/fs/bcachefs/btree_update.h
+++ b/fs/bcachefs/btree_update.h
@@ -133,6 +133,8 @@ static inline int __must_check bch2_trans_update_buffered(struct btree_trans *tr
 					    enum btree_id btree,
 					    struct bkey_i *k)
 {
+	kmsan_check_memory(k, bkey_bytes(&k->k));
+
 	if (unlikely(!btree_type_uses_write_buffer(btree))) {
 		int ret = bch2_btree_write_buffer_insert_err(trans, btree, k);
 		dump_stack();
diff --git a/fs/bcachefs/btree_update_interior.c b/fs/bcachefs/btree_update_interior.c
index e4e7c804625e..67f1e3202835 100644
--- a/fs/bcachefs/btree_update_interior.c
+++ b/fs/bcachefs/btree_update_interior.c
@@ -649,6 +649,14 @@ static int btree_update_nodes_written_trans(struct btree_trans *trans,
 	return 0;
 }
 
+/* If the node has been reused, we might be reading uninitialized memory - that's fine: */
+static noinline __no_kmsan_checks bool btree_node_seq_matches(struct btree *b, __le64 seq)
+{
+	struct btree_node *b_data = READ_ONCE(b->data);
+
+	return (b_data ? b_data->keys.seq : 0) == seq;
+}
+
 static void btree_update_nodes_written(struct btree_update *as)
 {
 	struct bch_fs *c = as->c;
@@ -677,17 +685,9 @@ static void btree_update_nodes_written(struct btree_update *as)
 	 * on disk:
 	 */
 	for (i = 0; i < as->nr_old_nodes; i++) {
-		__le64 seq;
-
 		b = as->old_nodes[i];
 
-		bch2_trans_begin(trans);
-		btree_node_lock_nopath_nofail(trans, &b->c, SIX_LOCK_read);
-		seq = b->data ? b->data->keys.seq : 0;
-		six_unlock_read(&b->c.lock);
-		bch2_trans_unlock_long(trans);
-
-		if (seq == as->old_nodes_seq[i])
+		if (btree_node_seq_matches(b, as->old_nodes_seq[i]))
 			wait_on_bit_io(&b->flags, BTREE_NODE_write_in_flight_inner,
 				       TASK_UNINTERRUPTIBLE);
 	}
@@ -2126,6 +2126,31 @@ int __bch2_foreground_maybe_merge(struct btree_trans *trans,
 	goto out;
 }
 
+static int get_iter_to_node(struct btree_trans *trans, struct btree_iter *iter,
+			    struct btree *b)
+{
+	bch2_trans_node_iter_init(trans, iter, b->c.btree_id, b->key.k.p,
+				  BTREE_MAX_DEPTH, b->c.level,
+				  BTREE_ITER_intent);
+	int ret = bch2_btree_iter_traverse(iter);
+	if (ret)
+		goto err;
+
+	/* has node been freed? */
+	if (btree_iter_path(trans, iter)->l[b->c.level].b != b) {
+		/* node has been freed: */
+		BUG_ON(!btree_node_dying(b));
+		ret = -BCH_ERR_btree_node_dying;
+		goto err;
+	}
+
+	BUG_ON(!btree_node_hashed(b));
+	return 0;
+err:
+	bch2_trans_iter_exit(trans, iter);
+	return ret;
+}
+
 int bch2_btree_node_rewrite(struct btree_trans *trans,
 			    struct btree_iter *iter,
 			    struct btree *b,
@@ -2191,66 +2216,78 @@ int bch2_btree_node_rewrite(struct btree_trans *trans,
 	goto out;
 }
 
-struct async_btree_rewrite {
-	struct bch_fs		*c;
-	struct work_struct	work;
-	struct list_head	list;
-	enum btree_id		btree_id;
-	unsigned		level;
-	struct bkey_buf		key;
-};
-
-static int async_btree_node_rewrite_trans(struct btree_trans *trans,
-					  struct async_btree_rewrite *a)
+static int bch2_btree_node_rewrite_key(struct btree_trans *trans,
+				       enum btree_id btree, unsigned level,
+				       struct bkey_i *k, unsigned flags)
 {
 	struct btree_iter iter;
 	bch2_trans_node_iter_init(trans, &iter,
-				  a->btree_id, a->key.k->k.p,
-				  BTREE_MAX_DEPTH, a->level, 0);
+				  btree, k->k.p,
+				  BTREE_MAX_DEPTH, level, 0);
 	struct btree *b = bch2_btree_iter_peek_node(&iter);
 	int ret = PTR_ERR_OR_ZERO(b);
 	if (ret)
 		goto out;
 
-	bool found = b && btree_ptr_hash_val(&b->key) == btree_ptr_hash_val(a->key.k);
+	bool found = b && btree_ptr_hash_val(&b->key) == btree_ptr_hash_val(k);
 	ret = found
-		? bch2_btree_node_rewrite(trans, &iter, b, 0)
+		? bch2_btree_node_rewrite(trans, &iter, b, flags)
 		: -ENOENT;
+out:
+	bch2_trans_iter_exit(trans, &iter);
+	return ret;
+}
 
-#if 0
-	/* Tracepoint... */
-	if (!ret || ret == -ENOENT) {
-		struct bch_fs *c = trans->c;
-		struct printbuf buf = PRINTBUF;
+int bch2_btree_node_rewrite_pos(struct btree_trans *trans,
+				enum btree_id btree, unsigned level,
+				struct bpos pos, unsigned flags)
+{
+	BUG_ON(!level);
 
-		if (!ret) {
-			prt_printf(&buf, "rewrite node:\n  ");
-			bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(a->key.k));
-		} else {
-			prt_printf(&buf, "node to rewrite not found:\n  want: ");
-			bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(a->key.k));
-			prt_printf(&buf, "\n  got:  ");
-			if (b)
-				bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key));
-			else
-				prt_str(&buf, "(null)");
-		}
-		bch_info(c, "%s", buf.buf);
-		printbuf_exit(&buf);
-	}
-#endif
-out:
+	/* Traverse one depth lower to get a pointer to the node itself: */
+	struct btree_iter iter;
+	bch2_trans_node_iter_init(trans, &iter, btree, pos, 0, level - 1, 0);
+	struct btree *b = bch2_btree_iter_peek_node(&iter);
+	int ret = PTR_ERR_OR_ZERO(b);
+	if (ret)
+		goto err;
+
+	ret = bch2_btree_node_rewrite(trans, &iter, b, flags);
+err:
 	bch2_trans_iter_exit(trans, &iter);
 	return ret;
 }
 
+int bch2_btree_node_rewrite_key_get_iter(struct btree_trans *trans,
+					 struct btree *b, unsigned flags)
+{
+	struct btree_iter iter;
+	int ret = get_iter_to_node(trans, &iter, b);
+	if (ret)
+		return ret == -BCH_ERR_btree_node_dying ? 0 : ret;
+
+	ret = bch2_btree_node_rewrite(trans, &iter, b, flags);
+	bch2_trans_iter_exit(trans, &iter);
+	return ret;
+}
+
+struct async_btree_rewrite {
+	struct bch_fs		*c;
+	struct work_struct	work;
+	struct list_head	list;
+	enum btree_id		btree_id;
+	unsigned		level;
+	struct bkey_buf		key;
+};
+
 static void async_btree_node_rewrite_work(struct work_struct *work)
 {
 	struct async_btree_rewrite *a =
 		container_of(work, struct async_btree_rewrite, work);
 	struct bch_fs *c = a->c;
 
-	int ret = bch2_trans_do(c, async_btree_node_rewrite_trans(trans, a));
+	int ret = bch2_trans_do(c, bch2_btree_node_rewrite_key(trans,
+						a->btree_id, a->level, a->key.k, 0));
 	if (ret != -ENOENT)
 		bch_err_fn_ratelimited(c, ret);
 
@@ -2494,30 +2531,15 @@ int bch2_btree_node_update_key_get_iter(struct btree_trans *trans,
 					unsigned commit_flags, bool skip_triggers)
 {
 	struct btree_iter iter;
-	int ret;
-
-	bch2_trans_node_iter_init(trans, &iter, b->c.btree_id, b->key.k.p,
-				  BTREE_MAX_DEPTH, b->c.level,
-				  BTREE_ITER_intent);
-	ret = bch2_btree_iter_traverse(&iter);
+	int ret = get_iter_to_node(trans, &iter, b);
 	if (ret)
-		goto out;
-
-	/* has node been freed? */
-	if (btree_iter_path(trans, &iter)->l[b->c.level].b != b) {
-		/* node has been freed: */
-		BUG_ON(!btree_node_dying(b));
-		goto out;
-	}
-
-	BUG_ON(!btree_node_hashed(b));
+		return ret == -BCH_ERR_btree_node_dying ? 0 : ret;
 
 	bch2_bkey_drop_ptrs(bkey_i_to_s(new_key), ptr,
 			    !bch2_bkey_has_device(bkey_i_to_s(&b->key), ptr->dev));
 
 	ret = bch2_btree_node_update_key(trans, &iter, b, new_key,
 					 commit_flags, skip_triggers);
-out:
 	bch2_trans_iter_exit(trans, &iter);
 	return ret;
 }
diff --git a/fs/bcachefs/btree_update_interior.h b/fs/bcachefs/btree_update_interior.h
index 26d646e1275c..be71cd73b864 100644
--- a/fs/bcachefs/btree_update_interior.h
+++ b/fs/bcachefs/btree_update_interior.h
@@ -169,7 +169,14 @@ static inline int bch2_foreground_maybe_merge(struct btree_trans *trans,
 
 int bch2_btree_node_rewrite(struct btree_trans *, struct btree_iter *,
 			    struct btree *, unsigned);
+int bch2_btree_node_rewrite_pos(struct btree_trans *,
+				enum btree_id, unsigned,
+				struct bpos, unsigned);
+int bch2_btree_node_rewrite_key_get_iter(struct btree_trans *,
+					 struct btree *, unsigned);
+
 void bch2_btree_node_rewrite_async(struct bch_fs *, struct btree *);
+
 int bch2_btree_node_update_key(struct btree_trans *, struct btree_iter *,
 			       struct btree *, struct bkey_i *,
 			       unsigned, bool);
diff --git a/fs/bcachefs/buckets.c b/fs/bcachefs/buckets.c
index 345b117a4a4a..e56ef623ebc1 100644
--- a/fs/bcachefs/buckets.c
+++ b/fs/bcachefs/buckets.c
@@ -590,11 +590,9 @@ static int bch2_trigger_pointer(struct btree_trans *trans,
 		if (ret)
 			goto err;
 
-		if (!p.ptr.cached) {
-			ret = bch2_bucket_backpointer_mod(trans, k, &bp, insert);
-			if (ret)
-				goto err;
-		}
+		ret = bch2_bucket_backpointer_mod(trans, k, &bp, insert);
+		if (ret)
+			goto err;
 	}
 
 	if (flags & BTREE_TRIGGER_gc) {
@@ -674,10 +672,10 @@ static int bch2_trigger_stripe_ptr(struct btree_trans *trans,
 			return -BCH_ERR_ENOMEM_mark_stripe_ptr;
 		}
 
-		mutex_lock(&c->ec_stripes_heap_lock);
+		gc_stripe_lock(m);
 
 		if (!m || !m->alive) {
-			mutex_unlock(&c->ec_stripes_heap_lock);
+			gc_stripe_unlock(m);
 			struct printbuf buf = PRINTBUF;
 			bch2_bkey_val_to_text(&buf, c, k);
 			bch_err_ratelimited(c, "pointer to nonexistent stripe %llu\n  while marking %s",
@@ -693,7 +691,7 @@ static int bch2_trigger_stripe_ptr(struct btree_trans *trans,
 			.type = BCH_DISK_ACCOUNTING_replicas,
 		};
 		memcpy(&acc.replicas, &m->r.e, replicas_entry_bytes(&m->r.e));
-		mutex_unlock(&c->ec_stripes_heap_lock);
+		gc_stripe_unlock(m);
 
 		acc.replicas.data_type = data_type;
 		int ret = bch2_disk_accounting_mod(trans, &acc, &sectors, 1, true);
@@ -726,9 +724,7 @@ static int __trigger_extent(struct btree_trans *trans,
 		.replicas.nr_required	= 1,
 	};
 
-	struct disk_accounting_pos acct_compression_key = {
-		.type			= BCH_DISK_ACCOUNTING_compression,
-	};
+	unsigned cur_compression_type = 0;
 	u64 compression_acct[3] = { 1, 0, 0 };
 
 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
@@ -762,13 +758,13 @@ static int __trigger_extent(struct btree_trans *trans,
 			acc_replicas_key.replicas.nr_required = 0;
 		}
 
-		if (acct_compression_key.compression.type &&
-		    acct_compression_key.compression.type != p.crc.compression_type) {
+		if (cur_compression_type &&
+		    cur_compression_type != p.crc.compression_type) {
 			if (flags & BTREE_TRIGGER_overwrite)
 				bch2_u64s_neg(compression_acct, ARRAY_SIZE(compression_acct));
 
-			ret = bch2_disk_accounting_mod(trans, &acct_compression_key, compression_acct,
-						       ARRAY_SIZE(compression_acct), gc);
+			ret = bch2_disk_accounting_mod2(trans, gc, compression_acct,
+							compression, cur_compression_type);
 			if (ret)
 				return ret;
 
@@ -777,7 +773,7 @@ static int __trigger_extent(struct btree_trans *trans,
 			compression_acct[2] = 0;
 		}
 
-		acct_compression_key.compression.type = p.crc.compression_type;
+		cur_compression_type = p.crc.compression_type;
 		if (p.crc.compression_type) {
 			compression_acct[1] += p.crc.uncompressed_size;
 			compression_acct[2] += p.crc.compressed_size;
@@ -791,45 +787,34 @@ static int __trigger_extent(struct btree_trans *trans,
 	}
 
 	if (acc_replicas_key.replicas.nr_devs && !level && k.k->p.snapshot) {
-		struct disk_accounting_pos acc_snapshot_key = {
-			.type			= BCH_DISK_ACCOUNTING_snapshot,
-			.snapshot.id		= k.k->p.snapshot,
-		};
-		ret = bch2_disk_accounting_mod(trans, &acc_snapshot_key, replicas_sectors, 1, gc);
+		ret = bch2_disk_accounting_mod2_nr(trans, gc, replicas_sectors, 1, snapshot, k.k->p.snapshot);
 		if (ret)
 			return ret;
 	}
 
-	if (acct_compression_key.compression.type) {
+	if (cur_compression_type) {
 		if (flags & BTREE_TRIGGER_overwrite)
 			bch2_u64s_neg(compression_acct, ARRAY_SIZE(compression_acct));
 
-		ret = bch2_disk_accounting_mod(trans, &acct_compression_key, compression_acct,
-					       ARRAY_SIZE(compression_acct), gc);
+		ret = bch2_disk_accounting_mod2(trans, gc, compression_acct,
+						compression, cur_compression_type);
 		if (ret)
 			return ret;
 	}
 
 	if (level) {
-		struct disk_accounting_pos acc_btree_key = {
-			.type		= BCH_DISK_ACCOUNTING_btree,
-			.btree.id	= btree_id,
-		};
-		ret = bch2_disk_accounting_mod(trans, &acc_btree_key, replicas_sectors, 1, gc);
+		ret = bch2_disk_accounting_mod2_nr(trans, gc, replicas_sectors, 1, btree, btree_id);
 		if (ret)
 			return ret;
 	} else {
 		bool insert = !(flags & BTREE_TRIGGER_overwrite);
-		struct disk_accounting_pos acc_inum_key = {
-			.type		= BCH_DISK_ACCOUNTING_inum,
-			.inum.inum	= k.k->p.inode,
-		};
+
 		s64 v[3] = {
 			insert ? 1 : -1,
 			insert ? k.k->size : -((s64) k.k->size),
 			*replicas_sectors,
 		};
-		ret = bch2_disk_accounting_mod(trans, &acc_inum_key, v, ARRAY_SIZE(v), gc);
+		ret = bch2_disk_accounting_mod2(trans, gc, v, inum, k.k->p.inode);
 		if (ret)
 			return ret;
 	}
@@ -878,15 +863,15 @@ int bch2_trigger_extent(struct btree_trans *trans,
 		}
 
 		int need_rebalance_delta = 0;
-		s64 need_rebalance_sectors_delta = 0;
+		s64 need_rebalance_sectors_delta[1] = { 0 };
 
 		s64 s = bch2_bkey_sectors_need_rebalance(c, old);
 		need_rebalance_delta -= s != 0;
-		need_rebalance_sectors_delta -= s;
+		need_rebalance_sectors_delta[0] -= s;
 
 		s = bch2_bkey_sectors_need_rebalance(c, new.s_c);
 		need_rebalance_delta += s != 0;
-		need_rebalance_sectors_delta += s;
+		need_rebalance_sectors_delta[0] += s;
 
 		if ((flags & BTREE_TRIGGER_transactional) && need_rebalance_delta) {
 			int ret = bch2_btree_bit_mod_buffered(trans, BTREE_ID_rebalance_work,
@@ -895,12 +880,9 @@ int bch2_trigger_extent(struct btree_trans *trans,
 				return ret;
 		}
 
-		if (need_rebalance_sectors_delta) {
-			struct disk_accounting_pos acc = {
-				.type		= BCH_DISK_ACCOUNTING_rebalance_work,
-			};
-			int ret = bch2_disk_accounting_mod(trans, &acc, &need_rebalance_sectors_delta, 1,
-							   flags & BTREE_TRIGGER_gc);
+		if (need_rebalance_sectors_delta[0]) {
+			int ret = bch2_disk_accounting_mod2(trans, flags & BTREE_TRIGGER_gc,
+							    need_rebalance_sectors_delta, rebalance_work);
 			if (ret)
 				return ret;
 		}
@@ -916,17 +898,13 @@ static int __trigger_reservation(struct btree_trans *trans,
 			enum btree_iter_update_trigger_flags flags)
 {
 	if (flags & (BTREE_TRIGGER_transactional|BTREE_TRIGGER_gc)) {
-		s64 sectors = k.k->size;
+		s64 sectors[1] = { k.k->size };
 
 		if (flags & BTREE_TRIGGER_overwrite)
-			sectors = -sectors;
-
-		struct disk_accounting_pos acc = {
-			.type = BCH_DISK_ACCOUNTING_persistent_reserved,
-			.persistent_reserved.nr_replicas = bkey_s_c_to_reservation(k).v->nr_replicas,
-		};
+			sectors[0] = -sectors[0];
 
-		return bch2_disk_accounting_mod(trans, &acc, &sectors, 1, flags & BTREE_TRIGGER_gc);
+		return bch2_disk_accounting_mod2(trans, flags & BTREE_TRIGGER_gc, sectors,
+				persistent_reserved, bkey_s_c_to_reservation(k).v->nr_replicas);
 	}
 
 	return 0;
diff --git a/fs/bcachefs/buckets.h b/fs/bcachefs/buckets.h
index a9acdd6c0c86..c5363256e363 100644
--- a/fs/bcachefs/buckets.h
+++ b/fs/bcachefs/buckets.h
@@ -39,33 +39,6 @@ static inline u64 sector_to_bucket_and_offset(const struct bch_dev *ca, sector_t
 	for (_b = (_buckets)->b + (_buckets)->first_bucket;	\
 	     _b < (_buckets)->b + (_buckets)->nbuckets; _b++)
 
-/*
- * Ugly hack alert:
- *
- * We need to cram a spinlock in a single byte, because that's what we have left
- * in struct bucket, and we care about the size of these - during fsck, we need
- * in memory state for every single bucket on every device.
- *
- * We used to do
- *   while (xchg(&b->lock, 1) cpu_relax();
- * but, it turns out not all architectures support xchg on a single byte.
- *
- * So now we use bit_spin_lock(), with fun games since we can't burn a whole
- * ulong for this - we just need to make sure the lock bit always ends up in the
- * first byte.
- */
-
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-#define BUCKET_LOCK_BITNR	0
-#else
-#define BUCKET_LOCK_BITNR	(BITS_PER_LONG - 1)
-#endif
-
-union ulong_byte_assert {
-	ulong	ulong;
-	u8	byte;
-};
-
 static inline void bucket_unlock(struct bucket *b)
 {
 	BUILD_BUG_ON(!((union ulong_byte_assert) { .ulong = 1UL << BUCKET_LOCK_BITNR }).byte);
@@ -167,9 +140,7 @@ static inline int gen_cmp(u8 a, u8 b)
 
 static inline int gen_after(u8 a, u8 b)
 {
-	int r = gen_cmp(a, b);
-
-	return r > 0 ? r : 0;
+	return max(0, gen_cmp(a, b));
 }
 
 static inline int dev_ptr_stale_rcu(struct bch_dev *ca, const struct bch_extent_ptr *ptr)
diff --git a/fs/bcachefs/buckets_types.h b/fs/bcachefs/buckets_types.h
index 7174047b8e92..900b8680c8b5 100644
--- a/fs/bcachefs/buckets_types.h
+++ b/fs/bcachefs/buckets_types.h
@@ -7,6 +7,33 @@
 
 #define BUCKET_JOURNAL_SEQ_BITS		16
 
+/*
+ * Ugly hack alert:
+ *
+ * We need to cram a spinlock in a single byte, because that's what we have left
+ * in struct bucket, and we care about the size of these - during fsck, we need
+ * in memory state for every single bucket on every device.
+ *
+ * We used to do
+ *   while (xchg(&b->lock, 1) cpu_relax();
+ * but, it turns out not all architectures support xchg on a single byte.
+ *
+ * So now we use bit_spin_lock(), with fun games since we can't burn a whole
+ * ulong for this - we just need to make sure the lock bit always ends up in the
+ * first byte.
+ */
+
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+#define BUCKET_LOCK_BITNR	0
+#else
+#define BUCKET_LOCK_BITNR	(BITS_PER_LONG - 1)
+#endif
+
+union ulong_byte_assert {
+	ulong	ulong;
+	u8	byte;
+};
+
 struct bucket {
 	u8			lock;
 	u8			gen_valid:1;
diff --git a/fs/bcachefs/chardev.c b/fs/bcachefs/chardev.c
index 46e9e32105a9..57d55b3ddc71 100644
--- a/fs/bcachefs/chardev.c
+++ b/fs/bcachefs/chardev.c
@@ -11,6 +11,7 @@
 #include "move.h"
 #include "recovery_passes.h"
 #include "replicas.h"
+#include "sb-counters.h"
 #include "super-io.h"
 #include "thread_with_file.h"
 
@@ -312,7 +313,12 @@ static int bch2_data_thread(void *arg)
 	struct bch_data_ctx *ctx = container_of(arg, struct bch_data_ctx, thr);
 
 	ctx->thr.ret = bch2_data_job(ctx->c, &ctx->stats, ctx->arg);
-	ctx->stats.data_type = U8_MAX;
+	if (ctx->thr.ret == -BCH_ERR_device_offline)
+		ctx->stats.ret = BCH_IOCTL_DATA_EVENT_RET_device_offline;
+	else {
+		ctx->stats.ret = BCH_IOCTL_DATA_EVENT_RET_done;
+		ctx->stats.data_type = (int) DATA_PROGRESS_DATA_TYPE_done;
+	}
 	return 0;
 }
 
@@ -331,14 +337,30 @@ static ssize_t bch2_data_job_read(struct file *file, char __user *buf,
 	struct bch_data_ctx *ctx = container_of(file->private_data, struct bch_data_ctx, thr);
 	struct bch_fs *c = ctx->c;
 	struct bch_ioctl_data_event e = {
-		.type			= BCH_DATA_EVENT_PROGRESS,
-		.p.data_type		= ctx->stats.data_type,
-		.p.btree_id		= ctx->stats.pos.btree,
-		.p.pos			= ctx->stats.pos.pos,
-		.p.sectors_done		= atomic64_read(&ctx->stats.sectors_seen),
-		.p.sectors_total	= bch2_fs_usage_read_short(c).used,
+		.type				= BCH_DATA_EVENT_PROGRESS,
+		.ret				= ctx->stats.ret,
+		.p.data_type			= ctx->stats.data_type,
+		.p.btree_id			= ctx->stats.pos.btree,
+		.p.pos				= ctx->stats.pos.pos,
+		.p.sectors_done			= atomic64_read(&ctx->stats.sectors_seen),
+		.p.sectors_error_corrected	= atomic64_read(&ctx->stats.sectors_error_corrected),
+		.p.sectors_error_uncorrected	= atomic64_read(&ctx->stats.sectors_error_uncorrected),
 	};
 
+	if (ctx->arg.op == BCH_DATA_OP_scrub) {
+		struct bch_dev *ca = bch2_dev_tryget(c, ctx->arg.scrub.dev);
+		if (ca) {
+			struct bch_dev_usage u;
+			bch2_dev_usage_read_fast(ca, &u);
+			for (unsigned i = BCH_DATA_btree; i < ARRAY_SIZE(u.d); i++)
+				if (ctx->arg.scrub.data_types & BIT(i))
+					e.p.sectors_total += u.d[i].sectors;
+			bch2_dev_put(ca);
+		}
+	} else {
+		e.p.sectors_total	= bch2_fs_usage_read_short(c).used;
+	}
+
 	if (len < sizeof(e))
 		return -EINVAL;
 
@@ -710,6 +732,8 @@ long bch2_fs_ioctl(struct bch_fs *c, unsigned cmd, void __user *arg)
 		BCH_IOCTL(fsck_online, struct bch_ioctl_fsck_online);
 	case BCH_IOCTL_QUERY_ACCOUNTING:
 		return bch2_ioctl_query_accounting(c, arg);
+	case BCH_IOCTL_QUERY_COUNTERS:
+		return bch2_ioctl_query_counters(c, arg);
 	default:
 		return -ENOTTY;
 	}
diff --git a/fs/bcachefs/checksum.c b/fs/bcachefs/checksum.c
index 23a383577d4c..3726689093e3 100644
--- a/fs/bcachefs/checksum.c
+++ b/fs/bcachefs/checksum.c
@@ -466,7 +466,7 @@ int bch2_rechecksum_bio(struct bch_fs *c, struct bio *bio,
 		prt_str(&buf, ")");
 		WARN_RATELIMIT(1, "%s", buf.buf);
 		printbuf_exit(&buf);
-		return -EIO;
+		return -BCH_ERR_recompute_checksum;
 	}
 
 	for (i = splits; i < splits + ARRAY_SIZE(splits); i++) {
@@ -693,6 +693,14 @@ static int bch2_alloc_ciphers(struct bch_fs *c)
 	return 0;
 }
 
+#if 0
+
+/*
+ * This seems to be duplicating code in cmd_remove_passphrase() in
+ * bcachefs-tools, but we might want to switch userspace to use this - and
+ * perhaps add an ioctl for calling this at runtime, so we can take the
+ * passphrase off of a mounted filesystem (which has come up).
+ */
 int bch2_disable_encryption(struct bch_fs *c)
 {
 	struct bch_sb_field_crypt *crypt;
@@ -725,6 +733,10 @@ int bch2_disable_encryption(struct bch_fs *c)
 	return ret;
 }
 
+/*
+ * For enabling encryption on an existing filesystem: not hooked up yet, but it
+ * should be
+ */
 int bch2_enable_encryption(struct bch_fs *c, bool keyed)
 {
 	struct bch_encrypted_key key;
@@ -781,6 +793,7 @@ int bch2_enable_encryption(struct bch_fs *c, bool keyed)
 	memzero_explicit(&key, sizeof(key));
 	return ret;
 }
+#endif
 
 void bch2_fs_encryption_exit(struct bch_fs *c)
 {
@@ -788,8 +801,6 @@ void bch2_fs_encryption_exit(struct bch_fs *c)
 		crypto_free_shash(c->poly1305);
 	if (c->chacha20)
 		crypto_free_sync_skcipher(c->chacha20);
-	if (c->sha256)
-		crypto_free_shash(c->sha256);
 }
 
 int bch2_fs_encryption_init(struct bch_fs *c)
@@ -798,14 +809,6 @@ int bch2_fs_encryption_init(struct bch_fs *c)
 	struct bch_key key;
 	int ret = 0;
 
-	c->sha256 = crypto_alloc_shash("sha256", 0, 0);
-	ret = PTR_ERR_OR_ZERO(c->sha256);
-	if (ret) {
-		c->sha256 = NULL;
-		bch_err(c, "error requesting sha256 module: %s", bch2_err_str(ret));
-		goto out;
-	}
-
 	crypt = bch2_sb_field_get(c->disk_sb.sb, crypt);
 	if (!crypt)
 		goto out;
diff --git a/fs/bcachefs/checksum.h b/fs/bcachefs/checksum.h
index 43b9d71f2f2b..4ac251c8fcd8 100644
--- a/fs/bcachefs/checksum.h
+++ b/fs/bcachefs/checksum.h
@@ -103,8 +103,10 @@ extern const struct bch_sb_field_ops bch_sb_field_ops_crypt;
 int bch2_decrypt_sb_key(struct bch_fs *, struct bch_sb_field_crypt *,
 			struct bch_key *);
 
+#if 0
 int bch2_disable_encryption(struct bch_fs *);
 int bch2_enable_encryption(struct bch_fs *, bool);
+#endif
 
 void bch2_fs_encryption_exit(struct bch_fs *);
 int bch2_fs_encryption_init(struct bch_fs *);
diff --git a/fs/bcachefs/compress.c b/fs/bcachefs/compress.c
index 114bf2f3879f..85fc90342492 100644
--- a/fs/bcachefs/compress.c
+++ b/fs/bcachefs/compress.c
@@ -177,7 +177,7 @@ static int __bio_uncompress(struct bch_fs *c, struct bio *src,
 	size_t src_len = src->bi_iter.bi_size;
 	size_t dst_len = crc.uncompressed_size << 9;
 	void *workspace;
-	int ret;
+	int ret = 0, ret2;
 
 	enum bch_compression_opts opt = bch2_compression_type_to_opt(crc.compression_type);
 	mempool_t *workspace_pool = &c->compress_workspace[opt];
@@ -189,7 +189,7 @@ static int __bio_uncompress(struct bch_fs *c, struct bio *src,
 		else
 			ret = -BCH_ERR_compression_workspace_not_initialized;
 		if (ret)
-			goto out;
+			goto err;
 	}
 
 	src_data = bio_map_or_bounce(c, src, READ);
@@ -197,10 +197,10 @@ static int __bio_uncompress(struct bch_fs *c, struct bio *src,
 	switch (crc.compression_type) {
 	case BCH_COMPRESSION_TYPE_lz4_old:
 	case BCH_COMPRESSION_TYPE_lz4:
-		ret = LZ4_decompress_safe_partial(src_data.b, dst_data,
-						  src_len, dst_len, dst_len);
-		if (ret != dst_len)
-			goto err;
+		ret2 = LZ4_decompress_safe_partial(src_data.b, dst_data,
+						   src_len, dst_len, dst_len);
+		if (ret2 != dst_len)
+			ret = -BCH_ERR_decompress_lz4;
 		break;
 	case BCH_COMPRESSION_TYPE_gzip: {
 		z_stream strm = {
@@ -214,45 +214,43 @@ static int __bio_uncompress(struct bch_fs *c, struct bio *src,
 
 		zlib_set_workspace(&strm, workspace);
 		zlib_inflateInit2(&strm, -MAX_WBITS);
-		ret = zlib_inflate(&strm, Z_FINISH);
+		ret2 = zlib_inflate(&strm, Z_FINISH);
 
 		mempool_free(workspace, workspace_pool);
 
-		if (ret != Z_STREAM_END)
-			goto err;
+		if (ret2 != Z_STREAM_END)
+			ret = -BCH_ERR_decompress_gzip;
 		break;
 	}
 	case BCH_COMPRESSION_TYPE_zstd: {
 		ZSTD_DCtx *ctx;
 		size_t real_src_len = le32_to_cpup(src_data.b);
 
-		if (real_src_len > src_len - 4)
+		if (real_src_len > src_len - 4) {
+			ret = -BCH_ERR_decompress_zstd_src_len_bad;
 			goto err;
+		}
 
 		workspace = mempool_alloc(workspace_pool, GFP_NOFS);
 		ctx = zstd_init_dctx(workspace, zstd_dctx_workspace_bound());
 
-		ret = zstd_decompress_dctx(ctx,
+		ret2 = zstd_decompress_dctx(ctx,
 				dst_data,	dst_len,
 				src_data.b + 4, real_src_len);
 
 		mempool_free(workspace, workspace_pool);
 
-		if (ret != dst_len)
-			goto err;
+		if (ret2 != dst_len)
+			ret = -BCH_ERR_decompress_zstd;
 		break;
 	}
 	default:
 		BUG();
 	}
-	ret = 0;
+err:
 fsck_err:
-out:
 	bio_unmap_or_unbounce(c, src_data);
 	return ret;
-err:
-	ret = -EIO;
-	goto out;
 }
 
 int bch2_bio_uncompress_inplace(struct bch_write_op *op,
@@ -268,27 +266,22 @@ int bch2_bio_uncompress_inplace(struct bch_write_op *op,
 	BUG_ON(!bio->bi_vcnt);
 	BUG_ON(DIV_ROUND_UP(crc->live_size, PAGE_SECTORS) > bio->bi_max_vecs);
 
-	if (crc->uncompressed_size << 9	> c->opts.encoded_extent_max ||
-	    crc->compressed_size << 9	> c->opts.encoded_extent_max) {
-		struct printbuf buf = PRINTBUF;
-		bch2_write_op_error(&buf, op);
-		prt_printf(&buf, "error rewriting existing data: extent too big");
-		bch_err_ratelimited(c, "%s", buf.buf);
-		printbuf_exit(&buf);
-		return -EIO;
+	if (crc->uncompressed_size << 9	> c->opts.encoded_extent_max) {
+		bch2_write_op_error(op, op->pos.offset,
+				    "extent too big to decompress (%u > %u)",
+				    crc->uncompressed_size << 9, c->opts.encoded_extent_max);
+		return -BCH_ERR_decompress_exceeded_max_encoded_extent;
 	}
 
 	data = __bounce_alloc(c, dst_len, WRITE);
 
-	if (__bio_uncompress(c, bio, data.b, *crc)) {
-		if (!c->opts.no_data_io) {
-			struct printbuf buf = PRINTBUF;
-			bch2_write_op_error(&buf, op);
-			prt_printf(&buf, "error rewriting existing data: decompression error");
-			bch_err_ratelimited(c, "%s", buf.buf);
-			printbuf_exit(&buf);
-		}
-		ret = -EIO;
+	ret = __bio_uncompress(c, bio, data.b, *crc);
+
+	if (c->opts.no_data_io)
+		ret = 0;
+
+	if (ret) {
+		bch2_write_op_error(op, op->pos.offset, "%s", bch2_err_str(ret));
 		goto err;
 	}
 
@@ -321,7 +314,7 @@ int bch2_bio_uncompress(struct bch_fs *c, struct bio *src,
 
 	if (crc.uncompressed_size << 9	> c->opts.encoded_extent_max ||
 	    crc.compressed_size << 9	> c->opts.encoded_extent_max)
-		return -EIO;
+		return -BCH_ERR_decompress_exceeded_max_encoded_extent;
 
 	dst_data = dst_len == dst_iter.bi_size
 		? __bio_map_or_bounce(c, dst, dst_iter, WRITE)
diff --git a/fs/bcachefs/data_update.c b/fs/bcachefs/data_update.c
index 642fbc60ecab..0ec273daccb7 100644
--- a/fs/bcachefs/data_update.c
+++ b/fs/bcachefs/data_update.c
@@ -20,6 +20,8 @@
 #include "subvolume.h"
 #include "trace.h"
 
+#include <linux/ioprio.h>
+
 static void bkey_put_dev_refs(struct bch_fs *c, struct bkey_s_c k)
 {
 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
@@ -33,7 +35,7 @@ static bool bkey_get_dev_refs(struct bch_fs *c, struct bkey_s_c k)
 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 
 	bkey_for_each_ptr(ptrs, ptr) {
-		if (!bch2_dev_tryget(c, ptr->dev)) {
+		if (unlikely(!bch2_dev_tryget(c, ptr->dev))) {
 			bkey_for_each_ptr(ptrs, ptr2) {
 				if (ptr2 == ptr)
 					break;
@@ -91,7 +93,7 @@ static bool bkey_nocow_lock(struct bch_fs *c, struct moving_context *ctxt, struc
 	return true;
 }
 
-static noinline void trace_move_extent_finish2(struct data_update *u,
+static noinline void trace_io_move_finish2(struct data_update *u,
 					       struct bkey_i *new,
 					       struct bkey_i *insert)
 {
@@ -111,11 +113,11 @@ static noinline void trace_move_extent_finish2(struct data_update *u,
 	bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(insert));
 	prt_newline(&buf);
 
-	trace_move_extent_finish(c, buf.buf);
+	trace_io_move_finish(c, buf.buf);
 	printbuf_exit(&buf);
 }
 
-static void trace_move_extent_fail2(struct data_update *m,
+static void trace_io_move_fail2(struct data_update *m,
 			 struct bkey_s_c new,
 			 struct bkey_s_c wrote,
 			 struct bkey_i *insert,
@@ -126,7 +128,7 @@ static void trace_move_extent_fail2(struct data_update *m,
 	struct printbuf buf = PRINTBUF;
 	unsigned rewrites_found = 0;
 
-	if (!trace_move_extent_fail_enabled())
+	if (!trace_io_move_fail_enabled())
 		return;
 
 	prt_str(&buf, msg);
@@ -166,7 +168,7 @@ static void trace_move_extent_fail2(struct data_update *m,
 		bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(insert));
 	}
 
-	trace_move_extent_fail(c, buf.buf);
+	trace_io_move_fail(c, buf.buf);
 	printbuf_exit(&buf);
 }
 
@@ -214,7 +216,7 @@ static int __bch2_data_update_index_update(struct btree_trans *trans,
 		new = bkey_i_to_extent(bch2_keylist_front(keys));
 
 		if (!bch2_extents_match(k, old)) {
-			trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i),
+			trace_io_move_fail2(m, k, bkey_i_to_s_c(&new->k_i),
 						NULL, "no match:");
 			goto nowork;
 		}
@@ -254,7 +256,7 @@ static int __bch2_data_update_index_update(struct btree_trans *trans,
 		if (m->data_opts.rewrite_ptrs &&
 		    !rewrites_found &&
 		    bch2_bkey_durability(c, k) >= m->op.opts.data_replicas) {
-			trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i), insert, "no rewrites found:");
+			trace_io_move_fail2(m, k, bkey_i_to_s_c(&new->k_i), insert, "no rewrites found:");
 			goto nowork;
 		}
 
@@ -271,7 +273,7 @@ static int __bch2_data_update_index_update(struct btree_trans *trans,
 			}
 
 		if (!bkey_val_u64s(&new->k)) {
-			trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i), insert, "new replicas conflicted:");
+			trace_io_move_fail2(m, k, bkey_i_to_s_c(&new->k_i), insert, "new replicas conflicted:");
 			goto nowork;
 		}
 
@@ -352,7 +354,7 @@ static int __bch2_data_update_index_update(struct btree_trans *trans,
 			printbuf_exit(&buf);
 
 			bch2_fatal_error(c);
-			ret = -EIO;
+			ret = -BCH_ERR_invalid_bkey;
 			goto out;
 		}
 
@@ -385,9 +387,9 @@ static int __bch2_data_update_index_update(struct btree_trans *trans,
 		if (!ret) {
 			bch2_btree_iter_set_pos(&iter, next_pos);
 
-			this_cpu_add(c->counters[BCH_COUNTER_move_extent_finish], new->k.size);
-			if (trace_move_extent_finish_enabled())
-				trace_move_extent_finish2(m, &new->k_i, insert);
+			this_cpu_add(c->counters[BCH_COUNTER_io_move_finish], new->k.size);
+			if (trace_io_move_finish_enabled())
+				trace_io_move_finish2(m, &new->k_i, insert);
 		}
 err:
 		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
@@ -409,7 +411,7 @@ static int __bch2_data_update_index_update(struct btree_trans *trans,
 				     &m->stats->sectors_raced);
 		}
 
-		count_event(c, move_extent_fail);
+		count_event(c, io_move_fail);
 
 		bch2_btree_iter_advance(&iter);
 		goto next;
@@ -427,14 +429,17 @@ int bch2_data_update_index_update(struct bch_write_op *op)
 	return bch2_trans_run(op->c, __bch2_data_update_index_update(trans, op));
 }
 
-void bch2_data_update_read_done(struct data_update *m,
-				struct bch_extent_crc_unpacked crc)
+void bch2_data_update_read_done(struct data_update *m)
 {
+	m->read_done = true;
+
 	/* write bio must own pages: */
 	BUG_ON(!m->op.wbio.bio.bi_vcnt);
 
-	m->op.crc = crc;
-	m->op.wbio.bio.bi_iter.bi_size = crc.compressed_size << 9;
+	m->op.crc = m->rbio.pick.crc;
+	m->op.wbio.bio.bi_iter.bi_size = m->op.crc.compressed_size << 9;
+
+	this_cpu_add(m->op.c->counters[BCH_COUNTER_io_move_write], m->k.k->k.size);
 
 	closure_call(&m->op.cl, bch2_write, NULL, NULL);
 }
@@ -444,31 +449,34 @@ void bch2_data_update_exit(struct data_update *update)
 	struct bch_fs *c = update->op.c;
 	struct bkey_s_c k = bkey_i_to_s_c(update->k.k);
 
+	bch2_bio_free_pages_pool(c, &update->op.wbio.bio);
+	kfree(update->bvecs);
+	update->bvecs = NULL;
+
 	if (c->opts.nocow_enabled)
 		bkey_nocow_unlock(c, k);
 	bkey_put_dev_refs(c, k);
-	bch2_bkey_buf_exit(&update->k, c);
 	bch2_disk_reservation_put(c, &update->op.res);
-	bch2_bio_free_pages_pool(c, &update->op.wbio.bio);
+	bch2_bkey_buf_exit(&update->k, c);
 }
 
-static void bch2_update_unwritten_extent(struct btree_trans *trans,
-				  struct data_update *update)
+static int bch2_update_unwritten_extent(struct btree_trans *trans,
+					struct data_update *update)
 {
 	struct bch_fs *c = update->op.c;
-	struct bio *bio = &update->op.wbio.bio;
 	struct bkey_i_extent *e;
 	struct write_point *wp;
 	struct closure cl;
 	struct btree_iter iter;
 	struct bkey_s_c k;
-	int ret;
+	int ret = 0;
 
 	closure_init_stack(&cl);
 	bch2_keylist_init(&update->op.insert_keys, update->op.inline_keys);
 
-	while (bio_sectors(bio)) {
-		unsigned sectors = bio_sectors(bio);
+	while (bpos_lt(update->op.pos, update->k.k->k.p)) {
+		unsigned sectors = update->k.k->k.p.offset -
+			update->op.pos.offset;
 
 		bch2_trans_begin(trans);
 
@@ -504,7 +512,7 @@ static void bch2_update_unwritten_extent(struct btree_trans *trans,
 		bch_err_fn_ratelimited(c, ret);
 
 		if (ret)
-			return;
+			break;
 
 		sectors = min(sectors, wp->sectors_free);
 
@@ -514,7 +522,6 @@ static void bch2_update_unwritten_extent(struct btree_trans *trans,
 		bch2_alloc_sectors_append_ptrs(c, wp, &e->k_i, sectors, false);
 		bch2_alloc_sectors_done(c, wp);
 
-		bio_advance(bio, sectors << 9);
 		update->op.pos.offset += sectors;
 
 		extent_for_each_ptr(extent_i_to_s(e), ptr)
@@ -533,13 +540,16 @@ static void bch2_update_unwritten_extent(struct btree_trans *trans,
 		bch2_trans_unlock(trans);
 		closure_sync(&cl);
 	}
+
+	return ret;
 }
 
 void bch2_data_update_opts_to_text(struct printbuf *out, struct bch_fs *c,
 				   struct bch_io_opts *io_opts,
 				   struct data_update_opts *data_opts)
 {
-	printbuf_tabstop_push(out, 20);
+	if (!out->nr_tabstops)
+		printbuf_tabstop_push(out, 20);
 
 	prt_str_indented(out, "rewrite ptrs:\t");
 	bch2_prt_u64_base2(out, data_opts->rewrite_ptrs);
@@ -574,6 +584,17 @@ void bch2_data_update_to_text(struct printbuf *out, struct data_update *m)
 	bch2_bkey_val_to_text(out, m->op.c, bkey_i_to_s_c(m->k.k));
 }
 
+void bch2_data_update_inflight_to_text(struct printbuf *out, struct data_update *m)
+{
+	bch2_bkey_val_to_text(out, m->op.c, bkey_i_to_s_c(m->k.k));
+	prt_newline(out);
+	printbuf_indent_add(out, 2);
+	bch2_data_update_opts_to_text(out, m->op.c, &m->op.opts, &m->data_opts);
+	prt_printf(out, "read_done:\t\%u\n", m->read_done);
+	bch2_write_op_to_text(out, &m->op);
+	printbuf_indent_sub(out, 2);
+}
+
 int bch2_extent_drop_ptrs(struct btree_trans *trans,
 			  struct btree_iter *iter,
 			  struct bkey_s_c k,
@@ -617,12 +638,85 @@ int bch2_extent_drop_ptrs(struct btree_trans *trans,
 		bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
 }
 
+int bch2_data_update_bios_init(struct data_update *m, struct bch_fs *c,
+			       struct bch_io_opts *io_opts)
+{
+	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(bkey_i_to_s_c(m->k.k));
+	const union bch_extent_entry *entry;
+	struct extent_ptr_decoded p;
+
+	/* write path might have to decompress data: */
+	unsigned buf_bytes = 0;
+	bkey_for_each_ptr_decode(&m->k.k->k, ptrs, p, entry)
+		buf_bytes = max_t(unsigned, buf_bytes, p.crc.uncompressed_size << 9);
+
+	unsigned nr_vecs = DIV_ROUND_UP(buf_bytes, PAGE_SIZE);
+
+	m->bvecs = kmalloc_array(nr_vecs, sizeof*(m->bvecs), GFP_KERNEL);
+	if (!m->bvecs)
+		return -ENOMEM;
+
+	bio_init(&m->rbio.bio,		NULL, m->bvecs, nr_vecs, REQ_OP_READ);
+	bio_init(&m->op.wbio.bio,	NULL, m->bvecs, nr_vecs, 0);
+
+	if (bch2_bio_alloc_pages(&m->op.wbio.bio, buf_bytes, GFP_KERNEL)) {
+		kfree(m->bvecs);
+		m->bvecs = NULL;
+		return -ENOMEM;
+	}
+
+	rbio_init(&m->rbio.bio, c, *io_opts, NULL);
+	m->rbio.data_update		= true;
+	m->rbio.bio.bi_iter.bi_size	= buf_bytes;
+	m->rbio.bio.bi_iter.bi_sector	= bkey_start_offset(&m->k.k->k);
+	m->op.wbio.bio.bi_ioprio	= IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0);
+	return 0;
+}
+
+static int can_write_extent(struct bch_fs *c, struct data_update *m)
+{
+	if ((m->op.flags & BCH_WRITE_alloc_nowait) &&
+	    unlikely(c->open_buckets_nr_free <= bch2_open_buckets_reserved(m->op.watermark)))
+		return -BCH_ERR_data_update_done_would_block;
+
+	unsigned target = m->op.flags & BCH_WRITE_only_specified_devs
+		? m->op.target
+		: 0;
+	struct bch_devs_mask devs = target_rw_devs(c, BCH_DATA_user, target);
+
+	darray_for_each(m->op.devs_have, i)
+		__clear_bit(*i, devs.d);
+
+	rcu_read_lock();
+	unsigned nr_replicas = 0, i;
+	for_each_set_bit(i, devs.d, BCH_SB_MEMBERS_MAX) {
+		struct bch_dev *ca = bch2_dev_rcu(c, i);
+
+		struct bch_dev_usage usage;
+		bch2_dev_usage_read_fast(ca, &usage);
+
+		if (!dev_buckets_free(ca, usage, m->op.watermark))
+			continue;
+
+		nr_replicas += ca->mi.durability;
+		if (nr_replicas >= m->op.nr_replicas)
+			break;
+	}
+	rcu_read_unlock();
+
+	if (!nr_replicas)
+		return -BCH_ERR_data_update_done_no_rw_devs;
+	if (nr_replicas < m->op.nr_replicas)
+		return -BCH_ERR_insufficient_devices;
+	return 0;
+}
+
 int bch2_data_update_init(struct btree_trans *trans,
 			  struct btree_iter *iter,
 			  struct moving_context *ctxt,
 			  struct data_update *m,
 			  struct write_point_specifier wp,
-			  struct bch_io_opts io_opts,
+			  struct bch_io_opts *io_opts,
 			  struct data_update_opts data_opts,
 			  enum btree_id btree_id,
 			  struct bkey_s_c k)
@@ -640,16 +734,7 @@ int bch2_data_update_init(struct btree_trans *trans,
 	 * snapshots table - just skip it, we can move it later.
 	 */
 	if (unlikely(k.k->p.snapshot && !bch2_snapshot_exists(c, k.k->p.snapshot)))
-		return -BCH_ERR_data_update_done;
-
-	if (!bkey_get_dev_refs(c, k))
-		return -BCH_ERR_data_update_done;
-
-	if (c->opts.nocow_enabled &&
-	    !bkey_nocow_lock(c, ctxt, k)) {
-		bkey_put_dev_refs(c, k);
-		return -BCH_ERR_nocow_lock_blocked;
-	}
+		return -BCH_ERR_data_update_done_no_snapshot;
 
 	bch2_bkey_buf_init(&m->k);
 	bch2_bkey_buf_reassemble(&m->k, c, k);
@@ -658,18 +743,18 @@ int bch2_data_update_init(struct btree_trans *trans,
 	m->ctxt		= ctxt;
 	m->stats	= ctxt ? ctxt->stats : NULL;
 
-	bch2_write_op_init(&m->op, c, io_opts);
+	bch2_write_op_init(&m->op, c, *io_opts);
 	m->op.pos	= bkey_start_pos(k.k);
 	m->op.version	= k.k->bversion;
 	m->op.target	= data_opts.target;
 	m->op.write_point = wp;
 	m->op.nr_replicas = 0;
-	m->op.flags	|= BCH_WRITE_PAGES_STABLE|
-		BCH_WRITE_PAGES_OWNED|
-		BCH_WRITE_DATA_ENCODED|
-		BCH_WRITE_MOVE|
+	m->op.flags	|= BCH_WRITE_pages_stable|
+		BCH_WRITE_pages_owned|
+		BCH_WRITE_data_encoded|
+		BCH_WRITE_move|
 		m->data_opts.write_flags;
-	m->op.compression_opt	= io_opts.background_compression;
+	m->op.compression_opt	= io_opts->background_compression;
 	m->op.watermark		= m->data_opts.btree_insert_flags & BCH_WATERMARK_MASK;
 
 	unsigned durability_have = 0, durability_removing = 0;
@@ -707,7 +792,7 @@ int bch2_data_update_init(struct btree_trans *trans,
 		ptr_bit <<= 1;
 	}
 
-	unsigned durability_required = max(0, (int) (io_opts.data_replicas - durability_have));
+	unsigned durability_required = max(0, (int) (io_opts->data_replicas - durability_have));
 
 	/*
 	 * If current extent durability is less than io_opts.data_replicas,
@@ -740,28 +825,70 @@ int bch2_data_update_init(struct btree_trans *trans,
 		m->data_opts.rewrite_ptrs = 0;
 		/* if iter == NULL, it's just a promote */
 		if (iter)
-			ret = bch2_extent_drop_ptrs(trans, iter, k, &io_opts, &m->data_opts);
-		goto out;
+			ret = bch2_extent_drop_ptrs(trans, iter, k, io_opts, &m->data_opts);
+		if (!ret)
+			ret = -BCH_ERR_data_update_done_no_writes_needed;
+		goto out_bkey_buf_exit;
 	}
 
+	/*
+	 * Check if the allocation will succeed, to avoid getting an error later
+	 * in bch2_write() -> bch2_alloc_sectors_start() and doing a useless
+	 * read:
+	 *
+	 * This guards against
+	 * - BCH_WRITE_alloc_nowait allocations failing (promotes)
+	 * - Destination target full
+	 * - Device(s) in destination target offline
+	 * - Insufficient durability available in destination target
+	 *   (i.e. trying to move a durability=2 replica to a target with a
+	 *   single durability=2 device)
+	 */
+	ret = can_write_extent(c, m);
+	if (ret)
+		goto out_bkey_buf_exit;
+
 	if (reserve_sectors) {
 		ret = bch2_disk_reservation_add(c, &m->op.res, reserve_sectors,
 				m->data_opts.extra_replicas
 				? 0
 				: BCH_DISK_RESERVATION_NOFAIL);
 		if (ret)
-			goto out;
+			goto out_bkey_buf_exit;
+	}
+
+	if (!bkey_get_dev_refs(c, k)) {
+		ret = -BCH_ERR_data_update_done_no_dev_refs;
+		goto out_put_disk_res;
+	}
+
+	if (c->opts.nocow_enabled &&
+	    !bkey_nocow_lock(c, ctxt, k)) {
+		ret = -BCH_ERR_nocow_lock_blocked;
+		goto out_put_dev_refs;
 	}
 
 	if (bkey_extent_is_unwritten(k)) {
-		bch2_update_unwritten_extent(trans, m);
-		goto out;
+		ret = bch2_update_unwritten_extent(trans, m) ?:
+			-BCH_ERR_data_update_done_unwritten;
+		goto out_nocow_unlock;
 	}
 
+	ret = bch2_data_update_bios_init(m, c, io_opts);
+	if (ret)
+		goto out_nocow_unlock;
+
 	return 0;
-out:
-	bch2_data_update_exit(m);
-	return ret ?: -BCH_ERR_data_update_done;
+out_nocow_unlock:
+	if (c->opts.nocow_enabled)
+		bkey_nocow_unlock(c, k);
+out_put_dev_refs:
+	bkey_put_dev_refs(c, k);
+out_put_disk_res:
+	bch2_disk_reservation_put(c, &m->op.res);
+out_bkey_buf_exit:
+	bch2_bkey_buf_exit(&m->k, c);
+	return ret;
 }
 
 void bch2_data_update_opts_normalize(struct bkey_s_c k, struct data_update_opts *opts)
diff --git a/fs/bcachefs/data_update.h b/fs/bcachefs/data_update.h
index e4b50723428e..c194cbbf5b51 100644
--- a/fs/bcachefs/data_update.h
+++ b/fs/bcachefs/data_update.h
@@ -4,6 +4,7 @@
 #define _BCACHEFS_DATA_UPDATE_H
 
 #include "bkey_buf.h"
+#include "io_read.h"
 #include "io_write_types.h"
 
 struct moving_context;
@@ -15,6 +16,9 @@ struct data_update_opts {
 	u8		extra_replicas;
 	unsigned	btree_insert_flags;
 	unsigned	write_flags;
+
+	int		read_dev;
+	bool		scrub;
 };
 
 void bch2_data_update_opts_to_text(struct printbuf *, struct bch_fs *,
@@ -22,20 +26,24 @@ void bch2_data_update_opts_to_text(struct printbuf *, struct bch_fs *,
 
 struct data_update {
 	/* extent being updated: */
+	bool			read_done;
 	enum btree_id		btree_id;
 	struct bkey_buf		k;
 	struct data_update_opts	data_opts;
 	struct moving_context	*ctxt;
 	struct bch_move_stats	*stats;
+
+	struct bch_read_bio	rbio;
 	struct bch_write_op	op;
+	struct bio_vec		*bvecs;
 };
 
 void bch2_data_update_to_text(struct printbuf *, struct data_update *);
+void bch2_data_update_inflight_to_text(struct printbuf *, struct data_update *);
 
 int bch2_data_update_index_update(struct bch_write_op *);
 
-void bch2_data_update_read_done(struct data_update *,
-				struct bch_extent_crc_unpacked);
+void bch2_data_update_read_done(struct data_update *);
 
 int bch2_extent_drop_ptrs(struct btree_trans *,
 			  struct btree_iter *,
@@ -43,12 +51,15 @@ int bch2_extent_drop_ptrs(struct btree_trans *,
 			  struct bch_io_opts *,
 			  struct data_update_opts *);
 
+int bch2_data_update_bios_init(struct data_update *, struct bch_fs *,
+			       struct bch_io_opts *);
+
 void bch2_data_update_exit(struct data_update *);
 int bch2_data_update_init(struct btree_trans *, struct btree_iter *,
 			  struct moving_context *,
 			  struct data_update *,
 			  struct write_point_specifier,
-			  struct bch_io_opts, struct data_update_opts,
+			  struct bch_io_opts *, struct data_update_opts,
 			  enum btree_id, struct bkey_s_c);
 void bch2_data_update_opts_normalize(struct bkey_s_c, struct data_update_opts *);
 
diff --git a/fs/bcachefs/debug.c b/fs/bcachefs/debug.c
index 55333e82d1fe..788af88f6979 100644
--- a/fs/bcachefs/debug.c
+++ b/fs/bcachefs/debug.c
@@ -7,6 +7,7 @@
  */
 
 #include "bcachefs.h"
+#include "alloc_foreground.h"
 #include "bkey_methods.h"
 #include "btree_cache.h"
 #include "btree_io.h"
@@ -190,7 +191,7 @@ void bch2_btree_node_ondisk_to_text(struct printbuf *out, struct bch_fs *c,
 	unsigned offset = 0;
 	int ret;
 
-	if (bch2_bkey_pick_read_device(c, bkey_i_to_s_c(&b->key), NULL, &pick) <= 0) {
+	if (bch2_bkey_pick_read_device(c, bkey_i_to_s_c(&b->key), NULL, &pick, -1) <= 0) {
 		prt_printf(out, "error getting device to read from: invalid device\n");
 		return;
 	}
@@ -844,8 +845,11 @@ static void btree_deadlock_to_text(struct printbuf *out, struct bch_fs *c)
 	seqmutex_unlock(&c->btree_trans_lock);
 }
 
-static ssize_t bch2_btree_deadlock_read(struct file *file, char __user *buf,
-					    size_t size, loff_t *ppos)
+typedef void (*fs_to_text_fn)(struct printbuf *, struct bch_fs *);
+
+static ssize_t bch2_simple_print(struct file *file, char __user *buf,
+				 size_t size, loff_t *ppos,
+				 fs_to_text_fn fn)
 {
 	struct dump_iter *i = file->private_data;
 	struct bch_fs *c = i->c;
@@ -856,7 +860,7 @@ static ssize_t bch2_btree_deadlock_read(struct file *file, char __user *buf,
 	i->ret	= 0;
 
 	if (!i->iter) {
-		btree_deadlock_to_text(&i->buf, c);
+		fn(&i->buf, c);
 		i->iter++;
 	}
 
@@ -869,6 +873,12 @@ static ssize_t bch2_btree_deadlock_read(struct file *file, char __user *buf,
 	return ret ?: i->ret;
 }
 
+static ssize_t bch2_btree_deadlock_read(struct file *file, char __user *buf,
+					size_t size, loff_t *ppos)
+{
+	return bch2_simple_print(file, buf, size, ppos, btree_deadlock_to_text);
+}
+
 static const struct file_operations btree_deadlock_ops = {
 	.owner		= THIS_MODULE,
 	.open		= bch2_dump_open,
@@ -876,6 +886,19 @@ static const struct file_operations btree_deadlock_ops = {
 	.read		= bch2_btree_deadlock_read,
 };
 
+static ssize_t bch2_write_points_read(struct file *file, char __user *buf,
+				     size_t size, loff_t *ppos)
+{
+	return bch2_simple_print(file, buf, size, ppos, bch2_write_points_to_text);
+}
+
+static const struct file_operations write_points_ops = {
+	.owner		= THIS_MODULE,
+	.open		= bch2_dump_open,
+	.release	= bch2_dump_release,
+	.read		= bch2_write_points_read,
+};
+
 void bch2_fs_debug_exit(struct bch_fs *c)
 {
 	if (!IS_ERR_OR_NULL(c->fs_debug_dir))
@@ -927,6 +950,9 @@ void bch2_fs_debug_init(struct bch_fs *c)
 	debugfs_create_file("btree_deadlock", 0400, c->fs_debug_dir,
 			    c->btree_debug, &btree_deadlock_ops);
 
+	debugfs_create_file("write_points", 0400, c->fs_debug_dir,
+			    c->btree_debug, &write_points_ops);
+
 	c->btree_debug_dir = debugfs_create_dir("btrees", c->fs_debug_dir);
 	if (IS_ERR_OR_NULL(c->btree_debug_dir))
 		return;
diff --git a/fs/bcachefs/dirent.c b/fs/bcachefs/dirent.c
index 600eee936f13..d7f9f79318a2 100644
--- a/fs/bcachefs/dirent.c
+++ b/fs/bcachefs/dirent.c
@@ -13,6 +13,40 @@
 
 #include <linux/dcache.h>
 
+static int bch2_casefold(struct btree_trans *trans, const struct bch_hash_info *info,
+				const struct qstr *str, struct qstr *out_cf)
+{
+	*out_cf = (struct qstr) QSTR_INIT(NULL, 0);
+
+#ifdef CONFIG_UNICODE
+	unsigned char *buf = bch2_trans_kmalloc(trans, BCH_NAME_MAX + 1);
+	int ret = PTR_ERR_OR_ZERO(buf);
+	if (ret)
+		return ret;
+
+	ret = utf8_casefold(info->cf_encoding, str, buf, BCH_NAME_MAX + 1);
+	if (ret <= 0)
+		return ret;
+
+	*out_cf = (struct qstr) QSTR_INIT(buf, ret);
+	return 0;
+#else
+	return -EOPNOTSUPP;
+#endif
+}
+
+static inline int bch2_maybe_casefold(struct btree_trans *trans,
+				      const struct bch_hash_info *info,
+				      const struct qstr *str, struct qstr *out_cf)
+{
+	if (likely(!info->cf_encoding)) {
+		*out_cf = *str;
+		return 0;
+	} else {
+		return bch2_casefold(trans, info, str, out_cf);
+	}
+}
+
 static unsigned bch2_dirent_name_bytes(struct bkey_s_c_dirent d)
 {
 	if (bkey_val_bytes(d.k) < offsetof(struct bch_dirent, d_name))
@@ -28,13 +62,38 @@ static unsigned bch2_dirent_name_bytes(struct bkey_s_c_dirent d)
 #endif
 
 	return bkey_bytes -
-		offsetof(struct bch_dirent, d_name) -
+		(d.v->d_casefold
+		? offsetof(struct bch_dirent, d_cf_name_block.d_names)
+		: offsetof(struct bch_dirent, d_name)) -
 		trailing_nuls;
 }
 
 struct qstr bch2_dirent_get_name(struct bkey_s_c_dirent d)
 {
-	return (struct qstr) QSTR_INIT(d.v->d_name, bch2_dirent_name_bytes(d));
+	if (d.v->d_casefold) {
+		unsigned name_len = le16_to_cpu(d.v->d_cf_name_block.d_name_len);
+		return (struct qstr) QSTR_INIT(&d.v->d_cf_name_block.d_names[0], name_len);
+	} else {
+		return (struct qstr) QSTR_INIT(d.v->d_name, bch2_dirent_name_bytes(d));
+	}
+}
+
+static struct qstr bch2_dirent_get_casefold_name(struct bkey_s_c_dirent d)
+{
+	if (d.v->d_casefold) {
+		unsigned name_len = le16_to_cpu(d.v->d_cf_name_block.d_name_len);
+		unsigned cf_name_len = le16_to_cpu(d.v->d_cf_name_block.d_cf_name_len);
+		return (struct qstr) QSTR_INIT(&d.v->d_cf_name_block.d_names[name_len], cf_name_len);
+	} else {
+		return (struct qstr) QSTR_INIT(NULL, 0);
+	}
+}
+
+static inline struct qstr bch2_dirent_get_lookup_name(struct bkey_s_c_dirent d)
+{
+	return d.v->d_casefold
+		? bch2_dirent_get_casefold_name(d)
+		: bch2_dirent_get_name(d);
 }
 
 static u64 bch2_dirent_hash(const struct bch_hash_info *info,
@@ -57,7 +116,7 @@ static u64 dirent_hash_key(const struct bch_hash_info *info, const void *key)
 static u64 dirent_hash_bkey(const struct bch_hash_info *info, struct bkey_s_c k)
 {
 	struct bkey_s_c_dirent d = bkey_s_c_to_dirent(k);
-	struct qstr name = bch2_dirent_get_name(d);
+	struct qstr name = bch2_dirent_get_lookup_name(d);
 
 	return bch2_dirent_hash(info, &name);
 }
@@ -65,7 +124,7 @@ static u64 dirent_hash_bkey(const struct bch_hash_info *info, struct bkey_s_c k)
 static bool dirent_cmp_key(struct bkey_s_c _l, const void *_r)
 {
 	struct bkey_s_c_dirent l = bkey_s_c_to_dirent(_l);
-	const struct qstr l_name = bch2_dirent_get_name(l);
+	const struct qstr l_name = bch2_dirent_get_lookup_name(l);
 	const struct qstr *r_name = _r;
 
 	return !qstr_eq(l_name, *r_name);
@@ -75,8 +134,8 @@ static bool dirent_cmp_bkey(struct bkey_s_c _l, struct bkey_s_c _r)
 {
 	struct bkey_s_c_dirent l = bkey_s_c_to_dirent(_l);
 	struct bkey_s_c_dirent r = bkey_s_c_to_dirent(_r);
-	const struct qstr l_name = bch2_dirent_get_name(l);
-	const struct qstr r_name = bch2_dirent_get_name(r);
+	const struct qstr l_name = bch2_dirent_get_lookup_name(l);
+	const struct qstr r_name = bch2_dirent_get_lookup_name(r);
 
 	return !qstr_eq(l_name, r_name);
 }
@@ -104,17 +163,19 @@ int bch2_dirent_validate(struct bch_fs *c, struct bkey_s_c k,
 			 struct bkey_validate_context from)
 {
 	struct bkey_s_c_dirent d = bkey_s_c_to_dirent(k);
+	unsigned name_block_len = bch2_dirent_name_bytes(d);
 	struct qstr d_name = bch2_dirent_get_name(d);
+	struct qstr d_cf_name = bch2_dirent_get_casefold_name(d);
 	int ret = 0;
 
 	bkey_fsck_err_on(!d_name.len,
 			 c, dirent_empty_name,
 			 "empty name");
 
-	bkey_fsck_err_on(bkey_val_u64s(k.k) > dirent_val_u64s(d_name.len),
+	bkey_fsck_err_on(d_name.len + d_cf_name.len > name_block_len,
 			 c, dirent_val_too_big,
-			 "value too big (%zu > %u)",
-			 bkey_val_u64s(k.k), dirent_val_u64s(d_name.len));
+			 "dirent names exceed bkey size (%d + %d > %d)",
+			 d_name.len, d_cf_name.len, name_block_len);
 
 	/*
 	 * Check new keys don't exceed the max length
@@ -142,6 +203,18 @@ int bch2_dirent_validate(struct bch_fs *c, struct bkey_s_c k,
 			 le64_to_cpu(d.v->d_inum) == d.k->p.inode,
 			 c, dirent_to_itself,
 			 "dirent points to own directory");
+
+	if (d.v->d_casefold) {
+		bkey_fsck_err_on(from.from == BKEY_VALIDATE_commit &&
+				 d_cf_name.len > BCH_NAME_MAX,
+				 c, dirent_cf_name_too_big,
+				 "dirent w/ cf name too big (%u > %u)",
+				 d_cf_name.len, BCH_NAME_MAX);
+
+		bkey_fsck_err_on(d_cf_name.len != strnlen(d_cf_name.name, d_cf_name.len),
+				 c, dirent_stray_data_after_cf_name,
+				 "dirent has stray data after cf name's NUL");
+	}
 fsck_err:
 	return ret;
 }
@@ -163,15 +236,14 @@ void bch2_dirent_to_text(struct printbuf *out, struct bch_fs *c, struct bkey_s_c
 	prt_printf(out, " type %s", bch2_d_type_str(d.v->d_type));
 }
 
-static struct bkey_i_dirent *dirent_create_key(struct btree_trans *trans,
-				subvol_inum dir, u8 type,
-				const struct qstr *name, u64 dst)
+static struct bkey_i_dirent *dirent_alloc_key(struct btree_trans *trans,
+				subvol_inum dir,
+				u8 type,
+				int name_len, int cf_name_len,
+				u64 dst)
 {
 	struct bkey_i_dirent *dirent;
-	unsigned u64s = BKEY_U64s + dirent_val_u64s(name->len);
-
-	if (name->len > BCH_NAME_MAX)
-		return ERR_PTR(-ENAMETOOLONG);
+	unsigned u64s = BKEY_U64s + dirent_val_u64s(name_len, cf_name_len);
 
 	BUG_ON(u64s > U8_MAX);
 
@@ -190,14 +262,65 @@ static struct bkey_i_dirent *dirent_create_key(struct btree_trans *trans,
 	}
 
 	dirent->v.d_type = type;
+	dirent->v.d_unused = 0;
+	dirent->v.d_casefold = cf_name_len ? 1 : 0;
 
-	memcpy(dirent->v.d_name, name->name, name->len);
-	memset(dirent->v.d_name + name->len, 0,
-	       bkey_val_bytes(&dirent->k) -
-	       offsetof(struct bch_dirent, d_name) -
-	       name->len);
+	return dirent;
+}
 
-	EBUG_ON(bch2_dirent_name_bytes(dirent_i_to_s_c(dirent)) != name->len);
+static void dirent_init_regular_name(struct bkey_i_dirent *dirent,
+				     const struct qstr *name)
+{
+	EBUG_ON(dirent->v.d_casefold);
+
+	memcpy(&dirent->v.d_name[0], name->name, name->len);
+	memset(&dirent->v.d_name[name->len], 0,
+		bkey_val_bytes(&dirent->k) -
+		offsetof(struct bch_dirent, d_name) -
+		name->len);
+}
+
+static void dirent_init_casefolded_name(struct bkey_i_dirent *dirent,
+					const struct qstr *name,
+					const struct qstr *cf_name)
+{
+	EBUG_ON(!dirent->v.d_casefold);
+	EBUG_ON(!cf_name->len);
+
+	dirent->v.d_cf_name_block.d_name_len = name->len;
+	dirent->v.d_cf_name_block.d_cf_name_len = cf_name->len;
+	memcpy(&dirent->v.d_cf_name_block.d_names[0], name->name, name->len);
+	memcpy(&dirent->v.d_cf_name_block.d_names[name->len], cf_name->name, cf_name->len);
+	memset(&dirent->v.d_cf_name_block.d_names[name->len + cf_name->len], 0,
+		bkey_val_bytes(&dirent->k) -
+		offsetof(struct bch_dirent, d_cf_name_block.d_names) -
+		name->len + cf_name->len);
+
+	EBUG_ON(bch2_dirent_get_casefold_name(dirent_i_to_s_c(dirent)).len != cf_name->len);
+}
+
+static struct bkey_i_dirent *dirent_create_key(struct btree_trans *trans,
+				subvol_inum dir,
+				u8 type,
+				const struct qstr *name,
+				const struct qstr *cf_name,
+				u64 dst)
+{
+	struct bkey_i_dirent *dirent;
+
+	if (name->len > BCH_NAME_MAX)
+		return ERR_PTR(-ENAMETOOLONG);
+
+	dirent = dirent_alloc_key(trans, dir, type, name->len, cf_name ? cf_name->len : 0, dst);
+	if (IS_ERR(dirent))
+		return dirent;
+
+	if (cf_name)
+		dirent_init_casefolded_name(dirent, name, cf_name);
+	else
+		dirent_init_regular_name(dirent, name);
+
+	EBUG_ON(bch2_dirent_get_name(dirent_i_to_s_c(dirent)).len != name->len);
 
 	return dirent;
 }
@@ -213,7 +336,7 @@ int bch2_dirent_create_snapshot(struct btree_trans *trans,
 	struct bkey_i_dirent *dirent;
 	int ret;
 
-	dirent = dirent_create_key(trans, dir_inum, type, name, dst_inum);
+	dirent = dirent_create_key(trans, dir_inum, type, name, NULL, dst_inum);
 	ret = PTR_ERR_OR_ZERO(dirent);
 	if (ret)
 		return ret;
@@ -233,16 +356,28 @@ int bch2_dirent_create(struct btree_trans *trans, subvol_inum dir,
 		       const struct bch_hash_info *hash_info,
 		       u8 type, const struct qstr *name, u64 dst_inum,
 		       u64 *dir_offset,
+		       u64 *i_size,
 		       enum btree_iter_update_trigger_flags flags)
 {
 	struct bkey_i_dirent *dirent;
 	int ret;
 
-	dirent = dirent_create_key(trans, dir, type, name, dst_inum);
+	if (hash_info->cf_encoding) {
+		struct qstr cf_name;
+		ret = bch2_casefold(trans, hash_info, name, &cf_name);
+		if (ret)
+			return ret;
+		dirent = dirent_create_key(trans, dir, type, name, &cf_name, dst_inum);
+	} else {
+		dirent = dirent_create_key(trans, dir, type, name, NULL, dst_inum);
+	}
+
 	ret = PTR_ERR_OR_ZERO(dirent);
 	if (ret)
 		return ret;
 
+	*i_size += bkey_bytes(&dirent->k);
+
 	ret = bch2_hash_set(trans, bch2_dirent_hash_desc, hash_info,
 			    dir, &dirent->k_i, flags);
 	*dir_offset = dirent->k.p.offset;
@@ -275,12 +410,13 @@ int bch2_dirent_read_target(struct btree_trans *trans, subvol_inum dir,
 }
 
 int bch2_dirent_rename(struct btree_trans *trans,
-		subvol_inum src_dir, struct bch_hash_info *src_hash,
-		subvol_inum dst_dir, struct bch_hash_info *dst_hash,
+		subvol_inum src_dir, struct bch_hash_info *src_hash, u64 *src_dir_i_size,
+		subvol_inum dst_dir, struct bch_hash_info *dst_hash, u64 *dst_dir_i_size,
 		const struct qstr *src_name, subvol_inum *src_inum, u64 *src_offset,
 		const struct qstr *dst_name, subvol_inum *dst_inum, u64 *dst_offset,
 		enum bch_rename_mode mode)
 {
+	struct qstr src_name_lookup, dst_name_lookup;
 	struct btree_iter src_iter = { NULL };
 	struct btree_iter dst_iter = { NULL };
 	struct bkey_s_c old_src, old_dst = bkey_s_c_null;
@@ -295,8 +431,11 @@ int bch2_dirent_rename(struct btree_trans *trans,
 	memset(dst_inum, 0, sizeof(*dst_inum));
 
 	/* Lookup src: */
+	ret = bch2_maybe_casefold(trans, src_hash, src_name, &src_name_lookup);
+	if (ret)
+		goto out;
 	old_src = bch2_hash_lookup(trans, &src_iter, bch2_dirent_hash_desc,
-				   src_hash, src_dir, src_name,
+				   src_hash, src_dir, &src_name_lookup,
 				   BTREE_ITER_intent);
 	ret = bkey_err(old_src);
 	if (ret)
@@ -308,6 +447,9 @@ int bch2_dirent_rename(struct btree_trans *trans,
 		goto out;
 
 	/* Lookup dst: */
+	ret = bch2_maybe_casefold(trans, dst_hash, dst_name, &dst_name_lookup);
+	if (ret)
+		goto out;
 	if (mode == BCH_RENAME) {
 		/*
 		 * Note that we're _not_ checking if the target already exists -
@@ -315,12 +457,12 @@ int bch2_dirent_rename(struct btree_trans *trans,
 		 * correctness:
 		 */
 		ret = bch2_hash_hole(trans, &dst_iter, bch2_dirent_hash_desc,
-				     dst_hash, dst_dir, dst_name);
+				     dst_hash, dst_dir, &dst_name_lookup);
 		if (ret)
 			goto out;
 	} else {
 		old_dst = bch2_hash_lookup(trans, &dst_iter, bch2_dirent_hash_desc,
-					    dst_hash, dst_dir, dst_name,
+					    dst_hash, dst_dir, &dst_name_lookup,
 					    BTREE_ITER_intent);
 		ret = bkey_err(old_dst);
 		if (ret)
@@ -336,7 +478,8 @@ int bch2_dirent_rename(struct btree_trans *trans,
 		*src_offset = dst_iter.pos.offset;
 
 	/* Create new dst key: */
-	new_dst = dirent_create_key(trans, dst_dir, 0, dst_name, 0);
+	new_dst = dirent_create_key(trans, dst_dir, 0, dst_name,
+				    dst_hash->cf_encoding ? &dst_name_lookup : NULL, 0);
 	ret = PTR_ERR_OR_ZERO(new_dst);
 	if (ret)
 		goto out;
@@ -346,7 +489,8 @@ int bch2_dirent_rename(struct btree_trans *trans,
 
 	/* Create new src key: */
 	if (mode == BCH_RENAME_EXCHANGE) {
-		new_src = dirent_create_key(trans, src_dir, 0, src_name, 0);
+		new_src = dirent_create_key(trans, src_dir, 0, src_name,
+					    src_hash->cf_encoding ? &src_name_lookup : NULL, 0);
 		ret = PTR_ERR_OR_ZERO(new_src);
 		if (ret)
 			goto out;
@@ -406,6 +550,14 @@ int bch2_dirent_rename(struct btree_trans *trans,
 	    new_src->v.d_type == DT_SUBVOL)
 		new_src->v.d_parent_subvol = cpu_to_le32(src_dir.subvol);
 
+	if (old_dst.k)
+		*dst_dir_i_size -= bkey_bytes(old_dst.k);
+	*src_dir_i_size -= bkey_bytes(old_src.k);
+
+	if (mode == BCH_RENAME_EXCHANGE)
+		*src_dir_i_size += bkey_bytes(&new_src->k);
+	*dst_dir_i_size += bkey_bytes(&new_dst->k);
+
 	ret = bch2_trans_update(trans, &dst_iter, &new_dst->k_i, 0);
 	if (ret)
 		goto out;
@@ -465,9 +617,14 @@ int bch2_dirent_lookup_trans(struct btree_trans *trans,
 			     const struct qstr *name, subvol_inum *inum,
 			     unsigned flags)
 {
+	struct qstr lookup_name;
+	int ret = bch2_maybe_casefold(trans, hash_info, name, &lookup_name);
+	if (ret)
+		return ret;
+
 	struct bkey_s_c k = bch2_hash_lookup(trans, iter, bch2_dirent_hash_desc,
-					     hash_info, dir, name, flags);
-	int ret = bkey_err(k);
+					     hash_info, dir, &lookup_name, flags);
+	ret = bkey_err(k);
 	if (ret)
 		goto err;
 
@@ -572,3 +729,54 @@ int bch2_readdir(struct bch_fs *c, subvol_inum inum, struct dir_context *ctx)
 
 	return ret < 0 ? ret : 0;
 }
+
+/* fsck */
+
+static int lookup_first_inode(struct btree_trans *trans, u64 inode_nr,
+			      struct bch_inode_unpacked *inode)
+{
+	struct btree_iter iter;
+	struct bkey_s_c k;
+	int ret;
+
+	for_each_btree_key_norestart(trans, iter, BTREE_ID_inodes, POS(0, inode_nr),
+				     BTREE_ITER_all_snapshots, k, ret) {
+		if (k.k->p.offset != inode_nr)
+			break;
+		if (!bkey_is_inode(k.k))
+			continue;
+		ret = bch2_inode_unpack(k, inode);
+		goto found;
+	}
+	ret = -BCH_ERR_ENOENT_inode;
+found:
+	bch_err_msg(trans->c, ret, "fetching inode %llu", inode_nr);
+	bch2_trans_iter_exit(trans, &iter);
+	return ret;
+}
+
+int bch2_fsck_remove_dirent(struct btree_trans *trans, struct bpos pos)
+{
+	struct bch_fs *c = trans->c;
+	struct btree_iter iter;
+	struct bch_inode_unpacked dir_inode;
+	struct bch_hash_info dir_hash_info;
+	int ret;
+
+	ret = lookup_first_inode(trans, pos.inode, &dir_inode);
+	if (ret)
+		goto err;
+
+	dir_hash_info = bch2_hash_info_init(c, &dir_inode);
+
+	bch2_trans_iter_init(trans, &iter, BTREE_ID_dirents, pos, BTREE_ITER_intent);
+
+	ret =   bch2_btree_iter_traverse(&iter) ?:
+		bch2_hash_delete_at(trans, bch2_dirent_hash_desc,
+				    &dir_hash_info, &iter,
+				    BTREE_UPDATE_internal_snapshot_node);
+	bch2_trans_iter_exit(trans, &iter);
+err:
+	bch_err_fn(c, ret);
+	return ret;
+}
diff --git a/fs/bcachefs/dirent.h b/fs/bcachefs/dirent.h
index 362b3b2f2f2e..0880772b80a9 100644
--- a/fs/bcachefs/dirent.h
+++ b/fs/bcachefs/dirent.h
@@ -25,10 +25,13 @@ struct bch_inode_info;
 
 struct qstr bch2_dirent_get_name(struct bkey_s_c_dirent d);
 
-static inline unsigned dirent_val_u64s(unsigned len)
+static inline unsigned dirent_val_u64s(unsigned len, unsigned cf_len)
 {
-	return DIV_ROUND_UP(offsetof(struct bch_dirent, d_name) + len,
-			    sizeof(u64));
+	unsigned bytes = cf_len
+		? offsetof(struct bch_dirent, d_cf_name_block.d_names) + len + cf_len
+		: offsetof(struct bch_dirent, d_name) + len;
+
+	return DIV_ROUND_UP(bytes, sizeof(u64));
 }
 
 int bch2_dirent_read_target(struct btree_trans *, subvol_inum,
@@ -47,7 +50,7 @@ int bch2_dirent_create_snapshot(struct btree_trans *, u32, u64, u32,
 			enum btree_iter_update_trigger_flags);
 int bch2_dirent_create(struct btree_trans *, subvol_inum,
 		       const struct bch_hash_info *, u8,
-		       const struct qstr *, u64, u64 *,
+		       const struct qstr *, u64, u64 *, u64 *,
 		       enum btree_iter_update_trigger_flags);
 
 static inline unsigned vfs_d_type(unsigned type)
@@ -62,8 +65,8 @@ enum bch_rename_mode {
 };
 
 int bch2_dirent_rename(struct btree_trans *,
-		       subvol_inum, struct bch_hash_info *,
-		       subvol_inum, struct bch_hash_info *,
+		       subvol_inum, struct bch_hash_info *, u64 *,
+		       subvol_inum, struct bch_hash_info *, u64 *,
 		       const struct qstr *, subvol_inum *, u64 *,
 		       const struct qstr *, subvol_inum *, u64 *,
 		       enum bch_rename_mode);
@@ -79,4 +82,6 @@ int bch2_empty_dir_snapshot(struct btree_trans *, u64, u32, u32);
 int bch2_empty_dir_trans(struct btree_trans *, subvol_inum);
 int bch2_readdir(struct bch_fs *, subvol_inum, struct dir_context *);
 
+int bch2_fsck_remove_dirent(struct btree_trans *, struct bpos);
+
 #endif /* _BCACHEFS_DIRENT_H */
diff --git a/fs/bcachefs/dirent_format.h b/fs/bcachefs/dirent_format.h
index 5e116b88e814..a46dbddd21aa 100644
--- a/fs/bcachefs/dirent_format.h
+++ b/fs/bcachefs/dirent_format.h
@@ -29,9 +29,25 @@ struct bch_dirent {
 	 * Copy of mode bits 12-15 from the target inode - so userspace can get
 	 * the filetype without having to do a stat()
 	 */
-	__u8			d_type;
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+	__u8			d_type:5,
+				d_unused:2,
+				d_casefold:1;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+	__u8			d_casefold:1,
+				d_unused:2,
+				d_type:5;
+#endif
 
-	__u8			d_name[];
+	union {
+	struct {
+		__u8		d_pad;
+		__le16		d_name_len;
+		__le16		d_cf_name_len;
+		__u8		d_names[];
+	} d_cf_name_block __packed;
+	__DECLARE_FLEX_ARRAY(__u8, d_name);
+	} __packed;
 } __packed __aligned(8);
 
 #define DT_SUBVOL	16
diff --git a/fs/bcachefs/disk_accounting.c b/fs/bcachefs/disk_accounting.c
index b32e91ba8be8..8a8de61429d8 100644
--- a/fs/bcachefs/disk_accounting.c
+++ b/fs/bcachefs/disk_accounting.c
@@ -135,6 +135,12 @@ static inline bool is_zero(char *start, char *end)
 
 #define field_end(p, member)	(((void *) (&p.member)) + sizeof(p.member))
 
+static const unsigned bch2_accounting_type_nr_counters[] = {
+#define x(f, id, nr)	[BCH_DISK_ACCOUNTING_##f]	= nr,
+	BCH_DISK_ACCOUNTING_TYPES()
+#undef x
+};
+
 int bch2_accounting_validate(struct bch_fs *c, struct bkey_s_c k,
 			     struct bkey_validate_context from)
 {
@@ -193,6 +199,11 @@ int bch2_accounting_validate(struct bch_fs *c, struct bkey_s_c k,
 	bkey_fsck_err_on(!is_zero(end, (void *) (&acc_k + 1)),
 			 c, accounting_key_junk_at_end,
 			 "junk at end of accounting key");
+
+	bkey_fsck_err_on(bch2_accounting_counters(k.k) != bch2_accounting_type_nr_counters[acc_k.type],
+			 c, accounting_key_nr_counters_wrong,
+			 "accounting key with %u counters, should be %u",
+			 bch2_accounting_counters(k.k), bch2_accounting_type_nr_counters[acc_k.type]);
 fsck_err:
 	return ret;
 }
diff --git a/fs/bcachefs/disk_accounting.h b/fs/bcachefs/disk_accounting.h
index f4372cafea2e..abb1f6206fe9 100644
--- a/fs/bcachefs/disk_accounting.h
+++ b/fs/bcachefs/disk_accounting.h
@@ -33,10 +33,12 @@ static inline bool bch2_accounting_key_is_zero(struct bkey_s_c_accounting a)
 static inline void bch2_accounting_accumulate(struct bkey_i_accounting *dst,
 					      struct bkey_s_c_accounting src)
 {
-	EBUG_ON(dst->k.u64s != src.k->u64s);
-
-	for (unsigned i = 0; i < bch2_accounting_counters(&dst->k); i++)
+	for (unsigned i = 0;
+	     i < min(bch2_accounting_counters(&dst->k),
+		     bch2_accounting_counters(src.k));
+	     i++)
 		dst->v.d[i] += src.v->d[i];
+
 	if (bversion_cmp(dst->k.bversion, src.k->bversion) < 0)
 		dst->k.bversion = src.k->bversion;
 }
@@ -85,6 +87,24 @@ static inline struct bpos disk_accounting_pos_to_bpos(struct disk_accounting_pos
 
 int bch2_disk_accounting_mod(struct btree_trans *, struct disk_accounting_pos *,
 			     s64 *, unsigned, bool);
+
+#define disk_accounting_key_init(_k, _type, ...)			\
+do {									\
+	memset(&(_k), 0, sizeof(_k));					\
+	(_k).type	= BCH_DISK_ACCOUNTING_##_type;			\
+	(_k)._type	= (struct bch_acct_##_type) { __VA_ARGS__ };	\
+} while (0)
+
+#define bch2_disk_accounting_mod2_nr(_trans, _gc, _v, _nr, ...)		\
+({									\
+	struct disk_accounting_pos pos;					\
+	disk_accounting_key_init(pos, __VA_ARGS__);			\
+	bch2_disk_accounting_mod(trans, &pos, _v, _nr, _gc);		\
+})
+
+#define bch2_disk_accounting_mod2(_trans, _gc, _v, ...)			\
+	bch2_disk_accounting_mod2_nr(_trans, _gc, _v, ARRAY_SIZE(_v), __VA_ARGS__)
+
 int bch2_mod_dev_cached_sectors(struct btree_trans *, unsigned, s64, bool);
 
 int bch2_accounting_validate(struct bch_fs *, struct bkey_s_c,
diff --git a/fs/bcachefs/disk_accounting_format.h b/fs/bcachefs/disk_accounting_format.h
index 7b6e6c97e6aa..8269af1dbe2a 100644
--- a/fs/bcachefs/disk_accounting_format.h
+++ b/fs/bcachefs/disk_accounting_format.h
@@ -95,40 +95,81 @@ static inline bool data_type_is_hidden(enum bch_data_type type)
 	}
 }
 
+/*
+ * field 1: name
+ * field 2: id
+ * field 3: number of counters (max 3)
+ */
+
 #define BCH_DISK_ACCOUNTING_TYPES()		\
-	x(nr_inodes,		0)		\
-	x(persistent_reserved,	1)		\
-	x(replicas,		2)		\
-	x(dev_data_type,	3)		\
-	x(compression,		4)		\
-	x(snapshot,		5)		\
-	x(btree,		6)		\
-	x(rebalance_work,	7)		\
-	x(inum,			8)
+	x(nr_inodes,		0,	1)	\
+	x(persistent_reserved,	1,	1)	\
+	x(replicas,		2,	1)	\
+	x(dev_data_type,	3,	3)	\
+	x(compression,		4,	3)	\
+	x(snapshot,		5,	1)	\
+	x(btree,		6,	1)	\
+	x(rebalance_work,	7,	1)	\
+	x(inum,			8,	3)
 
 enum disk_accounting_type {
-#define x(f, nr)	BCH_DISK_ACCOUNTING_##f	= nr,
+#define x(f, nr, ...)	BCH_DISK_ACCOUNTING_##f	= nr,
 	BCH_DISK_ACCOUNTING_TYPES()
 #undef x
 	BCH_DISK_ACCOUNTING_TYPE_NR,
 };
 
-struct bch_nr_inodes {
+/*
+ * No subtypes - number of inodes in the entire filesystem
+ *
+ * XXX: perhaps we could add a per-subvolume counter?
+ */
+struct bch_acct_nr_inodes {
 };
 
-struct bch_persistent_reserved {
+/*
+ * Tracks KEY_TYPE_reservation sectors, broken out by number of replicas for the
+ * reservation:
+ */
+struct bch_acct_persistent_reserved {
 	__u8			nr_replicas;
 };
 
-struct bch_dev_data_type {
+/*
+ * device, data type counter fields:
+ * [
+ *   nr_buckets
+ *   live sectors (in buckets of that data type)
+ *   sectors of internal fragmentation
+ * ]
+ *
+ * XXX: live sectors should've been done differently, you can have multiple data
+ * types in the same bucket (user, stripe, cached) and this collapses them to
+ * the bucket data type, and makes the internal fragmentation counter redundant
+ */
+struct bch_acct_dev_data_type {
 	__u8			dev;
 	__u8			data_type;
 };
 
+/*
+ * Compression type fields:
+ * [
+ *   number of extents
+ *   uncompressed size
+ *   compressed size
+ * ]
+ *
+ * Compression ratio, average extent size (fragmentation).
+ */
 struct bch_acct_compression {
 	__u8			type;
 };
 
+/*
+ * On disk usage by snapshot id; counts same values as replicas counter, but
+ * aggregated differently
+ */
 struct bch_acct_snapshot {
 	__u32			id;
 } __packed;
@@ -137,10 +178,27 @@ struct bch_acct_btree {
 	__u32			id;
 } __packed;
 
+/*
+ * inum counter fields:
+ * [
+ *   number of extents
+ *   sum of extent sizes - bkey size
+ *     this field is similar to inode.bi_sectors, except here extents in
+ *     different snapshots but the same inode number are all collapsed to the
+ *     same counter
+ *   sum of on disk size - same values tracked by replicas counters
+ * ]
+ *
+ * This tracks on disk fragmentation.
+ */
 struct bch_acct_inum {
 	__u64			inum;
 } __packed;
 
+/*
+ * Simple counter of the amount of data (on disk sectors) rebalance needs to
+ * move, extents counted here are also in the rebalance_work btree.
+ */
 struct bch_acct_rebalance_work {
 };
 
@@ -149,10 +207,10 @@ struct disk_accounting_pos {
 	struct {
 		__u8				type;
 		union {
-		struct bch_nr_inodes		nr_inodes;
-		struct bch_persistent_reserved	persistent_reserved;
+		struct bch_acct_nr_inodes	nr_inodes;
+		struct bch_acct_persistent_reserved	persistent_reserved;
 		struct bch_replicas_entry_v1	replicas;
-		struct bch_dev_data_type	dev_data_type;
+		struct bch_acct_dev_data_type	dev_data_type;
 		struct bch_acct_compression	compression;
 		struct bch_acct_snapshot	snapshot;
 		struct bch_acct_btree		btree;
diff --git a/fs/bcachefs/ec.c b/fs/bcachefs/ec.c
index d2a5e76e6479..f2b9225fe0bc 100644
--- a/fs/bcachefs/ec.c
+++ b/fs/bcachefs/ec.c
@@ -20,6 +20,7 @@
 #include "io_read.h"
 #include "io_write.h"
 #include "keylist.h"
+#include "lru.h"
 #include "recovery.h"
 #include "replicas.h"
 #include "super-io.h"
@@ -104,6 +105,7 @@ struct ec_bio {
 	struct bch_dev		*ca;
 	struct ec_stripe_buf	*buf;
 	size_t			idx;
+	u64			submit_time;
 	struct bio		bio;
 };
 
@@ -298,10 +300,22 @@ static int mark_stripe_bucket(struct btree_trans *trans,
 	struct bpos bucket = PTR_BUCKET_POS(ca, ptr);
 
 	if (flags & BTREE_TRIGGER_transactional) {
+		struct extent_ptr_decoded p = {
+			.ptr = *ptr,
+			.crc = bch2_extent_crc_unpack(s.k, NULL),
+		};
+		struct bkey_i_backpointer bp;
+		bch2_extent_ptr_to_bp(c, BTREE_ID_stripes, 0, s.s_c, p,
+				      (const union bch_extent_entry *) ptr, &bp);
+
 		struct bkey_i_alloc_v4 *a =
 			bch2_trans_start_alloc_update(trans, bucket, 0);
-		ret = PTR_ERR_OR_ZERO(a) ?:
-			__mark_stripe_bucket(trans, ca, s, ptr_idx, deleting, bucket, &a->v, flags);
+		ret   = PTR_ERR_OR_ZERO(a) ?:
+			__mark_stripe_bucket(trans, ca, s, ptr_idx, deleting, bucket, &a->v, flags) ?:
+			bch2_bucket_backpointer_mod(trans, s.s_c, &bp,
+						    !(flags & BTREE_TRIGGER_overwrite));
+		if (ret)
+			goto err;
 	}
 
 	if (flags & BTREE_TRIGGER_gc) {
@@ -366,19 +380,6 @@ static int mark_stripe_buckets(struct btree_trans *trans,
 	return 0;
 }
 
-static inline void stripe_to_mem(struct stripe *m, const struct bch_stripe *s)
-{
-	m->sectors	= le16_to_cpu(s->sectors);
-	m->algorithm	= s->algorithm;
-	m->nr_blocks	= s->nr_blocks;
-	m->nr_redundant	= s->nr_redundant;
-	m->disk_label	= s->disk_label;
-	m->blocks_nonempty = 0;
-
-	for (unsigned i = 0; i < s->nr_blocks; i++)
-		m->blocks_nonempty += !!stripe_blockcount_get(s, i);
-}
-
 int bch2_trigger_stripe(struct btree_trans *trans,
 			enum btree_id btree, unsigned level,
 			struct bkey_s_c old, struct bkey_s _new,
@@ -399,6 +400,15 @@ int bch2_trigger_stripe(struct btree_trans *trans,
 	       (new_s->nr_blocks	!= old_s->nr_blocks ||
 		new_s->nr_redundant	!= old_s->nr_redundant));
 
+	if (flags & BTREE_TRIGGER_transactional) {
+		int ret = bch2_lru_change(trans,
+					  BCH_LRU_STRIPE_FRAGMENTATION,
+					  idx,
+					  stripe_lru_pos(old_s),
+					  stripe_lru_pos(new_s));
+		if (ret)
+			return ret;
+	}
 
 	if (flags & (BTREE_TRIGGER_transactional|BTREE_TRIGGER_gc)) {
 		/*
@@ -472,38 +482,6 @@ int bch2_trigger_stripe(struct btree_trans *trans,
 			return ret;
 	}
 
-	if (flags & BTREE_TRIGGER_atomic) {
-		struct stripe *m = genradix_ptr(&c->stripes, idx);
-
-		if (!m) {
-			struct printbuf buf1 = PRINTBUF;
-			struct printbuf buf2 = PRINTBUF;
-
-			bch2_bkey_val_to_text(&buf1, c, old);
-			bch2_bkey_val_to_text(&buf2, c, new);
-			bch_err_ratelimited(c, "error marking nonexistent stripe %llu while marking\n"
-					    "old %s\n"
-					    "new %s", idx, buf1.buf, buf2.buf);
-			printbuf_exit(&buf2);
-			printbuf_exit(&buf1);
-			bch2_inconsistent_error(c);
-			return -1;
-		}
-
-		if (!new_s) {
-			bch2_stripes_heap_del(c, m, idx);
-
-			memset(m, 0, sizeof(*m));
-		} else {
-			stripe_to_mem(m, new_s);
-
-			if (!old_s)
-				bch2_stripes_heap_insert(c, m, idx);
-			else
-				bch2_stripes_heap_update(c, m, idx);
-		}
-	}
-
 	return 0;
 }
 
@@ -726,14 +704,15 @@ static void ec_block_endio(struct bio *bio)
 	struct bch_dev *ca = ec_bio->ca;
 	struct closure *cl = bio->bi_private;
 
-	if (bch2_dev_io_err_on(bio->bi_status, ca,
-			       bio_data_dir(bio)
-			       ? BCH_MEMBER_ERROR_write
-			       : BCH_MEMBER_ERROR_read,
-			       "erasure coding %s error: %s",
+	bch2_account_io_completion(ca, bio_data_dir(bio),
+				   ec_bio->submit_time, !bio->bi_status);
+
+	if (bio->bi_status) {
+		bch_err_dev_ratelimited(ca, "erasure coding %s error: %s",
 			       str_write_read(bio_data_dir(bio)),
-			       bch2_blk_status_to_str(bio->bi_status)))
+			       bch2_blk_status_to_str(bio->bi_status));
 		clear_bit(ec_bio->idx, ec_bio->buf->valid);
+	}
 
 	int stale = dev_ptr_stale(ca, ptr);
 	if (stale) {
@@ -796,6 +775,7 @@ static void ec_block_io(struct bch_fs *c, struct ec_stripe_buf *buf,
 		ec_bio->ca			= ca;
 		ec_bio->buf			= buf;
 		ec_bio->idx			= idx;
+		ec_bio->submit_time		= local_clock();
 
 		ec_bio->bio.bi_iter.bi_sector	= ptr->offset + buf->offset + (offset >> 9);
 		ec_bio->bio.bi_end_io		= ec_block_endio;
@@ -917,26 +897,6 @@ int bch2_ec_read_extent(struct btree_trans *trans, struct bch_read_bio *rbio,
 
 static int __ec_stripe_mem_alloc(struct bch_fs *c, size_t idx, gfp_t gfp)
 {
-	ec_stripes_heap n, *h = &c->ec_stripes_heap;
-
-	if (idx >= h->size) {
-		if (!init_heap(&n, max(1024UL, roundup_pow_of_two(idx + 1)), gfp))
-			return -BCH_ERR_ENOMEM_ec_stripe_mem_alloc;
-
-		mutex_lock(&c->ec_stripes_heap_lock);
-		if (n.size > h->size) {
-			memcpy(n.data, h->data, h->nr * sizeof(h->data[0]));
-			n.nr = h->nr;
-			swap(*h, n);
-		}
-		mutex_unlock(&c->ec_stripes_heap_lock);
-
-		free_heap(&n);
-	}
-
-	if (!genradix_ptr_alloc(&c->stripes, idx, gfp))
-		return -BCH_ERR_ENOMEM_ec_stripe_mem_alloc;
-
 	if (c->gc_pos.phase != GC_PHASE_not_running &&
 	    !genradix_ptr_alloc(&c->gc_stripes, idx, gfp))
 		return -BCH_ERR_ENOMEM_ec_stripe_mem_alloc;
@@ -1009,180 +969,50 @@ static void bch2_stripe_close(struct bch_fs *c, struct ec_stripe_new *s)
 	s->idx = 0;
 }
 
-/* Heap of all existing stripes, ordered by blocks_nonempty */
-
-static u64 stripe_idx_to_delete(struct bch_fs *c)
-{
-	ec_stripes_heap *h = &c->ec_stripes_heap;
-
-	lockdep_assert_held(&c->ec_stripes_heap_lock);
-
-	if (h->nr &&
-	    h->data[0].blocks_nonempty == 0 &&
-	    !bch2_stripe_is_open(c, h->data[0].idx))
-		return h->data[0].idx;
-
-	return 0;
-}
-
-static inline void ec_stripes_heap_set_backpointer(ec_stripes_heap *h,
-						   size_t i)
-{
-	struct bch_fs *c = container_of(h, struct bch_fs, ec_stripes_heap);
-
-	genradix_ptr(&c->stripes, h->data[i].idx)->heap_idx = i;
-}
-
-static inline bool ec_stripes_heap_cmp(const void *l, const void *r, void __always_unused *args)
-{
-	struct ec_stripe_heap_entry *_l = (struct ec_stripe_heap_entry *)l;
-	struct ec_stripe_heap_entry *_r = (struct ec_stripe_heap_entry *)r;
-
-	return ((_l->blocks_nonempty > _r->blocks_nonempty) <
-		(_l->blocks_nonempty < _r->blocks_nonempty));
-}
-
-static inline void ec_stripes_heap_swap(void *l, void *r, void *h)
-{
-	struct ec_stripe_heap_entry *_l = (struct ec_stripe_heap_entry *)l;
-	struct ec_stripe_heap_entry *_r = (struct ec_stripe_heap_entry *)r;
-	ec_stripes_heap *_h = (ec_stripes_heap *)h;
-	size_t i = _l - _h->data;
-	size_t j = _r - _h->data;
-
-	swap(*_l, *_r);
-
-	ec_stripes_heap_set_backpointer(_h, i);
-	ec_stripes_heap_set_backpointer(_h, j);
-}
-
-static const struct min_heap_callbacks callbacks = {
-	.less = ec_stripes_heap_cmp,
-	.swp = ec_stripes_heap_swap,
-};
-
-static void heap_verify_backpointer(struct bch_fs *c, size_t idx)
-{
-	ec_stripes_heap *h = &c->ec_stripes_heap;
-	struct stripe *m = genradix_ptr(&c->stripes, idx);
-
-	BUG_ON(m->heap_idx >= h->nr);
-	BUG_ON(h->data[m->heap_idx].idx != idx);
-}
-
-void bch2_stripes_heap_del(struct bch_fs *c,
-			   struct stripe *m, size_t idx)
-{
-	mutex_lock(&c->ec_stripes_heap_lock);
-	heap_verify_backpointer(c, idx);
-
-	min_heap_del(&c->ec_stripes_heap, m->heap_idx, &callbacks, &c->ec_stripes_heap);
-	mutex_unlock(&c->ec_stripes_heap_lock);
-}
-
-void bch2_stripes_heap_insert(struct bch_fs *c,
-			      struct stripe *m, size_t idx)
-{
-	mutex_lock(&c->ec_stripes_heap_lock);
-	BUG_ON(min_heap_full(&c->ec_stripes_heap));
-
-	genradix_ptr(&c->stripes, idx)->heap_idx = c->ec_stripes_heap.nr;
-	min_heap_push(&c->ec_stripes_heap, &((struct ec_stripe_heap_entry) {
-			.idx = idx,
-			.blocks_nonempty = m->blocks_nonempty,
-		}),
-		&callbacks,
-		&c->ec_stripes_heap);
-
-	heap_verify_backpointer(c, idx);
-	mutex_unlock(&c->ec_stripes_heap_lock);
-}
-
-void bch2_stripes_heap_update(struct bch_fs *c,
-			      struct stripe *m, size_t idx)
-{
-	ec_stripes_heap *h = &c->ec_stripes_heap;
-	bool do_deletes;
-	size_t i;
-
-	mutex_lock(&c->ec_stripes_heap_lock);
-	heap_verify_backpointer(c, idx);
-
-	h->data[m->heap_idx].blocks_nonempty = m->blocks_nonempty;
-
-	i = m->heap_idx;
-	min_heap_sift_up(h,	i, &callbacks, &c->ec_stripes_heap);
-	min_heap_sift_down(h, i, &callbacks, &c->ec_stripes_heap);
-
-	heap_verify_backpointer(c, idx);
-
-	do_deletes = stripe_idx_to_delete(c) != 0;
-	mutex_unlock(&c->ec_stripes_heap_lock);
-
-	if (do_deletes)
-		bch2_do_stripe_deletes(c);
-}
-
 /* stripe deletion */
 
 static int ec_stripe_delete(struct btree_trans *trans, u64 idx)
 {
-	struct bch_fs *c = trans->c;
 	struct btree_iter iter;
-	struct bkey_s_c k;
-	struct bkey_s_c_stripe s;
-	int ret;
-
-	k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_stripes, POS(0, idx),
-			       BTREE_ITER_intent);
-	ret = bkey_err(k);
+	struct bkey_s_c k = bch2_bkey_get_iter(trans, &iter,
+					       BTREE_ID_stripes, POS(0, idx),
+					       BTREE_ITER_intent);
+	int ret = bkey_err(k);
 	if (ret)
 		goto err;
 
-	if (k.k->type != KEY_TYPE_stripe) {
-		bch2_fs_inconsistent(c, "attempting to delete nonexistent stripe %llu", idx);
-		ret = -EINVAL;
-		goto err;
-	}
-
-	s = bkey_s_c_to_stripe(k);
-	for (unsigned i = 0; i < s.v->nr_blocks; i++)
-		if (stripe_blockcount_get(s.v, i)) {
-			struct printbuf buf = PRINTBUF;
-
-			bch2_bkey_val_to_text(&buf, c, k);
-			bch2_fs_inconsistent(c, "attempting to delete nonempty stripe %s", buf.buf);
-			printbuf_exit(&buf);
-			ret = -EINVAL;
-			goto err;
-		}
-
-	ret = bch2_btree_delete_at(trans, &iter, 0);
+	/*
+	 * We expect write buffer races here
+	 * Important: check stripe_is_open with stripe key locked:
+	 */
+	if (k.k->type == KEY_TYPE_stripe &&
+	    !bch2_stripe_is_open(trans->c, idx) &&
+	    stripe_lru_pos(bkey_s_c_to_stripe(k).v) == 1)
+		ret = bch2_btree_delete_at(trans, &iter, 0);
 err:
 	bch2_trans_iter_exit(trans, &iter);
 	return ret;
 }
 
+/*
+ * XXX
+ * can we kill this and delete stripes from the trigger?
+ */
 static void ec_stripe_delete_work(struct work_struct *work)
 {
 	struct bch_fs *c =
 		container_of(work, struct bch_fs, ec_stripe_delete_work);
 
-	while (1) {
-		mutex_lock(&c->ec_stripes_heap_lock);
-		u64 idx = stripe_idx_to_delete(c);
-		mutex_unlock(&c->ec_stripes_heap_lock);
-
-		if (!idx)
-			break;
-
-		int ret = bch2_trans_commit_do(c, NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
-					ec_stripe_delete(trans, idx));
-		bch_err_fn(c, ret);
-		if (ret)
-			break;
-	}
-
+	bch2_trans_run(c,
+		bch2_btree_write_buffer_tryflush(trans) ?:
+		for_each_btree_key_max_commit(trans, lru_iter, BTREE_ID_lru,
+				lru_pos(BCH_LRU_STRIPE_FRAGMENTATION, 1, 0),
+				lru_pos(BCH_LRU_STRIPE_FRAGMENTATION, 1, LRU_TIME_MAX),
+				0, lru_k,
+				NULL, NULL,
+				BCH_TRANS_COMMIT_no_enospc, ({
+			ec_stripe_delete(trans, lru_k.k->p.offset);
+		})));
 	bch2_write_ref_put(c, BCH_WRITE_REF_stripe_delete);
 }
 
@@ -1294,7 +1124,7 @@ static int ec_stripe_update_extent(struct btree_trans *trans,
 
 		bch2_fs_inconsistent(c, "%s", buf.buf);
 		printbuf_exit(&buf);
-		return -EIO;
+		return -BCH_ERR_erasure_coding_found_btree_node;
 	}
 
 	k = bch2_backpointer_get_key(trans, bp, &iter, BTREE_ITER_intent, last_flushed);
@@ -1360,7 +1190,7 @@ static int ec_stripe_update_bucket(struct btree_trans *trans, struct ec_stripe_b
 
 	struct bch_dev *ca = bch2_dev_tryget(c, ptr.dev);
 	if (!ca)
-		return -EIO;
+		return -BCH_ERR_ENOENT_dev_not_found;
 
 	struct bpos bucket_pos = PTR_BUCKET_POS(ca, &ptr);
 
@@ -1380,8 +1210,12 @@ static int ec_stripe_update_bucket(struct btree_trans *trans, struct ec_stripe_b
 		if (bp_k.k->type != KEY_TYPE_backpointer)
 			continue;
 
+		struct bkey_s_c_backpointer bp = bkey_s_c_to_backpointer(bp_k);
+		if (bp.v->btree_id == BTREE_ID_stripes)
+			continue;
+
 		ec_stripe_update_extent(trans, ca, bucket_pos, ptr.gen, s,
-					bkey_s_c_to_backpointer(bp_k), &last_flushed);
+					bp, &last_flushed);
 	}));
 
 	bch2_bkey_buf_exit(&last_flushed, c);
@@ -1393,21 +1227,19 @@ static int ec_stripe_update_extents(struct bch_fs *c, struct ec_stripe_buf *s)
 {
 	struct btree_trans *trans = bch2_trans_get(c);
 	struct bch_stripe *v = &bkey_i_to_stripe(&s->key)->v;
-	unsigned i, nr_data = v->nr_blocks - v->nr_redundant;
-	int ret = 0;
+	unsigned nr_data = v->nr_blocks - v->nr_redundant;
 
-	ret = bch2_btree_write_buffer_flush_sync(trans);
+	int ret = bch2_btree_write_buffer_flush_sync(trans);
 	if (ret)
 		goto err;
 
-	for (i = 0; i < nr_data; i++) {
+	for (unsigned i = 0; i < nr_data; i++) {
 		ret = ec_stripe_update_bucket(trans, s, i);
 		if (ret)
 			break;
 	}
 err:
 	bch2_trans_put(trans);
-
 	return ret;
 }
 
@@ -1473,6 +1305,7 @@ static void ec_stripe_create(struct ec_stripe_new *s)
 	if (s->err) {
 		if (!bch2_err_matches(s->err, EROFS))
 			bch_err(c, "error creating stripe: error writing data buckets");
+		ret = s->err;
 		goto err;
 	}
 
@@ -1481,6 +1314,7 @@ static void ec_stripe_create(struct ec_stripe_new *s)
 
 		if (ec_do_recov(c, &s->existing_stripe)) {
 			bch_err(c, "error creating stripe: error reading existing stripe");
+			ret = -BCH_ERR_ec_block_read;
 			goto err;
 		}
 
@@ -1506,6 +1340,7 @@ static void ec_stripe_create(struct ec_stripe_new *s)
 
 	if (ec_nr_failed(&s->new_stripe)) {
 		bch_err(c, "error creating stripe: error writing redundancy buckets");
+		ret = -BCH_ERR_ec_block_write;
 		goto err;
 	}
 
@@ -1527,6 +1362,8 @@ static void ec_stripe_create(struct ec_stripe_new *s)
 	if (ret)
 		goto err;
 err:
+	trace_stripe_create(c, s->idx, ret);
+
 	bch2_disk_reservation_put(c, &s->res);
 
 	for (i = 0; i < v->nr_blocks; i++)
@@ -1612,11 +1449,11 @@ static void ec_stripe_new_cancel(struct bch_fs *c, struct ec_stripe_head *h, int
 	ec_stripe_new_set_pending(c, h);
 }
 
-void bch2_ec_bucket_cancel(struct bch_fs *c, struct open_bucket *ob)
+void bch2_ec_bucket_cancel(struct bch_fs *c, struct open_bucket *ob, int err)
 {
 	struct ec_stripe_new *s = ob->ec;
 
-	s->err = -EIO;
+	s->err = err;
 }
 
 void *bch2_writepoint_ec_buf(struct bch_fs *c, struct write_point *wp)
@@ -1968,39 +1805,40 @@ static int new_stripe_alloc_buckets(struct btree_trans *trans,
 	return 0;
 }
 
-static s64 get_existing_stripe(struct bch_fs *c,
-			       struct ec_stripe_head *head)
+static int __get_existing_stripe(struct btree_trans *trans,
+				 struct ec_stripe_head *head,
+				 struct ec_stripe_buf *stripe,
+				 u64 idx)
 {
-	ec_stripes_heap *h = &c->ec_stripes_heap;
-	struct stripe *m;
-	size_t heap_idx;
-	u64 stripe_idx;
-	s64 ret = -1;
-
-	if (may_create_new_stripe(c))
-		return -1;
+	struct bch_fs *c = trans->c;
 
-	mutex_lock(&c->ec_stripes_heap_lock);
-	for (heap_idx = 0; heap_idx < h->nr; heap_idx++) {
-		/* No blocks worth reusing, stripe will just be deleted: */
-		if (!h->data[heap_idx].blocks_nonempty)
-			continue;
+	struct btree_iter iter;
+	struct bkey_s_c k = bch2_bkey_get_iter(trans, &iter,
+					  BTREE_ID_stripes, POS(0, idx), 0);
+	int ret = bkey_err(k);
+	if (ret)
+		goto err;
 
-		stripe_idx = h->data[heap_idx].idx;
+	/* We expect write buffer races here */
+	if (k.k->type != KEY_TYPE_stripe)
+		goto out;
 
-		m = genradix_ptr(&c->stripes, stripe_idx);
+	struct bkey_s_c_stripe s = bkey_s_c_to_stripe(k);
+	if (stripe_lru_pos(s.v) <= 1)
+		goto out;
 
-		if (m->disk_label	== head->disk_label &&
-		    m->algorithm	== head->algo &&
-		    m->nr_redundant	== head->redundancy &&
-		    m->sectors		== head->blocksize &&
-		    m->blocks_nonempty	< m->nr_blocks - m->nr_redundant &&
-		    bch2_try_open_stripe(c, head->s, stripe_idx)) {
-			ret = stripe_idx;
-			break;
-		}
+	if (s.v->disk_label		== head->disk_label &&
+	    s.v->algorithm		== head->algo &&
+	    s.v->nr_redundant		== head->redundancy &&
+	    le16_to_cpu(s.v->sectors)	== head->blocksize &&
+	    bch2_try_open_stripe(c, head->s, idx)) {
+		bkey_reassemble(&stripe->key, k);
+		ret = 1;
 	}
-	mutex_unlock(&c->ec_stripes_heap_lock);
+out:
+	bch2_set_btree_iter_dontneed(&iter);
+err:
+	bch2_trans_iter_exit(trans, &iter);
 	return ret;
 }
 
@@ -2052,24 +1890,33 @@ static int __bch2_ec_stripe_head_reuse(struct btree_trans *trans, struct ec_stri
 				       struct ec_stripe_new *s)
 {
 	struct bch_fs *c = trans->c;
-	s64 idx;
-	int ret;
 
 	/*
 	 * If we can't allocate a new stripe, and there's no stripes with empty
 	 * blocks for us to reuse, that means we have to wait on copygc:
 	 */
-	idx = get_existing_stripe(c, h);
-	if (idx < 0)
-		return -BCH_ERR_stripe_alloc_blocked;
+	if (may_create_new_stripe(c))
+		return -1;
 
-	ret = get_stripe_key_trans(trans, idx, &s->existing_stripe);
-	bch2_fs_fatal_err_on(ret && !bch2_err_matches(ret, BCH_ERR_transaction_restart), c,
-			     "reading stripe key: %s", bch2_err_str(ret));
-	if (ret) {
-		bch2_stripe_close(c, s);
-		return ret;
+	struct btree_iter lru_iter;
+	struct bkey_s_c lru_k;
+	int ret = 0;
+
+	for_each_btree_key_max_norestart(trans, lru_iter, BTREE_ID_lru,
+			lru_pos(BCH_LRU_STRIPE_FRAGMENTATION, 2, 0),
+			lru_pos(BCH_LRU_STRIPE_FRAGMENTATION, 2, LRU_TIME_MAX),
+			0, lru_k, ret) {
+		ret = __get_existing_stripe(trans, h, &s->existing_stripe, lru_k.k->p.offset);
+		if (ret)
+			break;
 	}
+	bch2_trans_iter_exit(trans, &lru_iter);
+	if (!ret)
+		ret = -BCH_ERR_stripe_alloc_blocked;
+	if (ret == 1)
+		ret = 0;
+	if (ret)
+		return ret;
 
 	return init_new_stripe_from_existing(c, s);
 }
@@ -2367,46 +2214,7 @@ void bch2_fs_ec_flush(struct bch_fs *c)
 
 int bch2_stripes_read(struct bch_fs *c)
 {
-	int ret = bch2_trans_run(c,
-		for_each_btree_key(trans, iter, BTREE_ID_stripes, POS_MIN,
-				   BTREE_ITER_prefetch, k, ({
-			if (k.k->type != KEY_TYPE_stripe)
-				continue;
-
-			ret = __ec_stripe_mem_alloc(c, k.k->p.offset, GFP_KERNEL);
-			if (ret)
-				break;
-
-			struct stripe *m = genradix_ptr(&c->stripes, k.k->p.offset);
-
-			stripe_to_mem(m, bkey_s_c_to_stripe(k).v);
-
-			bch2_stripes_heap_insert(c, m, k.k->p.offset);
-			0;
-		})));
-	bch_err_fn(c, ret);
-	return ret;
-}
-
-void bch2_stripes_heap_to_text(struct printbuf *out, struct bch_fs *c)
-{
-	ec_stripes_heap *h = &c->ec_stripes_heap;
-	struct stripe *m;
-	size_t i;
-
-	mutex_lock(&c->ec_stripes_heap_lock);
-	for (i = 0; i < min_t(size_t, h->nr, 50); i++) {
-		m = genradix_ptr(&c->stripes, h->data[i].idx);
-
-		prt_printf(out, "%zu %u/%u+%u", h->data[i].idx,
-		       h->data[i].blocks_nonempty,
-		       m->nr_blocks - m->nr_redundant,
-		       m->nr_redundant);
-		if (bch2_stripe_is_open(c, h->data[i].idx))
-			prt_str(out, " open");
-		prt_newline(out);
-	}
-	mutex_unlock(&c->ec_stripes_heap_lock);
+	return 0;
 }
 
 static void bch2_new_stripe_to_text(struct printbuf *out, struct bch_fs *c,
@@ -2477,15 +2285,12 @@ void bch2_fs_ec_exit(struct bch_fs *c)
 
 	BUG_ON(!list_empty(&c->ec_stripe_new_list));
 
-	free_heap(&c->ec_stripes_heap);
-	genradix_free(&c->stripes);
 	bioset_exit(&c->ec_bioset);
 }
 
 void bch2_fs_ec_init_early(struct bch_fs *c)
 {
 	spin_lock_init(&c->ec_stripes_new_lock);
-	mutex_init(&c->ec_stripes_heap_lock);
 
 	INIT_LIST_HEAD(&c->ec_stripe_head_list);
 	mutex_init(&c->ec_stripe_head_lock);
@@ -2503,3 +2308,40 @@ int bch2_fs_ec_init(struct bch_fs *c)
 	return bioset_init(&c->ec_bioset, 1, offsetof(struct ec_bio, bio),
 			   BIOSET_NEED_BVECS);
 }
+
+static int bch2_check_stripe_to_lru_ref(struct btree_trans *trans,
+					struct bkey_s_c k,
+					struct bkey_buf *last_flushed)
+{
+	if (k.k->type != KEY_TYPE_stripe)
+		return 0;
+
+	struct bkey_s_c_stripe s = bkey_s_c_to_stripe(k);
+
+	u64 lru_idx = stripe_lru_pos(s.v);
+	if (lru_idx) {
+		int ret = bch2_lru_check_set(trans, BCH_LRU_STRIPE_FRAGMENTATION,
+					     k.k->p.offset, lru_idx, k, last_flushed);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
+int bch2_check_stripe_to_lru_refs(struct bch_fs *c)
+{
+	struct bkey_buf last_flushed;
+
+	bch2_bkey_buf_init(&last_flushed);
+	bkey_init(&last_flushed.k->k);
+
+	int ret = bch2_trans_run(c,
+		for_each_btree_key_commit(trans, iter, BTREE_ID_stripes,
+				POS_MIN, BTREE_ITER_prefetch, k,
+				NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
+			bch2_check_stripe_to_lru_ref(trans, k, &last_flushed)));
+
+	bch2_bkey_buf_exit(&last_flushed, c);
+	bch_err_fn(c, ret);
+	return ret;
+}
diff --git a/fs/bcachefs/ec.h b/fs/bcachefs/ec.h
index 583ca6a226da..62d27e04d763 100644
--- a/fs/bcachefs/ec.h
+++ b/fs/bcachefs/ec.h
@@ -92,6 +92,29 @@ static inline void stripe_csum_set(struct bch_stripe *s,
 	memcpy(stripe_csum(s, block, csum_idx), &csum, bch_crc_bytes[s->csum_type]);
 }
 
+#define STRIPE_LRU_POS_EMPTY	1
+
+static inline u64 stripe_lru_pos(const struct bch_stripe *s)
+{
+	if (!s)
+		return 0;
+
+	unsigned nr_data = s->nr_blocks - s->nr_redundant, blocks_empty = 0;
+
+	for (unsigned i = 0; i < nr_data; i++)
+		blocks_empty += !stripe_blockcount_get(s, i);
+
+	/* Will be picked up by the stripe_delete worker */
+	if (blocks_empty == nr_data)
+		return STRIPE_LRU_POS_EMPTY;
+
+	if (!blocks_empty)
+		return 0;
+
+	/* invert: more blocks empty = reuse first */
+	return LRU_TIME_MAX - blocks_empty;
+}
+
 static inline bool __bch2_ptr_matches_stripe(const struct bch_extent_ptr *stripe_ptr,
 					     const struct bch_extent_ptr *data_ptr,
 					     unsigned sectors)
@@ -132,6 +155,20 @@ static inline bool bch2_ptr_matches_stripe_m(const struct gc_stripe *m,
 					 m->sectors);
 }
 
+static inline void gc_stripe_unlock(struct gc_stripe *s)
+{
+	BUILD_BUG_ON(!((union ulong_byte_assert) { .ulong = 1UL << BUCKET_LOCK_BITNR }).byte);
+
+	clear_bit_unlock(BUCKET_LOCK_BITNR, (void *) &s->lock);
+	wake_up_bit((void *) &s->lock, BUCKET_LOCK_BITNR);
+}
+
+static inline void gc_stripe_lock(struct gc_stripe *s)
+{
+	wait_on_bit_lock((void *) &s->lock, BUCKET_LOCK_BITNR,
+			 TASK_UNINTERRUPTIBLE);
+}
+
 struct bch_read_bio;
 
 struct ec_stripe_buf {
@@ -212,7 +249,7 @@ int bch2_ec_read_extent(struct btree_trans *, struct bch_read_bio *, struct bkey
 
 void *bch2_writepoint_ec_buf(struct bch_fs *, struct write_point *);
 
-void bch2_ec_bucket_cancel(struct bch_fs *, struct open_bucket *);
+void bch2_ec_bucket_cancel(struct bch_fs *, struct open_bucket *, int);
 
 int bch2_ec_stripe_new_alloc(struct bch_fs *, struct ec_stripe_head *);
 
@@ -221,10 +258,6 @@ struct ec_stripe_head *bch2_ec_stripe_head_get(struct btree_trans *,
 			unsigned, unsigned, unsigned,
 			enum bch_watermark, struct closure *);
 
-void bch2_stripes_heap_update(struct bch_fs *, struct stripe *, size_t);
-void bch2_stripes_heap_del(struct bch_fs *, struct stripe *, size_t);
-void bch2_stripes_heap_insert(struct bch_fs *, struct stripe *, size_t);
-
 void bch2_do_stripe_deletes(struct bch_fs *);
 void bch2_ec_do_stripe_creates(struct bch_fs *);
 void bch2_ec_stripe_new_free(struct bch_fs *, struct ec_stripe_new *);
@@ -261,11 +294,12 @@ void bch2_fs_ec_flush(struct bch_fs *);
 
 int bch2_stripes_read(struct bch_fs *);
 
-void bch2_stripes_heap_to_text(struct printbuf *, struct bch_fs *);
 void bch2_new_stripes_to_text(struct printbuf *, struct bch_fs *);
 
 void bch2_fs_ec_exit(struct bch_fs *);
 void bch2_fs_ec_init_early(struct bch_fs *);
 int bch2_fs_ec_init(struct bch_fs *);
 
+int bch2_check_stripe_to_lru_refs(struct bch_fs *);
+
 #endif /* _BCACHEFS_EC_H */
diff --git a/fs/bcachefs/ec_types.h b/fs/bcachefs/ec_types.h
index 8d1e70e830ac..06144bfd9c19 100644
--- a/fs/bcachefs/ec_types.h
+++ b/fs/bcachefs/ec_types.h
@@ -20,23 +20,15 @@ struct stripe {
 };
 
 struct gc_stripe {
+	u8			lock;
+	unsigned		alive:1; /* does a corresponding key exist in stripes btree? */
 	u16			sectors;
-
 	u8			nr_blocks;
 	u8			nr_redundant;
-
-	unsigned		alive:1; /* does a corresponding key exist in stripes btree? */
 	u16			block_sectors[BCH_BKEY_PTRS_MAX];
 	struct bch_extent_ptr	ptrs[BCH_BKEY_PTRS_MAX];
 
 	struct bch_replicas_padded r;
 };
 
-struct ec_stripe_heap_entry {
-	size_t			idx;
-	unsigned		blocks_nonempty;
-};
-
-typedef DEFINE_MIN_HEAP(struct ec_stripe_heap_entry, ec_stripes_heap) ec_stripes_heap;
-
 #endif /* _BCACHEFS_EC_TYPES_H */
diff --git a/fs/bcachefs/errcode.h b/fs/bcachefs/errcode.h
index 4590cd0c7c90..101806d7ebe1 100644
--- a/fs/bcachefs/errcode.h
+++ b/fs/bcachefs/errcode.h
@@ -116,9 +116,11 @@
 	x(ENOENT,			ENOENT_snapshot_tree)			\
 	x(ENOENT,			ENOENT_dirent_doesnt_match_inode)	\
 	x(ENOENT,			ENOENT_dev_not_found)			\
+	x(ENOENT,			ENOENT_dev_bucket_not_found)		\
 	x(ENOENT,			ENOENT_dev_idx_not_found)		\
 	x(ENOENT,			ENOENT_inode_no_backpointer)		\
 	x(ENOENT,			ENOENT_no_snapshot_tree_subvol)		\
+	x(ENOENT,			btree_node_dying)			\
 	x(ENOTEMPTY,			ENOTEMPTY_dir_not_empty)		\
 	x(ENOTEMPTY,			ENOTEMPTY_subvol_not_empty)		\
 	x(EEXIST,			EEXIST_str_hash_set)			\
@@ -180,6 +182,12 @@
 	x(EINVAL,			not_in_recovery)			\
 	x(EINVAL,			cannot_rewind_recovery)			\
 	x(0,				data_update_done)			\
+	x(BCH_ERR_data_update_done,	data_update_done_would_block)		\
+	x(BCH_ERR_data_update_done,	data_update_done_unwritten)		\
+	x(BCH_ERR_data_update_done,	data_update_done_no_writes_needed)	\
+	x(BCH_ERR_data_update_done,	data_update_done_no_snapshot)		\
+	x(BCH_ERR_data_update_done,	data_update_done_no_dev_refs)		\
+	x(BCH_ERR_data_update_done,	data_update_done_no_rw_devs)		\
 	x(EINVAL,			device_state_not_allowed)		\
 	x(EINVAL,			member_info_missing)			\
 	x(EINVAL,			mismatched_block_size)			\
@@ -200,6 +208,8 @@
 	x(EINVAL,			no_resize_with_buckets_nouse)		\
 	x(EINVAL,			inode_unpack_error)			\
 	x(EINVAL,			varint_decode_error)			\
+	x(EINVAL,			erasure_coding_found_btree_node)	\
+	x(EOPNOTSUPP,			may_not_use_incompat_feature)		\
 	x(EROFS,			erofs_trans_commit)			\
 	x(EROFS,			erofs_no_writes)			\
 	x(EROFS,			erofs_journal_err)			\
@@ -210,10 +220,18 @@
 	x(EROFS,			insufficient_devices)			\
 	x(0,				operation_blocked)			\
 	x(BCH_ERR_operation_blocked,	btree_cache_cannibalize_lock_blocked)	\
-	x(BCH_ERR_operation_blocked,	journal_res_get_blocked)		\
-	x(BCH_ERR_operation_blocked,	journal_preres_get_blocked)		\
-	x(BCH_ERR_operation_blocked,	bucket_alloc_blocked)			\
-	x(BCH_ERR_operation_blocked,	stripe_alloc_blocked)			\
+	x(BCH_ERR_operation_blocked,	journal_res_blocked)			\
+	x(BCH_ERR_journal_res_blocked,	journal_blocked)			\
+	x(BCH_ERR_journal_res_blocked,	journal_max_in_flight)			\
+	x(BCH_ERR_journal_res_blocked,	journal_max_open)			\
+	x(BCH_ERR_journal_res_blocked,	journal_full)				\
+	x(BCH_ERR_journal_res_blocked,	journal_pin_full)			\
+	x(BCH_ERR_journal_res_blocked,	journal_buf_enomem)			\
+	x(BCH_ERR_journal_res_blocked,	journal_stuck)				\
+	x(BCH_ERR_journal_res_blocked,	journal_retry_open)			\
+	x(BCH_ERR_journal_res_blocked,	journal_preres_get_blocked)		\
+	x(BCH_ERR_journal_res_blocked,	bucket_alloc_blocked)			\
+	x(BCH_ERR_journal_res_blocked,	stripe_alloc_blocked)			\
 	x(BCH_ERR_invalid,		invalid_sb)				\
 	x(BCH_ERR_invalid_sb,		invalid_sb_magic)			\
 	x(BCH_ERR_invalid_sb,		invalid_sb_version)			\
@@ -223,6 +241,7 @@
 	x(BCH_ERR_invalid_sb,		invalid_sb_csum)			\
 	x(BCH_ERR_invalid_sb,		invalid_sb_block_size)			\
 	x(BCH_ERR_invalid_sb,		invalid_sb_uuid)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_offset)			\
 	x(BCH_ERR_invalid_sb,		invalid_sb_too_many_members)		\
 	x(BCH_ERR_invalid_sb,		invalid_sb_dev_idx)			\
 	x(BCH_ERR_invalid_sb,		invalid_sb_time_precision)		\
@@ -250,6 +269,7 @@
 	x(BCH_ERR_operation_blocked,    nocow_lock_blocked)			\
 	x(EIO,				journal_shutdown)			\
 	x(EIO,				journal_flush_err)			\
+	x(EIO,				journal_write_err)			\
 	x(EIO,				btree_node_read_err)			\
 	x(BCH_ERR_btree_node_read_err,	btree_node_read_err_cached)		\
 	x(EIO,				sb_not_downgraded)			\
@@ -258,17 +278,52 @@
 	x(EIO,				btree_node_read_validate_error)		\
 	x(EIO,				btree_need_topology_repair)		\
 	x(EIO,				bucket_ref_update)			\
+	x(EIO,				trigger_alloc)				\
 	x(EIO,				trigger_pointer)			\
 	x(EIO,				trigger_stripe_pointer)			\
 	x(EIO,				metadata_bucket_inconsistency)		\
 	x(EIO,				mark_stripe)				\
 	x(EIO,				stripe_reconstruct)			\
 	x(EIO,				key_type_error)				\
-	x(EIO,				no_device_to_read_from)			\
+	x(EIO,				extent_poisened)			\
 	x(EIO,				missing_indirect_extent)		\
 	x(EIO,				invalidate_stripe_to_dev)		\
 	x(EIO,				no_encryption_key)			\
 	x(EIO,				insufficient_journal_devices)		\
+	x(EIO,				device_offline)				\
+	x(EIO,				EIO_fault_injected)			\
+	x(EIO,				ec_block_read)				\
+	x(EIO,				ec_block_write)				\
+	x(EIO,				recompute_checksum)			\
+	x(EIO,				decompress)				\
+	x(BCH_ERR_decompress,		decompress_exceeded_max_encoded_extent)	\
+	x(BCH_ERR_decompress,		decompress_lz4)				\
+	x(BCH_ERR_decompress,		decompress_gzip)			\
+	x(BCH_ERR_decompress,		decompress_zstd_src_len_bad)		\
+	x(BCH_ERR_decompress,		decompress_zstd)			\
+	x(EIO,				data_write)				\
+	x(BCH_ERR_data_write,		data_write_io)				\
+	x(BCH_ERR_data_write,		data_write_csum)			\
+	x(BCH_ERR_data_write,		data_write_invalid_ptr)			\
+	x(BCH_ERR_data_write,		data_write_misaligned)			\
+	x(BCH_ERR_decompress,		data_read)				\
+	x(BCH_ERR_data_read,		no_device_to_read_from)			\
+	x(BCH_ERR_data_read,		data_read_io_err)			\
+	x(BCH_ERR_data_read,		data_read_csum_err)			\
+	x(BCH_ERR_data_read,		data_read_retry)			\
+	x(BCH_ERR_data_read_retry,	data_read_retry_avoid)			\
+	x(BCH_ERR_data_read_retry_avoid,data_read_retry_device_offline)		\
+	x(BCH_ERR_data_read_retry_avoid,data_read_retry_io_err)			\
+	x(BCH_ERR_data_read_retry_avoid,data_read_retry_ec_reconstruct_err)	\
+	x(BCH_ERR_data_read_retry_avoid,data_read_retry_csum_err)		\
+	x(BCH_ERR_data_read_retry,	data_read_retry_csum_err_maybe_userspace)\
+	x(BCH_ERR_data_read,		data_read_decompress_err)		\
+	x(BCH_ERR_data_read,		data_read_decrypt_err)			\
+	x(BCH_ERR_data_read,		data_read_ptr_stale_race)		\
+	x(BCH_ERR_data_read_retry,	data_read_ptr_stale_retry)		\
+	x(BCH_ERR_data_read,		data_read_no_encryption_key)		\
+	x(BCH_ERR_data_read,		data_read_buffer_too_small)		\
+	x(BCH_ERR_data_read,		data_read_key_overwritten)		\
 	x(BCH_ERR_btree_node_read_err,	btree_node_read_err_fixable)		\
 	x(BCH_ERR_btree_node_read_err,	btree_node_read_err_want_retry)		\
 	x(BCH_ERR_btree_node_read_err,	btree_node_read_err_must_retry)		\
diff --git a/fs/bcachefs/error.c b/fs/bcachefs/error.c
index 038da6a61f6b..207f35d3cce2 100644
--- a/fs/bcachefs/error.c
+++ b/fs/bcachefs/error.c
@@ -3,8 +3,8 @@
 #include "btree_cache.h"
 #include "btree_iter.h"
 #include "error.h"
-#include "fs-common.h"
 #include "journal.h"
+#include "namei.h"
 #include "recovery_passes.h"
 #include "super.h"
 #include "thread_with_file.h"
@@ -54,25 +54,41 @@ void bch2_io_error_work(struct work_struct *work)
 {
 	struct bch_dev *ca = container_of(work, struct bch_dev, io_error_work);
 	struct bch_fs *c = ca->fs;
-	bool dev;
+
+	/* XXX: if it's reads or checksums that are failing, set it to failed */
 
 	down_write(&c->state_lock);
-	dev = bch2_dev_state_allowed(c, ca, BCH_MEMBER_STATE_ro,
-				    BCH_FORCE_IF_DEGRADED);
-	if (dev
-	    ? __bch2_dev_set_state(c, ca, BCH_MEMBER_STATE_ro,
-				  BCH_FORCE_IF_DEGRADED)
-	    : bch2_fs_emergency_read_only(c))
+	unsigned long write_errors_start = READ_ONCE(ca->write_errors_start);
+
+	if (write_errors_start &&
+	    time_after(jiffies,
+		       write_errors_start + c->opts.write_error_timeout * HZ)) {
+		if (ca->mi.state >= BCH_MEMBER_STATE_ro)
+			goto out;
+
+		bool dev = !__bch2_dev_set_state(c, ca, BCH_MEMBER_STATE_ro,
+						 BCH_FORCE_IF_DEGRADED);
+
 		bch_err(ca,
-			"too many IO errors, setting %s RO",
+			"writes erroring for %u seconds, setting %s ro",
+			c->opts.write_error_timeout,
 			dev ? "device" : "filesystem");
+		if (!dev)
+			bch2_fs_emergency_read_only(c);
+
+	}
+out:
 	up_write(&c->state_lock);
 }
 
 void bch2_io_error(struct bch_dev *ca, enum bch_member_error_type type)
 {
 	atomic64_inc(&ca->errors[type]);
-	//queue_work(system_long_wq, &ca->io_error_work);
+
+	if (type == BCH_MEMBER_ERROR_write && !ca->write_errors_start)
+		ca->write_errors_start = jiffies;
+
+	queue_work(system_long_wq, &ca->io_error_work);
 }
 
 enum ask_yn {
@@ -530,35 +546,59 @@ void bch2_flush_fsck_errs(struct bch_fs *c)
 	mutex_unlock(&c->fsck_error_msgs_lock);
 }
 
-int bch2_inum_err_msg_trans(struct btree_trans *trans, struct printbuf *out, subvol_inum inum)
+int bch2_inum_offset_err_msg_trans(struct btree_trans *trans, struct printbuf *out,
+				    subvol_inum inum, u64 offset)
 {
 	u32 restart_count = trans->restart_count;
 	int ret = 0;
 
-	/* XXX: we don't yet attempt to print paths when we don't know the subvol */
-	if (inum.subvol)
-		ret = lockrestart_do(trans, bch2_inum_to_path(trans, inum, out));
+	if (inum.subvol) {
+		ret = bch2_inum_to_path(trans, inum, out);
+		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
+			return ret;
+	}
 	if (!inum.subvol || ret)
 		prt_printf(out, "inum %llu:%llu", inum.subvol, inum.inum);
+	prt_printf(out, " offset %llu: ", offset);
 
 	return trans_was_restarted(trans, restart_count);
 }
 
-int bch2_inum_offset_err_msg_trans(struct btree_trans *trans, struct printbuf *out,
-				    subvol_inum inum, u64 offset)
+void bch2_inum_offset_err_msg(struct bch_fs *c, struct printbuf *out,
+			      subvol_inum inum, u64 offset)
 {
-	int ret = bch2_inum_err_msg_trans(trans, out, inum);
-	prt_printf(out, " offset %llu: ", offset);
-	return ret;
+	bch2_trans_do(c, bch2_inum_offset_err_msg_trans(trans, out, inum, offset));
 }
 
-void bch2_inum_err_msg(struct bch_fs *c, struct printbuf *out, subvol_inum inum)
+int bch2_inum_snap_offset_err_msg_trans(struct btree_trans *trans, struct printbuf *out,
+					struct bpos pos)
 {
-	bch2_trans_run(c, bch2_inum_err_msg_trans(trans, out, inum));
+	struct bch_fs *c = trans->c;
+	int ret = 0;
+
+	if (!bch2_snapshot_is_leaf(c, pos.snapshot))
+		prt_str(out, "(multiple snapshots) ");
+
+	subvol_inum inum = {
+		.subvol	= bch2_snapshot_tree_oldest_subvol(c, pos.snapshot),
+		.inum	= pos.inode,
+	};
+
+	if (inum.subvol) {
+		ret = bch2_inum_to_path(trans, inum, out);
+		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
+			return ret;
+	}
+
+	if (!inum.subvol || ret)
+		prt_printf(out, "inum %llu:%u", pos.inode, pos.snapshot);
+
+	prt_printf(out, " offset %llu: ", pos.offset << 8);
+	return 0;
 }
 
-void bch2_inum_offset_err_msg(struct bch_fs *c, struct printbuf *out,
-			      subvol_inum inum, u64 offset)
+void bch2_inum_snap_offset_err_msg(struct bch_fs *c, struct printbuf *out,
+				  struct bpos pos)
 {
-	bch2_trans_run(c, bch2_inum_offset_err_msg_trans(trans, out, inum, offset));
+	bch2_trans_do(c, bch2_inum_snap_offset_err_msg_trans(trans, out, pos));
 }
diff --git a/fs/bcachefs/error.h b/fs/bcachefs/error.h
index 7acf2a27ca28..7d3f0e2a5fd6 100644
--- a/fs/bcachefs/error.h
+++ b/fs/bcachefs/error.h
@@ -216,32 +216,43 @@ void bch2_io_error_work(struct work_struct *);
 /* Does the error handling without logging a message */
 void bch2_io_error(struct bch_dev *, enum bch_member_error_type);
 
-#define bch2_dev_io_err_on(cond, ca, _type, ...)			\
-({									\
-	bool _ret = (cond);						\
-									\
-	if (_ret) {							\
-		bch_err_dev_ratelimited(ca, __VA_ARGS__);		\
-		bch2_io_error(ca, _type);				\
-	}								\
-	_ret;								\
-})
-
-#define bch2_dev_inum_io_err_on(cond, ca, _type, ...)			\
-({									\
-	bool _ret = (cond);						\
-									\
-	if (_ret) {							\
-		bch_err_inum_offset_ratelimited(ca, __VA_ARGS__);	\
-		bch2_io_error(ca, _type);				\
-	}								\
-	_ret;								\
-})
+#ifndef CONFIG_BCACHEFS_NO_LATENCY_ACCT
+void bch2_latency_acct(struct bch_dev *, u64, int);
+#else
+static inline void bch2_latency_acct(struct bch_dev *ca, u64 submit_time, int rw) {}
+#endif
+
+static inline void bch2_account_io_success_fail(struct bch_dev *ca,
+						enum bch_member_error_type type,
+						bool success)
+{
+	if (likely(success)) {
+		if (type == BCH_MEMBER_ERROR_write &&
+		    ca->write_errors_start)
+			ca->write_errors_start = 0;
+	} else {
+		bch2_io_error(ca, type);
+	}
+}
+
+static inline void bch2_account_io_completion(struct bch_dev *ca,
+					      enum bch_member_error_type type,
+					      u64 submit_time, bool success)
+{
+	if (unlikely(!ca))
+		return;
+
+	if (type != BCH_MEMBER_ERROR_checksum)
+		bch2_latency_acct(ca, submit_time, type);
+
+	bch2_account_io_success_fail(ca, type, success);
+}
 
-int bch2_inum_err_msg_trans(struct btree_trans *, struct printbuf *, subvol_inum);
 int bch2_inum_offset_err_msg_trans(struct btree_trans *, struct printbuf *, subvol_inum, u64);
 
-void bch2_inum_err_msg(struct bch_fs *, struct printbuf *, subvol_inum);
 void bch2_inum_offset_err_msg(struct bch_fs *, struct printbuf *, subvol_inum, u64);
 
+int bch2_inum_snap_offset_err_msg_trans(struct btree_trans *, struct printbuf *, struct bpos);
+void bch2_inum_snap_offset_err_msg(struct bch_fs *, struct printbuf *, struct bpos);
+
 #endif /* _BCACHEFS_ERROR_H */
diff --git a/fs/bcachefs/extents.c b/fs/bcachefs/extents.c
index 2d8042f853dc..ca2073db472b 100644
--- a/fs/bcachefs/extents.c
+++ b/fs/bcachefs/extents.c
@@ -28,6 +28,13 @@
 #include "trace.h"
 #include "util.h"
 
+static const char * const bch2_extent_flags_strs[] = {
+#define x(n, v)	[BCH_EXTENT_FLAG_##n] = #n,
+	BCH_EXTENT_FLAGS()
+#undef x
+	NULL,
+};
+
 static unsigned bch2_crc_field_size_max[] = {
 	[BCH_EXTENT_ENTRY_crc32] = CRC32_SIZE_MAX,
 	[BCH_EXTENT_ENTRY_crc64] = CRC64_SIZE_MAX,
@@ -51,7 +58,8 @@ struct bch_dev_io_failures *bch2_dev_io_failures(struct bch_io_failures *f,
 }
 
 void bch2_mark_io_failure(struct bch_io_failures *failed,
-			  struct extent_ptr_decoded *p)
+			  struct extent_ptr_decoded *p,
+			  bool csum_error)
 {
 	struct bch_dev_io_failures *f = bch2_dev_io_failures(failed, p->ptr.dev);
 
@@ -59,53 +67,57 @@ void bch2_mark_io_failure(struct bch_io_failures *failed,
 		BUG_ON(failed->nr >= ARRAY_SIZE(failed->devs));
 
 		f = &failed->devs[failed->nr++];
-		f->dev		= p->ptr.dev;
-		f->idx		= p->idx;
-		f->nr_failed	= 1;
-		f->nr_retries	= 0;
-	} else if (p->idx != f->idx) {
-		f->idx		= p->idx;
-		f->nr_failed	= 1;
-		f->nr_retries	= 0;
-	} else {
-		f->nr_failed++;
+		memset(f, 0, sizeof(*f));
+		f->dev = p->ptr.dev;
 	}
+
+	if (p->do_ec_reconstruct)
+		f->failed_ec = true;
+	else if (!csum_error)
+		f->failed_io = true;
+	else
+		f->failed_csum_nr++;
 }
 
-static inline u64 dev_latency(struct bch_fs *c, unsigned dev)
+static inline u64 dev_latency(struct bch_dev *ca)
 {
-	struct bch_dev *ca = bch2_dev_rcu(c, dev);
 	return ca ? atomic64_read(&ca->cur_latency[READ]) : S64_MAX;
 }
 
+static inline int dev_failed(struct bch_dev *ca)
+{
+	return !ca || ca->mi.state == BCH_MEMBER_STATE_failed;
+}
+
 /*
  * returns true if p1 is better than p2:
  */
 static inline bool ptr_better(struct bch_fs *c,
 			      const struct extent_ptr_decoded p1,
-			      const struct extent_ptr_decoded p2)
+			      u64 p1_latency,
+			      struct bch_dev *ca1,
+			      const struct extent_ptr_decoded p2,
+			      u64 p2_latency)
 {
-	if (likely(!p1.idx && !p2.idx)) {
-		u64 l1 = dev_latency(c, p1.ptr.dev);
-		u64 l2 = dev_latency(c, p2.ptr.dev);
+	struct bch_dev *ca2 = bch2_dev_rcu(c, p2.ptr.dev);
 
-		/*
-		 * Square the latencies, to bias more in favor of the faster
-		 * device - we never want to stop issuing reads to the slower
-		 * device altogether, so that we can update our latency numbers:
-		 */
-		l1 *= l1;
-		l2 *= l2;
+	int failed_delta = dev_failed(ca1) - dev_failed(ca2);
+	if (unlikely(failed_delta))
+		return failed_delta < 0;
 
-		/* Pick at random, biased in favor of the faster device: */
+	if (unlikely(bch2_force_reconstruct_read))
+		return p1.do_ec_reconstruct > p2.do_ec_reconstruct;
 
-		return bch2_get_random_u64_below(l1 + l2) > l1;
-	}
+	if (unlikely(p1.do_ec_reconstruct || p2.do_ec_reconstruct))
+		return p1.do_ec_reconstruct < p2.do_ec_reconstruct;
 
-	if (bch2_force_reconstruct_read)
-		return p1.idx > p2.idx;
+	int crc_retry_delta = (int) p1.crc_retry_nr - (int) p2.crc_retry_nr;
+	if (unlikely(crc_retry_delta))
+		return crc_retry_delta < 0;
 
-	return p1.idx < p2.idx;
+	/* Pick at random, biased in favor of the faster device: */
+
+	return bch2_get_random_u64_below(p1_latency + p2_latency) > p1_latency;
 }
 
 /*
@@ -115,64 +127,104 @@ static inline bool ptr_better(struct bch_fs *c,
  */
 int bch2_bkey_pick_read_device(struct bch_fs *c, struct bkey_s_c k,
 			       struct bch_io_failures *failed,
-			       struct extent_ptr_decoded *pick)
+			       struct extent_ptr_decoded *pick,
+			       int dev)
 {
-	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
-	const union bch_extent_entry *entry;
-	struct extent_ptr_decoded p;
-	struct bch_dev_io_failures *f;
-	int ret = 0;
+	bool have_csum_errors = false, have_io_errors = false, have_missing_devs = false;
+	bool have_dirty_ptrs = false, have_pick = false;
 
 	if (k.k->type == KEY_TYPE_error)
 		return -BCH_ERR_key_type_error;
 
 	rcu_read_lock();
+	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+	const union bch_extent_entry *entry;
+	struct extent_ptr_decoded p;
+	u64 pick_latency;
+
 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
+		have_dirty_ptrs |= !p.ptr.cached;
+
 		/*
 		 * Unwritten extent: no need to actually read, treat it as a
 		 * hole and return 0s:
 		 */
 		if (p.ptr.unwritten) {
-			ret = 0;
-			break;
+			rcu_read_unlock();
+			return 0;
 		}
 
-		/*
-		 * If there are any dirty pointers it's an error if we can't
-		 * read:
-		 */
-		if (!ret && !p.ptr.cached)
-			ret = -BCH_ERR_no_device_to_read_from;
+		/* Are we being asked to read from a specific device? */
+		if (dev >= 0 && p.ptr.dev != dev)
+			continue;
 
 		struct bch_dev *ca = bch2_dev_rcu(c, p.ptr.dev);
 
 		if (p.ptr.cached && (!ca || dev_ptr_stale_rcu(ca, &p.ptr)))
 			continue;
 
-		f = failed ? bch2_dev_io_failures(failed, p.ptr.dev) : NULL;
-		if (f)
-			p.idx = f->nr_failed < f->nr_retries
-				? f->idx
-				: f->idx + 1;
+		struct bch_dev_io_failures *f =
+			unlikely(failed) ? bch2_dev_io_failures(failed, p.ptr.dev) : NULL;
+		if (unlikely(f)) {
+			p.crc_retry_nr	   = f->failed_csum_nr;
+			p.has_ec	  &= ~f->failed_ec;
 
-		if (!p.idx && (!ca || !bch2_dev_is_readable(ca)))
-			p.idx++;
+			if (ca && ca->mi.state != BCH_MEMBER_STATE_failed) {
+				have_io_errors	|= f->failed_io;
+				have_io_errors	|= f->failed_ec;
+			}
+			have_csum_errors	|= !!f->failed_csum_nr;
 
-		if (!p.idx && p.has_ec && bch2_force_reconstruct_read)
-			p.idx++;
+			if (p.has_ec && (f->failed_io || f->failed_csum_nr))
+				p.do_ec_reconstruct = true;
+			else if (f->failed_io ||
+				 f->failed_csum_nr > c->opts.checksum_err_retry_nr)
+				continue;
+		}
 
-		if (p.idx > (unsigned) p.has_ec)
-			continue;
+		have_missing_devs |= ca && !bch2_dev_is_online(ca);
 
-		if (ret > 0 && !ptr_better(c, p, *pick))
-			continue;
+		if (!ca || !bch2_dev_is_online(ca)) {
+			if (!p.has_ec)
+				continue;
+			p.do_ec_reconstruct = true;
+		}
+
+		if (bch2_force_reconstruct_read && p.has_ec)
+			p.do_ec_reconstruct = true;
 
-		*pick = p;
-		ret = 1;
+		u64 p_latency = dev_latency(ca);
+		/*
+		 * Square the latencies, to bias more in favor of the faster
+		 * device - we never want to stop issuing reads to the slower
+		 * device altogether, so that we can update our latency numbers:
+		 */
+		p_latency *= p_latency;
+
+		if (!have_pick ||
+		    ptr_better(c,
+			       p, p_latency, ca,
+			       *pick, pick_latency)) {
+			*pick = p;
+			pick_latency = p_latency;
+			have_pick = true;
+		}
 	}
 	rcu_read_unlock();
 
-	return ret;
+	if (have_pick)
+		return 1;
+	if (!have_dirty_ptrs)
+		return 0;
+	if (have_missing_devs)
+		return -BCH_ERR_no_device_to_read_from;
+	if (have_csum_errors)
+		return -BCH_ERR_data_read_csum_err;
+	if (have_io_errors)
+		return -BCH_ERR_data_read_io_err;
+
+	WARN_ONCE(1, "unhandled error case in %s\n", __func__);
+	return -EINVAL;
 }
 
 /* KEY_TYPE_btree_ptr: */
@@ -536,29 +588,35 @@ static void bch2_extent_crc_pack(union bch_extent_crc *dst,
 				 struct bch_extent_crc_unpacked src,
 				 enum bch_extent_entry_type type)
 {
-#define set_common_fields(_dst, _src)					\
-		_dst.type		= 1 << type;			\
-		_dst.csum_type		= _src.csum_type,		\
-		_dst.compression_type	= _src.compression_type,	\
-		_dst._compressed_size	= _src.compressed_size - 1,	\
-		_dst._uncompressed_size	= _src.uncompressed_size - 1,	\
-		_dst.offset		= _src.offset
+#define common_fields(_src)						\
+		.type			= BIT(type),			\
+		.csum_type		= _src.csum_type,		\
+		.compression_type	= _src.compression_type,	\
+		._compressed_size	= _src.compressed_size - 1,	\
+		._uncompressed_size	= _src.uncompressed_size - 1,	\
+		.offset			= _src.offset
 
 	switch (type) {
 	case BCH_EXTENT_ENTRY_crc32:
-		set_common_fields(dst->crc32, src);
-		dst->crc32.csum		= (u32 __force) *((__le32 *) &src.csum.lo);
+		dst->crc32		= (struct bch_extent_crc32) {
+			common_fields(src),
+			.csum		= (u32 __force) *((__le32 *) &src.csum.lo),
+		};
 		break;
 	case BCH_EXTENT_ENTRY_crc64:
-		set_common_fields(dst->crc64, src);
-		dst->crc64.nonce	= src.nonce;
-		dst->crc64.csum_lo	= (u64 __force) src.csum.lo;
-		dst->crc64.csum_hi	= (u64 __force) *((__le16 *) &src.csum.hi);
+		dst->crc64		= (struct bch_extent_crc64) {
+			common_fields(src),
+			.nonce		= src.nonce,
+			.csum_lo	= (u64 __force) src.csum.lo,
+			.csum_hi	= (u64 __force) *((__le16 *) &src.csum.hi),
+		};
 		break;
 	case BCH_EXTENT_ENTRY_crc128:
-		set_common_fields(dst->crc128, src);
-		dst->crc128.nonce	= src.nonce;
-		dst->crc128.csum	= src.csum;
+		dst->crc128		= (struct bch_extent_crc128) {
+			common_fields(src),
+			.nonce		= src.nonce,
+			.csum		= src.csum,
+		};
 		break;
 	default:
 		BUG();
@@ -997,7 +1055,7 @@ static bool want_cached_ptr(struct bch_fs *c, struct bch_io_opts *opts,
 
 	struct bch_dev *ca = bch2_dev_rcu_noerror(c, ptr->dev);
 
-	return ca && bch2_dev_is_readable(ca) && !dev_ptr_stale_rcu(ca, ptr);
+	return ca && bch2_dev_is_healthy(ca) && !dev_ptr_stale_rcu(ca, ptr);
 }
 
 void bch2_extent_ptr_set_cached(struct bch_fs *c,
@@ -1220,6 +1278,10 @@ void bch2_bkey_ptrs_to_text(struct printbuf *out, struct bch_fs *c,
 			bch2_extent_rebalance_to_text(out, c, &entry->rebalance);
 			break;
 
+		case BCH_EXTENT_ENTRY_flags:
+			prt_bitflags(out, bch2_extent_flags_strs, entry->flags.flags);
+			break;
+
 		default:
 			prt_printf(out, "(invalid extent entry %.16llx)", *((u64 *) entry));
 			return;
@@ -1381,6 +1443,11 @@ int bch2_bkey_ptrs_validate(struct bch_fs *c, struct bkey_s_c k,
 #endif
 			break;
 		}
+		case BCH_EXTENT_ENTRY_flags:
+			bkey_fsck_err_on(entry != ptrs.start,
+					 c, extent_flags_not_at_start,
+					 "extent flags entry not at start");
+			break;
 		}
 	}
 
@@ -1447,6 +1514,28 @@ void bch2_ptr_swab(struct bkey_s k)
 	}
 }
 
+int bch2_bkey_extent_flags_set(struct bch_fs *c, struct bkey_i *k, u64 flags)
+{
+	int ret = bch2_request_incompat_feature(c, bcachefs_metadata_version_extent_flags);
+	if (ret)
+		return ret;
+
+	struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
+
+	if (ptrs.start != ptrs.end &&
+	    extent_entry_type(ptrs.start) == BCH_EXTENT_ENTRY_flags) {
+		ptrs.start->flags.flags = flags;
+	} else {
+		struct bch_extent_flags f = {
+			.type	= BIT(BCH_EXTENT_ENTRY_flags),
+			.flags	= flags,
+		};
+		__extent_entry_insert(k, ptrs.start, (union bch_extent_entry *) &f);
+	}
+
+	return 0;
+}
+
 /* Generic extent code: */
 
 int bch2_cut_front_s(struct bpos where, struct bkey_s k)
@@ -1492,8 +1581,8 @@ int bch2_cut_front_s(struct bpos where, struct bkey_s k)
 				entry->crc128.offset += sub;
 				break;
 			case BCH_EXTENT_ENTRY_stripe_ptr:
-				break;
 			case BCH_EXTENT_ENTRY_rebalance:
+			case BCH_EXTENT_ENTRY_flags:
 				break;
 			}
 
diff --git a/fs/bcachefs/extents.h b/fs/bcachefs/extents.h
index 204d765dd74c..e78a39e7e18f 100644
--- a/fs/bcachefs/extents.h
+++ b/fs/bcachefs/extents.h
@@ -320,8 +320,9 @@ static inline struct bkey_ptrs bch2_bkey_ptrs(struct bkey_s k)
 ({									\
 	__label__ out;							\
 									\
-	(_ptr).idx	= 0;						\
-	(_ptr).has_ec	= false;					\
+	(_ptr).has_ec			= false;			\
+	(_ptr).do_ec_reconstruct	= false;			\
+	(_ptr).crc_retry_nr		= 0;				\
 									\
 	__bkey_extent_entry_for_each_from(_entry, _end, _entry)		\
 		switch (__extent_entry_type(_entry)) {			\
@@ -401,10 +402,10 @@ out:									\
 struct bch_dev_io_failures *bch2_dev_io_failures(struct bch_io_failures *,
 						 unsigned);
 void bch2_mark_io_failure(struct bch_io_failures *,
-			  struct extent_ptr_decoded *);
+			  struct extent_ptr_decoded *, bool);
 int bch2_bkey_pick_read_device(struct bch_fs *, struct bkey_s_c,
 			       struct bch_io_failures *,
-			       struct extent_ptr_decoded *);
+			       struct extent_ptr_decoded *, int);
 
 /* KEY_TYPE_btree_ptr: */
 
@@ -753,4 +754,19 @@ static inline void bch2_key_resize(struct bkey *k, unsigned new_size)
 	k->size = new_size;
 }
 
+static inline u64 bch2_bkey_extent_ptrs_flags(struct bkey_ptrs_c ptrs)
+{
+	if (ptrs.start != ptrs.end &&
+	    extent_entry_type(ptrs.start) == BCH_EXTENT_ENTRY_flags)
+		return ptrs.start->flags.flags;
+	return 0;
+}
+
+static inline u64 bch2_bkey_extent_flags(struct bkey_s_c k)
+{
+	return bch2_bkey_extent_ptrs_flags(bch2_bkey_ptrs_c(k));
+}
+
+int bch2_bkey_extent_flags_set(struct bch_fs *, struct bkey_i *, u64);
+
 #endif /* _BCACHEFS_EXTENTS_H */
diff --git a/fs/bcachefs/extents_format.h b/fs/bcachefs/extents_format.h
index c198dfc376d6..74c0252cbd98 100644
--- a/fs/bcachefs/extents_format.h
+++ b/fs/bcachefs/extents_format.h
@@ -79,8 +79,9 @@
 	x(crc64,		2)		\
 	x(crc128,		3)		\
 	x(stripe_ptr,		4)		\
-	x(rebalance,		5)
-#define BCH_EXTENT_ENTRY_MAX	6
+	x(rebalance,		5)		\
+	x(flags,		6)
+#define BCH_EXTENT_ENTRY_MAX	7
 
 enum bch_extent_entry_type {
 #define x(f, n) BCH_EXTENT_ENTRY_##f = n,
@@ -201,6 +202,25 @@ struct bch_extent_stripe_ptr {
 #endif
 };
 
+#define BCH_EXTENT_FLAGS()		\
+	x(poisoned,		0)
+
+enum bch_extent_flags_e {
+#define x(n, v)	BCH_EXTENT_FLAG_##n = v,
+	BCH_EXTENT_FLAGS()
+#undef x
+};
+
+struct bch_extent_flags {
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+	__u64			type:7,
+				flags:57;
+#elif defined (__BIG_ENDIAN_BITFIELD)
+	__u64			flags:57,
+				type:7;
+#endif
+};
+
 /* bch_extent_rebalance: */
 #include "rebalance_format.h"
 
diff --git a/fs/bcachefs/extents_types.h b/fs/bcachefs/extents_types.h
index 43d6c341ecca..e51529dca4c2 100644
--- a/fs/bcachefs/extents_types.h
+++ b/fs/bcachefs/extents_types.h
@@ -20,8 +20,9 @@ struct bch_extent_crc_unpacked {
 };
 
 struct extent_ptr_decoded {
-	unsigned			idx;
 	bool				has_ec;
+	bool				do_ec_reconstruct;
+	u8				crc_retry_nr;
 	struct bch_extent_crc_unpacked	crc;
 	struct bch_extent_ptr		ptr;
 	struct bch_extent_stripe_ptr	ec;
@@ -31,10 +32,10 @@ struct bch_io_failures {
 	u8			nr;
 	struct bch_dev_io_failures {
 		u8		dev;
-		u8		idx;
-		u8		nr_failed;
-		u8		nr_retries;
-	}			devs[BCH_REPLICAS_MAX];
+		unsigned	failed_csum_nr:6,
+				failed_io:1,
+				failed_ec:1;
+	}			devs[BCH_REPLICAS_MAX + 1];
 };
 
 #endif /* _BCACHEFS_EXTENTS_TYPES_H */
diff --git a/fs/bcachefs/eytzinger.c b/fs/bcachefs/eytzinger.c
index 2eaffe37b5e7..0e742555cb0a 100644
--- a/fs/bcachefs/eytzinger.c
+++ b/fs/bcachefs/eytzinger.c
@@ -148,89 +148,99 @@ static int do_cmp(const void *a, const void *b, cmp_r_func_t cmp, const void *pr
 	return cmp(a, b, priv);
 }
 
-static inline int eytzinger0_do_cmp(void *base, size_t n, size_t size,
+static inline int eytzinger1_do_cmp(void *base1, size_t n, size_t size,
 			 cmp_r_func_t cmp_func, const void *priv,
 			 size_t l, size_t r)
 {
-	return do_cmp(base + inorder_to_eytzinger0(l, n) * size,
-		      base + inorder_to_eytzinger0(r, n) * size,
+	return do_cmp(base1 + inorder_to_eytzinger1(l, n) * size,
+		      base1 + inorder_to_eytzinger1(r, n) * size,
 		      cmp_func, priv);
 }
 
-static inline void eytzinger0_do_swap(void *base, size_t n, size_t size,
+static inline void eytzinger1_do_swap(void *base1, size_t n, size_t size,
 			   swap_r_func_t swap_func, const void *priv,
 			   size_t l, size_t r)
 {
-	do_swap(base + inorder_to_eytzinger0(l, n) * size,
-		base + inorder_to_eytzinger0(r, n) * size,
+	do_swap(base1 + inorder_to_eytzinger1(l, n) * size,
+		base1 + inorder_to_eytzinger1(r, n) * size,
 		size, swap_func, priv);
 }
 
-void eytzinger0_sort_r(void *base, size_t n, size_t size,
-		       cmp_r_func_t cmp_func,
-		       swap_r_func_t swap_func,
-		       const void *priv)
+static void eytzinger1_sort_r(void *base1, size_t n, size_t size,
+			      cmp_r_func_t cmp_func,
+			      swap_r_func_t swap_func,
+			      const void *priv)
 {
-	int i, j, k;
+	unsigned i, j, k;
 
 	/* called from 'sort' without swap function, let's pick the default */
 	if (swap_func == SWAP_WRAPPER && !((struct wrapper *)priv)->swap_func)
 		swap_func = NULL;
 
 	if (!swap_func) {
-		if (is_aligned(base, size, 8))
+		if (is_aligned(base1, size, 8))
 			swap_func = SWAP_WORDS_64;
-		else if (is_aligned(base, size, 4))
+		else if (is_aligned(base1, size, 4))
 			swap_func = SWAP_WORDS_32;
 		else
 			swap_func = SWAP_BYTES;
 	}
 
 	/* heapify */
-	for (i = n / 2 - 1; i >= 0; --i) {
+	for (i = n / 2; i >= 1; --i) {
 		/* Find the sift-down path all the way to the leaves. */
-		for (j = i; k = j * 2 + 1, k + 1 < n;)
-			j = eytzinger0_do_cmp(base, n, size, cmp_func, priv, k, k + 1) > 0 ? k : k + 1;
+		for (j = i; k = j * 2, k < n;)
+			j = eytzinger1_do_cmp(base1, n, size, cmp_func, priv, k, k + 1) > 0 ? k : k + 1;
 
 		/* Special case for the last leaf with no sibling. */
-		if (j * 2 + 2 == n)
-			j = j * 2 + 1;
+		if (j * 2 == n)
+			j *= 2;
 
 		/* Backtrack to the correct location. */
-		while (j != i && eytzinger0_do_cmp(base, n, size, cmp_func, priv, i, j) >= 0)
-			j = (j - 1) / 2;
+		while (j != i && eytzinger1_do_cmp(base1, n, size, cmp_func, priv, i, j) >= 0)
+			j /= 2;
 
 		/* Shift the element into its correct place. */
 		for (k = j; j != i;) {
-			j = (j - 1) / 2;
-			eytzinger0_do_swap(base, n, size, swap_func, priv, j, k);
+			j /= 2;
+			eytzinger1_do_swap(base1, n, size, swap_func, priv, j, k);
 		}
 	}
 
 	/* sort */
-	for (i = n - 1; i > 0; --i) {
-		eytzinger0_do_swap(base, n, size, swap_func, priv, 0, i);
+	for (i = n; i > 1; --i) {
+		eytzinger1_do_swap(base1, n, size, swap_func, priv, 1, i);
 
 		/* Find the sift-down path all the way to the leaves. */
-		for (j = 0; k = j * 2 + 1, k + 1 < i;)
-			j = eytzinger0_do_cmp(base, n, size, cmp_func, priv, k, k + 1) > 0 ? k : k + 1;
+		for (j = 1; k = j * 2, k + 1 < i;)
+			j = eytzinger1_do_cmp(base1, n, size, cmp_func, priv, k, k + 1) > 0 ? k : k + 1;
 
 		/* Special case for the last leaf with no sibling. */
-		if (j * 2 + 2 == i)
-			j = j * 2 + 1;
+		if (j * 2 + 1 == i)
+			j *= 2;
 
 		/* Backtrack to the correct location. */
-		while (j && eytzinger0_do_cmp(base, n, size, cmp_func, priv, 0, j) >= 0)
-			j = (j - 1) / 2;
+		while (j >= 1 && eytzinger1_do_cmp(base1, n, size, cmp_func, priv, 1, j) >= 0)
+			j /= 2;
 
 		/* Shift the element into its correct place. */
-		for (k = j; j;) {
-			j = (j - 1) / 2;
-			eytzinger0_do_swap(base, n, size, swap_func, priv, j, k);
+		for (k = j; j > 1;) {
+			j /= 2;
+			eytzinger1_do_swap(base1, n, size, swap_func, priv, j, k);
 		}
 	}
 }
 
+void eytzinger0_sort_r(void *base, size_t n, size_t size,
+		       cmp_r_func_t cmp_func,
+		       swap_r_func_t swap_func,
+		       const void *priv)
+{
+	void *base1 = base - size;
+
+	return eytzinger1_sort_r(base1, n, size, cmp_func, swap_func, priv);
+}
+
 void eytzinger0_sort(void *base, size_t n, size_t size,
 		     cmp_func_t cmp_func,
 		     swap_func_t swap_func)
diff --git a/fs/bcachefs/eytzinger.h b/fs/bcachefs/eytzinger.h
index 0541192d7bc0..643c1f716061 100644
--- a/fs/bcachefs/eytzinger.h
+++ b/fs/bcachefs/eytzinger.h
@@ -6,6 +6,7 @@
 #include <linux/log2.h>
 
 #ifdef EYTZINGER_DEBUG
+#include <linux/bug.h>
 #define EYTZINGER_BUG_ON(cond)		BUG_ON(cond)
 #else
 #define EYTZINGER_BUG_ON(cond)
@@ -56,24 +57,14 @@ static inline unsigned eytzinger1_last(unsigned size)
 	return rounddown_pow_of_two(size + 1) - 1;
 }
 
-/*
- * eytzinger1_next() and eytzinger1_prev() have the nice properties that
- *
- * eytzinger1_next(0) == eytzinger1_first())
- * eytzinger1_prev(0) == eytzinger1_last())
- *
- * eytzinger1_prev(eytzinger1_first()) == 0
- * eytzinger1_next(eytzinger1_last()) == 0
- */
-
 static inline unsigned eytzinger1_next(unsigned i, unsigned size)
 {
-	EYTZINGER_BUG_ON(i > size);
+	EYTZINGER_BUG_ON(i == 0 || i > size);
 
 	if (eytzinger1_right_child(i) <= size) {
 		i = eytzinger1_right_child(i);
 
-		i <<= __fls(size + 1) - __fls(i);
+		i <<= __fls(size) - __fls(i);
 		i >>= i > size;
 	} else {
 		i >>= ffz(i) + 1;
@@ -84,12 +75,12 @@ static inline unsigned eytzinger1_next(unsigned i, unsigned size)
 
 static inline unsigned eytzinger1_prev(unsigned i, unsigned size)
 {
-	EYTZINGER_BUG_ON(i > size);
+	EYTZINGER_BUG_ON(i == 0 || i > size);
 
 	if (eytzinger1_left_child(i) <= size) {
 		i = eytzinger1_left_child(i) + 1;
 
-		i <<= __fls(size + 1) - __fls(i);
+		i <<= __fls(size) - __fls(i);
 		i -= 1;
 		i >>= i > size;
 	} else {
@@ -243,73 +234,63 @@ static inline unsigned inorder_to_eytzinger0(unsigned i, unsigned size)
 	     (_i) != -1;				\
 	     (_i) = eytzinger0_next((_i), (_size)))
 
+#define eytzinger0_for_each_prev(_i, _size)		\
+	for (unsigned (_i) = eytzinger0_last((_size));	\
+	     (_i) != -1;				\
+	     (_i) = eytzinger0_prev((_i), (_size)))
+
 /* return greatest node <= @search, or -1 if not found */
 static inline int eytzinger0_find_le(void *base, size_t nr, size_t size,
 				     cmp_func_t cmp, const void *search)
 {
-	unsigned i, n = 0;
-
-	if (!nr)
-		return -1;
-
-	do {
-		i = n;
-		n = eytzinger0_child(i, cmp(base + i * size, search) <= 0);
-	} while (n < nr);
-
-	if (n & 1) {
-		/*
-		 * @i was greater than @search, return previous node:
-		 *
-		 * if @i was leftmost/smallest element,
-		 * eytzinger0_prev(eytzinger0_first())) returns -1, as expected
-		 */
-		return eytzinger0_prev(i, nr);
-	} else {
-		return i;
-	}
+	void *base1 = base - size;
+	unsigned n = 1;
+
+	while (n <= nr)
+		n = eytzinger1_child(n, cmp(base1 + n * size, search) <= 0);
+	n >>= __ffs(n) + 1;
+	return n - 1;
 }
 
+/* return smallest node > @search, or -1 if not found */
 static inline int eytzinger0_find_gt(void *base, size_t nr, size_t size,
 				     cmp_func_t cmp, const void *search)
 {
-	ssize_t idx = eytzinger0_find_le(base, nr, size, cmp, search);
+	void *base1 = base - size;
+	unsigned n = 1;
 
-	/*
-	 * if eytitzinger0_find_le() returned -1 - no element was <= search - we
-	 * want to return the first element; next/prev identities mean this work
-	 * as expected
-	 *
-	 * similarly if find_le() returns last element, we should return -1;
-	 * identities mean this all works out:
-	 */
-	return eytzinger0_next(idx, nr);
+	while (n <= nr)
+		n = eytzinger1_child(n, cmp(base1 + n * size, search) <= 0);
+	n >>= __ffs(n + 1) + 1;
+	return n - 1;
 }
 
+/* return smallest node >= @search, or -1 if not found */
 static inline int eytzinger0_find_ge(void *base, size_t nr, size_t size,
 				     cmp_func_t cmp, const void *search)
 {
-	ssize_t idx = eytzinger0_find_le(base, nr, size, cmp, search);
-
-	if (idx < nr && !cmp(base + idx * size, search))
-		return idx;
+	void *base1 = base - size;
+	unsigned n = 1;
 
-	return eytzinger0_next(idx, nr);
+	while (n <= nr)
+		n = eytzinger1_child(n, cmp(base1 + n * size, search) < 0);
+	n >>= __ffs(n + 1) + 1;
+	return n - 1;
 }
 
 #define eytzinger0_find(base, nr, size, _cmp, search)			\
 ({									\
-	void *_base		= (base);				\
+	size_t _size		= (size);				\
+	void *_base1		= (void *)(base) - _size;		\
 	const void *_search	= (search);				\
 	size_t _nr		= (nr);					\
-	size_t _size		= (size);				\
-	size_t _i		= 0;					\
+	size_t _i		= 1;					\
 	int _res;							\
 									\
-	while (_i < _nr &&						\
-	       (_res = _cmp(_search, _base + _i * _size)))		\
-		_i = eytzinger0_child(_i, _res > 0);			\
-	_i;								\
+	while (_i <= _nr &&						\
+	       (_res = _cmp(_search, _base1 + _i * _size)))		\
+		_i = eytzinger1_child(_i, _res > 0);			\
+	_i - 1;								\
 })
 
 void eytzinger0_sort_r(void *, size_t, size_t,
diff --git a/fs/bcachefs/fs-io-buffered.c b/fs/bcachefs/fs-io-buffered.c
index ab1d5db2fa56..a03e2c780cba 100644
--- a/fs/bcachefs/fs-io-buffered.c
+++ b/fs/bcachefs/fs-io-buffered.c
@@ -110,11 +110,21 @@ static int readpage_bio_extend(struct btree_trans *trans,
 			if (!get_more)
 				break;
 
+			unsigned sectors_remaining = sectors_this_extent - bio_sectors(bio);
+
+			if (sectors_remaining < PAGE_SECTORS << mapping_min_folio_order(iter->mapping))
+				break;
+
+			unsigned order = ilog2(rounddown_pow_of_two(sectors_remaining) / PAGE_SECTORS);
+
+			/* ensure proper alignment */
+			order = min(order, __ffs(folio_offset|BIT(31)));
+
 			folio = xa_load(&iter->mapping->i_pages, folio_offset);
 			if (folio && !xa_is_value(folio))
 				break;
 
-			folio = filemap_alloc_folio(readahead_gfp_mask(iter->mapping), 0);
+			folio = filemap_alloc_folio(readahead_gfp_mask(iter->mapping), order);
 			if (!folio)
 				break;
 
@@ -149,12 +159,10 @@ static void bchfs_read(struct btree_trans *trans,
 	struct bch_fs *c = trans->c;
 	struct btree_iter iter;
 	struct bkey_buf sk;
-	int flags = BCH_READ_RETRY_IF_STALE|
-		BCH_READ_MAY_PROMOTE;
+	int flags = BCH_READ_retry_if_stale|
+		BCH_READ_may_promote;
 	int ret = 0;
 
-	rbio->c = c;
-	rbio->start_time = local_clock();
 	rbio->subvol = inum.subvol;
 
 	bch2_bkey_buf_init(&sk);
@@ -211,17 +219,17 @@ static void bchfs_read(struct btree_trans *trans,
 		swap(rbio->bio.bi_iter.bi_size, bytes);
 
 		if (rbio->bio.bi_iter.bi_size == bytes)
-			flags |= BCH_READ_LAST_FRAGMENT;
+			flags |= BCH_READ_last_fragment;
 
 		bch2_bio_page_state_set(&rbio->bio, k);
 
 		bch2_read_extent(trans, rbio, iter.pos,
 				 data_btree, k, offset_into_extent, flags);
+		swap(rbio->bio.bi_iter.bi_size, bytes);
 
-		if (flags & BCH_READ_LAST_FRAGMENT)
+		if (flags & BCH_READ_last_fragment)
 			break;
 
-		swap(rbio->bio.bi_iter.bi_size, bytes);
 		bio_advance(&rbio->bio, bytes);
 err:
 		if (ret &&
@@ -232,7 +240,8 @@ static void bchfs_read(struct btree_trans *trans,
 
 	if (ret) {
 		struct printbuf buf = PRINTBUF;
-		bch2_inum_offset_err_msg_trans(trans, &buf, inum, iter.pos.offset << 9);
+		lockrestart_do(trans,
+			bch2_inum_offset_err_msg_trans(trans, &buf, inum, iter.pos.offset << 9));
 		prt_printf(&buf, "read error %i from btree lookup", ret);
 		bch_err_ratelimited(c, "%s", buf.buf);
 		printbuf_exit(&buf);
@@ -280,12 +289,13 @@ void bch2_readahead(struct readahead_control *ractl)
 		struct bch_read_bio *rbio =
 			rbio_init(bio_alloc_bioset(NULL, n, REQ_OP_READ,
 						   GFP_KERNEL, &c->bio_read),
-				  opts);
+				  c,
+				  opts,
+				  bch2_readpages_end_io);
 
 		readpage_iter_advance(&readpages_iter);
 
 		rbio->bio.bi_iter.bi_sector = folio_sector(folio);
-		rbio->bio.bi_end_io = bch2_readpages_end_io;
 		BUG_ON(!bio_add_folio(&rbio->bio, folio, folio_size(folio), 0));
 
 		bchfs_read(trans, rbio, inode_inum(inode),
@@ -323,10 +333,10 @@ int bch2_read_single_folio(struct folio *folio, struct address_space *mapping)
 	bch2_inode_opts_get(&opts, c, &inode->ei_inode);
 
 	rbio = rbio_init(bio_alloc_bioset(NULL, 1, REQ_OP_READ, GFP_KERNEL, &c->bio_read),
-			 opts);
+			 c,
+			 opts,
+			 bch2_read_single_folio_end_io);
 	rbio->bio.bi_private = &done;
-	rbio->bio.bi_end_io = bch2_read_single_folio_end_io;
-
 	rbio->bio.bi_opf = REQ_OP_READ|REQ_SYNC;
 	rbio->bio.bi_iter.bi_sector = folio_sector(folio);
 	BUG_ON(!bio_add_folio(&rbio->bio, folio, folio_size(folio), 0));
@@ -420,7 +430,7 @@ static void bch2_writepage_io_done(struct bch_write_op *op)
 		}
 	}
 
-	if (io->op.flags & BCH_WRITE_WROTE_DATA_INLINE) {
+	if (io->op.flags & BCH_WRITE_wrote_data_inline) {
 		bio_for_each_folio_all(fi, bio) {
 			struct bch_folio *s;
 
diff --git a/fs/bcachefs/fs-io-direct.c b/fs/bcachefs/fs-io-direct.c
index 2089c36b5866..535bc5fcbcc0 100644
--- a/fs/bcachefs/fs-io-direct.c
+++ b/fs/bcachefs/fs-io-direct.c
@@ -73,6 +73,7 @@ static int bch2_direct_IO_read(struct kiocb *req, struct iov_iter *iter)
 	struct blk_plug plug;
 	loff_t offset = req->ki_pos;
 	bool sync = is_sync_kiocb(req);
+	bool split = false;
 	size_t shorten;
 	ssize_t ret;
 
@@ -99,8 +100,6 @@ static int bch2_direct_IO_read(struct kiocb *req, struct iov_iter *iter)
 			       GFP_KERNEL,
 			       &c->dio_read_bioset);
 
-	bio->bi_end_io = bch2_direct_IO_read_endio;
-
 	dio = container_of(bio, struct dio_read, rbio.bio);
 	closure_init(&dio->cl, NULL);
 
@@ -133,12 +132,13 @@ static int bch2_direct_IO_read(struct kiocb *req, struct iov_iter *iter)
 
 	goto start;
 	while (iter->count) {
+		split = true;
+
 		bio = bio_alloc_bioset(NULL,
 				       bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS),
 				       REQ_OP_READ,
 				       GFP_KERNEL,
 				       &c->bio_read);
-		bio->bi_end_io		= bch2_direct_IO_read_split_endio;
 start:
 		bio->bi_opf		= REQ_OP_READ|REQ_SYNC;
 		bio->bi_iter.bi_sector	= offset >> 9;
@@ -160,7 +160,15 @@ static int bch2_direct_IO_read(struct kiocb *req, struct iov_iter *iter)
 		if (iter->count)
 			closure_get(&dio->cl);
 
-		bch2_read(c, rbio_init(bio, opts), inode_inum(inode));
+		struct bch_read_bio *rbio =
+			rbio_init(bio,
+				  c,
+				  opts,
+				  split
+				  ? bch2_direct_IO_read_split_endio
+				  : bch2_direct_IO_read_endio);
+
+		bch2_read(c, rbio, inode_inum(inode));
 	}
 
 	blk_finish_plug(&plug);
@@ -511,8 +519,8 @@ static __always_inline long bch2_dio_write_loop(struct dio_write *dio)
 		dio->op.devs_need_flush	= &inode->ei_devs_need_flush;
 
 		if (sync)
-			dio->op.flags |= BCH_WRITE_SYNC;
-		dio->op.flags |= BCH_WRITE_CHECK_ENOSPC;
+			dio->op.flags |= BCH_WRITE_sync;
+		dio->op.flags |= BCH_WRITE_check_enospc;
 
 		ret = bch2_quota_reservation_add(c, inode, &dio->quota_res,
 						 bio_sectors(bio), true);
diff --git a/fs/bcachefs/fs-ioctl.c b/fs/bcachefs/fs-ioctl.c
index 15725b4ce393..e3a3230fc652 100644
--- a/fs/bcachefs/fs-ioctl.c
+++ b/fs/bcachefs/fs-ioctl.c
@@ -5,8 +5,8 @@
 #include "chardev.h"
 #include "dirent.h"
 #include "fs.h"
-#include "fs-common.h"
 #include "fs-ioctl.h"
+#include "namei.h"
 #include "quota.h"
 
 #include <linux/compat.h>
@@ -54,6 +54,32 @@ static int bch2_inode_flags_set(struct btree_trans *trans,
 	    (newflags & (BCH_INODE_nodump|BCH_INODE_noatime)) != newflags)
 		return -EINVAL;
 
+	if ((newflags ^ oldflags) & BCH_INODE_casefolded) {
+#ifdef CONFIG_UNICODE
+		int ret = 0;
+		/* Not supported on individual files. */
+		if (!S_ISDIR(bi->bi_mode))
+			return -EOPNOTSUPP;
+
+		/*
+		 * Make sure the dir is empty, as otherwise we'd need to
+		 * rehash everything and update the dirent keys.
+		 */
+		ret = bch2_empty_dir_trans(trans, inode_inum(inode));
+		if (ret < 0)
+			return ret;
+
+		ret = bch2_request_incompat_feature(c,bcachefs_metadata_version_casefolding);
+		if (ret)
+			return ret;
+
+		bch2_check_set_feature(c, BCH_FEATURE_casefolding);
+#else
+		printk(KERN_ERR "Cannot use casefolding on a kernel without CONFIG_UNICODE\n");
+		return -EOPNOTSUPP;
+#endif
+	}
+
 	if (s->set_projinherit) {
 		bi->bi_fields_set &= ~(1 << Inode_opt_project);
 		bi->bi_fields_set |= ((int) s->projinherit << Inode_opt_project);
@@ -218,7 +244,7 @@ static int bch2_ioc_reinherit_attrs(struct bch_fs *c,
 	int ret = 0;
 	subvol_inum inum;
 
-	kname = kmalloc(BCH_NAME_MAX + 1, GFP_KERNEL);
+	kname = kmalloc(BCH_NAME_MAX, GFP_KERNEL);
 	if (!kname)
 		return -ENOMEM;
 
diff --git a/fs/bcachefs/fs-ioctl.h b/fs/bcachefs/fs-ioctl.h
index d30f9bb056fd..ecd3bfdcde21 100644
--- a/fs/bcachefs/fs-ioctl.h
+++ b/fs/bcachefs/fs-ioctl.h
@@ -6,19 +6,21 @@
 
 /* bcachefs inode flags -> vfs inode flags: */
 static const __maybe_unused unsigned bch_flags_to_vfs[] = {
-	[__BCH_INODE_sync]	= S_SYNC,
-	[__BCH_INODE_immutable]	= S_IMMUTABLE,
-	[__BCH_INODE_append]	= S_APPEND,
-	[__BCH_INODE_noatime]	= S_NOATIME,
+	[__BCH_INODE_sync]		= S_SYNC,
+	[__BCH_INODE_immutable]		= S_IMMUTABLE,
+	[__BCH_INODE_append]		= S_APPEND,
+	[__BCH_INODE_noatime]		= S_NOATIME,
+	[__BCH_INODE_casefolded]	= S_CASEFOLD,
 };
 
 /* bcachefs inode flags -> FS_IOC_GETFLAGS: */
 static const __maybe_unused unsigned bch_flags_to_uflags[] = {
-	[__BCH_INODE_sync]	= FS_SYNC_FL,
-	[__BCH_INODE_immutable]	= FS_IMMUTABLE_FL,
-	[__BCH_INODE_append]	= FS_APPEND_FL,
-	[__BCH_INODE_nodump]	= FS_NODUMP_FL,
-	[__BCH_INODE_noatime]	= FS_NOATIME_FL,
+	[__BCH_INODE_sync]		= FS_SYNC_FL,
+	[__BCH_INODE_immutable]		= FS_IMMUTABLE_FL,
+	[__BCH_INODE_append]		= FS_APPEND_FL,
+	[__BCH_INODE_nodump]		= FS_NODUMP_FL,
+	[__BCH_INODE_noatime]		= FS_NOATIME_FL,
+	[__BCH_INODE_casefolded]	= FS_CASEFOLD_FL,
 };
 
 /* bcachefs inode flags -> FS_IOC_FSGETXATTR: */
diff --git a/fs/bcachefs/fs.c b/fs/bcachefs/fs.c
index 90ade8f648d9..fbca200f7636 100644
--- a/fs/bcachefs/fs.c
+++ b/fs/bcachefs/fs.c
@@ -11,7 +11,6 @@
 #include "errcode.h"
 #include "extents.h"
 #include "fs.h"
-#include "fs-common.h"
 #include "fs-io.h"
 #include "fs-ioctl.h"
 #include "fs-io-buffered.h"
@@ -22,6 +21,7 @@
 #include "io_read.h"
 #include "journal.h"
 #include "keylist.h"
+#include "namei.h"
 #include "quota.h"
 #include "rebalance.h"
 #include "snapshot.h"
@@ -641,7 +641,9 @@ static struct bch_inode_info *bch2_lookup_trans(struct btree_trans *trans,
 	if (ret)
 		return ERR_PTR(ret);
 
-	ret = bch2_dirent_read_target(trans, dir, bkey_s_c_to_dirent(k), &inum);
+	struct bkey_s_c_dirent d = bkey_s_c_to_dirent(k);
+
+	ret = bch2_dirent_read_target(trans, dir, d, &inum);
 	if (ret > 0)
 		ret = -ENOENT;
 	if (ret)
@@ -651,30 +653,30 @@ static struct bch_inode_info *bch2_lookup_trans(struct btree_trans *trans,
 	if (inode)
 		goto out;
 
+	/*
+	 * Note: if check/repair needs it, we commit before
+	 * bch2_inode_hash_init_insert(), as after that point we can't take a
+	 * restart - not in the top level loop with a commit_do(), like we
+	 * usually do:
+	 */
+
 	struct bch_subvolume subvol;
 	struct bch_inode_unpacked inode_u;
 	ret =   bch2_subvolume_get(trans, inum.subvol, true, &subvol) ?:
 		bch2_inode_find_by_inum_nowarn_trans(trans, inum, &inode_u) ?:
+		bch2_check_dirent_target(trans, &dirent_iter, d, &inode_u, false) ?:
+		bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc) ?:
 		PTR_ERR_OR_ZERO(inode = bch2_inode_hash_init_insert(trans, inum, &inode_u, &subvol));
 
+	/*
+	 * don't remove it: check_inodes might find another inode that points
+	 * back to this dirent
+	 */
 	bch2_fs_inconsistent_on(bch2_err_matches(ret, ENOENT),
 				c, "dirent to missing inode:\n  %s",
-				(bch2_bkey_val_to_text(&buf, c, k), buf.buf));
+				(bch2_bkey_val_to_text(&buf, c, d.s_c), buf.buf));
 	if (ret)
 		goto err;
-
-	/* regular files may have hardlinks: */
-	if (bch2_fs_inconsistent_on(bch2_inode_should_have_single_bp(&inode_u) &&
-				    !bkey_eq(k.k->p, POS(inode_u.bi_dir, inode_u.bi_dir_offset)),
-				    c,
-				    "dirent points to inode that does not point back:\n  %s",
-				    (bch2_bkey_val_to_text(&buf, c, k),
-				     prt_printf(&buf, "\n  "),
-				     bch2_inode_unpacked_to_text(&buf, &inode_u),
-				     buf.buf))) {
-		ret = -ENOENT;
-		goto err;
-	}
 out:
 	bch2_trans_iter_exit(trans, &dirent_iter);
 	printbuf_exit(&buf);
@@ -698,6 +700,23 @@ static struct dentry *bch2_lookup(struct inode *vdir, struct dentry *dentry,
 	if (IS_ERR(inode))
 		inode = NULL;
 
+#ifdef CONFIG_UNICODE
+	if (!inode && IS_CASEFOLDED(vdir)) {
+		/*
+		 * Do not cache a negative dentry in casefolded directories
+		 * as it would need to be invalidated in the following situation:
+		 * - Lookup file "blAH" in a casefolded directory
+		 * - Creation of file "BLAH" in a casefolded directory
+		 * - Lookup file "blAH" in a casefolded directory
+		 * which would fail if we had a negative dentry.
+		 *
+		 * We should come back to this when VFS has a method to handle
+		 * this edgecase.
+		 */
+		return NULL;
+	}
+#endif
+
 	return d_splice_alias(&inode->v, dentry);
 }
 
@@ -1802,7 +1821,8 @@ static void bch2_vfs_inode_init(struct btree_trans *trans,
 		break;
 	}
 
-	mapping_set_large_folios(inode->v.i_mapping);
+	mapping_set_folio_min_order(inode->v.i_mapping,
+				    get_order(trans->c->opts.block_size));
 }
 
 static void bch2_free_inode(struct inode *vinode)
@@ -2008,44 +2028,6 @@ static struct bch_fs *bch2_path_to_fs(const char *path)
 	return c ?: ERR_PTR(-ENOENT);
 }
 
-static int bch2_remount(struct super_block *sb, int *flags,
-			struct bch_opts opts)
-{
-	struct bch_fs *c = sb->s_fs_info;
-	int ret = 0;
-
-	opt_set(opts, read_only, (*flags & SB_RDONLY) != 0);
-
-	if (opts.read_only != c->opts.read_only) {
-		down_write(&c->state_lock);
-
-		if (opts.read_only) {
-			bch2_fs_read_only(c);
-
-			sb->s_flags |= SB_RDONLY;
-		} else {
-			ret = bch2_fs_read_write(c);
-			if (ret) {
-				bch_err(c, "error going rw: %i", ret);
-				up_write(&c->state_lock);
-				ret = -EINVAL;
-				goto err;
-			}
-
-			sb->s_flags &= ~SB_RDONLY;
-		}
-
-		c->opts.read_only = opts.read_only;
-
-		up_write(&c->state_lock);
-	}
-
-	if (opt_defined(opts, errors))
-		c->opts.errors = opts.errors;
-err:
-	return bch2_err_class(ret);
-}
-
 static int bch2_show_devname(struct seq_file *seq, struct dentry *root)
 {
 	struct bch_fs *c = root->d_sb->s_fs_info;
@@ -2192,6 +2174,9 @@ static int bch2_fs_get_tree(struct fs_context *fc)
 	if (ret)
 		goto err;
 
+	if (opt_defined(opts, discard))
+		set_bit(BCH_FS_discard_mount_opt_set, &c->flags);
+
 	/* Some options can't be parsed until after the fs is started: */
 	opts = bch2_opts_empty();
 	ret = bch2_parse_mount_opts(c, &opts, NULL, opts_parse->parse_later.buf);
@@ -2200,9 +2185,10 @@ static int bch2_fs_get_tree(struct fs_context *fc)
 
 	bch2_opts_apply(&c->opts, opts);
 
-	ret = bch2_fs_start(c);
-	if (ret)
-		goto err_stop_fs;
+	/*
+	 * need to initialise sb and set c->vfs_sb _before_ starting fs,
+	 * for blk_holder_ops
+	 */
 
 	sb = sget(fc->fs_type, NULL, bch2_set_super, fc->sb_flags|SB_NOSEC, c);
 	ret = PTR_ERR_OR_ZERO(sb);
@@ -2264,6 +2250,10 @@ static int bch2_fs_get_tree(struct fs_context *fc)
 
 	sb->s_shrink->seeks = 0;
 
+	ret = bch2_fs_start(c);
+	if (ret)
+		goto err_put_super;
+
 	vinode = bch2_vfs_inode_get(c, BCACHEFS_ROOT_SUBVOL_INUM);
 	ret = PTR_ERR_OR_ZERO(vinode);
 	bch_err_msg(c, ret, "mounting: error getting root inode");
@@ -2351,8 +2341,39 @@ static int bch2_fs_reconfigure(struct fs_context *fc)
 {
 	struct super_block *sb = fc->root->d_sb;
 	struct bch2_opts_parse *opts = fc->fs_private;
+	struct bch_fs *c = sb->s_fs_info;
+	int ret = 0;
+
+	opt_set(opts->opts, read_only, (fc->sb_flags & SB_RDONLY) != 0);
 
-	return bch2_remount(sb, &fc->sb_flags, opts->opts);
+	if (opts->opts.read_only != c->opts.read_only) {
+		down_write(&c->state_lock);
+
+		if (opts->opts.read_only) {
+			bch2_fs_read_only(c);
+
+			sb->s_flags |= SB_RDONLY;
+		} else {
+			ret = bch2_fs_read_write(c);
+			if (ret) {
+				bch_err(c, "error going rw: %i", ret);
+				up_write(&c->state_lock);
+				ret = -EINVAL;
+				goto err;
+			}
+
+			sb->s_flags &= ~SB_RDONLY;
+		}
+
+		c->opts.read_only = opts->opts.read_only;
+
+		up_write(&c->state_lock);
+	}
+
+	if (opt_defined(opts->opts, errors))
+		c->opts.errors = opts->opts.errors;
+err:
+	return bch2_err_class(ret);
 }
 
 static const struct fs_context_operations bch2_context_ops = {
diff --git a/fs/bcachefs/fsck.c b/fs/bcachefs/fsck.c
index 0e85131d0af8..091057023fc5 100644
--- a/fs/bcachefs/fsck.c
+++ b/fs/bcachefs/fsck.c
@@ -10,10 +10,10 @@
 #include "dirent.h"
 #include "error.h"
 #include "fs.h"
-#include "fs-common.h"
 #include "fsck.h"
 #include "inode.h"
 #include "keylist.h"
+#include "namei.h"
 #include "recovery_passes.h"
 #include "snapshot.h"
 #include "super.h"
@@ -23,13 +23,6 @@
 #include <linux/bsearch.h>
 #include <linux/dcache.h> /* struct qstr */
 
-static bool inode_points_to_dirent(struct bch_inode_unpacked *inode,
-				   struct bkey_s_c_dirent d)
-{
-	return  inode->bi_dir		== d.k->p.inode &&
-		inode->bi_dir_offset	== d.k->p.offset;
-}
-
 static int dirent_points_to_inode_nowarn(struct bkey_s_c_dirent d,
 					 struct bch_inode_unpacked *inode)
 {
@@ -116,29 +109,6 @@ static int subvol_lookup(struct btree_trans *trans, u32 subvol,
 	return ret;
 }
 
-static int lookup_first_inode(struct btree_trans *trans, u64 inode_nr,
-			      struct bch_inode_unpacked *inode)
-{
-	struct btree_iter iter;
-	struct bkey_s_c k;
-	int ret;
-
-	for_each_btree_key_norestart(trans, iter, BTREE_ID_inodes, POS(0, inode_nr),
-				     BTREE_ITER_all_snapshots, k, ret) {
-		if (k.k->p.offset != inode_nr)
-			break;
-		if (!bkey_is_inode(k.k))
-			continue;
-		ret = bch2_inode_unpack(k, inode);
-		goto found;
-	}
-	ret = -BCH_ERR_ENOENT_inode;
-found:
-	bch_err_msg(trans->c, ret, "fetching inode %llu", inode_nr);
-	bch2_trans_iter_exit(trans, &iter);
-	return ret;
-}
-
 static int lookup_inode(struct btree_trans *trans, u64 inode_nr, u32 snapshot,
 			struct bch_inode_unpacked *inode)
 {
@@ -179,32 +149,6 @@ static int lookup_dirent_in_snapshot(struct btree_trans *trans,
 	return 0;
 }
 
-static int __remove_dirent(struct btree_trans *trans, struct bpos pos)
-{
-	struct bch_fs *c = trans->c;
-	struct btree_iter iter;
-	struct bch_inode_unpacked dir_inode;
-	struct bch_hash_info dir_hash_info;
-	int ret;
-
-	ret = lookup_first_inode(trans, pos.inode, &dir_inode);
-	if (ret)
-		goto err;
-
-	dir_hash_info = bch2_hash_info_init(c, &dir_inode);
-
-	bch2_trans_iter_init(trans, &iter, BTREE_ID_dirents, pos, BTREE_ITER_intent);
-
-	ret =   bch2_btree_iter_traverse(&iter) ?:
-		bch2_hash_delete_at(trans, bch2_dirent_hash_desc,
-				    &dir_hash_info, &iter,
-				    BTREE_UPDATE_internal_snapshot_node);
-	bch2_trans_iter_exit(trans, &iter);
-err:
-	bch_err_fn(c, ret);
-	return ret;
-}
-
 /*
  * Find any subvolume associated with a tree of snapshots
  * We can't rely on master_subvol - it might have been deleted.
@@ -548,7 +492,7 @@ static int remove_backpointer(struct btree_trans *trans,
 				     SPOS(inode->bi_dir, inode->bi_dir_offset, inode->bi_snapshot));
 	int ret = bkey_err(d) ?:
 		  dirent_points_to_inode(c, d, inode) ?:
-		  __remove_dirent(trans, d.k->p);
+		  bch2_fsck_remove_dirent(trans, d.k->p);
 	bch2_trans_iter_exit(trans, &iter);
 	return ret;
 }
@@ -1985,169 +1929,6 @@ static int check_subdir_dirents_count(struct btree_trans *trans, struct inode_wa
 		trans_was_restarted(trans, restart_count);
 }
 
-noinline_for_stack
-static int check_dirent_inode_dirent(struct btree_trans *trans,
-				   struct btree_iter *iter,
-				   struct bkey_s_c_dirent d,
-				   struct bch_inode_unpacked *target)
-{
-	struct bch_fs *c = trans->c;
-	struct printbuf buf = PRINTBUF;
-	struct btree_iter bp_iter = { NULL };
-	int ret = 0;
-
-	if (inode_points_to_dirent(target, d))
-		return 0;
-
-	if (!target->bi_dir &&
-	    !target->bi_dir_offset) {
-		fsck_err_on(S_ISDIR(target->bi_mode),
-			    trans, inode_dir_missing_backpointer,
-			    "directory with missing backpointer\n%s",
-			    (printbuf_reset(&buf),
-			     bch2_bkey_val_to_text(&buf, c, d.s_c),
-			     prt_printf(&buf, "\n"),
-			     bch2_inode_unpacked_to_text(&buf, target),
-			     buf.buf));
-
-		fsck_err_on(target->bi_flags & BCH_INODE_unlinked,
-			    trans, inode_unlinked_but_has_dirent,
-			    "inode unlinked but has dirent\n%s",
-			    (printbuf_reset(&buf),
-			     bch2_bkey_val_to_text(&buf, c, d.s_c),
-			     prt_printf(&buf, "\n"),
-			     bch2_inode_unpacked_to_text(&buf, target),
-			     buf.buf));
-
-		target->bi_flags &= ~BCH_INODE_unlinked;
-		target->bi_dir		= d.k->p.inode;
-		target->bi_dir_offset	= d.k->p.offset;
-		return __bch2_fsck_write_inode(trans, target);
-	}
-
-	if (bch2_inode_should_have_single_bp(target) &&
-	    !fsck_err(trans, inode_wrong_backpointer,
-		      "dirent points to inode that does not point back:\n  %s",
-		      (bch2_bkey_val_to_text(&buf, c, d.s_c),
-		       prt_printf(&buf, "\n  "),
-		       bch2_inode_unpacked_to_text(&buf, target),
-		       buf.buf)))
-		goto err;
-
-	struct bkey_s_c_dirent bp_dirent = dirent_get_by_pos(trans, &bp_iter,
-			      SPOS(target->bi_dir, target->bi_dir_offset, target->bi_snapshot));
-	ret = bkey_err(bp_dirent);
-	if (ret && !bch2_err_matches(ret, ENOENT))
-		goto err;
-
-	bool backpointer_exists = !ret;
-	ret = 0;
-
-	if (fsck_err_on(!backpointer_exists,
-			trans, inode_wrong_backpointer,
-			"inode %llu:%u has wrong backpointer:\n"
-			"got       %llu:%llu\n"
-			"should be %llu:%llu",
-			target->bi_inum, target->bi_snapshot,
-			target->bi_dir,
-			target->bi_dir_offset,
-			d.k->p.inode,
-			d.k->p.offset)) {
-		target->bi_dir		= d.k->p.inode;
-		target->bi_dir_offset	= d.k->p.offset;
-		ret = __bch2_fsck_write_inode(trans, target);
-		goto out;
-	}
-
-	bch2_bkey_val_to_text(&buf, c, d.s_c);
-	prt_newline(&buf);
-	if (backpointer_exists)
-		bch2_bkey_val_to_text(&buf, c, bp_dirent.s_c);
-
-	if (fsck_err_on(backpointer_exists &&
-			(S_ISDIR(target->bi_mode) ||
-			 target->bi_subvol),
-			trans, inode_dir_multiple_links,
-			"%s %llu:%u with multiple links\n%s",
-			S_ISDIR(target->bi_mode) ? "directory" : "subvolume",
-			target->bi_inum, target->bi_snapshot, buf.buf)) {
-		ret = __remove_dirent(trans, d.k->p);
-		goto out;
-	}
-
-	/*
-	 * hardlinked file with nlink 0:
-	 * We're just adjusting nlink here so check_nlinks() will pick
-	 * it up, it ignores inodes with nlink 0
-	 */
-	if (fsck_err_on(backpointer_exists && !target->bi_nlink,
-			trans, inode_multiple_links_but_nlink_0,
-			"inode %llu:%u type %s has multiple links but i_nlink 0\n%s",
-			target->bi_inum, target->bi_snapshot, bch2_d_types[d.v->d_type], buf.buf)) {
-		target->bi_nlink++;
-		target->bi_flags &= ~BCH_INODE_unlinked;
-		ret = __bch2_fsck_write_inode(trans, target);
-		if (ret)
-			goto err;
-	}
-out:
-err:
-fsck_err:
-	bch2_trans_iter_exit(trans, &bp_iter);
-	printbuf_exit(&buf);
-	bch_err_fn(c, ret);
-	return ret;
-}
-
-noinline_for_stack
-static int check_dirent_target(struct btree_trans *trans,
-			       struct btree_iter *iter,
-			       struct bkey_s_c_dirent d,
-			       struct bch_inode_unpacked *target)
-{
-	struct bch_fs *c = trans->c;
-	struct bkey_i_dirent *n;
-	struct printbuf buf = PRINTBUF;
-	int ret = 0;
-
-	ret = check_dirent_inode_dirent(trans, iter, d, target);
-	if (ret)
-		goto err;
-
-	if (fsck_err_on(d.v->d_type != inode_d_type(target),
-			trans, dirent_d_type_wrong,
-			"incorrect d_type: got %s, should be %s:\n%s",
-			bch2_d_type_str(d.v->d_type),
-			bch2_d_type_str(inode_d_type(target)),
-			(printbuf_reset(&buf),
-			 bch2_bkey_val_to_text(&buf, c, d.s_c), buf.buf))) {
-		n = bch2_trans_kmalloc(trans, bkey_bytes(d.k));
-		ret = PTR_ERR_OR_ZERO(n);
-		if (ret)
-			goto err;
-
-		bkey_reassemble(&n->k_i, d.s_c);
-		n->v.d_type = inode_d_type(target);
-		if (n->v.d_type == DT_SUBVOL) {
-			n->v.d_parent_subvol = cpu_to_le32(target->bi_parent_subvol);
-			n->v.d_child_subvol = cpu_to_le32(target->bi_subvol);
-		} else {
-			n->v.d_inum = cpu_to_le64(target->bi_inum);
-		}
-
-		ret = bch2_trans_update(trans, iter, &n->k_i, 0);
-		if (ret)
-			goto err;
-
-		d = dirent_i_to_s_c(n);
-	}
-err:
-fsck_err:
-	printbuf_exit(&buf);
-	bch_err_fn(c, ret);
-	return ret;
-}
-
 /* find a subvolume that's a descendent of @snapshot: */
 static int find_snapshot_subvol(struct btree_trans *trans, u32 snapshot, u32 *subvolid)
 {
@@ -2247,7 +2028,7 @@ static int check_dirent_to_subvol(struct btree_trans *trans, struct btree_iter *
 		if (fsck_err(trans, dirent_to_missing_subvol,
 			     "dirent points to missing subvolume\n%s",
 			     (bch2_bkey_val_to_text(&buf, c, d.s_c), buf.buf)))
-			return __remove_dirent(trans, d.k->p);
+			return bch2_fsck_remove_dirent(trans, d.k->p);
 		ret = 0;
 		goto out;
 	}
@@ -2291,7 +2072,7 @@ static int check_dirent_to_subvol(struct btree_trans *trans, struct btree_iter *
 			goto err;
 	}
 
-	ret = check_dirent_target(trans, iter, d, &subvol_root);
+	ret = bch2_check_dirent_target(trans, iter, d, &subvol_root, true);
 	if (ret)
 		goto err;
 out:
@@ -2378,13 +2159,13 @@ static int check_dirent(struct btree_trans *trans, struct btree_iter *iter,
 				(printbuf_reset(&buf),
 				 bch2_bkey_val_to_text(&buf, c, k),
 				 buf.buf))) {
-			ret = __remove_dirent(trans, d.k->p);
+			ret = bch2_fsck_remove_dirent(trans, d.k->p);
 			if (ret)
 				goto err;
 		}
 
 		darray_for_each(target->inodes, i) {
-			ret = check_dirent_target(trans, iter, d, &i->inode);
+			ret = bch2_check_dirent_target(trans, iter, d, &i->inode, true);
 			if (ret)
 				goto err;
 		}
diff --git a/fs/bcachefs/inode.c b/fs/bcachefs/inode.c
index 339b80770f1d..80051073f613 100644
--- a/fs/bcachefs/inode.c
+++ b/fs/bcachefs/inode.c
@@ -731,10 +731,9 @@ int bch2_trigger_inode(struct btree_trans *trans,
 		bkey_s_to_inode_v3(new).v->bi_journal_seq = cpu_to_le64(trans->journal_res.seq);
 	}
 
-	s64 nr = bkey_is_inode(new.k) - bkey_is_inode(old.k);
-	if ((flags & (BTREE_TRIGGER_transactional|BTREE_TRIGGER_gc)) && nr) {
-		struct disk_accounting_pos acc = { .type = BCH_DISK_ACCOUNTING_nr_inodes };
-		int ret = bch2_disk_accounting_mod(trans, &acc, &nr, 1, flags & BTREE_TRIGGER_gc);
+	s64 nr[1] = { bkey_is_inode(new.k) - bkey_is_inode(old.k) };
+	if ((flags & (BTREE_TRIGGER_transactional|BTREE_TRIGGER_gc)) && nr[0]) {
+		int ret = bch2_disk_accounting_mod2(trans, flags & BTREE_TRIGGER_gc, nr, nr_inodes);
 		if (ret)
 			return ret;
 	}
@@ -868,19 +867,6 @@ void bch2_inode_init(struct bch_fs *c, struct bch_inode_unpacked *inode_u,
 			     uid, gid, mode, rdev, parent);
 }
 
-static inline u32 bkey_generation(struct bkey_s_c k)
-{
-	switch (k.k->type) {
-	case KEY_TYPE_inode:
-	case KEY_TYPE_inode_v2:
-		BUG();
-	case KEY_TYPE_inode_generation:
-		return le32_to_cpu(bkey_s_c_to_inode_generation(k).v->bi_generation);
-	default:
-		return 0;
-	}
-}
-
 static struct bkey_i_inode_alloc_cursor *
 bch2_inode_alloc_cursor_get(struct btree_trans *trans, u64 cpu, u64 *min, u64 *max)
 {
@@ -1092,7 +1078,7 @@ int bch2_inode_rm(struct bch_fs *c, subvol_inum inum)
 		bch2_fs_inconsistent(c,
 				     "inode %llu:%u not found when deleting",
 				     inum.inum, snapshot);
-		ret = -EIO;
+		ret = -BCH_ERR_ENOENT_inode;
 		goto err;
 	}
 
@@ -1256,7 +1242,7 @@ static noinline int __bch2_inode_rm_snapshot(struct btree_trans *trans, u64 inum
 		bch2_fs_inconsistent(c,
 				     "inode %llu:%u not found when deleting",
 				     inum, snapshot);
-		ret = -EIO;
+		ret = -BCH_ERR_ENOENT_inode;
 		goto err;
 	}
 
diff --git a/fs/bcachefs/inode.h b/fs/bcachefs/inode.h
index 428b9be6af34..f82cfbf460d0 100644
--- a/fs/bcachefs/inode.h
+++ b/fs/bcachefs/inode.h
@@ -277,6 +277,7 @@ static inline bool bch2_inode_should_have_single_bp(struct bch_inode_unpacked *i
 	bool inode_has_bp = inode->bi_dir || inode->bi_dir_offset;
 
 	return S_ISDIR(inode->bi_mode) ||
+		inode->bi_subvol ||
 		(!inode->bi_nlink && inode_has_bp);
 }
 
diff --git a/fs/bcachefs/inode_format.h b/fs/bcachefs/inode_format.h
index b99a5bf1a75e..117110af1e3f 100644
--- a/fs/bcachefs/inode_format.h
+++ b/fs/bcachefs/inode_format.h
@@ -137,7 +137,8 @@ enum inode_opt_id {
 	x(i_sectors_dirty,		6)	\
 	x(unlinked,			7)	\
 	x(backptr_untrusted,		8)	\
-	x(has_child_snapshot,		9)
+	x(has_child_snapshot,		9)	\
+	x(casefolded,			10)
 
 /* bits 20+ reserved for packed fields below: */
 
diff --git a/fs/bcachefs/io_misc.c b/fs/bcachefs/io_misc.c
index 5353979117b0..6b842c8d21be 100644
--- a/fs/bcachefs/io_misc.c
+++ b/fs/bcachefs/io_misc.c
@@ -115,7 +115,8 @@ int bch2_extent_fallocate(struct btree_trans *trans,
 		bch2_increment_clock(c, sectors_allocated, WRITE);
 	if (should_print_err(ret)) {
 		struct printbuf buf = PRINTBUF;
-		bch2_inum_offset_err_msg_trans(trans, &buf, inum, iter->pos.offset << 9);
+		lockrestart_do(trans,
+			bch2_inum_offset_err_msg_trans(trans, &buf, inum, iter->pos.offset << 9));
 		prt_printf(&buf, "fallocate error: %s", bch2_err_str(ret));
 		bch_err_ratelimited(c, "%s", buf.buf);
 		printbuf_exit(&buf);
diff --git a/fs/bcachefs/io_read.c b/fs/bcachefs/io_read.c
index aa91fcf51eec..a04dffa45f5f 100644
--- a/fs/bcachefs/io_read.c
+++ b/fs/bcachefs/io_read.c
@@ -25,8 +25,15 @@
 #include "subvolume.h"
 #include "trace.h"
 
+#include <linux/random.h>
 #include <linux/sched/mm.h>
 
+#ifdef CONFIG_BCACHEFS_DEBUG
+static unsigned bch2_read_corrupt_ratio;
+module_param_named(read_corrupt_ratio, bch2_read_corrupt_ratio, uint, 0644);
+MODULE_PARM_DESC(read_corrupt_ratio, "");
+#endif
+
 #ifndef CONFIG_BCACHEFS_NO_LATENCY_ACCT
 
 static bool bch2_target_congested(struct bch_fs *c, u16 target)
@@ -80,6 +87,7 @@ struct promote_op {
 	struct rhash_head	hash;
 	struct bpos		pos;
 
+	struct work_struct	work;
 	struct data_update	write;
 	struct bio_vec		bi_inline_vecs[]; /* must be last */
 };
@@ -96,6 +104,33 @@ static inline bool have_io_error(struct bch_io_failures *failed)
 	return failed && failed->nr;
 }
 
+static inline struct data_update *rbio_data_update(struct bch_read_bio *rbio)
+{
+	EBUG_ON(rbio->split);
+
+	return rbio->data_update
+		? container_of(rbio, struct data_update, rbio)
+		: NULL;
+}
+
+static bool ptr_being_rewritten(struct bch_read_bio *orig, unsigned dev)
+{
+	struct data_update *u = rbio_data_update(orig);
+	if (!u)
+		return false;
+
+	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(bkey_i_to_s_c(u->k.k));
+	unsigned i = 0;
+	bkey_for_each_ptr(ptrs, ptr) {
+		if (ptr->dev == dev &&
+		    u->data_opts.rewrite_ptrs & BIT(i))
+			return true;
+		i++;
+	}
+
+	return false;
+}
+
 static inline int should_promote(struct bch_fs *c, struct bkey_s_c k,
 				  struct bpos pos,
 				  struct bch_io_opts opts,
@@ -105,7 +140,7 @@ static inline int should_promote(struct bch_fs *c, struct bkey_s_c k,
 	if (!have_io_error(failed)) {
 		BUG_ON(!opts.promote_target);
 
-		if (!(flags & BCH_READ_MAY_PROMOTE))
+		if (!(flags & BCH_READ_may_promote))
 			return -BCH_ERR_nopromote_may_not;
 
 		if (bch2_bkey_has_target(c, k, opts.promote_target))
@@ -125,98 +160,93 @@ static inline int should_promote(struct bch_fs *c, struct bkey_s_c k,
 	return 0;
 }
 
-static void promote_free(struct bch_fs *c, struct promote_op *op)
+static noinline void promote_free(struct bch_read_bio *rbio)
 {
-	int ret;
+	struct promote_op *op = container_of(rbio, struct promote_op, write.rbio);
+	struct bch_fs *c = rbio->c;
+
+	int ret = rhashtable_remove_fast(&c->promote_table, &op->hash,
+					 bch_promote_params);
+	BUG_ON(ret);
 
 	bch2_data_update_exit(&op->write);
 
-	ret = rhashtable_remove_fast(&c->promote_table, &op->hash,
-				     bch_promote_params);
-	BUG_ON(ret);
 	bch2_write_ref_put(c, BCH_WRITE_REF_promote);
 	kfree_rcu(op, rcu);
 }
 
 static void promote_done(struct bch_write_op *wop)
 {
-	struct promote_op *op =
-		container_of(wop, struct promote_op, write.op);
-	struct bch_fs *c = op->write.op.c;
+	struct promote_op *op = container_of(wop, struct promote_op, write.op);
+	struct bch_fs *c = op->write.rbio.c;
 
-	bch2_time_stats_update(&c->times[BCH_TIME_data_promote],
-			       op->start_time);
-	promote_free(c, op);
+	bch2_time_stats_update(&c->times[BCH_TIME_data_promote], op->start_time);
+	promote_free(&op->write.rbio);
 }
 
-static void promote_start(struct promote_op *op, struct bch_read_bio *rbio)
+static void promote_start_work(struct work_struct *work)
 {
-	struct bio *bio = &op->write.op.wbio.bio;
+	struct promote_op *op = container_of(work, struct promote_op, work);
 
-	trace_and_count(op->write.op.c, read_promote, &rbio->bio);
+	bch2_data_update_read_done(&op->write);
+}
 
-	/* we now own pages: */
-	BUG_ON(!rbio->bounce);
-	BUG_ON(rbio->bio.bi_vcnt > bio->bi_max_vecs);
+static noinline void promote_start(struct bch_read_bio *rbio)
+{
+	struct promote_op *op = container_of(rbio, struct promote_op, write.rbio);
 
-	memcpy(bio->bi_io_vec, rbio->bio.bi_io_vec,
-	       sizeof(struct bio_vec) * rbio->bio.bi_vcnt);
-	swap(bio->bi_vcnt, rbio->bio.bi_vcnt);
+	trace_and_count(op->write.op.c, io_read_promote, &rbio->bio);
 
-	bch2_data_update_read_done(&op->write, rbio->pick.crc);
+	INIT_WORK(&op->work, promote_start_work);
+	queue_work(rbio->c->write_ref_wq, &op->work);
 }
 
-static struct promote_op *__promote_alloc(struct btree_trans *trans,
-					  enum btree_id btree_id,
-					  struct bkey_s_c k,
-					  struct bpos pos,
-					  struct extent_ptr_decoded *pick,
-					  struct bch_io_opts opts,
-					  unsigned sectors,
-					  struct bch_read_bio **rbio,
-					  struct bch_io_failures *failed)
+static struct bch_read_bio *__promote_alloc(struct btree_trans *trans,
+					    enum btree_id btree_id,
+					    struct bkey_s_c k,
+					    struct bpos pos,
+					    struct extent_ptr_decoded *pick,
+					    unsigned sectors,
+					    struct bch_read_bio *orig,
+					    struct bch_io_failures *failed)
 {
 	struct bch_fs *c = trans->c;
-	struct promote_op *op = NULL;
-	struct bio *bio;
-	unsigned pages = DIV_ROUND_UP(sectors, PAGE_SECTORS);
 	int ret;
 
-	if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_promote))
-		return ERR_PTR(-BCH_ERR_nopromote_no_writes);
+	struct data_update_opts update_opts = { .write_flags = BCH_WRITE_alloc_nowait };
 
-	op = kzalloc(struct_size(op, bi_inline_vecs, pages), GFP_KERNEL);
-	if (!op) {
-		ret = -BCH_ERR_nopromote_enomem;
-		goto err;
-	}
+	if (!have_io_error(failed)) {
+		update_opts.target = orig->opts.promote_target;
+		update_opts.extra_replicas = 1;
+		update_opts.write_flags |= BCH_WRITE_cached;
+		update_opts.write_flags |= BCH_WRITE_only_specified_devs;
+	} else {
+		update_opts.target = orig->opts.foreground_target;
 
-	op->start_time = local_clock();
-	op->pos = pos;
+		struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+		unsigned ptr_bit = 1;
+		bkey_for_each_ptr(ptrs, ptr) {
+			if (bch2_dev_io_failures(failed, ptr->dev) &&
+			    !ptr_being_rewritten(orig, ptr->dev))
+				update_opts.rewrite_ptrs |= ptr_bit;
+			ptr_bit <<= 1;
+		}
 
-	/*
-	 * We don't use the mempool here because extents that aren't
-	 * checksummed or compressed can be too big for the mempool:
-	 */
-	*rbio = kzalloc(sizeof(struct bch_read_bio) +
-			sizeof(struct bio_vec) * pages,
-			GFP_KERNEL);
-	if (!*rbio) {
-		ret = -BCH_ERR_nopromote_enomem;
-		goto err;
+		if (!update_opts.rewrite_ptrs)
+			return NULL;
 	}
 
-	rbio_init(&(*rbio)->bio, opts);
-	bio_init(&(*rbio)->bio, NULL, (*rbio)->bio.bi_inline_vecs, pages, 0);
+	if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_promote))
+		return ERR_PTR(-BCH_ERR_nopromote_no_writes);
 
-	if (bch2_bio_alloc_pages(&(*rbio)->bio, sectors << 9, GFP_KERNEL)) {
+	struct promote_op *op = kzalloc(sizeof(*op), GFP_KERNEL);
+	if (!op) {
 		ret = -BCH_ERR_nopromote_enomem;
-		goto err;
+		goto err_put;
 	}
 
-	(*rbio)->bounce		= true;
-	(*rbio)->split		= true;
-	(*rbio)->kmalloc	= true;
+	op->start_time = local_clock();
+	op->pos = pos;
 
 	if (rhashtable_lookup_insert_fast(&c->promote_table, &op->hash,
 					  bch_promote_params)) {
@@ -224,68 +254,54 @@ static struct promote_op *__promote_alloc(struct btree_trans *trans,
 		goto err;
 	}
 
-	bio = &op->write.op.wbio.bio;
-	bio_init(bio, NULL, bio->bi_inline_vecs, pages, 0);
-
-	struct data_update_opts update_opts = {};
-
-	if (!have_io_error(failed)) {
-		update_opts.target = opts.promote_target;
-		update_opts.extra_replicas = 1;
-		update_opts.write_flags = BCH_WRITE_ALLOC_NOWAIT|BCH_WRITE_CACHED;
-	} else {
-		update_opts.target = opts.foreground_target;
-
-		struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
-		unsigned ptr_bit = 1;
-		bkey_for_each_ptr(ptrs, ptr) {
-			if (bch2_dev_io_failures(failed, ptr->dev))
-				update_opts.rewrite_ptrs |= ptr_bit;
-			ptr_bit <<= 1;
-		}
-	}
-
 	ret = bch2_data_update_init(trans, NULL, NULL, &op->write,
 			writepoint_hashed((unsigned long) current),
-			opts,
+			&orig->opts,
 			update_opts,
 			btree_id, k);
 	/*
 	 * possible errors: -BCH_ERR_nocow_lock_blocked,
 	 * -BCH_ERR_ENOSPC_disk_reservation:
 	 */
-	if (ret) {
-		BUG_ON(rhashtable_remove_fast(&c->promote_table, &op->hash,
-					      bch_promote_params));
-		goto err;
-	}
+	if (ret)
+		goto err_remove_hash;
 
+	rbio_init_fragment(&op->write.rbio.bio, orig);
+	op->write.rbio.bounce	= true;
+	op->write.rbio.promote	= true;
 	op->write.op.end_io = promote_done;
 
-	return op;
+	return &op->write.rbio;
+err_remove_hash:
+	BUG_ON(rhashtable_remove_fast(&c->promote_table, &op->hash,
+				      bch_promote_params));
 err:
-	if (*rbio)
-		bio_free_pages(&(*rbio)->bio);
-	kfree(*rbio);
-	*rbio = NULL;
+	bio_free_pages(&op->write.op.wbio.bio);
 	/* We may have added to the rhashtable and thus need rcu freeing: */
 	kfree_rcu(op, rcu);
+err_put:
 	bch2_write_ref_put(c, BCH_WRITE_REF_promote);
 	return ERR_PTR(ret);
 }
 
 noinline
-static struct promote_op *promote_alloc(struct btree_trans *trans,
+static struct bch_read_bio *promote_alloc(struct btree_trans *trans,
 					struct bvec_iter iter,
 					struct bkey_s_c k,
 					struct extent_ptr_decoded *pick,
-					struct bch_io_opts opts,
 					unsigned flags,
-					struct bch_read_bio **rbio,
+					struct bch_read_bio *orig,
 					bool *bounce,
 					bool *read_full,
 					struct bch_io_failures *failed)
 {
+	/*
+	 * We're in the retry path, but we don't know what to repair yet, and we
+	 * don't want to do a promote here:
+	 */
+	if (failed && !failed->nr)
+		return NULL;
+
 	struct bch_fs *c = trans->c;
 	/*
 	 * if failed != NULL we're not actually doing a promote, we're
@@ -301,18 +317,21 @@ static struct promote_op *promote_alloc(struct btree_trans *trans,
 	struct bpos pos = promote_full
 		? bkey_start_pos(k.k)
 		: POS(k.k->p.inode, iter.bi_sector);
-	struct promote_op *promote;
 	int ret;
 
-	ret = should_promote(c, k, pos, opts, flags, failed);
+	ret = should_promote(c, k, pos, orig->opts, flags, failed);
 	if (ret)
 		goto nopromote;
 
-	promote = __promote_alloc(trans,
-				  k.k->type == KEY_TYPE_reflink_v
-				  ? BTREE_ID_reflink
-				  : BTREE_ID_extents,
-				  k, pos, pick, opts, sectors, rbio, failed);
+	struct bch_read_bio *promote =
+		__promote_alloc(trans,
+				k.k->type == KEY_TYPE_reflink_v
+				? BTREE_ID_reflink
+				: BTREE_ID_extents,
+				k, pos, pick, sectors, orig, failed);
+	if (!promote)
+		return NULL;
+
 	ret = PTR_ERR_OR_ZERO(promote);
 	if (ret)
 		goto nopromote;
@@ -321,7 +340,7 @@ static struct promote_op *promote_alloc(struct btree_trans *trans,
 	*read_full	= promote_full;
 	return promote;
 nopromote:
-	trace_read_nopromote(c, ret);
+	trace_io_read_nopromote(c, ret);
 	return NULL;
 }
 
@@ -330,9 +349,17 @@ static struct promote_op *promote_alloc(struct btree_trans *trans,
 static int bch2_read_err_msg_trans(struct btree_trans *trans, struct printbuf *out,
 				   struct bch_read_bio *rbio, struct bpos read_pos)
 {
-	return bch2_inum_offset_err_msg_trans(trans, out,
-		(subvol_inum) { rbio->subvol, read_pos.inode },
-		read_pos.offset << 9);
+	int ret = lockrestart_do(trans,
+		bch2_inum_offset_err_msg_trans(trans, out,
+				(subvol_inum) { rbio->subvol, read_pos.inode },
+				read_pos.offset << 9));
+	if (ret)
+		return ret;
+
+	if (rbio->data_update)
+		prt_str(out, "(internal move) ");
+
+	return 0;
 }
 
 static void bch2_read_err_msg(struct bch_fs *c, struct printbuf *out,
@@ -341,10 +368,6 @@ static void bch2_read_err_msg(struct bch_fs *c, struct printbuf *out,
 	bch2_trans_run(c, bch2_read_err_msg_trans(trans, out, rbio, read_pos));
 }
 
-#define READ_RETRY_AVOID	1
-#define READ_RETRY		2
-#define READ_ERR		3
-
 enum rbio_context {
 	RBIO_CONTEXT_NULL,
 	RBIO_CONTEXT_HIGHPRI,
@@ -375,20 +398,25 @@ static inline struct bch_read_bio *bch2_rbio_free(struct bch_read_bio *rbio)
 {
 	BUG_ON(rbio->bounce && !rbio->split);
 
-	if (rbio->promote)
-		promote_free(rbio->c, rbio->promote);
-	rbio->promote = NULL;
-
-	if (rbio->bounce)
-		bch2_bio_free_pages_pool(rbio->c, &rbio->bio);
+	if (rbio->have_ioref) {
+		struct bch_dev *ca = bch2_dev_have_ref(rbio->c, rbio->pick.ptr.dev);
+		percpu_ref_put(&ca->io_ref);
+	}
 
 	if (rbio->split) {
 		struct bch_read_bio *parent = rbio->parent;
 
-		if (rbio->kmalloc)
-			kfree(rbio);
-		else
+		if (unlikely(rbio->promote)) {
+			if (!rbio->bio.bi_status)
+				promote_start(rbio);
+			else
+				promote_free(rbio);
+		} else {
+			if (rbio->bounce)
+				bch2_bio_free_pages_pool(rbio->c, &rbio->bio);
+
 			bio_put(&rbio->bio);
+		}
 
 		rbio = parent;
 	}
@@ -408,61 +436,115 @@ static void bch2_rbio_done(struct bch_read_bio *rbio)
 	bio_endio(&rbio->bio);
 }
 
-static void bch2_read_retry_nodecode(struct bch_fs *c, struct bch_read_bio *rbio,
-				     struct bvec_iter bvec_iter,
-				     struct bch_io_failures *failed,
-				     unsigned flags)
+static void get_rbio_extent(struct btree_trans *trans,
+			    struct bch_read_bio *rbio,
+			    struct bkey_buf *sk)
 {
-	struct btree_trans *trans = bch2_trans_get(c);
 	struct btree_iter iter;
-	struct bkey_buf sk;
 	struct bkey_s_c k;
-	int ret;
+	int ret = lockrestart_do(trans,
+			bkey_err(k = bch2_bkey_get_iter(trans, &iter,
+						rbio->data_btree, rbio->data_pos, 0)));
+	if (ret)
+		return;
+
+	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+	bkey_for_each_ptr(ptrs, ptr)
+		if (bch2_extent_ptr_eq(*ptr, rbio->pick.ptr)) {
+			bch2_bkey_buf_reassemble(sk, trans->c, k);
+			break;
+		}
 
-	flags &= ~BCH_READ_LAST_FRAGMENT;
-	flags |= BCH_READ_MUST_CLONE;
+	bch2_trans_iter_exit(trans, &iter);
+}
 
-	bch2_bkey_buf_init(&sk);
+static noinline int maybe_poison_extent(struct btree_trans *trans, struct bch_read_bio *rbio,
+					enum btree_id btree, struct bkey_s_c read_k)
+{
+	struct bch_fs *c = trans->c;
+
+	struct data_update *u = rbio_data_update(rbio);
+	if (u)
+		read_k = bkey_i_to_s_c(u->k.k);
+
+	u64 flags = bch2_bkey_extent_flags(read_k);
+	if (flags & BIT_ULL(BCH_EXTENT_FLAG_poisoned))
+		return 0;
+
+	struct btree_iter iter;
+	struct bkey_s_c k = bch2_bkey_get_iter(trans, &iter, btree, bkey_start_pos(read_k.k),
+					       BTREE_ITER_intent);
+	int ret = bkey_err(k);
+	if (ret)
+		return ret;
+
+	if (!bkey_and_val_eq(k, read_k))
+		goto out;
+
+	struct bkey_i *new = bch2_trans_kmalloc(trans,
+					bkey_bytes(k.k) + sizeof(struct bch_extent_flags));
+	ret =   PTR_ERR_OR_ZERO(new) ?:
+		(bkey_reassemble(new, k), 0) ?:
+		bch2_bkey_extent_flags_set(c, new, flags|BIT_ULL(BCH_EXTENT_FLAG_poisoned)) ?:
+		bch2_trans_update(trans, &iter, new, BTREE_UPDATE_internal_snapshot_node) ?:
+		bch2_trans_commit(trans, NULL, NULL, 0);
+
+	/*
+	 * Propagate key change back to data update path, in particular so it
+	 * knows the extent has been poisoned and it's safe to change the
+	 * checksum
+	 */
+	if (u && !ret)
+		bch2_bkey_buf_copy(&u->k, c, new);
+out:
+	bch2_trans_iter_exit(trans, &iter);
+	return ret;
+}
 
-	bch2_trans_iter_init(trans, &iter, rbio->data_btree,
-			     rbio->read_pos, BTREE_ITER_slots);
+static noinline int bch2_read_retry_nodecode(struct btree_trans *trans,
+					struct bch_read_bio *rbio,
+					struct bvec_iter bvec_iter,
+					struct bch_io_failures *failed,
+					unsigned flags)
+{
+	struct data_update *u = container_of(rbio, struct data_update, rbio);
 retry:
 	bch2_trans_begin(trans);
-	rbio->bio.bi_status = 0;
 
-	ret = lockrestart_do(trans, bkey_err(k = bch2_btree_iter_peek_slot(&iter)));
+	struct btree_iter iter;
+	struct bkey_s_c k;
+	int ret = lockrestart_do(trans,
+		bkey_err(k = bch2_bkey_get_iter(trans, &iter,
+				u->btree_id, bkey_start_pos(&u->k.k->k),
+				0)));
 	if (ret)
 		goto err;
 
-	bch2_bkey_buf_reassemble(&sk, c, k);
-	k = bkey_i_to_s_c(sk.k);
-
-	if (!bch2_bkey_matches_ptr(c, k,
-				   rbio->pick.ptr,
-				   rbio->data_pos.offset -
-				   rbio->pick.crc.offset)) {
+	if (!bkey_and_val_eq(k, bkey_i_to_s_c(u->k.k))) {
 		/* extent we wanted to read no longer exists: */
-		rbio->hole = true;
-		goto out;
+		rbio->ret = -BCH_ERR_data_read_key_overwritten;
+		goto err;
 	}
 
 	ret = __bch2_read_extent(trans, rbio, bvec_iter,
-				 rbio->read_pos,
-				 rbio->data_btree,
-				 k, 0, failed, flags);
-	if (ret == READ_RETRY)
-		goto retry;
-	if (ret)
-		goto err;
-out:
-	bch2_rbio_done(rbio);
-	bch2_trans_iter_exit(trans, &iter);
-	bch2_trans_put(trans);
-	bch2_bkey_buf_exit(&sk, c);
-	return;
+				 bkey_start_pos(&u->k.k->k),
+				 u->btree_id,
+				 bkey_i_to_s_c(u->k.k),
+				 0, failed, flags, -1);
 err:
-	rbio->bio.bi_status = BLK_STS_IOERR;
-	goto out;
+	bch2_trans_iter_exit(trans, &iter);
+
+	if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||
+	    bch2_err_matches(ret, BCH_ERR_data_read_retry))
+		goto retry;
+
+	if (ret) {
+		rbio->bio.bi_status	= BLK_STS_IOERR;
+		rbio->ret		= ret;
+	}
+
+	BUG_ON(atomic_read(&rbio->bio.__bi_remaining) != 1);
+	return ret;
 }
 
 static void bch2_rbio_retry(struct work_struct *work)
@@ -478,44 +560,88 @@ static void bch2_rbio_retry(struct work_struct *work)
 	};
 	struct bch_io_failures failed = { .nr = 0 };
 
-	trace_and_count(c, read_retry, &rbio->bio);
+	struct btree_trans *trans = bch2_trans_get(c);
+
+	struct bkey_buf sk;
+	bch2_bkey_buf_init(&sk);
+	bkey_init(&sk.k->k);
 
-	if (rbio->retry == READ_RETRY_AVOID)
-		bch2_mark_io_failure(&failed, &rbio->pick);
+	trace_io_read_retry(&rbio->bio);
+	this_cpu_add(c->counters[BCH_COUNTER_io_read_retry],
+		     bvec_iter_sectors(rbio->bvec_iter));
 
-	rbio->bio.bi_status = 0;
+	get_rbio_extent(trans, rbio, &sk);
+
+	if (!bkey_deleted(&sk.k->k) &&
+	    bch2_err_matches(rbio->ret, BCH_ERR_data_read_retry_avoid))
+		bch2_mark_io_failure(&failed, &rbio->pick,
+				     rbio->ret == -BCH_ERR_data_read_retry_csum_err);
+
+	if (!rbio->split) {
+		rbio->bio.bi_status	= 0;
+		rbio->ret		= 0;
+	}
+
+	unsigned subvol		= rbio->subvol;
+	struct bpos read_pos	= rbio->read_pos;
 
 	rbio = bch2_rbio_free(rbio);
 
-	flags |= BCH_READ_IN_RETRY;
-	flags &= ~BCH_READ_MAY_PROMOTE;
+	flags |= BCH_READ_in_retry;
+	flags &= ~BCH_READ_may_promote;
+	flags &= ~BCH_READ_last_fragment;
+	flags |= BCH_READ_must_clone;
 
-	if (flags & BCH_READ_NODECODE) {
-		bch2_read_retry_nodecode(c, rbio, iter, &failed, flags);
+	int ret = rbio->data_update
+		? bch2_read_retry_nodecode(trans, rbio, iter, &failed, flags)
+		: __bch2_read(trans, rbio, iter, inum, &failed, &sk, flags);
+
+	if (ret) {
+		rbio->ret = ret;
+		rbio->bio.bi_status = BLK_STS_IOERR;
 	} else {
-		flags &= ~BCH_READ_LAST_FRAGMENT;
-		flags |= BCH_READ_MUST_CLONE;
+		struct printbuf buf = PRINTBUF;
 
-		__bch2_read(c, rbio, iter, inum, &failed, flags);
+		lockrestart_do(trans,
+			bch2_inum_offset_err_msg_trans(trans, &buf,
+					(subvol_inum) { subvol, read_pos.inode },
+					read_pos.offset << 9));
+		if (rbio->data_update)
+			prt_str(&buf, "(internal move) ");
+		prt_str(&buf, "successful retry");
+
+		bch_err_ratelimited(c, "%s", buf.buf);
+		printbuf_exit(&buf);
 	}
+
+	bch2_rbio_done(rbio);
+	bch2_bkey_buf_exit(&sk, c);
+	bch2_trans_put(trans);
 }
 
-static void bch2_rbio_error(struct bch_read_bio *rbio, int retry,
-			    blk_status_t error)
+static void bch2_rbio_error(struct bch_read_bio *rbio,
+			    int ret, blk_status_t blk_error)
 {
-	rbio->retry = retry;
+	BUG_ON(ret >= 0);
+
+	rbio->ret		= ret;
+	rbio->bio.bi_status	= blk_error;
 
-	if (rbio->flags & BCH_READ_IN_RETRY)
+	bch2_rbio_parent(rbio)->saw_error = true;
+
+	if (rbio->flags & BCH_READ_in_retry)
 		return;
 
-	if (retry == READ_ERR) {
+	if (bch2_err_matches(ret, BCH_ERR_data_read_retry)) {
+		bch2_rbio_punt(rbio, bch2_rbio_retry,
+			       RBIO_CONTEXT_UNBOUND, system_unbound_wq);
+	} else {
 		rbio = bch2_rbio_free(rbio);
 
-		rbio->bio.bi_status = error;
+		rbio->ret		= ret;
+		rbio->bio.bi_status	= blk_error;
+
 		bch2_rbio_done(rbio);
-	} else {
-		bch2_rbio_punt(rbio, bch2_rbio_retry,
-			       RBIO_CONTEXT_UNBOUND, system_unbound_wq);
 	}
 }
 
@@ -531,15 +657,13 @@ static void bch2_read_io_err(struct work_struct *work)
 	bch2_read_err_msg(c, &buf, rbio, rbio->read_pos);
 	prt_printf(&buf, "data read error: %s", bch2_blk_status_to_str(bio->bi_status));
 
-	if (ca) {
-		bch2_io_error(ca, BCH_MEMBER_ERROR_read);
+	if (ca)
 		bch_err_ratelimited(ca, "%s", buf.buf);
-	} else {
+	else
 		bch_err_ratelimited(c, "%s", buf.buf);
-	}
 
 	printbuf_exit(&buf);
-	bch2_rbio_error(rbio, READ_RETRY_AVOID, bio->bi_status);
+	bch2_rbio_error(rbio, -BCH_ERR_data_read_retry_io_err, bio->bi_status);
 }
 
 static int __bch2_rbio_narrow_crcs(struct btree_trans *trans,
@@ -621,14 +745,12 @@ static void bch2_read_csum_err(struct work_struct *work)
 	bch2_csum_err_msg(&buf, crc.csum_type, rbio->pick.crc.csum, csum);
 
 	struct bch_dev *ca = rbio->have_ioref ? bch2_dev_have_ref(c, rbio->pick.ptr.dev) : NULL;
-	if (ca) {
-		bch2_io_error(ca, BCH_MEMBER_ERROR_checksum);
+	if (ca)
 		bch_err_ratelimited(ca, "%s", buf.buf);
-	} else {
+	else
 		bch_err_ratelimited(c, "%s", buf.buf);
-	}
 
-	bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR);
+	bch2_rbio_error(rbio, -BCH_ERR_data_read_retry_csum_err, BLK_STS_IOERR);
 	printbuf_exit(&buf);
 }
 
@@ -648,7 +770,7 @@ static void bch2_read_decompress_err(struct work_struct *work)
 	else
 		bch_err_ratelimited(c, "%s", buf.buf);
 
-	bch2_rbio_error(rbio, READ_ERR, BLK_STS_IOERR);
+	bch2_rbio_error(rbio, -BCH_ERR_data_read_decompress_err, BLK_STS_IOERR);
 	printbuf_exit(&buf);
 }
 
@@ -668,7 +790,7 @@ static void bch2_read_decrypt_err(struct work_struct *work)
 	else
 		bch_err_ratelimited(c, "%s", buf.buf);
 
-	bch2_rbio_error(rbio, READ_ERR, BLK_STS_IOERR);
+	bch2_rbio_error(rbio, -BCH_ERR_data_read_decrypt_err, BLK_STS_IOERR);
 	printbuf_exit(&buf);
 }
 
@@ -678,9 +800,11 @@ static void __bch2_read_endio(struct work_struct *work)
 	struct bch_read_bio *rbio =
 		container_of(work, struct bch_read_bio, work);
 	struct bch_fs *c	= rbio->c;
-	struct bio *src		= &rbio->bio;
-	struct bio *dst		= &bch2_rbio_parent(rbio)->bio;
-	struct bvec_iter dst_iter = rbio->bvec_iter;
+	struct bch_dev *ca = rbio->have_ioref ? bch2_dev_have_ref(c, rbio->pick.ptr.dev) : NULL;
+	struct bch_read_bio *parent	= bch2_rbio_parent(rbio);
+	struct bio *src			= &rbio->bio;
+	struct bio *dst			= &parent->bio;
+	struct bvec_iter dst_iter	= rbio->bvec_iter;
 	struct bch_extent_crc_unpacked crc = rbio->pick.crc;
 	struct nonce nonce = extent_nonce(rbio->version, crc);
 	unsigned nofs_flags;
@@ -698,8 +822,26 @@ static void __bch2_read_endio(struct work_struct *work)
 		src->bi_iter			= rbio->bvec_iter;
 	}
 
+	bch2_maybe_corrupt_bio(src, bch2_read_corrupt_ratio);
+
 	csum = bch2_checksum_bio(c, crc.csum_type, nonce, src);
-	if (bch2_crc_cmp(csum, rbio->pick.crc.csum) && !c->opts.no_data_io)
+	bool csum_good = !bch2_crc_cmp(csum, rbio->pick.crc.csum) || c->opts.no_data_io;
+
+	/*
+	 * Checksum error: if the bio wasn't bounced, we may have been
+	 * reading into buffers owned by userspace (that userspace can
+	 * scribble over) - retry the read, bouncing it this time:
+	 */
+	if (!csum_good && !rbio->bounce && (rbio->flags & BCH_READ_user_mapped)) {
+		rbio->flags |= BCH_READ_must_bounce;
+		bch2_rbio_error(rbio, -BCH_ERR_data_read_retry_csum_err_maybe_userspace,
+				BLK_STS_IOERR);
+		goto out;
+	}
+
+	bch2_account_io_completion(ca, BCH_MEMBER_ERROR_checksum, 0, csum_good);
+
+	if (!csum_good)
 		goto csum_err;
 
 	/*
@@ -712,32 +854,40 @@ static void __bch2_read_endio(struct work_struct *work)
 	if (unlikely(rbio->narrow_crcs))
 		bch2_rbio_narrow_crcs(rbio);
 
-	if (rbio->flags & BCH_READ_NODECODE)
-		goto nodecode;
+	if (likely(!parent->data_update)) {
+		/* Adjust crc to point to subset of data we want: */
+		crc.offset     += rbio->offset_into_extent;
+		crc.live_size	= bvec_iter_sectors(rbio->bvec_iter);
 
-	/* Adjust crc to point to subset of data we want: */
-	crc.offset     += rbio->offset_into_extent;
-	crc.live_size	= bvec_iter_sectors(rbio->bvec_iter);
+		if (crc_is_compressed(crc)) {
+			ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src);
+			if (ret)
+				goto decrypt_err;
 
-	if (crc_is_compressed(crc)) {
-		ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src);
-		if (ret)
-			goto decrypt_err;
+			if (bch2_bio_uncompress(c, src, dst, dst_iter, crc) &&
+			    !c->opts.no_data_io)
+				goto decompression_err;
+		} else {
+			/* don't need to decrypt the entire bio: */
+			nonce = nonce_add(nonce, crc.offset << 9);
+			bio_advance(src, crc.offset << 9);
 
-		if (bch2_bio_uncompress(c, src, dst, dst_iter, crc) &&
-		    !c->opts.no_data_io)
-			goto decompression_err;
-	} else {
-		/* don't need to decrypt the entire bio: */
-		nonce = nonce_add(nonce, crc.offset << 9);
-		bio_advance(src, crc.offset << 9);
+			BUG_ON(src->bi_iter.bi_size < dst_iter.bi_size);
+			src->bi_iter.bi_size = dst_iter.bi_size;
 
-		BUG_ON(src->bi_iter.bi_size < dst_iter.bi_size);
-		src->bi_iter.bi_size = dst_iter.bi_size;
+			ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src);
+			if (ret)
+				goto decrypt_err;
 
-		ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src);
-		if (ret)
-			goto decrypt_err;
+			if (rbio->bounce) {
+				struct bvec_iter src_iter = src->bi_iter;
+
+				bio_copy_data_iter(dst, &dst_iter, src, &src_iter);
+			}
+		}
+	} else {
+		if (rbio->split)
+			rbio->parent->pick = rbio->pick;
 
 		if (rbio->bounce) {
 			struct bvec_iter src_iter = src->bi_iter;
@@ -754,12 +904,9 @@ static void __bch2_read_endio(struct work_struct *work)
 		ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src);
 		if (ret)
 			goto decrypt_err;
-
-		promote_start(rbio->promote, rbio);
-		rbio->promote = NULL;
 	}
-nodecode:
-	if (likely(!(rbio->flags & BCH_READ_IN_RETRY))) {
+
+	if (likely(!(rbio->flags & BCH_READ_in_retry))) {
 		rbio = bch2_rbio_free(rbio);
 		bch2_rbio_done(rbio);
 	}
@@ -767,17 +914,6 @@ static void __bch2_read_endio(struct work_struct *work)
 	memalloc_nofs_restore(nofs_flags);
 	return;
 csum_err:
-	/*
-	 * Checksum error: if the bio wasn't bounced, we may have been
-	 * reading into buffers owned by userspace (that userspace can
-	 * scribble over) - retry the read, bouncing it this time:
-	 */
-	if (!rbio->bounce && (rbio->flags & BCH_READ_USER_MAPPED)) {
-		rbio->flags |= BCH_READ_MUST_BOUNCE;
-		bch2_rbio_error(rbio, READ_RETRY, BLK_STS_IOERR);
-		goto out;
-	}
-
 	bch2_rbio_punt(rbio, bch2_read_csum_err, RBIO_CONTEXT_UNBOUND, system_unbound_wq);
 	goto out;
 decompression_err:
@@ -797,10 +933,8 @@ static void bch2_read_endio(struct bio *bio)
 	struct workqueue_struct *wq = NULL;
 	enum rbio_context context = RBIO_CONTEXT_NULL;
 
-	if (rbio->have_ioref) {
-		bch2_latency_acct(ca, rbio->submit_time, READ);
-		percpu_ref_put(&ca->io_ref);
-	}
+	bch2_account_io_completion(ca, BCH_MEMBER_ERROR_read,
+				   rbio->submit_time, !bio->bi_status);
 
 	if (!rbio->split)
 		rbio->bio.bi_end_io = rbio->end_io;
@@ -810,14 +944,14 @@ static void bch2_read_endio(struct bio *bio)
 		return;
 	}
 
-	if (((rbio->flags & BCH_READ_RETRY_IF_STALE) && race_fault()) ||
+	if (((rbio->flags & BCH_READ_retry_if_stale) && race_fault()) ||
 	    (ca && dev_ptr_stale(ca, &rbio->pick.ptr))) {
-		trace_and_count(c, read_reuse_race, &rbio->bio);
+		trace_and_count(c, io_read_reuse_race, &rbio->bio);
 
-		if (rbio->flags & BCH_READ_RETRY_IF_STALE)
-			bch2_rbio_error(rbio, READ_RETRY, BLK_STS_AGAIN);
+		if (rbio->flags & BCH_READ_retry_if_stale)
+			bch2_rbio_error(rbio, -BCH_ERR_data_read_ptr_stale_retry, BLK_STS_AGAIN);
 		else
-			bch2_rbio_error(rbio, READ_ERR, BLK_STS_AGAIN);
+			bch2_rbio_error(rbio, -BCH_ERR_data_read_ptr_stale_race, BLK_STS_AGAIN);
 		return;
 	}
 
@@ -883,15 +1017,15 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 		       struct bvec_iter iter, struct bpos read_pos,
 		       enum btree_id data_btree, struct bkey_s_c k,
 		       unsigned offset_into_extent,
-		       struct bch_io_failures *failed, unsigned flags)
+		       struct bch_io_failures *failed, unsigned flags, int dev)
 {
 	struct bch_fs *c = trans->c;
 	struct extent_ptr_decoded pick;
 	struct bch_read_bio *rbio = NULL;
-	struct promote_op *promote = NULL;
 	bool bounce = false, read_full = false, narrow_crcs = false;
 	struct bpos data_pos = bkey_start_pos(k.k);
-	int pick_ret;
+	struct data_update *u = rbio_data_update(orig);
+	int ret = 0;
 
 	if (bkey_extent_is_inline_data(k.k)) {
 		unsigned bytes = min_t(unsigned, iter.bi_size,
@@ -902,19 +1036,35 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 		swap(iter.bi_size, bytes);
 		bio_advance_iter(&orig->bio, &iter, bytes);
 		zero_fill_bio_iter(&orig->bio, iter);
+		this_cpu_add(c->counters[BCH_COUNTER_io_read_inline],
+			     bvec_iter_sectors(iter));
 		goto out_read_done;
 	}
+
+	if ((bch2_bkey_extent_flags(k) & BIT_ULL(BCH_EXTENT_FLAG_poisoned)) &&
+	    !orig->data_update)
+		return -BCH_ERR_extent_poisened;
 retry_pick:
-	pick_ret = bch2_bkey_pick_read_device(c, k, failed, &pick);
+	ret = bch2_bkey_pick_read_device(c, k, failed, &pick, dev);
 
 	/* hole or reservation - just zero fill: */
-	if (!pick_ret)
+	if (!ret)
 		goto hole;
 
-	if (unlikely(pick_ret < 0)) {
+	if (unlikely(ret < 0)) {
+		if (ret == -BCH_ERR_data_read_csum_err) {
+			int ret2 = maybe_poison_extent(trans, orig, data_btree, k);
+			if (ret2) {
+				ret = ret2;
+				goto err;
+			}
+
+			trace_and_count(c, io_read_fail_and_poison, &orig->bio);
+		}
+
 		struct printbuf buf = PRINTBUF;
 		bch2_read_err_msg_trans(trans, &buf, orig, read_pos);
-		prt_printf(&buf, "no device to read from: %s\n  ", bch2_err_str(pick_ret));
+		prt_printf(&buf, "%s\n  ", bch2_err_str(ret));
 		bch2_bkey_val_to_text(&buf, c, k);
 
 		bch_err_ratelimited(c, "%s", buf.buf);
@@ -930,6 +1080,7 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 
 		bch_err_ratelimited(c, "%s", buf.buf);
 		printbuf_exit(&buf);
+		ret = -BCH_ERR_data_read_no_encryption_key;
 		goto err;
 	}
 
@@ -941,56 +1092,57 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 	 * retry path, don't check here, it'll be caught in bch2_read_endio()
 	 * and we'll end up in the retry path:
 	 */
-	if ((flags & BCH_READ_IN_RETRY) &&
+	if ((flags & BCH_READ_in_retry) &&
 	    !pick.ptr.cached &&
 	    ca &&
 	    unlikely(dev_ptr_stale(ca, &pick.ptr))) {
 		read_from_stale_dirty_pointer(trans, ca, k, pick.ptr);
-		bch2_mark_io_failure(failed, &pick);
+		bch2_mark_io_failure(failed, &pick, false);
 		percpu_ref_put(&ca->io_ref);
 		goto retry_pick;
 	}
 
-	if (flags & BCH_READ_NODECODE) {
+	if (likely(!u)) {
+		if (!(flags & BCH_READ_last_fragment) ||
+		    bio_flagged(&orig->bio, BIO_CHAIN))
+			flags |= BCH_READ_must_clone;
+
+		narrow_crcs = !(flags & BCH_READ_in_retry) &&
+			bch2_can_narrow_extent_crcs(k, pick.crc);
+
+		if (narrow_crcs && (flags & BCH_READ_user_mapped))
+			flags |= BCH_READ_must_bounce;
+
+		EBUG_ON(offset_into_extent + bvec_iter_sectors(iter) > k.k->size);
+
+		if (crc_is_compressed(pick.crc) ||
+		    (pick.crc.csum_type != BCH_CSUM_none &&
+		     (bvec_iter_sectors(iter) != pick.crc.uncompressed_size ||
+		      (bch2_csum_type_is_encryption(pick.crc.csum_type) &&
+		       (flags & BCH_READ_user_mapped)) ||
+		      (flags & BCH_READ_must_bounce)))) {
+			read_full = true;
+			bounce = true;
+		}
+	} else {
 		/*
 		 * can happen if we retry, and the extent we were going to read
 		 * has been merged in the meantime:
 		 */
-		if (pick.crc.compressed_size > orig->bio.bi_vcnt * PAGE_SECTORS) {
+		if (pick.crc.compressed_size > u->op.wbio.bio.bi_iter.bi_size) {
 			if (ca)
 				percpu_ref_put(&ca->io_ref);
-			goto hole;
+			rbio->ret = -BCH_ERR_data_read_buffer_too_small;
+			goto out_read_done;
 		}
 
 		iter.bi_size	= pick.crc.compressed_size << 9;
-		goto get_bio;
-	}
-
-	if (!(flags & BCH_READ_LAST_FRAGMENT) ||
-	    bio_flagged(&orig->bio, BIO_CHAIN))
-		flags |= BCH_READ_MUST_CLONE;
-
-	narrow_crcs = !(flags & BCH_READ_IN_RETRY) &&
-		bch2_can_narrow_extent_crcs(k, pick.crc);
-
-	if (narrow_crcs && (flags & BCH_READ_USER_MAPPED))
-		flags |= BCH_READ_MUST_BOUNCE;
-
-	EBUG_ON(offset_into_extent + bvec_iter_sectors(iter) > k.k->size);
-
-	if (crc_is_compressed(pick.crc) ||
-	    (pick.crc.csum_type != BCH_CSUM_none &&
-	     (bvec_iter_sectors(iter) != pick.crc.uncompressed_size ||
-	      (bch2_csum_type_is_encryption(pick.crc.csum_type) &&
-	       (flags & BCH_READ_USER_MAPPED)) ||
-	      (flags & BCH_READ_MUST_BOUNCE)))) {
 		read_full = true;
-		bounce = true;
 	}
 
 	if (orig->opts.promote_target || have_io_error(failed))
-		promote = promote_alloc(trans, iter, k, &pick, orig->opts, flags,
-					&rbio, &bounce, &read_full, failed);
+		rbio = promote_alloc(trans, iter, k, &pick, flags, orig,
+				     &bounce, &read_full, failed);
 
 	if (!read_full) {
 		EBUG_ON(crc_is_compressed(pick.crc));
@@ -1009,7 +1161,7 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 		pick.crc.offset			= 0;
 		pick.crc.live_size		= bvec_iter_sectors(iter);
 	}
-get_bio:
+
 	if (rbio) {
 		/*
 		 * promote already allocated bounce rbio:
@@ -1024,17 +1176,16 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 	} else if (bounce) {
 		unsigned sectors = pick.crc.compressed_size;
 
-		rbio = rbio_init(bio_alloc_bioset(NULL,
+		rbio = rbio_init_fragment(bio_alloc_bioset(NULL,
 						  DIV_ROUND_UP(sectors, PAGE_SECTORS),
 						  0,
 						  GFP_NOFS,
 						  &c->bio_read_split),
-				 orig->opts);
+				 orig);
 
 		bch2_bio_alloc_pages_pool(c, &rbio->bio, sectors << 9);
 		rbio->bounce	= true;
-		rbio->split	= true;
-	} else if (flags & BCH_READ_MUST_CLONE) {
+	} else if (flags & BCH_READ_must_clone) {
 		/*
 		 * Have to clone if there were any splits, due to error
 		 * reporting issues (if a split errored, and retrying didn't
@@ -1043,11 +1194,10 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 		 * from the whole bio, in which case we don't want to retry and
 		 * lose the error)
 		 */
-		rbio = rbio_init(bio_alloc_clone(NULL, &orig->bio, GFP_NOFS,
+		rbio = rbio_init_fragment(bio_alloc_clone(NULL, &orig->bio, GFP_NOFS,
 						 &c->bio_read_split),
-				 orig->opts);
+				 orig);
 		rbio->bio.bi_iter = iter;
-		rbio->split	= true;
 	} else {
 		rbio = orig;
 		rbio->bio.bi_iter = iter;
@@ -1056,67 +1206,64 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 
 	EBUG_ON(bio_sectors(&rbio->bio) != pick.crc.compressed_size);
 
-	rbio->c			= c;
 	rbio->submit_time	= local_clock();
-	if (rbio->split)
-		rbio->parent	= orig;
-	else
+	if (!rbio->split)
 		rbio->end_io	= orig->bio.bi_end_io;
 	rbio->bvec_iter		= iter;
 	rbio->offset_into_extent= offset_into_extent;
 	rbio->flags		= flags;
 	rbio->have_ioref	= ca != NULL;
 	rbio->narrow_crcs	= narrow_crcs;
-	rbio->hole		= 0;
-	rbio->retry		= 0;
+	rbio->ret		= 0;
 	rbio->context		= 0;
-	/* XXX: only initialize this if needed */
-	rbio->devs_have		= bch2_bkey_devs(k);
 	rbio->pick		= pick;
 	rbio->subvol		= orig->subvol;
 	rbio->read_pos		= read_pos;
 	rbio->data_btree	= data_btree;
 	rbio->data_pos		= data_pos;
 	rbio->version		= k.k->bversion;
-	rbio->promote		= promote;
 	INIT_WORK(&rbio->work, NULL);
 
-	if (flags & BCH_READ_NODECODE)
-		orig->pick = pick;
-
 	rbio->bio.bi_opf	= orig->bio.bi_opf;
 	rbio->bio.bi_iter.bi_sector = pick.ptr.offset;
 	rbio->bio.bi_end_io	= bch2_read_endio;
 
+	/* XXX: also nvme read recovery level */
+	if (unlikely(failed && bch2_dev_io_failures(failed, pick.ptr.dev)))
+		rbio->bio.bi_opf |= REQ_FUA;
+
 	if (rbio->bounce)
-		trace_and_count(c, read_bounce, &rbio->bio);
+		trace_and_count(c, io_read_bounce, &rbio->bio);
 
-	this_cpu_add(c->counters[BCH_COUNTER_io_read], bio_sectors(&rbio->bio));
+	if (!u)
+		this_cpu_add(c->counters[BCH_COUNTER_io_read], bio_sectors(&rbio->bio));
+	else
+		this_cpu_add(c->counters[BCH_COUNTER_io_move_read], bio_sectors(&rbio->bio));
 	bch2_increment_clock(c, bio_sectors(&rbio->bio), READ);
 
 	/*
 	 * If it's being moved internally, we don't want to flag it as a cache
 	 * hit:
 	 */
-	if (ca && pick.ptr.cached && !(flags & BCH_READ_NODECODE))
+	if (ca && pick.ptr.cached && !u)
 		bch2_bucket_io_time_reset(trans, pick.ptr.dev,
 			PTR_BUCKET_NR(ca, &pick.ptr), READ);
 
-	if (!(flags & (BCH_READ_IN_RETRY|BCH_READ_LAST_FRAGMENT))) {
+	if (!(flags & (BCH_READ_in_retry|BCH_READ_last_fragment))) {
 		bio_inc_remaining(&orig->bio);
-		trace_and_count(c, read_split, &orig->bio);
+		trace_and_count(c, io_read_split, &orig->bio);
 	}
 
 	/*
 	 * Unlock the iterator while the btree node's lock is still in
 	 * cache, before doing the IO:
 	 */
-	if (!(flags & BCH_READ_IN_RETRY))
+	if (!(flags & BCH_READ_in_retry))
 		bch2_trans_unlock(trans);
 	else
 		bch2_trans_unlock_long(trans);
 
-	if (!rbio->pick.idx) {
+	if (likely(!rbio->pick.do_ec_reconstruct)) {
 		if (unlikely(!rbio->have_ioref)) {
 			struct printbuf buf = PRINTBUF;
 			bch2_read_err_msg_trans(trans, &buf, rbio, read_pos);
@@ -1126,7 +1273,9 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 			bch_err_ratelimited(c, "%s", buf.buf);
 			printbuf_exit(&buf);
 
-			bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR);
+			bch2_rbio_error(rbio,
+					-BCH_ERR_data_read_retry_device_offline,
+					BLK_STS_IOERR);
 			goto out;
 		}
 
@@ -1135,10 +1284,10 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 		bio_set_dev(&rbio->bio, ca->disk_sb.bdev);
 
 		if (unlikely(c->opts.no_data_io)) {
-			if (likely(!(flags & BCH_READ_IN_RETRY)))
+			if (likely(!(flags & BCH_READ_in_retry)))
 				bio_endio(&rbio->bio);
 		} else {
-			if (likely(!(flags & BCH_READ_IN_RETRY)))
+			if (likely(!(flags & BCH_READ_in_retry)))
 				submit_bio(&rbio->bio);
 			else
 				submit_bio_wait(&rbio->bio);
@@ -1152,15 +1301,16 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 	} else {
 		/* Attempting reconstruct read: */
 		if (bch2_ec_read_extent(trans, rbio, k)) {
-			bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR);
+			bch2_rbio_error(rbio, -BCH_ERR_data_read_retry_ec_reconstruct_err,
+					BLK_STS_IOERR);
 			goto out;
 		}
 
-		if (likely(!(flags & BCH_READ_IN_RETRY)))
+		if (likely(!(flags & BCH_READ_in_retry)))
 			bio_endio(&rbio->bio);
 	}
 out:
-	if (likely(!(flags & BCH_READ_IN_RETRY))) {
+	if (likely(!(flags & BCH_READ_in_retry))) {
 		return 0;
 	} else {
 		bch2_trans_unlock(trans);
@@ -1170,54 +1320,57 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 		rbio->context = RBIO_CONTEXT_UNBOUND;
 		bch2_read_endio(&rbio->bio);
 
-		ret = rbio->retry;
+		ret = rbio->ret;
 		rbio = bch2_rbio_free(rbio);
 
-		if (ret == READ_RETRY_AVOID) {
-			bch2_mark_io_failure(failed, &pick);
-			ret = READ_RETRY;
-		}
-
-		if (!ret)
-			goto out_read_done;
+		if (bch2_err_matches(ret, BCH_ERR_data_read_retry_avoid))
+			bch2_mark_io_failure(failed, &pick,
+					ret == -BCH_ERR_data_read_retry_csum_err);
 
 		return ret;
 	}
 
 err:
-	if (flags & BCH_READ_IN_RETRY)
-		return READ_ERR;
+	if (flags & BCH_READ_in_retry)
+		return ret;
 
-	orig->bio.bi_status = BLK_STS_IOERR;
+	orig->bio.bi_status	= BLK_STS_IOERR;
+	orig->ret		= ret;
 	goto out_read_done;
 
 hole:
+	this_cpu_add(c->counters[BCH_COUNTER_io_read_hole],
+		     bvec_iter_sectors(iter));
 	/*
-	 * won't normally happen in the BCH_READ_NODECODE
-	 * (bch2_move_extent()) path, but if we retry and the extent we wanted
-	 * to read no longer exists we have to signal that:
+	 * won't normally happen in the data update (bch2_move_extent()) path,
+	 * but if we retry and the extent we wanted to read no longer exists we
+	 * have to signal that:
 	 */
-	if (flags & BCH_READ_NODECODE)
-		orig->hole = true;
+	if (u)
+		orig->ret = -BCH_ERR_data_read_key_overwritten;
 
 	zero_fill_bio_iter(&orig->bio, iter);
 out_read_done:
-	if (flags & BCH_READ_LAST_FRAGMENT)
+	if ((flags & BCH_READ_last_fragment) &&
+	    !(flags & BCH_READ_in_retry))
 		bch2_rbio_done(orig);
 	return 0;
 }
 
-void __bch2_read(struct bch_fs *c, struct bch_read_bio *rbio,
-		 struct bvec_iter bvec_iter, subvol_inum inum,
-		 struct bch_io_failures *failed, unsigned flags)
+int __bch2_read(struct btree_trans *trans, struct bch_read_bio *rbio,
+		struct bvec_iter bvec_iter, subvol_inum inum,
+		struct bch_io_failures *failed,
+		struct bkey_buf *prev_read,
+		unsigned flags)
 {
-	struct btree_trans *trans = bch2_trans_get(c);
+	struct bch_fs *c = trans->c;
 	struct btree_iter iter;
 	struct bkey_buf sk;
 	struct bkey_s_c k;
+	enum btree_id data_btree;
 	int ret;
 
-	BUG_ON(flags & BCH_READ_NODECODE);
+	EBUG_ON(rbio->data_update);
 
 	bch2_bkey_buf_init(&sk);
 	bch2_trans_iter_init(trans, &iter, BTREE_ID_extents,
@@ -1225,7 +1378,7 @@ void __bch2_read(struct bch_fs *c, struct bch_read_bio *rbio,
 			     BTREE_ITER_slots);
 
 	while (1) {
-		enum btree_id data_btree = BTREE_ID_extents;
+		data_btree = BTREE_ID_extents;
 
 		bch2_trans_begin(trans);
 
@@ -1257,6 +1410,12 @@ void __bch2_read(struct bch_fs *c, struct bch_read_bio *rbio,
 
 		k = bkey_i_to_s_c(sk.k);
 
+		if (unlikely(flags & BCH_READ_in_retry)) {
+			if (!bkey_and_val_eq(k, bkey_i_to_s_c(prev_read->k)))
+				failed->nr = 0;
+			bch2_bkey_buf_copy(prev_read, c, sk.k);
+		}
+
 		/*
 		 * With indirect extents, the amount of data to read is the min
 		 * of the original extent and the indirect extent:
@@ -1267,42 +1426,49 @@ void __bch2_read(struct bch_fs *c, struct bch_read_bio *rbio,
 		swap(bvec_iter.bi_size, bytes);
 
 		if (bvec_iter.bi_size == bytes)
-			flags |= BCH_READ_LAST_FRAGMENT;
+			flags |= BCH_READ_last_fragment;
 
 		ret = __bch2_read_extent(trans, rbio, bvec_iter, iter.pos,
 					 data_btree, k,
-					 offset_into_extent, failed, flags);
+					 offset_into_extent, failed, flags, -1);
+		swap(bvec_iter.bi_size, bytes);
+
 		if (ret)
 			goto err;
 
-		if (flags & BCH_READ_LAST_FRAGMENT)
+		if (flags & BCH_READ_last_fragment)
 			break;
 
-		swap(bvec_iter.bi_size, bytes);
 		bio_advance_iter(&rbio->bio, &bvec_iter, bytes);
 err:
+		if (ret == -BCH_ERR_data_read_retry_csum_err_maybe_userspace)
+			flags |= BCH_READ_must_bounce;
+
 		if (ret &&
 		    !bch2_err_matches(ret, BCH_ERR_transaction_restart) &&
-		    ret != READ_RETRY &&
-		    ret != READ_RETRY_AVOID)
+		    !bch2_err_matches(ret, BCH_ERR_data_read_retry))
 			break;
 	}
 
-	bch2_trans_iter_exit(trans, &iter);
-
-	if (ret) {
+	if (unlikely(ret)) {
 		struct printbuf buf = PRINTBUF;
-		bch2_inum_offset_err_msg_trans(trans, &buf, inum, bvec_iter.bi_sector << 9);
-		prt_printf(&buf, "read error %i from btree lookup", ret);
+		lockrestart_do(trans,
+			bch2_inum_offset_err_msg_trans(trans, &buf, inum,
+						       bvec_iter.bi_sector << 9));
+		prt_printf(&buf, "read error: %s", bch2_err_str(ret));
 		bch_err_ratelimited(c, "%s", buf.buf);
 		printbuf_exit(&buf);
 
-		rbio->bio.bi_status = BLK_STS_IOERR;
-		bch2_rbio_done(rbio);
+		rbio->bio.bi_status	= BLK_STS_IOERR;
+		rbio->ret		= ret;
+
+		if (!(flags & BCH_READ_in_retry))
+			bch2_rbio_done(rbio);
 	}
 
-	bch2_trans_put(trans);
+	bch2_trans_iter_exit(trans, &iter);
 	bch2_bkey_buf_exit(&sk, c);
+	return ret;
 }
 
 void bch2_fs_io_read_exit(struct bch_fs *c)
diff --git a/fs/bcachefs/io_read.h b/fs/bcachefs/io_read.h
index a82e8a94ccb6..1a85b092fd1d 100644
--- a/fs/bcachefs/io_read.h
+++ b/fs/bcachefs/io_read.h
@@ -3,6 +3,7 @@
 #define _BCACHEFS_IO_READ_H
 
 #include "bkey_buf.h"
+#include "btree_iter.h"
 #include "reflink.h"
 
 struct bch_read_bio {
@@ -35,19 +36,18 @@ struct bch_read_bio {
 	u16			flags;
 	union {
 	struct {
-	u16			bounce:1,
+	u16			data_update:1,
+				promote:1,
+				bounce:1,
 				split:1,
-				kmalloc:1,
 				have_ioref:1,
 				narrow_crcs:1,
-				hole:1,
-				retry:2,
+				saw_error:1,
 				context:2;
 	};
 	u16			_state;
 	};
-
-	struct bch_devs_list	devs_have;
+	s16			ret;
 
 	struct extent_ptr_decoded pick;
 
@@ -65,8 +65,6 @@ struct bch_read_bio {
 	struct bpos		data_pos;
 	struct bversion		version;
 
-	struct promote_op	*promote;
-
 	struct bch_io_opts	opts;
 
 	struct work_struct	work;
@@ -108,61 +106,90 @@ static inline int bch2_read_indirect_extent(struct btree_trans *trans,
 	return 0;
 }
 
+#define BCH_READ_FLAGS()		\
+	x(retry_if_stale)		\
+	x(may_promote)			\
+	x(user_mapped)			\
+	x(last_fragment)		\
+	x(must_bounce)			\
+	x(must_clone)			\
+	x(in_retry)
+
+enum __bch_read_flags {
+#define x(n)	__BCH_READ_##n,
+	BCH_READ_FLAGS()
+#undef x
+};
+
 enum bch_read_flags {
-	BCH_READ_RETRY_IF_STALE		= 1 << 0,
-	BCH_READ_MAY_PROMOTE		= 1 << 1,
-	BCH_READ_USER_MAPPED		= 1 << 2,
-	BCH_READ_NODECODE		= 1 << 3,
-	BCH_READ_LAST_FRAGMENT		= 1 << 4,
-
-	/* internal: */
-	BCH_READ_MUST_BOUNCE		= 1 << 5,
-	BCH_READ_MUST_CLONE		= 1 << 6,
-	BCH_READ_IN_RETRY		= 1 << 7,
+#define x(n)	BCH_READ_##n = BIT(__BCH_READ_##n),
+	BCH_READ_FLAGS()
+#undef x
 };
 
 int __bch2_read_extent(struct btree_trans *, struct bch_read_bio *,
 		       struct bvec_iter, struct bpos, enum btree_id,
 		       struct bkey_s_c, unsigned,
-		       struct bch_io_failures *, unsigned);
+		       struct bch_io_failures *, unsigned, int);
 
 static inline void bch2_read_extent(struct btree_trans *trans,
 			struct bch_read_bio *rbio, struct bpos read_pos,
 			enum btree_id data_btree, struct bkey_s_c k,
 			unsigned offset_into_extent, unsigned flags)
 {
-	__bch2_read_extent(trans, rbio, rbio->bio.bi_iter, read_pos,
-			   data_btree, k, offset_into_extent, NULL, flags);
+	int ret = __bch2_read_extent(trans, rbio, rbio->bio.bi_iter, read_pos,
+				     data_btree, k, offset_into_extent, NULL, flags, -1);
+	/* __bch2_read_extent only returns errors if BCH_READ_in_retry is set */
+	WARN(ret, "unhandled error from __bch2_read_extent()");
 }
 
-void __bch2_read(struct bch_fs *, struct bch_read_bio *, struct bvec_iter,
-		 subvol_inum, struct bch_io_failures *, unsigned flags);
+int __bch2_read(struct btree_trans *, struct bch_read_bio *, struct bvec_iter,
+		subvol_inum,
+		struct bch_io_failures *, struct bkey_buf *, unsigned flags);
 
 static inline void bch2_read(struct bch_fs *c, struct bch_read_bio *rbio,
 			     subvol_inum inum)
 {
-	struct bch_io_failures failed = { .nr = 0 };
-
 	BUG_ON(rbio->_state);
 
-	rbio->c = c;
-	rbio->start_time = local_clock();
 	rbio->subvol = inum.subvol;
 
-	__bch2_read(c, rbio, rbio->bio.bi_iter, inum, &failed,
-		    BCH_READ_RETRY_IF_STALE|
-		    BCH_READ_MAY_PROMOTE|
-		    BCH_READ_USER_MAPPED);
+	bch2_trans_run(c,
+		__bch2_read(trans, rbio, rbio->bio.bi_iter, inum, NULL, NULL,
+			    BCH_READ_retry_if_stale|
+			    BCH_READ_may_promote|
+			    BCH_READ_user_mapped));
+}
+
+static inline struct bch_read_bio *rbio_init_fragment(struct bio *bio,
+						      struct bch_read_bio *orig)
+{
+	struct bch_read_bio *rbio = to_rbio(bio);
+
+	rbio->c			= orig->c;
+	rbio->_state		= 0;
+	rbio->flags		= 0;
+	rbio->ret		= 0;
+	rbio->split		= true;
+	rbio->parent		= orig;
+	rbio->opts		= orig->opts;
+	return rbio;
 }
 
 static inline struct bch_read_bio *rbio_init(struct bio *bio,
-					     struct bch_io_opts opts)
+					     struct bch_fs *c,
+					     struct bch_io_opts opts,
+					     bio_end_io_t end_io)
 {
 	struct bch_read_bio *rbio = to_rbio(bio);
 
-	rbio->_state	= 0;
-	rbio->promote	= NULL;
-	rbio->opts	= opts;
+	rbio->start_time	= local_clock();
+	rbio->c			= c;
+	rbio->_state		= 0;
+	rbio->flags		= 0;
+	rbio->ret		= 0;
+	rbio->opts		= opts;
+	rbio->bio.bi_end_io	= end_io;
 	return rbio;
 }
 
diff --git a/fs/bcachefs/io_write.c b/fs/bcachefs/io_write.c
index 03892388832b..07b55839768e 100644
--- a/fs/bcachefs/io_write.c
+++ b/fs/bcachefs/io_write.c
@@ -34,6 +34,12 @@
 #include <linux/random.h>
 #include <linux/sched/mm.h>
 
+#ifdef CONFIG_BCACHEFS_DEBUG
+static unsigned bch2_write_corrupt_ratio;
+module_param_named(write_corrupt_ratio, bch2_write_corrupt_ratio, uint, 0644);
+MODULE_PARM_DESC(write_corrupt_ratio, "");
+#endif
+
 #ifndef CONFIG_BCACHEFS_NO_LATENCY_ACCT
 
 static inline void bch2_congested_acct(struct bch_dev *ca, u64 io_latency,
@@ -374,7 +380,7 @@ static int bch2_write_index_default(struct bch_write_op *op)
 			bch2_extent_update(trans, inum, &iter, sk.k,
 					&op->res,
 					op->new_i_size, &op->i_sectors_delta,
-					op->flags & BCH_WRITE_CHECK_ENOSPC);
+					op->flags & BCH_WRITE_check_enospc);
 		bch2_trans_iter_exit(trans, &iter);
 
 		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
@@ -396,29 +402,36 @@ static int bch2_write_index_default(struct bch_write_op *op)
 
 /* Writes */
 
-static void __bch2_write_op_error(struct printbuf *out, struct bch_write_op *op,
-				  u64 offset)
+void bch2_write_op_error(struct bch_write_op *op, u64 offset, const char *fmt, ...)
 {
-	bch2_inum_offset_err_msg(op->c, out,
-				 (subvol_inum) { op->subvol, op->pos.inode, },
-				 offset << 9);
-	prt_printf(out, "write error%s: ",
-		   op->flags & BCH_WRITE_MOVE ? "(internal move)" : "");
-}
+	struct printbuf buf = PRINTBUF;
 
-void bch2_write_op_error(struct printbuf *out, struct bch_write_op *op)
-{
-	__bch2_write_op_error(out, op, op->pos.offset);
-}
+	if (op->subvol) {
+		bch2_inum_offset_err_msg(op->c, &buf,
+					 (subvol_inum) { op->subvol, op->pos.inode, },
+					 offset << 9);
+	} else {
+		struct bpos pos = op->pos;
+		pos.offset = offset;
+		bch2_inum_snap_offset_err_msg(op->c, &buf, pos);
+	}
 
-static void bch2_write_op_error_trans(struct btree_trans *trans, struct printbuf *out,
-				      struct bch_write_op *op, u64 offset)
-{
-	bch2_inum_offset_err_msg_trans(trans, out,
-				       (subvol_inum) { op->subvol, op->pos.inode, },
-				       offset << 9);
-	prt_printf(out, "write error%s: ",
-		   op->flags & BCH_WRITE_MOVE ? "(internal move)" : "");
+	prt_str(&buf, "write error: ");
+
+	va_list args;
+	va_start(args, fmt);
+	prt_vprintf(&buf, fmt, args);
+	va_end(args);
+
+	if (op->flags & BCH_WRITE_move) {
+		struct data_update *u = container_of(op, struct data_update, op);
+
+		prt_printf(&buf, "\n  from internal move ");
+		bch2_bkey_val_to_text(&buf, op->c, bkey_i_to_s_c(u->k.k));
+	}
+
+	bch_err_ratelimited(op->c, "%s", buf.buf);
+	printbuf_exit(&buf);
 }
 
 void bch2_submit_wbio_replicas(struct bch_write_bio *wbio, struct bch_fs *c,
@@ -493,7 +506,7 @@ static void bch2_write_done(struct closure *cl)
 	bch2_time_stats_update(&c->times[BCH_TIME_data_write], op->start_time);
 	bch2_disk_reservation_put(c, &op->res);
 
-	if (!(op->flags & BCH_WRITE_MOVE))
+	if (!(op->flags & BCH_WRITE_move))
 		bch2_write_ref_put(c, BCH_WRITE_REF_write);
 	bch2_keylist_free(&op->insert_keys, op->inline_keys);
 
@@ -516,7 +529,7 @@ static noinline int bch2_write_drop_io_error_ptrs(struct bch_write_op *op)
 					    test_bit(ptr->dev, op->failed.d));
 
 			if (!bch2_bkey_nr_ptrs(bkey_i_to_s_c(src)))
-				return -EIO;
+				return -BCH_ERR_data_write_io;
 		}
 
 		if (dst != src)
@@ -539,7 +552,7 @@ static void __bch2_write_index(struct bch_write_op *op)
 	unsigned dev;
 	int ret = 0;
 
-	if (unlikely(op->flags & BCH_WRITE_IO_ERROR)) {
+	if (unlikely(op->flags & BCH_WRITE_io_error)) {
 		ret = bch2_write_drop_io_error_ptrs(op);
 		if (ret)
 			goto err;
@@ -548,7 +561,7 @@ static void __bch2_write_index(struct bch_write_op *op)
 	if (!bch2_keylist_empty(keys)) {
 		u64 sectors_start = keylist_sectors(keys);
 
-		ret = !(op->flags & BCH_WRITE_MOVE)
+		ret = !(op->flags & BCH_WRITE_move)
 			? bch2_write_index_default(op)
 			: bch2_data_update_index_update(op);
 
@@ -560,11 +573,8 @@ static void __bch2_write_index(struct bch_write_op *op)
 		if (unlikely(ret && !bch2_err_matches(ret, EROFS))) {
 			struct bkey_i *insert = bch2_keylist_front(&op->insert_keys);
 
-			struct printbuf buf = PRINTBUF;
-			__bch2_write_op_error(&buf, op, bkey_start_offset(&insert->k));
-			prt_printf(&buf, "btree update error: %s", bch2_err_str(ret));
-			bch_err_ratelimited(c, "%s", buf.buf);
-			printbuf_exit(&buf);
+			bch2_write_op_error(op, bkey_start_offset(&insert->k),
+					    "btree update error: %s", bch2_err_str(ret));
 		}
 
 		if (ret)
@@ -573,21 +583,29 @@ static void __bch2_write_index(struct bch_write_op *op)
 out:
 	/* If some a bucket wasn't written, we can't erasure code it: */
 	for_each_set_bit(dev, op->failed.d, BCH_SB_MEMBERS_MAX)
-		bch2_open_bucket_write_error(c, &op->open_buckets, dev);
+		bch2_open_bucket_write_error(c, &op->open_buckets, dev, -BCH_ERR_data_write_io);
 
 	bch2_open_buckets_put(c, &op->open_buckets);
 	return;
 err:
 	keys->top = keys->keys;
 	op->error = ret;
-	op->flags |= BCH_WRITE_SUBMITTED;
+	op->flags |= BCH_WRITE_submitted;
 	goto out;
 }
 
 static inline void __wp_update_state(struct write_point *wp, enum write_point_state state)
 {
 	if (state != wp->state) {
+		struct task_struct *p = current;
 		u64 now = ktime_get_ns();
+		u64 runtime = p->se.sum_exec_runtime +
+			(now - p->se.exec_start);
+
+		if (state == WRITE_POINT_runnable)
+			wp->last_runtime = runtime;
+		else if (wp->state == WRITE_POINT_runnable)
+			wp->time[WRITE_POINT_running] += runtime - wp->last_runtime;
 
 		if (wp->last_state_change &&
 		    time_after64(now, wp->last_state_change))
@@ -601,7 +619,7 @@ static inline void wp_update_state(struct write_point *wp, bool running)
 {
 	enum write_point_state state;
 
-	state = running			 ? WRITE_POINT_running :
+	state = running			 ? WRITE_POINT_runnable:
 		!list_empty(&wp->writes) ? WRITE_POINT_waiting_io
 					 : WRITE_POINT_stopped;
 
@@ -615,8 +633,8 @@ static CLOSURE_CALLBACK(bch2_write_index)
 	struct workqueue_struct *wq = index_update_wq(op);
 	unsigned long flags;
 
-	if ((op->flags & BCH_WRITE_SUBMITTED) &&
-	    (op->flags & BCH_WRITE_MOVE))
+	if ((op->flags & BCH_WRITE_submitted) &&
+	    (op->flags & BCH_WRITE_move))
 		bch2_bio_free_pages_pool(op->c, &op->wbio.bio);
 
 	spin_lock_irqsave(&wp->writes_lock, flags);
@@ -654,11 +672,11 @@ void bch2_write_point_do_index_updates(struct work_struct *work)
 		if (!op)
 			break;
 
-		op->flags |= BCH_WRITE_IN_WORKER;
+		op->flags |= BCH_WRITE_in_worker;
 
 		__bch2_write_index(op);
 
-		if (!(op->flags & BCH_WRITE_SUBMITTED))
+		if (!(op->flags & BCH_WRITE_submitted))
 			__bch2_write(op);
 		else
 			bch2_write_done(&op->cl);
@@ -676,13 +694,17 @@ static void bch2_write_endio(struct bio *bio)
 		? bch2_dev_have_ref(c, wbio->dev)
 		: NULL;
 
-	if (bch2_dev_inum_io_err_on(bio->bi_status, ca, BCH_MEMBER_ERROR_write,
+	bch2_account_io_completion(ca, BCH_MEMBER_ERROR_write,
+				   wbio->submit_time, !bio->bi_status);
+
+	if (bio->bi_status) {
+		bch_err_inum_offset_ratelimited(ca,
 				    op->pos.inode,
 				    wbio->inode_offset << 9,
 				    "data write error: %s",
-				    bch2_blk_status_to_str(bio->bi_status))) {
+				    bch2_blk_status_to_str(bio->bi_status));
 		set_bit(wbio->dev, op->failed.d);
-		op->flags |= BCH_WRITE_IO_ERROR;
+		op->flags |= BCH_WRITE_io_error;
 	}
 
 	if (wbio->nocow) {
@@ -692,10 +714,8 @@ static void bch2_write_endio(struct bio *bio)
 		set_bit(wbio->dev, op->devs_need_flush->d);
 	}
 
-	if (wbio->have_ioref) {
-		bch2_latency_acct(ca, wbio->submit_time, WRITE);
+	if (wbio->have_ioref)
 		percpu_ref_put(&ca->io_ref);
-	}
 
 	if (wbio->bounce)
 		bch2_bio_free_pages_pool(c, bio);
@@ -729,7 +749,7 @@ static void init_append_extent(struct bch_write_op *op,
 		bch2_extent_crc_append(&e->k_i, crc);
 
 	bch2_alloc_sectors_append_ptrs_inlined(op->c, wp, &e->k_i, crc.compressed_size,
-				       op->flags & BCH_WRITE_CACHED);
+				       op->flags & BCH_WRITE_cached);
 
 	bch2_keylist_push(&op->insert_keys);
 }
@@ -789,7 +809,6 @@ static int bch2_write_rechecksum(struct bch_fs *c,
 {
 	struct bio *bio = &op->wbio.bio;
 	struct bch_extent_crc_unpacked new_crc;
-	int ret;
 
 	/* bch2_rechecksum_bio() can't encrypt or decrypt data: */
 
@@ -797,10 +816,10 @@ static int bch2_write_rechecksum(struct bch_fs *c,
 	    bch2_csum_type_is_encryption(new_csum_type))
 		new_csum_type = op->crc.csum_type;
 
-	ret = bch2_rechecksum_bio(c, bio, op->version, op->crc,
-				  NULL, &new_crc,
-				  op->crc.offset, op->crc.live_size,
-				  new_csum_type);
+	int ret = bch2_rechecksum_bio(c, bio, op->version, op->crc,
+				      NULL, &new_crc,
+				      op->crc.offset, op->crc.live_size,
+				      new_csum_type);
 	if (ret)
 		return ret;
 
@@ -810,44 +829,12 @@ static int bch2_write_rechecksum(struct bch_fs *c,
 	return 0;
 }
 
-static int bch2_write_decrypt(struct bch_write_op *op)
-{
-	struct bch_fs *c = op->c;
-	struct nonce nonce = extent_nonce(op->version, op->crc);
-	struct bch_csum csum;
-	int ret;
-
-	if (!bch2_csum_type_is_encryption(op->crc.csum_type))
-		return 0;
-
-	/*
-	 * If we need to decrypt data in the write path, we'll no longer be able
-	 * to verify the existing checksum (poly1305 mac, in this case) after
-	 * it's decrypted - this is the last point we'll be able to reverify the
-	 * checksum:
-	 */
-	csum = bch2_checksum_bio(c, op->crc.csum_type, nonce, &op->wbio.bio);
-	if (bch2_crc_cmp(op->crc.csum, csum) && !c->opts.no_data_io)
-		return -EIO;
-
-	ret = bch2_encrypt_bio(c, op->crc.csum_type, nonce, &op->wbio.bio);
-	op->crc.csum_type = 0;
-	op->crc.csum = (struct bch_csum) { 0, 0 };
-	return ret;
-}
-
-static enum prep_encoded_ret {
-	PREP_ENCODED_OK,
-	PREP_ENCODED_ERR,
-	PREP_ENCODED_CHECKSUM_ERR,
-	PREP_ENCODED_DO_WRITE,
-} bch2_write_prep_encoded_data(struct bch_write_op *op, struct write_point *wp)
+static noinline int bch2_write_prep_encoded_data(struct bch_write_op *op, struct write_point *wp)
 {
 	struct bch_fs *c = op->c;
 	struct bio *bio = &op->wbio.bio;
-
-	if (!(op->flags & BCH_WRITE_DATA_ENCODED))
-		return PREP_ENCODED_OK;
+	struct bch_csum csum;
+	int ret = 0;
 
 	BUG_ON(bio_sectors(bio) != op->crc.compressed_size);
 
@@ -858,12 +845,13 @@ static enum prep_encoded_ret {
 	    (op->crc.compression_type == bch2_compression_opt_to_type(op->compression_opt) ||
 	     op->incompressible)) {
 		if (!crc_is_compressed(op->crc) &&
-		    op->csum_type != op->crc.csum_type &&
-		    bch2_write_rechecksum(c, op, op->csum_type) &&
-		    !c->opts.no_data_io)
-			return PREP_ENCODED_CHECKSUM_ERR;
+		    op->csum_type != op->crc.csum_type) {
+			ret = bch2_write_rechecksum(c, op, op->csum_type);
+			if (ret)
+				return ret;
+		}
 
-		return PREP_ENCODED_DO_WRITE;
+		return 1;
 	}
 
 	/*
@@ -871,20 +859,24 @@ static enum prep_encoded_ret {
 	 * is, we have to decompress it:
 	 */
 	if (crc_is_compressed(op->crc)) {
-		struct bch_csum csum;
-
-		if (bch2_write_decrypt(op))
-			return PREP_ENCODED_CHECKSUM_ERR;
-
 		/* Last point we can still verify checksum: */
-		csum = bch2_checksum_bio(c, op->crc.csum_type,
-					 extent_nonce(op->version, op->crc),
-					 bio);
+		struct nonce nonce = extent_nonce(op->version, op->crc);
+		csum = bch2_checksum_bio(c, op->crc.csum_type, nonce, bio);
 		if (bch2_crc_cmp(op->crc.csum, csum) && !c->opts.no_data_io)
-			return PREP_ENCODED_CHECKSUM_ERR;
+			goto csum_err;
+
+		if (bch2_csum_type_is_encryption(op->crc.csum_type)) {
+			ret = bch2_encrypt_bio(c, op->crc.csum_type, nonce, bio);
+			if (ret)
+				return ret;
+
+			op->crc.csum_type = 0;
+			op->crc.csum = (struct bch_csum) { 0, 0 };
+		}
 
-		if (bch2_bio_uncompress_inplace(op, bio))
-			return PREP_ENCODED_ERR;
+		ret = bch2_bio_uncompress_inplace(op, bio);
+		if (ret)
+			return ret;
 	}
 
 	/*
@@ -896,22 +888,44 @@ static enum prep_encoded_ret {
 	 * If the data is checksummed and we're only writing a subset,
 	 * rechecksum and adjust bio to point to currently live data:
 	 */
-	if ((op->crc.live_size != op->crc.uncompressed_size ||
-	     op->crc.csum_type != op->csum_type) &&
-	    bch2_write_rechecksum(c, op, op->csum_type) &&
-	    !c->opts.no_data_io)
-		return PREP_ENCODED_CHECKSUM_ERR;
+	if (op->crc.live_size != op->crc.uncompressed_size ||
+	    op->crc.csum_type != op->csum_type) {
+		ret = bch2_write_rechecksum(c, op, op->csum_type);
+		if (ret)
+			return ret;
+	}
 
 	/*
 	 * If we want to compress the data, it has to be decrypted:
 	 */
-	if ((op->compression_opt ||
-	     bch2_csum_type_is_encryption(op->crc.csum_type) !=
-	     bch2_csum_type_is_encryption(op->csum_type)) &&
-	    bch2_write_decrypt(op))
-		return PREP_ENCODED_CHECKSUM_ERR;
+	if (bch2_csum_type_is_encryption(op->crc.csum_type) &&
+	    (op->compression_opt || op->crc.csum_type != op->csum_type)) {
+		struct nonce nonce = extent_nonce(op->version, op->crc);
+		csum = bch2_checksum_bio(c, op->crc.csum_type, nonce, bio);
+		if (bch2_crc_cmp(op->crc.csum, csum) && !c->opts.no_data_io)
+			goto csum_err;
+
+		ret = bch2_encrypt_bio(c, op->crc.csum_type, nonce, bio);
+		if (ret)
+			return ret;
+
+		op->crc.csum_type = 0;
+		op->crc.csum = (struct bch_csum) { 0, 0 };
+	}
 
-	return PREP_ENCODED_OK;
+	return 0;
+csum_err:
+	bch2_write_op_error(op, op->pos.offset,
+		"error verifying existing checksum while moving existing data (memory corruption?)\n"
+		"  expected %0llx:%0llx got %0llx:%0llx type %s",
+		op->crc.csum.hi,
+		op->crc.csum.lo,
+		csum.hi,
+		csum.lo,
+		op->crc.csum_type < BCH_CSUM_NR
+		? __bch2_csum_types[op->crc.csum_type]
+		: "(unknown)");
+	return -BCH_ERR_data_write_csum;
 }
 
 static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
@@ -926,43 +940,51 @@ static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 	bool page_alloc_failed = false;
 	int ret, more = 0;
 
+	if (op->incompressible)
+		op->compression_opt = 0;
+
 	BUG_ON(!bio_sectors(src));
 
 	ec_buf = bch2_writepoint_ec_buf(c, wp);
 
-	switch (bch2_write_prep_encoded_data(op, wp)) {
-	case PREP_ENCODED_OK:
-		break;
-	case PREP_ENCODED_ERR:
-		ret = -EIO;
-		goto err;
-	case PREP_ENCODED_CHECKSUM_ERR:
-		goto csum_err;
-	case PREP_ENCODED_DO_WRITE:
-		/* XXX look for bug here */
-		if (ec_buf) {
-			dst = bch2_write_bio_alloc(c, wp, src,
-						   &page_alloc_failed,
-						   ec_buf);
-			bio_copy_data(dst, src);
-			bounce = true;
+	if (unlikely(op->flags & BCH_WRITE_data_encoded)) {
+		ret = bch2_write_prep_encoded_data(op, wp);
+		if (ret < 0)
+			goto err;
+		if (ret) {
+			if (ec_buf) {
+				dst = bch2_write_bio_alloc(c, wp, src,
+							   &page_alloc_failed,
+							   ec_buf);
+				bio_copy_data(dst, src);
+				bounce = true;
+			}
+			init_append_extent(op, wp, op->version, op->crc);
+			goto do_write;
 		}
-		init_append_extent(op, wp, op->version, op->crc);
-		goto do_write;
 	}
 
 	if (ec_buf ||
 	    op->compression_opt ||
 	    (op->csum_type &&
-	     !(op->flags & BCH_WRITE_PAGES_STABLE)) ||
+	     !(op->flags & BCH_WRITE_pages_stable)) ||
 	    (bch2_csum_type_is_encryption(op->csum_type) &&
-	     !(op->flags & BCH_WRITE_PAGES_OWNED))) {
+	     !(op->flags & BCH_WRITE_pages_owned))) {
 		dst = bch2_write_bio_alloc(c, wp, src,
 					   &page_alloc_failed,
 					   ec_buf);
 		bounce = true;
 	}
 
+#ifdef CONFIG_BCACHEFS_DEBUG
+	unsigned write_corrupt_ratio = READ_ONCE(bch2_write_corrupt_ratio);
+	if (!bounce && write_corrupt_ratio) {
+		dst = bch2_write_bio_alloc(c, wp, src,
+					   &page_alloc_failed,
+					   ec_buf);
+		bounce = true;
+	}
+#endif
 	saved_iter = dst->bi_iter;
 
 	do {
@@ -976,7 +998,7 @@ static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 			break;
 
 		BUG_ON(op->compression_opt &&
-		       (op->flags & BCH_WRITE_DATA_ENCODED) &&
+		       (op->flags & BCH_WRITE_data_encoded) &&
 		       bch2_csum_type_is_encryption(op->crc.csum_type));
 		BUG_ON(op->compression_opt && !bounce);
 
@@ -1014,7 +1036,7 @@ static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 			}
 		}
 
-		if ((op->flags & BCH_WRITE_DATA_ENCODED) &&
+		if ((op->flags & BCH_WRITE_data_encoded) &&
 		    !crc_is_compressed(crc) &&
 		    bch2_csum_type_is_encryption(op->crc.csum_type) ==
 		    bch2_csum_type_is_encryption(op->csum_type)) {
@@ -1032,12 +1054,13 @@ static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 			 * data can't be modified (by userspace) while it's in
 			 * flight.
 			 */
-			if (bch2_rechecksum_bio(c, src, version, op->crc,
+			ret = bch2_rechecksum_bio(c, src, version, op->crc,
 					&crc, &op->crc,
 					src_len >> 9,
 					bio_sectors(src) - (src_len >> 9),
-					op->csum_type))
-				goto csum_err;
+					op->csum_type);
+			if (ret)
+				goto err;
 			/*
 			 * rchecksum_bio sets compression_type on crc from op->crc,
 			 * this isn't always correct as sometimes we're changing
@@ -1046,13 +1069,13 @@ static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 			crc.compression_type = compression_type;
 			crc.nonce = nonce;
 		} else {
-			if ((op->flags & BCH_WRITE_DATA_ENCODED) &&
-			    bch2_rechecksum_bio(c, src, version, op->crc,
+			if ((op->flags & BCH_WRITE_data_encoded) &&
+			    (ret = bch2_rechecksum_bio(c, src, version, op->crc,
 					NULL, &op->crc,
 					src_len >> 9,
 					bio_sectors(src) - (src_len >> 9),
-					op->crc.csum_type))
-				goto csum_err;
+					op->crc.csum_type)))
+				goto err;
 
 			crc.compressed_size	= dst_len >> 9;
 			crc.uncompressed_size	= src_len >> 9;
@@ -1072,6 +1095,14 @@ static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 
 		init_append_extent(op, wp, version, crc);
 
+#ifdef CONFIG_BCACHEFS_DEBUG
+		if (write_corrupt_ratio) {
+			swap(dst->bi_iter.bi_size, dst_len);
+			bch2_maybe_corrupt_bio(dst, write_corrupt_ratio);
+			swap(dst->bi_iter.bi_size, dst_len);
+		}
+#endif
+
 		if (dst != src)
 			bio_advance(dst, dst_len);
 		bio_advance(src, src_len);
@@ -1103,16 +1134,6 @@ static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 do_write:
 	*_dst = dst;
 	return more;
-csum_err:
-	{
-		struct printbuf buf = PRINTBUF;
-		bch2_write_op_error(&buf, op);
-		prt_printf(&buf, "error verifying existing checksum while rewriting existing data (memory corruption?)");
-		bch_err_ratelimited(c, "%s", buf.buf);
-		printbuf_exit(&buf);
-	}
-
-	ret = -EIO;
 err:
 	if (to_wbio(dst)->bounce)
 		bch2_bio_free_pages_pool(c, dst);
@@ -1190,39 +1211,36 @@ static void bch2_nocow_write_convert_unwritten(struct bch_write_op *op)
 {
 	struct bch_fs *c = op->c;
 	struct btree_trans *trans = bch2_trans_get(c);
+	int ret = 0;
 
 	for_each_keylist_key(&op->insert_keys, orig) {
-		int ret = for_each_btree_key_max_commit(trans, iter, BTREE_ID_extents,
+		ret = for_each_btree_key_max_commit(trans, iter, BTREE_ID_extents,
 				     bkey_start_pos(&orig->k), orig->k.p,
 				     BTREE_ITER_intent, k,
 				     NULL, NULL, BCH_TRANS_COMMIT_no_enospc, ({
 			bch2_nocow_write_convert_one_unwritten(trans, &iter, orig, k, op->new_i_size);
 		}));
-
-		if (ret && !bch2_err_matches(ret, EROFS)) {
-			struct bkey_i *insert = bch2_keylist_front(&op->insert_keys);
-
-			struct printbuf buf = PRINTBUF;
-			bch2_write_op_error_trans(trans, &buf, op, bkey_start_offset(&insert->k));
-			prt_printf(&buf, "btree update error: %s", bch2_err_str(ret));
-			bch_err_ratelimited(c, "%s", buf.buf);
-			printbuf_exit(&buf);
-		}
-
-		if (ret) {
-			op->error = ret;
+		if (ret)
 			break;
-		}
 	}
 
 	bch2_trans_put(trans);
+
+	if (ret && !bch2_err_matches(ret, EROFS)) {
+		struct bkey_i *insert = bch2_keylist_front(&op->insert_keys);
+		bch2_write_op_error(op, bkey_start_offset(&insert->k),
+				    "btree update error: %s", bch2_err_str(ret));
+	}
+
+	if (ret)
+		op->error = ret;
 }
 
 static void __bch2_nocow_write_done(struct bch_write_op *op)
 {
-	if (unlikely(op->flags & BCH_WRITE_IO_ERROR)) {
-		op->error = -EIO;
-	} else if (unlikely(op->flags & BCH_WRITE_CONVERT_UNWRITTEN))
+	if (unlikely(op->flags & BCH_WRITE_io_error)) {
+		op->error = -BCH_ERR_data_write_io;
+	} else if (unlikely(op->flags & BCH_WRITE_convert_unwritten))
 		bch2_nocow_write_convert_unwritten(op);
 }
 
@@ -1251,7 +1269,7 @@ static void bch2_nocow_write(struct bch_write_op *op)
 	struct bucket_to_lock *stale_at;
 	int stale, ret;
 
-	if (op->flags & BCH_WRITE_MOVE)
+	if (op->flags & BCH_WRITE_move)
 		return;
 
 	darray_init(&buckets);
@@ -1309,7 +1327,7 @@ static void bch2_nocow_write(struct bch_write_op *op)
 						   }), GFP_KERNEL|__GFP_NOFAIL);
 
 			if (ptr->unwritten)
-				op->flags |= BCH_WRITE_CONVERT_UNWRITTEN;
+				op->flags |= BCH_WRITE_convert_unwritten;
 		}
 
 		/* Unlock before taking nocow locks, doing IO: */
@@ -1317,7 +1335,7 @@ static void bch2_nocow_write(struct bch_write_op *op)
 		bch2_trans_unlock(trans);
 
 		bch2_cut_front(op->pos, op->insert_keys.top);
-		if (op->flags & BCH_WRITE_CONVERT_UNWRITTEN)
+		if (op->flags & BCH_WRITE_convert_unwritten)
 			bch2_cut_back(POS(op->pos.inode, op->pos.offset + bio_sectors(bio)), op->insert_keys.top);
 
 		darray_for_each(buckets, i) {
@@ -1342,7 +1360,7 @@ static void bch2_nocow_write(struct bch_write_op *op)
 			wbio_init(bio)->put_bio = true;
 			bio->bi_opf = op->wbio.bio.bi_opf;
 		} else {
-			op->flags |= BCH_WRITE_SUBMITTED;
+			op->flags |= BCH_WRITE_submitted;
 		}
 
 		op->pos.offset += bio_sectors(bio);
@@ -1352,11 +1370,12 @@ static void bch2_nocow_write(struct bch_write_op *op)
 		bio->bi_private	= &op->cl;
 		bio->bi_opf |= REQ_OP_WRITE;
 		closure_get(&op->cl);
+
 		bch2_submit_wbio_replicas(to_wbio(bio), c, BCH_DATA_user,
 					  op->insert_keys.top, true);
 
 		bch2_keylist_push(&op->insert_keys);
-		if (op->flags & BCH_WRITE_SUBMITTED)
+		if (op->flags & BCH_WRITE_submitted)
 			break;
 		bch2_btree_iter_advance(&iter);
 	}
@@ -1370,21 +1389,18 @@ static void bch2_nocow_write(struct bch_write_op *op)
 	darray_exit(&buckets);
 
 	if (ret) {
-		struct printbuf buf = PRINTBUF;
-		bch2_write_op_error(&buf, op);
-		prt_printf(&buf, "%s(): btree lookup error: %s", __func__, bch2_err_str(ret));
-		bch_err_ratelimited(c, "%s", buf.buf);
-		printbuf_exit(&buf);
+		bch2_write_op_error(op, op->pos.offset,
+				    "%s(): btree lookup error: %s", __func__, bch2_err_str(ret));
 		op->error = ret;
-		op->flags |= BCH_WRITE_SUBMITTED;
+		op->flags |= BCH_WRITE_submitted;
 	}
 
 	/* fallback to cow write path? */
-	if (!(op->flags & BCH_WRITE_SUBMITTED)) {
+	if (!(op->flags & BCH_WRITE_submitted)) {
 		closure_sync(&op->cl);
 		__bch2_nocow_write_done(op);
 		op->insert_keys.top = op->insert_keys.keys;
-	} else if (op->flags & BCH_WRITE_SYNC) {
+	} else if (op->flags & BCH_WRITE_sync) {
 		closure_sync(&op->cl);
 		bch2_nocow_write_done(&op->cl.work);
 	} else {
@@ -1414,7 +1430,7 @@ static void bch2_nocow_write(struct bch_write_op *op)
 				    "pointer to invalid bucket in nocow path on device %llu\n  %s",
 				    stale_at->b.inode,
 				    (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
-		ret = -EIO;
+		ret = -BCH_ERR_data_write_invalid_ptr;
 	} else {
 		/* We can retry this: */
 		ret = -BCH_ERR_transaction_restart;
@@ -1436,7 +1452,7 @@ static void __bch2_write(struct bch_write_op *op)
 
 	if (unlikely(op->opts.nocow && c->opts.nocow_enabled)) {
 		bch2_nocow_write(op);
-		if (op->flags & BCH_WRITE_SUBMITTED)
+		if (op->flags & BCH_WRITE_submitted)
 			goto out_nofs_restore;
 	}
 again:
@@ -1466,7 +1482,7 @@ static void __bch2_write(struct bch_write_op *op)
 		ret = bch2_trans_run(c, lockrestart_do(trans,
 			bch2_alloc_sectors_start_trans(trans,
 				op->target,
-				op->opts.erasure_code && !(op->flags & BCH_WRITE_CACHED),
+				op->opts.erasure_code && !(op->flags & BCH_WRITE_cached),
 				op->write_point,
 				&op->devs_have,
 				op->nr_replicas,
@@ -1489,16 +1505,12 @@ static void __bch2_write(struct bch_write_op *op)
 		bch2_alloc_sectors_done_inlined(c, wp);
 err:
 		if (ret <= 0) {
-			op->flags |= BCH_WRITE_SUBMITTED;
+			op->flags |= BCH_WRITE_submitted;
 
 			if (unlikely(ret < 0)) {
-				if (!(op->flags & BCH_WRITE_ALLOC_NOWAIT)) {
-					struct printbuf buf = PRINTBUF;
-					bch2_write_op_error(&buf, op);
-					prt_printf(&buf, "%s(): %s", __func__, bch2_err_str(ret));
-					bch_err_ratelimited(c, "%s", buf.buf);
-					printbuf_exit(&buf);
-				}
+				if (!(op->flags & BCH_WRITE_alloc_nowait))
+					bch2_write_op_error(op, op->pos.offset,
+							    "%s(): %s", __func__, bch2_err_str(ret));
 				op->error = ret;
 				break;
 			}
@@ -1524,14 +1536,14 @@ static void __bch2_write(struct bch_write_op *op)
 	 * synchronously here if we weren't able to submit all of the IO at
 	 * once, as that signals backpressure to the caller.
 	 */
-	if ((op->flags & BCH_WRITE_SYNC) ||
-	    (!(op->flags & BCH_WRITE_SUBMITTED) &&
-	     !(op->flags & BCH_WRITE_IN_WORKER))) {
+	if ((op->flags & BCH_WRITE_sync) ||
+	    (!(op->flags & BCH_WRITE_submitted) &&
+	     !(op->flags & BCH_WRITE_in_worker))) {
 		bch2_wait_on_allocator(c, &op->cl);
 
 		__bch2_write_index(op);
 
-		if (!(op->flags & BCH_WRITE_SUBMITTED))
+		if (!(op->flags & BCH_WRITE_submitted))
 			goto again;
 		bch2_write_done(&op->cl);
 	} else {
@@ -1552,8 +1564,8 @@ static void bch2_write_data_inline(struct bch_write_op *op, unsigned data_len)
 
 	memset(&op->failed, 0, sizeof(op->failed));
 
-	op->flags |= BCH_WRITE_WROTE_DATA_INLINE;
-	op->flags |= BCH_WRITE_SUBMITTED;
+	op->flags |= BCH_WRITE_wrote_data_inline;
+	op->flags |= BCH_WRITE_submitted;
 
 	bch2_check_set_feature(op->c, BCH_FEATURE_inline_data);
 
@@ -1616,8 +1628,8 @@ CLOSURE_CALLBACK(bch2_write)
 	BUG_ON(!op->write_point.v);
 	BUG_ON(bkey_eq(op->pos, POS_MAX));
 
-	if (op->flags & BCH_WRITE_ONLY_SPECIFIED_DEVS)
-		op->flags |= BCH_WRITE_ALLOC_NOWAIT;
+	if (op->flags & BCH_WRITE_only_specified_devs)
+		op->flags |= BCH_WRITE_alloc_nowait;
 
 	op->nr_replicas_required = min_t(unsigned, op->nr_replicas_required, op->nr_replicas);
 	op->start_time = local_clock();
@@ -1625,11 +1637,8 @@ CLOSURE_CALLBACK(bch2_write)
 	wbio_init(bio)->put_bio = false;
 
 	if (unlikely(bio->bi_iter.bi_size & (c->opts.block_size - 1))) {
-		struct printbuf buf = PRINTBUF;
-		bch2_write_op_error(&buf, op);
-		prt_printf(&buf, "misaligned write");
-		printbuf_exit(&buf);
-		op->error = -EIO;
+		bch2_write_op_error(op, op->pos.offset, "misaligned write");
+		op->error = -BCH_ERR_data_write_misaligned;
 		goto err;
 	}
 
@@ -1638,13 +1647,14 @@ CLOSURE_CALLBACK(bch2_write)
 		goto err;
 	}
 
-	if (!(op->flags & BCH_WRITE_MOVE) &&
+	if (!(op->flags & BCH_WRITE_move) &&
 	    !bch2_write_ref_tryget(c, BCH_WRITE_REF_write)) {
 		op->error = -BCH_ERR_erofs_no_writes;
 		goto err;
 	}
 
-	this_cpu_add(c->counters[BCH_COUNTER_io_write], bio_sectors(bio));
+	if (!(op->flags & BCH_WRITE_move))
+		this_cpu_add(c->counters[BCH_COUNTER_io_write], bio_sectors(bio));
 	bch2_increment_clock(c, bio_sectors(bio), WRITE);
 
 	data_len = min_t(u64, bio->bi_iter.bi_size,
@@ -1675,20 +1685,26 @@ static const char * const bch2_write_flags[] = {
 
 void bch2_write_op_to_text(struct printbuf *out, struct bch_write_op *op)
 {
-	prt_str(out, "pos: ");
+	if (!out->nr_tabstops)
+		printbuf_tabstop_push(out, 32);
+
+	prt_printf(out, "pos:\t");
 	bch2_bpos_to_text(out, op->pos);
 	prt_newline(out);
 	printbuf_indent_add(out, 2);
 
-	prt_str(out, "started: ");
+	prt_printf(out, "started:\t");
 	bch2_pr_time_units(out, local_clock() - op->start_time);
 	prt_newline(out);
 
-	prt_str(out, "flags: ");
+	prt_printf(out, "flags:\t");
 	prt_bitflags(out, bch2_write_flags, op->flags);
 	prt_newline(out);
 
-	prt_printf(out, "ref: %u\n", closure_nr_remaining(&op->cl));
+	prt_printf(out, "nr_replicas:\t%u\n", op->nr_replicas);
+	prt_printf(out, "nr_replicas_required:\t%u\n", op->nr_replicas_required);
+
+	prt_printf(out, "ref:\t%u\n", closure_nr_remaining(&op->cl));
 
 	printbuf_indent_sub(out, 2);
 }
diff --git a/fs/bcachefs/io_write.h b/fs/bcachefs/io_write.h
index b4626013abc8..b8ab19a1e1da 100644
--- a/fs/bcachefs/io_write.h
+++ b/fs/bcachefs/io_write.h
@@ -11,33 +11,27 @@
 void bch2_bio_free_pages_pool(struct bch_fs *, struct bio *);
 void bch2_bio_alloc_pages_pool(struct bch_fs *, struct bio *, size_t);
 
-#ifndef CONFIG_BCACHEFS_NO_LATENCY_ACCT
-void bch2_latency_acct(struct bch_dev *, u64, int);
-#else
-static inline void bch2_latency_acct(struct bch_dev *ca, u64 submit_time, int rw) {}
-#endif
-
 void bch2_submit_wbio_replicas(struct bch_write_bio *, struct bch_fs *,
 			       enum bch_data_type, const struct bkey_i *, bool);
 
-void bch2_write_op_error(struct printbuf *out, struct bch_write_op *op);
+__printf(3, 4)
+void bch2_write_op_error(struct bch_write_op *op, u64, const char *, ...);
 
 #define BCH_WRITE_FLAGS()		\
-	x(ALLOC_NOWAIT)			\
-	x(CACHED)			\
-	x(DATA_ENCODED)			\
-	x(PAGES_STABLE)			\
-	x(PAGES_OWNED)			\
-	x(ONLY_SPECIFIED_DEVS)		\
-	x(WROTE_DATA_INLINE)		\
-	x(FROM_INTERNAL)		\
-	x(CHECK_ENOSPC)			\
-	x(SYNC)				\
-	x(MOVE)				\
-	x(IN_WORKER)			\
-	x(SUBMITTED)			\
-	x(IO_ERROR)			\
-	x(CONVERT_UNWRITTEN)
+	x(alloc_nowait)			\
+	x(cached)			\
+	x(data_encoded)			\
+	x(pages_stable)			\
+	x(pages_owned)			\
+	x(only_specified_devs)		\
+	x(wrote_data_inline)		\
+	x(check_enospc)			\
+	x(sync)				\
+	x(move)				\
+	x(in_worker)			\
+	x(submitted)			\
+	x(io_error)			\
+	x(convert_unwritten)
 
 enum __bch_write_flags {
 #define x(f)	__BCH_WRITE_##f,
diff --git a/fs/bcachefs/io_write_types.h b/fs/bcachefs/io_write_types.h
index 6e878a6f2f0b..3ef6df9145ef 100644
--- a/fs/bcachefs/io_write_types.h
+++ b/fs/bcachefs/io_write_types.h
@@ -64,7 +64,7 @@ struct bch_write_op {
 	struct bpos		pos;
 	struct bversion		version;
 
-	/* For BCH_WRITE_DATA_ENCODED: */
+	/* For BCH_WRITE_data_encoded: */
 	struct bch_extent_crc_unpacked crc;
 
 	struct write_point_specifier write_point;
diff --git a/fs/bcachefs/journal.c b/fs/bcachefs/journal.c
index 05b1250619ec..ecb97d435f6a 100644
--- a/fs/bcachefs/journal.c
+++ b/fs/bcachefs/journal.c
@@ -20,13 +20,6 @@
 #include "journal_seq_blacklist.h"
 #include "trace.h"
 
-static const char * const bch2_journal_errors[] = {
-#define x(n)	#n,
-	JOURNAL_ERRORS()
-#undef x
-	NULL
-};
-
 static inline bool journal_seq_unwritten(struct journal *j, u64 seq)
 {
 	return seq > j->seq_ondisk;
@@ -56,14 +49,20 @@ static void bch2_journal_buf_to_text(struct printbuf *out, struct journal *j, u6
 	prt_printf(out, "seq:\t%llu\n", seq);
 	printbuf_indent_add(out, 2);
 
-	prt_printf(out, "refcount:\t%u\n", journal_state_count(s, i));
+	if (!buf->write_started)
+		prt_printf(out, "refcount:\t%u\n", journal_state_count(s, i & JOURNAL_STATE_BUF_MASK));
 
-	prt_printf(out, "size:\t");
-	prt_human_readable_u64(out, vstruct_bytes(buf->data));
-	prt_newline(out);
+	struct closure *cl = &buf->io;
+	int r = atomic_read(&cl->remaining);
+	prt_printf(out, "io:\t%pS r %i\n", cl->fn, r & CLOSURE_REMAINING_MASK);
+
+	if (buf->data) {
+		prt_printf(out, "size:\t");
+		prt_human_readable_u64(out, vstruct_bytes(buf->data));
+		prt_newline(out);
+	}
 
-	prt_printf(out, "expires:\t");
-	prt_printf(out, "%li jiffies\n", buf->expires - jiffies);
+	prt_printf(out, "expires:\t%li jiffies\n", buf->expires - jiffies);
 
 	prt_printf(out, "flags:\t");
 	if (buf->noflush)
@@ -87,6 +86,9 @@ static void bch2_journal_buf_to_text(struct printbuf *out, struct journal *j, u6
 
 static void bch2_journal_bufs_to_text(struct printbuf *out, struct journal *j)
 {
+	lockdep_assert_held(&j->lock);
+	out->atomic++;
+
 	if (!out->nr_tabstops)
 		printbuf_tabstop_push(out, 24);
 
@@ -95,6 +97,8 @@ static void bch2_journal_bufs_to_text(struct printbuf *out, struct journal *j)
 	     seq++)
 		bch2_journal_buf_to_text(out, j, seq);
 	prt_printf(out, "last buf %s\n", journal_entry_is_open(j) ? "open" : "closed");
+
+	--out->atomic;
 }
 
 static inline struct journal_buf *
@@ -104,10 +108,8 @@ journal_seq_to_buf(struct journal *j, u64 seq)
 
 	EBUG_ON(seq > journal_cur_seq(j));
 
-	if (journal_seq_unwritten(j, seq)) {
+	if (journal_seq_unwritten(j, seq))
 		buf = j->buf + (seq & JOURNAL_BUF_MASK);
-		EBUG_ON(le64_to_cpu(buf->data->seq) != seq);
-	}
 	return buf;
 }
 
@@ -139,8 +141,10 @@ journal_error_check_stuck(struct journal *j, int error, unsigned flags)
 	bool stuck = false;
 	struct printbuf buf = PRINTBUF;
 
-	if (!(error == JOURNAL_ERR_journal_full ||
-	      error == JOURNAL_ERR_journal_pin_full) ||
+	buf.atomic++;
+
+	if (!(error == -BCH_ERR_journal_full ||
+	      error == -BCH_ERR_journal_pin_full) ||
 	    nr_unwritten_journal_entries(j) ||
 	    (flags & BCH_WATERMARK_MASK) != BCH_WATERMARK_reclaim)
 		return stuck;
@@ -167,9 +171,9 @@ journal_error_check_stuck(struct journal *j, int error, unsigned flags)
 	spin_unlock(&j->lock);
 
 	bch_err(c, "Journal stuck! Hava a pre-reservation but journal full (error %s)",
-		bch2_journal_errors[error]);
+		bch2_err_str(error));
 	bch2_journal_debug_to_text(&buf, j);
-	bch_err(c, "%s", buf.buf);
+	bch2_print_string_as_lines(KERN_ERR, buf.buf);
 
 	printbuf_reset(&buf);
 	bch2_journal_pins_to_text(&buf, j);
@@ -195,7 +199,8 @@ void bch2_journal_do_writes(struct journal *j)
 		if (w->write_started)
 			continue;
 
-		if (!journal_state_count(j->reservations, idx)) {
+		if (!journal_state_seq_count(j, j->reservations, seq)) {
+			j->seq_write_started = seq;
 			w->write_started = true;
 			closure_call(&w->io, bch2_journal_write, j->wq, NULL);
 		}
@@ -306,7 +311,7 @@ static void __journal_entry_close(struct journal *j, unsigned closed_val, bool t
 
 	bch2_journal_space_available(j);
 
-	__bch2_journal_buf_put(j, old.idx, le64_to_cpu(buf->data->seq));
+	__bch2_journal_buf_put(j, le64_to_cpu(buf->data->seq));
 }
 
 void bch2_journal_halt(struct journal *j)
@@ -377,29 +382,41 @@ static int journal_entry_open(struct journal *j)
 	BUG_ON(BCH_SB_CLEAN(c->disk_sb.sb));
 
 	if (j->blocked)
-		return JOURNAL_ERR_blocked;
+		return -BCH_ERR_journal_blocked;
 
 	if (j->cur_entry_error)
 		return j->cur_entry_error;
 
-	if (bch2_journal_error(j))
-		return JOURNAL_ERR_insufficient_devices; /* -EROFS */
+	int ret = bch2_journal_error(j);
+	if (unlikely(ret))
+		return ret;
 
 	if (!fifo_free(&j->pin))
-		return JOURNAL_ERR_journal_pin_full;
+		return -BCH_ERR_journal_pin_full;
 
 	if (nr_unwritten_journal_entries(j) == ARRAY_SIZE(j->buf))
-		return JOURNAL_ERR_max_in_flight;
+		return -BCH_ERR_journal_max_in_flight;
+
+	if (atomic64_read(&j->seq) - j->seq_write_started == JOURNAL_STATE_BUF_NR)
+		return -BCH_ERR_journal_max_open;
 
 	if (journal_cur_seq(j) >= JOURNAL_SEQ_MAX) {
 		bch_err(c, "cannot start: journal seq overflow");
 		if (bch2_fs_emergency_read_only_locked(c))
 			bch_err(c, "fatal error - emergency read only");
-		return JOURNAL_ERR_insufficient_devices; /* -EROFS */
+		return -BCH_ERR_journal_shutdown;
 	}
 
+	if (!j->free_buf && !buf->data)
+		return -BCH_ERR_journal_buf_enomem; /* will retry after write completion frees up a buf */
+
 	BUG_ON(!j->cur_entry_sectors);
 
+	if (!buf->data) {
+		swap(buf->data,		j->free_buf);
+		swap(buf->buf_size,	j->free_buf_size);
+	}
+
 	buf->expires		=
 		(journal_cur_seq(j) == j->flushed_seq_ondisk
 		 ? jiffies
@@ -415,7 +432,7 @@ static int journal_entry_open(struct journal *j)
 	u64s = clamp_t(int, u64s, 0, JOURNAL_ENTRY_CLOSED_VAL - 1);
 
 	if (u64s <= (ssize_t) j->early_journal_entries.nr)
-		return JOURNAL_ERR_journal_full;
+		return -BCH_ERR_journal_full;
 
 	if (fifo_empty(&j->pin) && j->reclaim_thread)
 		wake_up_process(j->reclaim_thread);
@@ -464,7 +481,7 @@ static int journal_entry_open(struct journal *j)
 
 		new.idx++;
 		BUG_ON(journal_state_count(new, new.idx));
-		BUG_ON(new.idx != (journal_cur_seq(j) & JOURNAL_BUF_MASK));
+		BUG_ON(new.idx != (journal_cur_seq(j) & JOURNAL_STATE_BUF_MASK));
 
 		journal_state_inc(&new);
 
@@ -514,6 +531,33 @@ static void journal_write_work(struct work_struct *work)
 	spin_unlock(&j->lock);
 }
 
+static void journal_buf_prealloc(struct journal *j)
+{
+	if (j->free_buf &&
+	    j->free_buf_size >= j->buf_size_want)
+		return;
+
+	unsigned buf_size = j->buf_size_want;
+
+	spin_unlock(&j->lock);
+	void *buf = kvmalloc(buf_size, GFP_NOFS);
+	spin_lock(&j->lock);
+
+	if (buf &&
+	    (!j->free_buf ||
+	     buf_size > j->free_buf_size)) {
+		swap(buf,	j->free_buf);
+		swap(buf_size,	j->free_buf_size);
+	}
+
+	if (unlikely(buf)) {
+		spin_unlock(&j->lock);
+		/* kvfree can sleep */
+		kvfree(buf);
+		spin_lock(&j->lock);
+	}
+}
+
 static int __journal_res_get(struct journal *j, struct journal_res *res,
 			     unsigned flags)
 {
@@ -525,25 +569,28 @@ static int __journal_res_get(struct journal *j, struct journal_res *res,
 	if (journal_res_get_fast(j, res, flags))
 		return 0;
 
-	if (bch2_journal_error(j))
-		return -BCH_ERR_erofs_journal_err;
+	ret = bch2_journal_error(j);
+	if (unlikely(ret))
+		return ret;
 
 	if (j->blocked)
-		return -BCH_ERR_journal_res_get_blocked;
+		return -BCH_ERR_journal_blocked;
 
 	if ((flags & BCH_WATERMARK_MASK) < j->watermark) {
-		ret = JOURNAL_ERR_journal_full;
+		ret = -BCH_ERR_journal_full;
 		can_discard = j->can_discard;
 		goto out;
 	}
 
 	if (nr_unwritten_journal_entries(j) == ARRAY_SIZE(j->buf) && !journal_entry_is_open(j)) {
-		ret = JOURNAL_ERR_max_in_flight;
+		ret = -BCH_ERR_journal_max_in_flight;
 		goto out;
 	}
 
 	spin_lock(&j->lock);
 
+	journal_buf_prealloc(j);
+
 	/*
 	 * Recheck after taking the lock, so we don't race with another thread
 	 * that just did journal_entry_open() and call bch2_journal_entry_close()
@@ -566,25 +613,48 @@ static int __journal_res_get(struct journal *j, struct journal_res *res,
 		j->buf_size_want = max(j->buf_size_want, buf->buf_size << 1);
 
 	__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL, false);
-	ret = journal_entry_open(j) ?: JOURNAL_ERR_retry;
+	ret = journal_entry_open(j) ?: -BCH_ERR_journal_retry_open;
 unlock:
 	can_discard = j->can_discard;
 	spin_unlock(&j->lock);
 out:
-	if (ret == JOURNAL_ERR_retry)
-		goto retry;
-	if (!ret)
+	if (likely(!ret))
 		return 0;
+	if (ret == -BCH_ERR_journal_retry_open)
+		goto retry;
 
 	if (journal_error_check_stuck(j, ret, flags))
-		ret = -BCH_ERR_journal_res_get_blocked;
+		ret = -BCH_ERR_journal_stuck;
+
+	if (ret == -BCH_ERR_journal_max_in_flight &&
+	    track_event_change(&c->times[BCH_TIME_blocked_journal_max_in_flight], true) &&
+	    trace_journal_entry_full_enabled()) {
+		struct printbuf buf = PRINTBUF;
+
+		bch2_printbuf_make_room(&buf, 4096);
+
+		spin_lock(&j->lock);
+		prt_printf(&buf, "seq %llu\n", journal_cur_seq(j));
+		bch2_journal_bufs_to_text(&buf, j);
+		spin_unlock(&j->lock);
 
-	if (ret == JOURNAL_ERR_max_in_flight &&
-	    track_event_change(&c->times[BCH_TIME_blocked_journal_max_in_flight], true)) {
+		trace_journal_entry_full(c, buf.buf);
+		printbuf_exit(&buf);
+		count_event(c, journal_entry_full);
+	}
 
+	if (ret == -BCH_ERR_journal_max_open &&
+	    track_event_change(&c->times[BCH_TIME_blocked_journal_max_open], true) &&
+	    trace_journal_entry_full_enabled()) {
 		struct printbuf buf = PRINTBUF;
+
+		bch2_printbuf_make_room(&buf, 4096);
+
+		spin_lock(&j->lock);
 		prt_printf(&buf, "seq %llu\n", journal_cur_seq(j));
 		bch2_journal_bufs_to_text(&buf, j);
+		spin_unlock(&j->lock);
+
 		trace_journal_entry_full(c, buf.buf);
 		printbuf_exit(&buf);
 		count_event(c, journal_entry_full);
@@ -594,8 +664,8 @@ static int __journal_res_get(struct journal *j, struct journal_res *res,
 	 * Journal is full - can't rely on reclaim from work item due to
 	 * freezing:
 	 */
-	if ((ret == JOURNAL_ERR_journal_full ||
-	     ret == JOURNAL_ERR_journal_pin_full) &&
+	if ((ret == -BCH_ERR_journal_full ||
+	     ret == -BCH_ERR_journal_pin_full) &&
 	    !(flags & JOURNAL_RES_GET_NONBLOCK)) {
 		if (can_discard) {
 			bch2_journal_do_discards(j);
@@ -608,9 +678,7 @@ static int __journal_res_get(struct journal *j, struct journal_res *res,
 		}
 	}
 
-	return ret == JOURNAL_ERR_insufficient_devices
-		? -BCH_ERR_erofs_journal_err
-		: -BCH_ERR_journal_res_get_blocked;
+	return ret;
 }
 
 static unsigned max_dev_latency(struct bch_fs *c)
@@ -640,7 +708,7 @@ int bch2_journal_res_get_slowpath(struct journal *j, struct journal_res *res,
 	int ret;
 
 	if (closure_wait_event_timeout(&j->async_wait,
-		   (ret = __journal_res_get(j, res, flags)) != -BCH_ERR_journal_res_get_blocked ||
+		   !bch2_err_matches(ret = __journal_res_get(j, res, flags), BCH_ERR_operation_blocked) ||
 		   (flags & JOURNAL_RES_GET_NONBLOCK),
 		   HZ))
 		return ret;
@@ -654,19 +722,19 @@ int bch2_journal_res_get_slowpath(struct journal *j, struct journal_res *res,
 	remaining_wait = max(0, remaining_wait - HZ);
 
 	if (closure_wait_event_timeout(&j->async_wait,
-		   (ret = __journal_res_get(j, res, flags)) != -BCH_ERR_journal_res_get_blocked ||
+		   !bch2_err_matches(ret = __journal_res_get(j, res, flags), BCH_ERR_operation_blocked) ||
 		   (flags & JOURNAL_RES_GET_NONBLOCK),
 		   remaining_wait))
 		return ret;
 
+	bch_err(c, "Journal stuck? Waited for 10 seconds, err %s", bch2_err_str(ret));
 	struct printbuf buf = PRINTBUF;
 	bch2_journal_debug_to_text(&buf, j);
-	bch_err(c, "Journal stuck? Waited for 10 seconds...\n%s",
-		buf.buf);
+	bch2_print_string_as_lines(KERN_ERR, buf.buf);
 	printbuf_exit(&buf);
 
 	closure_wait_event(&j->async_wait,
-		   (ret = __journal_res_get(j, res, flags)) != -BCH_ERR_journal_res_get_blocked ||
+		   !bch2_err_matches(ret = __journal_res_get(j, res, flags), BCH_ERR_operation_blocked) ||
 		   (flags & JOURNAL_RES_GET_NONBLOCK));
 	return ret;
 }
@@ -687,7 +755,6 @@ void bch2_journal_entry_res_resize(struct journal *j,
 		goto out;
 
 	j->cur_entry_u64s = max_t(int, 0, j->cur_entry_u64s - d);
-	smp_mb();
 	state = READ_ONCE(j->reservations);
 
 	if (state.cur_entry_offset < JOURNAL_ENTRY_CLOSED_VAL &&
@@ -907,7 +974,7 @@ int bch2_journal_meta(struct journal *j)
 	struct bch_fs *c = container_of(j, struct bch_fs, journal);
 
 	if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_journal))
-		return -EROFS;
+		return -BCH_ERR_erofs_no_writes;
 
 	int ret = __bch2_journal_meta(j);
 	bch2_write_ref_put(c, BCH_WRITE_REF_journal);
@@ -951,7 +1018,8 @@ static void __bch2_journal_block(struct journal *j)
 			new.cur_entry_offset = JOURNAL_ENTRY_BLOCKED_VAL;
 		} while (!atomic64_try_cmpxchg(&j->reservations.counter, &old.v, new.v));
 
-		journal_cur_buf(j)->data->u64s = cpu_to_le32(old.cur_entry_offset);
+		if (old.cur_entry_offset < JOURNAL_ENTRY_BLOCKED_VAL)
+			journal_cur_buf(j)->data->u64s = cpu_to_le32(old.cur_entry_offset);
 	}
 }
 
@@ -992,7 +1060,7 @@ static struct journal_buf *__bch2_next_write_buffer_flush_journal_buf(struct jou
 				*blocked = true;
 			}
 
-			ret = journal_state_count(s, idx) > open
+			ret = journal_state_count(s, idx & JOURNAL_STATE_BUF_MASK) > open
 				? ERR_PTR(-EAGAIN)
 				: buf;
 			break;
@@ -1349,6 +1417,7 @@ int bch2_fs_journal_start(struct journal *j, u64 cur_seq)
 	j->replay_journal_seq_end = cur_seq;
 	j->last_seq_ondisk	= last_seq;
 	j->flushed_seq_ondisk	= cur_seq - 1;
+	j->seq_write_started	= cur_seq - 1;
 	j->seq_ondisk		= cur_seq - 1;
 	j->pin.front		= last_seq;
 	j->pin.back		= cur_seq;
@@ -1389,8 +1458,7 @@ int bch2_fs_journal_start(struct journal *j, u64 cur_seq)
 	set_bit(JOURNAL_running, &j->flags);
 	j->last_flush_write = jiffies;
 
-	j->reservations.idx = j->reservations.unwritten_idx = journal_cur_seq(j);
-	j->reservations.unwritten_idx++;
+	j->reservations.idx = journal_cur_seq(j);
 
 	c->last_bucket_seq_cleanup = journal_cur_seq(j);
 
@@ -1443,7 +1511,7 @@ int bch2_dev_journal_init(struct bch_dev *ca, struct bch_sb *sb)
 	unsigned nr_bvecs = DIV_ROUND_UP(JOURNAL_ENTRY_SIZE_MAX, PAGE_SIZE);
 
 	for (unsigned i = 0; i < ARRAY_SIZE(ja->bio); i++) {
-		ja->bio[i] = kmalloc(struct_size(ja->bio[i], bio.bi_inline_vecs,
+		ja->bio[i] = kzalloc(struct_size(ja->bio[i], bio.bi_inline_vecs,
 				     nr_bvecs), GFP_KERNEL);
 		if (!ja->bio[i])
 			return -BCH_ERR_ENOMEM_dev_journal_init;
@@ -1482,6 +1550,7 @@ void bch2_fs_journal_exit(struct journal *j)
 
 	for (unsigned i = 0; i < ARRAY_SIZE(j->buf); i++)
 		kvfree(j->buf[i].data);
+	kvfree(j->free_buf);
 	free_fifo(&j->pin);
 }
 
@@ -1508,13 +1577,13 @@ int bch2_fs_journal_init(struct journal *j)
 	if (!(init_fifo(&j->pin, JOURNAL_PIN, GFP_KERNEL)))
 		return -BCH_ERR_ENOMEM_journal_pin_fifo;
 
-	for (unsigned i = 0; i < ARRAY_SIZE(j->buf); i++) {
-		j->buf[i].buf_size = JOURNAL_ENTRY_SIZE_MIN;
-		j->buf[i].data = kvmalloc(j->buf[i].buf_size, GFP_KERNEL);
-		if (!j->buf[i].data)
-			return -BCH_ERR_ENOMEM_journal_buf;
+	j->free_buf_size = j->buf_size_want = JOURNAL_ENTRY_SIZE_MIN;
+	j->free_buf = kvmalloc(j->free_buf_size, GFP_KERNEL);
+	if (!j->free_buf)
+		return -BCH_ERR_ENOMEM_journal_buf;
+
+	for (unsigned i = 0; i < ARRAY_SIZE(j->buf); i++)
 		j->buf[i].idx = i;
-	}
 
 	j->pin.front = j->pin.back = 1;
 
@@ -1564,6 +1633,7 @@ void __bch2_journal_debug_to_text(struct printbuf *out, struct journal *j)
 	prt_printf(out, "average write size:\t");
 	prt_human_readable_u64(out, nr_writes ? div64_u64(j->entry_bytes_written, nr_writes) : 0);
 	prt_newline(out);
+	prt_printf(out, "free buf:\t%u\n",			j->free_buf ? j->free_buf_size : 0);
 	prt_printf(out, "nr direct reclaim:\t%llu\n",		j->nr_direct_reclaim);
 	prt_printf(out, "nr background reclaim:\t%llu\n",	j->nr_background_reclaim);
 	prt_printf(out, "reclaim kicked:\t%u\n",		j->reclaim_kicked);
@@ -1571,7 +1641,7 @@ void __bch2_journal_debug_to_text(struct printbuf *out, struct journal *j)
 	       ? jiffies_to_msecs(j->next_reclaim - jiffies) : 0);
 	prt_printf(out, "blocked:\t%u\n",			j->blocked);
 	prt_printf(out, "current entry sectors:\t%u\n",		j->cur_entry_sectors);
-	prt_printf(out, "current entry error:\t%s\n",		bch2_journal_errors[j->cur_entry_error]);
+	prt_printf(out, "current entry error:\t%s\n",		bch2_err_str(j->cur_entry_error));
 	prt_printf(out, "current entry:\t");
 
 	switch (s.cur_entry_offset) {
diff --git a/fs/bcachefs/journal.h b/fs/bcachefs/journal.h
index 107f7f901cd9..47828771f9c2 100644
--- a/fs/bcachefs/journal.h
+++ b/fs/bcachefs/journal.h
@@ -121,11 +121,6 @@ static inline void journal_wake(struct journal *j)
 	closure_wake_up(&j->async_wait);
 }
 
-static inline struct journal_buf *journal_cur_buf(struct journal *j)
-{
-	return j->buf + j->reservations.idx;
-}
-
 /* Sequence number of oldest dirty journal entry */
 
 static inline u64 journal_last_seq(struct journal *j)
@@ -143,6 +138,15 @@ static inline u64 journal_last_unwritten_seq(struct journal *j)
 	return j->seq_ondisk + 1;
 }
 
+static inline struct journal_buf *journal_cur_buf(struct journal *j)
+{
+	unsigned idx = (journal_cur_seq(j) &
+			JOURNAL_BUF_MASK &
+			~JOURNAL_STATE_BUF_MASK) + j->reservations.idx;
+
+	return j->buf + idx;
+}
+
 static inline int journal_state_count(union journal_res_state s, int idx)
 {
 	switch (idx) {
@@ -154,6 +158,15 @@ static inline int journal_state_count(union journal_res_state s, int idx)
 	BUG();
 }
 
+static inline int journal_state_seq_count(struct journal *j,
+					  union journal_res_state s, u64 seq)
+{
+	if (journal_cur_seq(j) - seq < JOURNAL_STATE_BUF_NR)
+		return journal_state_count(s, seq & JOURNAL_STATE_BUF_MASK);
+	else
+		return 0;
+}
+
 static inline void journal_state_inc(union journal_res_state *s)
 {
 	s->buf0_count += s->idx == 0;
@@ -193,7 +206,7 @@ bch2_journal_add_entry_noreservation(struct journal_buf *buf, size_t u64s)
 static inline struct jset_entry *
 journal_res_entry(struct journal *j, struct journal_res *res)
 {
-	return vstruct_idx(j->buf[res->idx].data, res->offset);
+	return vstruct_idx(j->buf[res->seq & JOURNAL_BUF_MASK].data, res->offset);
 }
 
 static inline unsigned journal_entry_init(struct jset_entry *entry, unsigned type,
@@ -267,8 +280,9 @@ bool bch2_journal_entry_close(struct journal *);
 void bch2_journal_do_writes(struct journal *);
 void bch2_journal_buf_put_final(struct journal *, u64);
 
-static inline void __bch2_journal_buf_put(struct journal *j, unsigned idx, u64 seq)
+static inline void __bch2_journal_buf_put(struct journal *j, u64 seq)
 {
+	unsigned idx = seq & JOURNAL_STATE_BUF_MASK;
 	union journal_res_state s;
 
 	s = journal_state_buf_put(j, idx);
@@ -276,8 +290,9 @@ static inline void __bch2_journal_buf_put(struct journal *j, unsigned idx, u64 s
 		bch2_journal_buf_put_final(j, seq);
 }
 
-static inline void bch2_journal_buf_put(struct journal *j, unsigned idx, u64 seq)
+static inline void bch2_journal_buf_put(struct journal *j, u64 seq)
 {
+	unsigned idx = seq & JOURNAL_STATE_BUF_MASK;
 	union journal_res_state s;
 
 	s = journal_state_buf_put(j, idx);
@@ -306,7 +321,7 @@ static inline void bch2_journal_res_put(struct journal *j,
 				       BCH_JSET_ENTRY_btree_keys,
 				       0, 0, 0);
 
-	bch2_journal_buf_put(j, res->idx, res->seq);
+	bch2_journal_buf_put(j, res->seq);
 
 	res->ref = 0;
 }
@@ -335,8 +350,10 @@ static inline int journal_res_get_fast(struct journal *j,
 
 		/*
 		 * Check if there is still room in the current journal
-		 * entry:
+		 * entry, smp_rmb() guarantees that reads from reservations.counter
+		 * occur before accessing cur_entry_u64s:
 		 */
+		smp_rmb();
 		if (new.cur_entry_offset + res->u64s > j->cur_entry_u64s)
 			return 0;
 
@@ -361,9 +378,9 @@ static inline int journal_res_get_fast(struct journal *j,
 				       &old.v, new.v));
 
 	res->ref	= true;
-	res->idx	= old.idx;
 	res->offset	= old.cur_entry_offset;
-	res->seq	= le64_to_cpu(j->buf[old.idx].data->seq);
+	res->seq	= journal_cur_seq(j);
+	res->seq -= (res->seq - old.idx) & JOURNAL_STATE_BUF_MASK;
 	return 1;
 }
 
@@ -390,6 +407,7 @@ static inline int bch2_journal_res_get(struct journal *j, struct journal_res *re
 				    (flags & JOURNAL_RES_GET_NONBLOCK) != 0,
 				    NULL, _THIS_IP_);
 		EBUG_ON(!res->ref);
+		BUG_ON(!res->seq);
 	}
 	return 0;
 }
diff --git a/fs/bcachefs/journal_io.c b/fs/bcachefs/journal_io.c
index 11c39e0c34f4..4ed6137f0439 100644
--- a/fs/bcachefs/journal_io.c
+++ b/fs/bcachefs/journal_io.c
@@ -1041,13 +1041,19 @@ static int journal_read_bucket(struct bch_dev *ca,
 			bio->bi_iter.bi_sector = offset;
 			bch2_bio_map(bio, buf->data, sectors_read << 9);
 
+			u64 submit_time = local_clock();
 			ret = submit_bio_wait(bio);
 			kfree(bio);
 
-			if (bch2_dev_io_err_on(ret, ca, BCH_MEMBER_ERROR_read,
-					       "journal read error: sector %llu",
-					       offset) ||
-			    bch2_meta_read_fault("journal")) {
+			if (!ret && bch2_meta_read_fault("journal"))
+				ret = -BCH_ERR_EIO_fault_injected;
+
+			bch2_account_io_completion(ca, BCH_MEMBER_ERROR_read,
+						   submit_time, !ret);
+
+			if (ret) {
+				bch_err_dev_ratelimited(ca,
+					"journal read error: sector %llu", offset);
 				/*
 				 * We don't error out of the recovery process
 				 * here, since the relevant journal entry may be
@@ -1110,13 +1116,16 @@ static int journal_read_bucket(struct bch_dev *ca,
 		struct bch_csum csum;
 		csum_good = jset_csum_good(c, j, &csum);
 
-		if (bch2_dev_io_err_on(!csum_good, ca, BCH_MEMBER_ERROR_checksum,
-				       "%s",
-				       (printbuf_reset(&err),
-					prt_str(&err, "journal "),
-					bch2_csum_err_msg(&err, csum_type, j->csum, csum),
-					err.buf)))
+		bch2_account_io_completion(ca, BCH_MEMBER_ERROR_checksum, 0, csum_good);
+
+		if (!csum_good) {
+			bch_err_dev_ratelimited(ca, "%s",
+				(printbuf_reset(&err),
+				 prt_str(&err, "journal "),
+				 bch2_csum_err_msg(&err, csum_type, j->csum, csum),
+				 err.buf));
 			saw_bad = true;
+		}
 
 		ret = bch2_encrypt(c, JSET_CSUM_TYPE(j), journal_nonce(j),
 			     j->encrypted_start,
@@ -1515,7 +1524,7 @@ static void __journal_write_alloc(struct journal *j,
  * @j:		journal object
  * @w:		journal buf (entry to be written)
  *
- * Returns: 0 on success, or -EROFS on failure
+ * Returns: 0 on success, or -BCH_ERR_insufficient_devices on failure
  */
 static int journal_write_alloc(struct journal *j, struct journal_buf *w)
 {
@@ -1600,18 +1609,12 @@ static void journal_buf_realloc(struct journal *j, struct journal_buf *buf)
 	kvfree(new_buf);
 }
 
-static inline struct journal_buf *journal_last_unwritten_buf(struct journal *j)
-{
-	return j->buf + (journal_last_unwritten_seq(j) & JOURNAL_BUF_MASK);
-}
-
 static CLOSURE_CALLBACK(journal_write_done)
 {
 	closure_type(w, struct journal_buf, io);
 	struct journal *j = container_of(w, struct journal, buf[w->idx]);
 	struct bch_fs *c = container_of(j, struct bch_fs, journal);
 	struct bch_replicas_padded replicas;
-	union journal_res_state old, new;
 	u64 seq = le64_to_cpu(w->data->seq);
 	int err = 0;
 
@@ -1621,12 +1624,11 @@ static CLOSURE_CALLBACK(journal_write_done)
 
 	if (!w->devs_written.nr) {
 		bch_err(c, "unable to write journal to sufficient devices");
-		err = -EIO;
+		err = -BCH_ERR_journal_write_err;
 	} else {
 		bch2_devlist_to_replicas(&replicas.e, BCH_DATA_journal,
 					 w->devs_written);
-		if (bch2_mark_replicas(c, &replicas.e))
-			err = -EIO;
+		err = bch2_mark_replicas(c, &replicas.e);
 	}
 
 	if (err)
@@ -1641,7 +1643,23 @@ static CLOSURE_CALLBACK(journal_write_done)
 		j->err_seq	= seq;
 	w->write_done = true;
 
+	if (!j->free_buf || j->free_buf_size < w->buf_size) {
+		swap(j->free_buf,	w->data);
+		swap(j->free_buf_size,	w->buf_size);
+	}
+
+	if (w->data) {
+		void *buf = w->data;
+		w->data = NULL;
+		w->buf_size = 0;
+
+		spin_unlock(&j->lock);
+		kvfree(buf);
+		spin_lock(&j->lock);
+	}
+
 	bool completed = false;
+	bool do_discards = false;
 
 	for (seq = journal_last_unwritten_seq(j);
 	     seq <= journal_cur_seq(j);
@@ -1650,11 +1668,10 @@ static CLOSURE_CALLBACK(journal_write_done)
 		if (!w->write_done)
 			break;
 
-		if (!j->err_seq && !JSET_NO_FLUSH(w->data)) {
+		if (!j->err_seq && !w->noflush) {
 			j->flushed_seq_ondisk = seq;
 			j->last_seq_ondisk = w->last_seq;
 
-			bch2_do_discards(c);
 			closure_wake_up(&c->freelist_wait);
 			bch2_reset_alloc_cursors(c);
 		}
@@ -1671,16 +1688,6 @@ static CLOSURE_CALLBACK(journal_write_done)
 		if (j->watermark != BCH_WATERMARK_stripe)
 			journal_reclaim_kick(&c->journal);
 
-		old.v = atomic64_read(&j->reservations.counter);
-		do {
-			new.v = old.v;
-			BUG_ON(journal_state_count(new, new.unwritten_idx));
-			BUG_ON(new.unwritten_idx != (seq & JOURNAL_BUF_MASK));
-
-			new.unwritten_idx++;
-		} while (!atomic64_try_cmpxchg(&j->reservations.counter,
-					       &old.v, new.v));
-
 		closure_wake_up(&w->wait);
 		completed = true;
 	}
@@ -1695,7 +1702,7 @@ static CLOSURE_CALLBACK(journal_write_done)
 	}
 
 	if (journal_last_unwritten_seq(j) == journal_cur_seq(j) &&
-		   new.cur_entry_offset < JOURNAL_ENTRY_CLOSED_VAL) {
+	    j->reservations.cur_entry_offset < JOURNAL_ENTRY_CLOSED_VAL) {
 		struct journal_buf *buf = journal_cur_buf(j);
 		long delta = buf->expires - jiffies;
 
@@ -1715,6 +1722,9 @@ static CLOSURE_CALLBACK(journal_write_done)
 	 */
 	bch2_journal_do_writes(j);
 	spin_unlock(&j->lock);
+
+	if (do_discards)
+		bch2_do_discards(c);
 }
 
 static void journal_write_endio(struct bio *bio)
@@ -1724,13 +1734,16 @@ static void journal_write_endio(struct bio *bio)
 	struct journal *j = &ca->fs->journal;
 	struct journal_buf *w = j->buf + jbio->buf_idx;
 
-	if (bch2_dev_io_err_on(bio->bi_status, ca, BCH_MEMBER_ERROR_write,
+	bch2_account_io_completion(ca, BCH_MEMBER_ERROR_write,
+				   jbio->submit_time, !bio->bi_status);
+
+	if (bio->bi_status) {
+		bch_err_dev_ratelimited(ca,
 			       "error writing journal entry %llu: %s",
 			       le64_to_cpu(w->data->seq),
-			       bch2_blk_status_to_str(bio->bi_status)) ||
-	    bch2_meta_write_fault("journal")) {
-		unsigned long flags;
+			       bch2_blk_status_to_str(bio->bi_status));
 
+		unsigned long flags;
 		spin_lock_irqsave(&j->err_lock, flags);
 		bch2_dev_list_drop_dev(&w->devs_written, ca->dev_idx);
 		spin_unlock_irqrestore(&j->err_lock, flags);
@@ -1759,7 +1772,11 @@ static CLOSURE_CALLBACK(journal_write_submit)
 			     sectors);
 
 		struct journal_device *ja = &ca->journal;
-		struct bio *bio = &ja->bio[w->idx]->bio;
+		struct journal_bio *jbio = ja->bio[w->idx];
+		struct bio *bio = &jbio->bio;
+
+		jbio->submit_time	= local_clock();
+
 		bio_reset(bio, ca->disk_sb.bdev, REQ_OP_WRITE|REQ_SYNC|REQ_META);
 		bio->bi_iter.bi_sector	= ptr->offset;
 		bio->bi_end_io		= journal_write_endio;
@@ -1791,6 +1808,10 @@ static CLOSURE_CALLBACK(journal_write_preflush)
 	struct journal *j = container_of(w, struct journal, buf[w->idx]);
 	struct bch_fs *c = container_of(j, struct bch_fs, journal);
 
+	/*
+	 * Wait for previous journal writes to comelete; they won't necessarily
+	 * be flushed if they're still in flight
+	 */
 	if (j->seq_ondisk + 1 != le64_to_cpu(w->data->seq)) {
 		spin_lock(&j->lock);
 		if (j->seq_ondisk + 1 != le64_to_cpu(w->data->seq)) {
@@ -1984,7 +2005,7 @@ static int bch2_journal_write_pick_flush(struct journal *j, struct journal_buf *
 	 * write anything at all.
 	 */
 	if (error && test_bit(JOURNAL_need_flush_write, &j->flags))
-		return -EIO;
+		return error;
 
 	if (error ||
 	    w->noflush ||
diff --git a/fs/bcachefs/journal_reclaim.c b/fs/bcachefs/journal_reclaim.c
index d373cd181a7f..5d1547aa118a 100644
--- a/fs/bcachefs/journal_reclaim.c
+++ b/fs/bcachefs/journal_reclaim.c
@@ -226,7 +226,7 @@ void bch2_journal_space_available(struct journal *j)
 
 		bch_err(c, "%s", buf.buf);
 		printbuf_exit(&buf);
-		ret = JOURNAL_ERR_insufficient_devices;
+		ret = -BCH_ERR_insufficient_journal_devices;
 		goto out;
 	}
 
@@ -240,7 +240,7 @@ void bch2_journal_space_available(struct journal *j)
 	total		= j->space[journal_space_total].total;
 
 	if (!j->space[journal_space_discarded].next_entry)
-		ret = JOURNAL_ERR_journal_full;
+		ret = -BCH_ERR_journal_full;
 
 	if ((j->space[journal_space_clean_ondisk].next_entry <
 	     j->space[journal_space_clean_ondisk].total) &&
@@ -645,7 +645,6 @@ static u64 journal_seq_to_flush(struct journal *j)
  * @j:		journal object
  * @direct:	direct or background reclaim?
  * @kicked:	requested to run since we last ran?
- * Returns:	0 on success, or -EIO if the journal has been shutdown
  *
  * Background journal reclaim writes out btree nodes. It should be run
  * early enough so that we never completely run out of journal buckets.
@@ -685,10 +684,9 @@ static int __bch2_journal_reclaim(struct journal *j, bool direct, bool kicked)
 		if (kthread && kthread_should_stop())
 			break;
 
-		if (bch2_journal_error(j)) {
-			ret = -EIO;
+		ret = bch2_journal_error(j);
+		if (ret)
 			break;
-		}
 
 		bch2_journal_do_discards(j);
 
diff --git a/fs/bcachefs/journal_seq_blacklist.c b/fs/bcachefs/journal_seq_blacklist.c
index 1f25c111c54c..e463d2d95359 100644
--- a/fs/bcachefs/journal_seq_blacklist.c
+++ b/fs/bcachefs/journal_seq_blacklist.c
@@ -231,15 +231,14 @@ bool bch2_blacklist_entries_gc(struct bch_fs *c)
 	struct journal_seq_blacklist_table *t = c->journal_seq_blacklist_table;
 	BUG_ON(nr != t->nr);
 
-	unsigned i;
-	for (src = bl->start, i = t->nr == 0 ? 0 : eytzinger0_first(t->nr);
-	     src < bl->start + nr;
-	     src++, i = eytzinger0_next(i, nr)) {
+	src = bl->start;
+	eytzinger0_for_each(i, nr) {
 		BUG_ON(t->entries[i].start	!= le64_to_cpu(src->start));
 		BUG_ON(t->entries[i].end	!= le64_to_cpu(src->end));
 
 		if (t->entries[i].dirty || t->entries[i].end >= c->journal.oldest_seq_found_ondisk)
 			*dst++ = *src;
+		src++;
 	}
 
 	unsigned new_nr = dst - bl->start;
diff --git a/fs/bcachefs/journal_types.h b/fs/bcachefs/journal_types.h
index 1ef3a28ed6ab..8e0eba776b9d 100644
--- a/fs/bcachefs/journal_types.h
+++ b/fs/bcachefs/journal_types.h
@@ -12,7 +12,11 @@
 /* btree write buffer steals 8 bits for its own purposes: */
 #define JOURNAL_SEQ_MAX		((1ULL << 56) - 1)
 
-#define JOURNAL_BUF_BITS	2
+#define JOURNAL_STATE_BUF_BITS	2
+#define JOURNAL_STATE_BUF_NR	(1U << JOURNAL_STATE_BUF_BITS)
+#define JOURNAL_STATE_BUF_MASK	(JOURNAL_STATE_BUF_NR - 1)
+
+#define JOURNAL_BUF_BITS	4
 #define JOURNAL_BUF_NR		(1U << JOURNAL_BUF_BITS)
 #define JOURNAL_BUF_MASK	(JOURNAL_BUF_NR - 1)
 
@@ -82,7 +86,6 @@ struct journal_entry_pin {
 
 struct journal_res {
 	bool			ref;
-	u8			idx;
 	u16			u64s;
 	u32			offset;
 	u64			seq;
@@ -98,9 +101,8 @@ union journal_res_state {
 	};
 
 	struct {
-		u64		cur_entry_offset:20,
+		u64		cur_entry_offset:22,
 				idx:2,
-				unwritten_idx:2,
 				buf0_count:10,
 				buf1_count:10,
 				buf2_count:10,
@@ -110,13 +112,13 @@ union journal_res_state {
 
 /* bytes: */
 #define JOURNAL_ENTRY_SIZE_MIN		(64U << 10) /* 64k */
-#define JOURNAL_ENTRY_SIZE_MAX		(4U  << 20) /* 4M */
+#define JOURNAL_ENTRY_SIZE_MAX		(4U  << 22) /* 16M */
 
 /*
  * We stash some journal state as sentinal values in cur_entry_offset:
  * note - cur_entry_offset is in units of u64s
  */
-#define JOURNAL_ENTRY_OFFSET_MAX	((1U << 20) - 1)
+#define JOURNAL_ENTRY_OFFSET_MAX	((1U << 22) - 1)
 
 #define JOURNAL_ENTRY_BLOCKED_VAL	(JOURNAL_ENTRY_OFFSET_MAX - 2)
 #define JOURNAL_ENTRY_CLOSED_VAL	(JOURNAL_ENTRY_OFFSET_MAX - 1)
@@ -149,28 +151,12 @@ enum journal_flags {
 #undef x
 };
 
-/* Reasons we may fail to get a journal reservation: */
-#define JOURNAL_ERRORS()		\
-	x(ok)				\
-	x(retry)			\
-	x(blocked)			\
-	x(max_in_flight)		\
-	x(journal_full)			\
-	x(journal_pin_full)		\
-	x(journal_stuck)		\
-	x(insufficient_devices)
-
-enum journal_errors {
-#define x(n)	JOURNAL_ERR_##n,
-	JOURNAL_ERRORS()
-#undef x
-};
-
 typedef DARRAY(u64)		darray_u64;
 
 struct journal_bio {
 	struct bch_dev		*ca;
 	unsigned		buf_idx;
+	u64			submit_time;
 
 	struct bio		bio;
 };
@@ -199,7 +185,7 @@ struct journal {
 	 * 0, or -ENOSPC if waiting on journal reclaim, or -EROFS if
 	 * insufficient devices:
 	 */
-	enum journal_errors	cur_entry_error;
+	int			cur_entry_error;
 	unsigned		cur_entry_offset_if_blocked;
 
 	unsigned		buf_size_want;
@@ -220,6 +206,8 @@ struct journal {
 	 * other is possibly being written out.
 	 */
 	struct journal_buf	buf[JOURNAL_BUF_NR];
+	void			*free_buf;
+	unsigned		free_buf_size;
 
 	spinlock_t		lock;
 
@@ -237,6 +225,7 @@ struct journal {
 	/* Sequence number of most recent journal entry (last entry in @pin) */
 	atomic64_t		seq;
 
+	u64			seq_write_started;
 	/* seq, last_seq from the most recent journal entry successfully written */
 	u64			seq_ondisk;
 	u64			flushed_seq_ondisk;
diff --git a/fs/bcachefs/lru.c b/fs/bcachefs/lru.c
index ce794d55818f..a299d9ec8ee4 100644
--- a/fs/bcachefs/lru.c
+++ b/fs/bcachefs/lru.c
@@ -6,6 +6,7 @@
 #include "btree_iter.h"
 #include "btree_update.h"
 #include "btree_write_buffer.h"
+#include "ec.h"
 #include "error.h"
 #include "lru.h"
 #include "recovery.h"
@@ -59,9 +60,9 @@ int bch2_lru_set(struct btree_trans *trans, u16 lru_id, u64 dev_bucket, u64 time
 	return __bch2_lru_set(trans, lru_id, dev_bucket, time, KEY_TYPE_set);
 }
 
-int bch2_lru_change(struct btree_trans *trans,
-		    u16 lru_id, u64 dev_bucket,
-		    u64 old_time, u64 new_time)
+int __bch2_lru_change(struct btree_trans *trans,
+		      u16 lru_id, u64 dev_bucket,
+		      u64 old_time, u64 new_time)
 {
 	if (old_time == new_time)
 		return 0;
@@ -78,7 +79,9 @@ static const char * const bch2_lru_types[] = {
 };
 
 int bch2_lru_check_set(struct btree_trans *trans,
-		       u16 lru_id, u64 time,
+		       u16 lru_id,
+		       u64 dev_bucket,
+		       u64 time,
 		       struct bkey_s_c referring_k,
 		       struct bkey_buf *last_flushed)
 {
@@ -87,9 +90,7 @@ int bch2_lru_check_set(struct btree_trans *trans,
 	struct btree_iter lru_iter;
 	struct bkey_s_c lru_k =
 		bch2_bkey_get_iter(trans, &lru_iter, BTREE_ID_lru,
-				   lru_pos(lru_id,
-					   bucket_to_u64(referring_k.k->p),
-					   time), 0);
+				   lru_pos(lru_id, dev_bucket, time), 0);
 	int ret = bkey_err(lru_k);
 	if (ret)
 		return ret;
@@ -104,7 +105,7 @@ int bch2_lru_check_set(struct btree_trans *trans,
 			     "  %s",
 			     bch2_lru_types[lru_type(lru_k)],
 			     (bch2_bkey_val_to_text(&buf, c, referring_k), buf.buf))) {
-			ret = bch2_lru_set(trans, lru_id, bucket_to_u64(referring_k.k->p), time);
+			ret = bch2_lru_set(trans, lru_id, dev_bucket, time);
 			if (ret)
 				goto err;
 		}
@@ -116,49 +117,73 @@ int bch2_lru_check_set(struct btree_trans *trans,
 	return ret;
 }
 
+static struct bbpos lru_pos_to_bp(struct bkey_s_c lru_k)
+{
+	enum bch_lru_type type = lru_type(lru_k);
+
+	switch (type) {
+	case BCH_LRU_read:
+	case BCH_LRU_fragmentation:
+		return BBPOS(BTREE_ID_alloc, u64_to_bucket(lru_k.k->p.offset));
+	case BCH_LRU_stripes:
+		return BBPOS(BTREE_ID_stripes, POS(0, lru_k.k->p.offset));
+	default:
+		BUG();
+	}
+}
+
+static u64 bkey_lru_type_idx(struct bch_fs *c,
+			     enum bch_lru_type type,
+			     struct bkey_s_c k)
+{
+	struct bch_alloc_v4 a_convert;
+	const struct bch_alloc_v4 *a;
+
+	switch (type) {
+	case BCH_LRU_read:
+		a = bch2_alloc_to_v4(k, &a_convert);
+		return alloc_lru_idx_read(*a);
+	case BCH_LRU_fragmentation: {
+		a = bch2_alloc_to_v4(k, &a_convert);
+
+		rcu_read_lock();
+		struct bch_dev *ca = bch2_dev_rcu_noerror(c, k.k->p.inode);
+		u64 idx = ca
+			? alloc_lru_idx_fragmentation(*a, ca)
+			: 0;
+		rcu_read_unlock();
+		return idx;
+	}
+	case BCH_LRU_stripes:
+		return k.k->type == KEY_TYPE_stripe
+			? stripe_lru_pos(bkey_s_c_to_stripe(k).v)
+			: 0;
+	default:
+		BUG();
+	}
+}
+
 static int bch2_check_lru_key(struct btree_trans *trans,
 			      struct btree_iter *lru_iter,
 			      struct bkey_s_c lru_k,
 			      struct bkey_buf *last_flushed)
 {
 	struct bch_fs *c = trans->c;
-	struct btree_iter iter;
-	struct bkey_s_c k;
-	struct bch_alloc_v4 a_convert;
-	const struct bch_alloc_v4 *a;
 	struct printbuf buf1 = PRINTBUF;
 	struct printbuf buf2 = PRINTBUF;
-	enum bch_lru_type type = lru_type(lru_k);
-	struct bpos alloc_pos = u64_to_bucket(lru_k.k->p.offset);
-	u64 idx;
-	int ret;
-
-	struct bch_dev *ca = bch2_dev_bucket_tryget_noerror(c, alloc_pos);
 
-	if (fsck_err_on(!ca,
-			trans, lru_entry_to_invalid_bucket,
-			"lru key points to nonexistent device:bucket %llu:%llu",
-			alloc_pos.inode, alloc_pos.offset))
-		return bch2_btree_bit_mod_buffered(trans, BTREE_ID_lru, lru_iter->pos, false);
+	struct bbpos bp = lru_pos_to_bp(lru_k);
 
-	k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_alloc, alloc_pos, 0);
-	ret = bkey_err(k);
+	struct btree_iter iter;
+	struct bkey_s_c k = bch2_bkey_get_iter(trans, &iter, bp.btree, bp.pos, 0);
+	int ret = bkey_err(k);
 	if (ret)
 		goto err;
 
-	a = bch2_alloc_to_v4(k, &a_convert);
-
-	switch (type) {
-	case BCH_LRU_read:
-		idx = alloc_lru_idx_read(*a);
-		break;
-	case BCH_LRU_fragmentation:
-		idx = alloc_lru_idx_fragmentation(*a, ca);
-		break;
-	}
+	enum bch_lru_type type = lru_type(lru_k);
+	u64 idx = bkey_lru_type_idx(c, type, k);
 
-	if (lru_k.k->type != KEY_TYPE_set ||
-	    lru_pos_time(lru_k.k->p) != idx) {
+	if (lru_pos_time(lru_k.k->p) != idx) {
 		ret = bch2_btree_write_buffer_maybe_flush(trans, lru_k, last_flushed);
 		if (ret)
 			goto err;
@@ -176,7 +201,6 @@ static int bch2_check_lru_key(struct btree_trans *trans,
 err:
 fsck_err:
 	bch2_trans_iter_exit(trans, &iter);
-	bch2_dev_put(ca);
 	printbuf_exit(&buf2);
 	printbuf_exit(&buf1);
 	return ret;
diff --git a/fs/bcachefs/lru.h b/fs/bcachefs/lru.h
index f31a6cf1514c..8abd0aa2083a 100644
--- a/fs/bcachefs/lru.h
+++ b/fs/bcachefs/lru.h
@@ -28,9 +28,14 @@ static inline enum bch_lru_type lru_type(struct bkey_s_c l)
 {
 	u16 lru_id = l.k->p.inode >> 48;
 
-	if (lru_id == BCH_LRU_FRAGMENTATION_START)
+	switch (lru_id) {
+	case BCH_LRU_BUCKET_FRAGMENTATION:
 		return BCH_LRU_fragmentation;
-	return BCH_LRU_read;
+	case BCH_LRU_STRIPE_FRAGMENTATION:
+		return BCH_LRU_stripes;
+	default:
+		return BCH_LRU_read;
+	}
 }
 
 int bch2_lru_validate(struct bch_fs *, struct bkey_s_c, struct bkey_validate_context);
@@ -46,10 +51,19 @@ void bch2_lru_pos_to_text(struct printbuf *, struct bpos);
 
 int bch2_lru_del(struct btree_trans *, u16, u64, u64);
 int bch2_lru_set(struct btree_trans *, u16, u64, u64);
-int bch2_lru_change(struct btree_trans *, u16, u64, u64, u64);
+int __bch2_lru_change(struct btree_trans *, u16, u64, u64, u64);
+
+static inline int bch2_lru_change(struct btree_trans *trans,
+		      u16 lru_id, u64 dev_bucket,
+		      u64 old_time, u64 new_time)
+{
+	return old_time != new_time
+		? __bch2_lru_change(trans, lru_id, dev_bucket, old_time, new_time)
+		: 0;
+}
 
 struct bkey_buf;
-int bch2_lru_check_set(struct btree_trans *, u16, u64, struct bkey_s_c, struct bkey_buf *);
+int bch2_lru_check_set(struct btree_trans *, u16, u64, u64, struct bkey_s_c, struct bkey_buf *);
 
 int bch2_check_lrus(struct bch_fs *);
 
diff --git a/fs/bcachefs/lru_format.h b/fs/bcachefs/lru_format.h
index f372cb3b8cda..b7392ad8e41f 100644
--- a/fs/bcachefs/lru_format.h
+++ b/fs/bcachefs/lru_format.h
@@ -9,7 +9,8 @@ struct bch_lru {
 
 #define BCH_LRU_TYPES()		\
 	x(read)			\
-	x(fragmentation)
+	x(fragmentation)	\
+	x(stripes)
 
 enum bch_lru_type {
 #define x(n) BCH_LRU_##n,
@@ -17,7 +18,8 @@ enum bch_lru_type {
 #undef x
 };
 
-#define BCH_LRU_FRAGMENTATION_START	((1U << 16) - 1)
+#define BCH_LRU_BUCKET_FRAGMENTATION	((1U << 16) - 1)
+#define BCH_LRU_STRIPE_FRAGMENTATION	((1U << 16) - 2)
 
 #define LRU_TIME_BITS			48
 #define LRU_TIME_MAX			((1ULL << LRU_TIME_BITS) - 1)
diff --git a/fs/bcachefs/migrate.c b/fs/bcachefs/migrate.c
index ddc187fb693d..57ad662871ba 100644
--- a/fs/bcachefs/migrate.c
+++ b/fs/bcachefs/migrate.c
@@ -15,6 +15,7 @@
 #include "keylist.h"
 #include "migrate.h"
 #include "move.h"
+#include "progress.h"
 #include "replicas.h"
 #include "super-io.h"
 
@@ -76,7 +77,9 @@ static int bch2_dev_usrdata_drop_key(struct btree_trans *trans,
 	return 0;
 }
 
-static int bch2_dev_usrdata_drop(struct bch_fs *c, unsigned dev_idx, int flags)
+static int bch2_dev_usrdata_drop(struct bch_fs *c,
+				 struct progress_indicator_state *progress,
+				 unsigned dev_idx, int flags)
 {
 	struct btree_trans *trans = bch2_trans_get(c);
 	enum btree_id id;
@@ -88,8 +91,10 @@ static int bch2_dev_usrdata_drop(struct bch_fs *c, unsigned dev_idx, int flags)
 
 		ret = for_each_btree_key_commit(trans, iter, id, POS_MIN,
 				BTREE_ITER_prefetch|BTREE_ITER_all_snapshots, k,
-				NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
-			bch2_dev_usrdata_drop_key(trans, &iter, k, dev_idx, flags));
+				NULL, NULL, BCH_TRANS_COMMIT_no_enospc, ({
+			bch2_progress_update_iter(trans, progress, &iter, "dropping user data");
+			bch2_dev_usrdata_drop_key(trans, &iter, k, dev_idx, flags);
+		}));
 		if (ret)
 			break;
 	}
@@ -99,7 +104,9 @@ static int bch2_dev_usrdata_drop(struct bch_fs *c, unsigned dev_idx, int flags)
 	return ret;
 }
 
-static int bch2_dev_metadata_drop(struct bch_fs *c, unsigned dev_idx, int flags)
+static int bch2_dev_metadata_drop(struct bch_fs *c,
+				  struct progress_indicator_state *progress,
+				  unsigned dev_idx, int flags)
 {
 	struct btree_trans *trans;
 	struct btree_iter iter;
@@ -125,6 +132,8 @@ static int bch2_dev_metadata_drop(struct bch_fs *c, unsigned dev_idx, int flags)
 		while (bch2_trans_begin(trans),
 		       (b = bch2_btree_iter_peek_node(&iter)) &&
 		       !(ret = PTR_ERR_OR_ZERO(b))) {
+			bch2_progress_update_iter(trans, progress, &iter, "dropping metadata");
+
 			if (!bch2_bkey_has_device_c(bkey_i_to_s_c(&b->key), dev_idx))
 				goto next;
 
@@ -169,6 +178,11 @@ static int bch2_dev_metadata_drop(struct bch_fs *c, unsigned dev_idx, int flags)
 
 int bch2_dev_data_drop(struct bch_fs *c, unsigned dev_idx, int flags)
 {
-	return bch2_dev_usrdata_drop(c, dev_idx, flags) ?:
-		bch2_dev_metadata_drop(c, dev_idx, flags);
+	struct progress_indicator_state progress;
+	bch2_progress_init(&progress, c,
+			   BIT_ULL(BTREE_ID_extents)|
+			   BIT_ULL(BTREE_ID_reflink));
+
+	return bch2_dev_usrdata_drop(c, &progress, dev_idx, flags) ?:
+		bch2_dev_metadata_drop(c, &progress, dev_idx, flags);
 }
diff --git a/fs/bcachefs/move.c b/fs/bcachefs/move.c
index 160b4374160a..66d1c055a2e3 100644
--- a/fs/bcachefs/move.c
+++ b/fs/bcachefs/move.c
@@ -38,28 +38,28 @@ const char * const bch2_data_ops_strs[] = {
 	NULL
 };
 
-static void trace_move_extent2(struct bch_fs *c, struct bkey_s_c k,
+static void trace_io_move2(struct bch_fs *c, struct bkey_s_c k,
 			       struct bch_io_opts *io_opts,
 			       struct data_update_opts *data_opts)
 {
-	if (trace_move_extent_enabled()) {
+	if (trace_io_move_enabled()) {
 		struct printbuf buf = PRINTBUF;
 
 		bch2_bkey_val_to_text(&buf, c, k);
 		prt_newline(&buf);
 		bch2_data_update_opts_to_text(&buf, c, io_opts, data_opts);
-		trace_move_extent(c, buf.buf);
+		trace_io_move(c, buf.buf);
 		printbuf_exit(&buf);
 	}
 }
 
-static void trace_move_extent_read2(struct bch_fs *c, struct bkey_s_c k)
+static void trace_io_move_read2(struct bch_fs *c, struct bkey_s_c k)
 {
-	if (trace_move_extent_read_enabled()) {
+	if (trace_io_move_read_enabled()) {
 		struct printbuf buf = PRINTBUF;
 
 		bch2_bkey_val_to_text(&buf, c, k);
-		trace_move_extent_read(c, buf.buf);
+		trace_io_move_read(c, buf.buf);
 		printbuf_exit(&buf);
 	}
 }
@@ -74,11 +74,7 @@ struct moving_io {
 	unsigned			read_sectors;
 	unsigned			write_sectors;
 
-	struct bch_read_bio		rbio;
-
 	struct data_update		write;
-	/* Must be last since it is variable size */
-	struct bio_vec			bi_inline_vecs[];
 };
 
 static void move_free(struct moving_io *io)
@@ -88,43 +84,86 @@ static void move_free(struct moving_io *io)
 	if (io->b)
 		atomic_dec(&io->b->count);
 
-	bch2_data_update_exit(&io->write);
-
 	mutex_lock(&ctxt->lock);
 	list_del(&io->io_list);
 	wake_up(&ctxt->wait);
 	mutex_unlock(&ctxt->lock);
 
+	if (!io->write.data_opts.scrub) {
+		bch2_data_update_exit(&io->write);
+	} else {
+		bch2_bio_free_pages_pool(io->write.op.c, &io->write.op.wbio.bio);
+		kfree(io->write.bvecs);
+	}
 	kfree(io);
 }
 
 static void move_write_done(struct bch_write_op *op)
 {
 	struct moving_io *io = container_of(op, struct moving_io, write.op);
+	struct bch_fs *c = op->c;
 	struct moving_context *ctxt = io->write.ctxt;
 
-	if (io->write.op.error)
+	if (op->error) {
+		if (trace_io_move_write_fail_enabled()) {
+			struct printbuf buf = PRINTBUF;
+
+			bch2_write_op_to_text(&buf, op);
+			prt_printf(&buf, "ret\t%s\n", bch2_err_str(op->error));
+			trace_io_move_write_fail(c, buf.buf);
+			printbuf_exit(&buf);
+		}
+		this_cpu_inc(c->counters[BCH_COUNTER_io_move_write_fail]);
+
 		ctxt->write_error = true;
+	}
 
-	atomic_sub(io->write_sectors, &io->write.ctxt->write_sectors);
-	atomic_dec(&io->write.ctxt->write_ios);
+	atomic_sub(io->write_sectors, &ctxt->write_sectors);
+	atomic_dec(&ctxt->write_ios);
 	move_free(io);
 	closure_put(&ctxt->cl);
 }
 
 static void move_write(struct moving_io *io)
 {
-	if (unlikely(io->rbio.bio.bi_status || io->rbio.hole)) {
+	struct bch_fs *c = io->write.op.c;
+	struct moving_context *ctxt = io->write.ctxt;
+	struct bch_read_bio *rbio = &io->write.rbio;
+
+	if (ctxt->stats) {
+		if (rbio->bio.bi_status)
+			atomic64_add(io->write.rbio.bvec_iter.bi_size >> 9,
+				     &ctxt->stats->sectors_error_uncorrected);
+		else if (rbio->saw_error)
+			atomic64_add(io->write.rbio.bvec_iter.bi_size >> 9,
+				     &ctxt->stats->sectors_error_corrected);
+	}
+
+	/*
+	 * If the extent has been bitrotted, we're going to have to give it a
+	 * new checksum in order to move it - but the poison bit will ensure
+	 * that userspace still gets the appropriate error.
+	 */
+	if (unlikely(rbio->ret == -BCH_ERR_data_read_csum_err &&
+		     (bch2_bkey_extent_flags(bkey_i_to_s_c(io->write.k.k)) & BIT_ULL(BCH_EXTENT_FLAG_poisoned)))) {
+		struct bch_extent_crc_unpacked crc = rbio->pick.crc;
+		struct nonce nonce = extent_nonce(rbio->version, crc);
+
+		rbio->pick.crc.csum	= bch2_checksum_bio(c, rbio->pick.crc.csum_type,
+							    nonce, &rbio->bio);
+		rbio->ret		= 0;
+	}
+
+	if (unlikely(rbio->ret || io->write.data_opts.scrub)) {
 		move_free(io);
 		return;
 	}
 
-	if (trace_move_extent_write_enabled()) {
-		struct bch_fs *c = io->write.op.c;
+	if (trace_io_move_write_enabled()) {
 		struct printbuf buf = PRINTBUF;
 
 		bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(io->write.k.k));
-		trace_move_extent_write(c, buf.buf);
+		trace_io_move_write(c, buf.buf);
 		printbuf_exit(&buf);
 	}
 
@@ -132,7 +171,7 @@ static void move_write(struct moving_io *io)
 	atomic_add(io->write_sectors, &io->write.ctxt->write_sectors);
 	atomic_inc(&io->write.ctxt->write_ios);
 
-	bch2_data_update_read_done(&io->write, io->rbio.pick.crc);
+	bch2_data_update_read_done(&io->write);
 }
 
 struct moving_io *bch2_moving_ctxt_next_pending_write(struct moving_context *ctxt)
@@ -145,7 +184,7 @@ struct moving_io *bch2_moving_ctxt_next_pending_write(struct moving_context *ctx
 
 static void move_read_endio(struct bio *bio)
 {
-	struct moving_io *io = container_of(bio, struct moving_io, rbio.bio);
+	struct moving_io *io = container_of(bio, struct moving_io, write.rbio.bio);
 	struct moving_context *ctxt = io->write.ctxt;
 
 	atomic_sub(io->read_sectors, &ctxt->read_sectors);
@@ -258,14 +297,10 @@ int bch2_move_extent(struct moving_context *ctxt,
 {
 	struct btree_trans *trans = ctxt->trans;
 	struct bch_fs *c = trans->c;
-	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
-	struct moving_io *io;
-	const union bch_extent_entry *entry;
-	struct extent_ptr_decoded p;
-	unsigned sectors = k.k->size, pages;
 	int ret = -ENOMEM;
 
-	trace_move_extent2(c, k, &io_opts, &data_opts);
+	trace_io_move2(c, k, &io_opts, &data_opts);
+	this_cpu_add(c->counters[BCH_COUNTER_io_move], k.k->size);
 
 	if (ctxt->stats)
 		ctxt->stats->pos = BBPOS(iter->btree_id, iter->pos);
@@ -273,7 +308,8 @@ int bch2_move_extent(struct moving_context *ctxt,
 	bch2_data_update_opts_normalize(k, &data_opts);
 
 	if (!data_opts.rewrite_ptrs &&
-	    !data_opts.extra_replicas) {
+	    !data_opts.extra_replicas &&
+	    !data_opts.scrub) {
 		if (data_opts.kill_ptrs)
 			return bch2_extent_drop_ptrs(trans, iter, k, &io_opts, &data_opts);
 		return 0;
@@ -285,13 +321,7 @@ int bch2_move_extent(struct moving_context *ctxt,
 	 */
 	bch2_trans_unlock(trans);
 
-	/* write path might have to decompress data: */
-	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
-		sectors = max_t(unsigned, sectors, p.crc.uncompressed_size);
-
-	pages = DIV_ROUND_UP(sectors, PAGE_SECTORS);
-	io = kzalloc(sizeof(struct moving_io) +
-		     sizeof(struct bio_vec) * pages, GFP_KERNEL);
+	struct moving_io *io = kzalloc(sizeof(struct moving_io), GFP_KERNEL);
 	if (!io)
 		goto err;
 
@@ -300,31 +330,27 @@ int bch2_move_extent(struct moving_context *ctxt,
 	io->read_sectors	= k.k->size;
 	io->write_sectors	= k.k->size;
 
-	bio_init(&io->write.op.wbio.bio, NULL, io->bi_inline_vecs, pages, 0);
-	io->write.op.wbio.bio.bi_ioprio =
-		     IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0);
-
-	if (bch2_bio_alloc_pages(&io->write.op.wbio.bio, sectors << 9,
-				 GFP_KERNEL))
-		goto err_free;
+	if (!data_opts.scrub) {
+		ret = bch2_data_update_init(trans, iter, ctxt, &io->write, ctxt->wp,
+					    &io_opts, data_opts, iter->btree_id, k);
+		if (ret)
+			goto err_free;
 
-	io->rbio.c		= c;
-	io->rbio.opts		= io_opts;
-	bio_init(&io->rbio.bio, NULL, io->bi_inline_vecs, pages, 0);
-	io->rbio.bio.bi_vcnt = pages;
-	io->rbio.bio.bi_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0);
-	io->rbio.bio.bi_iter.bi_size = sectors << 9;
+		io->write.op.end_io	= move_write_done;
+	} else {
+		bch2_bkey_buf_init(&io->write.k);
+		bch2_bkey_buf_reassemble(&io->write.k, c, k);
 
-	io->rbio.bio.bi_opf		= REQ_OP_READ;
-	io->rbio.bio.bi_iter.bi_sector	= bkey_start_offset(k.k);
-	io->rbio.bio.bi_end_io		= move_read_endio;
+		io->write.op.c		= c;
+		io->write.data_opts	= data_opts;
 
-	ret = bch2_data_update_init(trans, iter, ctxt, &io->write, ctxt->wp,
-				    io_opts, data_opts, iter->btree_id, k);
-	if (ret)
-		goto err_free_pages;
+		ret = bch2_data_update_bios_init(&io->write, c, &io_opts);
+		if (ret)
+			goto err_free;
+	}
 
-	io->write.op.end_io = move_write_done;
+	io->write.rbio.bio.bi_end_io = move_read_endio;
+	io->write.rbio.bio.bi_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0);
 
 	if (ctxt->rate)
 		bch2_ratelimit_increment(ctxt->rate, k.k->size);
@@ -339,9 +365,7 @@ int bch2_move_extent(struct moving_context *ctxt,
 		atomic_inc(&io->b->count);
 	}
 
-	this_cpu_add(c->counters[BCH_COUNTER_io_move], k.k->size);
-	this_cpu_add(c->counters[BCH_COUNTER_move_extent_read], k.k->size);
-	trace_move_extent_read2(c, k);
+	trace_io_move_read2(c, k);
 
 	mutex_lock(&ctxt->lock);
 	atomic_add(io->read_sectors, &ctxt->read_sectors);
@@ -356,33 +380,33 @@ int bch2_move_extent(struct moving_context *ctxt,
 	 * ctxt when doing wakeup
 	 */
 	closure_get(&ctxt->cl);
-	bch2_read_extent(trans, &io->rbio,
-			 bkey_start_pos(k.k),
-			 iter->btree_id, k, 0,
-			 BCH_READ_NODECODE|
-			 BCH_READ_LAST_FRAGMENT);
+	__bch2_read_extent(trans, &io->write.rbio,
+			   io->write.rbio.bio.bi_iter,
+			   bkey_start_pos(k.k),
+			   iter->btree_id, k, 0,
+			   NULL,
+			   BCH_READ_last_fragment,
+			   data_opts.scrub ?  data_opts.read_dev : -1);
 	return 0;
-err_free_pages:
-	bio_free_pages(&io->write.op.wbio.bio);
 err_free:
 	kfree(io);
 err:
-	if (ret == -BCH_ERR_data_update_done)
+	if (bch2_err_matches(ret, BCH_ERR_data_update_done))
 		return 0;
 
 	if (bch2_err_matches(ret, EROFS) ||
 	    bch2_err_matches(ret, BCH_ERR_transaction_restart))
 		return ret;
 
-	count_event(c, move_extent_start_fail);
+	count_event(c, io_move_start_fail);
 
-	if (trace_move_extent_start_fail_enabled()) {
+	if (trace_io_move_start_fail_enabled()) {
 		struct printbuf buf = PRINTBUF;
 
 		bch2_bkey_val_to_text(&buf, c, k);
 		prt_str(&buf, ": ");
 		prt_str(&buf, bch2_err_str(ret));
-		trace_move_extent_start_fail(c, buf.buf);
+		trace_io_move_start_fail(c, buf.buf);
 		printbuf_exit(&buf);
 	}
 	return ret;
@@ -518,6 +542,37 @@ int bch2_move_ratelimit(struct moving_context *ctxt)
 	return 0;
 }
 
+/*
+ * Move requires non extents iterators, and there's also no need for it to
+ * signal indirect_extent_missing_error:
+ */
+static struct bkey_s_c bch2_lookup_indirect_extent_for_move(struct btree_trans *trans,
+					    struct btree_iter *iter,
+					    struct bkey_s_c_reflink_p p)
+{
+	if (unlikely(REFLINK_P_ERROR(p.v)))
+		return bkey_s_c_null;
+
+	struct bpos reflink_pos = POS(0, REFLINK_P_IDX(p.v));
+
+	bch2_trans_iter_init(trans, iter,
+			     BTREE_ID_reflink, reflink_pos,
+			     BTREE_ITER_not_extents);
+
+	struct bkey_s_c k = bch2_btree_iter_peek(iter);
+	if (!k.k || bkey_err(k)) {
+		bch2_trans_iter_exit(trans, iter);
+		return k;
+	}
+
+	if (bkey_lt(reflink_pos, bkey_start_pos(k.k))) {
+		bch2_trans_iter_exit(trans, iter);
+		return bkey_s_c_null;
+	}
+
+	return k;
+}
+
 static int bch2_move_data_btree(struct moving_context *ctxt,
 				struct bpos start,
 				struct bpos end,
@@ -551,6 +606,7 @@ static int bch2_move_data_btree(struct moving_context *ctxt,
 	bch2_trans_begin(trans);
 	bch2_trans_iter_init(trans, &iter, btree_id, start,
 			     BTREE_ITER_prefetch|
+			     BTREE_ITER_not_extents|
 			     BTREE_ITER_all_snapshots);
 
 	if (ctxt->rate)
@@ -581,17 +637,16 @@ static int bch2_move_data_btree(struct moving_context *ctxt,
 		    k.k->type == KEY_TYPE_reflink_p &&
 		    REFLINK_P_MAY_UPDATE_OPTIONS(bkey_s_c_to_reflink_p(k).v)) {
 			struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
-			s64 offset_into_extent	= iter.pos.offset - bkey_start_offset(k.k);
 
 			bch2_trans_iter_exit(trans, &reflink_iter);
-			k = bch2_lookup_indirect_extent(trans, &reflink_iter, &offset_into_extent, p, true, 0);
+			k = bch2_lookup_indirect_extent_for_move(trans, &reflink_iter, p);
 			ret = bkey_err(k);
 			if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 				continue;
 			if (ret)
 				break;
 
-			if (bkey_deleted(k.k))
+			if (!k.k)
 				goto next_nondata;
 
 			/*
@@ -627,7 +682,7 @@ static int bch2_move_data_btree(struct moving_context *ctxt,
 			if (bch2_err_matches(ret2, BCH_ERR_transaction_restart))
 				continue;
 
-			if (ret2 == -ENOMEM) {
+			if (bch2_err_matches(ret2, ENOMEM)) {
 				/* memory allocation failure, wait for some IO to finish */
 				bch2_move_ctxt_wait_for_io(ctxt);
 				continue;
@@ -689,21 +744,22 @@ int bch2_move_data(struct bch_fs *c,
 		   bool wait_on_copygc,
 		   move_pred_fn pred, void *arg)
 {
-
 	struct moving_context ctxt;
-	int ret;
 
 	bch2_moving_ctxt_init(&ctxt, c, rate, stats, wp, wait_on_copygc);
-	ret = __bch2_move_data(&ctxt, start, end, pred, arg);
+	int ret = __bch2_move_data(&ctxt, start, end, pred, arg);
 	bch2_moving_ctxt_exit(&ctxt);
 
 	return ret;
 }
 
-int bch2_evacuate_bucket(struct moving_context *ctxt,
-			   struct move_bucket_in_flight *bucket_in_flight,
-			   struct bpos bucket, int gen,
-			   struct data_update_opts _data_opts)
+static int __bch2_move_data_phys(struct moving_context *ctxt,
+			struct move_bucket_in_flight *bucket_in_flight,
+			unsigned dev,
+			u64 bucket_start,
+			u64 bucket_end,
+			unsigned data_types,
+			move_pred_fn pred, void *arg)
 {
 	struct btree_trans *trans = ctxt->trans;
 	struct bch_fs *c = trans->c;
@@ -712,16 +768,19 @@ int bch2_evacuate_bucket(struct moving_context *ctxt,
 	struct btree_iter iter = {}, bp_iter = {};
 	struct bkey_buf sk;
 	struct bkey_s_c k;
-	struct data_update_opts data_opts;
-	unsigned sectors_moved = 0;
 	struct bkey_buf last_flushed;
 	int ret = 0;
 
-	struct bch_dev *ca = bch2_dev_tryget(c, bucket.inode);
+	struct bch_dev *ca = bch2_dev_tryget(c, dev);
 	if (!ca)
 		return 0;
 
-	trace_bucket_evacuate(c, &bucket);
+	bucket_end = min(bucket_end, ca->mi.nbuckets);
+
+	struct bpos bp_start	= bucket_pos_to_bp_start(ca, POS(dev, bucket_start));
+	struct bpos bp_end	= bucket_pos_to_bp_end(ca, POS(dev, bucket_end));
+	bch2_dev_put(ca);
+	ca = NULL;
 
 	bch2_bkey_buf_init(&last_flushed);
 	bkey_init(&last_flushed.k->k);
@@ -732,8 +791,7 @@ int bch2_evacuate_bucket(struct moving_context *ctxt,
 	 */
 	bch2_trans_begin(trans);
 
-	bch2_trans_iter_init(trans, &bp_iter, BTREE_ID_backpointers,
-			     bucket_pos_to_bp_start(ca, bucket), 0);
+	bch2_trans_iter_init(trans, &bp_iter, BTREE_ID_backpointers, bp_start, 0);
 
 	bch_err_msg(c, ret, "looking up alloc key");
 	if (ret)
@@ -757,7 +815,7 @@ int bch2_evacuate_bucket(struct moving_context *ctxt,
 		if (ret)
 			goto err;
 
-		if (!k.k || bkey_gt(k.k->p, bucket_pos_to_bp_end(ca, bucket)))
+		if (!k.k || bkey_gt(k.k->p, bp_end))
 			break;
 
 		if (k.k->type != KEY_TYPE_backpointer)
@@ -765,107 +823,148 @@ int bch2_evacuate_bucket(struct moving_context *ctxt,
 
 		struct bkey_s_c_backpointer bp = bkey_s_c_to_backpointer(k);
 
-		if (!bp.v->level) {
-			k = bch2_backpointer_get_key(trans, bp, &iter, 0, &last_flushed);
-			ret = bkey_err(k);
-			if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
-				continue;
-			if (ret)
-				goto err;
-			if (!k.k)
-				goto next;
+		if (ctxt->stats)
+			ctxt->stats->offset = bp.k->p.offset >> MAX_EXTENT_COMPRESS_RATIO_SHIFT;
+
+		if (!(data_types & BIT(bp.v->data_type)))
+			goto next;
+
+		if (!bp.v->level && bp.v->btree_id == BTREE_ID_stripes)
+			goto next;
 
-			bch2_bkey_buf_reassemble(&sk, c, k);
-			k = bkey_i_to_s_c(sk.k);
+		k = bch2_backpointer_get_key(trans, bp, &iter, 0, &last_flushed);
+		ret = bkey_err(k);
+		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
+			continue;
+		if (ret)
+			goto err;
+		if (!k.k)
+			goto next;
 
+		if (!bp.v->level) {
 			ret = bch2_move_get_io_opts_one(trans, &io_opts, &iter, k);
 			if (ret) {
 				bch2_trans_iter_exit(trans, &iter);
 				continue;
 			}
+		}
 
-			data_opts = _data_opts;
-			data_opts.target	= io_opts.background_target;
-			data_opts.rewrite_ptrs = 0;
-
-			unsigned sectors = bp.v->bucket_len; /* move_extent will drop locks */
-			unsigned i = 0;
-			const union bch_extent_entry *entry;
-			struct extent_ptr_decoded p;
-			bkey_for_each_ptr_decode(k.k, bch2_bkey_ptrs_c(k), p, entry) {
-				if (p.ptr.dev == bucket.inode) {
-					if (p.ptr.cached) {
-						bch2_trans_iter_exit(trans, &iter);
-						goto next;
-					}
-					data_opts.rewrite_ptrs |= 1U << i;
-					break;
-				}
-				i++;
-			}
-
-			ret = bch2_move_extent(ctxt, bucket_in_flight,
-					       &iter, k, io_opts, data_opts);
+		struct data_update_opts data_opts = {};
+		if (!pred(c, arg, k, &io_opts, &data_opts)) {
 			bch2_trans_iter_exit(trans, &iter);
+			goto next;
+		}
 
-			if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
-				continue;
-			if (ret == -ENOMEM) {
-				/* memory allocation failure, wait for some IO to finish */
-				bch2_move_ctxt_wait_for_io(ctxt);
-				continue;
-			}
-			if (ret)
-				goto err;
-
-			if (ctxt->stats)
-				atomic64_add(sectors, &ctxt->stats->sectors_seen);
-			sectors_moved += sectors;
-		} else {
-			struct btree *b;
+		if (data_opts.scrub &&
+		    !bch2_dev_idx_is_online(c, data_opts.read_dev)) {
+			bch2_trans_iter_exit(trans, &iter);
+			ret = -BCH_ERR_device_offline;
+			break;
+		}
 
-			b = bch2_backpointer_get_node(trans, bp, &iter, &last_flushed);
-			ret = PTR_ERR_OR_ZERO(b);
-			if (ret == -BCH_ERR_backpointer_to_overwritten_btree_node)
-				goto next;
-			if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
-				continue;
-			if (ret)
-				goto err;
-			if (!b)
-				goto next;
+		bch2_bkey_buf_reassemble(&sk, c, k);
+		k = bkey_i_to_s_c(sk.k);
 
-			unsigned sectors = btree_ptr_sectors_written(bkey_i_to_s_c(&b->key));
+		/* move_extent will drop locks */
+		unsigned sectors = bp.v->bucket_len;
 
-			ret = bch2_btree_node_rewrite(trans, &iter, b, 0);
-			bch2_trans_iter_exit(trans, &iter);
+		if (!bp.v->level)
+			ret = bch2_move_extent(ctxt, bucket_in_flight, &iter, k, io_opts, data_opts);
+		else if (!data_opts.scrub)
+			ret = bch2_btree_node_rewrite_pos(trans, bp.v->btree_id, bp.v->level, k.k->p, 0);
+		else
+			ret = bch2_btree_node_scrub(trans, bp.v->btree_id, bp.v->level, k, data_opts.read_dev);
 
-			if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
-				continue;
-			if (ret)
-				goto err;
+		bch2_trans_iter_exit(trans, &iter);
 
-			if (ctxt->rate)
-				bch2_ratelimit_increment(ctxt->rate, sectors);
-			if (ctxt->stats) {
-				atomic64_add(sectors, &ctxt->stats->sectors_seen);
-				atomic64_add(sectors, &ctxt->stats->sectors_moved);
-			}
-			sectors_moved += btree_sectors(c);
+		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
+			continue;
+		if (ret == -ENOMEM) {
+			/* memory allocation failure, wait for some IO to finish */
+			bch2_move_ctxt_wait_for_io(ctxt);
+			continue;
 		}
+		if (ret)
+			goto err;
+
+		if (ctxt->stats)
+			atomic64_add(sectors, &ctxt->stats->sectors_seen);
 next:
 		bch2_btree_iter_advance(&bp_iter);
 	}
-
-	trace_evacuate_bucket(c, &bucket, sectors_moved, ca->mi.bucket_size, ret);
 err:
 	bch2_trans_iter_exit(trans, &bp_iter);
-	bch2_dev_put(ca);
 	bch2_bkey_buf_exit(&sk, c);
 	bch2_bkey_buf_exit(&last_flushed, c);
 	return ret;
 }
 
+static int bch2_move_data_phys(struct bch_fs *c,
+			       unsigned dev,
+			       u64 start,
+			       u64 end,
+			       unsigned data_types,
+			       struct bch_ratelimit *rate,
+			       struct bch_move_stats *stats,
+			       struct write_point_specifier wp,
+			       bool wait_on_copygc,
+			       move_pred_fn pred, void *arg)
+{
+	struct moving_context ctxt;
+
+	bch2_trans_run(c, bch2_btree_write_buffer_flush_sync(trans));
+
+	bch2_moving_ctxt_init(&ctxt, c, rate, stats, wp, wait_on_copygc);
+	ctxt.stats->phys = true;
+	ctxt.stats->data_type = (int) DATA_PROGRESS_DATA_TYPE_phys;
+
+	int ret = __bch2_move_data_phys(&ctxt, NULL, dev, start, end, data_types, pred, arg);
+	bch2_moving_ctxt_exit(&ctxt);
+
+	return ret;
+}
+
+struct evacuate_bucket_arg {
+	struct bpos		bucket;
+	int			gen;
+	struct data_update_opts	data_opts;
+};
+
+static bool evacuate_bucket_pred(struct bch_fs *c, void *_arg, struct bkey_s_c k,
+				 struct bch_io_opts *io_opts,
+				 struct data_update_opts *data_opts)
+{
+	struct evacuate_bucket_arg *arg = _arg;
+
+	*data_opts = arg->data_opts;
+
+	unsigned i = 0;
+	bkey_for_each_ptr(bch2_bkey_ptrs_c(k), ptr) {
+		if (ptr->dev == arg->bucket.inode &&
+		    (arg->gen < 0 || arg->gen == ptr->gen) &&
+		    !ptr->cached)
+			data_opts->rewrite_ptrs |= BIT(i);
+		i++;
+	}
+
+	return data_opts->rewrite_ptrs != 0;
+}
+
+int bch2_evacuate_bucket(struct moving_context *ctxt,
+			   struct move_bucket_in_flight *bucket_in_flight,
+			   struct bpos bucket, int gen,
+			   struct data_update_opts data_opts)
+{
+	struct evacuate_bucket_arg arg = { bucket, gen, data_opts, };
+
+	return __bch2_move_data_phys(ctxt, bucket_in_flight,
+				   bucket.inode,
+				   bucket.offset,
+				   bucket.offset + 1,
+				   ~0,
+				   evacuate_bucket_pred, &arg);
+}
+
 typedef bool (*move_btree_pred)(struct bch_fs *, void *,
 				struct btree *, struct bch_io_opts *,
 				struct data_update_opts *);
@@ -1007,14 +1106,6 @@ static bool rereplicate_btree_pred(struct bch_fs *c, void *arg,
 	return rereplicate_pred(c, arg, bkey_i_to_s_c(&b->key), io_opts, data_opts);
 }
 
-static bool migrate_btree_pred(struct bch_fs *c, void *arg,
-			       struct btree *b,
-			       struct bch_io_opts *io_opts,
-			       struct data_update_opts *data_opts)
-{
-	return migrate_pred(c, arg, bkey_i_to_s_c(&b->key), io_opts, data_opts);
-}
-
 /*
  * Ancient versions of bcachefs produced packed formats which could represent
  * keys that the in memory format cannot represent; this checks for those
@@ -1104,6 +1195,30 @@ static bool drop_extra_replicas_btree_pred(struct bch_fs *c, void *arg,
 	return drop_extra_replicas_pred(c, arg, bkey_i_to_s_c(&b->key), io_opts, data_opts);
 }
 
+static bool scrub_pred(struct bch_fs *c, void *_arg,
+		       struct bkey_s_c k,
+		       struct bch_io_opts *io_opts,
+		       struct data_update_opts *data_opts)
+{
+	struct bch_ioctl_data *arg = _arg;
+
+	if (k.k->type != KEY_TYPE_btree_ptr_v2) {
+		struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+		const union bch_extent_entry *entry;
+		struct extent_ptr_decoded p;
+		bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
+			if (p.ptr.dev == arg->migrate.dev) {
+				if (!p.crc.csum_type)
+					return false;
+				break;
+			}
+	}
+
+	data_opts->scrub	= true;
+	data_opts->read_dev	= arg->migrate.dev;
+	return true;
+}
+
 int bch2_data_job(struct bch_fs *c,
 		  struct bch_move_stats *stats,
 		  struct bch_ioctl_data op)
@@ -1118,6 +1233,22 @@ int bch2_data_job(struct bch_fs *c,
 	bch2_move_stats_init(stats, bch2_data_ops_strs[op.op]);
 
 	switch (op.op) {
+	case BCH_DATA_OP_scrub:
+		/*
+		 * prevent tests from spuriously failing, make sure we see all
+		 * btree nodes that need to be repaired
+		 */
+		bch2_btree_interior_updates_flush(c);
+
+		ret = bch2_move_data_phys(c, op.scrub.dev, 0, U64_MAX,
+					  op.scrub.data_types,
+					  NULL,
+					  stats,
+					  writepoint_hashed((unsigned long) current),
+					  false,
+					  scrub_pred, &op) ?: ret;
+		break;
+
 	case BCH_DATA_OP_rereplicate:
 		stats->data_type = BCH_DATA_journal;
 		ret = bch2_journal_flush_device_pins(&c->journal, -1);
@@ -1137,14 +1268,14 @@ int bch2_data_job(struct bch_fs *c,
 
 		stats->data_type = BCH_DATA_journal;
 		ret = bch2_journal_flush_device_pins(&c->journal, op.migrate.dev);
-		ret = bch2_move_btree(c, start, end,
-				      migrate_btree_pred, &op, stats) ?: ret;
-		ret = bch2_move_data(c, start, end,
-				     NULL,
-				     stats,
-				     writepoint_hashed((unsigned long) current),
-				     true,
-				     migrate_pred, &op) ?: ret;
+		ret = bch2_move_data_phys(c, op.migrate.dev, 0, U64_MAX,
+					  ~0,
+					  NULL,
+					  stats,
+					  writepoint_hashed((unsigned long) current),
+					  true,
+					  migrate_pred, &op) ?: ret;
+		bch2_btree_interior_updates_flush(c);
 		ret = bch2_replicas_gc2(c) ?: ret;
 		break;
 	case BCH_DATA_OP_rewrite_old_nodes:
@@ -1176,17 +1307,17 @@ void bch2_move_stats_to_text(struct printbuf *out, struct bch_move_stats *stats)
 	prt_newline(out);
 	printbuf_indent_add(out, 2);
 
-	prt_printf(out, "keys moved:  %llu\n",	atomic64_read(&stats->keys_moved));
-	prt_printf(out, "keys raced:  %llu\n",	atomic64_read(&stats->keys_raced));
-	prt_printf(out, "bytes seen:  ");
+	prt_printf(out, "keys moved:\t%llu\n",	atomic64_read(&stats->keys_moved));
+	prt_printf(out, "keys raced:\t%llu\n",	atomic64_read(&stats->keys_raced));
+	prt_printf(out, "bytes seen:\t");
 	prt_human_readable_u64(out, atomic64_read(&stats->sectors_seen) << 9);
 	prt_newline(out);
 
-	prt_printf(out, "bytes moved: ");
+	prt_printf(out, "bytes moved:\t");
 	prt_human_readable_u64(out, atomic64_read(&stats->sectors_moved) << 9);
 	prt_newline(out);
 
-	prt_printf(out, "bytes raced: ");
+	prt_printf(out, "bytes raced:\t");
 	prt_human_readable_u64(out, atomic64_read(&stats->sectors_raced) << 9);
 	prt_newline(out);
 
@@ -1195,7 +1326,8 @@ void bch2_move_stats_to_text(struct printbuf *out, struct bch_move_stats *stats)
 
 static void bch2_moving_ctxt_to_text(struct printbuf *out, struct bch_fs *c, struct moving_context *ctxt)
 {
-	struct moving_io *io;
+	if (!out->nr_tabstops)
+		printbuf_tabstop_push(out, 32);
 
 	bch2_move_stats_to_text(out, ctxt->stats);
 	printbuf_indent_add(out, 2);
@@ -1215,8 +1347,9 @@ static void bch2_moving_ctxt_to_text(struct printbuf *out, struct bch_fs *c, str
 	printbuf_indent_add(out, 2);
 
 	mutex_lock(&ctxt->lock);
+	struct moving_io *io;
 	list_for_each_entry(io, &ctxt->ios, io_list)
-		bch2_write_op_to_text(out, &io->write.op);
+		bch2_data_update_inflight_to_text(out, &io->write);
 	mutex_unlock(&ctxt->lock);
 
 	printbuf_indent_sub(out, 4);
diff --git a/fs/bcachefs/move_types.h b/fs/bcachefs/move_types.h
index e22841ef31e4..807f779f6f76 100644
--- a/fs/bcachefs/move_types.h
+++ b/fs/bcachefs/move_types.h
@@ -3,22 +3,36 @@
 #define _BCACHEFS_MOVE_TYPES_H
 
 #include "bbpos_types.h"
+#include "bcachefs_ioctl.h"
 
 struct bch_move_stats {
-	enum bch_data_type	data_type;
-	struct bbpos		pos;
 	char			name[32];
+	bool			phys;
+	enum bch_ioctl_data_event_ret	ret;
+
+	union {
+	struct {
+		enum bch_data_type	data_type;
+		struct bbpos		pos;
+	};
+	struct {
+		unsigned		dev;
+		u64			offset;
+	};
+	};
 
 	atomic64_t		keys_moved;
 	atomic64_t		keys_raced;
 	atomic64_t		sectors_seen;
 	atomic64_t		sectors_moved;
 	atomic64_t		sectors_raced;
+	atomic64_t		sectors_error_corrected;
+	atomic64_t		sectors_error_uncorrected;
 };
 
 struct move_bucket_key {
 	struct bpos		bucket;
-	u8			gen;
+	unsigned		gen;
 };
 
 struct move_bucket {
diff --git a/fs/bcachefs/movinggc.c b/fs/bcachefs/movinggc.c
index 6718dc37c5a3..5126c870ce5b 100644
--- a/fs/bcachefs/movinggc.c
+++ b/fs/bcachefs/movinggc.c
@@ -167,8 +167,8 @@ static int bch2_copygc_get_buckets(struct moving_context *ctxt,
 	bch2_trans_begin(trans);
 
 	ret = for_each_btree_key_max(trans, iter, BTREE_ID_lru,
-				  lru_pos(BCH_LRU_FRAGMENTATION_START, 0, 0),
-				  lru_pos(BCH_LRU_FRAGMENTATION_START, U64_MAX, LRU_TIME_MAX),
+				  lru_pos(BCH_LRU_BUCKET_FRAGMENTATION, 0, 0),
+				  lru_pos(BCH_LRU_BUCKET_FRAGMENTATION, U64_MAX, LRU_TIME_MAX),
 				  0, k, ({
 		struct move_bucket b = { .k.bucket = u64_to_bucket(k.k->p.offset) };
 		int ret2 = 0;
@@ -317,6 +317,17 @@ void bch2_copygc_wait_to_text(struct printbuf *out, struct bch_fs *c)
 	prt_printf(out, "Currently calculated wait:\t");
 	prt_human_readable_u64(out, bch2_copygc_wait_amount(c));
 	prt_newline(out);
+
+	rcu_read_lock();
+	struct task_struct *t = rcu_dereference(c->copygc_thread);
+	if (t)
+		get_task_struct(t);
+	rcu_read_unlock();
+
+	if (t) {
+		bch2_prt_task_backtrace(out, t, 0, GFP_KERNEL);
+		put_task_struct(t);
+	}
 }
 
 static int bch2_copygc_thread(void *arg)
diff --git a/fs/bcachefs/fs-common.c b/fs/bcachefs/namei.c
similarity index 73%
rename from fs/bcachefs/fs-common.c
rename to fs/bcachefs/namei.c
index 2c3d46ac70c6..93246ad31541 100644
--- a/fs/bcachefs/fs-common.c
+++ b/fs/bcachefs/namei.c
@@ -4,8 +4,8 @@
 #include "acl.h"
 #include "btree_update.h"
 #include "dirent.h"
-#include "fs-common.h"
 #include "inode.h"
+#include "namei.h"
 #include "subvolume.h"
 #include "xattr.h"
 
@@ -47,6 +47,10 @@ int bch2_create_trans(struct btree_trans *trans,
 	if (ret)
 		goto err;
 
+	/* Inherit casefold state from parent. */
+	if (S_ISDIR(mode))
+		new_inode->bi_flags |= dir_u->bi_flags & BCH_INODE_casefolded;
+
 	if (!(flags & BCH_CREATE_SNAPSHOT)) {
 		/* Normal create path - allocate a new inode: */
 		bch2_inode_init_late(new_inode, now, uid, gid, mode, rdev, dir_u);
@@ -153,16 +157,14 @@ int bch2_create_trans(struct btree_trans *trans,
 			dir_u->bi_nlink++;
 		dir_u->bi_mtime = dir_u->bi_ctime = now;
 
-		ret = bch2_inode_write(trans, &dir_iter, dir_u);
-		if (ret)
-			goto err;
-
-		ret = bch2_dirent_create(trans, dir, &dir_hash,
-					 dir_type,
-					 name,
-					 dir_target,
-					 &dir_offset,
-					 STR_HASH_must_create|BTREE_ITER_with_updates);
+		ret =   bch2_dirent_create(trans, dir, &dir_hash,
+					   dir_type,
+					   name,
+					   dir_target,
+					   &dir_offset,
+					   &dir_u->bi_size,
+					   STR_HASH_must_create|BTREE_ITER_with_updates) ?:
+			bch2_inode_write(trans, &dir_iter, dir_u);
 		if (ret)
 			goto err;
 
@@ -225,7 +227,9 @@ int bch2_link_trans(struct btree_trans *trans,
 
 	ret = bch2_dirent_create(trans, dir, &dir_hash,
 				 mode_to_type(inode_u->bi_mode),
-				 name, inum.inum, &dir_offset,
+				 name, inum.inum,
+				 &dir_offset,
+				 &dir_u->bi_size,
 				 STR_HASH_must_create);
 	if (ret)
 		goto err;
@@ -417,8 +421,8 @@ int bch2_rename_trans(struct btree_trans *trans,
 	}
 
 	ret = bch2_dirent_rename(trans,
-				 src_dir, &src_hash,
-				 dst_dir, &dst_hash,
+				 src_dir, &src_hash, &src_dir_u->bi_size,
+				 dst_dir, &dst_hash, &dst_dir_u->bi_size,
 				 src_name, &src_inum, &src_offset,
 				 dst_name, &dst_inum, &dst_offset,
 				 mode);
@@ -560,6 +564,8 @@ int bch2_rename_trans(struct btree_trans *trans,
 	return ret;
 }
 
+/* inum_to_path */
+
 static inline void prt_bytes_reversed(struct printbuf *out, const void *b, unsigned n)
 {
 	bch2_printbuf_make_room(out, n);
@@ -650,3 +656,179 @@ int bch2_inum_to_path(struct btree_trans *trans, subvol_inum inum, struct printb
 	prt_str_reversed(path, "(disconnected)");
 	goto out;
 }
+
+/* fsck */
+
+static int bch2_check_dirent_inode_dirent(struct btree_trans *trans,
+					  struct bkey_s_c_dirent d,
+					  struct bch_inode_unpacked *target,
+					  bool in_fsck)
+{
+	struct bch_fs *c = trans->c;
+	struct printbuf buf = PRINTBUF;
+	struct btree_iter bp_iter = { NULL };
+	int ret = 0;
+
+	if (inode_points_to_dirent(target, d))
+		return 0;
+
+	if (!target->bi_dir &&
+	    !target->bi_dir_offset) {
+		fsck_err_on(S_ISDIR(target->bi_mode),
+			    trans, inode_dir_missing_backpointer,
+			    "directory with missing backpointer\n%s",
+			    (printbuf_reset(&buf),
+			     bch2_bkey_val_to_text(&buf, c, d.s_c),
+			     prt_printf(&buf, "\n"),
+			     bch2_inode_unpacked_to_text(&buf, target),
+			     buf.buf));
+
+		fsck_err_on(target->bi_flags & BCH_INODE_unlinked,
+			    trans, inode_unlinked_but_has_dirent,
+			    "inode unlinked but has dirent\n%s",
+			    (printbuf_reset(&buf),
+			     bch2_bkey_val_to_text(&buf, c, d.s_c),
+			     prt_printf(&buf, "\n"),
+			     bch2_inode_unpacked_to_text(&buf, target),
+			     buf.buf));
+
+		target->bi_flags &= ~BCH_INODE_unlinked;
+		target->bi_dir		= d.k->p.inode;
+		target->bi_dir_offset	= d.k->p.offset;
+		return __bch2_fsck_write_inode(trans, target);
+	}
+
+	if (bch2_inode_should_have_single_bp(target) &&
+	    !fsck_err(trans, inode_wrong_backpointer,
+		      "dirent points to inode that does not point back:\n  %s",
+		      (bch2_bkey_val_to_text(&buf, c, d.s_c),
+		       prt_printf(&buf, "\n  "),
+		       bch2_inode_unpacked_to_text(&buf, target),
+		       buf.buf)))
+		goto err;
+
+	struct bkey_s_c_dirent bp_dirent =
+		bch2_bkey_get_iter_typed(trans, &bp_iter, BTREE_ID_dirents,
+			      SPOS(target->bi_dir, target->bi_dir_offset, target->bi_snapshot),
+			      0, dirent);
+	ret = bkey_err(bp_dirent);
+	if (ret && !bch2_err_matches(ret, ENOENT))
+		goto err;
+
+	bool backpointer_exists = !ret;
+	ret = 0;
+
+	if (!backpointer_exists) {
+		if (fsck_err(trans, inode_wrong_backpointer,
+			     "inode %llu:%u has wrong backpointer:\n"
+			     "got       %llu:%llu\n"
+			     "should be %llu:%llu",
+			     target->bi_inum, target->bi_snapshot,
+			     target->bi_dir,
+			     target->bi_dir_offset,
+			     d.k->p.inode,
+			     d.k->p.offset)) {
+			target->bi_dir		= d.k->p.inode;
+			target->bi_dir_offset	= d.k->p.offset;
+			ret = __bch2_fsck_write_inode(trans, target);
+		}
+	} else {
+		bch2_bkey_val_to_text(&buf, c, d.s_c);
+		prt_newline(&buf);
+		bch2_bkey_val_to_text(&buf, c, bp_dirent.s_c);
+
+		if (S_ISDIR(target->bi_mode) || target->bi_subvol) {
+			/*
+			 * XXX: verify connectivity of the other dirent
+			 * up to the root before removing this one
+			 *
+			 * Additionally, bch2_lookup would need to cope with the
+			 * dirent it found being removed - or should we remove
+			 * the other one, even though the inode points to it?
+			 */
+			if (in_fsck) {
+				if (fsck_err(trans, inode_dir_multiple_links,
+					     "%s %llu:%u with multiple links\n%s",
+					     S_ISDIR(target->bi_mode) ? "directory" : "subvolume",
+					     target->bi_inum, target->bi_snapshot, buf.buf))
+					ret = bch2_fsck_remove_dirent(trans, d.k->p);
+			} else {
+				bch2_fs_inconsistent(c,
+						"%s %llu:%u with multiple links\n%s",
+						S_ISDIR(target->bi_mode) ? "directory" : "subvolume",
+						target->bi_inum, target->bi_snapshot, buf.buf);
+			}
+
+			goto out;
+		} else {
+			/*
+			 * hardlinked file with nlink 0:
+			 * We're just adjusting nlink here so check_nlinks() will pick
+			 * it up, it ignores inodes with nlink 0
+			 */
+			if (fsck_err_on(!target->bi_nlink,
+					trans, inode_multiple_links_but_nlink_0,
+					"inode %llu:%u type %s has multiple links but i_nlink 0\n%s",
+					target->bi_inum, target->bi_snapshot, bch2_d_types[d.v->d_type], buf.buf)) {
+				target->bi_nlink++;
+				target->bi_flags &= ~BCH_INODE_unlinked;
+				ret = __bch2_fsck_write_inode(trans, target);
+				if (ret)
+					goto err;
+			}
+		}
+	}
+out:
+err:
+fsck_err:
+	bch2_trans_iter_exit(trans, &bp_iter);
+	printbuf_exit(&buf);
+	bch_err_fn(c, ret);
+	return ret;
+}
+
+int __bch2_check_dirent_target(struct btree_trans *trans,
+			       struct btree_iter *dirent_iter,
+			       struct bkey_s_c_dirent d,
+			       struct bch_inode_unpacked *target,
+			       bool in_fsck)
+{
+	struct bch_fs *c = trans->c;
+	struct printbuf buf = PRINTBUF;
+	int ret = 0;
+
+	ret = bch2_check_dirent_inode_dirent(trans, d, target, in_fsck);
+	if (ret)
+		goto err;
+
+	if (fsck_err_on(d.v->d_type != inode_d_type(target),
+			trans, dirent_d_type_wrong,
+			"incorrect d_type: got %s, should be %s:\n%s",
+			bch2_d_type_str(d.v->d_type),
+			bch2_d_type_str(inode_d_type(target)),
+			(printbuf_reset(&buf),
+			 bch2_bkey_val_to_text(&buf, c, d.s_c), buf.buf))) {
+		struct bkey_i_dirent *n = bch2_trans_kmalloc(trans, bkey_bytes(d.k));
+		ret = PTR_ERR_OR_ZERO(n);
+		if (ret)
+			goto err;
+
+		bkey_reassemble(&n->k_i, d.s_c);
+		n->v.d_type = inode_d_type(target);
+		if (n->v.d_type == DT_SUBVOL) {
+			n->v.d_parent_subvol = cpu_to_le32(target->bi_parent_subvol);
+			n->v.d_child_subvol = cpu_to_le32(target->bi_subvol);
+		} else {
+			n->v.d_inum = cpu_to_le64(target->bi_inum);
+		}
+
+		ret = bch2_trans_update(trans, dirent_iter, &n->k_i, 0);
+		if (ret)
+			goto err;
+	}
+err:
+fsck_err:
+	printbuf_exit(&buf);
+	bch_err_fn(c, ret);
+	return ret;
+}
diff --git a/fs/bcachefs/fs-common.h b/fs/bcachefs/namei.h
similarity index 61%
rename from fs/bcachefs/fs-common.h
rename to fs/bcachefs/namei.h
index 2b59210bb5e8..2e6f6364767f 100644
--- a/fs/bcachefs/fs-common.h
+++ b/fs/bcachefs/namei.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _BCACHEFS_FS_COMMON_H
-#define _BCACHEFS_FS_COMMON_H
+#ifndef _BCACHEFS_NAMEI_H
+#define _BCACHEFS_NAMEI_H
 
 #include "dirent.h"
 
@@ -44,4 +44,29 @@ bool bch2_reinherit_attrs(struct bch_inode_unpacked *,
 
 int bch2_inum_to_path(struct btree_trans *, subvol_inum, struct printbuf *);
 
-#endif /* _BCACHEFS_FS_COMMON_H */
+int __bch2_check_dirent_target(struct btree_trans *,
+			       struct btree_iter *,
+			       struct bkey_s_c_dirent,
+			       struct bch_inode_unpacked *, bool);
+
+static inline bool inode_points_to_dirent(struct bch_inode_unpacked *inode,
+					  struct bkey_s_c_dirent d)
+{
+	return  inode->bi_dir		== d.k->p.inode &&
+		inode->bi_dir_offset	== d.k->p.offset;
+}
+
+static inline int bch2_check_dirent_target(struct btree_trans *trans,
+					   struct btree_iter *dirent_iter,
+					   struct bkey_s_c_dirent d,
+					   struct bch_inode_unpacked *target,
+					   bool in_fsck)
+{
+	if (likely(inode_points_to_dirent(target, d) &&
+		   d.v->d_type == inode_d_type(target)))
+		return 0;
+
+	return __bch2_check_dirent_target(trans, dirent_iter, d, target, in_fsck);
+}
+
+#endif /* _BCACHEFS_NAMEI_H */
diff --git a/fs/bcachefs/opts.c b/fs/bcachefs/opts.c
index 6772faf385a5..4eea51edafca 100644
--- a/fs/bcachefs/opts.c
+++ b/fs/bcachefs/opts.c
@@ -44,7 +44,7 @@ const char * const __bch2_btree_ids[] = {
 	NULL
 };
 
-static const char * const __bch2_csum_types[] = {
+const char * const __bch2_csum_types[] = {
 	BCH_CSUM_TYPES()
 	NULL
 };
@@ -163,16 +163,6 @@ const char * const bch2_d_types[BCH_DT_MAX] = {
 	[DT_SUBVOL]	= "subvol",
 };
 
-u64 BCH2_NO_SB_OPT(const struct bch_sb *sb)
-{
-	BUG();
-}
-
-void SET_BCH2_NO_SB_OPT(struct bch_sb *sb, u64 v)
-{
-	BUG();
-}
-
 void bch2_opts_apply(struct bch_opts *dst, struct bch_opts src)
 {
 #define x(_name, ...)						\
@@ -223,6 +213,21 @@ void bch2_opt_set_by_id(struct bch_opts *opts, enum bch_opt_id id, u64 v)
 	}
 }
 
+/* dummy option, for options that aren't stored in the superblock */
+typedef u64 (*sb_opt_get_fn)(const struct bch_sb *);
+typedef void (*sb_opt_set_fn)(struct bch_sb *, u64);
+typedef u64 (*member_opt_get_fn)(const struct bch_member *);
+typedef void (*member_opt_set_fn)(struct bch_member *, u64);
+
+__maybe_unused static const sb_opt_get_fn	BCH2_NO_SB_OPT = NULL;
+__maybe_unused static const sb_opt_set_fn	SET_BCH2_NO_SB_OPT = NULL;
+__maybe_unused static const member_opt_get_fn	BCH2_NO_MEMBER_OPT = NULL;
+__maybe_unused static const member_opt_set_fn	SET_BCH2_NO_MEMBER_OPT = NULL;
+
+#define type_compatible_or_null(_p, _type)				\
+	__builtin_choose_expr(						\
+		__builtin_types_compatible_p(typeof(_p), typeof(_type)), _p, NULL)
+
 const struct bch_option bch2_opt_table[] = {
 #define OPT_BOOL()		.type = BCH_OPT_BOOL, .min = 0, .max = 2
 #define OPT_UINT(_min, _max)	.type = BCH_OPT_UINT,			\
@@ -239,15 +244,15 @@ const struct bch_option bch2_opt_table[] = {
 
 #define x(_name, _bits, _flags, _type, _sb_opt, _default, _hint, _help)	\
 	[Opt_##_name] = {						\
-		.attr	= {						\
-			.name	= #_name,				\
-			.mode = (_flags) & OPT_RUNTIME ? 0644 : 0444,	\
-		},							\
-		.flags	= _flags,					\
-		.hint	= _hint,					\
-		.help	= _help,					\
-		.get_sb = _sb_opt,					\
-		.set_sb	= SET_##_sb_opt,				\
+		.attr.name	= #_name,				\
+		.attr.mode	= (_flags) & OPT_RUNTIME ? 0644 : 0444,	\
+		.flags		= _flags,				\
+		.hint		= _hint,				\
+		.help		= _help,				\
+		.get_sb		= type_compatible_or_null(_sb_opt,	*BCH2_NO_SB_OPT),	\
+		.set_sb		= type_compatible_or_null(SET_##_sb_opt,*SET_BCH2_NO_SB_OPT),	\
+		.get_member	= type_compatible_or_null(_sb_opt,	*BCH2_NO_MEMBER_OPT),	\
+		.set_member	= type_compatible_or_null(SET_##_sb_opt,*SET_BCH2_NO_MEMBER_OPT),\
 		_type							\
 	},
 
@@ -475,11 +480,18 @@ void bch2_opts_to_text(struct printbuf *out,
 	}
 }
 
-int bch2_opt_check_may_set(struct bch_fs *c, int id, u64 v)
+int bch2_opt_check_may_set(struct bch_fs *c, struct bch_dev *ca, int id, u64 v)
 {
+	lockdep_assert_held(&c->state_lock);
+
 	int ret = 0;
 
 	switch (id) {
+	case Opt_state:
+		if (ca)
+			return __bch2_dev_set_state(c, ca, v, BCH_FORCE_IF_DEGRADED);
+		break;
+
 	case Opt_compression:
 	case Opt_background_compression:
 		ret = bch2_check_set_has_compressed_data(c, v);
@@ -495,12 +507,8 @@ int bch2_opt_check_may_set(struct bch_fs *c, int id, u64 v)
 
 int bch2_opts_check_may_set(struct bch_fs *c)
 {
-	unsigned i;
-	int ret;
-
-	for (i = 0; i < bch2_opts_nr; i++) {
-		ret = bch2_opt_check_may_set(c, i,
-				bch2_opt_get_by_id(&c->opts, i));
+	for (unsigned i = 0; i < bch2_opts_nr; i++) {
+		int ret = bch2_opt_check_may_set(c, NULL, i, bch2_opt_get_by_id(&c->opts, i));
 		if (ret)
 			return ret;
 	}
@@ -619,12 +627,25 @@ int bch2_parse_mount_opts(struct bch_fs *c, struct bch_opts *opts,
 	return ret;
 }
 
-u64 bch2_opt_from_sb(struct bch_sb *sb, enum bch_opt_id id)
+u64 bch2_opt_from_sb(struct bch_sb *sb, enum bch_opt_id id, int dev_idx)
 {
 	const struct bch_option *opt = bch2_opt_table + id;
 	u64 v;
 
-	v = opt->get_sb(sb);
+	if (dev_idx < 0) {
+		v = opt->get_sb(sb);
+	} else {
+		if (WARN(!bch2_member_exists(sb, dev_idx),
+			 "tried to set device option %s on nonexistent device %i",
+			 opt->attr.name, dev_idx))
+			return 0;
+
+		struct bch_member m = bch2_sb_member_get(sb, dev_idx);
+		v = opt->get_member(&m);
+	}
+
+	if (opt->flags & OPT_SB_FIELD_ONE_BIAS)
+		--v;
 
 	if (opt->flags & OPT_SB_FIELD_ILOG2)
 		v = 1ULL << v;
@@ -641,35 +662,19 @@ u64 bch2_opt_from_sb(struct bch_sb *sb, enum bch_opt_id id)
  */
 int bch2_opts_from_sb(struct bch_opts *opts, struct bch_sb *sb)
 {
-	unsigned id;
-
-	for (id = 0; id < bch2_opts_nr; id++) {
+	for (unsigned id = 0; id < bch2_opts_nr; id++) {
 		const struct bch_option *opt = bch2_opt_table + id;
 
-		if (opt->get_sb == BCH2_NO_SB_OPT)
-			continue;
-
-		bch2_opt_set_by_id(opts, id, bch2_opt_from_sb(sb, id));
+		if (opt->get_sb)
+			bch2_opt_set_by_id(opts, id, bch2_opt_from_sb(sb, id, -1));
 	}
 
 	return 0;
 }
 
-struct bch_dev_sb_opt_set {
-	void			(*set_sb)(struct bch_member *, u64);
-};
-
-static const struct bch_dev_sb_opt_set bch2_dev_sb_opt_setters [] = {
-#define x(n, set)	[Opt_##n] = { .set_sb = SET_##set },
-	BCH_DEV_OPT_SETTERS()
-#undef x
-};
-
 void __bch2_opt_set_sb(struct bch_sb *sb, int dev_idx,
 		       const struct bch_option *opt, u64 v)
 {
-	enum bch_opt_id id = opt - bch2_opt_table;
-
 	if (opt->flags & OPT_SB_FIELD_SECTORS)
 		v >>= 9;
 
@@ -679,24 +684,16 @@ void __bch2_opt_set_sb(struct bch_sb *sb, int dev_idx,
 	if (opt->flags & OPT_SB_FIELD_ONE_BIAS)
 		v++;
 
-	if (opt->flags & OPT_FS) {
-		if (opt->set_sb != SET_BCH2_NO_SB_OPT)
-			opt->set_sb(sb, v);
-	}
+	if ((opt->flags & OPT_FS) && opt->set_sb && dev_idx < 0)
+		opt->set_sb(sb, v);
 
-	if ((opt->flags & OPT_DEVICE) && dev_idx >= 0) {
+	if ((opt->flags & OPT_DEVICE) && opt->set_member && dev_idx >= 0) {
 		if (WARN(!bch2_member_exists(sb, dev_idx),
 			 "tried to set device option %s on nonexistent device %i",
 			 opt->attr.name, dev_idx))
 			return;
 
-		struct bch_member *m = bch2_members_v2_get_mut(sb, dev_idx);
-
-		const struct bch_dev_sb_opt_set *set = bch2_dev_sb_opt_setters + id;
-		if (set->set_sb)
-			set->set_sb(m, v);
-		else
-			pr_err("option %s cannot be set via opt_set_sb()", opt->attr.name);
+		opt->set_member(bch2_members_v2_get_mut(sb, dev_idx), v);
 	}
 }
 
diff --git a/fs/bcachefs/opts.h b/fs/bcachefs/opts.h
index 9d397fc2a1f0..9a3102f30e11 100644
--- a/fs/bcachefs/opts.h
+++ b/fs/bcachefs/opts.h
@@ -16,6 +16,7 @@ extern const char * const bch2_version_upgrade_opts[];
 extern const char * const bch2_sb_features[];
 extern const char * const bch2_sb_compat[];
 extern const char * const __bch2_btree_ids[];
+extern const char * const __bch2_csum_types[];
 extern const char * const __bch2_csum_opts[];
 extern const char * const __bch2_compression_types[];
 extern const char * const bch2_compression_opts[];
@@ -50,10 +51,6 @@ static inline const char *bch2_d_type_str(unsigned d_type)
  * apply the options from that struct that are defined.
  */
 
-/* dummy option, for options that aren't stored in the superblock */
-u64 BCH2_NO_SB_OPT(const struct bch_sb *);
-void SET_BCH2_NO_SB_OPT(struct bch_sb *, u64);
-
 /* When can be set: */
 enum opt_flags {
 	OPT_FS			= BIT(0),	/* Filesystem option */
@@ -132,19 +129,24 @@ enum fsck_err_opts {
 	  OPT_FS|OPT_FORMAT|						\
 	  OPT_HUMAN_READABLE|OPT_MUST_BE_POW_2|OPT_SB_FIELD_SECTORS,	\
 	  OPT_UINT(512, 1U << 16),					\
-	  BCH_SB_BLOCK_SIZE,		8,				\
+	  BCH_SB_BLOCK_SIZE,		4 << 10,			\
 	  "size",	NULL)						\
 	x(btree_node_size,		u32,				\
 	  OPT_FS|OPT_FORMAT|						\
 	  OPT_HUMAN_READABLE|OPT_MUST_BE_POW_2|OPT_SB_FIELD_SECTORS,	\
 	  OPT_UINT(512, 1U << 20),					\
-	  BCH_SB_BTREE_NODE_SIZE,	512,				\
+	  BCH_SB_BTREE_NODE_SIZE,	256 << 10,			\
 	  "size",	"Btree node size, default 256k")		\
 	x(errors,			u8,				\
 	  OPT_FS|OPT_FORMAT|OPT_MOUNT|OPT_RUNTIME,			\
 	  OPT_STR(bch2_error_actions),					\
 	  BCH_SB_ERROR_ACTION,		BCH_ON_ERROR_fix_safe,		\
 	  NULL,		"Action to take on filesystem error")		\
+	x(write_error_timeout,		u16,				\
+	  OPT_FS|OPT_FORMAT|OPT_MOUNT|OPT_RUNTIME,			\
+	  OPT_UINT(1, 300),						\
+	  BCH_SB_WRITE_ERROR_TIMEOUT,	30,				\
+	  NULL,		"Number of consecutive write errors allowed before kicking out a device")\
 	x(metadata_replicas,		u8,				\
 	  OPT_FS|OPT_FORMAT|OPT_MOUNT|OPT_RUNTIME,			\
 	  OPT_UINT(1, BCH_REPLICAS_MAX),				\
@@ -181,6 +183,11 @@ enum fsck_err_opts {
 	  OPT_STR(__bch2_csum_opts),					\
 	  BCH_SB_DATA_CSUM_TYPE,	BCH_CSUM_OPT_crc32c,		\
 	  NULL,		NULL)						\
+	x(checksum_err_retry_nr,	u8,				\
+	  OPT_FS|OPT_FORMAT|OPT_MOUNT|OPT_RUNTIME,			\
+	  OPT_UINT(0, 32),						\
+	  BCH_SB_CSUM_ERR_RETRY_NR,	3,				\
+	  NULL,		NULL)						\
 	x(compression,			u8,				\
 	  OPT_FS|OPT_INODE|OPT_FORMAT|OPT_MOUNT|OPT_RUNTIME,		\
 	  OPT_FN(bch2_opt_compression),					\
@@ -197,7 +204,7 @@ enum fsck_err_opts {
 	  BCH_SB_STR_HASH_TYPE,		BCH_STR_HASH_OPT_siphash,	\
 	  NULL,		"Hash function for directory entries and xattrs")\
 	x(metadata_target,		u16,				\
-	  OPT_FS|OPT_INODE|OPT_FORMAT|OPT_MOUNT|OPT_RUNTIME,		\
+	  OPT_FS|OPT_FORMAT|OPT_MOUNT|OPT_RUNTIME,			\
 	  OPT_FN(bch2_opt_target),					\
 	  BCH_SB_METADATA_TARGET,	0,				\
 	  "(target)",	"Device or label for metadata writes")		\
@@ -308,11 +315,6 @@ enum fsck_err_opts {
 	  OPT_BOOL(),							\
 	  BCH2_NO_SB_OPT,		false,				\
 	  NULL,		"Don't kick drives out when splitbrain detected")\
-	x(discard,			u8,				\
-	  OPT_FS|OPT_MOUNT|OPT_DEVICE,					\
-	  OPT_BOOL(),							\
-	  BCH2_NO_SB_OPT,		true,				\
-	  NULL,		"Enable discard/TRIM support")			\
 	x(verbose,			u8,				\
 	  OPT_FS|OPT_MOUNT|OPT_RUNTIME,					\
 	  OPT_BOOL(),							\
@@ -493,27 +495,32 @@ enum fsck_err_opts {
 	  BCH2_NO_SB_OPT,		false,				\
 	  NULL,		"Skip submit_bio() for data reads and writes, "	\
 			"for performance testing purposes")		\
-	x(fs_size,			u64,				\
-	  OPT_DEVICE,							\
+	x(state,			u64,				\
+	  OPT_DEVICE|OPT_RUNTIME,					\
+	  OPT_STR(bch2_member_states),					\
+	  BCH_MEMBER_STATE,		BCH_MEMBER_STATE_rw,		\
+	  "state",	"rw,ro,failed,spare")				\
+	x(bucket_size,			u32,				\
+	  OPT_DEVICE|OPT_HUMAN_READABLE|OPT_SB_FIELD_SECTORS,		\
 	  OPT_UINT(0, S64_MAX),						\
-	  BCH2_NO_SB_OPT,		0,				\
-	  "size",	"Size of filesystem on device")			\
-	x(bucket,			u32,				\
-	  OPT_DEVICE,							\
-	  OPT_UINT(0, S64_MAX),						\
-	  BCH2_NO_SB_OPT,		0,				\
+	  BCH_MEMBER_BUCKET_SIZE,	0,				\
 	  "size",	"Specifies the bucket size; must be greater than the btree node size")\
 	x(durability,			u8,				\
-	  OPT_DEVICE|OPT_SB_FIELD_ONE_BIAS,				\
+	  OPT_DEVICE|OPT_RUNTIME|OPT_SB_FIELD_ONE_BIAS,			\
 	  OPT_UINT(0, BCH_REPLICAS_MAX),				\
-	  BCH2_NO_SB_OPT,		1,				\
+	  BCH_MEMBER_DURABILITY,	1,				\
 	  "n",		"Data written to this device will be considered\n"\
 			"to have already been replicated n times")	\
 	x(data_allowed,			u8,				\
 	  OPT_DEVICE,							\
 	  OPT_BITFIELD(__bch2_data_types),				\
-	  BCH2_NO_SB_OPT,		BIT(BCH_DATA_journal)|BIT(BCH_DATA_btree)|BIT(BCH_DATA_user),\
+	  BCH_MEMBER_DATA_ALLOWED,	BIT(BCH_DATA_journal)|BIT(BCH_DATA_btree)|BIT(BCH_DATA_user),\
 	  "types",	"Allowed data types for this device: journal, btree, and/or user")\
+	x(discard,			u8,				\
+	  OPT_MOUNT|OPT_DEVICE|OPT_RUNTIME,				\
+	  OPT_BOOL(),							\
+	  BCH_MEMBER_DISCARD,		true,				\
+	  NULL,		"Enable discard/TRIM support")			\
 	x(btree_node_prefetch,		u8,				\
 	  OPT_FS|OPT_MOUNT|OPT_RUNTIME,					\
 	  OPT_BOOL(),							\
@@ -521,11 +528,6 @@ enum fsck_err_opts {
 	  NULL,		"BTREE_ITER_prefetch casuse btree nodes to be\n"\
 	  " prefetched sequentially")
 
-#define BCH_DEV_OPT_SETTERS()						\
-	x(discard,		BCH_MEMBER_DISCARD)			\
-	x(durability,		BCH_MEMBER_DURABILITY)			\
-	x(data_allowed,		BCH_MEMBER_DATA_ALLOWED)
-
 struct bch_opts {
 #define x(_name, _bits, ...)	unsigned _name##_defined:1;
 	BCH_OPTS()
@@ -582,8 +584,6 @@ struct printbuf;
 
 struct bch_option {
 	struct attribute	attr;
-	u64			(*get_sb)(const struct bch_sb *);
-	void			(*set_sb)(struct bch_sb *, u64);
 	enum opt_type		type;
 	enum opt_flags		flags;
 	u64			min, max;
@@ -595,6 +595,12 @@ struct bch_option {
 	const char		*hint;
 	const char		*help;
 
+	u64			(*get_sb)(const struct bch_sb *);
+	void			(*set_sb)(struct bch_sb *, u64);
+
+	u64			(*get_member)(const struct bch_member *);
+	void			(*set_member)(struct bch_member *, u64);
+
 };
 
 extern const struct bch_option bch2_opt_table[];
@@ -603,7 +609,7 @@ bool bch2_opt_defined_by_id(const struct bch_opts *, enum bch_opt_id);
 u64 bch2_opt_get_by_id(const struct bch_opts *, enum bch_opt_id);
 void bch2_opt_set_by_id(struct bch_opts *, enum bch_opt_id, u64);
 
-u64 bch2_opt_from_sb(struct bch_sb *, enum bch_opt_id);
+u64 bch2_opt_from_sb(struct bch_sb *, enum bch_opt_id, int);
 int bch2_opts_from_sb(struct bch_opts *, struct bch_sb *);
 void __bch2_opt_set_sb(struct bch_sb *, int, const struct bch_option *, u64);
 
@@ -625,7 +631,7 @@ void bch2_opts_to_text(struct printbuf *,
 		       struct bch_fs *, struct bch_sb *,
 		       unsigned, unsigned, unsigned);
 
-int bch2_opt_check_may_set(struct bch_fs *, int, u64);
+int bch2_opt_check_may_set(struct bch_fs *, struct bch_dev *, int, u64);
 int bch2_opts_check_may_set(struct bch_fs *);
 int bch2_parse_one_mount_opt(struct bch_fs *, struct bch_opts *,
 			     struct printbuf *, const char *, const char *);
diff --git a/fs/bcachefs/progress.c b/fs/bcachefs/progress.c
new file mode 100644
index 000000000000..bafd1c91a802
--- /dev/null
+++ b/fs/bcachefs/progress.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "bcachefs.h"
+#include "bbpos.h"
+#include "disk_accounting.h"
+#include "progress.h"
+
+void bch2_progress_init(struct progress_indicator_state *s,
+			struct bch_fs *c,
+			u64 btree_id_mask)
+{
+	memset(s, 0, sizeof(*s));
+
+	s->next_print = jiffies + HZ * 10;
+
+	for (unsigned i = 0; i < BTREE_ID_NR; i++) {
+		if (!(btree_id_mask & BIT_ULL(i)))
+			continue;
+
+		struct disk_accounting_pos acc = {
+			.type		= BCH_DISK_ACCOUNTING_btree,
+			.btree.id	= i,
+		};
+
+		u64 v;
+		bch2_accounting_mem_read(c, disk_accounting_pos_to_bpos(&acc), &v, 1);
+		s->nodes_total += div64_ul(v, btree_sectors(c));
+	}
+}
+
+static inline bool progress_update_p(struct progress_indicator_state *s)
+{
+	bool ret = time_after_eq(jiffies, s->next_print);
+
+	if (ret)
+		s->next_print = jiffies + HZ * 10;
+	return ret;
+}
+
+void bch2_progress_update_iter(struct btree_trans *trans,
+			       struct progress_indicator_state *s,
+			       struct btree_iter *iter,
+			       const char *msg)
+{
+	struct bch_fs *c = trans->c;
+	struct btree *b = path_l(btree_iter_path(trans, iter))->b;
+
+	s->nodes_seen += b != s->last_node;
+	s->last_node = b;
+
+	if (progress_update_p(s)) {
+		struct printbuf buf = PRINTBUF;
+		unsigned percent = s->nodes_total
+			? div64_u64(s->nodes_seen * 100, s->nodes_total)
+			: 0;
+
+		prt_printf(&buf, "%s: %d%%, done %llu/%llu nodes, at ",
+			   msg, percent, s->nodes_seen, s->nodes_total);
+		bch2_bbpos_to_text(&buf, BBPOS(iter->btree_id, iter->pos));
+
+		bch_info(c, "%s", buf.buf);
+		printbuf_exit(&buf);
+	}
+}
diff --git a/fs/bcachefs/progress.h b/fs/bcachefs/progress.h
new file mode 100644
index 000000000000..23fb1811f943
--- /dev/null
+++ b/fs/bcachefs/progress.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _BCACHEFS_PROGRESS_H
+#define _BCACHEFS_PROGRESS_H
+
+/*
+ * Lame progress indicators
+ *
+ * We don't like to use these because they print to the dmesg console, which is
+ * spammy - we much prefer to be wired up to a userspace programm (e.g. via
+ * thread_with_file) and have it print the progress indicator.
+ *
+ * But some code is old and doesn't support that, or runs in a context where
+ * that's not yet practical (mount).
+ */
+
+struct progress_indicator_state {
+	unsigned long		next_print;
+	u64			nodes_seen;
+	u64			nodes_total;
+	struct btree		*last_node;
+};
+
+void bch2_progress_init(struct progress_indicator_state *, struct bch_fs *, u64);
+void bch2_progress_update_iter(struct btree_trans *,
+			       struct progress_indicator_state *,
+			       struct btree_iter *,
+			       const char *);
+
+#endif /* _BCACHEFS_PROGRESS_H */
diff --git a/fs/bcachefs/rebalance.c b/fs/bcachefs/rebalance.c
index d0a1f5cd5c2b..10c6a7fda54c 100644
--- a/fs/bcachefs/rebalance.c
+++ b/fs/bcachefs/rebalance.c
@@ -26,9 +26,8 @@
 
 /* bch_extent_rebalance: */
 
-static const struct bch_extent_rebalance *bch2_bkey_rebalance_opts(struct bkey_s_c k)
+static const struct bch_extent_rebalance *bch2_bkey_ptrs_rebalance_opts(struct bkey_ptrs_c ptrs)
 {
-	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 	const union bch_extent_entry *entry;
 
 	bkey_extent_entry_for_each(ptrs, entry)
@@ -38,6 +37,11 @@ static const struct bch_extent_rebalance *bch2_bkey_rebalance_opts(struct bkey_s
 	return NULL;
 }
 
+static const struct bch_extent_rebalance *bch2_bkey_rebalance_opts(struct bkey_s_c k)
+{
+	return bch2_bkey_ptrs_rebalance_opts(bch2_bkey_ptrs_c(k));
+}
+
 static inline unsigned bch2_bkey_ptrs_need_compress(struct bch_fs *c,
 					   struct bch_io_opts *opts,
 					   struct bkey_s_c k,
@@ -91,17 +95,24 @@ static unsigned bch2_bkey_ptrs_need_rebalance(struct bch_fs *c,
 {
 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 
+	if (bch2_bkey_extent_ptrs_flags(ptrs) & BIT_ULL(BCH_EXTENT_FLAG_poisoned))
+		return 0;
+
 	return bch2_bkey_ptrs_need_compress(c, opts, k, ptrs) |
 		bch2_bkey_ptrs_need_move(c, opts, ptrs);
 }
 
 u64 bch2_bkey_sectors_need_rebalance(struct bch_fs *c, struct bkey_s_c k)
 {
-	const struct bch_extent_rebalance *opts = bch2_bkey_rebalance_opts(k);
+	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+
+	const struct bch_extent_rebalance *opts = bch2_bkey_ptrs_rebalance_opts(ptrs);
 	if (!opts)
 		return 0;
 
-	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+	if (bch2_bkey_extent_ptrs_flags(ptrs) & BIT_ULL(BCH_EXTENT_FLAG_poisoned))
+		return 0;
+
 	const union bch_extent_entry *entry;
 	struct extent_ptr_decoded p;
 	u64 sectors = 0;
@@ -341,7 +352,7 @@ static struct bkey_s_c next_rebalance_extent(struct btree_trans *trans,
 	memset(data_opts, 0, sizeof(*data_opts));
 	data_opts->rewrite_ptrs		= bch2_bkey_ptrs_need_rebalance(c, io_opts, k);
 	data_opts->target		= io_opts->background_target;
-	data_opts->write_flags		|= BCH_WRITE_ONLY_SPECIFIED_DEVS;
+	data_opts->write_flags		|= BCH_WRITE_only_specified_devs;
 
 	if (!data_opts->rewrite_ptrs) {
 		/*
@@ -449,7 +460,7 @@ static bool rebalance_pred(struct bch_fs *c, void *arg,
 {
 	data_opts->rewrite_ptrs		= bch2_bkey_ptrs_need_rebalance(c, io_opts, k);
 	data_opts->target		= io_opts->background_target;
-	data_opts->write_flags		|= BCH_WRITE_ONLY_SPECIFIED_DEVS;
+	data_opts->write_flags		|= BCH_WRITE_only_specified_devs;
 	return data_opts->rewrite_ptrs != 0;
 }
 
@@ -590,8 +601,19 @@ static int bch2_rebalance_thread(void *arg)
 
 void bch2_rebalance_status_to_text(struct printbuf *out, struct bch_fs *c)
 {
+	printbuf_tabstop_push(out, 32);
+
 	struct bch_fs_rebalance *r = &c->rebalance;
 
+	/* print pending work */
+	struct disk_accounting_pos acc = { .type = BCH_DISK_ACCOUNTING_rebalance_work, };
+	u64 v;
+	bch2_accounting_mem_read(c, disk_accounting_pos_to_bpos(&acc), &v, 1);
+
+	prt_printf(out, "pending work:\t");
+	prt_human_readable_u64(out, v);
+	prt_printf(out, "\n\n");
+
 	prt_str(out, bch2_rebalance_state_strs[r->state]);
 	prt_newline(out);
 	printbuf_indent_add(out, 2);
@@ -600,15 +622,15 @@ void bch2_rebalance_status_to_text(struct printbuf *out, struct bch_fs *c)
 	case BCH_REBALANCE_waiting: {
 		u64 now = atomic64_read(&c->io_clock[WRITE].now);
 
-		prt_str(out, "io wait duration:  ");
+		prt_printf(out, "io wait duration:\t");
 		bch2_prt_human_readable_s64(out, (r->wait_iotime_end - r->wait_iotime_start) << 9);
 		prt_newline(out);
 
-		prt_str(out, "io wait remaining: ");
+		prt_printf(out, "io wait remaining:\t");
 		bch2_prt_human_readable_s64(out, (r->wait_iotime_end - now) << 9);
 		prt_newline(out);
 
-		prt_str(out, "duration waited:   ");
+		prt_printf(out, "duration waited:\t");
 		bch2_pr_time_units(out, ktime_get_real_ns() - r->wait_wallclock_start);
 		prt_newline(out);
 		break;
@@ -621,6 +643,18 @@ void bch2_rebalance_status_to_text(struct printbuf *out, struct bch_fs *c)
 		break;
 	}
 	prt_newline(out);
+
+	rcu_read_lock();
+	struct task_struct *t = rcu_dereference(c->rebalance.thread);
+	if (t)
+		get_task_struct(t);
+	rcu_read_unlock();
+
+	if (t) {
+		bch2_prt_task_backtrace(out, t, 0, GFP_KERNEL);
+		put_task_struct(t);
+	}
+
 	printbuf_indent_sub(out, 2);
 }
 
diff --git a/fs/bcachefs/recovery.c b/fs/bcachefs/recovery.c
index 71c786cdb192..266c5770c824 100644
--- a/fs/bcachefs/recovery.c
+++ b/fs/bcachefs/recovery.c
@@ -13,12 +13,12 @@
 #include "disk_accounting.h"
 #include "errcode.h"
 #include "error.h"
-#include "fs-common.h"
 #include "journal_io.h"
 #include "journal_reclaim.h"
 #include "journal_seq_blacklist.h"
 #include "logged_ops.h"
 #include "move.h"
+#include "namei.h"
 #include "quota.h"
 #include "rebalance.h"
 #include "recovery.h"
@@ -899,7 +899,7 @@ int bch2_fs_recovery(struct bch_fs *c)
 	 * journal sequence numbers:
 	 */
 	if (!c->sb.clean)
-		journal_seq += 8;
+		journal_seq += JOURNAL_BUF_NR * 4;
 
 	if (blacklist_seq != journal_seq) {
 		ret =   bch2_journal_log_msg(c, "blacklisting entries %llu-%llu",
diff --git a/fs/bcachefs/recovery_passes_types.h b/fs/bcachefs/recovery_passes_types.h
index 418557960ed6..e89b9c783285 100644
--- a/fs/bcachefs/recovery_passes_types.h
+++ b/fs/bcachefs/recovery_passes_types.h
@@ -24,7 +24,7 @@
 	x(check_topology,			 4, 0)					\
 	x(accounting_read,			39, PASS_ALWAYS)			\
 	x(alloc_read,				 0, PASS_ALWAYS)			\
-	x(stripes_read,				 1, PASS_ALWAYS)			\
+	x(stripes_read,				 1, 0)					\
 	x(initialize_subvolumes,		 2, 0)					\
 	x(snapshots_read,			 3, PASS_ALWAYS)			\
 	x(check_allocations,			 5, PASS_FSCK)				\
diff --git a/fs/bcachefs/reflink.c b/fs/bcachefs/reflink.c
index 441e648f28b5..68172c6eba21 100644
--- a/fs/bcachefs/reflink.c
+++ b/fs/bcachefs/reflink.c
@@ -185,12 +185,21 @@ static int bch2_indirect_extent_missing_error(struct btree_trans *trans,
 	BUG_ON(missing_start	< refd_start);
 	BUG_ON(missing_end	> refd_end);
 
-	if (fsck_err(trans, reflink_p_to_missing_reflink_v,
-		     "pointer to missing indirect extent\n"
-		     "  %s\n"
-		     "  missing range %llu-%llu",
-		     (bch2_bkey_val_to_text(&buf, c, p.s_c), buf.buf),
-		     missing_start, missing_end)) {
+	struct bpos missing_pos = bkey_start_pos(p.k);
+	missing_pos.offset += missing_start - live_start;
+
+	prt_printf(&buf, "pointer to missing indirect extent in ");
+	ret = bch2_inum_snap_offset_err_msg_trans(trans, &buf, missing_pos);
+	if (ret)
+		goto err;
+
+	prt_printf(&buf, "-%llu\n  ", (missing_pos.offset + (missing_end - missing_start)) << 9);
+	bch2_bkey_val_to_text(&buf, c, p.s_c);
+
+	prt_printf(&buf, "\n  missing reflink btree range %llu-%llu",
+		   missing_start, missing_end);
+
+	if (fsck_err(trans, reflink_p_to_missing_reflink_v, "%s", buf.buf)) {
 		struct bkey_i_reflink_p *new = bch2_bkey_make_mut_noupdate_typed(trans, p.s_c, reflink_p);
 		ret = PTR_ERR_OR_ZERO(new);
 		if (ret)
@@ -597,7 +606,7 @@ s64 bch2_remap_range(struct bch_fs *c,
 	u64 dst_done = 0;
 	u32 dst_snapshot, src_snapshot;
 	bool reflink_p_may_update_opts_field =
-		bch2_request_incompat_feature(c, bcachefs_metadata_version_reflink_p_may_update_opts);
+		!bch2_request_incompat_feature(c, bcachefs_metadata_version_reflink_p_may_update_opts);
 	int ret = 0, ret2 = 0;
 
 	if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_reflink))
diff --git a/fs/bcachefs/sb-counters.c b/fs/bcachefs/sb-counters.c
index 6992e7469112..2b4b8445d418 100644
--- a/fs/bcachefs/sb-counters.c
+++ b/fs/bcachefs/sb-counters.c
@@ -5,7 +5,13 @@
 
 /* BCH_SB_FIELD_counters */
 
-static const char * const bch2_counter_names[] = {
+static const u8 counters_to_stable_map[] = {
+#define x(n, id, ...)	[BCH_COUNTER_##n] = BCH_COUNTER_STABLE_##n,
+	BCH_PERSISTENT_COUNTERS()
+#undef x
+};
+
+const char * const bch2_counter_names[] = {
 #define x(t, n, ...) (#t),
 	BCH_PERSISTENT_COUNTERS()
 #undef x
@@ -18,13 +24,13 @@ static size_t bch2_sb_counter_nr_entries(struct bch_sb_field_counters *ctrs)
 		return 0;
 
 	return (__le64 *) vstruct_end(&ctrs->field) - &ctrs->d[0];
-};
+}
 
 static int bch2_sb_counters_validate(struct bch_sb *sb, struct bch_sb_field *f,
 				enum bch_validate_flags flags, struct printbuf *err)
 {
 	return 0;
-};
+}
 
 static void bch2_sb_counters_to_text(struct printbuf *out, struct bch_sb *sb,
 			      struct bch_sb_field *f)
@@ -32,50 +38,56 @@ static void bch2_sb_counters_to_text(struct printbuf *out, struct bch_sb *sb,
 	struct bch_sb_field_counters *ctrs = field_to_type(f, counters);
 	unsigned int nr = bch2_sb_counter_nr_entries(ctrs);
 
-	for (unsigned i = 0; i < nr; i++)
-		prt_printf(out, "%s \t%llu\n",
-			   i < BCH_COUNTER_NR ? bch2_counter_names[i] : "(unknown)",
-			   le64_to_cpu(ctrs->d[i]));
-};
+	for (unsigned i = 0; i < BCH_COUNTER_NR; i++) {
+		unsigned stable = counters_to_stable_map[i];
+		if (stable < nr)
+			prt_printf(out, "%s \t%llu\n",
+				   bch2_counter_names[i],
+				   le64_to_cpu(ctrs->d[stable]));
+	}
+}
 
 int bch2_sb_counters_to_cpu(struct bch_fs *c)
 {
 	struct bch_sb_field_counters *ctrs = bch2_sb_field_get(c->disk_sb.sb, counters);
-	unsigned int i;
 	unsigned int nr = bch2_sb_counter_nr_entries(ctrs);
-	u64 val = 0;
 
-	for (i = 0; i < BCH_COUNTER_NR; i++)
+	for (unsigned i = 0; i < BCH_COUNTER_NR; i++)
 		c->counters_on_mount[i] = 0;
 
-	for (i = 0; i < min_t(unsigned int, nr, BCH_COUNTER_NR); i++) {
-		val = le64_to_cpu(ctrs->d[i]);
-		percpu_u64_set(&c->counters[i], val);
-		c->counters_on_mount[i] = val;
+	for (unsigned i = 0; i < BCH_COUNTER_NR; i++) {
+		unsigned stable = counters_to_stable_map[i];
+		if (stable < nr) {
+			u64 v = le64_to_cpu(ctrs->d[stable]);
+			percpu_u64_set(&c->counters[i], v);
+			c->counters_on_mount[i] = v;
+		}
 	}
+
 	return 0;
-};
+}
 
 int bch2_sb_counters_from_cpu(struct bch_fs *c)
 {
 	struct bch_sb_field_counters *ctrs = bch2_sb_field_get(c->disk_sb.sb, counters);
 	struct bch_sb_field_counters *ret;
-	unsigned int i;
 	unsigned int nr = bch2_sb_counter_nr_entries(ctrs);
 
 	if (nr < BCH_COUNTER_NR) {
 		ret = bch2_sb_field_resize(&c->disk_sb, counters,
-					       sizeof(*ctrs) / sizeof(u64) + BCH_COUNTER_NR);
-
+					   sizeof(*ctrs) / sizeof(u64) + BCH_COUNTER_NR);
 		if (ret) {
 			ctrs = ret;
 			nr = bch2_sb_counter_nr_entries(ctrs);
 		}
 	}
 
+	for (unsigned i = 0; i < BCH_COUNTER_NR; i++) {
+		unsigned stable = counters_to_stable_map[i];
+		if (stable < nr)
+			ctrs->d[stable] = cpu_to_le64(percpu_u64_get(&c->counters[i]));
+	}
 
-	for (i = 0; i < min_t(unsigned int, nr, BCH_COUNTER_NR); i++)
-		ctrs->d[i] = cpu_to_le64(percpu_u64_get(&c->counters[i]));
 	return 0;
 }
 
@@ -97,3 +109,39 @@ const struct bch_sb_field_ops bch_sb_field_ops_counters = {
 	.validate	= bch2_sb_counters_validate,
 	.to_text	= bch2_sb_counters_to_text,
 };
+
+#ifndef NO_BCACHEFS_CHARDEV
+long bch2_ioctl_query_counters(struct bch_fs *c,
+			struct bch_ioctl_query_counters __user *user_arg)
+{
+	struct bch_ioctl_query_counters arg;
+	int ret = copy_from_user_errcode(&arg, user_arg, sizeof(arg));
+	if (ret)
+		return ret;
+
+	if ((arg.flags & ~BCH_IOCTL_QUERY_COUNTERS_MOUNT) ||
+	    arg.pad)
+		return -EINVAL;
+
+	arg.nr = min(arg.nr, BCH_COUNTER_NR);
+	ret = put_user(arg.nr, &user_arg->nr);
+	if (ret)
+		return ret;
+
+	for (unsigned i = 0; i < BCH_COUNTER_NR; i++) {
+		unsigned stable = counters_to_stable_map[i];
+
+		if (stable < arg.nr) {
+			u64 v = !(arg.flags & BCH_IOCTL_QUERY_COUNTERS_MOUNT)
+				? percpu_u64_get(&c->counters[i])
+				: c->counters_on_mount[i];
+
+			ret = put_user(v, &user_arg->d[stable]);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+#endif
diff --git a/fs/bcachefs/sb-counters.h b/fs/bcachefs/sb-counters.h
index 81f8aec9fcb1..a4329ad8dd1b 100644
--- a/fs/bcachefs/sb-counters.h
+++ b/fs/bcachefs/sb-counters.h
@@ -11,6 +11,10 @@ int bch2_sb_counters_from_cpu(struct bch_fs *);
 void bch2_fs_counters_exit(struct bch_fs *);
 int bch2_fs_counters_init(struct bch_fs *);
 
+extern const char * const bch2_counter_names[];
 extern const struct bch_sb_field_ops bch_sb_field_ops_counters;
 
+long bch2_ioctl_query_counters(struct bch_fs *,
+			struct bch_ioctl_query_counters __user *);
+
 #endif // _BCACHEFS_SB_COUNTERS_H
diff --git a/fs/bcachefs/sb-counters_format.h b/fs/bcachefs/sb-counters_format.h
index fdcf598f08b1..5c4e5de79d81 100644
--- a/fs/bcachefs/sb-counters_format.h
+++ b/fs/bcachefs/sb-counters_format.h
@@ -9,10 +9,25 @@ enum counters_flags {
 
 #define BCH_PERSISTENT_COUNTERS()					\
 	x(io_read,					0,	TYPE_SECTORS)	\
+	x(io_read_inline,				80,	TYPE_SECTORS)	\
+	x(io_read_hole,					81,	TYPE_SECTORS)	\
+	x(io_read_promote,				30,	TYPE_COUNTER)	\
+	x(io_read_bounce,				31,	TYPE_COUNTER)	\
+	x(io_read_split,				33,	TYPE_COUNTER)	\
+	x(io_read_reuse_race,				34,	TYPE_COUNTER)	\
+	x(io_read_retry,				32,	TYPE_COUNTER)	\
+	x(io_read_fail_and_poison,			82,	TYPE_COUNTER)	\
 	x(io_write,					1,	TYPE_SECTORS)	\
 	x(io_move,					2,	TYPE_SECTORS)	\
+	x(io_move_read,					35,	TYPE_SECTORS)	\
+	x(io_move_write,				36,	TYPE_SECTORS)	\
+	x(io_move_finish,				37,	TYPE_SECTORS)	\
+	x(io_move_fail,					38,	TYPE_COUNTER)	\
+	x(io_move_write_fail,				82,	TYPE_COUNTER)	\
+	x(io_move_start_fail,				39,	TYPE_COUNTER)	\
 	x(bucket_invalidate,				3,	TYPE_COUNTER)	\
 	x(bucket_discard,				4,	TYPE_COUNTER)	\
+	x(bucket_discard_fast,				79,	TYPE_COUNTER)	\
 	x(bucket_alloc,					5,	TYPE_COUNTER)	\
 	x(bucket_alloc_fail,				6,	TYPE_COUNTER)	\
 	x(btree_cache_scan,				7,	TYPE_COUNTER)	\
@@ -38,16 +53,6 @@ enum counters_flags {
 	x(journal_reclaim_finish,			27,	TYPE_COUNTER)	\
 	x(journal_reclaim_start,			28,	TYPE_COUNTER)	\
 	x(journal_write,				29,	TYPE_COUNTER)	\
-	x(read_promote,					30,	TYPE_COUNTER)	\
-	x(read_bounce,					31,	TYPE_COUNTER)	\
-	x(read_split,					33,	TYPE_COUNTER)	\
-	x(read_retry,					32,	TYPE_COUNTER)	\
-	x(read_reuse_race,				34,	TYPE_COUNTER)	\
-	x(move_extent_read,				35,	TYPE_SECTORS)	\
-	x(move_extent_write,				36,	TYPE_SECTORS)	\
-	x(move_extent_finish,				37,	TYPE_SECTORS)	\
-	x(move_extent_fail,				38,	TYPE_COUNTER)	\
-	x(move_extent_start_fail,			39,	TYPE_COUNTER)	\
 	x(copygc,					40,	TYPE_COUNTER)	\
 	x(copygc_wait,					41,	TYPE_COUNTER)	\
 	x(gc_gens_end,					42,	TYPE_COUNTER)	\
@@ -95,6 +100,13 @@ enum bch_persistent_counters {
 	BCH_COUNTER_NR
 };
 
+enum bch_persistent_counters_stable {
+#define x(t, n, ...) BCH_COUNTER_STABLE_##t = n,
+	BCH_PERSISTENT_COUNTERS()
+#undef x
+	BCH_COUNTER_STABLE_NR
+};
+
 struct bch_sb_field_counters {
 	struct bch_sb_field	field;
 	__le64			d[];
diff --git a/fs/bcachefs/sb-downgrade.c b/fs/bcachefs/sb-downgrade.c
index 051214fdc735..acb5d845841e 100644
--- a/fs/bcachefs/sb-downgrade.c
+++ b/fs/bcachefs/sb-downgrade.c
@@ -90,7 +90,13 @@
 	  BIT_ULL(BCH_RECOVERY_PASS_check_allocations),		\
 	  BCH_FSCK_ERR_accounting_mismatch,			\
 	  BCH_FSCK_ERR_accounting_key_replicas_nr_devs_0,	\
-	  BCH_FSCK_ERR_accounting_key_junk_at_end)
+	  BCH_FSCK_ERR_accounting_key_junk_at_end)		\
+	x(cached_backpointers,					\
+	  BIT_ULL(BCH_RECOVERY_PASS_check_extents_to_backpointers),\
+	  BCH_FSCK_ERR_ptr_to_missing_backpointer)		\
+	x(stripe_backpointers,					\
+	  BIT_ULL(BCH_RECOVERY_PASS_check_extents_to_backpointers),\
+	  BCH_FSCK_ERR_ptr_to_missing_backpointer)
 
 #define DOWNGRADE_TABLE()					\
 	x(bucket_stripe_sectors,				\
diff --git a/fs/bcachefs/sb-errors_format.h b/fs/bcachefs/sb-errors_format.h
index b86ec013d7d7..1736abea9ed1 100644
--- a/fs/bcachefs/sb-errors_format.h
+++ b/fs/bcachefs/sb-errors_format.h
@@ -179,6 +179,7 @@ enum bch_fsck_flags {
 	x(ptr_crc_redundant,					160,	0)		\
 	x(ptr_crc_nonce_mismatch,				162,	0)		\
 	x(ptr_stripe_redundant,					163,	0)		\
+	x(extent_flags_not_at_start,				306,	0)		\
 	x(reservation_key_nr_replicas_invalid,			164,	0)		\
 	x(reflink_v_refcount_wrong,				165,	FSCK_AUTOFIX)	\
 	x(reflink_v_pos_bad,					292,	0)		\
@@ -310,11 +311,14 @@ enum bch_fsck_flags {
 	x(accounting_key_replicas_nr_required_bad,		279,	FSCK_AUTOFIX)	\
 	x(accounting_key_replicas_devs_unsorted,		280,	FSCK_AUTOFIX)	\
 	x(accounting_key_version_0,				282,	FSCK_AUTOFIX)	\
+	x(accounting_key_nr_counters_wrong,			307,	FSCK_AUTOFIX)	\
 	x(logged_op_but_clean,					283,	FSCK_AUTOFIX)	\
 	x(compression_opt_not_marked_in_sb,			295,	FSCK_AUTOFIX)	\
 	x(compression_type_not_marked_in_sb,			296,	FSCK_AUTOFIX)	\
 	x(directory_size_mismatch,				303,	FSCK_AUTOFIX)	\
-	x(MAX,							304,	0)
+	x(dirent_cf_name_too_big,				304,	0)		\
+	x(dirent_stray_data_after_cf_name,			305,	0)		\
+	x(MAX,							308,	0)
 
 enum bch_sb_error_id {
 #define x(t, n, ...) BCH_FSCK_ERR_##t = n,
diff --git a/fs/bcachefs/sb-members.h b/fs/bcachefs/sb-members.h
index 762083b564ee..38261638a611 100644
--- a/fs/bcachefs/sb-members.h
+++ b/fs/bcachefs/sb-members.h
@@ -23,7 +23,19 @@ static inline bool bch2_dev_is_online(struct bch_dev *ca)
 	return !percpu_ref_is_zero(&ca->io_ref);
 }
 
-static inline bool bch2_dev_is_readable(struct bch_dev *ca)
+static inline struct bch_dev *bch2_dev_rcu(struct bch_fs *, unsigned);
+
+static inline bool bch2_dev_idx_is_online(struct bch_fs *c, unsigned dev)
+{
+	rcu_read_lock();
+	struct bch_dev *ca = bch2_dev_rcu(c, dev);
+	bool ret = ca && bch2_dev_is_online(ca);
+	rcu_read_unlock();
+
+	return ret;
+}
+
+static inline bool bch2_dev_is_healthy(struct bch_dev *ca)
 {
 	return bch2_dev_is_online(ca) &&
 		ca->mi.state != BCH_MEMBER_STATE_failed;
@@ -271,6 +283,8 @@ static inline struct bch_dev *bch2_dev_iterate(struct bch_fs *c, struct bch_dev
 
 static inline struct bch_dev *bch2_dev_get_ioref(struct bch_fs *c, unsigned dev, int rw)
 {
+	might_sleep();
+
 	rcu_read_lock();
 	struct bch_dev *ca = bch2_dev_rcu(c, dev);
 	if (ca && !percpu_ref_tryget(&ca->io_ref))
diff --git a/fs/bcachefs/sb-members_format.h b/fs/bcachefs/sb-members_format.h
index 2adf1221a440..3affec823b3f 100644
--- a/fs/bcachefs/sb-members_format.h
+++ b/fs/bcachefs/sb-members_format.h
@@ -79,6 +79,7 @@ struct bch_member {
 
 #define BCH_MEMBER_V1_BYTES	56
 
+LE16_BITMASK(BCH_MEMBER_BUCKET_SIZE,	struct bch_member, bucket_size,  0, 16)
 LE64_BITMASK(BCH_MEMBER_STATE,		struct bch_member, flags,  0,  4)
 /* 4-14 unused, was TIER, HAS_(META)DATA, REPLACEMENT */
 LE64_BITMASK(BCH_MEMBER_DISCARD,	struct bch_member, flags, 14, 15)
diff --git a/fs/bcachefs/snapshot.c b/fs/bcachefs/snapshot.c
index c54091a28909..e7f197896db1 100644
--- a/fs/bcachefs/snapshot.c
+++ b/fs/bcachefs/snapshot.c
@@ -146,8 +146,9 @@ bool __bch2_snapshot_is_ancestor(struct bch_fs *c, u32 id, u32 ancestor)
 		goto out;
 	}
 
-	while (id && id < ancestor - IS_ANCESTOR_BITMAP)
-		id = get_ancestor_below(t, id, ancestor);
+	if (likely(ancestor >= IS_ANCESTOR_BITMAP))
+		while (id && id < ancestor - IS_ANCESTOR_BITMAP)
+			id = get_ancestor_below(t, id, ancestor);
 
 	ret = id && id < ancestor
 		? test_ancestor_bitmap(t, id, ancestor)
@@ -389,7 +390,7 @@ static u32 bch2_snapshot_tree_next(struct bch_fs *c, u32 id)
 	return 0;
 }
 
-static u32 bch2_snapshot_tree_oldest_subvol(struct bch_fs *c, u32 snapshot_root)
+u32 bch2_snapshot_tree_oldest_subvol(struct bch_fs *c, u32 snapshot_root)
 {
 	u32 id = snapshot_root;
 	u32 subvol = 0, s;
diff --git a/fs/bcachefs/snapshot.h b/fs/bcachefs/snapshot.h
index 00373cf32e7b..81180181d7c9 100644
--- a/fs/bcachefs/snapshot.h
+++ b/fs/bcachefs/snapshot.h
@@ -105,6 +105,7 @@ static inline u32 bch2_snapshot_nth_parent(struct bch_fs *c, u32 id, u32 n)
 	return id;
 }
 
+u32 bch2_snapshot_tree_oldest_subvol(struct bch_fs *, u32);
 u32 bch2_snapshot_skiplist_get(struct bch_fs *, u32);
 
 static inline u32 bch2_snapshot_root(struct bch_fs *c, u32 id)
diff --git a/fs/bcachefs/str_hash.c b/fs/bcachefs/str_hash.c
index d78451c2a0c6..93e71119e5a4 100644
--- a/fs/bcachefs/str_hash.c
+++ b/fs/bcachefs/str_hash.c
@@ -50,7 +50,7 @@ static noinline int fsck_rename_dirent(struct btree_trans *trans,
 	for (unsigned i = 0; i < 1000; i++) {
 		unsigned len = sprintf(new->v.d_name, "%.*s.fsck_renamed-%u",
 				       old_name.len, old_name.name, i);
-		unsigned u64s = BKEY_U64s + dirent_val_u64s(len);
+		unsigned u64s = BKEY_U64s + dirent_val_u64s(len, 0);
 
 		if (u64s > U8_MAX)
 			return -EINVAL;
diff --git a/fs/bcachefs/str_hash.h b/fs/bcachefs/str_hash.h
index 55a4ac7bf220..575ad1e03904 100644
--- a/fs/bcachefs/str_hash.h
+++ b/fs/bcachefs/str_hash.h
@@ -12,7 +12,6 @@
 #include "super.h"
 
 #include <linux/crc32c.h>
-#include <crypto/hash.h>
 #include <crypto/sha2.h>
 
 static inline enum bch_str_hash_type
@@ -34,6 +33,7 @@ bch2_str_hash_opt_to_type(struct bch_fs *c, enum bch_str_hash_opts opt)
 
 struct bch_hash_info {
 	u8			type;
+	struct unicode_map 	*cf_encoding;
 	/*
 	 * For crc32 or crc64 string hashes the first key value of
 	 * the siphash_key (k0) is used as the key.
@@ -47,17 +47,17 @@ bch2_hash_info_init(struct bch_fs *c, const struct bch_inode_unpacked *bi)
 	/* XXX ick */
 	struct bch_hash_info info = {
 		.type = INODE_STR_HASH(bi),
+#ifdef CONFIG_UNICODE
+		.cf_encoding = !!(bi->bi_flags & BCH_INODE_casefolded) ? c->cf_encoding : NULL,
+#endif
 		.siphash_key = { .k0 = bi->bi_hash_seed }
 	};
 
 	if (unlikely(info.type == BCH_STR_HASH_siphash_old)) {
-		SHASH_DESC_ON_STACK(desc, c->sha256);
 		u8 digest[SHA256_DIGEST_SIZE];
 
-		desc->tfm = c->sha256;
-
-		crypto_shash_digest(desc, (void *) &bi->bi_hash_seed,
-				    sizeof(bi->bi_hash_seed), digest);
+		sha256((const u8 *)&bi->bi_hash_seed,
+		       sizeof(bi->bi_hash_seed), digest);
 		memcpy(&info.siphash_key, digest, sizeof(info.siphash_key));
 	}
 
diff --git a/fs/bcachefs/super-io.c b/fs/bcachefs/super-io.c
index a81a7b6c0989..572b06bfa0b8 100644
--- a/fs/bcachefs/super-io.c
+++ b/fs/bcachefs/super-io.c
@@ -25,9 +25,6 @@
 #include <linux/sort.h>
 #include <linux/string_choices.h>
 
-static const struct blk_holder_ops bch2_sb_handle_bdev_ops = {
-};
-
 struct bch2_metadata_version {
 	u16		version;
 	const char	*name;
@@ -69,12 +66,14 @@ enum bcachefs_metadata_version bch2_latest_compatible_version(enum bcachefs_meta
 	return v;
 }
 
-bool bch2_set_version_incompat(struct bch_fs *c, enum bcachefs_metadata_version version)
+int bch2_set_version_incompat(struct bch_fs *c, enum bcachefs_metadata_version version)
 {
-	bool ret = (c->sb.features & BIT_ULL(BCH_FEATURE_incompat_version_field)) &&
-		   version <= c->sb.version_incompat_allowed;
+	int ret = ((c->sb.features & BIT_ULL(BCH_FEATURE_incompat_version_field)) &&
+		   version <= c->sb.version_incompat_allowed)
+		? 0
+		: -BCH_ERR_may_not_use_incompat_feature;
 
-	if (ret) {
+	if (!ret) {
 		mutex_lock(&c->sb_lock);
 		SET_BCH_SB_VERSION_INCOMPAT(c->disk_sb.sb,
 			max(BCH_SB_VERSION_INCOMPAT(c->disk_sb.sb), version));
@@ -366,39 +365,41 @@ static int bch2_sb_compatible(struct bch_sb *sb, struct printbuf *out)
 	return 0;
 }
 
-static int bch2_sb_validate(struct bch_sb_handle *disk_sb,
-			    enum bch_validate_flags flags, struct printbuf *out)
+int bch2_sb_validate(struct bch_sb *sb, u64 read_offset,
+		     enum bch_validate_flags flags, struct printbuf *out)
 {
-	struct bch_sb *sb = disk_sb->sb;
 	struct bch_sb_field_members_v1 *mi;
 	enum bch_opt_id opt_id;
-	u16 block_size;
 	int ret;
 
 	ret = bch2_sb_compatible(sb, out);
 	if (ret)
 		return ret;
 
-	if (sb->features[1] ||
-	    (le64_to_cpu(sb->features[0]) & (~0ULL << BCH_FEATURE_NR))) {
-		prt_printf(out, "Filesystem has incompatible features");
+	u64 incompat = le64_to_cpu(sb->features[0]) & (~0ULL << BCH_FEATURE_NR);
+	unsigned incompat_bit = 0;
+	if (incompat)
+		incompat_bit = __ffs64(incompat);
+	else if (sb->features[1])
+		incompat_bit = 64 + __ffs64(le64_to_cpu(sb->features[1]));
+
+	if (incompat_bit) {
+		prt_printf(out, "Filesystem has incompatible feature bit %u, highest supported %s (%u)",
+			   incompat_bit,
+			   bch2_sb_features[BCH_FEATURE_NR - 1],
+			   BCH_FEATURE_NR - 1);
 		return -BCH_ERR_invalid_sb_features;
 	}
 
 	if (BCH_VERSION_MAJOR(le16_to_cpu(sb->version)) > BCH_VERSION_MAJOR(bcachefs_metadata_version_current) ||
 	    BCH_SB_VERSION_INCOMPAT(sb) > bcachefs_metadata_version_current) {
-		prt_printf(out, "Filesystem has incompatible version");
+		prt_str(out, "Filesystem has incompatible version ");
+		bch2_version_to_text(out, le16_to_cpu(sb->version));
+		prt_str(out, ", current version ");
+		bch2_version_to_text(out, bcachefs_metadata_version_current);
 		return -BCH_ERR_invalid_sb_features;
 	}
 
-	block_size = le16_to_cpu(sb->block_size);
-
-	if (block_size > PAGE_SECTORS) {
-		prt_printf(out, "Block size too big (got %u, max %u)",
-		       block_size, PAGE_SECTORS);
-		return -BCH_ERR_invalid_sb_block_size;
-	}
-
 	if (bch2_is_zero(sb->user_uuid.b, sizeof(sb->user_uuid))) {
 		prt_printf(out, "Bad user UUID (got zeroes)");
 		return -BCH_ERR_invalid_sb_uuid;
@@ -409,6 +410,13 @@ static int bch2_sb_validate(struct bch_sb_handle *disk_sb,
 		return -BCH_ERR_invalid_sb_uuid;
 	}
 
+	if (!(flags & BCH_VALIDATE_write) &&
+	    le64_to_cpu(sb->offset) != read_offset) {
+		prt_printf(out, "Bad sb offset (got %llu, read from %llu)",
+			   le64_to_cpu(sb->offset), read_offset);
+		return -BCH_ERR_invalid_sb_offset;
+	}
+
 	if (!sb->nr_devices ||
 	    sb->nr_devices > BCH_SB_MEMBERS_MAX) {
 		prt_printf(out, "Bad number of member devices %u (max %u)",
@@ -464,6 +472,13 @@ static int bch2_sb_validate(struct bch_sb_handle *disk_sb,
 
 		if (le16_to_cpu(sb->version) <= bcachefs_metadata_version_disk_accounting_v2)
 			SET_BCH_SB_PROMOTE_WHOLE_EXTENTS(sb, true);
+
+		if (!BCH_SB_WRITE_ERROR_TIMEOUT(sb))
+			SET_BCH_SB_WRITE_ERROR_TIMEOUT(sb, 30);
+
+		if (le16_to_cpu(sb->version) <= bcachefs_metadata_version_extent_flags &&
+		    !BCH_SB_CSUM_ERR_RETRY_NR(sb))
+			SET_BCH_SB_CSUM_ERR_RETRY_NR(sb, 3);
 	}
 
 #ifdef __KERNEL__
@@ -474,8 +489,8 @@ static int bch2_sb_validate(struct bch_sb_handle *disk_sb,
 	for (opt_id = 0; opt_id < bch2_opts_nr; opt_id++) {
 		const struct bch_option *opt = bch2_opt_table + opt_id;
 
-		if (opt->get_sb != BCH2_NO_SB_OPT) {
-			u64 v = bch2_opt_from_sb(sb, opt_id);
+		if (opt->get_sb) {
+			u64 v = bch2_opt_from_sb(sb, opt_id, -1);
 
 			prt_printf(out, "Invalid option ");
 			ret = bch2_opt_validate(opt, v, out);
@@ -755,7 +770,7 @@ static int __bch2_read_super(const char *path, struct bch_opts *opts,
 	memset(sb, 0, sizeof(*sb));
 	sb->mode	= BLK_OPEN_READ;
 	sb->have_bio	= true;
-	sb->holder	= kmalloc(1, GFP_KERNEL);
+	sb->holder	= kzalloc(sizeof(*sb->holder), GFP_KERNEL);
 	if (!sb->holder)
 		return -ENOMEM;
 
@@ -881,7 +896,7 @@ static int __bch2_read_super(const char *path, struct bch_opts *opts,
 
 	sb->have_layout = true;
 
-	ret = bch2_sb_validate(sb, 0, &err);
+	ret = bch2_sb_validate(sb->sb, offset, 0, &err);
 	if (ret) {
 		bch2_print_opts(opts, KERN_ERR "bcachefs (%s): error validating superblock: %s\n",
 				path, err.buf);
@@ -918,16 +933,16 @@ static void write_super_endio(struct bio *bio)
 {
 	struct bch_dev *ca = bio->bi_private;
 
+	bch2_account_io_success_fail(ca, bio_data_dir(bio), !bio->bi_status);
+
 	/* XXX: return errors directly */
 
-	if (bch2_dev_io_err_on(bio->bi_status, ca,
-			       bio_data_dir(bio)
-			       ? BCH_MEMBER_ERROR_write
-			       : BCH_MEMBER_ERROR_read,
-			       "superblock %s error: %s",
+	if (bio->bi_status) {
+		bch_err_dev_ratelimited(ca, "superblock %s error: %s",
 			       str_write_read(bio_data_dir(bio)),
-			       bch2_blk_status_to_str(bio->bi_status)))
+			       bch2_blk_status_to_str(bio->bi_status));
 		ca->sb_write_error = 1;
+	}
 
 	closure_put(&ca->fs->sb_write);
 	percpu_ref_put(&ca->io_ref);
@@ -1038,7 +1053,7 @@ int bch2_write_super(struct bch_fs *c)
 	darray_for_each(online_devices, ca) {
 		printbuf_reset(&err);
 
-		ret = bch2_sb_validate(&(*ca)->disk_sb, BCH_VALIDATE_write, &err);
+		ret = bch2_sb_validate((*ca)->disk_sb.sb, 0, BCH_VALIDATE_write, &err);
 		if (ret) {
 			bch2_fs_inconsistent(c, "sb invalid before write: %s", err.buf);
 			goto out;
@@ -1166,7 +1181,7 @@ int bch2_write_super(struct bch_fs *c)
 				  !can_mount_with_written), c,
 		": Unable to write superblock to sufficient devices (from %ps)",
 		(void *) _RET_IP_))
-		ret = -1;
+		ret = -BCH_ERR_erofs_sb_err;
 out:
 	/* Make new options visible after they're persistent: */
 	bch2_sb_update(c);
@@ -1223,12 +1238,11 @@ void bch2_sb_upgrade(struct bch_fs *c, unsigned new_version, bool incompat)
 		bch2_sb_field_resize(&c->disk_sb, downgrade, 0);
 
 	c->disk_sb.sb->version = cpu_to_le16(new_version);
-	c->disk_sb.sb->features[0] |= cpu_to_le64(BCH_SB_FEATURES_ALL);
 
 	if (incompat) {
+		c->disk_sb.sb->features[0] |= cpu_to_le64(BCH_SB_FEATURES_ALL);
 		SET_BCH_SB_VERSION_INCOMPAT_ALLOWED(c->disk_sb.sb,
 			max(BCH_SB_VERSION_INCOMPAT_ALLOWED(c->disk_sb.sb), new_version));
-		c->disk_sb.sb->features[0] |= cpu_to_le64(BCH_FEATURE_incompat_version_field);
 	}
 }
 
@@ -1459,8 +1473,8 @@ void bch2_sb_to_text(struct printbuf *out, struct bch_sb *sb,
 		for (id = 0; id < bch2_opts_nr; id++) {
 			const struct bch_option *opt = bch2_opt_table + id;
 
-			if (opt->get_sb != BCH2_NO_SB_OPT) {
-				u64 v = bch2_opt_from_sb(sb, id);
+			if (opt->get_sb) {
+				u64 v = bch2_opt_from_sb(sb, id, -1);
 
 				prt_printf(out, "%s:\t", opt->attr.name);
 				bch2_opt_to_text(out, NULL, sb, opt, v,
diff --git a/fs/bcachefs/super-io.h b/fs/bcachefs/super-io.h
index b4cff9ebdebb..78f708a6fbcd 100644
--- a/fs/bcachefs/super-io.h
+++ b/fs/bcachefs/super-io.h
@@ -21,13 +21,13 @@ static inline bool bch2_version_compatible(u16 version)
 void bch2_version_to_text(struct printbuf *, enum bcachefs_metadata_version);
 enum bcachefs_metadata_version bch2_latest_compatible_version(enum bcachefs_metadata_version);
 
-bool bch2_set_version_incompat(struct bch_fs *, enum bcachefs_metadata_version);
+int bch2_set_version_incompat(struct bch_fs *, enum bcachefs_metadata_version);
 
-static inline bool bch2_request_incompat_feature(struct bch_fs *c,
-						 enum bcachefs_metadata_version version)
+static inline int bch2_request_incompat_feature(struct bch_fs *c,
+						enum bcachefs_metadata_version version)
 {
 	return likely(version <= c->sb.version_incompat)
-		? true
+		? 0
 		: bch2_set_version_incompat(c, version);
 }
 
@@ -92,6 +92,8 @@ int bch2_sb_from_fs(struct bch_fs *, struct bch_dev *);
 void bch2_free_super(struct bch_sb_handle *);
 int bch2_sb_realloc(struct bch_sb_handle *, unsigned);
 
+int bch2_sb_validate(struct bch_sb *, u64, enum bch_validate_flags, struct printbuf *);
+
 int bch2_read_super(const char *, struct bch_opts *, struct bch_sb_handle *);
 int bch2_read_super_silent(const char *, struct bch_opts *, struct bch_sb_handle *);
 int bch2_write_super(struct bch_fs *);
diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c
index 0459c875e189..99f9a0aaa380 100644
--- a/fs/bcachefs/super.c
+++ b/fs/bcachefs/super.c
@@ -75,9 +75,6 @@
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Kent Overstreet <kent.overstreet@gmail.com>");
 MODULE_DESCRIPTION("bcachefs filesystem");
-MODULE_SOFTDEP("pre: crc32c");
-MODULE_SOFTDEP("pre: crc64");
-MODULE_SOFTDEP("pre: sha256");
 MODULE_SOFTDEP("pre: chacha20");
 MODULE_SOFTDEP("pre: poly1305");
 MODULE_SOFTDEP("pre: xxhash");
@@ -718,7 +715,7 @@ static int bch2_fs_online(struct bch_fs *c)
 	    kobject_add(&c->time_stats, &c->kobj, "time_stats") ?:
 #endif
 	    kobject_add(&c->counters_kobj, &c->kobj, "counters") ?:
-	    bch2_opts_create_sysfs_files(&c->opts_dir);
+	    bch2_opts_create_sysfs_files(&c->opts_dir, OPT_FS);
 	if (ret) {
 		bch_err(c, "error creating sysfs objects");
 		return ret;
@@ -837,6 +834,25 @@ static struct bch_fs *bch2_fs_alloc(struct bch_sb *sb, struct bch_opts opts)
 	if (ret)
 		goto err;
 
+#ifdef CONFIG_UNICODE
+	/* Default encoding until we can potentially have more as an option. */
+	c->cf_encoding = utf8_load(BCH_FS_DEFAULT_UTF8_ENCODING);
+	if (IS_ERR(c->cf_encoding)) {
+		printk(KERN_ERR "Cannot load UTF-8 encoding for filesystem. Version: %u.%u.%u",
+			unicode_major(BCH_FS_DEFAULT_UTF8_ENCODING),
+			unicode_minor(BCH_FS_DEFAULT_UTF8_ENCODING),
+			unicode_rev(BCH_FS_DEFAULT_UTF8_ENCODING));
+		ret = -EINVAL;
+		goto err;
+	}
+#else
+	if (c->sb.features & BIT_ULL(BCH_FEATURE_casefolding)) {
+		printk(KERN_ERR "Cannot mount a filesystem with casefolding on a kernel without CONFIG_UNICODE\n");
+		ret = -EINVAL;
+		goto err;
+	}
+#endif
+
 	pr_uuid(&name, c->sb.user_uuid.b);
 	ret = name.allocation_failure ? -BCH_ERR_ENOMEM_fs_name_alloc : 0;
 	if (ret)
@@ -1056,6 +1072,7 @@ int bch2_fs_start(struct bch_fs *c)
 	}
 
 	set_bit(BCH_FS_started, &c->flags);
+	wake_up(&c->ro_ref_wait);
 
 	if (c->opts.read_only) {
 		bch2_fs_read_only(c);
@@ -1280,8 +1297,8 @@ static int bch2_dev_sysfs_online(struct bch_fs *c, struct bch_dev *ca)
 		return 0;
 
 	if (!ca->kobj.state_in_sysfs) {
-		ret = kobject_add(&ca->kobj, &c->kobj,
-				  "dev-%u", ca->dev_idx);
+		ret =   kobject_add(&ca->kobj, &c->kobj, "dev-%u", ca->dev_idx) ?:
+			bch2_opts_create_sysfs_files(&ca->kobj, OPT_DEVICE);
 		if (ret)
 			return ret;
 	}
@@ -1412,6 +1429,13 @@ static int __bch2_dev_attach_bdev(struct bch_dev *ca, struct bch_sb_handle *sb)
 	ca->disk_sb = *sb;
 	memset(sb, 0, sizeof(*sb));
 
+	/*
+	 * Stash pointer to the filesystem for blk_holder_ops - note that once
+	 * attached to a filesystem, we will always close the block device
+	 * before tearing down the filesystem object.
+	 */
+	ca->disk_sb.holder->c = ca->fs;
+
 	ca->dev = ca->disk_sb.bdev->bd_dev;
 
 	percpu_ref_reinit(&ca->io_ref);
@@ -1966,15 +1990,12 @@ int bch2_dev_resize(struct bch_fs *c, struct bch_dev *ca, u64 nbuckets)
 	mutex_unlock(&c->sb_lock);
 
 	if (ca->mi.freespace_initialized) {
-		struct disk_accounting_pos acc = {
-			.type = BCH_DISK_ACCOUNTING_dev_data_type,
-			.dev_data_type.dev = ca->dev_idx,
-			.dev_data_type.data_type = BCH_DATA_free,
-		};
 		u64 v[3] = { nbuckets - old_nbuckets, 0, 0 };
 
 		ret   = bch2_trans_commit_do(ca->fs, NULL, NULL, 0,
-				bch2_disk_accounting_mod(trans, &acc, v, ARRAY_SIZE(v), false)) ?:
+				bch2_disk_accounting_mod2(trans, false, v, dev_data_type,
+							  .dev = ca->dev_idx,
+							  .data_type = BCH_DATA_free)) ?:
 			bch2_dev_freespace_init(c, ca, old_nbuckets, nbuckets);
 		if (ret)
 			goto err;
@@ -1998,6 +2019,102 @@ struct bch_dev *bch2_dev_lookup(struct bch_fs *c, const char *name)
 	return ERR_PTR(-BCH_ERR_ENOENT_dev_not_found);
 }
 
+/* blk_holder_ops: */
+
+static struct bch_fs *bdev_get_fs(struct block_device *bdev)
+	__releases(&bdev->bd_holder_lock)
+{
+	struct bch_sb_handle_holder *holder = bdev->bd_holder;
+	struct bch_fs *c = holder->c;
+
+	if (c && !bch2_ro_ref_tryget(c))
+		c = NULL;
+
+	mutex_unlock(&bdev->bd_holder_lock);
+
+	if (c)
+		wait_event(c->ro_ref_wait, test_bit(BCH_FS_started, &c->flags));
+	return c;
+}
+
+/* returns with ref on ca->ref */
+static struct bch_dev *bdev_to_bch_dev(struct bch_fs *c, struct block_device *bdev)
+{
+	for_each_member_device(c, ca)
+		if (ca->disk_sb.bdev == bdev)
+			return ca;
+	return NULL;
+}
+
+static void bch2_fs_bdev_mark_dead(struct block_device *bdev, bool surprise)
+{
+	struct bch_fs *c = bdev_get_fs(bdev);
+	if (!c)
+		return;
+
+	struct super_block *sb = c->vfs_sb;
+	if (sb) {
+		/*
+		 * Not necessary, c->ro_ref guards against the filesystem being
+		 * unmounted - we only take this to avoid a warning in
+		 * sync_filesystem:
+		 */
+		down_read(&sb->s_umount);
+	}
+
+	down_write(&c->state_lock);
+	struct bch_dev *ca = bdev_to_bch_dev(c, bdev);
+	if (!ca)
+		goto unlock;
+
+	if (bch2_dev_state_allowed(c, ca, BCH_MEMBER_STATE_failed, BCH_FORCE_IF_DEGRADED)) {
+		__bch2_dev_offline(c, ca);
+	} else {
+		if (sb) {
+			if (!surprise)
+				sync_filesystem(sb);
+			shrink_dcache_sb(sb);
+			evict_inodes(sb);
+		}
+
+		bch2_journal_flush(&c->journal);
+		bch2_fs_emergency_read_only(c);
+	}
+
+	bch2_dev_put(ca);
+unlock:
+	if (sb)
+		up_read(&sb->s_umount);
+	up_write(&c->state_lock);
+	bch2_ro_ref_put(c);
+}
+
+static void bch2_fs_bdev_sync(struct block_device *bdev)
+{
+	struct bch_fs *c = bdev_get_fs(bdev);
+	if (!c)
+		return;
+
+	struct super_block *sb = c->vfs_sb;
+	if (sb) {
+		/*
+		 * Not necessary, c->ro_ref guards against the filesystem being
+		 * unmounted - we only take this to avoid a warning in
+		 * sync_filesystem:
+		 */
+		down_read(&sb->s_umount);
+		sync_filesystem(sb);
+		up_read(&sb->s_umount);
+	}
+
+	bch2_ro_ref_put(c);
+}
+
+const struct blk_holder_ops bch2_sb_handle_bdev_ops = {
+	.mark_dead		= bch2_fs_bdev_mark_dead,
+	.sync			= bch2_fs_bdev_sync,
+};
+
 /* Filesystem open: */
 
 static inline int sb_cmp(struct bch_sb *l, struct bch_sb *r)
diff --git a/fs/bcachefs/super.h b/fs/bcachefs/super.h
index 04f8287eff5c..23533bce5709 100644
--- a/fs/bcachefs/super.h
+++ b/fs/bcachefs/super.h
@@ -42,4 +42,6 @@ void bch2_fs_stop(struct bch_fs *);
 int bch2_fs_start(struct bch_fs *);
 struct bch_fs *bch2_fs_open(char * const *, unsigned, struct bch_opts);
 
+extern const struct blk_holder_ops bch2_sb_handle_bdev_ops;
+
 #endif /* _BCACHEFS_SUPER_H */
diff --git a/fs/bcachefs/super_types.h b/fs/bcachefs/super_types.h
index 368a63d938cf..3a899f799d1d 100644
--- a/fs/bcachefs/super_types.h
+++ b/fs/bcachefs/super_types.h
@@ -2,13 +2,19 @@
 #ifndef _BCACHEFS_SUPER_TYPES_H
 #define _BCACHEFS_SUPER_TYPES_H
 
+struct bch_fs;
+
+struct bch_sb_handle_holder {
+	struct bch_fs		*c;
+};
+
 struct bch_sb_handle {
 	struct bch_sb		*sb;
 	struct file		*s_bdev_file;
 	struct block_device	*bdev;
 	char			*sb_name;
 	struct bio		*bio;
-	void			*holder;
+	struct bch_sb_handle_holder *holder;
 	size_t			buffer_size;
 	blk_mode_t		mode;
 	unsigned		have_layout:1;
diff --git a/fs/bcachefs/sysfs.c b/fs/bcachefs/sysfs.c
index a7eb1f511484..8c200b558c69 100644
--- a/fs/bcachefs/sysfs.c
+++ b/fs/bcachefs/sysfs.c
@@ -146,15 +146,15 @@ write_attribute(trigger_journal_writes);
 write_attribute(trigger_btree_cache_shrink);
 write_attribute(trigger_btree_key_cache_shrink);
 write_attribute(trigger_freelist_wakeup);
+write_attribute(trigger_btree_updates);
 read_attribute(gc_gens_pos);
+__sysfs_attribute(read_fua_test, 0400);
 
 read_attribute(uuid);
 read_attribute(minor);
 read_attribute(flags);
-read_attribute(bucket_size);
 read_attribute(first_bucket);
 read_attribute(nbuckets);
-rw_attribute(durability);
 read_attribute(io_done);
 read_attribute(io_errors);
 write_attribute(io_errors_reset);
@@ -173,10 +173,8 @@ read_attribute(journal_debug);
 read_attribute(btree_cache);
 read_attribute(btree_key_cache);
 read_attribute(btree_reserve_cache);
-read_attribute(stripes_heap);
 read_attribute(open_buckets);
 read_attribute(open_buckets_partial);
-read_attribute(write_points);
 read_attribute(nocow_lock_table);
 
 #ifdef BCH_WRITE_REF_DEBUG
@@ -209,8 +207,6 @@ read_attribute(usage_base);
 BCH_PERSISTENT_COUNTERS()
 #undef x
 
-rw_attribute(discard);
-read_attribute(state);
 rw_attribute(label);
 
 read_attribute(copy_gc_wait);
@@ -315,6 +311,116 @@ static void bch2_fs_usage_base_to_text(struct printbuf *out, struct bch_fs *c)
 	prt_printf(out, "nr_inodes:\t%llu\n",	b.nr_inodes);
 }
 
+static int bch2_read_fua_test(struct printbuf *out, struct bch_dev *ca)
+{
+	struct bch_fs *c = ca->fs;
+	struct bio *bio = NULL;
+	void *buf = NULL;
+	unsigned bs = c->opts.block_size, iters;
+	u64 end, test_duration = NSEC_PER_SEC * 2;
+	struct bch2_time_stats stats_nofua, stats_fua, stats_random;
+	int ret = 0;
+
+	bch2_time_stats_init_no_pcpu(&stats_nofua);
+	bch2_time_stats_init_no_pcpu(&stats_fua);
+	bch2_time_stats_init_no_pcpu(&stats_random);
+
+	if (!bch2_dev_get_ioref(c, ca->dev_idx, READ)) {
+		prt_str(out, "offline\n");
+		return 0;
+	}
+
+	struct block_device *bdev = ca->disk_sb.bdev;
+
+	bio = bio_kmalloc(1, GFP_KERNEL);
+	if (!bio) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	buf = kmalloc(bs, GFP_KERNEL);
+	if (!buf)
+		goto err;
+
+	end = ktime_get_ns() + test_duration;
+	for (iters = 0; iters < 1000 && time_before64(ktime_get_ns(), end); iters++) {
+		bio_init(bio, bdev, bio->bi_inline_vecs, 1, READ);
+		bch2_bio_map(bio, buf, bs);
+
+		u64 submit_time = ktime_get_ns();
+		ret = submit_bio_wait(bio);
+		bch2_time_stats_update(&stats_nofua, submit_time);
+
+		if (ret)
+			goto err;
+	}
+
+	end = ktime_get_ns() + test_duration;
+	for (iters = 0; iters < 1000 && time_before64(ktime_get_ns(), end); iters++) {
+		bio_init(bio, bdev, bio->bi_inline_vecs, 1, REQ_FUA|READ);
+		bch2_bio_map(bio, buf, bs);
+
+		u64 submit_time = ktime_get_ns();
+		ret = submit_bio_wait(bio);
+		bch2_time_stats_update(&stats_fua, submit_time);
+
+		if (ret)
+			goto err;
+	}
+
+	u64 dev_size = ca->mi.nbuckets * bucket_bytes(ca);
+
+	end = ktime_get_ns() + test_duration;
+	for (iters = 0; iters < 1000 && time_before64(ktime_get_ns(), end); iters++) {
+		bio_init(bio, bdev, bio->bi_inline_vecs, 1, READ);
+		bio->bi_iter.bi_sector = (bch2_get_random_u64_below(dev_size) & ~((u64) bs - 1)) >> 9;
+		bch2_bio_map(bio, buf, bs);
+
+		u64 submit_time = ktime_get_ns();
+		ret = submit_bio_wait(bio);
+		bch2_time_stats_update(&stats_random, submit_time);
+
+		if (ret)
+			goto err;
+	}
+
+	u64 ns_nofua		= mean_and_variance_get_mean(stats_nofua.duration_stats);
+	u64 ns_fua		= mean_and_variance_get_mean(stats_fua.duration_stats);
+	u64 ns_rand		= mean_and_variance_get_mean(stats_random.duration_stats);
+
+	u64 stddev_nofua	= mean_and_variance_get_stddev(stats_nofua.duration_stats);
+	u64 stddev_fua		= mean_and_variance_get_stddev(stats_fua.duration_stats);
+	u64 stddev_rand		= mean_and_variance_get_stddev(stats_random.duration_stats);
+
+	printbuf_tabstop_push(out, 8);
+	printbuf_tabstop_push(out, 12);
+	printbuf_tabstop_push(out, 12);
+	prt_printf(out, "This test must be run on an idle drive for accurate results\n");
+	prt_printf(out, "%s\n", dev_name(&ca->disk_sb.bdev->bd_device));
+	prt_printf(out, "fua support advertized: %s\n", bdev_fua(bdev) ? "yes" : "no");
+	prt_newline(out);
+	prt_printf(out, "ns:\tlatency\rstddev\r\n");
+	prt_printf(out, "nofua\t%llu\r%llu\r\n",	ns_nofua,	stddev_nofua);
+	prt_printf(out, "fua\t%llu\r%llu\r\n",		ns_fua,		stddev_fua);
+	prt_printf(out, "random\t%llu\r%llu\r\n",	ns_rand,	stddev_rand);
+
+	bool read_cache = ns_nofua * 2 < ns_rand;
+	bool fua_cached	= read_cache && ns_fua < (ns_nofua + ns_rand) / 2;
+
+	if (!read_cache)
+		prt_str(out, "reads don't appear to be cached - safe\n");
+	else if (!fua_cached)
+		prt_str(out, "fua reads don't appear to be cached - safe\n");
+	else
+		prt_str(out, "fua reads appear to be cached - unsafe\n");
+err:
+	kfree(buf);
+	kfree(bio);
+	percpu_ref_put(&ca->io_ref);
+	bch_err_fn(c, ret);
+	return ret;
+}
+
 SHOW(bch2_fs)
 {
 	struct bch_fs *c = container_of(kobj, struct bch_fs, kobj);
@@ -355,18 +461,12 @@ SHOW(bch2_fs)
 	if (attr == &sysfs_btree_reserve_cache)
 		bch2_btree_reserve_cache_to_text(out, c);
 
-	if (attr == &sysfs_stripes_heap)
-		bch2_stripes_heap_to_text(out, c);
-
 	if (attr == &sysfs_open_buckets)
 		bch2_open_buckets_to_text(out, c, NULL);
 
 	if (attr == &sysfs_open_buckets_partial)
 		bch2_open_buckets_partial_to_text(out, c);
 
-	if (attr == &sysfs_write_points)
-		bch2_write_points_to_text(out, c);
-
 	if (attr == &sysfs_compression_stats)
 		bch2_compression_stats_to_text(out, c);
 
@@ -415,6 +515,9 @@ STORE(bch2_fs)
 
 	/* Debugging: */
 
+	if (attr == &sysfs_trigger_btree_updates)
+		queue_work(c->btree_interior_update_worker, &c->btree_interior_update_work);
+
 	if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_sysfs))
 		return -EROFS;
 
@@ -566,10 +669,8 @@ struct attribute *bch2_fs_internal_files[] = {
 	&sysfs_btree_key_cache,
 	&sysfs_btree_reserve_cache,
 	&sysfs_new_stripes,
-	&sysfs_stripes_heap,
 	&sysfs_open_buckets,
 	&sysfs_open_buckets_partial,
-	&sysfs_write_points,
 #ifdef BCH_WRITE_REF_DEBUG
 	&sysfs_write_refs,
 #endif
@@ -585,6 +686,7 @@ struct attribute *bch2_fs_internal_files[] = {
 	&sysfs_trigger_btree_cache_shrink,
 	&sysfs_trigger_btree_key_cache_shrink,
 	&sysfs_trigger_freelist_wakeup,
+	&sysfs_trigger_btree_updates,
 
 	&sysfs_gc_gens_pos,
 
@@ -604,26 +706,34 @@ struct attribute *bch2_fs_internal_files[] = {
 
 /* options */
 
-SHOW(bch2_fs_opts_dir)
+static ssize_t sysfs_opt_show(struct bch_fs *c,
+			      struct bch_dev *ca,
+			      enum bch_opt_id id,
+			      struct printbuf *out)
 {
-	struct bch_fs *c = container_of(kobj, struct bch_fs, opts_dir);
-	const struct bch_option *opt = container_of(attr, struct bch_option, attr);
-	int id = opt - bch2_opt_table;
-	u64 v = bch2_opt_get_by_id(&c->opts, id);
+	const struct bch_option *opt = bch2_opt_table + id;
+	u64 v;
+
+	if (opt->flags & OPT_FS) {
+		v = bch2_opt_get_by_id(&c->opts, id);
+	} else if ((opt->flags & OPT_DEVICE) && opt->get_member)  {
+		v = bch2_opt_from_sb(c->disk_sb.sb, id, ca->dev_idx);
+	} else {
+		return -EINVAL;
+	}
 
 	bch2_opt_to_text(out, c, c->disk_sb.sb, opt, v, OPT_SHOW_FULL_LIST);
 	prt_char(out, '\n');
-
 	return 0;
 }
 
-STORE(bch2_fs_opts_dir)
+static ssize_t sysfs_opt_store(struct bch_fs *c,
+			       struct bch_dev *ca,
+			       enum bch_opt_id id,
+			       const char *buf, size_t size)
 {
-	struct bch_fs *c = container_of(kobj, struct bch_fs, opts_dir);
-	const struct bch_option *opt = container_of(attr, struct bch_option, attr);
-	int ret, id = opt - bch2_opt_table;
-	char *tmp;
-	u64 v;
+	const struct bch_option *opt = bch2_opt_table + id;
+	int ret = 0;
 
 	/*
 	 * We don't need to take c->writes for correctness, but it eliminates an
@@ -632,27 +742,28 @@ STORE(bch2_fs_opts_dir)
 	if (unlikely(!bch2_write_ref_tryget(c, BCH_WRITE_REF_sysfs)))
 		return -EROFS;
 
-	tmp = kstrdup(buf, GFP_KERNEL);
+	down_write(&c->state_lock);
+
+	char *tmp = kstrdup(buf, GFP_KERNEL);
 	if (!tmp) {
 		ret = -ENOMEM;
 		goto err;
 	}
 
-	ret = bch2_opt_parse(c, opt, strim(tmp), &v, NULL);
+	u64 v;
+	ret =   bch2_opt_parse(c, opt, strim(tmp), &v, NULL) ?:
+		bch2_opt_check_may_set(c, ca, id, v);
 	kfree(tmp);
 
 	if (ret < 0)
 		goto err;
 
-	ret = bch2_opt_check_may_set(c, id, v);
-	if (ret < 0)
-		goto err;
-
-	bch2_opt_set_sb(c, NULL, opt, v);
+	bch2_opt_set_sb(c, ca, opt, v);
 	bch2_opt_set_by_id(&c->opts, id, v);
 
 	if (v &&
 	    (id == Opt_background_target ||
+	     (id == Opt_foreground_target && !c->opts.background_target) ||
 	     id == Opt_background_compression ||
 	     (id == Opt_compression && !c->opts.background_compression)))
 		bch2_set_rebalance_needs_scan(c, 0);
@@ -664,27 +775,56 @@ STORE(bch2_fs_opts_dir)
 	    c->copygc_thread)
 		wake_up_process(c->copygc_thread);
 
+	if (id == Opt_discard && !ca) {
+		mutex_lock(&c->sb_lock);
+		for_each_member_device(c, ca)
+			opt->set_member(bch2_members_v2_get_mut(ca->disk_sb.sb, ca->dev_idx), v);
+
+		bch2_write_super(c);
+		mutex_unlock(&c->sb_lock);
+	}
+
 	ret = size;
 err:
+	up_write(&c->state_lock);
 	bch2_write_ref_put(c, BCH_WRITE_REF_sysfs);
 	return ret;
 }
+
+SHOW(bch2_fs_opts_dir)
+{
+	struct bch_fs *c = container_of(kobj, struct bch_fs, opts_dir);
+	int id = bch2_opt_lookup(attr->name);
+	if (id < 0)
+		return 0;
+
+	return sysfs_opt_show(c, NULL, id, out);
+}
+
+STORE(bch2_fs_opts_dir)
+{
+	struct bch_fs *c = container_of(kobj, struct bch_fs, opts_dir);
+	int id = bch2_opt_lookup(attr->name);
+	if (id < 0)
+		return 0;
+
+	return sysfs_opt_store(c, NULL, id, buf, size);
+}
 SYSFS_OPS(bch2_fs_opts_dir);
 
 struct attribute *bch2_fs_opts_dir_files[] = { NULL };
 
-int bch2_opts_create_sysfs_files(struct kobject *kobj)
+int bch2_opts_create_sysfs_files(struct kobject *kobj, unsigned type)
 {
-	const struct bch_option *i;
-	int ret;
-
-	for (i = bch2_opt_table;
+	for (const struct bch_option *i = bch2_opt_table;
 	     i < bch2_opt_table + bch2_opts_nr;
 	     i++) {
-		if (!(i->flags & OPT_FS))
+		if (i->flags & OPT_HIDDEN)
+			continue;
+		if (!(i->flags & type))
 			continue;
 
-		ret = sysfs_create_file(kobj, &i->attr);
+		int ret = sysfs_create_file(kobj, &i->attr);
 		if (ret)
 			return ret;
 	}
@@ -755,11 +895,8 @@ SHOW(bch2_dev)
 
 	sysfs_printf(uuid,		"%pU\n", ca->uuid.b);
 
-	sysfs_print(bucket_size,	bucket_bytes(ca));
 	sysfs_print(first_bucket,	ca->mi.first_bucket);
 	sysfs_print(nbuckets,		ca->mi.nbuckets);
-	sysfs_print(durability,		ca->mi.durability);
-	sysfs_print(discard,		ca->mi.discard);
 
 	if (attr == &sysfs_label) {
 		if (ca->mi.group)
@@ -772,11 +909,6 @@ SHOW(bch2_dev)
 		prt_char(out, '\n');
 	}
 
-	if (attr == &sysfs_state) {
-		prt_string_option(out, bch2_member_states, ca->mi.state);
-		prt_char(out, '\n');
-	}
-
 	if (attr == &sysfs_io_done)
 		dev_io_done_to_text(out, ca);
 
@@ -802,6 +934,13 @@ SHOW(bch2_dev)
 	if (attr == &sysfs_open_buckets)
 		bch2_open_buckets_to_text(out, c, ca);
 
+	if (attr == &sysfs_read_fua_test)
+		return bch2_read_fua_test(out, ca);
+
+	int opt_id = bch2_opt_lookup(attr->name);
+	if (opt_id >= 0)
+		return sysfs_opt_show(c, ca, opt_id, out);
+
 	return 0;
 }
 
@@ -810,18 +949,6 @@ STORE(bch2_dev)
 	struct bch_dev *ca = container_of(kobj, struct bch_dev, kobj);
 	struct bch_fs *c = ca->fs;
 
-	if (attr == &sysfs_discard) {
-		bool v = strtoul_or_return(buf);
-
-		bch2_opt_set_sb(c, ca, bch2_opt_table + Opt_discard, v);
-	}
-
-	if (attr == &sysfs_durability) {
-		u64 v = strtoul_or_return(buf);
-
-		bch2_opt_set_sb(c, ca, bch2_opt_table + Opt_durability, v);
-	}
-
 	if (attr == &sysfs_label) {
 		char *tmp;
 		int ret;
@@ -839,20 +966,20 @@ STORE(bch2_dev)
 	if (attr == &sysfs_io_errors_reset)
 		bch2_dev_errors_reset(ca);
 
+	int opt_id = bch2_opt_lookup(attr->name);
+	if (opt_id >= 0)
+		return sysfs_opt_store(c, ca, opt_id, buf, size);
+
 	return size;
 }
 SYSFS_OPS(bch2_dev);
 
 struct attribute *bch2_dev_files[] = {
 	&sysfs_uuid,
-	&sysfs_bucket_size,
 	&sysfs_first_bucket,
 	&sysfs_nbuckets,
-	&sysfs_durability,
 
 	/* settings: */
-	&sysfs_discard,
-	&sysfs_state,
 	&sysfs_label,
 
 	&sysfs_has_data,
@@ -866,6 +993,8 @@ struct attribute *bch2_dev_files[] = {
 	&sysfs_io_latency_stats_write,
 	&sysfs_congested,
 
+	&sysfs_read_fua_test,
+
 	/* debug: */
 	&sysfs_alloc_debug,
 	&sysfs_open_buckets,
diff --git a/fs/bcachefs/sysfs.h b/fs/bcachefs/sysfs.h
index 222cd5062702..303e0433c702 100644
--- a/fs/bcachefs/sysfs.h
+++ b/fs/bcachefs/sysfs.h
@@ -23,7 +23,7 @@ extern const struct sysfs_ops bch2_fs_opts_dir_sysfs_ops;
 extern const struct sysfs_ops bch2_fs_time_stats_sysfs_ops;
 extern const struct sysfs_ops bch2_dev_sysfs_ops;
 
-int bch2_opts_create_sysfs_files(struct kobject *);
+int bch2_opts_create_sysfs_files(struct kobject *, unsigned);
 
 #else
 
@@ -41,7 +41,8 @@ static const struct sysfs_ops bch2_fs_opts_dir_sysfs_ops;
 static const struct sysfs_ops bch2_fs_time_stats_sysfs_ops;
 static const struct sysfs_ops bch2_dev_sysfs_ops;
 
-static inline int bch2_opts_create_sysfs_files(struct kobject *kobj) { return 0; }
+static inline int bch2_opts_create_sysfs_files(struct kobject *kobj, unsigned type)
+{ return 0; }
 
 #endif /* NO_BCACHEFS_SYSFS */
 
diff --git a/fs/bcachefs/time_stats.c b/fs/bcachefs/time_stats.c
index 3fe82757f93a..a8382d876835 100644
--- a/fs/bcachefs/time_stats.c
+++ b/fs/bcachefs/time_stats.c
@@ -10,6 +10,9 @@
 #include "eytzinger.h"
 #include "time_stats.h"
 
+/* disable automatic switching to percpu mode */
+#define TIME_STATS_NONPCPU	((struct time_stat_buffer *) 1)
+
 static const struct time_unit time_units[] = {
 	{ "ns",		1		 },
 	{ "us",		NSEC_PER_USEC	 },
@@ -123,11 +126,12 @@ void __bch2_time_stats_update(struct bch2_time_stats *stats, u64 start, u64 end)
 {
 	unsigned long flags;
 
-	if (!stats->buffer) {
+	if ((unsigned long) stats->buffer <= 1) {
 		spin_lock_irqsave(&stats->lock, flags);
 		time_stats_update_one(stats, start, end);
 
-		if (mean_and_variance_weighted_get_mean(stats->freq_stats_weighted, TIME_STATS_MV_WEIGHT) < 32 &&
+		if (!stats->buffer &&
+		    mean_and_variance_weighted_get_mean(stats->freq_stats_weighted, TIME_STATS_MV_WEIGHT) < 32 &&
 		    stats->duration_stats.n > 1024)
 			stats->buffer =
 				alloc_percpu_gfp(struct time_stat_buffer,
@@ -157,7 +161,8 @@ void bch2_time_stats_reset(struct bch2_time_stats *stats)
 	unsigned offset = offsetof(struct bch2_time_stats, min_duration);
 	memset((void *) stats + offset, 0, sizeof(*stats) - offset);
 
-	if (stats->buffer) {
+	if (stats->buffer &&
+	    stats->buffer != TIME_STATS_NONPCPU) {
 		int cpu;
 		for_each_possible_cpu(cpu)
 			per_cpu_ptr(stats->buffer, cpu)->nr = 0;
@@ -167,7 +172,10 @@ void bch2_time_stats_reset(struct bch2_time_stats *stats)
 
 void bch2_time_stats_exit(struct bch2_time_stats *stats)
 {
-	free_percpu(stats->buffer);
+	if (stats->buffer != TIME_STATS_NONPCPU) {
+		free_percpu(stats->buffer);
+		stats->buffer = NULL;
+	}
 }
 
 void bch2_time_stats_init(struct bch2_time_stats *stats)
@@ -177,3 +185,9 @@ void bch2_time_stats_init(struct bch2_time_stats *stats)
 	stats->min_freq = U64_MAX;
 	spin_lock_init(&stats->lock);
 }
+
+void bch2_time_stats_init_no_pcpu(struct bch2_time_stats *stats)
+{
+	bch2_time_stats_init(stats);
+	stats->buffer = TIME_STATS_NONPCPU;
+}
diff --git a/fs/bcachefs/time_stats.h b/fs/bcachefs/time_stats.h
index dc6493f7bbab..eddb0985bab4 100644
--- a/fs/bcachefs/time_stats.h
+++ b/fs/bcachefs/time_stats.h
@@ -145,6 +145,7 @@ static inline bool track_event_change(struct bch2_time_stats *stats, bool v)
 void bch2_time_stats_reset(struct bch2_time_stats *);
 void bch2_time_stats_exit(struct bch2_time_stats *);
 void bch2_time_stats_init(struct bch2_time_stats *);
+void bch2_time_stats_init_no_pcpu(struct bch2_time_stats *);
 
 static inline void bch2_time_stats_quantiles_exit(struct bch2_time_stats_quantiles *statq)
 {
diff --git a/fs/bcachefs/trace.h b/fs/bcachefs/trace.h
index c1b51009edf6..8c07189a080a 100644
--- a/fs/bcachefs/trace.h
+++ b/fs/bcachefs/trace.h
@@ -295,12 +295,12 @@ TRACE_EVENT(write_super,
 
 /* io.c: */
 
-DEFINE_EVENT(bio, read_promote,
+DEFINE_EVENT(bio, io_read_promote,
 	TP_PROTO(struct bio *bio),
 	TP_ARGS(bio)
 );
 
-TRACE_EVENT(read_nopromote,
+TRACE_EVENT(io_read_nopromote,
 	TP_PROTO(struct bch_fs *c, int ret),
 	TP_ARGS(c, ret),
 
@@ -319,26 +319,55 @@ TRACE_EVENT(read_nopromote,
 		  __entry->ret)
 );
 
-DEFINE_EVENT(bio, read_bounce,
+DEFINE_EVENT(bio, io_read_bounce,
 	TP_PROTO(struct bio *bio),
 	TP_ARGS(bio)
 );
 
-DEFINE_EVENT(bio, read_split,
+DEFINE_EVENT(bio, io_read_split,
 	TP_PROTO(struct bio *bio),
 	TP_ARGS(bio)
 );
 
-DEFINE_EVENT(bio, read_retry,
+DEFINE_EVENT(bio, io_read_retry,
 	TP_PROTO(struct bio *bio),
 	TP_ARGS(bio)
 );
 
-DEFINE_EVENT(bio, read_reuse_race,
+DEFINE_EVENT(bio, io_read_reuse_race,
 	TP_PROTO(struct bio *bio),
 	TP_ARGS(bio)
 );
 
+DEFINE_EVENT(bio, io_read_fail_and_poison,
+	TP_PROTO(struct bio *bio),
+	TP_ARGS(bio)
+);
+
+/* ec.c */
+
+TRACE_EVENT(stripe_create,
+	TP_PROTO(struct bch_fs *c, u64 idx, int ret),
+	TP_ARGS(c, idx, ret),
+
+	TP_STRUCT__entry(
+		__field(dev_t,		dev			)
+		__field(u64,		idx			)
+		__field(int,		ret			)
+	),
+
+	TP_fast_assign(
+		__entry->dev			= c->dev;
+		__entry->idx			= idx;
+		__entry->ret			= ret;
+	),
+
+	TP_printk("%d,%d idx %llu ret %i",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->idx,
+		  __entry->ret)
+);
+
 /* Journal */
 
 DEFINE_EVENT(bch_fs, journal_full,
@@ -797,53 +826,37 @@ TRACE_EVENT(bucket_invalidate,
 
 /* Moving IO */
 
-TRACE_EVENT(bucket_evacuate,
-	TP_PROTO(struct bch_fs *c, struct bpos *bucket),
-	TP_ARGS(c, bucket),
-
-	TP_STRUCT__entry(
-		__field(dev_t,		dev			)
-		__field(u32,		dev_idx			)
-		__field(u64,		bucket			)
-	),
-
-	TP_fast_assign(
-		__entry->dev		= c->dev;
-		__entry->dev_idx	= bucket->inode;
-		__entry->bucket		= bucket->offset;
-	),
-
-	TP_printk("%d:%d %u:%llu",
-		  MAJOR(__entry->dev), MINOR(__entry->dev),
-		  __entry->dev_idx, __entry->bucket)
+DEFINE_EVENT(fs_str, io_move,
+	TP_PROTO(struct bch_fs *c, const char *str),
+	TP_ARGS(c, str)
 );
 
-DEFINE_EVENT(fs_str, move_extent,
+DEFINE_EVENT(fs_str, io_move_read,
 	TP_PROTO(struct bch_fs *c, const char *str),
 	TP_ARGS(c, str)
 );
 
-DEFINE_EVENT(fs_str, move_extent_read,
+DEFINE_EVENT(fs_str, io_move_write,
 	TP_PROTO(struct bch_fs *c, const char *str),
 	TP_ARGS(c, str)
 );
 
-DEFINE_EVENT(fs_str, move_extent_write,
+DEFINE_EVENT(fs_str, io_move_finish,
 	TP_PROTO(struct bch_fs *c, const char *str),
 	TP_ARGS(c, str)
 );
 
-DEFINE_EVENT(fs_str, move_extent_finish,
+DEFINE_EVENT(fs_str, io_move_fail,
 	TP_PROTO(struct bch_fs *c, const char *str),
 	TP_ARGS(c, str)
 );
 
-DEFINE_EVENT(fs_str, move_extent_fail,
+DEFINE_EVENT(fs_str, io_move_write_fail,
 	TP_PROTO(struct bch_fs *c, const char *str),
 	TP_ARGS(c, str)
 );
 
-DEFINE_EVENT(fs_str, move_extent_start_fail,
+DEFINE_EVENT(fs_str, io_move_start_fail,
 	TP_PROTO(struct bch_fs *c, const char *str),
 	TP_ARGS(c, str)
 );
@@ -881,37 +894,6 @@ TRACE_EVENT(move_data,
 		  __entry->sectors_raced)
 );
 
-TRACE_EVENT(evacuate_bucket,
-	TP_PROTO(struct bch_fs *c, struct bpos *bucket,
-		 unsigned sectors, unsigned bucket_size,
-		 int ret),
-	TP_ARGS(c, bucket, sectors, bucket_size, ret),
-
-	TP_STRUCT__entry(
-		__field(dev_t,		dev		)
-		__field(u64,		member		)
-		__field(u64,		bucket		)
-		__field(u32,		sectors		)
-		__field(u32,		bucket_size	)
-		__field(int,		ret		)
-	),
-
-	TP_fast_assign(
-		__entry->dev			= c->dev;
-		__entry->member			= bucket->inode;
-		__entry->bucket			= bucket->offset;
-		__entry->sectors		= sectors;
-		__entry->bucket_size		= bucket_size;
-		__entry->ret			= ret;
-	),
-
-	TP_printk("%d,%d %llu:%llu sectors %u/%u ret %i",
-		  MAJOR(__entry->dev), MINOR(__entry->dev),
-		  __entry->member, __entry->bucket,
-		  __entry->sectors, __entry->bucket_size,
-		  __entry->ret)
-);
-
 TRACE_EVENT(copygc,
 	TP_PROTO(struct bch_fs *c,
 		 u64 buckets,
diff --git a/fs/bcachefs/util.c b/fs/bcachefs/util.c
index da2cd11b3025..553de8d8e3e5 100644
--- a/fs/bcachefs/util.c
+++ b/fs/bcachefs/util.c
@@ -473,10 +473,10 @@ void bch2_time_stats_to_text(struct printbuf *out, struct bch2_time_stats *stats
 		u64 last_q = 0;
 
 		prt_printf(out, "quantiles (%s):\t", u->name);
-		eytzinger0_for_each(i, NR_QUANTILES) {
-			bool is_last = eytzinger0_next(i, NR_QUANTILES) == -1;
+		eytzinger0_for_each(j, NR_QUANTILES) {
+			bool is_last = eytzinger0_next(j, NR_QUANTILES) == -1;
 
-			u64 q = max(quantiles->entries[i].m, last_q);
+			u64 q = max(quantiles->entries[j].m, last_q);
 			prt_printf(out, "%llu ", div64_u64(q, u->nsecs));
 			if (is_last)
 				prt_newline(out);
@@ -704,12 +704,33 @@ void memcpy_from_bio(void *dst, struct bio *src, struct bvec_iter src_iter)
 	}
 }
 
+#ifdef CONFIG_BCACHEFS_DEBUG
+void bch2_corrupt_bio(struct bio *bio)
+{
+	struct bvec_iter iter;
+	struct bio_vec bv;
+	unsigned offset = get_random_u32_below(bio->bi_iter.bi_size / sizeof(u64));
+
+	bio_for_each_segment(bv, bio, iter) {
+		unsigned u64s = bv.bv_len / sizeof(u64);
+
+		if (offset < u64s) {
+			u64 *segment = bvec_kmap_local(&bv);
+			segment[offset] = get_random_u64();
+			kunmap_local(segment);
+			return;
+		}
+		offset -= u64s;
+	}
+}
+#endif
+
 #if 0
 void eytzinger1_test(void)
 {
-	unsigned inorder, eytz, size;
+	unsigned inorder, size;
 
-	pr_info("1 based eytzinger test:");
+	pr_info("1 based eytzinger test:\n");
 
 	for (size = 2;
 	     size < 65536;
@@ -717,13 +738,7 @@ void eytzinger1_test(void)
 		unsigned extra = eytzinger1_extra(size);
 
 		if (!(size % 4096))
-			pr_info("tree size %u", size);
-
-		BUG_ON(eytzinger1_prev(0, size) != eytzinger1_last(size));
-		BUG_ON(eytzinger1_next(0, size) != eytzinger1_first(size));
-
-		BUG_ON(eytzinger1_prev(eytzinger1_first(size), size)	!= 0);
-		BUG_ON(eytzinger1_next(eytzinger1_last(size), size)	!= 0);
+			pr_info("tree size %u\n", size);
 
 		inorder = 1;
 		eytzinger1_for_each(eytz, size) {
@@ -734,15 +749,16 @@ void eytzinger1_test(void)
 
 			inorder++;
 		}
+		BUG_ON(inorder - 1 != size);
 	}
 }
 
 void eytzinger0_test(void)
 {
 
-	unsigned inorder, eytz, size;
+	unsigned inorder, size;
 
-	pr_info("0 based eytzinger test:");
+	pr_info("0 based eytzinger test:\n");
 
 	for (size = 1;
 	     size < 65536;
@@ -750,13 +766,7 @@ void eytzinger0_test(void)
 		unsigned extra = eytzinger0_extra(size);
 
 		if (!(size % 4096))
-			pr_info("tree size %u", size);
-
-		BUG_ON(eytzinger0_prev(-1, size) != eytzinger0_last(size));
-		BUG_ON(eytzinger0_next(-1, size) != eytzinger0_first(size));
-
-		BUG_ON(eytzinger0_prev(eytzinger0_first(size), size)	!= -1);
-		BUG_ON(eytzinger0_next(eytzinger0_last(size), size)	!= -1);
+			pr_info("tree size %u\n", size);
 
 		inorder = 0;
 		eytzinger0_for_each(eytz, size) {
@@ -767,54 +777,191 @@ void eytzinger0_test(void)
 
 			inorder++;
 		}
+		BUG_ON(inorder != size);
+
+		inorder = size - 1;
+		eytzinger0_for_each_prev(eytz, size) {
+			BUG_ON(eytz != eytzinger0_first(size) &&
+			       eytzinger0_next(eytzinger0_prev(eytz, size), size) != eytz);
+
+			inorder--;
+		}
+		BUG_ON(inorder != -1);
 	}
 }
 
-static inline int cmp_u16(const void *_l, const void *_r, size_t size)
+static inline int cmp_u16(const void *_l, const void *_r)
 {
 	const u16 *l = _l, *r = _r;
 
-	return (*l > *r) - (*r - *l);
+	return (*l > *r) - (*r > *l);
 }
 
-static void eytzinger0_find_test_val(u16 *test_array, unsigned nr, u16 search)
+static void eytzinger0_find_test_le(u16 *test_array, unsigned nr, u16 search)
 {
-	int i, c1 = -1, c2 = -1;
-	ssize_t r;
+	int r, s;
+	bool bad;
 
 	r = eytzinger0_find_le(test_array, nr,
 			       sizeof(test_array[0]),
 			       cmp_u16, &search);
-	if (r >= 0)
-		c1 = test_array[r];
-
-	for (i = 0; i < nr; i++)
-		if (test_array[i] <= search && test_array[i] > c2)
-			c2 = test_array[i];
-
-	if (c1 != c2) {
-		eytzinger0_for_each(i, nr)
-			pr_info("[%3u] = %12u", i, test_array[i]);
-		pr_info("find_le(%2u) -> [%2zi] = %2i should be %2i",
-			i, r, c1, c2);
+	if (r >= 0) {
+		if (test_array[r] > search) {
+			bad = true;
+		} else {
+			s = eytzinger0_next(r, nr);
+			bad = s >= 0 && test_array[s] <= search;
+		}
+	} else {
+		s = eytzinger0_last(nr);
+		bad = s >= 0 && test_array[s] <= search;
+	}
+
+	if (bad) {
+		s = -1;
+		eytzinger0_for_each_prev(j, nr) {
+			if (test_array[j] <= search) {
+				s = j;
+				break;
+			}
+		}
+
+		eytzinger0_for_each(j, nr)
+			pr_info("[%3u] = %12u\n", j, test_array[j]);
+		pr_info("find_le(%12u) = %3i should be %3i\n",
+			search, r, s);
+		BUG();
 	}
 }
 
+static void eytzinger0_find_test_gt(u16 *test_array, unsigned nr, u16 search)
+{
+	int r, s;
+	bool bad;
+
+	r = eytzinger0_find_gt(test_array, nr,
+			       sizeof(test_array[0]),
+			       cmp_u16, &search);
+	if (r >= 0) {
+		if (test_array[r] <= search) {
+			bad = true;
+		} else {
+			s = eytzinger0_prev(r, nr);
+			bad = s >= 0 && test_array[s] > search;
+		}
+	} else {
+		s = eytzinger0_first(nr);
+		bad = s >= 0 && test_array[s] > search;
+	}
+
+	if (bad) {
+		s = -1;
+		eytzinger0_for_each(j, nr) {
+			if (test_array[j] > search) {
+				s = j;
+				break;
+			}
+		}
+
+		eytzinger0_for_each(j, nr)
+			pr_info("[%3u] = %12u\n", j, test_array[j]);
+		pr_info("find_gt(%12u) = %3i should be %3i\n",
+			search, r, s);
+		BUG();
+	}
+}
+
+static void eytzinger0_find_test_ge(u16 *test_array, unsigned nr, u16 search)
+{
+	int r, s;
+	bool bad;
+
+	r = eytzinger0_find_ge(test_array, nr,
+			       sizeof(test_array[0]),
+			       cmp_u16, &search);
+	if (r >= 0) {
+		if (test_array[r] < search) {
+			bad = true;
+		} else {
+			s = eytzinger0_prev(r, nr);
+			bad = s >= 0 && test_array[s] >= search;
+		}
+	} else {
+		s = eytzinger0_first(nr);
+		bad = s >= 0 && test_array[s] >= search;
+	}
+
+	if (bad) {
+		s = -1;
+		eytzinger0_for_each(j, nr) {
+			if (test_array[j] >= search) {
+				s = j;
+				break;
+			}
+		}
+
+		eytzinger0_for_each(j, nr)
+			pr_info("[%3u] = %12u\n", j, test_array[j]);
+		pr_info("find_ge(%12u) = %3i should be %3i\n",
+			search, r, s);
+		BUG();
+	}
+}
+
+static void eytzinger0_find_test_eq(u16 *test_array, unsigned nr, u16 search)
+{
+	unsigned r;
+	int s;
+	bool bad;
+
+	r = eytzinger0_find(test_array, nr,
+			    sizeof(test_array[0]),
+			    cmp_u16, &search);
+
+	if (r < nr) {
+		bad = test_array[r] != search;
+	} else {
+		s = eytzinger0_find_le(test_array, nr,
+				       sizeof(test_array[0]),
+				       cmp_u16, &search);
+		bad = s >= 0 && test_array[s] == search;
+	}
+
+	if (bad) {
+		eytzinger0_for_each(j, nr)
+			pr_info("[%3u] = %12u\n", j, test_array[j]);
+		pr_info("find(%12u) = %3i is incorrect\n",
+			search, r);
+		BUG();
+	}
+}
+
+static void eytzinger0_find_test_val(u16 *test_array, unsigned nr, u16 search)
+{
+	eytzinger0_find_test_le(test_array, nr, search);
+	eytzinger0_find_test_gt(test_array, nr, search);
+	eytzinger0_find_test_ge(test_array, nr, search);
+	eytzinger0_find_test_eq(test_array, nr, search);
+}
+
 void eytzinger0_find_test(void)
 {
 	unsigned i, nr, allocated = 1 << 12;
 	u16 *test_array = kmalloc_array(allocated, sizeof(test_array[0]), GFP_KERNEL);
 
 	for (nr = 1; nr < allocated; nr++) {
-		pr_info("testing %u elems", nr);
+		u16 prev = 0;
+
+		pr_info("testing %u elems\n", nr);
 
 		get_random_bytes(test_array, nr * sizeof(test_array[0]));
 		eytzinger0_sort(test_array, nr, sizeof(test_array[0]), cmp_u16, NULL);
 
 		/* verify array is sorted correctly: */
-		eytzinger0_for_each(i, nr)
-			BUG_ON(i != eytzinger0_last(nr) &&
-			       test_array[i] > test_array[eytzinger0_next(i, nr)]);
+		eytzinger0_for_each(j, nr) {
+			BUG_ON(test_array[j] < prev);
+			prev = test_array[j];
+		}
 
 		for (i = 0; i < U16_MAX; i += 1 << 12)
 			eytzinger0_find_test_val(test_array, nr, i);
diff --git a/fs/bcachefs/util.h b/fs/bcachefs/util.h
index f4a4783219d9..7d921fc920a0 100644
--- a/fs/bcachefs/util.h
+++ b/fs/bcachefs/util.h
@@ -406,6 +406,18 @@ u64 bch2_get_random_u64_below(u64);
 void memcpy_to_bio(struct bio *, struct bvec_iter, const void *);
 void memcpy_from_bio(void *, struct bio *, struct bvec_iter);
 
+#ifdef CONFIG_BCACHEFS_DEBUG
+void bch2_corrupt_bio(struct bio *);
+
+static inline void bch2_maybe_corrupt_bio(struct bio *bio, unsigned ratio)
+{
+	if (ratio && !get_random_u32_below(ratio))
+		bch2_corrupt_bio(bio);
+}
+#else
+#define bch2_maybe_corrupt_bio(...)	do {} while (0)
+#endif
+
 static inline void memcpy_u64s_small(void *dst, const void *src,
 				     unsigned u64s)
 {
@@ -419,7 +431,7 @@ static inline void memcpy_u64s_small(void *dst, const void *src,
 static inline void __memcpy_u64s(void *dst, const void *src,
 				 unsigned u64s)
 {
-#ifdef CONFIG_X86_64
+#if defined(CONFIG_X86_64) && !defined(CONFIG_KMSAN)
 	long d0, d1, d2;
 
 	asm volatile("rep ; movsq"
@@ -496,7 +508,7 @@ static inline void __memmove_u64s_up(void *_dst, const void *_src,
 	u64 *dst = (u64 *) _dst + u64s - 1;
 	u64 *src = (u64 *) _src + u64s - 1;
 
-#ifdef CONFIG_X86_64
+#if defined(CONFIG_X86_64) && !defined(CONFIG_KMSAN)
 	long d0, d1, d2;
 
 	asm volatile("std ;\n"
diff --git a/fs/bcachefs/xattr.c b/fs/bcachefs/xattr.c
index aed7c6984173..f9667b944c0d 100644
--- a/fs/bcachefs/xattr.c
+++ b/fs/bcachefs/xattr.c
@@ -523,7 +523,7 @@ static int bch2_xattr_bcachefs_set(const struct xattr_handler *handler,
 		if (ret < 0)
 			goto err_class_exit;
 
-		ret = bch2_opt_check_may_set(c, opt_id, v);
+		ret = bch2_opt_check_may_set(c, NULL, opt_id, v);
 		if (ret < 0)
 			goto err_class_exit;
 
-- 
2.45.3

