From 980f7437e2588d100456640cb863908a3cc6fc77 Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kent.overstreet@linux.dev>
Date: Mon, 24 Oct 2022 11:34:07 -0400
Subject: [PATCH] Update bcachefs sources to 61ebcb532a bcachefs: Fix for
 allocating before backpointers have been checked

---
 .bcachefs_revision             |  2 +-
 libbcachefs/alloc_foreground.c | 23 +++++++++++++++++++++++
 libbcachefs/btree_iter.c       |  8 ++------
 libbcachefs/btree_iter.h       | 17 +++++++++++++++--
 libbcachefs/fs-io.c            | 19 +++++++++++++++----
 libbcachefs/io.c               |  3 +++
 6 files changed, 59 insertions(+), 13 deletions(-)

diff --git a/.bcachefs_revision b/.bcachefs_revision
index 206b9d4d..3a147c61 100644
--- a/.bcachefs_revision
+++ b/.bcachefs_revision
@@ -1 +1 @@
-70fa0c1ff48feba041a8243b1a52ee57cffe1e0e
+61ebcb532a1266e5e36f354858b552e2a4fb9925
diff --git a/libbcachefs/alloc_foreground.c b/libbcachefs/alloc_foreground.c
index a9e0c739..186c2ed4 100644
--- a/libbcachefs/alloc_foreground.c
+++ b/libbcachefs/alloc_foreground.c
@@ -14,6 +14,7 @@
 #include "bcachefs.h"
 #include "alloc_background.h"
 #include "alloc_foreground.h"
+#include "backpointers.h"
 #include "btree_iter.h"
 #include "btree_update.h"
 #include "btree_gc.h"
@@ -333,6 +334,28 @@ static struct open_bucket *try_alloc_bucket(struct btree_trans *trans, struct bc
 		goto err;
 	}
 
+	if (!test_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags)) {
+		struct bch_backpointer bp;
+		u64 bp_offset = 0;
+
+		ret = bch2_get_next_backpointer(trans, POS(ca->dev_idx, b), -1,
+						&bp_offset, &bp, 0);
+		if (ret) {
+			ob = ERR_PTR(ret);
+			goto err;
+		}
+
+		if (bp_offset != U64_MAX) {
+			/*
+			 * Bucket may have data in it - we don't call
+			 * bc2h_trans_inconnsistent() because fsck hasn't
+			 * finished yet
+			 */
+			ob = NULL;
+			goto err;
+		}
+	}
+
 	ob = __try_alloc_bucket(c, ca, b, reserve, &a,
 				skipped_open,
 				skipped_need_journal_commit,
diff --git a/libbcachefs/btree_iter.c b/libbcachefs/btree_iter.c
index da116153..99a92a89 100644
--- a/libbcachefs/btree_iter.c
+++ b/libbcachefs/btree_iter.c
@@ -1222,19 +1222,15 @@ struct btree_path *__bch2_btree_path_make_mut(struct btree_trans *trans,
 }
 
 struct btree_path * __must_check
-bch2_btree_path_set_pos(struct btree_trans *trans,
+__bch2_btree_path_set_pos(struct btree_trans *trans,
 		   struct btree_path *path, struct bpos new_pos,
-		   bool intent, unsigned long ip)
+		   bool intent, unsigned long ip, int cmp)
 {
-	int cmp = bpos_cmp(new_pos, path->pos);
 	unsigned l = path->level;
 
 	EBUG_ON(trans->restarted);
 	EBUG_ON(!path->ref);
 
-	if (!cmp)
-		return path;
-
 	path = bch2_btree_path_make_mut(trans, path, intent, ip);
 
 	path->pos = new_pos;
diff --git a/libbcachefs/btree_iter.h b/libbcachefs/btree_iter.h
index 0775cfa2..8c35d7d4 100644
--- a/libbcachefs/btree_iter.h
+++ b/libbcachefs/btree_iter.h
@@ -146,8 +146,21 @@ bch2_btree_path_make_mut(struct btree_trans *trans,
 }
 
 struct btree_path * __must_check
-bch2_btree_path_set_pos(struct btree_trans *, struct btree_path *,
-			struct bpos, bool, unsigned long);
+__bch2_btree_path_set_pos(struct btree_trans *, struct btree_path *,
+			struct bpos, bool, unsigned long, int);
+
+static inline struct btree_path * __must_check
+bch2_btree_path_set_pos(struct btree_trans *trans,
+		   struct btree_path *path, struct bpos new_pos,
+		   bool intent, unsigned long ip)
+{
+	int cmp = bpos_cmp(new_pos, path->pos);
+
+	return cmp
+		? __bch2_btree_path_set_pos(trans, path, new_pos, intent, ip, cmp)
+		: path;
+}
+
 int __must_check bch2_btree_path_traverse(struct btree_trans *,
 					  struct btree_path *, unsigned);
 struct btree_path *bch2_path_get(struct btree_trans *, enum btree_id, struct bpos,
diff --git a/libbcachefs/fs-io.c b/libbcachefs/fs-io.c
index 706180b9..3900995d 100644
--- a/libbcachefs/fs-io.c
+++ b/libbcachefs/fs-io.c
@@ -1666,10 +1666,21 @@ static int __bch2_buffered_write(struct bch_inode_info *inode,
 				goto out;
 		}
 
+		/*
+		 * XXX: per POSIX and fstests generic/275, on -ENOSPC we're
+		 * supposed to write as much as we have disk space for.
+		 *
+		 * On failure here we should still write out a partial page if
+		 * we aren't completely out of disk space - we don't do that
+		 * yet:
+		 */
 		ret = bch2_page_reservation_get(c, inode, page, &res,
 						pg_offset, pg_len);
-		if (ret)
-			goto out;
+		if (unlikely(ret)) {
+			if (!reserved)
+				goto out;
+			break;
+		}
 
 		reserved += pg_len;
 	}
@@ -1678,10 +1689,10 @@ static int __bch2_buffered_write(struct bch_inode_info *inode,
 		for (i = 0; i < nr_pages; i++)
 			flush_dcache_page(pages[i]);
 
-	while (copied < len) {
+	while (copied < reserved) {
 		struct page *page = pages[(offset + copied) >> PAGE_SHIFT];
 		unsigned pg_offset = (offset + copied) & (PAGE_SIZE - 1);
-		unsigned pg_len = min_t(unsigned, len - copied,
+		unsigned pg_len = min_t(unsigned, reserved - copied,
 					PAGE_SIZE - pg_offset);
 		unsigned pg_copied = copy_page_from_iter_atomic(page,
 						pg_offset, pg_len, iter);
diff --git a/libbcachefs/io.c b/libbcachefs/io.c
index 5971569e..60a14fa1 100644
--- a/libbcachefs/io.c
+++ b/libbcachefs/io.c
@@ -325,6 +325,9 @@ int bch2_extent_update(struct btree_trans *trans,
 			new_inode->v.bi_size = cpu_to_le64(new_i_size);
 
 		le64_add_cpu(&new_inode->v.bi_sectors, i_sectors_delta);
+
+		new_inode->k.p.snapshot = iter->snapshot;
+
 		ret = bch2_trans_update(trans, &inode_iter, &new_inode->k_i, 0);
 		if (unlikely(ret))
 			goto err;