Update bcachefs sources to 6c3c2a24c61d bcachefs: Fix possible corruption on repeated mmap writes

.bcachefs_revision

@@ -1 +1 @@
-682cbaf658f5fde86172e02ffdac0f65650f9fa1
+6c3c2a24c61ddc23a6bbdf604b88262da0cd2d9c

libbcachefs/vfs/buffered.c

@@ -598,6 +598,7 @@ static int __bch2_writepage(struct folio *folio,
 do_io:
 	f_sectors = folio_sectors(folio);
 	s = bch2_folio(folio);
+	BUG_ON(!s);
 
 	if (f_sectors > w->tmp_sectors) {
 		kfree(w->tmp);
@@ -829,7 +830,7 @@ int bch2_write_end(
 	struct bch_inode_info *inode = to_bch_ei(mapping->host);
 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
 	struct bch2_folio_reservation *res = fsdata;
-	unsigned offset = pos - folio_pos(folio);
+	size_t offset = pos - folio_pos(folio);
 
 	BUG_ON(offset + copied > folio_size(folio));
 
@@ -886,8 +887,9 @@ static int __bch2_buffered_write(struct bch_fs *c,
 	struct bch2_folio_reservation res;
 	folios fs;
 	struct folio *f;
-	unsigned copied = 0, f_offset, f_copied;
-	u64 end = pos + len, f_pos, f_len;
+	unsigned copied = 0, f_copied;
+	size_t f_offset, f_len;
+	u64 end = pos + len, f_pos;
 	loff_t last_folio_pos = inode->v.i_size;
 	int ret = 0;
 

libbcachefs/vfs/fs.c

@@ -1498,7 +1498,7 @@ static const struct address_space_operations bch_address_space_operations = {
 	.read_folio	= bch2_read_folio,
 	.writepages	= bch2_writepages,
 	.readahead	= bch2_readahead,
-	.dirty_folio	= filemap_dirty_folio,
+	.dirty_folio	= bch2_vfs_dirty_folio,
 	.write_begin	= bch2_write_begin,
 	.write_end	= bch2_write_end,
 	.invalidate_folio = bch2_invalidate_folio,

libbcachefs/vfs/pagecache.c

@@ -361,14 +361,14 @@ int bch2_get_folio_disk_reservation(struct bch_fs *c,
 				struct bch_inode_info *inode,
 				struct folio *folio, bool check_enospc)
 {
-	struct bch_folio *s = bch2_folio_create(folio, 0);
+	struct bch_folio *s = bch2_folio(folio);
 	unsigned nr_replicas = inode_nr_replicas(c, inode);
 	struct disk_reservation disk_res = { 0 };
 	unsigned i, sectors = folio_sectors(folio), disk_res_sectors = 0;
 	int ret;
 
-	if (!s)
-		return -ENOMEM;
+	BUG_ON(!s);
+	EBUG_ON(!s->uptodate);
 
 	for (i = 0; i < sectors; i++)
 		disk_res_sectors += sectors_to_reserve(&s->s[i], nr_replicas);
@@ -399,21 +399,19 @@ void bch2_folio_reservation_put(struct bch_fs *c,
 	bch2_quota_reservation_put(c, inode, &res->quota);
 }
 
-static int __bch2_folio_reservation_get(struct bch_fs *c,
+static ssize_t __bch2_folio_reservation_get(struct bch_fs *c,
 			struct bch_inode_info *inode,
 			struct folio *folio,
 			struct bch2_folio_reservation *res,
 			size_t offset, size_t len,
 			bool partial)
 {
-	struct bch_folio *s = bch2_folio_create(folio, 0);
+	struct bch_folio *s = bch2_folio(folio);
 	unsigned i, disk_sectors = 0, quota_sectors = 0;
 	size_t reserved = len;
 	int ret;
 
-	if (!s)
-		return -ENOMEM;
-
+	BUG_ON(!s);
 	BUG_ON(!s->uptodate);
 
 	for (i = round_down(offset, block_bytes(c)) >> 9;
@@ -462,13 +460,54 @@ static int __bch2_folio_reservation_get(struct bch_fs *c,
 	return partial ? reserved : 0;
 }
 
+static int bch2_folio_reservation_get_nofail(struct bch_fs *c,
+			struct bch_inode_info *inode,
+			struct folio *folio,
+			struct bch2_folio_reservation *res,
+			size_t offset, size_t len)
+{
+	struct bch_folio *s = bch2_folio(folio);
+	unsigned i, disk_sectors = 0, quota_sectors = 0;
+	struct disk_reservation disk_res = {};
+	int ret;
+
+	BUG_ON(!s);
+	BUG_ON(!s->uptodate);
+
+	for (i = round_down(offset, block_bytes(c)) >> 9;
+	     i < round_up(offset + len, block_bytes(c)) >> 9;
+	     i++) {
+		disk_sectors += sectors_to_reserve(&s->s[i], res->disk.nr_replicas);
+		quota_sectors += s->s[i].state == SECTOR_unallocated;
+	     }
+
+	if (disk_sectors) {
+		ret = bch2_disk_reservation_add(c, &disk_res, disk_sectors,
+				BCH_DISK_RESERVATION_NOFAIL);
+		if (unlikely(ret))
+			return ret;
+	}
+
+	if (quota_sectors) {
+		/* FIXME: we'll need to make sure this won't fail with -ENOMEM */
+		ret = bch2_quota_reservation_add(c, inode, &res->quota, quota_sectors, false);
+		if (unlikely(ret)) {
+			bch2_disk_reservation_put(c, &disk_res);
+			return ret;
+		}
+	}
+
+	res->disk.sectors += disk_res.sectors;
+	return 0;
+}
+
 int bch2_folio_reservation_get(struct bch_fs *c,
 			struct bch_inode_info *inode,
 			struct folio *folio,
 			struct bch2_folio_reservation *res,
 			size_t offset, size_t len)
 {
-	return __bch2_folio_reservation_get(c, inode, folio, res, offset, len, false);
+	return (int)__bch2_folio_reservation_get(c, inode, folio, res, offset, len, false);
 }
 
 ssize_t bch2_folio_reservation_get_partial(struct bch_fs *c,
@@ -508,11 +547,26 @@ static void bch2_clear_folio_bits(struct folio *folio)
 	bch2_folio_release(folio);
 }
 
-void bch2_set_folio_dirty(struct bch_fs *c,
+bool bch2_vfs_dirty_folio(struct address_space *mapping, struct folio *folio)
+{
+	struct bch_inode_info *inode = to_bch_ei(mapping->host);
+	struct bch_fs *c = inode->v.i_sb->s_fs_info;
+	struct bch2_folio_reservation res;
+
+	loff_t file_size = i_size_read(&inode->v);
+	size_t dirty_bytes = min_t(size_t, folio_size(folio),
+		round_up(file_size, block_bytes(c)) - folio_pos(folio));
+
+	bch2_folio_reservation_init(c, inode, &res);
+	BUG_ON(bch2_folio_reservation_get_nofail(c, inode, folio, &res, 0, dirty_bytes));
+	return bch2_set_folio_dirty(c, inode, folio, &res, 0, dirty_bytes);
+}
+
+bool bch2_set_folio_dirty(struct bch_fs *c,
 			  struct bch_inode_info *inode,
 			  struct folio *folio,
 			  struct bch2_folio_reservation *res,
-			  unsigned offset, unsigned len)
+			  size_t offset, size_t len)
 {
 	struct bch_folio *s = bch2_folio(folio);
 	unsigned i, dirty_sectors = 0;
@@ -520,7 +574,9 @@ void bch2_set_folio_dirty(struct bch_fs *c,
 	WARN_ON((u64) folio_pos(folio) + offset + len >
 		round_up((u64) i_size_read(&inode->v), block_bytes(c)));
 
+	BUG_ON(!s);
 	BUG_ON(!s->uptodate);
+	EBUG_ON(round_up(offset + len, block_bytes(c)) >> 9 > UINT_MAX);
 
 	scoped_guard(spinlock, &s->lock)
 		for (i = round_down(offset, block_bytes(c)) >> 9;
@@ -546,7 +602,8 @@ void bch2_set_folio_dirty(struct bch_fs *c,
 	bch2_i_sectors_acct(c, inode, &res->quota, dirty_sectors);
 
 	if (!folio_test_dirty(folio))
-		filemap_dirty_folio(inode->v.i_mapping, folio);
+		return filemap_dirty_folio(inode->v.i_mapping, folio);
+	return false;
 }
 
 vm_fault_t bch2_page_fault(struct vm_fault *vmf)
@@ -598,7 +655,7 @@ vm_fault_t bch2_page_mkwrite(struct vm_fault *vmf)
 	vm_fault_t ret;
 
 	loff_t file_offset = round_down(vmf->pgoff << PAGE_SHIFT, block_bytes(c));
-	unsigned offset = file_offset - folio_pos(folio);
+	size_t offset = file_offset - folio_pos(folio);
 	unsigned len = max(PAGE_SIZE, block_bytes(c));
 
 	BUG_ON(offset + len > folio_size(folio));

libbcachefs/vfs/pagecache.h

@@ -153,11 +153,12 @@ ssize_t bch2_folio_reservation_get_partial(struct bch_fs *,
 			struct bch2_folio_reservation *,
 			size_t, size_t);
 
-void bch2_set_folio_dirty(struct bch_fs *,
+bool bch2_vfs_dirty_folio(struct address_space *mapping, struct folio *folio);
+bool bch2_set_folio_dirty(struct bch_fs *,
 			  struct bch_inode_info *,
 			  struct folio *,
 			  struct bch2_folio_reservation *,
-			  unsigned, unsigned);
+			  size_t, size_t);
 
 vm_fault_t bch2_page_fault(struct vm_fault *);
 vm_fault_t bch2_page_mkwrite(struct vm_fault *);