[PATCH] btrfs: remove verity Merkle folio from page cache on error

[Yichong Chen]

btrfs_read_merkle_tree_page() allocates a folio and adds it to the
page cache before reading the Merkle tree data from btree items.

If read_key_bytes() fails, the folio is still locked and present in the
page cache. Drop it from the page cache and unlock it before releasing the
allocation reference so a later read can retry instead of finding a locked,
not-uptodate folio.

Fixes: 06ed09351b67 ("btrfs: convert btrfs_read_merkle_tree_page() to use a folio")
Signed-off-by: Yichong Chen <chenyichong@xxxxxxxxxxxxx>
---
 fs/btrfs/verity.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/btrfs/verity.c b/fs/btrfs/verity.c
index 983365a73541..99468791a98e 100644
--- a/fs/btrfs/verity.c
+++ b/fs/btrfs/verity.c
@@ -753,6 +753,8 @@ static struct page *btrfs_read_merkle_tree_page(struct inode *inode,
 	ret = read_key_bytes(BTRFS_I(inode), BTRFS_VERITY_MERKLE_ITEM_KEY, off,
 			     folio_address(folio), PAGE_SIZE, folio);
 	if (ret < 0) {
+		filemap_remove_folio(folio);
+		folio_unlock(folio);
 		folio_put(folio);
 		return ERR_PTR(ret);
 	}
-- 
2.51.0