We added the documentation in ext4_map_blocks() for usage of
EXT4_GET_BLOCKS_QUERY_LAST_IN_LEAF flag. But It's better to add
a WARN_ON_ONCE in case if anyone tries using this flag with CREATE to
avoid a random issue later. Since depth can change with CREATE and it
needs to be re-calculated before using it in there.
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>
---
fs/ext4/extents.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 7683558381dc..ea5158703d2d 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4444,9 +4444,11 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
* need to re-calculate the depth as it might have changed due to block
* allocation.
*/
- if (flags & EXT4_GET_BLOCKS_QUERY_LAST_IN_LEAF)
+ if (flags & EXT4_GET_BLOCKS_QUERY_LAST_IN_LEAF) {
+ WARN_ON_ONCE(flags & EXT4_GET_BLOCKS_CREATE);
if (!err && ex && (ex == EXT_LAST_EXTENT(path[depth].p_hdr)))
map->m_flags |= EXT4_MAP_QUERY_LAST_IN_LEAF;
+ }
ext4_free_ext_path(path);
--
2.49.0
