4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Roman Pen <roman.penyaev@xxxxxxxxxxxxxxxx>
commit 03e916fa8b5577d85471452a3d0c5738aa658dae upstream.
Inside ext4_ext_shift_extents() function ext4_find_extent() is called
without EXT4_EX_NOCACHE flag, which should prevent cache population.
This leads to oudated offsets in the extents tree and wrong blocks
afterwards.
Patch fixes the problem providing EXT4_EX_NOCACHE flag for each
ext4_find_extents() call inside ext4_ext_shift_extents function.
Fixes: 331573febb6a2
Signed-off-by: Roman Pen <roman.penyaev@xxxxxxxxxxxxxxxx>
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Cc: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>
Cc: Andreas Dilger <adilger.kernel@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ext4/extents.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -5344,7 +5344,8 @@ ext4_ext_shift_extents(struct inode *ino
ext4_lblk_t stop, *iterator, ex_start, ex_end;
/* Let path point to the last extent */
- path = ext4_find_extent(inode, EXT_MAX_BLOCKS - 1, NULL, 0);
+ path = ext4_find_extent(inode, EXT_MAX_BLOCKS - 1, NULL,
+ EXT4_EX_NOCACHE);
if (IS_ERR(path))
return PTR_ERR(path);
@@ -5360,7 +5361,8 @@ ext4_ext_shift_extents(struct inode *ino
* sure the hole is big enough to accommodate the shift.
*/
if (SHIFT == SHIFT_LEFT) {
- path = ext4_find_extent(inode, start - 1, &path, 0);
+ path = ext4_find_extent(inode, start - 1, &path,
+ EXT4_EX_NOCACHE);
if (IS_ERR(path))
return PTR_ERR(path);
depth = path->p_depth;
@@ -5398,7 +5400,8 @@ ext4_ext_shift_extents(struct inode *ino
* becomes NULL to indicate the end of the loop.
*/
while (iterator && start <= stop) {
- path = ext4_find_extent(inode, *iterator, &path, 0);
+ path = ext4_find_extent(inode, *iterator, &path,
+ EXT4_EX_NOCACHE);
if (IS_ERR(path))
return PTR_ERR(path);
depth = path->p_depth;