2020-04-27 01:35:21

by Harshad Shirwadkar

[permalink] [raw]
Subject: [PATCH v3] ext4: don't ignore return values from ext4_ext_dirty()

Don't ignore return values from ext4_ext_dirty, since the errors
indicate valid failures below Ext4. In all of the other instances of
ext4_ext_dirty calls, the error return value is handled in some
way. This patch makes those remaining couple of places to handle
ext4_ext_dirty errors as well. In case of ext4_split_extent_at(), the
ignorance of return value is intentional. The reason is that we are
already in error path and there isn't much we can do if ext4_ext_dirty
returns error. This patch adds a comment for that case explaining why
we ignore the return value.

In the longer run, we probably should
make sure that errors from other mark_dirty routines are handled as
well.

Ran gce-xfstests smoke tests and verified that there were no
regressions.

Signed-off-by: Harshad Shirwadkar <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
---
Changes since V2:
* Reorganized commit message

Changes since V1:
* Fixed incorrect return value handling in ext4_split_extent_at()

fs/ext4/extents.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index f2b577b315a0..6425f4f9a197 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -3244,6 +3244,10 @@ static int ext4_split_extent_at(handle_t *handle,

fix_extent_len:
ex->ee_len = orig_ex.ee_len;
+ /*
+ * Ignore ext4_ext_dirty return value since we are already in error path
+ * and err is a non-zero error code.
+ */
ext4_ext_dirty(handle, inode, path + path->p_depth);
return err;
}
@@ -3503,7 +3507,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
}
if (allocated) {
/* Mark the block containing both extents as dirty */
- ext4_ext_dirty(handle, inode, path + depth);
+ err = ext4_ext_dirty(handle, inode, path + depth);

/* Update path to point to the right extent */
path[depth].p_ext = abut_ex;
--
2.26.2.303.gf8c07b1a785-goog