[PATCH 02/14] fs: lift the FMODE_NOCMTIME check into file_update_time_flags

Christoph Hellwig
2025-11-14T06:27:02Z

FMODE_NOCMTIME used to be just a hack for the legacy XFS handle-based
"invisible I/O", but commit e5e9b24ab8fa ("nfsd: freeze c/mtime updates
with outstanding WRITE_ATTRS delegation") started using it from
generic callers.

I'm not sure other file systems are actually read for this in general,
so the above commit should get a closer look, but for it to make any
sense, file_update_time needs to respect the flag.

Lift the check from file_modified_flags to file_update_time so that
users of file_update_time inherit the behavior and so that all the
checks are done in one place.

Fixes: e5e9b24ab8fa ("nfsd: freeze c/mtime updates with outstanding WRITE_ATTRS delegation")
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/inode.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index 4884ffa931e7..24dab63844db 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -2320,6 +2320,8 @@ static int file_update_time_flags(struct file *file, unsigned int flags)
/* First try to exhaust all avenues to not sync */
if (IS_NOCMTIME(inode))
return 0;
+ if (unlikely(file->f_mode & FMODE_NOCMTIME))
+ return 0;

now = current_time(inode);

@@ -2391,8 +2393,6 @@ static int file_modified_flags(struct file *file, int flags)
ret = file_remove_privs_flags(file, flags);
if (ret)
return ret;
- if (unlikely(file->f_mode & FMODE_NOCMTIME))
- return 0;
return file_update_time_flags(file, flags);
}

--
2.47.3