+ mm-shmem-tmpfs-fallocate-use-file_modified.patch added to mm-hotfixes-unstable branch

+ mm-shmem-tmpfs-fallocate-use-file_modified.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/shmem: tmpfs fallocate use file_modified()
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-shmem-tmpfs-fallocate-use-file_modified.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-shmem-tmpfs-fallocate-use-file_modified.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: Hugh Dickins <hughd@google.com>
Subject: mm/shmem: tmpfs fallocate use file_modified()
Date: Wed, 10 Aug 2022 21:55:36 -0700 (PDT)

5.18 fixed the btrfs and ext4 fallocates to use file_modified(), as xfs
was already doing, to drop privileges: and fstests generic/{683,684,688}
expect this.  There's no need to argue over keep-size allocation (which
could just update ctime): fix shmem_fallocate() to behave the same way.

Link: https://lkml.kernel.org/r/39c5e62-4896-7795-c0a0-f79c50d4909@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Radoslaw Burny <rburny@google.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/shmem.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/mm/shmem.c~mm-shmem-tmpfs-fallocate-use-file_modified
+++ a/mm/shmem.c
@@ -2840,12 +2840,13 @@ static long shmem_fallocate(struct file
 
 	if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + len > inode->i_size)
 		i_size_write(inode, offset + len);
-	inode->i_ctime = current_time(inode);
 undone:
 	spin_lock(&inode->i_lock);
 	inode->i_private = NULL;
 	spin_unlock(&inode->i_lock);
 out:
+	if (!error)
+		file_modified(file);
 	inode_unlock(inode);
 	return error;
 }
_

Patches currently in -mm which might be from hughd@google.com are

mm-shmem-fix-chattr-fsflags-support-in-tmpfs.patch
mm-shmem-tmpfs-fallocate-use-file_modified.patch
mm-shmem-shmem_replace_page-remember-nr_shmem.patch