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From:   Jeff Layton <jlayton@kernel.org>
Date:   Tue, 25 Jul 2023 10:58:17 -0400
Subject: [PATCH v6 4/7] tmpfs: add support for multigrain timestamps
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        Jeff Layton <jlayton@kernel.org>
Precedence: bulk

Enable multigrain timestamps, which should ensure that there is an
apparent change to the timestamp whenever it has been written after
being actively observed via getattr.

tmpfs only requires the FS_MGTIME flag.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 mm/shmem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index 654d9a585820..b6019c905058 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -4264,7 +4264,7 @@ static struct file_system_type shmem_fs_type = {
 #endif
 	.kill_sb	= kill_litter_super,
 #ifdef CONFIG_SHMEM
-	.fs_flags	= FS_USERNS_MOUNT | FS_ALLOW_IDMAP,
+	.fs_flags	= FS_USERNS_MOUNT | FS_ALLOW_IDMAP | FS_MGTIME,
 #else
 	.fs_flags	= FS_USERNS_MOUNT,
 #endif

-- 
2.41.0