Re: [PATCH 1/2] xfs: show the dax option in mount options.

Eric Sandeen
2020-11-09T19:24:06Z

On 11/9/20 1:10 PM, Michal Suchanek wrote:
> xfs accepts both dax and dax_enum but shows only dax_enum. Show both
> options.

Should probably indicate why this is needed in the changelog.

> Fixes: 8d6c3446ec23 ("fs/xfs: Make DAX mount option a tri-state")
> Signed-off-by: Michal Suchanek <msuchanek@suse.de>

This seems ok to me. I wanted to make sure that "mount -o dax,dax=always"
was accepted properly, because a remount looks to /proc/mounts for existing
options and re-uses what it finds. It does seem to work correctly.

It's a little weird to emit 2 equivalent options when only one was given, but if
legacy apps rely on finding a bare "dax," then I guess it seems harmless enough...

Reviewed-by: Eric Sandeen <sandeen@redhat.com>

> ---
> fs/xfs/xfs_super.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index e3e229e52512..a3b00003840d 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -163,7 +163,7 @@ xfs_fs_show_options(
> { XFS_MOUNT_GRPID, ",grpid" },
> { XFS_MOUNT_DISCARD, ",discard" },
> { XFS_MOUNT_LARGEIO, ",largeio" },
> - { XFS_MOUNT_DAX_ALWAYS, ",dax=always" },
> + { XFS_MOUNT_DAX_ALWAYS, ",dax,dax=always" },
> { XFS_MOUNT_DAX_NEVER, ",dax=never" },
> { 0, NULL }
> };
>