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To:     Michal Suchanek <msuchanek@suse.de>, linux-xfs@vger.kernel.org,
        linux-ext4@vger.kernel.org
Cc:     Theodore Ts'o <tytso@mit.edu>,
        Andreas Dilger <adilger.kernel@dilger.ca>,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
        Ira Weiny <ira.weiny@intel.com>, Jan Kara <jack@suse.cz>,
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References: <cover.1604948373.git.msuchanek@suse.de>
 <f9f7ba25e97dacd92c09eb3ee6a4aca8b4f72b00.1604948373.git.msuchanek@suse.de>
From:   Eric Sandeen <sandeen@sandeen.net>
Subject: Re: [PATCH 1/2] xfs: show the dax option in mount options.
Message-ID: <5e266714-5598-c413-6129-d0a9913ca5b9@sandeen.net>
Date:   Mon, 9 Nov 2020 13:24:03 -0600
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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 }
>  	};
>