Re: [PATCH V8 04/11] fs/xfs: Change XFS_MOUNT_DAX to XFS_MOUNT_DAX_ALWAYS

From: Dave Chinner
Date: Sun Apr 19 2020 - 22:16:17 EST


On Tue, Apr 14, 2020 at 11:45:16PM -0700, ira.weiny@xxxxxxxxx wrote:
> From: Ira Weiny <ira.weiny@xxxxxxxxx>
>
> In prep for the new tri-state mount option which then introduces
> XFS_MOUNT_DAX_NEVER.
>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> ---
> fs/xfs/xfs_iops.c | 2 +-
> fs/xfs/xfs_mount.h | 2 +-
> fs/xfs/xfs_super.c | 8 ++++----
> 3 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index 81f2f93caec0..a6e634631da8 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -1248,7 +1248,7 @@ xfs_inode_supports_dax(
> return false;
>
> /* DAX mount option or DAX iflag must be set. */
> - if (!(mp->m_flags & XFS_MOUNT_DAX) &&
> + if (!(mp->m_flags & XFS_MOUNT_DAX_ALWAYS) &&
> !(ip->i_d.di_flags2 & XFS_DIFLAG2_DAX))
> return false;
>
> diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
> index 88ab09ed29e7..54bd74088936 100644
> --- a/fs/xfs/xfs_mount.h
> +++ b/fs/xfs/xfs_mount.h
> @@ -233,7 +233,7 @@ typedef struct xfs_mount {
> allocator */
> #define XFS_MOUNT_NOATTR2 (1ULL << 25) /* disable use of attr2 format */
>
> -#define XFS_MOUNT_DAX (1ULL << 62) /* TEST ONLY! */
> +#define XFS_MOUNT_DAX_ALWAYS (1ULL << 62) /* TEST ONLY! */

As this is going to be permanent, please remove the "Test only"
comment and renumber the bits used down to 26. - the high bit was
used only to keep it out of the ranges that permanent mount option
flags used...

Cheers,

Dave.
--
Dave Chinner
david@xxxxxxxxxxxxx