Re: [PATCH 07/29] xfs: factor out a xfs_setup_dax_always helper

Darrick J. Wong
2021-11-17T17:31:13Z

On Tue, Nov 09, 2021 at 09:32:47AM +0100, Christoph Hellwig wrote:
> Factor out another DAX setup helper to simplify future changes. Also
> move the experimental warning after the checks to not clutter the log
> too much if the setup failed.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> ---
> fs/xfs/xfs_super.c | 47 +++++++++++++++++++++++++++-------------------
> 1 file changed, 28 insertions(+), 19 deletions(-)
>
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index e21459f9923a8..875fd3151d6c9 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -340,6 +340,32 @@ xfs_buftarg_is_dax(
> bdev_nr_sectors(bt->bt_bdev));
> }
>
> +static int
> +xfs_setup_dax_always(
> + struct xfs_mount *mp)
> +{
> + struct super_block *sb = mp->m_super;
> +
> + if (!xfs_buftarg_is_dax(sb, mp->m_ddev_targp) &&
> + (!mp->m_rtdev_targp || !xfs_buftarg_is_dax(sb, mp->m_rtdev_targp))) {
> + xfs_alert(mp,
> + "DAX unsupported by block device. Turning off DAX.");
> + goto disable_dax;
> + }
> +
> + if (xfs_has_reflink(mp)) {
> + xfs_alert(mp, "DAX and reflink cannot be used together!");
> + return -EINVAL;
> + }
> +
> + xfs_warn(mp, "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
> + return 0;
> +
> +disable_dax:
> + xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
> + return 0;
> +}
> +
> STATIC int
> xfs_blkdev_get(
> xfs_mount_t *mp,
> @@ -1593,26 +1619,9 @@ xfs_fs_fill_super(
> sb->s_flags |= SB_I_VERSION;
>
> if (xfs_has_dax_always(mp)) {
> - bool rtdev_is_dax = false, datadev_is_dax;
> -
> - xfs_warn(mp,
> - "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
> -
> - datadev_is_dax = xfs_buftarg_is_dax(sb, mp->m_ddev_targp);
> - if (mp->m_rtdev_targp)
> - rtdev_is_dax = xfs_buftarg_is_dax(sb,
> - mp->m_rtdev_targp);
> - if (!rtdev_is_dax && !datadev_is_dax) {
> - xfs_alert(mp,
> - "DAX unsupported by block device. Turning off DAX.");
> - xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
> - }
> - if (xfs_has_reflink(mp)) {
> - xfs_alert(mp,
> - "DAX and reflink cannot be used together!");
> - error = -EINVAL;
> + error = xfs_setup_dax_always(mp);
> + if (error)
> goto out_filestream_unmount;
> - }
> }
>
> if (xfs_has_discard(mp)) {
> --
> 2.30.2
>