On 5/20/19 6:17 PM, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
>
> Teach mkfs to set the DAX flag on the root directory so that all new
> files can be created in dax mode. This is a complement to removing the
> mount option.
>
> Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> ---
> man/man8/mkfs.xfs.8 | 11 +++++++++++
> mkfs/xfs_mkfs.c | 11 +++++++++++
> 2 files changed, 22 insertions(+)
I'll tuck this away for 2024 when we decide what to do about dax.
-Eric
>
> diff --git a/man/man8/mkfs.xfs.8 b/man/man8/mkfs.xfs.8
> index 4b8c78c3..0137f164 100644
> --- a/man/man8/mkfs.xfs.8
> +++ b/man/man8/mkfs.xfs.8
> @@ -391,6 +391,17 @@ All inodes created by
> will have this extent size hint applied.
> The value must be provided in units of filesystem blocks.
> Directories will pass on this hint to newly created children.
> +.TP
> +.BI dax= value
> +All inodes created by
> +.B mkfs.xfs
> +will have the DAX flag set.
> +This means that directories will pass the flag on to newly created files
> +and files will use the DAX IO paths when possible.
> +This value is either 1 to enable the use or 0 to disable.
> +By default,
> +.B mkfs.xfs
> +will not enable DAX mode.
> .RE
> .TP
> .B \-f
> diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
> index 09106648..5b66074d 100644
> --- a/mkfs/xfs_mkfs.c
> +++ b/mkfs/xfs_mkfs.c
> @@ -59,6 +59,7 @@ enum {
> D_PROJINHERIT,
> D_EXTSZINHERIT,
> D_COWEXTSIZE,
> + D_DAX,
> D_MAX_OPTS,
> };
>
> @@ -253,6 +254,7 @@ static struct opt_params dopts = {
> [D_PROJINHERIT] = "projinherit",
> [D_EXTSZINHERIT] = "extszinherit",
> [D_COWEXTSIZE] = "cowextsize",
> + [D_DAX] = "dax",
> },
> .subopt_params = {
> { .index = D_AGCOUNT,
> @@ -368,6 +370,12 @@ static struct opt_params dopts = {
> .maxval = UINT_MAX,
> .defaultval = SUBOPT_NEEDS_VAL,
> },
> + { .index = D_DAX,
> + .conflicts = { { NULL, LAST_CONFLICT } },
> + .minval = 0,
> + .maxval = 1,
> + .defaultval = 1,
> + },
> },
> };
>
> @@ -1465,6 +1473,9 @@ data_opts_parser(
> cli->fsx.fsx_cowextsize = getnum(value, opts, subopt);
> cli->fsx.fsx_xflags |= FS_XFLAG_COWEXTSIZE;
> break;
> + case D_DAX:
> + cli->fsx.fsx_xflags |= FS_XFLAG_DAX;
> + break;
> default:
> return -EINVAL;
> }
>
