Re: dm sysfs: use default_groups in kobj_type

[Mike Snitzer <snitzer@redhat.com>]

On Thu, Jan 06 2022 at  5:02P -0500,
Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote:

> There are currently 2 ways to create a set of sysfs files for a
> kobj_type, through the default_attrs field, and the default_groups
> field.  Move the dm sysfs code to use default_groups field which has
> been the preferred way since aa30f47cf666 ("kobject: Add support for
> default attribute groups to kobj_type") so that we can soon get rid of
> the obsolete default_attrs field.
> 
> Cc: Alasdair Kergon <agk@redhat.com>
> Cc: Mike Snitzer <snitzer@redhat.com>
> Cc: dm-devel@redhat.com
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
>  drivers/md/dm-sysfs.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/md/dm-sysfs.c b/drivers/md/dm-sysfs.c
> index a05fcd50e1b9..e28c92478536 100644
> --- a/drivers/md/dm-sysfs.c
> +++ b/drivers/md/dm-sysfs.c
> @@ -112,6 +112,7 @@ static struct attribute *dm_attrs[] = {
>  	&dm_attr_rq_based_seq_io_merge_deadline.attr,
>  	NULL,
>  };
> +ATTRIBUTE_GROUPS(dm);

Bit strange to pass "dm" but then have ATTRIBUTE_GROUPS assume dm_attrs defined.
Feels like it'll invite janitors sending patches, that they never
compile, to remove dm_attrs.

>  
>  static const struct sysfs_ops dm_sysfs_ops = {
>  	.show	= dm_attr_show,
> @@ -120,7 +121,7 @@ static const struct sysfs_ops dm_sysfs_ops = {
>  
>  static struct kobj_type dm_ktype = {
>  	.sysfs_ops	= &dm_sysfs_ops,
> -	.default_attrs	= dm_attrs,
> +	.default_groups	= dm_groups,
>  	.release	= dm_kobject_release,
>  };
>  
> -- 
> 2.34.1
> 

But I've picked this patch up for 5.17.  Thanks.