Re: [PATCH 5/6] block: add zone attr. to zone mgmt IOCTL struct

[Javier González <javier@xxxxxxxxxxx>]

On 26.06.2020 01:45, Damien Le Moal wrote:
> On 2020/06/25 21:22, Javier González wrote:
> > From: Javier González <javier.gonz@xxxxxxxxxxx>
> >
> > Add zone attributes field to the blk_zone structure. Use ZNS attributes
> > as base for zoned block devices in general.
> >
> > Signed-off-by: Javier González <javier.gonz@xxxxxxxxxxx>
> > Signed-off-by: SelvaKumar S <selvakuma.s1@xxxxxxxxxxx>
> > Signed-off-by: Kanchan Joshi <joshi.k@xxxxxxxxxxx>
> > Signed-off-by: Nitesh Shetty <nj.shetty@xxxxxxxxxxx>
> > ---
> >  drivers/nvme/host/zns.c       |  1 +
> >  include/uapi/linux/blkzoned.h | 13 ++++++++++++-
> >  2 files changed, 13 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/nvme/host/zns.c b/drivers/nvme/host/zns.c
> > index 258d03610cc0..7d8381fe7665 100644
> > --- a/drivers/nvme/host/zns.c
> > +++ b/drivers/nvme/host/zns.c
> > @@ -195,6 +195,7 @@ static int nvme_zone_parse_entry(struct nvme_ns *ns,
> >  	zone.capacity = nvme_lba_to_sect(ns, le64_to_cpu(entry->zcap));
> >  	zone.start = nvme_lba_to_sect(ns, le64_to_cpu(entry->zslba));
> >  	zone.wp = nvme_lba_to_sect(ns, le64_to_cpu(entry->wp));
> > +	zone.attr = entry->za;
> >
> >  	return cb(&zone, idx, data);
> >  }
> > diff --git a/include/uapi/linux/blkzoned.h b/include/uapi/linux/blkzoned.h
> > index 0c49a4b2ce5d..2e43a00e3425 100644
> > --- a/include/uapi/linux/blkzoned.h
> > +++ b/include/uapi/linux/blkzoned.h
> > @@ -82,6 +82,16 @@ enum blk_zone_report_flags {
> >  	BLK_ZONE_REP_CAPACITY	= (1 << 0),
> >  };
> >
> > +/**
> > + * Zone Attributes
>
> This is a user interface file. Please document the meaning of each attribute.

Sure.

> > + */
> > +enum blk_zone_attr {
> > +	BLK_ZONE_ATTR_ZFC	= 1 << 0,
> > +	BLK_ZONE_ATTR_FZR	= 1 << 1,
> > +	BLK_ZONE_ATTR_RZR	= 1 << 2,
> > +	BLK_ZONE_ATTR_ZDEV	= 1 << 7,
> These are ZNS specific, right ? Integrating the 2 ZBC/ZAC attributes in this
> list would be nice, namely non_seq and reset. That will imply patching sd.c.

Of course. I will look at non_seq and reset. Any other that should go
in here?

> > +};
> > +
> >  /**
> >   * struct blk_zone - Zone descriptor for BLKREPORTZONE ioctl.
> >   *
> > @@ -108,7 +118,8 @@ struct blk_zone {
> >  	__u8	cond;		/* Zone condition */
> >  	__u8	non_seq;	/* Non-sequential write resources active */
> >  	__u8	reset;		/* Reset write pointer recommended */
> > -	__u8	resv[4];
> > +	__u8	attr;		/* Zone attributes */
> > +	__u8	resv[3];
> >  	__u64	capacity;	/* Zone capacity in number of sectors */
> >  	__u8	reserved[24];
> >  };
>
> You are missing a BLK_ZONE_REP_ATTR report flag to indicate to the user that the
> attr field is present, used and valid.
>
> enum blk_zone_report_flags {
> 	BLK_ZONE_REP_CAPACITY	= (1 << 0),
> +	BLK_ZONE_REP_ATTR	= (1 << 1),
> };
>
> is I think needed.

Good point. I will add that on a V2.

Javier