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

["Javier González" <javier@javigon.com>]

On 26.06.2020 01:45, Damien Le Moal wrote:
>On 2020/06/25 21:22, Javier González wrote:
>> From: Javier González <javier.gonz@samsung.com>
>>
>> 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@samsung.com>
>> Signed-off-by: SelvaKumar S <selvakuma.s1@samsung.com>
>> Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
>> Signed-off-by: Nitesh Shetty <nj.shetty@samsung.com>
>> ---
>>  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