Re: [PATCH v3 2/4] block: add support for zone offline transition

[Damien Le Moal <Damien.LeMoal@wdc.com>]

On 2020/07/02 18:25, Javier González wrote:
> From: Javier González <javier.gonz@samsung.com>
> 
> Add support for offline transition on the zoned block device. Use the
> existing feature flags for the underlying driver to report support for
> the feature, as currently this transition is only supported in ZNS and
> not in ZAC/ZBC
> 
> 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>
> ---
>  block/blk-core.c              | 2 ++
>  block/blk-zoned.c             | 8 +++++++-
>  drivers/nvme/host/core.c      | 3 +++
>  drivers/nvme/host/zns.c       | 2 +-
>  include/linux/blk_types.h     | 3 +++
>  include/linux/blkdev.h        | 1 -
>  include/uapi/linux/blkzoned.h | 6 ++++++
>  7 files changed, 22 insertions(+), 3 deletions(-)
> 
> diff --git a/block/blk-core.c b/block/blk-core.c
> index 03252af8c82c..589cbdacc5ec 100644
> --- a/block/blk-core.c
> +++ b/block/blk-core.c
> @@ -140,6 +140,7 @@ static const char *const blk_op_name[] = {
>  	REQ_OP_NAME(ZONE_CLOSE),
>  	REQ_OP_NAME(ZONE_FINISH),
>  	REQ_OP_NAME(ZONE_APPEND),
> +	REQ_OP_NAME(ZONE_OFFLINE),
>  	REQ_OP_NAME(WRITE_SAME),
>  	REQ_OP_NAME(WRITE_ZEROES),
>  	REQ_OP_NAME(SCSI_IN),
> @@ -1030,6 +1031,7 @@ generic_make_request_checks(struct bio *bio)
>  	case REQ_OP_ZONE_OPEN:
>  	case REQ_OP_ZONE_CLOSE:
>  	case REQ_OP_ZONE_FINISH:
> +	case REQ_OP_ZONE_OFFLINE:
>  		if (!blk_queue_is_zoned(q))
>  			goto not_supported;
>  		break;
> diff --git a/block/blk-zoned.c b/block/blk-zoned.c
> index 0f156e96e48f..def43ef2b021 100644
> --- a/block/blk-zoned.c
> +++ b/block/blk-zoned.c
> @@ -320,7 +320,8 @@ int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
>  }
>  
>  /*
> - * BLKRESETZONE, BLKOPENZONE, BLKCLOSEZONE and BLKFINISHZONE ioctl processing.
> + * BLKRESETZONE, BLKOPENZONE, BLKCLOSEZONE, BLKFINISHZONE and BLKOFFLINEZONE
> + * ioctl processing.
>   * Called from blkdev_ioctl.
>   */
>  int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
> @@ -363,6 +364,11 @@ int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
>  	case BLKFINISHZONE:
>  		op = REQ_OP_ZONE_FINISH;
>  		break;
> +	case BLKOFFLINEZONE:
> +		if (!(q->zone_flags & BLK_ZONE_SUP_OFFLINE))
> +			return -ENOTTY;
> +		op = REQ_OP_ZONE_OFFLINE;
> +		break;
>  	default:
>  		return -ENOTTY;
>  	}
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index e5f754889234..1f5c7fc3d2c9 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -776,6 +776,9 @@ blk_status_t nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
>  	case REQ_OP_ZONE_FINISH:
>  		ret = nvme_setup_zone_mgmt_send(ns, req, cmd, NVME_ZONE_FINISH);
>  		break;
> +	case REQ_OP_ZONE_OFFLINE:
> +		ret = nvme_setup_zone_mgmt_send(ns, req, cmd, NVME_ZONE_OFFLINE);
> +		break;
>  	case REQ_OP_WRITE_ZEROES:
>  		ret = nvme_setup_write_zeroes(ns, req, cmd);
>  		break;
> diff --git a/drivers/nvme/host/zns.c b/drivers/nvme/host/zns.c
> index afe62dc27ff7..bb6a33f52d53 100644
> --- a/drivers/nvme/host/zns.c
> +++ b/drivers/nvme/host/zns.c
> @@ -81,7 +81,7 @@ int nvme_update_zone_info(struct gendisk *disk, struct nvme_ns *ns,
>  	}
>  
>  	q->limits.zoned = BLK_ZONED_HM;
> -	q->zone_flags = BLK_ZONE_REP_CAPACITY;
> +	q->zone_flags = BLK_ZONE_REP_CAPACITY | BLK_ZONE_SUP_OFFLINE;
>  	blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
>  free_data:
>  	kfree(id);
> diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
> index ccb895f911b1..c0123c643e2f 100644
> --- a/include/linux/blk_types.h
> +++ b/include/linux/blk_types.h
> @@ -316,6 +316,8 @@ enum req_opf {
>  	REQ_OP_ZONE_FINISH	= 12,
>  	/* write data at the current zone write pointer */
>  	REQ_OP_ZONE_APPEND	= 13,
> +	/* Transition a zone to offline */
> +	REQ_OP_ZONE_OFFLINE	= 14,
>  
>  	/* SCSI passthrough using struct scsi_request */
>  	REQ_OP_SCSI_IN		= 32,
> @@ -455,6 +457,7 @@ static inline bool op_is_zone_mgmt(enum req_opf op)
>  	case REQ_OP_ZONE_OPEN:
>  	case REQ_OP_ZONE_CLOSE:
>  	case REQ_OP_ZONE_FINISH:
> +	case REQ_OP_ZONE_OFFLINE:
>  		return true;
>  	default:
>  		return false;
> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> index 3f2e3425fa53..e489b646486d 100644
> --- a/include/linux/blkdev.h
> +++ b/include/linux/blkdev.h
> @@ -370,7 +370,6 @@ extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
>  				     unsigned int cmd, unsigned long arg);
>  extern int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
>  				  unsigned int cmd, unsigned long arg);
> -
>  #else /* CONFIG_BLK_DEV_ZONED */
>  
>  static inline unsigned int blkdev_nr_zones(struct gendisk *disk)
> diff --git a/include/uapi/linux/blkzoned.h b/include/uapi/linux/blkzoned.h
> index 42c3366cc25f..8b7c4705cef7 100644
> --- a/include/uapi/linux/blkzoned.h
> +++ b/include/uapi/linux/blkzoned.h
> @@ -77,9 +77,14 @@ enum blk_zone_cond {
>   * enum blk_zone_report_flags - Feature flags of reported zone descriptors.
>   *
>   * @BLK_ZONE_REP_CAPACITY: Zone descriptor has capacity field.
> + * @BLK_ZONE_SUP_OFFLINE : Zone device supports explicit offline transition.
>   */
>  enum blk_zone_report_flags {
> +	/* Report feature flags */
>  	BLK_ZONE_REP_CAPACITY	= (1 << 0),
> +
> +	/* Supported capabilities */
> +	BLK_ZONE_SUP_OFFLINE	= (1 << 1),
>  };
>  
>  /**
> @@ -166,5 +171,6 @@ struct blk_zone_range {
>  #define BLKOPENZONE	_IOW(0x12, 134, struct blk_zone_range)
>  #define BLKCLOSEZONE	_IOW(0x12, 135, struct blk_zone_range)
>  #define BLKFINISHZONE	_IOW(0x12, 136, struct blk_zone_range)
> +#define BLKOFFLINEZONE	_IOW(0x12, 137, struct blk_zone_range)
>  
>  #endif /* _UAPI_BLKZONED_H */
> 

Device mapper support ?

-- 
Damien Le Moal
Western Digital Research