Commit 659bf827 authored by Niklas Cassel's avatar Niklas Cassel Committed by Jens Axboe
Browse files

block: add max_active_zones to blk-sysfs 



Add a new max_active zones definition in the sysfs documentation.
This definition will be common for all devices utilizing the zoned block
device support in the kernel.

Export max_active_zones according to this new definition for NVMe Zoned
Namespace devices, ZAC ATA devices (which are treated as SCSI devices by
the kernel), and ZBC SCSI devices.

Add the new max_active_zones member to struct request_queue, rather
than as a queue limit, since this property cannot be split across stacking
drivers.

For SCSI devices, even though max active zones is not part of the ZBC/ZAC
spec, export max_active_zones as 0, signifying "no limit".

Signed-off-by: default avatarNiklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: default avatarJavier González <javier@javigon.com>
Reviewed-by: default avatarDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent e15864f8

Documentation/ABI/testing/sysfs-block

+9 −0
Original line number Diff line number Diff line
@@ -273,6 +273,15 @@ Description: 
		device ("host-aware" or "host-managed" zone model). For regular

		block devices, the value is always 0.



What:		/sys/block/<disk>/queue/max_active_zones

Date:		July 2020

Contact:	Niklas Cassel <niklas.cassel@wdc.com>

Description:

		For zoned block devices (zoned attribute indicating

		"host-managed" or "host-aware"), the sum of zones belonging to

		any of the zone states: EXPLICIT OPEN, IMPLICIT OPEN or CLOSED,

		is limited by this value. If this value is 0, there is no limit.



What:		/sys/block/<disk>/queue/max_open_zones

Date:		July 2020

Contact:	Niklas Cassel <niklas.cassel@wdc.com>

Documentation/block/queue-sysfs.rst

+7 −0
Original line number Diff line number Diff line
@@ -117,6 +117,13 @@ Maximum number of elements in a DMA scatter/gather list with integrity 
data that will be submitted by the block layer core to the associated

block driver.



max_active_zones (RO)

---------------------

For zoned block devices (zoned attribute indicating "host-managed" or

"host-aware"), the sum of zones belonging to any of the zone states:

EXPLICIT OPEN, IMPLICIT OPEN or CLOSED, is limited by this value.

If this value is 0, there is no limit.



max_open_zones (RO)

-------------------

For zoned block devices (zoned attribute indicating "host-managed" or

block/blk-sysfs.c

+13 −1
Original line number Diff line number Diff line
@@ -311,6 +311,11 @@ static ssize_t queue_max_open_zones_show(struct request_queue *q, char *page) 
	return queue_var_show(queue_max_open_zones(q), page);

}



static ssize_t queue_max_active_zones_show(struct request_queue *q, char *page)

{

	return queue_var_show(queue_max_active_zones(q), page);

}



static ssize_t queue_nomerges_show(struct request_queue *q, char *page)

{

	return queue_var_show((blk_queue_nomerges(q) << 1) |
@@ -678,6 +683,11 @@ static struct queue_sysfs_entry queue_max_open_zones_entry = { 
	.show = queue_max_open_zones_show,

};



static struct queue_sysfs_entry queue_max_active_zones_entry = {

	.attr = {.name = "max_active_zones", .mode = 0444 },

	.show = queue_max_active_zones_show,

};



static struct queue_sysfs_entry queue_nomerges_entry = {

	.attr = {.name = "nomerges", .mode = 0644 },

	.show = queue_nomerges_show,
@@ -777,6 +787,7 @@ static struct attribute *queue_attrs[] = { 
	&queue_zoned_entry.attr,

	&queue_nr_zones_entry.attr,

	&queue_max_open_zones_entry.attr,

	&queue_max_active_zones_entry.attr,

	&queue_nomerges_entry.attr,

	&queue_rq_affinity_entry.attr,

	&queue_iostats_entry.attr,
@@ -804,7 +815,8 @@ static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr, 
		(!q->mq_ops || !q->mq_ops->timeout))

			return 0;



	if (attr == &queue_max_open_zones_entry.attr &&

	if ((attr == &queue_max_open_zones_entry.attr ||

	     attr == &queue_max_active_zones_entry.attr) &&

	    !blk_queue_is_zoned(q))

		return 0;

drivers/nvme/host/zns.c

+1 −0
Original line number Diff line number Diff line
@@ -97,6 +97,7 @@ int nvme_update_zone_info(struct gendisk *disk, struct nvme_ns *ns, 
	q->limits.zoned = BLK_ZONED_HM;

	blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);

	blk_queue_max_open_zones(q, le32_to_cpu(id->mor) + 1);

	blk_queue_max_active_zones(q, le32_to_cpu(id->mar) + 1);

free_data:

	kfree(id);

	return status;

drivers/scsi/sd_zbc.c

+1 −0
Original line number Diff line number Diff line
@@ -721,6 +721,7 @@ int sd_zbc_read_zones(struct scsi_disk *sdkp, unsigned char *buf) 
		blk_queue_max_open_zones(q, 0);

	else

		blk_queue_max_open_zones(q, sdkp->zones_max_open);

	blk_queue_max_active_zones(q, 0);

	nr_zones = round_up(sdkp->capacity, zone_blocks) >> ilog2(zone_blocks);



	/* READ16/WRITE16 is mandatory for ZBC disks */

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