Commit 7012eef5 authored by Vincent Fu's avatar Vincent Fu Committed by Jens Axboe
Browse files

null_blk: add configfs variables for 2 options 



Allow setting via configfs these two options:

no_sched
shared_tag_bitmap

Previously these could only be activated as module parameters.

Still missing are:

shared_tags
timeout
requeue
init_hctx

Signed-off-by: default avatarVincent Fu <vincent.fu@samsung.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220708174943.87787-3-vincent.fu@samsung.com


[axboe: fold in nullb == NULL fix]
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 058efe00

drivers/block/null_blk/main.c

+48 −19
Original line number Diff line number Diff line
@@ -425,6 +425,8 @@ NULLB_DEVICE_ATTR(zone_nr_conv, uint, NULL); 
NULLB_DEVICE_ATTR(zone_max_open, uint, NULL);

NULLB_DEVICE_ATTR(zone_max_active, uint, NULL);

NULLB_DEVICE_ATTR(virt_boundary, bool, NULL);

NULLB_DEVICE_ATTR(no_sched, bool, NULL);

NULLB_DEVICE_ATTR(shared_tag_bitmap, bool, NULL);



static ssize_t nullb_device_power_show(struct config_item *item, char *page)

{
@@ -548,6 +550,8 @@ static struct configfs_attribute *nullb_device_attrs[] = { 
	&nullb_device_attr_zone_max_open,

	&nullb_device_attr_zone_max_active,

	&nullb_device_attr_virt_boundary,

	&nullb_device_attr_no_sched,

	&nullb_device_attr_shared_tag_bitmap,

	NULL,

};
@@ -604,7 +608,13 @@ nullb_group_drop_item(struct config_group *group, struct config_item *item) 
static ssize_t memb_group_features_show(struct config_item *item, char *page)

{

	return snprintf(page, PAGE_SIZE,

			"memory_backed,discard,bandwidth,cache,badblocks,zoned,zone_size,zone_capacity,zone_nr_conv,zone_max_open,zone_max_active,blocksize,max_sectors,virt_boundary\n");

			"badblocks,blocking,blocksize,cache_size,"

			"completion_nsec,discard,home_node,hw_queue_depth,"

			"irqmode,max_sectors,mbps,memory_backed,no_sched,"

			"poll_queues,power,queue_mode,shared_tag_bitmap,size,"

			"submit_queues,use_per_node_hctx,virt_boundary,zoned,"

			"zone_capacity,zone_max_active,zone_max_open,"

			"zone_nr_conv,zone_size\n");

}



CONFIGFS_ATTR_RO(memb_group_, features);
@@ -678,6 +688,8 @@ static struct nullb_device *null_alloc_dev(void) 
	dev->zone_max_open = g_zone_max_open;

	dev->zone_max_active = g_zone_max_active;

	dev->virt_boundary = g_virt_boundary;

	dev->no_sched = g_no_sched;

	dev->shared_tag_bitmap = g_shared_tag_bitmap;

	return dev;

}
@@ -1885,31 +1897,48 @@ static int null_gendisk_register(struct nullb *nullb) 


static int null_init_tag_set(struct nullb *nullb, struct blk_mq_tag_set *set)

{

	unsigned int flags = BLK_MQ_F_SHOULD_MERGE;

	int hw_queues, numa_node;

	unsigned int queue_depth;

	int poll_queues;



	set->ops = &null_mq_ops;

	set->nr_hw_queues = nullb ? nullb->dev->submit_queues :

						g_submit_queues;

	poll_queues = nullb ? nullb->dev->poll_queues : g_poll_queues;

	if (poll_queues)

		set->nr_hw_queues += poll_queues;

	set->queue_depth = nullb ? nullb->dev->hw_queue_depth :

						g_hw_queue_depth;

	set->numa_node = nullb ? nullb->dev->home_node : g_home_node;

	set->cmd_size	= sizeof(struct nullb_cmd);

	set->flags = BLK_MQ_F_SHOULD_MERGE;

	if (nullb) {

		hw_queues = nullb->dev->submit_queues;

		poll_queues = nullb->dev->poll_queues;

		queue_depth = nullb->dev->hw_queue_depth;

		numa_node = nullb->dev->home_node;

		if (nullb->dev->no_sched)

			flags |= BLK_MQ_F_NO_SCHED;

		if (nullb->dev->shared_tag_bitmap)

			flags |= BLK_MQ_F_TAG_HCTX_SHARED;

		if (nullb->dev->blocking)

			flags |= BLK_MQ_F_BLOCKING;

	} else {

		hw_queues = g_submit_queues;

		poll_queues = g_poll_queues;

		queue_depth = g_hw_queue_depth;

		numa_node = g_home_node;

		if (g_no_sched)

		set->flags |= BLK_MQ_F_NO_SCHED;

			flags |= BLK_MQ_F_NO_SCHED;

		if (g_shared_tag_bitmap)

		set->flags |= BLK_MQ_F_TAG_HCTX_SHARED;

			flags |= BLK_MQ_F_TAG_HCTX_SHARED;

		if (g_blocking)

			flags |= BLK_MQ_F_BLOCKING;

	}



	set->ops = &null_mq_ops;

	set->cmd_size	= sizeof(struct nullb_cmd);

	set->flags = flags;

	set->driver_data = nullb;

	if (poll_queues)

	set->nr_hw_queues = hw_queues;

	set->queue_depth = queue_depth;

	set->numa_node = numa_node;

	if (poll_queues) {

		set->nr_hw_queues += poll_queues;

		set->nr_maps = 3;

	else

	} else {

		set->nr_maps = 1;



	if ((nullb && nullb->dev->blocking) || g_blocking)

		set->flags |= BLK_MQ_F_BLOCKING;

	}



	return blk_mq_alloc_tag_set(set);

}

drivers/block/null_blk/null_blk.h

+2 −0
Original line number Diff line number Diff line
@@ -113,6 +113,8 @@ struct nullb_device { 
	bool discard; /* if support discard */

	bool zoned; /* if device is zoned */

	bool virt_boundary; /* virtual boundary on/off for the device */

	bool no_sched; /* no IO scheduler for the device */

	bool shared_tag_bitmap; /* use hostwide shared tags */

};



struct nullb {