[mirror_ubuntu-artful-kernel.git] / block / blk-sysfs.c

/*
 * Functions related to sysfs handling
 */
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/blktrace_api.h>
#include <linux/blk-mq.h>

#include "blk.h"
#include "blk-cgroup.h"

struct queue_sysfs_entry {
	struct attribute attr;
	ssize_t (*show)(struct request_queue *, char *);
	ssize_t (*store)(struct request_queue *, const char *, size_t);
};

static ssize_t
queue_var_show(unsigned long var, char *page)
{
	return sprintf(page, "%lu\n", var);
}

static ssize_t
queue_var_store(unsigned long *var, const char *page, size_t count)
{
	int err;
	unsigned long v;

	err = kstrtoul(page, 10, &v);
	if (err || v > UINT_MAX)
		return -EINVAL;

	*var = v;

	return count;
}

static ssize_t queue_requests_show(struct request_queue *q, char *page)
{
	return queue_var_show(q->nr_requests, (page));
}

static ssize_t
queue_requests_store(struct request_queue *q, const char *page, size_t count)
{
	struct request_list *rl;
	unsigned long nr;
	int ret;

	if (!q->request_fn)
		return -EINVAL;

	ret = queue_var_store(&nr, page, count);
	if (ret < 0)
		return ret;

	if (nr < BLKDEV_MIN_RQ)
		nr = BLKDEV_MIN_RQ;

	spin_lock_irq(q->queue_lock);
	q->nr_requests = nr;
	blk_queue_congestion_threshold(q);

	/* congestion isn't cgroup aware and follows root blkcg for now */
	rl = &q->root_rl;

	if (rl->count[BLK_RW_SYNC] >= queue_congestion_on_threshold(q))
		blk_set_queue_congested(q, BLK_RW_SYNC);
	else if (rl->count[BLK_RW_SYNC] < queue_congestion_off_threshold(q))
		blk_clear_queue_congested(q, BLK_RW_SYNC);

	if (rl->count[BLK_RW_ASYNC] >= queue_congestion_on_threshold(q))
		blk_set_queue_congested(q, BLK_RW_ASYNC);
	else if (rl->count[BLK_RW_ASYNC] < queue_congestion_off_threshold(q))
		blk_clear_queue_congested(q, BLK_RW_ASYNC);

	blk_queue_for_each_rl(rl, q) {
		if (rl->count[BLK_RW_SYNC] >= q->nr_requests) {
			blk_set_rl_full(rl, BLK_RW_SYNC);
		} else {
			blk_clear_rl_full(rl, BLK_RW_SYNC);
			wake_up(&rl->wait[BLK_RW_SYNC]);
		}

		if (rl->count[BLK_RW_ASYNC] >= q->nr_requests) {
			blk_set_rl_full(rl, BLK_RW_ASYNC);
		} else {
			blk_clear_rl_full(rl, BLK_RW_ASYNC);
			wake_up(&rl->wait[BLK_RW_ASYNC]);
		}
	}

	spin_unlock_irq(q->queue_lock);
	return ret;
}

static ssize_t queue_ra_show(struct request_queue *q, char *page)
{
	unsigned long ra_kb = q->backing_dev_info.ra_pages <<
					(PAGE_CACHE_SHIFT - 10);

	return queue_var_show(ra_kb, (page));
}

static ssize_t
queue_ra_store(struct request_queue *q, const char *page, size_t count)
{
	unsigned long ra_kb;
	ssize_t ret = queue_var_store(&ra_kb, page, count);

	if (ret < 0)
		return ret;

	q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);

	return ret;
}

static ssize_t queue_max_sectors_show(struct request_queue *q, char *page)
{
	int max_sectors_kb = queue_max_sectors(q) >> 1;

	return queue_var_show(max_sectors_kb, (page));
}

static ssize_t queue_max_segments_show(struct request_queue *q, char *page)
{
	return queue_var_show(queue_max_segments(q), (page));
}

static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page)
{
	return queue_var_show(q->limits.max_integrity_segments, (page));
}

static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page)
{
	if (blk_queue_cluster(q))
		return queue_var_show(queue_max_segment_size(q), (page));

	return queue_var_show(PAGE_CACHE_SIZE, (page));
}

static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page)
{
	return queue_var_show(queue_logical_block_size(q), page);
}

static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page)
{
	return queue_var_show(queue_physical_block_size(q), page);
}

static ssize_t queue_io_min_show(struct request_queue *q, char *page)
{
	return queue_var_show(queue_io_min(q), page);
}

static ssize_t queue_io_opt_show(struct request_queue *q, char *page)
{
	return queue_var_show(queue_io_opt(q), page);
}

static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page)
{
	return queue_var_show(q->limits.discard_granularity, page);
}

static ssize_t queue_discard_max_show(struct request_queue *q, char *page)
{
	return sprintf(page, "%llu\n",
		       (unsigned long long)q->limits.max_discard_sectors << 9);
}

static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page)
{
	return queue_var_show(queue_discard_zeroes_data(q), page);
}

static ssize_t queue_write_same_max_show(struct request_queue *q, char *page)
{
	return sprintf(page, "%llu\n",
		(unsigned long long)q->limits.max_write_same_sectors << 9);
}


static ssize_t
queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
{
	unsigned long max_sectors_kb,
		max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
			page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
	ssize_t ret = queue_var_store(&max_sectors_kb, page, count);

	if (ret < 0)
		return ret;

	if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb)
		return -EINVAL;

	spin_lock_irq(q->queue_lock);
	q->limits.max_sectors = max_sectors_kb << 1;
	spin_unlock_irq(q->queue_lock);

	return ret;
}

static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page)
{
	int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;

	return queue_var_show(max_hw_sectors_kb, (page));
}

#define QUEUE_SYSFS_BIT_FNS(name, flag, neg)				\
static ssize_t								\
queue_show_##name(struct request_queue *q, char *page)			\
{									\
	int bit;							\
	bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags);		\
	return queue_var_show(neg ? !bit : bit, page);			\
}									\
static ssize_t								\
queue_store_##name(struct request_queue *q, const char *page, size_t count) \
{									\
	unsigned long val;						\
	ssize_t ret;							\
	ret = queue_var_store(&val, page, count);			\
	if (ret < 0)							\
		 return ret;						\
	if (neg)							\
		val = !val;						\
									\
	spin_lock_irq(q->queue_lock);					\
	if (val)							\
		queue_flag_set(QUEUE_FLAG_##flag, q);			\
	else								\
		queue_flag_clear(QUEUE_FLAG_##flag, q);			\
	spin_unlock_irq(q->queue_lock);					\
	return ret;							\
}

QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
#undef QUEUE_SYSFS_BIT_FNS

static ssize_t queue_nomerges_show(struct request_queue *q, char *page)
{
	return queue_var_show((blk_queue_nomerges(q) << 1) |
			       blk_queue_noxmerges(q), page);
}

static ssize_t queue_nomerges_store(struct request_queue *q, const char *page,
				    size_t count)
{
	unsigned long nm;
	ssize_t ret = queue_var_store(&nm, page, count);

	if (ret < 0)
		return ret;

	spin_lock_irq(q->queue_lock);
	queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
	queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
	if (nm == 2)
		queue_flag_set(QUEUE_FLAG_NOMERGES, q);
	else if (nm)
		queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
	spin_unlock_irq(q->queue_lock);

	return ret;
}

static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page)
{
	bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
	bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags);

	return queue_var_show(set << force, page);
}

static ssize_t
queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
{
	ssize_t ret = -EINVAL;
#ifdef CONFIG_SMP
	unsigned long val;

	ret = queue_var_store(&val, page, count);
	if (ret < 0)
		return ret;

	spin_lock_irq(q->queue_lock);
	if (val == 2) {
		queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
		queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
	} else if (val == 1) {
		queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
		queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
	} else if (val == 0) {
		queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
		queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
	}
	spin_unlock_irq(q->queue_lock);
#endif
	return ret;
}

static struct queue_sysfs_entry queue_requests_entry = {
	.attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR },
	.show = queue_requests_show,
	.store = queue_requests_store,
};

static struct queue_sysfs_entry queue_ra_entry = {
	.attr = {.name = "read_ahead_kb", .mode = S_IRUGO | S_IWUSR },
	.show = queue_ra_show,
	.store = queue_ra_store,
};

static struct queue_sysfs_entry queue_max_sectors_entry = {
	.attr = {.name = "max_sectors_kb", .mode = S_IRUGO | S_IWUSR },
	.show = queue_max_sectors_show,
	.store = queue_max_sectors_store,
};

static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
	.attr = {.name = "max_hw_sectors_kb", .mode = S_IRUGO },
	.show = queue_max_hw_sectors_show,
};

static struct queue_sysfs_entry queue_max_segments_entry = {
	.attr = {.name = "max_segments", .mode = S_IRUGO },
	.show = queue_max_segments_show,
};

static struct queue_sysfs_entry queue_max_integrity_segments_entry = {
	.attr = {.name = "max_integrity_segments", .mode = S_IRUGO },
	.show = queue_max_integrity_segments_show,
};

static struct queue_sysfs_entry queue_max_segment_size_entry = {
	.attr = {.name = "max_segment_size", .mode = S_IRUGO },
	.show = queue_max_segment_size_show,
};

static struct queue_sysfs_entry queue_iosched_entry = {
	.attr = {.name = "scheduler", .mode = S_IRUGO | S_IWUSR },
	.show = elv_iosched_show,
	.store = elv_iosched_store,
};

static struct queue_sysfs_entry queue_hw_sector_size_entry = {
	.attr = {.name = "hw_sector_size", .mode = S_IRUGO },
	.show = queue_logical_block_size_show,
};

static struct queue_sysfs_entry queue_logical_block_size_entry = {
	.attr = {.name = "logical_block_size", .mode = S_IRUGO },
	.show = queue_logical_block_size_show,
};

static struct queue_sysfs_entry queue_physical_block_size_entry = {
	.attr = {.name = "physical_block_size", .mode = S_IRUGO },
	.show = queue_physical_block_size_show,
};

static struct queue_sysfs_entry queue_io_min_entry = {
	.attr = {.name = "minimum_io_size", .mode = S_IRUGO },
	.show = queue_io_min_show,
};

static struct queue_sysfs_entry queue_io_opt_entry = {
	.attr = {.name = "optimal_io_size", .mode = S_IRUGO },
	.show = queue_io_opt_show,
};

static struct queue_sysfs_entry queue_discard_granularity_entry = {
	.attr = {.name = "discard_granularity", .mode = S_IRUGO },
	.show = queue_discard_granularity_show,
};

static struct queue_sysfs_entry queue_discard_max_entry = {
	.attr = {.name = "discard_max_bytes", .mode = S_IRUGO },
	.show = queue_discard_max_show,
};

static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
	.attr = {.name = "discard_zeroes_data", .mode = S_IRUGO },
	.show = queue_discard_zeroes_data_show,
};

static struct queue_sysfs_entry queue_write_same_max_entry = {
	.attr = {.name = "write_same_max_bytes", .mode = S_IRUGO },
	.show = queue_write_same_max_show,
};

static struct queue_sysfs_entry queue_nonrot_entry = {
	.attr = {.name = "rotational", .mode = S_IRUGO | S_IWUSR },
	.show = queue_show_nonrot,
	.store = queue_store_nonrot,
};

static struct queue_sysfs_entry queue_nomerges_entry = {
	.attr = {.name = "nomerges", .mode = S_IRUGO | S_IWUSR },
	.show = queue_nomerges_show,
	.store = queue_nomerges_store,
};

static struct queue_sysfs_entry queue_rq_affinity_entry = {
	.attr = {.name = "rq_affinity", .mode = S_IRUGO | S_IWUSR },
	.show = queue_rq_affinity_show,
	.store = queue_rq_affinity_store,
};

static struct queue_sysfs_entry queue_iostats_entry = {
	.attr = {.name = "iostats", .mode = S_IRUGO | S_IWUSR },
	.show = queue_show_iostats,
	.store = queue_store_iostats,
};

static struct queue_sysfs_entry queue_random_entry = {
	.attr = {.name = "add_random", .mode = S_IRUGO | S_IWUSR },
	.show = queue_show_random,
	.store = queue_store_random,
};

static struct attribute *default_attrs[] = {
	&queue_requests_entry.attr,
	&queue_ra_entry.attr,
	&queue_max_hw_sectors_entry.attr,
	&queue_max_sectors_entry.attr,
	&queue_max_segments_entry.attr,
	&queue_max_integrity_segments_entry.attr,
	&queue_max_segment_size_entry.attr,
	&queue_iosched_entry.attr,
	&queue_hw_sector_size_entry.attr,
	&queue_logical_block_size_entry.attr,
	&queue_physical_block_size_entry.attr,
	&queue_io_min_entry.attr,
	&queue_io_opt_entry.attr,
	&queue_discard_granularity_entry.attr,
	&queue_discard_max_entry.attr,
	&queue_discard_zeroes_data_entry.attr,
	&queue_write_same_max_entry.attr,
	&queue_nonrot_entry.attr,
	&queue_nomerges_entry.attr,
	&queue_rq_affinity_entry.attr,
	&queue_iostats_entry.attr,
	&queue_random_entry.attr,
	NULL,
};

#define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)

static ssize_t
queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
{
	struct queue_sysfs_entry *entry = to_queue(attr);
	struct request_queue *q =
		container_of(kobj, struct request_queue, kobj);
	ssize_t res;

	if (!entry->show)
		return -EIO;
	mutex_lock(&q->sysfs_lock);
	if (blk_queue_dying(q)) {
		mutex_unlock(&q->sysfs_lock);
		return -ENOENT;
	}
	res = entry->show(q, page);
	mutex_unlock(&q->sysfs_lock);
	return res;
}

static ssize_t
queue_attr_store(struct kobject *kobj, struct attribute *attr,
		    const char *page, size_t length)
{
	struct queue_sysfs_entry *entry = to_queue(attr);
	struct request_queue *q;
	ssize_t res;

	if (!entry->store)
		return -EIO;

	q = container_of(kobj, struct request_queue, kobj);
	mutex_lock(&q->sysfs_lock);
	if (blk_queue_dying(q)) {
		mutex_unlock(&q->sysfs_lock);
		return -ENOENT;
	}
	res = entry->store(q, page, length);
	mutex_unlock(&q->sysfs_lock);
	return res;
}

static void blk_free_queue_rcu(struct rcu_head *rcu_head)
{
	struct request_queue *q = container_of(rcu_head, struct request_queue,
					       rcu_head);
	kmem_cache_free(blk_requestq_cachep, q);
}

/**
 * blk_release_queue: - release a &struct request_queue when it is no longer needed
 * @kobj:    the kobj belonging to the request queue to be released
 *
 * Description:
 *     blk_release_queue is the pair to blk_init_queue() or
 *     blk_queue_make_request().  It should be called when a request queue is
 *     being released; typically when a block device is being de-registered.
 *     Currently, its primary task it to free all the &struct request
 *     structures that were allocated to the queue and the queue itself.
 *
 * Caveat:
 *     Hopefully the low level driver will have finished any
 *     outstanding requests first...
 **/
static void blk_release_queue(struct kobject *kobj)
{
	struct request_queue *q =
		container_of(kobj, struct request_queue, kobj);

	blk_sync_queue(q);

	blkcg_exit_queue(q);

	if (q->elevator) {
		spin_lock_irq(q->queue_lock);
		ioc_clear_queue(q);
		spin_unlock_irq(q->queue_lock);
		elevator_exit(q->elevator);
	}

	blk_exit_rl(&q->root_rl);

	if (q->queue_tags)
		__blk_queue_free_tags(q);

	percpu_counter_destroy(&q->mq_usage_counter);

	if (q->mq_ops)
		blk_mq_free_queue(q);

	blk_trace_shutdown(q);

	bdi_destroy(&q->backing_dev_info);

	ida_simple_remove(&blk_queue_ida, q->id);
	call_rcu(&q->rcu_head, blk_free_queue_rcu);
}

static const struct sysfs_ops queue_sysfs_ops = {
	.show	= queue_attr_show,
	.store	= queue_attr_store,
};

struct kobj_type blk_queue_ktype = {
	.sysfs_ops	= &queue_sysfs_ops,
	.default_attrs	= default_attrs,
	.release	= blk_release_queue,
};

int blk_register_queue(struct gendisk *disk)
{
	int ret;
	struct device *dev = disk_to_dev(disk);
	struct request_queue *q = disk->queue;

	if (WARN_ON(!q))
		return -ENXIO;

	/*
	 * Initialization must be complete by now.  Finish the initial
	 * bypass from queue allocation.
	 */
	blk_queue_bypass_end(q);
	queue_flag_set_unlocked(QUEUE_FLAG_INIT_DONE, q);

	ret = blk_trace_init_sysfs(dev);
	if (ret)
		return ret;

	ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
	if (ret < 0) {
		blk_trace_remove_sysfs(dev);
		return ret;
	}

	kobject_uevent(&q->kobj, KOBJ_ADD);

	if (q->mq_ops)
		blk_mq_register_disk(disk);

	if (!q->request_fn)
		return 0;

	ret = elv_register_queue(q);
	if (ret) {
		kobject_uevent(&q->kobj, KOBJ_REMOVE);
		kobject_del(&q->kobj);
		blk_trace_remove_sysfs(dev);
		kobject_put(&dev->kobj);
		return ret;
	}

	return 0;
}

void blk_unregister_queue(struct gendisk *disk)
{
	struct request_queue *q = disk->queue;

	if (WARN_ON(!q))
		return;

	if (q->mq_ops)
		blk_mq_unregister_disk(disk);

	if (q->request_fn)
		elv_unregister_queue(q);

	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	kobject_del(&q->kobj);
	blk_trace_remove_sysfs(disk_to_dev(disk));
	kobject_put(&disk_to_dev(disk)->kobj);
}
Commit	Line	Data
8324aa91 JA	1	/*
	2	* Functions related to sysfs handling
	3	*/
	4	#include <linux/kernel.h>
5a0e3ad6	5	#include <linux/slab.h>
8324aa91 JA	6	#include <linux/module.h>
	7	#include <linux/bio.h>
	8	#include <linux/blkdev.h>
	9	#include <linux/blktrace_api.h>
320ae51f	10	#include <linux/blk-mq.h>
8324aa91 JA	11
8324aa91 JA	12	#include "blk.h"
5efd6113	13	#include "blk-cgroup.h"
8324aa91 JA	14
	15	struct queue_sysfs_entry {
	16	struct attribute attr;
	17	ssize_t (show)(struct request_queue , char *);
	18	ssize_t (store)(struct request_queue , const char *, size_t);
	19	};
	20
	21	static ssize_t
9cb308ce	22	queue_var_show(unsigned long var, char *page)
8324aa91	23	{
9cb308ce	24	return sprintf(page, "%lu\n", var);
8324aa91 JA	25	}
	26
	27	static ssize_t
	28	queue_var_store(unsigned long var, const char page, size_t count)
	29	{
b1f3b64d DR	30	int err;
	31	unsigned long v;
	32
ed751e68	33	err = kstrtoul(page, 10, &v);
b1f3b64d DR	34	if (err \|\| v > UINT_MAX)
	35	return -EINVAL;
	36
	37	*var = v;
8324aa91	38
8324aa91 JA	39	return count;
	40	}
	41
	42	static ssize_t queue_requests_show(struct request_queue q, char page)
	43	{
	44	return queue_var_show(q->nr_requests, (page));
	45	}
	46
	47	static ssize_t
	48	queue_requests_store(struct request_queue q, const char page, size_t count)
	49	{
a051661c	50	struct request_list *rl;
8324aa91	51	unsigned long nr;
b8a9ae77 JA	52	int ret;
	53
	54	if (!q->request_fn)
	55	return -EINVAL;
	56
	57	ret = queue_var_store(&nr, page, count);
b1f3b64d DR	58	if (ret < 0)
	59	return ret;
	60
8324aa91 JA	61	if (nr < BLKDEV_MIN_RQ)
	62	nr = BLKDEV_MIN_RQ;
	63
	64	spin_lock_irq(q->queue_lock);
	65	q->nr_requests = nr;
	66	blk_queue_congestion_threshold(q);
	67
a051661c TH	68	/* congestion isn't cgroup aware and follows root blkcg for now */
	69	rl = &q->root_rl;
	70
1faa16d2 JA	71	if (rl->count[BLK_RW_SYNC] >= queue_congestion_on_threshold(q))
	72	blk_set_queue_congested(q, BLK_RW_SYNC);
	73	else if (rl->count[BLK_RW_SYNC] < queue_congestion_off_threshold(q))
	74	blk_clear_queue_congested(q, BLK_RW_SYNC);
	75
	76	if (rl->count[BLK_RW_ASYNC] >= queue_congestion_on_threshold(q))
	77	blk_set_queue_congested(q, BLK_RW_ASYNC);
	78	else if (rl->count[BLK_RW_ASYNC] < queue_congestion_off_threshold(q))
	79	blk_clear_queue_congested(q, BLK_RW_ASYNC);
	80
a051661c TH	81	blk_queue_for_each_rl(rl, q) {
	82	if (rl->count[BLK_RW_SYNC] >= q->nr_requests) {
	83	blk_set_rl_full(rl, BLK_RW_SYNC);
	84	} else {
	85	blk_clear_rl_full(rl, BLK_RW_SYNC);
	86	wake_up(&rl->wait[BLK_RW_SYNC]);
	87	}
	88
	89	if (rl->count[BLK_RW_ASYNC] >= q->nr_requests) {
	90	blk_set_rl_full(rl, BLK_RW_ASYNC);
	91	} else {
	92	blk_clear_rl_full(rl, BLK_RW_ASYNC);
	93	wake_up(&rl->wait[BLK_RW_ASYNC]);
	94	}
8324aa91 JA	95	}
8324aa91 JA	96
8324aa91 JA	97	spin_unlock_irq(q->queue_lock);
	98	return ret;
	99	}
	100
	101	static ssize_t queue_ra_show(struct request_queue q, char page)
	102	{
9cb308ce XF	103	unsigned long ra_kb = q->backing_dev_info.ra_pages <<
9cb308ce XF	104	(PAGE_CACHE_SHIFT - 10);
8324aa91 JA	105
	106	return queue_var_show(ra_kb, (page));
	107	}
	108
	109	static ssize_t
	110	queue_ra_store(struct request_queue q, const char page, size_t count)
	111	{
	112	unsigned long ra_kb;
	113	ssize_t ret = queue_var_store(&ra_kb, page, count);
	114
b1f3b64d DR	115	if (ret < 0)
	116	return ret;
	117
8324aa91	118	q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);
8324aa91 JA	119
	120	return ret;
	121	}
	122
	123	static ssize_t queue_max_sectors_show(struct request_queue q, char page)
	124	{
ae03bf63	125	int max_sectors_kb = queue_max_sectors(q) >> 1;
8324aa91 JA	126
	127	return queue_var_show(max_sectors_kb, (page));
	128	}
	129
c77a5710 MP	130	static ssize_t queue_max_segments_show(struct request_queue q, char page)
	131	{
	132	return queue_var_show(queue_max_segments(q), (page));
	133	}
	134
13f05c8d MP	135	static ssize_t queue_max_integrity_segments_show(struct request_queue q, char page)
	136	{
	137	return queue_var_show(q->limits.max_integrity_segments, (page));
	138	}
	139
c77a5710 MP	140	static ssize_t queue_max_segment_size_show(struct request_queue q, char page)
c77a5710 MP	141	{
e692cb66	142	if (blk_queue_cluster(q))
c77a5710 MP	143	return queue_var_show(queue_max_segment_size(q), (page));
	144
	145	return queue_var_show(PAGE_CACHE_SIZE, (page));
	146	}
	147
e1defc4f	148	static ssize_t queue_logical_block_size_show(struct request_queue q, char page)
e68b903c	149	{
e1defc4f	150	return queue_var_show(queue_logical_block_size(q), page);
e68b903c MP	151	}
e68b903c MP	152
c72758f3 MP	153	static ssize_t queue_physical_block_size_show(struct request_queue q, char page)
	154	{
	155	return queue_var_show(queue_physical_block_size(q), page);
	156	}
	157
	158	static ssize_t queue_io_min_show(struct request_queue q, char page)
	159	{
	160	return queue_var_show(queue_io_min(q), page);
	161	}
	162
	163	static ssize_t queue_io_opt_show(struct request_queue q, char page)
	164	{
	165	return queue_var_show(queue_io_opt(q), page);
e68b903c MP	166	}
e68b903c MP	167
86b37281 MP	168	static ssize_t queue_discard_granularity_show(struct request_queue q, char page)
	169	{
	170	return queue_var_show(q->limits.discard_granularity, page);
	171	}
	172
	173	static ssize_t queue_discard_max_show(struct request_queue q, char page)
	174	{
a934a00a MP	175	return sprintf(page, "%llu\n",
a934a00a MP	176	(unsigned long long)q->limits.max_discard_sectors << 9);
86b37281 MP	177	}
86b37281 MP	178
98262f27 MP	179	static ssize_t queue_discard_zeroes_data_show(struct request_queue q, char page)
	180	{
	181	return queue_var_show(queue_discard_zeroes_data(q), page);
	182	}
	183
4363ac7c MP	184	static ssize_t queue_write_same_max_show(struct request_queue q, char page)
	185	{
	186	return sprintf(page, "%llu\n",
	187	(unsigned long long)q->limits.max_write_same_sectors << 9);
	188	}
	189
	190
8324aa91 JA	191	static ssize_t
	192	queue_max_sectors_store(struct request_queue q, const char page, size_t count)
	193	{
	194	unsigned long max_sectors_kb,
ae03bf63	195	max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
8324aa91 JA	196	page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
	197	ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
	198
b1f3b64d DR	199	if (ret < 0)
	200	return ret;
	201
8324aa91 JA	202	if (max_sectors_kb > max_hw_sectors_kb \|\| max_sectors_kb < page_kb)
8324aa91 JA	203	return -EINVAL;
7c239517	204
8324aa91	205	spin_lock_irq(q->queue_lock);
c295fc05	206	q->limits.max_sectors = max_sectors_kb << 1;
8324aa91 JA	207	spin_unlock_irq(q->queue_lock);
	208
	209	return ret;
	210	}
	211
	212	static ssize_t queue_max_hw_sectors_show(struct request_queue q, char page)
	213	{
ae03bf63	214	int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
8324aa91 JA	215
	216	return queue_var_show(max_hw_sectors_kb, (page));
	217	}
	218
956bcb7c JA	219	#define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \
	220	static ssize_t \
	221	queue_show_##name(struct request_queue q, char page) \
	222	{ \
	223	int bit; \
	224	bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \
	225	return queue_var_show(neg ? !bit : bit, page); \
	226	} \
	227	static ssize_t \
	228	queue_store_##name(struct request_queue q, const char page, size_t count) \
	229	{ \
	230	unsigned long val; \
	231	ssize_t ret; \
	232	ret = queue_var_store(&val, page, count); \
c678ef52 AB	233	if (ret < 0) \
c678ef52 AB	234	return ret; \
956bcb7c JA	235	if (neg) \
	236	val = !val; \
	237	\
	238	spin_lock_irq(q->queue_lock); \
	239	if (val) \
	240	queue_flag_set(QUEUE_FLAG_##flag, q); \
	241	else \
	242	queue_flag_clear(QUEUE_FLAG_##flag, q); \
	243	spin_unlock_irq(q->queue_lock); \
	244	return ret; \
1308835f BZ	245	}
1308835f BZ	246
956bcb7c JA	247	QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
	248	QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
	249	QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
	250	#undef QUEUE_SYSFS_BIT_FNS
1308835f	251
ac9fafa1 AB	252	static ssize_t queue_nomerges_show(struct request_queue q, char page)
ac9fafa1 AB	253	{
488991e2 AB	254	return queue_var_show((blk_queue_nomerges(q) << 1) \|
488991e2 AB	255	blk_queue_noxmerges(q), page);
ac9fafa1 AB	256	}
	257
	258	static ssize_t queue_nomerges_store(struct request_queue q, const char page,
	259	size_t count)
	260	{
	261	unsigned long nm;
	262	ssize_t ret = queue_var_store(&nm, page, count);
	263
b1f3b64d DR	264	if (ret < 0)
	265	return ret;
	266
bf0f9702	267	spin_lock_irq(q->queue_lock);
488991e2 AB	268	queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
	269	queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
	270	if (nm == 2)
bf0f9702	271	queue_flag_set(QUEUE_FLAG_NOMERGES, q);
488991e2 AB	272	else if (nm)
488991e2 AB	273	queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
bf0f9702	274	spin_unlock_irq(q->queue_lock);
1308835f	275
ac9fafa1 AB	276	return ret;
	277	}
	278
c7c22e4d JA	279	static ssize_t queue_rq_affinity_show(struct request_queue q, char page)
c7c22e4d JA	280	{
9cb308ce	281	bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
5757a6d7	282	bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags);
c7c22e4d	283
5757a6d7	284	return queue_var_show(set << force, page);
c7c22e4d JA	285	}
	286
	287	static ssize_t
	288	queue_rq_affinity_store(struct request_queue q, const char page, size_t count)
	289	{
	290	ssize_t ret = -EINVAL;
0a06ff06	291	#ifdef CONFIG_SMP
c7c22e4d JA	292	unsigned long val;
	293
	294	ret = queue_var_store(&val, page, count);
b1f3b64d DR	295	if (ret < 0)
	296	return ret;
	297
c7c22e4d	298	spin_lock_irq(q->queue_lock);
e8037d49	299	if (val == 2) {
c7c22e4d	300	queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
e8037d49 ES	301	queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
	302	} else if (val == 1) {
	303	queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
	304	queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
	305	} else if (val == 0) {
5757a6d7 DW	306	queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
	307	queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
	308	}
c7c22e4d JA	309	spin_unlock_irq(q->queue_lock);
	310	#endif
	311	return ret;
	312	}
8324aa91 JA	313
	314	static struct queue_sysfs_entry queue_requests_entry = {
	315	.attr = {.name = "nr_requests", .mode = S_IRUGO \| S_IWUSR },
	316	.show = queue_requests_show,
	317	.store = queue_requests_store,
	318	};
	319
	320	static struct queue_sysfs_entry queue_ra_entry = {
	321	.attr = {.name = "read_ahead_kb", .mode = S_IRUGO \| S_IWUSR },
	322	.show = queue_ra_show,
	323	.store = queue_ra_store,
	324	};
	325
	326	static struct queue_sysfs_entry queue_max_sectors_entry = {
	327	.attr = {.name = "max_sectors_kb", .mode = S_IRUGO \| S_IWUSR },
	328	.show = queue_max_sectors_show,
	329	.store = queue_max_sectors_store,
	330	};
	331
	332	static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
	333	.attr = {.name = "max_hw_sectors_kb", .mode = S_IRUGO },
	334	.show = queue_max_hw_sectors_show,
	335	};
	336
c77a5710 MP	337	static struct queue_sysfs_entry queue_max_segments_entry = {
	338	.attr = {.name = "max_segments", .mode = S_IRUGO },
	339	.show = queue_max_segments_show,
	340	};
	341
13f05c8d MP	342	static struct queue_sysfs_entry queue_max_integrity_segments_entry = {
	343	.attr = {.name = "max_integrity_segments", .mode = S_IRUGO },
	344	.show = queue_max_integrity_segments_show,
	345	};
	346
c77a5710 MP	347	static struct queue_sysfs_entry queue_max_segment_size_entry = {
	348	.attr = {.name = "max_segment_size", .mode = S_IRUGO },
	349	.show = queue_max_segment_size_show,
	350	};
	351
8324aa91 JA	352	static struct queue_sysfs_entry queue_iosched_entry = {
	353	.attr = {.name = "scheduler", .mode = S_IRUGO \| S_IWUSR },
	354	.show = elv_iosched_show,
	355	.store = elv_iosched_store,
	356	};
	357
e68b903c MP	358	static struct queue_sysfs_entry queue_hw_sector_size_entry = {
e68b903c MP	359	.attr = {.name = "hw_sector_size", .mode = S_IRUGO },
e1defc4f MP	360	.show = queue_logical_block_size_show,
	361	};
	362
	363	static struct queue_sysfs_entry queue_logical_block_size_entry = {
	364	.attr = {.name = "logical_block_size", .mode = S_IRUGO },
	365	.show = queue_logical_block_size_show,
e68b903c MP	366	};
e68b903c MP	367
c72758f3 MP	368	static struct queue_sysfs_entry queue_physical_block_size_entry = {
	369	.attr = {.name = "physical_block_size", .mode = S_IRUGO },
	370	.show = queue_physical_block_size_show,
	371	};
	372
	373	static struct queue_sysfs_entry queue_io_min_entry = {
	374	.attr = {.name = "minimum_io_size", .mode = S_IRUGO },
	375	.show = queue_io_min_show,
	376	};
	377
	378	static struct queue_sysfs_entry queue_io_opt_entry = {
	379	.attr = {.name = "optimal_io_size", .mode = S_IRUGO },
	380	.show = queue_io_opt_show,
e68b903c MP	381	};
e68b903c MP	382
86b37281 MP	383	static struct queue_sysfs_entry queue_discard_granularity_entry = {
	384	.attr = {.name = "discard_granularity", .mode = S_IRUGO },
	385	.show = queue_discard_granularity_show,
	386	};
	387
	388	static struct queue_sysfs_entry queue_discard_max_entry = {
	389	.attr = {.name = "discard_max_bytes", .mode = S_IRUGO },
	390	.show = queue_discard_max_show,
	391	};
	392
98262f27 MP	393	static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
	394	.attr = {.name = "discard_zeroes_data", .mode = S_IRUGO },
	395	.show = queue_discard_zeroes_data_show,
	396	};
	397
4363ac7c MP	398	static struct queue_sysfs_entry queue_write_same_max_entry = {
	399	.attr = {.name = "write_same_max_bytes", .mode = S_IRUGO },
	400	.show = queue_write_same_max_show,
	401	};
	402
1308835f BZ	403	static struct queue_sysfs_entry queue_nonrot_entry = {
1308835f BZ	404	.attr = {.name = "rotational", .mode = S_IRUGO \| S_IWUSR },
956bcb7c JA	405	.show = queue_show_nonrot,
956bcb7c JA	406	.store = queue_store_nonrot,
1308835f BZ	407	};
1308835f BZ	408
ac9fafa1 AB	409	static struct queue_sysfs_entry queue_nomerges_entry = {
	410	.attr = {.name = "nomerges", .mode = S_IRUGO \| S_IWUSR },
	411	.show = queue_nomerges_show,
	412	.store = queue_nomerges_store,
	413	};
	414
c7c22e4d JA	415	static struct queue_sysfs_entry queue_rq_affinity_entry = {
	416	.attr = {.name = "rq_affinity", .mode = S_IRUGO \| S_IWUSR },
	417	.show = queue_rq_affinity_show,
	418	.store = queue_rq_affinity_store,
	419	};
	420
bc58ba94 JA	421	static struct queue_sysfs_entry queue_iostats_entry = {
bc58ba94 JA	422	.attr = {.name = "iostats", .mode = S_IRUGO \| S_IWUSR },
956bcb7c JA	423	.show = queue_show_iostats,
956bcb7c JA	424	.store = queue_store_iostats,
bc58ba94 JA	425	};
bc58ba94 JA	426
e2e1a148 JA	427	static struct queue_sysfs_entry queue_random_entry = {
e2e1a148 JA	428	.attr = {.name = "add_random", .mode = S_IRUGO \| S_IWUSR },
956bcb7c JA	429	.show = queue_show_random,
956bcb7c JA	430	.store = queue_store_random,
e2e1a148 JA	431	};
e2e1a148 JA	432
8324aa91 JA	433	static struct attribute *default_attrs[] = {
	434	&queue_requests_entry.attr,
	435	&queue_ra_entry.attr,
	436	&queue_max_hw_sectors_entry.attr,
	437	&queue_max_sectors_entry.attr,
c77a5710	438	&queue_max_segments_entry.attr,
13f05c8d	439	&queue_max_integrity_segments_entry.attr,
c77a5710	440	&queue_max_segment_size_entry.attr,
8324aa91	441	&queue_iosched_entry.attr,
e68b903c	442	&queue_hw_sector_size_entry.attr,
e1defc4f	443	&queue_logical_block_size_entry.attr,
c72758f3 MP	444	&queue_physical_block_size_entry.attr,
	445	&queue_io_min_entry.attr,
	446	&queue_io_opt_entry.attr,
86b37281 MP	447	&queue_discard_granularity_entry.attr,
86b37281 MP	448	&queue_discard_max_entry.attr,
98262f27	449	&queue_discard_zeroes_data_entry.attr,
4363ac7c	450	&queue_write_same_max_entry.attr,
1308835f	451	&queue_nonrot_entry.attr,
ac9fafa1	452	&queue_nomerges_entry.attr,
c7c22e4d	453	&queue_rq_affinity_entry.attr,
bc58ba94	454	&queue_iostats_entry.attr,
e2e1a148	455	&queue_random_entry.attr,
8324aa91 JA	456	NULL,
	457	};
	458
	459	#define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
	460
	461	static ssize_t
	462	queue_attr_show(struct kobject kobj, struct attribute attr, char *page)
	463	{
	464	struct queue_sysfs_entry *entry = to_queue(attr);
	465	struct request_queue *q =
	466	container_of(kobj, struct request_queue, kobj);
	467	ssize_t res;
	468
	469	if (!entry->show)
	470	return -EIO;
	471	mutex_lock(&q->sysfs_lock);
3f3299d5	472	if (blk_queue_dying(q)) {
8324aa91 JA	473	mutex_unlock(&q->sysfs_lock);
	474	return -ENOENT;
	475	}
	476	res = entry->show(q, page);
	477	mutex_unlock(&q->sysfs_lock);
	478	return res;
	479	}
	480
	481	static ssize_t
	482	queue_attr_store(struct kobject kobj, struct attribute attr,
	483	const char *page, size_t length)
	484	{
	485	struct queue_sysfs_entry *entry = to_queue(attr);
6728cb0e	486	struct request_queue *q;
8324aa91 JA	487	ssize_t res;
	488
	489	if (!entry->store)
	490	return -EIO;
6728cb0e JA	491
6728cb0e JA	492	q = container_of(kobj, struct request_queue, kobj);
8324aa91	493	mutex_lock(&q->sysfs_lock);
3f3299d5	494	if (blk_queue_dying(q)) {
8324aa91 JA	495	mutex_unlock(&q->sysfs_lock);
	496	return -ENOENT;
	497	}
	498	res = entry->store(q, page, length);
	499	mutex_unlock(&q->sysfs_lock);
	500	return res;
	501	}
	502
548bc8e1 TH	503	static void blk_free_queue_rcu(struct rcu_head *rcu_head)
	504	{
	505	struct request_queue *q = container_of(rcu_head, struct request_queue,
	506	rcu_head);
	507	kmem_cache_free(blk_requestq_cachep, q);
	508	}
	509
8324aa91	510	/**
499337bb AM	511	* blk_release_queue: - release a &struct request_queue when it is no longer needed
499337bb AM	512	* @kobj: the kobj belonging to the request queue to be released
8324aa91 JA	513	*
8324aa91 JA	514	* Description:
499337bb	515	* blk_release_queue is the pair to blk_init_queue() or
8324aa91 JA	516	* blk_queue_make_request(). It should be called when a request queue is
	517	* being released; typically when a block device is being de-registered.
	518	* Currently, its primary task it to free all the &struct request
	519	* structures that were allocated to the queue and the queue itself.
	520	*
	521	* Caveat:
	522	* Hopefully the low level driver will have finished any
	523	* outstanding requests first...
	524	**/
	525	static void blk_release_queue(struct kobject *kobj)
	526	{
	527	struct request_queue *q =
	528	container_of(kobj, struct request_queue, kobj);
8324aa91 JA	529
	530	blk_sync_queue(q);
	531
e8989fae TH	532	blkcg_exit_queue(q);
e8989fae TH	533
7e5a8794 TH	534	if (q->elevator) {
	535	spin_lock_irq(q->queue_lock);
	536	ioc_clear_queue(q);
	537	spin_unlock_irq(q->queue_lock);
777eb1bf	538	elevator_exit(q->elevator);
7e5a8794	539	}
777eb1bf	540
a051661c	541	blk_exit_rl(&q->root_rl);
8324aa91 JA	542
	543	if (q->queue_tags)
	544	__blk_queue_free_tags(q);
	545
320ae51f JA	546	percpu_counter_destroy(&q->mq_usage_counter);
	547
	548	if (q->mq_ops)
	549	blk_mq_free_queue(q);
	550
8324aa91 JA	551	blk_trace_shutdown(q);
	552
	553	bdi_destroy(&q->backing_dev_info);
a73f730d TH	554
a73f730d TH	555	ida_simple_remove(&blk_queue_ida, q->id);
548bc8e1	556	call_rcu(&q->rcu_head, blk_free_queue_rcu);
8324aa91 JA	557	}
8324aa91 JA	558
52cf25d0	559	static const struct sysfs_ops queue_sysfs_ops = {
8324aa91 JA	560	.show = queue_attr_show,
	561	.store = queue_attr_store,
	562	};
	563
	564	struct kobj_type blk_queue_ktype = {
	565	.sysfs_ops = &queue_sysfs_ops,
	566	.default_attrs = default_attrs,
	567	.release = blk_release_queue,
	568	};
	569
	570	int blk_register_queue(struct gendisk *disk)
	571	{
	572	int ret;
1d54ad6d	573	struct device *dev = disk_to_dev(disk);
8324aa91 JA	574	struct request_queue *q = disk->queue;
8324aa91 JA	575
fb199746	576	if (WARN_ON(!q))
8324aa91 JA	577	return -ENXIO;
8324aa91 JA	578
749fefe6 TH	579	/*
	580	* Initialization must be complete by now. Finish the initial
	581	* bypass from queue allocation.
	582	*/
	583	blk_queue_bypass_end(q);
320ae51f	584	queue_flag_set_unlocked(QUEUE_FLAG_INIT_DONE, q);
749fefe6	585
1d54ad6d LZ	586	ret = blk_trace_init_sysfs(dev);
	587	if (ret)
	588	return ret;
	589
c9059598	590	ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
ed5302d3 LY	591	if (ret < 0) {
ed5302d3 LY	592	blk_trace_remove_sysfs(dev);
8324aa91	593	return ret;
ed5302d3	594	}
8324aa91 JA	595
	596	kobject_uevent(&q->kobj, KOBJ_ADD);
	597
320ae51f JA	598	if (q->mq_ops)
	599	blk_mq_register_disk(disk);
	600
cd43e26f MP	601	if (!q->request_fn)
	602	return 0;
	603
8324aa91 JA	604	ret = elv_register_queue(q);
	605	if (ret) {
	606	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	607	kobject_del(&q->kobj);
80656b67	608	blk_trace_remove_sysfs(dev);
c87ffbb8	609	kobject_put(&dev->kobj);
8324aa91 JA	610	return ret;
	611	}
	612
	613	return 0;
	614	}
	615
	616	void blk_unregister_queue(struct gendisk *disk)
	617	{
	618	struct request_queue *q = disk->queue;
	619
fb199746 AM	620	if (WARN_ON(!q))
	621	return;
	622
320ae51f JA	623	if (q->mq_ops)
	624	blk_mq_unregister_disk(disk);
	625
48c0d4d4	626	if (q->request_fn)
8324aa91 JA	627	elv_unregister_queue(q);
8324aa91 JA	628
48c0d4d4 ZK	629	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	630	kobject_del(&q->kobj);
	631	blk_trace_remove_sysfs(disk_to_dev(disk));
	632	kobject_put(&disk_to_dev(disk)->kobj);
8324aa91	633	}