[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"
#include "blk-mq.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);

	kfree(q->flush_rq);

	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"
3edcc0ce	14	#include "blk-mq.h"
8324aa91 JA	15
	16	struct queue_sysfs_entry {
	17	struct attribute attr;
	18	ssize_t (show)(struct request_queue , char *);
	19	ssize_t (store)(struct request_queue , const char *, size_t);
	20	};
	21
	22	static ssize_t
9cb308ce	23	queue_var_show(unsigned long var, char *page)
8324aa91	24	{
9cb308ce	25	return sprintf(page, "%lu\n", var);
8324aa91 JA	26	}
	27
	28	static ssize_t
	29	queue_var_store(unsigned long var, const char page, size_t count)
	30	{
b1f3b64d DR	31	int err;
	32	unsigned long v;
	33
ed751e68	34	err = kstrtoul(page, 10, &v);
b1f3b64d DR	35	if (err \|\| v > UINT_MAX)
	36	return -EINVAL;
	37
	38	*var = v;
8324aa91	39
8324aa91 JA	40	return count;
	41	}
	42
	43	static ssize_t queue_requests_show(struct request_queue q, char page)
	44	{
	45	return queue_var_show(q->nr_requests, (page));
	46	}
	47
	48	static ssize_t
	49	queue_requests_store(struct request_queue q, const char page, size_t count)
	50	{
a051661c	51	struct request_list *rl;
8324aa91	52	unsigned long nr;
b8a9ae77 JA	53	int ret;
	54
	55	if (!q->request_fn)
	56	return -EINVAL;
	57
	58	ret = queue_var_store(&nr, page, count);
b1f3b64d DR	59	if (ret < 0)
	60	return ret;
	61
8324aa91 JA	62	if (nr < BLKDEV_MIN_RQ)
	63	nr = BLKDEV_MIN_RQ;
	64
	65	spin_lock_irq(q->queue_lock);
	66	q->nr_requests = nr;
	67	blk_queue_congestion_threshold(q);
	68
a051661c TH	69	/* congestion isn't cgroup aware and follows root blkcg for now */
	70	rl = &q->root_rl;
	71
1faa16d2 JA	72	if (rl->count[BLK_RW_SYNC] >= queue_congestion_on_threshold(q))
	73	blk_set_queue_congested(q, BLK_RW_SYNC);
	74	else if (rl->count[BLK_RW_SYNC] < queue_congestion_off_threshold(q))
	75	blk_clear_queue_congested(q, BLK_RW_SYNC);
	76
	77	if (rl->count[BLK_RW_ASYNC] >= queue_congestion_on_threshold(q))
	78	blk_set_queue_congested(q, BLK_RW_ASYNC);
	79	else if (rl->count[BLK_RW_ASYNC] < queue_congestion_off_threshold(q))
	80	blk_clear_queue_congested(q, BLK_RW_ASYNC);
	81
a051661c TH	82	blk_queue_for_each_rl(rl, q) {
	83	if (rl->count[BLK_RW_SYNC] >= q->nr_requests) {
	84	blk_set_rl_full(rl, BLK_RW_SYNC);
	85	} else {
	86	blk_clear_rl_full(rl, BLK_RW_SYNC);
	87	wake_up(&rl->wait[BLK_RW_SYNC]);
	88	}
	89
	90	if (rl->count[BLK_RW_ASYNC] >= q->nr_requests) {
	91	blk_set_rl_full(rl, BLK_RW_ASYNC);
	92	} else {
	93	blk_clear_rl_full(rl, BLK_RW_ASYNC);
	94	wake_up(&rl->wait[BLK_RW_ASYNC]);
	95	}
8324aa91 JA	96	}
8324aa91 JA	97
8324aa91 JA	98	spin_unlock_irq(q->queue_lock);
	99	return ret;
	100	}
	101
	102	static ssize_t queue_ra_show(struct request_queue q, char page)
	103	{
9cb308ce XF	104	unsigned long ra_kb = q->backing_dev_info.ra_pages <<
9cb308ce XF	105	(PAGE_CACHE_SHIFT - 10);
8324aa91 JA	106
	107	return queue_var_show(ra_kb, (page));
	108	}
	109
	110	static ssize_t
	111	queue_ra_store(struct request_queue q, const char page, size_t count)
	112	{
	113	unsigned long ra_kb;
	114	ssize_t ret = queue_var_store(&ra_kb, page, count);
	115
b1f3b64d DR	116	if (ret < 0)
	117	return ret;
	118
8324aa91	119	q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);
8324aa91 JA	120
	121	return ret;
	122	}
	123
	124	static ssize_t queue_max_sectors_show(struct request_queue q, char page)
	125	{
ae03bf63	126	int max_sectors_kb = queue_max_sectors(q) >> 1;
8324aa91 JA	127
	128	return queue_var_show(max_sectors_kb, (page));
	129	}
	130
c77a5710 MP	131	static ssize_t queue_max_segments_show(struct request_queue q, char page)
	132	{
	133	return queue_var_show(queue_max_segments(q), (page));
	134	}
	135
13f05c8d MP	136	static ssize_t queue_max_integrity_segments_show(struct request_queue q, char page)
	137	{
	138	return queue_var_show(q->limits.max_integrity_segments, (page));
	139	}
	140
c77a5710 MP	141	static ssize_t queue_max_segment_size_show(struct request_queue q, char page)
c77a5710 MP	142	{
e692cb66	143	if (blk_queue_cluster(q))
c77a5710 MP	144	return queue_var_show(queue_max_segment_size(q), (page));
	145
	146	return queue_var_show(PAGE_CACHE_SIZE, (page));
	147	}
	148
e1defc4f	149	static ssize_t queue_logical_block_size_show(struct request_queue q, char page)
e68b903c	150	{
e1defc4f	151	return queue_var_show(queue_logical_block_size(q), page);
e68b903c MP	152	}
e68b903c MP	153
c72758f3 MP	154	static ssize_t queue_physical_block_size_show(struct request_queue q, char page)
	155	{
	156	return queue_var_show(queue_physical_block_size(q), page);
	157	}
	158
	159	static ssize_t queue_io_min_show(struct request_queue q, char page)
	160	{
	161	return queue_var_show(queue_io_min(q), page);
	162	}
	163
	164	static ssize_t queue_io_opt_show(struct request_queue q, char page)
	165	{
	166	return queue_var_show(queue_io_opt(q), page);
e68b903c MP	167	}
e68b903c MP	168
86b37281 MP	169	static ssize_t queue_discard_granularity_show(struct request_queue q, char page)
	170	{
	171	return queue_var_show(q->limits.discard_granularity, page);
	172	}
	173
	174	static ssize_t queue_discard_max_show(struct request_queue q, char page)
	175	{
a934a00a MP	176	return sprintf(page, "%llu\n",
a934a00a MP	177	(unsigned long long)q->limits.max_discard_sectors << 9);
86b37281 MP	178	}
86b37281 MP	179
98262f27 MP	180	static ssize_t queue_discard_zeroes_data_show(struct request_queue q, char page)
	181	{
	182	return queue_var_show(queue_discard_zeroes_data(q), page);
	183	}
	184
4363ac7c MP	185	static ssize_t queue_write_same_max_show(struct request_queue q, char page)
	186	{
	187	return sprintf(page, "%llu\n",
	188	(unsigned long long)q->limits.max_write_same_sectors << 9);
	189	}
	190
	191
8324aa91 JA	192	static ssize_t
	193	queue_max_sectors_store(struct request_queue q, const char page, size_t count)
	194	{
	195	unsigned long max_sectors_kb,
ae03bf63	196	max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
8324aa91 JA	197	page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
	198	ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
	199
b1f3b64d DR	200	if (ret < 0)
	201	return ret;
	202
8324aa91 JA	203	if (max_sectors_kb > max_hw_sectors_kb \|\| max_sectors_kb < page_kb)
8324aa91 JA	204	return -EINVAL;
7c239517	205
8324aa91	206	spin_lock_irq(q->queue_lock);
c295fc05	207	q->limits.max_sectors = max_sectors_kb << 1;
8324aa91 JA	208	spin_unlock_irq(q->queue_lock);
	209
	210	return ret;
	211	}
	212
	213	static ssize_t queue_max_hw_sectors_show(struct request_queue q, char page)
	214	{
ae03bf63	215	int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
8324aa91 JA	216
	217	return queue_var_show(max_hw_sectors_kb, (page));
	218	}
	219
956bcb7c JA	220	#define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \
	221	static ssize_t \
	222	queue_show_##name(struct request_queue q, char page) \
	223	{ \
	224	int bit; \
	225	bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \
	226	return queue_var_show(neg ? !bit : bit, page); \
	227	} \
	228	static ssize_t \
	229	queue_store_##name(struct request_queue q, const char page, size_t count) \
	230	{ \
	231	unsigned long val; \
	232	ssize_t ret; \
	233	ret = queue_var_store(&val, page, count); \
c678ef52 AB	234	if (ret < 0) \
c678ef52 AB	235	return ret; \
956bcb7c JA	236	if (neg) \
	237	val = !val; \
	238	\
	239	spin_lock_irq(q->queue_lock); \
	240	if (val) \
	241	queue_flag_set(QUEUE_FLAG_##flag, q); \
	242	else \
	243	queue_flag_clear(QUEUE_FLAG_##flag, q); \
	244	spin_unlock_irq(q->queue_lock); \
	245	return ret; \
1308835f BZ	246	}
1308835f BZ	247
956bcb7c JA	248	QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
	249	QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
	250	QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
	251	#undef QUEUE_SYSFS_BIT_FNS
1308835f	252
ac9fafa1 AB	253	static ssize_t queue_nomerges_show(struct request_queue q, char page)
ac9fafa1 AB	254	{
488991e2 AB	255	return queue_var_show((blk_queue_nomerges(q) << 1) \|
488991e2 AB	256	blk_queue_noxmerges(q), page);
ac9fafa1 AB	257	}
	258
	259	static ssize_t queue_nomerges_store(struct request_queue q, const char page,
	260	size_t count)
	261	{
	262	unsigned long nm;
	263	ssize_t ret = queue_var_store(&nm, page, count);
	264
b1f3b64d DR	265	if (ret < 0)
	266	return ret;
	267
bf0f9702	268	spin_lock_irq(q->queue_lock);
488991e2 AB	269	queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
	270	queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
	271	if (nm == 2)
bf0f9702	272	queue_flag_set(QUEUE_FLAG_NOMERGES, q);
488991e2 AB	273	else if (nm)
488991e2 AB	274	queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
bf0f9702	275	spin_unlock_irq(q->queue_lock);
1308835f	276
ac9fafa1 AB	277	return ret;
	278	}
	279
c7c22e4d JA	280	static ssize_t queue_rq_affinity_show(struct request_queue q, char page)
c7c22e4d JA	281	{
9cb308ce	282	bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
5757a6d7	283	bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags);
c7c22e4d	284
5757a6d7	285	return queue_var_show(set << force, page);
c7c22e4d JA	286	}
	287
	288	static ssize_t
	289	queue_rq_affinity_store(struct request_queue q, const char page, size_t count)
	290	{
	291	ssize_t ret = -EINVAL;
0a06ff06	292	#ifdef CONFIG_SMP
c7c22e4d JA	293	unsigned long val;
	294
	295	ret = queue_var_store(&val, page, count);
b1f3b64d DR	296	if (ret < 0)
	297	return ret;
	298
c7c22e4d	299	spin_lock_irq(q->queue_lock);
e8037d49	300	if (val == 2) {
c7c22e4d	301	queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
e8037d49 ES	302	queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
	303	} else if (val == 1) {
	304	queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
	305	queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
	306	} else if (val == 0) {
5757a6d7 DW	307	queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
	308	queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
	309	}
c7c22e4d JA	310	spin_unlock_irq(q->queue_lock);
	311	#endif
	312	return ret;
	313	}
8324aa91 JA	314
	315	static struct queue_sysfs_entry queue_requests_entry = {
	316	.attr = {.name = "nr_requests", .mode = S_IRUGO \| S_IWUSR },
	317	.show = queue_requests_show,
	318	.store = queue_requests_store,
	319	};
	320
	321	static struct queue_sysfs_entry queue_ra_entry = {
	322	.attr = {.name = "read_ahead_kb", .mode = S_IRUGO \| S_IWUSR },
	323	.show = queue_ra_show,
	324	.store = queue_ra_store,
	325	};
	326
	327	static struct queue_sysfs_entry queue_max_sectors_entry = {
	328	.attr = {.name = "max_sectors_kb", .mode = S_IRUGO \| S_IWUSR },
	329	.show = queue_max_sectors_show,
	330	.store = queue_max_sectors_store,
	331	};
	332
	333	static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
	334	.attr = {.name = "max_hw_sectors_kb", .mode = S_IRUGO },
	335	.show = queue_max_hw_sectors_show,
	336	};
	337
c77a5710 MP	338	static struct queue_sysfs_entry queue_max_segments_entry = {
	339	.attr = {.name = "max_segments", .mode = S_IRUGO },
	340	.show = queue_max_segments_show,
	341	};
	342
13f05c8d MP	343	static struct queue_sysfs_entry queue_max_integrity_segments_entry = {
	344	.attr = {.name = "max_integrity_segments", .mode = S_IRUGO },
	345	.show = queue_max_integrity_segments_show,
	346	};
	347
c77a5710 MP	348	static struct queue_sysfs_entry queue_max_segment_size_entry = {
	349	.attr = {.name = "max_segment_size", .mode = S_IRUGO },
	350	.show = queue_max_segment_size_show,
	351	};
	352
8324aa91 JA	353	static struct queue_sysfs_entry queue_iosched_entry = {
	354	.attr = {.name = "scheduler", .mode = S_IRUGO \| S_IWUSR },
	355	.show = elv_iosched_show,
	356	.store = elv_iosched_store,
	357	};
	358
e68b903c MP	359	static struct queue_sysfs_entry queue_hw_sector_size_entry = {
e68b903c MP	360	.attr = {.name = "hw_sector_size", .mode = S_IRUGO },
e1defc4f MP	361	.show = queue_logical_block_size_show,
	362	};
	363
	364	static struct queue_sysfs_entry queue_logical_block_size_entry = {
	365	.attr = {.name = "logical_block_size", .mode = S_IRUGO },
	366	.show = queue_logical_block_size_show,
e68b903c MP	367	};
e68b903c MP	368
c72758f3 MP	369	static struct queue_sysfs_entry queue_physical_block_size_entry = {
	370	.attr = {.name = "physical_block_size", .mode = S_IRUGO },
	371	.show = queue_physical_block_size_show,
	372	};
	373
	374	static struct queue_sysfs_entry queue_io_min_entry = {
	375	.attr = {.name = "minimum_io_size", .mode = S_IRUGO },
	376	.show = queue_io_min_show,
	377	};
	378
	379	static struct queue_sysfs_entry queue_io_opt_entry = {
	380	.attr = {.name = "optimal_io_size", .mode = S_IRUGO },
	381	.show = queue_io_opt_show,
e68b903c MP	382	};
e68b903c MP	383
86b37281 MP	384	static struct queue_sysfs_entry queue_discard_granularity_entry = {
	385	.attr = {.name = "discard_granularity", .mode = S_IRUGO },
	386	.show = queue_discard_granularity_show,
	387	};
	388
	389	static struct queue_sysfs_entry queue_discard_max_entry = {
	390	.attr = {.name = "discard_max_bytes", .mode = S_IRUGO },
	391	.show = queue_discard_max_show,
	392	};
	393
98262f27 MP	394	static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
	395	.attr = {.name = "discard_zeroes_data", .mode = S_IRUGO },
	396	.show = queue_discard_zeroes_data_show,
	397	};
	398
4363ac7c MP	399	static struct queue_sysfs_entry queue_write_same_max_entry = {
	400	.attr = {.name = "write_same_max_bytes", .mode = S_IRUGO },
	401	.show = queue_write_same_max_show,
	402	};
	403
1308835f BZ	404	static struct queue_sysfs_entry queue_nonrot_entry = {
1308835f BZ	405	.attr = {.name = "rotational", .mode = S_IRUGO \| S_IWUSR },
956bcb7c JA	406	.show = queue_show_nonrot,
956bcb7c JA	407	.store = queue_store_nonrot,
1308835f BZ	408	};
1308835f BZ	409
ac9fafa1 AB	410	static struct queue_sysfs_entry queue_nomerges_entry = {
	411	.attr = {.name = "nomerges", .mode = S_IRUGO \| S_IWUSR },
	412	.show = queue_nomerges_show,
	413	.store = queue_nomerges_store,
	414	};
	415
c7c22e4d JA	416	static struct queue_sysfs_entry queue_rq_affinity_entry = {
	417	.attr = {.name = "rq_affinity", .mode = S_IRUGO \| S_IWUSR },
	418	.show = queue_rq_affinity_show,
	419	.store = queue_rq_affinity_store,
	420	};
	421
bc58ba94 JA	422	static struct queue_sysfs_entry queue_iostats_entry = {
bc58ba94 JA	423	.attr = {.name = "iostats", .mode = S_IRUGO \| S_IWUSR },
956bcb7c JA	424	.show = queue_show_iostats,
956bcb7c JA	425	.store = queue_store_iostats,
bc58ba94 JA	426	};
bc58ba94 JA	427
e2e1a148 JA	428	static struct queue_sysfs_entry queue_random_entry = {
e2e1a148 JA	429	.attr = {.name = "add_random", .mode = S_IRUGO \| S_IWUSR },
956bcb7c JA	430	.show = queue_show_random,
956bcb7c JA	431	.store = queue_store_random,
e2e1a148 JA	432	};
e2e1a148 JA	433
8324aa91 JA	434	static struct attribute *default_attrs[] = {
	435	&queue_requests_entry.attr,
	436	&queue_ra_entry.attr,
	437	&queue_max_hw_sectors_entry.attr,
	438	&queue_max_sectors_entry.attr,
c77a5710	439	&queue_max_segments_entry.attr,
13f05c8d	440	&queue_max_integrity_segments_entry.attr,
c77a5710	441	&queue_max_segment_size_entry.attr,
8324aa91	442	&queue_iosched_entry.attr,
e68b903c	443	&queue_hw_sector_size_entry.attr,
e1defc4f	444	&queue_logical_block_size_entry.attr,
c72758f3 MP	445	&queue_physical_block_size_entry.attr,
	446	&queue_io_min_entry.attr,
	447	&queue_io_opt_entry.attr,
86b37281 MP	448	&queue_discard_granularity_entry.attr,
86b37281 MP	449	&queue_discard_max_entry.attr,
98262f27	450	&queue_discard_zeroes_data_entry.attr,
4363ac7c	451	&queue_write_same_max_entry.attr,
1308835f	452	&queue_nonrot_entry.attr,
ac9fafa1	453	&queue_nomerges_entry.attr,
c7c22e4d	454	&queue_rq_affinity_entry.attr,
bc58ba94	455	&queue_iostats_entry.attr,
e2e1a148	456	&queue_random_entry.attr,
8324aa91 JA	457	NULL,
	458	};
	459
	460	#define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
	461
	462	static ssize_t
	463	queue_attr_show(struct kobject kobj, struct attribute attr, char *page)
	464	{
	465	struct queue_sysfs_entry *entry = to_queue(attr);
	466	struct request_queue *q =
	467	container_of(kobj, struct request_queue, kobj);
	468	ssize_t res;
	469
	470	if (!entry->show)
	471	return -EIO;
	472	mutex_lock(&q->sysfs_lock);
3f3299d5	473	if (blk_queue_dying(q)) {
8324aa91 JA	474	mutex_unlock(&q->sysfs_lock);
	475	return -ENOENT;
	476	}
	477	res = entry->show(q, page);
	478	mutex_unlock(&q->sysfs_lock);
	479	return res;
	480	}
	481
	482	static ssize_t
	483	queue_attr_store(struct kobject kobj, struct attribute attr,
	484	const char *page, size_t length)
	485	{
	486	struct queue_sysfs_entry *entry = to_queue(attr);
6728cb0e	487	struct request_queue *q;
8324aa91 JA	488	ssize_t res;
	489
	490	if (!entry->store)
	491	return -EIO;
6728cb0e JA	492
6728cb0e JA	493	q = container_of(kobj, struct request_queue, kobj);
8324aa91	494	mutex_lock(&q->sysfs_lock);
3f3299d5	495	if (blk_queue_dying(q)) {
8324aa91 JA	496	mutex_unlock(&q->sysfs_lock);
	497	return -ENOENT;
	498	}
	499	res = entry->store(q, page, length);
	500	mutex_unlock(&q->sysfs_lock);
	501	return res;
	502	}
	503
548bc8e1 TH	504	static void blk_free_queue_rcu(struct rcu_head *rcu_head)
	505	{
	506	struct request_queue *q = container_of(rcu_head, struct request_queue,
	507	rcu_head);
	508	kmem_cache_free(blk_requestq_cachep, q);
	509	}
	510
8324aa91	511	/**
499337bb AM	512	* blk_release_queue: - release a &struct request_queue when it is no longer needed
499337bb AM	513	* @kobj: the kobj belonging to the request queue to be released
8324aa91 JA	514	*
8324aa91 JA	515	* Description:
499337bb	516	* blk_release_queue is the pair to blk_init_queue() or
8324aa91 JA	517	* blk_queue_make_request(). It should be called when a request queue is
	518	* being released; typically when a block device is being de-registered.
	519	* Currently, its primary task it to free all the &struct request
	520	* structures that were allocated to the queue and the queue itself.
	521	*
	522	* Caveat:
	523	* Hopefully the low level driver will have finished any
	524	* outstanding requests first...
	525	**/
	526	static void blk_release_queue(struct kobject *kobj)
	527	{
	528	struct request_queue *q =
	529	container_of(kobj, struct request_queue, kobj);
8324aa91 JA	530
	531	blk_sync_queue(q);
	532
e8989fae TH	533	blkcg_exit_queue(q);
e8989fae TH	534
7e5a8794 TH	535	if (q->elevator) {
	536	spin_lock_irq(q->queue_lock);
	537	ioc_clear_queue(q);
	538	spin_unlock_irq(q->queue_lock);
777eb1bf	539	elevator_exit(q->elevator);
7e5a8794	540	}
777eb1bf	541
a051661c	542	blk_exit_rl(&q->root_rl);
8324aa91 JA	543
	544	if (q->queue_tags)
	545	__blk_queue_free_tags(q);
	546
320ae51f JA	547	percpu_counter_destroy(&q->mq_usage_counter);
	548
	549	if (q->mq_ops)
	550	blk_mq_free_queue(q);
	551
18741986 CH	552	kfree(q->flush_rq);
18741986 CH	553
8324aa91 JA	554	blk_trace_shutdown(q);
	555
	556	bdi_destroy(&q->backing_dev_info);
a73f730d TH	557
a73f730d TH	558	ida_simple_remove(&blk_queue_ida, q->id);
548bc8e1	559	call_rcu(&q->rcu_head, blk_free_queue_rcu);
8324aa91 JA	560	}
8324aa91 JA	561
52cf25d0	562	static const struct sysfs_ops queue_sysfs_ops = {
8324aa91 JA	563	.show = queue_attr_show,
	564	.store = queue_attr_store,
	565	};
	566
	567	struct kobj_type blk_queue_ktype = {
	568	.sysfs_ops = &queue_sysfs_ops,
	569	.default_attrs = default_attrs,
	570	.release = blk_release_queue,
	571	};
	572
	573	int blk_register_queue(struct gendisk *disk)
	574	{
	575	int ret;
1d54ad6d	576	struct device *dev = disk_to_dev(disk);
8324aa91 JA	577	struct request_queue *q = disk->queue;
8324aa91 JA	578
fb199746	579	if (WARN_ON(!q))
8324aa91 JA	580	return -ENXIO;
8324aa91 JA	581
749fefe6 TH	582	/*
	583	* Initialization must be complete by now. Finish the initial
	584	* bypass from queue allocation.
	585	*/
	586	blk_queue_bypass_end(q);
320ae51f	587	queue_flag_set_unlocked(QUEUE_FLAG_INIT_DONE, q);
749fefe6	588
1d54ad6d LZ	589	ret = blk_trace_init_sysfs(dev);
	590	if (ret)
	591	return ret;
	592
c9059598	593	ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
ed5302d3 LY	594	if (ret < 0) {
ed5302d3 LY	595	blk_trace_remove_sysfs(dev);
8324aa91	596	return ret;
ed5302d3	597	}
8324aa91 JA	598
	599	kobject_uevent(&q->kobj, KOBJ_ADD);
	600
320ae51f JA	601	if (q->mq_ops)
	602	blk_mq_register_disk(disk);
	603
cd43e26f MP	604	if (!q->request_fn)
	605	return 0;
	606
8324aa91 JA	607	ret = elv_register_queue(q);
	608	if (ret) {
	609	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	610	kobject_del(&q->kobj);
80656b67	611	blk_trace_remove_sysfs(dev);
c87ffbb8	612	kobject_put(&dev->kobj);
8324aa91 JA	613	return ret;
	614	}
	615
	616	return 0;
	617	}
	618
	619	void blk_unregister_queue(struct gendisk *disk)
	620	{
	621	struct request_queue *q = disk->queue;
	622
fb199746 AM	623	if (WARN_ON(!q))
	624	return;
	625
320ae51f JA	626	if (q->mq_ops)
	627	blk_mq_unregister_disk(disk);
	628
48c0d4d4	629	if (q->request_fn)
8324aa91 JA	630	elv_unregister_queue(q);
8324aa91 JA	631
48c0d4d4 ZK	632	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	633	kobject_del(&q->kobj);
	634	blk_trace_remove_sysfs(disk_to_dev(disk));
	635	kobject_put(&disk_to_dev(disk)->kobj);
8324aa91	636	}