[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/backing-dev.h>
#include <linux/blktrace_api.h>
#include <linux/blk-mq.h>
#include <linux/blk-cgroup.h>

#include "blk.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)
{
	unsigned long nr;
	int ret, err;

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

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

	if (nr < BLKDEV_MIN_RQ)
		nr = BLKDEV_MIN_RQ;

	if (q->request_fn)
		err = blk_update_nr_requests(q, nr);
	else
		err = blk_mq_update_nr_requests(q, nr);

	if (err)
		return err;

	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_hw_show(struct request_queue *q, char *page)
{
	unsigned long long val;

	val = q->limits.max_hw_discard_sectors << 9;
	return sprintf(page, "%llu\n", val);
}

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

	if (ret < 0)
		return ret;

	if (max_discard & (q->limits.discard_granularity - 1))
		return -EINVAL;

	max_discard >>= 9;
	if (max_discard > UINT_MAX)
		return -EINVAL;

	if (max_discard > q->limits.max_hw_discard_sectors)
		max_discard = q->limits.max_hw_discard_sectors;

	q->limits.max_discard_sectors = max_discard;
	return ret;
}

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_hw_entry = {
	.attr = {.name = "discard_max_hw_bytes", .mode = S_IRUGO },
	.show = queue_discard_max_hw_show,
};

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

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_max_hw_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.
 *
 * Note:
 *     The low level driver must have finished any outstanding requests first
 *     via blk_cleanup_queue().
 **/
static void blk_release_queue(struct kobject *kobj)
{
	struct request_queue *q =
		container_of(kobj, struct request_queue, kobj);

	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);

	if (!q->mq_ops)
		blk_free_flush_queue(q->fq);
	else
		blk_mq_release(q);

	blk_trace_shutdown(q);

	if (q->bio_split)
		bioset_free(q->bio_split);

	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;

	/*
	 * SCSI probing may synchronously create and destroy a lot of
	 * request_queues for non-existent devices.  Shutting down a fully
	 * functional queue takes measureable wallclock time as RCU grace
	 * periods are involved.  To avoid excessive latency in these
	 * cases, a request_queue starts out in a degraded mode which is
	 * faster to shut down and is made fully functional here as
	 * request_queues for non-existent devices never get registered.
	 */
	if (!blk_queue_init_done(q)) {
		queue_flag_set_unlocked(QUEUE_FLAG_INIT_DONE, q);
		blk_queue_bypass_end(q);
		if (q->mq_ops)
			blk_mq_finish_init(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>
66114cad	9	#include <linux/backing-dev.h>
8324aa91	10	#include <linux/blktrace_api.h>
320ae51f	11	#include <linux/blk-mq.h>
eea8f41c	12	#include <linux/blk-cgroup.h>
8324aa91 JA	13
8324aa91 JA	14	#include "blk.h"
3edcc0ce	15	#include "blk-mq.h"
8324aa91 JA	16
	17	struct queue_sysfs_entry {
	18	struct attribute attr;
	19	ssize_t (show)(struct request_queue , char *);
	20	ssize_t (store)(struct request_queue , const char *, size_t);
	21	};
	22
	23	static ssize_t
9cb308ce	24	queue_var_show(unsigned long var, char *page)
8324aa91	25	{
9cb308ce	26	return sprintf(page, "%lu\n", var);
8324aa91 JA	27	}
	28
	29	static ssize_t
	30	queue_var_store(unsigned long var, const char page, size_t count)
	31	{
b1f3b64d DR	32	int err;
	33	unsigned long v;
	34
ed751e68	35	err = kstrtoul(page, 10, &v);
b1f3b64d DR	36	if (err \|\| v > UINT_MAX)
	37	return -EINVAL;
	38
	39	*var = v;
8324aa91	40
8324aa91 JA	41	return count;
	42	}
	43
	44	static ssize_t queue_requests_show(struct request_queue q, char page)
	45	{
	46	return queue_var_show(q->nr_requests, (page));
	47	}
	48
	49	static ssize_t
	50	queue_requests_store(struct request_queue q, const char page, size_t count)
	51	{
8324aa91	52	unsigned long nr;
e3a2b3f9	53	int ret, err;
b8a9ae77	54
e3a2b3f9	55	if (!q->request_fn && !q->mq_ops)
b8a9ae77 JA	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
e3a2b3f9 JA	65	if (q->request_fn)
	66	err = blk_update_nr_requests(q, nr);
	67	else
	68	err = blk_mq_update_nr_requests(q, nr);
	69
	70	if (err)
	71	return err;
	72
8324aa91 JA	73	return ret;
	74	}
	75
	76	static ssize_t queue_ra_show(struct request_queue q, char page)
	77	{
9cb308ce XF	78	unsigned long ra_kb = q->backing_dev_info.ra_pages <<
9cb308ce XF	79	(PAGE_CACHE_SHIFT - 10);
8324aa91 JA	80
	81	return queue_var_show(ra_kb, (page));
	82	}
	83
	84	static ssize_t
	85	queue_ra_store(struct request_queue q, const char page, size_t count)
	86	{
	87	unsigned long ra_kb;
	88	ssize_t ret = queue_var_store(&ra_kb, page, count);
	89
b1f3b64d DR	90	if (ret < 0)
	91	return ret;
	92
8324aa91	93	q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);
8324aa91 JA	94
	95	return ret;
	96	}
	97
	98	static ssize_t queue_max_sectors_show(struct request_queue q, char page)
	99	{
ae03bf63	100	int max_sectors_kb = queue_max_sectors(q) >> 1;
8324aa91 JA	101
	102	return queue_var_show(max_sectors_kb, (page));
	103	}
	104
c77a5710 MP	105	static ssize_t queue_max_segments_show(struct request_queue q, char page)
	106	{
	107	return queue_var_show(queue_max_segments(q), (page));
	108	}
	109
13f05c8d MP	110	static ssize_t queue_max_integrity_segments_show(struct request_queue q, char page)
	111	{
	112	return queue_var_show(q->limits.max_integrity_segments, (page));
	113	}
	114
c77a5710 MP	115	static ssize_t queue_max_segment_size_show(struct request_queue q, char page)
c77a5710 MP	116	{
e692cb66	117	if (blk_queue_cluster(q))
c77a5710 MP	118	return queue_var_show(queue_max_segment_size(q), (page));
	119
	120	return queue_var_show(PAGE_CACHE_SIZE, (page));
	121	}
	122
e1defc4f	123	static ssize_t queue_logical_block_size_show(struct request_queue q, char page)
e68b903c	124	{
e1defc4f	125	return queue_var_show(queue_logical_block_size(q), page);
e68b903c MP	126	}
e68b903c MP	127
c72758f3 MP	128	static ssize_t queue_physical_block_size_show(struct request_queue q, char page)
	129	{
	130	return queue_var_show(queue_physical_block_size(q), page);
	131	}
	132
	133	static ssize_t queue_io_min_show(struct request_queue q, char page)
	134	{
	135	return queue_var_show(queue_io_min(q), page);
	136	}
	137
	138	static ssize_t queue_io_opt_show(struct request_queue q, char page)
	139	{
	140	return queue_var_show(queue_io_opt(q), page);
e68b903c MP	141	}
e68b903c MP	142
86b37281 MP	143	static ssize_t queue_discard_granularity_show(struct request_queue q, char page)
	144	{
	145	return queue_var_show(q->limits.discard_granularity, page);
	146	}
	147
0034af03 JA	148	static ssize_t queue_discard_max_hw_show(struct request_queue q, char page)
	149	{
	150	unsigned long long val;
	151
	152	val = q->limits.max_hw_discard_sectors << 9;
	153	return sprintf(page, "%llu\n", val);
	154	}
	155
86b37281 MP	156	static ssize_t queue_discard_max_show(struct request_queue q, char page)
86b37281 MP	157	{
a934a00a MP	158	return sprintf(page, "%llu\n",
a934a00a MP	159	(unsigned long long)q->limits.max_discard_sectors << 9);
86b37281 MP	160	}
86b37281 MP	161
0034af03 JA	162	static ssize_t queue_discard_max_store(struct request_queue *q,
	163	const char *page, size_t count)
	164	{
	165	unsigned long max_discard;
	166	ssize_t ret = queue_var_store(&max_discard, page, count);
	167
	168	if (ret < 0)
	169	return ret;
	170
	171	if (max_discard & (q->limits.discard_granularity - 1))
	172	return -EINVAL;
	173
	174	max_discard >>= 9;
	175	if (max_discard > UINT_MAX)
	176	return -EINVAL;
	177
	178	if (max_discard > q->limits.max_hw_discard_sectors)
	179	max_discard = q->limits.max_hw_discard_sectors;
	180
	181	q->limits.max_discard_sectors = max_discard;
	182	return ret;
	183	}
	184
98262f27 MP	185	static ssize_t queue_discard_zeroes_data_show(struct request_queue q, char page)
	186	{
	187	return queue_var_show(queue_discard_zeroes_data(q), page);
	188	}
	189
4363ac7c MP	190	static ssize_t queue_write_same_max_show(struct request_queue q, char page)
	191	{
	192	return sprintf(page, "%llu\n",
	193	(unsigned long long)q->limits.max_write_same_sectors << 9);
	194	}
	195
	196
8324aa91 JA	197	static ssize_t
	198	queue_max_sectors_store(struct request_queue q, const char page, size_t count)
	199	{
	200	unsigned long max_sectors_kb,
ae03bf63	201	max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
8324aa91 JA	202	page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
	203	ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
	204
b1f3b64d DR	205	if (ret < 0)
	206	return ret;
	207
8324aa91 JA	208	if (max_sectors_kb > max_hw_sectors_kb \|\| max_sectors_kb < page_kb)
8324aa91 JA	209	return -EINVAL;
7c239517	210
8324aa91	211	spin_lock_irq(q->queue_lock);
c295fc05	212	q->limits.max_sectors = max_sectors_kb << 1;
8324aa91 JA	213	spin_unlock_irq(q->queue_lock);
	214
	215	return ret;
	216	}
	217
	218	static ssize_t queue_max_hw_sectors_show(struct request_queue q, char page)
	219	{
ae03bf63	220	int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
8324aa91 JA	221
	222	return queue_var_show(max_hw_sectors_kb, (page));
	223	}
	224
956bcb7c JA	225	#define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \
	226	static ssize_t \
	227	queue_show_##name(struct request_queue q, char page) \
	228	{ \
	229	int bit; \
	230	bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \
	231	return queue_var_show(neg ? !bit : bit, page); \
	232	} \
	233	static ssize_t \
	234	queue_store_##name(struct request_queue q, const char page, size_t count) \
	235	{ \
	236	unsigned long val; \
	237	ssize_t ret; \
	238	ret = queue_var_store(&val, page, count); \
c678ef52 AB	239	if (ret < 0) \
c678ef52 AB	240	return ret; \
956bcb7c JA	241	if (neg) \
	242	val = !val; \
	243	\
	244	spin_lock_irq(q->queue_lock); \
	245	if (val) \
	246	queue_flag_set(QUEUE_FLAG_##flag, q); \
	247	else \
	248	queue_flag_clear(QUEUE_FLAG_##flag, q); \
	249	spin_unlock_irq(q->queue_lock); \
	250	return ret; \
1308835f BZ	251	}
1308835f BZ	252
956bcb7c JA	253	QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
	254	QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
	255	QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
	256	#undef QUEUE_SYSFS_BIT_FNS
1308835f	257
ac9fafa1 AB	258	static ssize_t queue_nomerges_show(struct request_queue q, char page)
ac9fafa1 AB	259	{
488991e2 AB	260	return queue_var_show((blk_queue_nomerges(q) << 1) \|
488991e2 AB	261	blk_queue_noxmerges(q), page);
ac9fafa1 AB	262	}
	263
	264	static ssize_t queue_nomerges_store(struct request_queue q, const char page,
	265	size_t count)
	266	{
	267	unsigned long nm;
	268	ssize_t ret = queue_var_store(&nm, page, count);
	269
b1f3b64d DR	270	if (ret < 0)
	271	return ret;
	272
bf0f9702	273	spin_lock_irq(q->queue_lock);
488991e2 AB	274	queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
	275	queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
	276	if (nm == 2)
bf0f9702	277	queue_flag_set(QUEUE_FLAG_NOMERGES, q);
488991e2 AB	278	else if (nm)
488991e2 AB	279	queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
bf0f9702	280	spin_unlock_irq(q->queue_lock);
1308835f	281
ac9fafa1 AB	282	return ret;
	283	}
	284
c7c22e4d JA	285	static ssize_t queue_rq_affinity_show(struct request_queue q, char page)
c7c22e4d JA	286	{
9cb308ce	287	bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
5757a6d7	288	bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags);
c7c22e4d	289
5757a6d7	290	return queue_var_show(set << force, page);
c7c22e4d JA	291	}
	292
	293	static ssize_t
	294	queue_rq_affinity_store(struct request_queue q, const char page, size_t count)
	295	{
	296	ssize_t ret = -EINVAL;
0a06ff06	297	#ifdef CONFIG_SMP
c7c22e4d JA	298	unsigned long val;
	299
	300	ret = queue_var_store(&val, page, count);
b1f3b64d DR	301	if (ret < 0)
	302	return ret;
	303
c7c22e4d	304	spin_lock_irq(q->queue_lock);
e8037d49	305	if (val == 2) {
c7c22e4d	306	queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
e8037d49 ES	307	queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
	308	} else if (val == 1) {
	309	queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
	310	queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
	311	} else if (val == 0) {
5757a6d7 DW	312	queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
	313	queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
	314	}
c7c22e4d JA	315	spin_unlock_irq(q->queue_lock);
	316	#endif
	317	return ret;
	318	}
8324aa91 JA	319
	320	static struct queue_sysfs_entry queue_requests_entry = {
	321	.attr = {.name = "nr_requests", .mode = S_IRUGO \| S_IWUSR },
	322	.show = queue_requests_show,
	323	.store = queue_requests_store,
	324	};
	325
	326	static struct queue_sysfs_entry queue_ra_entry = {
	327	.attr = {.name = "read_ahead_kb", .mode = S_IRUGO \| S_IWUSR },
	328	.show = queue_ra_show,
	329	.store = queue_ra_store,
	330	};
	331
	332	static struct queue_sysfs_entry queue_max_sectors_entry = {
	333	.attr = {.name = "max_sectors_kb", .mode = S_IRUGO \| S_IWUSR },
	334	.show = queue_max_sectors_show,
	335	.store = queue_max_sectors_store,
	336	};
	337
	338	static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
	339	.attr = {.name = "max_hw_sectors_kb", .mode = S_IRUGO },
	340	.show = queue_max_hw_sectors_show,
	341	};
	342
c77a5710 MP	343	static struct queue_sysfs_entry queue_max_segments_entry = {
	344	.attr = {.name = "max_segments", .mode = S_IRUGO },
	345	.show = queue_max_segments_show,
	346	};
	347
13f05c8d MP	348	static struct queue_sysfs_entry queue_max_integrity_segments_entry = {
	349	.attr = {.name = "max_integrity_segments", .mode = S_IRUGO },
	350	.show = queue_max_integrity_segments_show,
	351	};
	352
c77a5710 MP	353	static struct queue_sysfs_entry queue_max_segment_size_entry = {
	354	.attr = {.name = "max_segment_size", .mode = S_IRUGO },
	355	.show = queue_max_segment_size_show,
	356	};
	357
8324aa91 JA	358	static struct queue_sysfs_entry queue_iosched_entry = {
	359	.attr = {.name = "scheduler", .mode = S_IRUGO \| S_IWUSR },
	360	.show = elv_iosched_show,
	361	.store = elv_iosched_store,
	362	};
	363
e68b903c MP	364	static struct queue_sysfs_entry queue_hw_sector_size_entry = {
e68b903c MP	365	.attr = {.name = "hw_sector_size", .mode = S_IRUGO },
e1defc4f MP	366	.show = queue_logical_block_size_show,
	367	};
	368
	369	static struct queue_sysfs_entry queue_logical_block_size_entry = {
	370	.attr = {.name = "logical_block_size", .mode = S_IRUGO },
	371	.show = queue_logical_block_size_show,
e68b903c MP	372	};
e68b903c MP	373
c72758f3 MP	374	static struct queue_sysfs_entry queue_physical_block_size_entry = {
	375	.attr = {.name = "physical_block_size", .mode = S_IRUGO },
	376	.show = queue_physical_block_size_show,
	377	};
	378
	379	static struct queue_sysfs_entry queue_io_min_entry = {
	380	.attr = {.name = "minimum_io_size", .mode = S_IRUGO },
	381	.show = queue_io_min_show,
	382	};
	383
	384	static struct queue_sysfs_entry queue_io_opt_entry = {
	385	.attr = {.name = "optimal_io_size", .mode = S_IRUGO },
	386	.show = queue_io_opt_show,
e68b903c MP	387	};
e68b903c MP	388
86b37281 MP	389	static struct queue_sysfs_entry queue_discard_granularity_entry = {
	390	.attr = {.name = "discard_granularity", .mode = S_IRUGO },
	391	.show = queue_discard_granularity_show,
	392	};
	393
0034af03 JA	394	static struct queue_sysfs_entry queue_discard_max_hw_entry = {
	395	.attr = {.name = "discard_max_hw_bytes", .mode = S_IRUGO },
	396	.show = queue_discard_max_hw_show,
	397	};
	398
86b37281	399	static struct queue_sysfs_entry queue_discard_max_entry = {
0034af03	400	.attr = {.name = "discard_max_bytes", .mode = S_IRUGO \| S_IWUSR },
86b37281	401	.show = queue_discard_max_show,
0034af03	402	.store = queue_discard_max_store,
86b37281 MP	403	};
86b37281 MP	404
98262f27 MP	405	static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
	406	.attr = {.name = "discard_zeroes_data", .mode = S_IRUGO },
	407	.show = queue_discard_zeroes_data_show,
	408	};
	409
4363ac7c MP	410	static struct queue_sysfs_entry queue_write_same_max_entry = {
	411	.attr = {.name = "write_same_max_bytes", .mode = S_IRUGO },
	412	.show = queue_write_same_max_show,
	413	};
	414
1308835f BZ	415	static struct queue_sysfs_entry queue_nonrot_entry = {
1308835f BZ	416	.attr = {.name = "rotational", .mode = S_IRUGO \| S_IWUSR },
956bcb7c JA	417	.show = queue_show_nonrot,
956bcb7c JA	418	.store = queue_store_nonrot,
1308835f BZ	419	};
1308835f BZ	420
ac9fafa1 AB	421	static struct queue_sysfs_entry queue_nomerges_entry = {
	422	.attr = {.name = "nomerges", .mode = S_IRUGO \| S_IWUSR },
	423	.show = queue_nomerges_show,
	424	.store = queue_nomerges_store,
	425	};
	426
c7c22e4d JA	427	static struct queue_sysfs_entry queue_rq_affinity_entry = {
	428	.attr = {.name = "rq_affinity", .mode = S_IRUGO \| S_IWUSR },
	429	.show = queue_rq_affinity_show,
	430	.store = queue_rq_affinity_store,
	431	};
	432
bc58ba94 JA	433	static struct queue_sysfs_entry queue_iostats_entry = {
bc58ba94 JA	434	.attr = {.name = "iostats", .mode = S_IRUGO \| S_IWUSR },
956bcb7c JA	435	.show = queue_show_iostats,
956bcb7c JA	436	.store = queue_store_iostats,
bc58ba94 JA	437	};
bc58ba94 JA	438
e2e1a148 JA	439	static struct queue_sysfs_entry queue_random_entry = {
e2e1a148 JA	440	.attr = {.name = "add_random", .mode = S_IRUGO \| S_IWUSR },
956bcb7c JA	441	.show = queue_show_random,
956bcb7c JA	442	.store = queue_store_random,
e2e1a148 JA	443	};
e2e1a148 JA	444
8324aa91 JA	445	static struct attribute *default_attrs[] = {
	446	&queue_requests_entry.attr,
	447	&queue_ra_entry.attr,
	448	&queue_max_hw_sectors_entry.attr,
	449	&queue_max_sectors_entry.attr,
c77a5710	450	&queue_max_segments_entry.attr,
13f05c8d	451	&queue_max_integrity_segments_entry.attr,
c77a5710	452	&queue_max_segment_size_entry.attr,
8324aa91	453	&queue_iosched_entry.attr,
e68b903c	454	&queue_hw_sector_size_entry.attr,
e1defc4f	455	&queue_logical_block_size_entry.attr,
c72758f3 MP	456	&queue_physical_block_size_entry.attr,
	457	&queue_io_min_entry.attr,
	458	&queue_io_opt_entry.attr,
86b37281 MP	459	&queue_discard_granularity_entry.attr,
86b37281 MP	460	&queue_discard_max_entry.attr,
0034af03	461	&queue_discard_max_hw_entry.attr,
98262f27	462	&queue_discard_zeroes_data_entry.attr,
4363ac7c	463	&queue_write_same_max_entry.attr,
1308835f	464	&queue_nonrot_entry.attr,
ac9fafa1	465	&queue_nomerges_entry.attr,
c7c22e4d	466	&queue_rq_affinity_entry.attr,
bc58ba94	467	&queue_iostats_entry.attr,
e2e1a148	468	&queue_random_entry.attr,
8324aa91 JA	469	NULL,
	470	};
	471
	472	#define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
	473
	474	static ssize_t
	475	queue_attr_show(struct kobject kobj, struct attribute attr, char *page)
	476	{
	477	struct queue_sysfs_entry *entry = to_queue(attr);
	478	struct request_queue *q =
	479	container_of(kobj, struct request_queue, kobj);
	480	ssize_t res;
	481
	482	if (!entry->show)
	483	return -EIO;
	484	mutex_lock(&q->sysfs_lock);
3f3299d5	485	if (blk_queue_dying(q)) {
8324aa91 JA	486	mutex_unlock(&q->sysfs_lock);
	487	return -ENOENT;
	488	}
	489	res = entry->show(q, page);
	490	mutex_unlock(&q->sysfs_lock);
	491	return res;
	492	}
	493
	494	static ssize_t
	495	queue_attr_store(struct kobject kobj, struct attribute attr,
	496	const char *page, size_t length)
	497	{
	498	struct queue_sysfs_entry *entry = to_queue(attr);
6728cb0e	499	struct request_queue *q;
8324aa91 JA	500	ssize_t res;
	501
	502	if (!entry->store)
	503	return -EIO;
6728cb0e JA	504
6728cb0e JA	505	q = container_of(kobj, struct request_queue, kobj);
8324aa91	506	mutex_lock(&q->sysfs_lock);
3f3299d5	507	if (blk_queue_dying(q)) {
8324aa91 JA	508	mutex_unlock(&q->sysfs_lock);
	509	return -ENOENT;
	510	}
	511	res = entry->store(q, page, length);
	512	mutex_unlock(&q->sysfs_lock);
	513	return res;
	514	}
	515
548bc8e1 TH	516	static void blk_free_queue_rcu(struct rcu_head *rcu_head)
	517	{
	518	struct request_queue *q = container_of(rcu_head, struct request_queue,
	519	rcu_head);
	520	kmem_cache_free(blk_requestq_cachep, q);
	521	}
	522
8324aa91	523	/**
499337bb AM	524	* blk_release_queue: - release a &struct request_queue when it is no longer needed
499337bb AM	525	* @kobj: the kobj belonging to the request queue to be released
8324aa91 JA	526	*
8324aa91 JA	527	* Description:
499337bb	528	* blk_release_queue is the pair to blk_init_queue() or
8324aa91 JA	529	* blk_queue_make_request(). It should be called when a request queue is
	530	* being released; typically when a block device is being de-registered.
	531	* Currently, its primary task it to free all the &struct request
	532	* structures that were allocated to the queue and the queue itself.
	533	*
45a9c9d9 BVA	534	* Note:
	535	* The low level driver must have finished any outstanding requests first
	536	* via blk_cleanup_queue().
8324aa91 JA	537	**/
	538	static void blk_release_queue(struct kobject *kobj)
	539	{
	540	struct request_queue *q =
	541	container_of(kobj, struct request_queue, kobj);
8324aa91	542
e8989fae TH	543	blkcg_exit_queue(q);
e8989fae TH	544
7e5a8794 TH	545	if (q->elevator) {
	546	spin_lock_irq(q->queue_lock);
	547	ioc_clear_queue(q);
	548	spin_unlock_irq(q->queue_lock);
777eb1bf	549	elevator_exit(q->elevator);
7e5a8794	550	}
777eb1bf	551
a051661c	552	blk_exit_rl(&q->root_rl);
8324aa91 JA	553
	554	if (q->queue_tags)
	555	__blk_queue_free_tags(q);
	556
45a9c9d9	557	if (!q->mq_ops)
f70ced09	558	blk_free_flush_queue(q->fq);
e09aae7e ML	559	else
e09aae7e ML	560	blk_mq_release(q);
18741986	561
8324aa91 JA	562	blk_trace_shutdown(q);
8324aa91 JA	563
54efd50b KO	564	if (q->bio_split)
	565	bioset_free(q->bio_split);
	566
a73f730d	567	ida_simple_remove(&blk_queue_ida, q->id);
548bc8e1	568	call_rcu(&q->rcu_head, blk_free_queue_rcu);
8324aa91 JA	569	}
8324aa91 JA	570
52cf25d0	571	static const struct sysfs_ops queue_sysfs_ops = {
8324aa91 JA	572	.show = queue_attr_show,
	573	.store = queue_attr_store,
	574	};
	575
	576	struct kobj_type blk_queue_ktype = {
	577	.sysfs_ops = &queue_sysfs_ops,
	578	.default_attrs = default_attrs,
	579	.release = blk_release_queue,
	580	};
	581
	582	int blk_register_queue(struct gendisk *disk)
	583	{
	584	int ret;
1d54ad6d	585	struct device *dev = disk_to_dev(disk);
8324aa91 JA	586	struct request_queue *q = disk->queue;
8324aa91 JA	587
fb199746	588	if (WARN_ON(!q))
8324aa91 JA	589	return -ENXIO;
8324aa91 JA	590
749fefe6	591	/*
17497acb TH	592	* SCSI probing may synchronously create and destroy a lot of
	593	* request_queues for non-existent devices. Shutting down a fully
	594	* functional queue takes measureable wallclock time as RCU grace
	595	* periods are involved. To avoid excessive latency in these
	596	* cases, a request_queue starts out in a degraded mode which is
	597	* faster to shut down and is made fully functional here as
	598	* request_queues for non-existent devices never get registered.
749fefe6	599	*/
df35c7c9 AS	600	if (!blk_queue_init_done(q)) {
	601	queue_flag_set_unlocked(QUEUE_FLAG_INIT_DONE, q);
	602	blk_queue_bypass_end(q);
17497acb TH	603	if (q->mq_ops)
17497acb TH	604	blk_mq_finish_init(q);
df35c7c9	605	}
749fefe6	606
1d54ad6d LZ	607	ret = blk_trace_init_sysfs(dev);
	608	if (ret)
	609	return ret;
	610
c9059598	611	ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
ed5302d3 LY	612	if (ret < 0) {
ed5302d3 LY	613	blk_trace_remove_sysfs(dev);
8324aa91	614	return ret;
ed5302d3	615	}
8324aa91 JA	616
	617	kobject_uevent(&q->kobj, KOBJ_ADD);
	618
320ae51f JA	619	if (q->mq_ops)
	620	blk_mq_register_disk(disk);
	621
cd43e26f MP	622	if (!q->request_fn)
	623	return 0;
	624
8324aa91 JA	625	ret = elv_register_queue(q);
	626	if (ret) {
	627	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	628	kobject_del(&q->kobj);
80656b67	629	blk_trace_remove_sysfs(dev);
c87ffbb8	630	kobject_put(&dev->kobj);
8324aa91 JA	631	return ret;
	632	}
	633
	634	return 0;
	635	}
	636
	637	void blk_unregister_queue(struct gendisk *disk)
	638	{
	639	struct request_queue *q = disk->queue;
	640
fb199746 AM	641	if (WARN_ON(!q))
	642	return;
	643
320ae51f JA	644	if (q->mq_ops)
	645	blk_mq_unregister_disk(disk);
	646
48c0d4d4	647	if (q->request_fn)
8324aa91 JA	648	elv_unregister_queue(q);
8324aa91 JA	649
48c0d4d4 ZK	650	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	651	kobject_del(&q->kobj);
	652	blk_trace_remove_sysfs(disk_to_dev(disk));
	653	kobject_put(&disk_to_dev(disk)->kobj);
8324aa91	654	}