[linux.git] / block / blk-sysfs.c

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

#include "blk.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)
{
	char *p = (char *) page;

	*var = simple_strtoul(p, &p, 10);
	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 = &q->rq;
	unsigned long nr;
	int ret;

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

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

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

	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);

	if (rl->count[BLK_RW_SYNC] >= q->nr_requests) {
		blk_set_queue_full(q, BLK_RW_SYNC);
	} else if (rl->count[BLK_RW_SYNC]+1 <= q->nr_requests) {
		blk_clear_queue_full(q, BLK_RW_SYNC);
		wake_up(&rl->wait[BLK_RW_SYNC]);
	}

	if (rl->count[BLK_RW_ASYNC] >= q->nr_requests) {
		blk_set_queue_full(q, BLK_RW_ASYNC);
	} else if (rl->count[BLK_RW_ASYNC]+1 <= q->nr_requests) {
		blk_clear_queue_full(q, 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);

	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_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_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 (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));
}

static ssize_t queue_nonrot_show(struct request_queue *q, char *page)
{
	return queue_var_show(!blk_queue_nonrot(q), page);
}

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

	spin_lock_irq(q->queue_lock);
	if (nm)
		queue_flag_clear(QUEUE_FLAG_NONROT, q);
	else
		queue_flag_set(QUEUE_FLAG_NONROT, q);
	spin_unlock_irq(q->queue_lock);

	return ret;
}

static ssize_t queue_nomerges_show(struct request_queue *q, char *page)
{
	return queue_var_show(blk_queue_nomerges(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);

	spin_lock_irq(q->queue_lock);
	if (nm)
		queue_flag_set(QUEUE_FLAG_NOMERGES, q);
	else
		queue_flag_clear(QUEUE_FLAG_NOMERGES, 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);

	return queue_var_show(set, page);
}

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

	ret = queue_var_store(&val, page, count);
	spin_lock_irq(q->queue_lock);
	if (val)
		queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
	else
		queue_flag_clear(QUEUE_FLAG_SAME_COMP,  q);
	spin_unlock_irq(q->queue_lock);
#endif
	return ret;
}

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

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

	spin_lock_irq(q->queue_lock);
	if (stats)
		queue_flag_set(QUEUE_FLAG_IO_STAT, q);
	else
		queue_flag_clear(QUEUE_FLAG_IO_STAT, q);
	spin_unlock_irq(q->queue_lock);

	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_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_nonrot_entry = {
	.attr = {.name = "rotational", .mode = S_IRUGO | S_IWUSR },
	.show = queue_nonrot_show,
	.store = queue_nonrot_store,
};

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_iostats_show,
	.store = queue_iostats_store,
};

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_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_nonrot_entry.attr,
	&queue_nomerges_entry.attr,
	&queue_rq_affinity_entry.attr,
	&queue_iostats_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 (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
		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 (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
		mutex_unlock(&q->sysfs_lock);
		return -ENOENT;
	}
	res = entry->store(q, page, length);
	mutex_unlock(&q->sysfs_lock);
	return res;
}

/**
 * blk_cleanup_queue: - release a &struct request_queue when it is no longer needed
 * @kobj:    the kobj belonging of the request queue to be released
 *
 * Description:
 *     blk_cleanup_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);
	struct request_list *rl = &q->rq;

	blk_sync_queue(q);

	if (rl->rq_pool)
		mempool_destroy(rl->rq_pool);

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

	blk_trace_shutdown(q);

	bdi_destroy(&q->backing_dev_info);
	kmem_cache_free(blk_requestq_cachep, q);
}

static 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;

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

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

	kobject_uevent(&q->kobj, KOBJ_ADD);

	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(disk_to_dev(disk));
		return ret;
	}

	return 0;
}

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

	if (WARN_ON(!q))
		return;

	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>
	5	#include <linux/module.h>
	6	#include <linux/bio.h>
	7	#include <linux/blkdev.h>
	8	#include <linux/blktrace_api.h>
	9
	10	#include "blk.h"
	11
	12	struct queue_sysfs_entry {
	13	struct attribute attr;
	14	ssize_t (show)(struct request_queue , char *);
	15	ssize_t (store)(struct request_queue , const char *, size_t);
	16	};
	17
	18	static ssize_t
9cb308ce	19	queue_var_show(unsigned long var, char *page)
8324aa91	20	{
9cb308ce	21	return sprintf(page, "%lu\n", var);
8324aa91 JA	22	}
	23
	24	static ssize_t
	25	queue_var_store(unsigned long var, const char page, size_t count)
	26	{
	27	char p = (char ) page;
	28
	29	*var = simple_strtoul(p, &p, 10);
	30	return count;
	31	}
	32
	33	static ssize_t queue_requests_show(struct request_queue q, char page)
	34	{
	35	return queue_var_show(q->nr_requests, (page));
	36	}
	37
	38	static ssize_t
	39	queue_requests_store(struct request_queue q, const char page, size_t count)
	40	{
	41	struct request_list *rl = &q->rq;
	42	unsigned long nr;
b8a9ae77 JA	43	int ret;
	44
	45	if (!q->request_fn)
	46	return -EINVAL;
	47
	48	ret = queue_var_store(&nr, page, count);
8324aa91 JA	49	if (nr < BLKDEV_MIN_RQ)
	50	nr = BLKDEV_MIN_RQ;
	51
	52	spin_lock_irq(q->queue_lock);
	53	q->nr_requests = nr;
	54	blk_queue_congestion_threshold(q);
	55
1faa16d2 JA	56	if (rl->count[BLK_RW_SYNC] >= queue_congestion_on_threshold(q))
	57	blk_set_queue_congested(q, BLK_RW_SYNC);
	58	else if (rl->count[BLK_RW_SYNC] < queue_congestion_off_threshold(q))
	59	blk_clear_queue_congested(q, BLK_RW_SYNC);
	60
	61	if (rl->count[BLK_RW_ASYNC] >= queue_congestion_on_threshold(q))
	62	blk_set_queue_congested(q, BLK_RW_ASYNC);
	63	else if (rl->count[BLK_RW_ASYNC] < queue_congestion_off_threshold(q))
	64	blk_clear_queue_congested(q, BLK_RW_ASYNC);
	65
	66	if (rl->count[BLK_RW_SYNC] >= q->nr_requests) {
	67	blk_set_queue_full(q, BLK_RW_SYNC);
	68	} else if (rl->count[BLK_RW_SYNC]+1 <= q->nr_requests) {
	69	blk_clear_queue_full(q, BLK_RW_SYNC);
	70	wake_up(&rl->wait[BLK_RW_SYNC]);
8324aa91 JA	71	}
8324aa91 JA	72
1faa16d2 JA	73	if (rl->count[BLK_RW_ASYNC] >= q->nr_requests) {
	74	blk_set_queue_full(q, BLK_RW_ASYNC);
	75	} else if (rl->count[BLK_RW_ASYNC]+1 <= q->nr_requests) {
	76	blk_clear_queue_full(q, BLK_RW_ASYNC);
	77	wake_up(&rl->wait[BLK_RW_ASYNC]);
8324aa91 JA	78	}
	79	spin_unlock_irq(q->queue_lock);
	80	return ret;
	81	}
	82
	83	static ssize_t queue_ra_show(struct request_queue q, char page)
	84	{
9cb308ce XF	85	unsigned long ra_kb = q->backing_dev_info.ra_pages <<
9cb308ce XF	86	(PAGE_CACHE_SHIFT - 10);
8324aa91 JA	87
	88	return queue_var_show(ra_kb, (page));
	89	}
	90
	91	static ssize_t
	92	queue_ra_store(struct request_queue q, const char page, size_t count)
	93	{
	94	unsigned long ra_kb;
	95	ssize_t ret = queue_var_store(&ra_kb, page, count);
	96
8324aa91	97	q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);
8324aa91 JA	98
	99	return ret;
	100	}
	101
	102	static ssize_t queue_max_sectors_show(struct request_queue q, char page)
	103	{
ae03bf63	104	int max_sectors_kb = queue_max_sectors(q) >> 1;
8324aa91 JA	105
	106	return queue_var_show(max_sectors_kb, (page));
	107	}
	108
e1defc4f	109	static ssize_t queue_logical_block_size_show(struct request_queue q, char page)
e68b903c	110	{
e1defc4f	111	return queue_var_show(queue_logical_block_size(q), page);
e68b903c MP	112	}
e68b903c MP	113
c72758f3 MP	114	static ssize_t queue_physical_block_size_show(struct request_queue q, char page)
	115	{
	116	return queue_var_show(queue_physical_block_size(q), page);
	117	}
	118
	119	static ssize_t queue_io_min_show(struct request_queue q, char page)
	120	{
	121	return queue_var_show(queue_io_min(q), page);
	122	}
	123
	124	static ssize_t queue_io_opt_show(struct request_queue q, char page)
	125	{
	126	return queue_var_show(queue_io_opt(q), page);
e68b903c MP	127	}
e68b903c MP	128
8324aa91 JA	129	static ssize_t
	130	queue_max_sectors_store(struct request_queue q, const char page, size_t count)
	131	{
	132	unsigned long max_sectors_kb,
ae03bf63	133	max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
8324aa91 JA	134	page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
	135	ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
	136
	137	if (max_sectors_kb > max_hw_sectors_kb \|\| max_sectors_kb < page_kb)
	138	return -EINVAL;
7c239517	139
8324aa91	140	spin_lock_irq(q->queue_lock);
c295fc05	141	q->limits.max_sectors = max_sectors_kb << 1;
8324aa91 JA	142	spin_unlock_irq(q->queue_lock);
	143
	144	return ret;
	145	}
	146
	147	static ssize_t queue_max_hw_sectors_show(struct request_queue q, char page)
	148	{
ae03bf63	149	int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
8324aa91 JA	150
	151	return queue_var_show(max_hw_sectors_kb, (page));
	152	}
	153
1308835f BZ	154	static ssize_t queue_nonrot_show(struct request_queue q, char page)
	155	{
	156	return queue_var_show(!blk_queue_nonrot(q), page);
	157	}
	158
	159	static ssize_t queue_nonrot_store(struct request_queue q, const char page,
	160	size_t count)
	161	{
	162	unsigned long nm;
	163	ssize_t ret = queue_var_store(&nm, page, count);
	164
	165	spin_lock_irq(q->queue_lock);
	166	if (nm)
	167	queue_flag_clear(QUEUE_FLAG_NONROT, q);
	168	else
	169	queue_flag_set(QUEUE_FLAG_NONROT, q);
	170	spin_unlock_irq(q->queue_lock);
	171
	172	return ret;
	173	}
	174
ac9fafa1 AB	175	static ssize_t queue_nomerges_show(struct request_queue q, char page)
	176	{
	177	return queue_var_show(blk_queue_nomerges(q), page);
	178	}
	179
	180	static ssize_t queue_nomerges_store(struct request_queue q, const char page,
	181	size_t count)
	182	{
	183	unsigned long nm;
	184	ssize_t ret = queue_var_store(&nm, page, count);
	185
bf0f9702	186	spin_lock_irq(q->queue_lock);
ac9fafa1	187	if (nm)
bf0f9702	188	queue_flag_set(QUEUE_FLAG_NOMERGES, q);
ac9fafa1	189	else
bf0f9702	190	queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
bf0f9702	191	spin_unlock_irq(q->queue_lock);
1308835f	192
ac9fafa1 AB	193	return ret;
	194	}
	195
c7c22e4d JA	196	static ssize_t queue_rq_affinity_show(struct request_queue q, char page)
c7c22e4d JA	197	{
9cb308ce	198	bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
c7c22e4d	199
9cb308ce	200	return queue_var_show(set, page);
c7c22e4d JA	201	}
	202
	203	static ssize_t
	204	queue_rq_affinity_store(struct request_queue q, const char page, size_t count)
	205	{
	206	ssize_t ret = -EINVAL;
	207	#if defined(CONFIG_USE_GENERIC_SMP_HELPERS)
	208	unsigned long val;
	209
	210	ret = queue_var_store(&val, page, count);
	211	spin_lock_irq(q->queue_lock);
	212	if (val)
	213	queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
	214	else
	215	queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
	216	spin_unlock_irq(q->queue_lock);
	217	#endif
	218	return ret;
	219	}
8324aa91	220
bc58ba94 JA	221	static ssize_t queue_iostats_show(struct request_queue q, char page)
	222	{
	223	return queue_var_show(blk_queue_io_stat(q), page);
	224	}
	225
	226	static ssize_t queue_iostats_store(struct request_queue q, const char page,
	227	size_t count)
	228	{
	229	unsigned long stats;
	230	ssize_t ret = queue_var_store(&stats, page, count);
	231
	232	spin_lock_irq(q->queue_lock);
	233	if (stats)
	234	queue_flag_set(QUEUE_FLAG_IO_STAT, q);
	235	else
	236	queue_flag_clear(QUEUE_FLAG_IO_STAT, q);
	237	spin_unlock_irq(q->queue_lock);
	238
	239	return ret;
	240	}
	241
8324aa91 JA	242	static struct queue_sysfs_entry queue_requests_entry = {
	243	.attr = {.name = "nr_requests", .mode = S_IRUGO \| S_IWUSR },
	244	.show = queue_requests_show,
	245	.store = queue_requests_store,
	246	};
	247
	248	static struct queue_sysfs_entry queue_ra_entry = {
	249	.attr = {.name = "read_ahead_kb", .mode = S_IRUGO \| S_IWUSR },
	250	.show = queue_ra_show,
	251	.store = queue_ra_store,
	252	};
	253
	254	static struct queue_sysfs_entry queue_max_sectors_entry = {
	255	.attr = {.name = "max_sectors_kb", .mode = S_IRUGO \| S_IWUSR },
	256	.show = queue_max_sectors_show,
	257	.store = queue_max_sectors_store,
	258	};
	259
	260	static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
	261	.attr = {.name = "max_hw_sectors_kb", .mode = S_IRUGO },
	262	.show = queue_max_hw_sectors_show,
	263	};
	264
	265	static struct queue_sysfs_entry queue_iosched_entry = {
	266	.attr = {.name = "scheduler", .mode = S_IRUGO \| S_IWUSR },
	267	.show = elv_iosched_show,
	268	.store = elv_iosched_store,
	269	};
	270
e68b903c MP	271	static struct queue_sysfs_entry queue_hw_sector_size_entry = {
e68b903c MP	272	.attr = {.name = "hw_sector_size", .mode = S_IRUGO },
e1defc4f MP	273	.show = queue_logical_block_size_show,
	274	};
	275
	276	static struct queue_sysfs_entry queue_logical_block_size_entry = {
	277	.attr = {.name = "logical_block_size", .mode = S_IRUGO },
	278	.show = queue_logical_block_size_show,
e68b903c MP	279	};
e68b903c MP	280
c72758f3 MP	281	static struct queue_sysfs_entry queue_physical_block_size_entry = {
	282	.attr = {.name = "physical_block_size", .mode = S_IRUGO },
	283	.show = queue_physical_block_size_show,
	284	};
	285
	286	static struct queue_sysfs_entry queue_io_min_entry = {
	287	.attr = {.name = "minimum_io_size", .mode = S_IRUGO },
	288	.show = queue_io_min_show,
	289	};
	290
	291	static struct queue_sysfs_entry queue_io_opt_entry = {
	292	.attr = {.name = "optimal_io_size", .mode = S_IRUGO },
	293	.show = queue_io_opt_show,
e68b903c MP	294	};
e68b903c MP	295
1308835f BZ	296	static struct queue_sysfs_entry queue_nonrot_entry = {
	297	.attr = {.name = "rotational", .mode = S_IRUGO \| S_IWUSR },
	298	.show = queue_nonrot_show,
	299	.store = queue_nonrot_store,
	300	};
	301
ac9fafa1 AB	302	static struct queue_sysfs_entry queue_nomerges_entry = {
	303	.attr = {.name = "nomerges", .mode = S_IRUGO \| S_IWUSR },
	304	.show = queue_nomerges_show,
	305	.store = queue_nomerges_store,
	306	};
	307
c7c22e4d JA	308	static struct queue_sysfs_entry queue_rq_affinity_entry = {
	309	.attr = {.name = "rq_affinity", .mode = S_IRUGO \| S_IWUSR },
	310	.show = queue_rq_affinity_show,
	311	.store = queue_rq_affinity_store,
	312	};
	313
bc58ba94 JA	314	static struct queue_sysfs_entry queue_iostats_entry = {
	315	.attr = {.name = "iostats", .mode = S_IRUGO \| S_IWUSR },
	316	.show = queue_iostats_show,
	317	.store = queue_iostats_store,
	318	};
	319
8324aa91 JA	320	static struct attribute *default_attrs[] = {
	321	&queue_requests_entry.attr,
	322	&queue_ra_entry.attr,
	323	&queue_max_hw_sectors_entry.attr,
	324	&queue_max_sectors_entry.attr,
	325	&queue_iosched_entry.attr,
e68b903c	326	&queue_hw_sector_size_entry.attr,
e1defc4f	327	&queue_logical_block_size_entry.attr,
c72758f3 MP	328	&queue_physical_block_size_entry.attr,
	329	&queue_io_min_entry.attr,
	330	&queue_io_opt_entry.attr,
1308835f	331	&queue_nonrot_entry.attr,
ac9fafa1	332	&queue_nomerges_entry.attr,
c7c22e4d	333	&queue_rq_affinity_entry.attr,
bc58ba94	334	&queue_iostats_entry.attr,
8324aa91 JA	335	NULL,
	336	};
	337
	338	#define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
	339
	340	static ssize_t
	341	queue_attr_show(struct kobject kobj, struct attribute attr, char *page)
	342	{
	343	struct queue_sysfs_entry *entry = to_queue(attr);
	344	struct request_queue *q =
	345	container_of(kobj, struct request_queue, kobj);
	346	ssize_t res;
	347
	348	if (!entry->show)
	349	return -EIO;
	350	mutex_lock(&q->sysfs_lock);
	351	if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
	352	mutex_unlock(&q->sysfs_lock);
	353	return -ENOENT;
	354	}
	355	res = entry->show(q, page);
	356	mutex_unlock(&q->sysfs_lock);
	357	return res;
	358	}
	359
	360	static ssize_t
	361	queue_attr_store(struct kobject kobj, struct attribute attr,
	362	const char *page, size_t length)
	363	{
	364	struct queue_sysfs_entry *entry = to_queue(attr);
6728cb0e	365	struct request_queue *q;
8324aa91 JA	366	ssize_t res;
	367
	368	if (!entry->store)
	369	return -EIO;
6728cb0e JA	370
6728cb0e JA	371	q = container_of(kobj, struct request_queue, kobj);
8324aa91 JA	372	mutex_lock(&q->sysfs_lock);
	373	if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
	374	mutex_unlock(&q->sysfs_lock);
	375	return -ENOENT;
	376	}
	377	res = entry->store(q, page, length);
	378	mutex_unlock(&q->sysfs_lock);
	379	return res;
	380	}
	381
	382	/**
	383	* blk_cleanup_queue: - release a &struct request_queue when it is no longer needed
	384	* @kobj: the kobj belonging of the request queue to be released
	385	*
	386	* Description:
	387	* blk_cleanup_queue is the pair to blk_init_queue() or
	388	* blk_queue_make_request(). It should be called when a request queue is
	389	* being released; typically when a block device is being de-registered.
	390	* Currently, its primary task it to free all the &struct request
	391	* structures that were allocated to the queue and the queue itself.
	392	*
	393	* Caveat:
	394	* Hopefully the low level driver will have finished any
	395	* outstanding requests first...
	396	**/
	397	static void blk_release_queue(struct kobject *kobj)
	398	{
	399	struct request_queue *q =
	400	container_of(kobj, struct request_queue, kobj);
	401	struct request_list *rl = &q->rq;
	402
	403	blk_sync_queue(q);
	404
	405	if (rl->rq_pool)
	406	mempool_destroy(rl->rq_pool);
	407
	408	if (q->queue_tags)
	409	__blk_queue_free_tags(q);
	410
	411	blk_trace_shutdown(q);
	412
	413	bdi_destroy(&q->backing_dev_info);
	414	kmem_cache_free(blk_requestq_cachep, q);
	415	}
	416
	417	static struct sysfs_ops queue_sysfs_ops = {
	418	.show = queue_attr_show,
	419	.store = queue_attr_store,
	420	};
	421
	422	struct kobj_type blk_queue_ktype = {
	423	.sysfs_ops = &queue_sysfs_ops,
	424	.default_attrs = default_attrs,
	425	.release = blk_release_queue,
	426	};
	427
	428	int blk_register_queue(struct gendisk *disk)
	429	{
	430	int ret;
1d54ad6d	431	struct device *dev = disk_to_dev(disk);
8324aa91 JA	432
	433	struct request_queue *q = disk->queue;
	434
fb199746	435	if (WARN_ON(!q))
8324aa91 JA	436	return -ENXIO;
8324aa91 JA	437
1d54ad6d LZ	438	ret = blk_trace_init_sysfs(dev);
	439	if (ret)
	440	return ret;
	441
c9059598	442	ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
8324aa91 JA	443	if (ret < 0)
	444	return ret;
	445
	446	kobject_uevent(&q->kobj, KOBJ_ADD);
	447
cd43e26f MP	448	if (!q->request_fn)
	449	return 0;
	450
8324aa91 JA	451	ret = elv_register_queue(q);
	452	if (ret) {
	453	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	454	kobject_del(&q->kobj);
48c0d4d4	455	blk_trace_remove_sysfs(disk_to_dev(disk));
8324aa91 JA	456	return ret;
	457	}
	458
	459	return 0;
	460	}
	461
	462	void blk_unregister_queue(struct gendisk *disk)
	463	{
	464	struct request_queue *q = disk->queue;
	465
fb199746 AM	466	if (WARN_ON(!q))
	467	return;
	468
48c0d4d4	469	if (q->request_fn)
8324aa91 JA	470	elv_unregister_queue(q);
8324aa91 JA	471
48c0d4d4 ZK	472	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	473	kobject_del(&q->kobj);
	474	blk_trace_remove_sysfs(disk_to_dev(disk));
	475	kobject_put(&disk_to_dev(disk)->kobj);
8324aa91	476	}