[deliverable/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_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 queue_var_show(q->limits.max_discard_sectors << 9, page);
}

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_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) << 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);

	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);

	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_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_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_discard_granularity_entry.attr,
	&queue_discard_max_entry.attr,
	&queue_discard_zeroes_data_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 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;

	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
	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
	19	queue_var_show(unsigned long var, char *page)
	20	{
	21	return sprintf(page, "%lu\n", var);
	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;
	43	int ret;
	44
	45	if (!q->request_fn)
	46	return -EINVAL;
	47
	48	ret = queue_var_store(&nr, page, count);
	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
	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]);
	71	}
	72
	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]);
	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	{
	85	unsigned long ra_kb = q->backing_dev_info.ra_pages <<
	86	(PAGE_CACHE_SHIFT - 10);
	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
	97	q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);
	98
	99	return ret;
	100	}
	101
	102	static ssize_t queue_max_sectors_show(struct request_queue q, char page)
	103	{
	104	int max_sectors_kb = queue_max_sectors(q) >> 1;
	105
	106	return queue_var_show(max_sectors_kb, (page));
	107	}
	108
	109	static ssize_t queue_logical_block_size_show(struct request_queue q, char page)
	110	{
	111	return queue_var_show(queue_logical_block_size(q), page);
	112	}
	113
	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);
	127	}
	128
	129	static ssize_t queue_discard_granularity_show(struct request_queue q, char page)
	130	{
	131	return queue_var_show(q->limits.discard_granularity, page);
	132	}
	133
	134	static ssize_t queue_discard_max_show(struct request_queue q, char page)
	135	{
	136	return queue_var_show(q->limits.max_discard_sectors << 9, page);
	137	}
	138
	139	static ssize_t queue_discard_zeroes_data_show(struct request_queue q, char page)
	140	{
	141	return queue_var_show(queue_discard_zeroes_data(q), page);
	142	}
	143
	144	static ssize_t
	145	queue_max_sectors_store(struct request_queue q, const char page, size_t count)
	146	{
	147	unsigned long max_sectors_kb,
	148	max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
	149	page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
	150	ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
	151
	152	if (max_sectors_kb > max_hw_sectors_kb \|\| max_sectors_kb < page_kb)
	153	return -EINVAL;
	154
	155	spin_lock_irq(q->queue_lock);
	156	q->limits.max_sectors = max_sectors_kb << 1;
	157	spin_unlock_irq(q->queue_lock);
	158
	159	return ret;
	160	}
	161
	162	static ssize_t queue_max_hw_sectors_show(struct request_queue q, char page)
	163	{
	164	int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
	165
	166	return queue_var_show(max_hw_sectors_kb, (page));
	167	}
	168
	169	static ssize_t queue_nonrot_show(struct request_queue q, char page)
	170	{
	171	return queue_var_show(!blk_queue_nonrot(q), page);
	172	}
	173
	174	static ssize_t queue_nonrot_store(struct request_queue q, const char page,
	175	size_t count)
	176	{
	177	unsigned long nm;
	178	ssize_t ret = queue_var_store(&nm, page, count);
	179
	180	spin_lock_irq(q->queue_lock);
	181	if (nm)
	182	queue_flag_clear(QUEUE_FLAG_NONROT, q);
	183	else
	184	queue_flag_set(QUEUE_FLAG_NONROT, q);
	185	spin_unlock_irq(q->queue_lock);
	186
	187	return ret;
	188	}
	189
	190	static ssize_t queue_nomerges_show(struct request_queue q, char page)
	191	{
	192	return queue_var_show((blk_queue_nomerges(q) << 1) \|
	193	blk_queue_noxmerges(q), page);
	194	}
	195
	196	static ssize_t queue_nomerges_store(struct request_queue q, const char page,
	197	size_t count)
	198	{
	199	unsigned long nm;
	200	ssize_t ret = queue_var_store(&nm, page, count);
	201
	202	spin_lock_irq(q->queue_lock);
	203	queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
	204	queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
	205	if (nm == 2)
	206	queue_flag_set(QUEUE_FLAG_NOMERGES, q);
	207	else if (nm)
	208	queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
	209	spin_unlock_irq(q->queue_lock);
	210
	211	return ret;
	212	}
	213
	214	static ssize_t queue_rq_affinity_show(struct request_queue q, char page)
	215	{
	216	bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
	217
	218	return queue_var_show(set, page);
	219	}
	220
	221	static ssize_t
	222	queue_rq_affinity_store(struct request_queue q, const char page, size_t count)
	223	{
	224	ssize_t ret = -EINVAL;
	225	#if defined(CONFIG_USE_GENERIC_SMP_HELPERS)
	226	unsigned long val;
	227
	228	ret = queue_var_store(&val, page, count);
	229	spin_lock_irq(q->queue_lock);
	230	if (val)
	231	queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
	232	else
	233	queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
	234	spin_unlock_irq(q->queue_lock);
	235	#endif
	236	return ret;
	237	}
	238
	239	static ssize_t queue_iostats_show(struct request_queue q, char page)
	240	{
	241	return queue_var_show(blk_queue_io_stat(q), page);
	242	}
	243
	244	static ssize_t queue_iostats_store(struct request_queue q, const char page,
	245	size_t count)
	246	{
	247	unsigned long stats;
	248	ssize_t ret = queue_var_store(&stats, page, count);
	249
	250	spin_lock_irq(q->queue_lock);
	251	if (stats)
	252	queue_flag_set(QUEUE_FLAG_IO_STAT, q);
	253	else
	254	queue_flag_clear(QUEUE_FLAG_IO_STAT, q);
	255	spin_unlock_irq(q->queue_lock);
	256
	257	return ret;
	258	}
	259
	260	static struct queue_sysfs_entry queue_requests_entry = {
	261	.attr = {.name = "nr_requests", .mode = S_IRUGO \| S_IWUSR },
	262	.show = queue_requests_show,
	263	.store = queue_requests_store,
	264	};
	265
	266	static struct queue_sysfs_entry queue_ra_entry = {
	267	.attr = {.name = "read_ahead_kb", .mode = S_IRUGO \| S_IWUSR },
	268	.show = queue_ra_show,
	269	.store = queue_ra_store,
	270	};
	271
	272	static struct queue_sysfs_entry queue_max_sectors_entry = {
	273	.attr = {.name = "max_sectors_kb", .mode = S_IRUGO \| S_IWUSR },
	274	.show = queue_max_sectors_show,
	275	.store = queue_max_sectors_store,
	276	};
	277
	278	static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
	279	.attr = {.name = "max_hw_sectors_kb", .mode = S_IRUGO },
	280	.show = queue_max_hw_sectors_show,
	281	};
	282
	283	static struct queue_sysfs_entry queue_iosched_entry = {
	284	.attr = {.name = "scheduler", .mode = S_IRUGO \| S_IWUSR },
	285	.show = elv_iosched_show,
	286	.store = elv_iosched_store,
	287	};
	288
	289	static struct queue_sysfs_entry queue_hw_sector_size_entry = {
	290	.attr = {.name = "hw_sector_size", .mode = S_IRUGO },
	291	.show = queue_logical_block_size_show,
	292	};
	293
	294	static struct queue_sysfs_entry queue_logical_block_size_entry = {
	295	.attr = {.name = "logical_block_size", .mode = S_IRUGO },
	296	.show = queue_logical_block_size_show,
	297	};
	298
	299	static struct queue_sysfs_entry queue_physical_block_size_entry = {
	300	.attr = {.name = "physical_block_size", .mode = S_IRUGO },
	301	.show = queue_physical_block_size_show,
	302	};
	303
	304	static struct queue_sysfs_entry queue_io_min_entry = {
	305	.attr = {.name = "minimum_io_size", .mode = S_IRUGO },
	306	.show = queue_io_min_show,
	307	};
	308
	309	static struct queue_sysfs_entry queue_io_opt_entry = {
	310	.attr = {.name = "optimal_io_size", .mode = S_IRUGO },
	311	.show = queue_io_opt_show,
	312	};
	313
	314	static struct queue_sysfs_entry queue_discard_granularity_entry = {
	315	.attr = {.name = "discard_granularity", .mode = S_IRUGO },
	316	.show = queue_discard_granularity_show,
	317	};
	318
	319	static struct queue_sysfs_entry queue_discard_max_entry = {
	320	.attr = {.name = "discard_max_bytes", .mode = S_IRUGO },
	321	.show = queue_discard_max_show,
	322	};
	323
	324	static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
	325	.attr = {.name = "discard_zeroes_data", .mode = S_IRUGO },
	326	.show = queue_discard_zeroes_data_show,
	327	};
	328
	329	static struct queue_sysfs_entry queue_nonrot_entry = {
	330	.attr = {.name = "rotational", .mode = S_IRUGO \| S_IWUSR },
	331	.show = queue_nonrot_show,
	332	.store = queue_nonrot_store,
	333	};
	334
	335	static struct queue_sysfs_entry queue_nomerges_entry = {
	336	.attr = {.name = "nomerges", .mode = S_IRUGO \| S_IWUSR },
	337	.show = queue_nomerges_show,
	338	.store = queue_nomerges_store,
	339	};
	340
	341	static struct queue_sysfs_entry queue_rq_affinity_entry = {
	342	.attr = {.name = "rq_affinity", .mode = S_IRUGO \| S_IWUSR },
	343	.show = queue_rq_affinity_show,
	344	.store = queue_rq_affinity_store,
	345	};
	346
	347	static struct queue_sysfs_entry queue_iostats_entry = {
	348	.attr = {.name = "iostats", .mode = S_IRUGO \| S_IWUSR },
	349	.show = queue_iostats_show,
	350	.store = queue_iostats_store,
	351	};
	352
	353	static struct attribute *default_attrs[] = {
	354	&queue_requests_entry.attr,
	355	&queue_ra_entry.attr,
	356	&queue_max_hw_sectors_entry.attr,
	357	&queue_max_sectors_entry.attr,
	358	&queue_iosched_entry.attr,
	359	&queue_hw_sector_size_entry.attr,
	360	&queue_logical_block_size_entry.attr,
	361	&queue_physical_block_size_entry.attr,
	362	&queue_io_min_entry.attr,
	363	&queue_io_opt_entry.attr,
	364	&queue_discard_granularity_entry.attr,
	365	&queue_discard_max_entry.attr,
	366	&queue_discard_zeroes_data_entry.attr,
	367	&queue_nonrot_entry.attr,
	368	&queue_nomerges_entry.attr,
	369	&queue_rq_affinity_entry.attr,
	370	&queue_iostats_entry.attr,
	371	NULL,
	372	};
	373
	374	#define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
	375
	376	static ssize_t
	377	queue_attr_show(struct kobject kobj, struct attribute attr, char *page)
	378	{
	379	struct queue_sysfs_entry *entry = to_queue(attr);
	380	struct request_queue *q =
	381	container_of(kobj, struct request_queue, kobj);
	382	ssize_t res;
	383
	384	if (!entry->show)
	385	return -EIO;
	386	mutex_lock(&q->sysfs_lock);
	387	if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
	388	mutex_unlock(&q->sysfs_lock);
	389	return -ENOENT;
	390	}
	391	res = entry->show(q, page);
	392	mutex_unlock(&q->sysfs_lock);
	393	return res;
	394	}
	395
	396	static ssize_t
	397	queue_attr_store(struct kobject kobj, struct attribute attr,
	398	const char *page, size_t length)
	399	{
	400	struct queue_sysfs_entry *entry = to_queue(attr);
	401	struct request_queue *q;
	402	ssize_t res;
	403
	404	if (!entry->store)
	405	return -EIO;
	406
	407	q = container_of(kobj, struct request_queue, kobj);
	408	mutex_lock(&q->sysfs_lock);
	409	if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
	410	mutex_unlock(&q->sysfs_lock);
	411	return -ENOENT;
	412	}
	413	res = entry->store(q, page, length);
	414	mutex_unlock(&q->sysfs_lock);
	415	return res;
	416	}
	417
	418	/**
	419	* blk_cleanup_queue: - release a &struct request_queue when it is no longer needed
	420	* @kobj: the kobj belonging of the request queue to be released
	421	*
	422	* Description:
	423	* blk_cleanup_queue is the pair to blk_init_queue() or
	424	* blk_queue_make_request(). It should be called when a request queue is
	425	* being released; typically when a block device is being de-registered.
	426	* Currently, its primary task it to free all the &struct request
	427	* structures that were allocated to the queue and the queue itself.
	428	*
	429	* Caveat:
	430	* Hopefully the low level driver will have finished any
	431	* outstanding requests first...
	432	**/
	433	static void blk_release_queue(struct kobject *kobj)
	434	{
	435	struct request_queue *q =
	436	container_of(kobj, struct request_queue, kobj);
	437	struct request_list *rl = &q->rq;
	438
	439	blk_sync_queue(q);
	440
	441	if (rl->rq_pool)
	442	mempool_destroy(rl->rq_pool);
	443
	444	if (q->queue_tags)
	445	__blk_queue_free_tags(q);
	446
	447	blk_trace_shutdown(q);
	448
	449	bdi_destroy(&q->backing_dev_info);
	450	kmem_cache_free(blk_requestq_cachep, q);
	451	}
	452
	453	static const struct sysfs_ops queue_sysfs_ops = {
	454	.show = queue_attr_show,
	455	.store = queue_attr_store,
	456	};
	457
	458	struct kobj_type blk_queue_ktype = {
	459	.sysfs_ops = &queue_sysfs_ops,
	460	.default_attrs = default_attrs,
	461	.release = blk_release_queue,
	462	};
	463
	464	int blk_register_queue(struct gendisk *disk)
	465	{
	466	int ret;
	467	struct device *dev = disk_to_dev(disk);
	468
	469	struct request_queue *q = disk->queue;
	470
	471	if (WARN_ON(!q))
	472	return -ENXIO;
	473
	474	ret = blk_trace_init_sysfs(dev);
	475	if (ret)
	476	return ret;
	477
	478	ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
	479	if (ret < 0)
	480	return ret;
	481
	482	kobject_uevent(&q->kobj, KOBJ_ADD);
	483
	484	if (!q->request_fn)
	485	return 0;
	486
	487	ret = elv_register_queue(q);
	488	if (ret) {
	489	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	490	kobject_del(&q->kobj);
	491	blk_trace_remove_sysfs(disk_to_dev(disk));
	492	return ret;
	493	}
	494
	495	return 0;
	496	}
	497
	498	void blk_unregister_queue(struct gendisk *disk)
	499	{
	500	struct request_queue *q = disk->queue;
	501
	502	if (WARN_ON(!q))
	503	return;
	504
	505	if (q->request_fn)
	506	elv_unregister_queue(q);
	507
	508	kobject_uevent(&q->kobj, KOBJ_REMOVE);
	509	kobject_del(&q->kobj);
	510	blk_trace_remove_sysfs(disk_to_dev(disk));
	511	kobject_put(&disk_to_dev(disk)->kobj);
	512	}