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

// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/backing-dev.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/smp.h>

#include <linux/blk-mq.h>
#include "blk.h"
#include "blk-mq.h"
#include "blk-mq-tag.h"

static void blk_mq_sysfs_release(struct kobject *kobj)
{
	struct blk_mq_ctxs *ctxs = container_of(kobj, struct blk_mq_ctxs, kobj);

	free_percpu(ctxs->queue_ctx);
	kfree(ctxs);
}

static void blk_mq_ctx_sysfs_release(struct kobject *kobj)
{
	struct blk_mq_ctx *ctx = container_of(kobj, struct blk_mq_ctx, kobj);

	/* ctx->ctxs won't be released until all ctx are freed */
	kobject_put(&ctx->ctxs->kobj);
}

static void blk_mq_hw_sysfs_release(struct kobject *kobj)
{
	struct blk_mq_hw_ctx *hctx = container_of(kobj, struct blk_mq_hw_ctx,
						  kobj);

	blk_free_flush_queue(hctx->fq);
	sbitmap_free(&hctx->ctx_map);
	free_cpumask_var(hctx->cpumask);
	kfree(hctx->ctxs);
	kfree(hctx);
}

struct blk_mq_hw_ctx_sysfs_entry {
	struct attribute attr;
	ssize_t (*show)(struct blk_mq_hw_ctx *, char *);
};

static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj,
				    struct attribute *attr, char *page)
{
	struct blk_mq_hw_ctx_sysfs_entry *entry;
	struct blk_mq_hw_ctx *hctx;
	struct request_queue *q;
	ssize_t res;

	entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
	hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
	q = hctx->queue;

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

	mutex_lock(&q->sysfs_lock);
	res = entry->show(hctx, page);
	mutex_unlock(&q->sysfs_lock);
	return res;
}

static ssize_t blk_mq_hw_sysfs_nr_tags_show(struct blk_mq_hw_ctx *hctx,
					    char *page)
{
	return sprintf(page, "%u\n", hctx->tags->nr_tags);
}

static ssize_t blk_mq_hw_sysfs_nr_reserved_tags_show(struct blk_mq_hw_ctx *hctx,
						     char *page)
{
	return sprintf(page, "%u\n", hctx->tags->nr_reserved_tags);
}

static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
{
	const size_t size = PAGE_SIZE - 1;
	unsigned int i, first = 1;
	int ret = 0, pos = 0;

	for_each_cpu(i, hctx->cpumask) {
		if (first)
			ret = snprintf(pos + page, size - pos, "%u", i);
		else
			ret = snprintf(pos + page, size - pos, ", %u", i);

		if (ret >= size - pos)
			break;

		first = 0;
		pos += ret;
	}

	ret = snprintf(pos + page, size + 1 - pos, "\n");
	return pos + ret;
}

static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_tags = {
	.attr = {.name = "nr_tags", .mode = 0444 },
	.show = blk_mq_hw_sysfs_nr_tags_show,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_reserved_tags = {
	.attr = {.name = "nr_reserved_tags", .mode = 0444 },
	.show = blk_mq_hw_sysfs_nr_reserved_tags_show,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = {
	.attr = {.name = "cpu_list", .mode = 0444 },
	.show = blk_mq_hw_sysfs_cpus_show,
};

static struct attribute *default_hw_ctx_attrs[] = {
	&blk_mq_hw_sysfs_nr_tags.attr,
	&blk_mq_hw_sysfs_nr_reserved_tags.attr,
	&blk_mq_hw_sysfs_cpus.attr,
	NULL,
};
ATTRIBUTE_GROUPS(default_hw_ctx);

static const struct sysfs_ops blk_mq_hw_sysfs_ops = {
	.show	= blk_mq_hw_sysfs_show,
};

static const struct kobj_type blk_mq_ktype = {
	.release	= blk_mq_sysfs_release,
};

static const struct kobj_type blk_mq_ctx_ktype = {
	.release	= blk_mq_ctx_sysfs_release,
};

static const struct kobj_type blk_mq_hw_ktype = {
	.sysfs_ops	= &blk_mq_hw_sysfs_ops,
	.default_groups = default_hw_ctx_groups,
	.release	= blk_mq_hw_sysfs_release,
};

static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx)
{
	struct blk_mq_ctx *ctx;
	int i;

	if (!hctx->nr_ctx)
		return;

	hctx_for_each_ctx(hctx, ctx, i)
		kobject_del(&ctx->kobj);

	kobject_del(&hctx->kobj);
}

static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx)
{
	struct request_queue *q = hctx->queue;
	struct blk_mq_ctx *ctx;
	int i, j, ret;

	if (!hctx->nr_ctx)
		return 0;

	ret = kobject_add(&hctx->kobj, q->mq_kobj, "%u", hctx->queue_num);
	if (ret)
		return ret;

	hctx_for_each_ctx(hctx, ctx, i) {
		ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
		if (ret)
			goto out;
	}

	return 0;
out:
	hctx_for_each_ctx(hctx, ctx, j) {
		if (j < i)
			kobject_del(&ctx->kobj);
	}
	kobject_del(&hctx->kobj);
	return ret;
}

void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx)
{
	kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
}

void blk_mq_sysfs_deinit(struct request_queue *q)
{
	struct blk_mq_ctx *ctx;
	int cpu;

	for_each_possible_cpu(cpu) {
		ctx = per_cpu_ptr(q->queue_ctx, cpu);
		kobject_put(&ctx->kobj);
	}
	kobject_put(q->mq_kobj);
}

void blk_mq_sysfs_init(struct request_queue *q)
{
	struct blk_mq_ctx *ctx;
	int cpu;

	kobject_init(q->mq_kobj, &blk_mq_ktype);

	for_each_possible_cpu(cpu) {
		ctx = per_cpu_ptr(q->queue_ctx, cpu);

		kobject_get(q->mq_kobj);
		kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
	}
}

int blk_mq_sysfs_register(struct gendisk *disk)
{
	struct request_queue *q = disk->queue;
	struct blk_mq_hw_ctx *hctx;
	unsigned long i, j;
	int ret;

	lockdep_assert_held(&q->sysfs_dir_lock);

	ret = kobject_add(q->mq_kobj, &disk_to_dev(disk)->kobj, "mq");
	if (ret < 0)
		goto out;

	kobject_uevent(q->mq_kobj, KOBJ_ADD);

	queue_for_each_hw_ctx(q, hctx, i) {
		ret = blk_mq_register_hctx(hctx);
		if (ret)
			goto unreg;
	}

	q->mq_sysfs_init_done = true;

out:
	return ret;

unreg:
	queue_for_each_hw_ctx(q, hctx, j) {
		if (j < i)
			blk_mq_unregister_hctx(hctx);
	}

	kobject_uevent(q->mq_kobj, KOBJ_REMOVE);
	kobject_del(q->mq_kobj);
	return ret;
}

void blk_mq_sysfs_unregister(struct gendisk *disk)
{
	struct request_queue *q = disk->queue;
	struct blk_mq_hw_ctx *hctx;
	unsigned long i;

	lockdep_assert_held(&q->sysfs_dir_lock);

	queue_for_each_hw_ctx(q, hctx, i)
		blk_mq_unregister_hctx(hctx);

	kobject_uevent(q->mq_kobj, KOBJ_REMOVE);
	kobject_del(q->mq_kobj);

	q->mq_sysfs_init_done = false;
}

void blk_mq_sysfs_unregister_hctxs(struct request_queue *q)
{
	struct blk_mq_hw_ctx *hctx;
	unsigned long i;

	mutex_lock(&q->sysfs_dir_lock);
	if (!q->mq_sysfs_init_done)
		goto unlock;

	queue_for_each_hw_ctx(q, hctx, i)
		blk_mq_unregister_hctx(hctx);

unlock:
	mutex_unlock(&q->sysfs_dir_lock);
}

int blk_mq_sysfs_register_hctxs(struct request_queue *q)
{
	struct blk_mq_hw_ctx *hctx;
	unsigned long i;
	int ret = 0;

	mutex_lock(&q->sysfs_dir_lock);
	if (!q->mq_sysfs_init_done)
		goto unlock;

	queue_for_each_hw_ctx(q, hctx, i) {
		ret = blk_mq_register_hctx(hctx);
		if (ret)
			break;
	}

unlock:
	mutex_unlock(&q->sysfs_dir_lock);

	return ret;
}
Commit	Line	Data
3dcf60bc	1	// SPDX-License-Identifier: GPL-2.0
320ae51f JA	2	#include <linux/kernel.h>
	3	#include <linux/module.h>
	4	#include <linux/backing-dev.h>
	5	#include <linux/bio.h>
	6	#include <linux/blkdev.h>
	7	#include <linux/mm.h>
	8	#include <linux/init.h>
	9	#include <linux/slab.h>
	10	#include <linux/workqueue.h>
	11	#include <linux/smp.h>
	12
	13	#include <linux/blk-mq.h>
c7e2d94b	14	#include "blk.h"
320ae51f JA	15	#include "blk-mq.h"
	16	#include "blk-mq-tag.h"
	17
	18	static void blk_mq_sysfs_release(struct kobject *kobj)
	19	{
1db4909e ML	20	struct blk_mq_ctxs *ctxs = container_of(kobj, struct blk_mq_ctxs, kobj);
	21
	22	free_percpu(ctxs->queue_ctx);
	23	kfree(ctxs);
	24	}
	25
	26	static void blk_mq_ctx_sysfs_release(struct kobject *kobj)
	27	{
	28	struct blk_mq_ctx *ctx = container_of(kobj, struct blk_mq_ctx, kobj);
	29
	30	/* ctx->ctxs won't be released until all ctx are freed */
	31	kobject_put(&ctx->ctxs->kobj);
320ae51f JA	32	}
320ae51f JA	33
6c8b232e ML	34	static void blk_mq_hw_sysfs_release(struct kobject *kobj)
	35	{
	36	struct blk_mq_hw_ctx *hctx = container_of(kobj, struct blk_mq_hw_ctx,
	37	kobj);
c7e2d94b	38
c7e2d94b ML	39	blk_free_flush_queue(hctx->fq);
c7e2d94b ML	40	sbitmap_free(&hctx->ctx_map);
01388df3	41	free_cpumask_var(hctx->cpumask);
6c8b232e ML	42	kfree(hctx->ctxs);
	43	kfree(hctx);
	44	}
	45
320ae51f JA	46	struct blk_mq_hw_ctx_sysfs_entry {
	47	struct attribute attr;
	48	ssize_t (show)(struct blk_mq_hw_ctx , char *);
320ae51f JA	49	};
320ae51f JA	50
320ae51f JA	51	static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj,
	52	struct attribute attr, char page)
	53	{
	54	struct blk_mq_hw_ctx_sysfs_entry *entry;
	55	struct blk_mq_hw_ctx *hctx;
	56	struct request_queue *q;
	57	ssize_t res;
	58
	59	entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
	60	hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
	61	q = hctx->queue;
	62
	63	if (!entry->show)
	64	return -EIO;
	65
320ae51f	66	mutex_lock(&q->sysfs_lock);
bae85c15	67	res = entry->show(hctx, page);
320ae51f JA	68	mutex_unlock(&q->sysfs_lock);
	69	return res;
	70	}
	71
d96b37c0 OS	72	static ssize_t blk_mq_hw_sysfs_nr_tags_show(struct blk_mq_hw_ctx *hctx,
d96b37c0 OS	73	char *page)
bd166ef1	74	{
d96b37c0	75	return sprintf(page, "%u\n", hctx->tags->nr_tags);
bd166ef1 JA	76	}
bd166ef1 JA	77
d96b37c0 OS	78	static ssize_t blk_mq_hw_sysfs_nr_reserved_tags_show(struct blk_mq_hw_ctx *hctx,
d96b37c0 OS	79	char *page)
320ae51f	80	{
d96b37c0	81	return sprintf(page, "%u\n", hctx->tags->nr_reserved_tags);
320ae51f JA	82	}
320ae51f JA	83
676141e4 JA	84	static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx hctx, char page)
676141e4 JA	85	{
8962842c	86	const size_t size = PAGE_SIZE - 1;
cb2da43e	87	unsigned int i, first = 1;
8962842c	88	int ret = 0, pos = 0;
676141e4	89
cb2da43e	90	for_each_cpu(i, hctx->cpumask) {
676141e4	91	if (first)
8962842c	92	ret = snprintf(pos + page, size - pos, "%u", i);
676141e4	93	else
8962842c ML	94	ret = snprintf(pos + page, size - pos, ", %u", i);
	95
	96	if (ret >= size - pos)
	97	break;
676141e4 JA	98
676141e4 JA	99	first = 0;
8962842c	100	pos += ret;
676141e4 JA	101	}
676141e4 JA	102
d2c9be89	103	ret = snprintf(pos + page, size + 1 - pos, "\n");
8962842c	104	return pos + ret;
676141e4 JA	105	}
676141e4 JA	106
d96b37c0	107	static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_tags = {
5657a819	108	.attr = {.name = "nr_tags", .mode = 0444 },
d96b37c0 OS	109	.show = blk_mq_hw_sysfs_nr_tags_show,
	110	};
	111	static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_reserved_tags = {
5657a819	112	.attr = {.name = "nr_reserved_tags", .mode = 0444 },
d96b37c0 OS	113	.show = blk_mq_hw_sysfs_nr_reserved_tags_show,
d96b37c0 OS	114	};
676141e4	115	static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = {
5657a819	116	.attr = {.name = "cpu_list", .mode = 0444 },
676141e4 JA	117	.show = blk_mq_hw_sysfs_cpus_show,
676141e4 JA	118	};
320ae51f JA	119
320ae51f JA	120	static struct attribute *default_hw_ctx_attrs[] = {
d96b37c0 OS	121	&blk_mq_hw_sysfs_nr_tags.attr,
d96b37c0 OS	122	&blk_mq_hw_sysfs_nr_reserved_tags.attr,
676141e4	123	&blk_mq_hw_sysfs_cpus.attr,
320ae51f JA	124	NULL,
320ae51f JA	125	};
800f5aa1	126	ATTRIBUTE_GROUPS(default_hw_ctx);
320ae51f	127
320ae51f JA	128	static const struct sysfs_ops blk_mq_hw_sysfs_ops = {
320ae51f JA	129	.show = blk_mq_hw_sysfs_show,
320ae51f JA	130	};
320ae51f JA	131
5f622417	132	static const struct kobj_type blk_mq_ktype = {
320ae51f JA	133	.release = blk_mq_sysfs_release,
	134	};
	135
5f622417	136	static const struct kobj_type blk_mq_ctx_ktype = {
1db4909e	137	.release = blk_mq_ctx_sysfs_release,
320ae51f JA	138	};
320ae51f JA	139
5f622417	140	static const struct kobj_type blk_mq_hw_ktype = {
320ae51f	141	.sysfs_ops = &blk_mq_hw_sysfs_ops,
800f5aa1	142	.default_groups = default_hw_ctx_groups,
6c8b232e	143	.release = blk_mq_hw_sysfs_release,
320ae51f JA	144	};
320ae51f JA	145
ee3c5db0	146	static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx)
67aec14c JA	147	{
	148	struct blk_mq_ctx *ctx;
	149	int i;
	150
4593fdbe	151	if (!hctx->nr_ctx)
67aec14c JA	152	return;
	153
	154	hctx_for_each_ctx(hctx, ctx, i)
	155	kobject_del(&ctx->kobj);
	156
	157	kobject_del(&hctx->kobj);
	158	}
	159
ee3c5db0	160	static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx)
67aec14c JA	161	{
	162	struct request_queue *q = hctx->queue;
	163	struct blk_mq_ctx *ctx;
4b7a21c5	164	int i, j, ret;
67aec14c	165
4593fdbe	166	if (!hctx->nr_ctx)
67aec14c JA	167	return 0;
67aec14c JA	168
1db4909e	169	ret = kobject_add(&hctx->kobj, q->mq_kobj, "%u", hctx->queue_num);
67aec14c JA	170	if (ret)
	171	return ret;
	172
	173	hctx_for_each_ctx(hctx, ctx, i) {
	174	ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
	175	if (ret)
4b7a21c5	176	goto out;
67aec14c JA	177	}
67aec14c JA	178
4b7a21c5 YB	179	return 0;
	180	out:
	181	hctx_for_each_ctx(hctx, ctx, j) {
	182	if (j < i)
	183	kobject_del(&ctx->kobj);
	184	}
	185	kobject_del(&hctx->kobj);
67aec14c JA	186	return ret;
	187	}
	188
868f2f0b KB	189	void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx)
	190	{
	191	kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
	192	}
	193
7ea5fe31 ML	194	void blk_mq_sysfs_deinit(struct request_queue *q)
	195	{
	196	struct blk_mq_ctx *ctx;
	197	int cpu;
	198
	199	for_each_possible_cpu(cpu) {
	200	ctx = per_cpu_ptr(q->queue_ctx, cpu);
	201	kobject_put(&ctx->kobj);
	202	}
1db4909e	203	kobject_put(q->mq_kobj);
7ea5fe31 ML	204	}
7ea5fe31 ML	205
737f98cf	206	void blk_mq_sysfs_init(struct request_queue *q)
67aec14c	207	{
67aec14c	208	struct blk_mq_ctx *ctx;
897bb0c7	209	int cpu;
67aec14c	210
1db4909e	211	kobject_init(q->mq_kobj, &blk_mq_ktype);
67aec14c	212
897bb0c7 TG	213	for_each_possible_cpu(cpu) {
897bb0c7 TG	214	ctx = per_cpu_ptr(q->queue_ctx, cpu);
1db4909e ML	215
1db4909e ML	216	kobject_get(q->mq_kobj);
06a41a99	217	kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
897bb0c7	218	}
67aec14c JA	219	}
67aec14c JA	220
8682b92e	221	int blk_mq_sysfs_register(struct gendisk *disk)
320ae51f	222	{
8682b92e	223	struct request_queue *q = disk->queue;
320ae51f	224	struct blk_mq_hw_ctx *hctx;
4f481208 ML	225	unsigned long i, j;
4f481208 ML	226	int ret;
320ae51f	227
cecf5d87	228	lockdep_assert_held(&q->sysfs_dir_lock);
4593fdbe	229
8682b92e	230	ret = kobject_add(q->mq_kobj, &disk_to_dev(disk)->kobj, "mq");
320ae51f	231	if (ret < 0)
4593fdbe	232	goto out;
320ae51f	233
1db4909e	234	kobject_uevent(q->mq_kobj, KOBJ_ADD);
320ae51f JA	235
320ae51f JA	236	queue_for_each_hw_ctx(q, hctx, i) {
67aec14c	237	ret = blk_mq_register_hctx(hctx);
320ae51f	238	if (ret)
f05d1ba7	239	goto unreg;
320ae51f JA	240	}
320ae51f JA	241
f05d1ba7	242	q->mq_sysfs_init_done = true;
2d0364c8	243
4593fdbe	244	out:
2d0364c8	245	return ret;
f05d1ba7 BVA	246
f05d1ba7 BVA	247	unreg:
4f481208 ML	248	queue_for_each_hw_ctx(q, hctx, j) {
	249	if (j < i)
	250	blk_mq_unregister_hctx(hctx);
	251	}
f05d1ba7	252
1db4909e ML	253	kobject_uevent(q->mq_kobj, KOBJ_REMOVE);
1db4909e ML	254	kobject_del(q->mq_kobj);
f05d1ba7	255	return ret;
2d0364c8 BVA	256	}
2d0364c8 BVA	257
8682b92e CH	258	void blk_mq_sysfs_unregister(struct gendisk *disk)
	259	{
	260	struct request_queue *q = disk->queue;
	261	struct blk_mq_hw_ctx *hctx;
	262	unsigned long i;
	263
	264	lockdep_assert_held(&q->sysfs_dir_lock);
	265
	266	queue_for_each_hw_ctx(q, hctx, i)
	267	blk_mq_unregister_hctx(hctx);
	268
	269	kobject_uevent(q->mq_kobj, KOBJ_REMOVE);
	270	kobject_del(q->mq_kobj);
	271
	272	q->mq_sysfs_init_done = false;
	273	}
	274
eaa870f9	275	void blk_mq_sysfs_unregister_hctxs(struct request_queue *q)
67aec14c JA	276	{
67aec14c JA	277	struct blk_mq_hw_ctx *hctx;
4f481208	278	unsigned long i;
67aec14c	279
cecf5d87	280	mutex_lock(&q->sysfs_dir_lock);
4593fdbe	281	if (!q->mq_sysfs_init_done)
2d0364c8	282	goto unlock;
4593fdbe	283
67aec14c JA	284	queue_for_each_hw_ctx(q, hctx, i)
67aec14c JA	285	blk_mq_unregister_hctx(hctx);
2d0364c8 BVA	286
2d0364c8 BVA	287	unlock:
cecf5d87	288	mutex_unlock(&q->sysfs_dir_lock);
67aec14c JA	289	}
67aec14c JA	290
eaa870f9	291	int blk_mq_sysfs_register_hctxs(struct request_queue *q)
67aec14c JA	292	{
67aec14c JA	293	struct blk_mq_hw_ctx *hctx;
4f481208 ML	294	unsigned long i;
4f481208 ML	295	int ret = 0;
67aec14c	296
cecf5d87	297	mutex_lock(&q->sysfs_dir_lock);
4593fdbe	298	if (!q->mq_sysfs_init_done)
2d0364c8	299	goto unlock;
4593fdbe	300
67aec14c JA	301	queue_for_each_hw_ctx(q, hctx, i) {
	302	ret = blk_mq_register_hctx(hctx);
	303	if (ret)
	304	break;
	305	}
	306
2d0364c8	307	unlock:
cecf5d87	308	mutex_unlock(&q->sysfs_dir_lock);
2d0364c8	309
67aec14c JA	310	return ret;
67aec14c JA	311	}