1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kernel.h>
3 #include <linux/module.h>
4 #include <linux/backing-dev.h>
6 #include <linux/blkdev.h>
8 #include <linux/init.h>
9 #include <linux/slab.h>
10 #include <linux/workqueue.h>
11 #include <linux/smp.h>
13 #include <linux/blk-mq.h>
16 #include "blk-mq-tag.h"
18 static void blk_mq_sysfs_release(struct kobject *kobj)
20 struct blk_mq_ctxs *ctxs = container_of(kobj, struct blk_mq_ctxs, kobj);
22 free_percpu(ctxs->queue_ctx);
26 static void blk_mq_ctx_sysfs_release(struct kobject *kobj)
28 struct blk_mq_ctx *ctx = container_of(kobj, struct blk_mq_ctx, kobj);
30 /* ctx->ctxs won't be released until all ctx are freed */
31 kobject_put(&ctx->ctxs->kobj);
34 static void blk_mq_hw_sysfs_release(struct kobject *kobj)
36 struct blk_mq_hw_ctx *hctx = container_of(kobj, struct blk_mq_hw_ctx,
39 if (hctx->flags & BLK_MQ_F_BLOCKING)
40 cleanup_srcu_struct(hctx->srcu);
41 blk_free_flush_queue(hctx->fq);
42 sbitmap_free(&hctx->ctx_map);
43 free_cpumask_var(hctx->cpumask);
48 struct blk_mq_ctx_sysfs_entry {
49 struct attribute attr;
50 ssize_t (*show)(struct blk_mq_ctx *, char *);
51 ssize_t (*store)(struct blk_mq_ctx *, const char *, size_t);
54 struct blk_mq_hw_ctx_sysfs_entry {
55 struct attribute attr;
56 ssize_t (*show)(struct blk_mq_hw_ctx *, char *);
57 ssize_t (*store)(struct blk_mq_hw_ctx *, const char *, size_t);
60 static ssize_t blk_mq_sysfs_show(struct kobject *kobj, struct attribute *attr,
63 struct blk_mq_ctx_sysfs_entry *entry;
64 struct blk_mq_ctx *ctx;
65 struct request_queue *q;
68 entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr);
69 ctx = container_of(kobj, struct blk_mq_ctx, kobj);
75 mutex_lock(&q->sysfs_lock);
76 res = entry->show(ctx, page);
77 mutex_unlock(&q->sysfs_lock);
81 static ssize_t blk_mq_sysfs_store(struct kobject *kobj, struct attribute *attr,
82 const char *page, size_t length)
84 struct blk_mq_ctx_sysfs_entry *entry;
85 struct blk_mq_ctx *ctx;
86 struct request_queue *q;
89 entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr);
90 ctx = container_of(kobj, struct blk_mq_ctx, kobj);
96 mutex_lock(&q->sysfs_lock);
97 res = entry->store(ctx, page, length);
98 mutex_unlock(&q->sysfs_lock);
102 static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj,
103 struct attribute *attr, char *page)
105 struct blk_mq_hw_ctx_sysfs_entry *entry;
106 struct blk_mq_hw_ctx *hctx;
107 struct request_queue *q;
110 entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
111 hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
117 mutex_lock(&q->sysfs_lock);
118 res = entry->show(hctx, page);
119 mutex_unlock(&q->sysfs_lock);
123 static ssize_t blk_mq_hw_sysfs_store(struct kobject *kobj,
124 struct attribute *attr, const char *page,
127 struct blk_mq_hw_ctx_sysfs_entry *entry;
128 struct blk_mq_hw_ctx *hctx;
129 struct request_queue *q;
132 entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
133 hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
139 mutex_lock(&q->sysfs_lock);
140 res = entry->store(hctx, page, length);
141 mutex_unlock(&q->sysfs_lock);
145 static ssize_t blk_mq_hw_sysfs_nr_tags_show(struct blk_mq_hw_ctx *hctx,
148 return sprintf(page, "%u\n", hctx->tags->nr_tags);
151 static ssize_t blk_mq_hw_sysfs_nr_reserved_tags_show(struct blk_mq_hw_ctx *hctx,
154 return sprintf(page, "%u\n", hctx->tags->nr_reserved_tags);
157 static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
159 const size_t size = PAGE_SIZE - 1;
160 unsigned int i, first = 1;
161 int ret = 0, pos = 0;
163 for_each_cpu(i, hctx->cpumask) {
165 ret = snprintf(pos + page, size - pos, "%u", i);
167 ret = snprintf(pos + page, size - pos, ", %u", i);
169 if (ret >= size - pos)
176 ret = snprintf(pos + page, size + 1 - pos, "\n");
180 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_tags = {
181 .attr = {.name = "nr_tags", .mode = 0444 },
182 .show = blk_mq_hw_sysfs_nr_tags_show,
184 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_reserved_tags = {
185 .attr = {.name = "nr_reserved_tags", .mode = 0444 },
186 .show = blk_mq_hw_sysfs_nr_reserved_tags_show,
188 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = {
189 .attr = {.name = "cpu_list", .mode = 0444 },
190 .show = blk_mq_hw_sysfs_cpus_show,
193 static struct attribute *default_hw_ctx_attrs[] = {
194 &blk_mq_hw_sysfs_nr_tags.attr,
195 &blk_mq_hw_sysfs_nr_reserved_tags.attr,
196 &blk_mq_hw_sysfs_cpus.attr,
199 ATTRIBUTE_GROUPS(default_hw_ctx);
201 static const struct sysfs_ops blk_mq_sysfs_ops = {
202 .show = blk_mq_sysfs_show,
203 .store = blk_mq_sysfs_store,
206 static const struct sysfs_ops blk_mq_hw_sysfs_ops = {
207 .show = blk_mq_hw_sysfs_show,
208 .store = blk_mq_hw_sysfs_store,
211 static struct kobj_type blk_mq_ktype = {
212 .sysfs_ops = &blk_mq_sysfs_ops,
213 .release = blk_mq_sysfs_release,
216 static struct kobj_type blk_mq_ctx_ktype = {
217 .sysfs_ops = &blk_mq_sysfs_ops,
218 .release = blk_mq_ctx_sysfs_release,
221 static struct kobj_type blk_mq_hw_ktype = {
222 .sysfs_ops = &blk_mq_hw_sysfs_ops,
223 .default_groups = default_hw_ctx_groups,
224 .release = blk_mq_hw_sysfs_release,
227 static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx)
229 struct blk_mq_ctx *ctx;
235 hctx_for_each_ctx(hctx, ctx, i)
236 kobject_del(&ctx->kobj);
238 kobject_del(&hctx->kobj);
241 static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx)
243 struct request_queue *q = hctx->queue;
244 struct blk_mq_ctx *ctx;
250 ret = kobject_add(&hctx->kobj, q->mq_kobj, "%u", hctx->queue_num);
254 hctx_for_each_ctx(hctx, ctx, i) {
255 ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
262 hctx_for_each_ctx(hctx, ctx, j) {
264 kobject_del(&ctx->kobj);
266 kobject_del(&hctx->kobj);
270 void blk_mq_unregister_dev(struct device *dev, struct request_queue *q)
272 struct blk_mq_hw_ctx *hctx;
275 lockdep_assert_held(&q->sysfs_dir_lock);
277 queue_for_each_hw_ctx(q, hctx, i)
278 blk_mq_unregister_hctx(hctx);
280 kobject_uevent(q->mq_kobj, KOBJ_REMOVE);
281 kobject_del(q->mq_kobj);
282 kobject_put(&dev->kobj);
284 q->mq_sysfs_init_done = false;
287 void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx)
289 kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
292 void blk_mq_sysfs_deinit(struct request_queue *q)
294 struct blk_mq_ctx *ctx;
297 for_each_possible_cpu(cpu) {
298 ctx = per_cpu_ptr(q->queue_ctx, cpu);
299 kobject_put(&ctx->kobj);
301 kobject_put(q->mq_kobj);
304 void blk_mq_sysfs_init(struct request_queue *q)
306 struct blk_mq_ctx *ctx;
309 kobject_init(q->mq_kobj, &blk_mq_ktype);
311 for_each_possible_cpu(cpu) {
312 ctx = per_cpu_ptr(q->queue_ctx, cpu);
314 kobject_get(q->mq_kobj);
315 kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
319 int __blk_mq_register_dev(struct device *dev, struct request_queue *q)
321 struct blk_mq_hw_ctx *hctx;
324 WARN_ON_ONCE(!q->kobj.parent);
325 lockdep_assert_held(&q->sysfs_dir_lock);
327 ret = kobject_add(q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
331 kobject_uevent(q->mq_kobj, KOBJ_ADD);
333 queue_for_each_hw_ctx(q, hctx, i) {
334 ret = blk_mq_register_hctx(hctx);
339 q->mq_sysfs_init_done = true;
346 blk_mq_unregister_hctx(q->queue_hw_ctx[i]);
348 kobject_uevent(q->mq_kobj, KOBJ_REMOVE);
349 kobject_del(q->mq_kobj);
350 kobject_put(&dev->kobj);
354 void blk_mq_sysfs_unregister(struct request_queue *q)
356 struct blk_mq_hw_ctx *hctx;
359 mutex_lock(&q->sysfs_dir_lock);
360 if (!q->mq_sysfs_init_done)
363 queue_for_each_hw_ctx(q, hctx, i)
364 blk_mq_unregister_hctx(hctx);
367 mutex_unlock(&q->sysfs_dir_lock);
370 int blk_mq_sysfs_register(struct request_queue *q)
372 struct blk_mq_hw_ctx *hctx;
375 mutex_lock(&q->sysfs_dir_lock);
376 if (!q->mq_sysfs_init_done)
379 queue_for_each_hw_ctx(q, hctx, i) {
380 ret = blk_mq_register_hctx(hctx);
386 mutex_unlock(&q->sysfs_dir_lock);