1
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>
14#include "blk.h"
15#include "blk-mq.h"
16#include "blk-mq-tag.h"
17
18static void blk_mq_sysfs_release(struct kobject *kobj)
19{
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
26static 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
31 kobject_put(&ctx->ctxs->kobj);
32}
33
34static 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);
38
39 cancel_delayed_work_sync(&hctx->run_work);
40
41 if (hctx->flags & BLK_MQ_F_BLOCKING)
42 cleanup_srcu_struct(hctx->srcu);
43 blk_free_flush_queue(hctx->fq);
44 sbitmap_free(&hctx->ctx_map);
45 free_cpumask_var(hctx->cpumask);
46 kfree(hctx->ctxs);
47 kfree(hctx);
48}
49
50struct blk_mq_ctx_sysfs_entry {
51 struct attribute attr;
52 ssize_t (*show)(struct blk_mq_ctx *, char *);
53 ssize_t (*store)(struct blk_mq_ctx *, const char *, size_t);
54};
55
56struct blk_mq_hw_ctx_sysfs_entry {
57 struct attribute attr;
58 ssize_t (*show)(struct blk_mq_hw_ctx *, char *);
59 ssize_t (*store)(struct blk_mq_hw_ctx *, const char *, size_t);
60};
61
62static ssize_t blk_mq_sysfs_show(struct kobject *kobj, struct attribute *attr,
63 char *page)
64{
65 struct blk_mq_ctx_sysfs_entry *entry;
66 struct blk_mq_ctx *ctx;
67 struct request_queue *q;
68 ssize_t res;
69
70 entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr);
71 ctx = container_of(kobj, struct blk_mq_ctx, kobj);
72 q = ctx->queue;
73
74 if (!entry->show)
75 return -EIO;
76
77 mutex_lock(&q->sysfs_lock);
78 res = entry->show(ctx, page);
79 mutex_unlock(&q->sysfs_lock);
80 return res;
81}
82
83static ssize_t blk_mq_sysfs_store(struct kobject *kobj, struct attribute *attr,
84 const char *page, size_t length)
85{
86 struct blk_mq_ctx_sysfs_entry *entry;
87 struct blk_mq_ctx *ctx;
88 struct request_queue *q;
89 ssize_t res;
90
91 entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr);
92 ctx = container_of(kobj, struct blk_mq_ctx, kobj);
93 q = ctx->queue;
94
95 if (!entry->store)
96 return -EIO;
97
98 mutex_lock(&q->sysfs_lock);
99 res = entry->store(ctx, page, length);
100 mutex_unlock(&q->sysfs_lock);
101 return res;
102}
103
104static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj,
105 struct attribute *attr, char *page)
106{
107 struct blk_mq_hw_ctx_sysfs_entry *entry;
108 struct blk_mq_hw_ctx *hctx;
109 struct request_queue *q;
110 ssize_t res;
111
112 entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
113 hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
114 q = hctx->queue;
115
116 if (!entry->show)
117 return -EIO;
118
119 mutex_lock(&q->sysfs_lock);
120 res = entry->show(hctx, page);
121 mutex_unlock(&q->sysfs_lock);
122 return res;
123}
124
125static ssize_t blk_mq_hw_sysfs_store(struct kobject *kobj,
126 struct attribute *attr, const char *page,
127 size_t length)
128{
129 struct blk_mq_hw_ctx_sysfs_entry *entry;
130 struct blk_mq_hw_ctx *hctx;
131 struct request_queue *q;
132 ssize_t res;
133
134 entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
135 hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
136 q = hctx->queue;
137
138 if (!entry->store)
139 return -EIO;
140
141 mutex_lock(&q->sysfs_lock);
142 res = entry->store(hctx, page, length);
143 mutex_unlock(&q->sysfs_lock);
144 return res;
145}
146
147static ssize_t blk_mq_hw_sysfs_nr_tags_show(struct blk_mq_hw_ctx *hctx,
148 char *page)
149{
150 return sprintf(page, "%u\n", hctx->tags->nr_tags);
151}
152
153static ssize_t blk_mq_hw_sysfs_nr_reserved_tags_show(struct blk_mq_hw_ctx *hctx,
154 char *page)
155{
156 return sprintf(page, "%u\n", hctx->tags->nr_reserved_tags);
157}
158
159static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
160{
161 const size_t size = PAGE_SIZE - 1;
162 unsigned int i, first = 1;
163 int ret = 0, pos = 0;
164
165 for_each_cpu(i, hctx->cpumask) {
166 if (first)
167 ret = snprintf(pos + page, size - pos, "%u", i);
168 else
169 ret = snprintf(pos + page, size - pos, ", %u", i);
170
171 if (ret >= size - pos)
172 break;
173
174 first = 0;
175 pos += ret;
176 }
177
178 ret = snprintf(pos + page, size + 1 - pos, "\n");
179 return pos + ret;
180}
181
182static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_tags = {
183 .attr = {.name = "nr_tags", .mode = 0444 },
184 .show = blk_mq_hw_sysfs_nr_tags_show,
185};
186static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_reserved_tags = {
187 .attr = {.name = "nr_reserved_tags", .mode = 0444 },
188 .show = blk_mq_hw_sysfs_nr_reserved_tags_show,
189};
190static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = {
191 .attr = {.name = "cpu_list", .mode = 0444 },
192 .show = blk_mq_hw_sysfs_cpus_show,
193};
194
195static struct attribute *default_hw_ctx_attrs[] = {
196 &blk_mq_hw_sysfs_nr_tags.attr,
197 &blk_mq_hw_sysfs_nr_reserved_tags.attr,
198 &blk_mq_hw_sysfs_cpus.attr,
199 NULL,
200};
201ATTRIBUTE_GROUPS(default_hw_ctx);
202
203static const struct sysfs_ops blk_mq_sysfs_ops = {
204 .show = blk_mq_sysfs_show,
205 .store = blk_mq_sysfs_store,
206};
207
208static const struct sysfs_ops blk_mq_hw_sysfs_ops = {
209 .show = blk_mq_hw_sysfs_show,
210 .store = blk_mq_hw_sysfs_store,
211};
212
213static struct kobj_type blk_mq_ktype = {
214 .sysfs_ops = &blk_mq_sysfs_ops,
215 .release = blk_mq_sysfs_release,
216};
217
218static struct kobj_type blk_mq_ctx_ktype = {
219 .sysfs_ops = &blk_mq_sysfs_ops,
220 .release = blk_mq_ctx_sysfs_release,
221};
222
223static struct kobj_type blk_mq_hw_ktype = {
224 .sysfs_ops = &blk_mq_hw_sysfs_ops,
225 .default_groups = default_hw_ctx_groups,
226 .release = blk_mq_hw_sysfs_release,
227};
228
229static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx)
230{
231 struct blk_mq_ctx *ctx;
232 int i;
233
234 if (!hctx->nr_ctx)
235 return;
236
237 hctx_for_each_ctx(hctx, ctx, i)
238 kobject_del(&ctx->kobj);
239
240 kobject_del(&hctx->kobj);
241}
242
243static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx)
244{
245 struct request_queue *q = hctx->queue;
246 struct blk_mq_ctx *ctx;
247 int i, ret;
248
249 if (!hctx->nr_ctx)
250 return 0;
251
252 ret = kobject_add(&hctx->kobj, q->mq_kobj, "%u", hctx->queue_num);
253 if (ret)
254 return ret;
255
256 hctx_for_each_ctx(hctx, ctx, i) {
257 ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
258 if (ret)
259 break;
260 }
261
262 return ret;
263}
264
265void blk_mq_unregister_dev(struct device *dev, struct request_queue *q)
266{
267 struct blk_mq_hw_ctx *hctx;
268 int i;
269
270 lockdep_assert_held(&q->sysfs_dir_lock);
271
272 queue_for_each_hw_ctx(q, hctx, i)
273 blk_mq_unregister_hctx(hctx);
274
275 kobject_uevent(q->mq_kobj, KOBJ_REMOVE);
276 kobject_del(q->mq_kobj);
277 kobject_put(&dev->kobj);
278
279 q->mq_sysfs_init_done = false;
280}
281
282void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx)
283{
284 kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
285}
286
287void blk_mq_sysfs_deinit(struct request_queue *q)
288{
289 struct blk_mq_ctx *ctx;
290 int cpu;
291
292 for_each_possible_cpu(cpu) {
293 ctx = per_cpu_ptr(q->queue_ctx, cpu);
294 kobject_put(&ctx->kobj);
295 }
296 kobject_put(q->mq_kobj);
297}
298
299void blk_mq_sysfs_init(struct request_queue *q)
300{
301 struct blk_mq_ctx *ctx;
302 int cpu;
303
304 kobject_init(q->mq_kobj, &blk_mq_ktype);
305
306 for_each_possible_cpu(cpu) {
307 ctx = per_cpu_ptr(q->queue_ctx, cpu);
308
309 kobject_get(q->mq_kobj);
310 kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
311 }
312}
313
314int __blk_mq_register_dev(struct device *dev, struct request_queue *q)
315{
316 struct blk_mq_hw_ctx *hctx;
317 int ret, i;
318
319 WARN_ON_ONCE(!q->kobj.parent);
320 lockdep_assert_held(&q->sysfs_dir_lock);
321
322 ret = kobject_add(q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
323 if (ret < 0)
324 goto out;
325
326 kobject_uevent(q->mq_kobj, KOBJ_ADD);
327
328 queue_for_each_hw_ctx(q, hctx, i) {
329 ret = blk_mq_register_hctx(hctx);
330 if (ret)
331 goto unreg;
332 }
333
334 q->mq_sysfs_init_done = true;
335
336out:
337 return ret;
338
339unreg:
340 while (--i >= 0)
341 blk_mq_unregister_hctx(q->queue_hw_ctx[i]);
342
343 kobject_uevent(q->mq_kobj, KOBJ_REMOVE);
344 kobject_del(q->mq_kobj);
345 kobject_put(&dev->kobj);
346 return ret;
347}
348
349void blk_mq_sysfs_unregister(struct request_queue *q)
350{
351 struct blk_mq_hw_ctx *hctx;
352 int i;
353
354 mutex_lock(&q->sysfs_dir_lock);
355 if (!q->mq_sysfs_init_done)
356 goto unlock;
357
358 queue_for_each_hw_ctx(q, hctx, i)
359 blk_mq_unregister_hctx(hctx);
360
361unlock:
362 mutex_unlock(&q->sysfs_dir_lock);
363}
364
365int blk_mq_sysfs_register(struct request_queue *q)
366{
367 struct blk_mq_hw_ctx *hctx;
368 int i, ret = 0;
369
370 mutex_lock(&q->sysfs_dir_lock);
371 if (!q->mq_sysfs_init_done)
372 goto unlock;
373
374 queue_for_each_hw_ctx(q, hctx, i) {
375 ret = blk_mq_register_hctx(hctx);
376 if (ret)
377 break;
378 }
379
380unlock:
381 mutex_unlock(&q->sysfs_dir_lock);
382
383 return ret;
384}
385
