1#include <linux/kernel.h>
2#include <linux/module.h>
3#include <linux/backing-dev.h>
4#include <linux/bio.h>
5#include <linux/blkdev.h>
6#include <linux/mm.h>
7#include <linux/init.h>
8#include <linux/slab.h>
9#include <linux/workqueue.h>
10#include <linux/smp.h>
11
12#include <linux/blk-mq.h>
13#include "blk-mq.h"
14#include "blk-mq-tag.h"
15
16static void blk_mq_sysfs_release(struct kobject *kobj)
17{
18}
19
20struct blk_mq_ctx_sysfs_entry {
21 struct attribute attr;
22 ssize_t (*show)(struct blk_mq_ctx *, char *);
23 ssize_t (*store)(struct blk_mq_ctx *, const char *, size_t);
24};
25
26struct blk_mq_hw_ctx_sysfs_entry {
27 struct attribute attr;
28 ssize_t (*show)(struct blk_mq_hw_ctx *, char *);
29 ssize_t (*store)(struct blk_mq_hw_ctx *, const char *, size_t);
30};
31
32static ssize_t blk_mq_sysfs_show(struct kobject *kobj, struct attribute *attr,
33 char *page)
34{
35 struct blk_mq_ctx_sysfs_entry *entry;
36 struct blk_mq_ctx *ctx;
37 struct request_queue *q;
38 ssize_t res;
39
40 entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr);
41 ctx = container_of(kobj, struct blk_mq_ctx, kobj);
42 q = ctx->queue;
43
44 if (!entry->show)
45 return -EIO;
46
47 res = -ENOENT;
48 mutex_lock(&q->sysfs_lock);
49 if (!blk_queue_dying(q))
50 res = entry->show(ctx, page);
51 mutex_unlock(&q->sysfs_lock);
52 return res;
53}
54
55static ssize_t blk_mq_sysfs_store(struct kobject *kobj, struct attribute *attr,
56 const char *page, size_t length)
57{
58 struct blk_mq_ctx_sysfs_entry *entry;
59 struct blk_mq_ctx *ctx;
60 struct request_queue *q;
61 ssize_t res;
62
63 entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr);
64 ctx = container_of(kobj, struct blk_mq_ctx, kobj);
65 q = ctx->queue;
66
67 if (!entry->store)
68 return -EIO;
69
70 res = -ENOENT;
71 mutex_lock(&q->sysfs_lock);
72 if (!blk_queue_dying(q))
73 res = entry->store(ctx, page, length);
74 mutex_unlock(&q->sysfs_lock);
75 return res;
76}
77
78static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj,
79 struct attribute *attr, char *page)
80{
81 struct blk_mq_hw_ctx_sysfs_entry *entry;
82 struct blk_mq_hw_ctx *hctx;
83 struct request_queue *q;
84 ssize_t res;
85
86 entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
87 hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
88 q = hctx->queue;
89
90 if (!entry->show)
91 return -EIO;
92
93 res = -ENOENT;
94 mutex_lock(&q->sysfs_lock);
95 if (!blk_queue_dying(q))
96 res = entry->show(hctx, page);
97 mutex_unlock(&q->sysfs_lock);
98 return res;
99}
100
101static ssize_t blk_mq_hw_sysfs_store(struct kobject *kobj,
102 struct attribute *attr, const char *page,
103 size_t length)
104{
105 struct blk_mq_hw_ctx_sysfs_entry *entry;
106 struct blk_mq_hw_ctx *hctx;
107 struct request_queue *q;
108 ssize_t res;
109
110 entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
111 hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
112 q = hctx->queue;
113
114 if (!entry->store)
115 return -EIO;
116
117 res = -ENOENT;
118 mutex_lock(&q->sysfs_lock);
119 if (!blk_queue_dying(q))
120 res = entry->store(hctx, page, length);
121 mutex_unlock(&q->sysfs_lock);
122 return res;
123}
124
125static ssize_t blk_mq_sysfs_dispatched_show(struct blk_mq_ctx *ctx, char *page)
126{
127 return sprintf(page, "%lu %lu\n", ctx->rq_dispatched[1],
128 ctx->rq_dispatched[0]);
129}
130
131static ssize_t blk_mq_sysfs_merged_show(struct blk_mq_ctx *ctx, char *page)
132{
133 return sprintf(page, "%lu\n", ctx->rq_merged);
134}
135
136static ssize_t blk_mq_sysfs_completed_show(struct blk_mq_ctx *ctx, char *page)
137{
138 return sprintf(page, "%lu %lu\n", ctx->rq_completed[1],
139 ctx->rq_completed[0]);
140}
141
142static ssize_t sysfs_list_show(char *page, struct list_head *list, char *msg)
143{
144 struct request *rq;
145 int len = snprintf(page, PAGE_SIZE - 1, "%s:\n", msg);
146
147 list_for_each_entry(rq, list, queuelist) {
148 const int rq_len = 2 * sizeof(rq) + 2;
149
150
151 if (PAGE_SIZE - 1 < len + rq_len) {
152
153 if (PAGE_SIZE - 1 < len + 5)
154 len -= rq_len;
155 len += snprintf(page + len, PAGE_SIZE - 1 - len,
156 "\t...\n");
157 break;
158 }
159 len += snprintf(page + len, PAGE_SIZE - 1 - len,
160 "\t%p\n", rq);
161 }
162
163 return len;
164}
165
166static ssize_t blk_mq_sysfs_rq_list_show(struct blk_mq_ctx *ctx, char *page)
167{
168 ssize_t ret;
169
170 spin_lock(&ctx->lock);
171 ret = sysfs_list_show(page, &ctx->rq_list, "CTX pending");
172 spin_unlock(&ctx->lock);
173
174 return ret;
175}
176
177static ssize_t blk_mq_hw_sysfs_poll_show(struct blk_mq_hw_ctx *hctx, char *page)
178{
179 return sprintf(page, "considered=%lu, invoked=%lu, success=%lu\n",
180 hctx->poll_considered, hctx->poll_invoked,
181 hctx->poll_success);
182}
183
184static ssize_t blk_mq_hw_sysfs_poll_store(struct blk_mq_hw_ctx *hctx,
185 const char *page, size_t size)
186{
187 hctx->poll_considered = hctx->poll_invoked = hctx->poll_success = 0;
188
189 return size;
190}
191
192static ssize_t blk_mq_hw_sysfs_queued_show(struct blk_mq_hw_ctx *hctx,
193 char *page)
194{
195 return sprintf(page, "%lu\n", hctx->queued);
196}
197
198static ssize_t blk_mq_hw_sysfs_run_show(struct blk_mq_hw_ctx *hctx, char *page)
199{
200 return sprintf(page, "%lu\n", hctx->run);
201}
202
203static ssize_t blk_mq_hw_sysfs_dispatched_show(struct blk_mq_hw_ctx *hctx,
204 char *page)
205{
206 char *start_page = page;
207 int i;
208
209 page += sprintf(page, "%8u\t%lu\n", 0U, hctx->dispatched[0]);
210
211 for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER - 1; i++) {
212 unsigned int d = 1U << (i - 1);
213
214 page += sprintf(page, "%8u\t%lu\n", d, hctx->dispatched[i]);
215 }
216
217 page += sprintf(page, "%8u+\t%lu\n", 1U << (i - 1),
218 hctx->dispatched[i]);
219 return page - start_page;
220}
221
222static ssize_t blk_mq_hw_sysfs_rq_list_show(struct blk_mq_hw_ctx *hctx,
223 char *page)
224{
225 ssize_t ret;
226
227 spin_lock(&hctx->lock);
228 ret = sysfs_list_show(page, &hctx->dispatch, "HCTX pending");
229 spin_unlock(&hctx->lock);
230
231 return ret;
232}
233
234static ssize_t blk_mq_hw_sysfs_tags_show(struct blk_mq_hw_ctx *hctx, char *page)
235{
236 return blk_mq_tag_sysfs_show(hctx->tags, page);
237}
238
239static ssize_t blk_mq_hw_sysfs_active_show(struct blk_mq_hw_ctx *hctx, char *page)
240{
241 return sprintf(page, "%u\n", atomic_read(&hctx->nr_active));
242}
243
244static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
245{
246 unsigned int i, first = 1;
247 ssize_t ret = 0;
248
249 for_each_cpu(i, hctx->cpumask) {
250 if (first)
251 ret += sprintf(ret + page, "%u", i);
252 else
253 ret += sprintf(ret + page, ", %u", i);
254
255 first = 0;
256 }
257
258 ret += sprintf(ret + page, "\n");
259 return ret;
260}
261
262static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_dispatched = {
263 .attr = {.name = "dispatched", .mode = S_IRUGO },
264 .show = blk_mq_sysfs_dispatched_show,
265};
266static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_merged = {
267 .attr = {.name = "merged", .mode = S_IRUGO },
268 .show = blk_mq_sysfs_merged_show,
269};
270static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_completed = {
271 .attr = {.name = "completed", .mode = S_IRUGO },
272 .show = blk_mq_sysfs_completed_show,
273};
274static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_rq_list = {
275 .attr = {.name = "rq_list", .mode = S_IRUGO },
276 .show = blk_mq_sysfs_rq_list_show,
277};
278
279static struct attribute *default_ctx_attrs[] = {
280 &blk_mq_sysfs_dispatched.attr,
281 &blk_mq_sysfs_merged.attr,
282 &blk_mq_sysfs_completed.attr,
283 &blk_mq_sysfs_rq_list.attr,
284 NULL,
285};
286
287static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_queued = {
288 .attr = {.name = "queued", .mode = S_IRUGO },
289 .show = blk_mq_hw_sysfs_queued_show,
290};
291static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_run = {
292 .attr = {.name = "run", .mode = S_IRUGO },
293 .show = blk_mq_hw_sysfs_run_show,
294};
295static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_dispatched = {
296 .attr = {.name = "dispatched", .mode = S_IRUGO },
297 .show = blk_mq_hw_sysfs_dispatched_show,
298};
299static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_active = {
300 .attr = {.name = "active", .mode = S_IRUGO },
301 .show = blk_mq_hw_sysfs_active_show,
302};
303static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_pending = {
304 .attr = {.name = "pending", .mode = S_IRUGO },
305 .show = blk_mq_hw_sysfs_rq_list_show,
306};
307static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_tags = {
308 .attr = {.name = "tags", .mode = S_IRUGO },
309 .show = blk_mq_hw_sysfs_tags_show,
310};
311static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = {
312 .attr = {.name = "cpu_list", .mode = S_IRUGO },
313 .show = blk_mq_hw_sysfs_cpus_show,
314};
315static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_poll = {
316 .attr = {.name = "io_poll", .mode = S_IWUSR | S_IRUGO },
317 .show = blk_mq_hw_sysfs_poll_show,
318 .store = blk_mq_hw_sysfs_poll_store,
319};
320
321static struct attribute *default_hw_ctx_attrs[] = {
322 &blk_mq_hw_sysfs_queued.attr,
323 &blk_mq_hw_sysfs_run.attr,
324 &blk_mq_hw_sysfs_dispatched.attr,
325 &blk_mq_hw_sysfs_pending.attr,
326 &blk_mq_hw_sysfs_tags.attr,
327 &blk_mq_hw_sysfs_cpus.attr,
328 &blk_mq_hw_sysfs_active.attr,
329 &blk_mq_hw_sysfs_poll.attr,
330 NULL,
331};
332
333static const struct sysfs_ops blk_mq_sysfs_ops = {
334 .show = blk_mq_sysfs_show,
335 .store = blk_mq_sysfs_store,
336};
337
338static const struct sysfs_ops blk_mq_hw_sysfs_ops = {
339 .show = blk_mq_hw_sysfs_show,
340 .store = blk_mq_hw_sysfs_store,
341};
342
343static struct kobj_type blk_mq_ktype = {
344 .sysfs_ops = &blk_mq_sysfs_ops,
345 .release = blk_mq_sysfs_release,
346};
347
348static struct kobj_type blk_mq_ctx_ktype = {
349 .sysfs_ops = &blk_mq_sysfs_ops,
350 .default_attrs = default_ctx_attrs,
351 .release = blk_mq_sysfs_release,
352};
353
354static struct kobj_type blk_mq_hw_ktype = {
355 .sysfs_ops = &blk_mq_hw_sysfs_ops,
356 .default_attrs = default_hw_ctx_attrs,
357 .release = blk_mq_sysfs_release,
358};
359
360static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx)
361{
362 struct blk_mq_ctx *ctx;
363 int i;
364
365 if (!hctx->nr_ctx)
366 return;
367
368 hctx_for_each_ctx(hctx, ctx, i)
369 kobject_del(&ctx->kobj);
370
371 kobject_del(&hctx->kobj);
372}
373
374static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx)
375{
376 struct request_queue *q = hctx->queue;
377 struct blk_mq_ctx *ctx;
378 int i, ret;
379
380 if (!hctx->nr_ctx)
381 return 0;
382
383 ret = kobject_add(&hctx->kobj, &q->mq_kobj, "%u", hctx->queue_num);
384 if (ret)
385 return ret;
386
387 hctx_for_each_ctx(hctx, ctx, i) {
388 ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
389 if (ret)
390 break;
391 }
392
393 return ret;
394}
395
396static void __blk_mq_unregister_dev(struct device *dev, struct request_queue *q)
397{
398 struct blk_mq_hw_ctx *hctx;
399 struct blk_mq_ctx *ctx;
400 int i, j;
401
402 queue_for_each_hw_ctx(q, hctx, i) {
403 blk_mq_unregister_hctx(hctx);
404
405 hctx_for_each_ctx(hctx, ctx, j)
406 kobject_put(&ctx->kobj);
407
408 kobject_put(&hctx->kobj);
409 }
410
411 kobject_uevent(&q->mq_kobj, KOBJ_REMOVE);
412 kobject_del(&q->mq_kobj);
413 kobject_put(&q->mq_kobj);
414
415 kobject_put(&dev->kobj);
416
417 q->mq_sysfs_init_done = false;
418}
419
420void blk_mq_unregister_dev(struct device *dev, struct request_queue *q)
421{
422 blk_mq_disable_hotplug();
423 __blk_mq_unregister_dev(dev, q);
424 blk_mq_enable_hotplug();
425}
426
427void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx)
428{
429 kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
430}
431
432static void blk_mq_sysfs_init(struct request_queue *q)
433{
434 struct blk_mq_ctx *ctx;
435 int cpu;
436
437 kobject_init(&q->mq_kobj, &blk_mq_ktype);
438
439 for_each_possible_cpu(cpu) {
440 ctx = per_cpu_ptr(q->queue_ctx, cpu);
441 kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
442 }
443}
444
445int blk_mq_register_dev(struct device *dev, struct request_queue *q)
446{
447 struct blk_mq_hw_ctx *hctx;
448 int ret, i;
449
450 blk_mq_disable_hotplug();
451
452 blk_mq_sysfs_init(q);
453
454 ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
455 if (ret < 0)
456 goto out;
457
458 kobject_uevent(&q->mq_kobj, KOBJ_ADD);
459
460 queue_for_each_hw_ctx(q, hctx, i) {
461 ret = blk_mq_register_hctx(hctx);
462 if (ret)
463 break;
464 }
465
466 if (ret)
467 __blk_mq_unregister_dev(dev, q);
468 else
469 q->mq_sysfs_init_done = true;
470out:
471 blk_mq_enable_hotplug();
472
473 return ret;
474}
475EXPORT_SYMBOL_GPL(blk_mq_register_dev);
476
477void blk_mq_sysfs_unregister(struct request_queue *q)
478{
479 struct blk_mq_hw_ctx *hctx;
480 int i;
481
482 if (!q->mq_sysfs_init_done)
483 return;
484
485 queue_for_each_hw_ctx(q, hctx, i)
486 blk_mq_unregister_hctx(hctx);
487}
488
489int blk_mq_sysfs_register(struct request_queue *q)
490{
491 struct blk_mq_hw_ctx *hctx;
492 int i, ret = 0;
493
494 if (!q->mq_sysfs_init_done)
495 return ret;
496
497 queue_for_each_hw_ctx(q, hctx, i) {
498 ret = blk_mq_register_hctx(hctx);
499 if (ret)
500 break;
501 }
502
503 return ret;
504}
505
