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, "invoked=%lu, success=%lu\n", hctx->poll_invoked, hctx->poll_success);
180}
181
182static ssize_t blk_mq_hw_sysfs_queued_show(struct blk_mq_hw_ctx *hctx,
183 char *page)
184{
185 return sprintf(page, "%lu\n", hctx->queued);
186}
187
188static ssize_t blk_mq_hw_sysfs_run_show(struct blk_mq_hw_ctx *hctx, char *page)
189{
190 return sprintf(page, "%lu\n", hctx->run);
191}
192
193static ssize_t blk_mq_hw_sysfs_dispatched_show(struct blk_mq_hw_ctx *hctx,
194 char *page)
195{
196 char *start_page = page;
197 int i;
198
199 page += sprintf(page, "%8u\t%lu\n", 0U, hctx->dispatched[0]);
200
201 for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER; i++) {
202 unsigned long d = 1U << (i - 1);
203
204 page += sprintf(page, "%8lu\t%lu\n", d, hctx->dispatched[i]);
205 }
206
207 return page - start_page;
208}
209
210static ssize_t blk_mq_hw_sysfs_rq_list_show(struct blk_mq_hw_ctx *hctx,
211 char *page)
212{
213 ssize_t ret;
214
215 spin_lock(&hctx->lock);
216 ret = sysfs_list_show(page, &hctx->dispatch, "HCTX pending");
217 spin_unlock(&hctx->lock);
218
219 return ret;
220}
221
222static ssize_t blk_mq_hw_sysfs_tags_show(struct blk_mq_hw_ctx *hctx, char *page)
223{
224 return blk_mq_tag_sysfs_show(hctx->tags, page);
225}
226
227static ssize_t blk_mq_hw_sysfs_active_show(struct blk_mq_hw_ctx *hctx, char *page)
228{
229 return sprintf(page, "%u\n", atomic_read(&hctx->nr_active));
230}
231
232static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
233{
234 unsigned int i, first = 1;
235 ssize_t ret = 0;
236
237 for_each_cpu(i, hctx->cpumask) {
238 if (first)
239 ret += sprintf(ret + page, "%u", i);
240 else
241 ret += sprintf(ret + page, ", %u", i);
242
243 first = 0;
244 }
245
246 ret += sprintf(ret + page, "\n");
247 return ret;
248}
249
250static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_dispatched = {
251 .attr = {.name = "dispatched", .mode = S_IRUGO },
252 .show = blk_mq_sysfs_dispatched_show,
253};
254static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_merged = {
255 .attr = {.name = "merged", .mode = S_IRUGO },
256 .show = blk_mq_sysfs_merged_show,
257};
258static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_completed = {
259 .attr = {.name = "completed", .mode = S_IRUGO },
260 .show = blk_mq_sysfs_completed_show,
261};
262static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_rq_list = {
263 .attr = {.name = "rq_list", .mode = S_IRUGO },
264 .show = blk_mq_sysfs_rq_list_show,
265};
266
267static struct attribute *default_ctx_attrs[] = {
268 &blk_mq_sysfs_dispatched.attr,
269 &blk_mq_sysfs_merged.attr,
270 &blk_mq_sysfs_completed.attr,
271 &blk_mq_sysfs_rq_list.attr,
272 NULL,
273};
274
275static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_queued = {
276 .attr = {.name = "queued", .mode = S_IRUGO },
277 .show = blk_mq_hw_sysfs_queued_show,
278};
279static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_run = {
280 .attr = {.name = "run", .mode = S_IRUGO },
281 .show = blk_mq_hw_sysfs_run_show,
282};
283static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_dispatched = {
284 .attr = {.name = "dispatched", .mode = S_IRUGO },
285 .show = blk_mq_hw_sysfs_dispatched_show,
286};
287static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_active = {
288 .attr = {.name = "active", .mode = S_IRUGO },
289 .show = blk_mq_hw_sysfs_active_show,
290};
291static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_pending = {
292 .attr = {.name = "pending", .mode = S_IRUGO },
293 .show = blk_mq_hw_sysfs_rq_list_show,
294};
295static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_tags = {
296 .attr = {.name = "tags", .mode = S_IRUGO },
297 .show = blk_mq_hw_sysfs_tags_show,
298};
299static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = {
300 .attr = {.name = "cpu_list", .mode = S_IRUGO },
301 .show = blk_mq_hw_sysfs_cpus_show,
302};
303static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_poll = {
304 .attr = {.name = "io_poll", .mode = S_IRUGO },
305 .show = blk_mq_hw_sysfs_poll_show,
306};
307
308static struct attribute *default_hw_ctx_attrs[] = {
309 &blk_mq_hw_sysfs_queued.attr,
310 &blk_mq_hw_sysfs_run.attr,
311 &blk_mq_hw_sysfs_dispatched.attr,
312 &blk_mq_hw_sysfs_pending.attr,
313 &blk_mq_hw_sysfs_tags.attr,
314 &blk_mq_hw_sysfs_cpus.attr,
315 &blk_mq_hw_sysfs_active.attr,
316 &blk_mq_hw_sysfs_poll.attr,
317 NULL,
318};
319
320static const struct sysfs_ops blk_mq_sysfs_ops = {
321 .show = blk_mq_sysfs_show,
322 .store = blk_mq_sysfs_store,
323};
324
325static const struct sysfs_ops blk_mq_hw_sysfs_ops = {
326 .show = blk_mq_hw_sysfs_show,
327 .store = blk_mq_hw_sysfs_store,
328};
329
330static struct kobj_type blk_mq_ktype = {
331 .sysfs_ops = &blk_mq_sysfs_ops,
332 .release = blk_mq_sysfs_release,
333};
334
335static struct kobj_type blk_mq_ctx_ktype = {
336 .sysfs_ops = &blk_mq_sysfs_ops,
337 .default_attrs = default_ctx_attrs,
338 .release = blk_mq_sysfs_release,
339};
340
341static struct kobj_type blk_mq_hw_ktype = {
342 .sysfs_ops = &blk_mq_hw_sysfs_ops,
343 .default_attrs = default_hw_ctx_attrs,
344 .release = blk_mq_sysfs_release,
345};
346
347static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx)
348{
349 struct blk_mq_ctx *ctx;
350 int i;
351
352 if (!hctx->nr_ctx)
353 return;
354
355 hctx_for_each_ctx(hctx, ctx, i)
356 kobject_del(&ctx->kobj);
357
358 kobject_del(&hctx->kobj);
359}
360
361static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx)
362{
363 struct request_queue *q = hctx->queue;
364 struct blk_mq_ctx *ctx;
365 int i, ret;
366
367 if (!hctx->nr_ctx)
368 return 0;
369
370 ret = kobject_add(&hctx->kobj, &q->mq_kobj, "%u", hctx->queue_num);
371 if (ret)
372 return ret;
373
374 hctx_for_each_ctx(hctx, ctx, i) {
375 ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
376 if (ret)
377 break;
378 }
379
380 return ret;
381}
382
383void blk_mq_unregister_disk(struct gendisk *disk)
384{
385 struct request_queue *q = disk->queue;
386 struct blk_mq_hw_ctx *hctx;
387 struct blk_mq_ctx *ctx;
388 int i, j;
389
390 blk_mq_disable_hotplug();
391
392 queue_for_each_hw_ctx(q, hctx, i) {
393 blk_mq_unregister_hctx(hctx);
394
395 hctx_for_each_ctx(hctx, ctx, j)
396 kobject_put(&ctx->kobj);
397
398 kobject_put(&hctx->kobj);
399 }
400
401 kobject_uevent(&q->mq_kobj, KOBJ_REMOVE);
402 kobject_del(&q->mq_kobj);
403 kobject_put(&q->mq_kobj);
404
405 kobject_put(&disk_to_dev(disk)->kobj);
406
407 q->mq_sysfs_init_done = false;
408 blk_mq_enable_hotplug();
409}
410
411static void blk_mq_sysfs_init(struct request_queue *q)
412{
413 struct blk_mq_hw_ctx *hctx;
414 struct blk_mq_ctx *ctx;
415 int i;
416
417 kobject_init(&q->mq_kobj, &blk_mq_ktype);
418
419 queue_for_each_hw_ctx(q, hctx, i)
420 kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
421
422 queue_for_each_ctx(q, ctx, i)
423 kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
424}
425
426int blk_mq_register_disk(struct gendisk *disk)
427{
428 struct device *dev = disk_to_dev(disk);
429 struct request_queue *q = disk->queue;
430 struct blk_mq_hw_ctx *hctx;
431 int ret, i;
432
433 blk_mq_disable_hotplug();
434
435 blk_mq_sysfs_init(q);
436
437 ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
438 if (ret < 0)
439 goto out;
440
441 kobject_uevent(&q->mq_kobj, KOBJ_ADD);
442
443 queue_for_each_hw_ctx(q, hctx, i) {
444 ret = blk_mq_register_hctx(hctx);
445 if (ret)
446 break;
447 }
448
449 if (ret)
450 blk_mq_unregister_disk(disk);
451 else
452 q->mq_sysfs_init_done = true;
453out:
454 blk_mq_enable_hotplug();
455
456 return ret;
457}
458EXPORT_SYMBOL_GPL(blk_mq_register_disk);
459
460void blk_mq_sysfs_unregister(struct request_queue *q)
461{
462 struct blk_mq_hw_ctx *hctx;
463 int i;
464
465 if (!q->mq_sysfs_init_done)
466 return;
467
468 queue_for_each_hw_ctx(q, hctx, i)
469 blk_mq_unregister_hctx(hctx);
470}
471
472int blk_mq_sysfs_register(struct request_queue *q)
473{
474 struct blk_mq_hw_ctx *hctx;
475 int i, ret = 0;
476
477 if (!q->mq_sysfs_init_done)
478 return ret;
479
480 queue_for_each_hw_ctx(q, hctx, i) {
481 ret = blk_mq_register_hctx(hctx);
482 if (ret)
483 break;
484 }
485
486 return ret;
487}
488
