1/*
2 * Copyright (C) 2017 Facebook
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program. If not, see <https://www.gnu.org/licenses/>.
15 */
16
17#include <linux/kernel.h>
18#include <linux/blkdev.h>
19#include <linux/debugfs.h>
20
21#include <linux/blk-mq.h>
22#include "blk.h"
23#include "blk-mq.h"
24#include "blk-mq-debugfs.h"
25#include "blk-mq-tag.h"
26#include "blk-rq-qos.h"
27
28static void print_stat(struct seq_file *m, struct blk_rq_stat *stat)
29{
30 if (stat->nr_samples) {
31 seq_printf(m, "samples=%d, mean=%lld, min=%llu, max=%llu",
32 stat->nr_samples, stat->mean, stat->min, stat->max);
33 } else {
34 seq_puts(m, "samples=0");
35 }
36}
37
38static int queue_poll_stat_show(void *data, struct seq_file *m)
39{
40 struct request_queue *q = data;
41 int bucket;
42
43 for (bucket = 0; bucket < BLK_MQ_POLL_STATS_BKTS/2; bucket++) {
44 seq_printf(m, "read (%d Bytes): ", 1 << (9+bucket));
45 print_stat(m, &q->poll_stat[2*bucket]);
46 seq_puts(m, "\n");
47
48 seq_printf(m, "write (%d Bytes): ", 1 << (9+bucket));
49 print_stat(m, &q->poll_stat[2*bucket+1]);
50 seq_puts(m, "\n");
51 }
52 return 0;
53}
54
55static void *queue_requeue_list_start(struct seq_file *m, loff_t *pos)
56 __acquires(&q->requeue_lock)
57{
58 struct request_queue *q = m->private;
59
60 spin_lock_irq(&q->requeue_lock);
61 return seq_list_start(&q->requeue_list, *pos);
62}
63
64static void *queue_requeue_list_next(struct seq_file *m, void *v, loff_t *pos)
65{
66 struct request_queue *q = m->private;
67
68 return seq_list_next(v, &q->requeue_list, pos);
69}
70
71static void queue_requeue_list_stop(struct seq_file *m, void *v)
72 __releases(&q->requeue_lock)
73{
74 struct request_queue *q = m->private;
75
76 spin_unlock_irq(&q->requeue_lock);
77}
78
79static const struct seq_operations queue_requeue_list_seq_ops = {
80 .start = queue_requeue_list_start,
81 .next = queue_requeue_list_next,
82 .stop = queue_requeue_list_stop,
83 .show = blk_mq_debugfs_rq_show,
84};
85
86static int blk_flags_show(struct seq_file *m, const unsigned long flags,
87 const char *const *flag_name, int flag_name_count)
88{
89 bool sep = false;
90 int i;
91
92 for (i = 0; i < sizeof(flags) * BITS_PER_BYTE; i++) {
93 if (!(flags & BIT(i)))
94 continue;
95 if (sep)
96 seq_puts(m, "|");
97 sep = true;
98 if (i < flag_name_count && flag_name[i])
99 seq_puts(m, flag_name[i]);
100 else
101 seq_printf(m, "%d", i);
102 }
103 return 0;
104}
105
106static int queue_pm_only_show(void *data, struct seq_file *m)
107{
108 struct request_queue *q = data;
109
110 seq_printf(m, "%d\n", atomic_read(&q->pm_only));
111 return 0;
112}
113
114#define QUEUE_FLAG_NAME(name) [QUEUE_FLAG_##name] = #name
115static const char *const blk_queue_flag_name[] = {
116 QUEUE_FLAG_NAME(STOPPED),
117 QUEUE_FLAG_NAME(DYING),
118 QUEUE_FLAG_NAME(NOMERGES),
119 QUEUE_FLAG_NAME(SAME_COMP),
120 QUEUE_FLAG_NAME(FAIL_IO),
121 QUEUE_FLAG_NAME(NONROT),
122 QUEUE_FLAG_NAME(IO_STAT),
123 QUEUE_FLAG_NAME(DISCARD),
124 QUEUE_FLAG_NAME(NOXMERGES),
125 QUEUE_FLAG_NAME(ADD_RANDOM),
126 QUEUE_FLAG_NAME(SECERASE),
127 QUEUE_FLAG_NAME(SAME_FORCE),
128 QUEUE_FLAG_NAME(DEAD),
129 QUEUE_FLAG_NAME(INIT_DONE),
130 QUEUE_FLAG_NAME(POLL),
131 QUEUE_FLAG_NAME(WC),
132 QUEUE_FLAG_NAME(FUA),
133 QUEUE_FLAG_NAME(DAX),
134 QUEUE_FLAG_NAME(STATS),
135 QUEUE_FLAG_NAME(POLL_STATS),
136 QUEUE_FLAG_NAME(REGISTERED),
137 QUEUE_FLAG_NAME(SCSI_PASSTHROUGH),
138 QUEUE_FLAG_NAME(QUIESCED),
139};
140#undef QUEUE_FLAG_NAME
141
142static int queue_state_show(void *data, struct seq_file *m)
143{
144 struct request_queue *q = data;
145
146 blk_flags_show(m, q->queue_flags, blk_queue_flag_name,
147 ARRAY_SIZE(blk_queue_flag_name));
148 seq_puts(m, "\n");
149 return 0;
150}
151
152static ssize_t queue_state_write(void *data, const char __user *buf,
153 size_t count, loff_t *ppos)
154{
155 struct request_queue *q = data;
156 char opbuf[16] = { }, *op;
157
158 /*
159 * The "state" attribute is removed after blk_cleanup_queue() has called
160 * blk_mq_free_queue(). Return if QUEUE_FLAG_DEAD has been set to avoid
161 * triggering a use-after-free.
162 */
163 if (blk_queue_dead(q))
164 return -ENOENT;
165
166 if (count >= sizeof(opbuf)) {
167 pr_err("%s: operation too long\n", __func__);
168 goto inval;
169 }
170
171 if (copy_from_user(opbuf, buf, count))
172 return -EFAULT;
173 op = strstrip(opbuf);
174 if (strcmp(op, "run") == 0) {
175 blk_mq_run_hw_queues(q, true);
176 } else if (strcmp(op, "start") == 0) {
177 blk_mq_start_stopped_hw_queues(q, true);
178 } else if (strcmp(op, "kick") == 0) {
179 blk_mq_kick_requeue_list(q);
180 } else {
181 pr_err("%s: unsupported operation '%s'\n", __func__, op);
182inval:
183 pr_err("%s: use 'run', 'start' or 'kick'\n", __func__);
184 return -EINVAL;
185 }
186 return count;
187}
188
189static int queue_write_hint_show(void *data, struct seq_file *m)
190{
191 struct request_queue *q = data;
192 int i;
193
194 for (i = 0; i < BLK_MAX_WRITE_HINTS; i++)
195 seq_printf(m, "hint%d: %llu\n", i, q->write_hints[i]);
196
197 return 0;
198}
199
200static ssize_t queue_write_hint_store(void *data, const char __user *buf,
201 size_t count, loff_t *ppos)
202{
203 struct request_queue *q = data;
204 int i;
205
206 for (i = 0; i < BLK_MAX_WRITE_HINTS; i++)
207 q->write_hints[i] = 0;
208
209 return count;
210}
211
212static const struct blk_mq_debugfs_attr blk_mq_debugfs_queue_attrs[] = {
213 { "poll_stat", 0400, queue_poll_stat_show },
214 { "requeue_list", 0400, .seq_ops = &queue_requeue_list_seq_ops },
215 { "pm_only", 0600, queue_pm_only_show, NULL },
216 { "state", 0600, queue_state_show, queue_state_write },
217 { "write_hints", 0600, queue_write_hint_show, queue_write_hint_store },
218 { "zone_wlock", 0400, queue_zone_wlock_show, NULL },
219 { },
220};
221
222#define HCTX_STATE_NAME(name) [BLK_MQ_S_##name] = #name
223static const char *const hctx_state_name[] = {
224 HCTX_STATE_NAME(STOPPED),
225 HCTX_STATE_NAME(TAG_ACTIVE),
226 HCTX_STATE_NAME(SCHED_RESTART),
227};
228#undef HCTX_STATE_NAME
229
230static int hctx_state_show(void *data, struct seq_file *m)
231{
232 struct blk_mq_hw_ctx *hctx = data;
233
234 blk_flags_show(m, hctx->state, hctx_state_name,
235 ARRAY_SIZE(hctx_state_name));
236 seq_puts(m, "\n");
237 return 0;
238}
239
240#define BLK_TAG_ALLOC_NAME(name) [BLK_TAG_ALLOC_##name] = #name
241static const char *const alloc_policy_name[] = {
242 BLK_TAG_ALLOC_NAME(FIFO),
243 BLK_TAG_ALLOC_NAME(RR),
244};
245#undef BLK_TAG_ALLOC_NAME
246
247#define HCTX_FLAG_NAME(name) [ilog2(BLK_MQ_F_##name)] = #name
248static const char *const hctx_flag_name[] = {
249 HCTX_FLAG_NAME(SHOULD_MERGE),
250 HCTX_FLAG_NAME(TAG_SHARED),
251 HCTX_FLAG_NAME(BLOCKING),
252 HCTX_FLAG_NAME(NO_SCHED),
253};
254#undef HCTX_FLAG_NAME
255
256static int hctx_flags_show(void *data, struct seq_file *m)
257{
258 struct blk_mq_hw_ctx *hctx = data;
259 const int alloc_policy = BLK_MQ_FLAG_TO_ALLOC_POLICY(hctx->flags);
260
261 seq_puts(m, "alloc_policy=");
262 if (alloc_policy < ARRAY_SIZE(alloc_policy_name) &&
263 alloc_policy_name[alloc_policy])
264 seq_puts(m, alloc_policy_name[alloc_policy]);
265 else
266 seq_printf(m, "%d", alloc_policy);
267 seq_puts(m, " ");
268 blk_flags_show(m,
269 hctx->flags ^ BLK_ALLOC_POLICY_TO_MQ_FLAG(alloc_policy),
270 hctx_flag_name, ARRAY_SIZE(hctx_flag_name));
271 seq_puts(m, "\n");
272 return 0;
273}
274
275#define REQ_OP_NAME(name) [REQ_OP_##name] = #name
276static const char *const op_name[] = {
277 REQ_OP_NAME(READ),
278 REQ_OP_NAME(WRITE),
279 REQ_OP_NAME(FLUSH),
280 REQ_OP_NAME(DISCARD),
281 REQ_OP_NAME(SECURE_ERASE),
282 REQ_OP_NAME(ZONE_RESET),
283 REQ_OP_NAME(WRITE_SAME),
284 REQ_OP_NAME(WRITE_ZEROES),
285 REQ_OP_NAME(SCSI_IN),
286 REQ_OP_NAME(SCSI_OUT),
287 REQ_OP_NAME(DRV_IN),
288 REQ_OP_NAME(DRV_OUT),
289};
290#undef REQ_OP_NAME
291
292#define CMD_FLAG_NAME(name) [__REQ_##name] = #name
293static const char *const cmd_flag_name[] = {
294 CMD_FLAG_NAME(FAILFAST_DEV),
295 CMD_FLAG_NAME(FAILFAST_TRANSPORT),
296 CMD_FLAG_NAME(FAILFAST_DRIVER),
297 CMD_FLAG_NAME(SYNC),
298 CMD_FLAG_NAME(META),
299 CMD_FLAG_NAME(PRIO),
300 CMD_FLAG_NAME(NOMERGE),
301 CMD_FLAG_NAME(IDLE),
302 CMD_FLAG_NAME(INTEGRITY),
303 CMD_FLAG_NAME(FUA),
304 CMD_FLAG_NAME(PREFLUSH),
305 CMD_FLAG_NAME(RAHEAD),
306 CMD_FLAG_NAME(BACKGROUND),
307 CMD_FLAG_NAME(NOWAIT),
308 CMD_FLAG_NAME(NOUNMAP),
309 CMD_FLAG_NAME(HIPRI),
310};
311#undef CMD_FLAG_NAME
312
313#define RQF_NAME(name) [ilog2((__force u32)RQF_##name)] = #name
314static const char *const rqf_name[] = {
315 RQF_NAME(SORTED),
316 RQF_NAME(STARTED),
317 RQF_NAME(SOFTBARRIER),
318 RQF_NAME(FLUSH_SEQ),
319 RQF_NAME(MIXED_MERGE),
320 RQF_NAME(MQ_INFLIGHT),
321 RQF_NAME(DONTPREP),
322 RQF_NAME(PREEMPT),
323 RQF_NAME(COPY_USER),
324 RQF_NAME(FAILED),
325 RQF_NAME(QUIET),
326 RQF_NAME(ELVPRIV),
327 RQF_NAME(IO_STAT),
328 RQF_NAME(ALLOCED),
329 RQF_NAME(PM),
330 RQF_NAME(HASHED),
331 RQF_NAME(STATS),
332 RQF_NAME(SPECIAL_PAYLOAD),
333 RQF_NAME(ZONE_WRITE_LOCKED),
334 RQF_NAME(MQ_POLL_SLEPT),
335};
336#undef RQF_NAME
337
338static const char *const blk_mq_rq_state_name_array[] = {
339 [MQ_RQ_IDLE] = "idle",
340 [MQ_RQ_IN_FLIGHT] = "in_flight",
341 [MQ_RQ_COMPLETE] = "complete",
342};
343
344static const char *blk_mq_rq_state_name(enum mq_rq_state rq_state)
345{
346 if (WARN_ON_ONCE((unsigned int)rq_state >=
347 ARRAY_SIZE(blk_mq_rq_state_name_array)))
348 return "(?)";
349 return blk_mq_rq_state_name_array[rq_state];
350}
351
352int __blk_mq_debugfs_rq_show(struct seq_file *m, struct request *rq)
353{
354 const struct blk_mq_ops *const mq_ops = rq->q->mq_ops;
355 const unsigned int op = rq->cmd_flags & REQ_OP_MASK;
356
357 seq_printf(m, "%p {.op=", rq);
358 if (op < ARRAY_SIZE(op_name) && op_name[op])
359 seq_printf(m, "%s", op_name[op]);
360 else
361 seq_printf(m, "%d", op);
362 seq_puts(m, ", .cmd_flags=");
363 blk_flags_show(m, rq->cmd_flags & ~REQ_OP_MASK, cmd_flag_name,
364 ARRAY_SIZE(cmd_flag_name));
365 seq_puts(m, ", .rq_flags=");
366 blk_flags_show(m, (__force unsigned int)rq->rq_flags, rqf_name,
367 ARRAY_SIZE(rqf_name));
368 seq_printf(m, ", .state=%s", blk_mq_rq_state_name(blk_mq_rq_state(rq)));
369 seq_printf(m, ", .tag=%d, .internal_tag=%d", rq->tag,
370 rq->internal_tag);
371 if (mq_ops->show_rq)
372 mq_ops->show_rq(m, rq);
373 seq_puts(m, "}\n");
374 return 0;
375}
376EXPORT_SYMBOL_GPL(__blk_mq_debugfs_rq_show);
377
378int blk_mq_debugfs_rq_show(struct seq_file *m, void *v)
379{
380 return __blk_mq_debugfs_rq_show(m, list_entry_rq(v));
381}
382EXPORT_SYMBOL_GPL(blk_mq_debugfs_rq_show);
383
384static void *hctx_dispatch_start(struct seq_file *m, loff_t *pos)
385 __acquires(&hctx->lock)
386{
387 struct blk_mq_hw_ctx *hctx = m->private;
388
389 spin_lock(&hctx->lock);
390 return seq_list_start(&hctx->dispatch, *pos);
391}
392
393static void *hctx_dispatch_next(struct seq_file *m, void *v, loff_t *pos)
394{
395 struct blk_mq_hw_ctx *hctx = m->private;
396
397 return seq_list_next(v, &hctx->dispatch, pos);
398}
399
400static void hctx_dispatch_stop(struct seq_file *m, void *v)
401 __releases(&hctx->lock)
402{
403 struct blk_mq_hw_ctx *hctx = m->private;
404
405 spin_unlock(&hctx->lock);
406}
407
408static const struct seq_operations hctx_dispatch_seq_ops = {
409 .start = hctx_dispatch_start,
410 .next = hctx_dispatch_next,
411 .stop = hctx_dispatch_stop,
412 .show = blk_mq_debugfs_rq_show,
413};
414
415struct show_busy_params {
416 struct seq_file *m;
417 struct blk_mq_hw_ctx *hctx;
418};
419
420/*
421 * Note: the state of a request may change while this function is in progress,
422 * e.g. due to a concurrent blk_mq_finish_request() call. Returns true to
423 * keep iterating requests.
424 */
425static bool hctx_show_busy_rq(struct request *rq, void *data, bool reserved)
426{
427 const struct show_busy_params *params = data;
428
429 if (rq->mq_hctx == params->hctx)
430 __blk_mq_debugfs_rq_show(params->m,
431 list_entry_rq(&rq->queuelist));
432
433 return true;
434}
435
436static int hctx_busy_show(void *data, struct seq_file *m)
437{
438 struct blk_mq_hw_ctx *hctx = data;
439 struct show_busy_params params = { .m = m, .hctx = hctx };
440
441 blk_mq_tagset_busy_iter(hctx->queue->tag_set, hctx_show_busy_rq,
442 &params);
443
444 return 0;
445}
446
447static const char *const hctx_types[] = {
448 [HCTX_TYPE_DEFAULT] = "default",
449 [HCTX_TYPE_READ] = "read",
450 [HCTX_TYPE_POLL] = "poll",
451};
452
453static int hctx_type_show(void *data, struct seq_file *m)
454{
455 struct blk_mq_hw_ctx *hctx = data;
456
457 BUILD_BUG_ON(ARRAY_SIZE(hctx_types) != HCTX_MAX_TYPES);
458 seq_printf(m, "%s\n", hctx_types[hctx->type]);
459 return 0;
460}
461
462static int hctx_ctx_map_show(void *data, struct seq_file *m)
463{
464 struct blk_mq_hw_ctx *hctx = data;
465
466 sbitmap_bitmap_show(&hctx->ctx_map, m);
467 return 0;
468}
469
470static void blk_mq_debugfs_tags_show(struct seq_file *m,
471 struct blk_mq_tags *tags)
472{
473 seq_printf(m, "nr_tags=%u\n", tags->nr_tags);
474 seq_printf(m, "nr_reserved_tags=%u\n", tags->nr_reserved_tags);
475 seq_printf(m, "active_queues=%d\n",
476 atomic_read(&tags->active_queues));
477
478 seq_puts(m, "\nbitmap_tags:\n");
479 sbitmap_queue_show(&tags->bitmap_tags, m);
480
481 if (tags->nr_reserved_tags) {
482 seq_puts(m, "\nbreserved_tags:\n");
483 sbitmap_queue_show(&tags->breserved_tags, m);
484 }
485}
486
487static int hctx_tags_show(void *data, struct seq_file *m)
488{
489 struct blk_mq_hw_ctx *hctx = data;
490 struct request_queue *q = hctx->queue;
491 int res;
492
493 res = mutex_lock_interruptible(&q->sysfs_lock);
494 if (res)
495 goto out;
496 if (hctx->tags)
497 blk_mq_debugfs_tags_show(m, hctx->tags);
498 mutex_unlock(&q->sysfs_lock);
499
500out:
501 return res;
502}
503
504static int hctx_tags_bitmap_show(void *data, struct seq_file *m)
505{
506 struct blk_mq_hw_ctx *hctx = data;
507 struct request_queue *q = hctx->queue;
508 int res;
509
510 res = mutex_lock_interruptible(&q->sysfs_lock);
511 if (res)
512 goto out;
513 if (hctx->tags)
514 sbitmap_bitmap_show(&hctx->tags->bitmap_tags.sb, m);
515 mutex_unlock(&q->sysfs_lock);
516
517out:
518 return res;
519}
520
521static int hctx_sched_tags_show(void *data, struct seq_file *m)
522{
523 struct blk_mq_hw_ctx *hctx = data;
524 struct request_queue *q = hctx->queue;
525 int res;
526
527 res = mutex_lock_interruptible(&q->sysfs_lock);
528 if (res)
529 goto out;
530 if (hctx->sched_tags)
531 blk_mq_debugfs_tags_show(m, hctx->sched_tags);
532 mutex_unlock(&q->sysfs_lock);
533
534out:
535 return res;
536}
537
538static int hctx_sched_tags_bitmap_show(void *data, struct seq_file *m)
539{
540 struct blk_mq_hw_ctx *hctx = data;
541 struct request_queue *q = hctx->queue;
542 int res;
543
544 res = mutex_lock_interruptible(&q->sysfs_lock);
545 if (res)
546 goto out;
547 if (hctx->sched_tags)
548 sbitmap_bitmap_show(&hctx->sched_tags->bitmap_tags.sb, m);
549 mutex_unlock(&q->sysfs_lock);
550
551out:
552 return res;
553}
554
555static int hctx_io_poll_show(void *data, struct seq_file *m)
556{
557 struct blk_mq_hw_ctx *hctx = data;
558
559 seq_printf(m, "considered=%lu\n", hctx->poll_considered);
560 seq_printf(m, "invoked=%lu\n", hctx->poll_invoked);
561 seq_printf(m, "success=%lu\n", hctx->poll_success);
562 return 0;
563}
564
565static ssize_t hctx_io_poll_write(void *data, const char __user *buf,
566 size_t count, loff_t *ppos)
567{
568 struct blk_mq_hw_ctx *hctx = data;
569
570 hctx->poll_considered = hctx->poll_invoked = hctx->poll_success = 0;
571 return count;
572}
573
574static int hctx_dispatched_show(void *data, struct seq_file *m)
575{
576 struct blk_mq_hw_ctx *hctx = data;
577 int i;
578
579 seq_printf(m, "%8u\t%lu\n", 0U, hctx->dispatched[0]);
580
581 for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER - 1; i++) {
582 unsigned int d = 1U << (i - 1);
583
584 seq_printf(m, "%8u\t%lu\n", d, hctx->dispatched[i]);
585 }
586
587 seq_printf(m, "%8u+\t%lu\n", 1U << (i - 1), hctx->dispatched[i]);
588 return 0;
589}
590
591static ssize_t hctx_dispatched_write(void *data, const char __user *buf,
592 size_t count, loff_t *ppos)
593{
594 struct blk_mq_hw_ctx *hctx = data;
595 int i;
596
597 for (i = 0; i < BLK_MQ_MAX_DISPATCH_ORDER; i++)
598 hctx->dispatched[i] = 0;
599 return count;
600}
601
602static int hctx_queued_show(void *data, struct seq_file *m)
603{
604 struct blk_mq_hw_ctx *hctx = data;
605
606 seq_printf(m, "%lu\n", hctx->queued);
607 return 0;
608}
609
610static ssize_t hctx_queued_write(void *data, const char __user *buf,
611 size_t count, loff_t *ppos)
612{
613 struct blk_mq_hw_ctx *hctx = data;
614
615 hctx->queued = 0;
616 return count;
617}
618
619static int hctx_run_show(void *data, struct seq_file *m)
620{
621 struct blk_mq_hw_ctx *hctx = data;
622
623 seq_printf(m, "%lu\n", hctx->run);
624 return 0;
625}
626
627static ssize_t hctx_run_write(void *data, const char __user *buf, size_t count,
628 loff_t *ppos)
629{
630 struct blk_mq_hw_ctx *hctx = data;
631
632 hctx->run = 0;
633 return count;
634}
635
636static int hctx_active_show(void *data, struct seq_file *m)
637{
638 struct blk_mq_hw_ctx *hctx = data;
639
640 seq_printf(m, "%d\n", atomic_read(&hctx->nr_active));
641 return 0;
642}
643
644static int hctx_dispatch_busy_show(void *data, struct seq_file *m)
645{
646 struct blk_mq_hw_ctx *hctx = data;
647
648 seq_printf(m, "%u\n", hctx->dispatch_busy);
649 return 0;
650}
651
652#define CTX_RQ_SEQ_OPS(name, type) \
653static void *ctx_##name##_rq_list_start(struct seq_file *m, loff_t *pos) \
654 __acquires(&ctx->lock) \
655{ \
656 struct blk_mq_ctx *ctx = m->private; \
657 \
658 spin_lock(&ctx->lock); \
659 return seq_list_start(&ctx->rq_lists[type], *pos); \
660} \
661 \
662static void *ctx_##name##_rq_list_next(struct seq_file *m, void *v, \
663 loff_t *pos) \
664{ \
665 struct blk_mq_ctx *ctx = m->private; \
666 \
667 return seq_list_next(v, &ctx->rq_lists[type], pos); \
668} \
669 \
670static void ctx_##name##_rq_list_stop(struct seq_file *m, void *v) \
671 __releases(&ctx->lock) \
672{ \
673 struct blk_mq_ctx *ctx = m->private; \
674 \
675 spin_unlock(&ctx->lock); \
676} \
677 \
678static const struct seq_operations ctx_##name##_rq_list_seq_ops = { \
679 .start = ctx_##name##_rq_list_start, \
680 .next = ctx_##name##_rq_list_next, \
681 .stop = ctx_##name##_rq_list_stop, \
682 .show = blk_mq_debugfs_rq_show, \
683}
684
685CTX_RQ_SEQ_OPS(default, HCTX_TYPE_DEFAULT);
686CTX_RQ_SEQ_OPS(read, HCTX_TYPE_READ);
687CTX_RQ_SEQ_OPS(poll, HCTX_TYPE_POLL);
688
689static int ctx_dispatched_show(void *data, struct seq_file *m)
690{
691 struct blk_mq_ctx *ctx = data;
692
693 seq_printf(m, "%lu %lu\n", ctx->rq_dispatched[1], ctx->rq_dispatched[0]);
694 return 0;
695}
696
697static ssize_t ctx_dispatched_write(void *data, const char __user *buf,
698 size_t count, loff_t *ppos)
699{
700 struct blk_mq_ctx *ctx = data;
701
702 ctx->rq_dispatched[0] = ctx->rq_dispatched[1] = 0;
703 return count;
704}
705
706static int ctx_merged_show(void *data, struct seq_file *m)
707{
708 struct blk_mq_ctx *ctx = data;
709
710 seq_printf(m, "%lu\n", ctx->rq_merged);
711 return 0;
712}
713
714static ssize_t ctx_merged_write(void *data, const char __user *buf,
715 size_t count, loff_t *ppos)
716{
717 struct blk_mq_ctx *ctx = data;
718
719 ctx->rq_merged = 0;
720 return count;
721}
722
723static int ctx_completed_show(void *data, struct seq_file *m)
724{
725 struct blk_mq_ctx *ctx = data;
726
727 seq_printf(m, "%lu %lu\n", ctx->rq_completed[1], ctx->rq_completed[0]);
728 return 0;
729}
730
731static ssize_t ctx_completed_write(void *data, const char __user *buf,
732 size_t count, loff_t *ppos)
733{
734 struct blk_mq_ctx *ctx = data;
735
736 ctx->rq_completed[0] = ctx->rq_completed[1] = 0;
737 return count;
738}
739
740static int blk_mq_debugfs_show(struct seq_file *m, void *v)
741{
742 const struct blk_mq_debugfs_attr *attr = m->private;
743 void *data = d_inode(m->file->f_path.dentry->d_parent)->i_private;
744
745 return attr->show(data, m);
746}
747
748static ssize_t blk_mq_debugfs_write(struct file *file, const char __user *buf,
749 size_t count, loff_t *ppos)
750{
751 struct seq_file *m = file->private_data;
752 const struct blk_mq_debugfs_attr *attr = m->private;
753 void *data = d_inode(file->f_path.dentry->d_parent)->i_private;
754
755 /*
756 * Attributes that only implement .seq_ops are read-only and 'attr' is
757 * the same with 'data' in this case.
758 */
759 if (attr == data || !attr->write)
760 return -EPERM;
761
762 return attr->write(data, buf, count, ppos);
763}
764
765static int blk_mq_debugfs_open(struct inode *inode, struct file *file)
766{
767 const struct blk_mq_debugfs_attr *attr = inode->i_private;
768 void *data = d_inode(file->f_path.dentry->d_parent)->i_private;
769 struct seq_file *m;
770 int ret;
771
772 if (attr->seq_ops) {
773 ret = seq_open(file, attr->seq_ops);
774 if (!ret) {
775 m = file->private_data;
776 m->private = data;
777 }
778 return ret;
779 }
780
781 if (WARN_ON_ONCE(!attr->show))
782 return -EPERM;
783
784 return single_open(file, blk_mq_debugfs_show, inode->i_private);
785}
786
787static int blk_mq_debugfs_release(struct inode *inode, struct file *file)
788{
789 const struct blk_mq_debugfs_attr *attr = inode->i_private;
790
791 if (attr->show)
792 return single_release(inode, file);
793 else
794 return seq_release(inode, file);
795}
796
797static const struct file_operations blk_mq_debugfs_fops = {
798 .open = blk_mq_debugfs_open,
799 .read = seq_read,
800 .write = blk_mq_debugfs_write,
801 .llseek = seq_lseek,
802 .release = blk_mq_debugfs_release,
803};
804
805static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_attrs[] = {
806 {"state", 0400, hctx_state_show},
807 {"flags", 0400, hctx_flags_show},
808 {"dispatch", 0400, .seq_ops = &hctx_dispatch_seq_ops},
809 {"busy", 0400, hctx_busy_show},
810 {"ctx_map", 0400, hctx_ctx_map_show},
811 {"tags", 0400, hctx_tags_show},
812 {"tags_bitmap", 0400, hctx_tags_bitmap_show},
813 {"sched_tags", 0400, hctx_sched_tags_show},
814 {"sched_tags_bitmap", 0400, hctx_sched_tags_bitmap_show},
815 {"io_poll", 0600, hctx_io_poll_show, hctx_io_poll_write},
816 {"dispatched", 0600, hctx_dispatched_show, hctx_dispatched_write},
817 {"queued", 0600, hctx_queued_show, hctx_queued_write},
818 {"run", 0600, hctx_run_show, hctx_run_write},
819 {"active", 0400, hctx_active_show},
820 {"dispatch_busy", 0400, hctx_dispatch_busy_show},
821 {"type", 0400, hctx_type_show},
822 {},
823};
824
825static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = {
826 {"default_rq_list", 0400, .seq_ops = &ctx_default_rq_list_seq_ops},
827 {"read_rq_list", 0400, .seq_ops = &ctx_read_rq_list_seq_ops},
828 {"poll_rq_list", 0400, .seq_ops = &ctx_poll_rq_list_seq_ops},
829 {"dispatched", 0600, ctx_dispatched_show, ctx_dispatched_write},
830 {"merged", 0600, ctx_merged_show, ctx_merged_write},
831 {"completed", 0600, ctx_completed_show, ctx_completed_write},
832 {},
833};
834
835static bool debugfs_create_files(struct dentry *parent, void *data,
836 const struct blk_mq_debugfs_attr *attr)
837{
838 if (IS_ERR_OR_NULL(parent))
839 return false;
840
841 d_inode(parent)->i_private = data;
842
843 for (; attr->name; attr++) {
844 if (!debugfs_create_file(attr->name, attr->mode, parent,
845 (void *)attr, &blk_mq_debugfs_fops))
846 return false;
847 }
848 return true;
849}
850
851int blk_mq_debugfs_register(struct request_queue *q)
852{
853 struct blk_mq_hw_ctx *hctx;
854 int i;
855
856 if (!blk_debugfs_root)
857 return -ENOENT;
858
859 q->debugfs_dir = debugfs_create_dir(kobject_name(q->kobj.parent),
860 blk_debugfs_root);
861 if (!q->debugfs_dir)
862 return -ENOMEM;
863
864 if (!debugfs_create_files(q->debugfs_dir, q,
865 blk_mq_debugfs_queue_attrs))
866 goto err;
867
868 /*
869 * blk_mq_init_sched() attempted to do this already, but q->debugfs_dir
870 * didn't exist yet (because we don't know what to name the directory
871 * until the queue is registered to a gendisk).
872 */
873 if (q->elevator && !q->sched_debugfs_dir)
874 blk_mq_debugfs_register_sched(q);
875
876 /* Similarly, blk_mq_init_hctx() couldn't do this previously. */
877 queue_for_each_hw_ctx(q, hctx, i) {
878 if (!hctx->debugfs_dir && blk_mq_debugfs_register_hctx(q, hctx))
879 goto err;
880 if (q->elevator && !hctx->sched_debugfs_dir &&
881 blk_mq_debugfs_register_sched_hctx(q, hctx))
882 goto err;
883 }
884
885 if (q->rq_qos) {
886 struct rq_qos *rqos = q->rq_qos;
887
888 while (rqos) {
889 blk_mq_debugfs_register_rqos(rqos);
890 rqos = rqos->next;
891 }
892 }
893
894 return 0;
895
896err:
897 blk_mq_debugfs_unregister(q);
898 return -ENOMEM;
899}
900
901void blk_mq_debugfs_unregister(struct request_queue *q)
902{
903 debugfs_remove_recursive(q->debugfs_dir);
904 q->sched_debugfs_dir = NULL;
905 q->debugfs_dir = NULL;
906}
907
908static int blk_mq_debugfs_register_ctx(struct blk_mq_hw_ctx *hctx,
909 struct blk_mq_ctx *ctx)
910{
911 struct dentry *ctx_dir;
912 char name[20];
913
914 snprintf(name, sizeof(name), "cpu%u", ctx->cpu);
915 ctx_dir = debugfs_create_dir(name, hctx->debugfs_dir);
916 if (!ctx_dir)
917 return -ENOMEM;
918
919 if (!debugfs_create_files(ctx_dir, ctx, blk_mq_debugfs_ctx_attrs))
920 return -ENOMEM;
921
922 return 0;
923}
924
925int blk_mq_debugfs_register_hctx(struct request_queue *q,
926 struct blk_mq_hw_ctx *hctx)
927{
928 struct blk_mq_ctx *ctx;
929 char name[20];
930 int i;
931
932 if (!q->debugfs_dir)
933 return -ENOENT;
934
935 snprintf(name, sizeof(name), "hctx%u", hctx->queue_num);
936 hctx->debugfs_dir = debugfs_create_dir(name, q->debugfs_dir);
937 if (!hctx->debugfs_dir)
938 return -ENOMEM;
939
940 if (!debugfs_create_files(hctx->debugfs_dir, hctx,
941 blk_mq_debugfs_hctx_attrs))
942 goto err;
943
944 hctx_for_each_ctx(hctx, ctx, i) {
945 if (blk_mq_debugfs_register_ctx(hctx, ctx))
946 goto err;
947 }
948
949 return 0;
950
951err:
952 blk_mq_debugfs_unregister_hctx(hctx);
953 return -ENOMEM;
954}
955
956void blk_mq_debugfs_unregister_hctx(struct blk_mq_hw_ctx *hctx)
957{
958 debugfs_remove_recursive(hctx->debugfs_dir);
959 hctx->sched_debugfs_dir = NULL;
960 hctx->debugfs_dir = NULL;
961}
962
963int blk_mq_debugfs_register_hctxs(struct request_queue *q)
964{
965 struct blk_mq_hw_ctx *hctx;
966 int i;
967
968 queue_for_each_hw_ctx(q, hctx, i) {
969 if (blk_mq_debugfs_register_hctx(q, hctx))
970 return -ENOMEM;
971 }
972
973 return 0;
974}
975
976void blk_mq_debugfs_unregister_hctxs(struct request_queue *q)
977{
978 struct blk_mq_hw_ctx *hctx;
979 int i;
980
981 queue_for_each_hw_ctx(q, hctx, i)
982 blk_mq_debugfs_unregister_hctx(hctx);
983}
984
985int blk_mq_debugfs_register_sched(struct request_queue *q)
986{
987 struct elevator_type *e = q->elevator->type;
988
989 if (!q->debugfs_dir)
990 return -ENOENT;
991
992 if (!e->queue_debugfs_attrs)
993 return 0;
994
995 q->sched_debugfs_dir = debugfs_create_dir("sched", q->debugfs_dir);
996 if (!q->sched_debugfs_dir)
997 return -ENOMEM;
998
999 if (!debugfs_create_files(q->sched_debugfs_dir, q,
1000 e->queue_debugfs_attrs))
1001 goto err;
1002
1003 return 0;
1004
1005err:
1006 blk_mq_debugfs_unregister_sched(q);
1007 return -ENOMEM;
1008}
1009
1010void blk_mq_debugfs_unregister_sched(struct request_queue *q)
1011{
1012 debugfs_remove_recursive(q->sched_debugfs_dir);
1013 q->sched_debugfs_dir = NULL;
1014}
1015
1016void blk_mq_debugfs_unregister_rqos(struct rq_qos *rqos)
1017{
1018 debugfs_remove_recursive(rqos->debugfs_dir);
1019 rqos->debugfs_dir = NULL;
1020}
1021
1022int blk_mq_debugfs_register_rqos(struct rq_qos *rqos)
1023{
1024 struct request_queue *q = rqos->q;
1025 const char *dir_name = rq_qos_id_to_name(rqos->id);
1026
1027 if (!q->debugfs_dir)
1028 return -ENOENT;
1029
1030 if (rqos->debugfs_dir || !rqos->ops->debugfs_attrs)
1031 return 0;
1032
1033 if (!q->rqos_debugfs_dir) {
1034 q->rqos_debugfs_dir = debugfs_create_dir("rqos",
1035 q->debugfs_dir);
1036 if (!q->rqos_debugfs_dir)
1037 return -ENOMEM;
1038 }
1039
1040 rqos->debugfs_dir = debugfs_create_dir(dir_name,
1041 rqos->q->rqos_debugfs_dir);
1042 if (!rqos->debugfs_dir)
1043 return -ENOMEM;
1044
1045 if (!debugfs_create_files(rqos->debugfs_dir, rqos,
1046 rqos->ops->debugfs_attrs))
1047 goto err;
1048 return 0;
1049 err:
1050 blk_mq_debugfs_unregister_rqos(rqos);
1051 return -ENOMEM;
1052}
1053
1054void blk_mq_debugfs_unregister_queue_rqos(struct request_queue *q)
1055{
1056 debugfs_remove_recursive(q->rqos_debugfs_dir);
1057 q->rqos_debugfs_dir = NULL;
1058}
1059
1060int blk_mq_debugfs_register_sched_hctx(struct request_queue *q,
1061 struct blk_mq_hw_ctx *hctx)
1062{
1063 struct elevator_type *e = q->elevator->type;
1064
1065 if (!hctx->debugfs_dir)
1066 return -ENOENT;
1067
1068 if (!e->hctx_debugfs_attrs)
1069 return 0;
1070
1071 hctx->sched_debugfs_dir = debugfs_create_dir("sched",
1072 hctx->debugfs_dir);
1073 if (!hctx->sched_debugfs_dir)
1074 return -ENOMEM;
1075
1076 if (!debugfs_create_files(hctx->sched_debugfs_dir, hctx,
1077 e->hctx_debugfs_attrs))
1078 return -ENOMEM;
1079
1080 return 0;
1081}
1082
1083void blk_mq_debugfs_unregister_sched_hctx(struct blk_mq_hw_ctx *hctx)
1084{
1085 debugfs_remove_recursive(hctx->sched_debugfs_dir);
1086 hctx->sched_debugfs_dir = NULL;
1087}
1088