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