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  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (C) 2017 Facebook
  4 */
  5
  6#include <linux/kernel.h>
  7#include <linux/blkdev.h>
  8#include <linux/debugfs.h>
  9
 10#include <linux/blk-mq.h>
 11#include "blk.h"
 12#include "blk-mq.h"
 13#include "blk-mq-debugfs.h"
 14#include "blk-mq-tag.h"
 15#include "blk-rq-qos.h"
 16
 17static void print_stat(struct seq_file *m, struct blk_rq_stat *stat)
 18{
 19	if (stat->nr_samples) {
 20		seq_printf(m, "samples=%d, mean=%llu, min=%llu, max=%llu",
 21			   stat->nr_samples, stat->mean, stat->min, stat->max);
 22	} else {
 23		seq_puts(m, "samples=0");
 24	}
 25}
 26
 27static int queue_poll_stat_show(void *data, struct seq_file *m)
 28{
 29	struct request_queue *q = data;
 30	int bucket;
 31
 32	for (bucket = 0; bucket < (BLK_MQ_POLL_STATS_BKTS / 2); bucket++) {
 33		seq_printf(m, "read  (%d Bytes): ", 1 << (9 + bucket));
 34		print_stat(m, &q->poll_stat[2 * bucket]);
 35		seq_puts(m, "\n");
 36
 37		seq_printf(m, "write (%d Bytes): ",  1 << (9 + bucket));
 38		print_stat(m, &q->poll_stat[2 * bucket + 1]);
 39		seq_puts(m, "\n");
 40	}
 41	return 0;
 42}
 43
 44static void *queue_requeue_list_start(struct seq_file *m, loff_t *pos)
 45	__acquires(&q->requeue_lock)
 46{
 47	struct request_queue *q = m->private;
 48
 49	spin_lock_irq(&q->requeue_lock);
 50	return seq_list_start(&q->requeue_list, *pos);
 51}
 52
 53static void *queue_requeue_list_next(struct seq_file *m, void *v, loff_t *pos)
 54{
 55	struct request_queue *q = m->private;
 56
 57	return seq_list_next(v, &q->requeue_list, pos);
 58}
 59
 60static void queue_requeue_list_stop(struct seq_file *m, void *v)
 61	__releases(&q->requeue_lock)
 62{
 63	struct request_queue *q = m->private;
 64
 65	spin_unlock_irq(&q->requeue_lock);
 66}
 67
 68static const struct seq_operations queue_requeue_list_seq_ops = {
 69	.start	= queue_requeue_list_start,
 70	.next	= queue_requeue_list_next,
 71	.stop	= queue_requeue_list_stop,
 72	.show	= blk_mq_debugfs_rq_show,
 73};
 74
 75static int blk_flags_show(struct seq_file *m, const unsigned long flags,
 76			  const char *const *flag_name, int flag_name_count)
 77{
 78	bool sep = false;
 79	int i;
 80
 81	for (i = 0; i < sizeof(flags) * BITS_PER_BYTE; i++) {
 82		if (!(flags & BIT(i)))
 83			continue;
 84		if (sep)
 85			seq_puts(m, "|");
 86		sep = true;
 87		if (i < flag_name_count && flag_name[i])
 88			seq_puts(m, flag_name[i]);
 89		else
 90			seq_printf(m, "%d", i);
 91	}
 92	return 0;
 93}
 94
 95static int queue_pm_only_show(void *data, struct seq_file *m)
 96{
 97	struct request_queue *q = data;
 98
 99	seq_printf(m, "%d\n", atomic_read(&q->pm_only));
100	return 0;
101}
102
103#define QUEUE_FLAG_NAME(name) [QUEUE_FLAG_##name] = #name
104static const char *const blk_queue_flag_name[] = {
105	QUEUE_FLAG_NAME(STOPPED),
106	QUEUE_FLAG_NAME(DYING),
107	QUEUE_FLAG_NAME(NOMERGES),
108	QUEUE_FLAG_NAME(SAME_COMP),
109	QUEUE_FLAG_NAME(FAIL_IO),
110	QUEUE_FLAG_NAME(NONROT),
111	QUEUE_FLAG_NAME(IO_STAT),
112	QUEUE_FLAG_NAME(DISCARD),
113	QUEUE_FLAG_NAME(NOXMERGES),
114	QUEUE_FLAG_NAME(ADD_RANDOM),
115	QUEUE_FLAG_NAME(SECERASE),
116	QUEUE_FLAG_NAME(SAME_FORCE),
117	QUEUE_FLAG_NAME(DEAD),
118	QUEUE_FLAG_NAME(INIT_DONE),
119	QUEUE_FLAG_NAME(POLL),
120	QUEUE_FLAG_NAME(WC),
121	QUEUE_FLAG_NAME(FUA),
122	QUEUE_FLAG_NAME(DAX),
123	QUEUE_FLAG_NAME(STATS),
124	QUEUE_FLAG_NAME(POLL_STATS),
125	QUEUE_FLAG_NAME(REGISTERED),
126	QUEUE_FLAG_NAME(SCSI_PASSTHROUGH),
127	QUEUE_FLAG_NAME(QUIESCED),
128	QUEUE_FLAG_NAME(PCI_P2PDMA),
129	QUEUE_FLAG_NAME(ZONE_RESETALL),
130	QUEUE_FLAG_NAME(RQ_ALLOC_TIME),
131};
132#undef QUEUE_FLAG_NAME
133
134static int queue_state_show(void *data, struct seq_file *m)
135{
136	struct request_queue *q = data;
137
138	blk_flags_show(m, q->queue_flags, blk_queue_flag_name,
139		       ARRAY_SIZE(blk_queue_flag_name));
140	seq_puts(m, "\n");
141	return 0;
142}
143
144static ssize_t queue_state_write(void *data, const char __user *buf,
145				 size_t count, loff_t *ppos)
146{
147	struct request_queue *q = data;
148	char opbuf[16] = { }, *op;
149
150	/*
151	 * The "state" attribute is removed after blk_cleanup_queue() has called
152	 * blk_mq_free_queue(). Return if QUEUE_FLAG_DEAD has been set to avoid
153	 * triggering a use-after-free.
154	 */
155	if (blk_queue_dead(q))
156		return -ENOENT;
157
158	if (count >= sizeof(opbuf)) {
159		pr_err("%s: operation too long\n", __func__);
160		goto inval;
161	}
162
163	if (copy_from_user(opbuf, buf, count))
164		return -EFAULT;
165	op = strstrip(opbuf);
166	if (strcmp(op, "run") == 0) {
167		blk_mq_run_hw_queues(q, true);
168	} else if (strcmp(op, "start") == 0) {
169		blk_mq_start_stopped_hw_queues(q, true);
170	} else if (strcmp(op, "kick") == 0) {
171		blk_mq_kick_requeue_list(q);
172	} else {
173		pr_err("%s: unsupported operation '%s'\n", __func__, op);
174inval:
175		pr_err("%s: use 'run', 'start' or 'kick'\n", __func__);
176		return -EINVAL;
177	}
178	return count;
179}
180
181static int queue_write_hint_show(void *data, struct seq_file *m)
182{
183	struct request_queue *q = data;
184	int i;
185
186	for (i = 0; i < BLK_MAX_WRITE_HINTS; i++)
187		seq_printf(m, "hint%d: %llu\n", i, q->write_hints[i]);
188
189	return 0;
190}
191
192static ssize_t queue_write_hint_store(void *data, const char __user *buf,
193				      size_t count, loff_t *ppos)
194{
195	struct request_queue *q = data;
196	int i;
197
198	for (i = 0; i < BLK_MAX_WRITE_HINTS; i++)
199		q->write_hints[i] = 0;
200
201	return count;
202}
203
204static const struct blk_mq_debugfs_attr blk_mq_debugfs_queue_attrs[] = {
205	{ "poll_stat", 0400, queue_poll_stat_show },
206	{ "requeue_list", 0400, .seq_ops = &queue_requeue_list_seq_ops },
207	{ "pm_only", 0600, queue_pm_only_show, NULL },
208	{ "state", 0600, queue_state_show, queue_state_write },
209	{ "write_hints", 0600, queue_write_hint_show, queue_write_hint_store },
210	{ "zone_wlock", 0400, queue_zone_wlock_show, NULL },
211	{ },
212};
213
214#define HCTX_STATE_NAME(name) [BLK_MQ_S_##name] = #name
215static const char *const hctx_state_name[] = {
216	HCTX_STATE_NAME(STOPPED),
217	HCTX_STATE_NAME(TAG_ACTIVE),
218	HCTX_STATE_NAME(SCHED_RESTART),
219	HCTX_STATE_NAME(INACTIVE),
220};
221#undef HCTX_STATE_NAME
222
223static int hctx_state_show(void *data, struct seq_file *m)
224{
225	struct blk_mq_hw_ctx *hctx = data;
226
227	blk_flags_show(m, hctx->state, hctx_state_name,
228		       ARRAY_SIZE(hctx_state_name));
229	seq_puts(m, "\n");
230	return 0;
231}
232
233#define BLK_TAG_ALLOC_NAME(name) [BLK_TAG_ALLOC_##name] = #name
234static const char *const alloc_policy_name[] = {
235	BLK_TAG_ALLOC_NAME(FIFO),
236	BLK_TAG_ALLOC_NAME(RR),
237};
238#undef BLK_TAG_ALLOC_NAME
239
240#define HCTX_FLAG_NAME(name) [ilog2(BLK_MQ_F_##name)] = #name
241static const char *const hctx_flag_name[] = {
242	HCTX_FLAG_NAME(SHOULD_MERGE),
243	HCTX_FLAG_NAME(TAG_SHARED),
244	HCTX_FLAG_NAME(BLOCKING),
245	HCTX_FLAG_NAME(NO_SCHED),
246	HCTX_FLAG_NAME(STACKING),
247};
248#undef HCTX_FLAG_NAME
249
250static int hctx_flags_show(void *data, struct seq_file *m)
251{
252	struct blk_mq_hw_ctx *hctx = data;
253	const int alloc_policy = BLK_MQ_FLAG_TO_ALLOC_POLICY(hctx->flags);
254
255	seq_puts(m, "alloc_policy=");
256	if (alloc_policy < ARRAY_SIZE(alloc_policy_name) &&
257	    alloc_policy_name[alloc_policy])
258		seq_puts(m, alloc_policy_name[alloc_policy]);
259	else
260		seq_printf(m, "%d", alloc_policy);
261	seq_puts(m, " ");
262	blk_flags_show(m,
263		       hctx->flags ^ BLK_ALLOC_POLICY_TO_MQ_FLAG(alloc_policy),
264		       hctx_flag_name, ARRAY_SIZE(hctx_flag_name));
265	seq_puts(m, "\n");
266	return 0;
267}
268
269#define CMD_FLAG_NAME(name) [__REQ_##name] = #name
270static const char *const cmd_flag_name[] = {
271	CMD_FLAG_NAME(FAILFAST_DEV),
272	CMD_FLAG_NAME(FAILFAST_TRANSPORT),
273	CMD_FLAG_NAME(FAILFAST_DRIVER),
274	CMD_FLAG_NAME(SYNC),
275	CMD_FLAG_NAME(META),
276	CMD_FLAG_NAME(PRIO),
277	CMD_FLAG_NAME(NOMERGE),
278	CMD_FLAG_NAME(IDLE),
279	CMD_FLAG_NAME(INTEGRITY),
280	CMD_FLAG_NAME(FUA),
281	CMD_FLAG_NAME(PREFLUSH),
282	CMD_FLAG_NAME(RAHEAD),
283	CMD_FLAG_NAME(BACKGROUND),
284	CMD_FLAG_NAME(NOWAIT),
285	CMD_FLAG_NAME(NOUNMAP),
286	CMD_FLAG_NAME(HIPRI),
287};
288#undef CMD_FLAG_NAME
289
290#define RQF_NAME(name) [ilog2((__force u32)RQF_##name)] = #name
291static const char *const rqf_name[] = {
292	RQF_NAME(SORTED),
293	RQF_NAME(STARTED),
294	RQF_NAME(SOFTBARRIER),
295	RQF_NAME(FLUSH_SEQ),
296	RQF_NAME(MIXED_MERGE),
297	RQF_NAME(MQ_INFLIGHT),
298	RQF_NAME(DONTPREP),
299	RQF_NAME(PREEMPT),
300	RQF_NAME(FAILED),
301	RQF_NAME(QUIET),
302	RQF_NAME(ELVPRIV),
303	RQF_NAME(IO_STAT),
304	RQF_NAME(ALLOCED),
305	RQF_NAME(PM),
306	RQF_NAME(HASHED),
307	RQF_NAME(STATS),
308	RQF_NAME(SPECIAL_PAYLOAD),
309	RQF_NAME(ZONE_WRITE_LOCKED),
310	RQF_NAME(MQ_POLL_SLEPT),
311};
312#undef RQF_NAME
313
314static const char *const blk_mq_rq_state_name_array[] = {
315	[MQ_RQ_IDLE]		= "idle",
316	[MQ_RQ_IN_FLIGHT]	= "in_flight",
317	[MQ_RQ_COMPLETE]	= "complete",
318};
319
320static const char *blk_mq_rq_state_name(enum mq_rq_state rq_state)
321{
322	if (WARN_ON_ONCE((unsigned int)rq_state >=
323			 ARRAY_SIZE(blk_mq_rq_state_name_array)))
324		return "(?)";
325	return blk_mq_rq_state_name_array[rq_state];
326}
327
328int __blk_mq_debugfs_rq_show(struct seq_file *m, struct request *rq)
329{
330	const struct blk_mq_ops *const mq_ops = rq->q->mq_ops;
331	const unsigned int op = req_op(rq);
332	const char *op_str = blk_op_str(op);
333
334	seq_printf(m, "%p {.op=", rq);
335	if (strcmp(op_str, "UNKNOWN") == 0)
336		seq_printf(m, "%u", op);
337	else
338		seq_printf(m, "%s", op_str);
339	seq_puts(m, ", .cmd_flags=");
340	blk_flags_show(m, rq->cmd_flags & ~REQ_OP_MASK, cmd_flag_name,
341		       ARRAY_SIZE(cmd_flag_name));
342	seq_puts(m, ", .rq_flags=");
343	blk_flags_show(m, (__force unsigned int)rq->rq_flags, rqf_name,
344		       ARRAY_SIZE(rqf_name));
345	seq_printf(m, ", .state=%s", blk_mq_rq_state_name(blk_mq_rq_state(rq)));
346	seq_printf(m, ", .tag=%d, .internal_tag=%d", rq->tag,
347		   rq->internal_tag);
348	if (mq_ops->show_rq)
349		mq_ops->show_rq(m, rq);
350	seq_puts(m, "}\n");
351	return 0;
352}
353EXPORT_SYMBOL_GPL(__blk_mq_debugfs_rq_show);
354
355int blk_mq_debugfs_rq_show(struct seq_file *m, void *v)
356{
357	return __blk_mq_debugfs_rq_show(m, list_entry_rq(v));
358}
359EXPORT_SYMBOL_GPL(blk_mq_debugfs_rq_show);
360
361static void *hctx_dispatch_start(struct seq_file *m, loff_t *pos)
362	__acquires(&hctx->lock)
363{
364	struct blk_mq_hw_ctx *hctx = m->private;
365
366	spin_lock(&hctx->lock);
367	return seq_list_start(&hctx->dispatch, *pos);
368}
369
370static void *hctx_dispatch_next(struct seq_file *m, void *v, loff_t *pos)
371{
372	struct blk_mq_hw_ctx *hctx = m->private;
373
374	return seq_list_next(v, &hctx->dispatch, pos);
375}
376
377static void hctx_dispatch_stop(struct seq_file *m, void *v)
378	__releases(&hctx->lock)
379{
380	struct blk_mq_hw_ctx *hctx = m->private;
381
382	spin_unlock(&hctx->lock);
383}
384
385static const struct seq_operations hctx_dispatch_seq_ops = {
386	.start	= hctx_dispatch_start,
387	.next	= hctx_dispatch_next,
388	.stop	= hctx_dispatch_stop,
389	.show	= blk_mq_debugfs_rq_show,
390};
391
392struct show_busy_params {
393	struct seq_file		*m;
394	struct blk_mq_hw_ctx	*hctx;
395};
396
397/*
398 * Note: the state of a request may change while this function is in progress,
399 * e.g. due to a concurrent blk_mq_finish_request() call. Returns true to
400 * keep iterating requests.
401 */
402static bool hctx_show_busy_rq(struct request *rq, void *data, bool reserved)
403{
404	const struct show_busy_params *params = data;
405
406	if (rq->mq_hctx == params->hctx)
407		__blk_mq_debugfs_rq_show(params->m, rq);
408
409	return true;
410}
411
412static int hctx_busy_show(void *data, struct seq_file *m)
413{
414	struct blk_mq_hw_ctx *hctx = data;
415	struct show_busy_params params = { .m = m, .hctx = hctx };
416
417	blk_mq_tagset_busy_iter(hctx->queue->tag_set, hctx_show_busy_rq,
418				&params);
419
420	return 0;
421}
422
423static const char *const hctx_types[] = {
424	[HCTX_TYPE_DEFAULT]	= "default",
425	[HCTX_TYPE_READ]	= "read",
426	[HCTX_TYPE_POLL]	= "poll",
427};
428
429static int hctx_type_show(void *data, struct seq_file *m)
430{
431	struct blk_mq_hw_ctx *hctx = data;
432
433	BUILD_BUG_ON(ARRAY_SIZE(hctx_types) != HCTX_MAX_TYPES);
434	seq_printf(m, "%s\n", hctx_types[hctx->type]);
435	return 0;
436}
437
438static int hctx_ctx_map_show(void *data, struct seq_file *m)
439{
440	struct blk_mq_hw_ctx *hctx = data;
441
442	sbitmap_bitmap_show(&hctx->ctx_map, m);
443	return 0;
444}
445
446static void blk_mq_debugfs_tags_show(struct seq_file *m,
447				     struct blk_mq_tags *tags)
448{
449	seq_printf(m, "nr_tags=%u\n", tags->nr_tags);
450	seq_printf(m, "nr_reserved_tags=%u\n", tags->nr_reserved_tags);
451	seq_printf(m, "active_queues=%d\n",
452		   atomic_read(&tags->active_queues));
453
454	seq_puts(m, "\nbitmap_tags:\n");
455	sbitmap_queue_show(&tags->bitmap_tags, m);
456
457	if (tags->nr_reserved_tags) {
458		seq_puts(m, "\nbreserved_tags:\n");
459		sbitmap_queue_show(&tags->breserved_tags, m);
460	}
461}
462
463static int hctx_tags_show(void *data, struct seq_file *m)
464{
465	struct blk_mq_hw_ctx *hctx = data;
466	struct request_queue *q = hctx->queue;
467	int res;
468
469	res = mutex_lock_interruptible(&q->sysfs_lock);
470	if (res)
471		goto out;
472	if (hctx->tags)
473		blk_mq_debugfs_tags_show(m, hctx->tags);
474	mutex_unlock(&q->sysfs_lock);
475
476out:
477	return res;
478}
479
480static int hctx_tags_bitmap_show(void *data, struct seq_file *m)
481{
482	struct blk_mq_hw_ctx *hctx = data;
483	struct request_queue *q = hctx->queue;
484	int res;
485
486	res = mutex_lock_interruptible(&q->sysfs_lock);
487	if (res)
488		goto out;
489	if (hctx->tags)
490		sbitmap_bitmap_show(&hctx->tags->bitmap_tags.sb, m);
491	mutex_unlock(&q->sysfs_lock);
492
493out:
494	return res;
495}
496
497static int hctx_sched_tags_show(void *data, struct seq_file *m)
498{
499	struct blk_mq_hw_ctx *hctx = data;
500	struct request_queue *q = hctx->queue;
501	int res;
502
503	res = mutex_lock_interruptible(&q->sysfs_lock);
504	if (res)
505		goto out;
506	if (hctx->sched_tags)
507		blk_mq_debugfs_tags_show(m, hctx->sched_tags);
508	mutex_unlock(&q->sysfs_lock);
509
510out:
511	return res;
512}
513
514static int hctx_sched_tags_bitmap_show(void *data, struct seq_file *m)
515{
516	struct blk_mq_hw_ctx *hctx = data;
517	struct request_queue *q = hctx->queue;
518	int res;
519
520	res = mutex_lock_interruptible(&q->sysfs_lock);
521	if (res)
522		goto out;
523	if (hctx->sched_tags)
524		sbitmap_bitmap_show(&hctx->sched_tags->bitmap_tags.sb, m);
525	mutex_unlock(&q->sysfs_lock);
526
527out:
528	return res;
529}
530
531static int hctx_io_poll_show(void *data, struct seq_file *m)
532{
533	struct blk_mq_hw_ctx *hctx = data;
534
535	seq_printf(m, "considered=%lu\n", hctx->poll_considered);
536	seq_printf(m, "invoked=%lu\n", hctx->poll_invoked);
537	seq_printf(m, "success=%lu\n", hctx->poll_success);
538	return 0;
539}
540
541static ssize_t hctx_io_poll_write(void *data, const char __user *buf,
542				  size_t count, loff_t *ppos)
543{
544	struct blk_mq_hw_ctx *hctx = data;
545
546	hctx->poll_considered = hctx->poll_invoked = hctx->poll_success = 0;
547	return count;
548}
549
550static int hctx_dispatched_show(void *data, struct seq_file *m)
551{
552	struct blk_mq_hw_ctx *hctx = data;
553	int i;
554
555	seq_printf(m, "%8u\t%lu\n", 0U, hctx->dispatched[0]);
556
557	for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER - 1; i++) {
558		unsigned int d = 1U << (i - 1);
559
560		seq_printf(m, "%8u\t%lu\n", d, hctx->dispatched[i]);
561	}
562
563	seq_printf(m, "%8u+\t%lu\n", 1U << (i - 1), hctx->dispatched[i]);
564	return 0;
565}
566
567static ssize_t hctx_dispatched_write(void *data, const char __user *buf,
568				     size_t count, loff_t *ppos)
569{
570	struct blk_mq_hw_ctx *hctx = data;
571	int i;
572
573	for (i = 0; i < BLK_MQ_MAX_DISPATCH_ORDER; i++)
574		hctx->dispatched[i] = 0;
575	return count;
576}
577
578static int hctx_queued_show(void *data, struct seq_file *m)
579{
580	struct blk_mq_hw_ctx *hctx = data;
581
582	seq_printf(m, "%lu\n", hctx->queued);
583	return 0;
584}
585
586static ssize_t hctx_queued_write(void *data, const char __user *buf,
587				 size_t count, loff_t *ppos)
588{
589	struct blk_mq_hw_ctx *hctx = data;
590
591	hctx->queued = 0;
592	return count;
593}
594
595static int hctx_run_show(void *data, struct seq_file *m)
596{
597	struct blk_mq_hw_ctx *hctx = data;
598
599	seq_printf(m, "%lu\n", hctx->run);
600	return 0;
601}
602
603static ssize_t hctx_run_write(void *data, const char __user *buf, size_t count,
604			      loff_t *ppos)
605{
606	struct blk_mq_hw_ctx *hctx = data;
607
608	hctx->run = 0;
609	return count;
610}
611
612static int hctx_active_show(void *data, struct seq_file *m)
613{
614	struct blk_mq_hw_ctx *hctx = data;
615
616	seq_printf(m, "%d\n", atomic_read(&hctx->nr_active));
617	return 0;
618}
619
620static int hctx_dispatch_busy_show(void *data, struct seq_file *m)
621{
622	struct blk_mq_hw_ctx *hctx = data;
623
624	seq_printf(m, "%u\n", hctx->dispatch_busy);
625	return 0;
626}
627
628#define CTX_RQ_SEQ_OPS(name, type)					\
629static void *ctx_##name##_rq_list_start(struct seq_file *m, loff_t *pos) \
630	__acquires(&ctx->lock)						\
631{									\
632	struct blk_mq_ctx *ctx = m->private;				\
633									\
634	spin_lock(&ctx->lock);						\
635	return seq_list_start(&ctx->rq_lists[type], *pos);		\
636}									\
637									\
638static void *ctx_##name##_rq_list_next(struct seq_file *m, void *v,	\
639				     loff_t *pos)			\
640{									\
641	struct blk_mq_ctx *ctx = m->private;				\
642									\
643	return seq_list_next(v, &ctx->rq_lists[type], pos);		\
644}									\
645									\
646static void ctx_##name##_rq_list_stop(struct seq_file *m, void *v)	\
647	__releases(&ctx->lock)						\
648{									\
649	struct blk_mq_ctx *ctx = m->private;				\
650									\
651	spin_unlock(&ctx->lock);					\
652}									\
653									\
654static const struct seq_operations ctx_##name##_rq_list_seq_ops = {	\
655	.start	= ctx_##name##_rq_list_start,				\
656	.next	= ctx_##name##_rq_list_next,				\
657	.stop	= ctx_##name##_rq_list_stop,				\
658	.show	= blk_mq_debugfs_rq_show,				\
659}
660
661CTX_RQ_SEQ_OPS(default, HCTX_TYPE_DEFAULT);
662CTX_RQ_SEQ_OPS(read, HCTX_TYPE_READ);
663CTX_RQ_SEQ_OPS(poll, HCTX_TYPE_POLL);
664
665static int ctx_dispatched_show(void *data, struct seq_file *m)
666{
667	struct blk_mq_ctx *ctx = data;
668
669	seq_printf(m, "%lu %lu\n", ctx->rq_dispatched[1], ctx->rq_dispatched[0]);
670	return 0;
671}
672
673static ssize_t ctx_dispatched_write(void *data, const char __user *buf,
674				    size_t count, loff_t *ppos)
675{
676	struct blk_mq_ctx *ctx = data;
677
678	ctx->rq_dispatched[0] = ctx->rq_dispatched[1] = 0;
679	return count;
680}
681
682static int ctx_merged_show(void *data, struct seq_file *m)
683{
684	struct blk_mq_ctx *ctx = data;
685
686	seq_printf(m, "%lu\n", ctx->rq_merged);
687	return 0;
688}
689
690static ssize_t ctx_merged_write(void *data, const char __user *buf,
691				size_t count, loff_t *ppos)
692{
693	struct blk_mq_ctx *ctx = data;
694
695	ctx->rq_merged = 0;
696	return count;
697}
698
699static int ctx_completed_show(void *data, struct seq_file *m)
700{
701	struct blk_mq_ctx *ctx = data;
702
703	seq_printf(m, "%lu %lu\n", ctx->rq_completed[1], ctx->rq_completed[0]);
704	return 0;
705}
706
707static ssize_t ctx_completed_write(void *data, const char __user *buf,
708				   size_t count, loff_t *ppos)
709{
710	struct blk_mq_ctx *ctx = data;
711
712	ctx->rq_completed[0] = ctx->rq_completed[1] = 0;
713	return count;
714}
715
716static int blk_mq_debugfs_show(struct seq_file *m, void *v)
717{
718	const struct blk_mq_debugfs_attr *attr = m->private;
719	void *data = d_inode(m->file->f_path.dentry->d_parent)->i_private;
720
721	return attr->show(data, m);
722}
723
724static ssize_t blk_mq_debugfs_write(struct file *file, const char __user *buf,
725				    size_t count, loff_t *ppos)
726{
727	struct seq_file *m = file->private_data;
728	const struct blk_mq_debugfs_attr *attr = m->private;
729	void *data = d_inode(file->f_path.dentry->d_parent)->i_private;
730
731	/*
732	 * Attributes that only implement .seq_ops are read-only and 'attr' is
733	 * the same with 'data' in this case.
734	 */
735	if (attr == data || !attr->write)
736		return -EPERM;
737
738	return attr->write(data, buf, count, ppos);
739}
740
741static int blk_mq_debugfs_open(struct inode *inode, struct file *file)
742{
743	const struct blk_mq_debugfs_attr *attr = inode->i_private;
744	void *data = d_inode(file->f_path.dentry->d_parent)->i_private;
745	struct seq_file *m;
746	int ret;
747
748	if (attr->seq_ops) {
749		ret = seq_open(file, attr->seq_ops);
750		if (!ret) {
751			m = file->private_data;
752			m->private = data;
753		}
754		return ret;
755	}
756
757	if (WARN_ON_ONCE(!attr->show))
758		return -EPERM;
759
760	return single_open(file, blk_mq_debugfs_show, inode->i_private);
761}
762
763static int blk_mq_debugfs_release(struct inode *inode, struct file *file)
764{
765	const struct blk_mq_debugfs_attr *attr = inode->i_private;
766
767	if (attr->show)
768		return single_release(inode, file);
769
770	return seq_release(inode, file);
771}
772
773static const struct file_operations blk_mq_debugfs_fops = {
774	.open		= blk_mq_debugfs_open,
775	.read		= seq_read,
776	.write		= blk_mq_debugfs_write,
777	.llseek		= seq_lseek,
778	.release	= blk_mq_debugfs_release,
779};
780
781static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_attrs[] = {
782	{"state", 0400, hctx_state_show},
783	{"flags", 0400, hctx_flags_show},
784	{"dispatch", 0400, .seq_ops = &hctx_dispatch_seq_ops},
785	{"busy", 0400, hctx_busy_show},
786	{"ctx_map", 0400, hctx_ctx_map_show},
787	{"tags", 0400, hctx_tags_show},
788	{"tags_bitmap", 0400, hctx_tags_bitmap_show},
789	{"sched_tags", 0400, hctx_sched_tags_show},
790	{"sched_tags_bitmap", 0400, hctx_sched_tags_bitmap_show},
791	{"io_poll", 0600, hctx_io_poll_show, hctx_io_poll_write},
792	{"dispatched", 0600, hctx_dispatched_show, hctx_dispatched_write},
793	{"queued", 0600, hctx_queued_show, hctx_queued_write},
794	{"run", 0600, hctx_run_show, hctx_run_write},
795	{"active", 0400, hctx_active_show},
796	{"dispatch_busy", 0400, hctx_dispatch_busy_show},
797	{"type", 0400, hctx_type_show},
798	{},
799};
800
801static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = {
802	{"default_rq_list", 0400, .seq_ops = &ctx_default_rq_list_seq_ops},
803	{"read_rq_list", 0400, .seq_ops = &ctx_read_rq_list_seq_ops},
804	{"poll_rq_list", 0400, .seq_ops = &ctx_poll_rq_list_seq_ops},
805	{"dispatched", 0600, ctx_dispatched_show, ctx_dispatched_write},
806	{"merged", 0600, ctx_merged_show, ctx_merged_write},
807	{"completed", 0600, ctx_completed_show, ctx_completed_write},
808	{},
809};
810
811static void debugfs_create_files(struct dentry *parent, void *data,
812				 const struct blk_mq_debugfs_attr *attr)
813{
814	if (IS_ERR_OR_NULL(parent))
815		return;
816
817	d_inode(parent)->i_private = data;
818
819	for (; attr->name; attr++)
820		debugfs_create_file(attr->name, attr->mode, parent,
821				    (void *)attr, &blk_mq_debugfs_fops);
822}
823
824void blk_mq_debugfs_register(struct request_queue *q)
825{
826	struct blk_mq_hw_ctx *hctx;
827	int i;
828
829	debugfs_create_files(q->debugfs_dir, q, blk_mq_debugfs_queue_attrs);
830
831	/*
832	 * blk_mq_init_sched() attempted to do this already, but q->debugfs_dir
833	 * didn't exist yet (because we don't know what to name the directory
834	 * until the queue is registered to a gendisk).
835	 */
836	if (q->elevator && !q->sched_debugfs_dir)
837		blk_mq_debugfs_register_sched(q);
838
839	/* Similarly, blk_mq_init_hctx() couldn't do this previously. */
840	queue_for_each_hw_ctx(q, hctx, i) {
841		if (!hctx->debugfs_dir)
842			blk_mq_debugfs_register_hctx(q, hctx);
843		if (q->elevator && !hctx->sched_debugfs_dir)
844			blk_mq_debugfs_register_sched_hctx(q, hctx);
845	}
846
847	if (q->rq_qos) {
848		struct rq_qos *rqos = q->rq_qos;
849
850		while (rqos) {
851			blk_mq_debugfs_register_rqos(rqos);
852			rqos = rqos->next;
853		}
854	}
855}
856
857void blk_mq_debugfs_unregister(struct request_queue *q)
858{
859	q->sched_debugfs_dir = NULL;
860}
861
862static void blk_mq_debugfs_register_ctx(struct blk_mq_hw_ctx *hctx,
863					struct blk_mq_ctx *ctx)
864{
865	struct dentry *ctx_dir;
866	char name[20];
867
868	snprintf(name, sizeof(name), "cpu%u", ctx->cpu);
869	ctx_dir = debugfs_create_dir(name, hctx->debugfs_dir);
870
871	debugfs_create_files(ctx_dir, ctx, blk_mq_debugfs_ctx_attrs);
872}
873
874void blk_mq_debugfs_register_hctx(struct request_queue *q,
875				  struct blk_mq_hw_ctx *hctx)
876{
877	struct blk_mq_ctx *ctx;
878	char name[20];
879	int i;
880
881	snprintf(name, sizeof(name), "hctx%u", hctx->queue_num);
882	hctx->debugfs_dir = debugfs_create_dir(name, q->debugfs_dir);
883
884	debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_attrs);
885
886	hctx_for_each_ctx(hctx, ctx, i)
887		blk_mq_debugfs_register_ctx(hctx, ctx);
888}
889
890void blk_mq_debugfs_unregister_hctx(struct blk_mq_hw_ctx *hctx)
891{
892	debugfs_remove_recursive(hctx->debugfs_dir);
893	hctx->sched_debugfs_dir = NULL;
894	hctx->debugfs_dir = NULL;
895}
896
897void blk_mq_debugfs_register_hctxs(struct request_queue *q)
898{
899	struct blk_mq_hw_ctx *hctx;
900	int i;
901
902	queue_for_each_hw_ctx(q, hctx, i)
903		blk_mq_debugfs_register_hctx(q, hctx);
904}
905
906void blk_mq_debugfs_unregister_hctxs(struct request_queue *q)
907{
908	struct blk_mq_hw_ctx *hctx;
909	int i;
910
911	queue_for_each_hw_ctx(q, hctx, i)
912		blk_mq_debugfs_unregister_hctx(hctx);
913}
914
915void blk_mq_debugfs_register_sched(struct request_queue *q)
916{
917	struct elevator_type *e = q->elevator->type;
918
919	/*
920	 * If the parent directory has not been created yet, return, we will be
921	 * called again later on and the directory/files will be created then.
922	 */
923	if (!q->debugfs_dir)
924		return;
925
926	if (!e->queue_debugfs_attrs)
927		return;
928
929	q->sched_debugfs_dir = debugfs_create_dir("sched", q->debugfs_dir);
930
931	debugfs_create_files(q->sched_debugfs_dir, q, e->queue_debugfs_attrs);
932}
933
934void blk_mq_debugfs_unregister_sched(struct request_queue *q)
935{
936	debugfs_remove_recursive(q->sched_debugfs_dir);
937	q->sched_debugfs_dir = NULL;
938}
939
940void blk_mq_debugfs_unregister_rqos(struct rq_qos *rqos)
941{
942	debugfs_remove_recursive(rqos->debugfs_dir);
943	rqos->debugfs_dir = NULL;
944}
945
946void blk_mq_debugfs_register_rqos(struct rq_qos *rqos)
947{
948	struct request_queue *q = rqos->q;
949	const char *dir_name = rq_qos_id_to_name(rqos->id);
950
951	if (rqos->debugfs_dir || !rqos->ops->debugfs_attrs)
952		return;
953
954	if (!q->rqos_debugfs_dir)
955		q->rqos_debugfs_dir = debugfs_create_dir("rqos",
956							 q->debugfs_dir);
957
958	rqos->debugfs_dir = debugfs_create_dir(dir_name,
959					       rqos->q->rqos_debugfs_dir);
960
961	debugfs_create_files(rqos->debugfs_dir, rqos, rqos->ops->debugfs_attrs);
962}
963
964void blk_mq_debugfs_unregister_queue_rqos(struct request_queue *q)
965{
966	debugfs_remove_recursive(q->rqos_debugfs_dir);
967	q->rqos_debugfs_dir = NULL;
968}
969
970void blk_mq_debugfs_register_sched_hctx(struct request_queue *q,
971					struct blk_mq_hw_ctx *hctx)
972{
973	struct elevator_type *e = q->elevator->type;
974
975	if (!e->hctx_debugfs_attrs)
976		return;
977
978	hctx->sched_debugfs_dir = debugfs_create_dir("sched",
979						     hctx->debugfs_dir);
980	debugfs_create_files(hctx->sched_debugfs_dir, hctx,
981			     e->hctx_debugfs_attrs);
982}
983
984void blk_mq_debugfs_unregister_sched_hctx(struct blk_mq_hw_ctx *hctx)
985{
986	debugfs_remove_recursive(hctx->sched_debugfs_dir);
987	hctx->sched_debugfs_dir = NULL;
988}