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Linux 6.16-rc6
[linux-block.git] / block / blk-sysfs.c
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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Functions related to sysfs handling
4 */
5#include <linux/kernel.h>
6#include <linux/slab.h>
7#include <linux/module.h>
8#include <linux/bio.h>
9#include <linux/blkdev.h>
10#include <linux/backing-dev.h>
11#include <linux/blktrace_api.h>
12#include <linux/debugfs.h>
13
14#include "blk.h"
15#include "blk-mq.h"
16#include "blk-mq-debugfs.h"
17#include "blk-mq-sched.h"
18#include "blk-rq-qos.h"
19#include "blk-wbt.h"
20#include "blk-cgroup.h"
21#include "blk-throttle.h"
22
23struct queue_sysfs_entry {
24 struct attribute attr;
25 ssize_t (*show)(struct gendisk *disk, char *page);
26 ssize_t (*show_limit)(struct gendisk *disk, char *page);
27
28 ssize_t (*store)(struct gendisk *disk, const char *page, size_t count);
29 int (*store_limit)(struct gendisk *disk, const char *page,
30 size_t count, struct queue_limits *lim);
31};
32
33static ssize_t
34queue_var_show(unsigned long var, char *page)
35{
36 return sysfs_emit(page, "%lu\n", var);
37}
38
39static ssize_t
40queue_var_store(unsigned long *var, const char *page, size_t count)
41{
42 int err;
43 unsigned long v;
44
45 err = kstrtoul(page, 10, &v);
46 if (err || v > UINT_MAX)
47 return -EINVAL;
48
49 *var = v;
50
51 return count;
52}
53
54static ssize_t queue_requests_show(struct gendisk *disk, char *page)
55{
56 ssize_t ret;
57
58 mutex_lock(&disk->queue->elevator_lock);
59 ret = queue_var_show(disk->queue->nr_requests, page);
60 mutex_unlock(&disk->queue->elevator_lock);
61 return ret;
62}
63
64static ssize_t
65queue_requests_store(struct gendisk *disk, const char *page, size_t count)
66{
67 unsigned long nr;
68 int ret, err;
69 unsigned int memflags;
70 struct request_queue *q = disk->queue;
71
72 if (!queue_is_mq(q))
73 return -EINVAL;
74
75 ret = queue_var_store(&nr, page, count);
76 if (ret < 0)
77 return ret;
78
79 memflags = blk_mq_freeze_queue(q);
80 mutex_lock(&q->elevator_lock);
81 if (nr < BLKDEV_MIN_RQ)
82 nr = BLKDEV_MIN_RQ;
83
84 err = blk_mq_update_nr_requests(disk->queue, nr);
85 if (err)
86 ret = err;
87 mutex_unlock(&q->elevator_lock);
88 blk_mq_unfreeze_queue(q, memflags);
89 return ret;
90}
91
92static ssize_t queue_ra_show(struct gendisk *disk, char *page)
93{
94 ssize_t ret;
95
96 mutex_lock(&disk->queue->limits_lock);
97 ret = queue_var_show(disk->bdi->ra_pages << (PAGE_SHIFT - 10), page);
98 mutex_unlock(&disk->queue->limits_lock);
99
100 return ret;
101}
102
103static ssize_t
104queue_ra_store(struct gendisk *disk, const char *page, size_t count)
105{
106 unsigned long ra_kb;
107 ssize_t ret;
108 unsigned int memflags;
109 struct request_queue *q = disk->queue;
110
111 ret = queue_var_store(&ra_kb, page, count);
112 if (ret < 0)
113 return ret;
114 /*
115 * ->ra_pages is protected by ->limits_lock because it is usually
116 * calculated from the queue limits by queue_limits_commit_update.
117 */
118 mutex_lock(&q->limits_lock);
119 memflags = blk_mq_freeze_queue(q);
120 disk->bdi->ra_pages = ra_kb >> (PAGE_SHIFT - 10);
121 mutex_unlock(&q->limits_lock);
122 blk_mq_unfreeze_queue(q, memflags);
123
124 return ret;
125}
126
127#define QUEUE_SYSFS_LIMIT_SHOW(_field) \
128static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \
129{ \
130 return queue_var_show(disk->queue->limits._field, page); \
131}
132
133QUEUE_SYSFS_LIMIT_SHOW(max_segments)
134QUEUE_SYSFS_LIMIT_SHOW(max_discard_segments)
135QUEUE_SYSFS_LIMIT_SHOW(max_integrity_segments)
136QUEUE_SYSFS_LIMIT_SHOW(max_segment_size)
137QUEUE_SYSFS_LIMIT_SHOW(max_write_streams)
138QUEUE_SYSFS_LIMIT_SHOW(write_stream_granularity)
139QUEUE_SYSFS_LIMIT_SHOW(logical_block_size)
140QUEUE_SYSFS_LIMIT_SHOW(physical_block_size)
141QUEUE_SYSFS_LIMIT_SHOW(chunk_sectors)
142QUEUE_SYSFS_LIMIT_SHOW(io_min)
143QUEUE_SYSFS_LIMIT_SHOW(io_opt)
144QUEUE_SYSFS_LIMIT_SHOW(discard_granularity)
145QUEUE_SYSFS_LIMIT_SHOW(zone_write_granularity)
146QUEUE_SYSFS_LIMIT_SHOW(virt_boundary_mask)
147QUEUE_SYSFS_LIMIT_SHOW(dma_alignment)
148QUEUE_SYSFS_LIMIT_SHOW(max_open_zones)
149QUEUE_SYSFS_LIMIT_SHOW(max_active_zones)
150QUEUE_SYSFS_LIMIT_SHOW(atomic_write_unit_min)
151QUEUE_SYSFS_LIMIT_SHOW(atomic_write_unit_max)
152
153#define QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(_field) \
154static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \
155{ \
156 return sysfs_emit(page, "%llu\n", \
157 (unsigned long long)disk->queue->limits._field << \
158 SECTOR_SHIFT); \
159}
160
161QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_discard_sectors)
162QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_hw_discard_sectors)
163QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_write_zeroes_sectors)
164QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(atomic_write_max_sectors)
165QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(atomic_write_boundary_sectors)
166QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_zone_append_sectors)
167
168#define QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(_field) \
169static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \
170{ \
171 return queue_var_show(disk->queue->limits._field >> 1, page); \
172}
173
174QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(max_sectors)
175QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(max_hw_sectors)
176
177#define QUEUE_SYSFS_SHOW_CONST(_name, _val) \
178static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \
179{ \
180 return sysfs_emit(page, "%d\n", _val); \
181}
182
183/* deprecated fields */
184QUEUE_SYSFS_SHOW_CONST(discard_zeroes_data, 0)
185QUEUE_SYSFS_SHOW_CONST(write_same_max, 0)
186QUEUE_SYSFS_SHOW_CONST(poll_delay, -1)
187
188static int queue_max_discard_sectors_store(struct gendisk *disk,
189 const char *page, size_t count, struct queue_limits *lim)
190{
191 unsigned long max_discard_bytes;
192 ssize_t ret;
193
194 ret = queue_var_store(&max_discard_bytes, page, count);
195 if (ret < 0)
196 return ret;
197
198 if (max_discard_bytes & (disk->queue->limits.discard_granularity - 1))
199 return -EINVAL;
200
201 if ((max_discard_bytes >> SECTOR_SHIFT) > UINT_MAX)
202 return -EINVAL;
203
204 lim->max_user_discard_sectors = max_discard_bytes >> SECTOR_SHIFT;
205 return 0;
206}
207
208static int
209queue_max_sectors_store(struct gendisk *disk, const char *page, size_t count,
210 struct queue_limits *lim)
211{
212 unsigned long max_sectors_kb;
213 ssize_t ret;
214
215 ret = queue_var_store(&max_sectors_kb, page, count);
216 if (ret < 0)
217 return ret;
218
219 lim->max_user_sectors = max_sectors_kb << 1;
220 return 0;
221}
222
223static ssize_t queue_feature_store(struct gendisk *disk, const char *page,
224 size_t count, struct queue_limits *lim, blk_features_t feature)
225{
226 unsigned long val;
227 ssize_t ret;
228
229 ret = queue_var_store(&val, page, count);
230 if (ret < 0)
231 return ret;
232
233 if (val)
234 lim->features |= feature;
235 else
236 lim->features &= ~feature;
237 return 0;
238}
239
240#define QUEUE_SYSFS_FEATURE(_name, _feature) \
241static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \
242{ \
243 return sysfs_emit(page, "%u\n", \
244 !!(disk->queue->limits.features & _feature)); \
245} \
246static int queue_##_name##_store(struct gendisk *disk, \
247 const char *page, size_t count, struct queue_limits *lim) \
248{ \
249 return queue_feature_store(disk, page, count, lim, _feature); \
250}
251
252QUEUE_SYSFS_FEATURE(rotational, BLK_FEAT_ROTATIONAL)
253QUEUE_SYSFS_FEATURE(add_random, BLK_FEAT_ADD_RANDOM)
254QUEUE_SYSFS_FEATURE(iostats, BLK_FEAT_IO_STAT)
255QUEUE_SYSFS_FEATURE(stable_writes, BLK_FEAT_STABLE_WRITES);
256
257#define QUEUE_SYSFS_FEATURE_SHOW(_name, _feature) \
258static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \
259{ \
260 return sysfs_emit(page, "%u\n", \
261 !!(disk->queue->limits.features & _feature)); \
262}
263
264QUEUE_SYSFS_FEATURE_SHOW(fua, BLK_FEAT_FUA);
265QUEUE_SYSFS_FEATURE_SHOW(dax, BLK_FEAT_DAX);
266
267static ssize_t queue_poll_show(struct gendisk *disk, char *page)
268{
269 if (queue_is_mq(disk->queue))
270 return sysfs_emit(page, "%u\n", blk_mq_can_poll(disk->queue));
271
272 return sysfs_emit(page, "%u\n",
273 !!(disk->queue->limits.features & BLK_FEAT_POLL));
274}
275
276static ssize_t queue_zoned_show(struct gendisk *disk, char *page)
277{
278 if (blk_queue_is_zoned(disk->queue))
279 return sysfs_emit(page, "host-managed\n");
280 return sysfs_emit(page, "none\n");
281}
282
283static ssize_t queue_nr_zones_show(struct gendisk *disk, char *page)
284{
285 return queue_var_show(disk_nr_zones(disk), page);
286}
287
288static ssize_t queue_iostats_passthrough_show(struct gendisk *disk, char *page)
289{
290 return queue_var_show(!!blk_queue_passthrough_stat(disk->queue), page);
291}
292
293static int queue_iostats_passthrough_store(struct gendisk *disk,
294 const char *page, size_t count, struct queue_limits *lim)
295{
296 unsigned long ios;
297 ssize_t ret;
298
299 ret = queue_var_store(&ios, page, count);
300 if (ret < 0)
301 return ret;
302
303 if (ios)
304 lim->flags |= BLK_FLAG_IOSTATS_PASSTHROUGH;
305 else
306 lim->flags &= ~BLK_FLAG_IOSTATS_PASSTHROUGH;
307 return 0;
308}
309
310static ssize_t queue_nomerges_show(struct gendisk *disk, char *page)
311{
312 return queue_var_show((blk_queue_nomerges(disk->queue) << 1) |
313 blk_queue_noxmerges(disk->queue), page);
314}
315
316static ssize_t queue_nomerges_store(struct gendisk *disk, const char *page,
317 size_t count)
318{
319 unsigned long nm;
320 unsigned int memflags;
321 struct request_queue *q = disk->queue;
322 ssize_t ret = queue_var_store(&nm, page, count);
323
324 if (ret < 0)
325 return ret;
326
327 memflags = blk_mq_freeze_queue(q);
328 blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
329 blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
330 if (nm == 2)
331 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, q);
332 else if (nm)
333 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
334 blk_mq_unfreeze_queue(q, memflags);
335
336 return ret;
337}
338
339static ssize_t queue_rq_affinity_show(struct gendisk *disk, char *page)
340{
341 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &disk->queue->queue_flags);
342 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &disk->queue->queue_flags);
343
344 return queue_var_show(set << force, page);
345}
346
347static ssize_t
348queue_rq_affinity_store(struct gendisk *disk, const char *page, size_t count)
349{
350 ssize_t ret = -EINVAL;
351#ifdef CONFIG_SMP
352 struct request_queue *q = disk->queue;
353 unsigned long val;
354 unsigned int memflags;
355
356 ret = queue_var_store(&val, page, count);
357 if (ret < 0)
358 return ret;
359
360 /*
361 * Here we update two queue flags each using atomic bitops, although
362 * updating two flags isn't atomic it should be harmless as those flags
363 * are accessed individually using atomic test_bit operation. So we
364 * don't grab any lock while updating these flags.
365 */
366 memflags = blk_mq_freeze_queue(q);
367 if (val == 2) {
368 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
369 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
370 } else if (val == 1) {
371 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
372 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
373 } else if (val == 0) {
374 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
375 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
376 }
377 blk_mq_unfreeze_queue(q, memflags);
378#endif
379 return ret;
380}
381
382static ssize_t queue_poll_delay_store(struct gendisk *disk, const char *page,
383 size_t count)
384{
385 return count;
386}
387
388static ssize_t queue_poll_store(struct gendisk *disk, const char *page,
389 size_t count)
390{
391 unsigned int memflags;
392 ssize_t ret = count;
393 struct request_queue *q = disk->queue;
394
395 memflags = blk_mq_freeze_queue(q);
396 if (!(q->limits.features & BLK_FEAT_POLL)) {
397 ret = -EINVAL;
398 goto out;
399 }
400
401 pr_info_ratelimited("writes to the poll attribute are ignored.\n");
402 pr_info_ratelimited("please use driver specific parameters instead.\n");
403out:
404 blk_mq_unfreeze_queue(q, memflags);
405 return ret;
406}
407
408static ssize_t queue_io_timeout_show(struct gendisk *disk, char *page)
409{
410 return sysfs_emit(page, "%u\n",
411 jiffies_to_msecs(READ_ONCE(disk->queue->rq_timeout)));
412}
413
414static ssize_t queue_io_timeout_store(struct gendisk *disk, const char *page,
415 size_t count)
416{
417 unsigned int val, memflags;
418 int err;
419 struct request_queue *q = disk->queue;
420
421 err = kstrtou32(page, 10, &val);
422 if (err || val == 0)
423 return -EINVAL;
424
425 memflags = blk_mq_freeze_queue(q);
426 blk_queue_rq_timeout(q, msecs_to_jiffies(val));
427 blk_mq_unfreeze_queue(q, memflags);
428
429 return count;
430}
431
432static ssize_t queue_wc_show(struct gendisk *disk, char *page)
433{
434 if (blk_queue_write_cache(disk->queue))
435 return sysfs_emit(page, "write back\n");
436 return sysfs_emit(page, "write through\n");
437}
438
439static int queue_wc_store(struct gendisk *disk, const char *page,
440 size_t count, struct queue_limits *lim)
441{
442 bool disable;
443
444 if (!strncmp(page, "write back", 10)) {
445 disable = false;
446 } else if (!strncmp(page, "write through", 13) ||
447 !strncmp(page, "none", 4)) {
448 disable = true;
449 } else {
450 return -EINVAL;
451 }
452
453 if (disable)
454 lim->flags |= BLK_FLAG_WRITE_CACHE_DISABLED;
455 else
456 lim->flags &= ~BLK_FLAG_WRITE_CACHE_DISABLED;
457 return 0;
458}
459
460#define QUEUE_RO_ENTRY(_prefix, _name) \
461static struct queue_sysfs_entry _prefix##_entry = { \
462 .attr = { .name = _name, .mode = 0444 }, \
463 .show = _prefix##_show, \
464};
465
466#define QUEUE_RW_ENTRY(_prefix, _name) \
467static struct queue_sysfs_entry _prefix##_entry = { \
468 .attr = { .name = _name, .mode = 0644 }, \
469 .show = _prefix##_show, \
470 .store = _prefix##_store, \
471};
472
473#define QUEUE_LIM_RO_ENTRY(_prefix, _name) \
474static struct queue_sysfs_entry _prefix##_entry = { \
475 .attr = { .name = _name, .mode = 0444 }, \
476 .show_limit = _prefix##_show, \
477}
478
479#define QUEUE_LIM_RW_ENTRY(_prefix, _name) \
480static struct queue_sysfs_entry _prefix##_entry = { \
481 .attr = { .name = _name, .mode = 0644 }, \
482 .show_limit = _prefix##_show, \
483 .store_limit = _prefix##_store, \
484}
485
486QUEUE_RW_ENTRY(queue_requests, "nr_requests");
487QUEUE_RW_ENTRY(queue_ra, "read_ahead_kb");
488QUEUE_LIM_RW_ENTRY(queue_max_sectors, "max_sectors_kb");
489QUEUE_LIM_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb");
490QUEUE_LIM_RO_ENTRY(queue_max_segments, "max_segments");
491QUEUE_LIM_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments");
492QUEUE_LIM_RO_ENTRY(queue_max_segment_size, "max_segment_size");
493QUEUE_LIM_RO_ENTRY(queue_max_write_streams, "max_write_streams");
494QUEUE_LIM_RO_ENTRY(queue_write_stream_granularity, "write_stream_granularity");
495QUEUE_RW_ENTRY(elv_iosched, "scheduler");
496
497QUEUE_LIM_RO_ENTRY(queue_logical_block_size, "logical_block_size");
498QUEUE_LIM_RO_ENTRY(queue_physical_block_size, "physical_block_size");
499QUEUE_LIM_RO_ENTRY(queue_chunk_sectors, "chunk_sectors");
500QUEUE_LIM_RO_ENTRY(queue_io_min, "minimum_io_size");
501QUEUE_LIM_RO_ENTRY(queue_io_opt, "optimal_io_size");
502
503QUEUE_LIM_RO_ENTRY(queue_max_discard_segments, "max_discard_segments");
504QUEUE_LIM_RO_ENTRY(queue_discard_granularity, "discard_granularity");
505QUEUE_LIM_RO_ENTRY(queue_max_hw_discard_sectors, "discard_max_hw_bytes");
506QUEUE_LIM_RW_ENTRY(queue_max_discard_sectors, "discard_max_bytes");
507QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data");
508
509QUEUE_LIM_RO_ENTRY(queue_atomic_write_max_sectors, "atomic_write_max_bytes");
510QUEUE_LIM_RO_ENTRY(queue_atomic_write_boundary_sectors,
511 "atomic_write_boundary_bytes");
512QUEUE_LIM_RO_ENTRY(queue_atomic_write_unit_max, "atomic_write_unit_max_bytes");
513QUEUE_LIM_RO_ENTRY(queue_atomic_write_unit_min, "atomic_write_unit_min_bytes");
514
515QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes");
516QUEUE_LIM_RO_ENTRY(queue_max_write_zeroes_sectors, "write_zeroes_max_bytes");
517QUEUE_LIM_RO_ENTRY(queue_max_zone_append_sectors, "zone_append_max_bytes");
518QUEUE_LIM_RO_ENTRY(queue_zone_write_granularity, "zone_write_granularity");
519
520QUEUE_LIM_RO_ENTRY(queue_zoned, "zoned");
521QUEUE_RO_ENTRY(queue_nr_zones, "nr_zones");
522QUEUE_LIM_RO_ENTRY(queue_max_open_zones, "max_open_zones");
523QUEUE_LIM_RO_ENTRY(queue_max_active_zones, "max_active_zones");
524
525QUEUE_RW_ENTRY(queue_nomerges, "nomerges");
526QUEUE_LIM_RW_ENTRY(queue_iostats_passthrough, "iostats_passthrough");
527QUEUE_RW_ENTRY(queue_rq_affinity, "rq_affinity");
528QUEUE_RW_ENTRY(queue_poll, "io_poll");
529QUEUE_RW_ENTRY(queue_poll_delay, "io_poll_delay");
530QUEUE_LIM_RW_ENTRY(queue_wc, "write_cache");
531QUEUE_LIM_RO_ENTRY(queue_fua, "fua");
532QUEUE_LIM_RO_ENTRY(queue_dax, "dax");
533QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout");
534QUEUE_LIM_RO_ENTRY(queue_virt_boundary_mask, "virt_boundary_mask");
535QUEUE_LIM_RO_ENTRY(queue_dma_alignment, "dma_alignment");
536
537/* legacy alias for logical_block_size: */
538static struct queue_sysfs_entry queue_hw_sector_size_entry = {
539 .attr = {.name = "hw_sector_size", .mode = 0444 },
540 .show_limit = queue_logical_block_size_show,
541};
542
543QUEUE_LIM_RW_ENTRY(queue_rotational, "rotational");
544QUEUE_LIM_RW_ENTRY(queue_iostats, "iostats");
545QUEUE_LIM_RW_ENTRY(queue_add_random, "add_random");
546QUEUE_LIM_RW_ENTRY(queue_stable_writes, "stable_writes");
547
548#ifdef CONFIG_BLK_WBT
549static ssize_t queue_var_store64(s64 *var, const char *page)
550{
551 int err;
552 s64 v;
553
554 err = kstrtos64(page, 10, &v);
555 if (err < 0)
556 return err;
557
558 *var = v;
559 return 0;
560}
561
562static ssize_t queue_wb_lat_show(struct gendisk *disk, char *page)
563{
564 ssize_t ret;
565 struct request_queue *q = disk->queue;
566
567 mutex_lock(&disk->rqos_state_mutex);
568 if (!wbt_rq_qos(q)) {
569 ret = -EINVAL;
570 goto out;
571 }
572
573 if (wbt_disabled(q)) {
574 ret = sysfs_emit(page, "0\n");
575 goto out;
576 }
577
578 ret = sysfs_emit(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000));
579out:
580 mutex_unlock(&disk->rqos_state_mutex);
581 return ret;
582}
583
584static ssize_t queue_wb_lat_store(struct gendisk *disk, const char *page,
585 size_t count)
586{
587 struct request_queue *q = disk->queue;
588 struct rq_qos *rqos;
589 ssize_t ret;
590 s64 val;
591 unsigned int memflags;
592
593 ret = queue_var_store64(&val, page);
594 if (ret < 0)
595 return ret;
596 if (val < -1)
597 return -EINVAL;
598
599 memflags = blk_mq_freeze_queue(q);
600
601 rqos = wbt_rq_qos(q);
602 if (!rqos) {
603 ret = wbt_init(disk);
604 if (ret)
605 goto out;
606 }
607
608 ret = count;
609 if (val == -1)
610 val = wbt_default_latency_nsec(q);
611 else if (val >= 0)
612 val *= 1000ULL;
613
614 if (wbt_get_min_lat(q) == val)
615 goto out;
616
617 /*
618 * Ensure that the queue is idled, in case the latency update
619 * ends up either enabling or disabling wbt completely. We can't
620 * have IO inflight if that happens.
621 */
622 blk_mq_quiesce_queue(q);
623
624 mutex_lock(&disk->rqos_state_mutex);
625 wbt_set_min_lat(q, val);
626 mutex_unlock(&disk->rqos_state_mutex);
627
628 blk_mq_unquiesce_queue(q);
629out:
630 blk_mq_unfreeze_queue(q, memflags);
631
632 return ret;
633}
634
635QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec");
636#endif
637
638/* Common attributes for bio-based and request-based queues. */
639static struct attribute *queue_attrs[] = {
640 /*
641 * Attributes which are protected with q->limits_lock.
642 */
643 &queue_max_hw_sectors_entry.attr,
644 &queue_max_sectors_entry.attr,
645 &queue_max_segments_entry.attr,
646 &queue_max_discard_segments_entry.attr,
647 &queue_max_integrity_segments_entry.attr,
648 &queue_max_segment_size_entry.attr,
649 &queue_max_write_streams_entry.attr,
650 &queue_write_stream_granularity_entry.attr,
651 &queue_hw_sector_size_entry.attr,
652 &queue_logical_block_size_entry.attr,
653 &queue_physical_block_size_entry.attr,
654 &queue_chunk_sectors_entry.attr,
655 &queue_io_min_entry.attr,
656 &queue_io_opt_entry.attr,
657 &queue_discard_granularity_entry.attr,
658 &queue_max_discard_sectors_entry.attr,
659 &queue_max_hw_discard_sectors_entry.attr,
660 &queue_atomic_write_max_sectors_entry.attr,
661 &queue_atomic_write_boundary_sectors_entry.attr,
662 &queue_atomic_write_unit_min_entry.attr,
663 &queue_atomic_write_unit_max_entry.attr,
664 &queue_max_write_zeroes_sectors_entry.attr,
665 &queue_max_zone_append_sectors_entry.attr,
666 &queue_zone_write_granularity_entry.attr,
667 &queue_rotational_entry.attr,
668 &queue_zoned_entry.attr,
669 &queue_max_open_zones_entry.attr,
670 &queue_max_active_zones_entry.attr,
671 &queue_iostats_passthrough_entry.attr,
672 &queue_iostats_entry.attr,
673 &queue_stable_writes_entry.attr,
674 &queue_add_random_entry.attr,
675 &queue_wc_entry.attr,
676 &queue_fua_entry.attr,
677 &queue_dax_entry.attr,
678 &queue_virt_boundary_mask_entry.attr,
679 &queue_dma_alignment_entry.attr,
680 &queue_ra_entry.attr,
681
682 /*
683 * Attributes which don't require locking.
684 */
685 &queue_discard_zeroes_data_entry.attr,
686 &queue_write_same_max_entry.attr,
687 &queue_nr_zones_entry.attr,
688 &queue_nomerges_entry.attr,
689 &queue_poll_entry.attr,
690 &queue_poll_delay_entry.attr,
691
692 NULL,
693};
694
695/* Request-based queue attributes that are not relevant for bio-based queues. */
696static struct attribute *blk_mq_queue_attrs[] = {
697 /*
698 * Attributes which require some form of locking other than
699 * q->sysfs_lock.
700 */
701 &elv_iosched_entry.attr,
702 &queue_requests_entry.attr,
703#ifdef CONFIG_BLK_WBT
704 &queue_wb_lat_entry.attr,
705#endif
706 /*
707 * Attributes which don't require locking.
708 */
709 &queue_rq_affinity_entry.attr,
710 &queue_io_timeout_entry.attr,
711
712 NULL,
713};
714
715static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr,
716 int n)
717{
718 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj);
719 struct request_queue *q = disk->queue;
720
721 if ((attr == &queue_max_open_zones_entry.attr ||
722 attr == &queue_max_active_zones_entry.attr) &&
723 !blk_queue_is_zoned(q))
724 return 0;
725
726 return attr->mode;
727}
728
729static umode_t blk_mq_queue_attr_visible(struct kobject *kobj,
730 struct attribute *attr, int n)
731{
732 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj);
733 struct request_queue *q = disk->queue;
734
735 if (!queue_is_mq(q))
736 return 0;
737
738 if (attr == &queue_io_timeout_entry.attr && !q->mq_ops->timeout)
739 return 0;
740
741 return attr->mode;
742}
743
744static struct attribute_group queue_attr_group = {
745 .attrs = queue_attrs,
746 .is_visible = queue_attr_visible,
747};
748
749static struct attribute_group blk_mq_queue_attr_group = {
750 .attrs = blk_mq_queue_attrs,
751 .is_visible = blk_mq_queue_attr_visible,
752};
753
754#define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
755
756static ssize_t
757queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
758{
759 struct queue_sysfs_entry *entry = to_queue(attr);
760 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj);
761
762 if (!entry->show && !entry->show_limit)
763 return -EIO;
764
765 if (entry->show_limit) {
766 ssize_t res;
767
768 mutex_lock(&disk->queue->limits_lock);
769 res = entry->show_limit(disk, page);
770 mutex_unlock(&disk->queue->limits_lock);
771 return res;
772 }
773
774 return entry->show(disk, page);
775}
776
777static ssize_t
778queue_attr_store(struct kobject *kobj, struct attribute *attr,
779 const char *page, size_t length)
780{
781 struct queue_sysfs_entry *entry = to_queue(attr);
782 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj);
783 struct request_queue *q = disk->queue;
784
785 if (!entry->store_limit && !entry->store)
786 return -EIO;
787
788 if (entry->store_limit) {
789 ssize_t res;
790
791 struct queue_limits lim = queue_limits_start_update(q);
792
793 res = entry->store_limit(disk, page, length, &lim);
794 if (res < 0) {
795 queue_limits_cancel_update(q);
796 return res;
797 }
798
799 res = queue_limits_commit_update_frozen(q, &lim);
800 if (res)
801 return res;
802 return length;
803 }
804
805 return entry->store(disk, page, length);
806}
807
808static const struct sysfs_ops queue_sysfs_ops = {
809 .show = queue_attr_show,
810 .store = queue_attr_store,
811};
812
813static const struct attribute_group *blk_queue_attr_groups[] = {
814 &queue_attr_group,
815 &blk_mq_queue_attr_group,
816 NULL
817};
818
819static void blk_queue_release(struct kobject *kobj)
820{
821 /* nothing to do here, all data is associated with the parent gendisk */
822}
823
824static const struct kobj_type blk_queue_ktype = {
825 .default_groups = blk_queue_attr_groups,
826 .sysfs_ops = &queue_sysfs_ops,
827 .release = blk_queue_release,
828};
829
830static void blk_debugfs_remove(struct gendisk *disk)
831{
832 struct request_queue *q = disk->queue;
833
834 mutex_lock(&q->debugfs_mutex);
835 blk_trace_shutdown(q);
836 debugfs_remove_recursive(q->debugfs_dir);
837 q->debugfs_dir = NULL;
838 q->sched_debugfs_dir = NULL;
839 q->rqos_debugfs_dir = NULL;
840 mutex_unlock(&q->debugfs_mutex);
841}
842
843/**
844 * blk_register_queue - register a block layer queue with sysfs
845 * @disk: Disk of which the request queue should be registered with sysfs.
846 */
847int blk_register_queue(struct gendisk *disk)
848{
849 struct request_queue *q = disk->queue;
850 int ret;
851
852 kobject_init(&disk->queue_kobj, &blk_queue_ktype);
853 ret = kobject_add(&disk->queue_kobj, &disk_to_dev(disk)->kobj, "queue");
854 if (ret < 0)
855 goto out_put_queue_kobj;
856
857 if (queue_is_mq(q)) {
858 ret = blk_mq_sysfs_register(disk);
859 if (ret)
860 goto out_put_queue_kobj;
861 }
862 mutex_lock(&q->sysfs_lock);
863
864 mutex_lock(&q->debugfs_mutex);
865 q->debugfs_dir = debugfs_create_dir(disk->disk_name, blk_debugfs_root);
866 if (queue_is_mq(q))
867 blk_mq_debugfs_register(q);
868 mutex_unlock(&q->debugfs_mutex);
869
870 ret = disk_register_independent_access_ranges(disk);
871 if (ret)
872 goto out_debugfs_remove;
873
874 ret = blk_crypto_sysfs_register(disk);
875 if (ret)
876 goto out_unregister_ia_ranges;
877
878 if (queue_is_mq(q))
879 elevator_set_default(q);
880 wbt_enable_default(disk);
881
882 blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q);
883
884 /* Now everything is ready and send out KOBJ_ADD uevent */
885 kobject_uevent(&disk->queue_kobj, KOBJ_ADD);
886 if (q->elevator)
887 kobject_uevent(&q->elevator->kobj, KOBJ_ADD);
888 mutex_unlock(&q->sysfs_lock);
889
890 /*
891 * SCSI probing may synchronously create and destroy a lot of
892 * request_queues for non-existent devices. Shutting down a fully
893 * functional queue takes measureable wallclock time as RCU grace
894 * periods are involved. To avoid excessive latency in these
895 * cases, a request_queue starts out in a degraded mode which is
896 * faster to shut down and is made fully functional here as
897 * request_queues for non-existent devices never get registered.
898 */
899 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q);
900 percpu_ref_switch_to_percpu(&q->q_usage_counter);
901
902 return ret;
903
904out_unregister_ia_ranges:
905 disk_unregister_independent_access_ranges(disk);
906out_debugfs_remove:
907 blk_debugfs_remove(disk);
908 mutex_unlock(&q->sysfs_lock);
909 if (queue_is_mq(q))
910 blk_mq_sysfs_unregister(disk);
911out_put_queue_kobj:
912 kobject_put(&disk->queue_kobj);
913 return ret;
914}
915
916/**
917 * blk_unregister_queue - counterpart of blk_register_queue()
918 * @disk: Disk of which the request queue should be unregistered from sysfs.
919 *
920 * Note: the caller is responsible for guaranteeing that this function is called
921 * after blk_register_queue() has finished.
922 */
923void blk_unregister_queue(struct gendisk *disk)
924{
925 struct request_queue *q = disk->queue;
926
927 if (WARN_ON(!q))
928 return;
929
930 /* Return early if disk->queue was never registered. */
931 if (!blk_queue_registered(q))
932 return;
933
934 /*
935 * Since sysfs_remove_dir() prevents adding new directory entries
936 * before removal of existing entries starts, protect against
937 * concurrent elv_iosched_store() calls.
938 */
939 mutex_lock(&q->sysfs_lock);
940 blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q);
941 mutex_unlock(&q->sysfs_lock);
942
943 /*
944 * Remove the sysfs attributes before unregistering the queue data
945 * structures that can be modified through sysfs.
946 */
947 if (queue_is_mq(q))
948 blk_mq_sysfs_unregister(disk);
949 blk_crypto_sysfs_unregister(disk);
950
951 mutex_lock(&q->sysfs_lock);
952 disk_unregister_independent_access_ranges(disk);
953 mutex_unlock(&q->sysfs_lock);
954
955 /* Now that we've deleted all child objects, we can delete the queue. */
956 kobject_uevent(&disk->queue_kobj, KOBJ_REMOVE);
957 kobject_del(&disk->queue_kobj);
958
959 if (queue_is_mq(q))
960 elevator_set_none(q);
961
962 blk_debugfs_remove(disk);
963}
Linux 6.x block layer and io_uring tree(s)