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