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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/*
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/backing-dev.h>
10#include <linux/blktrace_api.h>
11#include <linux/blk-mq.h>
12#include <linux/blk-cgroup.h>
13
14#include "blk.h"
15#include "blk-mq.h"
16
17struct queue_sysfs_entry {
18 struct attribute attr;
19 ssize_t (*show)(struct request_queue *, char *);
20 ssize_t (*store)(struct request_queue *, const char *, size_t);
21};
22
23static ssize_t
24queue_var_show(unsigned long var, char *page)
25{
26 return sprintf(page, "%lu\n", var);
27}
28
29static ssize_t
30queue_var_store(unsigned long *var, const char *page, size_t count)
31{
32 int err;
33 unsigned long v;
34
35 err = kstrtoul(page, 10, &v);
36 if (err || v > UINT_MAX)
37 return -EINVAL;
38
39 *var = v;
40
41 return count;
42}
43
44static ssize_t queue_requests_show(struct request_queue *q, char *page)
45{
46 return queue_var_show(q->nr_requests, (page));
47}
48
49static ssize_t
50queue_requests_store(struct request_queue *q, const char *page, size_t count)
51{
52 unsigned long nr;
53 int ret, err;
54
55 if (!q->request_fn && !q->mq_ops)
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 if (q->request_fn)
66 err = blk_update_nr_requests(q, nr);
67 else
68 err = blk_mq_update_nr_requests(q, nr);
69
70 if (err)
71 return err;
72
73 return ret;
74}
75
76static ssize_t queue_ra_show(struct request_queue *q, char *page)
77{
78 unsigned long ra_kb = q->backing_dev_info.ra_pages <<
79 (PAGE_SHIFT - 10);
80
81 return queue_var_show(ra_kb, (page));
82}
83
84static ssize_t
85queue_ra_store(struct request_queue *q, const char *page, size_t count)
86{
87 unsigned long ra_kb;
88 ssize_t ret = queue_var_store(&ra_kb, page, count);
89
90 if (ret < 0)
91 return ret;
92
93 q->backing_dev_info.ra_pages = ra_kb >> (PAGE_SHIFT - 10);
94
95 return ret;
96}
97
98static ssize_t queue_max_sectors_show(struct request_queue *q, char *page)
99{
100 int max_sectors_kb = queue_max_sectors(q) >> 1;
101
102 return queue_var_show(max_sectors_kb, (page));
103}
104
105static ssize_t queue_max_segments_show(struct request_queue *q, char *page)
106{
107 return queue_var_show(queue_max_segments(q), (page));
108}
109
110static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page)
111{
112 return queue_var_show(q->limits.max_integrity_segments, (page));
113}
114
115static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page)
116{
117 if (blk_queue_cluster(q))
118 return queue_var_show(queue_max_segment_size(q), (page));
119
120 return queue_var_show(PAGE_SIZE, (page));
121}
122
123static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page)
124{
125 return queue_var_show(queue_logical_block_size(q), page);
126}
127
128static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page)
129{
130 return queue_var_show(queue_physical_block_size(q), page);
131}
132
133static ssize_t queue_io_min_show(struct request_queue *q, char *page)
134{
135 return queue_var_show(queue_io_min(q), page);
136}
137
138static ssize_t queue_io_opt_show(struct request_queue *q, char *page)
139{
140 return queue_var_show(queue_io_opt(q), page);
141}
142
143static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page)
144{
145 return queue_var_show(q->limits.discard_granularity, page);
146}
147
148static ssize_t queue_discard_max_hw_show(struct request_queue *q, char *page)
149{
150
151 return sprintf(page, "%llu\n",
152 (unsigned long long)q->limits.max_hw_discard_sectors << 9);
153}
154
155static ssize_t queue_discard_max_show(struct request_queue *q, char *page)
156{
157 return sprintf(page, "%llu\n",
158 (unsigned long long)q->limits.max_discard_sectors << 9);
159}
160
161static ssize_t queue_discard_max_store(struct request_queue *q,
162 const char *page, size_t count)
163{
164 unsigned long max_discard;
165 ssize_t ret = queue_var_store(&max_discard, page, count);
166
167 if (ret < 0)
168 return ret;
169
170 if (max_discard & (q->limits.discard_granularity - 1))
171 return -EINVAL;
172
173 max_discard >>= 9;
174 if (max_discard > UINT_MAX)
175 return -EINVAL;
176
177 if (max_discard > q->limits.max_hw_discard_sectors)
178 max_discard = q->limits.max_hw_discard_sectors;
179
180 q->limits.max_discard_sectors = max_discard;
181 return ret;
182}
183
184static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page)
185{
186 return queue_var_show(queue_discard_zeroes_data(q), page);
187}
188
189static ssize_t queue_write_same_max_show(struct request_queue *q, char *page)
190{
191 return sprintf(page, "%llu\n",
192 (unsigned long long)q->limits.max_write_same_sectors << 9);
193}
194
195
196static ssize_t
197queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
198{
199 unsigned long max_sectors_kb,
200 max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
201 page_kb = 1 << (PAGE_SHIFT - 10);
202 ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
203
204 if (ret < 0)
205 return ret;
206
207 max_hw_sectors_kb = min_not_zero(max_hw_sectors_kb, (unsigned long)
208 q->limits.max_dev_sectors >> 1);
209
210 if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb)
211 return -EINVAL;
212
213 spin_lock_irq(q->queue_lock);
214 q->limits.max_sectors = max_sectors_kb << 1;
215 spin_unlock_irq(q->queue_lock);
216
217 return ret;
218}
219
220static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page)
221{
222 int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
223
224 return queue_var_show(max_hw_sectors_kb, (page));
225}
226
227#define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \
228static ssize_t \
229queue_show_##name(struct request_queue *q, char *page) \
230{ \
231 int bit; \
232 bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \
233 return queue_var_show(neg ? !bit : bit, page); \
234} \
235static ssize_t \
236queue_store_##name(struct request_queue *q, const char *page, size_t count) \
237{ \
238 unsigned long val; \
239 ssize_t ret; \
240 ret = queue_var_store(&val, page, count); \
241 if (ret < 0) \
242 return ret; \
243 if (neg) \
244 val = !val; \
245 \
246 spin_lock_irq(q->queue_lock); \
247 if (val) \
248 queue_flag_set(QUEUE_FLAG_##flag, q); \
249 else \
250 queue_flag_clear(QUEUE_FLAG_##flag, q); \
251 spin_unlock_irq(q->queue_lock); \
252 return ret; \
253}
254
255QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
256QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
257QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
258#undef QUEUE_SYSFS_BIT_FNS
259
260static ssize_t queue_nomerges_show(struct request_queue *q, char *page)
261{
262 return queue_var_show((blk_queue_nomerges(q) << 1) |
263 blk_queue_noxmerges(q), page);
264}
265
266static ssize_t queue_nomerges_store(struct request_queue *q, const char *page,
267 size_t count)
268{
269 unsigned long nm;
270 ssize_t ret = queue_var_store(&nm, page, count);
271
272 if (ret < 0)
273 return ret;
274
275 spin_lock_irq(q->queue_lock);
276 queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
277 queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
278 if (nm == 2)
279 queue_flag_set(QUEUE_FLAG_NOMERGES, q);
280 else if (nm)
281 queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
282 spin_unlock_irq(q->queue_lock);
283
284 return ret;
285}
286
287static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page)
288{
289 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
290 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags);
291
292 return queue_var_show(set << force, page);
293}
294
295static ssize_t
296queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
297{
298 ssize_t ret = -EINVAL;
299#ifdef CONFIG_SMP
300 unsigned long val;
301
302 ret = queue_var_store(&val, page, count);
303 if (ret < 0)
304 return ret;
305
306 spin_lock_irq(q->queue_lock);
307 if (val == 2) {
308 queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
309 queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
310 } else if (val == 1) {
311 queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
312 queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
313 } else if (val == 0) {
314 queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
315 queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
316 }
317 spin_unlock_irq(q->queue_lock);
318#endif
319 return ret;
320}
321
322static ssize_t queue_poll_show(struct request_queue *q, char *page)
323{
324 return queue_var_show(test_bit(QUEUE_FLAG_POLL, &q->queue_flags), page);
325}
326
327static ssize_t queue_poll_store(struct request_queue *q, const char *page,
328 size_t count)
329{
330 unsigned long poll_on;
331 ssize_t ret;
332
333 if (!q->mq_ops || !q->mq_ops->poll)
334 return -EINVAL;
335
336 ret = queue_var_store(&poll_on, page, count);
337 if (ret < 0)
338 return ret;
339
340 spin_lock_irq(q->queue_lock);
341 if (poll_on)
342 queue_flag_set(QUEUE_FLAG_POLL, q);
343 else
344 queue_flag_clear(QUEUE_FLAG_POLL, q);
345 spin_unlock_irq(q->queue_lock);
346
347 return ret;
348}
349
350static struct queue_sysfs_entry queue_requests_entry = {
351 .attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR },
352 .show = queue_requests_show,
353 .store = queue_requests_store,
354};
355
356static struct queue_sysfs_entry queue_ra_entry = {
357 .attr = {.name = "read_ahead_kb", .mode = S_IRUGO | S_IWUSR },
358 .show = queue_ra_show,
359 .store = queue_ra_store,
360};
361
362static struct queue_sysfs_entry queue_max_sectors_entry = {
363 .attr = {.name = "max_sectors_kb", .mode = S_IRUGO | S_IWUSR },
364 .show = queue_max_sectors_show,
365 .store = queue_max_sectors_store,
366};
367
368static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
369 .attr = {.name = "max_hw_sectors_kb", .mode = S_IRUGO },
370 .show = queue_max_hw_sectors_show,
371};
372
373static struct queue_sysfs_entry queue_max_segments_entry = {
374 .attr = {.name = "max_segments", .mode = S_IRUGO },
375 .show = queue_max_segments_show,
376};
377
378static struct queue_sysfs_entry queue_max_integrity_segments_entry = {
379 .attr = {.name = "max_integrity_segments", .mode = S_IRUGO },
380 .show = queue_max_integrity_segments_show,
381};
382
383static struct queue_sysfs_entry queue_max_segment_size_entry = {
384 .attr = {.name = "max_segment_size", .mode = S_IRUGO },
385 .show = queue_max_segment_size_show,
386};
387
388static struct queue_sysfs_entry queue_iosched_entry = {
389 .attr = {.name = "scheduler", .mode = S_IRUGO | S_IWUSR },
390 .show = elv_iosched_show,
391 .store = elv_iosched_store,
392};
393
394static struct queue_sysfs_entry queue_hw_sector_size_entry = {
395 .attr = {.name = "hw_sector_size", .mode = S_IRUGO },
396 .show = queue_logical_block_size_show,
397};
398
399static struct queue_sysfs_entry queue_logical_block_size_entry = {
400 .attr = {.name = "logical_block_size", .mode = S_IRUGO },
401 .show = queue_logical_block_size_show,
402};
403
404static struct queue_sysfs_entry queue_physical_block_size_entry = {
405 .attr = {.name = "physical_block_size", .mode = S_IRUGO },
406 .show = queue_physical_block_size_show,
407};
408
409static struct queue_sysfs_entry queue_io_min_entry = {
410 .attr = {.name = "minimum_io_size", .mode = S_IRUGO },
411 .show = queue_io_min_show,
412};
413
414static struct queue_sysfs_entry queue_io_opt_entry = {
415 .attr = {.name = "optimal_io_size", .mode = S_IRUGO },
416 .show = queue_io_opt_show,
417};
418
419static struct queue_sysfs_entry queue_discard_granularity_entry = {
420 .attr = {.name = "discard_granularity", .mode = S_IRUGO },
421 .show = queue_discard_granularity_show,
422};
423
424static struct queue_sysfs_entry queue_discard_max_hw_entry = {
425 .attr = {.name = "discard_max_hw_bytes", .mode = S_IRUGO },
426 .show = queue_discard_max_hw_show,
427};
428
429static struct queue_sysfs_entry queue_discard_max_entry = {
430 .attr = {.name = "discard_max_bytes", .mode = S_IRUGO | S_IWUSR },
431 .show = queue_discard_max_show,
432 .store = queue_discard_max_store,
433};
434
435static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
436 .attr = {.name = "discard_zeroes_data", .mode = S_IRUGO },
437 .show = queue_discard_zeroes_data_show,
438};
439
440static struct queue_sysfs_entry queue_write_same_max_entry = {
441 .attr = {.name = "write_same_max_bytes", .mode = S_IRUGO },
442 .show = queue_write_same_max_show,
443};
444
445static struct queue_sysfs_entry queue_nonrot_entry = {
446 .attr = {.name = "rotational", .mode = S_IRUGO | S_IWUSR },
447 .show = queue_show_nonrot,
448 .store = queue_store_nonrot,
449};
450
451static struct queue_sysfs_entry queue_nomerges_entry = {
452 .attr = {.name = "nomerges", .mode = S_IRUGO | S_IWUSR },
453 .show = queue_nomerges_show,
454 .store = queue_nomerges_store,
455};
456
457static struct queue_sysfs_entry queue_rq_affinity_entry = {
458 .attr = {.name = "rq_affinity", .mode = S_IRUGO | S_IWUSR },
459 .show = queue_rq_affinity_show,
460 .store = queue_rq_affinity_store,
461};
462
463static struct queue_sysfs_entry queue_iostats_entry = {
464 .attr = {.name = "iostats", .mode = S_IRUGO | S_IWUSR },
465 .show = queue_show_iostats,
466 .store = queue_store_iostats,
467};
468
469static struct queue_sysfs_entry queue_random_entry = {
470 .attr = {.name = "add_random", .mode = S_IRUGO | S_IWUSR },
471 .show = queue_show_random,
472 .store = queue_store_random,
473};
474
475static struct queue_sysfs_entry queue_poll_entry = {
476 .attr = {.name = "io_poll", .mode = S_IRUGO | S_IWUSR },
477 .show = queue_poll_show,
478 .store = queue_poll_store,
479};
480
481static struct attribute *default_attrs[] = {
482 &queue_requests_entry.attr,
483 &queue_ra_entry.attr,
484 &queue_max_hw_sectors_entry.attr,
485 &queue_max_sectors_entry.attr,
486 &queue_max_segments_entry.attr,
487 &queue_max_integrity_segments_entry.attr,
488 &queue_max_segment_size_entry.attr,
489 &queue_iosched_entry.attr,
490 &queue_hw_sector_size_entry.attr,
491 &queue_logical_block_size_entry.attr,
492 &queue_physical_block_size_entry.attr,
493 &queue_io_min_entry.attr,
494 &queue_io_opt_entry.attr,
495 &queue_discard_granularity_entry.attr,
496 &queue_discard_max_entry.attr,
497 &queue_discard_max_hw_entry.attr,
498 &queue_discard_zeroes_data_entry.attr,
499 &queue_write_same_max_entry.attr,
500 &queue_nonrot_entry.attr,
501 &queue_nomerges_entry.attr,
502 &queue_rq_affinity_entry.attr,
503 &queue_iostats_entry.attr,
504 &queue_random_entry.attr,
505 &queue_poll_entry.attr,
506 NULL,
507};
508
509#define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
510
511static ssize_t
512queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
513{
514 struct queue_sysfs_entry *entry = to_queue(attr);
515 struct request_queue *q =
516 container_of(kobj, struct request_queue, kobj);
517 ssize_t res;
518
519 if (!entry->show)
520 return -EIO;
521 mutex_lock(&q->sysfs_lock);
522 if (blk_queue_dying(q)) {
523 mutex_unlock(&q->sysfs_lock);
524 return -ENOENT;
525 }
526 res = entry->show(q, page);
527 mutex_unlock(&q->sysfs_lock);
528 return res;
529}
530
531static ssize_t
532queue_attr_store(struct kobject *kobj, struct attribute *attr,
533 const char *page, size_t length)
534{
535 struct queue_sysfs_entry *entry = to_queue(attr);
536 struct request_queue *q;
537 ssize_t res;
538
539 if (!entry->store)
540 return -EIO;
541
542 q = container_of(kobj, struct request_queue, kobj);
543 mutex_lock(&q->sysfs_lock);
544 if (blk_queue_dying(q)) {
545 mutex_unlock(&q->sysfs_lock);
546 return -ENOENT;
547 }
548 res = entry->store(q, page, length);
549 mutex_unlock(&q->sysfs_lock);
550 return res;
551}
552
553static void blk_free_queue_rcu(struct rcu_head *rcu_head)
554{
555 struct request_queue *q = container_of(rcu_head, struct request_queue,
556 rcu_head);
557 kmem_cache_free(blk_requestq_cachep, q);
558}
559
560/**
561 * blk_release_queue: - release a &struct request_queue when it is no longer needed
562 * @kobj: the kobj belonging to the request queue to be released
563 *
564 * Description:
565 * blk_release_queue is the pair to blk_init_queue() or
566 * blk_queue_make_request(). It should be called when a request queue is
567 * being released; typically when a block device is being de-registered.
568 * Currently, its primary task it to free all the &struct request
569 * structures that were allocated to the queue and the queue itself.
570 *
571 * Note:
572 * The low level driver must have finished any outstanding requests first
573 * via blk_cleanup_queue().
574 **/
575static void blk_release_queue(struct kobject *kobj)
576{
577 struct request_queue *q =
578 container_of(kobj, struct request_queue, kobj);
579
580 bdi_exit(&q->backing_dev_info);
581 blkcg_exit_queue(q);
582
583 if (q->elevator) {
584 spin_lock_irq(q->queue_lock);
585 ioc_clear_queue(q);
586 spin_unlock_irq(q->queue_lock);
587 elevator_exit(q->elevator);
588 }
589
590 blk_exit_rl(&q->root_rl);
591
592 if (q->queue_tags)
593 __blk_queue_free_tags(q);
594
595 if (!q->mq_ops)
596 blk_free_flush_queue(q->fq);
597 else
598 blk_mq_release(q);
599
600 blk_trace_shutdown(q);
601
602 if (q->bio_split)
603 bioset_free(q->bio_split);
604
605 ida_simple_remove(&blk_queue_ida, q->id);
606 call_rcu(&q->rcu_head, blk_free_queue_rcu);
607}
608
609static const struct sysfs_ops queue_sysfs_ops = {
610 .show = queue_attr_show,
611 .store = queue_attr_store,
612};
613
614struct kobj_type blk_queue_ktype = {
615 .sysfs_ops = &queue_sysfs_ops,
616 .default_attrs = default_attrs,
617 .release = blk_release_queue,
618};
619
620int blk_register_queue(struct gendisk *disk)
621{
622 int ret;
623 struct device *dev = disk_to_dev(disk);
624 struct request_queue *q = disk->queue;
625
626 if (WARN_ON(!q))
627 return -ENXIO;
628
629 /*
630 * SCSI probing may synchronously create and destroy a lot of
631 * request_queues for non-existent devices. Shutting down a fully
632 * functional queue takes measureable wallclock time as RCU grace
633 * periods are involved. To avoid excessive latency in these
634 * cases, a request_queue starts out in a degraded mode which is
635 * faster to shut down and is made fully functional here as
636 * request_queues for non-existent devices never get registered.
637 */
638 if (!blk_queue_init_done(q)) {
639 queue_flag_set_unlocked(QUEUE_FLAG_INIT_DONE, q);
640 percpu_ref_switch_to_percpu(&q->q_usage_counter);
641 blk_queue_bypass_end(q);
642 }
643
644 ret = blk_trace_init_sysfs(dev);
645 if (ret)
646 return ret;
647
648 ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
649 if (ret < 0) {
650 blk_trace_remove_sysfs(dev);
651 return ret;
652 }
653
654 kobject_uevent(&q->kobj, KOBJ_ADD);
655
656 if (q->mq_ops)
657 blk_mq_register_disk(disk);
658
659 if (!q->request_fn)
660 return 0;
661
662 ret = elv_register_queue(q);
663 if (ret) {
664 kobject_uevent(&q->kobj, KOBJ_REMOVE);
665 kobject_del(&q->kobj);
666 blk_trace_remove_sysfs(dev);
667 kobject_put(&dev->kobj);
668 return ret;
669 }
670
671 return 0;
672}
673
674void blk_unregister_queue(struct gendisk *disk)
675{
676 struct request_queue *q = disk->queue;
677
678 if (WARN_ON(!q))
679 return;
680
681 if (q->mq_ops)
682 blk_mq_unregister_disk(disk);
683
684 if (q->request_fn)
685 elv_unregister_queue(q);
686
687 kobject_uevent(&q->kobj, KOBJ_REMOVE);
688 kobject_del(&q->kobj);
689 blk_trace_remove_sysfs(disk_to_dev(disk));
690 kobject_put(&disk_to_dev(disk)->kobj);
691}