1 // SPDX-License-Identifier: GPL-2.0
3 * Functions related to sysfs handling
5 #include <linux/kernel.h>
6 #include <linux/slab.h>
7 #include <linux/module.h>
9 #include <linux/blkdev.h>
10 #include <linux/backing-dev.h>
11 #include <linux/blktrace_api.h>
12 #include <linux/blk-mq.h>
13 #include <linux/blk-cgroup.h>
17 #include "blk-mq-debugfs.h"
20 struct queue_sysfs_entry {
21 struct attribute attr;
22 ssize_t (*show)(struct request_queue *, char *);
23 ssize_t (*store)(struct request_queue *, const char *, size_t);
27 queue_var_show(unsigned long var, char *page)
29 return sprintf(page, "%lu\n", var);
33 queue_var_store(unsigned long *var, const char *page, size_t count)
38 err = kstrtoul(page, 10, &v);
39 if (err || v > UINT_MAX)
47 static ssize_t queue_var_store64(s64 *var, const char *page)
52 err = kstrtos64(page, 10, &v);
60 static ssize_t queue_requests_show(struct request_queue *q, char *page)
62 return queue_var_show(q->nr_requests, (page));
66 queue_requests_store(struct request_queue *q, const char *page, size_t count)
71 if (!q->request_fn && !q->mq_ops)
74 ret = queue_var_store(&nr, page, count);
78 if (nr < BLKDEV_MIN_RQ)
82 err = blk_update_nr_requests(q, nr);
84 err = blk_mq_update_nr_requests(q, nr);
92 static ssize_t queue_ra_show(struct request_queue *q, char *page)
94 unsigned long ra_kb = q->backing_dev_info->ra_pages <<
97 return queue_var_show(ra_kb, (page));
101 queue_ra_store(struct request_queue *q, const char *page, size_t count)
104 ssize_t ret = queue_var_store(&ra_kb, page, count);
109 q->backing_dev_info->ra_pages = ra_kb >> (PAGE_SHIFT - 10);
114 static ssize_t queue_max_sectors_show(struct request_queue *q, char *page)
116 int max_sectors_kb = queue_max_sectors(q) >> 1;
118 return queue_var_show(max_sectors_kb, (page));
121 static ssize_t queue_max_segments_show(struct request_queue *q, char *page)
123 return queue_var_show(queue_max_segments(q), (page));
126 static ssize_t queue_max_discard_segments_show(struct request_queue *q,
129 return queue_var_show(queue_max_discard_segments(q), (page));
132 static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page)
134 return queue_var_show(q->limits.max_integrity_segments, (page));
137 static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page)
139 if (blk_queue_cluster(q))
140 return queue_var_show(queue_max_segment_size(q), (page));
142 return queue_var_show(PAGE_SIZE, (page));
145 static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page)
147 return queue_var_show(queue_logical_block_size(q), page);
150 static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page)
152 return queue_var_show(queue_physical_block_size(q), page);
155 static ssize_t queue_chunk_sectors_show(struct request_queue *q, char *page)
157 return queue_var_show(q->limits.chunk_sectors, page);
160 static ssize_t queue_io_min_show(struct request_queue *q, char *page)
162 return queue_var_show(queue_io_min(q), page);
165 static ssize_t queue_io_opt_show(struct request_queue *q, char *page)
167 return queue_var_show(queue_io_opt(q), page);
170 static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page)
172 return queue_var_show(q->limits.discard_granularity, page);
175 static ssize_t queue_discard_max_hw_show(struct request_queue *q, char *page)
178 return sprintf(page, "%llu\n",
179 (unsigned long long)q->limits.max_hw_discard_sectors << 9);
182 static ssize_t queue_discard_max_show(struct request_queue *q, char *page)
184 return sprintf(page, "%llu\n",
185 (unsigned long long)q->limits.max_discard_sectors << 9);
188 static ssize_t queue_discard_max_store(struct request_queue *q,
189 const char *page, size_t count)
191 unsigned long max_discard;
192 ssize_t ret = queue_var_store(&max_discard, page, count);
197 if (max_discard & (q->limits.discard_granularity - 1))
201 if (max_discard > UINT_MAX)
204 if (max_discard > q->limits.max_hw_discard_sectors)
205 max_discard = q->limits.max_hw_discard_sectors;
207 q->limits.max_discard_sectors = max_discard;
211 static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page)
213 return queue_var_show(0, page);
216 static ssize_t queue_write_same_max_show(struct request_queue *q, char *page)
218 return sprintf(page, "%llu\n",
219 (unsigned long long)q->limits.max_write_same_sectors << 9);
222 static ssize_t queue_write_zeroes_max_show(struct request_queue *q, char *page)
224 return sprintf(page, "%llu\n",
225 (unsigned long long)q->limits.max_write_zeroes_sectors << 9);
229 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
231 unsigned long max_sectors_kb,
232 max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
233 page_kb = 1 << (PAGE_SHIFT - 10);
234 ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
239 max_hw_sectors_kb = min_not_zero(max_hw_sectors_kb, (unsigned long)
240 q->limits.max_dev_sectors >> 1);
242 if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb)
245 spin_lock_irq(q->queue_lock);
246 q->limits.max_sectors = max_sectors_kb << 1;
247 q->backing_dev_info->io_pages = max_sectors_kb >> (PAGE_SHIFT - 10);
248 spin_unlock_irq(q->queue_lock);
253 static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page)
255 int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
257 return queue_var_show(max_hw_sectors_kb, (page));
260 #define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \
262 queue_show_##name(struct request_queue *q, char *page) \
265 bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \
266 return queue_var_show(neg ? !bit : bit, page); \
269 queue_store_##name(struct request_queue *q, const char *page, size_t count) \
273 ret = queue_var_store(&val, page, count); \
279 spin_lock_irq(q->queue_lock); \
281 queue_flag_set(QUEUE_FLAG_##flag, q); \
283 queue_flag_clear(QUEUE_FLAG_##flag, q); \
284 spin_unlock_irq(q->queue_lock); \
288 QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
289 QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
290 QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
291 #undef QUEUE_SYSFS_BIT_FNS
293 static ssize_t queue_zoned_show(struct request_queue *q, char *page)
295 switch (blk_queue_zoned_model(q)) {
297 return sprintf(page, "host-aware\n");
299 return sprintf(page, "host-managed\n");
301 return sprintf(page, "none\n");
305 static ssize_t queue_nomerges_show(struct request_queue *q, char *page)
307 return queue_var_show((blk_queue_nomerges(q) << 1) |
308 blk_queue_noxmerges(q), page);
311 static ssize_t queue_nomerges_store(struct request_queue *q, const char *page,
315 ssize_t ret = queue_var_store(&nm, page, count);
320 spin_lock_irq(q->queue_lock);
321 queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
322 queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
324 queue_flag_set(QUEUE_FLAG_NOMERGES, q);
326 queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
327 spin_unlock_irq(q->queue_lock);
332 static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page)
334 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
335 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags);
337 return queue_var_show(set << force, page);
341 queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
343 ssize_t ret = -EINVAL;
347 ret = queue_var_store(&val, page, count);
351 spin_lock_irq(q->queue_lock);
353 queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
354 queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
355 } else if (val == 1) {
356 queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
357 queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
358 } else if (val == 0) {
359 queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
360 queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
362 spin_unlock_irq(q->queue_lock);
367 static ssize_t queue_poll_delay_show(struct request_queue *q, char *page)
371 if (q->poll_nsec == -1)
374 val = q->poll_nsec / 1000;
376 return sprintf(page, "%d\n", val);
379 static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page,
384 if (!q->mq_ops || !q->mq_ops->poll)
387 err = kstrtoint(page, 10, &val);
394 q->poll_nsec = val * 1000;
399 static ssize_t queue_poll_show(struct request_queue *q, char *page)
401 return queue_var_show(test_bit(QUEUE_FLAG_POLL, &q->queue_flags), page);
404 static ssize_t queue_poll_store(struct request_queue *q, const char *page,
407 unsigned long poll_on;
410 if (!q->mq_ops || !q->mq_ops->poll)
413 ret = queue_var_store(&poll_on, page, count);
417 spin_lock_irq(q->queue_lock);
419 queue_flag_set(QUEUE_FLAG_POLL, q);
421 queue_flag_clear(QUEUE_FLAG_POLL, q);
422 spin_unlock_irq(q->queue_lock);
427 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page)
432 return sprintf(page, "%llu\n", div_u64(q->rq_wb->min_lat_nsec, 1000));
435 static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page,
442 ret = queue_var_store64(&val, page);
457 rwb->min_lat_nsec = wbt_default_latency_nsec(q);
459 rwb->min_lat_nsec = val * 1000ULL;
461 if (rwb->enable_state == WBT_STATE_ON_DEFAULT)
462 rwb->enable_state = WBT_STATE_ON_MANUAL;
464 wbt_update_limits(rwb);
468 static ssize_t queue_wc_show(struct request_queue *q, char *page)
470 if (test_bit(QUEUE_FLAG_WC, &q->queue_flags))
471 return sprintf(page, "write back\n");
473 return sprintf(page, "write through\n");
476 static ssize_t queue_wc_store(struct request_queue *q, const char *page,
481 if (!strncmp(page, "write back", 10))
483 else if (!strncmp(page, "write through", 13) ||
484 !strncmp(page, "none", 4))
490 spin_lock_irq(q->queue_lock);
492 queue_flag_set(QUEUE_FLAG_WC, q);
494 queue_flag_clear(QUEUE_FLAG_WC, q);
495 spin_unlock_irq(q->queue_lock);
500 static ssize_t queue_dax_show(struct request_queue *q, char *page)
502 return queue_var_show(blk_queue_dax(q), page);
505 static struct queue_sysfs_entry queue_requests_entry = {
506 .attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR },
507 .show = queue_requests_show,
508 .store = queue_requests_store,
511 static struct queue_sysfs_entry queue_ra_entry = {
512 .attr = {.name = "read_ahead_kb", .mode = S_IRUGO | S_IWUSR },
513 .show = queue_ra_show,
514 .store = queue_ra_store,
517 static struct queue_sysfs_entry queue_max_sectors_entry = {
518 .attr = {.name = "max_sectors_kb", .mode = S_IRUGO | S_IWUSR },
519 .show = queue_max_sectors_show,
520 .store = queue_max_sectors_store,
523 static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
524 .attr = {.name = "max_hw_sectors_kb", .mode = S_IRUGO },
525 .show = queue_max_hw_sectors_show,
528 static struct queue_sysfs_entry queue_max_segments_entry = {
529 .attr = {.name = "max_segments", .mode = S_IRUGO },
530 .show = queue_max_segments_show,
533 static struct queue_sysfs_entry queue_max_discard_segments_entry = {
534 .attr = {.name = "max_discard_segments", .mode = S_IRUGO },
535 .show = queue_max_discard_segments_show,
538 static struct queue_sysfs_entry queue_max_integrity_segments_entry = {
539 .attr = {.name = "max_integrity_segments", .mode = S_IRUGO },
540 .show = queue_max_integrity_segments_show,
543 static struct queue_sysfs_entry queue_max_segment_size_entry = {
544 .attr = {.name = "max_segment_size", .mode = S_IRUGO },
545 .show = queue_max_segment_size_show,
548 static struct queue_sysfs_entry queue_iosched_entry = {
549 .attr = {.name = "scheduler", .mode = S_IRUGO | S_IWUSR },
550 .show = elv_iosched_show,
551 .store = elv_iosched_store,
554 static struct queue_sysfs_entry queue_hw_sector_size_entry = {
555 .attr = {.name = "hw_sector_size", .mode = S_IRUGO },
556 .show = queue_logical_block_size_show,
559 static struct queue_sysfs_entry queue_logical_block_size_entry = {
560 .attr = {.name = "logical_block_size", .mode = S_IRUGO },
561 .show = queue_logical_block_size_show,
564 static struct queue_sysfs_entry queue_physical_block_size_entry = {
565 .attr = {.name = "physical_block_size", .mode = S_IRUGO },
566 .show = queue_physical_block_size_show,
569 static struct queue_sysfs_entry queue_chunk_sectors_entry = {
570 .attr = {.name = "chunk_sectors", .mode = S_IRUGO },
571 .show = queue_chunk_sectors_show,
574 static struct queue_sysfs_entry queue_io_min_entry = {
575 .attr = {.name = "minimum_io_size", .mode = S_IRUGO },
576 .show = queue_io_min_show,
579 static struct queue_sysfs_entry queue_io_opt_entry = {
580 .attr = {.name = "optimal_io_size", .mode = S_IRUGO },
581 .show = queue_io_opt_show,
584 static struct queue_sysfs_entry queue_discard_granularity_entry = {
585 .attr = {.name = "discard_granularity", .mode = S_IRUGO },
586 .show = queue_discard_granularity_show,
589 static struct queue_sysfs_entry queue_discard_max_hw_entry = {
590 .attr = {.name = "discard_max_hw_bytes", .mode = S_IRUGO },
591 .show = queue_discard_max_hw_show,
594 static struct queue_sysfs_entry queue_discard_max_entry = {
595 .attr = {.name = "discard_max_bytes", .mode = S_IRUGO | S_IWUSR },
596 .show = queue_discard_max_show,
597 .store = queue_discard_max_store,
600 static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
601 .attr = {.name = "discard_zeroes_data", .mode = S_IRUGO },
602 .show = queue_discard_zeroes_data_show,
605 static struct queue_sysfs_entry queue_write_same_max_entry = {
606 .attr = {.name = "write_same_max_bytes", .mode = S_IRUGO },
607 .show = queue_write_same_max_show,
610 static struct queue_sysfs_entry queue_write_zeroes_max_entry = {
611 .attr = {.name = "write_zeroes_max_bytes", .mode = S_IRUGO },
612 .show = queue_write_zeroes_max_show,
615 static struct queue_sysfs_entry queue_nonrot_entry = {
616 .attr = {.name = "rotational", .mode = S_IRUGO | S_IWUSR },
617 .show = queue_show_nonrot,
618 .store = queue_store_nonrot,
621 static struct queue_sysfs_entry queue_zoned_entry = {
622 .attr = {.name = "zoned", .mode = S_IRUGO },
623 .show = queue_zoned_show,
626 static struct queue_sysfs_entry queue_nomerges_entry = {
627 .attr = {.name = "nomerges", .mode = S_IRUGO | S_IWUSR },
628 .show = queue_nomerges_show,
629 .store = queue_nomerges_store,
632 static struct queue_sysfs_entry queue_rq_affinity_entry = {
633 .attr = {.name = "rq_affinity", .mode = S_IRUGO | S_IWUSR },
634 .show = queue_rq_affinity_show,
635 .store = queue_rq_affinity_store,
638 static struct queue_sysfs_entry queue_iostats_entry = {
639 .attr = {.name = "iostats", .mode = S_IRUGO | S_IWUSR },
640 .show = queue_show_iostats,
641 .store = queue_store_iostats,
644 static struct queue_sysfs_entry queue_random_entry = {
645 .attr = {.name = "add_random", .mode = S_IRUGO | S_IWUSR },
646 .show = queue_show_random,
647 .store = queue_store_random,
650 static struct queue_sysfs_entry queue_poll_entry = {
651 .attr = {.name = "io_poll", .mode = S_IRUGO | S_IWUSR },
652 .show = queue_poll_show,
653 .store = queue_poll_store,
656 static struct queue_sysfs_entry queue_poll_delay_entry = {
657 .attr = {.name = "io_poll_delay", .mode = S_IRUGO | S_IWUSR },
658 .show = queue_poll_delay_show,
659 .store = queue_poll_delay_store,
662 static struct queue_sysfs_entry queue_wc_entry = {
663 .attr = {.name = "write_cache", .mode = S_IRUGO | S_IWUSR },
664 .show = queue_wc_show,
665 .store = queue_wc_store,
668 static struct queue_sysfs_entry queue_dax_entry = {
669 .attr = {.name = "dax", .mode = S_IRUGO },
670 .show = queue_dax_show,
673 static struct queue_sysfs_entry queue_wb_lat_entry = {
674 .attr = {.name = "wbt_lat_usec", .mode = S_IRUGO | S_IWUSR },
675 .show = queue_wb_lat_show,
676 .store = queue_wb_lat_store,
679 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
680 static struct queue_sysfs_entry throtl_sample_time_entry = {
681 .attr = {.name = "throttle_sample_time", .mode = S_IRUGO | S_IWUSR },
682 .show = blk_throtl_sample_time_show,
683 .store = blk_throtl_sample_time_store,
687 static struct attribute *default_attrs[] = {
688 &queue_requests_entry.attr,
689 &queue_ra_entry.attr,
690 &queue_max_hw_sectors_entry.attr,
691 &queue_max_sectors_entry.attr,
692 &queue_max_segments_entry.attr,
693 &queue_max_discard_segments_entry.attr,
694 &queue_max_integrity_segments_entry.attr,
695 &queue_max_segment_size_entry.attr,
696 &queue_iosched_entry.attr,
697 &queue_hw_sector_size_entry.attr,
698 &queue_logical_block_size_entry.attr,
699 &queue_physical_block_size_entry.attr,
700 &queue_chunk_sectors_entry.attr,
701 &queue_io_min_entry.attr,
702 &queue_io_opt_entry.attr,
703 &queue_discard_granularity_entry.attr,
704 &queue_discard_max_entry.attr,
705 &queue_discard_max_hw_entry.attr,
706 &queue_discard_zeroes_data_entry.attr,
707 &queue_write_same_max_entry.attr,
708 &queue_write_zeroes_max_entry.attr,
709 &queue_nonrot_entry.attr,
710 &queue_zoned_entry.attr,
711 &queue_nomerges_entry.attr,
712 &queue_rq_affinity_entry.attr,
713 &queue_iostats_entry.attr,
714 &queue_random_entry.attr,
715 &queue_poll_entry.attr,
716 &queue_wc_entry.attr,
717 &queue_dax_entry.attr,
718 &queue_wb_lat_entry.attr,
719 &queue_poll_delay_entry.attr,
720 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
721 &throtl_sample_time_entry.attr,
726 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
729 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
731 struct queue_sysfs_entry *entry = to_queue(attr);
732 struct request_queue *q =
733 container_of(kobj, struct request_queue, kobj);
738 mutex_lock(&q->sysfs_lock);
739 if (blk_queue_dying(q)) {
740 mutex_unlock(&q->sysfs_lock);
743 res = entry->show(q, page);
744 mutex_unlock(&q->sysfs_lock);
749 queue_attr_store(struct kobject *kobj, struct attribute *attr,
750 const char *page, size_t length)
752 struct queue_sysfs_entry *entry = to_queue(attr);
753 struct request_queue *q;
759 q = container_of(kobj, struct request_queue, kobj);
760 mutex_lock(&q->sysfs_lock);
761 if (blk_queue_dying(q)) {
762 mutex_unlock(&q->sysfs_lock);
765 res = entry->store(q, page, length);
766 mutex_unlock(&q->sysfs_lock);
770 static void blk_free_queue_rcu(struct rcu_head *rcu_head)
772 struct request_queue *q = container_of(rcu_head, struct request_queue,
774 kmem_cache_free(blk_requestq_cachep, q);
778 * __blk_release_queue - release a request queue when it is no longer needed
779 * @work: pointer to the release_work member of the request queue to be released
782 * blk_release_queue is the counterpart of blk_init_queue(). It should be
783 * called when a request queue is being released; typically when a block
784 * device is being de-registered. Its primary task it to free the queue
788 * The low level driver must have finished any outstanding requests first
789 * via blk_cleanup_queue().
791 * Although blk_release_queue() may be called with preemption disabled,
792 * __blk_release_queue() may sleep.
794 static void __blk_release_queue(struct work_struct *work)
796 struct request_queue *q = container_of(work, typeof(*q), release_work);
798 if (test_bit(QUEUE_FLAG_POLL_STATS, &q->queue_flags))
799 blk_stat_remove_callback(q, q->poll_cb);
800 blk_stat_free_callback(q->poll_cb);
801 bdi_put(q->backing_dev_info);
806 elevator_exit(q, q->elevator);
809 blk_free_queue_stats(q->stats);
811 blk_exit_rl(q, &q->root_rl);
814 __blk_queue_free_tags(q);
818 q->exit_rq_fn(q, q->fq->flush_rq);
819 blk_free_flush_queue(q->fq);
824 blk_trace_shutdown(q);
827 blk_mq_debugfs_unregister(q);
830 bioset_free(q->bio_split);
832 ida_simple_remove(&blk_queue_ida, q->id);
833 call_rcu(&q->rcu_head, blk_free_queue_rcu);
836 static void blk_release_queue(struct kobject *kobj)
838 struct request_queue *q =
839 container_of(kobj, struct request_queue, kobj);
841 INIT_WORK(&q->release_work, __blk_release_queue);
842 schedule_work(&q->release_work);
845 static const struct sysfs_ops queue_sysfs_ops = {
846 .show = queue_attr_show,
847 .store = queue_attr_store,
850 struct kobj_type blk_queue_ktype = {
851 .sysfs_ops = &queue_sysfs_ops,
852 .default_attrs = default_attrs,
853 .release = blk_release_queue,
857 * blk_register_queue - register a block layer queue with sysfs
858 * @disk: Disk of which the request queue should be registered with sysfs.
860 int blk_register_queue(struct gendisk *disk)
863 struct device *dev = disk_to_dev(disk);
864 struct request_queue *q = disk->queue;
869 WARN_ONCE(test_bit(QUEUE_FLAG_REGISTERED, &q->queue_flags),
870 "%s is registering an already registered queue\n",
871 kobject_name(&dev->kobj));
872 queue_flag_set_unlocked(QUEUE_FLAG_REGISTERED, q);
875 * SCSI probing may synchronously create and destroy a lot of
876 * request_queues for non-existent devices. Shutting down a fully
877 * functional queue takes measureable wallclock time as RCU grace
878 * periods are involved. To avoid excessive latency in these
879 * cases, a request_queue starts out in a degraded mode which is
880 * faster to shut down and is made fully functional here as
881 * request_queues for non-existent devices never get registered.
883 if (!blk_queue_init_done(q)) {
884 queue_flag_set_unlocked(QUEUE_FLAG_INIT_DONE, q);
885 percpu_ref_switch_to_percpu(&q->q_usage_counter);
886 blk_queue_bypass_end(q);
889 ret = blk_trace_init_sysfs(dev);
893 /* Prevent changes through sysfs until registration is completed. */
894 mutex_lock(&q->sysfs_lock);
896 ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
898 blk_trace_remove_sysfs(dev);
903 __blk_mq_register_dev(dev, q);
904 blk_mq_debugfs_register(q);
907 kobject_uevent(&q->kobj, KOBJ_ADD);
909 wbt_enable_default(q);
911 blk_throtl_register_queue(q);
913 if (q->request_fn || (q->mq_ops && q->elevator)) {
914 ret = elv_register_queue(q);
916 mutex_unlock(&q->sysfs_lock);
917 kobject_uevent(&q->kobj, KOBJ_REMOVE);
918 kobject_del(&q->kobj);
919 blk_trace_remove_sysfs(dev);
920 kobject_put(&dev->kobj);
926 mutex_unlock(&q->sysfs_lock);
929 EXPORT_SYMBOL_GPL(blk_register_queue);
932 * blk_unregister_queue - counterpart of blk_register_queue()
933 * @disk: Disk of which the request queue should be unregistered from sysfs.
935 * Note: the caller is responsible for guaranteeing that this function is called
936 * after blk_register_queue() has finished.
938 void blk_unregister_queue(struct gendisk *disk)
940 struct request_queue *q = disk->queue;
945 /* Return early if disk->queue was never registered. */
946 if (!test_bit(QUEUE_FLAG_REGISTERED, &q->queue_flags))
950 * Since sysfs_remove_dir() prevents adding new directory entries
951 * before removal of existing entries starts, protect against
952 * concurrent elv_iosched_store() calls.
954 mutex_lock(&q->sysfs_lock);
956 spin_lock_irq(q->queue_lock);
957 queue_flag_clear(QUEUE_FLAG_REGISTERED, q);
958 spin_unlock_irq(q->queue_lock);
961 * Remove the sysfs attributes before unregistering the queue data
962 * structures that can be modified through sysfs.
965 blk_mq_unregister_dev(disk_to_dev(disk), q);
966 mutex_unlock(&q->sysfs_lock);
968 kobject_uevent(&q->kobj, KOBJ_REMOVE);
969 kobject_del(&q->kobj);
970 blk_trace_remove_sysfs(disk_to_dev(disk));
974 mutex_lock(&q->sysfs_lock);
975 if (q->request_fn || (q->mq_ops && q->elevator))
976 elv_unregister_queue(q);
977 mutex_unlock(&q->sysfs_lock);
979 kobject_put(&disk_to_dev(disk)->kobj);