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>
14 #include <linux/debugfs.h>
18 #include "blk-mq-debugfs.h"
21 struct queue_sysfs_entry {
22 struct attribute attr;
23 ssize_t (*show)(struct request_queue *, char *);
24 ssize_t (*store)(struct request_queue *, const char *, size_t);
28 queue_var_show(unsigned long var, char *page)
30 return sprintf(page, "%lu\n", var);
34 queue_var_store(unsigned long *var, const char *page, size_t count)
39 err = kstrtoul(page, 10, &v);
40 if (err || v > UINT_MAX)
48 static ssize_t queue_var_store64(s64 *var, const char *page)
53 err = kstrtos64(page, 10, &v);
61 static ssize_t queue_requests_show(struct request_queue *q, char *page)
63 return queue_var_show(q->nr_requests, (page));
67 queue_requests_store(struct request_queue *q, const char *page, size_t count)
75 ret = queue_var_store(&nr, page, count);
79 if (nr < BLKDEV_MIN_RQ)
82 err = blk_mq_update_nr_requests(q, nr);
89 static ssize_t queue_ra_show(struct request_queue *q, char *page)
91 unsigned long ra_kb = q->backing_dev_info->ra_pages <<
94 return queue_var_show(ra_kb, (page));
98 queue_ra_store(struct request_queue *q, const char *page, size_t count)
101 ssize_t ret = queue_var_store(&ra_kb, page, count);
106 q->backing_dev_info->ra_pages = ra_kb >> (PAGE_SHIFT - 10);
111 static ssize_t queue_max_sectors_show(struct request_queue *q, char *page)
113 int max_sectors_kb = queue_max_sectors(q) >> 1;
115 return queue_var_show(max_sectors_kb, (page));
118 static ssize_t queue_max_segments_show(struct request_queue *q, char *page)
120 return queue_var_show(queue_max_segments(q), (page));
123 static ssize_t queue_max_discard_segments_show(struct request_queue *q,
126 return queue_var_show(queue_max_discard_segments(q), (page));
129 static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page)
131 return queue_var_show(q->limits.max_integrity_segments, (page));
134 static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page)
136 return queue_var_show(queue_max_segment_size(q), (page));
139 static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page)
141 return queue_var_show(queue_logical_block_size(q), page);
144 static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page)
146 return queue_var_show(queue_physical_block_size(q), page);
149 static ssize_t queue_chunk_sectors_show(struct request_queue *q, char *page)
151 return queue_var_show(q->limits.chunk_sectors, page);
154 static ssize_t queue_io_min_show(struct request_queue *q, char *page)
156 return queue_var_show(queue_io_min(q), page);
159 static ssize_t queue_io_opt_show(struct request_queue *q, char *page)
161 return queue_var_show(queue_io_opt(q), page);
164 static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page)
166 return queue_var_show(q->limits.discard_granularity, page);
169 static ssize_t queue_discard_max_hw_show(struct request_queue *q, char *page)
172 return sprintf(page, "%llu\n",
173 (unsigned long long)q->limits.max_hw_discard_sectors << 9);
176 static ssize_t queue_discard_max_show(struct request_queue *q, char *page)
178 return sprintf(page, "%llu\n",
179 (unsigned long long)q->limits.max_discard_sectors << 9);
182 static ssize_t queue_discard_max_store(struct request_queue *q,
183 const char *page, size_t count)
185 unsigned long max_discard;
186 ssize_t ret = queue_var_store(&max_discard, page, count);
191 if (max_discard & (q->limits.discard_granularity - 1))
195 if (max_discard > UINT_MAX)
198 if (max_discard > q->limits.max_hw_discard_sectors)
199 max_discard = q->limits.max_hw_discard_sectors;
201 q->limits.max_discard_sectors = max_discard;
205 static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page)
207 return queue_var_show(0, page);
210 static ssize_t queue_write_same_max_show(struct request_queue *q, char *page)
212 return sprintf(page, "%llu\n",
213 (unsigned long long)q->limits.max_write_same_sectors << 9);
216 static ssize_t queue_write_zeroes_max_show(struct request_queue *q, char *page)
218 return sprintf(page, "%llu\n",
219 (unsigned long long)q->limits.max_write_zeroes_sectors << 9);
222 static ssize_t queue_zone_write_granularity_show(struct request_queue *q,
225 return queue_var_show(queue_zone_write_granularity(q), page);
228 static ssize_t queue_zone_append_max_show(struct request_queue *q, char *page)
230 unsigned long long max_sectors = q->limits.max_zone_append_sectors;
232 return sprintf(page, "%llu\n", max_sectors << SECTOR_SHIFT);
236 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
238 unsigned long max_sectors_kb,
239 max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
240 page_kb = 1 << (PAGE_SHIFT - 10);
241 ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
246 max_hw_sectors_kb = min_not_zero(max_hw_sectors_kb, (unsigned long)
247 q->limits.max_dev_sectors >> 1);
249 if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb)
252 spin_lock_irq(&q->queue_lock);
253 q->limits.max_sectors = max_sectors_kb << 1;
254 q->backing_dev_info->io_pages = max_sectors_kb >> (PAGE_SHIFT - 10);
255 spin_unlock_irq(&q->queue_lock);
260 static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page)
262 int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
264 return queue_var_show(max_hw_sectors_kb, (page));
267 #define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \
269 queue_##name##_show(struct request_queue *q, char *page) \
272 bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \
273 return queue_var_show(neg ? !bit : bit, page); \
276 queue_##name##_store(struct request_queue *q, const char *page, size_t count) \
280 ret = queue_var_store(&val, page, count); \
287 blk_queue_flag_set(QUEUE_FLAG_##flag, q); \
289 blk_queue_flag_clear(QUEUE_FLAG_##flag, q); \
293 QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
294 QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
295 QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
296 QUEUE_SYSFS_BIT_FNS(stable_writes, STABLE_WRITES, 0);
297 #undef QUEUE_SYSFS_BIT_FNS
299 static ssize_t queue_zoned_show(struct request_queue *q, char *page)
301 switch (blk_queue_zoned_model(q)) {
303 return sprintf(page, "host-aware\n");
305 return sprintf(page, "host-managed\n");
307 return sprintf(page, "none\n");
311 static ssize_t queue_nr_zones_show(struct request_queue *q, char *page)
313 return queue_var_show(blk_queue_nr_zones(q), page);
316 static ssize_t queue_max_open_zones_show(struct request_queue *q, char *page)
318 return queue_var_show(queue_max_open_zones(q), page);
321 static ssize_t queue_max_active_zones_show(struct request_queue *q, char *page)
323 return queue_var_show(queue_max_active_zones(q), page);
326 static ssize_t queue_nomerges_show(struct request_queue *q, char *page)
328 return queue_var_show((blk_queue_nomerges(q) << 1) |
329 blk_queue_noxmerges(q), page);
332 static ssize_t queue_nomerges_store(struct request_queue *q, const char *page,
336 ssize_t ret = queue_var_store(&nm, page, count);
341 blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
342 blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
344 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, q);
346 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
351 static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page)
353 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
354 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags);
356 return queue_var_show(set << force, page);
360 queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
362 ssize_t ret = -EINVAL;
366 ret = queue_var_store(&val, page, count);
371 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
372 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
373 } else if (val == 1) {
374 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
375 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
376 } else if (val == 0) {
377 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
378 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
384 static ssize_t queue_poll_delay_show(struct request_queue *q, char *page)
388 if (q->poll_nsec == BLK_MQ_POLL_CLASSIC)
389 val = BLK_MQ_POLL_CLASSIC;
391 val = q->poll_nsec / 1000;
393 return sprintf(page, "%d\n", val);
396 static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page,
401 if (!q->mq_ops || !q->mq_ops->poll)
404 err = kstrtoint(page, 10, &val);
408 if (val == BLK_MQ_POLL_CLASSIC)
409 q->poll_nsec = BLK_MQ_POLL_CLASSIC;
411 q->poll_nsec = val * 1000;
418 static ssize_t queue_poll_show(struct request_queue *q, char *page)
420 return queue_var_show(test_bit(QUEUE_FLAG_POLL, &q->queue_flags), page);
423 static ssize_t queue_poll_store(struct request_queue *q, const char *page,
426 unsigned long poll_on;
429 if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL ||
430 !q->tag_set->map[HCTX_TYPE_POLL].nr_queues)
433 ret = queue_var_store(&poll_on, page, count);
438 blk_queue_flag_set(QUEUE_FLAG_POLL, q);
440 blk_queue_flag_clear(QUEUE_FLAG_POLL, q);
445 static ssize_t queue_io_timeout_show(struct request_queue *q, char *page)
447 return sprintf(page, "%u\n", jiffies_to_msecs(q->rq_timeout));
450 static ssize_t queue_io_timeout_store(struct request_queue *q, const char *page,
456 err = kstrtou32(page, 10, &val);
460 blk_queue_rq_timeout(q, msecs_to_jiffies(val));
465 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page)
470 return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000));
473 static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page,
480 ret = queue_var_store64(&val, page);
486 rqos = wbt_rq_qos(q);
494 val = wbt_default_latency_nsec(q);
498 if (wbt_get_min_lat(q) == val)
502 * Ensure that the queue is idled, in case the latency update
503 * ends up either enabling or disabling wbt completely. We can't
504 * have IO inflight if that happens.
506 blk_mq_freeze_queue(q);
507 blk_mq_quiesce_queue(q);
509 wbt_set_min_lat(q, val);
511 blk_mq_unquiesce_queue(q);
512 blk_mq_unfreeze_queue(q);
517 static ssize_t queue_wc_show(struct request_queue *q, char *page)
519 if (test_bit(QUEUE_FLAG_WC, &q->queue_flags))
520 return sprintf(page, "write back\n");
522 return sprintf(page, "write through\n");
525 static ssize_t queue_wc_store(struct request_queue *q, const char *page,
530 if (!strncmp(page, "write back", 10))
532 else if (!strncmp(page, "write through", 13) ||
533 !strncmp(page, "none", 4))
540 blk_queue_flag_set(QUEUE_FLAG_WC, q);
542 blk_queue_flag_clear(QUEUE_FLAG_WC, q);
547 static ssize_t queue_fua_show(struct request_queue *q, char *page)
549 return sprintf(page, "%u\n", test_bit(QUEUE_FLAG_FUA, &q->queue_flags));
552 static ssize_t queue_dax_show(struct request_queue *q, char *page)
554 return queue_var_show(blk_queue_dax(q), page);
557 #define QUEUE_RO_ENTRY(_prefix, _name) \
558 static struct queue_sysfs_entry _prefix##_entry = { \
559 .attr = { .name = _name, .mode = 0444 }, \
560 .show = _prefix##_show, \
563 #define QUEUE_RW_ENTRY(_prefix, _name) \
564 static struct queue_sysfs_entry _prefix##_entry = { \
565 .attr = { .name = _name, .mode = 0644 }, \
566 .show = _prefix##_show, \
567 .store = _prefix##_store, \
570 QUEUE_RW_ENTRY(queue_requests, "nr_requests");
571 QUEUE_RW_ENTRY(queue_ra, "read_ahead_kb");
572 QUEUE_RW_ENTRY(queue_max_sectors, "max_sectors_kb");
573 QUEUE_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb");
574 QUEUE_RO_ENTRY(queue_max_segments, "max_segments");
575 QUEUE_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments");
576 QUEUE_RO_ENTRY(queue_max_segment_size, "max_segment_size");
577 QUEUE_RW_ENTRY(elv_iosched, "scheduler");
579 QUEUE_RO_ENTRY(queue_logical_block_size, "logical_block_size");
580 QUEUE_RO_ENTRY(queue_physical_block_size, "physical_block_size");
581 QUEUE_RO_ENTRY(queue_chunk_sectors, "chunk_sectors");
582 QUEUE_RO_ENTRY(queue_io_min, "minimum_io_size");
583 QUEUE_RO_ENTRY(queue_io_opt, "optimal_io_size");
585 QUEUE_RO_ENTRY(queue_max_discard_segments, "max_discard_segments");
586 QUEUE_RO_ENTRY(queue_discard_granularity, "discard_granularity");
587 QUEUE_RO_ENTRY(queue_discard_max_hw, "discard_max_hw_bytes");
588 QUEUE_RW_ENTRY(queue_discard_max, "discard_max_bytes");
589 QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data");
591 QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes");
592 QUEUE_RO_ENTRY(queue_write_zeroes_max, "write_zeroes_max_bytes");
593 QUEUE_RO_ENTRY(queue_zone_append_max, "zone_append_max_bytes");
594 QUEUE_RO_ENTRY(queue_zone_write_granularity, "zone_write_granularity");
596 QUEUE_RO_ENTRY(queue_zoned, "zoned");
597 QUEUE_RO_ENTRY(queue_nr_zones, "nr_zones");
598 QUEUE_RO_ENTRY(queue_max_open_zones, "max_open_zones");
599 QUEUE_RO_ENTRY(queue_max_active_zones, "max_active_zones");
601 QUEUE_RW_ENTRY(queue_nomerges, "nomerges");
602 QUEUE_RW_ENTRY(queue_rq_affinity, "rq_affinity");
603 QUEUE_RW_ENTRY(queue_poll, "io_poll");
604 QUEUE_RW_ENTRY(queue_poll_delay, "io_poll_delay");
605 QUEUE_RW_ENTRY(queue_wc, "write_cache");
606 QUEUE_RO_ENTRY(queue_fua, "fua");
607 QUEUE_RO_ENTRY(queue_dax, "dax");
608 QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout");
609 QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec");
611 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
612 QUEUE_RW_ENTRY(blk_throtl_sample_time, "throttle_sample_time");
615 /* legacy alias for logical_block_size: */
616 static struct queue_sysfs_entry queue_hw_sector_size_entry = {
617 .attr = {.name = "hw_sector_size", .mode = 0444 },
618 .show = queue_logical_block_size_show,
621 QUEUE_RW_ENTRY(queue_nonrot, "rotational");
622 QUEUE_RW_ENTRY(queue_iostats, "iostats");
623 QUEUE_RW_ENTRY(queue_random, "add_random");
624 QUEUE_RW_ENTRY(queue_stable_writes, "stable_writes");
626 static struct attribute *queue_attrs[] = {
627 &queue_requests_entry.attr,
628 &queue_ra_entry.attr,
629 &queue_max_hw_sectors_entry.attr,
630 &queue_max_sectors_entry.attr,
631 &queue_max_segments_entry.attr,
632 &queue_max_discard_segments_entry.attr,
633 &queue_max_integrity_segments_entry.attr,
634 &queue_max_segment_size_entry.attr,
635 &elv_iosched_entry.attr,
636 &queue_hw_sector_size_entry.attr,
637 &queue_logical_block_size_entry.attr,
638 &queue_physical_block_size_entry.attr,
639 &queue_chunk_sectors_entry.attr,
640 &queue_io_min_entry.attr,
641 &queue_io_opt_entry.attr,
642 &queue_discard_granularity_entry.attr,
643 &queue_discard_max_entry.attr,
644 &queue_discard_max_hw_entry.attr,
645 &queue_discard_zeroes_data_entry.attr,
646 &queue_write_same_max_entry.attr,
647 &queue_write_zeroes_max_entry.attr,
648 &queue_zone_append_max_entry.attr,
649 &queue_zone_write_granularity_entry.attr,
650 &queue_nonrot_entry.attr,
651 &queue_zoned_entry.attr,
652 &queue_nr_zones_entry.attr,
653 &queue_max_open_zones_entry.attr,
654 &queue_max_active_zones_entry.attr,
655 &queue_nomerges_entry.attr,
656 &queue_rq_affinity_entry.attr,
657 &queue_iostats_entry.attr,
658 &queue_stable_writes_entry.attr,
659 &queue_random_entry.attr,
660 &queue_poll_entry.attr,
661 &queue_wc_entry.attr,
662 &queue_fua_entry.attr,
663 &queue_dax_entry.attr,
664 &queue_wb_lat_entry.attr,
665 &queue_poll_delay_entry.attr,
666 &queue_io_timeout_entry.attr,
667 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
668 &blk_throtl_sample_time_entry.attr,
673 static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr,
676 struct request_queue *q =
677 container_of(kobj, struct request_queue, kobj);
679 if (attr == &queue_io_timeout_entry.attr &&
680 (!q->mq_ops || !q->mq_ops->timeout))
683 if ((attr == &queue_max_open_zones_entry.attr ||
684 attr == &queue_max_active_zones_entry.attr) &&
685 !blk_queue_is_zoned(q))
691 static struct attribute_group queue_attr_group = {
692 .attrs = queue_attrs,
693 .is_visible = queue_attr_visible,
697 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
700 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
702 struct queue_sysfs_entry *entry = to_queue(attr);
703 struct request_queue *q =
704 container_of(kobj, struct request_queue, kobj);
709 mutex_lock(&q->sysfs_lock);
710 res = entry->show(q, page);
711 mutex_unlock(&q->sysfs_lock);
716 queue_attr_store(struct kobject *kobj, struct attribute *attr,
717 const char *page, size_t length)
719 struct queue_sysfs_entry *entry = to_queue(attr);
720 struct request_queue *q;
726 q = container_of(kobj, struct request_queue, kobj);
727 mutex_lock(&q->sysfs_lock);
728 res = entry->store(q, page, length);
729 mutex_unlock(&q->sysfs_lock);
733 static void blk_free_queue_rcu(struct rcu_head *rcu_head)
735 struct request_queue *q = container_of(rcu_head, struct request_queue,
737 kmem_cache_free(blk_requestq_cachep, q);
740 /* Unconfigure the I/O scheduler and dissociate from the cgroup controller. */
741 static void blk_exit_queue(struct request_queue *q)
744 * Since the I/O scheduler exit code may access cgroup information,
745 * perform I/O scheduler exit before disassociating from the block
750 __elevator_exit(q, q->elevator);
754 * Remove all references to @q from the block cgroup controller before
755 * restoring @q->queue_lock to avoid that restoring this pointer causes
756 * e.g. blkcg_print_blkgs() to crash.
761 * Since the cgroup code may dereference the @q->backing_dev_info
762 * pointer, only decrease its reference count after having removed the
763 * association with the block cgroup controller.
765 bdi_put(q->backing_dev_info);
769 * blk_release_queue - releases all allocated resources of the request_queue
770 * @kobj: pointer to a kobject, whose container is a request_queue
772 * This function releases all allocated resources of the request queue.
774 * The struct request_queue refcount is incremented with blk_get_queue() and
775 * decremented with blk_put_queue(). Once the refcount reaches 0 this function
778 * For drivers that have a request_queue on a gendisk and added with
779 * __device_add_disk() the refcount to request_queue will reach 0 with
780 * the last put_disk() called by the driver. For drivers which don't use
781 * __device_add_disk() this happens with blk_cleanup_queue().
783 * Drivers exist which depend on the release of the request_queue to be
784 * synchronous, it should not be deferred.
788 static void blk_release_queue(struct kobject *kobj)
790 struct request_queue *q =
791 container_of(kobj, struct request_queue, kobj);
795 if (test_bit(QUEUE_FLAG_POLL_STATS, &q->queue_flags))
796 blk_stat_remove_callback(q, q->poll_cb);
797 blk_stat_free_callback(q->poll_cb);
799 blk_free_queue_stats(q->stats);
801 if (queue_is_mq(q)) {
802 struct blk_mq_hw_ctx *hctx;
805 cancel_delayed_work_sync(&q->requeue_work);
807 queue_for_each_hw_ctx(q, hctx, i)
808 cancel_delayed_work_sync(&hctx->run_work);
813 blk_queue_free_zone_bitmaps(q);
818 blk_trace_shutdown(q);
819 mutex_lock(&q->debugfs_mutex);
820 debugfs_remove_recursive(q->debugfs_dir);
821 mutex_unlock(&q->debugfs_mutex);
824 blk_mq_debugfs_unregister(q);
826 bioset_exit(&q->bio_split);
828 ida_simple_remove(&blk_queue_ida, q->id);
829 call_rcu(&q->rcu_head, blk_free_queue_rcu);
832 static const struct sysfs_ops queue_sysfs_ops = {
833 .show = queue_attr_show,
834 .store = queue_attr_store,
837 struct kobj_type blk_queue_ktype = {
838 .sysfs_ops = &queue_sysfs_ops,
839 .release = blk_release_queue,
843 * blk_register_queue - register a block layer queue with sysfs
844 * @disk: Disk of which the request queue should be registered with sysfs.
846 int blk_register_queue(struct gendisk *disk)
849 struct device *dev = disk_to_dev(disk);
850 struct request_queue *q = disk->queue;
855 WARN_ONCE(blk_queue_registered(q),
856 "%s is registering an already registered queue\n",
857 kobject_name(&dev->kobj));
860 * SCSI probing may synchronously create and destroy a lot of
861 * request_queues for non-existent devices. Shutting down a fully
862 * functional queue takes measureable wallclock time as RCU grace
863 * periods are involved. To avoid excessive latency in these
864 * cases, a request_queue starts out in a degraded mode which is
865 * faster to shut down and is made fully functional here as
866 * request_queues for non-existent devices never get registered.
868 if (!blk_queue_init_done(q)) {
869 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q);
870 percpu_ref_switch_to_percpu(&q->q_usage_counter);
873 blk_queue_update_readahead(q);
875 ret = blk_trace_init_sysfs(dev);
879 mutex_lock(&q->sysfs_dir_lock);
881 ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
883 blk_trace_remove_sysfs(dev);
887 ret = sysfs_create_group(&q->kobj, &queue_attr_group);
889 blk_trace_remove_sysfs(dev);
890 kobject_del(&q->kobj);
891 kobject_put(&dev->kobj);
895 mutex_lock(&q->debugfs_mutex);
896 q->debugfs_dir = debugfs_create_dir(kobject_name(q->kobj.parent),
898 mutex_unlock(&q->debugfs_mutex);
900 if (queue_is_mq(q)) {
901 __blk_mq_register_dev(dev, q);
902 blk_mq_debugfs_register(q);
905 mutex_lock(&q->sysfs_lock);
907 ret = elv_register_queue(q, false);
909 mutex_unlock(&q->sysfs_lock);
910 mutex_unlock(&q->sysfs_dir_lock);
911 kobject_del(&q->kobj);
912 blk_trace_remove_sysfs(dev);
913 kobject_put(&dev->kobj);
918 blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q);
919 wbt_enable_default(q);
920 blk_throtl_register_queue(q);
922 /* Now everything is ready and send out KOBJ_ADD uevent */
923 kobject_uevent(&q->kobj, KOBJ_ADD);
925 kobject_uevent(&q->elevator->kobj, KOBJ_ADD);
926 mutex_unlock(&q->sysfs_lock);
930 mutex_unlock(&q->sysfs_dir_lock);
933 EXPORT_SYMBOL_GPL(blk_register_queue);
936 * blk_unregister_queue - counterpart of blk_register_queue()
937 * @disk: Disk of which the request queue should be unregistered from sysfs.
939 * Note: the caller is responsible for guaranteeing that this function is called
940 * after blk_register_queue() has finished.
942 void blk_unregister_queue(struct gendisk *disk)
944 struct request_queue *q = disk->queue;
949 /* Return early if disk->queue was never registered. */
950 if (!blk_queue_registered(q))
954 * Since sysfs_remove_dir() prevents adding new directory entries
955 * before removal of existing entries starts, protect against
956 * concurrent elv_iosched_store() calls.
958 mutex_lock(&q->sysfs_lock);
959 blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q);
960 mutex_unlock(&q->sysfs_lock);
962 mutex_lock(&q->sysfs_dir_lock);
964 * Remove the sysfs attributes before unregistering the queue data
965 * structures that can be modified through sysfs.
968 blk_mq_unregister_dev(disk_to_dev(disk), q);
970 kobject_uevent(&q->kobj, KOBJ_REMOVE);
971 kobject_del(&q->kobj);
972 blk_trace_remove_sysfs(disk_to_dev(disk));
974 mutex_lock(&q->sysfs_lock);
976 elv_unregister_queue(q);
977 mutex_unlock(&q->sysfs_lock);
978 mutex_unlock(&q->sysfs_dir_lock);
980 kobject_put(&disk_to_dev(disk)->kobj);