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)
74 ret = queue_var_store(&nr, page, count);
78 if (nr < BLKDEV_MIN_RQ)
81 err = blk_mq_update_nr_requests(q, nr);
88 static ssize_t queue_ra_show(struct request_queue *q, char *page)
90 unsigned long ra_kb = q->backing_dev_info->ra_pages <<
93 return queue_var_show(ra_kb, (page));
97 queue_ra_store(struct request_queue *q, const char *page, size_t count)
100 ssize_t ret = queue_var_store(&ra_kb, page, count);
105 q->backing_dev_info->ra_pages = ra_kb >> (PAGE_SHIFT - 10);
110 static ssize_t queue_max_sectors_show(struct request_queue *q, char *page)
112 int max_sectors_kb = queue_max_sectors(q) >> 1;
114 return queue_var_show(max_sectors_kb, (page));
117 static ssize_t queue_max_segments_show(struct request_queue *q, char *page)
119 return queue_var_show(queue_max_segments(q), (page));
122 static ssize_t queue_max_discard_segments_show(struct request_queue *q,
125 return queue_var_show(queue_max_discard_segments(q), (page));
128 static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page)
130 return queue_var_show(q->limits.max_integrity_segments, (page));
133 static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page)
135 return queue_var_show(queue_max_segment_size(q), (page));
138 static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page)
140 return queue_var_show(queue_logical_block_size(q), page);
143 static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page)
145 return queue_var_show(queue_physical_block_size(q), page);
148 static ssize_t queue_chunk_sectors_show(struct request_queue *q, char *page)
150 return queue_var_show(q->limits.chunk_sectors, page);
153 static ssize_t queue_io_min_show(struct request_queue *q, char *page)
155 return queue_var_show(queue_io_min(q), page);
158 static ssize_t queue_io_opt_show(struct request_queue *q, char *page)
160 return queue_var_show(queue_io_opt(q), page);
163 static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page)
165 return queue_var_show(q->limits.discard_granularity, page);
168 static ssize_t queue_discard_max_hw_show(struct request_queue *q, char *page)
171 return sprintf(page, "%llu\n",
172 (unsigned long long)q->limits.max_hw_discard_sectors << 9);
175 static ssize_t queue_discard_max_show(struct request_queue *q, char *page)
177 return sprintf(page, "%llu\n",
178 (unsigned long long)q->limits.max_discard_sectors << 9);
181 static ssize_t queue_discard_max_store(struct request_queue *q,
182 const char *page, size_t count)
184 unsigned long max_discard;
185 ssize_t ret = queue_var_store(&max_discard, page, count);
190 if (max_discard & (q->limits.discard_granularity - 1))
194 if (max_discard > UINT_MAX)
197 if (max_discard > q->limits.max_hw_discard_sectors)
198 max_discard = q->limits.max_hw_discard_sectors;
200 q->limits.max_discard_sectors = max_discard;
204 static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page)
206 return queue_var_show(0, page);
209 static ssize_t queue_write_same_max_show(struct request_queue *q, char *page)
211 return sprintf(page, "%llu\n",
212 (unsigned long long)q->limits.max_write_same_sectors << 9);
215 static ssize_t queue_write_zeroes_max_show(struct request_queue *q, char *page)
217 return sprintf(page, "%llu\n",
218 (unsigned long long)q->limits.max_write_zeroes_sectors << 9);
221 static ssize_t queue_zone_append_max_show(struct request_queue *q, char *page)
223 unsigned long long max_sectors = q->limits.max_zone_append_sectors;
225 return sprintf(page, "%llu\n", max_sectors << SECTOR_SHIFT);
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); \
280 blk_queue_flag_set(QUEUE_FLAG_##flag, q); \
282 blk_queue_flag_clear(QUEUE_FLAG_##flag, q); \
286 QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
287 QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
288 QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
289 #undef QUEUE_SYSFS_BIT_FNS
291 static ssize_t queue_zoned_show(struct request_queue *q, char *page)
293 switch (blk_queue_zoned_model(q)) {
295 return sprintf(page, "host-aware\n");
297 return sprintf(page, "host-managed\n");
299 return sprintf(page, "none\n");
303 static ssize_t queue_nr_zones_show(struct request_queue *q, char *page)
305 return queue_var_show(blk_queue_nr_zones(q), page);
308 static ssize_t queue_nomerges_show(struct request_queue *q, char *page)
310 return queue_var_show((blk_queue_nomerges(q) << 1) |
311 blk_queue_noxmerges(q), page);
314 static ssize_t queue_nomerges_store(struct request_queue *q, const char *page,
318 ssize_t ret = queue_var_store(&nm, page, count);
323 blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
324 blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
326 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, q);
328 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
333 static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page)
335 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
336 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags);
338 return queue_var_show(set << force, page);
342 queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
344 ssize_t ret = -EINVAL;
348 ret = queue_var_store(&val, page, count);
353 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
354 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
355 } else if (val == 1) {
356 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
357 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
358 } else if (val == 0) {
359 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
360 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
366 static ssize_t queue_poll_delay_show(struct request_queue *q, char *page)
370 if (q->poll_nsec == BLK_MQ_POLL_CLASSIC)
371 val = BLK_MQ_POLL_CLASSIC;
373 val = q->poll_nsec / 1000;
375 return sprintf(page, "%d\n", val);
378 static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page,
383 if (!q->mq_ops || !q->mq_ops->poll)
386 err = kstrtoint(page, 10, &val);
390 if (val == BLK_MQ_POLL_CLASSIC)
391 q->poll_nsec = BLK_MQ_POLL_CLASSIC;
393 q->poll_nsec = val * 1000;
400 static ssize_t queue_poll_show(struct request_queue *q, char *page)
402 return queue_var_show(test_bit(QUEUE_FLAG_POLL, &q->queue_flags), page);
405 static ssize_t queue_poll_store(struct request_queue *q, const char *page,
408 unsigned long poll_on;
411 if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL ||
412 !q->tag_set->map[HCTX_TYPE_POLL].nr_queues)
415 ret = queue_var_store(&poll_on, page, count);
420 blk_queue_flag_set(QUEUE_FLAG_POLL, q);
422 blk_queue_flag_clear(QUEUE_FLAG_POLL, q);
427 static ssize_t queue_io_timeout_show(struct request_queue *q, char *page)
429 return sprintf(page, "%u\n", jiffies_to_msecs(q->rq_timeout));
432 static ssize_t queue_io_timeout_store(struct request_queue *q, const char *page,
438 err = kstrtou32(page, 10, &val);
442 blk_queue_rq_timeout(q, msecs_to_jiffies(val));
447 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page)
452 return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000));
455 static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page,
462 ret = queue_var_store64(&val, page);
468 rqos = wbt_rq_qos(q);
476 val = wbt_default_latency_nsec(q);
480 if (wbt_get_min_lat(q) == val)
484 * Ensure that the queue is idled, in case the latency update
485 * ends up either enabling or disabling wbt completely. We can't
486 * have IO inflight if that happens.
488 blk_mq_freeze_queue(q);
489 blk_mq_quiesce_queue(q);
491 wbt_set_min_lat(q, val);
493 blk_mq_unquiesce_queue(q);
494 blk_mq_unfreeze_queue(q);
499 static ssize_t queue_wc_show(struct request_queue *q, char *page)
501 if (test_bit(QUEUE_FLAG_WC, &q->queue_flags))
502 return sprintf(page, "write back\n");
504 return sprintf(page, "write through\n");
507 static ssize_t queue_wc_store(struct request_queue *q, const char *page,
512 if (!strncmp(page, "write back", 10))
514 else if (!strncmp(page, "write through", 13) ||
515 !strncmp(page, "none", 4))
522 blk_queue_flag_set(QUEUE_FLAG_WC, q);
524 blk_queue_flag_clear(QUEUE_FLAG_WC, q);
529 static ssize_t queue_fua_show(struct request_queue *q, char *page)
531 return sprintf(page, "%u\n", test_bit(QUEUE_FLAG_FUA, &q->queue_flags));
534 static ssize_t queue_dax_show(struct request_queue *q, char *page)
536 return queue_var_show(blk_queue_dax(q), page);
539 static struct queue_sysfs_entry queue_requests_entry = {
540 .attr = {.name = "nr_requests", .mode = 0644 },
541 .show = queue_requests_show,
542 .store = queue_requests_store,
545 static struct queue_sysfs_entry queue_ra_entry = {
546 .attr = {.name = "read_ahead_kb", .mode = 0644 },
547 .show = queue_ra_show,
548 .store = queue_ra_store,
551 static struct queue_sysfs_entry queue_max_sectors_entry = {
552 .attr = {.name = "max_sectors_kb", .mode = 0644 },
553 .show = queue_max_sectors_show,
554 .store = queue_max_sectors_store,
557 static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
558 .attr = {.name = "max_hw_sectors_kb", .mode = 0444 },
559 .show = queue_max_hw_sectors_show,
562 static struct queue_sysfs_entry queue_max_segments_entry = {
563 .attr = {.name = "max_segments", .mode = 0444 },
564 .show = queue_max_segments_show,
567 static struct queue_sysfs_entry queue_max_discard_segments_entry = {
568 .attr = {.name = "max_discard_segments", .mode = 0444 },
569 .show = queue_max_discard_segments_show,
572 static struct queue_sysfs_entry queue_max_integrity_segments_entry = {
573 .attr = {.name = "max_integrity_segments", .mode = 0444 },
574 .show = queue_max_integrity_segments_show,
577 static struct queue_sysfs_entry queue_max_segment_size_entry = {
578 .attr = {.name = "max_segment_size", .mode = 0444 },
579 .show = queue_max_segment_size_show,
582 static struct queue_sysfs_entry queue_iosched_entry = {
583 .attr = {.name = "scheduler", .mode = 0644 },
584 .show = elv_iosched_show,
585 .store = elv_iosched_store,
588 static struct queue_sysfs_entry queue_hw_sector_size_entry = {
589 .attr = {.name = "hw_sector_size", .mode = 0444 },
590 .show = queue_logical_block_size_show,
593 static struct queue_sysfs_entry queue_logical_block_size_entry = {
594 .attr = {.name = "logical_block_size", .mode = 0444 },
595 .show = queue_logical_block_size_show,
598 static struct queue_sysfs_entry queue_physical_block_size_entry = {
599 .attr = {.name = "physical_block_size", .mode = 0444 },
600 .show = queue_physical_block_size_show,
603 static struct queue_sysfs_entry queue_chunk_sectors_entry = {
604 .attr = {.name = "chunk_sectors", .mode = 0444 },
605 .show = queue_chunk_sectors_show,
608 static struct queue_sysfs_entry queue_io_min_entry = {
609 .attr = {.name = "minimum_io_size", .mode = 0444 },
610 .show = queue_io_min_show,
613 static struct queue_sysfs_entry queue_io_opt_entry = {
614 .attr = {.name = "optimal_io_size", .mode = 0444 },
615 .show = queue_io_opt_show,
618 static struct queue_sysfs_entry queue_discard_granularity_entry = {
619 .attr = {.name = "discard_granularity", .mode = 0444 },
620 .show = queue_discard_granularity_show,
623 static struct queue_sysfs_entry queue_discard_max_hw_entry = {
624 .attr = {.name = "discard_max_hw_bytes", .mode = 0444 },
625 .show = queue_discard_max_hw_show,
628 static struct queue_sysfs_entry queue_discard_max_entry = {
629 .attr = {.name = "discard_max_bytes", .mode = 0644 },
630 .show = queue_discard_max_show,
631 .store = queue_discard_max_store,
634 static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
635 .attr = {.name = "discard_zeroes_data", .mode = 0444 },
636 .show = queue_discard_zeroes_data_show,
639 static struct queue_sysfs_entry queue_write_same_max_entry = {
640 .attr = {.name = "write_same_max_bytes", .mode = 0444 },
641 .show = queue_write_same_max_show,
644 static struct queue_sysfs_entry queue_write_zeroes_max_entry = {
645 .attr = {.name = "write_zeroes_max_bytes", .mode = 0444 },
646 .show = queue_write_zeroes_max_show,
649 static struct queue_sysfs_entry queue_zone_append_max_entry = {
650 .attr = {.name = "zone_append_max_bytes", .mode = 0444 },
651 .show = queue_zone_append_max_show,
654 static struct queue_sysfs_entry queue_nonrot_entry = {
655 .attr = {.name = "rotational", .mode = 0644 },
656 .show = queue_show_nonrot,
657 .store = queue_store_nonrot,
660 static struct queue_sysfs_entry queue_zoned_entry = {
661 .attr = {.name = "zoned", .mode = 0444 },
662 .show = queue_zoned_show,
665 static struct queue_sysfs_entry queue_nr_zones_entry = {
666 .attr = {.name = "nr_zones", .mode = 0444 },
667 .show = queue_nr_zones_show,
670 static struct queue_sysfs_entry queue_nomerges_entry = {
671 .attr = {.name = "nomerges", .mode = 0644 },
672 .show = queue_nomerges_show,
673 .store = queue_nomerges_store,
676 static struct queue_sysfs_entry queue_rq_affinity_entry = {
677 .attr = {.name = "rq_affinity", .mode = 0644 },
678 .show = queue_rq_affinity_show,
679 .store = queue_rq_affinity_store,
682 static struct queue_sysfs_entry queue_iostats_entry = {
683 .attr = {.name = "iostats", .mode = 0644 },
684 .show = queue_show_iostats,
685 .store = queue_store_iostats,
688 static struct queue_sysfs_entry queue_random_entry = {
689 .attr = {.name = "add_random", .mode = 0644 },
690 .show = queue_show_random,
691 .store = queue_store_random,
694 static struct queue_sysfs_entry queue_poll_entry = {
695 .attr = {.name = "io_poll", .mode = 0644 },
696 .show = queue_poll_show,
697 .store = queue_poll_store,
700 static struct queue_sysfs_entry queue_poll_delay_entry = {
701 .attr = {.name = "io_poll_delay", .mode = 0644 },
702 .show = queue_poll_delay_show,
703 .store = queue_poll_delay_store,
706 static struct queue_sysfs_entry queue_wc_entry = {
707 .attr = {.name = "write_cache", .mode = 0644 },
708 .show = queue_wc_show,
709 .store = queue_wc_store,
712 static struct queue_sysfs_entry queue_fua_entry = {
713 .attr = {.name = "fua", .mode = 0444 },
714 .show = queue_fua_show,
717 static struct queue_sysfs_entry queue_dax_entry = {
718 .attr = {.name = "dax", .mode = 0444 },
719 .show = queue_dax_show,
722 static struct queue_sysfs_entry queue_io_timeout_entry = {
723 .attr = {.name = "io_timeout", .mode = 0644 },
724 .show = queue_io_timeout_show,
725 .store = queue_io_timeout_store,
728 static struct queue_sysfs_entry queue_wb_lat_entry = {
729 .attr = {.name = "wbt_lat_usec", .mode = 0644 },
730 .show = queue_wb_lat_show,
731 .store = queue_wb_lat_store,
734 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
735 static struct queue_sysfs_entry throtl_sample_time_entry = {
736 .attr = {.name = "throttle_sample_time", .mode = 0644 },
737 .show = blk_throtl_sample_time_show,
738 .store = blk_throtl_sample_time_store,
742 static struct attribute *queue_attrs[] = {
743 &queue_requests_entry.attr,
744 &queue_ra_entry.attr,
745 &queue_max_hw_sectors_entry.attr,
746 &queue_max_sectors_entry.attr,
747 &queue_max_segments_entry.attr,
748 &queue_max_discard_segments_entry.attr,
749 &queue_max_integrity_segments_entry.attr,
750 &queue_max_segment_size_entry.attr,
751 &queue_iosched_entry.attr,
752 &queue_hw_sector_size_entry.attr,
753 &queue_logical_block_size_entry.attr,
754 &queue_physical_block_size_entry.attr,
755 &queue_chunk_sectors_entry.attr,
756 &queue_io_min_entry.attr,
757 &queue_io_opt_entry.attr,
758 &queue_discard_granularity_entry.attr,
759 &queue_discard_max_entry.attr,
760 &queue_discard_max_hw_entry.attr,
761 &queue_discard_zeroes_data_entry.attr,
762 &queue_write_same_max_entry.attr,
763 &queue_write_zeroes_max_entry.attr,
764 &queue_zone_append_max_entry.attr,
765 &queue_nonrot_entry.attr,
766 &queue_zoned_entry.attr,
767 &queue_nr_zones_entry.attr,
768 &queue_nomerges_entry.attr,
769 &queue_rq_affinity_entry.attr,
770 &queue_iostats_entry.attr,
771 &queue_random_entry.attr,
772 &queue_poll_entry.attr,
773 &queue_wc_entry.attr,
774 &queue_fua_entry.attr,
775 &queue_dax_entry.attr,
776 &queue_wb_lat_entry.attr,
777 &queue_poll_delay_entry.attr,
778 &queue_io_timeout_entry.attr,
779 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
780 &throtl_sample_time_entry.attr,
785 static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr,
788 struct request_queue *q =
789 container_of(kobj, struct request_queue, kobj);
791 if (attr == &queue_io_timeout_entry.attr &&
792 (!q->mq_ops || !q->mq_ops->timeout))
798 static struct attribute_group queue_attr_group = {
799 .attrs = queue_attrs,
800 .is_visible = queue_attr_visible,
804 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
807 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
809 struct queue_sysfs_entry *entry = to_queue(attr);
810 struct request_queue *q =
811 container_of(kobj, struct request_queue, kobj);
816 mutex_lock(&q->sysfs_lock);
817 res = entry->show(q, page);
818 mutex_unlock(&q->sysfs_lock);
823 queue_attr_store(struct kobject *kobj, struct attribute *attr,
824 const char *page, size_t length)
826 struct queue_sysfs_entry *entry = to_queue(attr);
827 struct request_queue *q;
833 q = container_of(kobj, struct request_queue, kobj);
834 mutex_lock(&q->sysfs_lock);
835 res = entry->store(q, page, length);
836 mutex_unlock(&q->sysfs_lock);
840 static void blk_free_queue_rcu(struct rcu_head *rcu_head)
842 struct request_queue *q = container_of(rcu_head, struct request_queue,
844 kmem_cache_free(blk_requestq_cachep, q);
847 /* Unconfigure the I/O scheduler and dissociate from the cgroup controller. */
848 static void blk_exit_queue(struct request_queue *q)
851 * Since the I/O scheduler exit code may access cgroup information,
852 * perform I/O scheduler exit before disassociating from the block
857 __elevator_exit(q, q->elevator);
862 * Remove all references to @q from the block cgroup controller before
863 * restoring @q->queue_lock to avoid that restoring this pointer causes
864 * e.g. blkcg_print_blkgs() to crash.
869 * Since the cgroup code may dereference the @q->backing_dev_info
870 * pointer, only decrease its reference count after having removed the
871 * association with the block cgroup controller.
873 bdi_put(q->backing_dev_info);
878 * __blk_release_queue - release a request queue
879 * @work: pointer to the release_work member of the request queue to be released
882 * This function is called when a block device is being unregistered. The
883 * process of releasing a request queue starts with blk_cleanup_queue, which
884 * set the appropriate flags and then calls blk_put_queue, that decrements
885 * the reference counter of the request queue. Once the reference counter
886 * of the request queue reaches zero, blk_release_queue is called to release
887 * all allocated resources of the request queue.
889 static void __blk_release_queue(struct work_struct *work)
891 struct request_queue *q = container_of(work, typeof(*q), release_work);
893 if (test_bit(QUEUE_FLAG_POLL_STATS, &q->queue_flags))
894 blk_stat_remove_callback(q, q->poll_cb);
895 blk_stat_free_callback(q->poll_cb);
897 blk_free_queue_stats(q->stats);
900 cancel_delayed_work_sync(&q->requeue_work);
904 blk_queue_free_zone_bitmaps(q);
909 blk_trace_shutdown(q);
912 blk_mq_debugfs_unregister(q);
914 bioset_exit(&q->bio_split);
916 ida_simple_remove(&blk_queue_ida, q->id);
917 call_rcu(&q->rcu_head, blk_free_queue_rcu);
920 static void blk_release_queue(struct kobject *kobj)
922 struct request_queue *q =
923 container_of(kobj, struct request_queue, kobj);
925 INIT_WORK(&q->release_work, __blk_release_queue);
926 schedule_work(&q->release_work);
929 static const struct sysfs_ops queue_sysfs_ops = {
930 .show = queue_attr_show,
931 .store = queue_attr_store,
934 struct kobj_type blk_queue_ktype = {
935 .sysfs_ops = &queue_sysfs_ops,
936 .release = blk_release_queue,
940 * blk_register_queue - register a block layer queue with sysfs
941 * @disk: Disk of which the request queue should be registered with sysfs.
943 int blk_register_queue(struct gendisk *disk)
946 struct device *dev = disk_to_dev(disk);
947 struct request_queue *q = disk->queue;
948 bool has_elevator = false;
953 WARN_ONCE(blk_queue_registered(q),
954 "%s is registering an already registered queue\n",
955 kobject_name(&dev->kobj));
958 * SCSI probing may synchronously create and destroy a lot of
959 * request_queues for non-existent devices. Shutting down a fully
960 * functional queue takes measureable wallclock time as RCU grace
961 * periods are involved. To avoid excessive latency in these
962 * cases, a request_queue starts out in a degraded mode which is
963 * faster to shut down and is made fully functional here as
964 * request_queues for non-existent devices never get registered.
966 if (!blk_queue_init_done(q)) {
967 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q);
968 percpu_ref_switch_to_percpu(&q->q_usage_counter);
971 ret = blk_trace_init_sysfs(dev);
975 mutex_lock(&q->sysfs_dir_lock);
977 ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
979 blk_trace_remove_sysfs(dev);
983 ret = sysfs_create_group(&q->kobj, &queue_attr_group);
985 blk_trace_remove_sysfs(dev);
986 kobject_del(&q->kobj);
987 kobject_put(&dev->kobj);
991 if (queue_is_mq(q)) {
992 __blk_mq_register_dev(dev, q);
993 blk_mq_debugfs_register(q);
996 mutex_lock(&q->sysfs_lock);
998 ret = elv_register_queue(q, false);
1000 mutex_unlock(&q->sysfs_lock);
1001 mutex_unlock(&q->sysfs_dir_lock);
1002 kobject_del(&q->kobj);
1003 blk_trace_remove_sysfs(dev);
1004 kobject_put(&dev->kobj);
1007 has_elevator = true;
1010 blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q);
1011 wbt_enable_default(q);
1012 blk_throtl_register_queue(q);
1014 /* Now everything is ready and send out KOBJ_ADD uevent */
1015 kobject_uevent(&q->kobj, KOBJ_ADD);
1017 kobject_uevent(&q->elevator->kobj, KOBJ_ADD);
1018 mutex_unlock(&q->sysfs_lock);
1022 mutex_unlock(&q->sysfs_dir_lock);
1025 EXPORT_SYMBOL_GPL(blk_register_queue);
1028 * blk_unregister_queue - counterpart of blk_register_queue()
1029 * @disk: Disk of which the request queue should be unregistered from sysfs.
1031 * Note: the caller is responsible for guaranteeing that this function is called
1032 * after blk_register_queue() has finished.
1034 void blk_unregister_queue(struct gendisk *disk)
1036 struct request_queue *q = disk->queue;
1041 /* Return early if disk->queue was never registered. */
1042 if (!blk_queue_registered(q))
1046 * Since sysfs_remove_dir() prevents adding new directory entries
1047 * before removal of existing entries starts, protect against
1048 * concurrent elv_iosched_store() calls.
1050 mutex_lock(&q->sysfs_lock);
1051 blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q);
1052 mutex_unlock(&q->sysfs_lock);
1054 mutex_lock(&q->sysfs_dir_lock);
1056 * Remove the sysfs attributes before unregistering the queue data
1057 * structures that can be modified through sysfs.
1060 blk_mq_unregister_dev(disk_to_dev(disk), q);
1062 kobject_uevent(&q->kobj, KOBJ_REMOVE);
1063 kobject_del(&q->kobj);
1064 blk_trace_remove_sysfs(disk_to_dev(disk));
1066 mutex_lock(&q->sysfs_lock);
1068 elv_unregister_queue(q);
1069 mutex_unlock(&q->sysfs_lock);
1070 mutex_unlock(&q->sysfs_dir_lock);
1072 kobject_put(&disk_to_dev(disk)->kobj);