2 * Copyright (C) 2016 Red Hat, Inc. All rights reserved.
4 * This file is released under the GPL.
10 #include <linux/elevator.h> /* for rq_end_sector() */
11 #include <linux/blk-mq.h>
13 #define DM_MSG_PREFIX "core-rq"
15 #define DM_MQ_NR_HW_QUEUES 1
16 #define DM_MQ_QUEUE_DEPTH 2048
17 static unsigned dm_mq_nr_hw_queues = DM_MQ_NR_HW_QUEUES;
18 static unsigned dm_mq_queue_depth = DM_MQ_QUEUE_DEPTH;
21 * Request-based DM's mempools' reserved IOs set by the user.
23 #define RESERVED_REQUEST_BASED_IOS 256
24 static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS;
26 #ifdef CONFIG_DM_MQ_DEFAULT
27 static bool use_blk_mq = true;
29 static bool use_blk_mq = false;
32 bool dm_use_blk_mq_default(void)
37 bool dm_use_blk_mq(struct mapped_device *md)
39 return md->use_blk_mq;
41 EXPORT_SYMBOL_GPL(dm_use_blk_mq);
43 unsigned dm_get_reserved_rq_based_ios(void)
45 return __dm_get_module_param(&reserved_rq_based_ios,
46 RESERVED_REQUEST_BASED_IOS, DM_RESERVED_MAX_IOS);
48 EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios);
50 static unsigned dm_get_blk_mq_nr_hw_queues(void)
52 return __dm_get_module_param(&dm_mq_nr_hw_queues, 1, 32);
55 static unsigned dm_get_blk_mq_queue_depth(void)
57 return __dm_get_module_param(&dm_mq_queue_depth,
58 DM_MQ_QUEUE_DEPTH, BLK_MQ_MAX_DEPTH);
61 int dm_request_based(struct mapped_device *md)
63 return blk_queue_stackable(md->queue);
66 static void dm_old_start_queue(struct request_queue *q)
70 spin_lock_irqsave(q->queue_lock, flags);
71 if (blk_queue_stopped(q))
73 spin_unlock_irqrestore(q->queue_lock, flags);
76 static void dm_mq_start_queue(struct request_queue *q)
78 blk_mq_start_stopped_hw_queues(q, true);
79 blk_mq_kick_requeue_list(q);
82 void dm_start_queue(struct request_queue *q)
85 dm_old_start_queue(q);
90 static void dm_old_stop_queue(struct request_queue *q)
94 spin_lock_irqsave(q->queue_lock, flags);
95 if (!blk_queue_stopped(q))
97 spin_unlock_irqrestore(q->queue_lock, flags);
100 static void dm_mq_stop_queue(struct request_queue *q)
102 if (blk_mq_queue_stopped(q))
105 blk_mq_quiesce_queue(q);
108 void dm_stop_queue(struct request_queue *q)
111 dm_old_stop_queue(q);
116 static struct dm_rq_target_io *alloc_old_rq_tio(struct mapped_device *md,
119 return mempool_alloc(md->io_pool, gfp_mask);
122 static void free_old_rq_tio(struct dm_rq_target_io *tio)
124 mempool_free(tio, tio->md->io_pool);
127 static struct request *alloc_old_clone_request(struct mapped_device *md,
130 return mempool_alloc(md->rq_pool, gfp_mask);
133 static void free_old_clone_request(struct mapped_device *md, struct request *rq)
135 mempool_free(rq, md->rq_pool);
139 * Partial completion handling for request-based dm
141 static void end_clone_bio(struct bio *clone)
143 struct dm_rq_clone_bio_info *info =
144 container_of(clone, struct dm_rq_clone_bio_info, clone);
145 struct dm_rq_target_io *tio = info->tio;
146 struct bio *bio = info->orig;
147 unsigned int nr_bytes = info->orig->bi_iter.bi_size;
148 int error = clone->bi_error;
154 * An error has already been detected on the request.
155 * Once error occurred, just let clone->end_io() handle
161 * Don't notice the error to the upper layer yet.
162 * The error handling decision is made by the target driver,
163 * when the request is completed.
170 * I/O for the bio successfully completed.
171 * Notice the data completion to the upper layer.
175 * bios are processed from the head of the list.
176 * So the completing bio should always be rq->bio.
177 * If it's not, something wrong is happening.
179 if (tio->orig->bio != bio)
180 DMERR("bio completion is going in the middle of the request");
183 * Update the original request.
184 * Do not use blk_end_request() here, because it may complete
185 * the original request before the clone, and break the ordering.
187 blk_update_request(tio->orig, 0, nr_bytes);
190 static struct dm_rq_target_io *tio_from_request(struct request *rq)
192 return (rq->q->mq_ops ? blk_mq_rq_to_pdu(rq) : rq->special);
195 static void rq_end_stats(struct mapped_device *md, struct request *orig)
197 if (unlikely(dm_stats_used(&md->stats))) {
198 struct dm_rq_target_io *tio = tio_from_request(orig);
199 tio->duration_jiffies = jiffies - tio->duration_jiffies;
200 dm_stats_account_io(&md->stats, rq_data_dir(orig),
201 blk_rq_pos(orig), tio->n_sectors, true,
202 tio->duration_jiffies, &tio->stats_aux);
207 * Don't touch any member of the md after calling this function because
208 * the md may be freed in dm_put() at the end of this function.
209 * Or do dm_get() before calling this function and dm_put() later.
211 static void rq_completed(struct mapped_device *md, int rw, bool run_queue)
213 atomic_dec(&md->pending[rw]);
215 /* nudge anyone waiting on suspend queue */
216 if (!md_in_flight(md))
220 * Run this off this callpath, as drivers could invoke end_io while
221 * inside their request_fn (and holding the queue lock). Calling
222 * back into ->request_fn() could deadlock attempting to grab the
225 if (!md->queue->mq_ops && run_queue)
226 blk_run_queue_async(md->queue);
229 * dm_put() must be at the end of this function. See the comment above
234 static void free_rq_clone(struct request *clone)
236 struct dm_rq_target_io *tio = clone->end_io_data;
237 struct mapped_device *md = tio->md;
239 blk_rq_unprep_clone(clone);
242 * It is possible for a clone_old_rq() allocated clone to
243 * get passed in -- it may not yet have a request_queue.
244 * This is known to occur if the error target replaces
245 * a multipath target that has a request_fn queue stacked
246 * on blk-mq queue(s).
248 if (clone->q && clone->q->mq_ops)
249 /* stacked on blk-mq queue(s) */
250 tio->ti->type->release_clone_rq(clone);
251 else if (!md->queue->mq_ops)
252 /* request_fn queue stacked on request_fn queue(s) */
253 free_old_clone_request(md, clone);
255 if (!md->queue->mq_ops)
256 free_old_rq_tio(tio);
260 * Complete the clone and the original request.
261 * Must be called without clone's queue lock held,
262 * see end_clone_request() for more details.
264 static void dm_end_request(struct request *clone, int error)
266 int rw = rq_data_dir(clone);
267 struct dm_rq_target_io *tio = clone->end_io_data;
268 struct mapped_device *md = tio->md;
269 struct request *rq = tio->orig;
271 if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
272 rq->errors = clone->errors;
273 rq->resid_len = clone->resid_len;
277 * We are using the sense buffer of the original
279 * So setting the length of the sense data is enough.
281 rq->sense_len = clone->sense_len;
284 free_rq_clone(clone);
285 rq_end_stats(md, rq);
287 blk_end_request_all(rq, error);
289 blk_mq_end_request(rq, error);
290 rq_completed(md, rw, true);
293 static void dm_unprep_request(struct request *rq)
295 struct dm_rq_target_io *tio = tio_from_request(rq);
296 struct request *clone = tio->clone;
298 if (!rq->q->mq_ops) {
300 rq->rq_flags &= ~RQF_DONTPREP;
304 free_rq_clone(clone);
305 else if (!tio->md->queue->mq_ops)
306 free_old_rq_tio(tio);
310 * Requeue the original request of a clone.
312 static void dm_old_requeue_request(struct request *rq)
314 struct request_queue *q = rq->q;
317 spin_lock_irqsave(q->queue_lock, flags);
318 blk_requeue_request(q, rq);
319 blk_run_queue_async(q);
320 spin_unlock_irqrestore(q->queue_lock, flags);
323 static void __dm_mq_kick_requeue_list(struct request_queue *q, unsigned long msecs)
325 blk_mq_delay_kick_requeue_list(q, msecs);
328 void dm_mq_kick_requeue_list(struct mapped_device *md)
330 __dm_mq_kick_requeue_list(dm_get_md_queue(md), 0);
332 EXPORT_SYMBOL(dm_mq_kick_requeue_list);
334 static void dm_mq_delay_requeue_request(struct request *rq, unsigned long msecs)
336 blk_mq_requeue_request(rq, false);
337 __dm_mq_kick_requeue_list(rq->q, msecs);
340 static void dm_requeue_original_request(struct dm_rq_target_io *tio, bool delay_requeue)
342 struct mapped_device *md = tio->md;
343 struct request *rq = tio->orig;
344 int rw = rq_data_dir(rq);
346 rq_end_stats(md, rq);
347 dm_unprep_request(rq);
350 dm_old_requeue_request(rq);
352 dm_mq_delay_requeue_request(rq, delay_requeue ? 5000 : 0);
354 rq_completed(md, rw, false);
357 static void dm_done(struct request *clone, int error, bool mapped)
360 struct dm_rq_target_io *tio = clone->end_io_data;
361 dm_request_endio_fn rq_end_io = NULL;
364 rq_end_io = tio->ti->type->rq_end_io;
366 if (mapped && rq_end_io)
367 r = rq_end_io(tio->ti, clone, error, &tio->info);
370 if (unlikely(r == -EREMOTEIO && (req_op(clone) == REQ_OP_WRITE_SAME) &&
371 !clone->q->limits.max_write_same_sectors))
372 disable_write_same(tio->md);
375 /* The target wants to complete the I/O */
376 dm_end_request(clone, r);
377 else if (r == DM_ENDIO_INCOMPLETE)
378 /* The target will handle the I/O */
380 else if (r == DM_ENDIO_REQUEUE)
381 /* The target wants to requeue the I/O */
382 dm_requeue_original_request(tio, false);
384 DMWARN("unimplemented target endio return value: %d", r);
390 * Request completion handler for request-based dm
392 static void dm_softirq_done(struct request *rq)
395 struct dm_rq_target_io *tio = tio_from_request(rq);
396 struct request *clone = tio->clone;
400 rq_end_stats(tio->md, rq);
401 rw = rq_data_dir(rq);
402 if (!rq->q->mq_ops) {
403 blk_end_request_all(rq, tio->error);
404 rq_completed(tio->md, rw, false);
405 free_old_rq_tio(tio);
407 blk_mq_end_request(rq, tio->error);
408 rq_completed(tio->md, rw, false);
413 if (rq->rq_flags & RQF_FAILED)
416 dm_done(clone, tio->error, mapped);
420 * Complete the clone and the original request with the error status
421 * through softirq context.
423 static void dm_complete_request(struct request *rq, int error)
425 struct dm_rq_target_io *tio = tio_from_request(rq);
429 blk_complete_request(rq);
431 blk_mq_complete_request(rq, error);
435 * Complete the not-mapped clone and the original request with the error status
436 * through softirq context.
437 * Target's rq_end_io() function isn't called.
438 * This may be used when the target's map_rq() or clone_and_map_rq() functions fail.
440 static void dm_kill_unmapped_request(struct request *rq, int error)
442 rq->rq_flags |= RQF_FAILED;
443 dm_complete_request(rq, error);
447 * Called with the clone's queue lock held (in the case of .request_fn)
449 static void end_clone_request(struct request *clone, int error)
451 struct dm_rq_target_io *tio = clone->end_io_data;
453 if (!clone->q->mq_ops) {
455 * For just cleaning up the information of the queue in which
456 * the clone was dispatched.
457 * The clone is *NOT* freed actually here because it is alloced
458 * from dm own mempool (RQF_ALLOCED isn't set).
460 __blk_put_request(clone->q, clone);
464 * Actual request completion is done in a softirq context which doesn't
465 * hold the clone's queue lock. Otherwise, deadlock could occur because:
466 * - another request may be submitted by the upper level driver
467 * of the stacking during the completion
468 * - the submission which requires queue lock may be done
469 * against this clone's queue
471 dm_complete_request(tio->orig, error);
474 static void dm_dispatch_clone_request(struct request *clone, struct request *rq)
478 if (blk_queue_io_stat(clone->q))
479 clone->rq_flags |= RQF_IO_STAT;
481 clone->start_time = jiffies;
482 r = blk_insert_cloned_request(clone->q, clone);
484 /* must complete clone in terms of original request */
485 dm_complete_request(rq, r);
488 static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig,
491 struct dm_rq_target_io *tio = data;
492 struct dm_rq_clone_bio_info *info =
493 container_of(bio, struct dm_rq_clone_bio_info, clone);
495 info->orig = bio_orig;
497 bio->bi_end_io = end_clone_bio;
502 static int setup_clone(struct request *clone, struct request *rq,
503 struct dm_rq_target_io *tio, gfp_t gfp_mask)
507 r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask,
508 dm_rq_bio_constructor, tio);
512 clone->cmd = rq->cmd;
513 clone->cmd_len = rq->cmd_len;
514 clone->sense = rq->sense;
515 clone->end_io = end_clone_request;
516 clone->end_io_data = tio;
523 static struct request *clone_old_rq(struct request *rq, struct mapped_device *md,
524 struct dm_rq_target_io *tio, gfp_t gfp_mask)
527 * Create clone for use with .request_fn request_queue
529 struct request *clone;
531 clone = alloc_old_clone_request(md, gfp_mask);
535 blk_rq_init(NULL, clone);
536 if (setup_clone(clone, rq, tio, gfp_mask)) {
538 free_old_clone_request(md, clone);
545 static void map_tio_request(struct kthread_work *work);
547 static void init_tio(struct dm_rq_target_io *tio, struct request *rq,
548 struct mapped_device *md)
556 * Avoid initializing info for blk-mq; it passes
557 * target-specific data through info.ptr
558 * (see: dm_mq_init_request)
560 if (!md->init_tio_pdu)
561 memset(&tio->info, 0, sizeof(tio->info));
562 if (md->kworker_task)
563 kthread_init_work(&tio->work, map_tio_request);
566 static struct dm_rq_target_io *dm_old_prep_tio(struct request *rq,
567 struct mapped_device *md,
570 struct dm_rq_target_io *tio;
572 struct dm_table *table;
574 tio = alloc_old_rq_tio(md, gfp_mask);
578 init_tio(tio, rq, md);
580 table = dm_get_live_table(md, &srcu_idx);
582 * Must clone a request if this .request_fn DM device
583 * is stacked on .request_fn device(s).
585 if (!dm_table_all_blk_mq_devices(table)) {
586 if (!clone_old_rq(rq, md, tio, gfp_mask)) {
587 dm_put_live_table(md, srcu_idx);
588 free_old_rq_tio(tio);
592 dm_put_live_table(md, srcu_idx);
598 * Called with the queue lock held.
600 static int dm_old_prep_fn(struct request_queue *q, struct request *rq)
602 struct mapped_device *md = q->queuedata;
603 struct dm_rq_target_io *tio;
605 if (unlikely(rq->special)) {
606 DMWARN("Already has something in rq->special.");
610 tio = dm_old_prep_tio(rq, md, GFP_ATOMIC);
612 return BLKPREP_DEFER;
615 rq->rq_flags |= RQF_DONTPREP;
622 * DM_MAPIO_* : the request has been processed as indicated
623 * DM_MAPIO_REQUEUE : the original request needs to be immediately requeued
624 * < 0 : the request was completed due to failure
626 static int map_request(struct dm_rq_target_io *tio)
629 struct dm_target *ti = tio->ti;
630 struct mapped_device *md = tio->md;
631 struct request *rq = tio->orig;
632 struct request *clone = NULL;
636 r = ti->type->map_rq(ti, clone, &tio->info);
637 if (r == DM_MAPIO_DELAY_REQUEUE)
638 return DM_MAPIO_REQUEUE; /* .request_fn requeue is always immediate */
640 r = ti->type->clone_and_map_rq(ti, rq, &tio->info, &clone);
642 /* The target wants to complete the I/O */
643 dm_kill_unmapped_request(rq, r);
646 if (r == DM_MAPIO_REMAPPED &&
647 setup_clone(clone, rq, tio, GFP_ATOMIC)) {
649 ti->type->release_clone_rq(clone);
650 return DM_MAPIO_REQUEUE;
655 case DM_MAPIO_SUBMITTED:
656 /* The target has taken the I/O to submit by itself later */
658 case DM_MAPIO_REMAPPED:
659 /* The target has remapped the I/O so dispatch it */
660 trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)),
662 dm_dispatch_clone_request(clone, rq);
664 case DM_MAPIO_REQUEUE:
665 /* The target wants to requeue the I/O */
667 case DM_MAPIO_DELAY_REQUEUE:
668 /* The target wants to requeue the I/O after a delay */
669 dm_requeue_original_request(tio, true);
673 DMWARN("unimplemented target map return value: %d", r);
677 /* The target wants to complete the I/O */
678 dm_kill_unmapped_request(rq, r);
684 static void dm_start_request(struct mapped_device *md, struct request *orig)
686 if (!orig->q->mq_ops)
687 blk_start_request(orig);
689 blk_mq_start_request(orig);
690 atomic_inc(&md->pending[rq_data_dir(orig)]);
692 if (md->seq_rq_merge_deadline_usecs) {
693 md->last_rq_pos = rq_end_sector(orig);
694 md->last_rq_rw = rq_data_dir(orig);
695 md->last_rq_start_time = ktime_get();
698 if (unlikely(dm_stats_used(&md->stats))) {
699 struct dm_rq_target_io *tio = tio_from_request(orig);
700 tio->duration_jiffies = jiffies;
701 tio->n_sectors = blk_rq_sectors(orig);
702 dm_stats_account_io(&md->stats, rq_data_dir(orig),
703 blk_rq_pos(orig), tio->n_sectors, false, 0,
708 * Hold the md reference here for the in-flight I/O.
709 * We can't rely on the reference count by device opener,
710 * because the device may be closed during the request completion
711 * when all bios are completed.
712 * See the comment in rq_completed() too.
717 static void map_tio_request(struct kthread_work *work)
719 struct dm_rq_target_io *tio = container_of(work, struct dm_rq_target_io, work);
721 if (map_request(tio) == DM_MAPIO_REQUEUE)
722 dm_requeue_original_request(tio, false);
725 ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf)
727 return sprintf(buf, "%u\n", md->seq_rq_merge_deadline_usecs);
730 #define MAX_SEQ_RQ_MERGE_DEADLINE_USECS 100000
732 ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
733 const char *buf, size_t count)
737 if (dm_get_md_type(md) != DM_TYPE_REQUEST_BASED)
740 if (kstrtouint(buf, 10, &deadline))
743 if (deadline > MAX_SEQ_RQ_MERGE_DEADLINE_USECS)
744 deadline = MAX_SEQ_RQ_MERGE_DEADLINE_USECS;
746 md->seq_rq_merge_deadline_usecs = deadline;
751 static bool dm_old_request_peeked_before_merge_deadline(struct mapped_device *md)
755 if (!md->seq_rq_merge_deadline_usecs)
758 kt_deadline = ns_to_ktime((u64)md->seq_rq_merge_deadline_usecs * NSEC_PER_USEC);
759 kt_deadline = ktime_add_safe(md->last_rq_start_time, kt_deadline);
761 return !ktime_after(ktime_get(), kt_deadline);
765 * q->request_fn for old request-based dm.
766 * Called with the queue lock held.
768 static void dm_old_request_fn(struct request_queue *q)
770 struct mapped_device *md = q->queuedata;
771 struct dm_target *ti = md->immutable_target;
773 struct dm_rq_target_io *tio;
778 struct dm_table *map = dm_get_live_table(md, &srcu_idx);
780 ti = dm_table_find_target(map, pos);
781 dm_put_live_table(md, srcu_idx);
785 * For suspend, check blk_queue_stopped() and increment
786 * ->pending within a single queue_lock not to increment the
787 * number of in-flight I/Os after the queue is stopped in
790 while (!blk_queue_stopped(q)) {
791 rq = blk_peek_request(q);
795 /* always use block 0 to find the target for flushes for now */
797 if (req_op(rq) != REQ_OP_FLUSH)
798 pos = blk_rq_pos(rq);
800 if ((dm_old_request_peeked_before_merge_deadline(md) &&
801 md_in_flight(md) && rq->bio && rq->bio->bi_vcnt == 1 &&
802 md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) ||
803 (ti->type->busy && ti->type->busy(ti))) {
804 blk_delay_queue(q, 10);
808 dm_start_request(md, rq);
810 tio = tio_from_request(rq);
811 /* Establish tio->ti before queuing work (map_tio_request) */
813 kthread_queue_work(&md->kworker, &tio->work);
814 BUG_ON(!irqs_disabled());
819 * Fully initialize a .request_fn request-based queue.
821 int dm_old_init_request_queue(struct mapped_device *md)
823 /* Fully initialize the queue */
824 if (!blk_init_allocated_queue(md->queue, dm_old_request_fn, NULL))
827 /* disable dm_old_request_fn's merge heuristic by default */
828 md->seq_rq_merge_deadline_usecs = 0;
830 dm_init_normal_md_queue(md);
831 blk_queue_softirq_done(md->queue, dm_softirq_done);
832 blk_queue_prep_rq(md->queue, dm_old_prep_fn);
834 /* Initialize the request-based DM worker thread */
835 kthread_init_worker(&md->kworker);
836 md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker,
837 "kdmwork-%s", dm_device_name(md));
838 if (IS_ERR(md->kworker_task)) {
839 int error = PTR_ERR(md->kworker_task);
840 md->kworker_task = NULL;
844 elv_register_queue(md->queue);
849 static int dm_mq_init_request(void *data, struct request *rq,
850 unsigned int hctx_idx, unsigned int request_idx,
851 unsigned int numa_node)
853 struct mapped_device *md = data;
854 struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
857 * Must initialize md member of tio, otherwise it won't
858 * be available in dm_mq_queue_rq.
862 if (md->init_tio_pdu) {
863 /* target-specific per-io data is immediately after the tio */
864 tio->info.ptr = tio + 1;
870 static int dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
871 const struct blk_mq_queue_data *bd)
873 struct request *rq = bd->rq;
874 struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
875 struct mapped_device *md = tio->md;
876 struct dm_target *ti = md->immutable_target;
880 struct dm_table *map = dm_get_live_table(md, &srcu_idx);
882 ti = dm_table_find_target(map, 0);
883 dm_put_live_table(md, srcu_idx);
886 if (ti->type->busy && ti->type->busy(ti))
887 return BLK_MQ_RQ_QUEUE_BUSY;
889 dm_start_request(md, rq);
891 /* Init tio using md established in .init_request */
892 init_tio(tio, rq, md);
895 * Establish tio->ti before calling map_request().
899 /* Direct call is fine since .queue_rq allows allocations */
900 if (map_request(tio) == DM_MAPIO_REQUEUE) {
901 /* Undo dm_start_request() before requeuing */
902 rq_end_stats(md, rq);
903 rq_completed(md, rq_data_dir(rq), false);
904 return BLK_MQ_RQ_QUEUE_BUSY;
907 return BLK_MQ_RQ_QUEUE_OK;
910 static struct blk_mq_ops dm_mq_ops = {
911 .queue_rq = dm_mq_queue_rq,
912 .complete = dm_softirq_done,
913 .init_request = dm_mq_init_request,
916 int dm_mq_init_request_queue(struct mapped_device *md, struct dm_table *t)
918 struct request_queue *q;
919 struct dm_target *immutable_tgt;
922 if (!dm_table_all_blk_mq_devices(t)) {
923 DMERR("request-based dm-mq may only be stacked on blk-mq device(s)");
927 md->tag_set = kzalloc_node(sizeof(struct blk_mq_tag_set), GFP_KERNEL, md->numa_node_id);
931 md->tag_set->ops = &dm_mq_ops;
932 md->tag_set->queue_depth = dm_get_blk_mq_queue_depth();
933 md->tag_set->numa_node = md->numa_node_id;
934 md->tag_set->flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE;
935 md->tag_set->nr_hw_queues = dm_get_blk_mq_nr_hw_queues();
936 md->tag_set->driver_data = md;
938 md->tag_set->cmd_size = sizeof(struct dm_rq_target_io);
939 immutable_tgt = dm_table_get_immutable_target(t);
940 if (immutable_tgt && immutable_tgt->per_io_data_size) {
941 /* any target-specific per-io data is immediately after the tio */
942 md->tag_set->cmd_size += immutable_tgt->per_io_data_size;
943 md->init_tio_pdu = true;
946 err = blk_mq_alloc_tag_set(md->tag_set);
948 goto out_kfree_tag_set;
950 q = blk_mq_init_allocated_queue(md->tag_set, md->queue);
955 dm_init_md_queue(md);
957 /* backfill 'mq' sysfs registration normally done in blk_register_queue */
958 blk_mq_register_dev(disk_to_dev(md->disk), q);
963 blk_mq_free_tag_set(md->tag_set);
970 void dm_mq_cleanup_mapped_device(struct mapped_device *md)
973 blk_mq_free_tag_set(md->tag_set);
978 module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR);
979 MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools");
981 module_param(use_blk_mq, bool, S_IRUGO | S_IWUSR);
982 MODULE_PARM_DESC(use_blk_mq, "Use block multiqueue for request-based DM devices");
984 module_param(dm_mq_nr_hw_queues, uint, S_IRUGO | S_IWUSR);
985 MODULE_PARM_DESC(dm_mq_nr_hw_queues, "Number of hardware queues for request-based dm-mq devices");
987 module_param(dm_mq_queue_depth, uint, S_IRUGO | S_IWUSR);
988 MODULE_PARM_DESC(dm_mq_queue_depth, "Queue depth for request-based dm-mq devices");