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![Christoph Hellwig](/assets/img/avatar_default.png)
We already have a queue_is_rq_based helper to check if a request_queue is request based, so we can remove the flag for it. Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
850 lines
21 KiB
C
850 lines
21 KiB
C
/*
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* Copyright (C) 2016 Red Hat, Inc. All rights reserved.
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*
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* This file is released under the GPL.
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*/
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#include "dm-core.h"
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#include "dm-rq.h"
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#include <linux/elevator.h> /* for rq_end_sector() */
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#include <linux/blk-mq.h>
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#define DM_MSG_PREFIX "core-rq"
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#define DM_MQ_NR_HW_QUEUES 1
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#define DM_MQ_QUEUE_DEPTH 2048
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static unsigned dm_mq_nr_hw_queues = DM_MQ_NR_HW_QUEUES;
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static unsigned dm_mq_queue_depth = DM_MQ_QUEUE_DEPTH;
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/*
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* Request-based DM's mempools' reserved IOs set by the user.
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*/
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#define RESERVED_REQUEST_BASED_IOS 256
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static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS;
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static bool use_blk_mq = IS_ENABLED(CONFIG_DM_MQ_DEFAULT);
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bool dm_use_blk_mq_default(void)
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{
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return use_blk_mq;
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}
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bool dm_use_blk_mq(struct mapped_device *md)
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{
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return md->use_blk_mq;
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}
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EXPORT_SYMBOL_GPL(dm_use_blk_mq);
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unsigned dm_get_reserved_rq_based_ios(void)
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{
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return __dm_get_module_param(&reserved_rq_based_ios,
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RESERVED_REQUEST_BASED_IOS, DM_RESERVED_MAX_IOS);
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}
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EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios);
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static unsigned dm_get_blk_mq_nr_hw_queues(void)
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{
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return __dm_get_module_param(&dm_mq_nr_hw_queues, 1, 32);
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}
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static unsigned dm_get_blk_mq_queue_depth(void)
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{
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return __dm_get_module_param(&dm_mq_queue_depth,
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DM_MQ_QUEUE_DEPTH, BLK_MQ_MAX_DEPTH);
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}
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int dm_request_based(struct mapped_device *md)
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{
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return queue_is_rq_based(md->queue);
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}
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static void dm_old_start_queue(struct request_queue *q)
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{
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unsigned long flags;
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spin_lock_irqsave(q->queue_lock, flags);
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if (blk_queue_stopped(q))
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blk_start_queue(q);
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spin_unlock_irqrestore(q->queue_lock, flags);
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}
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static void dm_mq_start_queue(struct request_queue *q)
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{
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blk_mq_unquiesce_queue(q);
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blk_mq_kick_requeue_list(q);
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}
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void dm_start_queue(struct request_queue *q)
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{
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if (!q->mq_ops)
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dm_old_start_queue(q);
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else
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dm_mq_start_queue(q);
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}
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static void dm_old_stop_queue(struct request_queue *q)
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{
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unsigned long flags;
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spin_lock_irqsave(q->queue_lock, flags);
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if (!blk_queue_stopped(q))
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blk_stop_queue(q);
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spin_unlock_irqrestore(q->queue_lock, flags);
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}
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static void dm_mq_stop_queue(struct request_queue *q)
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{
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if (blk_mq_queue_stopped(q))
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return;
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blk_mq_quiesce_queue(q);
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}
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void dm_stop_queue(struct request_queue *q)
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{
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if (!q->mq_ops)
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dm_old_stop_queue(q);
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else
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dm_mq_stop_queue(q);
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}
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/*
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* Partial completion handling for request-based dm
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*/
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static void end_clone_bio(struct bio *clone)
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{
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struct dm_rq_clone_bio_info *info =
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container_of(clone, struct dm_rq_clone_bio_info, clone);
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struct dm_rq_target_io *tio = info->tio;
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unsigned int nr_bytes = info->orig->bi_iter.bi_size;
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blk_status_t error = clone->bi_status;
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bool is_last = !clone->bi_next;
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bio_put(clone);
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if (tio->error)
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/*
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* An error has already been detected on the request.
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* Once error occurred, just let clone->end_io() handle
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* the remainder.
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*/
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return;
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else if (error) {
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/*
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* Don't notice the error to the upper layer yet.
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* The error handling decision is made by the target driver,
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* when the request is completed.
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*/
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tio->error = error;
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goto exit;
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}
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/*
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* I/O for the bio successfully completed.
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* Notice the data completion to the upper layer.
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*/
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tio->completed += nr_bytes;
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/*
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* Update the original request.
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* Do not use blk_end_request() here, because it may complete
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* the original request before the clone, and break the ordering.
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*/
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if (is_last)
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exit:
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blk_update_request(tio->orig, BLK_STS_OK, tio->completed);
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}
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static struct dm_rq_target_io *tio_from_request(struct request *rq)
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{
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return blk_mq_rq_to_pdu(rq);
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}
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static void rq_end_stats(struct mapped_device *md, struct request *orig)
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{
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if (unlikely(dm_stats_used(&md->stats))) {
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struct dm_rq_target_io *tio = tio_from_request(orig);
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tio->duration_jiffies = jiffies - tio->duration_jiffies;
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dm_stats_account_io(&md->stats, rq_data_dir(orig),
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blk_rq_pos(orig), tio->n_sectors, true,
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tio->duration_jiffies, &tio->stats_aux);
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}
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}
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/*
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* Don't touch any member of the md after calling this function because
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* the md may be freed in dm_put() at the end of this function.
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* Or do dm_get() before calling this function and dm_put() later.
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*/
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static void rq_completed(struct mapped_device *md, int rw, bool run_queue)
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{
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struct request_queue *q = md->queue;
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unsigned long flags;
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atomic_dec(&md->pending[rw]);
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/* nudge anyone waiting on suspend queue */
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if (!md_in_flight(md))
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wake_up(&md->wait);
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/*
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* Run this off this callpath, as drivers could invoke end_io while
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* inside their request_fn (and holding the queue lock). Calling
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* back into ->request_fn() could deadlock attempting to grab the
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* queue lock again.
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*/
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if (!q->mq_ops && run_queue) {
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spin_lock_irqsave(q->queue_lock, flags);
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blk_run_queue_async(q);
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spin_unlock_irqrestore(q->queue_lock, flags);
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}
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/*
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* dm_put() must be at the end of this function. See the comment above
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*/
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dm_put(md);
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}
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/*
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* Complete the clone and the original request.
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* Must be called without clone's queue lock held,
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* see end_clone_request() for more details.
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*/
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static void dm_end_request(struct request *clone, blk_status_t error)
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{
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int rw = rq_data_dir(clone);
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struct dm_rq_target_io *tio = clone->end_io_data;
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struct mapped_device *md = tio->md;
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struct request *rq = tio->orig;
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blk_rq_unprep_clone(clone);
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tio->ti->type->release_clone_rq(clone);
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rq_end_stats(md, rq);
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if (!rq->q->mq_ops)
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blk_end_request_all(rq, error);
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else
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blk_mq_end_request(rq, error);
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rq_completed(md, rw, true);
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}
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/*
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* Requeue the original request of a clone.
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*/
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static void dm_old_requeue_request(struct request *rq, unsigned long delay_ms)
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{
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struct request_queue *q = rq->q;
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unsigned long flags;
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spin_lock_irqsave(q->queue_lock, flags);
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blk_requeue_request(q, rq);
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blk_delay_queue(q, delay_ms);
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spin_unlock_irqrestore(q->queue_lock, flags);
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}
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static void __dm_mq_kick_requeue_list(struct request_queue *q, unsigned long msecs)
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{
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blk_mq_delay_kick_requeue_list(q, msecs);
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}
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void dm_mq_kick_requeue_list(struct mapped_device *md)
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{
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__dm_mq_kick_requeue_list(dm_get_md_queue(md), 0);
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}
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EXPORT_SYMBOL(dm_mq_kick_requeue_list);
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static void dm_mq_delay_requeue_request(struct request *rq, unsigned long msecs)
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{
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blk_mq_requeue_request(rq, false);
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__dm_mq_kick_requeue_list(rq->q, msecs);
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}
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static void dm_requeue_original_request(struct dm_rq_target_io *tio, bool delay_requeue)
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{
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struct mapped_device *md = tio->md;
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struct request *rq = tio->orig;
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int rw = rq_data_dir(rq);
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unsigned long delay_ms = delay_requeue ? 100 : 0;
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rq_end_stats(md, rq);
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if (tio->clone) {
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blk_rq_unprep_clone(tio->clone);
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tio->ti->type->release_clone_rq(tio->clone);
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}
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if (!rq->q->mq_ops)
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dm_old_requeue_request(rq, delay_ms);
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else
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dm_mq_delay_requeue_request(rq, delay_ms);
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rq_completed(md, rw, false);
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}
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static void dm_done(struct request *clone, blk_status_t error, bool mapped)
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{
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int r = DM_ENDIO_DONE;
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struct dm_rq_target_io *tio = clone->end_io_data;
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dm_request_endio_fn rq_end_io = NULL;
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if (tio->ti) {
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rq_end_io = tio->ti->type->rq_end_io;
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if (mapped && rq_end_io)
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r = rq_end_io(tio->ti, clone, error, &tio->info);
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}
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if (unlikely(error == BLK_STS_TARGET)) {
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if (req_op(clone) == REQ_OP_WRITE_SAME &&
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!clone->q->limits.max_write_same_sectors)
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disable_write_same(tio->md);
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if (req_op(clone) == REQ_OP_WRITE_ZEROES &&
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!clone->q->limits.max_write_zeroes_sectors)
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disable_write_zeroes(tio->md);
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}
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switch (r) {
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case DM_ENDIO_DONE:
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/* The target wants to complete the I/O */
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dm_end_request(clone, error);
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break;
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case DM_ENDIO_INCOMPLETE:
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/* The target will handle the I/O */
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return;
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case DM_ENDIO_REQUEUE:
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/* The target wants to requeue the I/O */
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dm_requeue_original_request(tio, false);
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break;
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default:
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DMWARN("unimplemented target endio return value: %d", r);
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BUG();
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}
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}
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/*
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* Request completion handler for request-based dm
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*/
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static void dm_softirq_done(struct request *rq)
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{
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bool mapped = true;
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struct dm_rq_target_io *tio = tio_from_request(rq);
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struct request *clone = tio->clone;
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int rw;
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if (!clone) {
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struct mapped_device *md = tio->md;
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rq_end_stats(md, rq);
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rw = rq_data_dir(rq);
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if (!rq->q->mq_ops)
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blk_end_request_all(rq, tio->error);
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else
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blk_mq_end_request(rq, tio->error);
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rq_completed(md, rw, false);
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return;
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}
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if (rq->rq_flags & RQF_FAILED)
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mapped = false;
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dm_done(clone, tio->error, mapped);
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}
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/*
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* Complete the clone and the original request with the error status
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* through softirq context.
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*/
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static void dm_complete_request(struct request *rq, blk_status_t error)
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{
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struct dm_rq_target_io *tio = tio_from_request(rq);
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tio->error = error;
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if (!rq->q->mq_ops)
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blk_complete_request(rq);
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else
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blk_mq_complete_request(rq);
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}
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/*
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* Complete the not-mapped clone and the original request with the error status
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* through softirq context.
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* Target's rq_end_io() function isn't called.
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* This may be used when the target's map_rq() or clone_and_map_rq() functions fail.
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*/
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static void dm_kill_unmapped_request(struct request *rq, blk_status_t error)
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{
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rq->rq_flags |= RQF_FAILED;
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dm_complete_request(rq, error);
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}
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/*
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* Called with the clone's queue lock held (in the case of .request_fn)
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*/
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static void end_clone_request(struct request *clone, blk_status_t error)
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{
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struct dm_rq_target_io *tio = clone->end_io_data;
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/*
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* Actual request completion is done in a softirq context which doesn't
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* hold the clone's queue lock. Otherwise, deadlock could occur because:
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* - another request may be submitted by the upper level driver
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* of the stacking during the completion
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* - the submission which requires queue lock may be done
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* against this clone's queue
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*/
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dm_complete_request(tio->orig, error);
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}
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static void dm_dispatch_clone_request(struct request *clone, struct request *rq)
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{
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blk_status_t r;
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if (blk_queue_io_stat(clone->q))
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clone->rq_flags |= RQF_IO_STAT;
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clone->start_time = jiffies;
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r = blk_insert_cloned_request(clone->q, clone);
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if (r)
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/* must complete clone in terms of original request */
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dm_complete_request(rq, r);
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}
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static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig,
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void *data)
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{
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struct dm_rq_target_io *tio = data;
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struct dm_rq_clone_bio_info *info =
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container_of(bio, struct dm_rq_clone_bio_info, clone);
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info->orig = bio_orig;
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info->tio = tio;
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bio->bi_end_io = end_clone_bio;
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return 0;
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}
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static int setup_clone(struct request *clone, struct request *rq,
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struct dm_rq_target_io *tio, gfp_t gfp_mask)
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{
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int r;
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r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask,
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dm_rq_bio_constructor, tio);
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if (r)
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return r;
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clone->end_io = end_clone_request;
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clone->end_io_data = tio;
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tio->clone = clone;
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return 0;
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}
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static void map_tio_request(struct kthread_work *work);
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static void init_tio(struct dm_rq_target_io *tio, struct request *rq,
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struct mapped_device *md)
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{
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tio->md = md;
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tio->ti = NULL;
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tio->clone = NULL;
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tio->orig = rq;
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tio->error = 0;
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tio->completed = 0;
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/*
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* Avoid initializing info for blk-mq; it passes
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* target-specific data through info.ptr
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* (see: dm_mq_init_request)
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*/
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if (!md->init_tio_pdu)
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memset(&tio->info, 0, sizeof(tio->info));
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if (md->kworker_task)
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kthread_init_work(&tio->work, map_tio_request);
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}
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/*
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* Returns:
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* DM_MAPIO_* : the request has been processed as indicated
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* DM_MAPIO_REQUEUE : the original request needs to be immediately requeued
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* < 0 : the request was completed due to failure
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*/
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static int map_request(struct dm_rq_target_io *tio)
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{
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int r;
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struct dm_target *ti = tio->ti;
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struct mapped_device *md = tio->md;
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struct request *rq = tio->orig;
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struct request *clone = NULL;
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r = ti->type->clone_and_map_rq(ti, rq, &tio->info, &clone);
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switch (r) {
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case DM_MAPIO_SUBMITTED:
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/* The target has taken the I/O to submit by itself later */
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break;
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case DM_MAPIO_REMAPPED:
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if (setup_clone(clone, rq, tio, GFP_ATOMIC)) {
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/* -ENOMEM */
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ti->type->release_clone_rq(clone);
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return DM_MAPIO_REQUEUE;
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}
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/* The target has remapped the I/O so dispatch it */
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trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)),
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blk_rq_pos(rq));
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dm_dispatch_clone_request(clone, rq);
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break;
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case DM_MAPIO_REQUEUE:
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/* The target wants to requeue the I/O */
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break;
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case DM_MAPIO_DELAY_REQUEUE:
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/* The target wants to requeue the I/O after a delay */
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dm_requeue_original_request(tio, true);
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break;
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case DM_MAPIO_KILL:
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/* The target wants to complete the I/O */
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dm_kill_unmapped_request(rq, BLK_STS_IOERR);
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break;
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|
default:
|
|
DMWARN("unimplemented target map return value: %d", r);
|
|
BUG();
|
|
}
|
|
|
|
return r;
|
|
}
|
|
|
|
static void dm_start_request(struct mapped_device *md, struct request *orig)
|
|
{
|
|
if (!orig->q->mq_ops)
|
|
blk_start_request(orig);
|
|
else
|
|
blk_mq_start_request(orig);
|
|
atomic_inc(&md->pending[rq_data_dir(orig)]);
|
|
|
|
if (md->seq_rq_merge_deadline_usecs) {
|
|
md->last_rq_pos = rq_end_sector(orig);
|
|
md->last_rq_rw = rq_data_dir(orig);
|
|
md->last_rq_start_time = ktime_get();
|
|
}
|
|
|
|
if (unlikely(dm_stats_used(&md->stats))) {
|
|
struct dm_rq_target_io *tio = tio_from_request(orig);
|
|
tio->duration_jiffies = jiffies;
|
|
tio->n_sectors = blk_rq_sectors(orig);
|
|
dm_stats_account_io(&md->stats, rq_data_dir(orig),
|
|
blk_rq_pos(orig), tio->n_sectors, false, 0,
|
|
&tio->stats_aux);
|
|
}
|
|
|
|
/*
|
|
* Hold the md reference here for the in-flight I/O.
|
|
* We can't rely on the reference count by device opener,
|
|
* because the device may be closed during the request completion
|
|
* when all bios are completed.
|
|
* See the comment in rq_completed() too.
|
|
*/
|
|
dm_get(md);
|
|
}
|
|
|
|
static int __dm_rq_init_rq(struct mapped_device *md, struct request *rq)
|
|
{
|
|
struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
|
|
|
|
/*
|
|
* Must initialize md member of tio, otherwise it won't
|
|
* be available in dm_mq_queue_rq.
|
|
*/
|
|
tio->md = md;
|
|
|
|
if (md->init_tio_pdu) {
|
|
/* target-specific per-io data is immediately after the tio */
|
|
tio->info.ptr = tio + 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dm_rq_init_rq(struct request_queue *q, struct request *rq, gfp_t gfp)
|
|
{
|
|
return __dm_rq_init_rq(q->rq_alloc_data, rq);
|
|
}
|
|
|
|
static void map_tio_request(struct kthread_work *work)
|
|
{
|
|
struct dm_rq_target_io *tio = container_of(work, struct dm_rq_target_io, work);
|
|
|
|
if (map_request(tio) == DM_MAPIO_REQUEUE)
|
|
dm_requeue_original_request(tio, false);
|
|
}
|
|
|
|
ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf)
|
|
{
|
|
return sprintf(buf, "%u\n", md->seq_rq_merge_deadline_usecs);
|
|
}
|
|
|
|
#define MAX_SEQ_RQ_MERGE_DEADLINE_USECS 100000
|
|
|
|
ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
|
|
const char *buf, size_t count)
|
|
{
|
|
unsigned deadline;
|
|
|
|
if (dm_get_md_type(md) != DM_TYPE_REQUEST_BASED)
|
|
return count;
|
|
|
|
if (kstrtouint(buf, 10, &deadline))
|
|
return -EINVAL;
|
|
|
|
if (deadline > MAX_SEQ_RQ_MERGE_DEADLINE_USECS)
|
|
deadline = MAX_SEQ_RQ_MERGE_DEADLINE_USECS;
|
|
|
|
md->seq_rq_merge_deadline_usecs = deadline;
|
|
|
|
return count;
|
|
}
|
|
|
|
static bool dm_old_request_peeked_before_merge_deadline(struct mapped_device *md)
|
|
{
|
|
ktime_t kt_deadline;
|
|
|
|
if (!md->seq_rq_merge_deadline_usecs)
|
|
return false;
|
|
|
|
kt_deadline = ns_to_ktime((u64)md->seq_rq_merge_deadline_usecs * NSEC_PER_USEC);
|
|
kt_deadline = ktime_add_safe(md->last_rq_start_time, kt_deadline);
|
|
|
|
return !ktime_after(ktime_get(), kt_deadline);
|
|
}
|
|
|
|
/*
|
|
* q->request_fn for old request-based dm.
|
|
* Called with the queue lock held.
|
|
*/
|
|
static void dm_old_request_fn(struct request_queue *q)
|
|
{
|
|
struct mapped_device *md = q->queuedata;
|
|
struct dm_target *ti = md->immutable_target;
|
|
struct request *rq;
|
|
struct dm_rq_target_io *tio;
|
|
sector_t pos = 0;
|
|
|
|
if (unlikely(!ti)) {
|
|
int srcu_idx;
|
|
struct dm_table *map = dm_get_live_table(md, &srcu_idx);
|
|
|
|
if (unlikely(!map)) {
|
|
dm_put_live_table(md, srcu_idx);
|
|
return;
|
|
}
|
|
ti = dm_table_find_target(map, pos);
|
|
dm_put_live_table(md, srcu_idx);
|
|
}
|
|
|
|
/*
|
|
* For suspend, check blk_queue_stopped() and increment
|
|
* ->pending within a single queue_lock not to increment the
|
|
* number of in-flight I/Os after the queue is stopped in
|
|
* dm_suspend().
|
|
*/
|
|
while (!blk_queue_stopped(q)) {
|
|
rq = blk_peek_request(q);
|
|
if (!rq)
|
|
return;
|
|
|
|
/* always use block 0 to find the target for flushes for now */
|
|
pos = 0;
|
|
if (req_op(rq) != REQ_OP_FLUSH)
|
|
pos = blk_rq_pos(rq);
|
|
|
|
if ((dm_old_request_peeked_before_merge_deadline(md) &&
|
|
md_in_flight(md) && rq->bio && !bio_multiple_segments(rq->bio) &&
|
|
md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) ||
|
|
(ti->type->busy && ti->type->busy(ti))) {
|
|
blk_delay_queue(q, 10);
|
|
return;
|
|
}
|
|
|
|
dm_start_request(md, rq);
|
|
|
|
tio = tio_from_request(rq);
|
|
init_tio(tio, rq, md);
|
|
/* Establish tio->ti before queuing work (map_tio_request) */
|
|
tio->ti = ti;
|
|
kthread_queue_work(&md->kworker, &tio->work);
|
|
BUG_ON(!irqs_disabled());
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Fully initialize a .request_fn request-based queue.
|
|
*/
|
|
int dm_old_init_request_queue(struct mapped_device *md, struct dm_table *t)
|
|
{
|
|
struct dm_target *immutable_tgt;
|
|
|
|
/* Fully initialize the queue */
|
|
md->queue->cmd_size = sizeof(struct dm_rq_target_io);
|
|
md->queue->rq_alloc_data = md;
|
|
md->queue->request_fn = dm_old_request_fn;
|
|
md->queue->init_rq_fn = dm_rq_init_rq;
|
|
|
|
immutable_tgt = dm_table_get_immutable_target(t);
|
|
if (immutable_tgt && immutable_tgt->per_io_data_size) {
|
|
/* any target-specific per-io data is immediately after the tio */
|
|
md->queue->cmd_size += immutable_tgt->per_io_data_size;
|
|
md->init_tio_pdu = true;
|
|
}
|
|
if (blk_init_allocated_queue(md->queue) < 0)
|
|
return -EINVAL;
|
|
|
|
/* disable dm_old_request_fn's merge heuristic by default */
|
|
md->seq_rq_merge_deadline_usecs = 0;
|
|
|
|
dm_init_normal_md_queue(md);
|
|
blk_queue_softirq_done(md->queue, dm_softirq_done);
|
|
|
|
/* Initialize the request-based DM worker thread */
|
|
kthread_init_worker(&md->kworker);
|
|
md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker,
|
|
"kdmwork-%s", dm_device_name(md));
|
|
if (IS_ERR(md->kworker_task)) {
|
|
int error = PTR_ERR(md->kworker_task);
|
|
md->kworker_task = NULL;
|
|
return error;
|
|
}
|
|
|
|
elv_register_queue(md->queue);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dm_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
|
|
unsigned int hctx_idx, unsigned int numa_node)
|
|
{
|
|
return __dm_rq_init_rq(set->driver_data, rq);
|
|
}
|
|
|
|
static blk_status_t dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
|
|
const struct blk_mq_queue_data *bd)
|
|
{
|
|
struct request *rq = bd->rq;
|
|
struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
|
|
struct mapped_device *md = tio->md;
|
|
struct dm_target *ti = md->immutable_target;
|
|
|
|
if (unlikely(!ti)) {
|
|
int srcu_idx;
|
|
struct dm_table *map = dm_get_live_table(md, &srcu_idx);
|
|
|
|
ti = dm_table_find_target(map, 0);
|
|
dm_put_live_table(md, srcu_idx);
|
|
}
|
|
|
|
if (ti->type->busy && ti->type->busy(ti))
|
|
return BLK_STS_RESOURCE;
|
|
|
|
dm_start_request(md, rq);
|
|
|
|
/* Init tio using md established in .init_request */
|
|
init_tio(tio, rq, md);
|
|
|
|
/*
|
|
* Establish tio->ti before calling map_request().
|
|
*/
|
|
tio->ti = ti;
|
|
|
|
/* Direct call is fine since .queue_rq allows allocations */
|
|
if (map_request(tio) == DM_MAPIO_REQUEUE) {
|
|
/* Undo dm_start_request() before requeuing */
|
|
rq_end_stats(md, rq);
|
|
rq_completed(md, rq_data_dir(rq), false);
|
|
blk_mq_delay_run_hw_queue(hctx, 100/*ms*/);
|
|
return BLK_STS_RESOURCE;
|
|
}
|
|
|
|
return BLK_STS_OK;
|
|
}
|
|
|
|
static const struct blk_mq_ops dm_mq_ops = {
|
|
.queue_rq = dm_mq_queue_rq,
|
|
.complete = dm_softirq_done,
|
|
.init_request = dm_mq_init_request,
|
|
};
|
|
|
|
int dm_mq_init_request_queue(struct mapped_device *md, struct dm_table *t)
|
|
{
|
|
struct request_queue *q;
|
|
struct dm_target *immutable_tgt;
|
|
int err;
|
|
|
|
if (!dm_table_all_blk_mq_devices(t)) {
|
|
DMERR("request-based dm-mq may only be stacked on blk-mq device(s)");
|
|
return -EINVAL;
|
|
}
|
|
|
|
md->tag_set = kzalloc_node(sizeof(struct blk_mq_tag_set), GFP_KERNEL, md->numa_node_id);
|
|
if (!md->tag_set)
|
|
return -ENOMEM;
|
|
|
|
md->tag_set->ops = &dm_mq_ops;
|
|
md->tag_set->queue_depth = dm_get_blk_mq_queue_depth();
|
|
md->tag_set->numa_node = md->numa_node_id;
|
|
md->tag_set->flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE;
|
|
md->tag_set->nr_hw_queues = dm_get_blk_mq_nr_hw_queues();
|
|
md->tag_set->driver_data = md;
|
|
|
|
md->tag_set->cmd_size = sizeof(struct dm_rq_target_io);
|
|
immutable_tgt = dm_table_get_immutable_target(t);
|
|
if (immutable_tgt && immutable_tgt->per_io_data_size) {
|
|
/* any target-specific per-io data is immediately after the tio */
|
|
md->tag_set->cmd_size += immutable_tgt->per_io_data_size;
|
|
md->init_tio_pdu = true;
|
|
}
|
|
|
|
err = blk_mq_alloc_tag_set(md->tag_set);
|
|
if (err)
|
|
goto out_kfree_tag_set;
|
|
|
|
q = blk_mq_init_allocated_queue(md->tag_set, md->queue);
|
|
if (IS_ERR(q)) {
|
|
err = PTR_ERR(q);
|
|
goto out_tag_set;
|
|
}
|
|
dm_init_md_queue(md);
|
|
|
|
/* backfill 'mq' sysfs registration normally done in blk_register_queue */
|
|
err = blk_mq_register_dev(disk_to_dev(md->disk), q);
|
|
if (err)
|
|
goto out_cleanup_queue;
|
|
|
|
return 0;
|
|
|
|
out_cleanup_queue:
|
|
blk_cleanup_queue(q);
|
|
out_tag_set:
|
|
blk_mq_free_tag_set(md->tag_set);
|
|
out_kfree_tag_set:
|
|
kfree(md->tag_set);
|
|
|
|
return err;
|
|
}
|
|
|
|
void dm_mq_cleanup_mapped_device(struct mapped_device *md)
|
|
{
|
|
if (md->tag_set) {
|
|
blk_mq_free_tag_set(md->tag_set);
|
|
kfree(md->tag_set);
|
|
}
|
|
}
|
|
|
|
module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR);
|
|
MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools");
|
|
|
|
module_param(use_blk_mq, bool, S_IRUGO | S_IWUSR);
|
|
MODULE_PARM_DESC(use_blk_mq, "Use block multiqueue for request-based DM devices");
|
|
|
|
module_param(dm_mq_nr_hw_queues, uint, S_IRUGO | S_IWUSR);
|
|
MODULE_PARM_DESC(dm_mq_nr_hw_queues, "Number of hardware queues for request-based dm-mq devices");
|
|
|
|
module_param(dm_mq_queue_depth, uint, S_IRUGO | S_IWUSR);
|
|
MODULE_PARM_DESC(dm_mq_queue_depth, "Queue depth for request-based dm-mq devices");
|