diff options
Diffstat (limited to 'drivers/md/dm.c')
| -rw-r--r-- | drivers/md/dm.c | 1110 |
1 files changed, 13 insertions, 1097 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index aba7ed9abb3a..8f22527134e9 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -5,13 +5,13 @@ * This file is released under the GPL. */ -#include "dm.h" +#include "dm-core.h" +#include "dm-rq.h" #include "dm-uevent.h" #include <linux/init.h> #include <linux/module.h> #include <linux/mutex.h> -#include <linux/moduleparam.h> #include <linux/blkpg.h> #include <linux/bio.h> #include <linux/mempool.h> @@ -20,14 +20,8 @@ #include <linux/hdreg.h> #include <linux/delay.h> #include <linux/wait.h> -#include <linux/kthread.h> -#include <linux/ktime.h> -#include <linux/elevator.h> /* for rq_end_sector() */ -#include <linux/blk-mq.h> #include <linux/pr.h> -#include <trace/events/block.h> - #define DM_MSG_PREFIX "core" #ifdef CONFIG_PRINTK @@ -63,7 +57,6 @@ static DECLARE_WORK(deferred_remove_work, do_deferred_remove); static struct workqueue_struct *deferred_remove_workqueue; /* - * For bio-based dm. * One of these is allocated per bio. */ struct dm_io { @@ -76,36 +69,6 @@ struct dm_io { struct dm_stats_aux stats_aux; }; -/* - * For request-based dm. - * One of these is allocated per request. - */ -struct dm_rq_target_io { - struct mapped_device *md; - struct dm_target *ti; - struct request *orig, *clone; - struct kthread_work work; - int error; - union map_info info; - struct dm_stats_aux stats_aux; - unsigned long duration_jiffies; - unsigned n_sectors; -}; - -/* - * For request-based dm - the bio clones we allocate are embedded in these - * structs. - * - * We allocate these with bio_alloc_bioset, using the front_pad parameter when - * the bioset is created - this means the bio has to come at the end of the - * struct. - */ -struct dm_rq_clone_bio_info { - struct bio *orig; - struct dm_rq_target_io *tio; - struct bio clone; -}; - #define MINOR_ALLOCED ((void *)-1) /* @@ -120,130 +83,9 @@ struct dm_rq_clone_bio_info { #define DMF_DEFERRED_REMOVE 6 #define DMF_SUSPENDED_INTERNALLY 7 -/* - * Work processed by per-device workqueue. - */ -struct mapped_device { - struct srcu_struct io_barrier; - struct mutex suspend_lock; - - /* - * The current mapping (struct dm_table *). - * Use dm_get_live_table{_fast} or take suspend_lock for - * dereference. - */ - void __rcu *map; - - struct list_head table_devices; - struct mutex table_devices_lock; - - unsigned long flags; - - struct request_queue *queue; - int numa_node_id; - - unsigned type; - /* Protect queue and type against concurrent access. */ - struct mutex type_lock; - - atomic_t holders; - atomic_t open_count; - - struct dm_target *immutable_target; - struct target_type *immutable_target_type; - - struct gendisk *disk; - char name[16]; - - void *interface_ptr; - - /* - * A list of ios that arrived while we were suspended. - */ - atomic_t pending[2]; - wait_queue_head_t wait; - struct work_struct work; - spinlock_t deferred_lock; - struct bio_list deferred; - - /* - * Event handling. - */ - wait_queue_head_t eventq; - atomic_t event_nr; - atomic_t uevent_seq; - struct list_head uevent_list; - spinlock_t uevent_lock; /* Protect access to uevent_list */ - - /* the number of internal suspends */ - unsigned internal_suspend_count; - - /* - * Processing queue (flush) - */ - struct workqueue_struct *wq; - - /* - * io objects are allocated from here. - */ - mempool_t *io_pool; - mempool_t *rq_pool; - - struct bio_set *bs; - - /* - * freeze/thaw support require holding onto a super block - */ - struct super_block *frozen_sb; - - /* forced geometry settings */ - struct hd_geometry geometry; - - struct block_device *bdev; - - /* kobject and completion */ - struct dm_kobject_holder kobj_holder; - - /* zero-length flush that will be cloned and submitted to targets */ - struct bio flush_bio; - - struct dm_stats stats; - - struct kthread_worker kworker; - struct task_struct *kworker_task; - - /* for request-based merge heuristic in dm_request_fn() */ - unsigned seq_rq_merge_deadline_usecs; - int last_rq_rw; - sector_t last_rq_pos; - ktime_t last_rq_start_time; - - /* for blk-mq request-based DM support */ - struct blk_mq_tag_set *tag_set; - bool use_blk_mq:1; - bool init_tio_pdu:1; -}; - -#ifdef CONFIG_DM_MQ_DEFAULT -static bool use_blk_mq = true; -#else -static bool use_blk_mq = false; -#endif - -#define DM_MQ_NR_HW_QUEUES 1 -#define DM_MQ_QUEUE_DEPTH 2048 #define DM_NUMA_NODE NUMA_NO_NODE - -static unsigned dm_mq_nr_hw_queues = DM_MQ_NR_HW_QUEUES; -static unsigned dm_mq_queue_depth = DM_MQ_QUEUE_DEPTH; static int dm_numa_node = DM_NUMA_NODE; -bool dm_use_blk_mq(struct mapped_device *md) -{ - return md->use_blk_mq; -} -EXPORT_SYMBOL_GPL(dm_use_blk_mq); - /* * For mempools pre-allocation at the table loading time. */ @@ -259,9 +101,6 @@ struct table_device { struct dm_dev dm_dev; }; -#define RESERVED_BIO_BASED_IOS 16 -#define RESERVED_REQUEST_BASED_IOS 256 -#define RESERVED_MAX_IOS 1024 static struct kmem_cache *_io_cache; static struct kmem_cache *_rq_tio_cache; static struct kmem_cache *_rq_cache; @@ -269,13 +108,9 @@ static struct kmem_cache *_rq_cache; /* * Bio-based DM's mempools' reserved IOs set by the user. */ +#define RESERVED_BIO_BASED_IOS 16 static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS; -/* - * Request-based DM's mempools' reserved IOs set by the user. - */ -static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS; - static int __dm_get_module_param_int(int *module_param, int min, int max) { int param = ACCESS_ONCE(*module_param); @@ -297,8 +132,8 @@ static int __dm_get_module_param_int(int *module_param, int min, int max) return param; } -static unsigned __dm_get_module_param(unsigned *module_param, - unsigned def, unsigned max) +unsigned __dm_get_module_param(unsigned *module_param, + unsigned def, unsigned max) { unsigned param = ACCESS_ONCE(*module_param); unsigned modified_param = 0; @@ -319,28 +154,10 @@ static unsigned __dm_get_module_param(unsigned *module_param, unsigned dm_get_reserved_bio_based_ios(void) { return __dm_get_module_param(&reserved_bio_based_ios, - RESERVED_BIO_BASED_IOS, RESERVED_MAX_IOS); + RESERVED_BIO_BASED_IOS, DM_RESERVED_MAX_IOS); } EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios); -unsigned dm_get_reserved_rq_based_ios(void) -{ - return __dm_get_module_param(&reserved_rq_based_ios, - RESERVED_REQUEST_BASED_IOS, RESERVED_MAX_IOS); -} -EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios); - -static unsigned dm_get_blk_mq_nr_hw_queues(void) -{ - return __dm_get_module_param(&dm_mq_nr_hw_queues, 1, 32); -} - -static unsigned dm_get_blk_mq_queue_depth(void) -{ - return __dm_get_module_param(&dm_mq_queue_depth, - DM_MQ_QUEUE_DEPTH, BLK_MQ_MAX_DEPTH); -} - static unsigned dm_get_numa_node(void) { return __dm_get_module_param_int(&dm_numa_node, @@ -679,29 +496,7 @@ static void free_tio(struct dm_target_io *tio) bio_put(&tio->clone); } -static struct dm_rq_target_io *alloc_old_rq_tio(struct mapped_device *md, - gfp_t gfp_mask) -{ - return mempool_alloc(md->io_pool, gfp_mask); -} - -static void free_old_rq_tio(struct dm_rq_target_io *tio) -{ - mempool_free(tio, tio->md->io_pool); -} - -static struct request *alloc_old_clone_request(struct mapped_device *md, - gfp_t gfp_mask) -{ - return mempool_alloc(md->rq_pool, gfp_mask); -} - -static void free_old_clone_request(struct mapped_device *md, struct request *rq) -{ - mempool_free(rq, md->rq_pool); -} - -static int md_in_flight(struct mapped_device *md) +int md_in_flight(struct mapped_device *md) { return atomic_read(&md->pending[READ]) + atomic_read(&md->pending[WRITE]); @@ -1019,7 +814,7 @@ static void dec_pending(struct dm_io *io, int error) } } -static void disable_write_same(struct mapped_device *md) +void disable_write_same(struct mapped_device *md) { struct queue_limits *limits = dm_get_queue_limits(md); @@ -1062,371 +857,6 @@ static void clone_endio(struct bio *bio) } /* - * Partial completion handling for request-based dm - */ -static void end_clone_bio(struct bio *clone) -{ - struct dm_rq_clone_bio_info *info = - container_of(clone, struct dm_rq_clone_bio_info, clone); - struct dm_rq_target_io *tio = info->tio; - struct bio *bio = info->orig; - unsigned int nr_bytes = info->orig->bi_iter.bi_size; - int error = clone->bi_error; - - bio_put(clone); - - if (tio->error) - /* - * An error has already been detected on the request. - * Once error occurred, just let clone->end_io() handle - * the remainder. - */ - return; - else if (error) { - /* - * Don't notice the error to the upper layer yet. - * The error handling decision is made by the target driver, - * when the request is completed. - */ - tio->error = error; - return; - } - - /* - * I/O for the bio successfully completed. - * Notice the data completion to the upper layer. - */ - - /* - * bios are processed from the head of the list. - * So the completing bio should always be rq->bio. - * If it's not, something wrong is happening. - */ - if (tio->orig->bio != bio) - DMERR("bio completion is going in the middle of the request"); - - /* - * Update the original request. - * Do not use blk_end_request() here, because it may complete - * the original request before the clone, and break the ordering. - */ - blk_update_request(tio->orig, 0, nr_bytes); -} - -static struct dm_rq_target_io *tio_from_request(struct request *rq) -{ - return (rq->q->mq_ops ? blk_mq_rq_to_pdu(rq) : rq->special); -} - -static void rq_end_stats(struct mapped_device *md, struct request *orig) -{ - if (unlikely(dm_stats_used(&md->stats))) { - struct dm_rq_target_io *tio = tio_from_request(orig); - tio->duration_jiffies = jiffies - tio->duration_jiffies; - dm_stats_account_io(&md->stats, rq_data_dir(orig), - blk_rq_pos(orig), tio->n_sectors, true, - tio->duration_jiffies, &tio->stats_aux); - } -} - -/* - * Don't touch any member of the md after calling this function because - * the md may be freed in dm_put() at the end of this function. - * Or do dm_get() before calling this function and dm_put() later. - */ -static void rq_completed(struct mapped_device *md, int rw, bool run_queue) -{ - atomic_dec(&md->pending[rw]); - - /* nudge anyone waiting on suspend queue */ - if (!md_in_flight(md)) - wake_up(&md->wait); - - /* - * Run this off this callpath, as drivers could invoke end_io while - * inside their request_fn (and holding the queue lock). Calling - * back into ->request_fn() could deadlock attempting to grab the - * queue lock again. - */ - if (!md->queue->mq_ops && run_queue) - blk_run_queue_async(md->queue); - - /* - * dm_put() must be at the end of this function. See the comment above - */ - dm_put(md); -} - -static void free_rq_clone(struct request *clone) -{ - struct dm_rq_target_io *tio = clone->end_io_data; - struct mapped_device *md = tio->md; - - blk_rq_unprep_clone(clone); - - if (md->type == DM_TYPE_MQ_REQUEST_BASED) - /* stacked on blk-mq queue(s) */ - tio->ti->type->release_clone_rq(clone); - else if (!md->queue->mq_ops) - /* request_fn queue stacked on request_fn queue(s) */ - free_old_clone_request(md, clone); - - if (!md->queue->mq_ops) - free_old_rq_tio(tio); -} - -/* - * Complete the clone and the original request. - * Must be called without clone's queue lock held, - * see end_clone_request() for more details. - */ -static void dm_end_request(struct request *clone, int error) -{ - int rw = rq_data_dir(clone); - struct dm_rq_target_io *tio = clone->end_io_data; - struct mapped_device *md = tio->md; - struct request *rq = tio->orig; - - if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { - rq->errors = clone->errors; - rq->resid_len = clone->resid_len; - - if (rq->sense) - /* - * We are using the sense buffer of the original - * request. - * So setting the length of the sense data is enough. - */ - rq->sense_len = clone->sense_len; - } - - free_rq_clone(clone); - rq_end_stats(md, rq); - if (!rq->q->mq_ops) - blk_end_request_all(rq, error); - else - blk_mq_end_request(rq, error); - rq_completed(md, rw, true); -} - -static void dm_unprep_request(struct request *rq) -{ - struct dm_rq_target_io *tio = tio_from_request(rq); - struct request *clone = tio->clone; - - if (!rq->q->mq_ops) { - rq->special = NULL; - rq->cmd_flags &= ~REQ_DONTPREP; - } - - if (clone) - free_rq_clone(clone); - else if (!tio->md->queue->mq_ops) - free_old_rq_tio(tio); -} - -/* - * Requeue the original request of a clone. - */ -static void dm_old_requeue_request(struct request *rq) -{ - struct request_queue *q = rq->q; - unsigned long flags; - - spin_lock_irqsave(q->queue_lock, flags); - blk_requeue_request(q, rq); - blk_run_queue_async(q); - spin_unlock_irqrestore(q->queue_lock, flags); -} - -static void dm_mq_requeue_request(struct request *rq) -{ - struct request_queue *q = rq->q; - unsigned long flags; - - blk_mq_requeue_request(rq); - spin_lock_irqsave(q->queue_lock, flags); - if (!blk_queue_stopped(q)) - blk_mq_kick_requeue_list(q); - spin_unlock_irqrestore(q->queue_lock, flags); -} - -static void dm_requeue_original_request(struct mapped_device *md, - struct request *rq) -{ - int rw = rq_data_dir(rq); - - rq_end_stats(md, rq); - dm_unprep_request(rq); - - if (!rq->q->mq_ops) - dm_old_requeue_request(rq); - else - dm_mq_requeue_request(rq); - - rq_completed(md, rw, false); -} - -static void dm_old_stop_queue(struct request_queue *q) -{ - unsigned long flags; - - spin_lock_irqsave(q->queue_lock, flags); - if (blk_queue_stopped(q)) { - spin_unlock_irqrestore(q->queue_lock, flags); - return; - } - - blk_stop_queue(q); - spin_unlock_irqrestore(q->queue_lock, flags); -} - -static void dm_stop_queue(struct request_queue *q) -{ - if (!q->mq_ops) - dm_old_stop_queue(q); - else - blk_mq_stop_hw_queues(q); -} - -static void dm_old_start_queue(struct request_queue *q) -{ - unsigned long flags; - - spin_lock_irqsave(q->queue_lock, flags); - if (blk_queue_stopped(q)) - blk_start_queue(q); - spin_unlock_irqrestore(q->queue_lock, flags); -} - -static void dm_start_queue(struct request_queue *q) -{ - if (!q->mq_ops) - dm_old_start_queue(q); - else { - blk_mq_start_stopped_hw_queues(q, true); - blk_mq_kick_requeue_list(q); - } -} - -static void dm_done(struct request *clone, int error, bool mapped) -{ - int r = error; - struct dm_rq_target_io *tio = clone->end_io_data; - dm_request_endio_fn rq_end_io = NULL; - - if (tio->ti) { - rq_end_io = tio->ti->type->rq_end_io; - - if (mapped && rq_end_io) - r = rq_end_io(tio->ti, clone, error, &tio->info); - } - - if (unlikely(r == -EREMOTEIO && (req_op(clone) == REQ_OP_WRITE_SAME) && - !clone->q->limits.max_write_same_sectors)) - disable_write_same(tio->md); - - if (r <= 0) - /* The target wants to complete the I/O */ - dm_end_request(clone, r); - else if (r == DM_ENDIO_INCOMPLETE) - /* The target will handle the I/O */ - return; - else if (r == DM_ENDIO_REQUEUE) - /* The target wants to requeue the I/O */ - dm_requeue_original_request(tio->md, tio->orig); - else { - DMWARN("unimplemented target endio return value: %d", r); - BUG(); - } -} - -/* - * Request completion handler for request-based dm - */ -static void dm_softirq_done(struct request *rq) -{ - bool mapped = true; - struct dm_rq_target_io *tio = tio_from_request(rq); - struct request *clone = tio->clone; - int rw; - - if (!clone) { - rq_end_stats(tio->md, rq); - rw = rq_data_dir(rq); - if (!rq->q->mq_ops) { - blk_end_request_all(rq, tio->error); - rq_completed(tio->md, rw, false); - free_old_rq_tio(tio); - } else { - blk_mq_end_request(rq, tio->error); - rq_completed(tio->md, rw, false); - } - return; - } - - if (rq->cmd_flags & REQ_FAILED) - mapped = false; - - dm_done(clone, tio->error, mapped); -} - -/* - * Complete the clone and the original request with the error status - * through softirq context. - */ -static void dm_complete_request(struct request *rq, int error) -{ - struct dm_rq_target_io *tio = tio_from_request(rq); - - tio->error = error; - if (!rq->q->mq_ops) - blk_complete_request(rq); - else - blk_mq_complete_request(rq, error); -} - -/* - * Complete the not-mapped clone and the original request with the error status - * through softirq context. - * Target's rq_end_io() function isn't called. - * This may be used when the target's map_rq() or clone_and_map_rq() functions fail. - */ -static void dm_kill_unmapped_request(struct request *rq, int error) -{ - rq->cmd_flags |= REQ_FAILED; - dm_complete_request(rq, error); -} - -/* - * Called with the clone's queue lock held (in the case of .request_fn) - */ -static void end_clone_request(struct request *clone, int error) -{ - struct dm_rq_target_io *tio = clone->end_io_data; - - if (!clone->q->mq_ops) { - /* - * For just cleaning up the information of the queue in which - * the clone was dispatched. - * The clone is *NOT* freed actually here because it is alloced - * from dm own mempool (REQ_ALLOCED isn't set). - */ - __blk_put_request(clone->q, clone); - } - - /* - * Actual request completion is done in a softirq context which doesn't - * hold the clone's queue lock. Otherwise, deadlock could occur because: - * - another request may be submitted by the upper level driver - * of the stacking during the completion - * - the submission which requires queue lock may be done - * against this clone's queue - */ - dm_complete_request(tio->orig, error); -} - -/* * Return maximum size of I/O possible at the supplied sector up to the current * target boundary. */ @@ -1845,353 +1275,6 @@ static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio) return BLK_QC_T_NONE; } -int dm_request_based(struct mapped_device *md) -{ - return blk_queue_stackable(md->queue); -} - -static void dm_dispatch_clone_request(struct request *clone, struct request *rq) -{ - int r; - - if (blk_queue_io_stat(clone->q)) - clone->cmd_flags |= REQ_IO_STAT; - - clone->start_time = jiffies; - r = blk_insert_cloned_request(clone->q, clone); - if (r) - /* must complete clone in terms of original request */ - dm_complete_request(rq, r); -} - -static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig, - void *data) -{ - struct dm_rq_target_io *tio = data; - struct dm_rq_clone_bio_info *info = - container_of(bio, struct dm_rq_clone_bio_info, clone); - - info->orig = bio_orig; - info->tio = tio; - bio->bi_end_io = end_clone_bio; - - return 0; -} - -static int setup_clone(struct request *clone, struct request *rq, - struct dm_rq_target_io *tio, gfp_t gfp_mask) -{ - int r; - - r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask, - dm_rq_bio_constructor, tio); - if (r) - return r; - - clone->cmd = rq->cmd; - clone->cmd_len = rq->cmd_len; - clone->sense = rq->sense; - clone->end_io = end_clone_request; - clone->end_io_data = tio; - - tio->clone = clone; - - return 0; -} - -static struct request *clone_old_rq(struct request *rq, struct mapped_device *md, - struct dm_rq_target_io *tio, gfp_t gfp_mask) -{ - /* - * Create clone for use with .request_fn request_queue - */ - struct request *clone; - - clone = alloc_old_clone_request(md, gfp_mask); - if (!clone) - return NULL; - - blk_rq_init(NULL, clone); - if (setup_clone(clone, rq, tio, gfp_mask)) { - /* -ENOMEM */ - free_old_clone_request(md, clone); - return NULL; - } - - return clone; -} - -static void map_tio_request(struct kthread_work *work); - -static void init_tio(struct dm_rq_target_io *tio, struct request *rq, - struct mapped_device *md) -{ - tio->md = md; - tio->ti = NULL; - tio->clone = NULL; - tio->orig = rq; - tio->error = 0; - /* - * Avoid initializing info for blk-mq; it passes - * target-specific data through info.ptr - * (see: dm_mq_init_request) - */ - if (!md->init_tio_pdu) - memset(&tio->info, 0, sizeof(tio->info)); - if (md->kworker_task) - init_kthread_work(&tio->work, map_tio_request); -} - -static struct dm_rq_target_io *dm_old_prep_tio(struct request *rq, - struct mapped_device *md, - gfp_t gfp_mask) -{ - struct dm_rq_target_io *tio; - int srcu_idx; - struct dm_table *table; - - tio = alloc_old_rq_tio(md, gfp_mask); - if (!tio) - return NULL; - - init_tio(tio, rq, md); - - table = dm_get_live_table(md, &srcu_idx); - /* - * Must clone a request if this .request_fn DM device - * is stacked on .request_fn device(s). - */ - if (!dm_table_mq_request_based(table)) { - if (!clone_old_rq(rq, md, tio, gfp_mask)) { - dm_put_live_table(md, srcu_idx); - free_old_rq_tio(tio); - return NULL; - } - } - dm_put_live_table(md, srcu_idx); - - return tio; -} - -/* - * Called with the queue lock held. - */ -static int dm_old_prep_fn(struct request_queue *q, struct request *rq) -{ - struct mapped_device *md = q->queuedata; - struct dm_rq_target_io *tio; - - if (unlikely(rq->special)) { - DMWARN("Already has something in rq->special."); - return BLKPREP_KILL; - } - - tio = dm_old_prep_tio(rq, md, GFP_ATOMIC); - if (!tio) - return BLKPREP_DEFER; - - rq->special = tio; - rq->cmd_flags |= REQ_DONTPREP; - - return BLKPREP_OK; -} - -/* - * Returns: - * 0 : the request has been processed - * DM_MAPIO_REQUEUE : the original request needs to be requeued - * < 0 : the request was completed due to failure - */ -static int map_request(struct dm_rq_target_io *tio, struct request *rq, - struct mapped_device *md) -{ - int r; - struct dm_target *ti = tio->ti; - struct request *clone = NULL; - - if (tio->clone) { - clone = tio->clone; - r = ti->type->map_rq(ti, clone, &tio->info); - } else { - r = ti->type->clone_and_map_rq(ti, rq, &tio->info, &clone); - if (r < 0) { - /* The target wants to complete the I/O */ - dm_kill_unmapped_request(rq, r); - return r; - } - if (r != DM_MAPIO_REMAPPED) - return r; - if (setup_clone(clone, rq, tio, GFP_ATOMIC)) { - /* -ENOMEM */ - ti->type->release_clone_rq(clone); - return DM_MAPIO_REQUEUE; - } - } - - switch (r) { - case DM_MAPIO_SUBMITTED: - /* The target has taken the I/O to submit by itself later */ - break; - case DM_MAPIO_REMAPPED: - /* The target has remapped the I/O so dispatch it */ - trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)), - blk_rq_pos(rq)); - dm_dispatch_clone_request(clone, rq); - break; - case DM_MAPIO_REQUEUE: - /* The target wants to requeue the I/O */ - dm_requeue_original_request(md, tio->orig); - break; - default: - if (r > 0) { - DMWARN("unimplemented target map return value: %d", r); - BUG(); - } - - /* The target wants to complete the I/O */ - dm_kill_unmapped_request(rq, r); - return r; - } - - return 0; -} - -static void map_tio_request(struct kthread_work *work) -{ - struct dm_rq_target_io *tio = container_of(work, struct dm_rq_target_io, work); - struct request *rq = tio->orig; - struct mapped_device *md = tio->md; - - if (map_request(tio, rq, md) == DM_MAPIO_REQUEUE) - dm_requeue_original_request(md, rq); -} - -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); -} - -#define MAX_SEQ_RQ_MERGE_DEADLINE_USECS 100000 - -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); -} - -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_request_based(md) || md->use_blk_mq) - 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_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 request-based dm. - * Called with the queue lock held. - */ -static void dm_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); - - 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_request_peeked_before_merge_deadline(md) && - md_in_flight(md) && rq->bio && rq->bio->bi_vcnt == 1 && - md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) || - (ti->type->busy && ti->type->busy(ti))) { - blk_delay_queue(q, HZ / 100); - return; - } - - dm_start_request(md, rq); - - tio = tio_from_request(rq); - /* Establish tio->ti before queuing work (map_tio_request) */ - tio->ti = ti; - queue_kthread_work(&md->kworker, &tio->work); - BUG_ON(!irqs_disabled()); - } -} - static int dm_any_congested(void *congested_data, int bdi_bits) { int r = bdi_bits; @@ -2269,7 +1352,7 @@ static const struct block_device_operations dm_blk_dops; static void dm_wq_work(struct work_struct *work); -static void dm_init_md_queue(struct mapped_device *md) +void dm_init_md_queue(struct mapped_device *md) { /* * Request-based dm devices cannot be stacked on top of bio-based dm @@ -2290,7 +1373,7 @@ static void dm_init_md_queue(struct mapped_device *md) md->queue->backing_dev_info.congested_data = md; } -static void dm_init_normal_md_queue(struct mapped_device *md) +void dm_init_normal_md_queue(struct mapped_device *md) { md->use_blk_mq = false; dm_init_md_queue(md); @@ -2330,6 +1413,8 @@ static void cleanup_mapped_device(struct mapped_device *md) bdput(md->bdev); md->bdev = NULL; } + + dm_mq_cleanup_mapped_device(md); } /* @@ -2363,7 +1448,7 @@ static struct mapped_device *alloc_dev(int minor) goto bad_io_barrier; md->numa_node_id = numa_node_id; - md->use_blk_mq = use_blk_mq; + md->use_blk_mq = dm_use_blk_mq_default(); md->init_tio_pdu = false; md->type = DM_TYPE_NONE; mutex_init(&md->suspend_lock); @@ -2448,10 +1533,6 @@ static void free_dev(struct mapped_device *md) unlock_fs(md); cleanup_mapped_device(md); - if (md->tag_set) { - blk_mq_free_tag_set(md->tag_set); - kfree(md->tag_set); - } free_table_devices(&md->table_devices); dm_stats_cleanup(&md->stats); @@ -2657,159 +1738,6 @@ struct queue_limits *dm_get_queue_limits(struct mapped_device *md) } EXPORT_SYMBOL_GPL(dm_get_queue_limits); -static void dm_old_init_rq_based_worker_thread(struct mapped_device *md) -{ - /* Initialize the request-based DM worker thread */ - init_kthread_worker(&md->kworker); - md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker, - "kdmwork-%s", dm_device_name(md)); -} - -/* - * Fully initialize a .request_fn request-based queue. - */ -static int dm_old_init_request_queue(struct mapped_device *md) -{ - /* Fully initialize the queue */ - if (!blk_init_allocated_queue(md->queue, dm_request_fn, NULL)) - return -EINVAL; - - /* disable dm_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); - blk_queue_prep_rq(md->queue, dm_old_prep_fn); - - dm_old_init_rq_based_worker_thread(md); - - elv_register_queue(md->queue); - - return 0; -} - -static int dm_mq_init_request(void *data, struct request *rq, - unsigned int hctx_idx, unsigned int request_idx, - unsigned int numa_node) -{ - struct mapped_device *md = data; - 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_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_MQ_RQ_QUEUE_BUSY; - - dm_start_request(md, rq); - - /* Init tio using md established in .init_request */ - init_tio(tio, rq, md); - - /* - * Establish tio->ti before queuing work (map_tio_request) - * or making direct call to map_request(). - */ - tio->ti = ti; - - /* Direct call is fine since .queue_rq allows allocations */ - if (map_request(tio, rq, md) == DM_MAPIO_REQUEUE) { - /* Undo dm_start_request() before requeuing */ - rq_end_stats(md, rq); - rq_completed(md, rq_data_dir(rq), false); - return BLK_MQ_RQ_QUEUE_BUSY; - } - - return BLK_MQ_RQ_QUEUE_OK; -} - -static struct blk_mq_ops dm_mq_ops = { - .queue_rq = dm_mq_queue_rq, - .map_queue = blk_mq_map_queue, - .complete = dm_softirq_done, - .init_request = dm_mq_init_request, -}; - -static int dm_mq_init_request_queue(struct mapped_device *md, - struct dm_target *immutable_tgt) -{ - struct request_queue *q; - int err; - - if (dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) { - 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); - 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 */ - blk_mq_register_disk(md->disk); - - return 0; - -out_tag_set: - blk_mq_free_tag_set(md->tag_set); -out_kfree_tag_set: - kfree(md->tag_set); - - return err; -} - static unsigned filter_md_type(unsigned type, struct mapped_device *md) { if (type == DM_TYPE_BIO_BASED) @@ -3741,18 +2669,6 @@ MODULE_PARM_DESC(major, "The major number of the device mapper"); module_param(reserved_bio_based_ios, uint, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools"); -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"); - module_param(dm_numa_node, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(dm_numa_node, "NUMA node for DM device memory allocations"); |
