#include <linux/hdreg.h>
#include <linux/delay.h>
#include <linux/wait.h>
+#include <linux/kthread.h>
#include <trace/events/block.h>
struct dm_rq_target_io {
struct mapped_device *md;
struct dm_target *ti;
- struct request *orig, clone;
+ struct request *orig, *clone;
+ struct kthread_work work;
int error;
union map_info info;
};
* io objects are allocated from here.
*/
mempool_t *io_pool;
+ mempool_t *rq_pool;
struct bio_set *bs;
unsigned internal_suspend_count;
struct dm_stats stats;
+
+ struct kthread_worker kworker;
+ struct task_struct *kworker_task;
};
/*
*/
struct dm_md_mempools {
mempool_t *io_pool;
+ mempool_t *rq_pool;
struct bio_set *bs;
};
#define RESERVED_MAX_IOS 1024
static struct kmem_cache *_io_cache;
static struct kmem_cache *_rq_tio_cache;
+static struct kmem_cache *_rq_cache;
/*
* Bio-based DM's mempools' reserved IOs set by the user.
if (!_rq_tio_cache)
goto out_free_io_cache;
+ _rq_cache = kmem_cache_create("dm_clone_request", sizeof(struct request),
+ __alignof__(struct request), 0, NULL);
+ if (!_rq_cache)
+ goto out_free_rq_tio_cache;
+
r = dm_uevent_init();
if (r)
- goto out_free_rq_tio_cache;
+ goto out_free_rq_cache;
deferred_remove_workqueue = alloc_workqueue("kdmremove", WQ_UNBOUND, 1);
if (!deferred_remove_workqueue) {
destroy_workqueue(deferred_remove_workqueue);
out_uevent_exit:
dm_uevent_exit();
+out_free_rq_cache:
+ kmem_cache_destroy(_rq_cache);
out_free_rq_tio_cache:
kmem_cache_destroy(_rq_tio_cache);
out_free_io_cache:
flush_scheduled_work();
destroy_workqueue(deferred_remove_workqueue);
+ kmem_cache_destroy(_rq_cache);
kmem_cache_destroy(_rq_tio_cache);
kmem_cache_destroy(_io_cache);
unregister_blkdev(_major, _name);
mempool_free(tio, tio->md->io_pool);
}
+static struct request *alloc_clone_request(struct mapped_device *md,
+ gfp_t gfp_mask)
+{
+ return mempool_alloc(md->rq_pool, gfp_mask);
+}
+
+static void free_clone_request(struct mapped_device *md, struct request *rq)
+{
+ mempool_free(rq, md->rq_pool);
+}
+
static int md_in_flight(struct mapped_device *md)
{
return atomic_read(&md->pending[READ]) +
* 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, int run_queue)
+static void rq_completed(struct mapped_device *md, int rw, bool run_queue)
{
atomic_dec(&md->pending[rw]);
struct dm_rq_target_io *tio = clone->end_io_data;
blk_rq_unprep_clone(clone);
+ if (clone->q && clone->q->mq_ops)
+ tio->ti->type->release_clone_rq(clone);
+ else
+ free_clone_request(tio->md, clone);
free_rq_tio(tio);
}
/*
* Complete the clone and the original request.
- * Must be called without queue lock.
+ * 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)
{
static void dm_unprep_request(struct request *rq)
{
- struct request *clone = rq->special;
+ struct dm_rq_target_io *tio = rq->special;
+ struct request *clone = tio->clone;
rq->special = NULL;
rq->cmd_flags &= ~REQ_DONTPREP;
- free_rq_clone(clone);
+ if (clone)
+ free_rq_clone(clone);
}
/*
* Requeue the original request of a clone.
*/
-void dm_requeue_unmapped_request(struct request *clone)
+static void dm_requeue_unmapped_original_request(struct mapped_device *md,
+ struct request *rq)
{
- 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;
+ int rw = rq_data_dir(rq);
struct request_queue *q = rq->q;
unsigned long flags;
blk_requeue_request(q, rq);
spin_unlock_irqrestore(q->queue_lock, flags);
- rq_completed(md, rw, 0);
+ rq_completed(md, rw, false);
+}
+
+static void dm_requeue_unmapped_request(struct request *clone)
+{
+ struct dm_rq_target_io *tio = clone->end_io_data;
+
+ dm_requeue_unmapped_original_request(tio->md, tio->orig);
}
-EXPORT_SYMBOL_GPL(dm_requeue_unmapped_request);
static void __stop_queue(struct request_queue *q)
{
static void dm_softirq_done(struct request *rq)
{
bool mapped = true;
- struct request *clone = rq->completion_data;
- struct dm_rq_target_io *tio = clone->end_io_data;
+ struct dm_rq_target_io *tio = rq->special;
+ struct request *clone = tio->clone;
+
+ if (!clone) {
+ blk_end_request_all(rq, tio->error);
+ rq_completed(tio->md, rq_data_dir(rq), false);
+ free_rq_tio(tio);
+ return;
+ }
if (rq->cmd_flags & REQ_FAILED)
mapped = false;
* Complete the clone and the original request with the error status
* through softirq context.
*/
-static void dm_complete_request(struct request *clone, int error)
+static void dm_complete_request(struct request *rq, int error)
{
- struct dm_rq_target_io *tio = clone->end_io_data;
- struct request *rq = tio->orig;
+ struct dm_rq_target_io *tio = rq->special;
tio->error = error;
- rq->completion_data = clone;
blk_complete_request(rq);
}
* 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() function fails.
+ * This may be used when the target's map_rq() or clone_and_map_rq() functions fail.
*/
-void dm_kill_unmapped_request(struct request *clone, int error)
+static void dm_kill_unmapped_request(struct request *rq, int error)
{
- struct dm_rq_target_io *tio = clone->end_io_data;
- struct request *rq = tio->orig;
-
rq->cmd_flags |= REQ_FAILED;
- dm_complete_request(clone, error);
+ dm_complete_request(rq, error);
}
-EXPORT_SYMBOL_GPL(dm_kill_unmapped_request);
/*
- * Called with the queue lock held
+ * Called with the clone's queue lock held
*/
static void end_clone_request(struct request *clone, int error)
{
- /*
- * 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 and REQ_ALLOCED isn't set in clone->cmd_flags.
- */
- __blk_put_request(clone->q, clone);
+ 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 queue lock. Otherwise, deadlock could occur because:
+ * 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 queue
+ * against this clone's queue
*/
- dm_complete_request(clone, error);
+ dm_complete_request(tio->orig, error);
}
/*
_dm_request(q, bio);
}
-void dm_dispatch_request(struct request *rq)
+static void dm_dispatch_clone_request(struct request *clone, struct request *rq)
{
int r;
- if (blk_queue_io_stat(rq->q))
- rq->cmd_flags |= REQ_IO_STAT;
+ if (blk_queue_io_stat(clone->q))
+ clone->cmd_flags |= REQ_IO_STAT;
- rq->start_time = jiffies;
- r = blk_insert_cloned_request(rq->q, rq);
+ 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);
}
-EXPORT_SYMBOL_GPL(dm_dispatch_request);
static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig,
void *data)
}
static int setup_clone(struct request *clone, struct request *rq,
- struct dm_rq_target_io *tio)
+ struct dm_rq_target_io *tio, gfp_t gfp_mask)
{
int r;
- blk_rq_init(NULL, clone);
- r = blk_rq_prep_clone(clone, rq, tio->md->bs, GFP_ATOMIC,
+ r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask,
dm_rq_bio_constructor, tio);
if (r)
return r;
clone->end_io = end_clone_request;
clone->end_io_data = tio;
+ tio->clone = clone;
+
return 0;
}
static struct request *clone_rq(struct request *rq, struct mapped_device *md,
- gfp_t gfp_mask)
+ struct dm_rq_target_io *tio, gfp_t gfp_mask)
+{
+ struct request *clone = alloc_clone_request(md, gfp_mask);
+
+ if (!clone)
+ return NULL;
+
+ blk_rq_init(NULL, clone);
+ if (setup_clone(clone, rq, tio, gfp_mask)) {
+ /* -ENOMEM */
+ free_clone_request(md, clone);
+ return NULL;
+ }
+
+ return clone;
+}
+
+static void map_tio_request(struct kthread_work *work);
+
+static struct dm_rq_target_io *prep_tio(struct request *rq,
+ struct mapped_device *md, gfp_t gfp_mask)
{
- struct request *clone;
struct dm_rq_target_io *tio;
+ int srcu_idx;
+ struct dm_table *table;
tio = alloc_rq_tio(md, gfp_mask);
if (!tio)
tio->md = md;
tio->ti = NULL;
+ tio->clone = NULL;
tio->orig = rq;
tio->error = 0;
memset(&tio->info, 0, sizeof(tio->info));
-
- clone = &tio->clone;
- if (setup_clone(clone, rq, tio)) {
- /* -ENOMEM */
- free_rq_tio(tio);
- return NULL;
+ init_kthread_work(&tio->work, map_tio_request);
+
+ table = dm_get_live_table(md, &srcu_idx);
+ if (!dm_table_mq_request_based(table)) {
+ if (!clone_rq(rq, md, tio, gfp_mask)) {
+ dm_put_live_table(md, srcu_idx);
+ free_rq_tio(tio);
+ return NULL;
+ }
}
+ dm_put_live_table(md, srcu_idx);
- return clone;
+ return tio;
}
/*
static int dm_prep_fn(struct request_queue *q, struct request *rq)
{
struct mapped_device *md = q->queuedata;
- struct request *clone;
+ struct dm_rq_target_io *tio;
if (unlikely(rq->special)) {
DMWARN("Already has something in rq->special.");
return BLKPREP_KILL;
}
- clone = clone_rq(rq, md, GFP_ATOMIC);
- if (!clone)
+ tio = prep_tio(rq, md, GFP_ATOMIC);
+ if (!tio)
return BLKPREP_DEFER;
- rq->special = clone;
+ rq->special = tio;
rq->cmd_flags |= REQ_DONTPREP;
return BLKPREP_OK;
/*
* Returns:
- * 0 : the request has been processed (not requeued)
- * !0 : the request has been requeued
+ * 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_target *ti, struct request *clone,
+static int map_request(struct dm_target *ti, struct request *rq,
struct mapped_device *md)
{
- int r, requeued = 0;
- struct dm_rq_target_io *tio = clone->end_io_data;
+ int r;
+ struct dm_rq_target_io *tio = rq->special;
+ 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 (IS_ERR(clone))
+ return DM_MAPIO_REQUEUE;
+ if (setup_clone(clone, rq, tio, GFP_KERNEL)) {
+ /* -ENOMEM */
+ ti->type->release_clone_rq(clone);
+ return DM_MAPIO_REQUEUE;
+ }
+ }
- tio->ti = ti;
- r = ti->type->map_rq(ti, clone, &tio->info);
switch (r) {
case DM_MAPIO_SUBMITTED:
/* The target has taken the I/O to submit by itself later */
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(tio->orig));
- dm_dispatch_request(clone);
+ 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_unmapped_request(clone);
- requeued = 1;
break;
default:
if (r > 0) {
}
/* The target wants to complete the I/O */
- dm_kill_unmapped_request(clone, r);
- break;
+ dm_kill_unmapped_request(rq, r);
+ return r;
}
- return requeued;
+ return 0;
}
-static struct request *dm_start_request(struct mapped_device *md, struct request *orig)
+static void map_tio_request(struct kthread_work *work)
{
- struct request *clone;
+ 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->ti, rq, md) == DM_MAPIO_REQUEUE)
+ dm_requeue_unmapped_original_request(md, rq);
+}
+
+static void dm_start_request(struct mapped_device *md, struct request *orig)
+{
blk_start_request(orig);
- clone = orig->special;
- atomic_inc(&md->pending[rq_data_dir(clone)]);
+ atomic_inc(&md->pending[rq_data_dir(orig)]);
/*
* Hold the md reference here for the in-flight I/O.
* See the comment in rq_completed() too.
*/
dm_get(md);
-
- return clone;
}
/*
int srcu_idx;
struct dm_table *map = dm_get_live_table(md, &srcu_idx);
struct dm_target *ti;
- struct request *rq, *clone;
+ struct request *rq;
+ struct dm_rq_target_io *tio;
sector_t pos;
/*
ti = dm_table_find_target(map, pos);
if (!dm_target_is_valid(ti)) {
/*
- * Must perform setup, that dm_done() requires,
+ * Must perform setup, that rq_completed() requires,
* before calling dm_kill_unmapped_request
*/
DMERR_LIMIT("request attempted access beyond the end of device");
- clone = dm_start_request(md, rq);
- dm_kill_unmapped_request(clone, -EIO);
+ dm_start_request(md, rq);
+ dm_kill_unmapped_request(rq, -EIO);
continue;
}
if (ti->type->busy && ti->type->busy(ti))
goto delay_and_out;
- clone = dm_start_request(md, rq);
-
- spin_unlock(q->queue_lock);
- if (map_request(ti, clone, md))
- goto requeued;
+ dm_start_request(md, rq);
+ tio = rq->special;
+ /* Establish tio->ti before queuing work (map_tio_request) */
+ tio->ti = ti;
+ queue_kthread_work(&md->kworker, &tio->work);
BUG_ON(!irqs_disabled());
- spin_lock(q->queue_lock);
}
goto out;
-requeued:
- BUG_ON(!irqs_disabled());
- spin_lock(q->queue_lock);
-
delay_and_out:
blk_delay_queue(q, HZ / 10);
out:
INIT_WORK(&md->work, dm_wq_work);
init_waitqueue_head(&md->eventq);
init_completion(&md->kobj_holder.completion);
+ md->kworker_task = NULL;
md->disk->major = _major;
md->disk->first_minor = minor;
unlock_fs(md);
bdput(md->bdev);
destroy_workqueue(md->wq);
+
+ if (md->kworker_task)
+ kthread_stop(md->kworker_task);
if (md->io_pool)
mempool_destroy(md->io_pool);
+ if (md->rq_pool)
+ mempool_destroy(md->rq_pool);
if (md->bs)
bioset_free(md->bs);
blk_integrity_unregister(md->disk);
bioset_free(md->bs);
md->bs = p->bs;
p->bs = NULL;
- } else if (dm_table_get_type(t) == DM_TYPE_REQUEST_BASED) {
- /*
- * There's no need to reload with request-based dm
- * because the size of front_pad doesn't change.
- * Note for future: If you are to reload bioset,
- * prep-ed requests in the queue may refer
- * to bio from the old bioset, so you must walk
- * through the queue to unprep.
- */
}
+ /*
+ * There's no need to reload with request-based dm
+ * because the size of front_pad doesn't change.
+ * Note for future: If you are to reload bioset,
+ * prep-ed requests in the queue may refer
+ * to bio from the old bioset, so you must walk
+ * through the queue to unprep.
+ */
goto out;
}
- BUG_ON(!p || md->io_pool || md->bs);
+ BUG_ON(!p || md->io_pool || md->rq_pool || md->bs);
md->io_pool = p->io_pool;
p->io_pool = NULL;
+ md->rq_pool = p->rq_pool;
+ p->rq_pool = NULL;
md->bs = p->bs;
p->bs = NULL;
return md->type;
}
+static bool dm_md_type_request_based(struct mapped_device *md)
+{
+ unsigned table_type = dm_get_md_type(md);
+
+ return (table_type == DM_TYPE_REQUEST_BASED ||
+ table_type == DM_TYPE_MQ_REQUEST_BASED);
+}
+
struct target_type *dm_get_immutable_target_type(struct mapped_device *md)
{
return md->immutable_target_type;
blk_queue_prep_rq(md->queue, dm_prep_fn);
blk_queue_lld_busy(md->queue, dm_lld_busy);
+ /* Also 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));
+
elv_register_queue(md->queue);
return 1;
*/
int dm_setup_md_queue(struct mapped_device *md)
{
- if ((dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) &&
- !dm_init_request_based_queue(md)) {
+ if (dm_md_type_request_based(md) && !dm_init_request_based_queue(md)) {
DMWARN("Cannot initialize queue for request-based mapped device");
return -EINVAL;
}
set_bit(DMF_FREEING, &md->flags);
spin_unlock(&_minor_lock);
+ if (dm_request_based(md))
+ flush_kthread_worker(&md->kworker);
+
if (!dm_suspended_md(md)) {
dm_table_presuspend_targets(map);
dm_table_postsuspend_targets(map);
* Stop md->queue before flushing md->wq in case request-based
* dm defers requests to md->wq from md->queue.
*/
- if (dm_request_based(md))
+ if (dm_request_based(md)) {
stop_queue(md->queue);
+ flush_kthread_worker(&md->kworker);
+ }
flush_workqueue(md->wq);
{
struct dm_md_mempools *pools = kzalloc(sizeof(*pools), GFP_KERNEL);
struct kmem_cache *cachep;
- unsigned int pool_size;
+ unsigned int pool_size = 0;
unsigned int front_pad;
if (!pools)
return NULL;
- if (type == DM_TYPE_BIO_BASED) {
+ switch (type) {
+ case DM_TYPE_BIO_BASED:
cachep = _io_cache;
pool_size = dm_get_reserved_bio_based_ios();
front_pad = roundup(per_bio_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone);
- } else if (type == DM_TYPE_REQUEST_BASED) {
- cachep = _rq_tio_cache;
+ break;
+ case DM_TYPE_REQUEST_BASED:
pool_size = dm_get_reserved_rq_based_ios();
+ pools->rq_pool = mempool_create_slab_pool(pool_size, _rq_cache);
+ if (!pools->rq_pool)
+ goto out;
+ /* fall through to setup remaining rq-based pools */
+ case DM_TYPE_MQ_REQUEST_BASED:
+ cachep = _rq_tio_cache;
+ if (!pool_size)
+ pool_size = dm_get_reserved_rq_based_ios();
front_pad = offsetof(struct dm_rq_clone_bio_info, clone);
/* per_bio_data_size is not used. See __bind_mempools(). */
WARN_ON(per_bio_data_size != 0);
- } else
+ break;
+ default:
goto out;
+ }
pools->io_pool = mempool_create_slab_pool(pool_size, cachep);
if (!pools->io_pool)
if (pools->io_pool)
mempool_destroy(pools->io_pool);
+ if (pools->rq_pool)
+ mempool_destroy(pools->rq_pool);
+
if (pools->bs)
bioset_free(pools->bs);
projects / linux-drm-fsl-dcu.git / blobdiff