From: Keith Busch <keith.busch@xxxxxxxxx>
For blk-mq request-based DM the responsibility of allocating a cloned
request is transfered from DM core to the target type so that the cloned
request is allocated from the appropriate request_queue's pool and
initialized for the target block device. The original request's
'special' now points to the dm_rq_target_io because the clone is
allocated later in the block layer rather than in DM core.
Care was taken to preserve compatibility with old-style block request
completion that requires request-based DM _not_ acquire the clone
request's queue lock in the completion path. As such, there are now 2
different request-based dm_target interfaces:
1) the original .map_rq() interface will continue to be used for
non-blk-mq devices -- the preallocated clone request is passed in
from DM core.
2) a new .clone_and_map_rq() and .release_clone_rq() will be used for
blk-mq devices -- blk_get_request() and blk_put_request() are used
respectively from these hooks.
dm_table_set_type() was updated to detect if the request-based target is
being stacked on blk-mq devices, if so DM_TYPE_MQ_REQUEST_BASED is set.
DM core disallows switching the DM table's type after it is set. This
means that there is no mixing of non-blk-mq and blk-mq devices within
the same request-based DM table.
Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
---
drivers/md/dm-mpath.c | 53 ++++++++--
drivers/md/dm-table.c | 34 +++++-
drivers/md/dm-target.c | 15 ++-
drivers/md/dm.c | 233 +++++++++++++++++++++++++-----------------
drivers/md/dm.h | 8 +-
include/linux/device-mapper.h | 7 ++
6 files changed, 239 insertions(+), 111 deletions(-)
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 7b6b0f0..df408bc 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -11,6 +11,7 @@
#include "dm-path-selector.h"
#include "dm-uevent.h"
+#include <linux/blkdev.h>
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/mempool.h>
@@ -378,18 +379,18 @@ static int __must_push_back(struct multipath *m)
/*
* Map cloned requests
*/
-static int multipath_map(struct dm_target *ti, struct request *clone,
- union map_info *map_context)
+static int __multipath_map(struct dm_target *ti, struct request *clone,
+ union map_info *map_context,
+ struct request *rq, struct request **__clone)
{
struct multipath *m = (struct multipath *) ti->private;
int r = DM_MAPIO_REQUEUE;
- size_t nr_bytes = blk_rq_bytes(clone);
- unsigned long flags;
+ size_t nr_bytes = clone ? blk_rq_bytes(clone) : blk_rq_bytes(rq);
struct pgpath *pgpath;
struct block_device *bdev;
struct dm_mpath_io *mpio;
- spin_lock_irqsave(&m->lock, flags);
+ spin_lock(&m->lock);
/* Do we need to select a new pgpath? */
if (!m->current_pgpath ||
@@ -412,9 +413,21 @@ static int multipath_map(struct dm_target *ti, struct request *clone,
goto out_unlock;
bdev = pgpath->path.dev->bdev;
- clone->q = bdev_get_queue(bdev);
- clone->rq_disk = bdev->bd_disk;
- clone->cmd_flags |= REQ_FAILFAST_TRANSPORT;
+
+ if (clone) {
+ /* Old request-based interface: allocated clone is passed in */
+ clone->q = bdev_get_queue(bdev);
+ clone->rq_disk = bdev->bd_disk;
+ clone->cmd_flags |= REQ_FAILFAST_TRANSPORT;
+ } else {
+ /* blk-mq request-based interface */
+ *__clone = blk_get_request(bdev_get_queue(bdev),
+ rq_data_dir(rq), GFP_KERNEL);
+ if (IS_ERR(*__clone))
+ goto out_unlock;
+ (*__clone)->cmd_flags |= REQ_FAILFAST_TRANSPORT;
+ }
+
mpio = map_context->ptr;
mpio->pgpath = pgpath;
mpio->nr_bytes = nr_bytes;
@@ -425,11 +438,29 @@ static int multipath_map(struct dm_target *ti, struct request *clone,
r = DM_MAPIO_REMAPPED;
out_unlock:
- spin_unlock_irqrestore(&m->lock, flags);
+ spin_unlock(&m->lock);
return r;
}
+static int multipath_map(struct dm_target *ti, struct request *clone,
+ union map_info *map_context)
+{
+ return __multipath_map(ti, clone, map_context, NULL, NULL);
+}
+
+static int multipath_clone_and_map(struct dm_target *ti, struct request *rq,
+ union map_info *map_context,
+ struct request **clone)
+{
+ return __multipath_map(ti, NULL, map_context, rq, clone);
+}
+
+static void multipath_release_clone(struct request *clone)
+{
+ blk_put_request(clone);
+}
+
/*
* If we run out of usable paths, should we queue I/O or error it?
*/
@@ -1666,11 +1697,13 @@ out:
*---------------------------------------------------------------*/
static struct target_type multipath_target = {
.name = "multipath",
- .version = {1, 7, 0},
+ .version = {1, 8, 0},
.module = THIS_MODULE,
.ctr = multipath_ctr,
.dtr = multipath_dtr,
.map_rq = multipath_map,
+ .clone_and_map_rq = multipath_clone_and_map,
+ .release_clone_rq = multipath_release_clone,
.rq_end_io = multipath_end_io,
.presuspend = multipath_presuspend,
.postsuspend = multipath_postsuspend,
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 3afae9e..2d7e373 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -827,6 +827,7 @@ static int dm_table_set_type(struct dm_table *t)
{
unsigned i;
unsigned bio_based = 0, request_based = 0, hybrid = 0;
+ bool use_blk_mq = false;
struct dm_target *tgt;
struct dm_dev_internal *dd;
struct list_head *devices;
@@ -872,11 +873,26 @@ static int dm_table_set_type(struct dm_table *t)
/* Non-request-stackable devices can't be used for request-based dm */
devices = dm_table_get_devices(t);
list_for_each_entry(dd, devices, list) {
- if (!blk_queue_stackable(bdev_get_queue(dd->dm_dev->bdev))) {
- DMWARN("table load rejected: including"
- " non-request-stackable devices");
+ struct request_queue *q = bdev_get_queue(dd->dm_dev->bdev);
+
+ if (!blk_queue_stackable(q)) {
+ DMERR("table load rejected: including"
+ " non-request-stackable devices");
return -EINVAL;
}
+
+ if (q->mq_ops)
+ use_blk_mq = true;
+ }
+
+ if (use_blk_mq) {
+ /* verify _all_ devices in the table are blk-mq devices */
+ list_for_each_entry(dd, devices, list)
+ if (!bdev_get_queue(dd->dm_dev->bdev)->mq_ops) {
+ DMERR("table load rejected: not all devices"
+ " are blk-mq request-stackable");
+ return -EINVAL;
+ }
}
/*
@@ -890,7 +906,7 @@ static int dm_table_set_type(struct dm_table *t)
return -EINVAL;
}
- t->type = DM_TYPE_REQUEST_BASED;
+ t->type = !use_blk_mq ? DM_TYPE_REQUEST_BASED : DM_TYPE_MQ_REQUEST_BASED;
return 0;
}
@@ -907,7 +923,15 @@ struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
bool dm_table_request_based(struct dm_table *t)
{
- return dm_table_get_type(t) == DM_TYPE_REQUEST_BASED;
+ unsigned table_type = dm_table_get_type(t);
+
+ return (table_type == DM_TYPE_REQUEST_BASED ||
+ table_type == DM_TYPE_MQ_REQUEST_BASED);
+}
+
+bool dm_table_mq_request_based(struct dm_table *t)
+{
+ return dm_table_get_type(t) == DM_TYPE_MQ_REQUEST_BASED;
}
static int dm_table_alloc_md_mempools(struct dm_table *t)
diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c
index 242e3ce..925ec1b 100644
--- a/drivers/md/dm-target.c
+++ b/drivers/md/dm-target.c
@@ -137,13 +137,26 @@ static int io_err_map_rq(struct dm_target *ti, struct request *clone,
return -EIO;
}
+static int io_err_clone_and_map_rq(struct dm_target *ti, struct request *rq,
+ union map_info *map_context,
+ struct request **clone)
+{
+ return -EIO;
+}
+
+static void io_err_release_clone_rq(struct request *clone)
+{
+}
+
static struct target_type error_target = {
.name = "error",
- .version = {1, 2, 0},
+ .version = {1, 3, 0},
.ctr = io_err_ctr,
.dtr = io_err_dtr,
.map = io_err_map,
.map_rq = io_err_map_rq,
+ .clone_and_map_rq = io_err_clone_and_map_rq,
+ .release_clone_rq = io_err_release_clone_rq,
};
int __init dm_target_init(void)
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 00c9986..1955710 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1016,7 +1016,7 @@ static void end_clone_bio(struct bio *clone, int error)
* 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]);
@@ -1044,13 +1044,17 @@ static void free_rq_clone(struct request *clone)
struct dm_rq_target_io *tio = clone->end_io_data;
blk_rq_unprep_clone(clone);
- free_clone_request(tio->md, clone);
+ if (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)
{
@@ -1079,23 +1083,23 @@ 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.
*/
-static 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;
@@ -1105,7 +1109,14 @@ static void dm_requeue_unmapped_request(struct request *clone)
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);
}
static void __stop_queue(struct request_queue *q)
@@ -1175,8 +1186,15 @@ static void dm_done(struct request *clone, int error, bool mapped)
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;
@@ -1188,13 +1206,11 @@ static void dm_softirq_done(struct request *rq)
* 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);
}
@@ -1202,39 +1218,40 @@ static void dm_complete_request(struct request *clone, int 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() function fails.
+ * 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 *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);
}
/*
- * 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);
}
/*
@@ -1712,16 +1729,17 @@ static void dm_request(struct request_queue *q, struct bio *bio)
_dm_request(q, bio);
}
-static 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);
}
@@ -1760,8 +1778,8 @@ static int setup_clone(struct request *clone, struct request *rq,
return 0;
}
-static struct request *__clone_rq(struct request *rq, struct mapped_device *md,
- struct dm_rq_target_io *tio, gfp_t gfp_mask)
+static struct request *clone_rq(struct request *rq, struct mapped_device *md,
+ struct dm_rq_target_io *tio, gfp_t gfp_mask)
{
struct request *clone = alloc_clone_request(md, gfp_mask);
@@ -1780,11 +1798,12 @@ static struct request *__clone_rq(struct request *rq, struct mapped_device *md,
static void map_tio_request(struct kthread_work *work);
-static struct request *clone_rq(struct request *rq, struct mapped_device *md,
- gfp_t gfp_mask)
+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)
@@ -1798,13 +1817,17 @@ static struct request *clone_rq(struct request *rq, struct mapped_device *md,
memset(&tio->info, 0, sizeof(tio->info));
init_kthread_work(&tio->work, map_tio_request);
- clone = __clone_rq(rq, md, tio, GFP_ATOMIC);
- if (!clone) {
- free_rq_tio(tio);
- return NULL;
+ table = dm_get_live_table(md, &srcu_idx);
+ if (!dm_table_mq_request_based(table)) {
+ if (!clone_rq(rq, md, tio, GFP_ATOMIC)) {
+ dm_put_live_table(md, srcu_idx);
+ free_rq_tio(tio);
+ return NULL;
+ }
}
+ dm_put_live_table(md, srcu_idx);
- return clone;
+ return tio;
}
/*
@@ -1813,18 +1836,18 @@ static struct request *clone_rq(struct request *rq, struct mapped_device *md,
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;
@@ -1832,17 +1855,31 @@ static int dm_prep_fn(struct request_queue *q, struct request *rq)
/*
* Returns:
- * 0 : the request has been processed (not requeued)
- * !0 : the request has been requeued
+ * 0 : the request has been processed (not requeued)
+ * 1 : the request has been requeued
+ * < 0 : the original request needs to be requeued
*/
-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;
+ struct request *clone = NULL;
+ int r, r2, requeued = 0;
+ struct dm_rq_target_io *tio = rq->special;
+
+ 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 (IS_ERR(clone))
+ return PTR_ERR(clone);
+ r2 = setup_clone(clone, rq, tio, GFP_KERNEL);
+ if (r2) {
+ ti->type->release_clone_rq(clone);
+ return r2;
+ }
+ }
- 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 */
@@ -1850,8 +1887,8 @@ static int map_request(struct dm_target *ti, struct request *clone,
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 */
@@ -1865,7 +1902,7 @@ static int map_request(struct dm_target *ti, struct request *clone,
}
/* The target wants to complete the I/O */
- dm_kill_unmapped_request(clone, r);
+ dm_kill_unmapped_request(rq, r);
break;
}
@@ -1875,17 +1912,17 @@ static int map_request(struct dm_target *ti, struct request *clone,
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;
- map_request(tio->ti, tio->clone, tio->md);
+ if (map_request(tio->ti, rq, md) < 0)
+ dm_requeue_unmapped_original_request(md, rq);
}
-static struct request *dm_start_request(struct mapped_device *md, struct request *orig)
+static void dm_start_request(struct mapped_device *md, struct request *orig)
{
- struct request *clone;
-
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.
@@ -1895,8 +1932,6 @@ static struct request *dm_start_request(struct mapped_device *md, struct request
* See the comment in rq_completed() too.
*/
dm_get(md);
-
- return clone;
}
/*
@@ -1909,7 +1944,7 @@ static void dm_request_fn(struct request_queue *q)
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;
@@ -1932,19 +1967,19 @@ static void dm_request_fn(struct request_queue *q)
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);
+ dm_start_request(md, rq);
tio = rq->special;
/* Establish tio->ti before queuing work (map_tio_request) */
@@ -2241,16 +2276,15 @@ static void __bind_mempools(struct mapped_device *md, struct dm_table *t)
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;
}
@@ -2462,6 +2496,14 @@ unsigned dm_get_md_type(struct mapped_device *md)
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;
@@ -2514,8 +2556,7 @@ static int dm_init_request_based_queue(struct mapped_device *md)
*/
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;
}
@@ -3187,27 +3228,35 @@ struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity, u
{
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)
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 84b0f9e4..84d7978 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -34,9 +34,10 @@
/*
* Type of table and mapped_device's mempool
*/
-#define DM_TYPE_NONE 0
-#define DM_TYPE_BIO_BASED 1
-#define DM_TYPE_REQUEST_BASED 2
+#define DM_TYPE_NONE 0
+#define DM_TYPE_BIO_BASED 1
+#define DM_TYPE_REQUEST_BASED 2
+#define DM_TYPE_MQ_REQUEST_BASED 3
/*
* List of devices that a metadevice uses and should open/close.
@@ -73,6 +74,7 @@ int dm_table_any_busy_target(struct dm_table *t);
unsigned dm_table_get_type(struct dm_table *t);
struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);
bool dm_table_request_based(struct dm_table *t);
+bool dm_table_mq_request_based(struct dm_table *t);
void dm_table_free_md_mempools(struct dm_table *t);
struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 19296fb..2646aed 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -48,6 +48,11 @@ typedef void (*dm_dtr_fn) (struct dm_target *ti);
typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio);
typedef int (*dm_map_request_fn) (struct dm_target *ti, struct request *clone,
union map_info *map_context);
+typedef int (*dm_clone_and_map_request_fn) (struct dm_target *ti,
+ struct request *rq,
+ union map_info *map_context,
+ struct request **clone);
+typedef void (*dm_release_clone_request_fn) (struct request *clone);
/*
* Returns:
@@ -143,6 +148,8 @@ struct target_type {
dm_dtr_fn dtr;
dm_map_fn map;
dm_map_request_fn map_rq;
+ dm_clone_and_map_request_fn clone_and_map_rq;
+ dm_release_clone_request_fn release_clone_rq;
dm_endio_fn end_io;
dm_request_endio_fn rq_end_io;
dm_presuspend_fn presuspend;
--
1.9.3
--
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