Add a variant of blk_mq_init_queue that allows a previously allocated
queue to be initialized. blk_mq_init_allocated_queue models
blk_init_allocated_queue -- which was also created for DM's use.
DM's approach to device creation requires a placeholder request_queue be
allocated for use with alloc_dev() but the decision about what type of
request_queue will be ultimately created is deferred until all component
devices referenced in the DM table are processed to determine the table
type (request-based, blk-mq request-based, or bio-based).
Also, because of DM's late finalization of the request_queue type
the call to blk_mq_register_disk() doesn't happen during alloc_dev().
Must export blk_mq_register_disk() so that DM can backfill the 'mq' dir
once the blk-mq queue is fully allocated.
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxxxxx>
---
block/blk-mq-sysfs.c | 1 +
block/blk-mq.c | 30 ++++++++++++++++++++----------
include/linux/blk-mq.h | 2 ++
3 files changed, 23 insertions(+), 10 deletions(-)
diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index 1630a20..b79685e 100644
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c
@@ -436,6 +436,7 @@ int blk_mq_register_disk(struct gendisk *disk)
return 0;
}
+EXPORT_SYMBOL_GPL(blk_mq_register_disk);
void blk_mq_sysfs_unregister(struct request_queue *q)
{
diff --git a/block/blk-mq.c b/block/blk-mq.c
index b7b8933..3000121 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1891,9 +1891,25 @@ void blk_mq_release(struct request_queue *q)
struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
{
+ struct request_queue *uninit_q, *q;
+
+ uninit_q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node);
+ if (!uninit_q)
+ return ERR_PTR(-ENOMEM);
+
+ q = blk_mq_init_allocated_queue(set, uninit_q);
+ if (IS_ERR(q))
+ blk_cleanup_queue(uninit_q);
+
+ return q;
+}
+EXPORT_SYMBOL(blk_mq_init_queue);
+
+struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
+ struct request_queue *q)
+{
struct blk_mq_hw_ctx **hctxs;
struct blk_mq_ctx __percpu *ctx;
- struct request_queue *q;
unsigned int *map;
int i;
@@ -1928,17 +1944,13 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
hctxs[i]->queue_num = i;
}
- q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node);
- if (!q)
- goto err_hctxs;
-
/*
* Init percpu_ref in atomic mode so that it's faster to shutdown.
* See blk_register_queue() for details.
*/
if (percpu_ref_init(&q->mq_usage_counter, blk_mq_usage_counter_release,
PERCPU_REF_INIT_ATOMIC, GFP_KERNEL))
- goto err_mq_usage;
+ goto err_hctxs;
setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q);
blk_queue_rq_timeout(q, 30000);
@@ -1981,7 +1993,7 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
blk_mq_init_cpu_queues(q, set->nr_hw_queues);
if (blk_mq_init_hw_queues(q, set))
- goto err_mq_usage;
+ goto err_hctxs;
mutex_lock(&all_q_mutex);
list_add_tail(&q->all_q_node, &all_q_list);
@@ -1993,8 +2005,6 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
return q;
-err_mq_usage:
- blk_cleanup_queue(q);
err_hctxs:
kfree(map);
for (i = 0; i < set->nr_hw_queues; i++) {
@@ -2009,7 +2019,7 @@ err_percpu:
free_percpu(ctx);
return ERR_PTR(-ENOMEM);
}
-EXPORT_SYMBOL(blk_mq_init_queue);
+EXPORT_SYMBOL(blk_mq_init_allocated_queue);
void blk_mq_free_queue(struct request_queue *q)
{
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 7aec861..9a75c88 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -164,6 +164,8 @@ enum {
<< BLK_MQ_F_ALLOC_POLICY_START_BIT)
struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *);
+struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
+ struct request_queue *q);
void blk_mq_finish_init(struct request_queue *q);
int blk_mq_register_disk(struct gendisk *);
void blk_mq_unregister_disk(struct gendisk *);
--
1.9.5 (Apple Git-50.3)
--
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