[PATCH v5 03/10] block: introduce blk_init_flush and its pair

Ming Lei
2014-09-25T15:24:19Z

These two temporary functions are introduced for holding flush
initialization and de-initialization, so that we can
introduce 'flush queue' easier in the following patch. And
once 'flush queue' and its allocation/free functions are ready,
they will be removed for sake of code readability.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
---
block/blk-core.c | 5 ++---
block/blk-flush.c | 19 ++++++++++++++++++-
block/blk-mq.c | 2 +-
block/blk-mq.h | 1 -
block/blk-sysfs.c | 4 ++--
block/blk.h | 3 +++
6 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 5bd9a04..215490a 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -705,8 +705,7 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn,
if (!q)
return NULL;

- q->flush_rq = kzalloc(sizeof(struct request), GFP_KERNEL);
- if (!q->flush_rq)
+ if (blk_init_flush(q))
return NULL;

if (blk_init_rl(&q->root_rl, q, GFP_KERNEL))
@@ -742,7 +741,7 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn,
return q;

fail:
- kfree(q->flush_rq);
+ blk_exit_flush(q);
return NULL;
}
EXPORT_SYMBOL(blk_init_allocated_queue);
diff --git a/block/blk-flush.c b/block/blk-flush.c
index 55028a7..c72ab32 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -472,7 +472,7 @@ int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
}
EXPORT_SYMBOL(blkdev_issue_flush);

-int blk_mq_init_flush(struct request_queue *q)
+static int blk_mq_init_flush(struct request_queue *q)
{
struct blk_mq_tag_set *set = q->tag_set;

@@ -485,3 +485,20 @@ int blk_mq_init_flush(struct request_queue *q)
return -ENOMEM;
return 0;
}
+
+int blk_init_flush(struct request_queue *q)
+{
+ if (q->mq_ops)
+ return blk_mq_init_flush(q);
+
+ q->flush_rq = kzalloc(sizeof(struct request), GFP_KERNEL);
+ if (!q->flush_rq)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void blk_exit_flush(struct request_queue *q)
+{
+ kfree(q->flush_rq);
+}
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 80c2cd2..5acdec4 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1860,7 +1860,7 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)

blk_mq_add_queue_tag_set(set, q);

- if (blk_mq_init_flush(q))
+ if (blk_init_flush(q))
goto err_hw_queues;

blk_mq_map_swqueue(q);
diff --git a/block/blk-mq.h b/block/blk-mq.h
index ecac69c..d567d52 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -27,7 +27,6 @@ struct blk_mq_ctx {

void __blk_mq_complete_request(struct request *rq);
void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
-int blk_mq_init_flush(struct request_queue *q);
void blk_mq_freeze_queue(struct request_queue *q);
void blk_mq_free_queue(struct request_queue *q);
void blk_mq_clone_flush_request(struct request *flush_rq,
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 17f5c84..9490759 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -517,11 +517,11 @@ static void blk_release_queue(struct kobject *kobj)
if (q->queue_tags)
__blk_queue_free_tags(q);

+ blk_exit_flush(q);
+
if (q->mq_ops)
blk_mq_free_queue(q);

- kfree(q->flush_rq);
-
blk_trace_shutdown(q);

bdi_destroy(&q->backing_dev_info);
diff --git a/block/blk.h b/block/blk.h
index e515a28..c6fa3d4 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -22,6 +22,9 @@ static inline void __blk_get_queue(struct request_queue *q)
kobject_get(&q->kobj);
}

+int blk_init_flush(struct request_queue *q);
+void blk_exit_flush(struct request_queue *q);
+
int blk_init_rl(struct request_list *rl, struct request_queue *q,
gfp_t gfp_mask);
void blk_exit_rl(struct request_list *rl);
--
1.7.9.5