blk-mq: split out tag initialization, support shared tags
Add a new blk_mq_tag_set structure that gets set up before we initialize
the queue. A single blk_mq_tag_set structure can be shared by multiple
queues.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Modular export of blk_mq_{alloc,free}_tagset added by me.
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 29c1a6e..a4ea0ce 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -33,8 +33,6 @@
unsigned int nr_ctx_map;
unsigned long *ctx_map;
- struct request **rqs;
- struct list_head page_list;
struct blk_mq_tags *tags;
unsigned long queued;
@@ -42,7 +40,6 @@
#define BLK_MQ_MAX_DISPATCH_ORDER 10
unsigned long dispatched[BLK_MQ_MAX_DISPATCH_ORDER];
- unsigned int queue_depth;
unsigned int numa_node;
unsigned int cmd_size; /* per-request extra data */
@@ -50,7 +47,7 @@
struct kobject kobj;
};
-struct blk_mq_reg {
+struct blk_mq_tag_set {
struct blk_mq_ops *ops;
unsigned int nr_hw_queues;
unsigned int queue_depth;
@@ -59,18 +56,22 @@
int numa_node;
unsigned int timeout;
unsigned int flags; /* BLK_MQ_F_* */
+ void *driver_data;
+
+ struct blk_mq_tags **tags;
};
typedef int (queue_rq_fn)(struct blk_mq_hw_ctx *, struct request *);
typedef struct blk_mq_hw_ctx *(map_queue_fn)(struct request_queue *, const int);
-typedef struct blk_mq_hw_ctx *(alloc_hctx_fn)(struct blk_mq_reg *,unsigned int);
+typedef struct blk_mq_hw_ctx *(alloc_hctx_fn)(struct blk_mq_tag_set *,
+ unsigned int);
typedef void (free_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int);
typedef int (init_hctx_fn)(struct blk_mq_hw_ctx *, void *, unsigned int);
typedef void (exit_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int);
-typedef int (init_request_fn)(void *, struct blk_mq_hw_ctx *,
- struct request *, unsigned int);
-typedef void (exit_request_fn)(void *, struct blk_mq_hw_ctx *,
- struct request *, unsigned int);
+typedef int (init_request_fn)(void *, struct request *, unsigned int,
+ unsigned int, unsigned int);
+typedef void (exit_request_fn)(void *, struct request *, unsigned int,
+ unsigned int);
struct blk_mq_ops {
/*
@@ -127,10 +128,13 @@
BLK_MQ_MAX_DEPTH = 2048,
};
-struct request_queue *blk_mq_init_queue(struct blk_mq_reg *, void *);
+struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *);
int blk_mq_register_disk(struct gendisk *);
void blk_mq_unregister_disk(struct gendisk *);
+int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set);
+void blk_mq_free_tag_set(struct blk_mq_tag_set *set);
+
void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule);
void blk_mq_insert_request(struct request *, bool, bool, bool);
@@ -139,10 +143,10 @@
bool blk_mq_can_queue(struct blk_mq_hw_ctx *);
struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp);
struct request *blk_mq_alloc_reserved_request(struct request_queue *q, int rw, gfp_t gfp);
-struct request *blk_mq_rq_from_tag(struct request_queue *q, unsigned int tag);
+struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag);
struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *, const int ctx_index);
-struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_reg *, unsigned int);
+struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_tag_set *, unsigned int);
void blk_mq_free_single_hw_queue(struct blk_mq_hw_ctx *, unsigned int);
bool blk_mq_end_io_partial(struct request *rq, int error,
@@ -173,12 +177,6 @@
return (void *) rq + sizeof(*rq);
}
-static inline struct request *blk_mq_tag_to_rq(struct blk_mq_hw_ctx *hctx,
- unsigned int tag)
-{
- return hctx->rqs[tag];
-}
-
#define queue_for_each_hw_ctx(q, hctx, i) \
for ((i) = 0; (i) < (q)->nr_hw_queues && \
({ hctx = (q)->queue_hw_ctx[i]; 1; }); (i)++)