History

block: allow initialization of previously allocated request_queue

blk_init_queue() allocates the request_queue structure and then initializes it as needed (request_fn, elevator, etc). Split initialization out to blk_init_allocated_queue_node. Introduce blk_init_allocated_queue wrapper function to model existing blk_init_queue and blk_init_queue_node interfaces. Export elv_register_queue to allow a newly added elevator to be registered with sysfs. Export elv_unregister_queue for symmetry. These changes allow DM to initialize a device's request_queue with more precision. In particular, DM no longer unconditionally initializes a full request_queue (elevator et al). It only does so for a request-based DM device.

Mike Snitzer committed 16 years ago

Commit 01effb01 parent 0f3942a3 files · +24 −1Browse files

Unified · Split

3 files
  1. block/blk-core.c +17 −1
  2. block/elevator.c +2 −0
  3. include/linux/blkdev.h +5 −0
block/blk-core.c+17−1
@@ -572,6 +572,22 @@ blk_init_queue_node(request_fn_proc *rfn, spinlock_t *lock, int node_id) · 571 unmodified lines
572{572{
573 struct request_queue *q = blk_alloc_queue_node(GFP_KERNEL, node_id);573 struct request_queue *q = blk_alloc_queue_node(GFP_KERNEL, node_id);
574 574
575 return blk_init_allocated_queue_node(q, rfn, lock, node_id);
576}
577EXPORT_SYMBOL(blk_init_queue_node);
578
579struct request_queue *
580blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn,
581 spinlock_t *lock)
582{
583 return blk_init_allocated_queue_node(q, rfn, lock, -1);
584}
585EXPORT_SYMBOL(blk_init_allocated_queue);
586
587struct request_queue *
588blk_init_allocated_queue_node(struct request_queue *q, request_fn_proc *rfn,
589 spinlock_t *lock, int node_id)
590{
575 if (!q)591 if (!q)
576 return NULL;592 return NULL;
577 593
@@ -605,7 +621,7 @@ blk_init_queue_node(request_fn_proc *rfn, spinlock_t *lock, int node_id) · 27 unmodified lines
605 blk_put_queue(q);621 blk_put_queue(q);
606 return NULL;622 return NULL;
607}623}
608EXPORT_SYMBOL(blk_init_queue_node);624EXPORT_SYMBOL(blk_init_allocated_queue_node);
609 625
610int blk_get_queue(struct request_queue *q)626int blk_get_queue(struct request_queue *q)
611{627{
block/elevator.c+2−0
@@ -930,6 +930,7 @@ int elv_register_queue(struct request_queue *q) · 929 unmodified lines
930 }930 }
931 return error;931 return error;
932}932}
933EXPORT_SYMBOL(elv_register_queue);
933 934
934static void __elv_unregister_queue(struct elevator_queue *e)935static void __elv_unregister_queue(struct elevator_queue *e)
935{936{
@@ -942,6 +943,7 @@ void elv_unregister_queue(struct request_queue *q) · 6 unmodified lines
942 if (q)943 if (q)
943 __elv_unregister_queue(q->elevator);944 __elv_unregister_queue(q->elevator);
944}945}
946EXPORT_SYMBOL(elv_unregister_queue);
945 947
946void elv_register(struct elevator_type *e)948void elv_register(struct elevator_type *e)
947{949{
include/linux/blkdev.h+5−0
@@ -921,7 +921,12 @@ extern void blk_abort_queue(struct request_queue *); · 920 unmodified lines
921 */921 */
922extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,922extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
923 spinlock_t *lock, int node_id);923 spinlock_t *lock, int node_id);
924extern struct request_queue *blk_init_allocated_queue_node(struct request_queue *,
925 request_fn_proc *,
926 spinlock_t *, int node_id);
924extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);927extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
928extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
929 request_fn_proc *, spinlock_t *);
925extern void blk_cleanup_queue(struct request_queue *);930extern void blk_cleanup_queue(struct request_queue *);
926extern void blk_queue_make_request(struct request_queue *, make_request_fn *);931extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
927extern void blk_queue_bounce_limit(struct request_queue *, u64);932extern void blk_queue_bounce_limit(struct request_queue *, u64);