[PATCH] Add struct request end_io callback

This is needed for several things, one in-tree user which I will introduce
after this patch.

This adds a ->end_io callback to struct request, so it can be used with
async io of any sort.  Right now users have to wait for completion in a
blocking manner.  In the next iteration, ->waiting can be folded into
->end_io_data since it is just a special case of that use.

From: Peter Osterlund <petero2@telia.com>

The problem is that the add-struct-request-end_io-callback patch forgot to
update pktcdvd.c.  This patch fixes it.

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Peter Osterlund <petero2@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 10 insertions, 1 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 5615a3c9e410..c7553066b917 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -93,6 +93,9 @@ struct io_context *get_io_context(int gfp_flags);
 void copy_io_context(struct io_context **pdst, struct io_context **psrc);
 void swap_io_context(struct io_context **ioc1, struct io_context **ioc2);
 
+struct request;
+typedef void (rq_end_io_fn)(struct request *);
+
 struct request_list {
 	int count[2];
 	int starved[2];
@@ -176,6 +179,12 @@ struct request {
 	 * For Power Management requests
 	 */
 	struct request_pm_state *pm;
+
+	/*
+	 * completion callback. end_io_data should be folded in with waiting
+	 */
+	rq_end_io_fn *end_io;
+	void *end_io_data;
 };
 
 /*
@@ -509,10 +518,10 @@ extern void blk_unregister_queue(struct gendisk *disk);
 extern void register_disk(struct gendisk *dev);
 extern void generic_make_request(struct bio *bio);
 extern void blk_put_request(struct request *);
+extern void blk_end_sync_rq(struct request *rq);
 extern void blk_attempt_remerge(request_queue_t *, struct request *);
 extern void __blk_attempt_remerge(request_queue_t *, struct request *);
 extern struct request *blk_get_request(request_queue_t *, int, int);
-extern void blk_put_request(struct request *);
 extern void blk_insert_request(request_queue_t *, struct request *, int, void *, int);
 extern void blk_requeue_request(request_queue_t *, struct request *);
 extern void blk_plug_device(request_queue_t *);