From a0cd128542cd9c67f27458a08e989db486a293ce Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 21 Sep 2007 10:41:07 +0200 Subject: [PATCH] block: add end_queued_request() and end_dequeued_request() helpers We can use this helper in the elevator core for BLKPREP_KILL, and it'll also be useful for the empty barrier patch. Signed-off-by: Jens Axboe --- block/elevator.c | 9 +---- block/ll_rw_blk.c | 78 +++++++++++++++++++++++++++++++++++++++--- include/linux/blkdev.h | 4 ++- 3 files changed, 77 insertions(+), 14 deletions(-) diff --git a/block/elevator.c b/block/elevator.c index b9c518afe1..ec23ca02f2 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -751,15 +751,8 @@ struct request *elv_next_request(struct request_queue *q) rq = NULL; break; } else if (ret == BLKPREP_KILL) { - int nr_bytes = rq->hard_nr_sectors << 9; - - if (!nr_bytes) - nr_bytes = rq->data_len; - - blkdev_dequeue_request(rq); rq->cmd_flags |= REQ_QUIET; - end_that_request_chunk(rq, 0, nr_bytes); - end_that_request_last(rq, 0); + end_queued_request(rq, 0); } else { printk(KERN_ERR "%s: bad return=%d\n", __FUNCTION__, ret); diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index 0fa5d3d556..8904f8b1f4 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -3630,15 +3630,83 @@ void end_that_request_last(struct request *req, int uptodate) EXPORT_SYMBOL(end_that_request_last); -void end_request(struct request *req, int uptodate) +static inline void __end_request(struct request *rq, int uptodate, + unsigned int nr_bytes, int dequeue) { - if (!end_that_request_first(req, uptodate, req->hard_cur_sectors)) { - add_disk_randomness(req->rq_disk); - blkdev_dequeue_request(req); - end_that_request_last(req, uptodate); + if (!end_that_request_chunk(rq, uptodate, nr_bytes)) { + if (dequeue) + blkdev_dequeue_request(rq); + add_disk_randomness(rq->rq_disk); + end_that_request_last(rq, uptodate); } } +static unsigned int rq_byte_size(struct request *rq) +{ + if (blk_fs_request(rq)) + return rq->hard_nr_sectors << 9; + + return rq->data_len; +} + +/** + * end_queued_request - end all I/O on a queued request + * @rq: the request being processed + * @uptodate: error value or 0/1 uptodate flag + * + * Description: + * Ends all I/O on a request, and removes it from the block layer queues. + * Not suitable for normal IO completion, unless the driver still has + * the request attached to the block layer. + * + **/ +void end_queued_request(struct request *rq, int uptodate) +{ + __end_request(rq, uptodate, rq_byte_size(rq), 1); +} +EXPORT_SYMBOL(end_queued_request); + +/** + * end_dequeued_request - end all I/O on a dequeued request + * @rq: the request being processed + * @uptodate: error value or 0/1 uptodate flag + * + * Description: + * Ends all I/O on a request. The request must already have been + * dequeued using blkdev_dequeue_request(), as is normally the case + * for most drivers. + * + **/ +void end_dequeued_request(struct request *rq, int uptodate) +{ + __end_request(rq, uptodate, rq_byte_size(rq), 0); +} +EXPORT_SYMBOL(end_dequeued_request); + + +/** + * end_request - end I/O on the current segment of the request + * @rq: the request being processed + * @uptodate: error value or 0/1 uptodate flag + * + * Description: + * Ends I/O on the current segment of a request. If that is the only + * remaining segment, the request is also completed and freed. + * + * This is a remnant of how older block drivers handled IO completions. + * Modern drivers typically end IO on the full request in one go, unless + * they have a residual value to account for. For that case this function + * isn't really useful, unless the residual just happens to be the + * full current segment. In other words, don't use this function in new + * code. Either use end_request_completely(), or the + * end_that_request_chunk() (along with end_that_request_last()) for + * partial completions. + * + **/ +void end_request(struct request *req, int uptodate) +{ + __end_request(req, uptodate, req->hard_cur_sectors << 9, 1); +} EXPORT_SYMBOL(end_request); static void blk_rq_bio_prep(struct request_queue *q, struct request *rq, diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 5ed888b04b..610967992d 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -729,7 +729,9 @@ static inline void blk_run_address_space(struct address_space *mapping) extern int end_that_request_first(struct request *, int, int); extern int end_that_request_chunk(struct request *, int, int); extern void end_that_request_last(struct request *, int); -extern void end_request(struct request *req, int uptodate); +extern void end_request(struct request *, int); +extern void end_queued_request(struct request *, int); +extern void end_dequeued_request(struct request *, int); extern void blk_complete_request(struct request *); /* -- 2.39.5