From ea435e1b9392a33deceaea2a16ebaa3397bead93 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 2 Nov 2017 21:29:54 +0300 Subject: [PATCH] block: add a poll_fn callback to struct request_queue That we we can also poll non blk-mq queues. Mostly needed for the NVMe multipath code, but could also be useful elsewhere. Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/blk-core.c | 11 +++++++++++ block/blk-mq.c | 14 +++++--------- drivers/nvme/target/io-cmd.c | 2 +- fs/block_dev.c | 4 ++-- fs/direct-io.c | 2 +- fs/iomap.c | 2 +- include/linux/blkdev.h | 4 +++- mm/page_io.c | 2 +- 8 files changed, 25 insertions(+), 16 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 68cfe6780a9b..395bfb10d658 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2321,6 +2321,17 @@ blk_qc_t submit_bio(struct bio *bio) } EXPORT_SYMBOL(submit_bio); +bool blk_poll(struct request_queue *q, blk_qc_t cookie) +{ + if (!q->poll_fn || !blk_qc_t_valid(cookie)) + return false; + + if (current->plug) + blk_flush_plug_list(current->plug, false); + return q->poll_fn(q, cookie); +} +EXPORT_SYMBOL_GPL(blk_poll); + /** * blk_cloned_rq_check_limits - Helper function to check a cloned request * for new the queue limits diff --git a/block/blk-mq.c b/block/blk-mq.c index e4d2490f4e7e..95ea5889b825 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -37,6 +37,7 @@ #include "blk-wbt.h" #include "blk-mq-sched.h" +static bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie); static void blk_mq_poll_stats_start(struct request_queue *q); static void blk_mq_poll_stats_fn(struct blk_stat_callback *cb); @@ -2499,6 +2500,8 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, spin_lock_init(&q->requeue_lock); blk_queue_make_request(q, blk_mq_make_request); + if (q->mq_ops->poll) + q->poll_fn = blk_mq_poll; /* * Do this after blk_queue_make_request() overrides it... @@ -2961,20 +2964,14 @@ static bool __blk_mq_poll(struct blk_mq_hw_ctx *hctx, struct request *rq) return false; } -bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie) +static bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie) { struct blk_mq_hw_ctx *hctx; - struct blk_plug *plug; struct request *rq; - if (!q->mq_ops || !q->mq_ops->poll || !blk_qc_t_valid(cookie) || - !test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) + if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) return false; - plug = current->plug; - if (plug) - blk_flush_plug_list(plug, false); - hctx = q->queue_hw_ctx[blk_qc_t_to_queue_num(cookie)]; if (!blk_qc_t_is_internal(cookie)) rq = blk_mq_tag_to_rq(hctx->tags, blk_qc_t_to_tag(cookie)); @@ -2992,7 +2989,6 @@ bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie) return __blk_mq_poll(hctx, rq); } -EXPORT_SYMBOL_GPL(blk_mq_poll); static int __init blk_mq_init(void) { diff --git a/drivers/nvme/target/io-cmd.c b/drivers/nvme/target/io-cmd.c index 0d4c23dc4532..db632818777d 100644 --- a/drivers/nvme/target/io-cmd.c +++ b/drivers/nvme/target/io-cmd.c @@ -94,7 +94,7 @@ static void nvmet_execute_rw(struct nvmet_req *req) cookie = submit_bio(bio); - blk_mq_poll(bdev_get_queue(req->ns->bdev), cookie); + blk_poll(bdev_get_queue(req->ns->bdev), cookie); } static void nvmet_execute_flush(struct nvmet_req *req) diff --git a/fs/block_dev.c b/fs/block_dev.c index 07ddccd17801..4afa4d5ff969 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -237,7 +237,7 @@ __blkdev_direct_IO_simple(struct kiocb *iocb, struct iov_iter *iter, if (!READ_ONCE(bio.bi_private)) break; if (!(iocb->ki_flags & IOCB_HIPRI) || - !blk_mq_poll(bdev_get_queue(bdev), qc)) + !blk_poll(bdev_get_queue(bdev), qc)) io_schedule(); } __set_current_state(TASK_RUNNING); @@ -402,7 +402,7 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages) break; if (!(iocb->ki_flags & IOCB_HIPRI) || - !blk_mq_poll(bdev_get_queue(bdev), qc)) + !blk_poll(bdev_get_queue(bdev), qc)) io_schedule(); } __set_current_state(TASK_RUNNING); diff --git a/fs/direct-io.c b/fs/direct-io.c index 62cf812ed0e5..d2bc339cb1e9 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -486,7 +486,7 @@ static struct bio *dio_await_one(struct dio *dio) dio->waiter = current; spin_unlock_irqrestore(&dio->bio_lock, flags); if (!(dio->iocb->ki_flags & IOCB_HIPRI) || - !blk_mq_poll(dio->bio_disk->queue, dio->bio_cookie)) + !blk_poll(dio->bio_disk->queue, dio->bio_cookie)) io_schedule(); /* wake up sets us TASK_RUNNING */ spin_lock_irqsave(&dio->bio_lock, flags); diff --git a/fs/iomap.c b/fs/iomap.c index 8194d30bdca0..4241bac905b1 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -1049,7 +1049,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, if (!(iocb->ki_flags & IOCB_HIPRI) || !dio->submit.last_queue || - !blk_mq_poll(dio->submit.last_queue, + !blk_poll(dio->submit.last_queue, dio->submit.cookie)) io_schedule(); } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index fddda6a1f9b5..225617dd0a3f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -266,6 +266,7 @@ struct blk_queue_ctx; typedef void (request_fn_proc) (struct request_queue *q); typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio); +typedef bool (poll_q_fn) (struct request_queue *q, blk_qc_t); typedef int (prep_rq_fn) (struct request_queue *, struct request *); typedef void (unprep_rq_fn) (struct request_queue *, struct request *); @@ -408,6 +409,7 @@ struct request_queue { request_fn_proc *request_fn; make_request_fn *make_request_fn; + poll_q_fn *poll_fn; prep_rq_fn *prep_rq_fn; unprep_rq_fn *unprep_rq_fn; softirq_done_fn *softirq_done_fn; @@ -975,7 +977,7 @@ extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, int blk_status_to_errno(blk_status_t status); blk_status_t errno_to_blk_status(int errno); -bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie); +bool blk_poll(struct request_queue *q, blk_qc_t cookie); static inline struct request_queue *bdev_get_queue(struct block_device *bdev) { diff --git a/mm/page_io.c b/mm/page_io.c index 21502d341a67..ff04de630c46 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -407,7 +407,7 @@ int swap_readpage(struct page *page, bool do_poll) if (!READ_ONCE(bio->bi_private)) break; - if (!blk_mq_poll(disk->queue, qc)) + if (!blk_poll(disk->queue, qc)) break; } __set_current_state(TASK_RUNNING); -- 2.11.0