From 6d2809d51a5079f01a416d91dd63b0766cb685d0 Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Mon, 27 Feb 2017 10:28:27 -0800 Subject: [PATCH] blk-mq: make blk_mq_alloc_request_hctx() allocate a scheduler request blk_mq_alloc_request_hctx() allocates a driver request directly, unlike its blk_mq_alloc_request() counterpart. It also crashes because it doesn't update the tags->rqs map. Fix it by making it allocate a scheduler request. Reported-by: Sagi Grimberg Signed-off-by: Omar Sandoval Signed-off-by: Jens Axboe Tested-by: Sagi Grimberg --- block/blk-mq-sched.c | 11 +++++------ block/blk-mq.c | 33 +++++++++++++++------------------ 2 files changed, 20 insertions(+), 24 deletions(-) diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 46ca965fff5c..5697b23412a1 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -110,15 +110,14 @@ struct request *blk_mq_sched_get_request(struct request_queue *q, struct blk_mq_alloc_data *data) { struct elevator_queue *e = q->elevator; - struct blk_mq_hw_ctx *hctx; - struct blk_mq_ctx *ctx; struct request *rq; blk_queue_enter_live(q); - ctx = blk_mq_get_ctx(q); - hctx = blk_mq_map_queue(q, ctx->cpu); - - blk_mq_set_alloc_data(data, q, data->flags, ctx, hctx); + data->q = q; + if (likely(!data->ctx)) + data->ctx = blk_mq_get_ctx(q); + if (likely(!data->hctx)) + data->hctx = blk_mq_map_queue(q, data->ctx->cpu); if (e) { data->flags |= BLK_MQ_REQ_INTERNAL; diff --git a/block/blk-mq.c b/block/blk-mq.c index 4df5fb42c74f..85a7047d8b03 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -273,10 +273,9 @@ EXPORT_SYMBOL(blk_mq_alloc_request); struct request *blk_mq_alloc_request_hctx(struct request_queue *q, int rw, unsigned int flags, unsigned int hctx_idx) { - struct blk_mq_hw_ctx *hctx; - struct blk_mq_ctx *ctx; + struct blk_mq_alloc_data alloc_data = { .flags = flags }; struct request *rq; - struct blk_mq_alloc_data alloc_data; + unsigned int cpu; int ret; /* @@ -299,25 +298,23 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, int rw, * Check if the hardware context is actually mapped to anything. * If not tell the caller that it should skip this queue. */ - hctx = q->queue_hw_ctx[hctx_idx]; - if (!blk_mq_hw_queue_mapped(hctx)) { - ret = -EXDEV; - goto out_queue_exit; + alloc_data.hctx = q->queue_hw_ctx[hctx_idx]; + if (!blk_mq_hw_queue_mapped(alloc_data.hctx)) { + blk_queue_exit(q); + return ERR_PTR(-EXDEV); } - ctx = __blk_mq_get_ctx(q, cpumask_first(hctx->cpumask)); + cpu = cpumask_first(alloc_data.hctx->cpumask); + alloc_data.ctx = __blk_mq_get_ctx(q, cpu); - blk_mq_set_alloc_data(&alloc_data, q, flags, ctx, hctx); - rq = __blk_mq_alloc_request(&alloc_data, rw); - if (!rq) { - ret = -EWOULDBLOCK; - goto out_queue_exit; - } - - return rq; + rq = blk_mq_sched_get_request(q, NULL, rw, &alloc_data); -out_queue_exit: + blk_mq_put_ctx(alloc_data.ctx); blk_queue_exit(q); - return ERR_PTR(ret); + + if (!rq) + return ERR_PTR(-EWOULDBLOCK); + + return rq; } EXPORT_SYMBOL_GPL(blk_mq_alloc_request_hctx); -- 2.20.1