From f4829a9b7a61e159367350008a608b062c4f6840 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sun, 27 Sep 2015 21:01:50 +0200 Subject: blk-mq: fix racy updates of rq->errors blk_mq_complete_request may be a no-op if the request has already been completed by others means (e.g. a timeout or cancellation), but currently drivers have to set rq->errors before calling blk_mq_complete_request, which might leave us with the wrong error value. Add an error parameter to blk_mq_complete_request so that we can defer setting rq->errors until we known we won the race to complete the request. Signed-off-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Jens Axboe --- drivers/block/nvme-core.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) (limited to 'drivers/block/nvme-core.c') diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c index 30758bdf69ea..6f04771f1019 100644 --- a/drivers/block/nvme-core.c +++ b/drivers/block/nvme-core.c @@ -618,16 +618,15 @@ static void req_completion(struct nvme_queue *nvmeq, void *ctx, spin_unlock_irqrestore(req->q->queue_lock, flags); return; } + if (req->cmd_type == REQ_TYPE_DRV_PRIV) { if (cmd_rq->ctx == CMD_CTX_CANCELLED) - req->errors = -EINTR; - else - req->errors = status; + status = -EINTR; } else { - req->errors = nvme_error_status(status); + status = nvme_error_status(status); } - } else - req->errors = 0; + } + if (req->cmd_type == REQ_TYPE_DRV_PRIV) { u32 result = le32_to_cpup(&cqe->result); req->special = (void *)(uintptr_t)result; @@ -650,7 +649,7 @@ static void req_completion(struct nvme_queue *nvmeq, void *ctx, } nvme_free_iod(nvmeq->dev, iod); - blk_mq_complete_request(req); + blk_mq_complete_request(req, status); } /* length is in bytes. gfp flags indicates whether we may sleep. */ @@ -863,8 +862,7 @@ static int nvme_queue_rq(struct blk_mq_hw_ctx *hctx, if (ns && ns->ms && !blk_integrity_rq(req)) { if (!(ns->pi_type && ns->ms == 8) && req->cmd_type != REQ_TYPE_DRV_PRIV) { - req->errors = -EFAULT; - blk_mq_complete_request(req); + blk_mq_complete_request(req, -EFAULT); return BLK_MQ_RQ_QUEUE_OK; } } -- cgit v1.2.3