From cfa27356f835dc7755192e7b941d4f4851acbcc7 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 30 Jan 2020 19:40:24 +0100 Subject: [PATCH] nvme-pci: remove nvmeq->tags There is no real need to have a pointer to the tagset in struct nvme_queue, as we only need it in a single place, and that place can derive the used tagset from the device and qid trivially. This fixes a problem with stale pointer exposure when tagsets are reset, and also shrinks the nvme_queue structure. It also matches what most other transports have done since day 1. Reported-by: Edmund Nadolski Signed-off-by: Christoph Hellwig Signed-off-by: Keith Busch --- drivers/nvme/host/pci.c | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 365a2dd..da392b5 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -167,7 +167,6 @@ struct nvme_queue { /* only used for poll queues: */ spinlock_t cq_poll_lock ____cacheline_aligned_in_smp; volatile struct nvme_completion *cqes; - struct blk_mq_tags **tags; dma_addr_t sq_dma_addr; dma_addr_t cq_dma_addr; u32 __iomem *q_db; @@ -376,29 +375,17 @@ static int nvme_admin_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, WARN_ON(hctx_idx != 0); WARN_ON(dev->admin_tagset.tags[0] != hctx->tags); - WARN_ON(nvmeq->tags); hctx->driver_data = nvmeq; - nvmeq->tags = &dev->admin_tagset.tags[0]; return 0; } -static void nvme_admin_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) -{ - struct nvme_queue *nvmeq = hctx->driver_data; - - nvmeq->tags = NULL; -} - static int nvme_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, unsigned int hctx_idx) { struct nvme_dev *dev = data; struct nvme_queue *nvmeq = &dev->queues[hctx_idx + 1]; - if (!nvmeq->tags) - nvmeq->tags = &dev->tagset.tags[hctx_idx]; - WARN_ON(dev->tagset.tags[hctx_idx] != hctx->tags); hctx->driver_data = nvmeq; return 0; @@ -948,6 +935,13 @@ static inline void nvme_ring_cq_doorbell(struct nvme_queue *nvmeq) writel(head, nvmeq->q_db + nvmeq->dev->db_stride); } +static inline struct blk_mq_tags *nvme_queue_tagset(struct nvme_queue *nvmeq) +{ + if (!nvmeq->qid) + return nvmeq->dev->admin_tagset.tags[0]; + return nvmeq->dev->tagset.tags[nvmeq->qid - 1]; +} + static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx) { volatile struct nvme_completion *cqe = &nvmeq->cqes[idx]; @@ -972,7 +966,7 @@ static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx) return; } - req = blk_mq_tag_to_rq(*nvmeq->tags, cqe->command_id); + req = blk_mq_tag_to_rq(nvme_queue_tagset(nvmeq), cqe->command_id); trace_nvme_sq(req, cqe->sq_head, nvmeq->sq_tail); nvme_end_request(req, cqe->status, cqe->result); } @@ -1572,7 +1566,6 @@ static const struct blk_mq_ops nvme_mq_admin_ops = { .queue_rq = nvme_queue_rq, .complete = nvme_pci_complete_rq, .init_hctx = nvme_admin_init_hctx, - .exit_hctx = nvme_admin_exit_hctx, .init_request = nvme_init_request, .timeout = nvme_timeout, }; -- 2.7.4