From 9b048119a153590b934ef49aae309b723587f527 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sun, 3 Mar 2019 08:04:01 -0700 Subject: [PATCH] nvme-pci: remove nvme_init_iod nvme_init_iod should really be split into two parts: initialize a few general iod fields, which can easily be done at the beginning of nvme_queue_rq, and allocating the scatterlist if needed, which logically belongs into nvme_map_data with the code making use of it. Signed-off-by: Christoph Hellwig Reviewed-by: Keith Busch Reviewed-by: Sagi Grimberg Reviewed-by: Chaitanya Kulkarni --- drivers/nvme/host/pci.c | 56 +++++++++++++++++++------------------------------ 1 file changed, 22 insertions(+), 34 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 0cba927..2102a10 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -208,10 +208,10 @@ struct nvme_queue { }; /* - * The nvme_iod describes the data in an I/O, including the list of PRP - * entries. You can't see it in this data structure because C doesn't let - * me express that. Use nvme_init_iod to ensure there's enough space - * allocated to store the PRP list. + * The nvme_iod describes the data in an I/O. + * + * The sg pointer contains the list of PRP/SGL chunk allocations in addition + * to the actual struct scatterlist. */ struct nvme_iod { struct nvme_request req; @@ -583,29 +583,6 @@ static inline bool nvme_pci_use_sgls(struct nvme_dev *dev, struct request *req) return true; } -static blk_status_t nvme_init_iod(struct request *rq, struct nvme_dev *dev) -{ - struct nvme_iod *iod = blk_mq_rq_to_pdu(rq); - int nseg = blk_rq_nr_phys_segments(rq); - unsigned int size = blk_rq_payload_bytes(rq); - - iod->use_sgl = nvme_pci_use_sgls(dev, rq); - - if (nseg > NVME_INT_PAGES || size > NVME_INT_BYTES(dev)) { - iod->sg = mempool_alloc(dev->iod_mempool, GFP_ATOMIC); - if (!iod->sg) - return BLK_STS_RESOURCE; - } else { - iod->sg = iod->inline_sg; - } - - iod->aborted = 0; - iod->npages = -1; - iod->nents = 0; - - return BLK_STS_OK; -} - static void nvme_free_iod(struct nvme_dev *dev, struct request *req) { struct nvme_iod *iod = blk_mq_rq_to_pdu(req); @@ -837,6 +814,17 @@ static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req, blk_status_t ret = BLK_STS_IOERR; int nr_mapped; + if (blk_rq_payload_bytes(req) > NVME_INT_BYTES(dev) || + blk_rq_nr_phys_segments(req) > NVME_INT_PAGES) { + iod->sg = mempool_alloc(dev->iod_mempool, GFP_ATOMIC); + if (!iod->sg) + return BLK_STS_RESOURCE; + } else { + iod->sg = iod->inline_sg; + } + + iod->use_sgl = nvme_pci_use_sgls(dev, req); + sg_init_table(iod->sg, blk_rq_nr_phys_segments(req)); iod->nents = blk_rq_map_sg(q, req, iod->sg); if (!iod->nents) @@ -881,6 +869,7 @@ static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req, out_unmap: dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir); out: + nvme_free_iod(dev, req); return ret; } @@ -913,9 +902,14 @@ static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx, struct nvme_queue *nvmeq = hctx->driver_data; struct nvme_dev *dev = nvmeq->dev; struct request *req = bd->rq; + struct nvme_iod *iod = blk_mq_rq_to_pdu(req); struct nvme_command cmnd; blk_status_t ret; + iod->aborted = 0; + iod->npages = -1; + iod->nents = 0; + /* * We should not need to do this, but we're still using this to * ensure we can drain requests on a dying queue. @@ -927,21 +921,15 @@ static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx, if (ret) return ret; - ret = nvme_init_iod(req, dev); - if (ret) - goto out_free_cmd; - if (blk_rq_nr_phys_segments(req)) { ret = nvme_map_data(dev, req, &cmnd); if (ret) - goto out_cleanup_iod; + goto out_free_cmd; } blk_mq_start_request(req); nvme_submit_cmd(nvmeq, &cmnd, bd->last); return BLK_STS_OK; -out_cleanup_iod: - nvme_free_iod(dev, req); out_free_cmd: nvme_cleanup_cmd(req); return ret; -- 2.7.4