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 <hch@xxxxxx>
---
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 bf0d71fe243e..3f06e942fb47 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;
--
2.20.1
