[PATCH 4/4] nvmet-fc: Use new SGL alloc/free helper for requests

Logan Gunthorpe
2018-03-29T16:07:33Z

Use the new helpers introduced earlier to allocate the SGLs for
the request.

To do this, we drop the appearantly redundant data_sg and data_sg_cnt
members as they are identical to the existing req.sg and req.sg_cnt.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Cc: James Smart <james.smart@broadcom.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
---
drivers/nvme/target/fc.c | 38 +++++++++++---------------------------
1 file changed, 11 insertions(+), 27 deletions(-)

diff --git a/drivers/nvme/target/fc.c b/drivers/nvme/target/fc.c
index 9f2f8ab83158..00135ff7d1c2 100644
--- a/drivers/nvme/target/fc.c
+++ b/drivers/nvme/target/fc.c
@@ -74,8 +74,6 @@ struct nvmet_fc_fcp_iod {
struct nvme_fc_cmd_iu cmdiubuf;
struct nvme_fc_ersp_iu rspiubuf;
dma_addr_t rspdma;
- struct scatterlist *data_sg;
- int data_sg_cnt;
u32 offset;
enum nvmet_fcp_datadir io_dir;
bool active;
@@ -1696,43 +1694,34 @@ EXPORT_SYMBOL_GPL(nvmet_fc_rcv_ls_req);
static int
nvmet_fc_alloc_tgt_pgs(struct nvmet_fc_fcp_iod *fod)
{
- struct scatterlist *sg;
- unsigned int nent;
int ret;

- sg = sgl_alloc(fod->req.transfer_len, GFP_KERNEL, &nent);
- if (!sg)
- goto out;
+ ret = nvmet_req_alloc_sgl(&fod->req, &fod->queue->nvme_sq);
+ if (ret < 0)
+ return NVME_SC_INTERNAL;

- fod->data_sg = sg;
- fod->data_sg_cnt = nent;
- ret = fc_dma_map_sg(fod->tgtport->dev, sg, nent,
+ ret = fc_dma_map_sg(fod->tgtport->dev, fod->req.sg, fod->req.sg_cnt,
((fod->io_dir == NVMET_FCP_WRITE) ?
DMA_FROM_DEVICE : DMA_TO_DEVICE));
/* note: write from initiator perspective */
if (!ret)
- goto out;
+ return NVME_SC_INTERNAL;

return 0;
-
-out:
- return NVME_SC_INTERNAL;
}

static void
nvmet_fc_free_tgt_pgs(struct nvmet_fc_fcp_iod *fod)
{
- if (!fod->data_sg || !fod->data_sg_cnt)
+ if (!fod->req.sg || !fod->req.sg_cnt)
return;

- fc_dma_unmap_sg(fod->tgtport->dev, fod->data_sg, fod->data_sg_cnt,
+ fc_dma_unmap_sg(fod->tgtport->dev, fod->req.sg, fod->req.sg_cnt,
((fod->io_dir == NVMET_FCP_WRITE) ?
DMA_FROM_DEVICE : DMA_TO_DEVICE));
- sgl_free(fod->data_sg);
- fod->data_sg = NULL;
- fod->data_sg_cnt = 0;
-}

+ nvmet_req_free_sgl(&fod->req);
+}

static bool
queue_90percent_full(struct nvmet_fc_tgt_queue *q, u32 sqhd)
@@ -1871,7 +1860,7 @@ nvmet_fc_transfer_fcp_data(struct nvmet_fc_tgtport *tgtport,
fcpreq->fcp_error = 0;
fcpreq->rsplen = 0;

- fcpreq->sg = &fod->data_sg[fod->offset / PAGE_SIZE];
+ fcpreq->sg = &fod->req.sg[fod->offset / PAGE_SIZE];
fcpreq->sg_cnt = DIV_ROUND_UP(tlen, PAGE_SIZE);

/*
@@ -2083,7 +2072,7 @@ __nvmet_fc_fcp_nvme_cmd_done(struct nvmet_fc_tgtport *tgtport,
* There may be a status where data still was intended to
* be moved
*/
- if ((fod->io_dir == NVMET_FCP_READ) && (fod->data_sg_cnt)) {
+ if ((fod->io_dir == NVMET_FCP_READ) && (fod->req.sg_cnt)) {
/* push the data over before sending rsp */
nvmet_fc_transfer_fcp_data(tgtport, fod,
NVMET_FCOP_READDATA);
@@ -2153,9 +2142,6 @@ nvmet_fc_handle_fcp_rqst(struct nvmet_fc_tgtport *tgtport,
/* clear any response payload */
memset(&fod->rspiubuf, 0, sizeof(fod->rspiubuf));

- fod->data_sg = NULL;
- fod->data_sg_cnt = 0;
-
ret = nvmet_req_init(&fod->req,
&fod->queue->nvme_cq,
&fod->queue->nvme_sq,
@@ -2178,8 +2164,6 @@ nvmet_fc_handle_fcp_rqst(struct nvmet_fc_tgtport *tgtport,
return;
}
}
- fod->req.sg = fod->data_sg;
- fod->req.sg_cnt = fod->data_sg_cnt;
fod->offset = 0;

if (fod->io_dir == NVMET_FCP_WRITE) {
--
2.11.0