From 50b787f7235efbd074bbdf4315e0cc261d85b4d7 Mon Sep 17 00:00:00 2001 From: "Matthew R. Ochs" Date: Wed, 12 Apr 2017 14:15:02 -0500 Subject: [PATCH] scsi: cxlflash: Remove unnecessary DMA mapping Devices supported by the cxlflash driver are fully coherent and do not require a bus address mapping. Avoid unnecessary path length by using the virtual address and length already present in the scatter-gather entry. Signed-off-by: Matthew R. Ochs Signed-off-by: Uma Krishnan Signed-off-by: Martin K. Petersen --- drivers/scsi/cxlflash/main.c | 15 ++------------- 1 file changed, 2 insertions(+), 13 deletions(-) diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index ebba3c90a242..3c4a83307e6e 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -176,7 +176,6 @@ static void cmd_complete(struct afu_cmd *cmd) dev_dbg_ratelimited(dev, "%s:scp=%p result=%08x ioasc=%08x\n", __func__, scp, scp->result, cmd->sa.ioasc); - scsi_dma_unmap(scp); scp->scsi_done(scp); if (cmd_is_tmf) { @@ -445,7 +444,6 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) struct scatterlist *sg = scsi_sglist(scp); u16 req_flags = SISL_REQ_FLAGS_SUP_UNDERRUN; ulong lock_flags; - int nseg = 0; int rc = 0; dev_dbg_ratelimited(dev, "%s: (scp=%p) %d/%d/%d/%llu " @@ -487,15 +485,8 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) } if (likely(sg)) { - nseg = scsi_dma_map(scp); - if (unlikely(nseg < 0)) { - dev_err(dev, "%s: Fail DMA map\n", __func__); - rc = SCSI_MLQUEUE_HOST_BUSY; - goto out; - } - - cmd->rcb.data_len = sg_dma_len(sg); - cmd->rcb.data_ea = sg_dma_address(sg); + cmd->rcb.data_len = sg->length; + cmd->rcb.data_ea = (uintptr_t)sg_virt(sg); } cmd->scp = scp; @@ -513,8 +504,6 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) memcpy(cmd->rcb.cdb, scp->cmnd, sizeof(cmd->rcb.cdb)); rc = afu->send_cmd(afu, cmd); - if (unlikely(rc)) - scsi_dma_unmap(scp); out: return rc; } -- 2.20.1