scsi: cxlflash: Cleanup queuecommand()

The queuecommand routine is disorganized where it populates the
private command and also contains some logic/statements that are
not needed given that cxlflash devices do not (and likely never
will) support scatter-gather.

Restructure the code to remove the unnecessary logic and create an
organized flow:

	handle state -> DMA map -> populate command -> send command

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index b7636993a097c24d3063fdfa4a1715ecc9dd5390..4e70c9a30afc97a59c832c02c7149705ac50112b 100644 (file)
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -388,11 +388,11 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp)
        struct afu *afu = cfg->afu;
        struct device *dev = &cfg->dev->dev;
        struct afu_cmd *cmd = sc_to_afucz(scp);
+       struct scatterlist *sg = scsi_sglist(scp);
        u32 port_sel = scp->device->channel + 1;
-       int nseg, i, ncount;
-       struct scatterlist *sg;
+       u16 req_flags = SISL_REQ_FLAGS_SUP_UNDERRUN;
        ulong lock_flags;
-       short lflag = 0;
+       int nseg = 0;
        int rc = 0;
        int kref_got = 0;
 
@@ -435,45 +435,35 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp)
        kref_get(&cfg->afu->mapcount);
        kref_got = 1;
 
-       cmd->rcb.ctx_id = afu->ctx_hndl;
-       cmd->rcb.msi = SISL_MSI_RRQ_UPDATED;
-       cmd->rcb.port_sel = port_sel;
-       cmd->rcb.lun_id = lun_to_lunid(scp->device->lun);
-
-       if (scp->sc_data_direction == DMA_TO_DEVICE)
-               lflag = SISL_REQ_FLAGS_HOST_WRITE;
-       else
-               lflag = SISL_REQ_FLAGS_HOST_READ;
+       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.req_flags = (SISL_REQ_FLAGS_PORT_LUN_ID |
-                             SISL_REQ_FLAGS_SUP_UNDERRUN | lflag);
+               cmd->rcb.data_len = sg_dma_len(sg);
+               cmd->rcb.data_ea = sg_dma_address(sg);
+       }
 
-       /* Stash the scp in the reserved field, for reuse during interrupt */
        cmd->rcb.scp = scp;
        cmd->parent = afu;
 
-       nseg = scsi_dma_map(scp);
-       if (unlikely(nseg < 0)) {
-               dev_err(dev, "%s: Fail DMA map! nseg=%d\n",
-                       __func__, nseg);
-               rc = SCSI_MLQUEUE_HOST_BUSY;
-               goto out;
-       }
+       cmd->rcb.ctx_id = afu->ctx_hndl;
+       cmd->rcb.msi = SISL_MSI_RRQ_UPDATED;
+       cmd->rcb.port_sel = port_sel;
+       cmd->rcb.lun_id = lun_to_lunid(scp->device->lun);
 
-       ncount = scsi_sg_count(scp);
-       scsi_for_each_sg(scp, sg, ncount, i) {
-               cmd->rcb.data_len = sg_dma_len(sg);
-               cmd->rcb.data_ea = sg_dma_address(sg);
-       }
+       if (scp->sc_data_direction == DMA_TO_DEVICE)
+               req_flags |= SISL_REQ_FLAGS_HOST_WRITE;
 
-       /* Copy the CDB from the scsi_cmnd passed in */
+       cmd->rcb.req_flags = req_flags;
        memcpy(cmd->rcb.cdb, scp->cmnd, sizeof(cmd->rcb.cdb));
 
-       /* Send the command */
        rc = send_cmd(afu, cmd);
        if (unlikely(rc))
                scsi_dma_unmap(scp);
-
 out:
        if (kref_got)
                kref_put(&afu->mapcount, afu_unmap);