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>
This commit is contained in:
Matthew R. Ochs 2016-11-28 18:43:01 -06:00 committed by Martin K. Petersen
parent d4ace35166
commit 9d89326c66

View File

@ -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;
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.scp = scp;
cmd->parent = afu;
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;
req_flags |= SISL_REQ_FLAGS_HOST_WRITE;
cmd->rcb.req_flags = (SISL_REQ_FLAGS_PORT_LUN_ID |
SISL_REQ_FLAGS_SUP_UNDERRUN | lflag);
/* 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;
}
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);
}
/* 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);