scsi: pmcraid: don't allocate a dma coherent buffer for sense data

We can just dma map the sense buffer passed with the scsi command,
and that gets us out of the nasty business of doing dma coherent
allocations from irq context.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/pmcraid.c

@@ -846,16 +846,9 @@ static void pmcraid_erp_done(struct pmcraid_cmd *cmd)
 			    cmd->ioa_cb->ioarcb.cdb[0], ioasc);
 	}
 
-	/* if we had allocated sense buffers for request sense, copy the sense
-	 * release the buffers
-	 */
-	if (cmd->sense_buffer != NULL) {
-		memcpy(scsi_cmd->sense_buffer,
-		       cmd->sense_buffer,
-		       SCSI_SENSE_BUFFERSIZE);
-		pci_free_consistent(pinstance->pdev,
-				    SCSI_SENSE_BUFFERSIZE,
-				    cmd->sense_buffer, cmd->sense_buffer_dma);
+	if (cmd->sense_buffer) {
+		dma_unmap_single(&pinstance->pdev->dev, cmd->sense_buffer_dma,
+				 SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
 		cmd->sense_buffer = NULL;
 		cmd->sense_buffer_dma = 0;
 	}
@@ -2444,13 +2437,12 @@ static void pmcraid_request_sense(struct pmcraid_cmd *cmd)
 {
 	struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
 	struct pmcraid_ioadl_desc *ioadl = ioarcb->add_data.u.ioadl;
+	struct device *dev = &cmd->drv_inst->pdev->dev;
 
-	/* allocate DMAable memory for sense buffers */
-	cmd->sense_buffer = pci_alloc_consistent(cmd->drv_inst->pdev,
-						 SCSI_SENSE_BUFFERSIZE,
-						 &cmd->sense_buffer_dma);
-
-	if (cmd->sense_buffer == NULL) {
+	cmd->sense_buffer = cmd->scsi_cmd->sense_buffer;
+	cmd->sense_buffer_dma = dma_map_single(dev, cmd->sense_buffer,
+			SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
+	if (dma_mapping_error(dev, cmd->sense_buffer_dma)) {
 		pmcraid_err
 			("couldn't allocate sense buffer for request sense\n");
 		pmcraid_erp_done(cmd);