[SCSI] 3w-9xxx: use sg buffer copy helper functions

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Adam Radford <linuxraid@amcc.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/3w-9xxx.c b/drivers/scsi/3w-9xxx.c
index b4912d1..fa922f8 100644
--- a/drivers/scsi/3w-9xxx.c
+++ b/drivers/scsi/3w-9xxx.c
@@ -1838,12 +1838,11 @@
 		if (scsi_sg_count(srb)) {
 			if ((scsi_sg_count(srb) == 1) &&
 			    (scsi_bufflen(srb) < TW_MIN_SGL_LENGTH)) {
-				if (srb->sc_data_direction == DMA_TO_DEVICE || srb->sc_data_direction == DMA_BIDIRECTIONAL) {
-					struct scatterlist *sg = scsi_sglist(srb);
-					char *buf = kmap_atomic(sg_page(sg), KM_IRQ0) + sg->offset;
-					memcpy(tw_dev->generic_buffer_virt[request_id], buf, sg->length);
-					kunmap_atomic(buf - sg->offset, KM_IRQ0);
-				}
+				if (srb->sc_data_direction == DMA_TO_DEVICE ||
+				    srb->sc_data_direction == DMA_BIDIRECTIONAL)
+					scsi_sg_copy_to_buffer(srb,
+							       tw_dev->generic_buffer_virt[request_id],
+							       TW_SECTOR_SIZE);
 				command_packet->sg_list[0].address = TW_CPU_TO_SGL(tw_dev->generic_buffer_phys[request_id]);
 				command_packet->sg_list[0].length = cpu_to_le32(TW_MIN_SGL_LENGTH);
 			} else {
@@ -1915,13 +1914,11 @@
 	    (cmd->sc_data_direction == DMA_FROM_DEVICE ||
 	     cmd->sc_data_direction == DMA_BIDIRECTIONAL)) {
 		if (scsi_sg_count(cmd) == 1) {
-			struct scatterlist *sg = scsi_sglist(tw_dev->srb[request_id]);
-			char *buf;
-			unsigned long flags = 0;
+			unsigned long flags;
+			void *buf = tw_dev->generic_buffer_virt[request_id];
+
 			local_irq_save(flags);
-			buf = kmap_atomic(sg_page(sg), KM_IRQ0) + sg->offset;
-			memcpy(buf, tw_dev->generic_buffer_virt[request_id], sg->length);
-			kunmap_atomic(buf - sg->offset, KM_IRQ0);
+			scsi_sg_copy_from_buffer(cmd, buf, TW_SECTOR_SIZE);
 			local_irq_restore(flags);
 		}
 	}