s390x/css: use ccw data stream

Replace direct access which implicitly assumes no IDA
or MIDA with the new ccw data stream interface which should
cope with these transparently in the future.

Note that checking the return code for ccw_dstream_* will be
done in a follow-on patch.
Signed-off-by: NHalil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: NDong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Reviewed-by: NPierre Morel <pmorel@linux.vnet.ibm.com>
Message-Id: <20170921180841.24490-3-pasic@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

hw/s390x/css.c

@@ -894,6 +894,7 @@ static int css_interpret_ccw(SubchDev *sch, hwaddr ccw_addr,
     }
 
     /* Look at the command. */
+    ccw_dstream_init(&sch->cds, &ccw, &(sch->orb));
     switch (ccw.cmd_code) {
     case CCW_CMD_NOOP:
         /* Nothing to do. */
@@ -907,8 +908,8 @@ static int css_interpret_ccw(SubchDev *sch, hwaddr ccw_addr,
             }
         }
         len = MIN(ccw.count, sizeof(sch->sense_data));
-        cpu_physical_memory_write(ccw.cda, sch->sense_data, len);
-        sch->curr_status.scsw.count = ccw.count - len;
+        ccw_dstream_write_buf(&sch->cds, sch->sense_data, len);
+        sch->curr_status.scsw.count = ccw_dstream_residual_count(&sch->cds);
         memset(sch->sense_data, 0, sizeof(sch->sense_data));
         ret = 0;
         break;
@@ -934,8 +935,8 @@ static int css_interpret_ccw(SubchDev *sch, hwaddr ccw_addr,
         } else {
             sense_id.reserved = 0;
         }
-        cpu_physical_memory_write(ccw.cda, &sense_id, len);
-        sch->curr_status.scsw.count = ccw.count - len;
+        ccw_dstream_write_buf(&sch->cds, &sense_id, len);
+        sch->curr_status.scsw.count = ccw_dstream_residual_count(&sch->cds);
         ret = 0;
         break;
     }