scsi: introduce scsi_req_data

This abstracts calling the command_complete callback, reducing churn
in the following patches.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

hw/scsi-bus.c

@@ -495,6 +495,17 @@ static const char *scsi_command_name(uint8_t cmd)
     return names[cmd];
 }
 
+/* Called by the devices when data is ready for the HBA.  The HBA should
+   start a DMA operation to read or fill the device's data buffer.
+   Once it completes, calling one of req->dev->info->read_data or
+   req->dev->info->write_data (depending on the direction of the
+   transfer) will restart I/O.  */
+void scsi_req_data(SCSIRequest *req, int len)
+{
+    trace_scsi_req_data(req->dev->id, req->lun, req->tag, len);
+    req->bus->complete(req->bus, SCSI_REASON_DATA, req->tag, len);
+}
+
 void scsi_req_print(SCSIRequest *req)
 {
     FILE *fp = stderr;

hw/scsi-disk.c

@@ -170,7 +170,7 @@ static void scsi_read_complete(void * opaque, int ret)
     n = r->iov.iov_len / 512;
     r->sector += n;
     r->sector_count -= n;
-    r->req.bus->complete(r->req.bus, SCSI_REASON_DATA, r->req.tag, r->iov.iov_len);
+    scsi_req_data(&r->req, r->iov.iov_len);
 }
 
 
@@ -182,7 +182,7 @@ static void scsi_read_request(SCSIDiskReq *r)
     if (r->sector_count == (uint32_t)-1) {
         DPRINTF("Read buf_len=%zd\n", r->iov.iov_len);
         r->sector_count = 0;
-        r->req.bus->complete(r->req.bus, SCSI_REASON_DATA, r->req.tag, r->iov.iov_len);
+        scsi_req_data(&r->req, r->iov.iov_len);
         return;
     }
     DPRINTF("Read sector_count=%d\n", r->sector_count);
@@ -245,7 +245,7 @@ static int scsi_handle_rw_error(SCSIDiskReq *r, int error, int type)
         vm_stop(VMSTOP_DISKFULL);
     } else {
         if (type == SCSI_REQ_STATUS_RETRY_READ) {
-            r->req.bus->complete(r->req.bus, SCSI_REASON_DATA, r->req.tag, 0);
+            scsi_req_data(&r->req, 0);
         }
         scsi_command_complete(r, CHECK_CONDITION,
                 HARDWARE_ERROR);
@@ -281,7 +281,7 @@ static void scsi_write_complete(void * opaque, int ret)
         }
         r->iov.iov_len = len;
         DPRINTF("Write complete tag=0x%x more=%d\n", r->req.tag, len);
-        r->req.bus->complete(r->req.bus, SCSI_REASON_DATA, r->req.tag, len);
+        scsi_req_data(&r->req, len);
     }
 }
 

hw/scsi-generic.c

@@ -175,7 +175,7 @@ static void scsi_read_complete(void * opaque, int ret)
     if (len == 0) {
         scsi_command_complete(r, 0);
     } else {
-        r->req.bus->complete(r->req.bus, SCSI_REASON_DATA, r->req.tag, len);
+        scsi_req_data(&r->req, len);
     }
 }
 
@@ -212,7 +212,7 @@ static void scsi_read_data(SCSIDevice *d, uint32_t tag)
         DPRINTF("Sense: %d %d %d %d %d %d %d %d\n",
                 r->buf[0], r->buf[1], r->buf[2], r->buf[3],
                 r->buf[4], r->buf[5], r->buf[6], r->buf[7]);
-        r->req.bus->complete(r->req.bus, SCSI_REASON_DATA, r->req.tag, s->senselen);
+        scsi_req_data(&r->req, s->senselen);
         return;
     }
 
@@ -263,7 +263,7 @@ static int scsi_write_data(SCSIDevice *d, uint32_t tag)
 
     if (r->len == 0) {
         r->len = r->buflen;
-        r->req.bus->complete(r->req.bus, SCSI_REASON_DATA, r->req.tag, r->len);
+        scsi_req_data(&r->req, r->len);
         return 0;
     }
 

hw/scsi.h

@@ -105,6 +105,7 @@ void scsi_req_free(SCSIRequest *req);
 
 int scsi_req_parse(SCSIRequest *req, uint8_t *buf);
 void scsi_req_print(SCSIRequest *req);
+void scsi_req_data(SCSIRequest *req, int len);
 void scsi_req_complete(SCSIRequest *req);
 
 #endif

trace-events

@@ -207,6 +207,7 @@ disable usb_set_device_feature(int addr, int feature, int ret) "dev %d, feature
 
 # hw/scsi-bus.c
 disable scsi_req_alloc(int target, int lun, int tag) "target %d lun %d tag %d"
+disable scsi_req_data(int target, int lun, int tag, int len) "target %d lun %d tag %d len %d"
 disable scsi_req_dequeue(int target, int lun, int tag) "target %d lun %d tag %d"
 disable scsi_req_parsed(int target, int lun, int tag, int cmd, int mode, int xfer, uint64_t lba) "target %d lun %d tag %d command %d dir %d length %d lba %"PRIu64""
 disable scsi_req_parse_bad(int target, int lun, int tag, int cmd) "target %d lun %d tag %d command %d"