[v4,16/24] scsi: introduce scsi_req_get_buf

diff --git a/hw/esp.c b/hw/esp.c
index ced8945..381a8fb 100644
--- a/hw/esp.c
+++ b/hw/esp.c
@@ -419,7 +419,7 @@  static void esp_command_complete(SCSIRequest *req, int reason, uint32_t arg)
     } else {
         DPRINTF("transfer %d/%d\n", s->dma_left, s->ti_size);
         s->async_len = arg;
-        s->async_buf = s->current_dev->info->get_buf(req);
+        s->async_buf = scsi_req_get_buf(req);
         if (s->dma_left) {
             esp_do_dma(s);
         } else if (s->dma_counter != 0 && s->ti_size <= 0) {
diff --git a/hw/lsi53c895a.c b/hw/lsi53c895a.c
index 3d5febb..a6c7c5b 100644
--- a/hw/lsi53c895a.c
+++ b/hw/lsi53c895a.c
@@ -569,7 +569,7 @@  static void lsi_do_dma(LSIState *s, int out)
     s->dnad += count;
     s->dbc -= count;
      if (s->current->dma_buf == NULL) {
-        s->current->dma_buf = dev->info->get_buf(s->current->req);
+        s->current->dma_buf = scsi_req_get_buf(s->current->req);
     }
     /* ??? Set SFBR to first data byte.  */
     if (out) {
diff --git a/hw/scsi-bus.c b/hw/scsi-bus.c
index 4541877..c6b7ee5 100644
--- a/hw/scsi-bus.c
+++ b/hw/scsi-bus.c
@@ -151,6 +151,11 @@  SCSIRequest *scsi_req_new(SCSIDevice *d, uint32_t tag, uint32_t lun)
     return d->info->alloc_req(d, tag, lun);
 }
 
+uint8_t *scsi_req_get_buf(SCSIRequest *req)
+{
+    return req->dev->info->get_buf(req);
+}
+
 int32_t scsi_req_enqueue(SCSIRequest *req, uint8_t *buf)
 {
     assert(!req->enqueued);
diff --git a/hw/scsi.h b/hw/scsi.h
index 9038812..a4bdede 100644
--- a/hw/scsi.h
+++ b/hw/scsi.h
@@ -154,6 +154,7 @@  void scsi_req_print(SCSIRequest *req);
 void scsi_req_continue(SCSIRequest *req);
 void scsi_req_data(SCSIRequest *req, int len);
 void scsi_req_complete(SCSIRequest *req);
+uint8_t *scsi_req_get_buf(SCSIRequest *req);
 void scsi_req_abort(SCSIRequest *req, int status);
 void scsi_req_cancel(SCSIRequest *req);
 void scsi_device_purge_requests(SCSIDevice *sdev);
diff --git a/hw/spapr_vscsi.c b/hw/spapr_vscsi.c
index 3f65a87..29ac8ef 100644
--- a/hw/spapr_vscsi.c
+++ b/hw/spapr_vscsi.c
@@ -74,7 +74,6 @@  typedef struct vscsi_req {
     union viosrp_iu         iu;
 
     /* SCSI request tracking */
-    SCSIDevice              *sdev;
     SCSIRequest             *sreq;
     uint32_t                qtag; /* qemu tag != srp tag */
     int                     lun;
@@ -476,7 +475,6 @@  static void vscsi_command_complete(SCSIRequest *sreq, int reason, uint32_t arg)
 {
     VSCSIState *s = DO_UPCAST(VSCSIState, vdev.qdev, sreq->bus->qbus.parent);
     vscsi_req *req = vscsi_find_req(s, sreq);
-    SCSIDevice *sdev;
     uint8_t *buf;
     int32_t res_in = 0, res_out = 0;
     int len, rc = 0;
@@ -487,7 +485,6 @@  static void vscsi_command_complete(SCSIRequest *sreq, int reason, uint32_t arg)
         fprintf(stderr, "VSCSI: Can't find request for tag 0x%x\n", sreq->tag);
         return;
     }
-    sdev = req->sdev;
 
     if (req->sensing) {
         if (reason == SCSI_REASON_DONE) {
@@ -495,7 +492,7 @@  static void vscsi_command_complete(SCSIRequest *sreq, int reason, uint32_t arg)
             vscsi_send_rsp(s, req, CHECK_CONDITION, 0, 0);
             vscsi_put_req(s, req);
         } else {
-            uint8_t *buf = sdev->info->get_buf(sreq);
+            uint8_t *buf = scsi_req_get_buf(sreq);
 
             len = MIN(arg, SCSI_SENSE_BUF_SIZE);
             dprintf("VSCSI: Sense data, %d bytes:\n", len);
@@ -539,7 +536,7 @@  static void vscsi_command_complete(SCSIRequest *sreq, int reason, uint32_t arg)
      * to write for writes (ie, how much is to be DMA'd)
      */
     if (arg) {
-        buf = sdev->info->get_buf(sreq);
+        buf = scsi_req_get_buf(sreq);
         rc = vscsi_srp_transfer_data(s, req, req->writing, buf, arg);
     }
     if (rc < 0) {
@@ -646,7 +643,6 @@  static int vscsi_queue_cmd(VSCSIState *s, vscsi_req *req)
         } return 1;
     }
 
-    req->sdev = sdev;
     req->lun = lun;
     req->sreq = scsi_req_new(sdev, req->qtag, lun);
     n = scsi_req_enqueue(req->sreq, srp->cmd.cdb);
diff --git a/hw/usb-msd.c b/hw/usb-msd.c
index 5f84256..27a37fa 100644
--- a/hw/usb-msd.c
+++ b/hw/usb-msd.c
@@ -247,7 +247,7 @@  static void usb_msd_command_complete(SCSIRequest *req, int reason, uint32_t arg)
     }
     assert((s->mode == USB_MSDM_DATAOUT) == (req->cmd.mode == SCSI_XFER_TO_DEV));
     s->scsi_len = arg;
-    s->scsi_buf = s->scsi_dev->info->get_buf(req);
+    s->scsi_buf = scsi_req_get_buf(req);
     if (p) {
         usb_msd_copy_data(s);
         if (s->usb_len == 0) {