scsi: do not call send_command directly

Move the common part of scsi-disk.c and scsi-generic.c to the SCSI layer.

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

hw/esp.c

@@ -245,7 +245,7 @@ static void do_busid_cmd(ESPState *s, uint8_t *buf, uint8_t busid)
     DPRINTF("do_busid_cmd: busid 0x%x\n", busid);
     lun = busid & 7;
     s->current_req = s->current_dev->info->alloc_req(s->current_dev, 0, lun);
-    datalen = s->current_dev->info->send_command(s->current_req, buf);
+    datalen = scsi_req_enqueue(s->current_req, buf);
     s->ti_size = datalen;
     if (datalen != 0) {
         s->rregs[ESP_RSTAT] = STAT_TC;

hw/lsi53c895a.c

@@ -791,7 +791,7 @@ static void lsi_do_command(LSIState *s)
     s->current->req = dev->info->alloc_req(dev, s->current->tag,
                                            s->current_lun);
 
-    n = dev->info->send_command(s->current->req, buf);
+    n = scsi_req_enqueue(s->current->req, buf);
     if (n > 0) {
         lsi_set_phase(s, PHASE_DI);
         dev->info->read_data(s->current->req);

hw/scsi-bus.c

@@ -146,12 +146,19 @@ SCSIRequest *scsi_req_alloc(size_t size, SCSIDevice *d, uint32_t tag, uint32_t l
     return req;
 }
 
-void scsi_req_enqueue(SCSIRequest *req)
+int32_t scsi_req_enqueue(SCSIRequest *req, uint8_t *buf)
 {
+    int32_t rc;
+
     assert(!req->enqueued);
     scsi_req_ref(req);
     req->enqueued = true;
     QTAILQ_INSERT_TAIL(&req->dev->requests, req, next);
+
+    scsi_req_ref(req);
+    rc = req->dev->info->send_command(req, buf);
+    scsi_req_unref(req);
+    return rc;
 }
 
 static void scsi_req_dequeue(SCSIRequest *req)

hw/scsi-disk.c

@@ -984,7 +984,6 @@ static int32_t scsi_send_command(SCSIRequest *req, uint8_t *buf)
     uint8_t *outbuf;
     int rc;
 
-    scsi_req_enqueue(req);
     command = buf[0];
     outbuf = (uint8_t *)r->iov.iov_base;
     is_write = 0;

hw/scsi-generic.c

@@ -320,7 +320,6 @@ static int32_t scsi_send_command(SCSIRequest *req, uint8_t *cmd)
     SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
     int ret;
 
-    scsi_req_enqueue(req);
     if (cmd[0] != REQUEST_SENSE &&
         (req->lun != s->lun || (cmd[1] >> 5) != s->lun)) {
         DPRINTF("Unimplemented LUN %d\n", req->lun ? req->lun : cmd[1] >> 5);

hw/scsi.h

@@ -143,7 +143,7 @@ int scsi_build_sense(SCSISense sense, uint8_t *buf, int len, int fixed);
 int scsi_sense_valid(SCSISense sense);
 
 SCSIRequest *scsi_req_alloc(size_t size, SCSIDevice *d, uint32_t tag, uint32_t lun);
-void scsi_req_enqueue(SCSIRequest *req);
+int32_t scsi_req_enqueue(SCSIRequest *req, uint8_t *buf);
 void scsi_req_free(SCSIRequest *req);
 SCSIRequest *scsi_req_ref(SCSIRequest *req);
 void scsi_req_unref(SCSIRequest *req);

hw/spapr_vscsi.c

@@ -459,7 +459,7 @@ static void vscsi_send_request_sense(VSCSIState *s, vscsi_req *req)
     cdb[4] = 96;
     cdb[5] = 0;
     req->sensing = 1;
-    n = sdev->info->send_command(req->sreq, cdb);
+    n = scsi_req_enqueue(req->sreq, cdb);
     dprintf("VSCSI: Queued request sense tag 0x%x\n", req->qtag);
     if (n < 0) {
         fprintf(stderr, "VSCSI: REQUEST_SENSE wants write data !?!?!?\n");
@@ -654,7 +654,7 @@ static int vscsi_queue_cmd(VSCSIState *s, vscsi_req *req)
     req->sdev = sdev;
     req->lun = lun;
     req->sreq = sdev->info->alloc_req(sdev, req->qtag, lun);
-    n = sdev->info->send_command(req->sreq, srp->cmd.cdb);
+    n = scsi_req_enqueue(req->sreq, srp->cmd.cdb);
 
     dprintf("VSCSI: Queued command tag 0x%x CMD 0x%x ID %d LUN %d ret: %d\n",
             req->qtag, srp->cmd.cdb[0], id, lun, n);

hw/usb-msd.c

@@ -378,7 +378,7 @@ static int usb_msd_handle_data(USBDevice *dev, USBPacket *p)
             s->residue = 0;
             s->scsi_len = 0;
             s->req = s->scsi_dev->info->alloc_req(s->scsi_dev, s->tag, 0);
-            s->scsi_dev->info->send_command(s->req, cbw.cmd);
+            scsi_req_enqueue(s->req, cbw.cmd);
             /* ??? Should check that USB and SCSI data transfer
                directions match.  */
             if (s->residue == 0) {