pseries: savevm support for PAPR virtual SCSI

This patch adds the necessary support for saving the state of the PAPR VIO
virtual SCSI device. This also saves and restores active SCSI requests.

[aik: implemented vscsi_req save/restore]
Signed-off-by: Alexey Kardashevskiy <[email protected]>
Message-id: [email protected]
Cc: David Gibson <[email protected]>
Signed-off-by: Anthony Liguori <[email protected]>

hw/scsi/spapr_vscsi.c

@@ -578,6 +578,69 @@ static void vscsi_request_cancelled(SCSIRequest *sreq)
     vscsi_put_req(req);
 }
 
+static const VMStateDescription vmstate_spapr_vscsi_req = {
+    .name = "spapr_vscsi_req",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields      = (VMStateField []) {
+        VMSTATE_BUFFER(crq.raw, vscsi_req),
+        VMSTATE_BUFFER(iu.srp.reserved, vscsi_req),
+        VMSTATE_UINT32(qtag, vscsi_req),
+        VMSTATE_BOOL(active, vscsi_req),
+        VMSTATE_UINT32(data_len, vscsi_req),
+        VMSTATE_BOOL(writing, vscsi_req),
+        VMSTATE_UINT32(senselen, vscsi_req),
+        VMSTATE_BUFFER(sense, vscsi_req),
+        VMSTATE_UINT8(dma_fmt, vscsi_req),
+        VMSTATE_UINT16(local_desc, vscsi_req),
+        VMSTATE_UINT16(total_desc, vscsi_req),
+        VMSTATE_UINT16(cdb_offset, vscsi_req),
+      /*Restart SCSI request from the beginning for now */
+      /*VMSTATE_UINT16(cur_desc_num, vscsi_req),
+        VMSTATE_UINT16(cur_desc_offset, vscsi_req),*/
+        VMSTATE_END_OF_LIST()
+    },
+};
+
+static void vscsi_save_request(QEMUFile *f, SCSIRequest *sreq)
+{
+    vscsi_req *req = sreq->hba_private;
+    assert(req->active);
+
+    vmstate_save_state(f, &vmstate_spapr_vscsi_req, req);
+
+    dprintf("VSCSI: saving tag=%u, current desc#%d, offset=%x\n",
+            req->qtag, req->cur_desc_num, req->cur_desc_offset);
+}
+
+static void *vscsi_load_request(QEMUFile *f, SCSIRequest *sreq)
+{
+    SCSIBus *bus = sreq->bus;
+    VSCSIState *s = VIO_SPAPR_VSCSI_DEVICE(bus->qbus.parent);
+    vscsi_req *req;
+    int rc;
+
+    assert(sreq->tag < VSCSI_REQ_LIMIT);
+    req = &s->reqs[sreq->tag];
+    assert(!req->active);
+
+    memset(req, 0, sizeof(*req));
+    rc = vmstate_load_state(f, &vmstate_spapr_vscsi_req, req, 1);
+    if (rc) {
+        fprintf(stderr, "VSCSI: failed loading request tag#%u\n", sreq->tag);
+        return NULL;
+    }
+    assert(req->active);
+
+    req->sreq = scsi_req_ref(sreq);
+
+    dprintf("VSCSI: restoring tag=%u, current desc#%d, offset=%x\n",
+            req->qtag, req->cur_desc_num, req->cur_desc_offset);
+
+    return req;
+}
+
 static void vscsi_process_login(VSCSIState *s, vscsi_req *req)
 {
     union viosrp_iu *iu = &req->iu;
@@ -932,7 +995,9 @@ static const struct SCSIBusInfo vscsi_scsi_info = {
 
     .transfer_data = vscsi_transfer_data,
     .complete = vscsi_command_complete,
-    .cancel = vscsi_request_cancelled
+    .cancel = vscsi_request_cancelled,
+    .save_request = vscsi_save_request,
+    .load_request = vscsi_load_request,
 };
 
 static void spapr_vscsi_reset(VIOsPAPRDevice *dev)
@@ -996,6 +1061,20 @@ static Property spapr_vscsi_properties[] = {
     DEFINE_PROP_END_OF_LIST(),
 };
 
+static const VMStateDescription vmstate_spapr_vscsi = {
+    .name = "spapr_vscsi",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields      = (VMStateField []) {
+        VMSTATE_SPAPR_VIO(vdev, VSCSIState),
+        /* VSCSI state */
+        /* ???? */
+
+        VMSTATE_END_OF_LIST()
+    },
+};
+
 static void spapr_vscsi_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
@@ -1010,6 +1089,7 @@ static void spapr_vscsi_class_init(ObjectClass *klass, void *data)
     k->signal_mask = 0x00000001;
     dc->props = spapr_vscsi_properties;
     k->rtce_window_size = 0x10000000;
+    dc->vmsd = &vmstate_spapr_vscsi;
 }
 
 static const TypeInfo spapr_vscsi_info = {