[RFC PATCH 08/12] vdpa: add vhost_vdpa_svq_start

["Eugenio Pérez" <eperezma@redhat.com>]

To split each SVQ in its own initialization routine let's us to restart
a VQ individually, and to keep future vhost_vdpa_restart_queue
symmetrical with vhost_vdpa_reset_queue.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 hw/virtio/vhost-vdpa.c | 67 ++++++++++++++++++++++++++----------------
 1 file changed, 41 insertions(+), 26 deletions(-)

diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index df2515a247..7248072989 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -1223,6 +1223,46 @@ static bool vhost_vdpa_svq_setup(struct vhost_dev *dev,
     return r == 0;
 }
 
+static bool vhost_vdpa_svq_start(struct vhost_dev *dev, unsigned i,
+                                 Error **errp)
+{
+    struct vhost_vdpa *v = dev->opaque;
+    VirtQueue *vq = virtio_get_queue(dev->vdev, dev->vq_index + i);
+    VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, i);
+    struct vhost_vring_addr addr = {
+        .index = dev->vq_index + i,
+    };
+    int r;
+    bool ok = vhost_vdpa_svq_setup(dev, svq, i, errp);
+    if (unlikely(!ok)) {
+        goto err;
+    }
+
+    vhost_svq_start(svq, dev->vdev, vq, v->iova_tree);
+    ok = vhost_vdpa_svq_map_rings(dev, svq, &addr, errp);
+    if (unlikely(!ok)) {
+        goto err_map;
+    }
+
+    /* Override vring GPA set by vhost subsystem */
+    r = vhost_vdpa_set_vring_dev_addr(dev, &addr);
+    if (unlikely(r != 0)) {
+        error_setg_errno(errp, -r, "Cannot set device address");
+        goto err_set_addr;
+    }
+
+    return true;
+
+err_set_addr:
+    vhost_vdpa_svq_unmap_rings(dev, g_ptr_array_index(v->shadow_vqs, i));
+
+err_map:
+    vhost_svq_stop(g_ptr_array_index(v->shadow_vqs, i));
+
+err:
+    return false;
+}
+
 static bool vhost_vdpa_svqs_start(struct vhost_dev *dev)
 {
     struct vhost_vdpa *v = dev->opaque;
@@ -1234,39 +1274,14 @@ static bool vhost_vdpa_svqs_start(struct vhost_dev *dev)
     }
 
     for (i = 0; i < v->shadow_vqs->len; ++i) {
-        VirtQueue *vq = virtio_get_queue(dev->vdev, dev->vq_index + i);
-        VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, i);
-        struct vhost_vring_addr addr = {
-            .index = dev->vq_index + i,
-        };
-        int r;
-        bool ok = vhost_vdpa_svq_setup(dev, svq, i, &err);
+        bool ok = vhost_vdpa_svq_start(dev, i, &err);
         if (unlikely(!ok)) {
             goto err;
         }
-
-        vhost_svq_start(svq, dev->vdev, vq, v->iova_tree);
-        ok = vhost_vdpa_svq_map_rings(dev, svq, &addr, &err);
-        if (unlikely(!ok)) {
-            goto err_map;
-        }
-
-        /* Override vring GPA set by vhost subsystem */
-        r = vhost_vdpa_set_vring_dev_addr(dev, &addr);
-        if (unlikely(r != 0)) {
-            error_setg_errno(&err, -r, "Cannot set device address");
-            goto err_set_addr;
-        }
     }
 
     return true;
 
-err_set_addr:
-    vhost_vdpa_svq_unmap_rings(dev, g_ptr_array_index(v->shadow_vqs, i));
-
-err_map:
-    vhost_svq_stop(g_ptr_array_index(v->shadow_vqs, i));
-
 err:
     error_reportf_err(err, "Cannot setup SVQ %u: ", i);
     for (unsigned j = 0; j < i; ++j) {
-- 
2.39.3