vdpa: move iova tree to the shared struct

Next patches will register the vhost_vdpa memory listener while the VM
is migrating at the destination, so we can map the memory to the device
before stopping the VM at the source.  The main goal is to reduce the
downtime.

However, the destination QEMU is unaware of which vhost_vdpa device will
register its memory_listener.  If the source guest has CVQ enabled, it
will be the CVQ device.  Otherwise, it  will be the first one.

Move the iova tree to VhostVDPAShared so all vhost_vdpa can use it,
rather than always in the first or last vhost_vdpa.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-3-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/include/hw/virtio/vhost-vdpa.h b/include/hw/virtio/vhost-vdpa.h
index eb1a56d..ac03605 100644
--- a/include/hw/virtio/vhost-vdpa.h
+++ b/include/hw/virtio/vhost-vdpa.h
@@ -32,6 +32,8 @@ typedef struct VhostVDPAHostNotifier {
 
 /* Info shared by all vhost_vdpa device models */
 typedef struct vhost_vdpa_shared {
+    /* IOVA mapping used by the Shadow Virtqueue */
+    VhostIOVATree *iova_tree;
 } VhostVDPAShared;
 
 typedef struct vhost_vdpa {
@@ -48,8 +50,6 @@ typedef struct vhost_vdpa {
     bool shadow_data;
     /* Device suspended successfully */
     bool suspended;
-    /* IOVA mapping used by the Shadow Virtqueue */
-    VhostIOVATree *iova_tree;
     VhostVDPAShared *shared;
     GPtrArray *shadow_vqs;
     const VhostShadowVirtqueueOps *shadow_vq_ops;