[PATCH 2/3] hw/virtio: cleanup shared resources

[Albert Esteve <aesteve@redhat.com>]

Ensure that we cleanup all virtio shared
resources when the vhost devices is cleaned
up (after a hot unplug, or a crash).

To track all owned uuids of a device, add
a GSList to the vhost_dev struct. This way
we can avoid traversing the full table
for every cleanup, whether they actually
own any shared resource or not.

Signed-off-by: Albert Esteve <aesteve@redhat.com>
---
 hw/virtio/vhost-user.c    | 2 ++
 hw/virtio/vhost.c         | 4 ++++
 include/hw/virtio/vhost.h | 6 ++++++
 3 files changed, 12 insertions(+)

diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 5fdff0241f..04848d1fa0 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -1598,6 +1598,7 @@ vhost_user_backend_handle_shared_object_add(struct vhost_dev *dev,
     QemuUUID uuid;
 
     memcpy(uuid.data, object->uuid, sizeof(object->uuid));
+    dev->shared_uuids = g_slist_append(dev->shared_uuids, &uuid);
     return virtio_add_vhost_device(&uuid, dev);
 }
 
@@ -1623,6 +1624,7 @@ vhost_user_backend_handle_shared_object_remove(struct vhost_dev *dev,
     }
 
     memcpy(uuid.data, object->uuid, sizeof(object->uuid));
+    dev->shared_uuids = g_slist_remove_all(dev->shared_uuids, &uuid);
     return virtio_remove_resource(&uuid);
 }
 
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 9c9ae7109e..3aff94664b 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -16,6 +16,7 @@
 #include "qemu/osdep.h"
 #include "qapi/error.h"
 #include "hw/virtio/vhost.h"
+#include "hw/virtio/virtio-dmabuf.h"
 #include "qemu/atomic.h"
 #include "qemu/range.h"
 #include "qemu/error-report.h"
@@ -1599,6 +1600,9 @@ void vhost_dev_cleanup(struct vhost_dev *hdev)
     migrate_del_blocker(&hdev->migration_blocker);
     g_free(hdev->mem);
     g_free(hdev->mem_sections);
+    /* free virtio shared objects */
+    g_slist_foreach(hdev->shared_uuids, (GFunc)virtio_remove_resource, NULL);
+    g_slist_free_full(g_steal_pointer(&hdev->shared_uuids), g_free);
     if (hdev->vhost_ops) {
         hdev->vhost_ops->vhost_backend_cleanup(hdev);
     }
diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h
index 5e8183f64a..376bc8446d 100644
--- a/include/hw/virtio/vhost.h
+++ b/include/hw/virtio/vhost.h
@@ -118,6 +118,12 @@ struct vhost_dev {
      */
     uint64_t protocol_features;
 
+    /**
+     * @shared_uuids: contains the UUIDs of all the exported
+     * virtio objects owned by the vhost device.
+     */
+    GSList *shared_uuids;
+
     uint64_t max_queues;
     uint64_t backend_cap;
     /* @started: is the vhost device started? */
-- 
2.41.0