Re: [PATCH v2 18/19] vdpa: Add device migration blocker

[Jason Wang]

On Fri, Jul 15, 2022 at 12:32 AM Eugenio Pérez <eperezma@redhat.com> wrote:
>
> Since the vhost-vdpa device is exposing _F_LOG,

I may miss something but I think it doesn't?

Note that the features were fetched from the vDPA parent.

Thanks

> adding a migration blocker if
> it uses CVQ.
>
> Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
> ---
>  include/hw/virtio/vhost-vdpa.h |  1 +
>  hw/virtio/vhost-vdpa.c         | 14 ++++++++++++++
>  2 files changed, 15 insertions(+)
>
> diff --git a/include/hw/virtio/vhost-vdpa.h b/include/hw/virtio/vhost-vdpa.h
> index 1111d85643..d10a89303e 100644
> --- a/include/hw/virtio/vhost-vdpa.h
> +++ b/include/hw/virtio/vhost-vdpa.h
> @@ -35,6 +35,7 @@ typedef struct vhost_vdpa {
>      bool shadow_vqs_enabled;
>      /* IOVA mapping used by the Shadow Virtqueue */
>      VhostIOVATree *iova_tree;
> +    Error *migration_blocker;
>      GPtrArray *shadow_vqs;
>      const VhostShadowVirtqueueOps *shadow_vq_ops;
>      void *shadow_vq_ops_opaque;
> diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
> index beaaa7049a..795ed5a049 100644
> --- a/hw/virtio/vhost-vdpa.c
> +++ b/hw/virtio/vhost-vdpa.c
> @@ -20,6 +20,7 @@
>  #include "hw/virtio/vhost-shadow-virtqueue.h"
>  #include "hw/virtio/vhost-vdpa.h"
>  #include "exec/address-spaces.h"
> +#include "migration/blocker.h"
>  #include "qemu/cutils.h"
>  #include "qemu/main-loop.h"
>  #include "cpu.h"
> @@ -1022,6 +1023,13 @@ static bool vhost_vdpa_svqs_start(struct vhost_dev 
> *dev)
>          return true;
>      }
>
> +    if (v->migration_blocker) {
> +        int r = migrate_add_blocker(v->migration_blocker, &err);
> +        if (unlikely(r < 0)) {
> +            goto err_migration_blocker;
> +        }
> +    }
> +
>      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);
> @@ -1064,6 +1072,9 @@ err:
>          vhost_svq_stop(svq);
>      }
>
> +err_migration_blocker:
> +    error_reportf_err(err, "Cannot setup SVQ %u: ", i);
> +
>      return false;
>  }
>
> @@ -1083,6 +1094,9 @@ static bool vhost_vdpa_svqs_stop(struct vhost_dev *dev)
>          }
>      }
>
> +    if (v->migration_blocker) {
> +        migrate_del_blocker(v->migration_blocker);
> +    }
>      return true;
>  }
>
> --
> 2.31.1
>