[PATCH vhost v4 02/15] vdpa: Add VHOST_BACKEND_F_CHANGEABLE_VQ_ADDR_IN_SUSPEND flag

[Dragos Tatulea]

The virtio spec doesn't allow changing virtqueue addresses after
DRIVER_OK. Some devices do support this operation when the device is
suspended. The VHOST_BACKEND_F_CHANGEABLE_VQ_ADDR_IN_SUSPEND flag
advertises this support as a backend features.

Signed-off-by: Dragos Tatulea <dtatulea@xxxxxxxxxx>
Suggested-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
---
 include/uapi/linux/vhost_types.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/uapi/linux/vhost_types.h b/include/uapi/linux/vhost_types.h
index d7656908f730..aacd067afc89 100644
--- a/include/uapi/linux/vhost_types.h
+++ b/include/uapi/linux/vhost_types.h
@@ -192,5 +192,9 @@ struct vhost_vdpa_iova_range {
 #define VHOST_BACKEND_F_DESC_ASID    0x7
 /* IOTLB don't flush memory mapping across device reset */
 #define VHOST_BACKEND_F_IOTLB_PERSIST  0x8
+/* Device supports changing virtqueue addresses when device is suspended
+ * and is in state DRIVER_OK.
+ */
+#define VHOST_BACKEND_F_CHANGEABLE_VQ_ADDR_IN_SUSPEND  0x9
 
 #endif
-- 
2.43.0