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From:   =?UTF-8?q?Eugenio=20P=C3=A9rez?= <eperezma@redhat.com>
To:     mst@redhat.com, Jason Wang <jasowang@redhat.com>
Cc:     Zhu Lingshan <lingshan.zhu@intel.com>,
        virtualization@lists.linux-foundation.org,
        "Gonglei (Arei)" <arei.gonglei@huawei.com>, longpeng2@huawei.com,
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        Parav Pandit <parav@mellanox.com>,
        Gautam Dawar <gdawar@xilinx.com>,
        Dragos Tatulea <dtatulea@nvidia.com>,
        Laurent Vivier <lvivier@redhat.com>, linux-api@vger.kernel.org,
        Liuxiangdong <liuxiangdong5@huawei.com>,
        linux-kernel@vger.kernel.org, alvaro.karsz@solid-run.com,
        Shannon Nelson <snelson@pensando.io>,
        Stefano Garzarella <sgarzare@redhat.com>,
        Cindy Lu <lulu@redhat.com>, si-wei.liu@oracle.com,
        Harpreet Singh Anand <hanand@xilinx.com>
Subject: [PATCH v2 1/4] vdpa: add VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK flag
Date:   Fri,  9 Jun 2023 11:21:24 +0200
Message-Id: <20230609092127.170673-2-eperezma@redhat.com>
In-Reply-To: <20230609092127.170673-1-eperezma@redhat.com>
References: <20230609092127.170673-1-eperezma@redhat.com>
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This feature flag allows the driver enabling virtqueues both before and
after DRIVER_OK.

This is needed for software assisted live migration, so userland can
restore the device status in devices with control virtqueue before the
dataplane is enabled.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Shannon Nelson <shannon.nelson@amd.com>
---
 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 c5690a8992d8..4889e6d70b15 100644
--- a/include/uapi/linux/vhost_types.h
+++ b/include/uapi/linux/vhost_types.h
@@ -165,5 +165,9 @@ struct vhost_vdpa_iova_range {
 #define VHOST_BACKEND_F_SUSPEND  0x4
 /* Device can be resumed */
 #define VHOST_BACKEND_F_RESUME  0x5
+/* Device supports the driver enabling virtqueues both before and after
+ * DRIVER_OK
+ */
+#define VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK  0x6
 
 #endif
-- 
2.31.1