[PATCH V3 2/3] vduse: suspend

[Steve Sistare <steven.sistare@oracle.com>]

Support the suspend operation.  There is little to do, except flush to
guarantee no workers are running when suspend returns.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
---
 drivers/vdpa/vdpa_user/vduse_dev.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
index 73c89701fc9d..7dc46f771f12 100644
--- a/drivers/vdpa/vdpa_user/vduse_dev.c
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c
@@ -472,6 +472,18 @@ static void vduse_dev_reset(struct vduse_dev *dev)
 	up_write(&dev->rwsem);
 }
 
+static void vduse_flush_work(struct vduse_dev *dev)
+{
+	flush_work(&dev->inject);
+
+	for (int i = 0; i < dev->vq_num; i++) {
+		struct vduse_virtqueue *vq = dev->vqs[i];
+
+		flush_work(&vq->inject);
+		flush_work(&vq->kick);
+	}
+}
+
 static int vduse_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 idx,
 				u64 desc_area, u64 driver_area,
 				u64 device_area)
@@ -724,6 +736,17 @@ static int vduse_vdpa_reset(struct vdpa_device *vdpa)
 	return ret;
 }
 
+static int vduse_vdpa_suspend(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	down_write(&dev->rwsem);
+	vduse_flush_work(dev);
+	up_write(&dev->rwsem);
+
+	return 0;
+}
+
 static u32 vduse_vdpa_get_generation(struct vdpa_device *vdpa)
 {
 	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
@@ -806,6 +829,7 @@ static const struct vdpa_config_ops vduse_vdpa_config_ops = {
 	.set_vq_affinity	= vduse_vdpa_set_vq_affinity,
 	.get_vq_affinity	= vduse_vdpa_get_vq_affinity,
 	.reset			= vduse_vdpa_reset,
+	.suspend		= vduse_vdpa_suspend,
 	.set_map		= vduse_vdpa_set_map,
 	.free			= vduse_vdpa_free,
 };
-- 
2.39.3