[PATCH V3 2/3] vduse: suspend

[Steve Sistare]

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.sist...@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