[PATCH v3 08/11] vdpa: Add eventfd for the vdpa callback

[Xie Yongji]

Add eventfd for the vdpa callback so that user
can signal it directly instead of running the
callback. It will be used for vhost-vdpa case.

Signed-off-by: Xie Yongji <xieyongji@xxxxxxxxxxxxx>
---
 drivers/vhost/vdpa.c         | 2 ++
 drivers/virtio/virtio_vdpa.c | 1 +
 include/linux/vdpa.h         | 3 +++
 3 files changed, 6 insertions(+)

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index dc12dbd5b43b..ae89c0ccc2bb 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -599,9 +599,11 @@ static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
 		if (vq->call_ctx.ctx) {
 			cb.callback = vhost_vdpa_virtqueue_cb;
 			cb.private = vq;
+			cb.irq_ctx = vq->call_ctx.ctx;
 		} else {
 			cb.callback = NULL;
 			cb.private = NULL;
+			cb.irq_ctx = NULL;
 		}
 		ops->set_vq_cb(vdpa, idx, &cb);
 		vhost_vdpa_setup_vq_irq(v, idx);
diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
index 9eee8afabda8..a5cecafbc2d1 100644
--- a/drivers/virtio/virtio_vdpa.c
+++ b/drivers/virtio/virtio_vdpa.c
@@ -195,6 +195,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
 	/* Setup virtqueue callback */
 	cb.callback = callback ? virtio_vdpa_virtqueue_cb : NULL;
 	cb.private = info;
+	cb.irq_ctx = NULL;
 	ops->set_vq_cb(vdpa, index, &cb);
 	ops->set_vq_num(vdpa, index, virtqueue_get_vring_size(vq));
 
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 10bd22387276..94a7ec49583a 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -13,10 +13,13 @@
  * struct vdpa_calllback - vDPA callback definition.
  * @callback: interrupt callback function
  * @private: the data passed to the callback function
+ * @irq_ctx: the eventfd for the callback, user can signal
+ *           it directly instead of running the callback
  */
 struct vdpa_callback {
 	irqreturn_t (*callback)(void *data);
 	void *private;
+	struct eventfd_ctx *irq_ctx;
 };
 
 /**
-- 
2.20.1