From: Xie Yongji <xieyongji@bytedance.com>
Date: Thu, 23 Mar 2023 05:30:40 +0000 (+0800)
Subject: vdpa: Add eventfd for the vdpa callback
X-Git-Tag: v6.6.17~4994^2~29
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=5e68470f4e80a4120e9ecec408f6ab4ad386bd4a;p=platform%2Fkernel%2Flinux-rpi.git

vdpa: Add eventfd for the vdpa callback

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

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Message-Id: <20230323053043.35-9-xieyongji@bytedance.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 7be9d9d..9cd878e 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.trigger = vq->call_ctx.ctx;
 		} else {
 			cb.callback = NULL;
 			cb.private = NULL;
+			cb.trigger = 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 f3826f4..2a095f3 100644
--- a/drivers/virtio/virtio_vdpa.c
+++ b/drivers/virtio/virtio_vdpa.c
@@ -196,6 +196,7 @@ 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.trigger = 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 2313db7..f2064fa 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -13,10 +13,16 @@
  * struct vdpa_calllback - vDPA callback definition.
  * @callback: interrupt callback function
  * @private: the data passed to the callback function
+ * @trigger: the eventfd for the callback (Optional).
+ *           When it is set, the vDPA driver must guarantee that
+ *           signaling it is functional equivalent to triggering
+ *           the callback. Then vDPA parent can signal it directly
+ *           instead of triggering the callback.
  */
 struct vdpa_callback {
 	irqreturn_t (*callback)(void *data);
 	void *private;
+	struct eventfd_ctx *trigger;
 };
 
 /**