On Wed, Jul 12, 2017 at 08:40:18PM +0800, Wei Wang wrote: > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > index 28b0e96..9f27101 100644 > --- a/include/linux/virtio.h > +++ b/include/linux/virtio.h > @@ -57,8 +57,28 @@ int virtqueue_add_sgs(struct virtqueue *vq, > void *data, > gfp_t gfp); > > +/* A desc with this init id is treated as an invalid desc */ > +#define VIRTQUEUE_DESC_ID_INIT UINT_MAX > +int virtqueue_add_chain_desc(struct virtqueue *_vq, > + uint64_t addr, > + uint32_t len, > + unsigned int *head_id, > + unsigned int *prev_id, > + bool in); > + > +int virtqueue_add_chain(struct virtqueue *_vq, > + unsigned int head, > + bool indirect, > + struct vring_desc *indirect_desc, > + void *data, > + void *ctx); > + > bool virtqueue_kick(struct virtqueue *vq); > > +bool virtqueue_kick_sync(struct virtqueue *vq); > + > +bool virtqueue_kick_async(struct virtqueue *vq, wait_queue_head_t wq); > + > bool virtqueue_kick_prepare(struct virtqueue *vq); > > bool virtqueue_notify(struct virtqueue *vq);
I don't much care for this API. It does exactly what balloon needs, but at cost of e.g. transparently busy-waiting. Unlikely to be a good fit for anything else. If you don't like my original _first/_next/_last, you will need to come up with something else. -- MST
