[PATCHv2 08/14] virtio_ring: Add capacity check API
From: Michael S. Tsirkin <hidden>
Date: 2011-05-19 23:12:03
Also in:
kvm, lkml
Subsystem:
the rest, virtio core · Maintainers:
Linus Torvalds, "Michael S. Tsirkin", Jason Wang
From: Shirley Ma <mashirle-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Shirley Ma <xma-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org> Signed-off-by: Michael S. Tsirkin <redacted> --- drivers/virtio/virtio_ring.c | 8 ++++++++ include/linux/virtio.h | 5 +++++ 2 files changed, 13 insertions(+), 0 deletions(-)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 6578e1a..eed5f29 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c@@ -344,6 +344,14 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) } EXPORT_SYMBOL_GPL(virtqueue_get_buf); +int virtqueue_get_capacity(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + return vq->num_free; +} +EXPORT_SYMBOL_GPL(virtqueue_get_capacity); + void virtqueue_disable_cb(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq);
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index 7108857..58c0953 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h@@ -42,6 +42,9 @@ struct virtqueue { * vq: the struct virtqueue we're talking about. * len: the length written into the buffer * Returns NULL or the "data" token handed to add_buf. + * virtqueue_get_capacity: get the current capacity of the queue + * vq: the struct virtqueue we're talking about. + * Returns remaining capacity of the queue. * virtqueue_disable_cb: disable callbacks * vq: the struct virtqueue we're talking about. * Note that this is not necessarily synchronous, hence unreliable and only
@@ -89,6 +92,8 @@ void virtqueue_kick(struct virtqueue *vq); void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len); +int virtqueue_get_capacity(struct virtqueue *vq); + void virtqueue_disable_cb(struct virtqueue *vq); bool virtqueue_enable_cb(struct virtqueue *vq);
--
1.7.5.53.gc233e