diff options
| author | Xuan Zhuo <xuanzhuo@linux.alibaba.com> | 2023-08-10 20:30:50 +0800 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2023-09-03 18:10:23 -0400 |
| commit | 2df64759071bdca2a12edb9af4f071e4419ad745 (patch) | |
| tree | 93b5c07e34c34572f96514dd1366394cc0f27911 | |
| parent | d7344a2f71e38eb04fc16e3fef4f0580f42cbbd5 (diff) | |
| download | linux-2df64759071bdca2a12edb9af4f071e4419ad745.tar.gz | |
virtio_ring: introduce virtqueue_dma_dev()
Added virtqueue_dma_dev() to get DMA device for virtio. Then the
caller can do dma operation in advance. The purpose is to keep memory
mapped across multiple add/get buf operations.
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230810123057.43407-6-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
| -rw-r--r-- | drivers/virtio/virtio_ring.c | 17 | ||||
| -rw-r--r-- | include/linux/virtio.h | 2 |
2 files changed, 19 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index f9f772e85a38b9..bb3d73d221cd5b 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2266,6 +2266,23 @@ int virtqueue_add_inbuf_ctx(struct virtqueue *vq, EXPORT_SYMBOL_GPL(virtqueue_add_inbuf_ctx); /** + * virtqueue_dma_dev - get the dma dev + * @_vq: the struct virtqueue we're talking about. + * + * Returns the dma dev. That can been used for dma api. + */ +struct device *virtqueue_dma_dev(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + if (vq->use_dma_api) + return vring_dma_dev(vq); + else + return NULL; +} +EXPORT_SYMBOL_GPL(virtqueue_dma_dev); + +/** * virtqueue_kick_prepare - first half of split virtqueue_kick call. * @_vq: the struct virtqueue * diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 8add380388772c..bd55a05eec04f7 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -61,6 +61,8 @@ int virtqueue_add_sgs(struct virtqueue *vq, void *data, gfp_t gfp); +struct device *virtqueue_dma_dev(struct virtqueue *vq); + bool virtqueue_kick(struct virtqueue *vq); bool virtqueue_kick_prepare(struct virtqueue *vq); |