diff options
author | Xuan Zhuo <xuanzhuo@linux.alibaba.com> | 2023-08-10 20:30:56 +0800 |
---|---|---|
committer | Michael S. Tsirkin <mst@redhat.com> | 2023-09-03 18:10:23 -0400 |
commit | 8bd2f71054bd0bc997833e9825143672eb7e2801 (patch) | |
tree | d311672bfc9f0faad96a12cbf835a874dadefadd /drivers/virtio/virtio_ring.c | |
parent | b6253b4e21939f1bb54e8fdb84c23af9c3fb834a (diff) |
virtio_ring: introduce dma sync api for virtqueue
These API has been introduced:
* virtqueue_dma_need_sync
* virtqueue_dma_sync_single_range_for_cpu
* virtqueue_dma_sync_single_range_for_device
These APIs can be used together with the premapped mechanism to sync the
DMA address.
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Message-Id: <20230810123057.43407-12-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'drivers/virtio/virtio_ring.c')
-rw-r--r-- | drivers/virtio/virtio_ring.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 916479c9c72c..81ecb29c88f1 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -3175,4 +3175,80 @@ int virtqueue_dma_mapping_error(struct virtqueue *_vq, dma_addr_t addr) } EXPORT_SYMBOL_GPL(virtqueue_dma_mapping_error); +/** + * virtqueue_dma_need_sync - check a dma address needs sync + * @_vq: the struct virtqueue we're talking about. + * @addr: DMA address + * + * Check if the dma address mapped by the virtqueue_dma_map_* APIs needs to be + * synchronized + * + * return bool + */ +bool virtqueue_dma_need_sync(struct virtqueue *_vq, dma_addr_t addr) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + if (!vq->use_dma_api) + return false; + + return dma_need_sync(vring_dma_dev(vq), addr); +} +EXPORT_SYMBOL_GPL(virtqueue_dma_need_sync); + +/** + * virtqueue_dma_sync_single_range_for_cpu - dma sync for cpu + * @_vq: the struct virtqueue we're talking about. + * @addr: DMA address + * @offset: DMA address offset + * @size: buf size for sync + * @dir: DMA direction + * + * Before calling this function, use virtqueue_dma_need_sync() to confirm that + * the DMA address really needs to be synchronized + * + */ +void virtqueue_dma_sync_single_range_for_cpu(struct virtqueue *_vq, + dma_addr_t addr, + unsigned long offset, size_t size, + enum dma_data_direction dir) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + struct device *dev = vring_dma_dev(vq); + + if (!vq->use_dma_api) + return; + + dma_sync_single_range_for_cpu(dev, addr, offset, size, + DMA_BIDIRECTIONAL); +} +EXPORT_SYMBOL_GPL(virtqueue_dma_sync_single_range_for_cpu); + +/** + * virtqueue_dma_sync_single_range_for_device - dma sync for device + * @_vq: the struct virtqueue we're talking about. + * @addr: DMA address + * @offset: DMA address offset + * @size: buf size for sync + * @dir: DMA direction + * + * Before calling this function, use virtqueue_dma_need_sync() to confirm that + * the DMA address really needs to be synchronized + */ +void virtqueue_dma_sync_single_range_for_device(struct virtqueue *_vq, + dma_addr_t addr, + unsigned long offset, size_t size, + enum dma_data_direction dir) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + struct device *dev = vring_dma_dev(vq); + + if (!vq->use_dma_api) + return; + + dma_sync_single_range_for_device(dev, addr, offset, size, + DMA_BIDIRECTIONAL); +} +EXPORT_SYMBOL_GPL(virtqueue_dma_sync_single_range_for_device); + MODULE_LICENSE("GPL"); |