diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 639c20b19e06..916479c9c72c 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -3106,4 +3106,73 @@ const struct vring *virtqueue_get_vring(const struct virtqueue *vq) } EXPORT_SYMBOL_GPL(virtqueue_get_vring); +/** + * virtqueue_dma_map_single_attrs - map DMA for _vq + * @_vq: the struct virtqueue we're talking about. + * @ptr: the pointer of the buffer to do dma + * @size: the size of the buffer to do dma + * @dir: DMA direction + * @attrs: DMA Attrs + * + * The caller calls this to do dma mapping in advance. The DMA address can be + * passed to this _vq when it is in pre-mapped mode. + * + * return DMA address. Caller should check that by virtqueue_dma_mapping_error(). + */ +dma_addr_t virtqueue_dma_map_single_attrs(struct virtqueue *_vq, void *ptr, + size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + if (!vq->use_dma_api) + return (dma_addr_t)virt_to_phys(ptr); + + return dma_map_single_attrs(vring_dma_dev(vq), ptr, size, dir, attrs); +} +EXPORT_SYMBOL_GPL(virtqueue_dma_map_single_attrs); + +/** + * virtqueue_dma_unmap_single_attrs - unmap DMA for _vq + * @_vq: the struct virtqueue we're talking about. + * @addr: the dma address to unmap + * @size: the size of the buffer + * @dir: DMA direction + * @attrs: DMA Attrs + * + * Unmap the address that is mapped by the virtqueue_dma_map_* APIs. + * + */ +void virtqueue_dma_unmap_single_attrs(struct virtqueue *_vq, dma_addr_t addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + if (!vq->use_dma_api) + return; + + dma_unmap_single_attrs(vring_dma_dev(vq), addr, size, dir, attrs); +} +EXPORT_SYMBOL_GPL(virtqueue_dma_unmap_single_attrs); + +/** + * virtqueue_dma_mapping_error - check dma address + * @_vq: the struct virtqueue we're talking about. + * @addr: DMA address + * + * Returns 0 means dma valid. Other means invalid dma address. + */ +int virtqueue_dma_mapping_error(struct virtqueue *_vq, dma_addr_t addr) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + if (!vq->use_dma_api) + return 0; + + return dma_mapping_error(vring_dma_dev(vq), addr); +} +EXPORT_SYMBOL_GPL(virtqueue_dma_mapping_error); + MODULE_LICENSE("GPL"); diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 49a640e0a6f4..79e3c74391e0 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -9,6 +9,7 @@ #include #include #include +#include /** * struct virtqueue - a queue to register buffers for sending or receiving. @@ -212,4 +213,11 @@ void unregister_virtio_driver(struct virtio_driver *drv); #define module_virtio_driver(__virtio_driver) \ module_driver(__virtio_driver, register_virtio_driver, \ unregister_virtio_driver) + +dma_addr_t virtqueue_dma_map_single_attrs(struct virtqueue *_vq, void *ptr, size_t size, + enum dma_data_direction dir, unsigned long attrs); +void virtqueue_dma_unmap_single_attrs(struct virtqueue *_vq, dma_addr_t addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs); +int virtqueue_dma_mapping_error(struct virtqueue *_vq, dma_addr_t addr); #endif /* _LINUX_VIRTIO_H */