Update the document of virtqueue_add_* series API, allowing the callers to use sg->dma_address to pass the dma address to Virtio Core. Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> --- drivers/virtio/virtio_ring.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index d5dffbe50070..0b198ec3ff92 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2202,6 +2202,10 @@ static inline int virtqueue_add(struct virtqueue *_vq, * Caller must ensure we don't call this with other virtqueue operations * at the same time (except where noted). * + * If the caller has done dma map then use sg->dma_address to pass dma address. + * If one sg->dma_address is used, then all sgs must use sg->dma_address; + * otherwise all sg->dma_address must be NULL. + * * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). */ int virtqueue_add_sgs(struct virtqueue *_vq, @@ -2236,6 +2240,10 @@ EXPORT_SYMBOL_GPL(virtqueue_add_sgs); * Caller must ensure we don't call this with other virtqueue operations * at the same time (except where noted). * + * If the caller has done dma map then use sg->dma_address to pass dma address. + * If one sg->dma_address is used, then all sgs must use sg->dma_address; + * otherwise all sg->dma_address must be NULL. + * * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). */ int virtqueue_add_outbuf(struct virtqueue *vq, @@ -2258,6 +2266,10 @@ EXPORT_SYMBOL_GPL(virtqueue_add_outbuf); * Caller must ensure we don't call this with other virtqueue operations * at the same time (except where noted). * + * If the caller has done dma map then use sg->dma_address to pass dma address. + * If one sg->dma_address is used, then all sgs must use sg->dma_address; + * otherwise all sg->dma_address must be NULL. + * * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). */ int virtqueue_add_inbuf(struct virtqueue *vq, @@ -2281,6 +2293,10 @@ EXPORT_SYMBOL_GPL(virtqueue_add_inbuf); * Caller must ensure we don't call this with other virtqueue operations * at the same time (except where noted). * + * If the caller has done dma map then use sg->dma_address to pass dma address. + * If one sg->dma_address is used, then all sgs must use sg->dma_address; + * otherwise all sg->dma_address must be NULL. + * * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). */ int virtqueue_add_inbuf_ctx(struct virtqueue *vq, -- 2.32.0.3.g01195cf9f _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization