On Tue, 14 Mar 2023 15:58:22 +0800, Jason Wang <jasowang@xxxxxxxxxx> wrote: > On Wed, Mar 8, 2023 at 2:44 PM Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> wrote: > > > > 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 b23d301effb5..216ac8654982 100644 > > --- a/drivers/virtio/virtio_ring.c > > +++ b/drivers/virtio/virtio_ring.c > > @@ -2190,6 +2190,10 @@ 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. > > Is it worth adding checks for those requirements? If we want to check, we need to check every SG, and I think the overhead is a bit big. If the driver is not implemented as these requirements, I think he will always encounter some abnormalities when testing. Thanks. > > Thanks > > > + * > > * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO). > > */ > > int virtqueue_add_sgs(struct virtqueue *_vq, > > @@ -2224,6 +2228,10 @@ 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, > > @@ -2246,6 +2254,10 @@ 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, > > @@ -2269,6 +2281,10 @@ 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
