diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 3f78a3a1eb75..4c85349024c1 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -553,11 +553,15 @@ static int init_vqs(struct virtio_balloon *vb) virtqueue_kick(vb->stats_vq); } - if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { vb->free_page_vq = vqs[VIRTIO_BALLOON_VQ_FREE_PAGE]; + virtqueue_disable_dma_api_for_buffers(vb->free_page_vq); + } - if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_REPORTING)) + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_REPORTING)) { vb->reporting_vq = vqs[VIRTIO_BALLOON_VQ_REPORTING]; + virtqueue_disable_dma_api_for_buffers(vb->reporting_vq); + } return 0; } diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 2e7689bb933b..3eca7140bd80 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2863,4 +2863,14 @@ const struct vring *virtqueue_get_vring(struct virtqueue *vq) } EXPORT_SYMBOL_GPL(virtqueue_get_vring); +/* + * Prevents use of DMA API for buffers passed via the specified virtqueue. + * DMA API may still be used for the vrings themselves. + */ +void virtqueue_disable_dma_api_for_buffers(struct virtqueue *vq) +{ + to_vvq(vq)->use_dma_api = false; +} +EXPORT_SYMBOL_GPL(virtqueue_disable_dma_api_for_buffers); + MODULE_LICENSE("GPL"); diff --git a/include/linux/virtio.h b/include/linux/virtio.h index dcab9c7e8784..34e936343ae4 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -96,6 +96,8 @@ dma_addr_t virtqueue_get_used_addr(struct virtqueue *vq); int virtqueue_resize(struct virtqueue *vq, u32 num, void (*recycle)(struct virtqueue *vq, void *buf)); +void virtqueue_disable_dma_api_for_buffers(struct virtqueue *vq); + /** * struct virtio_device - representation of a device using virtio * @index: unique position on the virtio bus