@@ -2145,7 +2145,7 @@ static struct virtqueue *vring_create_virtqueue_packed(struct virtio_device *vde
vq->packed_ring = true;
vq->dma_dev = dma_dev;
vq->use_dma_api = vring_use_dma_api(vdev);
- vq->premapped = false;
+ vq->premapped = vq->use_dma_api && cfg_vq_get(cfg, premapped);
vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) &&
!cfg_vq_get(cfg, ctx);
@@ -2687,7 +2687,7 @@ static struct virtqueue *__vring_new_virtqueue(struct virtio_device *vdev,
#endif
vq->dma_dev = tp_cfg->dma_dev;
vq->use_dma_api = vring_use_dma_api(vdev);
- vq->premapped = false;
+ vq->premapped = vq->use_dma_api && cfg_vq_get(cfg, premapped);
vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) &&
!cfg_vq_get(cfg, ctx);
@@ -105,6 +105,7 @@ struct virtio_vq_config {
vq_callback_t **callbacks;
const char **names;
const bool *ctx;
+ const bool *premapped;
struct irq_affinity *desc;
};
If the premapped mode is enabled, the dma array(struct vring_desc_dma) of virtio core will not be allocated. That is judged when find_vqs() is called. To avoid allocating dma array in find_vqs() and releasing it immediately by virtqueue_set_dma_premapped(). This patch introduces a new parameter to find_vqs(). Then we can judge should we allocate the dma array(struct vring_desc_dma) or not inside find_vqs(). The driver must check the premapped mode of every vq after find_vqs(). Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> --- drivers/virtio/virtio_ring.c | 4 ++-- include/linux/virtio_config.h | 1 + 2 files changed, 3 insertions(+), 2 deletions(-)