| Message ID | 20240327111430.108787-8-xuanzhuo@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | virtio: drivers maintain dma info for premapped vq | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Guessing tree name failed - patch did not apply |
On Wed, Mar 27, 2024 at 7:14 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: > > 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> Acked-by: Jason Wang <jasowang@redhat.com> Thanks
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 08e4f6e1d722..bbdeab3a9648 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2148,7 +2148,7 @@ 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, vq, premapped); vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) && !cfg_vq_get(cfg, vq, ctx); @@ -2696,7 +2696,7 @@ 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, vq, premapped); vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) && !cfg_vq_get(cfg, vq, ctx); diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 370e79df50c4..80b7974ca9ff 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -29,6 +29,8 @@ typedef void vq_callback_t(struct virtqueue *); * @ctx: (optional) array of context. If the value of the vq in the array * is true, the driver can pass ctx to virtio core when adding bufs to * virtqueue. + * @premapped: (optional) array of premapped. If the value of the vq in the + * array is true, the vq will try to enable premapped mode. * @desc: desc for interrupts */ struct virtio_vq_config { @@ -38,6 +40,7 @@ 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 | 3 +++ 2 files changed, 5 insertions(+), 2 deletions(-)