[PATCH vhost v6 07/10] virtio: find_vqs: add new parameter premapped
From: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Date: 2024-03-27 11:14:40
Also in:
virtualization
Subsystem:
the rest, virtio core · Maintainers:
Linus Torvalds, "Michael S. Tsirkin", Jason Wang
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(-)
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; };
--
2.32.0.3.g01195cf9f