[dpdk-dev] [PATCH v2 18/19] vhost: iommu: Invalidate vring in case of matching IOTLB invalidate

[Maxime Coquelin]

As soon as a page used by a ring is invalidated, the access_ok flag
is cleared, so that processing threads try to map them again.

Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
---
 lib/librte_vhost/vhost.c      | 14 ++++++++++++++
 lib/librte_vhost/vhost.h      |  1 +
 lib/librte_vhost/vhost_user.c | 38 +++++++++++++++++++++++++++++++++-----
 3 files changed, 48 insertions(+), 5 deletions(-)

diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
index ef54835a6..061f08a69 100644
--- a/lib/librte_vhost/vhost.c
+++ b/lib/librte_vhost/vhost.c
@@ -172,6 +172,20 @@ vring_translate(struct virtio_net *dev, struct 
vhost_virtqueue *vq)
        return 0;
 }
 
+void vring_invalidate(struct virtio_net *dev, struct vhost_virtqueue *vq)
+{
+       if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))
+               vhost_user_iotlb_wr_lock(vq);
+
+       vq->access_ok = 0;
+       vq->desc = NULL;
+       vq->avail = NULL;
+       vq->used = NULL;
+
+       if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))
+               vhost_user_iotlb_wr_unlock(vq);
+}
+
 static void
 init_vring_queue(struct virtio_net *dev, uint32_t vring_idx)
 {
diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index b3fe6bb8e..fb48f3012 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -380,6 +380,7 @@ void vhost_backend_cleanup(struct virtio_net *dev);
 uint64_t __vhost_iova_to_vva(struct virtio_net *dev, struct vhost_virtqueue 
*vq,
                        uint64_t iova, uint64_t size, uint8_t perm);
 int vring_translate(struct virtio_net *dev, struct vhost_virtqueue *vq);
+void vring_invalidate(struct virtio_net *dev, struct vhost_virtqueue *vq);
 
 static __rte_always_inline uint64_t
 vhost_iova_to_vva(struct virtio_net *dev, struct vhost_virtqueue *vq,
diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 6d2c4d191..cef044307 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -391,11 +391,7 @@ vhost_user_set_vring_addr(struct virtio_net *dev, 
VhostUserMsg *msg)
         */
        memcpy(&vq->ring_addrs, addr, sizeof(*addr));
 
-       vq->desc = NULL;
-       vq->avail = NULL;
-       vq->used = NULL;
-
-       vq->access_ok = 0;
+       vring_invalidate(dev, vq);
 
        return 0;
 }
@@ -1012,6 +1008,35 @@ is_vring_iotlb_update(struct vhost_virtqueue *vq, struct 
vhost_iotlb_msg *imsg)
 }
 
 static int
+is_vring_iotlb_invalidate(struct vhost_virtqueue *vq,
+                               struct vhost_iotlb_msg *imsg)
+{
+       uint64_t istart, iend, vstart, vend;
+
+       istart = imsg->iova;
+       iend = istart + imsg->size - 1;
+
+       vstart = (uint64_t)vq->desc;
+       vend = vstart + sizeof(struct vring_desc) * vq->size - 1;
+       if (vstart <= iend && istart <= vend)
+               return 1;
+
+       vstart = (uint64_t)vq->avail;
+       vend = vstart + sizeof(struct vring_avail);
+       vend += sizeof(uint16_t) * vq->size - 1;
+       if (vstart <= iend && istart <= vend)
+               return 1;
+
+       vstart = (uint64_t)vq->used;
+       vend = vstart + sizeof(struct vring_used);
+       vend += sizeof(struct vring_used_elem) * vq->size - 1;
+       if (vstart <= iend && istart <= vend)
+               return 1;
+
+       return 0;
+}
+
+static int
 vhost_user_iotlb_msg(struct virtio_net **pdev, struct VhostUserMsg *msg)
 {
        struct virtio_net *dev = *pdev;
@@ -1041,6 +1066,9 @@ vhost_user_iotlb_msg(struct virtio_net **pdev, struct 
VhostUserMsg *msg)
 
                        vhost_user_iotlb_cache_remove(vq, imsg->iova,
                                        imsg->size);
+
+                       if (is_vring_iotlb_invalidate(vq, imsg))
+                               vring_invalidate(dev, vq);
                }
                break;
        default:
-- 
2.13.5