vhost: postpone rings addresses translation

This patch postpones rings addresses translations and checks, as
addresses sent by the master shuld not be interpreted as long as
ring is not started and enabled[0].

When protocol features aren't negotiated, the ring is started in
enabled state, so the addresses translations are postponed to
vhost_user_set_vring_kick().
Otherwise, it is postponed to when ring is enabled, in
vhost_user_set_vring_enable().

[0]: http://lists.nongnu.org/archive/html/qemu-devel/2017-05/msg04355.html

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Yuanhan Liu <yliu@fridaylinux.org>

diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index 2ea6c46..b873cce 100644 (file)
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -125,6 +125,7 @@ struct vhost_virtqueue {
 
        struct vring_used_elem  *shadow_used_ring;
        uint16_t                shadow_used_idx;
+       struct vhost_vring_addr ring_addrs;
 
        struct batch_copy_elem  *batch_copy_elems;
        uint16_t                batch_copy_nb_elems;

diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 34086a7..b2159e0 100644 (file)
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -356,6 +356,7 @@ static int
 vhost_user_set_vring_addr(struct virtio_net *dev, VhostUserMsg *msg)
 {
        struct vhost_virtqueue *vq;
+       struct vhost_vring_addr *addr = &msg->payload.addr;
 
        if (dev->mem == NULL)
                return -1;
@@ -363,35 +364,50 @@ vhost_user_set_vring_addr(struct virtio_net *dev, VhostUserMsg *msg)
        /* addr->index refers to the queue index. The txq 1, rxq is 0. */
        vq = dev->virtqueue[msg->payload.addr.index];
 
+       /*
+        * Rings addresses should not be interpreted as long as the ring is not
+        * started and enabled
+        */
+       memcpy(&vq->ring_addrs, addr, sizeof(*addr));
+
+       return 0;
+}
+
+static struct virtio_net *
+translate_ring_addresses(struct virtio_net *dev, int vq_index)
+{
+       struct vhost_virtqueue *vq = dev->virtqueue[vq_index];
+       struct vhost_vring_addr *addr = &vq->ring_addrs;
+
        /* The addresses are converted from QEMU virtual to Vhost virtual. */
        vq->desc = (struct vring_desc *)(uintptr_t)qva_to_vva(dev,
-                       msg->payload.addr.desc_user_addr);
+                       addr->desc_user_addr);
        if (vq->desc == 0) {
                RTE_LOG(ERR, VHOST_CONFIG,
                        "(%d) failed to find desc ring address.\n",
                        dev->vid);
-               return -1;
+               return NULL;
        }
 
-       dev = numa_realloc(dev, msg->payload.addr.index);
-       vq = dev->virtqueue[msg->payload.addr.index];
+       dev = numa_realloc(dev, vq_index);
+       vq = dev->virtqueue[vq_index];
 
        vq->avail = (struct vring_avail *)(uintptr_t)qva_to_vva(dev,
-                       msg->payload.addr.avail_user_addr);
+                       addr->avail_user_addr);
        if (vq->avail == 0) {
                RTE_LOG(ERR, VHOST_CONFIG,
                        "(%d) failed to find avail ring address.\n",
                        dev->vid);
-               return -1;
+               return NULL;
        }
 
        vq->used = (struct vring_used *)(uintptr_t)qva_to_vva(dev,
-                       msg->payload.addr.used_user_addr);
+                       addr->used_user_addr);
        if (vq->used == 0) {
                RTE_LOG(ERR, VHOST_CONFIG,
                        "(%d) failed to find used ring address.\n",
                        dev->vid);
-               return -1;
+               return NULL;
        }
 
        if (vq->last_used_idx != vq->used->idx) {
@@ -403,7 +419,7 @@ vhost_user_set_vring_addr(struct virtio_net *dev, VhostUserMsg *msg)
                vq->last_avail_idx = vq->used->idx;
        }
 
-       vq->log_guest_addr = msg->payload.addr.log_guest_addr;
+       vq->log_guest_addr = addr->log_guest_addr;
 
        LOG_DEBUG(VHOST_CONFIG, "(%d) mapped address desc: %p\n",
                        dev->vid, vq->desc);
@@ -414,7 +430,7 @@ vhost_user_set_vring_addr(struct virtio_net *dev, VhostUserMsg *msg)
        LOG_DEBUG(VHOST_CONFIG, "(%d) log_guest_addr: %" PRIx64 "\n",
                        dev->vid, vq->log_guest_addr);
 
-       return 0;
+       return dev;
 }
 
 /*
@@ -685,10 +701,11 @@ vhost_user_set_vring_call(struct virtio_net *dev, struct VhostUserMsg *pmsg)
 }
 
 static void
-vhost_user_set_vring_kick(struct virtio_net *dev, struct VhostUserMsg *pmsg)
+vhost_user_set_vring_kick(struct virtio_net **pdev, struct VhostUserMsg *pmsg)
 {
        struct vhost_vring_file file;
        struct vhost_virtqueue *vq;
+       struct virtio_net *dev = *pdev;
 
        file.index = pmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
        if (pmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)
@@ -698,6 +715,16 @@ vhost_user_set_vring_kick(struct virtio_net *dev, struct VhostUserMsg *pmsg)
        RTE_LOG(INFO, VHOST_CONFIG,
                "vring kick idx:%d file:%d\n", file.index, file.fd);
 
+       /*
+        * Interpret ring addresses only when ring is started and enabled.
+        * This is now if protocol features aren't supported.
+        */
+       if (!(dev->features & (1ULL << VHOST_USER_F_PROTOCOL_FEATURES))) {
+               *pdev = dev = translate_ring_addresses(dev, file.index);
+               if (!dev)
+                       return;
+       }
+
        vq = dev->virtqueue[file.index];
 
        /*
@@ -778,15 +805,29 @@ vhost_user_get_vring_base(struct virtio_net *dev,
  * enable the virtio queue pair.
  */
 static int
-vhost_user_set_vring_enable(struct virtio_net *dev,
+vhost_user_set_vring_enable(struct virtio_net **pdev,
                            VhostUserMsg *msg)
 {
+       struct virtio_net *dev = *pdev;
        int enable = (int)msg->payload.state.num;
 
        RTE_LOG(INFO, VHOST_CONFIG,
                "set queue enable: %d to qp idx: %d\n",
                enable, msg->payload.state.index);
 
+       /*
+        * Interpret ring addresses only when ring is started and enabled.
+        * This is now if protocol features are supported.
+        */
+       if (enable && (dev->features &
+                               (1ULL << VHOST_USER_F_PROTOCOL_FEATURES))) {
+               dev = translate_ring_addresses(dev, msg->payload.state.index);
+               if (!dev)
+                       return -1;
+
+               *pdev = dev;
+       }
+
        if (dev->notify_ops->vring_state_changed)
                dev->notify_ops->vring_state_changed(dev->vid,
                                msg->payload.state.index, enable);
@@ -1155,7 +1196,7 @@ vhost_user_msg_handler(int vid, int fd)
                break;
 
        case VHOST_USER_SET_VRING_KICK:
-               vhost_user_set_vring_kick(dev, &msg);
+               vhost_user_set_vring_kick(&dev, &msg);
                break;
        case VHOST_USER_SET_VRING_CALL:
                vhost_user_set_vring_call(dev, &msg);
@@ -1174,7 +1215,7 @@ vhost_user_msg_handler(int vid, int fd)
                break;
 
        case VHOST_USER_SET_VRING_ENABLE:
-               vhost_user_set_vring_enable(dev, &msg);
+               vhost_user_set_vring_enable(&dev, &msg);
                break;
        case VHOST_USER_SEND_RARP:
                vhost_user_send_rarp(dev, &msg);