vhost-user: handle message to enable vring

This message is used to enable/disable a specific vring queue pair.
The first queue pair is enabled by default.

Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Acked-by: Flavio Leitner <fbl@sysclose.org>
Acked-by: Huawei Xie <huawei.xie@intel.com>

diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index 9a32a95..426a70d 100644 (file)
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -89,6 +89,7 @@ struct vhost_virtqueue {
        volatile uint16_t       last_used_idx_res;      /**< Used for multiple devices reserving buffers. */
        int                     callfd;                 /**< Used to notify the guest (trigger interrupt). */
        int                     kickfd;                 /**< Currently unused as polling mode is enabled. */
+       int                     enabled;
        struct buf_vector       buf_vec[BUF_VECTOR_MAX];        /**< for scatter RX. */
 } __rte_cache_aligned;
 
@@ -132,7 +133,7 @@ struct virtio_memory {
 };
 
 /**
- * Device operations to add/remove device.
+ * Device and vring operations.
  *
  * Make sure to set VIRTIO_DEV_RUNNING to the device flags in new_device and
  * remove it in destroy_device.
@@ -141,12 +142,18 @@ struct virtio_memory {
 struct virtio_net_device_ops {
        int (*new_device)(struct virtio_net *); /**< Add device. */
        void (*destroy_device)(volatile struct virtio_net *);   /**< Remove device. */
+
+       int (*vring_state_changed)(struct virtio_net *dev, uint16_t queue_id, int enable);      /**< triggered when a vring is enabled or disabled */
 };
 
 static inline uint16_t __attribute__((always_inline))
 rte_vring_available_entries(struct virtio_net *dev, uint16_t queue_id)
 {
        struct vhost_virtqueue *vq = dev->virtqueue[queue_id];
+
+       if (!vq->enabled)
+               return 0;
+
        return *(volatile uint16_t *)&vq->avail->idx - vq->last_used_idx_res;
 }
 

diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c
index 1ec8850..9322ce6 100644 (file)
--- a/lib/librte_vhost/vhost_rxtx.c
+++ b/lib/librte_vhost/vhost_rxtx.c
@@ -83,6 +83,9 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
        }
 
        vq = dev->virtqueue[queue_id];
+       if (unlikely(vq->enabled == 0))
+               return 0;
+
        count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
 
        /*
@@ -275,6 +278,7 @@ copy_from_mbuf_to_vring(struct virtio_net *dev, uint32_t queue_id,
         * (guest physical addr -> vhost virtual addr)
         */
        vq = dev->virtqueue[queue_id];
+
        vb_addr = gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
        vb_hdr_addr = vb_addr;
 
@@ -482,6 +486,9 @@ virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id,
        }
 
        vq = dev->virtqueue[queue_id];
+       if (unlikely(vq->enabled == 0))
+               return 0;
+
        count = RTE_MIN((uint32_t)MAX_PKT_BURST, count);
 
        if (count == 0)
@@ -583,6 +590,9 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id,
        }
 
        vq = dev->virtqueue[queue_id];
+       if (unlikely(vq->enabled == 0))
+               return 0;
+
        avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
 
        /* If there are no available buffers then return. */

diff --git a/lib/librte_vhost/vhost_user/vhost-net-user.c b/lib/librte_vhost/vhost_user/vhost-net-user.c
index 8675cd4..f681676 100644 (file)
--- a/lib/librte_vhost/vhost_user/vhost-net-user.c
+++ b/lib/librte_vhost/vhost_user/vhost-net-user.c
@@ -99,6 +99,7 @@ static const char *vhost_message_str[VHOST_USER_MAX] = {
        [VHOST_USER_GET_PROTOCOL_FEATURES]  = "VHOST_USER_GET_PROTOCOL_FEATURES",
        [VHOST_USER_SET_PROTOCOL_FEATURES]  = "VHOST_USER_SET_PROTOCOL_FEATURES",
        [VHOST_USER_GET_QUEUE_NUM]  = "VHOST_USER_GET_QUEUE_NUM",
+       [VHOST_USER_SET_VRING_ENABLE]  = "VHOST_USER_SET_VRING_ENABLE",
 };
 
 /**
@@ -428,6 +429,10 @@ vserver_message_handler(int connfd, void *dat, int *remove)
                send_vhost_message(connfd, &msg);
                break;
 
+       case VHOST_USER_SET_VRING_ENABLE:
+               user_set_vring_enable(ctx, &msg.payload.state);
+               break;
+
        default:
                break;
 

diff --git a/lib/librte_vhost/vhost_user/vhost-net-user.h b/lib/librte_vhost/vhost_user/vhost-net-user.h
index 389d21d..38637cc 100644 (file)
--- a/lib/librte_vhost/vhost_user/vhost-net-user.h
+++ b/lib/librte_vhost/vhost_user/vhost-net-user.h
@@ -66,6 +66,7 @@ typedef enum VhostUserRequest {
        VHOST_USER_GET_PROTOCOL_FEATURES = 15,
        VHOST_USER_SET_PROTOCOL_FEATURES = 16,
        VHOST_USER_GET_QUEUE_NUM = 17,
+       VHOST_USER_SET_VRING_ENABLE = 18,
        VHOST_USER_MAX
 } VhostUserRequest;
 

diff --git a/lib/librte_vhost/vhost_user/virtio-net-user.c b/lib/librte_vhost/vhost_user/virtio-net-user.c
index 7fc3805..a998ad8 100644 (file)
--- a/lib/librte_vhost/vhost_user/virtio-net-user.c
+++ b/lib/librte_vhost/vhost_user/virtio-net-user.c
@@ -312,6 +312,33 @@ user_get_vring_base(struct vhost_device_ctx ctx,
        return 0;
 }
 
+/*
+ * when virtio queues are ready to work, qemu will send us to
+ * enable the virtio queue pair.
+ */
+int
+user_set_vring_enable(struct vhost_device_ctx ctx,
+                     struct vhost_vring_state *state)
+{
+       struct virtio_net *dev = get_device(ctx);
+       uint16_t base_idx = state->index;
+       int enable = (int)state->num;
+
+       RTE_LOG(INFO, VHOST_CONFIG,
+               "set queue enable: %d to qp idx: %d\n",
+               enable, state->index);
+
+       if (notify_ops->vring_state_changed) {
+               notify_ops->vring_state_changed(dev, base_idx / VIRTIO_QNUM,
+                                               enable);
+       }
+
+       dev->virtqueue[base_idx + VIRTIO_RXQ]->enabled = enable;
+       dev->virtqueue[base_idx + VIRTIO_TXQ]->enabled = enable;
+
+       return 0;
+}
+
 void
 user_destroy_device(struct vhost_device_ctx ctx)
 {

diff --git a/lib/librte_vhost/vhost_user/virtio-net-user.h b/lib/librte_vhost/vhost_user/virtio-net-user.h
index e7a6ff4..d46057e 100644 (file)
--- a/lib/librte_vhost/vhost_user/virtio-net-user.h
+++ b/lib/librte_vhost/vhost_user/virtio-net-user.h
@@ -50,5 +50,8 @@ void user_set_protocol_features(struct vhost_device_ctx ctx,
 
 int user_get_vring_base(struct vhost_device_ctx, struct vhost_vring_state *);
 
+int user_set_vring_enable(struct vhost_device_ctx ctx,
+                         struct vhost_vring_state *state);
+
 void user_destroy_device(struct vhost_device_ctx);
 #endif

diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
index 772f835..48629d0 100644 (file)
--- a/lib/librte_vhost/virtio-net.c
+++ b/lib/librte_vhost/virtio-net.c
@@ -254,7 +254,7 @@ rm_config_ll_entry(struct virtio_net_config_ll *ll_dev,
 }
 
 static void
-init_vring_queue(struct vhost_virtqueue *vq)
+init_vring_queue(struct vhost_virtqueue *vq, int qp_idx)
 {
        memset(vq, 0, sizeof(struct vhost_virtqueue));
 
@@ -263,13 +263,19 @@ init_vring_queue(struct vhost_virtqueue *vq)
 
        /* Backends are set to -1 indicating an inactive device. */
        vq->backend = -1;
+
+       /* always set the default vq pair to enabled */
+       if (qp_idx == 0)
+               vq->enabled = 1;
 }
 
 static void
 init_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx)
 {
-       init_vring_queue(dev->virtqueue[qp_idx * VIRTIO_QNUM + VIRTIO_RXQ]);
-       init_vring_queue(dev->virtqueue[qp_idx * VIRTIO_QNUM + VIRTIO_TXQ]);
+       uint32_t base_idx = qp_idx * VIRTIO_QNUM;
+
+       init_vring_queue(dev->virtqueue[base_idx + VIRTIO_RXQ], qp_idx);
+       init_vring_queue(dev->virtqueue[base_idx + VIRTIO_TXQ], qp_idx);
 }
 
 static int