vhost: fix build with kernel < 3.8

Fix build error:
  virtio-net.c:80:89: error: ‘VIRTIO_NET_F_MQ’ undeclared here
  rte_virtio_net.h:109: error: ‘VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX’ undeclared here

Above two virtio-net MQ macros are introduced since kernel v3.8.
For older kernel, we should not reference them directly, hence,
this patch introduced two wrapper macros, with proper values
being set depending on we support MQ or not.

Fixes: b09b198bfb5c ("vhost-user: announce queue number in message")
Reported-by: Yongjie Gu <yongjiex.gu@intel.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Tested-by: David Marchand <david.marchand@6wind.com>

diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index 426a70dacaad45454218f6fd3955c732fdb8b0c7..b6386f91c3d8c574a15260448426071ed9d5f5ff 100644 (file)
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -93,6 +93,21 @@ struct vhost_virtqueue {
        struct buf_vector       buf_vec[BUF_VECTOR_MAX];        /**< for scatter RX. */
 } __rte_cache_aligned;
 
+
+/*
+ * Make an extra wrapper for VIRTIO_NET_F_MQ and
+ * VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX as they are
+ * introduced since kernel v3.8. This makes our
+ * code buildable for older kernel.
+ */
+#ifdef VIRTIO_NET_F_MQ
+ #define VHOST_MAX_QUEUE_PAIRS VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX
+ #define VHOST_SUPPORTS_MQ     (1ULL << VIRTIO_NET_F_MQ)
+#else
+ #define VHOST_MAX_QUEUE_PAIRS 1
+ #define VHOST_SUPPORTS_MQ     0
+#endif
+
 /**
  * Device structure contains all configuration information relating to the device.
  */
@@ -106,7 +121,7 @@ struct virtio_net {
        char                    ifname[IF_NAME_SZ];     /**< Name of the tap device or socket path. */
        uint32_t                virt_qp_nb;     /**< number of queue pair we have allocated */
        void                    *priv;          /**< private context */
-       struct vhost_virtqueue  *virtqueue[VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX];    /**< Contains all virtqueue information. */
+       struct vhost_virtqueue  *virtqueue[VHOST_MAX_QUEUE_PAIRS * 2];  /**< Contains all virtqueue information. */
 } __rte_cache_aligned;
 
 /**

diff --git a/lib/librte_vhost/vhost_user/vhost-net-user.c b/lib/librte_vhost/vhost_user/vhost-net-user.c
index f681676ef604424a002794406fcb0ce0320cdc1d..2dc054763ec80ac00178001b440ed699e3c9799f 100644 (file)
--- a/lib/librte_vhost/vhost_user/vhost-net-user.c
+++ b/lib/librte_vhost/vhost_user/vhost-net-user.c
@@ -424,7 +424,7 @@ vserver_message_handler(int connfd, void *dat, int *remove)
                break;
 
        case VHOST_USER_GET_QUEUE_NUM:
-               msg.payload.u64 = VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX;
+               msg.payload.u64 = VHOST_MAX_QUEUE_PAIRS;
                msg.size = sizeof(msg.payload.u64);
                send_vhost_message(connfd, &msg);
                break;

diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
index 97213c5415e9f9a8386ff3da0605c269ac0f258d..3e82605cecce2af580eaa4fa118f31a9822fd4a3 100644 (file)
--- a/lib/librte_vhost/virtio-net.c
+++ b/lib/librte_vhost/virtio-net.c
@@ -74,7 +74,7 @@ static struct virtio_net_config_ll *ll_root;
 #define VHOST_SUPPORTED_FEATURES ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | \
                                (1ULL << VIRTIO_NET_F_CTRL_VQ) | \
                                (1ULL << VIRTIO_NET_F_CTRL_RX) | \
-                               (1ULL << VIRTIO_NET_F_MQ)      | \
+                               (VHOST_SUPPORTS_MQ)            | \
                                (1ULL << VHOST_F_LOG_ALL)      | \
                                (1ULL << VHOST_USER_F_PROTOCOL_FEATURES))
 static uint64_t VHOST_FEATURES = VHOST_SUPPORTED_FEATURES;