macvtap: Implement multiqueue for macvtap driver

Implement multiqueue facility for macvtap driver. The idea is that
a macvtap device can be opened multiple times and the fd's can be
used to register eg, as backend for vhost.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 1 deletions

diff --git a/include/linux/if_macvlan.h b/include/linux/if_macvlan.h
index 35280b302290..8a2fd66a8b5f 100644
--- a/include/linux/if_macvlan.h
+++ b/include/linux/if_macvlan.h
@@ -40,6 +40,12 @@ struct macvlan_rx_stats {
         unsigned long           rx_errors;
 };
 
+/*
+ * Maximum times a macvtap device can be opened. This can be used to
+ * configure the number of receive queue, e.g. for multiqueue virtio.
+ */
+#define MAX_MACVTAP_QUEUES      (NR_CPUS < 16 ? NR_CPUS : 16)
+
 struct macvlan_dev {
         struct net_device       *dev;
         struct list_head        list;
@@ -50,7 +56,8 @@ struct macvlan_dev {
         enum macvlan_mode       mode;
         int (*receive)(struct sk_buff *skb);
         int (*forward)(struct net_device *dev, struct sk_buff *skb);
-        struct macvtap_queue    *tap;
+        struct macvtap_queue    *taps[MAX_MACVTAP_QUEUES];
+        int                     numvtaps;
 };
 
 static inline void macvlan_count_rx(const struct macvlan_dev *vlan,