diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 5fa66db0cb5d76b5fb9e87a3b0f67a089562f829..03cff88c72920876664ba923bc6995b1f0258537 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -848,6 +848,27 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev, struct sk_buff *skb, struct net_device *sb_dev); +enum net_device_path_type { + DEV_PATH_ETHERNET = 0, +}; + +struct net_device_path { + enum net_device_path_type type; + const struct net_device *dev; +}; + +#define NET_DEVICE_PATH_STACK_MAX 5 + +struct net_device_path_stack { + int num_paths; + struct net_device_path path[NET_DEVICE_PATH_STACK_MAX]; +}; + +struct net_device_path_ctx { + const struct net_device *dev; + const u8 *daddr; +}; + enum tc_setup_type { TC_SETUP_QDISC_MQPRIO, TC_SETUP_CLSU32, @@ -1282,6 +1303,8 @@ struct netdev_net_notifier { * struct net_device *(*ndo_get_peer_dev)(struct net_device *dev); * If a device is paired with a peer device, return the peer instance. * The caller must be under RCU read context. + * int (*ndo_fill_forward_path)(struct net_device_path_ctx *ctx, struct net_device_path *path); + * Get the forwarding path to reach the real device from the HW destination address */ struct net_device_ops { int (*ndo_init)(struct net_device *dev); @@ -1488,6 +1511,8 @@ struct net_device_ops { int (*ndo_tunnel_ctl)(struct net_device *dev, struct ip_tunnel_parm *p, int cmd); struct net_device * (*ndo_get_peer_dev)(struct net_device *dev); + int (*ndo_fill_forward_path)(struct net_device_path_ctx *ctx, + struct net_device_path *path); }; /** @@ -2870,6 +2895,8 @@ void dev_remove_offload(struct packet_offload *po); int dev_get_iflink(const struct net_device *dev); int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb); +int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, + struct net_device_path_stack *stack); struct net_device *__dev_get_by_flags(struct net *net, unsigned short flags, unsigned short mask); struct net_device *dev_get_by_name(struct net *net, const char *name); diff --git a/net/core/dev.c b/net/core/dev.c index 515309573cb8cab0129a244fa5ad75021ffafcfa..4bb6dcdbed8b856c03dc4af8b7fafe08984e803f 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -848,6 +848,52 @@ int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) } EXPORT_SYMBOL_GPL(dev_fill_metadata_dst); +static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack) +{ + int k = stack->num_paths++; + + if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX)) + return NULL; + + return &stack->path[k]; +} + +int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, + struct net_device_path_stack *stack) +{ + const struct net_device *last_dev; + struct net_device_path_ctx ctx = { + .dev = dev, + .daddr = daddr, + }; + struct net_device_path *path; + int ret = 0; + + stack->num_paths = 0; + while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) { + last_dev = ctx.dev; + path = dev_fwd_path(stack); + if (!path) + return -1; + + memset(path, 0, sizeof(struct net_device_path)); + ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path); + if (ret < 0) + return -1; + + if (WARN_ON_ONCE(last_dev == ctx.dev)) + return -1; + } + path = dev_fwd_path(stack); + if (!path) + return -1; + path->type = DEV_PATH_ETHERNET; + path->dev = ctx.dev; + + return ret; +} +EXPORT_SYMBOL_GPL(dev_fill_forward_path); + /** * __dev_get_by_name - find a device by its name * @net: the applicable net namespace