kernel: add linux 5.10 support

Signed-off-by: Felix Fietkau <nbd@nbd.name>

1 files changed, 170 insertions, 0 deletions

diff --git a/target/linux/generic/pending-5.10/640-02-net-resolve-forwarding-path-from-virtual-netdevice-a.patch b/target/linux/generic/pending-5.10/640-02-net-resolve-forwarding-path-from-virtual-netdevice-a.patch
new file mode 100644
index 0000000000..953446baab
--- /dev/null
+++ b/target/linux/generic/pending-5.10/640-02-net-resolve-forwarding-path-from-virtual-netdevice-a.patch
@@ -0,0 +1,170 @@
+From: Pablo Neira Ayuso <pablo@netfilter.org>
+Date: Sun, 10 Jan 2021 15:53:58 +0100
+Subject: [PATCH] net: resolve forwarding path from virtual netdevice and
+ HW destination address
+
+This patch adds dev_fill_forward_path() which resolves the path to reach
+the real netdevice from the IP forwarding side. This function takes as
+input the netdevice and the destination hardware address and it walks
+down the devices calling .ndo_fill_forward_path() for each device until
+the real device is found.
+
+For instance, assuming the following topology:
+
+               IP forwarding
+              /             \
+           br0              eth0
+           / \
+       eth1  eth2
+        .
+        .
+        .
+       ethX
+ ab:cd:ef:ab:cd:ef
+
+where eth1 and eth2 are bridge ports and eth0 provides WAN connectivity.
+ethX is the interface in another box which is connected to the eth1
+bridge port.
+
+For packets going through IP forwarding to br0 whose destination MAC
+address is ab:cd:ef:ab:cd:ef, dev_fill_forward_path() provides the
+following path:
+
+	br0 -> eth1
+
+.ndo_fill_forward_path for br0 looks up at the FDB for the bridge port
+from the destination MAC address to get the bridge port eth1.
+
+This information allows to create a fast path that bypasses the classic
+bridge and IP forwarding paths, so packets go directly from the bridge
+port eth1 to eth0 (wan interface) and vice versa.
+
+             fast path
+      .------------------------.
+     /                          \
+    |           IP forwarding   |
+    |          /             \  \/
+    |       br0               eth0
+    .       / \
+     -> eth1  eth2
+        .
+        .
+        .
+       ethX
+ ab:cd:ef:ab:cd:ef
+
+Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
+---
+
+--- a/include/linux/netdevice.h
++++ b/include/linux/netdevice.h
+@@ -833,6 +833,27 @@ typedef u16 (*select_queue_fallback_t)(s
+ 				       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,
+@@ -1279,6 +1300,8 @@ 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);
+@@ -1487,6 +1510,8 @@ 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);
+ };
+ 
+ /**
+@@ -2798,6 +2823,8 @@ void dev_remove_offload(struct packet_of
+ 
+ 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);
+--- a/net/core/dev.c
++++ b/net/core/dev.c
+@@ -846,6 +846,52 @@ int dev_fill_metadata_dst(struct net_dev
+ }
+ 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