sample/bpf: fix erspan metadata

The commit c69de58b ("net: erspan: use bitfield instead of
mask and offset") changes the erspan header to use bitfield, and
commit d350a823 ("net: erspan: create erspan metadata uapi header")
creates a uapi header file.  The above two commit breaks the current
erspan test.  This patch fixes it by adapting the above two changes.

Fixes: ac80c2a1 ("samples/bpf: add erspan v2 sample code")
Fixes: ef88f89c ("samples/bpf: extend test_tunnel_bpf.sh with ERSPAN")
Signed-off-by: NWilliam Tu <u9012063@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

samples/bpf/tcbpf2_kern.c

@@ -15,6 +15,7 @@
 #include <uapi/linux/tcp.h>
 #include <uapi/linux/filter.h>
 #include <uapi/linux/pkt_cls.h>
+#include <uapi/linux/erspan.h>
 #include <net/ipv6.h>
 #include "bpf_helpers.h"
 #include "bpf_endian.h"
@@ -35,24 +36,10 @@ struct geneve_opt {
 	u8	opt_data[8]; /* hard-coded to 8 byte */
 };
 
-struct erspan_md2 {
-	__be32 timestamp;
-	__be16 sgt;
-	__be16 flags;
-};
-
 struct vxlan_metadata {
 	u32     gbp;
 };
 
-struct erspan_metadata {
-	union {
-		__be32 index;
-		struct erspan_md2 md2;
-	} u;
-	int version;
-};
-
 SEC("gre_set_tunnel")
 int _gre_set_tunnel(struct __sk_buff *skb)
 {
@@ -156,13 +143,15 @@ int _erspan_set_tunnel(struct __sk_buff *skb)
 	__builtin_memset(&md, 0, sizeof(md));
 #ifdef ERSPAN_V1
 	md.version = 1;
-	md.u.index = htonl(123);
+	md.u.index = bpf_htonl(123);
 #else
 	u8 direction = 1;
-	u16 hwid = 7;
+	u8 hwid = 7;
 
 	md.version = 2;
-	md.u.md2.flags = htons((direction << 3) | (hwid << 4));
+	md.u.md2.dir = direction;
+	md.u.md2.hwid = hwid & 0xf;
+	md.u.md2.hwid_upper = (hwid >> 4) & 0x3;
 #endif
 
 	ret = bpf_skb_set_tunnel_opt(skb, &md, sizeof(md));
@@ -207,9 +196,9 @@ int _erspan_get_tunnel(struct __sk_buff *skb)
 	char fmt2[] = "\tdirection %d hwid %x timestamp %u\n";
 
 	bpf_trace_printk(fmt2, sizeof(fmt2),
-		(ntohs(md.u.md2.flags) >> 3) & 0x1,
-		(ntohs(md.u.md2.flags) >> 4) & 0x3f,
-		bpf_ntohl(md.u.md2.timestamp));
+			 md.u.md2.dir,
+			 (md.u.md2.hwid_upper << 4) + md.u.md2.hwid,
+			 bpf_ntohl(md.u.md2.timestamp));
 #endif
 
 	return TC_ACT_OK;
@@ -242,10 +231,12 @@ int _ip4ip6erspan_set_tunnel(struct __sk_buff *skb)
 	md.version = 1;
 #else
 	u8 direction = 0;
-	u16 hwid = 17;
+	u8 hwid = 17;
 
 	md.version = 2;
-	md.u.md2.flags = htons((direction << 3) | (hwid << 4));
+	md.u.md2.dir = direction;
+	md.u.md2.hwid = hwid & 0xf;
+	md.u.md2.hwid_upper = (hwid >> 4) & 0x3;
 #endif
 
 	ret = bpf_skb_set_tunnel_opt(skb, &md, sizeof(md));
@@ -290,9 +281,9 @@ int _ip4ip6erspan_get_tunnel(struct __sk_buff *skb)
 	char fmt2[] = "\tdirection %d hwid %x timestamp %u\n";
 
 	bpf_trace_printk(fmt2, sizeof(fmt2),
-		(ntohs(md.u.md2.flags) >> 3) & 0x1,
-		(ntohs(md.u.md2.flags) >> 4) & 0x3f,
-		bpf_ntohl(md.u.md2.timestamp));
+			 md.u.md2.dir,
+			 (md.u.md2.hwid_upper << 4) + md.u.md2.hwid,
+			 bpf_ntohl(md.u.md2.timestamp));
 #endif
 
 	return TC_ACT_OK;

samples/bpf/test_tunnel_bpf.sh

@@ -68,7 +68,7 @@ function add_erspan_tunnel {
 		ip netns exec at_ns0 \
 		ip link add dev $DEV_NS type $TYPE seq key 2 \
 		local 172.16.1.100 remote 172.16.1.200 \
-		erspan_ver 2 erspan_dir 1 erspan_hwid 3
+		erspan_ver 2 erspan_dir egress erspan_hwid 3
 	fi
 	ip netns exec at_ns0 ip link set dev $DEV_NS up
 	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
@@ -97,7 +97,7 @@ function add_ip6erspan_tunnel {
 		ip netns exec at_ns0 \
 		ip link add dev $DEV_NS type $TYPE seq key 2 \
 		local ::11 remote ::22 \
-		erspan_ver 2 erspan_dir 1 erspan_hwid 7
+		erspan_ver 2 erspan_dir egress erspan_hwid 7
 	fi
 	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
 	ip netns exec at_ns0 ip link set dev $DEV_NS up