[PATCH v1 bpf-next 6/8] bpf: tcp: Factorise bpf_skops_established().

[Kuniyuki Iwashima <kuniyu@google.com>]

We will call BPF SOCK_OPS prog with BPF_SOCK_OPS_RCVLOWAT_CB.

It requires a similar setup to bpf_skops_established(), and the
only difference is the skb data length.

Let's factor out the common logic into bpf_skops_common_locked().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
---
 net/ipv4/tcp_input.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 021f745747c5..7e26503fd96d 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -179,8 +179,9 @@ static void bpf_skops_parse_hdr(struct sock *sk, struct sk_buff *skb)
 	BPF_CGROUP_RUN_PROG_SOCK_OPS(&sock_ops);
 }
 
-static void bpf_skops_established(struct sock *sk, int bpf_op,
-				  struct sk_buff *skb)
+static void bpf_skops_common_locked(struct sock *sk, int bpf_op,
+				    struct sk_buff *skb,
+				    unsigned int end_offset)
 {
 	struct bpf_sock_ops_kern sock_ops;
 
@@ -191,12 +192,18 @@ static void bpf_skops_established(struct sock *sk, int bpf_op,
 	sock_ops.is_fullsock = 1;
 	sock_ops.is_locked_tcp_sock = 1;
 	sock_ops.sk = sk;
-	/* sk with TCP_REPAIR_ON does not have skb in tcp_finish_connect */
 	if (skb)
-		bpf_skops_init_skb(&sock_ops, skb, tcp_hdrlen(skb));
+		bpf_skops_init_skb(&sock_ops, skb, end_offset);
 
 	BPF_CGROUP_RUN_PROG_SOCK_OPS(&sock_ops);
 }
+
+static void bpf_skops_established(struct sock *sk, int bpf_op,
+				  struct sk_buff *skb)
+{
+	/* sk with TCP_REPAIR_ON does not have skb in tcp_finish_connect */
+	bpf_skops_common_locked(sk, bpf_op, skb, skb ? tcp_hdrlen(skb) : 0);
+}
 #else
 static void bpf_skops_parse_hdr(struct sock *sk, struct sk_buff *skb)
 {
-- 
2.54.0.563.g4f69b47b94-goog