bpf: sockmap: Merge sockmap and sockhash update functions

Merge the two very similar functions sock_map_update_elem and
sock_hash_update_elem into one.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200821102948.21918-3-lmb@cloudflare.com

net/core/sock_map.c

@@ -559,10 +559,12 @@ static bool sock_map_sk_state_allowed(const struct sock *sk)
 	return false;
 }
 
+static int sock_hash_update_common(struct bpf_map *map, void *key,
+				   struct sock *sk, u64 flags);
+
 static int sock_map_update_elem(struct bpf_map *map, void *key,
 				void *value, u64 flags)
 {
-	u32 idx = *(u32 *)key;
 	struct socket *sock;
 	struct sock *sk;
 	int ret;
@@ -591,8 +593,10 @@ static int sock_map_update_elem(struct bpf_map *map, void *key,
 	sock_map_sk_acquire(sk);
 	if (!sock_map_sk_state_allowed(sk))
 		ret = -EOPNOTSUPP;
+	else if (map->map_type == BPF_MAP_TYPE_SOCKMAP)
+		ret = sock_map_update_common(map, *(u32 *)key, sk, flags);
 	else
-		ret = sock_map_update_common(map, idx, sk, flags);
+		ret = sock_hash_update_common(map, key, sk, flags);
 	sock_map_sk_release(sk);
 out:
 	fput(sock->file);
@@ -909,45 +913,6 @@ static int sock_hash_update_common(struct bpf_map *map, void *key,
 	return ret;
 }
 
-static int sock_hash_update_elem(struct bpf_map *map, void *key,
-				 void *value, u64 flags)
-{
-	struct socket *sock;
-	struct sock *sk;
-	int ret;
-	u64 ufd;
-
-	if (map->value_size == sizeof(u64))
-		ufd = *(u64 *)value;
-	else
-		ufd = *(u32 *)value;
-	if (ufd > S32_MAX)
-		return -EINVAL;
-
-	sock = sockfd_lookup(ufd, &ret);
-	if (!sock)
-		return ret;
-	sk = sock->sk;
-	if (!sk) {
-		ret = -EINVAL;
-		goto out;
-	}
-	if (!sock_map_sk_is_suitable(sk)) {
-		ret = -EOPNOTSUPP;
-		goto out;
-	}
-
-	sock_map_sk_acquire(sk);
-	if (!sock_map_sk_state_allowed(sk))
-		ret = -EOPNOTSUPP;
-	else
-		ret = sock_hash_update_common(map, key, sk, flags);
-	sock_map_sk_release(sk);
-out:
-	fput(sock->file);
-	return ret;
-}
-
 static int sock_hash_get_next_key(struct bpf_map *map, void *key,
 				  void *key_next)
 {
@@ -1216,7 +1181,7 @@ const struct bpf_map_ops sock_hash_ops = {
 	.map_alloc		= sock_hash_alloc,
 	.map_free		= sock_hash_free,
 	.map_get_next_key	= sock_hash_get_next_key,
-	.map_update_elem	= sock_hash_update_elem,
+	.map_update_elem	= sock_map_update_elem,
 	.map_delete_elem	= sock_hash_delete_elem,
 	.map_lookup_elem	= sock_hash_lookup,
 	.map_lookup_elem_sys_only = sock_hash_lookup_sys,