mptcp: preserve const qualifier in mptcp_sk()

We can change mptcp_sk() to propagate its argument const qualifier, thanks to container_of_const(). We need to change few things to avoid build errors: mptcp_set_datafin_timeout() and mptcp_rtx_head() have to accept non-const sk pointers. @msk local variable in mptcp_pending_tail() must be const. Signed-off-by: Eric Dumazet <[email protected]> Cc: Matthieu Baerts <[email protected]> Reviewed-by: Simon Horman <[email protected]> Reviewed-by: Matthieu Baerts <[email protected]> Signed-off-by: David S. Miller <[email protected]>
wafgo · Mar 18, 2023 · 403a40f · 403a40f
1 parent c7154ca
commit 403a40f
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Showing 2 changed files with 4 additions and 7 deletions.
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
@@ -459,7 +459,7 @@ static bool mptcp_pending_data_fin(struct sock *sk, u64 *seq)
 	return false;
 }
 
-static void mptcp_set_datafin_timeout(const struct sock *sk)
+static void mptcp_set_datafin_timeout(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	u32 retransmits;

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
@@ -334,10 +334,7 @@ static inline void msk_owned_by_me(const struct mptcp_sock *msk)
 	sock_owned_by_me((const struct sock *)msk);
 }
 
-static inline struct mptcp_sock *mptcp_sk(const struct sock *sk)
-{
-	return (struct mptcp_sock *)sk;
-}
+#define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk)
 
 /* the msk socket don't use the backlog, also account for the bulk
  * free memory
@@ -371,7 +368,7 @@ static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk)
 
 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk)
 {
-	struct mptcp_sock *msk = mptcp_sk(sk);
+	const struct mptcp_sock *msk = mptcp_sk(sk);
 
 	if (!msk->first_pending)
 		return NULL;
@@ -382,7 +379,7 @@ static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk)
 	return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list);
 }
 
-static inline struct mptcp_data_frag *mptcp_rtx_head(const struct sock *sk)
+static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk)
 {
 	struct mptcp_sock *msk = mptcp_sk(sk);