[PATCH net-next 1/3] net: constify sk_skb_reason_drop() sock parameter

[Eric Dumazet <edumazet@google.com>]

sk_skb_reason_drop() does not change sock parameter, make it
const so that we can call it from TCP stack without a cast
on a (const) listener socket.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/linux/skbuff.h     | 3 ++-
 include/trace/events/skb.h | 4 ++--
 net/core/skbuff.c          | 5 +++--
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 2bcf78a4de7b9edb0d1342319d4340c0a9997eeb..746e741a8ef99b3052ad581650e5d0db2a95dbb3 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1313,7 +1313,8 @@ static inline bool skb_data_unref(const struct sk_buff *skb,
 	return true;
 }
 
-void __fix_address sk_skb_reason_drop(struct sock *sk, struct sk_buff *skb,
+void __fix_address sk_skb_reason_drop(const struct sock *sk,
+				      struct sk_buff *skb,
 				      enum skb_drop_reason reason);
 
 static inline void
diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h
index b877133cd93a80f6b130fab64f334ecdeab8c8fd..2945aa7fe9a7ded5bdec5be3a67382de95239517 100644
--- a/include/trace/events/skb.h
+++ b/include/trace/events/skb.h
@@ -24,14 +24,14 @@ DEFINE_DROP_REASON(FN, FN)
 TRACE_EVENT(kfree_skb,
 
 	TP_PROTO(struct sk_buff *skb, void *location,
-		 enum skb_drop_reason reason, struct sock *rx_sk),
+		 enum skb_drop_reason reason, const struct sock *rx_sk),
 
 	TP_ARGS(skb, location, reason, rx_sk),
 
 	TP_STRUCT__entry(
 		__field(void *,		skbaddr)
 		__field(void *,		location)
-		__field(void *,		rx_sk)
+		__field(const void *,	rx_sk)
 		__field(unsigned short,	protocol)
 		__field(enum skb_drop_reason,	reason)
 	),
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 7dad68e3b5186cf622a3ed5a6e87c09d46bc3fd6..acca1365672c4f98b004c2548133d70c9cf5ddc1 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -1206,7 +1206,7 @@ void __kfree_skb(struct sk_buff *skb)
 EXPORT_SYMBOL(__kfree_skb);
 
 static __always_inline
-bool __sk_skb_reason_drop(struct sock *sk, struct sk_buff *skb,
+bool __sk_skb_reason_drop(const struct sock *sk, struct sk_buff *skb,
 			  enum skb_drop_reason reason)
 {
 	if (unlikely(!skb_unref(skb)))
@@ -1235,7 +1235,8 @@ bool __sk_skb_reason_drop(struct sock *sk, struct sk_buff *skb,
  *	'kfree_skb' tracepoint.
  */
 void __fix_address
-sk_skb_reason_drop(struct sock *sk, struct sk_buff *skb, enum skb_drop_reason reason)
+sk_skb_reason_drop(const struct sock *sk, struct sk_buff *skb,
+		   enum skb_drop_reason reason)
 {
 	if (__sk_skb_reason_drop(sk, skb, reason))
 		__kfree_skb(skb);
-- 
2.54.0.563.g4f69b47b94-goog