netdev - [PATCH net-next 5/5] net: limit scope of a skb_zerocopy_iter

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Date: Thu, 27 Jun 2024 13:59:45 +0100
From: Pavel Begunkov <asml.silence@...il.com>
To: io-uring@...r.kernel.org,
	netdev@...r.kernel.org
Cc: Jens Axboe <axboe@...nel.dk>,
	asml.silence@...il.com,
	"David S . Miller" <davem@...emloft.net>,
	Jakub Kicinski <kuba@...nel.org>,
	David Ahern <dsahern@...nel.org>,
	Eric Dumazet <edumazet@...gle.com>,
	Willem de Bruijn <willemdebruijn.kernel@...il.com>
Subject: [PATCH net-next 5/5] net: limit scope of a skb_zerocopy_iter_stream var

skb_zerocopy_iter_stream() only uses @orig_uarg in the !link_skb path,
and we can move the local variable in the appropriate block.

Signed-off-by: Pavel Begunkov <asml.silence@...il.com>
---
 net/core/skbuff.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 9f28822dde6f..9b71e4b8796a 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -1856,7 +1856,6 @@ int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb,
 			     struct msghdr *msg, int len,
 			     struct ubuf_info *uarg)
 {
-	struct ubuf_info *orig_uarg = skb_zcopy(skb);
 	int err, orig_len = skb->len;
 
 	if (uarg->ops->link_skb) {
@@ -1864,6 +1863,8 @@ int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb,
 		if (err)
 			return err;
 	} else {
+		struct ubuf_info *orig_uarg = skb_zcopy(skb);
+
 		/* An skb can only point to one uarg. This edge case happens
 		 * when TCP appends to an skb, but zerocopy_realloc triggered
 		 * a new alloc.
-- 
2.44.0