[PATCH net-next] tipc: delete the unlikely branch in tipc_aead_encrypt
From: Xin Long <lucien.xin@gmail.com>
Date: 2021-11-24 17:11:19
Subsystem:
networking [general], the rest, tipc network layer · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Jon Maloy, Tung Quang Nguyen
When a skb comes to tipc_aead_encrypt(), it's always linear. The
unlikely check 'skb_cloned(skb) && tailen <= skb_tailroom(skb)'
can completely be taken care of in skb_cow_data() by the code
in branch "if (!skb_has_frag_list())".
Also, remove the 'TODO:' annotation, as the pages in skbs are not
writable, see more on commit 3cf4375a0904 ("tipc: do not write
skb_shinfo frags when doing decrytion").
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Jon Maloy <jmaloy@redhat.com>
---
net/tipc/crypto.c | 19 ++++---------------
1 file changed, 4 insertions(+), 15 deletions(-)
diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c
index b4d9419a015b..81116312b753 100644
--- a/net/tipc/crypto.c
+++ b/net/tipc/crypto.c@@ -761,21 +761,10 @@ static int tipc_aead_encrypt(struct tipc_aead *aead, struct sk_buff *skb, skb_tailroom(skb), tailen); } - if (unlikely(!skb_cloned(skb) && tailen <= skb_tailroom(skb))) { - nsg = 1; - trailer = skb; - } else { - /* TODO: We could avoid skb_cow_data() if skb has no frag_list - * e.g. by skb_fill_page_desc() to add another page to the skb - * with the wanted tailen... However, page skbs look not often, - * so take it easy now! - * Cloned skbs e.g. from link_xmit() seems no choice though :( - */ - nsg = skb_cow_data(skb, tailen, &trailer); - if (unlikely(nsg < 0)) { - pr_err("TX: skb_cow_data() returned %d\n", nsg); - return nsg; - } + nsg = skb_cow_data(skb, tailen, &trailer); + if (unlikely(nsg < 0)) { + pr_err("TX: skb_cow_data() returned %d\n", nsg); + return nsg; } pskb_put(skb, trailer, tailen);
--
2.27.0