net: allow better page reuse in splice(sock -> pipe)

splice() from socket to pipe needs linear_to_page() helper to transfert
skb header to part of page.

We can reset the offset in the current sk->sk_sndmsg_page if we are the
last user of the page.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2012-04-19 09:38:17 +00:00 коммит произвёл David S. Miller
Родитель acd6996234
Коммит e66e9a3147
1 изменённых файлов: 3 добавлений и 0 удалений

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@ -1565,6 +1565,9 @@ new_page:
} else {
unsigned int mlen;
/* If we are the only user of the page, we can reset offset */
if (page_count(p) == 1)
sk->sk_sndmsg_off = 0;
off = sk->sk_sndmsg_off;
mlen = PAGE_SIZE - off;
if (mlen < 64 && mlen < *len) {