From 2e4e44107176d552f8bb1bb76053e850e3809841 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 17 Sep 2014 04:49:49 -0700 Subject: net: add alloc_skb_with_frags() helper Extract from sock_alloc_send_pskb() code building skb with frags, so that we can reuse this in other contexts. Intent is to use it from tcp_send_rcvq(), tcp_collapse(), ... We also want to replace some skb_linearize() calls to a more reliable strategy in pathological cases where we need to reduce number of frags. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/sock.c | 78 +++++++++++---------------------------------------------- 1 file changed, 15 insertions(+), 63 deletions(-) (limited to 'net/core/sock.c') diff --git a/net/core/sock.c b/net/core/sock.c index 6f436b5e4961..de887c45c63b 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1762,21 +1762,12 @@ struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, unsigned long data_len, int noblock, int *errcode, int max_page_order) { - struct sk_buff *skb = NULL; - unsigned long chunk; - gfp_t gfp_mask; + struct sk_buff *skb; long timeo; int err; - int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; - struct page *page; - int i; - - err = -EMSGSIZE; - if (npages > MAX_SKB_FRAGS) - goto failure; timeo = sock_sndtimeo(sk, noblock); - while (!skb) { + for (;;) { err = sock_error(sk); if (err != 0) goto failure; @@ -1785,66 +1776,27 @@ struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, if (sk->sk_shutdown & SEND_SHUTDOWN) goto failure; - if (atomic_read(&sk->sk_wmem_alloc) >= sk->sk_sndbuf) { - set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); - set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); - err = -EAGAIN; - if (!timeo) - goto failure; - if (signal_pending(current)) - goto interrupted; - timeo = sock_wait_for_wmem(sk, timeo); - continue; - } - - err = -ENOBUFS; - gfp_mask = sk->sk_allocation; - if (gfp_mask & __GFP_WAIT) - gfp_mask |= __GFP_REPEAT; + if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf) + break; - skb = alloc_skb(header_len, gfp_mask); - if (!skb) + set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); + set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); + err = -EAGAIN; + if (!timeo) goto failure; - - skb->truesize += data_len; - - for (i = 0; npages > 0; i++) { - int order = max_page_order; - - while (order) { - if (npages >= 1 << order) { - page = alloc_pages(sk->sk_allocation | - __GFP_COMP | - __GFP_NOWARN | - __GFP_NORETRY, - order); - if (page) - goto fill_page; - /* Do not retry other high order allocations */ - order = 1; - max_page_order = 0; - } - order--; - } - page = alloc_page(sk->sk_allocation); - if (!page) - goto failure; -fill_page: - chunk = min_t(unsigned long, data_len, - PAGE_SIZE << order); - skb_fill_page_desc(skb, i, page, 0, chunk); - data_len -= chunk; - npages -= 1 << order; - } + if (signal_pending(current)) + goto interrupted; + timeo = sock_wait_for_wmem(sk, timeo); } - - skb_set_owner_w(skb, sk); + skb = alloc_skb_with_frags(header_len, data_len, max_page_order, + errcode, sk->sk_allocation); + if (skb) + skb_set_owner_w(skb, sk); return skb; interrupted: err = sock_intr_errno(timeo); failure: - kfree_skb(skb); *errcode = err; return NULL; } -- cgit v1.2.3-55-g7522