diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 0db0ec6b0a96..6c3eab485249 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -951,6 +951,40 @@ static int tcp_downgrade_zcopy_pure(struct sock *sk, struct sk_buff *skb) return 0; } +static int tcp_wmem_schedule(struct sock *sk, int copy) +{ + int left; + + if (likely(sk_wmem_schedule(sk, copy))) + return copy; + + /* We could be in trouble if we have nothing queued. + * Use whatever is left in sk->sk_forward_alloc and tcp_wmem[0] + * to guarantee some progress. + */ + left = sock_net(sk)->ipv4.sysctl_tcp_wmem[0] - sk->sk_wmem_queued; + if (left > 0) + sk_forced_mem_schedule(sk, min(left, copy)); + return min(copy, sk->sk_forward_alloc); +} + +static int tcp_wmem_schedule(struct sock *sk, int copy) +{ + int left; + + if (likely(sk_wmem_schedule(sk, copy))) + return copy; + + /* We could be in trouble if we have nothing queued. + * Use whatever is left in sk->sk_forward_alloc and tcp_wmem[0] + * to guarantee some progress. + */ + left = sock_net(sk)->ipv4.sysctl_tcp_wmem[0] - sk->sk_wmem_queued; + if (left > 0) + sk_forced_mem_schedule(sk, min(left, copy)); + return min(copy, sk->sk_forward_alloc); +} + static struct sk_buff *tcp_build_frag(struct sock *sk, int size_goal, int flags, struct page *page, int offset, size_t *size) { @@ -986,7 +1020,11 @@ new_segment: tcp_mark_push(tp, skb); goto new_segment; } - if (tcp_downgrade_zcopy_pure(sk, skb) || !sk_wmem_schedule(sk, copy)) + if (tcp_downgrade_zcopy_pure(sk, skb)) + return NULL; + + copy = tcp_wmem_schedule(sk, copy); + if (!copy) return NULL; if (can_coalesce) { @@ -1334,8 +1372,11 @@ new_segment: copy = min_t(int, copy, pfrag->size - pfrag->offset); - if (tcp_downgrade_zcopy_pure(sk, skb) || - !sk_wmem_schedule(sk, copy)) + if (tcp_downgrade_zcopy_pure(sk, skb)) + goto wait_for_space; + + copy = tcp_wmem_schedule(sk, copy); + if (!copy) goto wait_for_space; err = skb_copy_to_page_nocache(sk, &msg->msg_iter, skb, @@ -1362,7 +1403,8 @@ new_segment: skb_shinfo(skb)->flags |= SKBFL_PURE_ZEROCOPY; if (!skb_zcopy_pure(skb)) { - if (!sk_wmem_schedule(sk, copy)) + copy = tcp_wmem_schedule(sk, copy); + if (!copy) goto wait_for_space; } diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 8ab98e1aca67..18c913a2347a 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -3362,11 +3362,12 @@ void tcp_xmit_retransmit_queue(struct sock *sk) */ void sk_forced_mem_schedule(struct sock *sk, int size) { - int amt; + int delta, amt; - if (size <= sk->sk_forward_alloc) + delta = size - sk->sk_forward_alloc; + if (delta <= 0) return; - amt = sk_mem_pages(size); + amt = sk_mem_pages(delta); sk->sk_forward_alloc += amt << PAGE_SHIFT; sk_memory_allocated_add(sk, amt);