diff options
| -rw-r--r-- | net/kcm/kcmsock.c | 147 |
1 files changed, 145 insertions, 2 deletions
diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index 982ea5f77bfc..9ac24995691c 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -990,6 +990,149 @@ static void kcm_push(struct kcm_sock *kcm) kcm_write_msgs(kcm); } +static ssize_t kcm_sendpage(struct socket *sock, struct page *page, + int offset, size_t size, int flags) + +{ + struct sock *sk = sock->sk; + struct kcm_sock *kcm = kcm_sk(sk); + struct sk_buff *skb = NULL, *head = NULL; + long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); + bool eor; + int err = 0; + int i; + + if (flags & MSG_SENDPAGE_NOTLAST) + flags |= MSG_MORE; + + /* No MSG_EOR from splice, only look at MSG_MORE */ + eor = !(flags & MSG_MORE); + + lock_sock(sk); + + sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); + + err = -EPIPE; + if (sk->sk_err) + goto out_error; + + if (kcm->seq_skb) { + /* Previously opened message */ + head = kcm->seq_skb; + skb = kcm_tx_msg(head)->last_skb; + i = skb_shinfo(skb)->nr_frags; + + if (skb_can_coalesce(skb, i, page, offset)) { + skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], size); + skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; + goto coalesced; + } + + if (i >= MAX_SKB_FRAGS) { + struct sk_buff *tskb; + + tskb = alloc_skb(0, sk->sk_allocation); + while (!tskb) { + kcm_push(kcm); + err = sk_stream_wait_memory(sk, &timeo); + if (err) + goto out_error; + } + + if (head == skb) + skb_shinfo(head)->frag_list = tskb; + else + skb->next = tskb; + + skb = tskb; + skb->ip_summed = CHECKSUM_UNNECESSARY; + i = 0; + } + } else { + /* Call the sk_stream functions to manage the sndbuf mem. */ + if (!sk_stream_memory_free(sk)) { + kcm_push(kcm); + set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); + err = sk_stream_wait_memory(sk, &timeo); + if (err) + goto out_error; + } + + head = alloc_skb(0, sk->sk_allocation); + while (!head) { + kcm_push(kcm); + err = sk_stream_wait_memory(sk, &timeo); + if (err) + goto out_error; + } + + skb = head; + i = 0; + } + + get_page(page); + skb_fill_page_desc(skb, i, page, offset, size); + skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; + +coalesced: + skb->len += size; + skb->data_len += size; + skb->truesize += size; + sk->sk_wmem_queued += size; + sk_mem_charge(sk, size); + + if (head != skb) { + head->len += size; + head->data_len += size; + head->truesize += size; + } + + if (eor) { + bool not_busy = skb_queue_empty(&sk->sk_write_queue); + + /* Message complete, queue it on send buffer */ + __skb_queue_tail(&sk->sk_write_queue, head); + kcm->seq_skb = NULL; + KCM_STATS_INCR(kcm->stats.tx_msgs); + + if (flags & MSG_BATCH) { + kcm->tx_wait_more = true; + } else if (kcm->tx_wait_more || not_busy) { + err = kcm_write_msgs(kcm); + if (err < 0) { + /* We got a hard error in write_msgs but have + * already queued this message. Report an error + * in the socket, but don't affect return value + * from sendmsg + */ + pr_warn("KCM: Hard failure on kcm_write_msgs\n"); + report_csk_error(&kcm->sk, -err); + } + } + } else { + /* Message not complete, save state */ + kcm->seq_skb = head; + kcm_tx_msg(head)->last_skb = skb; + } + + KCM_STATS_ADD(kcm->stats.tx_bytes, size); + + release_sock(sk); + return size; + +out_error: + kcm_push(kcm); + + err = sk_stream_error(sk, flags, err); + + /* make sure we wake any epoll edge trigger waiter */ + if (unlikely(skb_queue_len(&sk->sk_write_queue) == 0 && err == -EAGAIN)) + sk->sk_write_space(sk); + + release_sock(sk); + return err; +} + static int kcm_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) { struct sock *sk = sock->sk; @@ -1995,7 +2138,7 @@ static const struct proto_ops kcm_dgram_ops = { .sendmsg = kcm_sendmsg, .recvmsg = kcm_recvmsg, .mmap = sock_no_mmap, - .sendpage = sock_no_sendpage, + .sendpage = kcm_sendpage, }; static const struct proto_ops kcm_seqpacket_ops = { @@ -2016,7 +2159,7 @@ static const struct proto_ops kcm_seqpacket_ops = { .sendmsg = kcm_sendmsg, .recvmsg = kcm_recvmsg, .mmap = sock_no_mmap, - .sendpage = sock_no_sendpage, + .sendpage = kcm_sendpage, .splice_read = kcm_splice_read, }; |