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author | Tom Herbert <tom@quantonium.net> | 2017-07-28 16:22:42 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2017-08-01 15:26:18 -0700 |
commit | 20bf50de3028cb15fa81e1d1e63ab6e0c85257fc (patch) | |
tree | 07618e5eb3db85d12ec764cd235d0de531c4e76e /net/core/skbuff.c | |
parent | 306b13eb3cf9515a8214bbf5d69d811371d05792 (diff) | |
download | op-kernel-dev-20bf50de3028cb15fa81e1d1e63ab6e0c85257fc.zip op-kernel-dev-20bf50de3028cb15fa81e1d1e63ab6e0c85257fc.tar.gz |
skbuff: Function to send an skbuf on a socket
Add skb_send_sock to send an skbuff on a socket within the kernel.
Arguments include an offset so that an skbuf might be sent in mulitple
calls (e.g. send buffer limit is hit).
Signed-off-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/skbuff.c')
-rw-r--r-- | net/core/skbuff.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index c27da51..9c0e015 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1982,6 +1982,107 @@ int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset, } EXPORT_SYMBOL_GPL(skb_splice_bits); +/* Send skb data on a socket. Socket must be locked. */ +int skb_send_sock_locked(struct sock *sk, struct sk_buff *skb, int offset, + int len) +{ + unsigned int orig_len = len; + struct sk_buff *head = skb; + unsigned short fragidx; + int slen, ret; + +do_frag_list: + + /* Deal with head data */ + while (offset < skb_headlen(skb) && len) { + struct kvec kv; + struct msghdr msg; + + slen = min_t(int, len, skb_headlen(skb) - offset); + kv.iov_base = skb->data + offset; + kv.iov_len = len; + memset(&msg, 0, sizeof(msg)); + + ret = kernel_sendmsg_locked(sk, &msg, &kv, 1, slen); + if (ret <= 0) + goto error; + + offset += ret; + len -= ret; + } + + /* All the data was skb head? */ + if (!len) + goto out; + + /* Make offset relative to start of frags */ + offset -= skb_headlen(skb); + + /* Find where we are in frag list */ + for (fragidx = 0; fragidx < skb_shinfo(skb)->nr_frags; fragidx++) { + skb_frag_t *frag = &skb_shinfo(skb)->frags[fragidx]; + + if (offset < frag->size) + break; + + offset -= frag->size; + } + + for (; len && fragidx < skb_shinfo(skb)->nr_frags; fragidx++) { + skb_frag_t *frag = &skb_shinfo(skb)->frags[fragidx]; + + slen = min_t(size_t, len, frag->size - offset); + + while (slen) { + ret = kernel_sendpage_locked(sk, frag->page.p, + frag->page_offset + offset, + slen, MSG_DONTWAIT); + if (ret <= 0) + goto error; + + len -= ret; + offset += ret; + slen -= ret; + } + + offset = 0; + } + + if (len) { + /* Process any frag lists */ + + if (skb == head) { + if (skb_has_frag_list(skb)) { + skb = skb_shinfo(skb)->frag_list; + goto do_frag_list; + } + } else if (skb->next) { + skb = skb->next; + goto do_frag_list; + } + } + +out: + return orig_len - len; + +error: + return orig_len == len ? ret : orig_len - len; +} +EXPORT_SYMBOL_GPL(skb_send_sock_locked); + +/* Send skb data on a socket. */ +int skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, int len) +{ + int ret = 0; + + lock_sock(sk); + ret = skb_send_sock_locked(sk, skb, offset, len); + release_sock(sk); + + return ret; +} +EXPORT_SYMBOL_GPL(skb_send_sock); + /** * skb_store_bits - store bits from kernel buffer to skb * @skb: destination buffer |