/* 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 = slen;
		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;
 
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:

	 
	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 = slen;
		memset(&msg, 0, sizeof(msg));

		ret = kernel_sendmsg_locked(sk, &msg, &kv, 1, slen);
		if (ret <= 0)
			goto error;

		offset += ret;
		len -= ret;
	}

	 
	if (!len)
		goto out;

	 
	offset -= skb_headlen(skb);

	 
	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) {
		 

		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;