skb_copy_datagram_iovec() can die

no callers other than itself.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

include/linux/skbuff.h

@@ -2644,8 +2644,6 @@ struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, int noblock,
 				  int *err);
 unsigned int datagram_poll(struct file *file, struct socket *sock,
 			   struct poll_table_struct *wait);
-int skb_copy_datagram_iovec(const struct sk_buff *from, int offset,
-			    struct iovec *to, int size);
 int skb_copy_datagram_iter(const struct sk_buff *from, int offset,
 			   struct iov_iter *to, int size);
 static inline int skb_copy_datagram_msg(const struct sk_buff *from, int offset,

net/core/datagram.c

@@ -309,90 +309,6 @@ int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags)
 }
 EXPORT_SYMBOL(skb_kill_datagram);
 
-/**
- *	skb_copy_datagram_iovec - Copy a datagram to an iovec.
- *	@skb: buffer to copy
- *	@offset: offset in the buffer to start copying from
- *	@to: io vector to copy to
- *	@len: amount of data to copy from buffer to iovec
- *
- *	Note: the iovec is modified during the copy.
- */
-int skb_copy_datagram_iovec(const struct sk_buff *skb, int offset,
-			    struct iovec *to, int len)
-{
-	int start = skb_headlen(skb);
-	int i, copy = start - offset;
-	struct sk_buff *frag_iter;
-
-	trace_skb_copy_datagram_iovec(skb, len);
-
-	/* Copy header. */
-	if (copy > 0) {
-		if (copy > len)
-			copy = len;
-		if (memcpy_toiovec(to, skb->data + offset, copy))
-			goto fault;
-		if ((len -= copy) == 0)
-			return 0;
-		offset += copy;
-	}
-
-	/* Copy paged appendix. Hmm... why does this look so complicated? */
-	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-		int end;
-		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
-
-		WARN_ON(start > offset + len);
-
-		end = start + skb_frag_size(frag);
-		if ((copy = end - offset) > 0) {
-			int err;
-			u8  *vaddr;
-			struct page *page = skb_frag_page(frag);
-
-			if (copy > len)
-				copy = len;
-			vaddr = kmap(page);
-			err = memcpy_toiovec(to, vaddr + frag->page_offset +
-					     offset - start, copy);
-			kunmap(page);
-			if (err)
-				goto fault;
-			if (!(len -= copy))
-				return 0;
-			offset += copy;
-		}
-		start = end;
-	}
-
-	skb_walk_frags(skb, frag_iter) {
-		int end;
-
-		WARN_ON(start > offset + len);
-
-		end = start + frag_iter->len;
-		if ((copy = end - offset) > 0) {
-			if (copy > len)
-				copy = len;
-			if (skb_copy_datagram_iovec(frag_iter,
-						    offset - start,
-						    to, copy))
-				goto fault;
-			if ((len -= copy) == 0)
-				return 0;
-			offset += copy;
-		}
-		start = end;
-	}
-	if (!len)
-		return 0;
-
-fault:
-	return -EFAULT;
-}
-EXPORT_SYMBOL(skb_copy_datagram_iovec);
-
 /**
  *	skb_copy_datagram_iter - Copy a datagram to an iovec iterator.
  *	@skb: buffer to copy