net: skb_copy_datagram_const_iovec()
There's an skb_copy_datagram_iovec() to copy out of a paged skb,
but it modifies the iovec, and does not support starting
at an offset in the destination. We want both in tun.c, so let's
add the function.
It's a carbon copy of skb_copy_datagram_iovec() with enough changes to
be annoying.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/socket.h b/include/linux/socket.h
index 421afb4..171b08d 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -318,6 +318,8 @@
extern int verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr *address, int mode);
extern int memcpy_toiovec(struct iovec *v, unsigned char *kdata, int len);
+extern int memcpy_toiovecend(const struct iovec *v, unsigned char *kdata,
+ int offset, int len);
extern int move_addr_to_user(struct sockaddr *kaddr, int klen, void __user *uaddr, int __user *ulen);
extern int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr *kaddr);
extern int put_cmsg(struct msghdr*, int level, int type, int len, void *data);