From e5a4b0bb803b39a36478451eae53a880d2663d5b Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 24 Nov 2014 18:17:55 -0500 Subject: switch memcpy_to_msg() and skb_copy{,_and_csum}_datagram_msg() to primitives ... making both non-draining. That means that tcp_recvmsg() becomes non-draining. And _that_ would break iscsit_do_rx_data() unless we a) make sure tcp_recvmsg() is uniformly non-draining (it is) b) make sure it copes with arbitrary (including shifted) iov_iter (it does, all it uses is iov_iter primitives) c) make iscsit_do_rx_data() initialize ->msg_iter only once. Fortunately, (c) is doable with minimal work and we are rid of one the two places where kernel send/recvmsg users would be unhappy with non-draining behaviour. Actually, that makes all but one of ->recvmsg() instances iov_iter-clean. The exception is skcipher_recvmsg() and it also isn't hard to convert to primitives (iov_iter_get_pages() is needed there). That'll wait a bit - there's some interplay with ->sendmsg() path for that one. Signed-off-by: Al Viro --- include/linux/skbuff.h | 16 ++++------------ 1 file changed, 4 insertions(+), 12 deletions(-) (limited to 'include/linux/skbuff.h') diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 52cf1bdac0d8..4902f2df90c8 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -2651,17 +2651,10 @@ int skb_copy_datagram_iter(const struct sk_buff *from, int offset, static inline int skb_copy_datagram_msg(const struct sk_buff *from, int offset, struct msghdr *msg, int size) { - /* XXX: stripping const */ - return skb_copy_datagram_iovec(from, offset, (struct iovec *)msg->msg_iter.iov, size); -} -int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb, int hlen, - struct iovec *iov); -static inline int skb_copy_and_csum_datagram_msg(struct sk_buff *skb, int hlen, - struct msghdr *msg) -{ - /* XXX: stripping const */ - return skb_copy_and_csum_datagram_iovec(skb, hlen, (struct iovec *)msg->msg_iter.iov); + return skb_copy_datagram_iter(from, offset, &msg->msg_iter, size); } +int skb_copy_and_csum_datagram_msg(struct sk_buff *skb, int hlen, + struct msghdr *msg); int skb_copy_datagram_from_iter(struct sk_buff *skb, int offset, struct iov_iter *from, int len); int zerocopy_sg_from_iter(struct sk_buff *skb, struct iov_iter *frm); @@ -2697,8 +2690,7 @@ static inline int memcpy_from_msg(void *data, struct msghdr *msg, int len) static inline int memcpy_to_msg(struct msghdr *msg, void *data, int len) { - /* XXX: stripping const */ - return memcpy_toiovec((struct iovec *)msg->msg_iter.iov, data, len); + return copy_to_iter(data, len, &msg->msg_iter) == len ? 0 : -EFAULT; } struct skb_checksum_ops { -- cgit v1.2.1