net: update consumers of MSG_MORE to recognize MSG_SENDPAGE_NOTLAST

Commit 35f9c09fe (tcp: tcp_sendpages() should call tcp_push() once)
added an internal flag MSG_SENDPAGE_NOTLAST, similar to
MSG_MORE.

algif_hash, algif_skcipher, and udp used MSG_MORE from tcp_sendpages()
and need to see the new flag as identical to MSG_MORE.

This fixes sendfile() on AF_ALG.

v3: also fix udp

Cc: Tom Herbert <therbert@google.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: <stable@vger.kernel.org> # 3.4.x + 3.2.x
Reported-and-tested-by: Shawn Landden <shawnlandden@gmail.com>
Original-patch: Richard Weinberger <richard@nod.at>
Signed-off-by: Shawn Landden <shawn@churchofgit.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

crypto/algif_hash.c

@@ -114,6 +114,9 @@ static ssize_t hash_sendpage(struct socket *sock, struct page *page,
 	struct hash_ctx *ctx = ask->private;
 	int err;
 
+	if (flags & MSG_SENDPAGE_NOTLAST)
+		flags |= MSG_MORE;
+
 	lock_sock(sk);
 	sg_init_table(ctx->sgl.sg, 1);
 	sg_set_page(ctx->sgl.sg, page, size, offset);

crypto/algif_skcipher.c

@@ -378,6 +378,9 @@ static ssize_t skcipher_sendpage(struct socket *sock, struct page *page,
 	struct skcipher_sg_list *sgl;
 	int err = -EINVAL;
 
+	if (flags & MSG_SENDPAGE_NOTLAST)
+		flags |= MSG_MORE;
+
 	lock_sock(sk);
 	if (!ctx->more && ctx->used)
 		goto unlock;

net/ipv4/udp.c

@@ -1098,6 +1098,9 @@ int udp_sendpage(struct sock *sk, struct page *page, int offset,
 	struct udp_sock *up = udp_sk(sk);
 	int ret;
 
+	if (flags & MSG_SENDPAGE_NOTLAST)
+		flags |= MSG_MORE;
+
 	if (!up->pending) {
 		struct msghdr msg = {	.msg_flags = flags|MSG_MORE };