Commit 264ba53f authored by David Howells's avatar David Howells Committed by Jakub Kicinski
Browse files

kcm: Use sendmsg(MSG_SPLICE_PAGES) rather then sendpage 



When transmitting data, call down into the transport socket using sendmsg
with MSG_SPLICE_PAGES to indicate that content should be spliced rather
than using sendpage.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
cc: Tom Herbert <tom@herbertland.com>
cc: Tom Herbert <tom@quantonium.net>
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent de17c685

net/kcm/kcmsock.c

+11 −5
Original line number Diff line number Diff line
@@ -641,6 +641,10 @@ static int kcm_write_msgs(struct kcm_sock *kcm) 


		for (fragidx = 0; fragidx < skb_shinfo(skb)->nr_frags;

		     fragidx++) {

			struct bio_vec bvec;

			struct msghdr msg = {

				.msg_flags = MSG_DONTWAIT | MSG_SPLICE_PAGES,

			};

			skb_frag_t *frag;



			frag_offset = 0;
@@ -651,11 +655,13 @@ static int kcm_write_msgs(struct kcm_sock *kcm) 
				goto out;

			}



			ret = kernel_sendpage(psock->sk->sk_socket,

			bvec_set_page(&bvec,

				      skb_frag_page(frag),

					      skb_frag_off(frag) + frag_offset,

				      skb_frag_size(frag) - frag_offset,

					      MSG_DONTWAIT);

				      skb_frag_off(frag) + frag_offset);

			iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1,

				      bvec.bv_len);

			ret = sock_sendmsg(psock->sk->sk_socket, &msg);

			if (ret <= 0) {

				if (ret == -EAGAIN) {

					/* Save state to try again when there's