Commit 7d690c15 authored by Al Viro's avatar Al Viro
Browse files

iter_to_pipe(): switch to advancing variant of iov_iter_get_pages() 



... and untangle the cleanup on failure to add into pipe.

Reviewed-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 480cb846

fs/splice.c

+24 −23
Original line number Diff line number Diff line
@@ -1158,39 +1158,40 @@ static int iter_to_pipe(struct iov_iter *from, 
	};

	size_t total = 0;

	int ret = 0;

	bool failed = false;



	while (iov_iter_count(from) && !failed) {

	while (iov_iter_count(from)) {

		struct page *pages[16];

		ssize_t copied;

		ssize_t left;

		size_t start;

		int n;

		int i, n;



		copied = iov_iter_get_pages(from, pages, ~0UL, 16, &start);

		if (copied <= 0) {

			ret = copied;

		left = iov_iter_get_pages2(from, pages, ~0UL, 16, &start);

		if (left <= 0) {

			ret = left;

			break;

		}



		for (n = 0; copied; n++, start = 0) {

			int size = min_t(int, copied, PAGE_SIZE - start);

			if (!failed) {

				buf.page = pages[n];

		n = DIV_ROUND_UP(left + start, PAGE_SIZE);

		for (i = 0; i < n; i++) {

			int size = min_t(int, left, PAGE_SIZE - start);



			buf.page = pages[i];

			buf.offset = start;

			buf.len = size;

			ret = add_to_pipe(pipe, &buf);

			if (unlikely(ret < 0)) {

					failed = true;

				} else {

					iov_iter_advance(from, ret);

					total += ret;

				}

			} else {

				put_page(pages[n]);

				iov_iter_revert(from, left);

				// this one got dropped by add_to_pipe()

				while (++i < n)

					put_page(pages[i]);

				goto out;

			}

			copied -= size;

			total += ret;

			left -= size;

			start = 0;

		}

	}

out:

	return total ? total : ret;

}