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
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+24 −23
Original line number Original line Diff line number Diff line
@@ -1158,39 +1158,40 @@ static int iter_to_pipe(struct iov_iter *from,
	};
	};
	size_t total = 0;
	size_t total = 0;
	int ret = 0;
	int ret = 0;
	bool failed = false;


	while (iov_iter_count(from) && !failed) {
	while (iov_iter_count(from)) {
		struct page *pages[16];
		struct page *pages[16];
		ssize_t copied;
		ssize_t left;
		size_t start;
		size_t start;
		int n;
		int i, n;


		copied = iov_iter_get_pages(from, pages, ~0UL, 16, &start);
		left = iov_iter_get_pages2(from, pages, ~0UL, 16, &start);
		if (copied <= 0) {
		if (left <= 0) {
			ret = copied;
			ret = left;
			break;
			break;
		}
		}


		for (n = 0; copied; n++, start = 0) {
		n = DIV_ROUND_UP(left + start, PAGE_SIZE);
			int size = min_t(int, copied, PAGE_SIZE - start);
		for (i = 0; i < n; i++) {
			if (!failed) {
			int size = min_t(int, left, PAGE_SIZE - start);
				buf.page = pages[n];

			buf.page = pages[i];
			buf.offset = start;
			buf.offset = start;
			buf.len = size;
			buf.len = size;
			ret = add_to_pipe(pipe, &buf);
			ret = add_to_pipe(pipe, &buf);
			if (unlikely(ret < 0)) {
			if (unlikely(ret < 0)) {
					failed = true;
				iov_iter_revert(from, left);
				} else {
				// this one got dropped by add_to_pipe()
					iov_iter_advance(from, ret);
				while (++i < n)
					total += ret;
					put_page(pages[i]);
				}
				goto out;
			} else {
				put_page(pages[n]);
			}
			}
			copied -= size;
			total += ret;
			left -= size;
			start = 0;
		}
		}
	}
	}
out:
	return total ? total : ret;
	return total ? total : ret;
}
}