Commit 746de1f8 authored by Al Viro's avatar Al Viro
Browse files

pipe_get_pages(): switch to append_pipe() 



now that we are advancing the iterator, there's no need to
treat the first page separately - just call append_pipe()
in a loop.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent eba2d3d7

lib/iov_iter.c

+6 −29
Original line number Diff line number Diff line
@@ -1304,10 +1304,9 @@ static ssize_t pipe_get_pages(struct iov_iter *i, 
		   struct page ***pages, size_t maxsize, unsigned maxpages,

		   size_t *start)

{

	struct pipe_inode_info *pipe = i->pipe;

	unsigned int npages, off, count;

	unsigned int npages, count, off, chunk;

	struct page **p;

	ssize_t left;

	size_t left;



	if (!sanity(i))

		return -EFAULT;
@@ -1319,38 +1318,16 @@ static ssize_t pipe_get_pages(struct iov_iter *i, 
	if (!count)

		return -ENOMEM;

	p = *pages;

	left = maxsize;

	npages = 0;

	if (off) {

		struct pipe_buffer *buf = pipe_buf(pipe, pipe->head - 1);



		get_page(*p++ = buf->page);

		left -= PAGE_SIZE - off;

		if (left <= 0) {

			buf->len += maxsize;

			iov_iter_advance(i, maxsize);

			return maxsize;

		}

		buf->len = PAGE_SIZE;

		npages = 1;

	}

	for ( ; npages < count; npages++) {

		struct page *page;

		unsigned int size = min_t(ssize_t, left, PAGE_SIZE);



		if (pipe_full(pipe->head, pipe->tail, pipe->max_usage))

			break;

		page = push_anon(pipe, size);

	for (npages = 0, left = maxsize ; npages < count; npages++, left -= chunk) {

		struct page *page = append_pipe(i, left, &off);

		if (!page)

			break;

		chunk = min_t(size_t, left, PAGE_SIZE - off);

		get_page(*p++ = page);

		left -= size;

	}

	if (!npages)

		return -EFAULT;

	maxsize -= left;

	iov_iter_advance(i, maxsize);

	return maxsize;

	return maxsize - left;

}



static ssize_t iter_xarray_populate_pages(struct page **pages, struct xarray *xa,