From 746de1f86fcd33464acac047f111eea877f2f7a0 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 14 Jun 2022 16:38:53 -0400 Subject: [PATCH] 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: Al Viro --- lib/iov_iter.c | 35 ++++++----------------------------- 1 file changed, 6 insertions(+), 29 deletions(-) diff --git a/lib/iov_iter.c b/lib/iov_iter.c index c48c836..415d51b 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -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, -- 2.7.4