From 68fe506f3731ecf7881de9512cc5f4c14fd13f3a Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 17 Jun 2022 13:48:03 -0400 Subject: [PATCH] unify xarray_get_pages() and xarray_get_pages_alloc() same as for pipes Reviewed-by: Jeff Layton Signed-off-by: Al Viro --- lib/iov_iter.c | 49 ++++++++++--------------------------------------- 1 file changed, 10 insertions(+), 39 deletions(-) diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 916c628..6904a1c 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -1373,7 +1373,7 @@ static ssize_t iter_xarray_populate_pages(struct page **pages, struct xarray *xa } static ssize_t iter_xarray_get_pages(struct iov_iter *i, - struct page **pages, size_t maxsize, + struct page ***pages, size_t maxsize, unsigned maxpages, size_t *_start_offset) { unsigned nr, offset; @@ -1398,7 +1398,13 @@ static ssize_t iter_xarray_get_pages(struct iov_iter *i, if (count > maxpages) count = maxpages; - nr = iter_xarray_populate_pages(pages, i->xarray, index, count); + if (!*pages) { + *pages = get_pages_array(count); + if (!*pages) + return -ENOMEM; + } + + nr = iter_xarray_populate_pages(*pages, i->xarray, index, count); if (nr == 0) return 0; @@ -1490,46 +1496,11 @@ ssize_t iov_iter_get_pages(struct iov_iter *i, if (iov_iter_is_pipe(i)) return pipe_get_pages(i, &pages, maxsize, maxpages, start); if (iov_iter_is_xarray(i)) - return iter_xarray_get_pages(i, pages, maxsize, maxpages, start); + return iter_xarray_get_pages(i, &pages, maxsize, maxpages, start); return -EFAULT; } EXPORT_SYMBOL(iov_iter_get_pages); -static ssize_t iter_xarray_get_pages_alloc(struct iov_iter *i, - struct page ***pages, size_t maxsize, - size_t *_start_offset) -{ - struct page **p; - unsigned nr, offset; - pgoff_t index, count; - size_t size = maxsize; - loff_t pos; - - pos = i->xarray_start + i->iov_offset; - index = pos >> PAGE_SHIFT; - offset = pos & ~PAGE_MASK; - *_start_offset = offset; - - count = 1; - if (size > PAGE_SIZE - offset) { - size -= PAGE_SIZE - offset; - count += size >> PAGE_SHIFT; - size &= ~PAGE_MASK; - if (size) - count++; - } - - *pages = p = get_pages_array(count); - if (!p) - return -ENOMEM; - - nr = iter_xarray_populate_pages(p, i->xarray, index, count); - if (nr == 0) - return 0; - - return min_t(size_t, nr * PAGE_SIZE - offset, maxsize); -} - static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages, size_t maxsize, size_t *start) @@ -1580,7 +1551,7 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i, if (iov_iter_is_pipe(i)) return pipe_get_pages(i, pages, maxsize, ~0U, start); if (iov_iter_is_xarray(i)) - return iter_xarray_get_pages_alloc(i, pages, maxsize, start); + return iter_xarray_get_pages(i, pages, maxsize, ~0U, start); return -EFAULT; } -- 2.7.4