On Thu, Aug 28, 2025 at 12:01:23AM +0200, David Hildenbrand wrote:
Within a folio/compound page, nth_page() is no longer required. Given that we call folio_test_partial_kmap()+kmap_local_page(), the code would already be problematic if the pages would span multiple folios.
So let's just assume that all src pages belong to a single folio/compound page and can be iterated ordinarily. The dst page is currently always a single page, so we're not actually iterating anything.
Reviewed-by: Pavel Begunkov asml.silence@gmail.com Cc: Jens Axboe axboe@kernel.dk Cc: Pavel Begunkov asml.silence@gmail.com Signed-off-by: David Hildenbrand david@redhat.com
On basis of src pages being within the same folio, LGTM, so:
Reviewed-by: Lorenzo Stoakes lorenzo.stoakes@oracle.com
io_uring/zcrx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c index e5ff49f3425e0..18c12f4b56b6c 100644 --- a/io_uring/zcrx.c +++ b/io_uring/zcrx.c @@ -975,9 +975,9 @@ static ssize_t io_copy_page(struct io_copy_cache *cc, struct page *src_page,
if (folio_test_partial_kmap(page_folio(dst_page)) || folio_test_partial_kmap(page_folio(src_page))) {
dst_page = nth_page(dst_page, dst_offset / PAGE_SIZE);
dst_page += dst_offset / PAGE_SIZE; dst_offset = offset_in_page(dst_offset);
src_page = nth_page(src_page, src_offset / PAGE_SIZE);
src_page += src_offset / PAGE_SIZE; src_offset = offset_in_page(src_offset); n = min(PAGE_SIZE - src_offset, PAGE_SIZE - dst_offset); n = min(n, len);-- 2.50.1