From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: john.hubbard@gmail.com To: Matthew Wilcox , Michal Hocko , Christopher Lameter , Jason Gunthorpe , Dan Williams , Jan Kara , Al Viro Cc: linux-mm@kvack.org, LKML , linux-rdma , linux-fsdevel@vger.kernel.org, John Hubbard Subject: [PATCH 1/2] mm: introduce put_user_page(), placeholder version Date: Mon, 9 Jul 2018 01:05:53 -0700 Message-Id: <20180709080554.21931-2-jhubbard@nvidia.com> In-Reply-To: <20180709080554.21931-1-jhubbard@nvidia.com> References: <20180709080554.21931-1-jhubbard@nvidia.com> Sender: owner-linux-mm@kvack.org List-ID: From: John Hubbard Introduces put_user_page(), which simply calls put_page(). This provides a safe way to update all get_user_pages*() callers, so that they call put_user_page(), instead of put_page(). Also adds release_user_pages(), a drop-in replacement for release_pages(). This is intended to be easily grep-able, for later performance improvements, since release_user_pages is not batched like release_pages is, and is significantly slower. Subsequent patches will add functionality to put_user_page(). Signed-off-by: John Hubbard --- include/linux/mm.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index a0fbb9ffe380..db4a211aad79 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -923,6 +923,20 @@ static inline void put_page(struct page *page) __put_page(page); } +/* Placeholder version, until all get_user_pages*() callers are updated. */ +static inline void put_user_page(struct page *page) +{ + put_page(page); +} + +/* A drop-in replacement for release_pages(): */ +static inline void release_user_pages(struct page **pages, + unsigned long npages) +{ + while (npages) + put_user_page(pages[--npages]); +} + #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) #define SECTION_IN_PAGE_FLAGS #endif -- 2.18.0