[PATCH 1/2] mm: introduce put_user_page(), placeholder version

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: John Hubbard <jhubbard@xxxxxxxxxx>

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 <jhubbard@xxxxxxxxxx>
---
 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




[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [Samba]     [Device Mapper]     [CEPH Development]

  Powered by Linux