mm: add VM_BUG_ON_PAGE() to page_mapcount()
authorWang, Yalin <Yalin.Wang@sonymobile.com>
Wed, 11 Feb 2015 23:24:48 +0000 (15:24 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 12 Feb 2015 01:06:00 +0000 (17:06 -0800)
commit1d148e218a0d0566b1c06f2f45f1436d53b049b2
tree39e416568334e656764c3a5eab0b5939f6121779
parente4b294c2d8f73af4cd41ff30638ad0e4769dc56a
mm: add VM_BUG_ON_PAGE() to page_mapcount()

Add VM_BUG_ON_PAGE() for slab pages.  _mapcount is an union with slab
struct in struct page, so we must avoid accessing _mapcount if this page
is a slab page.  Also remove the unneeded bracket.

Signed-off-by: Yalin Wang <yalin.wang@sonymobile.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/mm.h