path: root/arch/mips/include/asm/pgtable.h
diff options
authorHugh Dickins <hugh.dickins@tiscali.co.uk>2009-09-21 17:03:34 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-22 07:17:41 -0700
commit62eede62dafb4a6633eae7ffbeb34c60dba5e7b1 (patch)
treee55a0ca4ad0c55ad162443146268cfb4c473750f /arch/mips/include/asm/pgtable.h
parent3ae77f43b1118a76ea37952d444319c15e002c03 (diff)
Reinstate anonymous use of ZERO_PAGE to all architectures, not just to those which __HAVE_ARCH_PTE_SPECIAL: as suggested by Nick Piggin. Contrary to how I'd imagined it, there's nothing ugly about this, just a zero_pfn test built into one or another block of vm_normal_page(). But the MIPS ZERO_PAGE-of-many-colours case demands is_zero_pfn() and my_zero_pfn() inlines. Reinstate its mremap move_pte() shuffling of ZERO_PAGEs we did from 2.6.17 to 2.6.19? Not unless someone shouts for that: it would have to take vm_flags to weed out some cases. Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: Rik van Riel <riel@redhat.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/mips/include/asm/pgtable.h')
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 1a9f9b257551..d6eb6134abec 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -76,6 +76,16 @@ extern unsigned long zero_page_mask;
#define ZERO_PAGE(vaddr) \
(virt_to_page((void *)(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))))
+#define is_zero_pfn is_zero_pfn
+static inline int is_zero_pfn(unsigned long pfn)
+ extern unsigned long zero_pfn;
+ unsigned long offset_from_zero_pfn = pfn - zero_pfn;
+ return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT);
+#define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr))
extern void paging_init(void);