[PATCH v4 07/16] x86: add pmd_[dirty|mkclean] for THP

Minchan Kim
2015-11-20T08:06:52Z

MADV_FREE needs pmd_dirty and pmd_mkclean for detecting recent overwrite
of the contents since MADV_FREE syscall is called for THP page.

This patch adds pmd_dirty and pmd_mkclean for THP page MADV_FREE
support.

Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
arch/x86/include/asm/pgtable.h | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 867da5bbb4a3..b964d54300e1 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -267,6 +267,11 @@ static inline pmd_t pmd_mkold(pmd_t pmd)
return pmd_clear_flags(pmd, _PAGE_ACCESSED);
}

+static inline pmd_t pmd_mkclean(pmd_t pmd)
+{
+ return pmd_clear_flags(pmd, _PAGE_DIRTY);
+}
+
static inline pmd_t pmd_wrprotect(pmd_t pmd)
{
return pmd_clear_flags(pmd, _PAGE_RW);
--
1.9.1