[RFC PATCH 8/9] powerpc: mm: Support setting _PAGE_NUMA bit on pmd entry which are pointer to PTE page

[Aneesh Kumar K.V]

From: "Aneesh Kumar K.V" <aneesh.kumar at linux.vnet.ibm.com>

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/pgtable-ppc64.h | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/pgtable-ppc64.h b/arch/powerpc/include/asm/pgtable-ppc64.h
index 46db094..f828944 100644
--- a/arch/powerpc/include/asm/pgtable-ppc64.h
+++ b/arch/powerpc/include/asm/pgtable-ppc64.h
@@ -150,8 +150,22 @@
 
 #define pmd_set(pmdp, pmdval) 	(pmd_val(*(pmdp)) = (pmdval))
 #define pmd_none(pmd)		(!pmd_val(pmd))
-#define	pmd_bad(pmd)		(!is_kernel_addr(pmd_val(pmd)) \
-				 || (pmd_val(pmd) & PMD_BAD_BITS))
+
+static inline int pmd_bad(pmd_t pmd)
+{
+#ifdef CONFIG_NUMA_BALANCING
+	/*
+	 * For numa balancing we can have this set
+	 */
+	if (pmd_val(pmd) & _PAGE_NUMA)
+		return 0;
+#endif
+	if (!is_kernel_addr(pmd_val(pmd)) ||
+	    (pmd_val(pmd) & PMD_BAD_BITS))
+		return 1;
+	return 0;
+}
+
 #define	pmd_present(pmd)	(pmd_val(pmd) != 0)
 #define	pmd_clear(pmdp)		(pmd_val(*(pmdp)) = 0)
 #define pmd_page_vaddr(pmd)	(pmd_val(pmd) & ~PMD_MASKED_BITS)
-- 
1.8.3.2