hugetlb: introduce pud_huge

Straight forward extensions for huge pages located in the PUD instead of
PMDs.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 24 insertions, 1 deletions

diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 52476fde8996..a4789e87a315 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -189,6 +189,11 @@ int pmd_huge(pmd_t pmd)
         return 0;
 }
 
+int pud_huge(pud_t pud)
+{
+        return 0;
+}
+
 struct page *
 follow_huge_pmd(struct mm_struct *mm, unsigned long address,
                 pmd_t *pmd, int write)
@@ -209,6 +214,11 @@ int pmd_huge(pmd_t pmd)
         return !!(pmd_val(pmd) & _PAGE_PSE);
 }
 
+int pud_huge(pud_t pud)
+{
+        return 0;
+}
+
 struct page *
 follow_huge_pmd(struct mm_struct *mm, unsigned long address,
                 pmd_t *pmd, int write)
@@ -217,9 +227,22 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
 
         page = pte_page(*(pte_t *)pmd);
         if (page)
-                page += ((address & ~HPAGE_MASK) >> PAGE_SHIFT);
+                page += ((address & ~PMD_MASK) >> PAGE_SHIFT);
         return page;
 }
+
+struct page *
+follow_huge_pud(struct mm_struct *mm, unsigned long address,
+                pud_t *pud, int write)
+{
+        struct page *page;
+
+        page = pte_page(*(pte_t *)pud);
+        if (page)
+                page += ((address & ~PUD_MASK) >> PAGE_SHIFT);
+        return page;
+}
+
 #endif
 
 /* x86_64 also uses this file */