x86: unify pgd ctor/dtor

All pagetables need fundamentally the same setup and destruction, so
just use the same code for everything.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 16 insertions, 0 deletions

diff --git a/include/asm-x86/pgtable.h b/include/asm-x86/pgtable.h
index e61075e70a54..b8a08bd7bd48 100644
--- a/include/asm-x86/pgtable.h
+++ b/include/asm-x86/pgtable.h
@@ -438,6 +438,22 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm,
         pte_update(mm, addr, ptep);
 }
 
+/*
+ * clone_pgd_range(pgd_t *dst, pgd_t *src, int count);
+ *
+ *  dst - pointer to pgd range anwhere on a pgd page
+ *  src - ""
+ *  count - the number of pgds to copy.
+ *
+ * dst and src can be on the same page, but the range must not overlap,
+ * and must not cross a page boundary.
+ */
+static inline void clone_pgd_range(pgd_t *dst, pgd_t *src, int count)
+{
+       memcpy(dst, src, count * sizeof(pgd_t));
+}
+
+
 #include <asm-generic/pgtable.h>
 #endif  /* __ASSEMBLY__ */