arch/tile: allow building Linux with transparent huge pages enabled
The change adds some infrastructure for managing tile pmd's more generally,
using pte_pmd() and pmd_pte() methods to translate pmd values to and
from ptes, since on TILEPro a pmd is really just a nested structure
holding a pgd (aka pte). Several existing pmd methods are moved into
this framework, and a whole raft of additional pmd accessors are defined
that are used by the transparent hugepage framework.
The tile PTE now has a "client2" bit. The bit is used to indicate a
transparent huge page is in the process of being split into subpages.
This change also fixes a generic bug where the return value of the
generic pmdp_splitting_flush() was incorrect.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 125c54e..e2768f1 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -158,9 +158,8 @@
#endif
#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
-extern pmd_t pmdp_splitting_flush(struct vm_area_struct *vma,
- unsigned long address,
- pmd_t *pmdp);
+extern void pmdp_splitting_flush(struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmdp);
#endif
#ifndef __HAVE_ARCH_PTE_SAME