thp: add x86 32bit support

Add support for transparent hugepages to x86 32bit.

Share the same VM_ bitflag for VM_MAPPED_COPY.  mm/nommu.c will never
support transparent hugepages.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 3 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7ab7d2b60041..9c2695beab86 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -102,7 +102,11 @@ extern unsigned int kobjsize(const void *objp);
 #define VM_NORESERVE    0x00200000      /* should the VM suppress accounting */
 #define VM_HUGETLB      0x00400000      /* Huge TLB Page VM */
 #define VM_NONLINEAR    0x00800000      /* Is non-linear (remap_file_pages) */
+#ifndef CONFIG_TRANSPARENT_HUGEPAGE
 #define VM_MAPPED_COPY  0x01000000      /* T if mapped copy of data (nommu mmap) */
+#else
+#define VM_HUGEPAGE     0x01000000      /* MADV_HUGEPAGE marked this vma */
+#endif
 #define VM_INSERTPAGE   0x02000000      /* The vma has had "vm_insert_page()" done on it */
 #define VM_ALWAYSDUMP   0x04000000      /* Always include in core dumps */
 
@@ -111,9 +115,6 @@ extern unsigned int kobjsize(const void *objp);
 #define VM_SAO          0x20000000      /* Strong Access Ordering (powerpc) */
 #define VM_PFN_AT_MMAP  0x40000000      /* PFNMAP vma that is fully mapped at mmap time */
 #define VM_MERGEABLE    0x80000000      /* KSM may merge identical pages */
-#if BITS_PER_LONG > 32
-#define VM_HUGEPAGE     0x100000000UL   /* MADV_HUGEPAGE marked this vma */
-#endif
 
 /* Bits set in the VMA until the stack is in its final location */
 #define VM_STACK_INCOMPLETE_SETUP       (VM_RAND_READ | VM_SEQ_READ)