mm: fix atomic_t overflow in vm

The atomic_t type is 32bit but a 64bit system can have more than 2^32
pages of virtual address space available.  Without this we overflow on
ludicrously large mappings

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mman.h b/include/linux/mman.h
index 87920a0..dab8892 100644
--- a/include/linux/mman.h
+++ b/include/linux/mman.h
@@ -17,14 +17,14 @@
 
 extern int sysctl_overcommit_memory;
 extern int sysctl_overcommit_ratio;
-extern atomic_t vm_committed_space;
+extern atomic_long_t vm_committed_space;
 
 #ifdef CONFIG_SMP
 extern void vm_acct_memory(long pages);
 #else
 static inline void vm_acct_memory(long pages)
 {
-	atomic_add(pages, &vm_committed_space);
+	atomic_long_add(pages, &vm_committed_space);
 }
 #endif