include/linux/mm.h: add PAGE_ALIGNED() helper

To test whether an address is aligned to PAGE_SIZE.

Cc: HATAYAMA Daisuke <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>,
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 66d881f1d57665b5791d3a5a357c8cbff3d4c9a0..949bd70358954a4435daa7a033c57b3c58398f06 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -52,6 +52,9 @@ extern unsigned long sysctl_admin_reserve_kbytes;
 /* to align the pointer to the (next) page boundary */
 #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
 
+/* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
+#define PAGE_ALIGNED(addr)     IS_ALIGNED((unsigned long)addr, PAGE_SIZE)
+
 /*
  * Linux kernel virtual memory manager primitives.
  * The idea being to have a "virtual" mm in the same way