From c31ae4bb4a9fa4606a74c0a4fb61b74f804e861e Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 13 May 2009 22:56:25 +0000 Subject: asm-generic: introduce asm/bitsperlong.h This provides a reliable way for asm-generic/types.h and other files to find out if it is running on a 32 or 64 bit platform. We cannot use CONFIG_64BIT for this in headers that are included from user space because CONFIG symbols are not available there. We also cannot do it inside of asm/types.h because some headers need the word size but cannot include types.h. The solution is to introduce a new header that defines both __BITS_PER_LONG for user space and BITS_PER_LONG for usage in the kernel. The asm-generic version falls back to 32 bit unless the architecture overrides it, which I did for all 64 bit platforms. Signed-off-by: Remis Lima Baima Signed-off-by: Arnd Bergmann --- include/asm-generic/bitsperlong.h | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 include/asm-generic/bitsperlong.h (limited to 'include/asm-generic/bitsperlong.h') diff --git a/include/asm-generic/bitsperlong.h b/include/asm-generic/bitsperlong.h new file mode 100644 index 000000000000..4ae54e07de83 --- /dev/null +++ b/include/asm-generic/bitsperlong.h @@ -0,0 +1,32 @@ +#ifndef __ASM_GENERIC_BITS_PER_LONG +#define __ASM_GENERIC_BITS_PER_LONG + +/* + * There seems to be no way of detecting this automatically from user + * space, so 64 bit architectures should override this in their + * bitsperlong.h. In particular, an architecture that supports + * both 32 and 64 bit user space must not rely on CONFIG_64BIT + * to decide it, but rather check a compiler provided macro. + */ +#ifndef __BITS_PER_LONG +#define __BITS_PER_LONG 32 +#endif + +#ifdef __KERNEL__ + +#ifdef CONFIG_64BIT +#define BITS_PER_LONG 64 +#else +#define BITS_PER_LONG 32 +#endif /* CONFIG_64BIT */ + +/* + * FIXME: The check currently breaks x86-64 build, so it's + * temporarily disabled. Please fix x86-64 and reenable + */ +#if 0 && BITS_PER_LONG != __BITS_PER_LONG +#error Inconsistent word size. Check asm/bitsperlong.h +#endif + +#endif /* __KERNEL__ */ +#endif /* __ASM_GENERIC_BITS_PER_LONG */ -- cgit v1.2.3