This patch fixes below build error by adding the missing asm/memory.h,
which is needed for arch_is_coherent().

$ make pxa3xx_defconfig; make
  CC      init/do_mounts_rd.o
In file included from include/linux/list_bl.h:5,
                 from include/linux/rculist_bl.h:7,
                 from include/linux/dcache.h:7,
                 from include/linux/fs.h:381,
                 from init/do_mounts_rd.c:3:
include/linux/bit_spinlock.h: In function 'bit_spin_unlock':
include/linux/bit_spinlock.h:61: error: implicit declaration of function 'arch_is_coherent'
make[1]: *** [init/do_mounts_rd.o] Error 1
make: *** [init] Error 2

Signed-off-by: Axel Lin <redacted>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
---
It was posted on https://lkml.org/lkml/2010/12/17/9 .
I still have the build error for today's linux-next tree.
CC Eric Miao, maybe he will take this patch.

Axel

 arch/arm/include/asm/system.h |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h
index ec4327a..3222ab8 100644
--- a/arch/arm/include/asm/system.h
+++ b/arch/arm/include/asm/system.h

@@ -155,6 +155,7 @@ extern unsigned int user_debug;
 #define rmb()		dmb()
 #define wmb()		mb()
 #else
+#include <asm/memory.h>
 #define mb()	do { if (arch_is_coherent()) dmb(); else barrier(); } while (0)
 #define rmb()	do { if (arch_is_coherent()) dmb(); else barrier(); } while (0)
 #define wmb()	do { if (arch_is_coherent()) dmb(); else barrier(); } while (0)

-- 
1.7.2