asm-generic: add another generic ext2 atomic bitops

The majority of architectures implement ext2 atomic bitops as
test_and_{set,clear}_bit() without spinlock.

This adds this type of generic implementation in ext2-atomic-setbit.h and
use it wherever possible.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Suggested-by: Andreas Dilger <adilger@dilger.ca>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/asm-generic/bitops/ext2-atomic.h b/include/asm-generic/bitops/ext2-atomic.h
index ecf1c9d..87f0f10 100644
--- a/include/asm-generic/bitops/ext2-atomic.h
+++ b/include/asm-generic/bitops/ext2-atomic.h
@@ -1,6 +1,10 @@
 #ifndef _ASM_GENERIC_BITOPS_EXT2_ATOMIC_H_
 #define _ASM_GENERIC_BITOPS_EXT2_ATOMIC_H_
 
+/*
+ * Spinlock based version of ext2 atomic bitops
+ */
+
 #define ext2_set_bit_atomic(lock, nr, addr)		\
 	({						\
 		int ret;				\