[PATCH] bitops: generic ext2_{set,clear}_bit_atomic()

This patch introduces the C-language equivalents of the functions below:

int ext2_set_bit_atomic(int nr, volatile unsigned long *addr);
int ext2_clear_bit_atomic(int nr, volatile unsigned long *addr);

In include/asm-generic/bitops/ext2-atomic.h

This code largely copied from: include/asm-sparc/bitops.h

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/include/asm-generic/bitops/ext2-atomic.h b/include/asm-generic/bitops/ext2-atomic.h
new file mode 100644 (file)
index 0000000..ab1c875
--- /dev/null
+++ b/include/asm-generic/bitops/ext2-atomic.h
@@ -0,0 +1,22 @@
+#ifndef _ASM_GENERIC_BITOPS_EXT2_ATOMIC_H_
+#define _ASM_GENERIC_BITOPS_EXT2_ATOMIC_H_
+
+#define ext2_set_bit_atomic(lock, nr, addr)            \
+       ({                                              \
+               int ret;                                \
+               spin_lock(lock);                        \
+               ret = ext2_set_bit((nr), (unsigned long *)(addr)); \
+               spin_unlock(lock);                      \
+               ret;                                    \
+       })
+
+#define ext2_clear_bit_atomic(lock, nr, addr)          \
+       ({                                              \
+               int ret;                                \
+               spin_lock(lock);                        \
+               ret = ext2_clear_bit((nr), (unsigned long *)(addr)); \
+               spin_unlock(lock);                      \
+               ret;                                    \
+       })
+
+#endif /* _ASM_GENERIC_BITOPS_EXT2_ATOMIC_H_ */