[PATCH v2 05/22] m68k: introduce little-endian bitops

Akinobu Mita
2010-10-21T14:41:00Z

Introduce little-endian bit operations by renaming native ext2 bit
operations. The ext2 bit operations are kept as wrapper macros using
little-endian bit operations to maintain bisectability until the
conversions are finished.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
---
Change from v1: fix argument of test_and_{set,clear}_le_bit()

arch/m68k/include/asm/bitops_mm.h | 64 +++++++++++++++++++++++++-----------
1 files changed, 44 insertions(+), 20 deletions(-)

diff --git a/arch/m68k/include/asm/bitops_mm.h b/arch/m68k/include/asm/bitops_mm.h
index f1010ab..7f15f80 100644
--- a/arch/m68k/include/asm/bitops_mm.h
+++ b/arch/m68k/include/asm/bitops_mm.h
@@ -359,24 +359,28 @@ static inline int minix_test_bit(int nr, const void *vaddr)
return (p[nr >> 4] & (1U << (nr & 15))) != 0;
}

-/* Bitmap functions for the ext2 filesystem. */
-
-#define ext2_set_bit(nr, addr) __test_and_set_bit((nr) ^ 24, (unsigned long *)(addr))
-#define ext2_set_bit_atomic(lock, nr, addr) test_and_set_bit((nr) ^ 24, (unsigned long *)(addr))
-#define ext2_clear_bit(nr, addr) __test_and_clear_bit((nr) ^ 24, (unsigned long *)(addr))
-#define ext2_clear_bit_atomic(lock, nr, addr) test_and_clear_bit((nr) ^ 24, (unsigned long *)(addr))
-#define ext2_find_next_zero_bit(addr, size, offset) \
- find_next_zero_le_bit((unsigned long *)addr, size, offset)
-#define ext2_find_next_bit(addr, size, offset) \
- find_next_le_bit((unsigned long *)addr, size, offset)
-
-static inline int ext2_test_bit(int nr, const void *vaddr)
+/* Bitmap functions for little endian. */
+
+#define __set_le_bit(nr, addr) \
+ __set_bit((nr) ^ 24, (addr))
+#define __clear_le_bit(nr, addr) \
+ __clear_bit((nr) ^ 24, (addr))
+#define __test_and_set_le_bit(nr, addr) \
+ __test_and_set_bit((nr) ^ 24, (addr))
+#define test_and_set_le_bit(nr, addr) \
+ test_and_set_bit((nr) ^ 24, (addr))
+#define __test_and_clear_le_bit(nr, addr) \
+ __test_and_clear_bit((nr) ^ 24, (addr))
+#define test_and_clear_le_bit(nr, addr) \
+ test_and_clear_bit((nr) ^ 24, (addr))
+
+static inline int test_le_bit(int nr, const void *vaddr)
{
const unsigned char *p = vaddr;
return (p[nr >> 3] & (1U << (nr & 7))) != 0;
}

-static inline int ext2_find_first_zero_bit(const void *vaddr, unsigned size)
+static inline int find_first_zero_le_bit(const void *vaddr, unsigned size)
{
const unsigned long *p = vaddr, *addr = vaddr;
int res;
@@ -393,7 +397,7 @@ static inline int ext2_find_first_zero_bit(const void *vaddr, unsigned size)

--p;
for (res = 0; res < 32; res++)
- if (!ext2_test_bit (res, p))
+ if (!test_le_bit(res, p))
break;
return (p - addr) * 32 + res;
}
@@ -410,16 +414,16 @@ static inline unsigned long find_next_zero_le_bit(const unsigned long *addr,
if (bit) {
/* Look for zero in first longword */
for (res = bit; res < 32; res++)
- if (!ext2_test_bit (res, p))
+ if (!test_le_bit(res, p))
return (p - addr) * 32 + res;
p++;
}
/* No zero yet, search remaining full bytes for a zero */
- res = ext2_find_first_zero_bit (p, size - 32 * (p - addr));
+ res = find_first_zero_le_bit(p, size - 32 * (p - addr));
return (p - addr) * 32 + res;
}

-static inline int ext2_find_first_bit(const void *vaddr, unsigned size)
+static inline int find_first_le_bit(const void *vaddr, unsigned size)
{
const unsigned long *p = vaddr, *addr = vaddr;
int res;
@@ -435,7 +439,7 @@ static inline int ext2_find_first_bit(const void *vaddr, unsigned size)

--p;
for (res = 0; res < 32; res++)
- if (ext2_test_bit(res, p))
+ if (test_le_bit(res, p))
break;
return (p - addr) * 32 + res;
}
@@ -452,15 +456,35 @@ static inline unsigned long find_next_le_bit(const unsigned long *addr,
if (bit) {
/* Look for one in first longword */
for (res = bit; res < 32; res++)
- if (ext2_test_bit(res, p))
+ if (test_le_bit(res, p))
return (p - addr) * 32 + res;
p++;
}
/* No set bit yet, search remaining full bytes for a set bit */
- res = ext2_find_first_bit(p, size - 32 * (p - addr));
+ res = find_first_le_bit(p, size - 32 * (p - addr));
return (p - addr) * 32 + res;
}

+/* Bitmap functions for the ext2 filesystem. */
+
+#define ext2_set_bit(nr, addr) \
+ __test_and_set_le_bit(nr, (unsigned long *)(addr))
+#define ext2_set_bit_atomic(lock, nr, addr) \
+ test_and_set_le_bit(nr, (unsigned long *)(addr))
+#define ext2_clear_bit(nr, addr) \
+ __test_and_clear_le_bit(nr, (unsigned long *)(addr))
+#define ext2_clear_bit_atomic(lock, nr, addr) \
+ test_and_clear_le_bit(nr, (unsigned long *)(addr))
+#define ext2_find_next_zero_bit(addr, size, offset) \
+ find_next_zero_le_bit((unsigned long *)(addr), size, offset)
+#define ext2_find_next_bit(addr, size, offset) \
+ find_next_le_bit((unsigned long *)(addr), size, offset)
+#define ext2_test_bit(nr, vaddr) test_le_bit(nr, vaddr)
+#define ext2_find_first_zero_bit(vaddr, size) \
+ find_first_zero_le_bit((unsigned long *)(vaddr), size)
+#define ext2_find_first_bit(vaddr, size) \
+ find_first_le_bit((unsigned long *)(vaddr), size)
+
#endif /* __KERNEL__ */

#endif /* _M68K_BITOPS_H */
--
1.7.1.231.gd0b16