diff options
| -rw-r--r-- | include/asm-generic/bitops/ext2-non-atomic.h | 18 | ||||
| -rw-r--r-- | include/asm-generic/bitops/le.h | 53 | ||||
| -rw-r--r-- | lib/find_next_bit.c | 73 |
3 files changed, 144 insertions, 0 deletions
diff --git a/include/asm-generic/bitops/ext2-non-atomic.h b/include/asm-generic/bitops/ext2-non-atomic.h new file mode 100644 index 00000000000..1697404afa0 --- /dev/null +++ b/include/asm-generic/bitops/ext2-non-atomic.h @@ -0,0 +1,18 @@ +#ifndef _ASM_GENERIC_BITOPS_EXT2_NON_ATOMIC_H_ +#define _ASM_GENERIC_BITOPS_EXT2_NON_ATOMIC_H_ + +#include <asm-generic/bitops/le.h> + +#define ext2_set_bit(nr,addr) \ + generic___test_and_set_le_bit((nr),(unsigned long *)(addr)) +#define ext2_clear_bit(nr,addr) \ + generic___test_and_clear_le_bit((nr),(unsigned long *)(addr)) + +#define ext2_test_bit(nr,addr) \ + generic_test_le_bit((nr),(unsigned long *)(addr)) +#define ext2_find_first_zero_bit(addr, size) \ + generic_find_first_zero_le_bit((unsigned long *)(addr), (size)) +#define ext2_find_next_zero_bit(addr, size, off) \ + generic_find_next_zero_le_bit((unsigned long *)(addr), (size), (off)) + +#endif /* _ASM_GENERIC_BITOPS_EXT2_NON_ATOMIC_H_ */ diff --git a/include/asm-generic/bitops/le.h b/include/asm-generic/bitops/le.h new file mode 100644 index 00000000000..b9c7e5d2d2a --- /dev/null +++ b/include/asm-generic/bitops/le.h @@ -0,0 +1,53 @@ +#ifndef _ASM_GENERIC_BITOPS_LE_H_ +#define _ASM_GENERIC_BITOPS_LE_H_ + +#include <asm/types.h> +#include <asm/byteorder.h> + +#define BITOP_WORD(nr) ((nr) / BITS_PER_LONG) +#define BITOP_LE_SWIZZLE ((BITS_PER_LONG-1) & ~0x7) + +#if defined(__LITTLE_ENDIAN) + +#define generic_test_le_bit(nr, addr) test_bit(nr, addr) +#define generic___set_le_bit(nr, addr) __set_bit(nr, addr) +#define generic___clear_le_bit(nr, addr) __clear_bit(nr, addr) + +#define generic_test_and_set_le_bit(nr, addr) test_and_set_bit(nr, addr) +#define generic_test_and_clear_le_bit(nr, addr) test_and_clear_bit(nr, addr) + +#define generic___test_and_set_le_bit(nr, addr) __test_and_set_bit(nr, addr) +#define generic___test_and_clear_le_bit(nr, addr) __test_and_clear_bit(nr, addr) + +#define generic_find_next_zero_le_bit(addr, size, offset) find_next_zero_bit(addr, size, offset) + +#elif defined(__BIG_ENDIAN) + +#define generic_test_le_bit(nr, addr) \ + test_bit((nr) ^ BITOP_LE_SWIZZLE, (addr)) +#define generic___set_le_bit(nr, addr) \ + __set_bit((nr) ^ BITOP_LE_SWIZZLE, (addr)) +#define generic___clear_le_bit(nr, addr) \ + __clear_bit((nr) ^ BITOP_LE_SWIZZLE, (addr)) + +#define generic_test_and_set_le_bit(nr, addr) \ + test_and_set_bit((nr) ^ BITOP_LE_SWIZZLE, (addr)) +#define generic_test_and_clear_le_bit(nr, addr) \ + test_and_clear_bit((nr) ^ BITOP_LE_SWIZZLE, (addr)) + +#define generic___test_and_set_le_bit(nr, addr) \ + __test_and_set_bit((nr) ^ BITOP_LE_SWIZZLE, (addr)) +#define generic___test_and_clear_le_bit(nr, addr) \ + __test_and_clear_bit((nr) ^ BITOP_LE_SWIZZLE, (addr)) + +extern unsigned long generic_find_next_zero_le_bit(const unsigned long *addr, + unsigned long size, unsigned long offset); + +#else +#error "Please fix <asm/byteorder.h>" +#endif + +#define generic_find_first_zero_le_bit(addr, size) \ + generic_find_next_zero_le_bit((addr), (size), 0) + +#endif /* _ASM_GENERIC_BITOPS_LE_H_ */ diff --git a/lib/find_next_bit.c b/lib/find_next_bit.c index 9c90853b447..bda0d71a251 100644 --- a/lib/find_next_bit.c +++ b/lib/find_next_bit.c @@ -12,6 +12,7 @@ #include <linux/bitops.h> #include <linux/module.h> #include <asm/types.h> +#include <asm/byteorder.h> #define BITOP_WORD(nr) ((nr) / BITS_PER_LONG) @@ -106,3 +107,75 @@ found_middle: } EXPORT_SYMBOL(find_next_zero_bit); + +#ifdef __BIG_ENDIAN + +/* include/linux/byteorder does not support "unsigned long" type */ +static inline unsigned long ext2_swabp(const unsigned long * x) +{ +#if BITS_PER_LONG == 64 + return (unsigned long) __swab64p((u64 *) x); +#elif BITS_PER_LONG == 32 + return (unsigned long) __swab32p((u32 *) x); +#else +#error BITS_PER_LONG not defined +#endif +} + +/* include/linux/byteorder doesn't support "unsigned long" type */ +static inline unsigned long ext2_swab(const unsigned long y) +{ +#if BITS_PER_LONG == 64 + return (unsigned long) __swab64((u64) y); +#elif BITS_PER_LONG == 32 + return (unsigned long) __swab32((u32) y); +#else +#error BITS_PER_LONG not defined +#endif +} + +unsigned long generic_find_next_zero_le_bit(const unsigned long *addr, unsigned + long size, unsigned long offset) +{ + const unsigned long *p = addr + BITOP_WORD(offset); + unsigned long result = offset & ~(BITS_PER_LONG - 1); + unsigned long tmp; + + if (offset >= size) + return size; + size -= result; + offset &= (BITS_PER_LONG - 1UL); + if (offset) { + tmp = ext2_swabp(p++); + tmp |= (~0UL >> (BITS_PER_LONG - offset)); + if (size < BITS_PER_LONG) + goto found_first; + if (~tmp) + goto found_middle; + size -= BITS_PER_LONG; + result += BITS_PER_LONG; + } + + while (size & ~(BITS_PER_LONG - 1)) { + if (~(tmp = *(p++))) + goto found_middle_swap; + result += BITS_PER_LONG; + size -= BITS_PER_LONG; + } + if (!size) + return result; + tmp = ext2_swabp(p); +found_first: + tmp |= ~0UL << size; + if (tmp == ~0UL) /* Are any bits zero? */ + return result + size; /* Nope. Skip ffz */ +found_middle: + return result + ffz(tmp); + +found_middle_swap: + return result + ffz(ext2_swab(tmp)); +} + +EXPORT_SYMBOL(generic_find_next_zero_le_bit); + +#endif /* __BIG_ENDIAN */ |