diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/find_next_bit.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/lib/find_next_bit.c b/lib/find_next_bit.c index bda0d71a2514..78ccd73a8841 100644 --- a/lib/find_next_bit.c +++ b/lib/find_next_bit.c @@ -178,4 +178,47 @@ found_middle_swap: EXPORT_SYMBOL(generic_find_next_zero_le_bit); +unsigned long generic_find_next_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 << 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)) { + tmp = *(p++); + if (tmp) + goto found_middle_swap; + result += BITS_PER_LONG; + size -= BITS_PER_LONG; + } + if (!size) + return result; + tmp = ext2_swabp(p); +found_first: + tmp &= (~0UL >> (BITS_PER_LONG - size)); + if (tmp == 0UL) /* Are any bits set? */ + return result + size; /* Nope. */ +found_middle: + return result + __ffs(tmp); + +found_middle_swap: + return result + __ffs(ext2_swab(tmp)); +} +EXPORT_SYMBOL(generic_find_next_le_bit); #endif /* __BIG_ENDIAN */ |