diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/f2fs/segment.c | 46 |
1 files changed, 18 insertions, 28 deletions
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index f77b3258454a..efbf6b5f1dc3 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -86,6 +86,7 @@ static inline unsigned long __reverse_ffs(unsigned long word) /* * __find_rev_next(_zero)_bit is copied from lib/find_next_bit.c because * f2fs_set_bit makes MSB and LSB reversed in a byte. + * @size must be integral times of unsigned long. * Example: * MSB <--> LSB * f2fs_set_bit(0, bitmap) => 1000 0000 @@ -95,47 +96,36 @@ static unsigned long __find_rev_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset) { const unsigned long *p = addr + BIT_WORD(offset); - unsigned long result = offset & ~(BITS_PER_LONG - 1); + unsigned long result = size; unsigned long tmp; if (offset >= size) return size; - size -= result; + size -= (offset & ~(BITS_PER_LONG - 1)); offset %= BITS_PER_LONG; - if (!offset) - goto aligned; - tmp = __reverse_ulong((unsigned char *)p); - tmp &= ~0UL >> offset; - - if (size < BITS_PER_LONG) - goto found_first; - if (tmp) - goto found_middle; + while (1) { + if (*p == 0) + goto pass; - size -= BITS_PER_LONG; - result += BITS_PER_LONG; - p++; -aligned: - while (size & ~(BITS_PER_LONG-1)) { tmp = __reverse_ulong((unsigned char *)p); + + tmp &= ~0UL >> offset; + if (size < BITS_PER_LONG) + tmp &= (~0UL << (BITS_PER_LONG - size)); if (tmp) - goto found_middle; - result += BITS_PER_LONG; + goto found; +pass: + if (size <= BITS_PER_LONG) + break; size -= BITS_PER_LONG; + offset = 0; p++; } - if (!size) - return result; - - tmp = __reverse_ulong((unsigned char *)p); -found_first: - tmp &= (~0UL << (BITS_PER_LONG - size)); - if (!tmp) /* Are any bits set? */ - return result + size; /* Nope. */ -found_middle: - return result + __reverse_ffs(tmp); + return result; +found: + return result - size + __reverse_ffs(tmp); } static unsigned long __find_rev_next_zero_bit(const unsigned long *addr, |