diff options
| -rw-r--r-- | include/linux/bitmap.h | 36 | ||||
| -rw-r--r-- | lib/bitmap.c | 24 |
2 files changed, 44 insertions, 16 deletions
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index e1c8d080c427..34e020c23644 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -45,6 +45,7 @@ * bitmap_set(dst, pos, nbits) Set specified bit area * bitmap_clear(dst, pos, nbits) Clear specified bit area * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area + * bitmap_find_next_zero_area_off(buf, len, pos, n, mask) as above * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src) @@ -114,11 +115,36 @@ extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits); extern void bitmap_set(unsigned long *map, unsigned int start, int len); extern void bitmap_clear(unsigned long *map, unsigned int start, int len); -extern unsigned long bitmap_find_next_zero_area(unsigned long *map, - unsigned long size, - unsigned long start, - unsigned int nr, - unsigned long align_mask); + +extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map, + unsigned long size, + unsigned long start, + unsigned int nr, + unsigned long align_mask, + unsigned long align_offset); + +/** + * bitmap_find_next_zero_area - find a contiguous aligned zero area + * @map: The address to base the search on + * @size: The bitmap size in bits + * @start: The bitnumber to start searching at + * @nr: The number of zeroed bits we're looking for + * @align_mask: Alignment mask for zero area + * + * The @align_mask should be one less than a power of 2; the effect is that + * the bit offset of all zero areas this function finds is multiples of that + * power of 2. A @align_mask of 0 means no alignment is required. + */ +static inline unsigned long +bitmap_find_next_zero_area(unsigned long *map, + unsigned long size, + unsigned long start, + unsigned int nr, + unsigned long align_mask) +{ + return bitmap_find_next_zero_area_off(map, size, start, nr, + align_mask, 0); +} extern int bitmap_scnprintf(char *buf, unsigned int len, const unsigned long *src, int nbits); diff --git a/lib/bitmap.c b/lib/bitmap.c index b499ab6ada29..969ae8fbc85b 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -326,30 +326,32 @@ void bitmap_clear(unsigned long *map, unsigned int start, int len) } EXPORT_SYMBOL(bitmap_clear); -/* - * bitmap_find_next_zero_area - find a contiguous aligned zero area +/** + * bitmap_find_next_zero_area_off - find a contiguous aligned zero area * @map: The address to base the search on * @size: The bitmap size in bits * @start: The bitnumber to start searching at * @nr: The number of zeroed bits we're looking for * @align_mask: Alignment mask for zero area + * @align_offset: Alignment offset for zero area. * * The @align_mask should be one less than a power of 2; the effect is that - * the bit offset of all zero areas this function finds is multiples of that - * power of 2. A @align_mask of 0 means no alignment is required. + * the bit offset of all zero areas this function finds plus @align_offset + * is multiple of that power of 2. */ -unsigned long bitmap_find_next_zero_area(unsigned long *map, - unsigned long size, - unsigned long start, - unsigned int nr, - unsigned long align_mask) +unsigned long bitmap_find_next_zero_area_off(unsigned long *map, + unsigned long size, + unsigned long start, + unsigned int nr, + unsigned long align_mask, + unsigned long align_offset) { unsigned long index, end, i; again: index = find_next_zero_bit(map, size, start); /* Align allocation */ - index = __ALIGN_MASK(index, align_mask); + index = __ALIGN_MASK(index + align_offset, align_mask) - align_offset; end = index + nr; if (end > size) @@ -361,7 +363,7 @@ again: } return index; } -EXPORT_SYMBOL(bitmap_find_next_zero_area); +EXPORT_SYMBOL(bitmap_find_next_zero_area_off); /* * Bitmap printing & parsing functions: first version by Nadia Yvette Chambers, |