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Diffstat (limited to 'include/linux/bitmap.h')
| -rw-r--r-- | include/linux/bitmap.h | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h new file mode 100644 index 000000000..ea17cca9e --- /dev/null +++ b/include/linux/bitmap.h @@ -0,0 +1,331 @@ +#ifndef __LINUX_BITMAP_H +#define __LINUX_BITMAP_H + +#ifndef __ASSEMBLY__ + +#include <linux/types.h> +#include <linux/bitops.h> +#include <linux/string.h> +#include <linux/kernel.h> + +/* + * bitmaps provide bit arrays that consume one or more unsigned + * longs. The bitmap interface and available operations are listed + * here, in bitmap.h + * + * Function implementations generic to all architectures are in + * lib/bitmap.c. Functions implementations that are architecture + * specific are in various include/asm-<arch>/bitops.h headers + * and other arch/<arch> specific files. + * + * See lib/bitmap.c for more details. + */ + +/* + * The available bitmap operations and their rough meaning in the + * case that the bitmap is a single unsigned long are thus: + * + * Note that nbits should be always a compile time evaluable constant. + * Otherwise many inlines will generate horrible code. + * + * bitmap_zero(dst, nbits) *dst = 0UL + * bitmap_fill(dst, nbits) *dst = ~0UL + * bitmap_copy(dst, src, nbits) *dst = *src + * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2 + * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2 + * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2 + * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2) + * bitmap_complement(dst, src, nbits) *dst = ~(*src) + * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal? + * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap? + * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2? + * bitmap_empty(src, nbits) Are all bits zero in *src? + * bitmap_full(src, nbits) Are all bits set in *src? + * bitmap_weight(src, nbits) Hamming Weight: number set bits + * 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) + * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit) + * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap + * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz + * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf + * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf + * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf + * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf + * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region + * bitmap_release_region(bitmap, pos, order) Free specified bit region + * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region + */ + +/* + * Also the following operations in asm/bitops.h apply to bitmaps. + * + * set_bit(bit, addr) *addr |= bit + * clear_bit(bit, addr) *addr &= ~bit + * change_bit(bit, addr) *addr ^= bit + * test_bit(bit, addr) Is bit set in *addr? + * test_and_set_bit(bit, addr) Set bit and return old value + * test_and_clear_bit(bit, addr) Clear bit and return old value + * test_and_change_bit(bit, addr) Change bit and return old value + * find_first_zero_bit(addr, nbits) Position first zero bit in *addr + * find_first_bit(addr, nbits) Position first set bit in *addr + * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit + * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit + */ + +/* + * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used + * to declare an array named 'name' of just enough unsigned longs to + * contain all bit positions from 0 to 'bits' - 1. + */ + +/* + * lib/bitmap.c provides these functions: + */ + +extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits); +extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits); +extern int __bitmap_equal(const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int nbits); +extern void __bitmap_complement(unsigned long *dst, const unsigned long *src, + unsigned int nbits); +extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, + unsigned int shift, unsigned int nbits); +extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, + unsigned int shift, unsigned int nbits); +extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int nbits); +extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int nbits); +extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int nbits); +extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int nbits); +extern int __bitmap_intersects(const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int nbits); +extern int __bitmap_subset(const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int nbits); +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_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_parse(const char *buf, unsigned int buflen, int is_user, + unsigned long *dst, int nbits); +extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen, + unsigned long *dst, int nbits); +extern int bitmap_parselist(const char *buf, unsigned long *maskp, + int nmaskbits); +extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen, + unsigned long *dst, int nbits); +extern void bitmap_remap(unsigned long *dst, const unsigned long *src, + const unsigned long *old, const unsigned long *new, unsigned int nbits); +extern int bitmap_bitremap(int oldbit, + const unsigned long *old, const unsigned long *new, int bits); +extern void bitmap_onto(unsigned long *dst, const unsigned long *orig, + const unsigned long *relmap, unsigned int bits); +extern void bitmap_fold(unsigned long *dst, const unsigned long *orig, + unsigned int sz, unsigned int nbits); +extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order); +extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order); +extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order); +#ifdef __BIG_ENDIAN +extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits); +#else +#define bitmap_copy_le bitmap_copy +#endif +extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits); +extern int bitmap_print_to_pagebuf(bool list, char *buf, + const unsigned long *maskp, int nmaskbits); + +#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1))) +#define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1))) + +#define small_const_nbits(nbits) \ + (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG) + +static inline void bitmap_zero(unsigned long *dst, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + *dst = 0UL; + else { + unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); + memset(dst, 0, len); + } +} + +static inline void bitmap_fill(unsigned long *dst, unsigned int nbits) +{ + unsigned int nlongs = BITS_TO_LONGS(nbits); + if (!small_const_nbits(nbits)) { + unsigned int len = (nlongs - 1) * sizeof(unsigned long); + memset(dst, 0xff, len); + } + dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits); +} + +static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, + unsigned int nbits) +{ + if (small_const_nbits(nbits)) + *dst = *src; + else { + unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); + memcpy(dst, src, len); + } +} + +static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0; + return __bitmap_and(dst, src1, src2, nbits); +} + +static inline void bitmap_or(unsigned long *dst, const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + *dst = *src1 | *src2; + else + __bitmap_or(dst, src1, src2, nbits); +} + +static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + *dst = *src1 ^ *src2; + else + __bitmap_xor(dst, src1, src2, nbits); +} + +static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; + return __bitmap_andnot(dst, src1, src2, nbits); +} + +static inline void bitmap_complement(unsigned long *dst, const unsigned long *src, + unsigned int nbits) +{ + if (small_const_nbits(nbits)) + *dst = ~(*src); + else + __bitmap_complement(dst, src, nbits); +} + +static inline int bitmap_equal(const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); + else + return __bitmap_equal(src1, src2, nbits); +} + +static inline int bitmap_intersects(const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; + else + return __bitmap_intersects(src1, src2, nbits); +} + +static inline int bitmap_subset(const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits)); + else + return __bitmap_subset(src1, src2, nbits); +} + +static inline int bitmap_empty(const unsigned long *src, unsigned nbits) +{ + if (small_const_nbits(nbits)) + return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); + + return find_first_bit(src, nbits) == nbits; +} + +static inline int bitmap_full(const unsigned long *src, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits)); + + return find_first_zero_bit(src, nbits) == nbits; +} + +static inline int bitmap_weight(const unsigned long *src, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits)); + return __bitmap_weight(src, nbits); +} + +static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src, + unsigned int shift, int nbits) +{ + if (small_const_nbits(nbits)) + *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift; + else + __bitmap_shift_right(dst, src, shift, nbits); +} + +static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src, + unsigned int shift, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits); + else + __bitmap_shift_left(dst, src, shift, nbits); +} + +static inline int bitmap_parse(const char *buf, unsigned int buflen, + unsigned long *maskp, int nmaskbits) +{ + return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits); +} + +#endif /* __ASSEMBLY__ */ + +#endif /* __LINUX_BITMAP_H */ |