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Diffstat (limited to 'include/linux/bitmap.h')
| -rw-r--r-- | include/linux/bitmap.h | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h new file mode 100644 index 00000000000..86dd5502b05 --- /dev/null +++ b/include/linux/bitmap.h @@ -0,0 +1,261 @@ +#ifndef __LINUX_BITMAP_H +#define __LINUX_BITMAP_H + +#ifndef __ASSEMBLY__ + +#include <linux/types.h> +#include <linux/bitops.h> +#include <linux/string.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: + * + * 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_shift_right(dst, src, n, nbits) *dst = *src >> n + * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n + * bitmap_scnprintf(buf, len, src, nbits) Print bitmap src to buf + * bitmap_parse(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf + * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf + * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from list + */ + +/* + * 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, int bits); +extern int __bitmap_full(const unsigned long *bitmap, int bits); +extern int __bitmap_equal(const unsigned long *bitmap1, + const unsigned long *bitmap2, int bits); +extern void __bitmap_complement(unsigned long *dst, const unsigned long *src, + int bits); +extern void __bitmap_shift_right(unsigned long *dst, + const unsigned long *src, int shift, int bits); +extern void __bitmap_shift_left(unsigned long *dst, + const unsigned long *src, int shift, int bits); +extern void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, int bits); +extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, int bits); +extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, int bits); +extern void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, int bits); +extern int __bitmap_intersects(const unsigned long *bitmap1, + const unsigned long *bitmap2, int bits); +extern int __bitmap_subset(const unsigned long *bitmap1, + const unsigned long *bitmap2, int bits); +extern int __bitmap_weight(const unsigned long *bitmap, int bits); + +extern int bitmap_scnprintf(char *buf, unsigned int len, + const unsigned long *src, int nbits); +extern int bitmap_parse(const char __user *ubuf, unsigned int ulen, + unsigned long *dst, int nbits); +extern int bitmap_scnlistprintf(char *buf, unsigned int len, + const unsigned long *src, int nbits); +extern int bitmap_parselist(const char *buf, unsigned long *maskp, + int nmaskbits); +extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order); +extern void bitmap_release_region(unsigned long *bitmap, int pos, int order); +extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order); + +#define BITMAP_LAST_WORD_MASK(nbits) \ +( \ + ((nbits) % BITS_PER_LONG) ? \ + (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \ +) + +static inline void bitmap_zero(unsigned long *dst, int nbits) +{ + if (nbits <= BITS_PER_LONG) + *dst = 0UL; + else { + int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); + memset(dst, 0, len); + } +} + +static inline void bitmap_fill(unsigned long *dst, int nbits) +{ + size_t nlongs = BITS_TO_LONGS(nbits); + if (nlongs > 1) { + 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, + int nbits) +{ + if (nbits <= BITS_PER_LONG) + *dst = *src; + else { + int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); + memcpy(dst, src, len); + } +} + +static inline void bitmap_and(unsigned long *dst, const unsigned long *src1, + const unsigned long *src2, int nbits) +{ + if (nbits <= BITS_PER_LONG) + *dst = *src1 & *src2; + else + __bitmap_and(dst, src1, src2, nbits); +} + +static inline void bitmap_or(unsigned long *dst, const unsigned long *src1, + const unsigned long *src2, int nbits) +{ + if (nbits <= BITS_PER_LONG) + *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, int nbits) +{ + if (nbits <= BITS_PER_LONG) + *dst = *src1 ^ *src2; + else + __bitmap_xor(dst, src1, src2, nbits); +} + +static inline void bitmap_andnot(unsigned long *dst, const unsigned long *src1, + const unsigned long *src2, int nbits) +{ + if (nbits <= BITS_PER_LONG) + *dst = *src1 & ~(*src2); + else + __bitmap_andnot(dst, src1, src2, nbits); +} + +static inline void bitmap_complement(unsigned long *dst, const unsigned long *src, + int nbits) +{ + if (nbits <= BITS_PER_LONG) + *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits); + else + __bitmap_complement(dst, src, nbits); +} + +static inline int bitmap_equal(const unsigned long *src1, + const unsigned long *src2, int nbits) +{ + if (nbits <= BITS_PER_LONG) + 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, int nbits) +{ + if (nbits <= BITS_PER_LONG) + 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, int nbits) +{ + if (nbits <= BITS_PER_LONG) + return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits)); + else + return __bitmap_subset(src1, src2, nbits); +} + +static inline int bitmap_empty(const unsigned long *src, int nbits) +{ + if (nbits <= BITS_PER_LONG) + return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); + else + return __bitmap_empty(src, nbits); +} + +static inline int bitmap_full(const unsigned long *src, int nbits) +{ + if (nbits <= BITS_PER_LONG) + return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits)); + else + return __bitmap_full(src, nbits); +} + +static inline int bitmap_weight(const unsigned long *src, int nbits) +{ + return __bitmap_weight(src, nbits); +} + +static inline void bitmap_shift_right(unsigned long *dst, + const unsigned long *src, int n, int nbits) +{ + if (nbits <= BITS_PER_LONG) + *dst = *src >> n; + else + __bitmap_shift_right(dst, src, n, nbits); +} + +static inline void bitmap_shift_left(unsigned long *dst, + const unsigned long *src, int n, int nbits) +{ + if (nbits <= BITS_PER_LONG) + *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits); + else + __bitmap_shift_left(dst, src, n, nbits); +} + +#endif /* __ASSEMBLY__ */ + +#endif /* __LINUX_BITMAP_H */ |