/* * Bitmap Module * * Copyright (C) 2010 Corentin Chary <corentin.chary@gmail.com> * * Mostly inspired by (stolen from) linux/bitmap.h and linux/bitops.h * * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. * See the COPYING.LIB file in the top-level directory. */ #ifndef BITMAP_H #define BITMAP_H #include "qemu-common.h" #include "bitops.h" /* * 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_empty(src, nbits) Are all bits zero in *src? * bitmap_full(src, nbits) Are all bits set in *src? * 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 */ /* * Also the following operations 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 */ #define BITMAP_LAST_WORD_MASK(nbits) \ ( \ ((nbits) % BITS_PER_LONG) ? \ (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \ ) #define DECLARE_BITMAP(name,bits) \ unsigned long name[BITS_TO_LONGS(bits)] #define small_nbits(nbits) \ ((nbits) <= BITS_PER_LONG) int slow_bitmap_empty(const unsigned long *bitmap, int bits); int slow_bitmap_full(const unsigned long *bitmap, int bits); int slow_bitmap_equal(const unsigned long *bitmap1, const unsigned long *bitmap2, int bits); void slow_bitmap_complement(unsigned long *dst, const unsigned long *src, int bits); void slow_bitmap_shift_right(unsigned long *dst, const unsigned long *src, int shift, int bits); void slow_bitmap_shift_left(unsigned long *dst, const unsigned long *src, int shift, int bits); int slow_bitmap_and(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, int bits); void slow_bitmap_or(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, int bits); void slow_bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, int bits); int slow_bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, int bits); int slow_bitmap_intersects(const unsigned long *bitmap1, const unsigned long *bitmap2, int bits); static inline unsigned long *bitmap_new(int nbits) { int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); return qemu_mallocz(len); } static inline void bitmap_zero(unsigned long *dst, int nbits) { if (small_nbits(nbits)) { *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 (!small_nbits(nbits)) { 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 (small_nbits(nbits)) { *dst = *src; } else { 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, int nbits) { if (small_nbits(nbits)) { return (*dst = *src1 & *src2) != 0; } return slow_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 (small_nbits(nbits)) { *dst = *src1 | *src2; } else { slow_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 (small_nbits(nbits)) { *dst = *src1 ^ *src2; } else { slow_bitmap_xor(dst, src1, src2, nbits); } } static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1, const unsigned long *src2, int nbits) { if (small_nbits(nbits)) { return (*dst = *src1 & ~(*src2)) != 0; } return slow_bitmap_andnot(dst, src1, src2, nbits); } static inline void bitmap_complement(unsigned long *dst, const unsigned long *src, int nbits) { if (small_nbits(nbits)) { *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits); } else { slow_bitmap_complement(dst, src, nbits); } } static inline int bitmap_equal(const unsigned long *src1, const unsigned long *src2, int nbits) { if (small_nbits(nbits)) { return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); } else { return slow_bitmap_equal(src1, src2, nbits); } } static inline int bitmap_empty(const unsigned long *src, int nbits) { if (small_nbits(nbits)) { return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); } else { return slow_bitmap_empty(src, nbits); } } static inline int bitmap_full(const unsigned long *src, int nbits) { if (small_nbits(nbits)) { return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits)); } else { return slow_bitmap_full(src, nbits); } } static inline int bitmap_intersects(const unsigned long *src1, const unsigned long *src2, int nbits) { if (small_nbits(nbits)) { return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; } else { return slow_bitmap_intersects(src1, src2, nbits); } } void bitmap_set(unsigned long *map, int i, int len); void bitmap_clear(unsigned long *map, int start, int nr); unsigned long bitmap_find_next_zero_area(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, unsigned long align_mask); #endif /* BITMAP_H */