/*
* 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/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_set_atomic(dst, pos, nbits) Set specified bit area with atomic ops
* bitmap_clear(dst, pos, nbits) Clear specified bit area
* bitmap_test_and_clear_atomic(dst, pos, nbits) Test and clear area
* bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area
* bitmap_to_le(dst, src, nbits) Convert bitmap to little endian
* bitmap_from_le(dst, src, nbits) Convert bitmap from little endian
* bitmap_copy_with_src_offset(dst, src, offset, nbits)
* *dst = *src (with an offset into src)
* bitmap_copy_with_dst_offset(dst, src, offset, nbits)
* *dst = *src (with an offset into dst)
*/
/*
* 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_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
#define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
#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, long bits);
int slow_bitmap_full(const unsigned long *bitmap, long bits);
int slow_bitmap_equal(const unsigned long *bitmap1,
const unsigned long *bitmap2, long bits);
void slow_bitmap_complement(unsigned long *dst, const unsigned long *src,
long bits);
int slow_bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
const unsigned long *bitmap2, long bits);
void slow_bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
const unsigned long *bitmap2, long bits);
void slow_bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
const unsigned long *bitmap2, long bits);
int slow_bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
const unsigned long *bitmap2, long bits);
int slow_bitmap_intersects(const unsigned long *bitmap1,
const unsigned long *bitmap2, long bits);
long slow_bitmap_count_one(const unsigned long *bitmap, long nbits);
static inline unsigned long *bitmap_try_new(long nbits)
{
long len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
return g_try_malloc0(len);
}
static inline unsigned long *bitmap_new(long nbits)
{
unsigned long *ptr = bitmap_try_new(nbits);
if (ptr == NULL) {
abort();
}
return ptr;
}
static inline void bitmap_zero(unsigned long *dst, long nbits)
{
if (small_nbits(nbits)) {
*dst = 0UL;
} else {
long len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
memset(dst, 0, len);
}
}
static inline void bitmap_fill(unsigned long *dst, long nbits)
{
size_t nlongs = BITS_TO_LONGS(nbits);
if (!small_nbits(nbits)) {
long 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,
long nbits)
{
if (small_nbits(nbits)) {
*dst = *src;
} else {
long 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, long 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, long 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, long 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, long 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,
long 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, long 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, long 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, long 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, long nbits)
{
if (small_nbits(nbits)) {
return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
} else {
return slow_bitmap_intersects(src1, src2, nbits);
}
}
static inline long bitmap_count_one(const unsigned long *bitmap, long nbits)
{
if (unlikely(!nbits)) {
return 0;
}
if (small_nbits(nbits)) {
return ctpopl(*bitmap & BITMAP_LAST_WORD_MASK(nbits));
} else {
return slow_bitmap_count_one(bitmap, nbits);
}
}
static inline long bitmap_count_one_with_offset(const unsigned long *bitmap,
long offset, long nbits)
{
long aligned_offset = QEMU_ALIGN_DOWN(offset, BITS_PER_LONG);
long redundant_bits = offset - aligned_offset;
long bits_to_count = nbits + redundant_bits;
const unsigned long *bitmap_start = bitmap +
aligned_offset / BITS_PER_LONG;
return bitmap_count_one(bitmap_start, bits_to_count) -
bitmap_count_one(bitmap_start, redundant_bits);
}
void bitmap_set(unsigned long *map, long i, long len);
void bitmap_set_atomic(unsigned long *map, long i, long len);
void bitmap_clear(unsigned long *map, long start, long nr);
bool bitmap_test_and_clear_atomic(unsigned long *map, long start, long nr);
void bitmap_copy_and_clear_atomic(unsigned long *dst, unsigned long *src,
long nr);
unsigned long bitmap_find_next_zero_area(unsigned long *map,
unsigned long size,
unsigned long start,
unsigned long nr,
unsigned long align_mask);
static inline unsigned long *bitmap_zero_extend(unsigned long *old,
long old_nbits, long new_nbits)
{
long new_len = BITS_TO_LONGS(new_nbits) * sizeof(unsigned long);
unsigned long *new = g_realloc(old, new_len);
bitmap_clear(new, old_nbits, new_nbits - old_nbits);
return new;
}
void bitmap_to_le(unsigned long *dst, const unsigned long *src,
long nbits);
void bitmap_from_le(unsigned long *dst, const unsigned long *src,
long nbits);
void bitmap_copy_with_src_offset(unsigned long *dst, const unsigned long *src,
unsigned long offset, unsigned long nbits);
void bitmap_copy_with_dst_offset(unsigned long *dst, const unsigned long *src,
unsigned long shift, unsigned long nbits);
#endif /* BITMAP_H */
