[qemu.git] / include / qemu / bitmap.h

/*
 * Bitmap Module
 *
 * Copyright (C) 2010 Corentin Chary <[email protected]>
 *
 * 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
 */

/*
 * 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, 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);

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);
    }
}

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);
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;
}

#endif /* BITMAP_H */
Commit	Line	Data
e0e53b2f CC	1	/*
	2	* Bitmap Module
	3	*
	4	* Copyright (C) 2010 Corentin Chary <[email protected]>
	5	*
	6	* Mostly inspired by (stolen from) linux/bitmap.h and linux/bitops.h
	7	*
	8	* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
	9	* See the COPYING.LIB file in the top-level directory.
	10	*/
	11
	12	#ifndef BITMAP_H
	13	#define BITMAP_H
	14
d6aaddfe	15
1de7afc9	16	#include "qemu/bitops.h"
e0e53b2f CC	17
	18	/*
	19	* The available bitmap operations and their rough meaning in the
	20	* case that the bitmap is a single unsigned long are thus:
	21	*
	22	* Note that nbits should be always a compile time evaluable constant.
	23	* Otherwise many inlines will generate horrible code.
	24	*
	25	* bitmap_zero(dst, nbits) *dst = 0UL
	26	* bitmap_fill(dst, nbits) *dst = ~0UL
	27	* bitmap_copy(dst, src, nbits) dst = src
	28	* bitmap_and(dst, src1, src2, nbits) dst = src1 & *src2
	29	* bitmap_or(dst, src1, src2, nbits) dst = src1 \| *src2
	30	* bitmap_xor(dst, src1, src2, nbits) dst = src1 ^ *src2
	31	* bitmap_andnot(dst, src1, src2, nbits) dst = src1 & ~(*src2)
	32	* bitmap_complement(dst, src, nbits) dst = ~(src)
	33	* bitmap_equal(src1, src2, nbits) Are src1 and src2 equal?
9c22687e	34	* bitmap_intersects(src1, src2, nbits) Do src1 and src2 overlap?
e0e53b2f CC	35	* bitmap_empty(src, nbits) Are all bits zero in *src?
	36	* bitmap_full(src, nbits) Are all bits set in *src?
	37	* bitmap_set(dst, pos, nbits) Set specified bit area
9f02cfc8	38	* bitmap_set_atomic(dst, pos, nbits) Set specified bit area with atomic ops
e0e53b2f	39	* bitmap_clear(dst, pos, nbits) Clear specified bit area
36546e5b	40	* bitmap_test_and_clear_atomic(dst, pos, nbits) Test and clear area
e0e53b2f CC	41	* bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area
	42	*/
	43
	44	/*
	45	* Also the following operations apply to bitmaps.
	46	*
	47	* set_bit(bit, addr) *addr \|= bit
	48	* clear_bit(bit, addr) *addr &= ~bit
	49	* change_bit(bit, addr) *addr ^= bit
	50	* test_bit(bit, addr) Is bit set in *addr?
	51	* test_and_set_bit(bit, addr) Set bit and return old value
	52	* test_and_clear_bit(bit, addr) Clear bit and return old value
	53	* test_and_change_bit(bit, addr) Change bit and return old value
	54	* find_first_zero_bit(addr, nbits) Position first zero bit in *addr
	55	* find_first_bit(addr, nbits) Position first set bit in *addr
	56	* find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
	57	* find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
	58	*/
	59
	60	#define BITMAP_LAST_WORD_MASK(nbits) \
	61	( \
	62	((nbits) % BITS_PER_LONG) ? \
	63	(1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
	64	)
	65
	66	#define DECLARE_BITMAP(name,bits) \
9c22687e	67	unsigned long name[BITS_TO_LONGS(bits)]
e0e53b2f CC	68
e0e53b2f CC	69	#define small_nbits(nbits) \
9c22687e	70	((nbits) <= BITS_PER_LONG)
e0e53b2f	71
9c22687e JQ	72	int slow_bitmap_empty(const unsigned long *bitmap, long bits);
9c22687e JQ	73	int slow_bitmap_full(const unsigned long *bitmap, long bits);
e0e53b2f	74	int slow_bitmap_equal(const unsigned long *bitmap1,
9c22687e	75	const unsigned long *bitmap2, long bits);
e0e53b2f	76	void slow_bitmap_complement(unsigned long dst, const unsigned long src,
9c22687e	77	long bits);
e0e53b2f	78	int slow_bitmap_and(unsigned long dst, const unsigned long bitmap1,
9c22687e	79	const unsigned long *bitmap2, long bits);
e0e53b2f	80	void slow_bitmap_or(unsigned long dst, const unsigned long bitmap1,
9c22687e	81	const unsigned long *bitmap2, long bits);
e0e53b2f	82	void slow_bitmap_xor(unsigned long dst, const unsigned long bitmap1,
9c22687e	83	const unsigned long *bitmap2, long bits);
e0e53b2f	84	int slow_bitmap_andnot(unsigned long dst, const unsigned long bitmap1,
9c22687e	85	const unsigned long *bitmap2, long bits);
e0e53b2f	86	int slow_bitmap_intersects(const unsigned long *bitmap1,
9c22687e	87	const unsigned long *bitmap2, long bits);
e0e53b2f	88
be4d57c1	89	static inline unsigned long *bitmap_try_new(long nbits)
e0e53b2f	90	{
9c22687e	91	long len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
be4d57c1 PL	92	return g_try_malloc0(len);
	93	}
	94
	95	static inline unsigned long *bitmap_new(long nbits)
	96	{
	97	unsigned long *ptr = bitmap_try_new(nbits);
	98	if (ptr == NULL) {
	99	abort();
	100	}
	101	return ptr;
e0e53b2f CC	102	}
e0e53b2f CC	103
9c22687e	104	static inline void bitmap_zero(unsigned long *dst, long nbits)
e0e53b2f CC	105	{
	106	if (small_nbits(nbits)) {
	107	*dst = 0UL;
	108	} else {
9c22687e	109	long len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
e0e53b2f CC	110	memset(dst, 0, len);
	111	}
	112	}
	113
9c22687e	114	static inline void bitmap_fill(unsigned long *dst, long nbits)
e0e53b2f CC	115	{
	116	size_t nlongs = BITS_TO_LONGS(nbits);
	117	if (!small_nbits(nbits)) {
9c22687e	118	long len = (nlongs - 1) * sizeof(unsigned long);
e0e53b2f CC	119	memset(dst, 0xff, len);
	120	}
	121	dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
	122	}
	123
	124	static inline void bitmap_copy(unsigned long dst, const unsigned long src,
9c22687e	125	long nbits)
e0e53b2f CC	126	{
	127	if (small_nbits(nbits)) {
	128	dst = src;
	129	} else {
9c22687e	130	long len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
e0e53b2f CC	131	memcpy(dst, src, len);
	132	}
	133	}
	134
	135	static inline int bitmap_and(unsigned long dst, const unsigned long src1,
9c22687e	136	const unsigned long *src2, long nbits)
e0e53b2f CC	137	{
	138	if (small_nbits(nbits)) {
	139	return (dst = src1 & *src2) != 0;
	140	}
	141	return slow_bitmap_and(dst, src1, src2, nbits);
	142	}
	143
	144	static inline void bitmap_or(unsigned long dst, const unsigned long src1,
9c22687e	145	const unsigned long *src2, long nbits)
e0e53b2f CC	146	{
	147	if (small_nbits(nbits)) {
	148	dst = src1 \| *src2;
	149	} else {
	150	slow_bitmap_or(dst, src1, src2, nbits);
	151	}
	152	}
	153
	154	static inline void bitmap_xor(unsigned long dst, const unsigned long src1,
9c22687e	155	const unsigned long *src2, long nbits)
e0e53b2f CC	156	{
	157	if (small_nbits(nbits)) {
	158	dst = src1 ^ *src2;
	159	} else {
	160	slow_bitmap_xor(dst, src1, src2, nbits);
	161	}
	162	}
	163
	164	static inline int bitmap_andnot(unsigned long dst, const unsigned long src1,
9c22687e	165	const unsigned long *src2, long nbits)
e0e53b2f CC	166	{
	167	if (small_nbits(nbits)) {
	168	return (dst = src1 & ~(*src2)) != 0;
	169	}
	170	return slow_bitmap_andnot(dst, src1, src2, nbits);
	171	}
	172
9c22687e JQ	173	static inline void bitmap_complement(unsigned long *dst,
	174	const unsigned long *src,
	175	long nbits)
e0e53b2f CC	176	{
	177	if (small_nbits(nbits)) {
	178	dst = ~(src) & BITMAP_LAST_WORD_MASK(nbits);
	179	} else {
	180	slow_bitmap_complement(dst, src, nbits);
	181	}
	182	}
	183
	184	static inline int bitmap_equal(const unsigned long *src1,
9c22687e	185	const unsigned long *src2, long nbits)
e0e53b2f CC	186	{
	187	if (small_nbits(nbits)) {
	188	return ! ((src1 ^ src2) & BITMAP_LAST_WORD_MASK(nbits));
	189	} else {
	190	return slow_bitmap_equal(src1, src2, nbits);
	191	}
	192	}
	193
9c22687e	194	static inline int bitmap_empty(const unsigned long *src, long nbits)
e0e53b2f CC	195	{
	196	if (small_nbits(nbits)) {
	197	return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
	198	} else {
	199	return slow_bitmap_empty(src, nbits);
	200	}
	201	}
	202
9c22687e	203	static inline int bitmap_full(const unsigned long *src, long nbits)
e0e53b2f CC	204	{
	205	if (small_nbits(nbits)) {
	206	return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
	207	} else {
	208	return slow_bitmap_full(src, nbits);
	209	}
	210	}
	211
	212	static inline int bitmap_intersects(const unsigned long *src1,
9c22687e	213	const unsigned long *src2, long nbits)
e0e53b2f CC	214	{
	215	if (small_nbits(nbits)) {
	216	return ((src1 & src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
	217	} else {
	218	return slow_bitmap_intersects(src1, src2, nbits);
	219	}
	220	}
	221
9c22687e	222	void bitmap_set(unsigned long *map, long i, long len);
9f02cfc8	223	void bitmap_set_atomic(unsigned long *map, long i, long len);
9c22687e	224	void bitmap_clear(unsigned long *map, long start, long nr);
36546e5b	225	bool bitmap_test_and_clear_atomic(unsigned long *map, long start, long nr);
e0e53b2f	226	unsigned long bitmap_find_next_zero_area(unsigned long *map,
9c22687e JQ	227	unsigned long size,
	228	unsigned long start,
	229	unsigned long nr,
	230	unsigned long align_mask);
e0e53b2f	231
164590a6 JQ	232	static inline unsigned long bitmap_zero_extend(unsigned long old,
	233	long old_nbits, long new_nbits)
	234	{
	235	long new_len = BITS_TO_LONGS(new_nbits) * sizeof(unsigned long);
	236	unsigned long *new = g_realloc(old, new_len);
	237	bitmap_clear(new, old_nbits, new_nbits - old_nbits);
	238	return new;
	239	}
	240
e0e53b2f	241	#endif /* BITMAP_H */