1#ifndef __LINUX_BITMAP_H
2#define __LINUX_BITMAP_H
3
4#ifndef __ASSEMBLY__
5
6#include <linux/types.h>
7#include <linux/bitops.h>
8#include <linux/string.h>
9
10/*
11 * bitmaps provide bit arrays that consume one or more unsigned
12 * longs.  The bitmap interface and available operations are listed
13 * here, in bitmap.h
14 *
15 * Function implementations generic to all architectures are in
16 * lib/bitmap.c.  Functions implementations that are architecture
17 * specific are in various include/asm-<arch>/bitops.h headers
18 * and other arch/<arch> specific files.
19 *
20 * See lib/bitmap.c for more details.
21 */
22
23/*
24 * The available bitmap operations and their rough meaning in the
25 * case that the bitmap is a single unsigned long are thus:
26 *
27 * Note that nbits should be always a compile time evaluable constant.
28 * Otherwise many inlines will generate horrible code.
29 *
30 * bitmap_zero(dst, nbits)			*dst = 0UL
31 * bitmap_fill(dst, nbits)			*dst = ~0UL
32 * bitmap_copy(dst, src, nbits)			*dst = *src
33 * bitmap_and(dst, src1, src2, nbits)		*dst = *src1 & *src2
34 * bitmap_or(dst, src1, src2, nbits)		*dst = *src1 | *src2
35 * bitmap_xor(dst, src1, src2, nbits)		*dst = *src1 ^ *src2
36 * bitmap_andnot(dst, src1, src2, nbits)	*dst = *src1 & ~(*src2)
37 * bitmap_complement(dst, src, nbits)		*dst = ~(*src)
38 * bitmap_equal(src1, src2, nbits)		Are *src1 and *src2 equal?
39 * bitmap_intersects(src1, src2, nbits) 	Do *src1 and *src2 overlap?
40 * bitmap_subset(src1, src2, nbits)		Is *src1 a subset of *src2?
41 * bitmap_empty(src, nbits)			Are all bits zero in *src?
42 * bitmap_full(src, nbits)			Are all bits set in *src?
43 * bitmap_weight(src, nbits)			Hamming Weight: number set bits
44 * bitmap_shift_right(dst, src, n, nbits)	*dst = *src >> n
45 * bitmap_shift_left(dst, src, n, nbits)	*dst = *src << n
46 * bitmap_remap(dst, src, old, new, nbits)	*dst = map(old, new)(src)
47 * bitmap_bitremap(oldbit, old, new, nbits)	newbit = map(old, new)(oldbit)
48 * bitmap_scnprintf(buf, len, src, nbits)	Print bitmap src to buf
49 * bitmap_parse(ubuf, ulen, dst, nbits)		Parse bitmap dst from user buf
50 * bitmap_scnlistprintf(buf, len, src, nbits)	Print bitmap src as list to buf
51 * bitmap_parselist(buf, dst, nbits)		Parse bitmap dst from list
52 * bitmap_find_free_region(bitmap, bits, order)	Find and allocate bit region
53 * bitmap_release_region(bitmap, pos, order)	Free specified bit region
54 * bitmap_allocate_region(bitmap, pos, order)	Allocate specified bit region
55 */
56
57/*
58 * Also the following operations in asm/bitops.h apply to bitmaps.
59 *
60 * set_bit(bit, addr)			*addr |= bit
61 * clear_bit(bit, addr)			*addr &= ~bit
62 * change_bit(bit, addr)		*addr ^= bit
63 * test_bit(bit, addr)			Is bit set in *addr?
64 * test_and_set_bit(bit, addr)		Set bit and return old value
65 * test_and_clear_bit(bit, addr)	Clear bit and return old value
66 * test_and_change_bit(bit, addr)	Change bit and return old value
67 * find_first_zero_bit(addr, nbits)	Position first zero bit in *addr
68 * find_first_bit(addr, nbits)		Position first set bit in *addr
69 * find_next_zero_bit(addr, nbits, bit)	Position next zero bit in *addr >= bit
70 * find_next_bit(addr, nbits, bit)	Position next set bit in *addr >= bit
71 */
72
73/*
74 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
75 * to declare an array named 'name' of just enough unsigned longs to
76 * contain all bit positions from 0 to 'bits' - 1.
77 */
78
79/*
80 * lib/bitmap.c provides these functions:
81 */
82
83extern int __bitmap_empty(const unsigned long *bitmap, int bits);
84extern int __bitmap_full(const unsigned long *bitmap, int bits);
85extern int __bitmap_equal(const unsigned long *bitmap1,
86                	const unsigned long *bitmap2, int bits);
87extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
88			int bits);
89extern void __bitmap_shift_right(unsigned long *dst,
90                        const unsigned long *src, int shift, int bits);
91extern void __bitmap_shift_left(unsigned long *dst,
92                        const unsigned long *src, int shift, int bits);
93extern void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
94			const unsigned long *bitmap2, int bits);
95extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
96			const unsigned long *bitmap2, int bits);
97extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
98			const unsigned long *bitmap2, int bits);
99extern void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
100			const unsigned long *bitmap2, int bits);
101extern int __bitmap_intersects(const unsigned long *bitmap1,
102			const unsigned long *bitmap2, int bits);
103extern int __bitmap_subset(const unsigned long *bitmap1,
104			const unsigned long *bitmap2, int bits);
105extern int __bitmap_weight(const unsigned long *bitmap, int bits);
106
107extern int bitmap_scnprintf(char *buf, unsigned int len,
108			const unsigned long *src, int nbits);
109extern int bitmap_parse(const char __user *ubuf, unsigned int ulen,
110			unsigned long *dst, int nbits);
111extern int bitmap_scnlistprintf(char *buf, unsigned int len,
112			const unsigned long *src, int nbits);
113extern int bitmap_parselist(const char *buf, unsigned long *maskp,
114			int nmaskbits);
115extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
116		const unsigned long *old, const unsigned long *new, int bits);
117extern int bitmap_bitremap(int oldbit,
118		const unsigned long *old, const unsigned long *new, int bits);
119extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
120extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
121extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
122
123#define BITMAP_LAST_WORD_MASK(nbits)					\
124(									\
125	((nbits) % BITS_PER_LONG) ?					\
126		(1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL		\
127)
128
129static inline void bitmap_zero(unsigned long *dst, int nbits)
130{
131	if (nbits <= BITS_PER_LONG)
132		*dst = 0UL;
133	else {
134		int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
135		memset(dst, 0, len);
136	}
137}
138
139static inline void bitmap_fill(unsigned long *dst, int nbits)
140{
141	size_t nlongs = BITS_TO_LONGS(nbits);
142	if (nlongs > 1) {
143		int len = (nlongs - 1) * sizeof(unsigned long);
144		memset(dst, 0xff,  len);
145	}
146	dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
147}
148
149static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
150			int nbits)
151{
152	if (nbits <= BITS_PER_LONG)
153		*dst = *src;
154	else {
155		int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
156		memcpy(dst, src, len);
157	}
158}
159
160static inline void bitmap_and(unsigned long *dst, const unsigned long *src1,
161			const unsigned long *src2, int nbits)
162{
163	if (nbits <= BITS_PER_LONG)
164		*dst = *src1 & *src2;
165	else
166		__bitmap_and(dst, src1, src2, nbits);
167}
168
169static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
170			const unsigned long *src2, int nbits)
171{
172	if (nbits <= BITS_PER_LONG)
173		*dst = *src1 | *src2;
174	else
175		__bitmap_or(dst, src1, src2, nbits);
176}
177
178static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
179			const unsigned long *src2, int nbits)
180{
181	if (nbits <= BITS_PER_LONG)
182		*dst = *src1 ^ *src2;
183	else
184		__bitmap_xor(dst, src1, src2, nbits);
185}
186
187static inline void bitmap_andnot(unsigned long *dst, const unsigned long *src1,
188			const unsigned long *src2, int nbits)
189{
190	if (nbits <= BITS_PER_LONG)
191		*dst = *src1 & ~(*src2);
192	else
193		__bitmap_andnot(dst, src1, src2, nbits);
194}
195
196static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
197			int nbits)
198{
199	if (nbits <= BITS_PER_LONG)
200		*dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits);
201	else
202		__bitmap_complement(dst, src, nbits);
203}
204
205static inline int bitmap_equal(const unsigned long *src1,
206			const unsigned long *src2, int nbits)
207{
208	if (nbits <= BITS_PER_LONG)
209		return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
210	else
211		return __bitmap_equal(src1, src2, nbits);
212}
213
214static inline int bitmap_intersects(const unsigned long *src1,
215			const unsigned long *src2, int nbits)
216{
217	if (nbits <= BITS_PER_LONG)
218		return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
219	else
220		return __bitmap_intersects(src1, src2, nbits);
221}
222
223static inline int bitmap_subset(const unsigned long *src1,
224			const unsigned long *src2, int nbits)
225{
226	if (nbits <= BITS_PER_LONG)
227		return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
228	else
229		return __bitmap_subset(src1, src2, nbits);
230}
231
232static inline int bitmap_empty(const unsigned long *src, int nbits)
233{
234	if (nbits <= BITS_PER_LONG)
235		return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
236	else
237		return __bitmap_empty(src, nbits);
238}
239
240static inline int bitmap_full(const unsigned long *src, int nbits)
241{
242	if (nbits <= BITS_PER_LONG)
243		return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
244	else
245		return __bitmap_full(src, nbits);
246}
247
248static inline int bitmap_weight(const unsigned long *src, int nbits)
249{
250	if (nbits <= BITS_PER_LONG)
251		return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
252	return __bitmap_weight(src, nbits);
253}
254
255static inline void bitmap_shift_right(unsigned long *dst,
256			const unsigned long *src, int n, int nbits)
257{
258	if (nbits <= BITS_PER_LONG)
259		*dst = *src >> n;
260	else
261		__bitmap_shift_right(dst, src, n, nbits);
262}
263
264static inline void bitmap_shift_left(unsigned long *dst,
265			const unsigned long *src, int n, int nbits)
266{
267	if (nbits <= BITS_PER_LONG)
268		*dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
269	else
270		__bitmap_shift_left(dst, src, n, nbits);
271}
272
273#endif /* __ASSEMBLY__ */
274
275#endif /* __LINUX_BITMAP_H */
276