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 #include <linux/kernel.h>
10 
11 /*
12  * bitmaps provide bit arrays that consume one or more unsigned
13  * longs.  The bitmap interface and available operations are listed
14  * here, in bitmap.h
15  *
16  * Function implementations generic to all architectures are in
17  * lib/bitmap.c.  Functions implementations that are architecture
18  * specific are in various include/asm-<arch>/bitops.h headers
19  * and other arch/<arch> specific files.
20  *
21  * See lib/bitmap.c for more details.
22  */
23 
24 /*
25  * The available bitmap operations and their rough meaning in the
26  * case that the bitmap is a single unsigned long are thus:
27  *
28  * Note that nbits should be always a compile time evaluable constant.
29  * Otherwise many inlines will generate horrible code.
30  *
31  * bitmap_zero(dst, nbits)			*dst = 0UL
32  * bitmap_fill(dst, nbits)			*dst = ~0UL
33  * bitmap_copy(dst, src, nbits)			*dst = *src
34  * bitmap_and(dst, src1, src2, nbits)		*dst = *src1 & *src2
35  * bitmap_or(dst, src1, src2, nbits)		*dst = *src1 | *src2
36  * bitmap_xor(dst, src1, src2, nbits)		*dst = *src1 ^ *src2
37  * bitmap_andnot(dst, src1, src2, nbits)	*dst = *src1 & ~(*src2)
38  * bitmap_complement(dst, src, nbits)		*dst = ~(*src)
39  * bitmap_equal(src1, src2, nbits)		Are *src1 and *src2 equal?
40  * bitmap_intersects(src1, src2, nbits) 	Do *src1 and *src2 overlap?
41  * bitmap_subset(src1, src2, nbits)		Is *src1 a subset of *src2?
42  * bitmap_empty(src, nbits)			Are all bits zero in *src?
43  * bitmap_full(src, nbits)			Are all bits set in *src?
44  * bitmap_weight(src, nbits)			Hamming Weight: number set bits
45  * bitmap_set(dst, pos, nbits)			Set specified bit area
46  * bitmap_clear(dst, pos, nbits)		Clear specified bit area
47  * bitmap_find_next_zero_area(buf, len, pos, n, mask)	Find bit free area
48  * bitmap_shift_right(dst, src, n, nbits)	*dst = *src >> n
49  * bitmap_shift_left(dst, src, n, nbits)	*dst = *src << n
50  * bitmap_remap(dst, src, old, new, nbits)	*dst = map(old, new)(src)
51  * bitmap_bitremap(oldbit, old, new, nbits)	newbit = map(old, new)(oldbit)
52  * bitmap_onto(dst, orig, relmap, nbits)	*dst = orig relative to relmap
53  * bitmap_fold(dst, orig, sz, nbits)		dst bits = orig bits mod sz
54  * bitmap_scnprintf(buf, len, src, nbits)	Print bitmap src to buf
55  * bitmap_parse(buf, buflen, dst, nbits)	Parse bitmap dst from kernel buf
56  * bitmap_parse_user(ubuf, ulen, dst, nbits)	Parse bitmap dst from user buf
57  * bitmap_scnlistprintf(buf, len, src, nbits)	Print bitmap src as list to buf
58  * bitmap_parselist(buf, dst, nbits)		Parse bitmap dst from list
59  * bitmap_find_free_region(bitmap, bits, order)	Find and allocate bit region
60  * bitmap_release_region(bitmap, pos, order)	Free specified bit region
61  * bitmap_allocate_region(bitmap, pos, order)	Allocate specified bit region
62  */
63 
64 /*
65  * Also the following operations in asm/bitops.h apply to bitmaps.
66  *
67  * set_bit(bit, addr)			*addr |= bit
68  * clear_bit(bit, addr)			*addr &= ~bit
69  * change_bit(bit, addr)		*addr ^= bit
70  * test_bit(bit, addr)			Is bit set in *addr?
71  * test_and_set_bit(bit, addr)		Set bit and return old value
72  * test_and_clear_bit(bit, addr)	Clear bit and return old value
73  * test_and_change_bit(bit, addr)	Change bit and return old value
74  * find_first_zero_bit(addr, nbits)	Position first zero bit in *addr
75  * find_first_bit(addr, nbits)		Position first set bit in *addr
76  * find_next_zero_bit(addr, nbits, bit)	Position next zero bit in *addr >= bit
77  * find_next_bit(addr, nbits, bit)	Position next set bit in *addr >= bit
78  */
79 
80 /*
81  * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
82  * to declare an array named 'name' of just enough unsigned longs to
83  * contain all bit positions from 0 to 'bits' - 1.
84  */
85 
86 /*
87  * lib/bitmap.c provides these functions:
88  */
89 
90 extern int __bitmap_empty(const unsigned long *bitmap, int bits);
91 extern int __bitmap_full(const unsigned long *bitmap, int bits);
92 extern int __bitmap_equal(const unsigned long *bitmap1,
93                 	const unsigned long *bitmap2, int bits);
94 extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
95 			int bits);
96 extern void __bitmap_shift_right(unsigned long *dst,
97                         const unsigned long *src, int shift, int bits);
98 extern void __bitmap_shift_left(unsigned long *dst,
99                         const unsigned long *src, int shift, int bits);
100 extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
101 			const unsigned long *bitmap2, int bits);
102 extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
103 			const unsigned long *bitmap2, int bits);
104 extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
105 			const unsigned long *bitmap2, int bits);
106 extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
107 			const unsigned long *bitmap2, int bits);
108 extern int __bitmap_intersects(const unsigned long *bitmap1,
109 			const unsigned long *bitmap2, int bits);
110 extern int __bitmap_subset(const unsigned long *bitmap1,
111 			const unsigned long *bitmap2, int bits);
112 extern int __bitmap_weight(const unsigned long *bitmap, int bits);
113 
114 extern void bitmap_set(unsigned long *map, int i, int len);
115 extern void bitmap_clear(unsigned long *map, int start, int nr);
116 extern unsigned long bitmap_find_next_zero_area(unsigned long *map,
117 					 unsigned long size,
118 					 unsigned long start,
119 					 unsigned int nr,
120 					 unsigned long align_mask);
121 
122 extern int bitmap_scnprintf(char *buf, unsigned int len,
123 			const unsigned long *src, int nbits);
124 extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
125 			unsigned long *dst, int nbits);
126 extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
127 			unsigned long *dst, int nbits);
128 extern int bitmap_scnlistprintf(char *buf, unsigned int len,
129 			const unsigned long *src, int nbits);
130 extern int bitmap_parselist(const char *buf, unsigned long *maskp,
131 			int nmaskbits);
132 extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
133 		const unsigned long *old, const unsigned long *new, int bits);
134 extern int bitmap_bitremap(int oldbit,
135 		const unsigned long *old, const unsigned long *new, int bits);
136 extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
137 		const unsigned long *relmap, int bits);
138 extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
139 		int sz, int bits);
140 extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
141 extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
142 extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
143 extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits);
144 
145 #define BITMAP_LAST_WORD_MASK(nbits)					\
146 (									\
147 	((nbits) % BITS_PER_LONG) ?					\
148 		(1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL		\
149 )
150 
151 #define small_const_nbits(nbits) \
152 	(__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
153 
bitmap_zero(unsigned long * dst,int nbits)154 static inline void bitmap_zero(unsigned long *dst, int nbits)
155 {
156 	if (small_const_nbits(nbits))
157 		*dst = 0UL;
158 	else {
159 		int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
160 		memset(dst, 0, len);
161 	}
162 }
163 
bitmap_fill(unsigned long * dst,int nbits)164 static inline void bitmap_fill(unsigned long *dst, int nbits)
165 {
166 	size_t nlongs = BITS_TO_LONGS(nbits);
167 	if (!small_const_nbits(nbits)) {
168 		int len = (nlongs - 1) * sizeof(unsigned long);
169 		memset(dst, 0xff,  len);
170 	}
171 	dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
172 }
173 
bitmap_copy(unsigned long * dst,const unsigned long * src,int nbits)174 static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
175 			int nbits)
176 {
177 	if (small_const_nbits(nbits))
178 		*dst = *src;
179 	else {
180 		int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
181 		memcpy(dst, src, len);
182 	}
183 }
184 
bitmap_and(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,int nbits)185 static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
186 			const unsigned long *src2, int nbits)
187 {
188 	if (small_const_nbits(nbits))
189 		return (*dst = *src1 & *src2) != 0;
190 	return __bitmap_and(dst, src1, src2, nbits);
191 }
192 
bitmap_or(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,int nbits)193 static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
194 			const unsigned long *src2, int nbits)
195 {
196 	if (small_const_nbits(nbits))
197 		*dst = *src1 | *src2;
198 	else
199 		__bitmap_or(dst, src1, src2, nbits);
200 }
201 
bitmap_xor(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,int nbits)202 static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
203 			const unsigned long *src2, int nbits)
204 {
205 	if (small_const_nbits(nbits))
206 		*dst = *src1 ^ *src2;
207 	else
208 		__bitmap_xor(dst, src1, src2, nbits);
209 }
210 
bitmap_andnot(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,int nbits)211 static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1,
212 			const unsigned long *src2, int nbits)
213 {
214 	if (small_const_nbits(nbits))
215 		return (*dst = *src1 & ~(*src2)) != 0;
216 	return __bitmap_andnot(dst, src1, src2, nbits);
217 }
218 
bitmap_complement(unsigned long * dst,const unsigned long * src,int nbits)219 static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
220 			int nbits)
221 {
222 	if (small_const_nbits(nbits))
223 		*dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits);
224 	else
225 		__bitmap_complement(dst, src, nbits);
226 }
227 
bitmap_equal(const unsigned long * src1,const unsigned long * src2,int nbits)228 static inline int bitmap_equal(const unsigned long *src1,
229 			const unsigned long *src2, int nbits)
230 {
231 	if (small_const_nbits(nbits))
232 		return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
233 	else
234 		return __bitmap_equal(src1, src2, nbits);
235 }
236 
bitmap_intersects(const unsigned long * src1,const unsigned long * src2,int nbits)237 static inline int bitmap_intersects(const unsigned long *src1,
238 			const unsigned long *src2, int nbits)
239 {
240 	if (small_const_nbits(nbits))
241 		return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
242 	else
243 		return __bitmap_intersects(src1, src2, nbits);
244 }
245 
bitmap_subset(const unsigned long * src1,const unsigned long * src2,int nbits)246 static inline int bitmap_subset(const unsigned long *src1,
247 			const unsigned long *src2, int nbits)
248 {
249 	if (small_const_nbits(nbits))
250 		return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
251 	else
252 		return __bitmap_subset(src1, src2, nbits);
253 }
254 
bitmap_empty(const unsigned long * src,int nbits)255 static inline int bitmap_empty(const unsigned long *src, int nbits)
256 {
257 	if (small_const_nbits(nbits))
258 		return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
259 	else
260 		return __bitmap_empty(src, nbits);
261 }
262 
bitmap_full(const unsigned long * src,int nbits)263 static inline int bitmap_full(const unsigned long *src, int nbits)
264 {
265 	if (small_const_nbits(nbits))
266 		return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
267 	else
268 		return __bitmap_full(src, nbits);
269 }
270 
bitmap_weight(const unsigned long * src,int nbits)271 static inline int bitmap_weight(const unsigned long *src, int nbits)
272 {
273 	if (small_const_nbits(nbits))
274 		return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
275 	return __bitmap_weight(src, nbits);
276 }
277 
bitmap_shift_right(unsigned long * dst,const unsigned long * src,int n,int nbits)278 static inline void bitmap_shift_right(unsigned long *dst,
279 			const unsigned long *src, int n, int nbits)
280 {
281 	if (small_const_nbits(nbits))
282 		*dst = *src >> n;
283 	else
284 		__bitmap_shift_right(dst, src, n, nbits);
285 }
286 
bitmap_shift_left(unsigned long * dst,const unsigned long * src,int n,int nbits)287 static inline void bitmap_shift_left(unsigned long *dst,
288 			const unsigned long *src, int n, int nbits)
289 {
290 	if (small_const_nbits(nbits))
291 		*dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
292 	else
293 		__bitmap_shift_left(dst, src, n, nbits);
294 }
295 
bitmap_parse(const char * buf,unsigned int buflen,unsigned long * maskp,int nmaskbits)296 static inline int bitmap_parse(const char *buf, unsigned int buflen,
297 			unsigned long *maskp, int nmaskbits)
298 {
299 	return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
300 }
301 
302 #endif /* __ASSEMBLY__ */
303 
304 #endif /* __LINUX_BITMAP_H */
305