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_find_next_zero_area_off(buf, len, pos, n, mask) as above
49 * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
50 * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
51 * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
52 * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
53 * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
54 * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz
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_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf
58 * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf
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 * Allocation and deallocation of bitmap.
88 * Provided in lib/bitmap.c to avoid circular dependency.
89 */
90 extern unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags);
91 extern unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags);
92 extern void bitmap_free(const unsigned long *bitmap);
93
94 /*
95 * lib/bitmap.c provides these functions:
96 */
97
98 extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits);
99 extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits);
100 extern int __bitmap_equal(const unsigned long *bitmap1,
101 const unsigned long *bitmap2, unsigned int nbits);
102 extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
103 unsigned int nbits);
104 extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src,
105 unsigned int shift, unsigned int nbits);
106 extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src,
107 unsigned int shift, unsigned int nbits);
108 extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
109 const unsigned long *bitmap2, unsigned int nbits);
110 extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
111 const unsigned long *bitmap2, unsigned int nbits);
112 extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
113 const unsigned long *bitmap2, unsigned int nbits);
114 extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
115 const unsigned long *bitmap2, unsigned int nbits);
116 extern int __bitmap_intersects(const unsigned long *bitmap1,
117 const unsigned long *bitmap2, unsigned int nbits);
118 extern int __bitmap_subset(const unsigned long *bitmap1,
119 const unsigned long *bitmap2, unsigned int nbits);
120 extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
121
122 extern void bitmap_set(unsigned long *map, unsigned int start, int len);
123 extern void bitmap_clear(unsigned long *map, unsigned int start, int len);
124
125 extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
126 unsigned long size,
127 unsigned long start,
128 unsigned int nr,
129 unsigned long align_mask,
130 unsigned long align_offset);
131
132 /**
133 * bitmap_find_next_zero_area - find a contiguous aligned zero area
134 * @map: The address to base the search on
135 * @size: The bitmap size in bits
136 * @start: The bitnumber to start searching at
137 * @nr: The number of zeroed bits we're looking for
138 * @align_mask: Alignment mask for zero area
139 *
140 * The @align_mask should be one less than a power of 2; the effect is that
141 * the bit offset of all zero areas this function finds is multiples of that
142 * power of 2. A @align_mask of 0 means no alignment is required.
143 */
144 static inline unsigned long
bitmap_find_next_zero_area(unsigned long * map,unsigned long size,unsigned long start,unsigned int nr,unsigned long align_mask)145 bitmap_find_next_zero_area(unsigned long *map,
146 unsigned long size,
147 unsigned long start,
148 unsigned int nr,
149 unsigned long align_mask)
150 {
151 return bitmap_find_next_zero_area_off(map, size, start, nr,
152 align_mask, 0);
153 }
154
155 extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
156 unsigned long *dst, int nbits);
157 extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
158 unsigned long *dst, int nbits);
159 extern int bitmap_parselist(const char *buf, unsigned long *maskp,
160 int nmaskbits);
161 extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
162 unsigned long *dst, int nbits);
163 extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
164 const unsigned long *old, const unsigned long *new, unsigned int nbits);
165 extern int bitmap_bitremap(int oldbit,
166 const unsigned long *old, const unsigned long *new, int bits);
167 extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
168 const unsigned long *relmap, unsigned int bits);
169 extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
170 unsigned int sz, unsigned int nbits);
171 extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
172 extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
173 extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
174 #ifdef __BIG_ENDIAN
175 extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
176 #else
177 #define bitmap_copy_le bitmap_copy
178 #endif
179 extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits);
180 extern int bitmap_print_to_pagebuf(bool list, char *buf,
181 const unsigned long *maskp, int nmaskbits);
182
183 #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
184 #define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
185
186 /*
187 * The static inlines below do not handle constant nbits==0 correctly,
188 * so make such users (should any ever turn up) call the out-of-line
189 * versions.
190 */
191 #define small_const_nbits(nbits) \
192 (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG && (nbits) > 0)
193
bitmap_zero(unsigned long * dst,unsigned int nbits)194 static inline void bitmap_zero(unsigned long *dst, unsigned int nbits)
195 {
196 if (small_const_nbits(nbits))
197 *dst = 0UL;
198 else {
199 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
200 memset(dst, 0, len);
201 }
202 }
203
bitmap_fill(unsigned long * dst,unsigned int nbits)204 static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
205 {
206 unsigned int nlongs = BITS_TO_LONGS(nbits);
207 if (!small_const_nbits(nbits)) {
208 unsigned int len = (nlongs - 1) * sizeof(unsigned long);
209 memset(dst, 0xff, len);
210 }
211 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
212 }
213
bitmap_copy(unsigned long * dst,const unsigned long * src,unsigned int nbits)214 static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
215 unsigned int nbits)
216 {
217 if (small_const_nbits(nbits))
218 *dst = *src;
219 else {
220 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
221 memcpy(dst, src, len);
222 }
223 }
224
bitmap_and(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)225 static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
226 const unsigned long *src2, unsigned int nbits)
227 {
228 if (small_const_nbits(nbits))
229 return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0;
230 return __bitmap_and(dst, src1, src2, nbits);
231 }
232
bitmap_or(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)233 static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
234 const unsigned long *src2, unsigned int nbits)
235 {
236 if (small_const_nbits(nbits))
237 *dst = *src1 | *src2;
238 else
239 __bitmap_or(dst, src1, src2, nbits);
240 }
241
bitmap_xor(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)242 static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
243 const unsigned long *src2, unsigned int nbits)
244 {
245 if (small_const_nbits(nbits))
246 *dst = *src1 ^ *src2;
247 else
248 __bitmap_xor(dst, src1, src2, nbits);
249 }
250
bitmap_andnot(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)251 static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1,
252 const unsigned long *src2, unsigned int nbits)
253 {
254 if (small_const_nbits(nbits))
255 return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
256 return __bitmap_andnot(dst, src1, src2, nbits);
257 }
258
bitmap_complement(unsigned long * dst,const unsigned long * src,unsigned int nbits)259 static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
260 unsigned int nbits)
261 {
262 if (small_const_nbits(nbits))
263 *dst = ~(*src);
264 else
265 __bitmap_complement(dst, src, nbits);
266 }
267
bitmap_equal(const unsigned long * src1,const unsigned long * src2,unsigned int nbits)268 static inline int bitmap_equal(const unsigned long *src1,
269 const unsigned long *src2, unsigned int nbits)
270 {
271 if (small_const_nbits(nbits))
272 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
273 else
274 return __bitmap_equal(src1, src2, nbits);
275 }
276
bitmap_intersects(const unsigned long * src1,const unsigned long * src2,unsigned int nbits)277 static inline int bitmap_intersects(const unsigned long *src1,
278 const unsigned long *src2, unsigned int nbits)
279 {
280 if (small_const_nbits(nbits))
281 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
282 else
283 return __bitmap_intersects(src1, src2, nbits);
284 }
285
bitmap_subset(const unsigned long * src1,const unsigned long * src2,unsigned int nbits)286 static inline int bitmap_subset(const unsigned long *src1,
287 const unsigned long *src2, unsigned int nbits)
288 {
289 if (small_const_nbits(nbits))
290 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
291 else
292 return __bitmap_subset(src1, src2, nbits);
293 }
294
bitmap_empty(const unsigned long * src,unsigned nbits)295 static inline int bitmap_empty(const unsigned long *src, unsigned nbits)
296 {
297 if (small_const_nbits(nbits))
298 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
299
300 return find_first_bit(src, nbits) == nbits;
301 }
302
bitmap_full(const unsigned long * src,unsigned int nbits)303 static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
304 {
305 if (small_const_nbits(nbits))
306 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
307
308 return find_first_zero_bit(src, nbits) == nbits;
309 }
310
bitmap_weight(const unsigned long * src,unsigned int nbits)311 static __always_inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
312 {
313 if (small_const_nbits(nbits))
314 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
315 return __bitmap_weight(src, nbits);
316 }
317
bitmap_shift_right(unsigned long * dst,const unsigned long * src,unsigned int shift,unsigned int nbits)318 static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src,
319 unsigned int shift, unsigned int nbits)
320 {
321 if (small_const_nbits(nbits))
322 *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift;
323 else
324 __bitmap_shift_right(dst, src, shift, nbits);
325 }
326
bitmap_shift_left(unsigned long * dst,const unsigned long * src,unsigned int shift,unsigned int nbits)327 static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src,
328 unsigned int shift, unsigned int nbits)
329 {
330 if (small_const_nbits(nbits))
331 *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits);
332 else
333 __bitmap_shift_left(dst, src, shift, nbits);
334 }
335
bitmap_parse(const char * buf,unsigned int buflen,unsigned long * maskp,int nmaskbits)336 static inline int bitmap_parse(const char *buf, unsigned int buflen,
337 unsigned long *maskp, int nmaskbits)
338 {
339 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
340 }
341
342 #endif /* __ASSEMBLY__ */
343
344 #endif /* __LINUX_BITMAP_H */
345