Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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_shift_right(dst, src, n, nbits) *dst = *src >> n
46 * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
47 * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
48 * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
49 * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
50 * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz
51 * bitmap_scnprintf(buf, len, src, nbits) Print bitmap src to buf
52 * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
53 * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
54 * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf
55 * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from list
56 * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
57 * bitmap_release_region(bitmap, pos, order) Free specified bit region
58 * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
59 */
60
61/*
62 * Also the following operations in asm/bitops.h apply to bitmaps.
63 *
64 * set_bit(bit, addr) *addr |= bit
65 * clear_bit(bit, addr) *addr &= ~bit
66 * change_bit(bit, addr) *addr ^= bit
67 * test_bit(bit, addr) Is bit set in *addr?
68 * test_and_set_bit(bit, addr) Set bit and return old value
69 * test_and_clear_bit(bit, addr) Clear bit and return old value
70 * test_and_change_bit(bit, addr) Change bit and return old value
71 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
72 * find_first_bit(addr, nbits) Position first set bit in *addr
73 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
74 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
75 */
76
77/*
78 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
79 * to declare an array named 'name' of just enough unsigned longs to
80 * contain all bit positions from 0 to 'bits' - 1.
81 */
82
83/*
84 * lib/bitmap.c provides these functions:
85 */
86
87extern int __bitmap_empty(const unsigned long *bitmap, int bits);
88extern int __bitmap_full(const unsigned long *bitmap, int bits);
89extern int __bitmap_equal(const unsigned long *bitmap1,
90 const unsigned long *bitmap2, int bits);
91extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
92 int bits);
93extern void __bitmap_shift_right(unsigned long *dst,
94 const unsigned long *src, int shift, int bits);
95extern void __bitmap_shift_left(unsigned long *dst,
96 const unsigned long *src, int shift, int bits);
97extern void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
98 const unsigned long *bitmap2, int bits);
99extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
100 const unsigned long *bitmap2, int bits);
101extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
102 const unsigned long *bitmap2, int bits);
103extern void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
104 const unsigned long *bitmap2, int bits);
105extern int __bitmap_intersects(const unsigned long *bitmap1,
106 const unsigned long *bitmap2, int bits);
107extern int __bitmap_subset(const unsigned long *bitmap1,
108 const unsigned long *bitmap2, int bits);
109extern int __bitmap_weight(const unsigned long *bitmap, int bits);
110
111extern int bitmap_scnprintf(char *buf, unsigned int len,
112 const unsigned long *src, int nbits);
113extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
114 unsigned long *dst, int nbits);
115extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
116 unsigned long *dst, int nbits);
117extern int bitmap_scnlistprintf(char *buf, unsigned int len,
118 const unsigned long *src, int nbits);
119extern int bitmap_parselist(const char *buf, unsigned long *maskp,
120 int nmaskbits);
121extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
122 const unsigned long *old, const unsigned long *new, int bits);
123extern int bitmap_bitremap(int oldbit,
124 const unsigned long *old, const unsigned long *new, int bits);
125extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
126 const unsigned long *relmap, int bits);
127extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
128 int sz, int bits);
129extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
130extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
131extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
132
133#define BITMAP_LAST_WORD_MASK(nbits) \
134( \
135 ((nbits) % BITS_PER_LONG) ? \
136 (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
137)
138
139static inline void bitmap_zero(unsigned long *dst, int nbits)
140{
141 if (nbits <= BITS_PER_LONG)
142 *dst = 0UL;
143 else {
144 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
145 memset(dst, 0, len);
146 }
147}
148
149static inline void bitmap_fill(unsigned long *dst, int nbits)
150{
151 size_t nlongs = BITS_TO_LONGS(nbits);
152 if (nlongs > 1) {
153 int len = (nlongs - 1) * sizeof(unsigned long);
154 memset(dst, 0xff, len);
155 }
156 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
157}
158
159static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
160 int nbits)
161{
162 if (nbits <= BITS_PER_LONG)
163 *dst = *src;
164 else {
165 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
166 memcpy(dst, src, len);
167 }
168}
169
170static inline void bitmap_and(unsigned long *dst, const unsigned long *src1,
171 const unsigned long *src2, int nbits)
172{
173 if (nbits <= BITS_PER_LONG)
174 *dst = *src1 & *src2;
175 else
176 __bitmap_and(dst, src1, src2, nbits);
177}
178
179static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
180 const unsigned long *src2, int nbits)
181{
182 if (nbits <= BITS_PER_LONG)
183 *dst = *src1 | *src2;
184 else
185 __bitmap_or(dst, src1, src2, nbits);
186}
187
188static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
189 const unsigned long *src2, int nbits)
190{
191 if (nbits <= BITS_PER_LONG)
192 *dst = *src1 ^ *src2;
193 else
194 __bitmap_xor(dst, src1, src2, nbits);
195}
196
197static inline void bitmap_andnot(unsigned long *dst, const unsigned long *src1,
198 const unsigned long *src2, int nbits)
199{
200 if (nbits <= BITS_PER_LONG)
201 *dst = *src1 & ~(*src2);
202 else
203 __bitmap_andnot(dst, src1, src2, nbits);
204}
205
206static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
207 int nbits)
208{
209 if (nbits <= BITS_PER_LONG)
210 *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits);
211 else
212 __bitmap_complement(dst, src, nbits);
213}
214
215static inline int bitmap_equal(const unsigned long *src1,
216 const unsigned long *src2, int nbits)
217{
218 if (nbits <= BITS_PER_LONG)
219 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
220 else
221 return __bitmap_equal(src1, src2, nbits);
222}
223
224static inline int bitmap_intersects(const unsigned long *src1,
225 const unsigned long *src2, int nbits)
226{
227 if (nbits <= BITS_PER_LONG)
228 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
229 else
230 return __bitmap_intersects(src1, src2, nbits);
231}
232
233static inline int bitmap_subset(const unsigned long *src1,
234 const unsigned long *src2, int nbits)
235{
236 if (nbits <= BITS_PER_LONG)
237 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
238 else
239 return __bitmap_subset(src1, src2, nbits);
240}
241
242static inline int bitmap_empty(const unsigned long *src, int nbits)
243{
244 if (nbits <= BITS_PER_LONG)
245 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
246 else
247 return __bitmap_empty(src, nbits);
248}
249
250static inline int bitmap_full(const unsigned long *src, int nbits)
251{
252 if (nbits <= BITS_PER_LONG)
253 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
254 else
255 return __bitmap_full(src, nbits);
256}
257
258static inline int bitmap_weight(const unsigned long *src, int nbits)
259{
260 if (nbits <= BITS_PER_LONG)
261 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
262 return __bitmap_weight(src, nbits);
263}
264
265static inline void bitmap_shift_right(unsigned long *dst,
266 const unsigned long *src, int n, int nbits)
267{
268 if (nbits <= BITS_PER_LONG)
269 *dst = *src >> n;
270 else
271 __bitmap_shift_right(dst, src, n, nbits);
272}
273
274static inline void bitmap_shift_left(unsigned long *dst,
275 const unsigned long *src, int n, int nbits)
276{
277 if (nbits <= BITS_PER_LONG)
278 *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
279 else
280 __bitmap_shift_left(dst, src, n, nbits);
281}
282
283static inline int bitmap_parse(const char *buf, unsigned int buflen,
284 unsigned long *maskp, int nmaskbits)
285{
286 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
287}
288
289#endif /* __ASSEMBLY__ */
290
291#endif /* __LINUX_BITMAP_H */