1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef __LINUX_FIND_H_ |
3 | #define __LINUX_FIND_H_ |
4 | |
5 | #ifndef __LINUX_BITMAP_H |
6 | #error only <linux/bitmap.h> can be included directly |
7 | #endif |
8 | |
9 | #include <linux/bitops.h> |
10 | |
11 | extern unsigned long _find_next_bit(const unsigned long *addr1, |
12 | const unsigned long *addr2, unsigned long nbits, |
13 | unsigned long start, unsigned long invert, unsigned long le); |
14 | extern unsigned long _find_first_bit(const unsigned long *addr, unsigned long size); |
15 | extern unsigned long _find_first_and_bit(const unsigned long *addr1, |
16 | const unsigned long *addr2, unsigned long size); |
17 | extern unsigned long _find_first_zero_bit(const unsigned long *addr, unsigned long size); |
18 | extern unsigned long _find_last_bit(const unsigned long *addr, unsigned long size); |
19 | |
20 | #ifndef find_next_bit |
21 | /** |
22 | * find_next_bit - find the next set bit in a memory region |
23 | * @addr: The address to base the search on |
24 | * @size: The bitmap size in bits |
25 | * @offset: The bitnumber to start searching at |
26 | * |
27 | * Returns the bit number for the next set bit |
28 | * If no bits are set, returns @size. |
29 | */ |
30 | static inline |
31 | unsigned long find_next_bit(const unsigned long *addr, unsigned long size, |
32 | unsigned long offset) |
33 | { |
34 | if (small_const_nbits(size)) { |
35 | unsigned long val; |
36 | |
37 | if (unlikely(offset >= size)) |
38 | return size; |
39 | |
40 | val = *addr & GENMASK(size - 1, offset); |
41 | return val ? __ffs(val) : size; |
42 | } |
43 | |
44 | return _find_next_bit(addr, NULL, size, offset, 0UL, 0); |
45 | } |
46 | #endif |
47 | |
48 | #ifndef find_next_and_bit |
49 | /** |
50 | * find_next_and_bit - find the next set bit in both memory regions |
51 | * @addr1: The first address to base the search on |
52 | * @addr2: The second address to base the search on |
53 | * @size: The bitmap size in bits |
54 | * @offset: The bitnumber to start searching at |
55 | * |
56 | * Returns the bit number for the next set bit |
57 | * If no bits are set, returns @size. |
58 | */ |
59 | static inline |
60 | unsigned long find_next_and_bit(const unsigned long *addr1, |
61 | const unsigned long *addr2, unsigned long size, |
62 | unsigned long offset) |
63 | { |
64 | if (small_const_nbits(size)) { |
65 | unsigned long val; |
66 | |
67 | if (unlikely(offset >= size)) |
68 | return size; |
69 | |
70 | val = *addr1 & *addr2 & GENMASK(size - 1, offset); |
71 | return val ? __ffs(val) : size; |
72 | } |
73 | |
74 | return _find_next_bit(addr1, addr2, size, offset, 0UL, 0); |
75 | } |
76 | #endif |
77 | |
78 | #ifndef find_next_zero_bit |
79 | /** |
80 | * find_next_zero_bit - find the next cleared bit in a memory region |
81 | * @addr: The address to base the search on |
82 | * @size: The bitmap size in bits |
83 | * @offset: The bitnumber to start searching at |
84 | * |
85 | * Returns the bit number of the next zero bit |
86 | * If no bits are zero, returns @size. |
87 | */ |
88 | static inline |
89 | unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size, |
90 | unsigned long offset) |
91 | { |
92 | if (small_const_nbits(size)) { |
93 | unsigned long val; |
94 | |
95 | if (unlikely(offset >= size)) |
96 | return size; |
97 | |
98 | val = *addr | ~GENMASK(size - 1, offset); |
99 | return val == ~0UL ? size : ffz(val); |
100 | } |
101 | |
102 | return _find_next_bit(addr, NULL, size, offset, ~0UL, 0); |
103 | } |
104 | #endif |
105 | |
106 | #ifndef find_first_bit |
107 | /** |
108 | * find_first_bit - find the first set bit in a memory region |
109 | * @addr: The address to start the search at |
110 | * @size: The maximum number of bits to search |
111 | * |
112 | * Returns the bit number of the first set bit. |
113 | * If no bits are set, returns @size. |
114 | */ |
115 | static inline |
116 | unsigned long find_first_bit(const unsigned long *addr, unsigned long size) |
117 | { |
118 | if (small_const_nbits(size)) { |
119 | unsigned long val = *addr & GENMASK(size - 1, 0); |
120 | |
121 | return val ? __ffs(val) : size; |
122 | } |
123 | |
124 | return _find_first_bit(addr, size); |
125 | } |
126 | #endif |
127 | |
128 | #ifndef find_first_and_bit |
129 | /** |
130 | * find_first_and_bit - find the first set bit in both memory regions |
131 | * @addr1: The first address to base the search on |
132 | * @addr2: The second address to base the search on |
133 | * @size: The bitmap size in bits |
134 | * |
135 | * Returns the bit number for the next set bit |
136 | * If no bits are set, returns @size. |
137 | */ |
138 | static inline |
139 | unsigned long find_first_and_bit(const unsigned long *addr1, |
140 | const unsigned long *addr2, |
141 | unsigned long size) |
142 | { |
143 | if (small_const_nbits(size)) { |
144 | unsigned long val = *addr1 & *addr2 & GENMASK(size - 1, 0); |
145 | |
146 | return val ? __ffs(val) : size; |
147 | } |
148 | |
149 | return _find_first_and_bit(addr1, addr2, size); |
150 | } |
151 | #endif |
152 | |
153 | #ifndef find_first_zero_bit |
154 | /** |
155 | * find_first_zero_bit - find the first cleared bit in a memory region |
156 | * @addr: The address to start the search at |
157 | * @size: The maximum number of bits to search |
158 | * |
159 | * Returns the bit number of the first cleared bit. |
160 | * If no bits are zero, returns @size. |
161 | */ |
162 | static inline |
163 | unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size) |
164 | { |
165 | if (small_const_nbits(size)) { |
166 | unsigned long val = *addr | ~GENMASK(size - 1, 0); |
167 | |
168 | return val == ~0UL ? size : ffz(val); |
169 | } |
170 | |
171 | return _find_first_zero_bit(addr, size); |
172 | } |
173 | #endif |
174 | |
175 | #ifndef find_last_bit |
176 | /** |
177 | * find_last_bit - find the last set bit in a memory region |
178 | * @addr: The address to start the search at |
179 | * @size: The number of bits to search |
180 | * |
181 | * Returns the bit number of the last set bit, or size. |
182 | */ |
183 | static inline |
184 | unsigned long find_last_bit(const unsigned long *addr, unsigned long size) |
185 | { |
186 | if (small_const_nbits(size)) { |
187 | unsigned long val = *addr & GENMASK(size - 1, 0); |
188 | |
189 | return val ? __fls(val) : size; |
190 | } |
191 | |
192 | return _find_last_bit(addr, size); |
193 | } |
194 | #endif |
195 | |
196 | /** |
197 | * find_next_clump8 - find next 8-bit clump with set bits in a memory region |
198 | * @clump: location to store copy of found clump |
199 | * @addr: address to base the search on |
200 | * @size: bitmap size in number of bits |
201 | * @offset: bit offset at which to start searching |
202 | * |
203 | * Returns the bit offset for the next set clump; the found clump value is |
204 | * copied to the location pointed by @clump. If no bits are set, returns @size. |
205 | */ |
206 | extern unsigned long find_next_clump8(unsigned long *clump, |
207 | const unsigned long *addr, |
208 | unsigned long size, unsigned long offset); |
209 | |
210 | #define find_first_clump8(clump, bits, size) \ |
211 | find_next_clump8((clump), (bits), (size), 0) |
212 | |
213 | #if defined(__LITTLE_ENDIAN) |
214 | |
215 | static inline unsigned long find_next_zero_bit_le(const void *addr, |
216 | unsigned long size, unsigned long offset) |
217 | { |
218 | return find_next_zero_bit(addr, size, offset); |
219 | } |
220 | |
221 | static inline unsigned long find_next_bit_le(const void *addr, |
222 | unsigned long size, unsigned long offset) |
223 | { |
224 | return find_next_bit(addr, size, offset); |
225 | } |
226 | |
227 | static inline unsigned long find_first_zero_bit_le(const void *addr, |
228 | unsigned long size) |
229 | { |
230 | return find_first_zero_bit(addr, size); |
231 | } |
232 | |
233 | #elif defined(__BIG_ENDIAN) |
234 | |
235 | #ifndef find_next_zero_bit_le |
236 | static inline |
237 | unsigned long find_next_zero_bit_le(const void *addr, unsigned |
238 | long size, unsigned long offset) |
239 | { |
240 | if (small_const_nbits(size)) { |
241 | unsigned long val = *(const unsigned long *)addr; |
242 | |
243 | if (unlikely(offset >= size)) |
244 | return size; |
245 | |
246 | val = swab(val) | ~GENMASK(size - 1, offset); |
247 | return val == ~0UL ? size : ffz(val); |
248 | } |
249 | |
250 | return _find_next_bit(addr, NULL, size, offset, ~0UL, 1); |
251 | } |
252 | #endif |
253 | |
254 | #ifndef find_next_bit_le |
255 | static inline |
256 | unsigned long find_next_bit_le(const void *addr, unsigned |
257 | long size, unsigned long offset) |
258 | { |
259 | if (small_const_nbits(size)) { |
260 | unsigned long val = *(const unsigned long *)addr; |
261 | |
262 | if (unlikely(offset >= size)) |
263 | return size; |
264 | |
265 | val = swab(val) & GENMASK(size - 1, offset); |
266 | return val ? __ffs(val) : size; |
267 | } |
268 | |
269 | return _find_next_bit(addr, NULL, size, offset, 0UL, 1); |
270 | } |
271 | #endif |
272 | |
273 | #ifndef find_first_zero_bit_le |
274 | #define find_first_zero_bit_le(addr, size) \ |
275 | find_next_zero_bit_le((addr), (size), 0) |
276 | #endif |
277 | |
278 | #else |
279 | #error "Please fix <asm/byteorder.h>" |
280 | #endif |
281 | |
282 | #define for_each_set_bit(bit, addr, size) \ |
283 | for ((bit) = find_next_bit((addr), (size), 0); \ |
284 | (bit) < (size); \ |
285 | (bit) = find_next_bit((addr), (size), (bit) + 1)) |
286 | |
287 | /* same as for_each_set_bit() but use bit as value to start with */ |
288 | #define for_each_set_bit_from(bit, addr, size) \ |
289 | for ((bit) = find_next_bit((addr), (size), (bit)); \ |
290 | (bit) < (size); \ |
291 | (bit) = find_next_bit((addr), (size), (bit) + 1)) |
292 | |
293 | #define for_each_clear_bit(bit, addr, size) \ |
294 | for ((bit) = find_next_zero_bit((addr), (size), 0); \ |
295 | (bit) < (size); \ |
296 | (bit) = find_next_zero_bit((addr), (size), (bit) + 1)) |
297 | |
298 | /* same as for_each_clear_bit() but use bit as value to start with */ |
299 | #define for_each_clear_bit_from(bit, addr, size) \ |
300 | for ((bit) = find_next_zero_bit((addr), (size), (bit)); \ |
301 | (bit) < (size); \ |
302 | (bit) = find_next_zero_bit((addr), (size), (bit) + 1)) |
303 | |
304 | /** |
305 | * for_each_set_bitrange - iterate over all set bit ranges [b; e) |
306 | * @b: bit offset of start of current bitrange (first set bit) |
307 | * @e: bit offset of end of current bitrange (first unset bit) |
308 | * @addr: bitmap address to base the search on |
309 | * @size: bitmap size in number of bits |
310 | */ |
311 | #define for_each_set_bitrange(b, e, addr, size) \ |
312 | for ((b) = find_next_bit((addr), (size), 0), \ |
313 | (e) = find_next_zero_bit((addr), (size), (b) + 1); \ |
314 | (b) < (size); \ |
315 | (b) = find_next_bit((addr), (size), (e) + 1), \ |
316 | (e) = find_next_zero_bit((addr), (size), (b) + 1)) |
317 | |
318 | /** |
319 | * for_each_set_bitrange_from - iterate over all set bit ranges [b; e) |
320 | * @b: bit offset of start of current bitrange (first set bit); must be initialized |
321 | * @e: bit offset of end of current bitrange (first unset bit) |
322 | * @addr: bitmap address to base the search on |
323 | * @size: bitmap size in number of bits |
324 | */ |
325 | #define for_each_set_bitrange_from(b, e, addr, size) \ |
326 | for ((b) = find_next_bit((addr), (size), (b)), \ |
327 | (e) = find_next_zero_bit((addr), (size), (b) + 1); \ |
328 | (b) < (size); \ |
329 | (b) = find_next_bit((addr), (size), (e) + 1), \ |
330 | (e) = find_next_zero_bit((addr), (size), (b) + 1)) |
331 | |
332 | /** |
333 | * for_each_clear_bitrange - iterate over all unset bit ranges [b; e) |
334 | * @b: bit offset of start of current bitrange (first unset bit) |
335 | * @e: bit offset of end of current bitrange (first set bit) |
336 | * @addr: bitmap address to base the search on |
337 | * @size: bitmap size in number of bits |
338 | */ |
339 | #define for_each_clear_bitrange(b, e, addr, size) \ |
340 | for ((b) = find_next_zero_bit((addr), (size), 0), \ |
341 | (e) = find_next_bit((addr), (size), (b) + 1); \ |
342 | (b) < (size); \ |
343 | (b) = find_next_zero_bit((addr), (size), (e) + 1), \ |
344 | (e) = find_next_bit((addr), (size), (b) + 1)) |
345 | |
346 | /** |
347 | * for_each_clear_bitrange_from - iterate over all unset bit ranges [b; e) |
348 | * @b: bit offset of start of current bitrange (first set bit); must be initialized |
349 | * @e: bit offset of end of current bitrange (first unset bit) |
350 | * @addr: bitmap address to base the search on |
351 | * @size: bitmap size in number of bits |
352 | */ |
353 | #define for_each_clear_bitrange_from(b, e, addr, size) \ |
354 | for ((b) = find_next_zero_bit((addr), (size), (b)), \ |
355 | (e) = find_next_bit((addr), (size), (b) + 1); \ |
356 | (b) < (size); \ |
357 | (b) = find_next_zero_bit((addr), (size), (e) + 1), \ |
358 | (e) = find_next_bit((addr), (size), (b) + 1)) |
359 | |
360 | /** |
361 | * for_each_set_clump8 - iterate over bitmap for each 8-bit clump with set bits |
362 | * @start: bit offset to start search and to store the current iteration offset |
363 | * @clump: location to store copy of current 8-bit clump |
364 | * @bits: bitmap address to base the search on |
365 | * @size: bitmap size in number of bits |
366 | */ |
367 | #define for_each_set_clump8(start, clump, bits, size) \ |
368 | for ((start) = find_first_clump8(&(clump), (bits), (size)); \ |
369 | (start) < (size); \ |
370 | (start) = find_next_clump8(&(clump), (bits), (size), (start) + 8)) |
371 | |
372 | #endif /*__LINUX_FIND_H_ */ |
373 | |