Line data Source code
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 : * @offset: The bitnumber to start searching at
25 : * @size: The bitmap size in bits
26 : *
27 : * Returns the bit number for the next set bit
28 : * If no bits are set, returns @size.
29 : */
30 : static inline
31 1073 : unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
32 : unsigned long offset)
33 : {
34 1073 : if (small_const_nbits(size)) {
35 : unsigned long val;
36 :
37 0 : if (unlikely(offset >= size))
38 : return size;
39 :
40 0 : val = *addr & GENMASK(size - 1, offset);
41 0 : return val ? __ffs(val) : size;
42 : }
43 :
44 1073 : 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 : * @offset: The bitnumber to start searching at
54 : * @size: The bitmap size in bits
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 : * @offset: The bitnumber to start searching at
83 : * @size: The bitmap size in bits
84 : *
85 : * Returns the bit number of the next zero bit
86 : * If no bits are zero, returns @size.
87 : */
88 : static inline
89 1601 : unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
90 : unsigned long offset)
91 : {
92 1601 : if (small_const_nbits(size)) {
93 : unsigned long val;
94 :
95 83 : if (unlikely(offset >= size))
96 : return size;
97 :
98 83 : val = *addr | ~GENMASK(size - 1, offset);
99 165 : return val == ~0UL ? size : ffz(val);
100 : }
101 :
102 1518 : 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 0 : unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
117 : {
118 0 : if (small_const_nbits(size)) {
119 0 : unsigned long val = *addr & GENMASK(size - 1, 0);
120 :
121 0 : return val ? __ffs(val) : size;
122 : }
123 :
124 0 : 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
163 119 : unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size)
164 : {
165 119 : if (small_const_nbits(size)) {
166 0 : unsigned long val = *addr | ~GENMASK(size - 1, 0);
167 :
168 0 : return val == ~0UL ? size : ffz(val);
169 : }
170 :
171 120 : 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 0 : unsigned long find_last_bit(const unsigned long *addr, unsigned long size)
185 : {
186 0 : if (small_const_nbits(size)) {
187 0 : unsigned long val = *addr & GENMASK(size - 1, 0);
188 :
189 0 : return val ? __fls(val) : size;
190 : }
191 :
192 0 : 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_ */
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