diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-arm26/bitops.h |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-arm26/bitops.h')
-rw-r--r-- | include/asm-arm26/bitops.h | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/include/asm-arm26/bitops.h b/include/asm-arm26/bitops.h new file mode 100644 index 000000000000..7d062fb2e343 --- /dev/null +++ b/include/asm-arm26/bitops.h | |||
@@ -0,0 +1,332 @@ | |||
1 | /* | ||
2 | * Copyright 1995, Russell King. | ||
3 | * | ||
4 | * Based on the arm32 version by RMK (and others). Their copyrights apply to | ||
5 | * Those parts. | ||
6 | * Modified for arm26 by Ian Molton on 25/11/04 | ||
7 | * | ||
8 | * bit 0 is the LSB of an "unsigned long" quantity. | ||
9 | * | ||
10 | * Please note that the code in this file should never be included | ||
11 | * from user space. Many of these are not implemented in assembler | ||
12 | * since they would be too costly. Also, they require privileged | ||
13 | * instructions (which are not available from user mode) to ensure | ||
14 | * that they are atomic. | ||
15 | */ | ||
16 | |||
17 | #ifndef __ASM_ARM_BITOPS_H | ||
18 | #define __ASM_ARM_BITOPS_H | ||
19 | |||
20 | #ifdef __KERNEL__ | ||
21 | |||
22 | #include <linux/compiler.h> | ||
23 | #include <asm/system.h> | ||
24 | |||
25 | #define smp_mb__before_clear_bit() do { } while (0) | ||
26 | #define smp_mb__after_clear_bit() do { } while (0) | ||
27 | |||
28 | /* | ||
29 | * These functions are the basis of our bit ops. | ||
30 | * | ||
31 | * First, the atomic bitops. These use native endian. | ||
32 | */ | ||
33 | static inline void ____atomic_set_bit(unsigned int bit, volatile unsigned long *p) | ||
34 | { | ||
35 | unsigned long flags; | ||
36 | unsigned long mask = 1UL << (bit & 31); | ||
37 | |||
38 | p += bit >> 5; | ||
39 | |||
40 | local_irq_save(flags); | ||
41 | *p |= mask; | ||
42 | local_irq_restore(flags); | ||
43 | } | ||
44 | |||
45 | static inline void ____atomic_clear_bit(unsigned int bit, volatile unsigned long *p) | ||
46 | { | ||
47 | unsigned long flags; | ||
48 | unsigned long mask = 1UL << (bit & 31); | ||
49 | |||
50 | p += bit >> 5; | ||
51 | |||
52 | local_irq_save(flags); | ||
53 | *p &= ~mask; | ||
54 | local_irq_restore(flags); | ||
55 | } | ||
56 | |||
57 | static inline void ____atomic_change_bit(unsigned int bit, volatile unsigned long *p) | ||
58 | { | ||
59 | unsigned long flags; | ||
60 | unsigned long mask = 1UL << (bit & 31); | ||
61 | |||
62 | p += bit >> 5; | ||
63 | |||
64 | local_irq_save(flags); | ||
65 | *p ^= mask; | ||
66 | local_irq_restore(flags); | ||
67 | } | ||
68 | |||
69 | static inline int | ||
70 | ____atomic_test_and_set_bit(unsigned int bit, volatile unsigned long *p) | ||
71 | { | ||
72 | unsigned long flags; | ||
73 | unsigned int res; | ||
74 | unsigned long mask = 1UL << (bit & 31); | ||
75 | |||
76 | p += bit >> 5; | ||
77 | |||
78 | local_irq_save(flags); | ||
79 | res = *p; | ||
80 | *p = res | mask; | ||
81 | local_irq_restore(flags); | ||
82 | |||
83 | return res & mask; | ||
84 | } | ||
85 | |||
86 | static inline int | ||
87 | ____atomic_test_and_clear_bit(unsigned int bit, volatile unsigned long *p) | ||
88 | { | ||
89 | unsigned long flags; | ||
90 | unsigned int res; | ||
91 | unsigned long mask = 1UL << (bit & 31); | ||
92 | |||
93 | p += bit >> 5; | ||
94 | |||
95 | local_irq_save(flags); | ||
96 | res = *p; | ||
97 | *p = res & ~mask; | ||
98 | local_irq_restore(flags); | ||
99 | |||
100 | return res & mask; | ||
101 | } | ||
102 | |||
103 | static inline int | ||
104 | ____atomic_test_and_change_bit(unsigned int bit, volatile unsigned long *p) | ||
105 | { | ||
106 | unsigned long flags; | ||
107 | unsigned int res; | ||
108 | unsigned long mask = 1UL << (bit & 31); | ||
109 | |||
110 | p += bit >> 5; | ||
111 | |||
112 | local_irq_save(flags); | ||
113 | res = *p; | ||
114 | *p = res ^ mask; | ||
115 | local_irq_restore(flags); | ||
116 | |||
117 | return res & mask; | ||
118 | } | ||
119 | |||
120 | /* | ||
121 | * Now the non-atomic variants. We let the compiler handle all | ||
122 | * optimisations for these. These are all _native_ endian. | ||
123 | */ | ||
124 | static inline void __set_bit(int nr, volatile unsigned long *p) | ||
125 | { | ||
126 | p[nr >> 5] |= (1UL << (nr & 31)); | ||
127 | } | ||
128 | |||
129 | static inline void __clear_bit(int nr, volatile unsigned long *p) | ||
130 | { | ||
131 | p[nr >> 5] &= ~(1UL << (nr & 31)); | ||
132 | } | ||
133 | |||
134 | static inline void __change_bit(int nr, volatile unsigned long *p) | ||
135 | { | ||
136 | p[nr >> 5] ^= (1UL << (nr & 31)); | ||
137 | } | ||
138 | |||
139 | static inline int __test_and_set_bit(int nr, volatile unsigned long *p) | ||
140 | { | ||
141 | unsigned long oldval, mask = 1UL << (nr & 31); | ||
142 | |||
143 | p += nr >> 5; | ||
144 | |||
145 | oldval = *p; | ||
146 | *p = oldval | mask; | ||
147 | return oldval & mask; | ||
148 | } | ||
149 | |||
150 | static inline int __test_and_clear_bit(int nr, volatile unsigned long *p) | ||
151 | { | ||
152 | unsigned long oldval, mask = 1UL << (nr & 31); | ||
153 | |||
154 | p += nr >> 5; | ||
155 | |||
156 | oldval = *p; | ||
157 | *p = oldval & ~mask; | ||
158 | return oldval & mask; | ||
159 | } | ||
160 | |||
161 | static inline int __test_and_change_bit(int nr, volatile unsigned long *p) | ||
162 | { | ||
163 | unsigned long oldval, mask = 1UL << (nr & 31); | ||
164 | |||
165 | p += nr >> 5; | ||
166 | |||
167 | oldval = *p; | ||
168 | *p = oldval ^ mask; | ||
169 | return oldval & mask; | ||
170 | } | ||
171 | |||
172 | /* | ||
173 | * This routine doesn't need to be atomic. | ||
174 | */ | ||
175 | static inline int __test_bit(int nr, const volatile unsigned long * p) | ||
176 | { | ||
177 | return (p[nr >> 5] >> (nr & 31)) & 1UL; | ||
178 | } | ||
179 | |||
180 | /* | ||
181 | * Little endian assembly bitops. nr = 0 -> byte 0 bit 0. | ||
182 | */ | ||
183 | extern void _set_bit_le(int nr, volatile unsigned long * p); | ||
184 | extern void _clear_bit_le(int nr, volatile unsigned long * p); | ||
185 | extern void _change_bit_le(int nr, volatile unsigned long * p); | ||
186 | extern int _test_and_set_bit_le(int nr, volatile unsigned long * p); | ||
187 | extern int _test_and_clear_bit_le(int nr, volatile unsigned long * p); | ||
188 | extern int _test_and_change_bit_le(int nr, volatile unsigned long * p); | ||
189 | extern int _find_first_zero_bit_le(void * p, unsigned size); | ||
190 | extern int _find_next_zero_bit_le(void * p, int size, int offset); | ||
191 | extern int _find_first_bit_le(const unsigned long *p, unsigned size); | ||
192 | extern int _find_next_bit_le(const unsigned long *p, int size, int offset); | ||
193 | |||
194 | /* | ||
195 | * The __* form of bitops are non-atomic and may be reordered. | ||
196 | */ | ||
197 | #define ATOMIC_BITOP_LE(name,nr,p) \ | ||
198 | (__builtin_constant_p(nr) ? \ | ||
199 | ____atomic_##name(nr, p) : \ | ||
200 | _##name##_le(nr,p)) | ||
201 | |||
202 | #define NONATOMIC_BITOP(name,nr,p) \ | ||
203 | (____nonatomic_##name(nr, p)) | ||
204 | |||
205 | /* | ||
206 | * These are the little endian, atomic definitions. | ||
207 | */ | ||
208 | #define set_bit(nr,p) ATOMIC_BITOP_LE(set_bit,nr,p) | ||
209 | #define clear_bit(nr,p) ATOMIC_BITOP_LE(clear_bit,nr,p) | ||
210 | #define change_bit(nr,p) ATOMIC_BITOP_LE(change_bit,nr,p) | ||
211 | #define test_and_set_bit(nr,p) ATOMIC_BITOP_LE(test_and_set_bit,nr,p) | ||
212 | #define test_and_clear_bit(nr,p) ATOMIC_BITOP_LE(test_and_clear_bit,nr,p) | ||
213 | #define test_and_change_bit(nr,p) ATOMIC_BITOP_LE(test_and_change_bit,nr,p) | ||
214 | #define test_bit(nr,p) __test_bit(nr,p) | ||
215 | #define find_first_zero_bit(p,sz) _find_first_zero_bit_le(p,sz) | ||
216 | #define find_next_zero_bit(p,sz,off) _find_next_zero_bit_le(p,sz,off) | ||
217 | #define find_first_bit(p,sz) _find_first_bit_le(p,sz) | ||
218 | #define find_next_bit(p,sz,off) _find_next_bit_le(p,sz,off) | ||
219 | |||
220 | #define WORD_BITOFF_TO_LE(x) ((x)) | ||
221 | |||
222 | /* | ||
223 | * ffz = Find First Zero in word. Undefined if no zero exists, | ||
224 | * so code should check against ~0UL first.. | ||
225 | */ | ||
226 | static inline unsigned long ffz(unsigned long word) | ||
227 | { | ||
228 | int k; | ||
229 | |||
230 | word = ~word; | ||
231 | k = 31; | ||
232 | if (word & 0x0000ffff) { k -= 16; word <<= 16; } | ||
233 | if (word & 0x00ff0000) { k -= 8; word <<= 8; } | ||
234 | if (word & 0x0f000000) { k -= 4; word <<= 4; } | ||
235 | if (word & 0x30000000) { k -= 2; word <<= 2; } | ||
236 | if (word & 0x40000000) { k -= 1; } | ||
237 | return k; | ||
238 | } | ||
239 | |||
240 | /* | ||
241 | * ffz = Find First Zero in word. Undefined if no zero exists, | ||
242 | * so code should check against ~0UL first.. | ||
243 | */ | ||
244 | static inline unsigned long __ffs(unsigned long word) | ||
245 | { | ||
246 | int k; | ||
247 | |||
248 | k = 31; | ||
249 | if (word & 0x0000ffff) { k -= 16; word <<= 16; } | ||
250 | if (word & 0x00ff0000) { k -= 8; word <<= 8; } | ||
251 | if (word & 0x0f000000) { k -= 4; word <<= 4; } | ||
252 | if (word & 0x30000000) { k -= 2; word <<= 2; } | ||
253 | if (word & 0x40000000) { k -= 1; } | ||
254 | return k; | ||
255 | } | ||
256 | |||
257 | /* | ||
258 | * fls: find last bit set. | ||
259 | */ | ||
260 | |||
261 | #define fls(x) generic_fls(x) | ||
262 | |||
263 | /* | ||
264 | * ffs: find first bit set. This is defined the same way as | ||
265 | * the libc and compiler builtin ffs routines, therefore | ||
266 | * differs in spirit from the above ffz (man ffs). | ||
267 | */ | ||
268 | |||
269 | #define ffs(x) generic_ffs(x) | ||
270 | |||
271 | /* | ||
272 | * Find first bit set in a 168-bit bitmap, where the first | ||
273 | * 128 bits are unlikely to be set. | ||
274 | */ | ||
275 | static inline int sched_find_first_bit(unsigned long *b) | ||
276 | { | ||
277 | unsigned long v; | ||
278 | unsigned int off; | ||
279 | |||
280 | for (off = 0; v = b[off], off < 4; off++) { | ||
281 | if (unlikely(v)) | ||
282 | break; | ||
283 | } | ||
284 | return __ffs(v) + off * 32; | ||
285 | } | ||
286 | |||
287 | /* | ||
288 | * hweightN: returns the hamming weight (i.e. the number | ||
289 | * of bits set) of a N-bit word | ||
290 | */ | ||
291 | |||
292 | #define hweight32(x) generic_hweight32(x) | ||
293 | #define hweight16(x) generic_hweight16(x) | ||
294 | #define hweight8(x) generic_hweight8(x) | ||
295 | |||
296 | /* | ||
297 | * Ext2 is defined to use little-endian byte ordering. | ||
298 | * These do not need to be atomic. | ||
299 | */ | ||
300 | #define ext2_set_bit(nr,p) \ | ||
301 | __test_and_set_bit(WORD_BITOFF_TO_LE(nr), (unsigned long *)(p)) | ||
302 | #define ext2_set_bit_atomic(lock,nr,p) \ | ||
303 | test_and_set_bit(WORD_BITOFF_TO_LE(nr), (unsigned long *)(p)) | ||
304 | #define ext2_clear_bit(nr,p) \ | ||
305 | __test_and_clear_bit(WORD_BITOFF_TO_LE(nr), (unsigned long *)(p)) | ||
306 | #define ext2_clear_bit_atomic(lock,nr,p) \ | ||
307 | test_and_clear_bit(WORD_BITOFF_TO_LE(nr), (unsigned long *)(p)) | ||
308 | #define ext2_test_bit(nr,p) \ | ||
309 | __test_bit(WORD_BITOFF_TO_LE(nr), (unsigned long *)(p)) | ||
310 | #define ext2_find_first_zero_bit(p,sz) \ | ||
311 | _find_first_zero_bit_le(p,sz) | ||
312 | #define ext2_find_next_zero_bit(p,sz,off) \ | ||
313 | _find_next_zero_bit_le(p,sz,off) | ||
314 | |||
315 | /* | ||
316 | * Minix is defined to use little-endian byte ordering. | ||
317 | * These do not need to be atomic. | ||
318 | */ | ||
319 | #define minix_set_bit(nr,p) \ | ||
320 | __set_bit(WORD_BITOFF_TO_LE(nr), (unsigned long *)(p)) | ||
321 | #define minix_test_bit(nr,p) \ | ||
322 | __test_bit(WORD_BITOFF_TO_LE(nr), (unsigned long *)(p)) | ||
323 | #define minix_test_and_set_bit(nr,p) \ | ||
324 | __test_and_set_bit(WORD_BITOFF_TO_LE(nr), (unsigned long *)(p)) | ||
325 | #define minix_test_and_clear_bit(nr,p) \ | ||
326 | __test_and_clear_bit(WORD_BITOFF_TO_LE(nr), (unsigned long *)(p)) | ||
327 | #define minix_find_first_zero_bit(p,sz) \ | ||
328 | _find_first_zero_bit_le(p,sz) | ||
329 | |||
330 | #endif /* __KERNEL__ */ | ||
331 | |||
332 | #endif /* _ARM_BITOPS_H */ | ||