diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-alpha/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-alpha/bitops.h')
-rw-r--r-- | include/asm-alpha/bitops.h | 507 |
1 files changed, 507 insertions, 0 deletions
diff --git a/include/asm-alpha/bitops.h b/include/asm-alpha/bitops.h new file mode 100644 index 000000000000..578ed3f1a607 --- /dev/null +++ b/include/asm-alpha/bitops.h | |||
@@ -0,0 +1,507 @@ | |||
1 | #ifndef _ALPHA_BITOPS_H | ||
2 | #define _ALPHA_BITOPS_H | ||
3 | |||
4 | #include <linux/config.h> | ||
5 | #include <asm/compiler.h> | ||
6 | |||
7 | /* | ||
8 | * Copyright 1994, Linus Torvalds. | ||
9 | */ | ||
10 | |||
11 | /* | ||
12 | * These have to be done with inline assembly: that way the bit-setting | ||
13 | * is guaranteed to be atomic. All bit operations return 0 if the bit | ||
14 | * was cleared before the operation and != 0 if it was not. | ||
15 | * | ||
16 | * To get proper branch prediction for the main line, we must branch | ||
17 | * forward to code at the end of this object's .text section, then | ||
18 | * branch back to restart the operation. | ||
19 | * | ||
20 | * bit 0 is the LSB of addr; bit 64 is the LSB of (addr+1). | ||
21 | */ | ||
22 | |||
23 | static inline void | ||
24 | set_bit(unsigned long nr, volatile void * addr) | ||
25 | { | ||
26 | unsigned long temp; | ||
27 | int *m = ((int *) addr) + (nr >> 5); | ||
28 | |||
29 | __asm__ __volatile__( | ||
30 | "1: ldl_l %0,%3\n" | ||
31 | " bis %0,%2,%0\n" | ||
32 | " stl_c %0,%1\n" | ||
33 | " beq %0,2f\n" | ||
34 | ".subsection 2\n" | ||
35 | "2: br 1b\n" | ||
36 | ".previous" | ||
37 | :"=&r" (temp), "=m" (*m) | ||
38 | :"Ir" (1UL << (nr & 31)), "m" (*m)); | ||
39 | } | ||
40 | |||
41 | /* | ||
42 | * WARNING: non atomic version. | ||
43 | */ | ||
44 | static inline void | ||
45 | __set_bit(unsigned long nr, volatile void * addr) | ||
46 | { | ||
47 | int *m = ((int *) addr) + (nr >> 5); | ||
48 | |||
49 | *m |= 1 << (nr & 31); | ||
50 | } | ||
51 | |||
52 | #define smp_mb__before_clear_bit() smp_mb() | ||
53 | #define smp_mb__after_clear_bit() smp_mb() | ||
54 | |||
55 | static inline void | ||
56 | clear_bit(unsigned long nr, volatile void * addr) | ||
57 | { | ||
58 | unsigned long temp; | ||
59 | int *m = ((int *) addr) + (nr >> 5); | ||
60 | |||
61 | __asm__ __volatile__( | ||
62 | "1: ldl_l %0,%3\n" | ||
63 | " bic %0,%2,%0\n" | ||
64 | " stl_c %0,%1\n" | ||
65 | " beq %0,2f\n" | ||
66 | ".subsection 2\n" | ||
67 | "2: br 1b\n" | ||
68 | ".previous" | ||
69 | :"=&r" (temp), "=m" (*m) | ||
70 | :"Ir" (1UL << (nr & 31)), "m" (*m)); | ||
71 | } | ||
72 | |||
73 | /* | ||
74 | * WARNING: non atomic version. | ||
75 | */ | ||
76 | static __inline__ void | ||
77 | __clear_bit(unsigned long nr, volatile void * addr) | ||
78 | { | ||
79 | int *m = ((int *) addr) + (nr >> 5); | ||
80 | |||
81 | *m &= ~(1 << (nr & 31)); | ||
82 | } | ||
83 | |||
84 | static inline void | ||
85 | change_bit(unsigned long nr, volatile void * addr) | ||
86 | { | ||
87 | unsigned long temp; | ||
88 | int *m = ((int *) addr) + (nr >> 5); | ||
89 | |||
90 | __asm__ __volatile__( | ||
91 | "1: ldl_l %0,%3\n" | ||
92 | " xor %0,%2,%0\n" | ||
93 | " stl_c %0,%1\n" | ||
94 | " beq %0,2f\n" | ||
95 | ".subsection 2\n" | ||
96 | "2: br 1b\n" | ||
97 | ".previous" | ||
98 | :"=&r" (temp), "=m" (*m) | ||
99 | :"Ir" (1UL << (nr & 31)), "m" (*m)); | ||
100 | } | ||
101 | |||
102 | /* | ||
103 | * WARNING: non atomic version. | ||
104 | */ | ||
105 | static __inline__ void | ||
106 | __change_bit(unsigned long nr, volatile void * addr) | ||
107 | { | ||
108 | int *m = ((int *) addr) + (nr >> 5); | ||
109 | |||
110 | *m ^= 1 << (nr & 31); | ||
111 | } | ||
112 | |||
113 | static inline int | ||
114 | test_and_set_bit(unsigned long nr, volatile void *addr) | ||
115 | { | ||
116 | unsigned long oldbit; | ||
117 | unsigned long temp; | ||
118 | int *m = ((int *) addr) + (nr >> 5); | ||
119 | |||
120 | __asm__ __volatile__( | ||
121 | "1: ldl_l %0,%4\n" | ||
122 | " and %0,%3,%2\n" | ||
123 | " bne %2,2f\n" | ||
124 | " xor %0,%3,%0\n" | ||
125 | " stl_c %0,%1\n" | ||
126 | " beq %0,3f\n" | ||
127 | "2:\n" | ||
128 | #ifdef CONFIG_SMP | ||
129 | " mb\n" | ||
130 | #endif | ||
131 | ".subsection 2\n" | ||
132 | "3: br 1b\n" | ||
133 | ".previous" | ||
134 | :"=&r" (temp), "=m" (*m), "=&r" (oldbit) | ||
135 | :"Ir" (1UL << (nr & 31)), "m" (*m) : "memory"); | ||
136 | |||
137 | return oldbit != 0; | ||
138 | } | ||
139 | |||
140 | /* | ||
141 | * WARNING: non atomic version. | ||
142 | */ | ||
143 | static inline int | ||
144 | __test_and_set_bit(unsigned long nr, volatile void * addr) | ||
145 | { | ||
146 | unsigned long mask = 1 << (nr & 0x1f); | ||
147 | int *m = ((int *) addr) + (nr >> 5); | ||
148 | int old = *m; | ||
149 | |||
150 | *m = old | mask; | ||
151 | return (old & mask) != 0; | ||
152 | } | ||
153 | |||
154 | static inline int | ||
155 | test_and_clear_bit(unsigned long nr, volatile void * addr) | ||
156 | { | ||
157 | unsigned long oldbit; | ||
158 | unsigned long temp; | ||
159 | int *m = ((int *) addr) + (nr >> 5); | ||
160 | |||
161 | __asm__ __volatile__( | ||
162 | "1: ldl_l %0,%4\n" | ||
163 | " and %0,%3,%2\n" | ||
164 | " beq %2,2f\n" | ||
165 | " xor %0,%3,%0\n" | ||
166 | " stl_c %0,%1\n" | ||
167 | " beq %0,3f\n" | ||
168 | "2:\n" | ||
169 | #ifdef CONFIG_SMP | ||
170 | " mb\n" | ||
171 | #endif | ||
172 | ".subsection 2\n" | ||
173 | "3: br 1b\n" | ||
174 | ".previous" | ||
175 | :"=&r" (temp), "=m" (*m), "=&r" (oldbit) | ||
176 | :"Ir" (1UL << (nr & 31)), "m" (*m) : "memory"); | ||
177 | |||
178 | return oldbit != 0; | ||
179 | } | ||
180 | |||
181 | /* | ||
182 | * WARNING: non atomic version. | ||
183 | */ | ||
184 | static inline int | ||
185 | __test_and_clear_bit(unsigned long nr, volatile void * addr) | ||
186 | { | ||
187 | unsigned long mask = 1 << (nr & 0x1f); | ||
188 | int *m = ((int *) addr) + (nr >> 5); | ||
189 | int old = *m; | ||
190 | |||
191 | *m = old & ~mask; | ||
192 | return (old & mask) != 0; | ||
193 | } | ||
194 | |||
195 | static inline int | ||
196 | test_and_change_bit(unsigned long nr, volatile void * addr) | ||
197 | { | ||
198 | unsigned long oldbit; | ||
199 | unsigned long temp; | ||
200 | int *m = ((int *) addr) + (nr >> 5); | ||
201 | |||
202 | __asm__ __volatile__( | ||
203 | "1: ldl_l %0,%4\n" | ||
204 | " and %0,%3,%2\n" | ||
205 | " xor %0,%3,%0\n" | ||
206 | " stl_c %0,%1\n" | ||
207 | " beq %0,3f\n" | ||
208 | #ifdef CONFIG_SMP | ||
209 | " mb\n" | ||
210 | #endif | ||
211 | ".subsection 2\n" | ||
212 | "3: br 1b\n" | ||
213 | ".previous" | ||
214 | :"=&r" (temp), "=m" (*m), "=&r" (oldbit) | ||
215 | :"Ir" (1UL << (nr & 31)), "m" (*m) : "memory"); | ||
216 | |||
217 | return oldbit != 0; | ||
218 | } | ||
219 | |||
220 | /* | ||
221 | * WARNING: non atomic version. | ||
222 | */ | ||
223 | static __inline__ int | ||
224 | __test_and_change_bit(unsigned long nr, volatile void * addr) | ||
225 | { | ||
226 | unsigned long mask = 1 << (nr & 0x1f); | ||
227 | int *m = ((int *) addr) + (nr >> 5); | ||
228 | int old = *m; | ||
229 | |||
230 | *m = old ^ mask; | ||
231 | return (old & mask) != 0; | ||
232 | } | ||
233 | |||
234 | static inline int | ||
235 | test_bit(int nr, const volatile void * addr) | ||
236 | { | ||
237 | return (1UL & (((const int *) addr)[nr >> 5] >> (nr & 31))) != 0UL; | ||
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 | * Do a binary search on the bits. Due to the nature of large | ||
245 | * constants on the alpha, it is worthwhile to split the search. | ||
246 | */ | ||
247 | static inline unsigned long ffz_b(unsigned long x) | ||
248 | { | ||
249 | unsigned long sum, x1, x2, x4; | ||
250 | |||
251 | x = ~x & -~x; /* set first 0 bit, clear others */ | ||
252 | x1 = x & 0xAA; | ||
253 | x2 = x & 0xCC; | ||
254 | x4 = x & 0xF0; | ||
255 | sum = x2 ? 2 : 0; | ||
256 | sum += (x4 != 0) * 4; | ||
257 | sum += (x1 != 0); | ||
258 | |||
259 | return sum; | ||
260 | } | ||
261 | |||
262 | static inline unsigned long ffz(unsigned long word) | ||
263 | { | ||
264 | #if defined(__alpha_cix__) && defined(__alpha_fix__) | ||
265 | /* Whee. EV67 can calculate it directly. */ | ||
266 | return __kernel_cttz(~word); | ||
267 | #else | ||
268 | unsigned long bits, qofs, bofs; | ||
269 | |||
270 | bits = __kernel_cmpbge(word, ~0UL); | ||
271 | qofs = ffz_b(bits); | ||
272 | bits = __kernel_extbl(word, qofs); | ||
273 | bofs = ffz_b(bits); | ||
274 | |||
275 | return qofs*8 + bofs; | ||
276 | #endif | ||
277 | } | ||
278 | |||
279 | /* | ||
280 | * __ffs = Find First set bit in word. Undefined if no set bit exists. | ||
281 | */ | ||
282 | static inline unsigned long __ffs(unsigned long word) | ||
283 | { | ||
284 | #if defined(__alpha_cix__) && defined(__alpha_fix__) | ||
285 | /* Whee. EV67 can calculate it directly. */ | ||
286 | return __kernel_cttz(word); | ||
287 | #else | ||
288 | unsigned long bits, qofs, bofs; | ||
289 | |||
290 | bits = __kernel_cmpbge(0, word); | ||
291 | qofs = ffz_b(bits); | ||
292 | bits = __kernel_extbl(word, qofs); | ||
293 | bofs = ffz_b(~bits); | ||
294 | |||
295 | return qofs*8 + bofs; | ||
296 | #endif | ||
297 | } | ||
298 | |||
299 | #ifdef __KERNEL__ | ||
300 | |||
301 | /* | ||
302 | * ffs: find first bit set. This is defined the same way as | ||
303 | * the libc and compiler builtin ffs routines, therefore | ||
304 | * differs in spirit from the above __ffs. | ||
305 | */ | ||
306 | |||
307 | static inline int ffs(int word) | ||
308 | { | ||
309 | int result = __ffs(word) + 1; | ||
310 | return word ? result : 0; | ||
311 | } | ||
312 | |||
313 | /* | ||
314 | * fls: find last bit set. | ||
315 | */ | ||
316 | #if defined(__alpha_cix__) && defined(__alpha_fix__) | ||
317 | static inline int fls(int word) | ||
318 | { | ||
319 | return 64 - __kernel_ctlz(word & 0xffffffff); | ||
320 | } | ||
321 | #else | ||
322 | #define fls generic_fls | ||
323 | #endif | ||
324 | |||
325 | /* Compute powers of two for the given integer. */ | ||
326 | static inline long floor_log2(unsigned long word) | ||
327 | { | ||
328 | #if defined(__alpha_cix__) && defined(__alpha_fix__) | ||
329 | return 63 - __kernel_ctlz(word); | ||
330 | #else | ||
331 | long bit; | ||
332 | for (bit = -1; word ; bit++) | ||
333 | word >>= 1; | ||
334 | return bit; | ||
335 | #endif | ||
336 | } | ||
337 | |||
338 | static inline long ceil_log2(unsigned long word) | ||
339 | { | ||
340 | long bit = floor_log2(word); | ||
341 | return bit + (word > (1UL << bit)); | ||
342 | } | ||
343 | |||
344 | /* | ||
345 | * hweightN: returns the hamming weight (i.e. the number | ||
346 | * of bits set) of a N-bit word | ||
347 | */ | ||
348 | |||
349 | #if defined(__alpha_cix__) && defined(__alpha_fix__) | ||
350 | /* Whee. EV67 can calculate it directly. */ | ||
351 | static inline unsigned long hweight64(unsigned long w) | ||
352 | { | ||
353 | return __kernel_ctpop(w); | ||
354 | } | ||
355 | |||
356 | #define hweight32(x) (unsigned int) hweight64((x) & 0xfffffffful) | ||
357 | #define hweight16(x) (unsigned int) hweight64((x) & 0xfffful) | ||
358 | #define hweight8(x) (unsigned int) hweight64((x) & 0xfful) | ||
359 | #else | ||
360 | static inline unsigned long hweight64(unsigned long w) | ||
361 | { | ||
362 | unsigned long result; | ||
363 | for (result = 0; w ; w >>= 1) | ||
364 | result += (w & 1); | ||
365 | return result; | ||
366 | } | ||
367 | |||
368 | #define hweight32(x) generic_hweight32(x) | ||
369 | #define hweight16(x) generic_hweight16(x) | ||
370 | #define hweight8(x) generic_hweight8(x) | ||
371 | #endif | ||
372 | |||
373 | #endif /* __KERNEL__ */ | ||
374 | |||
375 | /* | ||
376 | * Find next zero bit in a bitmap reasonably efficiently.. | ||
377 | */ | ||
378 | static inline unsigned long | ||
379 | find_next_zero_bit(const void *addr, unsigned long size, unsigned long offset) | ||
380 | { | ||
381 | const unsigned long *p = addr; | ||
382 | unsigned long result = offset & ~63UL; | ||
383 | unsigned long tmp; | ||
384 | |||
385 | p += offset >> 6; | ||
386 | if (offset >= size) | ||
387 | return size; | ||
388 | size -= result; | ||
389 | offset &= 63UL; | ||
390 | if (offset) { | ||
391 | tmp = *(p++); | ||
392 | tmp |= ~0UL >> (64-offset); | ||
393 | if (size < 64) | ||
394 | goto found_first; | ||
395 | if (~tmp) | ||
396 | goto found_middle; | ||
397 | size -= 64; | ||
398 | result += 64; | ||
399 | } | ||
400 | while (size & ~63UL) { | ||
401 | if (~(tmp = *(p++))) | ||
402 | goto found_middle; | ||
403 | result += 64; | ||
404 | size -= 64; | ||
405 | } | ||
406 | if (!size) | ||
407 | return result; | ||
408 | tmp = *p; | ||
409 | found_first: | ||
410 | tmp |= ~0UL << size; | ||
411 | if (tmp == ~0UL) /* Are any bits zero? */ | ||
412 | return result + size; /* Nope. */ | ||
413 | found_middle: | ||
414 | return result + ffz(tmp); | ||
415 | } | ||
416 | |||
417 | /* | ||
418 | * Find next one bit in a bitmap reasonably efficiently. | ||
419 | */ | ||
420 | static inline unsigned long | ||
421 | find_next_bit(const void * addr, unsigned long size, unsigned long offset) | ||
422 | { | ||
423 | const unsigned long *p = addr; | ||
424 | unsigned long result = offset & ~63UL; | ||
425 | unsigned long tmp; | ||
426 | |||
427 | p += offset >> 6; | ||
428 | if (offset >= size) | ||
429 | return size; | ||
430 | size -= result; | ||
431 | offset &= 63UL; | ||
432 | if (offset) { | ||
433 | tmp = *(p++); | ||
434 | tmp &= ~0UL << offset; | ||
435 | if (size < 64) | ||
436 | goto found_first; | ||
437 | if (tmp) | ||
438 | goto found_middle; | ||
439 | size -= 64; | ||
440 | result += 64; | ||
441 | } | ||
442 | while (size & ~63UL) { | ||
443 | if ((tmp = *(p++))) | ||
444 | goto found_middle; | ||
445 | result += 64; | ||
446 | size -= 64; | ||
447 | } | ||
448 | if (!size) | ||
449 | return result; | ||
450 | tmp = *p; | ||
451 | found_first: | ||
452 | tmp &= ~0UL >> (64 - size); | ||
453 | if (!tmp) | ||
454 | return result + size; | ||
455 | found_middle: | ||
456 | return result + __ffs(tmp); | ||
457 | } | ||
458 | |||
459 | /* | ||
460 | * The optimizer actually does good code for this case. | ||
461 | */ | ||
462 | #define find_first_zero_bit(addr, size) \ | ||
463 | find_next_zero_bit((addr), (size), 0) | ||
464 | #define find_first_bit(addr, size) \ | ||
465 | find_next_bit((addr), (size), 0) | ||
466 | |||
467 | #ifdef __KERNEL__ | ||
468 | |||
469 | /* | ||
470 | * Every architecture must define this function. It's the fastest | ||
471 | * way of searching a 140-bit bitmap where the first 100 bits are | ||
472 | * unlikely to be set. It's guaranteed that at least one of the 140 | ||
473 | * bits is set. | ||
474 | */ | ||
475 | static inline unsigned long | ||
476 | sched_find_first_bit(unsigned long b[3]) | ||
477 | { | ||
478 | unsigned long b0 = b[0], b1 = b[1], b2 = b[2]; | ||
479 | unsigned long ofs; | ||
480 | |||
481 | ofs = (b1 ? 64 : 128); | ||
482 | b1 = (b1 ? b1 : b2); | ||
483 | ofs = (b0 ? 0 : ofs); | ||
484 | b0 = (b0 ? b0 : b1); | ||
485 | |||
486 | return __ffs(b0) + ofs; | ||
487 | } | ||
488 | |||
489 | |||
490 | #define ext2_set_bit __test_and_set_bit | ||
491 | #define ext2_set_bit_atomic(l,n,a) test_and_set_bit(n,a) | ||
492 | #define ext2_clear_bit __test_and_clear_bit | ||
493 | #define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a) | ||
494 | #define ext2_test_bit test_bit | ||
495 | #define ext2_find_first_zero_bit find_first_zero_bit | ||
496 | #define ext2_find_next_zero_bit find_next_zero_bit | ||
497 | |||
498 | /* Bitmap functions for the minix filesystem. */ | ||
499 | #define minix_test_and_set_bit(nr,addr) __test_and_set_bit(nr,addr) | ||
500 | #define minix_set_bit(nr,addr) __set_bit(nr,addr) | ||
501 | #define minix_test_and_clear_bit(nr,addr) __test_and_clear_bit(nr,addr) | ||
502 | #define minix_test_bit(nr,addr) test_bit(nr,addr) | ||
503 | #define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size) | ||
504 | |||
505 | #endif /* __KERNEL__ */ | ||
506 | |||
507 | #endif /* _ALPHA_BITOPS_H */ | ||