Home Home > GIT Browse
summaryrefslogtreecommitdiff
blob: c9d69c99e47007f227f235cba97dd1921ecf6990 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
#ifndef _ALPHA_BITOPS_H
#define _ALPHA_BITOPS_H

#include <linux/config.h>
#include <asm/compiler.h>

/*
 * Copyright 1994, Linus Torvalds.
 */

/*
 * These have to be done with inline assembly: that way the bit-setting
 * is guaranteed to be atomic. All bit operations return 0 if the bit
 * was cleared before the operation and != 0 if it was not.
 *
 * To get proper branch prediction for the main line, we must branch
 * forward to code at the end of this object's .text section, then
 * branch back to restart the operation.
 *
 * bit 0 is the LSB of addr; bit 64 is the LSB of (addr+1).
 */

static inline void
set_bit(unsigned long nr, volatile void * addr)
{
	unsigned long temp;
	int *m = ((int *) addr) + (nr >> 5);

	__asm__ __volatile__(
	"1:	ldl_l %0,%3\n"
	"	bis %0,%2,%0\n"
	"	stl_c %0,%1\n"
	"	beq %0,2f\n"
	".subsection 2\n"
	"2:	br 1b\n"
	".previous"
	:"=&r" (temp), "=m" (*m)
	:"Ir" (1UL << (nr & 31)), "m" (*m));
}

/*
 * WARNING: non atomic version.
 */
static inline void
__set_bit(unsigned long nr, volatile void * addr)
{
	int *m = ((int *) addr) + (nr >> 5);

	*m |= 1 << (nr & 31);
}

#define smp_mb__before_clear_bit()	smp_mb()
#define smp_mb__after_clear_bit()	smp_mb()

static inline void
clear_bit(unsigned long nr, volatile void * addr)
{
	unsigned long temp;
	int *m = ((int *) addr) + (nr >> 5);

	__asm__ __volatile__(
	"1:	ldl_l %0,%3\n"
	"	bic %0,%2,%0\n"
	"	stl_c %0,%1\n"
	"	beq %0,2f\n"
	".subsection 2\n"
	"2:	br 1b\n"
	".previous"
	:"=&r" (temp), "=m" (*m)
	:"Ir" (1UL << (nr & 31)), "m" (*m));
}

/*
 * WARNING: non atomic version.
 */
static __inline__ void
__clear_bit(unsigned long nr, volatile void * addr)
{
	int *m = ((int *) addr) + (nr >> 5);

	*m &= ~(1 << (nr & 31));
}

static inline void
change_bit(unsigned long nr, volatile void * addr)
{
	unsigned long temp;
	int *m = ((int *) addr) + (nr >> 5);

	__asm__ __volatile__(
	"1:	ldl_l %0,%3\n"
	"	xor %0,%2,%0\n"
	"	stl_c %0,%1\n"
	"	beq %0,2f\n"
	".subsection 2\n"
	"2:	br 1b\n"
	".previous"
	:"=&r" (temp), "=m" (*m)
	:"Ir" (1UL << (nr & 31)), "m" (*m));
}

/*
 * WARNING: non atomic version.
 */
static __inline__ void
__change_bit(unsigned long nr, volatile void * addr)
{
	int *m = ((int *) addr) + (nr >> 5);

	*m ^= 1 << (nr & 31);
}

static inline int
test_and_set_bit(unsigned long nr, volatile void *addr)
{
	unsigned long oldbit;
	unsigned long temp;
	int *m = ((int *) addr) + (nr >> 5);

	__asm__ __volatile__(
	"1:	ldl_l %0,%4\n"
	"	and %0,%3,%2\n"
	"	bne %2,2f\n"
	"	xor %0,%3,%0\n"
	"	stl_c %0,%1\n"
	"	beq %0,3f\n"
	"2:\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	".subsection 2\n"
	"3:	br 1b\n"
	".previous"
	:"=&r" (temp), "=m" (*m), "=&r" (oldbit)
	:"Ir" (1UL << (nr & 31)), "m" (*m) : "memory");

	return oldbit != 0;
}

/*
 * WARNING: non atomic version.
 */
static inline int
__test_and_set_bit(unsigned long nr, volatile void * addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	int *m = ((int *) addr) + (nr >> 5);
	int old = *m;

	*m = old | mask;
	return (old & mask) != 0;
}

static inline int
test_and_clear_bit(unsigned long nr, volatile void * addr)
{
	unsigned long oldbit;
	unsigned long temp;
	int *m = ((int *) addr) + (nr >> 5);

	__asm__ __volatile__(
	"1:	ldl_l %0,%4\n"
	"	and %0,%3,%2\n"
	"	beq %2,2f\n"
	"	xor %0,%3,%0\n"
	"	stl_c %0,%1\n"
	"	beq %0,3f\n"
	"2:\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	".subsection 2\n"
	"3:	br 1b\n"
	".previous"
	:"=&r" (temp), "=m" (*m), "=&r" (oldbit)
	:"Ir" (1UL << (nr & 31)), "m" (*m) : "memory");

	return oldbit != 0;
}

/*
 * WARNING: non atomic version.
 */
static inline int
__test_and_clear_bit(unsigned long nr, volatile void * addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	int *m = ((int *) addr) + (nr >> 5);
	int old = *m;

	*m = old & ~mask;
	return (old & mask) != 0;
}

static inline int
test_and_change_bit(unsigned long nr, volatile void * addr)
{
	unsigned long oldbit;
	unsigned long temp;
	int *m = ((int *) addr) + (nr >> 5);

	__asm__ __volatile__(
	"1:	ldl_l %0,%4\n"
	"	and %0,%3,%2\n"
	"	xor %0,%3,%0\n"
	"	stl_c %0,%1\n"
	"	beq %0,3f\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	".subsection 2\n"
	"3:	br 1b\n"
	".previous"
	:"=&r" (temp), "=m" (*m), "=&r" (oldbit)
	:"Ir" (1UL << (nr & 31)), "m" (*m) : "memory");

	return oldbit != 0;
}

/*
 * WARNING: non atomic version.
 */
static __inline__ int
__test_and_change_bit(unsigned long nr, volatile void * addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	int *m = ((int *) addr) + (nr >> 5);
	int old = *m;

	*m = old ^ mask;
	return (old & mask) != 0;
}

static inline int
test_bit(int nr, const volatile void * addr)
{
	return (1UL & (((const int *) addr)[nr >> 5] >> (nr & 31))) != 0UL;
}

/*
 * ffz = Find First Zero in word. Undefined if no zero exists,
 * so code should check against ~0UL first..
 *
 * Do a binary search on the bits.  Due to the nature of large
 * constants on the alpha, it is worthwhile to split the search.
 */
static inline unsigned long ffz_b(unsigned long x)
{
	unsigned long sum, x1, x2, x4;

	x = ~x & -~x;		/* set first 0 bit, clear others */
	x1 = x & 0xAA;
	x2 = x & 0xCC;
	x4 = x & 0xF0;
	sum = x2 ? 2 : 0;
	sum += (x4 != 0) * 4;
	sum += (x1 != 0);

	return sum;
}

static inline unsigned long ffz(unsigned long word)
{
#if defined(__alpha_cix__) && defined(__alpha_fix__)
	/* Whee.  EV67 can calculate it directly.  */
	return __kernel_cttz(~word);
#else
	unsigned long bits, qofs, bofs;

	bits = __kernel_cmpbge(word, ~0UL);
	qofs = ffz_b(bits);
	bits = __kernel_extbl(word, qofs);
	bofs = ffz_b(bits);

	return qofs*8 + bofs;
#endif
}

/*
 * __ffs = Find First set bit in word.  Undefined if no set bit exists.
 */
static inline unsigned long __ffs(unsigned long word)
{
#if defined(__alpha_cix__) && defined(__alpha_fix__)
	/* Whee.  EV67 can calculate it directly.  */
	return __kernel_cttz(word);
#else
	unsigned long bits, qofs, bofs;

	bits = __kernel_cmpbge(0, word);
	qofs = ffz_b(bits);
	bits = __kernel_extbl(word, qofs);
	bofs = ffz_b(~bits);

	return qofs*8 + bofs;
#endif
}

#ifdef __KERNEL__

/*
 * ffs: find first bit set. This is defined the same way as
 * the libc and compiler builtin ffs routines, therefore
 * differs in spirit from the above __ffs.
 */

static inline int ffs(int word)
{
	int result = __ffs(word) + 1;
	return word ? result : 0;
}

/*
 * fls: find last bit set.
 */
#if defined(__alpha_cix__) && defined(__alpha_fix__)
static inline int fls(int word)
{
	return 64 - __kernel_ctlz(word & 0xffffffff);
}
#else
#define fls	generic_fls
#endif

/* Compute powers of two for the given integer.  */
static inline long floor_log2(unsigned long word)
{
#if defined(__alpha_cix__) && defined(__alpha_fix__)
	return 63 - __kernel_ctlz(word);
#else
	long bit;
	for (bit = -1; word ; bit++)
		word >>= 1;
	return bit;
#endif
}

static inline long ceil_log2(unsigned long word)
{
	long bit = floor_log2(word);
	return bit + (word > (1UL << bit));
}

/*
 * hweightN: returns the hamming weight (i.e. the number
 * of bits set) of a N-bit word
 */

#if defined(__alpha_cix__) && defined(__alpha_fix__)
/* Whee.  EV67 can calculate it directly.  */
static inline unsigned long hweight64(unsigned long w)
{
	return __kernel_ctpop(w);
}

#define hweight32(x) hweight64((x) & 0xfffffffful)
#define hweight16(x) hweight64((x) & 0xfffful)
#define hweight8(x)  hweight64((x) & 0xfful)
#else
static inline unsigned long hweight64(unsigned long w)
{
	unsigned long result;
	for (result = 0; w ; w >>= 1)
		result += (w & 1);
	return result;
}

#define hweight32(x) generic_hweight32(x)
#define hweight16(x) generic_hweight16(x)
#define hweight8(x)  generic_hweight8(x)
#endif

#endif /* __KERNEL__ */

/*
 * Find next zero bit in a bitmap reasonably efficiently..
 */
static inline unsigned long
find_next_zero_bit(const void *addr, unsigned long size, unsigned long offset)
{
	const unsigned long *p = addr;
	unsigned long result = offset & ~63UL;
	unsigned long tmp;

	p += offset >> 6;
	if (offset >= size)
		return size;
	size -= result;
	offset &= 63UL;
	if (offset) {
		tmp = *(p++);
		tmp |= ~0UL >> (64-offset);
		if (size < 64)
			goto found_first;
		if (~tmp)
			goto found_middle;
		size -= 64;
		result += 64;
	}
	while (size & ~63UL) {
		if (~(tmp = *(p++)))
			goto found_middle;
		result += 64;
		size -= 64;
	}
	if (!size)
		return result;
	tmp = *p;
 found_first:
	tmp |= ~0UL << size;
	if (tmp == ~0UL)        /* Are any bits zero? */
		return result + size; /* Nope. */
 found_middle:
	return result + ffz(tmp);
}

/*
 * Find next one bit in a bitmap reasonably efficiently.
 */
static inline unsigned long
find_next_bit(const void * addr, unsigned long size, unsigned long offset)
{
	const unsigned long *p = addr;
	unsigned long result = offset & ~63UL;
	unsigned long tmp;

	p += offset >> 6;
	if (offset >= size)
		return size;
	size -= result;
	offset &= 63UL;
	if (offset) {
		tmp = *(p++);
		tmp &= ~0UL << offset;
		if (size < 64)
			goto found_first;
		if (tmp)
			goto found_middle;
		size -= 64;
		result += 64;
	}
	while (size & ~63UL) {
		if ((tmp = *(p++)))
			goto found_middle;
		result += 64;
		size -= 64;
	}
	if (!size)
		return result;
	tmp = *p;
 found_first:
	tmp &= ~0UL >> (64 - size);
	if (!tmp)
		return result + size;
 found_middle:
	return result + __ffs(tmp);
}

/*
 * The optimizer actually does good code for this case.
 */
#define find_first_zero_bit(addr, size) \
	find_next_zero_bit((addr), (size), 0)
#define find_first_bit(addr, size) \
	find_next_bit((addr), (size), 0)

#ifdef __KERNEL__

/*
 * Every architecture must define this function. It's the fastest
 * way of searching a 140-bit bitmap where the first 100 bits are
 * unlikely to be set. It's guaranteed that at least one of the 140
 * bits is set.
 */
static inline unsigned long
sched_find_first_bit(unsigned long b[3])
{
	unsigned long b0 = b[0], b1 = b[1], b2 = b[2];
	unsigned long ofs;

	ofs = (b1 ? 64 : 128);
	b1 = (b1 ? b1 : b2);
	ofs = (b0 ? 0 : ofs);
	b0 = (b0 ? b0 : b1);

	return __ffs(b0) + ofs;
}


#define ext2_set_bit                 __test_and_set_bit
#define ext2_set_bit_atomic(l,n,a)   test_and_set_bit(n,a)
#define ext2_clear_bit               __test_and_clear_bit
#define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a)
#define ext2_test_bit                test_bit
#define ext2_find_first_zero_bit     find_first_zero_bit
#define ext2_find_next_zero_bit      find_next_zero_bit

/* Bitmap functions for the minix filesystem.  */
#define minix_test_and_set_bit(nr,addr) __test_and_set_bit(nr,addr)
#define minix_set_bit(nr,addr) __set_bit(nr,addr)
#define minix_test_and_clear_bit(nr,addr) __test_and_clear_bit(nr,addr)
#define minix_test_bit(nr,addr) test_bit(nr,addr)
#define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size)

#endif /* __KERNEL__ */

#endif /* _ALPHA_BITOPS_H */