summaryrefslogblamecommitdiffstats
path: root/include/asm-mips/bitops.h
blob: eb8d79dba11ca104710662bf7fd8a2b941729187 (plain) (tree)
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
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535





















                                                                             
                                                     




                          
                                                     

























































































































































































































































































































































































































































































































                                                                                 
                   





                                                               
                   













































































































































                                                                          
                   









                                        
                   
























































































































































                                                                                
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (c) 1994 - 1997, 1999, 2000  Ralf Baechle (ralf@gnu.org)
 * Copyright (c) 1999, 2000  Silicon Graphics, Inc.
 */
#ifndef _ASM_BITOPS_H
#define _ASM_BITOPS_H

#include <linux/config.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/byteorder.h>		/* sigh ... */
#include <asm/cpu-features.h>

#if (_MIPS_SZLONG == 32)
#define SZLONG_LOG 5
#define SZLONG_MASK 31UL
#define __LL	"ll	"
#define __SC	"sc	"
#define cpu_to_lelongp(x) cpu_to_le32p((__u32 *) (x))
#elif (_MIPS_SZLONG == 64)
#define SZLONG_LOG 6
#define SZLONG_MASK 63UL
#define __LL	"lld	"
#define __SC	"scd	"
#define cpu_to_lelongp(x) cpu_to_le64p((__u64 *) (x))
#endif

#ifdef __KERNEL__

#include <asm/interrupt.h>
#include <asm/sgidefs.h>
#include <asm/war.h>

/*
 * clear_bit() doesn't provide any barrier for the compiler.
 */
#define smp_mb__before_clear_bit()	smp_mb()
#define smp_mb__after_clear_bit()	smp_mb()

/*
 * Only disable interrupt for kernel mode stuff to keep usermode stuff
 * that dares to use kernel include files alive.
 */

#define __bi_flags			unsigned long flags
#define __bi_local_irq_save(x)		local_irq_save(x)
#define __bi_local_irq_restore(x)	local_irq_restore(x)
#else
#define __bi_flags
#define __bi_local_irq_save(x)
#define __bi_local_irq_restore(x)
#endif /* __KERNEL__ */

/*
 * set_bit - Atomically set a bit in memory
 * @nr: the bit to set
 * @addr: the address to start counting from
 *
 * This function is atomic and may not be reordered.  See __set_bit()
 * if you do not require the atomic guarantees.
 * Note that @nr may be almost arbitrarily large; this function is not
 * restricted to acting on a single-word quantity.
 */
static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
{
	unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
	unsigned long temp;

	if (cpu_has_llsc && R10000_LLSC_WAR) {
		__asm__ __volatile__(
		"1:	" __LL "%0, %1			# set_bit	\n"
		"	or	%0, %2					\n"
		"	"__SC	"%0, %1					\n"
		"	beqzl	%0, 1b					\n"
		: "=&r" (temp), "=m" (*m)
		: "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
	} else if (cpu_has_llsc) {
		__asm__ __volatile__(
		"1:	" __LL "%0, %1			# set_bit	\n"
		"	or	%0, %2					\n"
		"	"__SC	"%0, %1					\n"
		"	beqz	%0, 1b					\n"
		: "=&r" (temp), "=m" (*m)
		: "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
	} else {
		volatile unsigned long *a = addr;
		unsigned long mask;
		__bi_flags;

		a += nr >> SZLONG_LOG;
		mask = 1UL << (nr & SZLONG_MASK);
		__bi_local_irq_save(flags);
		*a |= mask;
		__bi_local_irq_restore(flags);
	}
}

/*
 * __set_bit - Set a bit in memory
 * @nr: the bit to set
 * @addr: the address to start counting from
 *
 * Unlike set_bit(), this function is non-atomic and may be reordered.
 * If it's called on the same region of memory simultaneously, the effect
 * may be that only one operation succeeds.
 */
static inline void __set_bit(unsigned long nr, volatile unsigned long * addr)
{
	unsigned long * m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);

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

/*
 * clear_bit - Clears a bit in memory
 * @nr: Bit to clear
 * @addr: Address to start counting from
 *
 * clear_bit() is atomic and may not be reordered.  However, it does
 * not contain a memory barrier, so if it is used for locking purposes,
 * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
 * in order to ensure changes are visible on other processors.
 */
static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
{
	unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
	unsigned long temp;

	if (cpu_has_llsc && R10000_LLSC_WAR) {
		__asm__ __volatile__(
		"1:	" __LL "%0, %1			# clear_bit	\n"
		"	and	%0, %2					\n"
		"	" __SC "%0, %1					\n"
		"	beqzl	%0, 1b					\n"
		: "=&r" (temp), "=m" (*m)
		: "ir" (~(1UL << (nr & SZLONG_MASK))), "m" (*m));
	} else if (cpu_has_llsc) {
		__asm__ __volatile__(
		"1:	" __LL "%0, %1			# clear_bit	\n"
		"	and	%0, %2					\n"
		"	" __SC "%0, %1					\n"
		"	beqz	%0, 1b					\n"
		: "=&r" (temp), "=m" (*m)
		: "ir" (~(1UL << (nr & SZLONG_MASK))), "m" (*m));
	} else {
		volatile unsigned long *a = addr;
		unsigned long mask;
		__bi_flags;

		a += nr >> SZLONG_LOG;
		mask = 1UL << (nr & SZLONG_MASK);
		__bi_local_irq_save(flags);
		*a &= ~mask;
		__bi_local_irq_restore(flags);
	}
}

/*
 * __clear_bit - Clears a bit in memory
 * @nr: Bit to clear
 * @addr: Address to start counting from
 *
 * Unlike clear_bit(), this function is non-atomic and may be reordered.
 * If it's called on the same region of memory simultaneously, the effect
 * may be that only one operation succeeds.
 */
static inline void __clear_bit(unsigned long nr, volatile unsigned long * addr)
{
	unsigned long * m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);

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

/*
 * change_bit - Toggle a bit in memory
 * @nr: Bit to change
 * @addr: Address to start counting from
 *
 * change_bit() is atomic and may not be reordered.
 * Note that @nr may be almost arbitrarily large; this function is not
 * restricted to acting on a single-word quantity.
 */
static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
{
	if (cpu_has_llsc && R10000_LLSC_WAR) {
		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
		unsigned long temp;

		__asm__ __volatile__(
		"1:	" __LL "%0, %1		# change_bit	\n"
		"	xor	%0, %2				\n"
		"	"__SC	"%0, %1				\n"
		"	beqzl	%0, 1b				\n"
		: "=&r" (temp), "=m" (*m)
		: "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
	} else if (cpu_has_llsc) {
		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
		unsigned long temp;

		__asm__ __volatile__(
		"1:	" __LL "%0, %1		# change_bit	\n"
		"	xor	%0, %2				\n"
		"	"__SC	"%0, %1				\n"
		"	beqz	%0, 1b				\n"
		: "=&r" (temp), "=m" (*m)
		: "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
	} else {
		volatile unsigned long *a = addr;
		unsigned long mask;
		__bi_flags;

		a += nr >> SZLONG_LOG;
		mask = 1UL << (nr & SZLONG_MASK);
		__bi_local_irq_save(flags);
		*a ^= mask;
		__bi_local_irq_restore(flags);
	}
}

/*
 * __change_bit - Toggle a bit in memory
 * @nr: the bit to change
 * @addr: the address to start counting from
 *
 * Unlike change_bit(), this function is non-atomic and may be reordered.
 * If it's called on the same region of memory simultaneously, the effect
 * may be that only one operation succeeds.
 */
static inline void __change_bit(unsigned long nr, volatile unsigned long * addr)
{
	unsigned long * m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);

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

/*
 * test_and_set_bit - Set a bit and return its old value
 * @nr: Bit to set
 * @addr: Address to count from
 *
 * This operation is atomic and cannot be reordered.
 * It also implies a memory barrier.
 */
static inline int test_and_set_bit(unsigned long nr,
	volatile unsigned long *addr)
{
	if (cpu_has_llsc && R10000_LLSC_WAR) {
		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
		unsigned long temp, res;

		__asm__ __volatile__(
		"1:	" __LL "%0, %1		# test_and_set_bit	\n"
		"	or	%2, %0, %3				\n"
		"	" __SC	"%2, %1					\n"
		"	beqzl	%2, 1b					\n"
		"	and	%2, %0, %3				\n"
#ifdef CONFIG_SMP
		"sync							\n"
#endif
		: "=&r" (temp), "=m" (*m), "=&r" (res)
		: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
		: "memory");

		return res != 0;
	} else if (cpu_has_llsc) {
		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
		unsigned long temp, res;

		__asm__ __volatile__(
		"	.set	noreorder	# test_and_set_bit	\n"
		"1:	" __LL "%0, %1					\n"
		"	or	%2, %0, %3				\n"
		"	" __SC	"%2, %1					\n"
		"	beqz	%2, 1b					\n"
		"	 and	%2, %0, %3				\n"
#ifdef CONFIG_SMP
		"sync							\n"
#endif
		".set\treorder"
		: "=&r" (temp), "=m" (*m), "=&r" (res)
		: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
		: "memory");

		return res != 0;
	} else {
		volatile unsigned long *a = addr;
		unsigned long mask;
		int retval;
		__bi_flags;

		a += nr >> SZLONG_LOG;
		mask = 1UL << (nr & SZLONG_MASK);
		__bi_local_irq_save(flags);
		retval = (mask & *a) != 0;
		*a |= mask;
		__bi_local_irq_restore(flags);

		return retval;
	}
}

/*
 * __test_and_set_bit - Set a bit and return its old value
 * @nr: Bit to set
 * @addr: Address to count from
 *
 * This operation is non-atomic and can be reordered.
 * If two examples of this operation race, one can appear to succeed
 * but actually fail.  You must protect multiple accesses with a lock.
 */
static inline int __test_and_set_bit(unsigned long nr,
	volatile unsigned long *addr)
{
	volatile unsigned long *a = addr;
	unsigned long mask;
	int retval;

	a += nr >> SZLONG_LOG;
	mask = 1UL << (nr & SZLONG_MASK);
	retval = (mask & *a) != 0;
	*a |= mask;

	return retval;
}

/*
 * test_and_clear_bit - Clear a bit and return its old value
 * @nr: Bit to clear
 * @addr: Address to count from
 *
 * This operation is atomic and cannot be reordered.
 * It also implies a memory barrier.
 */
static inline int test_and_clear_bit(unsigned long nr,
	volatile unsigned long *addr)
{
	if (cpu_has_llsc && R10000_LLSC_WAR) {
		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
		unsigned long temp, res;

		__asm__ __volatile__(
		"1:	" __LL	"%0, %1		# test_and_clear_bit	\n"
		"	or	%2, %0, %3				\n"
		"	xor	%2, %3					\n"
			__SC 	"%2, %1					\n"
		"	beqzl	%2, 1b					\n"
		"	and	%2, %0, %3				\n"
#ifdef CONFIG_SMP
		"	sync						\n"
#endif
		: "=&r" (temp), "=m" (*m), "=&r" (res)
		: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
		: "memory");

		return res != 0;
	} else if (cpu_has_llsc) {
		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
		unsigned long temp, res;

		__asm__ __volatile__(
		"	.set	noreorder	# test_and_clear_bit	\n"
		"1:	" __LL	"%0, %1					\n"
		"	or	%2, %0, %3				\n"
		"	xor	%2, %3					\n"
			__SC 	"%2, %1					\n"
		"	beqz	%2, 1b					\n"
		"	 and	%2, %0, %3				\n"
#ifdef CONFIG_SMP
		"	sync						\n"
#endif
		"	.set	reorder					\n"
		: "=&r" (temp), "=m" (*m), "=&r" (res)
		: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
		: "memory");

		return res != 0;
	} else {
		volatile unsigned long *a = addr;
		unsigned long mask;
		int retval;
		__bi_flags;

		a += nr >> SZLONG_LOG;
		mask = 1UL << (nr & SZLONG_MASK);
		__bi_local_irq_save(flags);
		retval = (mask & *a) != 0;
		*a &= ~mask;
		__bi_local_irq_restore(flags);

		return retval;
	}
}

/*
 * __test_and_clear_bit - Clear a bit and return its old value
 * @nr: Bit to clear
 * @addr: Address to count from
 *
 * This operation is non-atomic and can be reordered.
 * If two examples of this operation race, one can appear to succeed
 * but actually fail.  You must protect multiple accesses with a lock.
 */
static inline int __test_and_clear_bit(unsigned long nr,
	volatile unsigned long * addr)
{
	volatile unsigned long *a = addr;
	unsigned long mask;
	int retval;

	a += (nr >> SZLONG_LOG);
	mask = 1UL << (nr & SZLONG_MASK);
	retval = ((mask & *a) != 0);
	*a &= ~mask;

	return retval;
}

/*
 * test_and_change_bit - Change a bit and return its old value
 * @nr: Bit to change
 * @addr: Address to count from
 *
 * This operation is atomic and cannot be reordered.
 * It also implies a memory barrier.
 */
static inline int test_and_change_bit(unsigned long nr,
	volatile unsigned long *addr)
{
	if (cpu_has_llsc && R10000_LLSC_WAR) {
		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
		unsigned long temp, res;

		__asm__ __volatile__(
		"1:	" __LL	" %0, %1	# test_and_change_bit	\n"
		"	xor	%2, %0, %3				\n"
		"	"__SC	"%2, %1					\n"
		"	beqzl	%2, 1b					\n"
		"	and	%2, %0, %3				\n"
#ifdef CONFIG_SMP
		"	sync						\n"
#endif
		: "=&r" (temp), "=m" (*m), "=&r" (res)
		: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
		: "memory");

		return res != 0;
	} else if (cpu_has_llsc) {
		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
		unsigned long temp, res;

		__asm__ __volatile__(
		"	.set	noreorder	# test_and_change_bit	\n"
		"1:	" __LL	" %0, %1				\n"
		"	xor	%2, %0, %3				\n"
		"	"__SC	"\t%2, %1				\n"
		"	beqz	%2, 1b					\n"
		"	 and	%2, %0, %3				\n"
#ifdef CONFIG_SMP
		"	sync						\n"
#endif
		"	.set	reorder					\n"
		: "=&r" (temp), "=m" (*m), "=&r" (res)
		: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
		: "memory");

		return res != 0;
	} else {
		volatile unsigned long *a = addr;
		unsigned long mask, retval;
		__bi_flags;

		a += nr >> SZLONG_LOG;
		mask = 1UL << (nr & SZLONG_MASK);
		__bi_local_irq_save(flags);
		retval = (mask & *a) != 0;
		*a ^= mask;
		__bi_local_irq_restore(flags);

		return retval;
	}
}

/*
 * __test_and_change_bit - Change a bit and return its old value
 * @nr: Bit to change
 * @addr: Address to count from
 *
 * This operation is non-atomic and can be reordered.
 * If two examples of this operation race, one can appear to succeed
 * but actually fail.  You must protect multiple accesses with a lock.
 */
static inline int __test_and_change_bit(unsigned long nr,
	volatile unsigned long *addr)
{
	volatile unsigned long *a = addr;
	unsigned long mask;
	int retval;

	a += (nr >> SZLONG_LOG);
	mask = 1UL << (nr & SZLONG_MASK);
	retval = ((mask & *a) != 0);
	*a ^= mask;

	return retval;
}

#undef __bi_flags
#undef __bi_local_irq_save
#undef __bi_local_irq_restore

/*
 * test_bit - Determine whether a bit is set
 * @nr: bit number to test
 * @addr: Address to start counting from
 */
static inline int test_bit(unsigned long nr, const volatile unsigned long *addr)
{
	return 1UL & (addr[nr >> SZLONG_LOG] >> (nr & SZLONG_MASK));
}

/*
 * ffz - find first zero in word.
 * @word: The word to search
 *
 * Undefined if no zero exists, so code should check against ~0UL first.
 */
static inline unsigned long ffz(unsigned long word)
{
	int b = 0, s;

	word = ~word;
#ifdef CONFIG_32BIT
	s = 16; if (word << 16 != 0) s = 0; b += s; word >>= s;
	s =  8; if (word << 24 != 0) s = 0; b += s; word >>= s;
	s =  4; if (word << 28 != 0) s = 0; b += s; word >>= s;
	s =  2; if (word << 30 != 0) s = 0; b += s; word >>= s;
	s =  1; if (word << 31 != 0) s = 0; b += s;
#endif
#ifdef CONFIG_64BIT
	s = 32; if (word << 32 != 0) s = 0; b += s; word >>= s;
	s = 16; if (word << 48 != 0) s = 0; b += s; word >>= s;
	s =  8; if (word << 56 != 0) s = 0; b += s; word >>= s;
	s =  4; if (word << 60 != 0) s = 0; b += s; word >>= s;
	s =  2; if (word << 62 != 0) s = 0; b += s; word >>= s;
	s =  1; if (word << 63 != 0) s = 0; b += s;
#endif

	return b;
}

/*
 * __ffs - find first bit in word.
 * @word: The word to search
 *
 * Undefined if no bit exists, so code should check against 0 first.
 */
static inline unsigned long __ffs(unsigned long word)
{
	return ffz(~word);
}

/*
 * fls: find last bit set.
 */

#define fls(x) generic_fls(x)

/*
 * find_next_zero_bit - find the first zero bit in a memory region
 * @addr: The address to base the search on
 * @offset: The bitnumber to start searching at
 * @size: The maximum size to search
 */
static inline unsigned long find_next_zero_bit(const unsigned long *addr,
	unsigned long size, unsigned long offset)
{
	const unsigned long *p = addr + (offset >> SZLONG_LOG);
	unsigned long result = offset & ~SZLONG_MASK;
	unsigned long tmp;

	if (offset >= size)
		return size;
	size -= result;
	offset &= SZLONG_MASK;
	if (offset) {
		tmp = *(p++);
		tmp |= ~0UL >> (_MIPS_SZLONG-offset);
		if (size < _MIPS_SZLONG)
			goto found_first;
		if (~tmp)
			goto found_middle;
		size -= _MIPS_SZLONG;
		result += _MIPS_SZLONG;
	}
	while (size & ~SZLONG_MASK) {
		if (~(tmp = *(p++)))
			goto found_middle;
		result += _MIPS_SZLONG;
		size -= _MIPS_SZLONG;
	}
	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);
}

#define find_first_zero_bit(addr, size) \
	find_next_zero_bit((addr), (size), 0)

/*
 * find_next_bit - find the next set bit in a memory region
 * @addr: The address to base the search on
 * @offset: The bitnumber to start searching at
 * @size: The maximum size to search
 */
static inline unsigned long find_next_bit(const unsigned long *addr,
	unsigned long size, unsigned long offset)
{
	const unsigned long *p = addr + (offset >> SZLONG_LOG);
	unsigned long result = offset & ~SZLONG_MASK;
	unsigned long tmp;

	if (offset >= size)
		return size;
	size -= result;
	offset &= SZLONG_MASK;
	if (offset) {
		tmp = *(p++);
		tmp &= ~0UL << offset;
		if (size < _MIPS_SZLONG)
			goto found_first;
		if (tmp)
			goto found_middle;
		size -= _MIPS_SZLONG;
		result += _MIPS_SZLONG;
	}
	while (size & ~SZLONG_MASK) {
		if ((tmp = *(p++)))
			goto found_middle;
		result += _MIPS_SZLONG;
		size -= _MIPS_SZLONG;
	}
	if (!size)
		return result;
	tmp = *p;

found_first:
	tmp &= ~0UL >> (_MIPS_SZLONG - size);
	if (tmp == 0UL)			/* Are any bits set? */
		return result + size;	/* Nope. */
found_middle:
	return result + __ffs(tmp);
}

/*
 * find_first_bit - find the first set bit in a memory region
 * @addr: The address to start the search at
 * @size: The maximum size to search
 *
 * Returns the bit-number of the first set bit, not the number of the byte
 * containing a bit.
 */
#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 cleared.
 */
static inline int sched_find_first_bit(const unsigned long *b)
{
#ifdef CONFIG_32BIT
	if (unlikely(b[0]))
		return __ffs(b[0]);
	if (unlikely(b[1]))
		return __ffs(b[1]) + 32;
	if (unlikely(b[2]))
		return __ffs(b[2]) + 64;
	if (b[3])
		return __ffs(b[3]) + 96;
	return __ffs(b[4]) + 128;
#endif
#ifdef CONFIG_64BIT
	if (unlikely(b[0]))
		return __ffs(b[0]);
	if (unlikely(b[1]))
		return __ffs(b[1]) + 64;
	return __ffs(b[2]) + 128;
#endif
}

/*
 * ffs - find first bit set
 * @x: the word to search
 *
 * This is defined the same way as
 * the libc and compiler builtin ffs routines, therefore
 * differs in spirit from the above ffz (man ffs).
 */

#define ffs(x) generic_ffs(x)

/*
 * hweightN - returns the hamming weight of a N-bit word
 * @x: the word to weigh
 *
 * The Hamming Weight of a number is the total number of bits set in it.
 */

#define hweight64(x)	generic_hweight64(x)
#define hweight32(x)	generic_hweight32(x)
#define hweight16(x)	generic_hweight16(x)
#define hweight8(x)	generic_hweight8(x)

static inline int __test_and_set_le_bit(unsigned long nr, unsigned long *addr)
{
	unsigned char	*ADDR = (unsigned char *) addr;
	int		mask, retval;

	ADDR += nr >> 3;
	mask = 1 << (nr & 0x07);
	retval = (mask & *ADDR) != 0;
	*ADDR |= mask;

	return retval;
}

static inline int __test_and_clear_le_bit(unsigned long nr, unsigned long *addr)
{
	unsigned char	*ADDR = (unsigned char *) addr;
	int		mask, retval;

	ADDR += nr >> 3;
	mask = 1 << (nr & 0x07);
	retval = (mask & *ADDR) != 0;
	*ADDR &= ~mask;

	return retval;
}

static inline int test_le_bit(unsigned long nr, const unsigned long * addr)
{
	const unsigned char	*ADDR = (const unsigned char *) addr;
	int			mask;

	ADDR += nr >> 3;
	mask = 1 << (nr & 0x07);

	return ((mask & *ADDR) != 0);
}

static inline unsigned long find_next_zero_le_bit(unsigned long *addr,
	unsigned long size, unsigned long offset)
{
	unsigned long *p = ((unsigned long *) addr) + (offset >> SZLONG_LOG);
	unsigned long result = offset & ~SZLONG_MASK;
	unsigned long tmp;

	if (offset >= size)
		return size;
	size -= result;
	offset &= SZLONG_MASK;
	if (offset) {
		tmp = cpu_to_lelongp(p++);
		tmp |= ~0UL >> (_MIPS_SZLONG-offset); /* bug or feature ? */
		if (size < _MIPS_SZLONG)
			goto found_first;
		if (~tmp)
			goto found_middle;
		size -= _MIPS_SZLONG;
		result += _MIPS_SZLONG;
	}
	while (size & ~SZLONG_MASK) {
		if (~(tmp = cpu_to_lelongp(p++)))
			goto found_middle;
		result += _MIPS_SZLONG;
		size -= _MIPS_SZLONG;
	}
	if (!size)
		return result;
	tmp = cpu_to_lelongp(p);

found_first:
	tmp |= ~0UL << size;
	if (tmp == ~0UL)		/* Are any bits zero? */
		return result + size;	/* Nope. */

found_middle:
	return result + ffz(tmp);
}

#define find_first_zero_le_bit(addr, size) \
	find_next_zero_le_bit((addr), (size), 0)

#define ext2_set_bit(nr,addr) \
	__test_and_set_le_bit((nr),(unsigned long*)addr)
#define ext2_clear_bit(nr, addr) \
	__test_and_clear_le_bit((nr),(unsigned long*)addr)
 #define ext2_set_bit_atomic(lock, nr, addr)		\
({							\
	int ret;					\
	spin_lock(lock);				\
	ret = ext2_set_bit((nr), (addr));		\
	spin_unlock(lock);				\
	ret;						\
})

#define ext2_clear_bit_atomic(lock, nr, addr)		\
({							\
	int ret;					\
	spin_lock(lock);				\
	ret = ext2_clear_bit((nr), (addr));		\
	spin_unlock(lock);				\
	ret;						\
})
#define ext2_test_bit(nr, addr)	test_le_bit((nr),(unsigned long*)addr)
#define ext2_find_first_zero_bit(addr, size) \
	find_first_zero_le_bit((unsigned long*)addr, size)
#define ext2_find_next_zero_bit(addr, size, off) \
	find_next_zero_le_bit((unsigned long*)addr, size, off)

/*
 * Bitmap functions for the minix filesystem.
 *
 * FIXME: These assume that Minix uses the native byte/bitorder.
 * This limits the Minix filesystem's value for data exchange very much.
 */
#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 /* _ASM_BITOPS_H */