[deliverable/linux.git] / include / asm-xtensa / bitops.h

/*
 * include/asm-xtensa/bitops.h
 *
 * Atomic operations that C can't guarantee us.Useful for resource counting etc.
 *
 * 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) 2001 - 2005 Tensilica Inc.
 */

#ifndef _XTENSA_BITOPS_H
#define _XTENSA_BITOPS_H

#ifdef __KERNEL__

#include <asm/processor.h>
#include <asm/byteorder.h>
#include <asm/system.h>

#ifdef CONFIG_SMP
# error SMP not supported on this architecture
#endif

static __inline__ void set_bit(int nr, volatile void * addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);
	unsigned long flags;

	local_irq_save(flags);
	*a |= mask;
	local_irq_restore(flags);
}

static __inline__ void __set_bit(int nr, volatile unsigned long * addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);

	*a |= mask;
}

static __inline__ void clear_bit(int nr, volatile void * addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);
	unsigned long flags;

	local_irq_save(flags);
	*a &= ~mask;
	local_irq_restore(flags);
}

static __inline__ void __clear_bit(int nr, volatile unsigned long *addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);

	*a &= ~mask;
}

/*
 * clear_bit() doesn't provide any barrier for the compiler.
 */

#define smp_mb__before_clear_bit()	barrier()
#define smp_mb__after_clear_bit()	barrier()

static __inline__ void change_bit(int nr, volatile void * addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);
	unsigned long flags;

	local_irq_save(flags);
	*a ^= mask;
	local_irq_restore(flags);
}

static __inline__ void __change_bit(int nr, volatile void * addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);

	*a ^= mask;
}

static __inline__ int test_and_set_bit(int nr, volatile void * addr)
{
  	unsigned long retval;
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);
	unsigned long flags;

	local_irq_save(flags);
	retval = (mask & *a) != 0;
	*a |= mask;
	local_irq_restore(flags);

	return retval;
}

static __inline__ int __test_and_set_bit(int nr, volatile void * addr)
{
  	unsigned long retval;
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);

	retval = (mask & *a) != 0;
	*a |= mask;

	return retval;
}

static __inline__ int test_and_clear_bit(int nr, volatile void * addr)
{
  	unsigned long retval;
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);
	unsigned long flags;

	local_irq_save(flags);
	retval = (mask & *a) != 0;
	*a &= ~mask;
	local_irq_restore(flags);

	return retval;
}

static __inline__ int __test_and_clear_bit(int nr, volatile void * addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);
  	unsigned long old = *a;

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

static __inline__ int test_and_change_bit(int nr, volatile void * addr)
{
  	unsigned long retval;
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);
	unsigned long flags;

	local_irq_save(flags);

	retval = (mask & *a) != 0;
	*a ^= mask;
	local_irq_restore(flags);

	return retval;
}

/*
 * non-atomic version; can be reordered
 */

static __inline__ int __test_and_change_bit(int nr, volatile void *addr)
{
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long *a = ((unsigned long *)addr) + (nr >> 5);
	unsigned long old = *a;

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

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

#if XCHAL_HAVE_NSA

static __inline__ int __cntlz (unsigned long x)
{
	int lz;
	asm ("nsau %0, %1" : "=r" (lz) : "r" (x));
	return 31 - lz;
}

#else

static __inline__ int __cntlz (unsigned long x)
{
	unsigned long sum, x1, x2, x4, x8, x16;
	x1  = x & 0xAAAAAAAA;
	x2  = x & 0xCCCCCCCC;
	x4  = x & 0xF0F0F0F0;
	x8  = x & 0xFF00FF00;
	x16 = x & 0xFFFF0000;
	sum = x2 ? 2 : 0;
	sum += (x16 != 0) * 16;
	sum += (x8 != 0) * 8;
	sum += (x4 != 0) * 4;
	sum += (x1 != 0);

	return sum;
}

#endif

/*
 * ffz: Find first zero in word. Undefined if no zero exists.
 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
 */

static __inline__ int ffz(unsigned long x)
{
	if ((x = ~x) == 0)
		return 32;
	return __cntlz(x & -x);
}

/*
 * __ffs: Find first bit set in word. Return 0 for bit 0
 */

static __inline__ int __ffs(unsigned long x)
{
	return __cntlz(x & -x);
}

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

static __inline__ int ffs(unsigned long x)
{
	return __cntlz(x & -x) + 1;
}

/*
 * fls: Find last (most-significant) bit set in word.
 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
 */

static __inline__ int fls (unsigned int x)
{
	return __cntlz(x);
}
#define fls64(x)   generic_fls64(x)

static __inline__ int
find_next_bit(const unsigned long *addr, int size, int offset)
{
	const unsigned long *p = addr + (offset >> 5);
	unsigned long result = offset & ~31UL;
	unsigned long tmp;

	if (offset >= size)
		return size;
	size -= result;
	offset &= 31UL;
	if (offset) {
		tmp = *p++;
		tmp &= ~0UL << offset;
		if (size < 32)
			goto found_first;
		if (tmp)
			goto found_middle;
		size -= 32;
		result += 32;
	}
	while (size >= 32) {
		if ((tmp = *p++) != 0)
			goto found_middle;
		result += 32;
		size -= 32;
	}
	if (!size)
		return result;
	tmp = *p;

found_first:
	tmp &= ~0UL >> (32 - 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)

static __inline__ int
find_next_zero_bit(const unsigned long *addr, int size, int offset)
{
	const unsigned long *p = addr + (offset >> 5);
	unsigned long result = offset & ~31UL;
	unsigned long tmp;

	if (offset >= size)
		return size;
	size -= result;
	offset &= 31UL;
	if (offset) {
		tmp = *p++;
		tmp |= ~0UL >> (32-offset);
		if (size < 32)
			goto found_first;
		if (~tmp)
			goto found_middle;
		size -= 32;
		result += 32;
	}
	while (size & ~31UL) {
		if (~(tmp = *p++))
			goto found_middle;
		result += 32;
		size -= 32;
	}
	if (!size)
		return result;
	tmp = *p;

found_first:
	tmp |= ~0UL << size;
found_middle:
	return result + ffz(tmp);
}

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

#ifdef __XTENSA_EL__
# define ext2_set_bit(nr,addr) __test_and_set_bit((nr), (addr))
# define ext2_set_bit_atomic(lock,nr,addr) test_and_set_bit((nr),(addr))
# define ext2_clear_bit(nr,addr) __test_and_clear_bit((nr), (addr))
# define ext2_clear_bit_atomic(lock,nr,addr) test_and_clear_bit((nr),(addr))
# define ext2_test_bit(nr,addr) test_bit((nr), (addr))
# define ext2_find_first_zero_bit(addr, size) find_first_zero_bit((addr),(size))
# define ext2_find_next_zero_bit(addr, size, offset) \
                find_next_zero_bit((addr), (size), (offset))
#elif defined(__XTENSA_EB__)
# define ext2_set_bit(nr,addr) __test_and_set_bit((nr) ^ 0x18, (addr))
# define ext2_set_bit_atomic(lock,nr,addr) test_and_set_bit((nr) ^ 0x18, (addr))
# define ext2_clear_bit(nr,addr) __test_and_clear_bit((nr) ^ 18, (addr))
# define ext2_clear_bit_atomic(lock,nr,addr) test_and_clear_bit((nr)^0x18,(addr))
# define ext2_test_bit(nr,addr) test_bit((nr) ^ 0x18, (addr))
# define ext2_find_first_zero_bit(addr, size) \
        ext2_find_next_zero_bit((addr), (size), 0)

static __inline__ unsigned long ext2_find_next_zero_bit(void *addr, unsigned long size, unsigned long offset)
{
	unsigned long *p = ((unsigned long *) addr) + (offset >> 5);
	unsigned long result = offset & ~31UL;
	unsigned long tmp;

	if (offset >= size)
		return size;
	size -= result;
	offset &= 31UL;
	if(offset) {
		/* We hold the little endian value in tmp, but then the
		 * shift is illegal. So we could keep a big endian value
		 * in tmp, like this:
		 *
		 * tmp = __swab32(*(p++));
		 * tmp |= ~0UL >> (32-offset);
		 *
		 * but this would decrease preformance, so we change the
		 * shift:
		 */
		tmp = *(p++);
		tmp |= __swab32(~0UL >> (32-offset));
		if(size < 32)
			goto found_first;
		if(~tmp)
			goto found_middle;
		size -= 32;
		result += 32;
	}
	while(size & ~31UL) {
		if(~(tmp = *(p++)))
			goto found_middle;
		result += 32;
		size -= 32;
	}
	if(!size)
		return result;
	tmp = *p;

found_first:
	/* tmp is little endian, so we would have to swab the shift,
	 * see above. But then we have to swab tmp below for ffz, so
	 * we might as well do this here.
	 */
	return result + ffz(__swab32(tmp) | (~0UL << size));
found_middle:
	return result + ffz(__swab32(tmp));
}

#else
# error processor byte order undefined!
#endif


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

/*
 * Find the first bit set in a 140-bit bitmap.
 * The first 100 bits are unlikely to be set.
 */

static inline int sched_find_first_bit(const unsigned long *b)
{
	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;
}


/* 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	/* _XTENSA_BITOPS_H */
Commit	Line	Data
9a8fd558 CZ	1	/*
	2	* include/asm-xtensa/bitops.h
	3	*
	4	* Atomic operations that C can't guarantee us.Useful for resource counting etc.
	5	*
	6	* This file is subject to the terms and conditions of the GNU General Public
	7	* License. See the file "COPYING" in the main directory of this archive
	8	* for more details.
	9	*
	10	* Copyright (C) 2001 - 2005 Tensilica Inc.
	11	*/
	12
	13	#ifndef _XTENSA_BITOPS_H
	14	#define _XTENSA_BITOPS_H
	15
	16	#ifdef __KERNEL__
	17
	18	#include <asm/processor.h>
	19	#include <asm/byteorder.h>
	20	#include <asm/system.h>
	21
	22	#ifdef CONFIG_SMP
	23	# error SMP not supported on this architecture
	24	#endif
	25
	26	static __inline__ void set_bit(int nr, volatile void * addr)
	27	{
	28	unsigned long mask = 1 << (nr & 0x1f);
	29	unsigned long a = ((unsigned long )addr) + (nr >> 5);
	30	unsigned long flags;
	31
	32	local_irq_save(flags);
	33	*a \|= mask;
	34	local_irq_restore(flags);
	35	}
	36
	37	static __inline__ void __set_bit(int nr, volatile unsigned long * addr)
	38	{
	39	unsigned long mask = 1 << (nr & 0x1f);
	40	unsigned long a = ((unsigned long )addr) + (nr >> 5);
	41
	42	*a \|= mask;
	43	}
	44
	45	static __inline__ void clear_bit(int nr, volatile void * addr)
	46	{
	47	unsigned long mask = 1 << (nr & 0x1f);
	48	unsigned long a = ((unsigned long )addr) + (nr >> 5);
	49	unsigned long flags;
	50
	51	local_irq_save(flags);
	52	*a &= ~mask;
	53	local_irq_restore(flags);
	54	}
	55
	56	static __inline__ void __clear_bit(int nr, volatile unsigned long *addr)
	57	{
	58	unsigned long mask = 1 << (nr & 0x1f);
	59	unsigned long a = ((unsigned long )addr) + (nr >> 5);
	60
	61	*a &= ~mask;
	62	}
	63
	64	/*
65	* clear_bit() doesn't provide any barrier for the compiler.
66	*/
67
68	#define smp_mb__before_clear_bit() barrier()
69	#define smp_mb__after_clear_bit() barrier()
70
71	static __inline__ void change_bit(int nr, volatile void * addr)
72	{
73	unsigned long mask = 1 << (nr & 0x1f);
74	unsigned long a = ((unsigned long )addr) + (nr >> 5);
75	unsigned long flags;
76
77	local_irq_save(flags);
78	*a ^= mask;
79	local_irq_restore(flags);
80	}
81
82	static __inline__ void __change_bit(int nr, volatile void * addr)
83	{
84	unsigned long mask = 1 << (nr & 0x1f);
85	unsigned long a = ((unsigned long )addr) + (nr >> 5);
86
87	*a ^= mask;
88	}
89
90	static __inline__ int test_and_set_bit(int nr, volatile void * addr)
91	{
92	unsigned long retval;
93	unsigned long mask = 1 << (nr & 0x1f);
94	unsigned long a = ((unsigned long )addr) + (nr >> 5);
95	unsigned long flags;
96
97	local_irq_save(flags);
98	retval = (mask & *a) != 0;
99	*a \|= mask;
100	local_irq_restore(flags);
101
102	return retval;
103	}
104
105	static __inline__ int __test_and_set_bit(int nr, volatile void * addr)
106	{
107	unsigned long retval;
108	unsigned long mask = 1 << (nr & 0x1f);
109	unsigned long a = ((unsigned long )addr) + (nr >> 5);
110
111	retval = (mask & *a) != 0;
112	*a \|= mask;
113
114	return retval;
115	}
116
117	static __inline__ int test_and_clear_bit(int nr, volatile void * addr)
118	{
119	unsigned long retval;
120	unsigned long mask = 1 << (nr & 0x1f);
121	unsigned long a = ((unsigned long )addr) + (nr >> 5);
122	unsigned long flags;
123
124	local_irq_save(flags);
125	retval = (mask & *a) != 0;
126	*a &= ~mask;
127	local_irq_restore(flags);
128
129	return retval;
130	}
131
132	static __inline__ int __test_and_clear_bit(int nr, volatile void * addr)
133	{
134	unsigned long mask = 1 << (nr & 0x1f);
135	unsigned long a = ((unsigned long )addr) + (nr >> 5);
136	unsigned long old = *a;
137
138	*a = old & ~mask;
139	return (old & mask) != 0;
140	}
141
142	static __inline__ int test_and_change_bit(int nr, volatile void * addr)
143	{
144	unsigned long retval;
145	unsigned long mask = 1 << (nr & 0x1f);
146	unsigned long a = ((unsigned long )addr) + (nr >> 5);
147	unsigned long flags;
148
149	local_irq_save(flags);
150
151	retval = (mask & *a) != 0;
152	*a ^= mask;
153	local_irq_restore(flags);
154
155	return retval;
156	}
157
158	/*
159	* non-atomic version; can be reordered
160	*/
161
162	static __inline__ int __test_and_change_bit(int nr, volatile void *addr)
163	{
164	unsigned long mask = 1 << (nr & 0x1f);
165	unsigned long a = ((unsigned long )addr) + (nr >> 5);
166	unsigned long old = *a;
167
168	*a = old ^ mask;
169	return (old & mask) != 0;
170	}
171
172	static __inline__ int test_bit(int nr, const volatile void *addr)
173	{
174	return 1UL & (((const volatile unsigned int *)addr)[nr>>5] >> (nr&31));
175	}
176
288a60cf	177	#if XCHAL_HAVE_NSA
9a8fd558 CZ	178
	179	static __inline__ int __cntlz (unsigned long x)
	180	{
	181	int lz;
	182	asm ("nsau %0, %1" : "=r" (lz) : "r" (x));
	183	return 31 - lz;
	184	}
	185
	186	#else
	187
	188	static __inline__ int __cntlz (unsigned long x)
	189	{
	190	unsigned long sum, x1, x2, x4, x8, x16;
	191	x1 = x & 0xAAAAAAAA;
	192	x2 = x & 0xCCCCCCCC;
	193	x4 = x & 0xF0F0F0F0;
	194	x8 = x & 0xFF00FF00;
	195	x16 = x & 0xFFFF0000;
	196	sum = x2 ? 2 : 0;
	197	sum += (x16 != 0) * 16;
	198	sum += (x8 != 0) * 8;
	199	sum += (x4 != 0) * 4;
	200	sum += (x1 != 0);
	201
	202	return sum;
	203	}
	204
	205	#endif
	206
	207	/*
	208	* ffz: Find first zero in word. Undefined if no zero exists.
	209	* bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
	210	*/
	211
	212	static __inline__ int ffz(unsigned long x)
	213	{
	214	if ((x = ~x) == 0)
	215	return 32;
	216	return __cntlz(x & -x);
	217	}
	218
	219	/*
	220	* __ffs: Find first bit set in word. Return 0 for bit 0
	221	*/
	222
	223	static __inline__ int __ffs(unsigned long x)
	224	{
	225	return __cntlz(x & -x);
	226	}
	227
	228	/*
	229	* ffs: Find first bit set in word. This is defined the same way as
	230	* the libc and compiler builtin ffs routines, therefore
	231	* differs in spirit from the above ffz (man ffs).
	232	*/
	233
	234	static __inline__ int ffs(unsigned long x)
	235	{
	236	return __cntlz(x & -x) + 1;
	237	}
	238
	239	/*
	240	* fls: Find last (most-significant) bit set in word.
	241	* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
242	*/
243
244	static __inline__ int fls (unsigned int x)
245	{
246	return __cntlz(x);
247	}
3821af2f	248	#define fls64(x) generic_fls64(x)
9a8fd558 CZ	249
	250	static __inline__ int
	251	find_next_bit(const unsigned long *addr, int size, int offset)
	252	{
	253	const unsigned long *p = addr + (offset >> 5);
	254	unsigned long result = offset & ~31UL;
	255	unsigned long tmp;
	256
	257	if (offset >= size)
	258	return size;
	259	size -= result;
	260	offset &= 31UL;
	261	if (offset) {
	262	tmp = *p++;
	263	tmp &= ~0UL << offset;
	264	if (size < 32)
	265	goto found_first;
	266	if (tmp)
	267	goto found_middle;
	268	size -= 32;
	269	result += 32;
	270	}
	271	while (size >= 32) {
	272	if ((tmp = *p++) != 0)
	273	goto found_middle;
	274	result += 32;
	275	size -= 32;
	276	}
	277	if (!size)
	278	return result;
	279	tmp = *p;
	280
	281	found_first:
	282	tmp &= ~0UL >> (32 - size);
	283	if (tmp == 0UL) /* Are any bits set? */
	284	return result + size; /* Nope. */
	285	found_middle:
	286	return result + __ffs(tmp);
	287	}
	288
	289	/**
	290	* find_first_bit - find the first set bit in a memory region
	291	* @addr: The address to start the search at
	292	* @size: The maximum size to search
	293	*
	294	* Returns the bit-number of the first set bit, not the number of the byte
	295	* containing a bit.
	296	*/
	297
	298	#define find_first_bit(addr, size) \
	299	find_next_bit((addr), (size), 0)
	300
	301	static __inline__ int
	302	find_next_zero_bit(const unsigned long *addr, int size, int offset)
	303	{
	304	const unsigned long *p = addr + (offset >> 5);
	305	unsigned long result = offset & ~31UL;
	306	unsigned long tmp;
	307
	308	if (offset >= size)
	309	return size;
	310	size -= result;
	311	offset &= 31UL;
	312	if (offset) {
313	tmp = *p++;
314	tmp \|= ~0UL >> (32-offset);
315	if (size < 32)
316	goto found_first;
317	if (~tmp)
318	goto found_middle;
319	size -= 32;
320	result += 32;
321	}
322	while (size & ~31UL) {
323	if (~(tmp = *p++))
324	goto found_middle;
325	result += 32;
326	size -= 32;
327	}
328	if (!size)
329	return result;
330	tmp = *p;
331
332	found_first:
333	tmp \|= ~0UL << size;
334	found_middle:
335	return result + ffz(tmp);
336	}
337
338	#define find_first_zero_bit(addr, size) \
339	find_next_zero_bit((addr), (size), 0)
340
341	#ifdef __XTENSA_EL__
342	# define ext2_set_bit(nr,addr) __test_and_set_bit((nr), (addr))
343	# define ext2_set_bit_atomic(lock,nr,addr) test_and_set_bit((nr),(addr))
344	# define ext2_clear_bit(nr,addr) __test_and_clear_bit((nr), (addr))
345	# define ext2_clear_bit_atomic(lock,nr,addr) test_and_clear_bit((nr),(addr))
346	# define ext2_test_bit(nr,addr) test_bit((nr), (addr))
347	# define ext2_find_first_zero_bit(addr, size) find_first_zero_bit((addr),(size))
348	# define ext2_find_next_zero_bit(addr, size, offset) \
349	find_next_zero_bit((addr), (size), (offset))
350	#elif defined(__XTENSA_EB__)
351	# define ext2_set_bit(nr,addr) __test_and_set_bit((nr) ^ 0x18, (addr))
352	# define ext2_set_bit_atomic(lock,nr,addr) test_and_set_bit((nr) ^ 0x18, (addr))
353	# define ext2_clear_bit(nr,addr) __test_and_clear_bit((nr) ^ 18, (addr))
354	# define ext2_clear_bit_atomic(lock,nr,addr) test_and_clear_bit((nr)^0x18,(addr))
355	# define ext2_test_bit(nr,addr) test_bit((nr) ^ 0x18, (addr))
356	# define ext2_find_first_zero_bit(addr, size) \
357	ext2_find_next_zero_bit((addr), (size), 0)
358
359	static __inline__ unsigned long ext2_find_next_zero_bit(void *addr, unsigned long size, unsigned long offset)
360	{
361	unsigned long p = ((unsigned long ) addr) + (offset >> 5);
362	unsigned long result = offset & ~31UL;
363	unsigned long tmp;
364
365	if (offset >= size)
366	return size;
367	size -= result;
368	offset &= 31UL;
369	if(offset) {
370	/* We hold the little endian value in tmp, but then the
371	* shift is illegal. So we could keep a big endian value
372	* in tmp, like this:
373	*
374	* tmp = __swab32(*(p++));
375	* tmp \|= ~0UL >> (32-offset);
376	*
377	* but this would decrease preformance, so we change the
378	* shift:
379	*/
380	tmp = *(p++);
381	tmp \|= __swab32(~0UL >> (32-offset));
382	if(size < 32)
383	goto found_first;
384	if(~tmp)
385	goto found_middle;
386	size -= 32;
387	result += 32;
388	}
389	while(size & ~31UL) {
390	if(~(tmp = *(p++)))
391	goto found_middle;
392	result += 32;
393	size -= 32;
394	}
395	if(!size)
396	return result;
397	tmp = *p;
398
399	found_first:
400	/* tmp is little endian, so we would have to swab the shift,
401	* see above. But then we have to swab tmp below for ffz, so
402	* we might as well do this here.
403	*/
404	return result + ffz(__swab32(tmp) \| (~0UL << size));
405	found_middle:
406	return result + ffz(__swab32(tmp));
407	}
408
409	#else
410	# error processor byte order undefined!
411	#endif
412
413
414	#define hweight32(x) generic_hweight32(x)
415	#define hweight16(x) generic_hweight16(x)
416	#define hweight8(x) generic_hweight8(x)
417
418	/*
419	* Find the first bit set in a 140-bit bitmap.
420	* The first 100 bits are unlikely to be set.
421	*/
422
423	static inline int sched_find_first_bit(const unsigned long *b)
424	{
425	if (unlikely(b[0]))
426	return __ffs(b[0]);
427	if (unlikely(b[1]))
428	return __ffs(b[1]) + 32;
429	if (unlikely(b[2]))
430	return __ffs(b[2]) + 64;
431	if (b[3])
432	return __ffs(b[3]) + 96;
433	return __ffs(b[4]) + 128;
434	}
435
436
437	/* Bitmap functions for the minix filesystem. */
438
439	#define minix_test_and_set_bit(nr,addr) test_and_set_bit(nr,addr)
440	#define minix_set_bit(nr,addr) set_bit(nr,addr)
441	#define minix_test_and_clear_bit(nr,addr) test_and_clear_bit(nr,addr)
442	#define minix_test_bit(nr,addr) test_bit(nr,addr)
443	#define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size)
444
445	#endif /* __KERNEL__ */
446
447	#endif /* _XTENSA_BITOPS_H */