#ifndef _I386_BITOPS_H
#define _I386_BITOPS_H

/*
 * Copyright 1992, Linus Torvalds.
 */

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

/*
 * 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.
 *
 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
 */

#ifdef CONFIG_SMP
#define LOCK_PREFIX "lock ; "
#else
#define LOCK_PREFIX ""
#endif

#define ADDR (*(volatile long *) addr)

/**
 * 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: there are no guarantees that this function will not be reordered
 * on non x86 architectures, so if you are writting portable code,
 * make sure not to rely on its reordering 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(int nr, volatile unsigned long *addr)
{
    __asm__ __volatile__(LOCK_PREFIX "btsl %1,%0":"=m"(ADDR):"Ir"(nr));
}

/**
 * __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(int nr, volatile unsigned long *addr)
{
  __asm__("btsl %1,%0": "=m"(ADDR):"Ir"(nr));
}

/**
 * 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(int nr, volatile unsigned long *addr)
{
    __asm__ __volatile__(LOCK_PREFIX "btrl %1,%0":"=m"(ADDR):"Ir"(nr));
}

static inline void
__clear_bit(int nr, volatile unsigned long *addr)
{
    __asm__ __volatile__("btrl %1,%0":"=m"(ADDR):"Ir"(nr));
}

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

/**
 * __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(int nr, volatile unsigned long *addr)
{
    __asm__ __volatile__("btcl %1,%0":"=m"(ADDR):"Ir"(nr));
}

/**
 * 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. It may be
 * reordered on other architectures than x86.
 * 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(int nr, volatile unsigned long *addr)
{
    __asm__ __volatile__(LOCK_PREFIX "btcl %1,%0":"=m"(ADDR):"Ir"(nr));
}

/**
 * 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 may be reordered on other architectures than x86.
 * It also implies a memory barrier.
 */
static inline int
test_and_set_bit(int nr, volatile unsigned long *addr)
{
    int oldbit;

    __asm__ __volatile__(LOCK_PREFIX
			 "btsl %2,%1\n\tsbbl %0,%0":"=r"(oldbit),
			 "=m"(ADDR):"Ir"(nr):"memory");
    return oldbit;
}

/**
 * __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(int nr, volatile unsigned long *addr)
{
    int oldbit;

  __asm__("btsl %2,%1\n\tsbbl %0,%0": "=r"(oldbit), "=m"(ADDR):"Ir"(nr));
    return oldbit;
}

/**
 * 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 can be reorderdered on other architectures other than x86.
 * It also implies a memory barrier.
 */
static inline int
test_and_clear_bit(int nr, volatile unsigned long *addr)
{
    int oldbit;

    __asm__ __volatile__(LOCK_PREFIX
			 "btrl %2,%1\n\tsbbl %0,%0":"=r"(oldbit),
			 "=m"(ADDR):"Ir"(nr):"memory");
    return oldbit;
}

/**
 * __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(int nr, volatile unsigned long *addr)
{
    int oldbit;

  __asm__("btrl %2,%1\n\tsbbl %0,%0": "=r"(oldbit), "=m"(ADDR):"Ir"(nr));
    return oldbit;
}

/* WARNING: non atomic and it can be reordered! */
static inline int
__test_and_change_bit(int nr, volatile unsigned long *addr)
{
    int oldbit;

    __asm__ __volatile__("btcl %2,%1\n\tsbbl %0,%0":"=r"(oldbit),
			 "=m"(ADDR):"Ir"(nr):"memory");
    return oldbit;
}

/**
 * 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(int nr, volatile unsigned long *addr)
{
    int oldbit;

    __asm__ __volatile__(LOCK_PREFIX
			 "btcl %2,%1\n\tsbbl %0,%0":"=r"(oldbit),
			 "=m"(ADDR):"Ir"(nr):"memory");
    return oldbit;
}

#if 0				/* Fool kernel-doc since it doesn't do macros yet */
/**
 * test_bit - Determine whether a bit is set
 * @nr: bit number to test
 * @addr: Address to start counting from
 */
static int test_bit(int nr, const volatile void *addr);
#endif

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

static inline int
variable_test_bit(int nr, const volatile unsigned long *addr)
{
    int oldbit;

    __asm__ __volatile__("btl %2,%1\n\tsbbl %0,%0":"=r"(oldbit):"m"(ADDR),
			 "Ir"(nr));
    return oldbit;
}

#define test_bit(nr,addr) \
(__builtin_constant_p(nr) ? \
constant_test_bit((nr),(addr)) : \
variable_test_bit((nr),(addr)))

#undef ADDR

/**
 * find_first_zero_bit - find the first zero 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 zero bit, not the number of the byte
 * containing a bit.
 */
static inline int
find_first_zero_bit(const unsigned long *addr, unsigned size)
{
    int d0, d1, d2;
    int res;

    if (!size)
	return 0;
    /* This looks at memory. Mark it volatile to tell gcc not to move it around */
    __asm__ __volatile__("movl $-1,%%eax\n\t"
			 "xorl %%edx,%%edx\n\t"
			 "repe; scasl\n\t"
			 "je 1f\n\t"
			 "xorl -4(%%edi),%%eax\n\t"
			 "subl $4,%%edi\n\t"
			 "bsfl %%eax,%%edx\n"
			 "1:\tsubl %%ebx,%%edi\n\t"
			 "shll $3,%%edi\n\t"
			 "addl %%edi,%%edx":"=d"(res), "=&c"(d0), "=&D"(d1),
			 "=&a"(d2):"1"((size + 31) >> 5), "2"(addr),
			 "b"(addr):"memory");
    return res;
}

/**
 * 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
 */
int find_next_zero_bit(const unsigned long *addr, int size, int offset);

/**
 * __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)
{
  __asm__("bsfl %1,%0": "=r"(word):"rm"(word));
    return word;
}

/**
 * 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.
 */
static inline int
find_first_bit(const unsigned long *addr, unsigned size)
{
    int x = 0;

    while (x < size) {
	unsigned long val = *addr++;
	if (val)
	    return __ffs(val) + x;
	x += (sizeof(*addr) << 3);
    }
    return x;
}

/**
 * find_next_bit - find the first 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
 */
int find_next_bit(const unsigned long *addr, int size, int offset);

/**
 * 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)
{
  __asm__("bsfl %1,%0": "=r"(word):"r"(~word));
    return word;
}

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

#define fls(x) generic_fls(x)

#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)
{
    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;
}

/**
 * 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).
 */
static inline int
ffs(int x)
{
    int r;

  __asm__("bsfl %1,%0\n\t" "jnz 1f\n\t" "movl $-1,%0\n" "1:": "=r"(r):"rm"(x));
    return r + 1;
}

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

#ifdef __KERNEL__

#define ext2_set_bit(nr,addr) \
__test_and_set_bit((nr),(unsigned long*)addr)
#define ext2_set_bit_atomic(lock,nr,addr) \
test_and_set_bit((nr),(unsigned long*)addr)
#define ext2_clear_bit(nr, addr) \
__test_and_clear_bit((nr),(unsigned long*)addr)
#define ext2_clear_bit_atomic(lock,nr, addr) \
test_and_clear_bit((nr),(unsigned long*)addr)
#define ext2_test_bit(nr, addr)      test_bit((nr),(unsigned long*)addr)
#define ext2_find_first_zero_bit(addr, size) \
find_first_zero_bit((unsigned long*)addr, size)
#define ext2_find_next_zero_bit(addr, size, off) \
find_next_zero_bit((unsigned long*)addr, size, off)

/* Bitmap functions for the minix filesystem.  */
#define minix_test_and_set_bit(nr,addr) __test_and_set_bit(nr,(void*)addr)
#define minix_set_bit(nr,addr) __set_bit(nr,(void*)addr)
#define minix_test_and_clear_bit(nr,addr) __test_and_clear_bit(nr,(void*)addr)
#define minix_test_bit(nr,addr) test_bit(nr,(void*)addr)
#define minix_find_first_zero_bit(addr,size) \
find_first_zero_bit((void*)addr,size)
#endif /* __KERNEL__ */
#endif /* _I386_BITOPS_H */
