include/asm-s390/bitops.h

#ifndef _S390_BITOPS_H
#define _S390_BITOPS_H

/*
 *  include/asm-s390/bitops.h
 *
 *  S390 version
 *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
 *
 *  Derived from "include/asm-i386/bitops.h"
 *    Copyright (C) 1992, Linus Torvalds
 *
 */
#include <linux/config.h>
#include <linux/compiler.h>

/*
 * 32 bit bitops format:
 * bit 0 is the LSB of *addr; bit 31 is the MSB of *addr;
 * bit 32 is the LSB of *(addr+4). That combined with the
 * big endian byte order on S390 give the following bit
 * order in memory:
 *    1f 1e 1d 1c 1b 1a 19 18 17 16 15 14 13 12 11 10 \
 *    0f 0e 0d 0c 0b 0a 09 08 07 06 05 04 03 02 01 00
 * after that follows the next long with bit numbers
 *    3f 3e 3d 3c 3b 3a 39 38 37 36 35 34 33 32 31 30
 *    2f 2e 2d 2c 2b 2a 29 28 27 26 25 24 23 22 21 20
 * The reason for this bit ordering is the fact that
 * in the architecture independent code bits operations
 * of the form "flags |= (1 << bitnr)" are used INTERMIXED
 * with operation of the form "set_bit(bitnr, flags)".
 *
 * 64 bit bitops format:
 * bit 0 is the LSB of *addr; bit 63 is the MSB of *addr;
 * bit 64 is the LSB of *(addr+8). That combined with the
 * big endian byte order on S390 give the following bit
 * order in memory:
 *    3f 3e 3d 3c 3b 3a 39 38 37 36 35 34 33 32 31 30
 *    2f 2e 2d 2c 2b 2a 29 28 27 26 25 24 23 22 21 20
 *    1f 1e 1d 1c 1b 1a 19 18 17 16 15 14 13 12 11 10
 *    0f 0e 0d 0c 0b 0a 09 08 07 06 05 04 03 02 01 00
 * after that follows the next long with bit numbers
 *    7f 7e 7d 7c 7b 7a 79 78 77 76 75 74 73 72 71 70
 *    6f 6e 6d 6c 6b 6a 69 68 67 66 65 64 63 62 61 60
 *    5f 5e 5d 5c 5b 5a 59 58 57 56 55 54 53 52 51 50
 *    4f 4e 4d 4c 4b 4a 49 48 47 46 45 44 43 42 41 40
 * The reason for this bit ordering is the fact that
 * in the architecture independent code bits operations
 * of the form "flags |= (1 << bitnr)" are used INTERMIXED
 * with operation of the form "set_bit(bitnr, flags)".
 */

/* set ALIGN_CS to 1 if the SMP safe bit operations should
 * align the address to 4 byte boundary. It seems to work
 * without the alignment. 
 */
#ifdef __KERNEL__
#define ALIGN_CS 0
#else
#define ALIGN_CS 1
#ifndef CONFIG_SMP
#error "bitops won't work without CONFIG_SMP"
#endif
#endif

/* bitmap tables from arch/S390/kernel/bitmap.S */
extern const char _oi_bitmap[];
extern const char _ni_bitmap[];
extern const char _zb_findmap[];
extern const char _sb_findmap[];

#ifndef __s390x__

#define __BITOPS_ALIGN		3
#define __BITOPS_WORDSIZE	32
#define __BITOPS_OR		"or"
#define __BITOPS_AND		"nr"
#define __BITOPS_XOR		"xr"

#define __BITOPS_LOOP(__old, __new, __addr, __val, __op_string)		\
	__asm__ __volatile__("   l   %0,0(%4)\n"			\
			     "0: lr  %1,%0\n"				\
			     __op_string "  %1,%3\n"			\
			     "   cs  %0,%1,0(%4)\n"			\
			     "   jl  0b"				\
			     : "=&d" (__old), "=&d" (__new),	       	\
			       "=m" (*(unsigned long *) __addr)		\
			     : "d" (__val), "a" (__addr),		\
			       "m" (*(unsigned long *) __addr) : "cc" );

#else /* __s390x__ */

#define __BITOPS_ALIGN		7
#define __BITOPS_WORDSIZE	64
#define __BITOPS_OR		"ogr"
#define __BITOPS_AND		"ngr"
#define __BITOPS_XOR		"xgr"

#define __BITOPS_LOOP(__old, __new, __addr, __val, __op_string)		\
	__asm__ __volatile__("   lg  %0,0(%4)\n"			\
			     "0: lgr %1,%0\n"				\
			     __op_string "  %1,%3\n"			\
			     "   csg %0,%1,0(%4)\n"			\
			     "   jl  0b"				\
			     : "=&d" (__old), "=&d" (__new),	       	\
			       "=m" (*(unsigned long *) __addr)		\
			     : "d" (__val), "a" (__addr),		\
			       "m" (*(unsigned long *) __addr) : "cc" );

#endif /* __s390x__ */

#define __BITOPS_WORDS(bits) (((bits)+__BITOPS_WORDSIZE-1)/__BITOPS_WORDSIZE)
#define __BITOPS_BARRIER() __asm__ __volatile__ ( "" : : : "memory" )

#ifdef CONFIG_SMP
/*
 * SMP safe set_bit routine based on compare and swap (CS)
 */
static inline void set_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
#if ALIGN_CS == 1
	nr += (addr & __BITOPS_ALIGN) << 3;    /* add alignment to bit number */
	addr ^= addr & __BITOPS_ALIGN;	       /* align address to 8 */
#endif
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make OR mask */
	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_OR);
}

/*
 * SMP safe clear_bit routine based on compare and swap (CS)
 */
static inline void clear_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
#if ALIGN_CS == 1
	nr += (addr & __BITOPS_ALIGN) << 3;    /* add alignment to bit number */
	addr ^= addr & __BITOPS_ALIGN;	       /* align address to 8 */
#endif
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make AND mask */
	mask = ~(1UL << (nr & (__BITOPS_WORDSIZE - 1)));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_AND);
}

/*
 * SMP safe change_bit routine based on compare and swap (CS)
 */
static inline void change_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
#if ALIGN_CS == 1
	nr += (addr & __BITOPS_ALIGN) << 3;    /* add alignment to bit number */
	addr ^= addr & __BITOPS_ALIGN;	       /* align address to 8 */
#endif
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make XOR mask */
	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_XOR);
}

/*
 * SMP safe test_and_set_bit routine based on compare and swap (CS)
 */
static inline int
test_and_set_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
#if ALIGN_CS == 1
	nr += (addr & __BITOPS_ALIGN) << 3;    /* add alignment to bit number */
	addr ^= addr & __BITOPS_ALIGN;	       /* align address to 8 */
#endif
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make OR/test mask */
	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_OR);
	__BITOPS_BARRIER();
	return (old & mask) != 0;
}

/*
 * SMP safe test_and_clear_bit routine based on compare and swap (CS)
 */
static inline int
test_and_clear_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
#if ALIGN_CS == 1
	nr += (addr & __BITOPS_ALIGN) << 3;    /* add alignment to bit number */
	addr ^= addr & __BITOPS_ALIGN;	       /* align address to 8 */
#endif
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make AND/test mask */
	mask = ~(1UL << (nr & (__BITOPS_WORDSIZE - 1)));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_AND);
	__BITOPS_BARRIER();
	return (old ^ new) != 0;
}

/*
 * SMP safe test_and_change_bit routine based on compare and swap (CS) 
 */
static inline int
test_and_change_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
#if ALIGN_CS == 1
	nr += (addr & __BITOPS_ALIGN) << 3;  /* add alignment to bit number */
	addr ^= addr & __BITOPS_ALIGN;	     /* align address to 8 */
#endif
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make XOR/test mask */
	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_XOR);
	__BITOPS_BARRIER();
	return (old & mask) != 0;
}
#endif /* CONFIG_SMP */

/*
 * fast, non-SMP set_bit routine
 */
static inline void __set_bit(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
        asm volatile("oc 0(1,%1),0(%2)"
		     : "=m" (*(char *) addr)
		     : "a" (addr), "a" (_oi_bitmap + (nr & 7)),
		       "m" (*(char *) addr) : "cc" );
}

static inline void 
__constant_set_bit(const unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;

	addr = ((unsigned long) ptr) + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	switch (nr&7) {
	case 0:
		asm volatile ("oi 0(%1),0x01" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 1:
		asm volatile ("oi 0(%1),0x02" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 2:
		asm volatile ("oi 0(%1),0x04" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 3:
		asm volatile ("oi 0(%1),0x08" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 4:
		asm volatile ("oi 0(%1),0x10" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 5:
		asm volatile ("oi 0(%1),0x20" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 6:
		asm volatile ("oi 0(%1),0x40" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 7:
		asm volatile ("oi 0(%1),0x80" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	}
}

#define set_bit_simple(nr,addr) \
(__builtin_constant_p((nr)) ? \
 __constant_set_bit((nr),(addr)) : \
 __set_bit((nr),(addr)) )

/*
 * fast, non-SMP clear_bit routine
 */
static inline void 
__clear_bit(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
        asm volatile("nc 0(1,%1),0(%2)"
		     : "=m" (*(char *) addr)
		     : "a" (addr), "a" (_ni_bitmap + (nr & 7)),
		       "m" (*(char *) addr) : "cc" );
}

static inline void 
__constant_clear_bit(const unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;

	addr = ((unsigned long) ptr) + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	switch (nr&7) {
	case 0:
		asm volatile ("ni 0(%1),0xFE" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 1:
		asm volatile ("ni 0(%1),0xFD": "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 2:
		asm volatile ("ni 0(%1),0xFB" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 3:
		asm volatile ("ni 0(%1),0xF7" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 4:
		asm volatile ("ni 0(%1),0xEF" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 5:
		asm volatile ("ni 0(%1),0xDF" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 6:
		asm volatile ("ni 0(%1),0xBF" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 7:
		asm volatile ("ni 0(%1),0x7F" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	}
}

#define clear_bit_simple(nr,addr) \
(__builtin_constant_p((nr)) ? \
 __constant_clear_bit((nr),(addr)) : \
 __clear_bit((nr),(addr)) )

/* 
 * fast, non-SMP change_bit routine 
 */
static inline void __change_bit(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
        asm volatile("xc 0(1,%1),0(%2)"
		     :  "=m" (*(char *) addr)
		     : "a" (addr), "a" (_oi_bitmap + (nr & 7)),
		       "m" (*(char *) addr) : "cc" );
}

static inline void 
__constant_change_bit(const unsigned long nr, volatile unsigned long *ptr) 
{
	unsigned long addr;

	addr = ((unsigned long) ptr) + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	switch (nr&7) {
	case 0:
		asm volatile ("xi 0(%1),0x01" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 1:
		asm volatile ("xi 0(%1),0x02" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 2:
		asm volatile ("xi 0(%1),0x04" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 3:
		asm volatile ("xi 0(%1),0x08" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 4:
		asm volatile ("xi 0(%1),0x10" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 5:
		asm volatile ("xi 0(%1),0x20" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 6:
		asm volatile ("xi 0(%1),0x40" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	case 7:
		asm volatile ("xi 0(%1),0x80" : "=m" (*(char *) addr)
			      : "a" (addr), "m" (*(char *) addr) : "cc" );
		break;
	}
}

#define change_bit_simple(nr,addr) \
(__builtin_constant_p((nr)) ? \
 __constant_change_bit((nr),(addr)) : \
 __change_bit((nr),(addr)) )

/*
 * fast, non-SMP test_and_set_bit routine
 */
static inline int
test_and_set_bit_simple(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;
	unsigned char ch;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	ch = *(unsigned char *) addr;
        asm volatile("oc 0(1,%1),0(%2)"
		     : "=m" (*(char *) addr)
		     : "a" (addr), "a" (_oi_bitmap + (nr & 7)),
		       "m" (*(char *) addr) : "cc", "memory" );
	return (ch >> (nr & 7)) & 1;
}
#define __test_and_set_bit(X,Y)		test_and_set_bit_simple(X,Y)

/*
 * fast, non-SMP test_and_clear_bit routine
 */
static inline int
test_and_clear_bit_simple(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;
	unsigned char ch;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	ch = *(unsigned char *) addr;
        asm volatile("nc 0(1,%1),0(%2)"
		     : "=m" (*(char *) addr)
		     : "a" (addr), "a" (_ni_bitmap + (nr & 7)),
		       "m" (*(char *) addr) : "cc", "memory" );
	return (ch >> (nr & 7)) & 1;
}
#define __test_and_clear_bit(X,Y)	test_and_clear_bit_simple(X,Y)

/*
 * fast, non-SMP test_and_change_bit routine
 */
static inline int
test_and_change_bit_simple(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;
	unsigned char ch;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	ch = *(unsigned char *) addr;
        asm volatile("xc 0(1,%1),0(%2)"
		     : "=m" (*(char *) addr)
		     : "a" (addr), "a" (_oi_bitmap + (nr & 7)),
		       "m" (*(char *) addr) : "cc", "memory" );
	return (ch >> (nr & 7)) & 1;
}
#define __test_and_change_bit(X,Y)	test_and_change_bit_simple(X,Y)

#ifdef CONFIG_SMP
#define set_bit             set_bit_cs
#define clear_bit           clear_bit_cs
#define change_bit          change_bit_cs
#define test_and_set_bit    test_and_set_bit_cs
#define test_and_clear_bit  test_and_clear_bit_cs
#define test_and_change_bit test_and_change_bit_cs
#else
#define set_bit             set_bit_simple
#define clear_bit           clear_bit_simple
#define change_bit          change_bit_simple
#define test_and_set_bit    test_and_set_bit_simple
#define test_and_clear_bit  test_and_clear_bit_simple
#define test_and_change_bit test_and_change_bit_simple
#endif


/*
 * This routine doesn't need to be atomic.
 */

static inline int __test_bit(unsigned long nr, const volatile unsigned long *ptr)
{
	unsigned long addr;
	unsigned char ch;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	ch = *(volatile unsigned char *) addr;
	return (ch >> (nr & 7)) & 1;
}

static inline int 
__constant_test_bit(unsigned long nr, const volatile unsigned long *addr) {
    return ((((volatile char *) addr)
	    [(nr^(__BITOPS_WORDSIZE-8))>>3] & (1<<(nr&7)))) != 0;
}

#define test_bit(nr,addr) \
(__builtin_constant_p((nr)) ? \
 __constant_test_bit((nr),(addr)) : \
 __test_bit((nr),(addr)) )

/*
 * ffz = Find First Zero in word. Undefined if no zero exists,
 * so code should check against ~0UL first..
 */
static inline unsigned long ffz(unsigned long word)
{
        unsigned long bit = 0;

#ifdef __s390x__
	if (likely((word & 0xffffffff) == 0xffffffff)) {
		word >>= 32;
		bit += 32;
	}
#endif
	if (likely((word & 0xffff) == 0xffff)) {
		word >>= 16;
		bit += 16;
	}
	if (likely((word & 0xff) == 0xff)) {
		word >>= 8;
		bit += 8;
	}
	return bit + _zb_findmap[word & 0xff];
}

/*
 * __ffs = find first bit in word. Undefined if no bit exists,
 * so code should check against 0UL first..
 */
static inline unsigned long __ffs (unsigned long word)
{
	unsigned long bit = 0;

#ifdef __s390x__
	if (likely((word & 0xffffffff) == 0)) {
		word >>= 32;
		bit += 32;
	}
#endif
	if (likely((word & 0xffff) == 0)) {
		word >>= 16;
		bit += 16;
	}
	if (likely((word & 0xff) == 0)) {
		word >>= 8;
		bit += 8;
	}
	return bit + _sb_findmap[word & 0xff];
}

/*
 * Find-bit routines..
 */

#ifndef __s390x__

static inline int
find_first_zero_bit(const unsigned long * addr, unsigned long size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
	unsigned long cmp, count;
        unsigned int res;

        if (!size)
                return 0;
        __asm__("   lhi  %1,-1\n"
                "   lr   %2,%3\n"
                "   slr  %0,%0\n"
                "   ahi  %2,31\n"
                "   srl  %2,5\n"
                "0: c    %1,0(%0,%4)\n"
                "   jne  1f\n"
                "   la   %0,4(%0)\n"
                "   brct %2,0b\n"
                "   lr   %0,%3\n"
                "   j    4f\n"
                "1: l    %2,0(%0,%4)\n"
                "   sll  %0,3\n"
                "   lhi  %1,0xff\n"
                "   tml  %2,0xffff\n"
                "   jno  2f\n"
                "   ahi  %0,16\n"
                "   srl  %2,16\n"
                "2: tml  %2,0x00ff\n"
                "   jno  3f\n"
                "   ahi  %0,8\n"
                "   srl  %2,8\n"
                "3: nr   %2,%1\n"
                "   ic   %2,0(%2,%5)\n"
                "   alr  %0,%2\n"
                "4:"
                : "=&a" (res), "=&d" (cmp), "=&a" (count)
                : "a" (size), "a" (addr), "a" (&_zb_findmap),
		  "m" (*(addrtype *) addr) : "cc" );
        return (res < size) ? res : size;
}

static inline int
find_first_bit(const unsigned long * addr, unsigned long size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
	unsigned long cmp, count;
        unsigned int res;

        if (!size)
                return 0;
        __asm__("   slr  %1,%1\n"
                "   lr   %2,%3\n"
                "   slr  %0,%0\n"
                "   ahi  %2,31\n"
                "   srl  %2,5\n"
                "0: c    %1,0(%0,%4)\n"
                "   jne  1f\n"
                "   la   %0,4(%0)\n"
                "   brct %2,0b\n"
                "   lr   %0,%3\n"
                "   j    4f\n"
                "1: l    %2,0(%0,%4)\n"
                "   sll  %0,3\n"
                "   lhi  %1,0xff\n"
                "   tml  %2,0xffff\n"
                "   jnz  2f\n"
                "   ahi  %0,16\n"
                "   srl  %2,16\n"
                "2: tml  %2,0x00ff\n"
                "   jnz  3f\n"
                "   ahi  %0,8\n"
                "   srl  %2,8\n"
                "3: nr   %2,%1\n"
                "   ic   %2,0(%2,%5)\n"
                "   alr  %0,%2\n"
                "4:"
                : "=&a" (res), "=&d" (cmp), "=&a" (count)
                : "a" (size), "a" (addr), "a" (&_sb_findmap),
		  "m" (*(addrtype *) addr) : "cc" );
        return (res < size) ? res : size;
}

#else /* __s390x__ */

static inline unsigned long
find_first_zero_bit(const unsigned long * addr, unsigned long size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
        unsigned long res, cmp, count;

        if (!size)
                return 0;
        __asm__("   lghi  %1,-1\n"
                "   lgr   %2,%3\n"
                "   slgr  %0,%0\n"
                "   aghi  %2,63\n"
                "   srlg  %2,%2,6\n"
                "0: cg    %1,0(%0,%4)\n"
                "   jne   1f\n"
                "   la    %0,8(%0)\n"
                "   brct  %2,0b\n"
                "   lgr   %0,%3\n"
                "   j     5f\n"
                "1: lg    %2,0(%0,%4)\n"
                "   sllg  %0,%0,3\n"
                "   clr   %2,%1\n"
		"   jne   2f\n"
		"   aghi  %0,32\n"
                "   srlg  %2,%2,32\n"
		"2: lghi  %1,0xff\n"
                "   tmll  %2,0xffff\n"
                "   jno   3f\n"
                "   aghi  %0,16\n"
                "   srl   %2,16\n"
                "3: tmll  %2,0x00ff\n"
                "   jno   4f\n"
                "   aghi  %0,8\n"
                "   srl   %2,8\n"
                "4: ngr   %2,%1\n"
                "   ic    %2,0(%2,%5)\n"
                "   algr  %0,%2\n"
                "5:"
                : "=&a" (res), "=&d" (cmp), "=&a" (count)
		: "a" (size), "a" (addr), "a" (&_zb_findmap),
		  "m" (*(addrtype *) addr) : "cc" );
        return (res < size) ? res : size;
}

static inline unsigned long
find_first_bit(const unsigned long * addr, unsigned long size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
        unsigned long res, cmp, count;

        if (!size)
                return 0;
        __asm__("   slgr  %1,%1\n"
                "   lgr   %2,%3\n"
                "   slgr  %0,%0\n"
                "   aghi  %2,63\n"
                "   srlg  %2,%2,6\n"
                "0: cg    %1,0(%0,%4)\n"
                "   jne   1f\n"
                "   aghi  %0,8\n"
                "   brct  %2,0b\n"
                "   lgr   %0,%3\n"
                "   j     5f\n"
                "1: lg    %2,0(%0,%4)\n"
                "   sllg  %0,%0,3\n"
                "   clr   %2,%1\n"
		"   jne   2f\n"
		"   aghi  %0,32\n"
                "   srlg  %2,%2,32\n"
		"2: lghi  %1,0xff\n"
                "   tmll  %2,0xffff\n"
                "   jnz   3f\n"
                "   aghi  %0,16\n"
                "   srl   %2,16\n"
                "3: tmll  %2,0x00ff\n"
                "   jnz   4f\n"
                "   aghi  %0,8\n"
                "   srl   %2,8\n"
                "4: ngr   %2,%1\n"
                "   ic    %2,0(%2,%5)\n"
                "   algr  %0,%2\n"
                "5:"
                : "=&a" (res), "=&d" (cmp), "=&a" (count)
		: "a" (size), "a" (addr), "a" (&_sb_findmap),
		  "m" (*(addrtype *) addr) : "cc" );
        return (res < size) ? res : size;
}

#endif /* __s390x__ */

static inline int
find_next_zero_bit (const unsigned long * addr, unsigned long size,
		    unsigned long offset)
{
        const unsigned long *p;
	unsigned long bit, set;

	if (offset >= size)
		return size;
	bit = offset & (__BITOPS_WORDSIZE - 1);
	offset -= bit;
	size -= offset;
	p = addr + offset / __BITOPS_WORDSIZE;
	if (bit) {
		/*
		 * s390 version of ffz returns __BITOPS_WORDSIZE
		 * if no zero bit is present in the word.
		 */
		set = ffz(*p >> bit) + bit;
		if (set >= size)
			return size + offset;
		if (set < __BITOPS_WORDSIZE)
			return set + offset;
		offset += __BITOPS_WORDSIZE;
		size -= __BITOPS_WORDSIZE;
		p++;
	}
	return offset + find_first_zero_bit(p, size);
}

static inline int
find_next_bit (const unsigned long * addr, unsigned long size,
	       unsigned long offset)
{
        const unsigned long *p;
	unsigned long bit, set;

	if (offset >= size)
		return size;
	bit = offset & (__BITOPS_WORDSIZE - 1);
	offset -= bit;
	size -= offset;
	p = addr + offset / __BITOPS_WORDSIZE;
	if (bit) {
		/*
		 * s390 version of __ffs returns __BITOPS_WORDSIZE
		 * if no one bit is present in the word.
		 */
		set = __ffs(*p & (~0UL << bit));
		if (set >= size)
			return size + offset;
		if (set < __BITOPS_WORDSIZE)
			return set + offset;
		offset += __BITOPS_WORDSIZE;
		size -= __BITOPS_WORDSIZE;
		p++;
	}
	return offset + find_first_bit(p, size);
}

/*
 * 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(unsigned long *b)
{
	return find_first_bit(b, 140);
}

/*
 * 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 ffz (man ffs).
 */
#define ffs(x) generic_ffs(x)

/*
 * fls: find last bit set.
 */
#define fls(x) generic_fls(x)

/*
 * hweightN: returns the hamming weight (i.e. the number
 * of bits set) of a N-bit word
 */
#define hweight64(x)						\
({								\
	unsigned long __x = (x);				\
	unsigned int __w;					\
	__w = generic_hweight32((unsigned int) __x);		\
	__w += generic_hweight32((unsigned int) (__x>>32));	\
	__w;							\
})
#define hweight32(x) generic_hweight32(x)
#define hweight16(x) generic_hweight16(x)
#define hweight8(x) generic_hweight8(x)


#ifdef __KERNEL__

/*
 * ATTENTION: intel byte ordering convention for ext2 and minix !!
 * bit 0 is the LSB of addr; bit 31 is the MSB of addr;
 * bit 32 is the LSB of (addr+4).
 * That combined with the little endian byte order of Intel gives the
 * following bit order in memory:
 *    07 06 05 04 03 02 01 00 15 14 13 12 11 10 09 08 \
 *    23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24
 */

#define ext2_set_bit(nr, addr)       \
	test_and_set_bit((nr)^(__BITOPS_WORDSIZE - 8), (unsigned long *)addr)
#define ext2_set_bit_atomic(lock, nr, addr)       \
	test_and_set_bit((nr)^(__BITOPS_WORDSIZE - 8), (unsigned long *)addr)
#define ext2_clear_bit(nr, addr)     \
	test_and_clear_bit((nr)^(__BITOPS_WORDSIZE - 8), (unsigned long *)addr)
#define ext2_clear_bit_atomic(lock, nr, addr)     \
	test_and_clear_bit((nr)^(__BITOPS_WORDSIZE - 8), (unsigned long *)addr)
#define ext2_test_bit(nr, addr)      \
	test_bit((nr)^(__BITOPS_WORDSIZE - 8), (unsigned long *)addr)

#ifndef __s390x__

static inline int 
ext2_find_first_zero_bit(void *vaddr, unsigned int size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
	unsigned long cmp, count;
        unsigned int res;

        if (!size)
                return 0;
        __asm__("   lhi  %1,-1\n"
                "   lr   %2,%3\n"
                "   ahi  %2,31\n"
                "   srl  %2,5\n"
                "   slr  %0,%0\n"
                "0: cl   %1,0(%0,%4)\n"
                "   jne  1f\n"
                "   ahi  %0,4\n"
                "   brct %2,0b\n"
                "   lr   %0,%3\n"
                "   j    4f\n"
                "1: l    %2,0(%0,%4)\n"
                "   sll  %0,3\n"
                "   ahi  %0,24\n"
                "   lhi  %1,0xff\n"
                "   tmh  %2,0xffff\n"
                "   jo   2f\n"
                "   ahi  %0,-16\n"
                "   srl  %2,16\n"
                "2: tml  %2,0xff00\n"
                "   jo   3f\n"
                "   ahi  %0,-8\n"
                "   srl  %2,8\n"
                "3: nr   %2,%1\n"
                "   ic   %2,0(%2,%5)\n"
                "   alr  %0,%2\n"
                "4:"
                : "=&a" (res), "=&d" (cmp), "=&a" (count)
                : "a" (size), "a" (vaddr), "a" (&_zb_findmap),
		  "m" (*(addrtype *) vaddr) : "cc" );
        return (res < size) ? res : size;
}

#else /* __s390x__ */

static inline unsigned long
ext2_find_first_zero_bit(void *vaddr, unsigned long size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
        unsigned long res, cmp, count;

        if (!size)
                return 0;
        __asm__("   lghi  %1,-1\n"
                "   lgr   %2,%3\n"
                "   aghi  %2,63\n"
                "   srlg  %2,%2,6\n"
                "   slgr  %0,%0\n"
                "0: clg   %1,0(%0,%4)\n"
                "   jne   1f\n"
                "   aghi  %0,8\n"
                "   brct  %2,0b\n"
                "   lgr   %0,%3\n"
                "   j     5f\n"
                "1: cl    %1,0(%0,%4)\n"
		"   jne   2f\n"
		"   aghi  %0,4\n"
		"2: l     %2,0(%0,%4)\n"
                "   sllg  %0,%0,3\n"
                "   aghi  %0,24\n"
                "   lghi  %1,0xff\n"
                "   tmlh  %2,0xffff\n"
                "   jo    3f\n"
                "   aghi  %0,-16\n"
                "   srl   %2,16\n"
                "3: tmll  %2,0xff00\n"
                "   jo    4f\n"
                "   aghi  %0,-8\n"
                "   srl   %2,8\n"
                "4: ngr   %2,%1\n"
                "   ic    %2,0(%2,%5)\n"
                "   algr  %0,%2\n"
                "5:"
                : "=&a" (res), "=&d" (cmp), "=&a" (count)
		: "a" (size), "a" (vaddr), "a" (&_zb_findmap),
		  "m" (*(addrtype *) vaddr) : "cc" );
        return (res < size) ? res : size;
}

#endif /* __s390x__ */

static inline int
ext2_find_next_zero_bit(void *vaddr, unsigned long size, unsigned long offset)
{
        unsigned long *addr = vaddr, *p;
	unsigned long word, bit, set;

        if (offset >= size)
                return size;
	bit = offset & (__BITOPS_WORDSIZE - 1);
	offset -= bit;
	size -= offset;
	p = addr + offset / __BITOPS_WORDSIZE;
        if (bit) {
#ifndef __s390x__
                asm("   ic   %0,0(%1)\n"
		    "   icm  %0,2,1(%1)\n"
		    "   icm  %0,4,2(%1)\n"
		    "   icm  %0,8,3(%1)"
		    : "=&a" (word) : "a" (p), "m" (*p) : "cc" );
#else
                asm("   lrvg %0,%1" : "=a" (word) : "m" (*p) );
#endif
		/*
		 * s390 version of ffz returns __BITOPS_WORDSIZE
		 * if no zero bit is present in the word.
		 */
		set = ffz(word >> bit) + bit;
		if (set >= size)
			return size + offset;
		if (set < __BITOPS_WORDSIZE)
			return set + offset;
		offset += __BITOPS_WORDSIZE;
		size -= __BITOPS_WORDSIZE;
		p++;
        }
	return offset + ext2_find_first_zero_bit(p, size);
}

/* Bitmap functions for the minix filesystem.  */
/* FIXME !!! */
#define minix_test_and_set_bit(nr,addr) \
	test_and_set_bit(nr,(unsigned long *)addr)
#define minix_set_bit(nr,addr) \
	set_bit(nr,(unsigned long *)addr)
#define minix_test_and_clear_bit(nr,addr) \
	test_and_clear_bit(nr,(unsigned long *)addr)
#define minix_test_bit(nr,addr) \
	test_bit(nr,(unsigned long *)addr)
#define minix_find_first_zero_bit(addr,size) \
	find_first_zero_bit(addr,size)

#endif /* __KERNEL__ */

#endif /* _S390_BITOPS_H */