bitops.h

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                          : "=m" (*((volatile char *) addr + ((nr>>3)^3)))
                          : : "cc", "memory" );
    break;
  case 3:
    __asm__ __volatile__ ("la 1,%0\n\t"
                          "xi 0(1),0x08"
                          : "=m" (*((volatile char *) addr + ((nr>>3)^3)))
                          : : "cc", "memory" );
    break;
  case 4:
    __asm__ __volatile__ ("la 1,%0\n\t"
                          "xi 0(1),0x10"
                          : "=m" (*((volatile char *) addr + ((nr>>3)^3)))
                          : : "cc", "memory" );
    break;
  case 5:
    __asm__ __volatile__ ("la 1,%0\n\t"
                          "xi 0(1),0x20"
                          : "=m" (*((volatile char *) addr + ((nr>>3)^3)))
                          : : "1", "cc", "memory" );
    break;
  case 6:
    __asm__ __volatile__ ("la 1,%0\n\t"
                          "xi 0(1),0x40"
                          : "=m" (*((volatile char *) addr + ((nr>>3)^3)))
                          : : "1", "cc", "memory" );
    break;
  case 7:
    __asm__ __volatile__ ("la 1,%0\n\t"
                          "xi 0(1),0x80"
                          : "=m" (*((volatile char *) addr + ((nr>>3)^3)))
                          : : "1", "cc", "memory" );
    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
 */
extern __inline__ int test_and_set_bit_simple(int nr, volatile void * addr)
{
        static const int mask = 1;
        int oldbit;
        __asm__ __volatile__(
             "   lhi   1,24\n"
             "   lhi   2,7\n"
             "   xr    1,%1\n"
             "   nr    2,1\n"
             "   srl   1,3(0)\n"
             "   la    1,0(1,%2)\n"
             "   ic    %0,0(0,1)\n"
             "   srl   %0,0(2)\n"
             "   n     %0,%4\n"
             "   la    2,0(2,%3)\n"
             "   oc    0(1,1),0(2)"
             : "=d&" (oldbit) : "r" (nr), "a" (addr),
               "a" (&_oi_bitmap), "m" (mask)
             : "cc", "memory", "1", "2" );
        return oldbit;
}

/*
 * fast, non-SMP test_and_clear_bit routine
 */
extern __inline__ int test_and_clear_bit_simple(int nr, volatile void * addr)
{
        static const int mask = 1;
        int oldbit;

        __asm__ __volatile__(
             "   lhi   1,24\n"
             "   lhi   2,7\n"
             "   xr    1,%1\n"
             "   nr    2,1\n"
             "   srl   1,3(0)\n"
             "   la    1,0(1,%2)\n"
             "   ic    %0,0(0,1)\n"
             "   srl   %0,0(2)\n"
             "   n     %0,%4\n"
             "   la    2,0(2,%3)\n"
             "   nc    0(1,1),0(2)"
             : "=d&" (oldbit) : "r" (nr), "a" (addr),
               "a" (&_ni_bitmap), "m" (mask)
             : "cc", "memory", "1", "2" );
        return oldbit;
}

/*
 * fast, non-SMP test_and_change_bit routine
 */
extern __inline__ int test_and_change_bit_simple(int nr, volatile void * addr)
{
        static const int mask = 1;
        int oldbit;

        __asm__ __volatile__(
             "   lhi   1,24\n"
             "   lhi   2,7\n"
             "   xr    1,%1\n"
             "   nr    2,1\n"
             "   srl   1,3(0)\n"
             "   la    1,0(1,%2)\n"
             "   ic    %0,0(0,1)\n"
             "   srl   %0,0(2)\n"
             "   n     %0,%4\n"
             "   la    2,0(2,%3)\n"
             "   xc    0(1,1),0(2)"
             : "=d&" (oldbit) : "r" (nr), "a" (addr),
               "a" (&_oi_bitmap), "m" (mask)
             : "cc", "memory", "1", "2" );
        return oldbit;
}

#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.
 */

extern __inline__ int __test_bit(int nr, volatile void * addr)
{
        static const int mask = 1;
        int oldbit;

        __asm__ __volatile__(
             "   lhi   2,24\n"
             "   lhi   1,7\n"
             "   xr    2,%1\n"
             "   nr    1,%1\n"
             "   srl   2,3\n"
             "   ic    %0,0(2,%2)\n"
             "   srl   %0,0(1)\n"
             "   n     %0,%3"
             : "=d&" (oldbit) : "r" (nr), "a" (addr),
               "m" (mask)
             : "cc", "1", "2" );
        return oldbit;
}

extern __inline__ int __constant_test_bit(int nr, volatile void * addr) {
    return (((volatile char *) addr)[(nr>>3)^3] & (1<<(nr&7))) != 0;
}

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

/*
 * Find-bit routines..
 */
extern __inline__ int find_first_zero_bit(void * addr, unsigned size)
{
        static const int mask = 0xffL;
        int res;

        if (!size)
                return 0;
        __asm__("   lhi  0,-1\n"
                "   lr   1,%1\n"
                "   ahi  1,31\n"
                "   srl  1,5\n"
                "   sr   2,2\n"
                "0: c    0,0(2,%2)\n"
                "   jne  1f\n"
                "   ahi  2,4\n"
                "   brct 1,0b\n"
                "   lr   2,%1\n"
                "   j    4f\n"
                "1: l    1,0(2,%2)\n"
                "   sll  2,3(0)\n"
                "   tml  1,0xFFFF\n"
                "   jno  2f\n"
                "   ahi  2,16\n"
                "   srl  1,16\n"
                "2: tml  1,0x00FF\n"
                "   jno  3f\n"
                "   ahi  2,8\n"
                "   srl  1,8\n"
                "3: n    1,%3\n"
                "   ic   1,0(1,%4)\n"
                "   n    1,%3\n"
                "   ar   2,1\n"
                "4: lr   %0,2"
                : "=d" (res) : "a" (size), "a" (addr),
                  "m" (mask), "a" (&_zb_findmap)
                : "cc", "0", "1", "2" );
        return (res < size) ? res : size;
}

extern __inline__ int find_next_zero_bit (void * addr, int size, int offset)
{
        static const int mask = 0xffL;
        unsigned long * p = ((unsigned long *) addr) + (offset >> 5);
        unsigned long bitvec;
        int set, bit = offset & 31, res;

        if (bit) {
                /*
                 * Look for zero in first word
                 */
                bitvec = (*p) >> bit;
                __asm__("   lr   1,%1\n"
                        "   sr   %0,%0\n"
                        "   tml  1,0xFFFF\n"
                        "   jno  0f\n"
                        "   ahi  %0,16\n"
                        "   srl  1,16\n"
                        "0: tml  1,0x00FF\n"
                        "   jno  1f\n"
                        "   ahi  %0,8\n"
                        "   srl  1,8\n"
                        "1: n    1,%2\n"
                        "   ic   1,0(1,%3)\n"
                        "   n    1,%2\n"
                        "   ar   %0,1"
                        : "=d&" (set) : "d" (bitvec),
                          "m" (mask), "a" (&_zb_findmap)
                          : "cc", "1" );
                if (set < (32 - bit))
                        return set + offset;
                offset += 32 - bit;
                p++;
        }
        /*
         * No zero yet, search remaining full words for a zero
         */
        res = find_first_zero_bit (p, size - 32 * (p - (unsigned long *) addr));
        return (offset + res);
}

/*
 * ffz = Find First Zero in word. Undefined if no zero exists,
 * so code should check against ~0UL first..
 */
extern __inline__ unsigned long ffz(unsigned long word)
{
        static const int mask = 0xffL;
        int result;

        __asm__("   lr   1,%1\n"
                "   sr   %0,%0\n"
                "   tml  1,0xFFFF\n"
                "   jno  0f\n"
                "   ahi  %0,16\n"
                "   srl  1,16\n"
                "0: tml  1,0x00FF\n"
                "   jno  1f\n"
                "   ahi  %0,8\n"
                "   srl  1,8\n"
                "1: n    1,%2\n"
                "   ic   1,0(1,%3)\n"
                "   n    1,%2\n"
                "   ar   %0,1"
                : "=d&" (result) : "d" (word), 
                  "m" (mask), "a" (&_zb_findmap)
                : "cc", "1" );

        return result;
}

/*
 * 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).
 */

extern int __inline__ ffs (int x)
{
        int r;

        if (x == 0)
          return 0;
        __asm__("    lr   %%r1,%1\n"
                "    sr   %0,%0\n"
                "    tmh  %%r1,0xFFFF\n"
                "    jz   0f\n"
                "    ahi  %0,16\n"
                "    srl  %%r1,16\n"
                "0:  tml  %%r1,0xFF00\n"
                "    jz   1f\n"
                "    ahi  %0,8\n"
                "    srl  %%r1,8\n"
                "1:  tml  %%r1,0x00F0\n"
                "    jz   2f\n"
                "    ahi  %0,4\n"
                "    srl  %%r1,4\n"
                "2:  tml  %%r1,0x000C\n"
                "    jz   3f\n"
                "    ahi  %0,2\n"
                "    srl  %%r1,2\n"
                "3:  tml  %%r1,0x0002\n"
                "    jz   4f\n"
                "    ahi  %0,1\n"
                "4:"
                : "=&d" (r) : "d" (x) : "cc", "1" );
        return r+1;
}

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

#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)^24, addr)
#define ext2_clear_bit(nr, addr)     test_and_clear_bit((nr)^24, addr)
#define ext2_test_bit(nr, addr)      test_bit((nr)^24, addr)
extern __inline__ int ext2_find_first_zero_bit(void *vaddr, unsigned size)
{
        static const int mask = 0xffL;
        int res;

        if (!size)
                return 0;
        __asm__("   lhi  0,-1\n"
                "   lr   1,%1\n"
                "   ahi  1,31\n"
                "   srl  1,5\n"
                "   sr   2,2\n"
                "0: c    0,0(2,%2)\n"
                "   jne  1f\n"
                "   ahi  2,4\n"
                "   brct 1,0b\n"
                "   lr   2,%1\n"
                "   j    4f\n"
                "1: l    1,0(2,%2)\n"
                "   sll  2,3(0)\n"
                "   ahi  2,24\n"
                "   tmh  1,0xFFFF\n"
                "   jo   2f\n"
                "   ahi  2,-16\n"
                "   srl  1,16\n"
                "2: tml  1,0xFF00\n"
                "   jo   3f\n"
                "   ahi  2,-8\n"
                "   srl  1,8\n"
                "3: n    1,%3\n"
                "   ic   1,0(1,%4)\n"
                "   n    1,%3\n"
                "   ar   2,1\n"
                "4: lr   %0,2"
                : "=d" (res) : "a" (size), "a" (vaddr),
                  "m" (mask), "a" (&_zb_findmap)
                  : "cc", "0", "1", "2" );
        return (res < size) ? res : size;
}

extern __inline__ int 
ext2_find_next_zero_bit(void *vaddr, unsigned size, unsigned offset)
{
        static const int mask = 0xffL;
        static unsigned long orword[32] = {
		0x00000000, 0x01000000, 0x03000000, 0x07000000,
		0x0f000000, 0x1f000000, 0x3f000000, 0x7f000000,
		0xff000000, 0xff010000, 0xff030000, 0xff070000,
                0xff0f0000, 0xff1f0000, 0xff3f0000, 0xff7f0000,
		0xffff0000, 0xffff0100, 0xffff0300, 0xffff0700,
		0xffff0f00, 0xffff1f00, 0xffff3f00, 0xffff7f00,
		0xffffff00, 0xffffff01, 0xffffff03, 0xffffff07,
		0xffffff0f, 0xffffff1f, 0xffffff3f, 0xffffff7f
	};
        unsigned long *addr = vaddr;
        unsigned long *p = addr + (offset >> 5);
        unsigned long word;
        int bit = offset & 31UL, res;

        if (offset >= size)
                return size;

        if (bit) {
		word = *p | orword[bit];
                /* Look for zero in first longword */
                __asm__("   lhi  %0,24\n"
                	"   tmh  %1,0xFFFF\n"
                	"   jo   0f\n"
                	"   ahi  %0,-16\n"
                	"   srl  %1,16\n"
                	"0: tml  %1,0xFF00\n"
                	"   jo   1f\n"
                	"   ahi  %0,-8\n"
                	"   srl  %1,8\n"
                	"1: n    %1,%2\n"
                	"   ic   %1,0(%1,%3)\n"
                	"   alr  %0,%1"
                	: "=&d" (res), "+&d" (word)
                  	: "m" (mask), "a" (&_zb_findmap)
                	: "cc" );
                if (res < 32)
			return (p - addr)*32 + res;
                p++;
        }
        /* No zero yet, search remaining full bytes for a zero */
        res = ext2_find_first_zero_bit (p, size - 32 * (p - addr));
        return (p - addr) * 32 + res;
}

/* Bitmap functions for the minix filesystem.  */
/* FIXME !!! */
#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 /* _S390_BITOPS_H */