LXR linux/arch/s390/include/asm/bitops.h

   1/*
   2 *    Copyright IBM Corp. 1999,2013
   3 *
   4 *    Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
   5 *
   6 * The description below was taken in large parts from the powerpc
   7 * bitops header file:
   8 * Within a word, bits are numbered LSB first.  Lot's of places make
   9 * this assumption by directly testing bits with (val & (1<<nr)).
  10 * This can cause confusion for large (> 1 word) bitmaps on a
  11 * big-endian system because, unlike little endian, the number of each
  12 * bit depends on the word size.
  13 *
  14 * The bitop functions are defined to work on unsigned longs, so for an
  15 * s390x system the bits end up numbered:
  16 *   |63..............0|127............64|191...........128|255...........192|
  17 * and on s390:
  18 *   |31.....0|63....32|95....64|127...96|159..128|191..160|223..192|255..224|
  19 *
  20 * There are a few little-endian macros used mostly for filesystem
  21 * bitmaps, these work on similar bit arrays layouts, but
  22 * byte-oriented:
  23 *   |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56|
  24 *
  25 * The main difference is that bit 3-5 (64b) or 3-4 (32b) in the bit
  26 * number field needs to be reversed compared to the big-endian bit
  27 * fields. This can be achieved by XOR with 0x38 (64b) or 0x18 (32b).
  28 *
  29 * We also have special functions which work with an MSB0 encoding:
  30 * on an s390x system the bits are numbered:
  31 *   |0..............63|64............127|128...........191|192...........255|
  32 * and on s390:
  33 *   |0.....31|32....63|64....95|96...127|128..159|160..191|192..223|224..255|
  34 *
  35 * The main difference is that bit 0-63 (64b) or 0-31 (32b) in the bit
  36 * number field needs to be reversed compared to the LSB0 encoded bit
  37 * fields. This can be achieved by XOR with 0x3f (64b) or 0x1f (32b).
  38 *
  39 */
  40
  41#ifndef _S390_BITOPS_H
  42#define _S390_BITOPS_H
  43
  44#ifndef _LINUX_BITOPS_H
  45#error only <linux/bitops.h> can be included directly
  46#endif
  47
  48#include <linux/typecheck.h>
  49#include <linux/compiler.h>
  50#include <asm/barrier.h>
  51
  52#define __BITOPS_NO_BARRIER     "\n"
  53
  54#ifndef CONFIG_64BIT
  55
  56#define __BITOPS_OR             "or"
  57#define __BITOPS_AND            "nr"
  58#define __BITOPS_XOR            "xr"
  59#define __BITOPS_BARRIER        "\n"
  60
  61#define __BITOPS_LOOP(__addr, __val, __op_string, __barrier)    \
  62({                                                              \
  63        unsigned long __old, __new;                             \
  64                                                                \
  65        typecheck(unsigned long *, (__addr));                   \
  66        asm volatile(                                           \
  67                "       l       %0,%2\n"                        \
  68                "0:     lr      %1,%0\n"                        \
  69                __op_string "   %1,%3\n"                        \
  70                "       cs      %0,%1,%2\n"                     \
  71                "       jl      0b"                             \
  72                : "=&d" (__old), "=&d" (__new), "+Q" (*(__addr))\
  73                : "d" (__val)                                   \
  74                : "cc", "memory");                              \
  75        __old;                                                  \
  76})
  77
  78#else /* CONFIG_64BIT */
  79
  80#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
  81
  82#define __BITOPS_OR             "laog"
  83#define __BITOPS_AND            "lang"
  84#define __BITOPS_XOR            "laxg"
  85#define __BITOPS_BARRIER        "bcr    14,0\n"
  86
  87#define __BITOPS_LOOP(__addr, __val, __op_string, __barrier)    \
  88({                                                              \
  89        unsigned long __old;                                    \
  90                                                                \
  91        typecheck(unsigned long *, (__addr));                   \
  92        asm volatile(                                           \
  93                __barrier                                       \
  94                __op_string "   %0,%2,%1\n"                     \
  95                __barrier                                       \
  96                : "=d" (__old), "+Q" (*(__addr))                \
  97                : "d" (__val)                                   \
  98                : "cc", "memory");                              \
  99        __old;                                                  \
 100})
 101
 102#else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
 103
 104#define __BITOPS_OR             "ogr"
 105#define __BITOPS_AND            "ngr"
 106#define __BITOPS_XOR            "xgr"
 107#define __BITOPS_BARRIER        "\n"
 108
 109#define __BITOPS_LOOP(__addr, __val, __op_string, __barrier)    \
 110({                                                              \
 111        unsigned long __old, __new;                             \
 112                                                                \
 113        typecheck(unsigned long *, (__addr));                   \
 114        asm volatile(                                           \
 115                "       lg      %0,%2\n"                        \
 116                "0:     lgr     %1,%0\n"                        \
 117                __op_string "   %1,%3\n"                        \
 118                "       csg     %0,%1,%2\n"                     \
 119                "       jl      0b"                             \
 120                : "=&d" (__old), "=&d" (__new), "+Q" (*(__addr))\
 121                : "d" (__val)                                   \
 122                : "cc", "memory");                              \
 123        __old;                                                  \
 124})
 125
 126#endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
 127
 128#endif /* CONFIG_64BIT */
 129
 130#define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG)
 131
 132static inline unsigned long *
 133__bitops_word(unsigned long nr, volatile unsigned long *ptr)
 134{
 135        unsigned long addr;
 136
 137        addr = (unsigned long)ptr + ((nr ^ (nr & (BITS_PER_LONG - 1))) >> 3);
 138        return (unsigned long *)addr;
 139}
 140
 141static inline unsigned char *
 142__bitops_byte(unsigned long nr, volatile unsigned long *ptr)
 143{
 144        return ((unsigned char *)ptr) + ((nr ^ (BITS_PER_LONG - 8)) >> 3);
 145}
 146
 147static inline void set_bit(unsigned long nr, volatile unsigned long *ptr)
 148{
 149        unsigned long *addr = __bitops_word(nr, ptr);
 150        unsigned long mask;
 151
 152#ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
 153        if (__builtin_constant_p(nr)) {
 154                unsigned char *caddr = __bitops_byte(nr, ptr);
 155
 156                asm volatile(
 157                        "oi     %0,%b1\n"
 158                        : "+Q" (*caddr)
 159                        : "i" (1 << (nr & 7))
 160                        : "cc", "memory");
 161                return;
 162        }
 163#endif
 164        mask = 1UL << (nr & (BITS_PER_LONG - 1));
 165        __BITOPS_LOOP(addr, mask, __BITOPS_OR, __BITOPS_NO_BARRIER);
 166}
 167
 168static inline void clear_bit(unsigned long nr, volatile unsigned long *ptr)
 169{
 170        unsigned long *addr = __bitops_word(nr, ptr);
 171        unsigned long mask;
 172
 173#ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
 174        if (__builtin_constant_p(nr)) {
 175                unsigned char *caddr = __bitops_byte(nr, ptr);
 176
 177                asm volatile(
 178                        "ni     %0,%b1\n"
 179                        : "+Q" (*caddr)
 180                        : "i" (~(1 << (nr & 7)))
 181                        : "cc", "memory");
 182                return;
 183        }
 184#endif
 185        mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
 186        __BITOPS_LOOP(addr, mask, __BITOPS_AND, __BITOPS_NO_BARRIER);
 187}
 188
 189static inline void change_bit(unsigned long nr, volatile unsigned long *ptr)
 190{
 191        unsigned long *addr = __bitops_word(nr, ptr);
 192        unsigned long mask;
 193
 194#ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
 195        if (__builtin_constant_p(nr)) {
 196                unsigned char *caddr = __bitops_byte(nr, ptr);
 197
 198                asm volatile(
 199                        "xi     %0,%b1\n"
 200                        : "+Q" (*caddr)
 201                        : "i" (1 << (nr & 7))
 202                        : "cc", "memory");
 203                return;
 204        }
 205#endif
 206        mask = 1UL << (nr & (BITS_PER_LONG - 1));
 207        __BITOPS_LOOP(addr, mask, __BITOPS_XOR, __BITOPS_NO_BARRIER);
 208}
 209
 210static inline int
 211test_and_set_bit(unsigned long nr, volatile unsigned long *ptr)
 212{
 213        unsigned long *addr = __bitops_word(nr, ptr);
 214        unsigned long old, mask;
 215
 216        mask = 1UL << (nr & (BITS_PER_LONG - 1));
 217        old = __BITOPS_LOOP(addr, mask, __BITOPS_OR, __BITOPS_BARRIER);
 218        return (old & mask) != 0;
 219}
 220
 221static inline int
 222test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr)
 223{
 224        unsigned long *addr = __bitops_word(nr, ptr);
 225        unsigned long old, mask;
 226
 227        mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
 228        old = __BITOPS_LOOP(addr, mask, __BITOPS_AND, __BITOPS_BARRIER);
 229        return (old & ~mask) != 0;
 230}
 231
 232static inline int
 233test_and_change_bit(unsigned long nr, volatile unsigned long *ptr)
 234{
 235        unsigned long *addr = __bitops_word(nr, ptr);
 236        unsigned long old, mask;
 237
 238        mask = 1UL << (nr & (BITS_PER_LONG - 1));
 239        old = __BITOPS_LOOP(addr, mask, __BITOPS_XOR, __BITOPS_BARRIER);
 240        return (old & mask) != 0;
 241}
 242
 243static inline void __set_bit(unsigned long nr, volatile unsigned long *ptr)
 244{
 245        unsigned char *addr = __bitops_byte(nr, ptr);
 246
 247        *addr |= 1 << (nr & 7);
 248}
 249
 250static inline void 
 251__clear_bit(unsigned long nr, volatile unsigned long *ptr)
 252{
 253        unsigned char *addr = __bitops_byte(nr, ptr);
 254
 255        *addr &= ~(1 << (nr & 7));
 256}
 257
 258static inline void __change_bit(unsigned long nr, volatile unsigned long *ptr)
 259{
 260        unsigned char *addr = __bitops_byte(nr, ptr);
 261
 262        *addr ^= 1 << (nr & 7);
 263}
 264
 265static inline int
 266__test_and_set_bit(unsigned long nr, volatile unsigned long *ptr)
 267{
 268        unsigned char *addr = __bitops_byte(nr, ptr);
 269        unsigned char ch;
 270
 271        ch = *addr;
 272        *addr |= 1 << (nr & 7);
 273        return (ch >> (nr & 7)) & 1;
 274}
 275
 276static inline int
 277__test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr)
 278{
 279        unsigned char *addr = __bitops_byte(nr, ptr);
 280        unsigned char ch;
 281
 282        ch = *addr;
 283        *addr &= ~(1 << (nr & 7));
 284        return (ch >> (nr & 7)) & 1;
 285}
 286
 287static inline int
 288__test_and_change_bit(unsigned long nr, volatile unsigned long *ptr)
 289{
 290        unsigned char *addr = __bitops_byte(nr, ptr);
 291        unsigned char ch;
 292
 293        ch = *addr;
 294        *addr ^= 1 << (nr & 7);
 295        return (ch >> (nr & 7)) & 1;
 296}
 297
 298static inline int test_bit(unsigned long nr, const volatile unsigned long *ptr)
 299{
 300        const volatile unsigned char *addr;
 301
 302        addr = ((const volatile unsigned char *)ptr);
 303        addr += (nr ^ (BITS_PER_LONG - 8)) >> 3;
 304        return (*addr >> (nr & 7)) & 1;
 305}
 306
 307/*
 308 * Functions which use MSB0 bit numbering.
 309 * On an s390x system the bits are numbered:
 310 *   |0..............63|64............127|128...........191|192...........255|
 311 * and on s390:
 312 *   |0.....31|32....63|64....95|96...127|128..159|160..191|192..223|224..255|
 313 */
 314unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size);
 315unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size,
 316                                unsigned long offset);
 317
 318static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
 319{
 320        return set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
 321}
 322
 323static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
 324{
 325        return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
 326}
 327
 328static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
 329{
 330        return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
 331}
 332
 333static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
 334{
 335        return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
 336}
 337
 338static inline int test_bit_inv(unsigned long nr,
 339                               const volatile unsigned long *ptr)
 340{
 341        return test_bit(nr ^ (BITS_PER_LONG - 1), ptr);
 342}
 343
 344#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
 345
 346/**
 347 * __flogr - find leftmost one
 348 * @word - The word to search
 349 *
 350 * Returns the bit number of the most significant bit set,
 351 * where the most significant bit has bit number 0.
 352 * If no bit is set this function returns 64.
 353 */
 354static inline unsigned char __flogr(unsigned long word)
 355{
 356        if (__builtin_constant_p(word)) {
 357                unsigned long bit = 0;
 358
 359                if (!word)
 360                        return 64;
 361                if (!(word & 0xffffffff00000000UL)) {
 362                        word <<= 32;
 363                        bit += 32;
 364                }
 365                if (!(word & 0xffff000000000000UL)) {
 366                        word <<= 16;
 367                        bit += 16;
 368                }
 369                if (!(word & 0xff00000000000000UL)) {
 370                        word <<= 8;
 371                        bit += 8;
 372                }
 373                if (!(word & 0xf000000000000000UL)) {
 374                        word <<= 4;
 375                        bit += 4;
 376                }
 377                if (!(word & 0xc000000000000000UL)) {
 378                        word <<= 2;
 379                        bit += 2;
 380                }
 381                if (!(word & 0x8000000000000000UL)) {
 382                        word <<= 1;
 383                        bit += 1;
 384                }
 385                return bit;
 386        } else {
 387                register unsigned long bit asm("4") = word;
 388                register unsigned long out asm("5");
 389
 390                asm volatile(
 391                        "       flogr   %[bit],%[bit]\n"
 392                        : [bit] "+d" (bit), [out] "=d" (out) : : "cc");
 393                return bit;
 394        }
 395}
 396
 397/**
 398 * __ffs - find first bit in word.
 399 * @word: The word to search
 400 *
 401 * Undefined if no bit exists, so code should check against 0 first.
 402 */
 403static inline unsigned long __ffs(unsigned long word)
 404{
 405        return __flogr(-word & word) ^ (BITS_PER_LONG - 1);
 406}
 407
 408/**
 409 * ffs - find first bit set
 410 * @word: the word to search
 411 *
 412 * This is defined the same way as the libc and
 413 * compiler builtin ffs routines (man ffs).
 414 */
 415static inline int ffs(int word)
 416{
 417        unsigned long mask = 2 * BITS_PER_LONG - 1;
 418        unsigned int val = (unsigned int)word;
 419
 420        return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask;
 421}
 422
 423/**
 424 * __fls - find last (most-significant) set bit in a long word
 425 * @word: the word to search
 426 *
 427 * Undefined if no set bit exists, so code should check against 0 first.
 428 */
 429static inline unsigned long __fls(unsigned long word)
 430{
 431        return __flogr(word) ^ (BITS_PER_LONG - 1);
 432}
 433
 434/**
 435 * fls64 - find last set bit in a 64-bit word
 436 * @word: the word to search
 437 *
 438 * This is defined in a similar way as the libc and compiler builtin
 439 * ffsll, but returns the position of the most significant set bit.
 440 *
 441 * fls64(value) returns 0 if value is 0 or the position of the last
 442 * set bit if value is nonzero. The last (most significant) bit is
 443 * at position 64.
 444 */
 445static inline int fls64(unsigned long word)
 446{
 447        unsigned long mask = 2 * BITS_PER_LONG - 1;
 448
 449        return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask;
 450}
 451
 452/**
 453 * fls - find last (most-significant) bit set
 454 * @word: the word to search
 455 *
 456 * This is defined the same way as ffs.
 457 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
 458 */
 459static inline int fls(int word)
 460{
 461        return fls64((unsigned int)word);
 462}
 463
 464#else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
 465
 466#include <asm-generic/bitops/__ffs.h>
 467#include <asm-generic/bitops/ffs.h>
 468#include <asm-generic/bitops/__fls.h>
 469#include <asm-generic/bitops/fls.h>
 470#include <asm-generic/bitops/fls64.h>
 471
 472#endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
 473
 474#include <asm-generic/bitops/ffz.h>
 475#include <asm-generic/bitops/find.h>
 476#include <asm-generic/bitops/hweight.h>
 477#include <asm-generic/bitops/lock.h>
 478#include <asm-generic/bitops/sched.h>
 479#include <asm-generic/bitops/le.h>
 480#include <asm-generic/bitops/ext2-atomic-setbit.h>
 481
 482#endif /* _S390_BITOPS_H */
 483