arch/ia64/include/asm/bitops.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_IA64_BITOPS_H
   3 #define _ASM_IA64_BITOPS_H
   4
   5 /*
   6  * Copyright (C) 1998-2003 Hewlett-Packard Co
   7  *      David Mosberger-Tang <davidm@hpl.hp.com>
   8  *
   9  * 02/06/02 find_next_bit() and find_first_bit() added from Erich Focht's ia64
  10  * O(1) scheduler patch
  11  */
  12
  13 #ifndef _LINUX_BITOPS_H
  14 #error only <linux/bitops.h> can be included directly
  15 #endif
  16
  17 #include <linux/compiler.h>
  18 #include <linux/types.h>
  19 #include <asm/intrinsics.h>
  20 #include <asm/barrier.h>
  21
  22 /**
  23  * set_bit - Atomically set a bit in memory
  24  * @nr: the bit to set
  25  * @addr: the address to start counting from
  26  *
  27  * This function is atomic and may not be reordered.  See __set_bit()
  28  * if you do not require the atomic guarantees.
  29  * Note that @nr may be almost arbitrarily large; this function is not
  30  * restricted to acting on a single-word quantity.
  31  *
  32  * The address must be (at least) "long" aligned.
  33  * Note that there are driver (e.g., eepro100) which use these operations to
  34  * operate on hw-defined data-structures, so we can't easily change these
  35  * operations to force a bigger alignment.
  36  *
  37  * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
  38  */
  39 static __inline__ void
  40 set_bit (int nr, volatile void *addr)
  41 {
  42         __u32 bit, old, new;
  43         volatile __u32 *m;
  44         CMPXCHG_BUGCHECK_DECL
  45
  46         m = (volatile __u32 *) addr + (nr >> 5);
  47         bit = 1 << (nr & 31);
  48         do {
  49                 CMPXCHG_BUGCHECK(m);
  50                 old = *m;
  51                 new = old | bit;
  52         } while (cmpxchg_acq(m, old, new) != old);
  53 }
  54
  55 /**
  56  * __set_bit - Set a bit in memory
  57  * @nr: the bit to set
  58  * @addr: the address to start counting from
  59  *
  60  * Unlike set_bit(), this function is non-atomic and may be reordered.
  61  * If it's called on the same region of memory simultaneously, the effect
  62  * may be that only one operation succeeds.
  63  */
  64 static __inline__ void
  65 __set_bit (int nr, volatile void *addr)
  66 {
  67         *((__u32 *) addr + (nr >> 5)) |= (1 << (nr & 31));
  68 }
  69
  70 /**
  71  * clear_bit - Clears a bit in memory
  72  * @nr: Bit to clear
  73  * @addr: Address to start counting from
  74  *
  75  * clear_bit() is atomic and may not be reordered.  However, it does
  76  * not contain a memory barrier, so if it is used for locking purposes,
  77  * you should call smp_mb__before_atomic() and/or smp_mb__after_atomic()
  78  * in order to ensure changes are visible on other processors.
  79  */
  80 static __inline__ void
  81 clear_bit (int nr, volatile void *addr)
  82 {
  83         __u32 mask, old, new;
  84         volatile __u32 *m;
  85         CMPXCHG_BUGCHECK_DECL
  86
  87         m = (volatile __u32 *) addr + (nr >> 5);
  88         mask = ~(1 << (nr & 31));
  89         do {
  90                 CMPXCHG_BUGCHECK(m);
  91                 old = *m;
  92                 new = old & mask;
  93         } while (cmpxchg_acq(m, old, new) != old);
  94 }
  95
  96 /**
  97  * clear_bit_unlock - Clears a bit in memory with release
  98  * @nr: Bit to clear
  99  * @addr: Address to start counting from
 100  *
 101  * clear_bit_unlock() is atomic and may not be reordered.  It does
 102  * contain a memory barrier suitable for unlock type operations.
 103  */
 104 static __inline__ void
 105 clear_bit_unlock (int nr, volatile void *addr)
 106 {
 107         __u32 mask, old, new;
 108         volatile __u32 *m;
 109         CMPXCHG_BUGCHECK_DECL
 110
 111         m = (volatile __u32 *) addr + (nr >> 5);
 112         mask = ~(1 << (nr & 31));
 113         do {
 114                 CMPXCHG_BUGCHECK(m);
 115                 old = *m;
 116                 new = old & mask;
 117         } while (cmpxchg_rel(m, old, new) != old);
 118 }
 119
 120 /**
 121  * __clear_bit_unlock - Non-atomically clears a bit in memory with release
 122  * @nr: Bit to clear
 123  * @addr: Address to start counting from
 124  *
 125  * Similarly to clear_bit_unlock, the implementation uses a store
 126  * with release semantics. See also arch_spin_unlock().
 127  */
 128 static __inline__ void
 129 __clear_bit_unlock(int nr, void *addr)
 130 {
 131         __u32 * const m = (__u32 *) addr + (nr >> 5);
 132         __u32 const new = *m & ~(1 << (nr & 31));
 133
 134         ia64_st4_rel_nta(m, new);
 135 }
 136
 137 /**
 138  * __clear_bit - Clears a bit in memory (non-atomic version)
 139  * @nr: the bit to clear
 140  * @addr: the address to start counting from
 141  *
 142  * Unlike clear_bit(), this function is non-atomic and may be reordered.
 143  * If it's called on the same region of memory simultaneously, the effect
 144  * may be that only one operation succeeds.
 145  */
 146 static __inline__ void
 147 __clear_bit (int nr, volatile void *addr)
 148 {
 149         *((__u32 *) addr + (nr >> 5)) &= ~(1 << (nr & 31));
 150 }
 151
 152 /**
 153  * change_bit - Toggle a bit in memory
 154  * @nr: Bit to toggle
 155  * @addr: Address to start counting from
 156  *
 157  * change_bit() is atomic and may not be reordered.
 158  * Note that @nr may be almost arbitrarily large; this function is not
 159  * restricted to acting on a single-word quantity.
 160  */
 161 static __inline__ void
 162 change_bit (int nr, volatile void *addr)
 163 {
 164         __u32 bit, old, new;
 165         volatile __u32 *m;
 166         CMPXCHG_BUGCHECK_DECL
 167
 168         m = (volatile __u32 *) addr + (nr >> 5);
 169         bit = (1 << (nr & 31));
 170         do {
 171                 CMPXCHG_BUGCHECK(m);
 172                 old = *m;
 173                 new = old ^ bit;
 174         } while (cmpxchg_acq(m, old, new) != old);
 175 }
 176
 177 /**
 178  * __change_bit - Toggle a bit in memory
 179  * @nr: the bit to toggle
 180  * @addr: the address to start counting from
 181  *
 182  * Unlike change_bit(), this function is non-atomic and may be reordered.
 183  * If it's called on the same region of memory simultaneously, the effect
 184  * may be that only one operation succeeds.
 185  */
 186 static __inline__ void
 187 __change_bit (int nr, volatile void *addr)
 188 {
 189         *((__u32 *) addr + (nr >> 5)) ^= (1 << (nr & 31));
 190 }
 191
 192 /**
 193  * test_and_set_bit - Set a bit and return its old value
 194  * @nr: Bit to set
 195  * @addr: Address to count from
 196  *
 197  * This operation is atomic and cannot be reordered.
 198  * It also implies the acquisition side of the memory barrier.
 199  */
 200 static __inline__ int
 201 test_and_set_bit (int nr, volatile void *addr)
 202 {
 203         __u32 bit, old, new;
 204         volatile __u32 *m;
 205         CMPXCHG_BUGCHECK_DECL
 206
 207         m = (volatile __u32 *) addr + (nr >> 5);
 208         bit = 1 << (nr & 31);
 209         do {
 210                 CMPXCHG_BUGCHECK(m);
 211                 old = *m;
 212                 new = old | bit;
 213         } while (cmpxchg_acq(m, old, new) != old);
 214         return (old & bit) != 0;
 215 }
 216
 217 /**
 218  * test_and_set_bit_lock - Set a bit and return its old value for lock
 219  * @nr: Bit to set
 220  * @addr: Address to count from
 221  *
 222  * This is the same as test_and_set_bit on ia64
 223  */
 224 #define test_and_set_bit_lock test_and_set_bit
 225
 226 /**
 227  * __test_and_set_bit - Set a bit and return its old value
 228  * @nr: Bit to set
 229  * @addr: Address to count from
 230  *
 231  * This operation is non-atomic and can be reordered.
 232  * If two examples of this operation race, one can appear to succeed
 233  * but actually fail.  You must protect multiple accesses with a lock.
 234  */
 235 static __inline__ int
 236 __test_and_set_bit (int nr, volatile void *addr)
 237 {
 238         __u32 *p = (__u32 *) addr + (nr >> 5);
 239         __u32 m = 1 << (nr & 31);
 240         int oldbitset = (*p & m) != 0;
 241
 242         *p |= m;
 243         return oldbitset;
 244 }
 245
 246 /**
 247  * test_and_clear_bit - Clear a bit and return its old value
 248  * @nr: Bit to clear
 249  * @addr: Address to count from
 250  *
 251  * This operation is atomic and cannot be reordered.
 252  * It also implies the acquisition side of the memory barrier.
 253  */
 254 static __inline__ int
 255 test_and_clear_bit (int nr, volatile void *addr)
 256 {
 257         __u32 mask, old, new;
 258         volatile __u32 *m;
 259         CMPXCHG_BUGCHECK_DECL
 260
 261         m = (volatile __u32 *) addr + (nr >> 5);
 262         mask = ~(1 << (nr & 31));
 263         do {
 264                 CMPXCHG_BUGCHECK(m);
 265                 old = *m;
 266                 new = old & mask;
 267         } while (cmpxchg_acq(m, old, new) != old);
 268         return (old & ~mask) != 0;
 269 }
 270
 271 /**
 272  * __test_and_clear_bit - Clear a bit and return its old value
 273  * @nr: Bit to clear
 274  * @addr: Address to count from
 275  *
 276  * This operation is non-atomic and can be reordered.
 277  * If two examples of this operation race, one can appear to succeed
 278  * but actually fail.  You must protect multiple accesses with a lock.
 279  */
 280 static __inline__ int
 281 __test_and_clear_bit(int nr, volatile void * addr)
 282 {
 283         __u32 *p = (__u32 *) addr + (nr >> 5);
 284         __u32 m = 1 << (nr & 31);
 285         int oldbitset = (*p & m) != 0;
 286
 287         *p &= ~m;
 288         return oldbitset;
 289 }
 290
 291 /**
 292  * test_and_change_bit - Change a bit and return its old value
 293  * @nr: Bit to change
 294  * @addr: Address to count from
 295  *
 296  * This operation is atomic and cannot be reordered.
 297  * It also implies the acquisition side of the memory barrier.
 298  */
 299 static __inline__ int
 300 test_and_change_bit (int nr, volatile void *addr)
 301 {
 302         __u32 bit, old, new;
 303         volatile __u32 *m;
 304         CMPXCHG_BUGCHECK_DECL
 305
 306         m = (volatile __u32 *) addr + (nr >> 5);
 307         bit = (1 << (nr & 31));
 308         do {
 309                 CMPXCHG_BUGCHECK(m);
 310                 old = *m;
 311                 new = old ^ bit;
 312         } while (cmpxchg_acq(m, old, new) != old);
 313         return (old & bit) != 0;
 314 }
 315
 316 /**
 317  * __test_and_change_bit - Change a bit and return its old value
 318  * @nr: Bit to change
 319  * @addr: Address to count from
 320  *
 321  * This operation is non-atomic and can be reordered.
 322  */
 323 static __inline__ int
 324 __test_and_change_bit (int nr, void *addr)
 325 {
 326         __u32 old, bit = (1 << (nr & 31));
 327         __u32 *m = (__u32 *) addr + (nr >> 5);
 328
 329         old = *m;
 330         *m = old ^ bit;
 331         return (old & bit) != 0;
 332 }
 333
 334 static __inline__ int
 335 test_bit (int nr, const volatile void *addr)
 336 {
 337         return 1 & (((const volatile __u32 *) addr)[nr >> 5] >> (nr & 31));
 338 }
 339
 340 /**
 341  * ffz - find the first zero bit in a long word
 342  * @x: The long word to find the bit in
 343  *
 344  * Returns the bit-number (0..63) of the first (least significant) zero bit.
 345  * Undefined if no zero exists, so code should check against ~0UL first...
 346  */
 347 static inline unsigned long
 348 ffz (unsigned long x)
 349 {
 350         unsigned long result;
 351
 352         result = ia64_popcnt(x & (~x - 1));
 353         return result;
 354 }
 355
 356 /**
 357  * __ffs - find first bit in word.
 358  * @x: The word to search
 359  *
 360  * Undefined if no bit exists, so code should check against 0 first.
 361  */
 362 static __inline__ unsigned long
 363 __ffs (unsigned long x)
 364 {
 365         unsigned long result;
 366
 367         result = ia64_popcnt((x-1) & ~x);
 368         return result;
 369 }
 370
 371 #ifdef __KERNEL__
 372
 373 /*
 374  * Return bit number of last (most-significant) bit set.  Undefined
 375  * for x==0.  Bits are numbered from 0..63 (e.g., ia64_fls(9) == 3).
 376  */
 377 static inline unsigned long
 378 ia64_fls (unsigned long x)
 379 {
 380         long double d = x;
 381         long exp;
 382
 383         exp = ia64_getf_exp(d);
 384         return exp - 0xffff;
 385 }
 386
 387 /*
 388  * Find the last (most significant) bit set.  Returns 0 for x==0 and
 389  * bits are numbered from 1..32 (e.g., fls(9) == 4).
 390  */
 391 static inline int
 392 fls (int t)
 393 {
 394         unsigned long x = t & 0xffffffffu;
 395
 396         if (!x)
 397                 return 0;
 398         x |= x >> 1;
 399         x |= x >> 2;
 400         x |= x >> 4;
 401         x |= x >> 8;
 402         x |= x >> 16;
 403         return ia64_popcnt(x);
 404 }
 405
 406 /*
 407  * Find the last (most significant) bit set.  Undefined for x==0.
 408  * Bits are numbered from 0..63 (e.g., __fls(9) == 3).
 409  */
 410 static inline unsigned long
 411 __fls (unsigned long x)
 412 {
 413         x |= x >> 1;
 414         x |= x >> 2;
 415         x |= x >> 4;
 416         x |= x >> 8;
 417         x |= x >> 16;
 418         x |= x >> 32;
 419         return ia64_popcnt(x) - 1;
 420 }
 421
 422 #include <asm-generic/bitops/fls64.h>
 423
 424 #include <asm-generic/bitops/builtin-ffs.h>
 425
 426 /*
 427  * hweightN: returns the hamming weight (i.e. the number
 428  * of bits set) of a N-bit word
 429  */
 430 static __inline__ unsigned long __arch_hweight64(unsigned long x)
 431 {
 432         unsigned long result;
 433         result = ia64_popcnt(x);
 434         return result;
 435 }
 436
 437 #define __arch_hweight32(x) ((unsigned int) __arch_hweight64((x) & 0xfffffffful))
 438 #define __arch_hweight16(x) ((unsigned int) __arch_hweight64((x) & 0xfffful))
 439 #define __arch_hweight8(x)  ((unsigned int) __arch_hweight64((x) & 0xfful))
 440
 441 #include <asm-generic/bitops/const_hweight.h>
 442
 443 #endif /* __KERNEL__ */
 444
 445 #include <asm-generic/bitops/find.h>
 446
 447 #ifdef __KERNEL__
 448
 449 #include <asm-generic/bitops/le.h>
 450
 451 #include <asm-generic/bitops/ext2-atomic-setbit.h>
 452
 453 #include <asm-generic/bitops/sched.h>
 454
 455 #endif /* __KERNEL__ */
 456
 457 #endif /* _ASM_IA64_BITOPS_H */