1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright IBM Corp. 1999,2013 4 * 5 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>, 6 * 7 * The description below was taken in large parts from the powerpc 8 * bitops header file: 9 * Within a word, bits are numbered LSB first. Lot's of places make 10 * this assumption by directly testing bits with (val & (1<<nr)). 11 * This can cause confusion for large (> 1 word) bitmaps on a 12 * big-endian system because, unlike little endian, the number of each 13 * bit depends on the word size. 14 * 15 * The bitop functions are defined to work on unsigned longs, so the bits 16 * end up numbered: 17 * |63..............0|127............64|191...........128|255...........192| 18 * 19 * We also have special functions which work with an MSB0 encoding. 20 * The bits are numbered: 21 * |0..............63|64............127|128...........191|192...........255| 22 * 23 * The main difference is that bit 0-63 in the bit number field needs to be 24 * reversed compared to the LSB0 encoded bit fields. This can be achieved by 25 * XOR with 0x3f. 26 * 27 */ 28 29 #ifndef _S390_BITOPS_H 30 #define _S390_BITOPS_H 31 32 #ifndef _LINUX_BITOPS_H 33 #error only <linux/bitops.h> can be included directly 34 #endif 35 36 #include <linux/typecheck.h> 37 #include <linux/compiler.h> 38 #include <linux/types.h> 39 #include <asm/atomic_ops.h> 40 #include <asm/barrier.h> 41 42 #define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG) 43 44 static inline unsigned long * 45 __bitops_word(unsigned long nr, const volatile unsigned long *ptr) 46 { 47 unsigned long addr; 48 49 addr = (unsigned long)ptr + ((nr ^ (nr & (BITS_PER_LONG - 1))) >> 3); 50 return (unsigned long *)addr; 51 } 52 53 static inline unsigned long __bitops_mask(unsigned long nr) 54 { 55 return 1UL << (nr & (BITS_PER_LONG - 1)); 56 } 57 58 static __always_inline void arch_set_bit(unsigned long nr, volatile unsigned long *ptr) 59 { 60 unsigned long *addr = __bitops_word(nr, ptr); 61 unsigned long mask = __bitops_mask(nr); 62 63 __atomic64_or(mask, (long *)addr); 64 } 65 66 static __always_inline void arch_clear_bit(unsigned long nr, volatile unsigned long *ptr) 67 { 68 unsigned long *addr = __bitops_word(nr, ptr); 69 unsigned long mask = __bitops_mask(nr); 70 71 __atomic64_and(~mask, (long *)addr); 72 } 73 74 static __always_inline void arch_change_bit(unsigned long nr, 75 volatile unsigned long *ptr) 76 { 77 unsigned long *addr = __bitops_word(nr, ptr); 78 unsigned long mask = __bitops_mask(nr); 79 80 __atomic64_xor(mask, (long *)addr); 81 } 82 83 static inline bool arch_test_and_set_bit(unsigned long nr, 84 volatile unsigned long *ptr) 85 { 86 unsigned long *addr = __bitops_word(nr, ptr); 87 unsigned long mask = __bitops_mask(nr); 88 unsigned long old; 89 90 old = __atomic64_or_barrier(mask, (long *)addr); 91 return old & mask; 92 } 93 94 static inline bool arch_test_and_clear_bit(unsigned long nr, 95 volatile unsigned long *ptr) 96 { 97 unsigned long *addr = __bitops_word(nr, ptr); 98 unsigned long mask = __bitops_mask(nr); 99 unsigned long old; 100 101 old = __atomic64_and_barrier(~mask, (long *)addr); 102 return old & mask; 103 } 104 105 static inline bool arch_test_and_change_bit(unsigned long nr, 106 volatile unsigned long *ptr) 107 { 108 unsigned long *addr = __bitops_word(nr, ptr); 109 unsigned long mask = __bitops_mask(nr); 110 unsigned long old; 111 112 old = __atomic64_xor_barrier(mask, (long *)addr); 113 return old & mask; 114 } 115 116 static inline void arch___set_bit(unsigned long nr, volatile unsigned long *ptr) 117 { 118 unsigned long *addr = __bitops_word(nr, ptr); 119 unsigned long mask = __bitops_mask(nr); 120 121 *addr |= mask; 122 } 123 124 static inline void arch___clear_bit(unsigned long nr, 125 volatile unsigned long *ptr) 126 { 127 unsigned long *addr = __bitops_word(nr, ptr); 128 unsigned long mask = __bitops_mask(nr); 129 130 *addr &= ~mask; 131 } 132 133 static inline void arch___change_bit(unsigned long nr, 134 volatile unsigned long *ptr) 135 { 136 unsigned long *addr = __bitops_word(nr, ptr); 137 unsigned long mask = __bitops_mask(nr); 138 139 *addr ^= mask; 140 } 141 142 static inline bool arch___test_and_set_bit(unsigned long nr, 143 volatile unsigned long *ptr) 144 { 145 unsigned long *addr = __bitops_word(nr, ptr); 146 unsigned long mask = __bitops_mask(nr); 147 unsigned long old; 148 149 old = *addr; 150 *addr |= mask; 151 return old & mask; 152 } 153 154 static inline bool arch___test_and_clear_bit(unsigned long nr, 155 volatile unsigned long *ptr) 156 { 157 unsigned long *addr = __bitops_word(nr, ptr); 158 unsigned long mask = __bitops_mask(nr); 159 unsigned long old; 160 161 old = *addr; 162 *addr &= ~mask; 163 return old & mask; 164 } 165 166 static inline bool arch___test_and_change_bit(unsigned long nr, 167 volatile unsigned long *ptr) 168 { 169 unsigned long *addr = __bitops_word(nr, ptr); 170 unsigned long mask = __bitops_mask(nr); 171 unsigned long old; 172 173 old = *addr; 174 *addr ^= mask; 175 return old & mask; 176 } 177 178 static inline bool arch_test_bit(unsigned long nr, 179 const volatile unsigned long *ptr) 180 { 181 const volatile unsigned long *addr = __bitops_word(nr, ptr); 182 unsigned long mask = __bitops_mask(nr); 183 184 return *addr & mask; 185 } 186 187 static inline bool arch_test_and_set_bit_lock(unsigned long nr, 188 volatile unsigned long *ptr) 189 { 190 if (arch_test_bit(nr, ptr)) 191 return true; 192 return arch_test_and_set_bit(nr, ptr); 193 } 194 195 static inline void arch_clear_bit_unlock(unsigned long nr, 196 volatile unsigned long *ptr) 197 { 198 smp_mb__before_atomic(); 199 arch_clear_bit(nr, ptr); 200 } 201 202 static inline void arch___clear_bit_unlock(unsigned long nr, 203 volatile unsigned long *ptr) 204 { 205 smp_mb(); 206 arch___clear_bit(nr, ptr); 207 } 208 209 #include <asm-generic/bitops/instrumented-atomic.h> 210 #include <asm-generic/bitops/instrumented-non-atomic.h> 211 #include <asm-generic/bitops/instrumented-lock.h> 212 213 /* 214 * Functions which use MSB0 bit numbering. 215 * The bits are numbered: 216 * |0..............63|64............127|128...........191|192...........255| 217 */ 218 unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size); 219 unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size, 220 unsigned long offset); 221 222 #define for_each_set_bit_inv(bit, addr, size) \ 223 for ((bit) = find_first_bit_inv((addr), (size)); \ 224 (bit) < (size); \ 225 (bit) = find_next_bit_inv((addr), (size), (bit) + 1)) 226 227 static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 228 { 229 return set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 230 } 231 232 static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 233 { 234 return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 235 } 236 237 static inline bool test_and_clear_bit_inv(unsigned long nr, 238 volatile unsigned long *ptr) 239 { 240 return test_and_clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 241 } 242 243 static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 244 { 245 return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 246 } 247 248 static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 249 { 250 return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 251 } 252 253 static inline bool test_bit_inv(unsigned long nr, 254 const volatile unsigned long *ptr) 255 { 256 return test_bit(nr ^ (BITS_PER_LONG - 1), ptr); 257 } 258 259 /** 260 * __flogr - find leftmost one 261 * @word - The word to search 262 * 263 * Returns the bit number of the most significant bit set, 264 * where the most significant bit has bit number 0. 265 * If no bit is set this function returns 64. 266 */ 267 static inline unsigned char __flogr(unsigned long word) 268 { 269 if (__builtin_constant_p(word)) { 270 unsigned long bit = 0; 271 272 if (!word) 273 return 64; 274 if (!(word & 0xffffffff00000000UL)) { 275 word <<= 32; 276 bit += 32; 277 } 278 if (!(word & 0xffff000000000000UL)) { 279 word <<= 16; 280 bit += 16; 281 } 282 if (!(word & 0xff00000000000000UL)) { 283 word <<= 8; 284 bit += 8; 285 } 286 if (!(word & 0xf000000000000000UL)) { 287 word <<= 4; 288 bit += 4; 289 } 290 if (!(word & 0xc000000000000000UL)) { 291 word <<= 2; 292 bit += 2; 293 } 294 if (!(word & 0x8000000000000000UL)) { 295 word <<= 1; 296 bit += 1; 297 } 298 return bit; 299 } else { 300 union register_pair rp; 301 302 rp.even = word; 303 asm volatile( 304 " flogr %[rp],%[rp]\n" 305 : [rp] "+d" (rp.pair) : : "cc"); 306 return rp.even; 307 } 308 } 309 310 /** 311 * __ffs - find first bit in word. 312 * @word: The word to search 313 * 314 * Undefined if no bit exists, so code should check against 0 first. 315 */ 316 static inline unsigned long __ffs(unsigned long word) 317 { 318 return __flogr(-word & word) ^ (BITS_PER_LONG - 1); 319 } 320 321 /** 322 * ffs - find first bit set 323 * @word: the word to search 324 * 325 * This is defined the same way as the libc and 326 * compiler builtin ffs routines (man ffs). 327 */ 328 static inline int ffs(int word) 329 { 330 unsigned long mask = 2 * BITS_PER_LONG - 1; 331 unsigned int val = (unsigned int)word; 332 333 return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask; 334 } 335 336 /** 337 * __fls - find last (most-significant) set bit in a long word 338 * @word: the word to search 339 * 340 * Undefined if no set bit exists, so code should check against 0 first. 341 */ 342 static inline unsigned long __fls(unsigned long word) 343 { 344 return __flogr(word) ^ (BITS_PER_LONG - 1); 345 } 346 347 /** 348 * fls64 - find last set bit in a 64-bit word 349 * @word: the word to search 350 * 351 * This is defined in a similar way as the libc and compiler builtin 352 * ffsll, but returns the position of the most significant set bit. 353 * 354 * fls64(value) returns 0 if value is 0 or the position of the last 355 * set bit if value is nonzero. The last (most significant) bit is 356 * at position 64. 357 */ 358 static inline int fls64(unsigned long word) 359 { 360 unsigned long mask = 2 * BITS_PER_LONG - 1; 361 362 return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask; 363 } 364 365 /** 366 * fls - find last (most-significant) bit set 367 * @word: the word to search 368 * 369 * This is defined the same way as ffs. 370 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. 371 */ 372 static inline int fls(unsigned int word) 373 { 374 return fls64(word); 375 } 376 377 #include <asm-generic/bitops/ffz.h> 378 #include <asm-generic/bitops/hweight.h> 379 #include <asm-generic/bitops/sched.h> 380 #include <asm-generic/bitops/le.h> 381 #include <asm-generic/bitops/ext2-atomic-setbit.h> 382 383 #endif /* _S390_BITOPS_H */ 384