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 __always_inline void 117 arch___set_bit(unsigned long nr, volatile unsigned long *addr) 118 { 119 unsigned long *p = __bitops_word(nr, addr); 120 unsigned long mask = __bitops_mask(nr); 121 122 *p |= mask; 123 } 124 125 static __always_inline void 126 arch___clear_bit(unsigned long nr, volatile unsigned long *addr) 127 { 128 unsigned long *p = __bitops_word(nr, addr); 129 unsigned long mask = __bitops_mask(nr); 130 131 *p &= ~mask; 132 } 133 134 static __always_inline void 135 arch___change_bit(unsigned long nr, volatile unsigned long *addr) 136 { 137 unsigned long *p = __bitops_word(nr, addr); 138 unsigned long mask = __bitops_mask(nr); 139 140 *p ^= mask; 141 } 142 143 static __always_inline bool 144 arch___test_and_set_bit(unsigned long nr, volatile unsigned long *addr) 145 { 146 unsigned long *p = __bitops_word(nr, addr); 147 unsigned long mask = __bitops_mask(nr); 148 unsigned long old; 149 150 old = *p; 151 *p |= mask; 152 return old & mask; 153 } 154 155 static __always_inline bool 156 arch___test_and_clear_bit(unsigned long nr, volatile unsigned long *addr) 157 { 158 unsigned long *p = __bitops_word(nr, addr); 159 unsigned long mask = __bitops_mask(nr); 160 unsigned long old; 161 162 old = *p; 163 *p &= ~mask; 164 return old & mask; 165 } 166 167 static __always_inline bool 168 arch___test_and_change_bit(unsigned long nr, volatile unsigned long *addr) 169 { 170 unsigned long *p = __bitops_word(nr, addr); 171 unsigned long mask = __bitops_mask(nr); 172 unsigned long old; 173 174 old = *p; 175 *p ^= mask; 176 return old & mask; 177 } 178 179 #define arch_test_bit generic_test_bit 180 #define arch_test_bit_acquire generic_test_bit_acquire 181 182 static inline bool arch_test_and_set_bit_lock(unsigned long nr, 183 volatile unsigned long *ptr) 184 { 185 if (arch_test_bit(nr, ptr)) 186 return true; 187 return arch_test_and_set_bit(nr, ptr); 188 } 189 190 static inline void arch_clear_bit_unlock(unsigned long nr, 191 volatile unsigned long *ptr) 192 { 193 smp_mb__before_atomic(); 194 arch_clear_bit(nr, ptr); 195 } 196 197 static inline void arch___clear_bit_unlock(unsigned long nr, 198 volatile unsigned long *ptr) 199 { 200 smp_mb(); 201 arch___clear_bit(nr, ptr); 202 } 203 204 static inline bool arch_xor_unlock_is_negative_byte(unsigned long mask, 205 volatile unsigned long *ptr) 206 { 207 unsigned long old; 208 209 old = __atomic64_xor_barrier(mask, (long *)ptr); 210 return old & BIT(7); 211 } 212 #define arch_xor_unlock_is_negative_byte arch_xor_unlock_is_negative_byte 213 214 #include <asm-generic/bitops/instrumented-atomic.h> 215 #include <asm-generic/bitops/instrumented-non-atomic.h> 216 #include <asm-generic/bitops/instrumented-lock.h> 217 218 /* 219 * Functions which use MSB0 bit numbering. 220 * The bits are numbered: 221 * |0..............63|64............127|128...........191|192...........255| 222 */ 223 unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size); 224 unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size, 225 unsigned long offset); 226 227 #define for_each_set_bit_inv(bit, addr, size) \ 228 for ((bit) = find_first_bit_inv((addr), (size)); \ 229 (bit) < (size); \ 230 (bit) = find_next_bit_inv((addr), (size), (bit) + 1)) 231 232 static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 233 { 234 return set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 235 } 236 237 static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 238 { 239 return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 240 } 241 242 static inline bool test_and_clear_bit_inv(unsigned long nr, 243 volatile unsigned long *ptr) 244 { 245 return test_and_clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 246 } 247 248 static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 249 { 250 return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 251 } 252 253 static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 254 { 255 return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 256 } 257 258 static inline bool test_bit_inv(unsigned long nr, 259 const volatile unsigned long *ptr) 260 { 261 return test_bit(nr ^ (BITS_PER_LONG - 1), ptr); 262 } 263 264 /** 265 * __flogr - find leftmost one 266 * @word - The word to search 267 * 268 * Returns the bit number of the most significant bit set, 269 * where the most significant bit has bit number 0. 270 * If no bit is set this function returns 64. 271 */ 272 static inline unsigned char __flogr(unsigned long word) 273 { 274 if (__builtin_constant_p(word)) { 275 unsigned long bit = 0; 276 277 if (!word) 278 return 64; 279 if (!(word & 0xffffffff00000000UL)) { 280 word <<= 32; 281 bit += 32; 282 } 283 if (!(word & 0xffff000000000000UL)) { 284 word <<= 16; 285 bit += 16; 286 } 287 if (!(word & 0xff00000000000000UL)) { 288 word <<= 8; 289 bit += 8; 290 } 291 if (!(word & 0xf000000000000000UL)) { 292 word <<= 4; 293 bit += 4; 294 } 295 if (!(word & 0xc000000000000000UL)) { 296 word <<= 2; 297 bit += 2; 298 } 299 if (!(word & 0x8000000000000000UL)) { 300 word <<= 1; 301 bit += 1; 302 } 303 return bit; 304 } else { 305 union register_pair rp; 306 307 rp.even = word; 308 asm volatile( 309 " flogr %[rp],%[rp]\n" 310 : [rp] "+d" (rp.pair) : : "cc"); 311 return rp.even; 312 } 313 } 314 315 /** 316 * __ffs - find first bit in word. 317 * @word: The word to search 318 * 319 * Undefined if no bit exists, so code should check against 0 first. 320 */ 321 static inline unsigned long __ffs(unsigned long word) 322 { 323 return __flogr(-word & word) ^ (BITS_PER_LONG - 1); 324 } 325 326 /** 327 * ffs - find first bit set 328 * @word: the word to search 329 * 330 * This is defined the same way as the libc and 331 * compiler builtin ffs routines (man ffs). 332 */ 333 static inline int ffs(int word) 334 { 335 unsigned long mask = 2 * BITS_PER_LONG - 1; 336 unsigned int val = (unsigned int)word; 337 338 return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask; 339 } 340 341 /** 342 * __fls - find last (most-significant) set bit in a long word 343 * @word: the word to search 344 * 345 * Undefined if no set bit exists, so code should check against 0 first. 346 */ 347 static inline unsigned long __fls(unsigned long word) 348 { 349 return __flogr(word) ^ (BITS_PER_LONG - 1); 350 } 351 352 /** 353 * fls64 - find last set bit in a 64-bit word 354 * @word: the word to search 355 * 356 * This is defined in a similar way as the libc and compiler builtin 357 * ffsll, but returns the position of the most significant set bit. 358 * 359 * fls64(value) returns 0 if value is 0 or the position of the last 360 * set bit if value is nonzero. The last (most significant) bit is 361 * at position 64. 362 */ 363 static inline int fls64(unsigned long word) 364 { 365 unsigned long mask = 2 * BITS_PER_LONG - 1; 366 367 return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask; 368 } 369 370 /** 371 * fls - find last (most-significant) bit set 372 * @word: the word to search 373 * 374 * This is defined the same way as ffs. 375 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. 376 */ 377 static inline int fls(unsigned int word) 378 { 379 return fls64(word); 380 } 381 382 #include <asm-generic/bitops/ffz.h> 383 #include <asm-generic/bitops/hweight.h> 384 #include <asm-generic/bitops/sched.h> 385 #include <asm-generic/bitops/le.h> 386 #include <asm-generic/bitops/ext2-atomic-setbit.h> 387 388 #endif /* _S390_BITOPS_H */ 389