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, 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 char * 54 __bitops_byte(unsigned long nr, volatile unsigned long *ptr) 55 { 56 return ((unsigned char *)ptr) + ((nr ^ (BITS_PER_LONG - 8)) >> 3); 57 } 58 59 static __always_inline void arch_set_bit(unsigned long nr, volatile unsigned long *ptr) 60 { 61 unsigned long *addr = __bitops_word(nr, ptr); 62 unsigned long mask; 63 64 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 65 if (__builtin_constant_p(nr)) { 66 unsigned char *caddr = __bitops_byte(nr, ptr); 67 68 asm volatile( 69 "oi %0,%b1\n" 70 : "+Q" (*caddr) 71 : "i" (1 << (nr & 7)) 72 : "cc", "memory"); 73 return; 74 } 75 #endif 76 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 77 __atomic64_or(mask, (long *)addr); 78 } 79 80 static __always_inline void arch_clear_bit(unsigned long nr, volatile unsigned long *ptr) 81 { 82 unsigned long *addr = __bitops_word(nr, ptr); 83 unsigned long mask; 84 85 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 86 if (__builtin_constant_p(nr)) { 87 unsigned char *caddr = __bitops_byte(nr, ptr); 88 89 asm volatile( 90 "ni %0,%b1\n" 91 : "+Q" (*caddr) 92 : "i" (~(1 << (nr & 7))) 93 : "cc", "memory"); 94 return; 95 } 96 #endif 97 mask = ~(1UL << (nr & (BITS_PER_LONG - 1))); 98 __atomic64_and(mask, (long *)addr); 99 } 100 101 static __always_inline void arch_change_bit(unsigned long nr, 102 volatile unsigned long *ptr) 103 { 104 unsigned long *addr = __bitops_word(nr, ptr); 105 unsigned long mask; 106 107 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 108 if (__builtin_constant_p(nr)) { 109 unsigned char *caddr = __bitops_byte(nr, ptr); 110 111 asm volatile( 112 "xi %0,%b1\n" 113 : "+Q" (*caddr) 114 : "i" (1 << (nr & 7)) 115 : "cc", "memory"); 116 return; 117 } 118 #endif 119 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 120 __atomic64_xor(mask, (long *)addr); 121 } 122 123 static inline bool arch_test_and_set_bit(unsigned long nr, 124 volatile unsigned long *ptr) 125 { 126 unsigned long *addr = __bitops_word(nr, ptr); 127 unsigned long old, mask; 128 129 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 130 old = __atomic64_or_barrier(mask, (long *)addr); 131 return (old & mask) != 0; 132 } 133 134 static inline bool arch_test_and_clear_bit(unsigned long nr, 135 volatile unsigned long *ptr) 136 { 137 unsigned long *addr = __bitops_word(nr, ptr); 138 unsigned long old, mask; 139 140 mask = ~(1UL << (nr & (BITS_PER_LONG - 1))); 141 old = __atomic64_and_barrier(mask, (long *)addr); 142 return (old & ~mask) != 0; 143 } 144 145 static inline bool arch_test_and_change_bit(unsigned long nr, 146 volatile unsigned long *ptr) 147 { 148 unsigned long *addr = __bitops_word(nr, ptr); 149 unsigned long old, mask; 150 151 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 152 old = __atomic64_xor_barrier(mask, (long *)addr); 153 return (old & mask) != 0; 154 } 155 156 static inline void arch___set_bit(unsigned long nr, volatile unsigned long *ptr) 157 { 158 unsigned char *addr = __bitops_byte(nr, ptr); 159 160 *addr |= 1 << (nr & 7); 161 } 162 163 static inline void arch___clear_bit(unsigned long nr, 164 volatile unsigned long *ptr) 165 { 166 unsigned char *addr = __bitops_byte(nr, ptr); 167 168 *addr &= ~(1 << (nr & 7)); 169 } 170 171 static inline void arch___change_bit(unsigned long nr, 172 volatile unsigned long *ptr) 173 { 174 unsigned char *addr = __bitops_byte(nr, ptr); 175 176 *addr ^= 1 << (nr & 7); 177 } 178 179 static inline bool arch___test_and_set_bit(unsigned long nr, 180 volatile unsigned long *ptr) 181 { 182 unsigned char *addr = __bitops_byte(nr, ptr); 183 unsigned char ch; 184 185 ch = *addr; 186 *addr |= 1 << (nr & 7); 187 return (ch >> (nr & 7)) & 1; 188 } 189 190 static inline bool arch___test_and_clear_bit(unsigned long nr, 191 volatile unsigned long *ptr) 192 { 193 unsigned char *addr = __bitops_byte(nr, ptr); 194 unsigned char ch; 195 196 ch = *addr; 197 *addr &= ~(1 << (nr & 7)); 198 return (ch >> (nr & 7)) & 1; 199 } 200 201 static inline bool arch___test_and_change_bit(unsigned long nr, 202 volatile unsigned long *ptr) 203 { 204 unsigned char *addr = __bitops_byte(nr, ptr); 205 unsigned char ch; 206 207 ch = *addr; 208 *addr ^= 1 << (nr & 7); 209 return (ch >> (nr & 7)) & 1; 210 } 211 212 static inline bool arch_test_bit(unsigned long nr, 213 const volatile unsigned long *ptr) 214 { 215 const volatile unsigned char *addr; 216 217 addr = ((const volatile unsigned char *)ptr); 218 addr += (nr ^ (BITS_PER_LONG - 8)) >> 3; 219 return (*addr >> (nr & 7)) & 1; 220 } 221 222 static inline bool arch_test_and_set_bit_lock(unsigned long nr, 223 volatile unsigned long *ptr) 224 { 225 if (arch_test_bit(nr, ptr)) 226 return 1; 227 return arch_test_and_set_bit(nr, ptr); 228 } 229 230 static inline void arch_clear_bit_unlock(unsigned long nr, 231 volatile unsigned long *ptr) 232 { 233 smp_mb__before_atomic(); 234 arch_clear_bit(nr, ptr); 235 } 236 237 static inline void arch___clear_bit_unlock(unsigned long nr, 238 volatile unsigned long *ptr) 239 { 240 smp_mb(); 241 arch___clear_bit(nr, ptr); 242 } 243 244 #include <asm-generic/bitops-instrumented.h> 245 246 /* 247 * Functions which use MSB0 bit numbering. 248 * The bits are numbered: 249 * |0..............63|64............127|128...........191|192...........255| 250 */ 251 unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size); 252 unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size, 253 unsigned long offset); 254 255 #define for_each_set_bit_inv(bit, addr, size) \ 256 for ((bit) = find_first_bit_inv((addr), (size)); \ 257 (bit) < (size); \ 258 (bit) = find_next_bit_inv((addr), (size), (bit) + 1)) 259 260 static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 261 { 262 return set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 263 } 264 265 static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 266 { 267 return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 268 } 269 270 static inline bool test_and_clear_bit_inv(unsigned long nr, 271 volatile unsigned long *ptr) 272 { 273 return test_and_clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 274 } 275 276 static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 277 { 278 return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 279 } 280 281 static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 282 { 283 return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 284 } 285 286 static inline bool test_bit_inv(unsigned long nr, 287 const volatile unsigned long *ptr) 288 { 289 return test_bit(nr ^ (BITS_PER_LONG - 1), ptr); 290 } 291 292 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES 293 294 /** 295 * __flogr - find leftmost one 296 * @word - The word to search 297 * 298 * Returns the bit number of the most significant bit set, 299 * where the most significant bit has bit number 0. 300 * If no bit is set this function returns 64. 301 */ 302 static inline unsigned char __flogr(unsigned long word) 303 { 304 if (__builtin_constant_p(word)) { 305 unsigned long bit = 0; 306 307 if (!word) 308 return 64; 309 if (!(word & 0xffffffff00000000UL)) { 310 word <<= 32; 311 bit += 32; 312 } 313 if (!(word & 0xffff000000000000UL)) { 314 word <<= 16; 315 bit += 16; 316 } 317 if (!(word & 0xff00000000000000UL)) { 318 word <<= 8; 319 bit += 8; 320 } 321 if (!(word & 0xf000000000000000UL)) { 322 word <<= 4; 323 bit += 4; 324 } 325 if (!(word & 0xc000000000000000UL)) { 326 word <<= 2; 327 bit += 2; 328 } 329 if (!(word & 0x8000000000000000UL)) { 330 word <<= 1; 331 bit += 1; 332 } 333 return bit; 334 } else { 335 register unsigned long bit asm("4") = word; 336 register unsigned long out asm("5"); 337 338 asm volatile( 339 " flogr %[bit],%[bit]\n" 340 : [bit] "+d" (bit), [out] "=d" (out) : : "cc"); 341 return bit; 342 } 343 } 344 345 /** 346 * __ffs - find first bit in word. 347 * @word: The word to search 348 * 349 * Undefined if no bit exists, so code should check against 0 first. 350 */ 351 static inline unsigned long __ffs(unsigned long word) 352 { 353 return __flogr(-word & word) ^ (BITS_PER_LONG - 1); 354 } 355 356 /** 357 * ffs - find first bit set 358 * @word: the word to search 359 * 360 * This is defined the same way as the libc and 361 * compiler builtin ffs routines (man ffs). 362 */ 363 static inline int ffs(int word) 364 { 365 unsigned long mask = 2 * BITS_PER_LONG - 1; 366 unsigned int val = (unsigned int)word; 367 368 return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask; 369 } 370 371 /** 372 * __fls - find last (most-significant) set bit in a long word 373 * @word: the word to search 374 * 375 * Undefined if no set bit exists, so code should check against 0 first. 376 */ 377 static inline unsigned long __fls(unsigned long word) 378 { 379 return __flogr(word) ^ (BITS_PER_LONG - 1); 380 } 381 382 /** 383 * fls64 - find last set bit in a 64-bit word 384 * @word: the word to search 385 * 386 * This is defined in a similar way as the libc and compiler builtin 387 * ffsll, but returns the position of the most significant set bit. 388 * 389 * fls64(value) returns 0 if value is 0 or the position of the last 390 * set bit if value is nonzero. The last (most significant) bit is 391 * at position 64. 392 */ 393 static inline int fls64(unsigned long word) 394 { 395 unsigned long mask = 2 * BITS_PER_LONG - 1; 396 397 return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask; 398 } 399 400 /** 401 * fls - find last (most-significant) bit set 402 * @word: the word to search 403 * 404 * This is defined the same way as ffs. 405 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. 406 */ 407 static inline int fls(unsigned int word) 408 { 409 return fls64(word); 410 } 411 412 #else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */ 413 414 #include <asm-generic/bitops/__ffs.h> 415 #include <asm-generic/bitops/ffs.h> 416 #include <asm-generic/bitops/__fls.h> 417 #include <asm-generic/bitops/fls.h> 418 #include <asm-generic/bitops/fls64.h> 419 420 #endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */ 421 422 #include <asm-generic/bitops/ffz.h> 423 #include <asm-generic/bitops/find.h> 424 #include <asm-generic/bitops/hweight.h> 425 #include <asm-generic/bitops/sched.h> 426 #include <asm-generic/bitops/le.h> 427 #include <asm-generic/bitops/ext2-atomic-setbit.h> 428 429 #endif /* _S390_BITOPS_H */ 430