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 <asm/atomic_ops.h> 39 #include <asm/barrier.h> 40 41 #define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG) 42 43 static inline unsigned long * 44 __bitops_word(unsigned long nr, volatile unsigned long *ptr) 45 { 46 unsigned long addr; 47 48 addr = (unsigned long)ptr + ((nr ^ (nr & (BITS_PER_LONG - 1))) >> 3); 49 return (unsigned long *)addr; 50 } 51 52 static inline unsigned char * 53 __bitops_byte(unsigned long nr, volatile unsigned long *ptr) 54 { 55 return ((unsigned char *)ptr) + ((nr ^ (BITS_PER_LONG - 8)) >> 3); 56 } 57 58 static inline void set_bit(unsigned long nr, volatile unsigned long *ptr) 59 { 60 unsigned long *addr = __bitops_word(nr, ptr); 61 unsigned long mask; 62 63 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 64 if (__builtin_constant_p(nr)) { 65 unsigned char *caddr = __bitops_byte(nr, ptr); 66 67 asm volatile( 68 "oi %0,%b1\n" 69 : "+Q" (*caddr) 70 : "i" (1 << (nr & 7)) 71 : "cc", "memory"); 72 return; 73 } 74 #endif 75 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 76 __atomic64_or(mask, (long *)addr); 77 } 78 79 static inline void clear_bit(unsigned long nr, volatile unsigned long *ptr) 80 { 81 unsigned long *addr = __bitops_word(nr, ptr); 82 unsigned long mask; 83 84 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 85 if (__builtin_constant_p(nr)) { 86 unsigned char *caddr = __bitops_byte(nr, ptr); 87 88 asm volatile( 89 "ni %0,%b1\n" 90 : "+Q" (*caddr) 91 : "i" (~(1 << (nr & 7))) 92 : "cc", "memory"); 93 return; 94 } 95 #endif 96 mask = ~(1UL << (nr & (BITS_PER_LONG - 1))); 97 __atomic64_and(mask, (long *)addr); 98 } 99 100 static inline void change_bit(unsigned long nr, volatile unsigned long *ptr) 101 { 102 unsigned long *addr = __bitops_word(nr, ptr); 103 unsigned long mask; 104 105 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 106 if (__builtin_constant_p(nr)) { 107 unsigned char *caddr = __bitops_byte(nr, ptr); 108 109 asm volatile( 110 "xi %0,%b1\n" 111 : "+Q" (*caddr) 112 : "i" (1 << (nr & 7)) 113 : "cc", "memory"); 114 return; 115 } 116 #endif 117 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 118 __atomic64_xor(mask, (long *)addr); 119 } 120 121 static inline int 122 test_and_set_bit(unsigned long nr, volatile unsigned long *ptr) 123 { 124 unsigned long *addr = __bitops_word(nr, ptr); 125 unsigned long old, mask; 126 127 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 128 old = __atomic64_or_barrier(mask, (long *)addr); 129 return (old & mask) != 0; 130 } 131 132 static inline int 133 test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr) 134 { 135 unsigned long *addr = __bitops_word(nr, ptr); 136 unsigned long old, mask; 137 138 mask = ~(1UL << (nr & (BITS_PER_LONG - 1))); 139 old = __atomic64_and_barrier(mask, (long *)addr); 140 return (old & ~mask) != 0; 141 } 142 143 static inline int 144 test_and_change_bit(unsigned long nr, volatile unsigned long *ptr) 145 { 146 unsigned long *addr = __bitops_word(nr, ptr); 147 unsigned long old, mask; 148 149 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 150 old = __atomic64_xor_barrier(mask, (long *)addr); 151 return (old & mask) != 0; 152 } 153 154 static inline void __set_bit(unsigned long nr, volatile unsigned long *ptr) 155 { 156 unsigned char *addr = __bitops_byte(nr, ptr); 157 158 *addr |= 1 << (nr & 7); 159 } 160 161 static inline void 162 __clear_bit(unsigned long nr, volatile unsigned long *ptr) 163 { 164 unsigned char *addr = __bitops_byte(nr, ptr); 165 166 *addr &= ~(1 << (nr & 7)); 167 } 168 169 static inline void __change_bit(unsigned long nr, volatile unsigned long *ptr) 170 { 171 unsigned char *addr = __bitops_byte(nr, ptr); 172 173 *addr ^= 1 << (nr & 7); 174 } 175 176 static inline int 177 __test_and_set_bit(unsigned long nr, volatile unsigned long *ptr) 178 { 179 unsigned char *addr = __bitops_byte(nr, ptr); 180 unsigned char ch; 181 182 ch = *addr; 183 *addr |= 1 << (nr & 7); 184 return (ch >> (nr & 7)) & 1; 185 } 186 187 static inline int 188 __test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr) 189 { 190 unsigned char *addr = __bitops_byte(nr, ptr); 191 unsigned char ch; 192 193 ch = *addr; 194 *addr &= ~(1 << (nr & 7)); 195 return (ch >> (nr & 7)) & 1; 196 } 197 198 static inline int 199 __test_and_change_bit(unsigned long nr, volatile unsigned long *ptr) 200 { 201 unsigned char *addr = __bitops_byte(nr, ptr); 202 unsigned char ch; 203 204 ch = *addr; 205 *addr ^= 1 << (nr & 7); 206 return (ch >> (nr & 7)) & 1; 207 } 208 209 static inline int test_bit(unsigned long nr, const volatile unsigned long *ptr) 210 { 211 const volatile unsigned char *addr; 212 213 addr = ((const volatile unsigned char *)ptr); 214 addr += (nr ^ (BITS_PER_LONG - 8)) >> 3; 215 return (*addr >> (nr & 7)) & 1; 216 } 217 218 static inline int test_and_set_bit_lock(unsigned long nr, 219 volatile unsigned long *ptr) 220 { 221 if (test_bit(nr, ptr)) 222 return 1; 223 return test_and_set_bit(nr, ptr); 224 } 225 226 static inline void clear_bit_unlock(unsigned long nr, 227 volatile unsigned long *ptr) 228 { 229 smp_mb__before_atomic(); 230 clear_bit(nr, ptr); 231 } 232 233 static inline void __clear_bit_unlock(unsigned long nr, 234 volatile unsigned long *ptr) 235 { 236 smp_mb(); 237 __clear_bit(nr, ptr); 238 } 239 240 /* 241 * Functions which use MSB0 bit numbering. 242 * The bits are numbered: 243 * |0..............63|64............127|128...........191|192...........255| 244 */ 245 unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size); 246 unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size, 247 unsigned long offset); 248 249 #define for_each_set_bit_inv(bit, addr, size) \ 250 for ((bit) = find_first_bit_inv((addr), (size)); \ 251 (bit) < (size); \ 252 (bit) = find_next_bit_inv((addr), (size), (bit) + 1)) 253 254 static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 255 { 256 return set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 257 } 258 259 static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 260 { 261 return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 262 } 263 264 static inline int test_and_clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 265 { 266 return test_and_clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 267 } 268 269 static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 270 { 271 return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 272 } 273 274 static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 275 { 276 return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 277 } 278 279 static inline int test_bit_inv(unsigned long nr, 280 const volatile unsigned long *ptr) 281 { 282 return test_bit(nr ^ (BITS_PER_LONG - 1), ptr); 283 } 284 285 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES 286 287 /** 288 * __flogr - find leftmost one 289 * @word - The word to search 290 * 291 * Returns the bit number of the most significant bit set, 292 * where the most significant bit has bit number 0. 293 * If no bit is set this function returns 64. 294 */ 295 static inline unsigned char __flogr(unsigned long word) 296 { 297 if (__builtin_constant_p(word)) { 298 unsigned long bit = 0; 299 300 if (!word) 301 return 64; 302 if (!(word & 0xffffffff00000000UL)) { 303 word <<= 32; 304 bit += 32; 305 } 306 if (!(word & 0xffff000000000000UL)) { 307 word <<= 16; 308 bit += 16; 309 } 310 if (!(word & 0xff00000000000000UL)) { 311 word <<= 8; 312 bit += 8; 313 } 314 if (!(word & 0xf000000000000000UL)) { 315 word <<= 4; 316 bit += 4; 317 } 318 if (!(word & 0xc000000000000000UL)) { 319 word <<= 2; 320 bit += 2; 321 } 322 if (!(word & 0x8000000000000000UL)) { 323 word <<= 1; 324 bit += 1; 325 } 326 return bit; 327 } else { 328 register unsigned long bit asm("4") = word; 329 register unsigned long out asm("5"); 330 331 asm volatile( 332 " flogr %[bit],%[bit]\n" 333 : [bit] "+d" (bit), [out] "=d" (out) : : "cc"); 334 return bit; 335 } 336 } 337 338 /** 339 * __ffs - find first bit in word. 340 * @word: The word to search 341 * 342 * Undefined if no bit exists, so code should check against 0 first. 343 */ 344 static inline unsigned long __ffs(unsigned long word) 345 { 346 return __flogr(-word & word) ^ (BITS_PER_LONG - 1); 347 } 348 349 /** 350 * ffs - find first bit set 351 * @word: the word to search 352 * 353 * This is defined the same way as the libc and 354 * compiler builtin ffs routines (man ffs). 355 */ 356 static inline int ffs(int word) 357 { 358 unsigned long mask = 2 * BITS_PER_LONG - 1; 359 unsigned int val = (unsigned int)word; 360 361 return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask; 362 } 363 364 /** 365 * __fls - find last (most-significant) set bit in a long word 366 * @word: the word to search 367 * 368 * Undefined if no set bit exists, so code should check against 0 first. 369 */ 370 static inline unsigned long __fls(unsigned long word) 371 { 372 return __flogr(word) ^ (BITS_PER_LONG - 1); 373 } 374 375 /** 376 * fls64 - find last set bit in a 64-bit word 377 * @word: the word to search 378 * 379 * This is defined in a similar way as the libc and compiler builtin 380 * ffsll, but returns the position of the most significant set bit. 381 * 382 * fls64(value) returns 0 if value is 0 or the position of the last 383 * set bit if value is nonzero. The last (most significant) bit is 384 * at position 64. 385 */ 386 static inline int fls64(unsigned long word) 387 { 388 unsigned long mask = 2 * BITS_PER_LONG - 1; 389 390 return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask; 391 } 392 393 /** 394 * fls - find last (most-significant) bit set 395 * @word: the word to search 396 * 397 * This is defined the same way as ffs. 398 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. 399 */ 400 static inline int fls(unsigned int word) 401 { 402 return fls64(word); 403 } 404 405 #else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */ 406 407 #include <asm-generic/bitops/__ffs.h> 408 #include <asm-generic/bitops/ffs.h> 409 #include <asm-generic/bitops/__fls.h> 410 #include <asm-generic/bitops/fls.h> 411 #include <asm-generic/bitops/fls64.h> 412 413 #endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */ 414 415 #include <asm-generic/bitops/ffz.h> 416 #include <asm-generic/bitops/find.h> 417 #include <asm-generic/bitops/hweight.h> 418 #include <asm-generic/bitops/sched.h> 419 #include <asm-generic/bitops/le.h> 420 #include <asm-generic/bitops/ext2-atomic-setbit.h> 421 422 #endif /* _S390_BITOPS_H */ 423