1 /* 2 * Copyright IBM Corp. 1999,2013 3 * 4 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>, 5 * 6 * The description below was taken in large parts from the powerpc 7 * bitops header file: 8 * Within a word, bits are numbered LSB first. Lot's of places make 9 * this assumption by directly testing bits with (val & (1<<nr)). 10 * This can cause confusion for large (> 1 word) bitmaps on a 11 * big-endian system because, unlike little endian, the number of each 12 * bit depends on the word size. 13 * 14 * The bitop functions are defined to work on unsigned longs, so the bits 15 * end up numbered: 16 * |63..............0|127............64|191...........128|255...........192| 17 * 18 * We also have special functions which work with an MSB0 encoding. 19 * The bits are numbered: 20 * |0..............63|64............127|128...........191|192...........255| 21 * 22 * The main difference is that bit 0-63 in the bit number field needs to be 23 * reversed compared to the LSB0 encoded bit fields. This can be achieved by 24 * XOR with 0x3f. 25 * 26 */ 27 28 #ifndef _S390_BITOPS_H 29 #define _S390_BITOPS_H 30 31 #ifndef _LINUX_BITOPS_H 32 #error only <linux/bitops.h> can be included directly 33 #endif 34 35 #include <linux/typecheck.h> 36 #include <linux/compiler.h> 37 #include <asm/atomic_ops.h> 38 #include <asm/barrier.h> 39 40 #define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG) 41 42 static inline unsigned long * 43 __bitops_word(unsigned long nr, volatile unsigned long *ptr) 44 { 45 unsigned long addr; 46 47 addr = (unsigned long)ptr + ((nr ^ (nr & (BITS_PER_LONG - 1))) >> 3); 48 return (unsigned long *)addr; 49 } 50 51 static inline unsigned char * 52 __bitops_byte(unsigned long nr, volatile unsigned long *ptr) 53 { 54 return ((unsigned char *)ptr) + ((nr ^ (BITS_PER_LONG - 8)) >> 3); 55 } 56 57 static inline void set_bit(unsigned long nr, volatile unsigned long *ptr) 58 { 59 unsigned long *addr = __bitops_word(nr, ptr); 60 unsigned long mask; 61 62 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 63 if (__builtin_constant_p(nr)) { 64 unsigned char *caddr = __bitops_byte(nr, ptr); 65 66 asm volatile( 67 "oi %0,%b1\n" 68 : "+Q" (*caddr) 69 : "i" (1 << (nr & 7)) 70 : "cc", "memory"); 71 return; 72 } 73 #endif 74 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 75 __atomic64_or(mask, addr); 76 } 77 78 static inline void clear_bit(unsigned long nr, volatile unsigned long *ptr) 79 { 80 unsigned long *addr = __bitops_word(nr, ptr); 81 unsigned long mask; 82 83 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 84 if (__builtin_constant_p(nr)) { 85 unsigned char *caddr = __bitops_byte(nr, ptr); 86 87 asm volatile( 88 "ni %0,%b1\n" 89 : "+Q" (*caddr) 90 : "i" (~(1 << (nr & 7))) 91 : "cc", "memory"); 92 return; 93 } 94 #endif 95 mask = ~(1UL << (nr & (BITS_PER_LONG - 1))); 96 __atomic64_and(mask, addr); 97 } 98 99 static inline void change_bit(unsigned long nr, volatile unsigned long *ptr) 100 { 101 unsigned long *addr = __bitops_word(nr, ptr); 102 unsigned long mask; 103 104 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 105 if (__builtin_constant_p(nr)) { 106 unsigned char *caddr = __bitops_byte(nr, ptr); 107 108 asm volatile( 109 "xi %0,%b1\n" 110 : "+Q" (*caddr) 111 : "i" (1 << (nr & 7)) 112 : "cc", "memory"); 113 return; 114 } 115 #endif 116 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 117 __atomic64_xor(mask, addr); 118 } 119 120 static inline int 121 test_and_set_bit(unsigned long nr, volatile unsigned long *ptr) 122 { 123 unsigned long *addr = __bitops_word(nr, ptr); 124 unsigned long old, mask; 125 126 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 127 old = __atomic64_or_barrier(mask, addr); 128 return (old & mask) != 0; 129 } 130 131 static inline int 132 test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr) 133 { 134 unsigned long *addr = __bitops_word(nr, ptr); 135 unsigned long old, mask; 136 137 mask = ~(1UL << (nr & (BITS_PER_LONG - 1))); 138 old = __atomic64_and_barrier(mask, addr); 139 return (old & ~mask) != 0; 140 } 141 142 static inline int 143 test_and_change_bit(unsigned long nr, volatile unsigned long *ptr) 144 { 145 unsigned long *addr = __bitops_word(nr, ptr); 146 unsigned long old, mask; 147 148 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 149 old = __atomic64_xor_barrier(mask, addr); 150 return (old & mask) != 0; 151 } 152 153 static inline void __set_bit(unsigned long nr, volatile unsigned long *ptr) 154 { 155 unsigned char *addr = __bitops_byte(nr, ptr); 156 157 *addr |= 1 << (nr & 7); 158 } 159 160 static inline void 161 __clear_bit(unsigned long nr, volatile unsigned long *ptr) 162 { 163 unsigned char *addr = __bitops_byte(nr, ptr); 164 165 *addr &= ~(1 << (nr & 7)); 166 } 167 168 static inline void __change_bit(unsigned long nr, volatile unsigned long *ptr) 169 { 170 unsigned char *addr = __bitops_byte(nr, ptr); 171 172 *addr ^= 1 << (nr & 7); 173 } 174 175 static inline int 176 __test_and_set_bit(unsigned long nr, volatile unsigned long *ptr) 177 { 178 unsigned char *addr = __bitops_byte(nr, ptr); 179 unsigned char ch; 180 181 ch = *addr; 182 *addr |= 1 << (nr & 7); 183 return (ch >> (nr & 7)) & 1; 184 } 185 186 static inline int 187 __test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr) 188 { 189 unsigned char *addr = __bitops_byte(nr, ptr); 190 unsigned char ch; 191 192 ch = *addr; 193 *addr &= ~(1 << (nr & 7)); 194 return (ch >> (nr & 7)) & 1; 195 } 196 197 static inline int 198 __test_and_change_bit(unsigned long nr, volatile unsigned long *ptr) 199 { 200 unsigned char *addr = __bitops_byte(nr, ptr); 201 unsigned char ch; 202 203 ch = *addr; 204 *addr ^= 1 << (nr & 7); 205 return (ch >> (nr & 7)) & 1; 206 } 207 208 static inline int test_bit(unsigned long nr, const volatile unsigned long *ptr) 209 { 210 const volatile unsigned char *addr; 211 212 addr = ((const volatile unsigned char *)ptr); 213 addr += (nr ^ (BITS_PER_LONG - 8)) >> 3; 214 return (*addr >> (nr & 7)) & 1; 215 } 216 217 static inline int test_and_set_bit_lock(unsigned long nr, 218 volatile unsigned long *ptr) 219 { 220 if (test_bit(nr, ptr)) 221 return 1; 222 return test_and_set_bit(nr, ptr); 223 } 224 225 static inline void clear_bit_unlock(unsigned long nr, 226 volatile unsigned long *ptr) 227 { 228 smp_mb__before_atomic(); 229 clear_bit(nr, ptr); 230 } 231 232 static inline void __clear_bit_unlock(unsigned long nr, 233 volatile unsigned long *ptr) 234 { 235 smp_mb(); 236 __clear_bit(nr, ptr); 237 } 238 239 /* 240 * Functions which use MSB0 bit numbering. 241 * The bits are numbered: 242 * |0..............63|64............127|128...........191|192...........255| 243 */ 244 unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size); 245 unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size, 246 unsigned long offset); 247 248 #define for_each_set_bit_inv(bit, addr, size) \ 249 for ((bit) = find_first_bit_inv((addr), (size)); \ 250 (bit) < (size); \ 251 (bit) = find_next_bit_inv((addr), (size), (bit) + 1)) 252 253 static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 254 { 255 return set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 256 } 257 258 static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 259 { 260 return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 261 } 262 263 static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 264 { 265 return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 266 } 267 268 static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 269 { 270 return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 271 } 272 273 static inline int test_bit_inv(unsigned long nr, 274 const volatile unsigned long *ptr) 275 { 276 return test_bit(nr ^ (BITS_PER_LONG - 1), ptr); 277 } 278 279 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES 280 281 /** 282 * __flogr - find leftmost one 283 * @word - The word to search 284 * 285 * Returns the bit number of the most significant bit set, 286 * where the most significant bit has bit number 0. 287 * If no bit is set this function returns 64. 288 */ 289 static inline unsigned char __flogr(unsigned long word) 290 { 291 if (__builtin_constant_p(word)) { 292 unsigned long bit = 0; 293 294 if (!word) 295 return 64; 296 if (!(word & 0xffffffff00000000UL)) { 297 word <<= 32; 298 bit += 32; 299 } 300 if (!(word & 0xffff000000000000UL)) { 301 word <<= 16; 302 bit += 16; 303 } 304 if (!(word & 0xff00000000000000UL)) { 305 word <<= 8; 306 bit += 8; 307 } 308 if (!(word & 0xf000000000000000UL)) { 309 word <<= 4; 310 bit += 4; 311 } 312 if (!(word & 0xc000000000000000UL)) { 313 word <<= 2; 314 bit += 2; 315 } 316 if (!(word & 0x8000000000000000UL)) { 317 word <<= 1; 318 bit += 1; 319 } 320 return bit; 321 } else { 322 register unsigned long bit asm("4") = word; 323 register unsigned long out asm("5"); 324 325 asm volatile( 326 " flogr %[bit],%[bit]\n" 327 : [bit] "+d" (bit), [out] "=d" (out) : : "cc"); 328 return bit; 329 } 330 } 331 332 /** 333 * __ffs - find first bit in word. 334 * @word: The word to search 335 * 336 * Undefined if no bit exists, so code should check against 0 first. 337 */ 338 static inline unsigned long __ffs(unsigned long word) 339 { 340 return __flogr(-word & word) ^ (BITS_PER_LONG - 1); 341 } 342 343 /** 344 * ffs - find first bit set 345 * @word: the word to search 346 * 347 * This is defined the same way as the libc and 348 * compiler builtin ffs routines (man ffs). 349 */ 350 static inline int ffs(int word) 351 { 352 unsigned long mask = 2 * BITS_PER_LONG - 1; 353 unsigned int val = (unsigned int)word; 354 355 return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask; 356 } 357 358 /** 359 * __fls - find last (most-significant) set bit in a long word 360 * @word: the word to search 361 * 362 * Undefined if no set bit exists, so code should check against 0 first. 363 */ 364 static inline unsigned long __fls(unsigned long word) 365 { 366 return __flogr(word) ^ (BITS_PER_LONG - 1); 367 } 368 369 /** 370 * fls64 - find last set bit in a 64-bit word 371 * @word: the word to search 372 * 373 * This is defined in a similar way as the libc and compiler builtin 374 * ffsll, but returns the position of the most significant set bit. 375 * 376 * fls64(value) returns 0 if value is 0 or the position of the last 377 * set bit if value is nonzero. The last (most significant) bit is 378 * at position 64. 379 */ 380 static inline int fls64(unsigned long word) 381 { 382 unsigned long mask = 2 * BITS_PER_LONG - 1; 383 384 return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask; 385 } 386 387 /** 388 * fls - find last (most-significant) bit set 389 * @word: the word to search 390 * 391 * This is defined the same way as ffs. 392 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. 393 */ 394 static inline int fls(int word) 395 { 396 return fls64((unsigned int)word); 397 } 398 399 #else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */ 400 401 #include <asm-generic/bitops/__ffs.h> 402 #include <asm-generic/bitops/ffs.h> 403 #include <asm-generic/bitops/__fls.h> 404 #include <asm-generic/bitops/fls.h> 405 #include <asm-generic/bitops/fls64.h> 406 407 #endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */ 408 409 #include <asm-generic/bitops/ffz.h> 410 #include <asm-generic/bitops/find.h> 411 #include <asm-generic/bitops/hweight.h> 412 #include <asm-generic/bitops/sched.h> 413 #include <asm-generic/bitops/le.h> 414 #include <asm-generic/bitops/ext2-atomic-setbit.h> 415 416 #endif /* _S390_BITOPS_H */ 417