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 * There are a few little-endian macros used mostly for filesystem 19 * bitmaps, these work on similar bit array layouts, but byte-oriented: 20 * |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56| 21 * 22 * The main difference is that bit 3-5 in the bit number field needs to be 23 * reversed compared to the big-endian bit fields. This can be achieved by 24 * XOR with 0x38. 25 * 26 * We also have special functions which work with an MSB0 encoding. 27 * The bits are numbered: 28 * |0..............63|64............127|128...........191|192...........255| 29 * 30 * The main difference is that bit 0-63 in the bit number field needs to be 31 * reversed compared to the LSB0 encoded bit fields. This can be achieved by 32 * XOR with 0x3f. 33 * 34 */ 35 36 #ifndef _S390_BITOPS_H 37 #define _S390_BITOPS_H 38 39 #ifndef _LINUX_BITOPS_H 40 #error only <linux/bitops.h> can be included directly 41 #endif 42 43 #include <linux/typecheck.h> 44 #include <linux/compiler.h> 45 #include <asm/atomic_ops.h> 46 #include <asm/barrier.h> 47 48 #define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG) 49 50 static inline unsigned long * 51 __bitops_word(unsigned long nr, volatile unsigned long *ptr) 52 { 53 unsigned long addr; 54 55 addr = (unsigned long)ptr + ((nr ^ (nr & (BITS_PER_LONG - 1))) >> 3); 56 return (unsigned long *)addr; 57 } 58 59 static inline unsigned char * 60 __bitops_byte(unsigned long nr, volatile unsigned long *ptr) 61 { 62 return ((unsigned char *)ptr) + ((nr ^ (BITS_PER_LONG - 8)) >> 3); 63 } 64 65 static inline void set_bit(unsigned long nr, volatile unsigned long *ptr) 66 { 67 unsigned long *addr = __bitops_word(nr, ptr); 68 unsigned long mask; 69 70 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 71 if (__builtin_constant_p(nr)) { 72 unsigned char *caddr = __bitops_byte(nr, ptr); 73 74 asm volatile( 75 "oi %0,%b1\n" 76 : "+Q" (*caddr) 77 : "i" (1 << (nr & 7)) 78 : "cc", "memory"); 79 return; 80 } 81 #endif 82 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 83 __atomic64_or(mask, addr); 84 } 85 86 static inline void clear_bit(unsigned long nr, volatile unsigned long *ptr) 87 { 88 unsigned long *addr = __bitops_word(nr, ptr); 89 unsigned long mask; 90 91 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 92 if (__builtin_constant_p(nr)) { 93 unsigned char *caddr = __bitops_byte(nr, ptr); 94 95 asm volatile( 96 "ni %0,%b1\n" 97 : "+Q" (*caddr) 98 : "i" (~(1 << (nr & 7))) 99 : "cc", "memory"); 100 return; 101 } 102 #endif 103 mask = ~(1UL << (nr & (BITS_PER_LONG - 1))); 104 __atomic64_and(mask, addr); 105 } 106 107 static inline void change_bit(unsigned long nr, volatile unsigned long *ptr) 108 { 109 unsigned long *addr = __bitops_word(nr, ptr); 110 unsigned long mask; 111 112 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES 113 if (__builtin_constant_p(nr)) { 114 unsigned char *caddr = __bitops_byte(nr, ptr); 115 116 asm volatile( 117 "xi %0,%b1\n" 118 : "+Q" (*caddr) 119 : "i" (1 << (nr & 7)) 120 : "cc", "memory"); 121 return; 122 } 123 #endif 124 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 125 __atomic64_xor(mask, addr); 126 } 127 128 static inline int 129 test_and_set_bit(unsigned long nr, volatile unsigned long *ptr) 130 { 131 unsigned long *addr = __bitops_word(nr, ptr); 132 unsigned long old, mask; 133 134 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 135 old = __atomic64_or_barrier(mask, addr); 136 return (old & mask) != 0; 137 } 138 139 static inline int 140 test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr) 141 { 142 unsigned long *addr = __bitops_word(nr, ptr); 143 unsigned long old, mask; 144 145 mask = ~(1UL << (nr & (BITS_PER_LONG - 1))); 146 old = __atomic64_and_barrier(mask, addr); 147 return (old & ~mask) != 0; 148 } 149 150 static inline int 151 test_and_change_bit(unsigned long nr, volatile unsigned long *ptr) 152 { 153 unsigned long *addr = __bitops_word(nr, ptr); 154 unsigned long old, mask; 155 156 mask = 1UL << (nr & (BITS_PER_LONG - 1)); 157 old = __atomic64_xor_barrier(mask, addr); 158 return (old & mask) != 0; 159 } 160 161 static inline void __set_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 169 __clear_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 void __change_bit(unsigned long nr, volatile unsigned long *ptr) 177 { 178 unsigned char *addr = __bitops_byte(nr, ptr); 179 180 *addr ^= 1 << (nr & 7); 181 } 182 183 static inline int 184 __test_and_set_bit(unsigned long nr, volatile unsigned long *ptr) 185 { 186 unsigned char *addr = __bitops_byte(nr, ptr); 187 unsigned char ch; 188 189 ch = *addr; 190 *addr |= 1 << (nr & 7); 191 return (ch >> (nr & 7)) & 1; 192 } 193 194 static inline int 195 __test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr) 196 { 197 unsigned char *addr = __bitops_byte(nr, ptr); 198 unsigned char ch; 199 200 ch = *addr; 201 *addr &= ~(1 << (nr & 7)); 202 return (ch >> (nr & 7)) & 1; 203 } 204 205 static inline int 206 __test_and_change_bit(unsigned long nr, volatile unsigned long *ptr) 207 { 208 unsigned char *addr = __bitops_byte(nr, ptr); 209 unsigned char ch; 210 211 ch = *addr; 212 *addr ^= 1 << (nr & 7); 213 return (ch >> (nr & 7)) & 1; 214 } 215 216 static inline int test_bit(unsigned long nr, const volatile unsigned long *ptr) 217 { 218 const volatile unsigned char *addr; 219 220 addr = ((const volatile unsigned char *)ptr); 221 addr += (nr ^ (BITS_PER_LONG - 8)) >> 3; 222 return (*addr >> (nr & 7)) & 1; 223 } 224 225 static inline int test_and_set_bit_lock(unsigned long nr, 226 volatile unsigned long *ptr) 227 { 228 if (test_bit(nr, ptr)) 229 return 1; 230 return test_and_set_bit(nr, ptr); 231 } 232 233 static inline void clear_bit_unlock(unsigned long nr, 234 volatile unsigned long *ptr) 235 { 236 smp_mb__before_atomic(); 237 clear_bit(nr, ptr); 238 } 239 240 static inline void __clear_bit_unlock(unsigned long nr, 241 volatile unsigned long *ptr) 242 { 243 smp_mb(); 244 __clear_bit(nr, ptr); 245 } 246 247 /* 248 * Functions which use MSB0 bit numbering. 249 * The bits are numbered: 250 * |0..............63|64............127|128...........191|192...........255| 251 */ 252 unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size); 253 unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size, 254 unsigned long offset); 255 256 static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 257 { 258 return set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 259 } 260 261 static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 262 { 263 return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 264 } 265 266 static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr) 267 { 268 return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr); 269 } 270 271 static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr) 272 { 273 return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr); 274 } 275 276 static inline int test_bit_inv(unsigned long nr, 277 const volatile unsigned long *ptr) 278 { 279 return test_bit(nr ^ (BITS_PER_LONG - 1), ptr); 280 } 281 282 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES 283 284 /** 285 * __flogr - find leftmost one 286 * @word - The word to search 287 * 288 * Returns the bit number of the most significant bit set, 289 * where the most significant bit has bit number 0. 290 * If no bit is set this function returns 64. 291 */ 292 static inline unsigned char __flogr(unsigned long word) 293 { 294 if (__builtin_constant_p(word)) { 295 unsigned long bit = 0; 296 297 if (!word) 298 return 64; 299 if (!(word & 0xffffffff00000000UL)) { 300 word <<= 32; 301 bit += 32; 302 } 303 if (!(word & 0xffff000000000000UL)) { 304 word <<= 16; 305 bit += 16; 306 } 307 if (!(word & 0xff00000000000000UL)) { 308 word <<= 8; 309 bit += 8; 310 } 311 if (!(word & 0xf000000000000000UL)) { 312 word <<= 4; 313 bit += 4; 314 } 315 if (!(word & 0xc000000000000000UL)) { 316 word <<= 2; 317 bit += 2; 318 } 319 if (!(word & 0x8000000000000000UL)) { 320 word <<= 1; 321 bit += 1; 322 } 323 return bit; 324 } else { 325 register unsigned long bit asm("4") = word; 326 register unsigned long out asm("5"); 327 328 asm volatile( 329 " flogr %[bit],%[bit]\n" 330 : [bit] "+d" (bit), [out] "=d" (out) : : "cc"); 331 return bit; 332 } 333 } 334 335 /** 336 * __ffs - find first bit in word. 337 * @word: The word to search 338 * 339 * Undefined if no bit exists, so code should check against 0 first. 340 */ 341 static inline unsigned long __ffs(unsigned long word) 342 { 343 return __flogr(-word & word) ^ (BITS_PER_LONG - 1); 344 } 345 346 /** 347 * ffs - find first bit set 348 * @word: the word to search 349 * 350 * This is defined the same way as the libc and 351 * compiler builtin ffs routines (man ffs). 352 */ 353 static inline int ffs(int word) 354 { 355 unsigned long mask = 2 * BITS_PER_LONG - 1; 356 unsigned int val = (unsigned int)word; 357 358 return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask; 359 } 360 361 /** 362 * __fls - find last (most-significant) set bit in a long word 363 * @word: the word to search 364 * 365 * Undefined if no set bit exists, so code should check against 0 first. 366 */ 367 static inline unsigned long __fls(unsigned long word) 368 { 369 return __flogr(word) ^ (BITS_PER_LONG - 1); 370 } 371 372 /** 373 * fls64 - find last set bit in a 64-bit word 374 * @word: the word to search 375 * 376 * This is defined in a similar way as the libc and compiler builtin 377 * ffsll, but returns the position of the most significant set bit. 378 * 379 * fls64(value) returns 0 if value is 0 or the position of the last 380 * set bit if value is nonzero. The last (most significant) bit is 381 * at position 64. 382 */ 383 static inline int fls64(unsigned long word) 384 { 385 unsigned long mask = 2 * BITS_PER_LONG - 1; 386 387 return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask; 388 } 389 390 /** 391 * fls - find last (most-significant) bit set 392 * @word: the word to search 393 * 394 * This is defined the same way as ffs. 395 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. 396 */ 397 static inline int fls(int word) 398 { 399 return fls64((unsigned int)word); 400 } 401 402 #else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */ 403 404 #include <asm-generic/bitops/__ffs.h> 405 #include <asm-generic/bitops/ffs.h> 406 #include <asm-generic/bitops/__fls.h> 407 #include <asm-generic/bitops/fls.h> 408 #include <asm-generic/bitops/fls64.h> 409 410 #endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */ 411 412 #include <asm-generic/bitops/ffz.h> 413 #include <asm-generic/bitops/find.h> 414 #include <asm-generic/bitops/hweight.h> 415 #include <asm-generic/bitops/sched.h> 416 #include <asm-generic/bitops/le.h> 417 #include <asm-generic/bitops/ext2-atomic-setbit.h> 418 419 #endif /* _S390_BITOPS_H */ 420