Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | #ifndef _X86_64_BITOPS_H |
| 2 | #define _X86_64_BITOPS_H |
| 3 | |
| 4 | /* |
| 5 | * Copyright 1992, Linus Torvalds. |
| 6 | */ |
| 7 | |
| 8 | #include <linux/config.h> |
| 9 | |
| 10 | #ifdef CONFIG_SMP |
| 11 | #define LOCK_PREFIX "lock ; " |
| 12 | #else |
| 13 | #define LOCK_PREFIX "" |
| 14 | #endif |
| 15 | |
| 16 | #define ADDR (*(volatile long *) addr) |
| 17 | |
| 18 | /** |
| 19 | * set_bit - Atomically set a bit in memory |
| 20 | * @nr: the bit to set |
| 21 | * @addr: the address to start counting from |
| 22 | * |
| 23 | * This function is atomic and may not be reordered. See __set_bit() |
| 24 | * if you do not require the atomic guarantees. |
| 25 | * Note that @nr may be almost arbitrarily large; this function is not |
| 26 | * restricted to acting on a single-word quantity. |
| 27 | */ |
| 28 | static __inline__ void set_bit(int nr, volatile void * addr) |
| 29 | { |
| 30 | __asm__ __volatile__( LOCK_PREFIX |
| 31 | "btsl %1,%0" |
| 32 | :"=m" (ADDR) |
| 33 | :"dIr" (nr) : "memory"); |
| 34 | } |
| 35 | |
| 36 | /** |
| 37 | * __set_bit - Set a bit in memory |
| 38 | * @nr: the bit to set |
| 39 | * @addr: the address to start counting from |
| 40 | * |
| 41 | * Unlike set_bit(), this function is non-atomic and may be reordered. |
| 42 | * If it's called on the same region of memory simultaneously, the effect |
| 43 | * may be that only one operation succeeds. |
| 44 | */ |
| 45 | static __inline__ void __set_bit(int nr, volatile void * addr) |
| 46 | { |
| 47 | __asm__ volatile( |
| 48 | "btsl %1,%0" |
| 49 | :"=m" (ADDR) |
| 50 | :"dIr" (nr) : "memory"); |
| 51 | } |
| 52 | |
| 53 | /** |
| 54 | * clear_bit - Clears a bit in memory |
| 55 | * @nr: Bit to clear |
| 56 | * @addr: Address to start counting from |
| 57 | * |
| 58 | * clear_bit() is atomic and may not be reordered. However, it does |
| 59 | * not contain a memory barrier, so if it is used for locking purposes, |
| 60 | * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit() |
| 61 | * in order to ensure changes are visible on other processors. |
| 62 | */ |
| 63 | static __inline__ void clear_bit(int nr, volatile void * addr) |
| 64 | { |
| 65 | __asm__ __volatile__( LOCK_PREFIX |
| 66 | "btrl %1,%0" |
| 67 | :"=m" (ADDR) |
| 68 | :"dIr" (nr)); |
| 69 | } |
| 70 | |
| 71 | static __inline__ void __clear_bit(int nr, volatile void * addr) |
| 72 | { |
| 73 | __asm__ __volatile__( |
| 74 | "btrl %1,%0" |
| 75 | :"=m" (ADDR) |
| 76 | :"dIr" (nr)); |
| 77 | } |
| 78 | |
| 79 | #define smp_mb__before_clear_bit() barrier() |
| 80 | #define smp_mb__after_clear_bit() barrier() |
| 81 | |
| 82 | /** |
| 83 | * __change_bit - Toggle a bit in memory |
| 84 | * @nr: the bit to change |
| 85 | * @addr: the address to start counting from |
| 86 | * |
| 87 | * Unlike change_bit(), this function is non-atomic and may be reordered. |
| 88 | * If it's called on the same region of memory simultaneously, the effect |
| 89 | * may be that only one operation succeeds. |
| 90 | */ |
| 91 | static __inline__ void __change_bit(int nr, volatile void * addr) |
| 92 | { |
| 93 | __asm__ __volatile__( |
| 94 | "btcl %1,%0" |
| 95 | :"=m" (ADDR) |
| 96 | :"dIr" (nr)); |
| 97 | } |
| 98 | |
| 99 | /** |
| 100 | * change_bit - Toggle a bit in memory |
| 101 | * @nr: Bit to change |
| 102 | * @addr: Address to start counting from |
| 103 | * |
| 104 | * change_bit() is atomic and may not be reordered. |
| 105 | * Note that @nr may be almost arbitrarily large; this function is not |
| 106 | * restricted to acting on a single-word quantity. |
| 107 | */ |
| 108 | static __inline__ void change_bit(int nr, volatile void * addr) |
| 109 | { |
| 110 | __asm__ __volatile__( LOCK_PREFIX |
| 111 | "btcl %1,%0" |
| 112 | :"=m" (ADDR) |
| 113 | :"dIr" (nr)); |
| 114 | } |
| 115 | |
| 116 | /** |
| 117 | * test_and_set_bit - Set a bit and return its old value |
| 118 | * @nr: Bit to set |
| 119 | * @addr: Address to count from |
| 120 | * |
| 121 | * This operation is atomic and cannot be reordered. |
| 122 | * It also implies a memory barrier. |
| 123 | */ |
| 124 | static __inline__ int test_and_set_bit(int nr, volatile void * addr) |
| 125 | { |
| 126 | int oldbit; |
| 127 | |
| 128 | __asm__ __volatile__( LOCK_PREFIX |
| 129 | "btsl %2,%1\n\tsbbl %0,%0" |
| 130 | :"=r" (oldbit),"=m" (ADDR) |
| 131 | :"dIr" (nr) : "memory"); |
| 132 | return oldbit; |
| 133 | } |
| 134 | |
| 135 | /** |
| 136 | * __test_and_set_bit - Set a bit and return its old value |
| 137 | * @nr: Bit to set |
| 138 | * @addr: Address to count from |
| 139 | * |
| 140 | * This operation is non-atomic and can be reordered. |
| 141 | * If two examples of this operation race, one can appear to succeed |
| 142 | * but actually fail. You must protect multiple accesses with a lock. |
| 143 | */ |
| 144 | static __inline__ int __test_and_set_bit(int nr, volatile void * addr) |
| 145 | { |
| 146 | int oldbit; |
| 147 | |
| 148 | __asm__( |
| 149 | "btsl %2,%1\n\tsbbl %0,%0" |
| 150 | :"=r" (oldbit),"=m" (ADDR) |
| 151 | :"dIr" (nr)); |
| 152 | return oldbit; |
| 153 | } |
| 154 | |
| 155 | /** |
| 156 | * test_and_clear_bit - Clear a bit and return its old value |
| 157 | * @nr: Bit to clear |
| 158 | * @addr: Address to count from |
| 159 | * |
| 160 | * This operation is atomic and cannot be reordered. |
| 161 | * It also implies a memory barrier. |
| 162 | */ |
| 163 | static __inline__ int test_and_clear_bit(int nr, volatile void * addr) |
| 164 | { |
| 165 | int oldbit; |
| 166 | |
| 167 | __asm__ __volatile__( LOCK_PREFIX |
| 168 | "btrl %2,%1\n\tsbbl %0,%0" |
| 169 | :"=r" (oldbit),"=m" (ADDR) |
| 170 | :"dIr" (nr) : "memory"); |
| 171 | return oldbit; |
| 172 | } |
| 173 | |
| 174 | /** |
| 175 | * __test_and_clear_bit - Clear a bit and return its old value |
| 176 | * @nr: Bit to clear |
| 177 | * @addr: Address to count from |
| 178 | * |
| 179 | * This operation is non-atomic and can be reordered. |
| 180 | * If two examples of this operation race, one can appear to succeed |
| 181 | * but actually fail. You must protect multiple accesses with a lock. |
| 182 | */ |
| 183 | static __inline__ int __test_and_clear_bit(int nr, volatile void * addr) |
| 184 | { |
| 185 | int oldbit; |
| 186 | |
| 187 | __asm__( |
| 188 | "btrl %2,%1\n\tsbbl %0,%0" |
| 189 | :"=r" (oldbit),"=m" (ADDR) |
| 190 | :"dIr" (nr)); |
| 191 | return oldbit; |
| 192 | } |
| 193 | |
| 194 | /* WARNING: non atomic and it can be reordered! */ |
| 195 | static __inline__ int __test_and_change_bit(int nr, volatile void * addr) |
| 196 | { |
| 197 | int oldbit; |
| 198 | |
| 199 | __asm__ __volatile__( |
| 200 | "btcl %2,%1\n\tsbbl %0,%0" |
| 201 | :"=r" (oldbit),"=m" (ADDR) |
| 202 | :"dIr" (nr) : "memory"); |
| 203 | return oldbit; |
| 204 | } |
| 205 | |
| 206 | /** |
| 207 | * test_and_change_bit - Change a bit and return its old value |
| 208 | * @nr: Bit to change |
| 209 | * @addr: Address to count from |
| 210 | * |
| 211 | * This operation is atomic and cannot be reordered. |
| 212 | * It also implies a memory barrier. |
| 213 | */ |
| 214 | static __inline__ int test_and_change_bit(int nr, volatile void * addr) |
| 215 | { |
| 216 | int oldbit; |
| 217 | |
| 218 | __asm__ __volatile__( LOCK_PREFIX |
| 219 | "btcl %2,%1\n\tsbbl %0,%0" |
| 220 | :"=r" (oldbit),"=m" (ADDR) |
| 221 | :"dIr" (nr) : "memory"); |
| 222 | return oldbit; |
| 223 | } |
| 224 | |
| 225 | #if 0 /* Fool kernel-doc since it doesn't do macros yet */ |
| 226 | /** |
| 227 | * test_bit - Determine whether a bit is set |
| 228 | * @nr: bit number to test |
| 229 | * @addr: Address to start counting from |
| 230 | */ |
| 231 | static int test_bit(int nr, const volatile void * addr); |
| 232 | #endif |
| 233 | |
| 234 | static __inline__ int constant_test_bit(int nr, const volatile void * addr) |
| 235 | { |
| 236 | return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0; |
| 237 | } |
| 238 | |
| 239 | static __inline__ int variable_test_bit(int nr, volatile const void * addr) |
| 240 | { |
| 241 | int oldbit; |
| 242 | |
| 243 | __asm__ __volatile__( |
| 244 | "btl %2,%1\n\tsbbl %0,%0" |
| 245 | :"=r" (oldbit) |
| 246 | :"m" (ADDR),"dIr" (nr)); |
| 247 | return oldbit; |
| 248 | } |
| 249 | |
| 250 | #define test_bit(nr,addr) \ |
| 251 | (__builtin_constant_p(nr) ? \ |
| 252 | constant_test_bit((nr),(addr)) : \ |
| 253 | variable_test_bit((nr),(addr))) |
| 254 | |
| 255 | #undef ADDR |
| 256 | |
| 257 | extern long find_first_zero_bit(const unsigned long * addr, unsigned long size); |
| 258 | extern long find_next_zero_bit (const unsigned long * addr, long size, long offset); |
| 259 | extern long find_first_bit(const unsigned long * addr, unsigned long size); |
| 260 | extern long find_next_bit(const unsigned long * addr, long size, long offset); |
| 261 | |
| 262 | /* return index of first bet set in val or max when no bit is set */ |
| 263 | static inline unsigned long __scanbit(unsigned long val, unsigned long max) |
| 264 | { |
| 265 | asm("bsfq %1,%0 ; cmovz %2,%0" : "=&r" (val) : "r" (val), "r" (max)); |
| 266 | return val; |
| 267 | } |
| 268 | |
| 269 | #define find_first_bit(addr,size) \ |
| 270 | ((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \ |
| 271 | (__scanbit(*(unsigned long *)addr,(size))) : \ |
| 272 | find_first_bit(addr,size))) |
| 273 | |
| 274 | #define find_next_bit(addr,size,off) \ |
| 275 | ((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \ |
| 276 | ((off) + (__scanbit((*(unsigned long *)addr) >> (off),(size)-(off)))) : \ |
| 277 | find_next_bit(addr,size,off))) |
| 278 | |
| 279 | #define find_first_zero_bit(addr,size) \ |
| 280 | ((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \ |
| 281 | (__scanbit(~*(unsigned long *)addr,(size))) : \ |
| 282 | find_first_zero_bit(addr,size))) |
| 283 | |
| 284 | #define find_next_zero_bit(addr,size,off) \ |
| 285 | ((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \ |
| 286 | ((off)+(__scanbit(~(((*(unsigned long *)addr)) >> (off)),(size)-(off)))) : \ |
| 287 | find_next_zero_bit(addr,size,off))) |
| 288 | |
| 289 | /* |
| 290 | * Find string of zero bits in a bitmap. -1 when not found. |
| 291 | */ |
| 292 | extern unsigned long |
| 293 | find_next_zero_string(unsigned long *bitmap, long start, long nbits, int len); |
| 294 | |
| 295 | static inline void set_bit_string(unsigned long *bitmap, unsigned long i, |
| 296 | int len) |
| 297 | { |
| 298 | unsigned long end = i + len; |
| 299 | while (i < end) { |
| 300 | __set_bit(i, bitmap); |
| 301 | i++; |
| 302 | } |
| 303 | } |
| 304 | |
| 305 | static inline void __clear_bit_string(unsigned long *bitmap, unsigned long i, |
| 306 | int len) |
| 307 | { |
| 308 | unsigned long end = i + len; |
| 309 | while (i < end) { |
| 310 | __clear_bit(i, bitmap); |
| 311 | i++; |
| 312 | } |
| 313 | } |
| 314 | |
| 315 | /** |
| 316 | * ffz - find first zero in word. |
| 317 | * @word: The word to search |
| 318 | * |
| 319 | * Undefined if no zero exists, so code should check against ~0UL first. |
| 320 | */ |
| 321 | static __inline__ unsigned long ffz(unsigned long word) |
| 322 | { |
| 323 | __asm__("bsfq %1,%0" |
| 324 | :"=r" (word) |
| 325 | :"r" (~word)); |
| 326 | return word; |
| 327 | } |
| 328 | |
| 329 | /** |
| 330 | * __ffs - find first bit in word. |
| 331 | * @word: The word to search |
| 332 | * |
| 333 | * Undefined if no bit exists, so code should check against 0 first. |
| 334 | */ |
| 335 | static __inline__ unsigned long __ffs(unsigned long word) |
| 336 | { |
| 337 | __asm__("bsfq %1,%0" |
| 338 | :"=r" (word) |
| 339 | :"rm" (word)); |
| 340 | return word; |
| 341 | } |
| 342 | |
| 343 | #ifdef __KERNEL__ |
| 344 | |
| 345 | static inline int sched_find_first_bit(const unsigned long *b) |
| 346 | { |
| 347 | if (b[0]) |
| 348 | return __ffs(b[0]); |
| 349 | if (b[1]) |
| 350 | return __ffs(b[1]) + 64; |
Jesse Millan | 8d224d3 | 2005-07-28 21:15:51 -0700 | [diff] [blame] | 351 | return __ffs(b[2]) + 128; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | } |
| 353 | |
| 354 | /** |
| 355 | * ffs - find first bit set |
| 356 | * @x: the word to search |
| 357 | * |
| 358 | * This is defined the same way as |
| 359 | * the libc and compiler builtin ffs routines, therefore |
| 360 | * differs in spirit from the above ffz (man ffs). |
| 361 | */ |
| 362 | static __inline__ int ffs(int x) |
| 363 | { |
| 364 | int r; |
| 365 | |
| 366 | __asm__("bsfl %1,%0\n\t" |
| 367 | "cmovzl %2,%0" |
| 368 | : "=r" (r) : "rm" (x), "r" (-1)); |
| 369 | return r+1; |
| 370 | } |
| 371 | |
| 372 | /** |
| 373 | * hweightN - returns the hamming weight of a N-bit word |
| 374 | * @x: the word to weigh |
| 375 | * |
| 376 | * The Hamming Weight of a number is the total number of bits set in it. |
| 377 | */ |
| 378 | |
| 379 | #define hweight64(x) generic_hweight64(x) |
| 380 | #define hweight32(x) generic_hweight32(x) |
| 381 | #define hweight16(x) generic_hweight16(x) |
| 382 | #define hweight8(x) generic_hweight8(x) |
| 383 | |
| 384 | #endif /* __KERNEL__ */ |
| 385 | |
| 386 | #ifdef __KERNEL__ |
| 387 | |
| 388 | #define ext2_set_bit(nr,addr) \ |
| 389 | __test_and_set_bit((nr),(unsigned long*)addr) |
| 390 | #define ext2_set_bit_atomic(lock,nr,addr) \ |
| 391 | test_and_set_bit((nr),(unsigned long*)addr) |
| 392 | #define ext2_clear_bit(nr, addr) \ |
| 393 | __test_and_clear_bit((nr),(unsigned long*)addr) |
| 394 | #define ext2_clear_bit_atomic(lock,nr,addr) \ |
| 395 | test_and_clear_bit((nr),(unsigned long*)addr) |
| 396 | #define ext2_test_bit(nr, addr) test_bit((nr),(unsigned long*)addr) |
| 397 | #define ext2_find_first_zero_bit(addr, size) \ |
| 398 | find_first_zero_bit((unsigned long*)addr, size) |
| 399 | #define ext2_find_next_zero_bit(addr, size, off) \ |
| 400 | find_next_zero_bit((unsigned long*)addr, size, off) |
| 401 | |
| 402 | /* Bitmap functions for the minix filesystem. */ |
| 403 | #define minix_test_and_set_bit(nr,addr) __test_and_set_bit(nr,(void*)addr) |
| 404 | #define minix_set_bit(nr,addr) __set_bit(nr,(void*)addr) |
| 405 | #define minix_test_and_clear_bit(nr,addr) __test_and_clear_bit(nr,(void*)addr) |
| 406 | #define minix_test_bit(nr,addr) test_bit(nr,(void*)addr) |
| 407 | #define minix_find_first_zero_bit(addr,size) \ |
| 408 | find_first_zero_bit((void*)addr,size) |
| 409 | |
| 410 | /* find last set bit */ |
| 411 | #define fls(x) generic_fls(x) |
| 412 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 413 | #endif /* __KERNEL__ */ |
| 414 | |
| 415 | #endif /* _X86_64_BITOPS_H */ |