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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 | #ifndef _ASM_IA64_BITOPS_H #define _ASM_IA64_BITOPS_H /* * Copyright (C) 1998-2001 Hewlett-Packard Co * Copyright (C) 1998-2001 David Mosberger-Tang <davidm@hpl.hp.com> */ #include <asm/system.h> /** * set_bit - Atomically set a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * This function is atomic and may not be reordered. See __set_bit() * if you do not require the atomic guarantees. * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. * * The address must be (at least) "long" aligned. * Note that there are driver (e.g., eepro100) which use these operations to operate on * hw-defined data-structures, so we can't easily change these operations to force a * bigger alignment. * * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). */ static __inline__ void set_bit (int nr, volatile void *addr) { __u32 bit, old, new; volatile __u32 *m; CMPXCHG_BUGCHECK_DECL m = (volatile __u32 *) addr + (nr >> 5); bit = 1 << (nr & 31); do { CMPXCHG_BUGCHECK(m); old = *m; new = old | bit; } while (cmpxchg_acq(m, old, new) != old); } /** * __set_bit - Set a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * Unlike set_bit(), this function is non-atomic and may be reordered. * If it's called on the same region of memory simultaneously, the effect * may be that only one operation succeeds. */ static __inline__ void __set_bit (int nr, volatile void *addr) { *((__u32 *) addr + (nr >> 5)) |= (1 << (nr & 31)); } /* * clear_bit() doesn't provide any barrier for the compiler. */ #define smp_mb__before_clear_bit() smp_mb() #define smp_mb__after_clear_bit() smp_mb() /** * clear_bit - Clears a bit in memory * @nr: Bit to clear * @addr: Address to start counting from * * clear_bit() is atomic and may not be reordered. However, it does * not contain a memory barrier, so if it is used for locking purposes, * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit() * in order to ensure changes are visible on other processors. */ static __inline__ void clear_bit (int nr, volatile void *addr) { __u32 mask, old, new; volatile __u32 *m; CMPXCHG_BUGCHECK_DECL m = (volatile __u32 *) addr + (nr >> 5); mask = ~(1 << (nr & 31)); do { CMPXCHG_BUGCHECK(m); old = *m; new = old & mask; } while (cmpxchg_acq(m, old, new) != old); } /** * change_bit - Toggle a bit in memory * @nr: Bit to clear * @addr: Address to start counting from * * change_bit() is atomic and may not be reordered. * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. */ static __inline__ void change_bit (int nr, volatile void *addr) { __u32 bit, old, new; volatile __u32 *m; CMPXCHG_BUGCHECK_DECL m = (volatile __u32 *) addr + (nr >> 5); bit = (1 << (nr & 31)); do { CMPXCHG_BUGCHECK(m); old = *m; new = old ^ bit; } while (cmpxchg_acq(m, old, new) != old); } /** * __change_bit - Toggle a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * Unlike change_bit(), this function is non-atomic and may be reordered. * If it's called on the same region of memory simultaneously, the effect * may be that only one operation succeeds. */ static __inline__ void __change_bit (int nr, volatile void *addr) { *((__u32 *) addr + (nr >> 5)) ^= (1 << (nr & 31)); } /** * test_and_set_bit - Set a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ static __inline__ int test_and_set_bit (int nr, volatile void *addr) { __u32 bit, old, new; volatile __u32 *m; CMPXCHG_BUGCHECK_DECL m = (volatile __u32 *) addr + (nr >> 5); bit = 1 << (nr & 31); do { CMPXCHG_BUGCHECK(m); old = *m; new = old | bit; } while (cmpxchg_acq(m, old, new) != old); return (old & bit) != 0; } /** * __test_and_set_bit - Set a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */ static __inline__ int __test_and_set_bit (int nr, volatile void *addr) { __u32 *p = (__u32 *) addr + (nr >> 5); __u32 m = 1 << (nr & 31); int oldbitset = (*p & m) != 0; *p |= m; return oldbitset; } /** * test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ static __inline__ int test_and_clear_bit (int nr, volatile void *addr) { __u32 mask, old, new; volatile __u32 *m; CMPXCHG_BUGCHECK_DECL m = (volatile __u32 *) addr + (nr >> 5); mask = ~(1 << (nr & 31)); do { CMPXCHG_BUGCHECK(m); old = *m; new = old & mask; } while (cmpxchg_acq(m, old, new) != old); return (old & ~mask) != 0; } /** * __test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */ static __inline__ int __test_and_clear_bit(int nr, volatile void * addr) { __u32 *p = (__u32 *) addr + (nr >> 5); __u32 m = 1 << (nr & 31); int oldbitset = *p & m; *p &= ~m; return oldbitset; } /** * test_and_change_bit - Change a bit and return its new value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ static __inline__ int test_and_change_bit (int nr, volatile void *addr) { __u32 bit, old, new; volatile __u32 *m; CMPXCHG_BUGCHECK_DECL m = (volatile __u32 *) addr + (nr >> 5); bit = (1 << (nr & 31)); do { CMPXCHG_BUGCHECK(m); old = *m; new = old ^ bit; } while (cmpxchg_acq(m, old, new) != old); return (old & bit) != 0; } /* * WARNING: non atomic version. */ static __inline__ int __test_and_change_bit (int nr, void *addr) { __u32 old, bit = (1 << (nr & 31)); __u32 *m = (__u32 *) addr + (nr >> 5); old = *m; *m = old ^ bit; return (old & bit) != 0; } static __inline__ int test_bit (int nr, volatile void *addr) { return 1 & (((const volatile __u32 *) addr)[nr >> 5] >> (nr & 31)); } /** * ffz - find the first zero bit in a memory region * @x: The address to start the search at * * Returns the bit-number (0..63) of the first (least significant) zero bit, not * the number of the byte containing a bit. Undefined if no zero exists, so * code should check against ~0UL first... */ static inline unsigned long ffz (unsigned long x) { unsigned long result; __asm__ ("popcnt %0=%1" : "=r" (result) : "r" (x & (~x - 1))); return result; } #ifdef __KERNEL__ /* * find_last_zero_bit - find the last zero bit in a 64 bit quantity * @x: The value to search */ static inline unsigned long ia64_fls (unsigned long x) { double d = x; long exp; __asm__ ("getf.exp %0=%1" : "=r"(exp) : "f"(d)); return exp - 0xffff; } /* * ffs: find first bit set. This is defined the same way as the libc and compiler builtin * ffs routines, therefore differs in spirit from the above ffz (man ffs): it operates on * "int" values only and the result value is the bit number + 1. ffs(0) is defined to * return zero. */ #define ffs(x) __builtin_ffs(x) /* * hweightN: returns the hamming weight (i.e. the number * of bits set) of a N-bit word */ static __inline__ unsigned long hweight64 (unsigned long x) { unsigned long result; __asm__ ("popcnt %0=%1" : "=r" (result) : "r" (x)); return result; } #define hweight32(x) hweight64 ((x) & 0xfffffffful) #define hweight16(x) hweight64 ((x) & 0xfffful) #define hweight8(x) hweight64 ((x) & 0xfful) #endif /* __KERNEL__ */ /* * Find next zero bit in a bitmap reasonably efficiently.. */ static inline int find_next_zero_bit (void *addr, unsigned long size, unsigned long offset) { unsigned long *p = ((unsigned long *) addr) + (offset >> 6); unsigned long result = offset & ~63UL; unsigned long tmp; if (offset >= size) return size; size -= result; offset &= 63UL; if (offset) { tmp = *(p++); tmp |= ~0UL >> (64-offset); if (size < 64) goto found_first; if (~tmp) goto found_middle; size -= 64; result += 64; } while (size & ~63UL) { if (~(tmp = *(p++))) goto found_middle; result += 64; size -= 64; } if (!size) return result; tmp = *p; found_first: tmp |= ~0UL << size; found_middle: return result + ffz(tmp); } /* * The optimizer actually does good code for this case.. */ #define find_first_zero_bit(addr, size) find_next_zero_bit((addr), (size), 0) #ifdef __KERNEL__ #define ext2_set_bit test_and_set_bit #define ext2_clear_bit test_and_clear_bit #define ext2_test_bit test_bit #define ext2_find_first_zero_bit find_first_zero_bit #define ext2_find_next_zero_bit find_next_zero_bit /* Bitmap functions for the minix filesystem. */ #define minix_test_and_set_bit(nr,addr) test_and_set_bit(nr,addr) #define minix_set_bit(nr,addr) set_bit(nr,addr) #define minix_test_and_clear_bit(nr,addr) test_and_clear_bit(nr,addr) #define minix_test_bit(nr,addr) test_bit(nr,addr) #define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size) #endif /* __KERNEL__ */ #endif /* _ASM_IA64_BITOPS_H */ |