bitmap.h (22105B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef __LINUX_BITMAP_H 3#define __LINUX_BITMAP_H 4 5#ifndef __ASSEMBLY__ 6 7#include <linux/align.h> 8#include <linux/bitops.h> 9#include <linux/find.h> 10#include <linux/limits.h> 11#include <linux/string.h> 12#include <linux/types.h> 13 14struct device; 15 16/* 17 * bitmaps provide bit arrays that consume one or more unsigned 18 * longs. The bitmap interface and available operations are listed 19 * here, in bitmap.h 20 * 21 * Function implementations generic to all architectures are in 22 * lib/bitmap.c. Functions implementations that are architecture 23 * specific are in various include/asm-<arch>/bitops.h headers 24 * and other arch/<arch> specific files. 25 * 26 * See lib/bitmap.c for more details. 27 */ 28 29/** 30 * DOC: bitmap overview 31 * 32 * The available bitmap operations and their rough meaning in the 33 * case that the bitmap is a single unsigned long are thus: 34 * 35 * The generated code is more efficient when nbits is known at 36 * compile-time and at most BITS_PER_LONG. 37 * 38 * :: 39 * 40 * bitmap_zero(dst, nbits) *dst = 0UL 41 * bitmap_fill(dst, nbits) *dst = ~0UL 42 * bitmap_copy(dst, src, nbits) *dst = *src 43 * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2 44 * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2 45 * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2 46 * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2) 47 * bitmap_complement(dst, src, nbits) *dst = ~(*src) 48 * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal? 49 * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap? 50 * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2? 51 * bitmap_empty(src, nbits) Are all bits zero in *src? 52 * bitmap_full(src, nbits) Are all bits set in *src? 53 * bitmap_weight(src, nbits) Hamming Weight: number set bits 54 * bitmap_set(dst, pos, nbits) Set specified bit area 55 * bitmap_clear(dst, pos, nbits) Clear specified bit area 56 * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area 57 * bitmap_find_next_zero_area_off(buf, len, pos, n, mask, mask_off) as above 58 * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n 59 * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n 60 * bitmap_cut(dst, src, first, n, nbits) Cut n bits from first, copy rest 61 * bitmap_replace(dst, old, new, mask, nbits) *dst = (*old & ~(*mask)) | (*new & *mask) 62 * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src) 63 * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit) 64 * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap 65 * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz 66 * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf 67 * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf 68 * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf 69 * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf 70 * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region 71 * bitmap_release_region(bitmap, pos, order) Free specified bit region 72 * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region 73 * bitmap_from_arr32(dst, buf, nbits) Copy nbits from u32[] buf to dst 74 * bitmap_to_arr32(buf, src, nbits) Copy nbits from buf to u32[] dst 75 * bitmap_to_arr64(buf, src, nbits) Copy nbits from buf to u64[] dst 76 * bitmap_to_arr64(buf, src, nbits) Copy nbits from buf to u64[] dst 77 * bitmap_get_value8(map, start) Get 8bit value from map at start 78 * bitmap_set_value8(map, value, start) Set 8bit value to map at start 79 * 80 * Note, bitmap_zero() and bitmap_fill() operate over the region of 81 * unsigned longs, that is, bits behind bitmap till the unsigned long 82 * boundary will be zeroed or filled as well. Consider to use 83 * bitmap_clear() or bitmap_set() to make explicit zeroing or filling 84 * respectively. 85 */ 86 87/** 88 * DOC: bitmap bitops 89 * 90 * Also the following operations in asm/bitops.h apply to bitmaps.:: 91 * 92 * set_bit(bit, addr) *addr |= bit 93 * clear_bit(bit, addr) *addr &= ~bit 94 * change_bit(bit, addr) *addr ^= bit 95 * test_bit(bit, addr) Is bit set in *addr? 96 * test_and_set_bit(bit, addr) Set bit and return old value 97 * test_and_clear_bit(bit, addr) Clear bit and return old value 98 * test_and_change_bit(bit, addr) Change bit and return old value 99 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr 100 * find_first_bit(addr, nbits) Position first set bit in *addr 101 * find_next_zero_bit(addr, nbits, bit) 102 * Position next zero bit in *addr >= bit 103 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit 104 * find_next_and_bit(addr1, addr2, nbits, bit) 105 * Same as find_next_bit, but in 106 * (*addr1 & *addr2) 107 * 108 */ 109 110/** 111 * DOC: declare bitmap 112 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used 113 * to declare an array named 'name' of just enough unsigned longs to 114 * contain all bit positions from 0 to 'bits' - 1. 115 */ 116 117/* 118 * Allocation and deallocation of bitmap. 119 * Provided in lib/bitmap.c to avoid circular dependency. 120 */ 121unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags); 122unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags); 123unsigned long *bitmap_alloc_node(unsigned int nbits, gfp_t flags, int node); 124unsigned long *bitmap_zalloc_node(unsigned int nbits, gfp_t flags, int node); 125void bitmap_free(const unsigned long *bitmap); 126 127/* Managed variants of the above. */ 128unsigned long *devm_bitmap_alloc(struct device *dev, 129 unsigned int nbits, gfp_t flags); 130unsigned long *devm_bitmap_zalloc(struct device *dev, 131 unsigned int nbits, gfp_t flags); 132 133/* 134 * lib/bitmap.c provides these functions: 135 */ 136 137bool __bitmap_equal(const unsigned long *bitmap1, 138 const unsigned long *bitmap2, unsigned int nbits); 139bool __pure __bitmap_or_equal(const unsigned long *src1, 140 const unsigned long *src2, 141 const unsigned long *src3, 142 unsigned int nbits); 143void __bitmap_complement(unsigned long *dst, const unsigned long *src, 144 unsigned int nbits); 145void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, 146 unsigned int shift, unsigned int nbits); 147void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, 148 unsigned int shift, unsigned int nbits); 149void bitmap_cut(unsigned long *dst, const unsigned long *src, 150 unsigned int first, unsigned int cut, unsigned int nbits); 151int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, 152 const unsigned long *bitmap2, unsigned int nbits); 153void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, 154 const unsigned long *bitmap2, unsigned int nbits); 155void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, 156 const unsigned long *bitmap2, unsigned int nbits); 157int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, 158 const unsigned long *bitmap2, unsigned int nbits); 159void __bitmap_replace(unsigned long *dst, 160 const unsigned long *old, const unsigned long *new, 161 const unsigned long *mask, unsigned int nbits); 162bool __bitmap_intersects(const unsigned long *bitmap1, 163 const unsigned long *bitmap2, unsigned int nbits); 164bool __bitmap_subset(const unsigned long *bitmap1, 165 const unsigned long *bitmap2, unsigned int nbits); 166int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits); 167void __bitmap_set(unsigned long *map, unsigned int start, int len); 168void __bitmap_clear(unsigned long *map, unsigned int start, int len); 169 170unsigned long bitmap_find_next_zero_area_off(unsigned long *map, 171 unsigned long size, 172 unsigned long start, 173 unsigned int nr, 174 unsigned long align_mask, 175 unsigned long align_offset); 176 177/** 178 * bitmap_find_next_zero_area - find a contiguous aligned zero area 179 * @map: The address to base the search on 180 * @size: The bitmap size in bits 181 * @start: The bitnumber to start searching at 182 * @nr: The number of zeroed bits we're looking for 183 * @align_mask: Alignment mask for zero area 184 * 185 * The @align_mask should be one less than a power of 2; the effect is that 186 * the bit offset of all zero areas this function finds is multiples of that 187 * power of 2. A @align_mask of 0 means no alignment is required. 188 */ 189static inline unsigned long 190bitmap_find_next_zero_area(unsigned long *map, 191 unsigned long size, 192 unsigned long start, 193 unsigned int nr, 194 unsigned long align_mask) 195{ 196 return bitmap_find_next_zero_area_off(map, size, start, nr, 197 align_mask, 0); 198} 199 200int bitmap_parse(const char *buf, unsigned int buflen, 201 unsigned long *dst, int nbits); 202int bitmap_parse_user(const char __user *ubuf, unsigned int ulen, 203 unsigned long *dst, int nbits); 204int bitmap_parselist(const char *buf, unsigned long *maskp, 205 int nmaskbits); 206int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen, 207 unsigned long *dst, int nbits); 208void bitmap_remap(unsigned long *dst, const unsigned long *src, 209 const unsigned long *old, const unsigned long *new, unsigned int nbits); 210int bitmap_bitremap(int oldbit, 211 const unsigned long *old, const unsigned long *new, int bits); 212void bitmap_onto(unsigned long *dst, const unsigned long *orig, 213 const unsigned long *relmap, unsigned int bits); 214void bitmap_fold(unsigned long *dst, const unsigned long *orig, 215 unsigned int sz, unsigned int nbits); 216int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order); 217void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order); 218int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order); 219 220#ifdef __BIG_ENDIAN 221void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits); 222#else 223#define bitmap_copy_le bitmap_copy 224#endif 225unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits); 226int bitmap_print_to_pagebuf(bool list, char *buf, 227 const unsigned long *maskp, int nmaskbits); 228 229extern int bitmap_print_bitmask_to_buf(char *buf, const unsigned long *maskp, 230 int nmaskbits, loff_t off, size_t count); 231 232extern int bitmap_print_list_to_buf(char *buf, const unsigned long *maskp, 233 int nmaskbits, loff_t off, size_t count); 234 235#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1))) 236#define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1))) 237 238static inline void bitmap_zero(unsigned long *dst, unsigned int nbits) 239{ 240 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); 241 memset(dst, 0, len); 242} 243 244static inline void bitmap_fill(unsigned long *dst, unsigned int nbits) 245{ 246 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); 247 memset(dst, 0xff, len); 248} 249 250static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, 251 unsigned int nbits) 252{ 253 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); 254 memcpy(dst, src, len); 255} 256 257/* 258 * Copy bitmap and clear tail bits in last word. 259 */ 260static inline void bitmap_copy_clear_tail(unsigned long *dst, 261 const unsigned long *src, unsigned int nbits) 262{ 263 bitmap_copy(dst, src, nbits); 264 if (nbits % BITS_PER_LONG) 265 dst[nbits / BITS_PER_LONG] &= BITMAP_LAST_WORD_MASK(nbits); 266} 267 268/* 269 * On 32-bit systems bitmaps are represented as u32 arrays internally. On LE64 270 * machines the order of hi and lo parts of numbers match the bitmap structure. 271 * In both cases conversion is not needed when copying data from/to arrays of 272 * u32. But in LE64 case, typecast in bitmap_copy_clear_tail() may lead 273 * to out-of-bound access. To avoid that, both LE and BE variants of 64-bit 274 * architectures are not using bitmap_copy_clear_tail(). 275 */ 276#if BITS_PER_LONG == 64 277void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, 278 unsigned int nbits); 279void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, 280 unsigned int nbits); 281#else 282#define bitmap_from_arr32(bitmap, buf, nbits) \ 283 bitmap_copy_clear_tail((unsigned long *) (bitmap), \ 284 (const unsigned long *) (buf), (nbits)) 285#define bitmap_to_arr32(buf, bitmap, nbits) \ 286 bitmap_copy_clear_tail((unsigned long *) (buf), \ 287 (const unsigned long *) (bitmap), (nbits)) 288#endif 289 290/* 291 * On 64-bit systems bitmaps are represented as u64 arrays internally. On LE32 292 * machines the order of hi and lo parts of numbers match the bitmap structure. 293 * In both cases conversion is not needed when copying data from/to arrays of 294 * u64. 295 */ 296#if (BITS_PER_LONG == 32) && defined(__BIG_ENDIAN) 297void bitmap_from_arr64(unsigned long *bitmap, const u64 *buf, unsigned int nbits); 298void bitmap_to_arr64(u64 *buf, const unsigned long *bitmap, unsigned int nbits); 299#else 300#define bitmap_from_arr64(bitmap, buf, nbits) \ 301 bitmap_copy_clear_tail((unsigned long *)(bitmap), (const unsigned long *)(buf), (nbits)) 302#define bitmap_to_arr64(buf, bitmap, nbits) \ 303 bitmap_copy_clear_tail((unsigned long *)(buf), (const unsigned long *)(bitmap), (nbits)) 304#endif 305 306static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, 307 const unsigned long *src2, unsigned int nbits) 308{ 309 if (small_const_nbits(nbits)) 310 return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0; 311 return __bitmap_and(dst, src1, src2, nbits); 312} 313 314static inline void bitmap_or(unsigned long *dst, const unsigned long *src1, 315 const unsigned long *src2, unsigned int nbits) 316{ 317 if (small_const_nbits(nbits)) 318 *dst = *src1 | *src2; 319 else 320 __bitmap_or(dst, src1, src2, nbits); 321} 322 323static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, 324 const unsigned long *src2, unsigned int nbits) 325{ 326 if (small_const_nbits(nbits)) 327 *dst = *src1 ^ *src2; 328 else 329 __bitmap_xor(dst, src1, src2, nbits); 330} 331 332static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1, 333 const unsigned long *src2, unsigned int nbits) 334{ 335 if (small_const_nbits(nbits)) 336 return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; 337 return __bitmap_andnot(dst, src1, src2, nbits); 338} 339 340static inline void bitmap_complement(unsigned long *dst, const unsigned long *src, 341 unsigned int nbits) 342{ 343 if (small_const_nbits(nbits)) 344 *dst = ~(*src); 345 else 346 __bitmap_complement(dst, src, nbits); 347} 348 349#ifdef __LITTLE_ENDIAN 350#define BITMAP_MEM_ALIGNMENT 8 351#else 352#define BITMAP_MEM_ALIGNMENT (8 * sizeof(unsigned long)) 353#endif 354#define BITMAP_MEM_MASK (BITMAP_MEM_ALIGNMENT - 1) 355 356static inline bool bitmap_equal(const unsigned long *src1, 357 const unsigned long *src2, unsigned int nbits) 358{ 359 if (small_const_nbits(nbits)) 360 return !((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); 361 if (__builtin_constant_p(nbits & BITMAP_MEM_MASK) && 362 IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) 363 return !memcmp(src1, src2, nbits / 8); 364 return __bitmap_equal(src1, src2, nbits); 365} 366 367/** 368 * bitmap_or_equal - Check whether the or of two bitmaps is equal to a third 369 * @src1: Pointer to bitmap 1 370 * @src2: Pointer to bitmap 2 will be or'ed with bitmap 1 371 * @src3: Pointer to bitmap 3. Compare to the result of *@src1 | *@src2 372 * @nbits: number of bits in each of these bitmaps 373 * 374 * Returns: True if (*@src1 | *@src2) == *@src3, false otherwise 375 */ 376static inline bool bitmap_or_equal(const unsigned long *src1, 377 const unsigned long *src2, 378 const unsigned long *src3, 379 unsigned int nbits) 380{ 381 if (!small_const_nbits(nbits)) 382 return __bitmap_or_equal(src1, src2, src3, nbits); 383 384 return !(((*src1 | *src2) ^ *src3) & BITMAP_LAST_WORD_MASK(nbits)); 385} 386 387static inline bool bitmap_intersects(const unsigned long *src1, 388 const unsigned long *src2, 389 unsigned int nbits) 390{ 391 if (small_const_nbits(nbits)) 392 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; 393 else 394 return __bitmap_intersects(src1, src2, nbits); 395} 396 397static inline bool bitmap_subset(const unsigned long *src1, 398 const unsigned long *src2, unsigned int nbits) 399{ 400 if (small_const_nbits(nbits)) 401 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits)); 402 else 403 return __bitmap_subset(src1, src2, nbits); 404} 405 406static inline bool bitmap_empty(const unsigned long *src, unsigned nbits) 407{ 408 if (small_const_nbits(nbits)) 409 return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); 410 411 return find_first_bit(src, nbits) == nbits; 412} 413 414static inline bool bitmap_full(const unsigned long *src, unsigned int nbits) 415{ 416 if (small_const_nbits(nbits)) 417 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits)); 418 419 return find_first_zero_bit(src, nbits) == nbits; 420} 421 422static __always_inline int bitmap_weight(const unsigned long *src, unsigned int nbits) 423{ 424 if (small_const_nbits(nbits)) 425 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits)); 426 return __bitmap_weight(src, nbits); 427} 428 429static __always_inline void bitmap_set(unsigned long *map, unsigned int start, 430 unsigned int nbits) 431{ 432 if (__builtin_constant_p(nbits) && nbits == 1) 433 __set_bit(start, map); 434 else if (__builtin_constant_p(start & BITMAP_MEM_MASK) && 435 IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) && 436 __builtin_constant_p(nbits & BITMAP_MEM_MASK) && 437 IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) 438 memset((char *)map + start / 8, 0xff, nbits / 8); 439 else 440 __bitmap_set(map, start, nbits); 441} 442 443static __always_inline void bitmap_clear(unsigned long *map, unsigned int start, 444 unsigned int nbits) 445{ 446 if (__builtin_constant_p(nbits) && nbits == 1) 447 __clear_bit(start, map); 448 else if (__builtin_constant_p(start & BITMAP_MEM_MASK) && 449 IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) && 450 __builtin_constant_p(nbits & BITMAP_MEM_MASK) && 451 IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) 452 memset((char *)map + start / 8, 0, nbits / 8); 453 else 454 __bitmap_clear(map, start, nbits); 455} 456 457static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src, 458 unsigned int shift, unsigned int nbits) 459{ 460 if (small_const_nbits(nbits)) 461 *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift; 462 else 463 __bitmap_shift_right(dst, src, shift, nbits); 464} 465 466static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src, 467 unsigned int shift, unsigned int nbits) 468{ 469 if (small_const_nbits(nbits)) 470 *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits); 471 else 472 __bitmap_shift_left(dst, src, shift, nbits); 473} 474 475static inline void bitmap_replace(unsigned long *dst, 476 const unsigned long *old, 477 const unsigned long *new, 478 const unsigned long *mask, 479 unsigned int nbits) 480{ 481 if (small_const_nbits(nbits)) 482 *dst = (*old & ~(*mask)) | (*new & *mask); 483 else 484 __bitmap_replace(dst, old, new, mask, nbits); 485} 486 487static inline void bitmap_next_set_region(unsigned long *bitmap, 488 unsigned int *rs, unsigned int *re, 489 unsigned int end) 490{ 491 *rs = find_next_bit(bitmap, end, *rs); 492 *re = find_next_zero_bit(bitmap, end, *rs + 1); 493} 494 495/** 496 * BITMAP_FROM_U64() - Represent u64 value in the format suitable for bitmap. 497 * @n: u64 value 498 * 499 * Linux bitmaps are internally arrays of unsigned longs, i.e. 32-bit 500 * integers in 32-bit environment, and 64-bit integers in 64-bit one. 501 * 502 * There are four combinations of endianness and length of the word in linux 503 * ABIs: LE64, BE64, LE32 and BE32. 504 * 505 * On 64-bit kernels 64-bit LE and BE numbers are naturally ordered in 506 * bitmaps and therefore don't require any special handling. 507 * 508 * On 32-bit kernels 32-bit LE ABI orders lo word of 64-bit number in memory 509 * prior to hi, and 32-bit BE orders hi word prior to lo. The bitmap on the 510 * other hand is represented as an array of 32-bit words and the position of 511 * bit N may therefore be calculated as: word #(N/32) and bit #(N%32) in that 512 * word. For example, bit #42 is located at 10th position of 2nd word. 513 * It matches 32-bit LE ABI, and we can simply let the compiler store 64-bit 514 * values in memory as it usually does. But for BE we need to swap hi and lo 515 * words manually. 516 * 517 * With all that, the macro BITMAP_FROM_U64() does explicit reordering of hi and 518 * lo parts of u64. For LE32 it does nothing, and for BE environment it swaps 519 * hi and lo words, as is expected by bitmap. 520 */ 521#if __BITS_PER_LONG == 64 522#define BITMAP_FROM_U64(n) (n) 523#else 524#define BITMAP_FROM_U64(n) ((unsigned long) ((u64)(n) & ULONG_MAX)), \ 525 ((unsigned long) ((u64)(n) >> 32)) 526#endif 527 528/** 529 * bitmap_from_u64 - Check and swap words within u64. 530 * @mask: source bitmap 531 * @dst: destination bitmap 532 * 533 * In 32-bit Big Endian kernel, when using ``(u32 *)(&val)[*]`` 534 * to read u64 mask, we will get the wrong word. 535 * That is ``(u32 *)(&val)[0]`` gets the upper 32 bits, 536 * but we expect the lower 32-bits of u64. 537 */ 538static inline void bitmap_from_u64(unsigned long *dst, u64 mask) 539{ 540 bitmap_from_arr64(dst, &mask, 64); 541} 542 543/** 544 * bitmap_get_value8 - get an 8-bit value within a memory region 545 * @map: address to the bitmap memory region 546 * @start: bit offset of the 8-bit value; must be a multiple of 8 547 * 548 * Returns the 8-bit value located at the @start bit offset within the @src 549 * memory region. 550 */ 551static inline unsigned long bitmap_get_value8(const unsigned long *map, 552 unsigned long start) 553{ 554 const size_t index = BIT_WORD(start); 555 const unsigned long offset = start % BITS_PER_LONG; 556 557 return (map[index] >> offset) & 0xFF; 558} 559 560/** 561 * bitmap_set_value8 - set an 8-bit value within a memory region 562 * @map: address to the bitmap memory region 563 * @value: the 8-bit value; values wider than 8 bits may clobber bitmap 564 * @start: bit offset of the 8-bit value; must be a multiple of 8 565 */ 566static inline void bitmap_set_value8(unsigned long *map, unsigned long value, 567 unsigned long start) 568{ 569 const size_t index = BIT_WORD(start); 570 const unsigned long offset = start % BITS_PER_LONG; 571 572 map[index] &= ~(0xFFUL << offset); 573 map[index] |= value << offset; 574} 575 576#endif /* __ASSEMBLY__ */ 577 578#endif /* __LINUX_BITMAP_H */