bitmap.h 9.9 KB

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  1. #ifndef __LINUX_BITMAP_H
  2. #define __LINUX_BITMAP_H
  3. #ifndef __ASSEMBLY__
  4. #include <linux/types.h>
  5. #include <linux/bitops.h>
  6. #include <linux/string.h>
  7. #include <linux/kernel.h>
  8. /*
  9. * bitmaps provide bit arrays that consume one or more unsigned
  10. * longs. The bitmap interface and available operations are listed
  11. * here, in bitmap.h
  12. *
  13. * Function implementations generic to all architectures are in
  14. * lib/bitmap.c. Functions implementations that are architecture
  15. * specific are in various include/asm-<arch>/bitops.h headers
  16. * and other arch/<arch> specific files.
  17. *
  18. * See lib/bitmap.c for more details.
  19. */
  20. /*
  21. * The available bitmap operations and their rough meaning in the
  22. * case that the bitmap is a single unsigned long are thus:
  23. *
  24. * Note that nbits should be always a compile time evaluable constant.
  25. * Otherwise many inlines will generate horrible code.
  26. *
  27. * bitmap_zero(dst, nbits) *dst = 0UL
  28. * bitmap_fill(dst, nbits) *dst = ~0UL
  29. * bitmap_copy(dst, src, nbits) *dst = *src
  30. * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2
  31. * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2
  32. * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2
  33. * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2)
  34. * bitmap_complement(dst, src, nbits) *dst = ~(*src)
  35. * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal?
  36. * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap?
  37. * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2?
  38. * bitmap_empty(src, nbits) Are all bits zero in *src?
  39. * bitmap_full(src, nbits) Are all bits set in *src?
  40. * bitmap_weight(src, nbits) Hamming Weight: number set bits
  41. * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
  42. * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
  43. * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
  44. * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
  45. * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
  46. * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz
  47. * bitmap_scnprintf(buf, len, src, nbits) Print bitmap src to buf
  48. * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
  49. * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
  50. * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf
  51. * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from list
  52. * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
  53. * bitmap_release_region(bitmap, pos, order) Free specified bit region
  54. * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
  55. */
  56. /*
  57. * Also the following operations in asm/bitops.h apply to bitmaps.
  58. *
  59. * set_bit(bit, addr) *addr |= bit
  60. * clear_bit(bit, addr) *addr &= ~bit
  61. * change_bit(bit, addr) *addr ^= bit
  62. * test_bit(bit, addr) Is bit set in *addr?
  63. * test_and_set_bit(bit, addr) Set bit and return old value
  64. * test_and_clear_bit(bit, addr) Clear bit and return old value
  65. * test_and_change_bit(bit, addr) Change bit and return old value
  66. * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
  67. * find_first_bit(addr, nbits) Position first set bit in *addr
  68. * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
  69. * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
  70. */
  71. /*
  72. * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
  73. * to declare an array named 'name' of just enough unsigned longs to
  74. * contain all bit positions from 0 to 'bits' - 1.
  75. */
  76. /*
  77. * lib/bitmap.c provides these functions:
  78. */
  79. extern int __bitmap_empty(const unsigned long *bitmap, int bits);
  80. extern int __bitmap_full(const unsigned long *bitmap, int bits);
  81. extern int __bitmap_equal(const unsigned long *bitmap1,
  82. const unsigned long *bitmap2, int bits);
  83. extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
  84. int bits);
  85. extern void __bitmap_shift_right(unsigned long *dst,
  86. const unsigned long *src, int shift, int bits);
  87. extern void __bitmap_shift_left(unsigned long *dst,
  88. const unsigned long *src, int shift, int bits);
  89. extern void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
  90. const unsigned long *bitmap2, int bits);
  91. extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
  92. const unsigned long *bitmap2, int bits);
  93. extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
  94. const unsigned long *bitmap2, int bits);
  95. extern void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
  96. const unsigned long *bitmap2, int bits);
  97. extern int __bitmap_intersects(const unsigned long *bitmap1,
  98. const unsigned long *bitmap2, int bits);
  99. extern int __bitmap_subset(const unsigned long *bitmap1,
  100. const unsigned long *bitmap2, int bits);
  101. extern int __bitmap_weight(const unsigned long *bitmap, int bits);
  102. extern int bitmap_scnprintf(char *buf, unsigned int len,
  103. const unsigned long *src, int nbits);
  104. extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
  105. unsigned long *dst, int nbits);
  106. extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
  107. unsigned long *dst, int nbits);
  108. extern int bitmap_scnlistprintf(char *buf, unsigned int len,
  109. const unsigned long *src, int nbits);
  110. extern int bitmap_parselist(const char *buf, unsigned long *maskp,
  111. int nmaskbits);
  112. extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
  113. const unsigned long *old, const unsigned long *new, int bits);
  114. extern int bitmap_bitremap(int oldbit,
  115. const unsigned long *old, const unsigned long *new, int bits);
  116. extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
  117. const unsigned long *relmap, int bits);
  118. extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
  119. int sz, int bits);
  120. extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
  121. extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
  122. extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
  123. #define BITMAP_LAST_WORD_MASK(nbits) \
  124. ( \
  125. ((nbits) % BITS_PER_LONG) ? \
  126. (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
  127. )
  128. static inline void bitmap_zero(unsigned long *dst, int nbits)
  129. {
  130. if (nbits <= BITS_PER_LONG)
  131. *dst = 0UL;
  132. else {
  133. int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
  134. memset(dst, 0, len);
  135. }
  136. }
  137. static inline void bitmap_fill(unsigned long *dst, int nbits)
  138. {
  139. size_t nlongs = BITS_TO_LONGS(nbits);
  140. if (nlongs > 1) {
  141. int len = (nlongs - 1) * sizeof(unsigned long);
  142. memset(dst, 0xff, len);
  143. }
  144. dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
  145. }
  146. static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
  147. int nbits)
  148. {
  149. if (nbits <= BITS_PER_LONG)
  150. *dst = *src;
  151. else {
  152. int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
  153. memcpy(dst, src, len);
  154. }
  155. }
  156. static inline void bitmap_and(unsigned long *dst, const unsigned long *src1,
  157. const unsigned long *src2, int nbits)
  158. {
  159. if (nbits <= BITS_PER_LONG)
  160. *dst = *src1 & *src2;
  161. else
  162. __bitmap_and(dst, src1, src2, nbits);
  163. }
  164. static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
  165. const unsigned long *src2, int nbits)
  166. {
  167. if (nbits <= BITS_PER_LONG)
  168. *dst = *src1 | *src2;
  169. else
  170. __bitmap_or(dst, src1, src2, nbits);
  171. }
  172. static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
  173. const unsigned long *src2, int nbits)
  174. {
  175. if (nbits <= BITS_PER_LONG)
  176. *dst = *src1 ^ *src2;
  177. else
  178. __bitmap_xor(dst, src1, src2, nbits);
  179. }
  180. static inline void bitmap_andnot(unsigned long *dst, const unsigned long *src1,
  181. const unsigned long *src2, int nbits)
  182. {
  183. if (nbits <= BITS_PER_LONG)
  184. *dst = *src1 & ~(*src2);
  185. else
  186. __bitmap_andnot(dst, src1, src2, nbits);
  187. }
  188. static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
  189. int nbits)
  190. {
  191. if (nbits <= BITS_PER_LONG)
  192. *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits);
  193. else
  194. __bitmap_complement(dst, src, nbits);
  195. }
  196. static inline int bitmap_equal(const unsigned long *src1,
  197. const unsigned long *src2, int nbits)
  198. {
  199. if (nbits <= BITS_PER_LONG)
  200. return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
  201. else
  202. return __bitmap_equal(src1, src2, nbits);
  203. }
  204. static inline int bitmap_intersects(const unsigned long *src1,
  205. const unsigned long *src2, int nbits)
  206. {
  207. if (nbits <= BITS_PER_LONG)
  208. return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
  209. else
  210. return __bitmap_intersects(src1, src2, nbits);
  211. }
  212. static inline int bitmap_subset(const unsigned long *src1,
  213. const unsigned long *src2, int nbits)
  214. {
  215. if (nbits <= BITS_PER_LONG)
  216. return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
  217. else
  218. return __bitmap_subset(src1, src2, nbits);
  219. }
  220. static inline int bitmap_empty(const unsigned long *src, int nbits)
  221. {
  222. if (nbits <= BITS_PER_LONG)
  223. return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
  224. else
  225. return __bitmap_empty(src, nbits);
  226. }
  227. static inline int bitmap_full(const unsigned long *src, int nbits)
  228. {
  229. if (nbits <= BITS_PER_LONG)
  230. return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
  231. else
  232. return __bitmap_full(src, nbits);
  233. }
  234. static inline int bitmap_weight(const unsigned long *src, int nbits)
  235. {
  236. if (nbits <= BITS_PER_LONG)
  237. return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
  238. return __bitmap_weight(src, nbits);
  239. }
  240. static inline void bitmap_shift_right(unsigned long *dst,
  241. const unsigned long *src, int n, int nbits)
  242. {
  243. if (nbits <= BITS_PER_LONG)
  244. *dst = *src >> n;
  245. else
  246. __bitmap_shift_right(dst, src, n, nbits);
  247. }
  248. static inline void bitmap_shift_left(unsigned long *dst,
  249. const unsigned long *src, int n, int nbits)
  250. {
  251. if (nbits <= BITS_PER_LONG)
  252. *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
  253. else
  254. __bitmap_shift_left(dst, src, n, nbits);
  255. }
  256. static inline int bitmap_parse(const char *buf, unsigned int buflen,
  257. unsigned long *maskp, int nmaskbits)
  258. {
  259. return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
  260. }
  261. #endif /* __ASSEMBLY__ */
  262. #endif /* __LINUX_BITMAP_H */