bitmap.h 9.5 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285
  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_scnprintf(buf, len, src, nbits) Print bitmap src to buf
  46. * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
  47. * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
  48. * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf
  49. * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from list
  50. * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
  51. * bitmap_release_region(bitmap, pos, order) Free specified bit region
  52. * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
  53. */
  54. /*
  55. * Also the following operations in asm/bitops.h apply to bitmaps.
  56. *
  57. * set_bit(bit, addr) *addr |= bit
  58. * clear_bit(bit, addr) *addr &= ~bit
  59. * change_bit(bit, addr) *addr ^= bit
  60. * test_bit(bit, addr) Is bit set in *addr?
  61. * test_and_set_bit(bit, addr) Set bit and return old value
  62. * test_and_clear_bit(bit, addr) Clear bit and return old value
  63. * test_and_change_bit(bit, addr) Change bit and return old value
  64. * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
  65. * find_first_bit(addr, nbits) Position first set bit in *addr
  66. * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
  67. * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
  68. */
  69. /*
  70. * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
  71. * to declare an array named 'name' of just enough unsigned longs to
  72. * contain all bit positions from 0 to 'bits' - 1.
  73. */
  74. /*
  75. * lib/bitmap.c provides these functions:
  76. */
  77. extern int __bitmap_empty(const unsigned long *bitmap, int bits);
  78. extern int __bitmap_full(const unsigned long *bitmap, int bits);
  79. extern int __bitmap_equal(const unsigned long *bitmap1,
  80. const unsigned long *bitmap2, int bits);
  81. extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
  82. int bits);
  83. extern void __bitmap_shift_right(unsigned long *dst,
  84. const unsigned long *src, int shift, int bits);
  85. extern void __bitmap_shift_left(unsigned long *dst,
  86. const unsigned long *src, int shift, int bits);
  87. extern void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
  88. const unsigned long *bitmap2, int bits);
  89. extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
  90. const unsigned long *bitmap2, int bits);
  91. extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
  92. const unsigned long *bitmap2, int bits);
  93. extern void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
  94. const unsigned long *bitmap2, int bits);
  95. extern int __bitmap_intersects(const unsigned long *bitmap1,
  96. const unsigned long *bitmap2, int bits);
  97. extern int __bitmap_subset(const unsigned long *bitmap1,
  98. const unsigned long *bitmap2, int bits);
  99. extern int __bitmap_weight(const unsigned long *bitmap, int bits);
  100. extern int bitmap_scnprintf(char *buf, unsigned int len,
  101. const unsigned long *src, int nbits);
  102. extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
  103. unsigned long *dst, int nbits);
  104. extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
  105. unsigned long *dst, int nbits);
  106. extern int bitmap_scnlistprintf(char *buf, unsigned int len,
  107. const unsigned long *src, int nbits);
  108. extern int bitmap_parselist(const char *buf, unsigned long *maskp,
  109. int nmaskbits);
  110. extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
  111. const unsigned long *old, const unsigned long *new, int bits);
  112. extern int bitmap_bitremap(int oldbit,
  113. const unsigned long *old, const unsigned long *new, int bits);
  114. extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
  115. extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
  116. extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
  117. #define BITMAP_LAST_WORD_MASK(nbits) \
  118. ( \
  119. ((nbits) % BITS_PER_LONG) ? \
  120. (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
  121. )
  122. static inline void bitmap_zero(unsigned long *dst, int nbits)
  123. {
  124. if (nbits <= BITS_PER_LONG)
  125. *dst = 0UL;
  126. else {
  127. int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
  128. memset(dst, 0, len);
  129. }
  130. }
  131. static inline void bitmap_fill(unsigned long *dst, int nbits)
  132. {
  133. size_t nlongs = BITS_TO_LONGS(nbits);
  134. if (nlongs > 1) {
  135. int len = (nlongs - 1) * sizeof(unsigned long);
  136. memset(dst, 0xff, len);
  137. }
  138. dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
  139. }
  140. static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
  141. int nbits)
  142. {
  143. if (nbits <= BITS_PER_LONG)
  144. *dst = *src;
  145. else {
  146. int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
  147. memcpy(dst, src, len);
  148. }
  149. }
  150. static inline void bitmap_and(unsigned long *dst, const unsigned long *src1,
  151. const unsigned long *src2, int nbits)
  152. {
  153. if (nbits <= BITS_PER_LONG)
  154. *dst = *src1 & *src2;
  155. else
  156. __bitmap_and(dst, src1, src2, nbits);
  157. }
  158. static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
  159. const unsigned long *src2, int nbits)
  160. {
  161. if (nbits <= BITS_PER_LONG)
  162. *dst = *src1 | *src2;
  163. else
  164. __bitmap_or(dst, src1, src2, nbits);
  165. }
  166. static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
  167. const unsigned long *src2, int nbits)
  168. {
  169. if (nbits <= BITS_PER_LONG)
  170. *dst = *src1 ^ *src2;
  171. else
  172. __bitmap_xor(dst, src1, src2, nbits);
  173. }
  174. static inline void bitmap_andnot(unsigned long *dst, const unsigned long *src1,
  175. const unsigned long *src2, int nbits)
  176. {
  177. if (nbits <= BITS_PER_LONG)
  178. *dst = *src1 & ~(*src2);
  179. else
  180. __bitmap_andnot(dst, src1, src2, nbits);
  181. }
  182. static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
  183. int nbits)
  184. {
  185. if (nbits <= BITS_PER_LONG)
  186. *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits);
  187. else
  188. __bitmap_complement(dst, src, nbits);
  189. }
  190. static inline int bitmap_equal(const unsigned long *src1,
  191. const unsigned long *src2, int nbits)
  192. {
  193. if (nbits <= BITS_PER_LONG)
  194. return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
  195. else
  196. return __bitmap_equal(src1, src2, nbits);
  197. }
  198. static inline int bitmap_intersects(const unsigned long *src1,
  199. const unsigned long *src2, int nbits)
  200. {
  201. if (nbits <= BITS_PER_LONG)
  202. return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
  203. else
  204. return __bitmap_intersects(src1, src2, nbits);
  205. }
  206. static inline int bitmap_subset(const unsigned long *src1,
  207. const unsigned long *src2, int nbits)
  208. {
  209. if (nbits <= BITS_PER_LONG)
  210. return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
  211. else
  212. return __bitmap_subset(src1, src2, nbits);
  213. }
  214. static inline int bitmap_empty(const unsigned long *src, int nbits)
  215. {
  216. if (nbits <= BITS_PER_LONG)
  217. return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
  218. else
  219. return __bitmap_empty(src, nbits);
  220. }
  221. static inline int bitmap_full(const unsigned long *src, int nbits)
  222. {
  223. if (nbits <= BITS_PER_LONG)
  224. return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
  225. else
  226. return __bitmap_full(src, nbits);
  227. }
  228. static inline int bitmap_weight(const unsigned long *src, int nbits)
  229. {
  230. if (nbits <= BITS_PER_LONG)
  231. return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
  232. return __bitmap_weight(src, nbits);
  233. }
  234. static inline void bitmap_shift_right(unsigned long *dst,
  235. const unsigned long *src, int n, int nbits)
  236. {
  237. if (nbits <= BITS_PER_LONG)
  238. *dst = *src >> n;
  239. else
  240. __bitmap_shift_right(dst, src, n, nbits);
  241. }
  242. static inline void bitmap_shift_left(unsigned long *dst,
  243. const unsigned long *src, int n, int nbits)
  244. {
  245. if (nbits <= BITS_PER_LONG)
  246. *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
  247. else
  248. __bitmap_shift_left(dst, src, n, nbits);
  249. }
  250. static inline int bitmap_parse(const char *buf, unsigned int buflen,
  251. unsigned long *maskp, int nmaskbits)
  252. {
  253. return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
  254. }
  255. #endif /* __ASSEMBLY__ */
  256. #endif /* __LINUX_BITMAP_H */