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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 | /* SPDX-License-Identifier: GPL-2.0 */ /* * An extensible bitmap is a bitmap that supports an * arbitrary number of bits. Extensible bitmaps are * used to represent sets of values, such as types, * roles, categories, and classes. * * Each extensible bitmap is implemented as a linked * list of bitmap nodes, where each bitmap node has * an explicitly specified starting bit position within * the total bitmap. * * Author : Stephen Smalley, <sds@tycho.nsa.gov> */ #ifndef _SS_EBITMAP_H_ #define _SS_EBITMAP_H_ #include <net/netlabel.h> #ifdef CONFIG_64BIT #define EBITMAP_NODE_SIZE 64 #else #define EBITMAP_NODE_SIZE 32 #endif #define EBITMAP_UNIT_NUMS ((EBITMAP_NODE_SIZE-sizeof(void *)-sizeof(u32))\ / sizeof(unsigned long)) #define EBITMAP_UNIT_SIZE BITS_PER_LONG #define EBITMAP_SIZE (EBITMAP_UNIT_NUMS * EBITMAP_UNIT_SIZE) #define EBITMAP_BIT 1ULL #define EBITMAP_SHIFT_UNIT_SIZE(x) \ (((x) >> EBITMAP_UNIT_SIZE / 2) >> EBITMAP_UNIT_SIZE / 2) struct ebitmap_node { struct ebitmap_node *next; unsigned long maps[EBITMAP_UNIT_NUMS]; u32 startbit; }; struct ebitmap { struct ebitmap_node *node; /* first node in the bitmap */ u32 highbit; /* highest position in the total bitmap */ }; #define ebitmap_length(e) ((e)->highbit) static inline unsigned int ebitmap_start_positive(const struct ebitmap *e, struct ebitmap_node **n) { unsigned int ofs; for (*n = e->node; *n; *n = (*n)->next) { ofs = find_first_bit((*n)->maps, EBITMAP_SIZE); if (ofs < EBITMAP_SIZE) return (*n)->startbit + ofs; } return ebitmap_length(e); } static inline void ebitmap_init(struct ebitmap *e) { memset(e, 0, sizeof(*e)); } static inline unsigned int ebitmap_next_positive(const struct ebitmap *e, struct ebitmap_node **n, unsigned int bit) { unsigned int ofs; ofs = find_next_bit((*n)->maps, EBITMAP_SIZE, bit - (*n)->startbit + 1); if (ofs < EBITMAP_SIZE) return ofs + (*n)->startbit; for (*n = (*n)->next; *n; *n = (*n)->next) { ofs = find_first_bit((*n)->maps, EBITMAP_SIZE); if (ofs < EBITMAP_SIZE) return ofs + (*n)->startbit; } return ebitmap_length(e); } #define EBITMAP_NODE_INDEX(node, bit) \ (((bit) - (node)->startbit) / EBITMAP_UNIT_SIZE) #define EBITMAP_NODE_OFFSET(node, bit) \ (((bit) - (node)->startbit) % EBITMAP_UNIT_SIZE) static inline int ebitmap_node_get_bit(const struct ebitmap_node *n, unsigned int bit) { unsigned int index = EBITMAP_NODE_INDEX(n, bit); unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit); BUG_ON(index >= EBITMAP_UNIT_NUMS); if ((n->maps[index] & (EBITMAP_BIT << ofs))) return 1; return 0; } static inline void ebitmap_node_set_bit(struct ebitmap_node *n, unsigned int bit) { unsigned int index = EBITMAP_NODE_INDEX(n, bit); unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit); BUG_ON(index >= EBITMAP_UNIT_NUMS); n->maps[index] |= (EBITMAP_BIT << ofs); } static inline void ebitmap_node_clr_bit(struct ebitmap_node *n, unsigned int bit) { unsigned int index = EBITMAP_NODE_INDEX(n, bit); unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit); BUG_ON(index >= EBITMAP_UNIT_NUMS); n->maps[index] &= ~(EBITMAP_BIT << ofs); } #define ebitmap_for_each_positive_bit(e, n, bit) \ for ((bit) = ebitmap_start_positive(e, &(n)); \ (bit) < ebitmap_length(e); \ (bit) = ebitmap_next_positive(e, &(n), bit)) \ int ebitmap_cmp(const struct ebitmap *e1, const struct ebitmap *e2); int ebitmap_cpy(struct ebitmap *dst, const struct ebitmap *src); int ebitmap_and(struct ebitmap *dst, const struct ebitmap *e1, const struct ebitmap *e2); int ebitmap_contains(const struct ebitmap *e1, const struct ebitmap *e2, u32 last_e2bit); int ebitmap_get_bit(const struct ebitmap *e, unsigned long bit); int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value); void ebitmap_destroy(struct ebitmap *e); int ebitmap_read(struct ebitmap *e, void *fp); int ebitmap_write(const struct ebitmap *e, void *fp); u32 ebitmap_hash(const struct ebitmap *e, u32 hash); #ifdef CONFIG_NETLABEL int ebitmap_netlbl_export(struct ebitmap *ebmap, struct netlbl_lsm_catmap **catmap); int ebitmap_netlbl_import(struct ebitmap *ebmap, struct netlbl_lsm_catmap *catmap); #else static inline int ebitmap_netlbl_export(struct ebitmap *ebmap, struct netlbl_lsm_catmap **catmap) { return -ENOMEM; } static inline int ebitmap_netlbl_import(struct ebitmap *ebmap, struct netlbl_lsm_catmap *catmap) { return -ENOMEM; } #endif #endif /* _SS_EBITMAP_H_ */ |