2 * An extensible bitmap is a bitmap that supports an
3 * arbitrary number of bits. Extensible bitmaps are
4 * used to represent sets of values, such as types,
5 * roles, categories, and classes.
7 * Each extensible bitmap is implemented as a linked
8 * list of bitmap nodes, where each bitmap node has
9 * an explicitly specified starting bit position within
12 * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
14 #ifndef _SS_EBITMAP_H_
15 #define _SS_EBITMAP_H_
17 #include <net/netlabel.h>
19 #define EBITMAP_UNIT_NUMS ((32 - sizeof(void *) - sizeof(u32)) \
20 / sizeof(unsigned long))
21 #define EBITMAP_UNIT_SIZE BITS_PER_LONG
22 #define EBITMAP_SIZE (EBITMAP_UNIT_NUMS * EBITMAP_UNIT_SIZE)
23 #define EBITMAP_BIT 1ULL
26 struct ebitmap_node *next;
27 unsigned long maps[EBITMAP_UNIT_NUMS];
32 struct ebitmap_node *node; /* first node in the bitmap */
33 u32 highbit; /* highest position in the total bitmap */
36 #define ebitmap_length(e) ((e)->highbit)
37 #define ebitmap_startbit(e) ((e)->node ? (e)->node->startbit : 0)
39 static inline unsigned int ebitmap_start_positive(struct ebitmap *e,
40 struct ebitmap_node **n)
44 for (*n = e->node; *n; *n = (*n)->next) {
45 ofs = find_first_bit((*n)->maps, EBITMAP_SIZE);
46 if (ofs < EBITMAP_SIZE)
47 return (*n)->startbit + ofs;
49 return ebitmap_length(e);
52 static inline void ebitmap_init(struct ebitmap *e)
54 memset(e, 0, sizeof(*e));
57 static inline unsigned int ebitmap_next_positive(struct ebitmap *e,
58 struct ebitmap_node **n,
63 ofs = find_next_bit((*n)->maps, EBITMAP_SIZE, bit - (*n)->startbit + 1);
64 if (ofs < EBITMAP_SIZE)
65 return ofs + (*n)->startbit;
67 for (*n = (*n)->next; *n; *n = (*n)->next) {
68 ofs = find_first_bit((*n)->maps, EBITMAP_SIZE);
69 if (ofs < EBITMAP_SIZE)
70 return ofs + (*n)->startbit;
72 return ebitmap_length(e);
75 #define EBITMAP_NODE_INDEX(node, bit) \
76 (((bit) - (node)->startbit) / EBITMAP_UNIT_SIZE)
77 #define EBITMAP_NODE_OFFSET(node, bit) \
78 (((bit) - (node)->startbit) % EBITMAP_UNIT_SIZE)
80 static inline int ebitmap_node_get_bit(struct ebitmap_node *n,
83 unsigned int index = EBITMAP_NODE_INDEX(n, bit);
84 unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit);
86 BUG_ON(index >= EBITMAP_UNIT_NUMS);
87 if ((n->maps[index] & (EBITMAP_BIT << ofs)))
92 static inline void ebitmap_node_set_bit(struct ebitmap_node *n,
95 unsigned int index = EBITMAP_NODE_INDEX(n, bit);
96 unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit);
98 BUG_ON(index >= EBITMAP_UNIT_NUMS);
99 n->maps[index] |= (EBITMAP_BIT << ofs);
102 static inline void ebitmap_node_clr_bit(struct ebitmap_node *n,
105 unsigned int index = EBITMAP_NODE_INDEX(n, bit);
106 unsigned int ofs = EBITMAP_NODE_OFFSET(n, bit);
108 BUG_ON(index >= EBITMAP_UNIT_NUMS);
109 n->maps[index] &= ~(EBITMAP_BIT << ofs);
112 #define ebitmap_for_each_positive_bit(e, n, bit) \
113 for (bit = ebitmap_start_positive(e, &n); \
114 bit < ebitmap_length(e); \
115 bit = ebitmap_next_positive(e, &n, bit)) \
117 int ebitmap_cmp(struct ebitmap *e1, struct ebitmap *e2);
118 int ebitmap_cpy(struct ebitmap *dst, struct ebitmap *src);
119 int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2);
120 int ebitmap_get_bit(struct ebitmap *e, unsigned long bit);
121 int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value);
122 void ebitmap_destroy(struct ebitmap *e);
123 int ebitmap_read(struct ebitmap *e, void *fp);
125 #ifdef CONFIG_NETLABEL
126 int ebitmap_netlbl_export(struct ebitmap *ebmap,
127 struct netlbl_lsm_secattr_catmap **catmap);
128 int ebitmap_netlbl_import(struct ebitmap *ebmap,
129 struct netlbl_lsm_secattr_catmap *catmap);
131 static inline int ebitmap_netlbl_export(struct ebitmap *ebmap,
132 struct netlbl_lsm_secattr_catmap **catmap)
136 static inline int ebitmap_netlbl_import(struct ebitmap *ebmap,
137 struct netlbl_lsm_secattr_catmap *catmap)
143 #endif /* _SS_EBITMAP_H_ */