| /* 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, <stephen.smalley.work@gmail.com> |
| */ |
| |
| #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 u32 ebitmap_start_positive(const struct ebitmap *e, |
| struct ebitmap_node **n) |
| { |
| u32 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 u32 ebitmap_next_positive(const struct ebitmap *e, |
| struct ebitmap_node **n, u32 bit) |
| { |
| u32 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, u32 bit) |
| { |
| u32 index = EBITMAP_NODE_INDEX(n, bit); |
| u32 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, u32 bit) |
| { |
| u32 index = EBITMAP_NODE_INDEX(n, bit); |
| u32 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, u32 bit) |
| { |
| u32 index = EBITMAP_NODE_INDEX(n, bit); |
| u32 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, u32 bit); |
| int ebitmap_set_bit(struct ebitmap *e, u32 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_ */ |