153 lines
4.2 KiB
C
153 lines
4.2 KiB
C
/* 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(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(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(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(struct ebitmap *e1, struct ebitmap *e2);
|
|
int ebitmap_cpy(struct ebitmap *dst, struct ebitmap *src);
|
|
int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2, u32 last_e2bit);
|
|
int ebitmap_get_bit(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(struct ebitmap *e, void *fp);
|
|
|
|
#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_ */
|