1/*
2 *	Definitions of structures and functions for quota formats using trie
3 */
4
5#ifndef _LINUX_DQBLK_QTREE_H
6#define _LINUX_DQBLK_QTREE_H
7
8#include <linux/types.h>
9
10/* Numbers of blocks needed for updates - we count with the smallest
11 * possible block size (1024) */
12#define QTREE_INIT_ALLOC 4
13#define QTREE_INIT_REWRITE 2
14#define QTREE_DEL_ALLOC 0
15#define QTREE_DEL_REWRITE 6
16
17struct dquot;
18
19/* Operations */
20struct qtree_fmt_operations {
21	void (*mem2disk_dqblk)(void *disk, struct dquot *dquot);	/* Convert given entry from in memory format to disk one */
22	void (*disk2mem_dqblk)(struct dquot *dquot, void *disk);	/* Convert given entry from disk format to in memory one */
23	int (*is_id)(void *disk, struct dquot *dquot);	/* Is this structure for given id? */
24};
25
26/* Inmemory copy of version specific information */
27struct qtree_mem_dqinfo {
28	struct super_block *dqi_sb;	/* Sb quota is on */
29	int dqi_type;			/* Quota type */
30	unsigned int dqi_blocks;	/* # of blocks in quota file */
31	unsigned int dqi_free_blk;	/* First block in list of free blocks */
32	unsigned int dqi_free_entry;	/* First block with free entry */
33	unsigned int dqi_blocksize_bits;	/* Block size of quota file */
34	unsigned int dqi_entry_size;	/* Size of quota entry in quota file */
35	unsigned int dqi_usable_bs;	/* Space usable in block for quota data */
36	unsigned int dqi_qtree_depth;	/* Precomputed depth of quota tree */
37	struct qtree_fmt_operations *dqi_ops;	/* Operations for entry manipulation */
38};
39
40int qtree_write_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
41int qtree_read_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
42int qtree_delete_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
43int qtree_release_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
44int qtree_entry_unused(struct qtree_mem_dqinfo *info, char *disk);
45static inline int qtree_depth(struct qtree_mem_dqinfo *info)
46{
47	unsigned int epb = info->dqi_usable_bs >> 2;
48	unsigned long long entries = epb;
49	int i;
50
51	for (i = 1; entries < (1ULL << 32); i++)
52		entries *= epb;
53	return i;
54}
55
56#endif /* _LINUX_DQBLK_QTREE_H */
57