xref: /openbmc/linux/include/linux/dqblk_qtree.h (revision 498495dba268b20e8eadd7fe93c140c68b6cc9d2)
1  /* SPDX-License-Identifier: GPL-2.0 */
2  /*
3   *	Definitions of structures and functions for quota formats using trie
4   */
5  
6  #ifndef _LINUX_DQBLK_QTREE_H
7  #define _LINUX_DQBLK_QTREE_H
8  
9  #include <linux/types.h>
10  
11  /* Numbers of blocks needed for updates - we count with the smallest
12   * possible block size (1024) */
13  #define QTREE_INIT_ALLOC 4
14  #define QTREE_INIT_REWRITE 2
15  #define QTREE_DEL_ALLOC 0
16  #define QTREE_DEL_REWRITE 6
17  
18  struct dquot;
19  struct kqid;
20  
21  /* Operations */
22  struct qtree_fmt_operations {
23  	void (*mem2disk_dqblk)(void *disk, struct dquot *dquot);	/* Convert given entry from in memory format to disk one */
24  	void (*disk2mem_dqblk)(struct dquot *dquot, void *disk);	/* Convert given entry from disk format to in memory one */
25  	int (*is_id)(void *disk, struct dquot *dquot);	/* Is this structure for given id? */
26  };
27  
28  /* Inmemory copy of version specific information */
29  struct qtree_mem_dqinfo {
30  	struct super_block *dqi_sb;	/* Sb quota is on */
31  	int dqi_type;			/* Quota type */
32  	unsigned int dqi_blocks;	/* # of blocks in quota file */
33  	unsigned int dqi_free_blk;	/* First block in list of free blocks */
34  	unsigned int dqi_free_entry;	/* First block with free entry */
35  	unsigned int dqi_blocksize_bits;	/* Block size of quota file */
36  	unsigned int dqi_entry_size;	/* Size of quota entry in quota file */
37  	unsigned int dqi_usable_bs;	/* Space usable in block for quota data */
38  	unsigned int dqi_qtree_depth;	/* Precomputed depth of quota tree */
39  	const struct qtree_fmt_operations *dqi_ops; /* Operations for entry manipulation */
40  };
41  
42  int qtree_write_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
43  int qtree_read_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
44  int qtree_delete_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
45  int qtree_release_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
46  int qtree_entry_unused(struct qtree_mem_dqinfo *info, char *disk);
qtree_depth(struct qtree_mem_dqinfo * info)47  static inline int qtree_depth(struct qtree_mem_dqinfo *info)
48  {
49  	unsigned int epb = info->dqi_usable_bs >> 2;
50  	unsigned long long entries = epb;
51  	int i;
52  
53  	for (i = 1; entries < (1ULL << 32); i++)
54  		entries *= epb;
55  	return i;
56  }
57  int qtree_get_next_id(struct qtree_mem_dqinfo *info, struct kqid *qid);
58  
59  #endif /* _LINUX_DQBLK_QTREE_H */
60