LXR linux/include/linux/dqblk

   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;
  18struct kqid;
  19
  20/* Operations */
  21struct qtree_fmt_operations {
  22        void (*mem2disk_dqblk)(void *disk, struct dquot *dquot);        /* Convert given entry from in memory format to disk one */
  23        void (*disk2mem_dqblk)(struct dquot *dquot, void *disk);        /* Convert given entry from disk format to in memory one */
  24        int (*is_id)(void *disk, struct dquot *dquot);  /* Is this structure for given id? */
  25};
  26
  27/* Inmemory copy of version specific information */
  28struct qtree_mem_dqinfo {
  29        struct super_block *dqi_sb;     /* Sb quota is on */
  30        int dqi_type;                   /* Quota type */
  31        unsigned int dqi_blocks;        /* # of blocks in quota file */
  32        unsigned int dqi_free_blk;      /* First block in list of free blocks */
  33        unsigned int dqi_free_entry;    /* First block with free entry */
  34        unsigned int dqi_blocksize_bits;        /* Block size of quota file */
  35        unsigned int dqi_entry_size;    /* Size of quota entry in quota file */
  36        unsigned int dqi_usable_bs;     /* Space usable in block for quota data */
  37        unsigned int dqi_qtree_depth;   /* Precomputed depth of quota tree */
  38        const struct qtree_fmt_operations *dqi_ops; /* Operations for entry manipulation */
  39};
  40
  41int qtree_write_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
  42int qtree_read_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
  43int qtree_delete_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
  44int qtree_release_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot);
  45int qtree_entry_unused(struct qtree_mem_dqinfo *info, char *disk);
  46static inline int qtree_depth(struct qtree_mem_dqinfo *info)
  47{
  48        unsigned int epb = info->dqi_usable_bs >> 2;
  49        unsigned long long entries = epb;
  50        int i;
  51
  52        for (i = 1; entries < (1ULL << 32); i++)
  53                entries *= epb;
  54        return i;
  55}
  56int qtree_get_next_id(struct qtree_mem_dqinfo *info, struct kqid *qid);
  57
  58#endif /* _LINUX_DQBLK_QTREE_H */
  59