LXR linux/fs/efs/efs.h

   1/*
   2 * Copyright (c) 1999 Al Smith
   3 *
   4 * Portions derived from work (c) 1995,1996 Christian Vogelgsang.
   5 * Portions derived from IRIX header files (c) 1988 Silicon Graphics
   6 */
   7#ifndef _EFS_EFS_H_
   8#define _EFS_EFS_H_
   9
  10#include <linux/fs.h>
  11#include <asm/uaccess.h>
  12
  13#define EFS_VERSION "1.0a"
  14
  15static const char cprt[] = "EFS: "EFS_VERSION" - (c) 1999 Al Smith <Al.Smith@aeschi.ch.eu.org>";
  16
  17
  18/* 1 block is 512 bytes */
  19#define EFS_BLOCKSIZE_BITS      9
  20#define EFS_BLOCKSIZE           (1 << EFS_BLOCKSIZE_BITS)
  21
  22typedef int32_t         efs_block_t;
  23typedef uint32_t        efs_ino_t;
  24
  25#define EFS_DIRECTEXTENTS       12
  26
  27/*
  28 * layout of an extent, in memory and on disk. 8 bytes exactly.
  29 */
  30typedef union extent_u {
  31        unsigned char raw[8];
  32        struct extent_s {
  33                unsigned int    ex_magic:8;     /* magic # (zero) */
  34                unsigned int    ex_bn:24;       /* basic block */
  35                unsigned int    ex_length:8;    /* numblocks in this extent */
  36                unsigned int    ex_offset:24;   /* logical offset into file */
  37        } cooked;
  38} efs_extent;
  39
  40typedef struct edevs {
  41        __be16          odev;
  42        __be32          ndev;
  43} efs_devs;
  44
  45/*
  46 * extent based filesystem inode as it appears on disk.  The efs inode
  47 * is exactly 128 bytes long.
  48 */
  49struct  efs_dinode {
  50        __be16          di_mode;        /* mode and type of file */
  51        __be16          di_nlink;       /* number of links to file */
  52        __be16          di_uid;         /* owner's user id */
  53        __be16          di_gid;         /* owner's group id */
  54        __be32          di_size;        /* number of bytes in file */
  55        __be32          di_atime;       /* time last accessed */
  56        __be32          di_mtime;       /* time last modified */
  57        __be32          di_ctime;       /* time created */
  58        __be32          di_gen;         /* generation number */
  59        __be16          di_numextents;  /* # of extents */
  60        u_char          di_version;     /* version of inode */
  61        u_char          di_spare;       /* spare - used by AFS */
  62        union di_addr {
  63                efs_extent      di_extents[EFS_DIRECTEXTENTS];
  64                efs_devs        di_dev; /* device for IFCHR/IFBLK */
  65        } di_u;
  66};
  67
  68/* efs inode storage in memory */
  69struct efs_inode_info {
  70        int             numextents;
  71        int             lastextent;
  72
  73        efs_extent      extents[EFS_DIRECTEXTENTS];
  74        struct inode    vfs_inode;
  75};
  76
  77#include <linux/efs_fs_sb.h>
  78
  79#define EFS_DIRBSIZE_BITS       EFS_BLOCKSIZE_BITS
  80#define EFS_DIRBSIZE            (1 << EFS_DIRBSIZE_BITS)
  81
  82struct efs_dentry {
  83        __be32          inode;
  84        unsigned char   namelen;
  85        char            name[3];
  86};
  87
  88#define EFS_DENTSIZE    (sizeof(struct efs_dentry) - 3 + 1)
  89#define EFS_MAXNAMELEN  ((1 << (sizeof(char) * 8)) - 1)
  90
  91#define EFS_DIRBLK_HEADERSIZE   4
  92#define EFS_DIRBLK_MAGIC        0xbeef  /* moo */
  93
  94struct efs_dir {
  95        __be16  magic;
  96        unsigned char   firstused;
  97        unsigned char   slots;
  98
  99        unsigned char   space[EFS_DIRBSIZE - EFS_DIRBLK_HEADERSIZE];
 100};
 101
 102#define EFS_MAXENTS \
 103        ((EFS_DIRBSIZE - EFS_DIRBLK_HEADERSIZE) / \
 104         (EFS_DENTSIZE + sizeof(char)))
 105
 106#define EFS_SLOTAT(dir, slot) EFS_REALOFF((dir)->space[slot])
 107
 108#define EFS_REALOFF(offset) ((offset << 1))
 109
 110
 111static inline struct efs_inode_info *INODE_INFO(struct inode *inode)
 112{
 113        return container_of(inode, struct efs_inode_info, vfs_inode);
 114}
 115
 116static inline struct efs_sb_info *SUPER_INFO(struct super_block *sb)
 117{
 118        return sb->s_fs_info;
 119}
 120
 121struct statfs;
 122struct fid;
 123
 124extern const struct inode_operations efs_dir_inode_operations;
 125extern const struct file_operations efs_dir_operations;
 126extern const struct address_space_operations efs_symlink_aops;
 127
 128extern struct inode *efs_iget(struct super_block *, unsigned long);
 129extern efs_block_t efs_map_block(struct inode *, efs_block_t);
 130extern int efs_get_block(struct inode *, sector_t, struct buffer_head *, int);
 131
 132extern struct dentry *efs_lookup(struct inode *, struct dentry *, struct nameidata *);
 133extern struct dentry *efs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 134                int fh_len, int fh_type);
 135extern struct dentry *efs_fh_to_parent(struct super_block *sb, struct fid *fid,
 136                int fh_len, int fh_type);
 137extern struct dentry *efs_get_parent(struct dentry *);
 138extern int efs_bmap(struct inode *, int);
 139
 140#endif /* _EFS_EFS_H_ */
 141