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
  15 static 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
  22 typedef int32_t         efs_block_t;
  23 typedef 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  */
  30 typedef 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
  40 typedef 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  */
  49 struct  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 */
  69 struct 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
  82 struct 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
  94 struct 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
 111 static inline struct efs_inode_info *INODE_INFO(struct inode *inode)
 112 {
 113         return container_of(inode, struct efs_inode_info, vfs_inode);
 114 }
 115
 116 static inline struct efs_sb_info *SUPER_INFO(struct super_block *sb)
 117 {
 118         return sb->s_fs_info;
 119 }
 120
 121 struct statfs;
 122 struct fid;
 123
 124 extern const struct inode_operations efs_dir_inode_operations;
 125 extern const struct file_operations efs_dir_operations;
 126 extern const struct address_space_operations efs_symlink_aops;
 127
 128 extern struct inode *efs_iget(struct super_block *, unsigned long);
 129 extern efs_block_t efs_map_block(struct inode *, efs_block_t);
 130 extern int efs_get_block(struct inode *, sector_t, struct buffer_head *, int);
 131
 132 extern struct dentry *efs_lookup(struct inode *, struct dentry *, struct nameidata *);
 133 extern struct dentry *efs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 134                 int fh_len, int fh_type);
 135 extern struct dentry *efs_fh_to_parent(struct super_block *sb, struct fid *fid,
 136                 int fh_len, int fh_type);
 137 extern struct dentry *efs_get_parent(struct dentry *);
 138 extern int efs_bmap(struct inode *, int);
 139
 140 #endif /* _EFS_EFS_H_ */