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 #ifdef pr_fmt
  11 #undef pr_fmt
  12 #endif
  13
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16 #include <linux/fs.h>
  17 #include <asm/uaccess.h>
  18
  19 #define EFS_VERSION "1.0a"
  20
  21 static const char cprt[] = "EFS: "EFS_VERSION" - (c) 1999 Al Smith <Al.Smith@aeschi.ch.eu.org>";
  22
  23
  24 /* 1 block is 512 bytes */
  25 #define EFS_BLOCKSIZE_BITS      9
  26 #define EFS_BLOCKSIZE           (1 << EFS_BLOCKSIZE_BITS)
  27
  28 typedef int32_t         efs_block_t;
  29 typedef uint32_t        efs_ino_t;
  30
  31 #define EFS_DIRECTEXTENTS       12
  32
  33 /*
  34  * layout of an extent, in memory and on disk. 8 bytes exactly.
  35  */
  36 typedef union extent_u {
  37         unsigned char raw[8];
  38         struct extent_s {
  39                 unsigned int    ex_magic:8;     /* magic # (zero) */
  40                 unsigned int    ex_bn:24;       /* basic block */
  41                 unsigned int    ex_length:8;    /* numblocks in this extent */
  42                 unsigned int    ex_offset:24;   /* logical offset into file */
  43         } cooked;
  44 } efs_extent;
  45
  46 typedef struct edevs {
  47         __be16          odev;
  48         __be32          ndev;
  49 } efs_devs;
  50
  51 /*
  52  * extent based filesystem inode as it appears on disk.  The efs inode
  53  * is exactly 128 bytes long.
  54  */
  55 struct  efs_dinode {
  56         __be16          di_mode;        /* mode and type of file */
  57         __be16          di_nlink;       /* number of links to file */
  58         __be16          di_uid;         /* owner's user id */
  59         __be16          di_gid;         /* owner's group id */
  60         __be32          di_size;        /* number of bytes in file */
  61         __be32          di_atime;       /* time last accessed */
  62         __be32          di_mtime;       /* time last modified */
  63         __be32          di_ctime;       /* time created */
  64         __be32          di_gen;         /* generation number */
  65         __be16          di_numextents;  /* # of extents */
  66         u_char          di_version;     /* version of inode */
  67         u_char          di_spare;       /* spare - used by AFS */
  68         union di_addr {
  69                 efs_extent      di_extents[EFS_DIRECTEXTENTS];
  70                 efs_devs        di_dev; /* device for IFCHR/IFBLK */
  71         } di_u;
  72 };
  73
  74 /* efs inode storage in memory */
  75 struct efs_inode_info {
  76         int             numextents;
  77         int             lastextent;
  78
  79         efs_extent      extents[EFS_DIRECTEXTENTS];
  80         struct inode    vfs_inode;
  81 };
  82
  83 #include <linux/efs_fs_sb.h>
  84
  85 #define EFS_DIRBSIZE_BITS       EFS_BLOCKSIZE_BITS
  86 #define EFS_DIRBSIZE            (1 << EFS_DIRBSIZE_BITS)
  87
  88 struct efs_dentry {
  89         __be32          inode;
  90         unsigned char   namelen;
  91         char            name[3];
  92 };
  93
  94 #define EFS_DENTSIZE    (sizeof(struct efs_dentry) - 3 + 1)
  95 #define EFS_MAXNAMELEN  ((1 << (sizeof(char) * 8)) - 1)
  96
  97 #define EFS_DIRBLK_HEADERSIZE   4
  98 #define EFS_DIRBLK_MAGIC        0xbeef  /* moo */
  99
 100 struct efs_dir {
 101         __be16  magic;
 102         unsigned char   firstused;
 103         unsigned char   slots;
 104
 105         unsigned char   space[EFS_DIRBSIZE - EFS_DIRBLK_HEADERSIZE];
 106 };
 107
 108 #define EFS_MAXENTS \
 109         ((EFS_DIRBSIZE - EFS_DIRBLK_HEADERSIZE) / \
 110          (EFS_DENTSIZE + sizeof(char)))
 111
 112 #define EFS_SLOTAT(dir, slot) EFS_REALOFF((dir)->space[slot])
 113
 114 #define EFS_REALOFF(offset) ((offset << 1))
 115
 116
 117 static inline struct efs_inode_info *INODE_INFO(struct inode *inode)
 118 {
 119         return container_of(inode, struct efs_inode_info, vfs_inode);
 120 }
 121
 122 static inline struct efs_sb_info *SUPER_INFO(struct super_block *sb)
 123 {
 124         return sb->s_fs_info;
 125 }
 126
 127 struct statfs;
 128 struct fid;
 129
 130 extern const struct inode_operations efs_dir_inode_operations;
 131 extern const struct file_operations efs_dir_operations;
 132 extern const struct address_space_operations efs_symlink_aops;
 133
 134 extern struct inode *efs_iget(struct super_block *, unsigned long);
 135 extern efs_block_t efs_map_block(struct inode *, efs_block_t);
 136 extern int efs_get_block(struct inode *, sector_t, struct buffer_head *, int);
 137
 138 extern struct dentry *efs_lookup(struct inode *, struct dentry *, unsigned int);
 139 extern struct dentry *efs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 140                 int fh_len, int fh_type);
 141 extern struct dentry *efs_fh_to_parent(struct super_block *sb, struct fid *fid,
 142                 int fh_len, int fh_type);
 143 extern struct dentry *efs_get_parent(struct dentry *);
 144 extern int efs_bmap(struct inode *, int);
 145
 146 #endif /* _EFS_EFS_H_ */