fs/efs/efs.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright (c) 1999 Al Smith
   4  *
   5  * Portions derived from work (c) 1995,1996 Christian Vogelgsang.
   6  * Portions derived from IRIX header files (c) 1988 Silicon Graphics
   7  */
   8 #ifndef _EFS_EFS_H_
   9 #define _EFS_EFS_H_
  10
  11 #ifdef pr_fmt
  12 #undef pr_fmt
  13 #endif
  14
  15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  16
  17 #include <linux/fs.h>
  18 #include <linux/uaccess.h>
  19
  20 #define EFS_VERSION "1.0a"
  21
  22 static const char cprt[] = "EFS: "EFS_VERSION" - (c) 1999 Al Smith <Al.Smith@aeschi.ch.eu.org>";
  23
  24
  25 /* 1 block is 512 bytes */
  26 #define EFS_BLOCKSIZE_BITS      9
  27 #define EFS_BLOCKSIZE           (1 << EFS_BLOCKSIZE_BITS)
  28
  29 typedef int32_t         efs_block_t;
  30 typedef uint32_t        efs_ino_t;
  31
  32 #define EFS_DIRECTEXTENTS       12
  33
  34 /*
  35  * layout of an extent, in memory and on disk. 8 bytes exactly.
  36  */
  37 typedef union extent_u {
  38         unsigned char raw[8];
  39         struct extent_s {
  40                 unsigned int    ex_magic:8;     /* magic # (zero) */
  41                 unsigned int    ex_bn:24;       /* basic block */
  42                 unsigned int    ex_length:8;    /* numblocks in this extent */
  43                 unsigned int    ex_offset:24;   /* logical offset into file */
  44         } cooked;
  45 } efs_extent;
  46
  47 typedef struct edevs {
  48         __be16          odev;
  49         __be32          ndev;
  50 } efs_devs;
  51
  52 /*
  53  * extent based filesystem inode as it appears on disk.  The efs inode
  54  * is exactly 128 bytes long.
  55  */
  56 struct  efs_dinode {
  57         __be16          di_mode;        /* mode and type of file */
  58         __be16          di_nlink;       /* number of links to file */
  59         __be16          di_uid;         /* owner's user id */
  60         __be16          di_gid;         /* owner's group id */
  61         __be32          di_size;        /* number of bytes in file */
  62         __be32          di_atime;       /* time last accessed */
  63         __be32          di_mtime;       /* time last modified */
  64         __be32          di_ctime;       /* time created */
  65         __be32          di_gen;         /* generation number */
  66         __be16          di_numextents;  /* # of extents */
  67         u_char          di_version;     /* version of inode */
  68         u_char          di_spare;       /* spare - used by AFS */
  69         union di_addr {
  70                 efs_extent      di_extents[EFS_DIRECTEXTENTS];
  71                 efs_devs        di_dev; /* device for IFCHR/IFBLK */
  72         } di_u;
  73 };
  74
  75 /* efs inode storage in memory */
  76 struct efs_inode_info {
  77         int             numextents;
  78         int             lastextent;
  79
  80         efs_extent      extents[EFS_DIRECTEXTENTS];
  81         struct inode    vfs_inode;
  82 };
  83
  84 #include <linux/efs_fs_sb.h>
  85
  86 #define EFS_DIRBSIZE_BITS       EFS_BLOCKSIZE_BITS
  87 #define EFS_DIRBSIZE            (1 << EFS_DIRBSIZE_BITS)
  88
  89 struct efs_dentry {
  90         __be32          inode;
  91         unsigned char   namelen;
  92         char            name[3];
  93 };
  94
  95 #define EFS_DENTSIZE    (sizeof(struct efs_dentry) - 3 + 1)
  96 #define EFS_MAXNAMELEN  ((1 << (sizeof(char) * 8)) - 1)
  97
  98 #define EFS_DIRBLK_HEADERSIZE   4
  99 #define EFS_DIRBLK_MAGIC        0xbeef  /* moo */
 100
 101 struct efs_dir {
 102         __be16  magic;
 103         unsigned char   firstused;
 104         unsigned char   slots;
 105
 106         unsigned char   space[EFS_DIRBSIZE - EFS_DIRBLK_HEADERSIZE];
 107 };
 108
 109 #define EFS_MAXENTS \
 110         ((EFS_DIRBSIZE - EFS_DIRBLK_HEADERSIZE) / \
 111          (EFS_DENTSIZE + sizeof(char)))
 112
 113 #define EFS_SLOTAT(dir, slot) EFS_REALOFF((dir)->space[slot])
 114
 115 #define EFS_REALOFF(offset) ((offset << 1))
 116
 117
 118 static inline struct efs_inode_info *INODE_INFO(struct inode *inode)
 119 {
 120         return container_of(inode, struct efs_inode_info, vfs_inode);
 121 }
 122
 123 static inline struct efs_sb_info *SUPER_INFO(struct super_block *sb)
 124 {
 125         return sb->s_fs_info;
 126 }
 127
 128 struct statfs;
 129 struct fid;
 130
 131 extern const struct inode_operations efs_dir_inode_operations;
 132 extern const struct file_operations efs_dir_operations;
 133 extern const struct address_space_operations efs_symlink_aops;
 134
 135 extern struct inode *efs_iget(struct super_block *, unsigned long);
 136 extern efs_block_t efs_map_block(struct inode *, efs_block_t);
 137 extern int efs_get_block(struct inode *, sector_t, struct buffer_head *, int);
 138
 139 extern struct dentry *efs_lookup(struct inode *, struct dentry *, unsigned int);
 140 extern struct dentry *efs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 141                 int fh_len, int fh_type);
 142 extern struct dentry *efs_fh_to_parent(struct super_block *sb, struct fid *fid,
 143                 int fh_len, int fh_type);
 144 extern struct dentry *efs_get_parent(struct dentry *);
 145 extern int efs_bmap(struct inode *, int);
 146
 147 #endif /* _EFS_EFS_H_ */