LXR linux/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
  22static 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
  29typedef int32_t         efs_block_t;
  30typedef 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 */
  37typedef 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
  47typedef 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 */
  56struct  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 */
  76struct 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
  89struct 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
 101struct 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
 118static inline struct efs_inode_info *INODE_INFO(struct inode *inode)
 119{
 120        return container_of(inode, struct efs_inode_info, vfs_inode);
 121}
 122
 123static inline struct efs_sb_info *SUPER_INFO(struct super_block *sb)
 124{
 125        return sb->s_fs_info;
 126}
 127
 128struct statfs;
 129struct fid;
 130
 131extern const struct inode_operations efs_dir_inode_operations;
 132extern const struct file_operations efs_dir_operations;
 133extern const struct address_space_operations efs_symlink_aops;
 134
 135extern struct inode *efs_iget(struct super_block *, unsigned long);
 136extern efs_block_t efs_map_block(struct inode *, efs_block_t);
 137extern int efs_get_block(struct inode *, sector_t, struct buffer_head *, int);
 138
 139extern struct dentry *efs_lookup(struct inode *, struct dentry *, unsigned int);
 140extern struct dentry *efs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 141                int fh_len, int fh_type);
 142extern struct dentry *efs_fh_to_parent(struct super_block *sb, struct fid *fid,
 143                int fh_len, int fh_type);
 144extern struct dentry *efs_get_parent(struct dentry *);
 145extern int efs_bmap(struct inode *, int);
 146
 147#endif /* _EFS_EFS_H_ */
 148