LXR linux/fs/isofs/isofs.h

   1#include <linux/fs.h>
   2#include <linux/buffer_head.h>
   3#include <linux/exportfs.h>
   4#include <linux/iso_fs.h>
   5#include <asm/unaligned.h>
   6
   7enum isofs_file_format {
   8        isofs_file_normal = 0,
   9        isofs_file_sparse = 1,
  10        isofs_file_compressed = 2,
  11};
  12        
  13/*
  14 * iso fs inode data in memory
  15 */
  16struct iso_inode_info {
  17        unsigned long i_iget5_block;
  18        unsigned long i_iget5_offset;
  19        unsigned int i_first_extent;
  20        unsigned char i_file_format;
  21        unsigned char i_format_parm[3];
  22        unsigned long i_next_section_block;
  23        unsigned long i_next_section_offset;
  24        off_t i_section_size;
  25        struct inode vfs_inode;
  26};
  27
  28/*
  29 * iso9660 super-block data in memory
  30 */
  31struct isofs_sb_info {
  32        unsigned long s_ninodes;
  33        unsigned long s_nzones;
  34        unsigned long s_firstdatazone;
  35        unsigned long s_log_zone_size;
  36        unsigned long s_max_size;
  37        
  38        unsigned char s_high_sierra; /* A simple flag */
  39        unsigned char s_mapping;
  40        int           s_rock_offset; /* offset of SUSP fields within SU area */
  41        unsigned char s_rock;
  42        unsigned char s_joliet_level;
  43        unsigned char s_utf8;
  44        unsigned char s_cruft; /* Broken disks with high
  45                                  byte of length containing
  46                                  junk */
  47        unsigned char s_unhide;
  48        unsigned char s_nosuid;
  49        unsigned char s_nodev;
  50        unsigned char s_nocompress;
  51        unsigned char s_hide;
  52        unsigned char s_showassoc;
  53
  54        mode_t s_fmode;
  55        mode_t s_dmode;
  56        gid_t s_gid;
  57        uid_t s_uid;
  58        struct nls_table *s_nls_iocharset; /* Native language support table */
  59};
  60
  61static inline struct isofs_sb_info *ISOFS_SB(struct super_block *sb)
  62{
  63        return sb->s_fs_info;
  64}
  65
  66static inline struct iso_inode_info *ISOFS_I(struct inode *inode)
  67{
  68        return container_of(inode, struct iso_inode_info, vfs_inode);
  69}
  70
  71static inline int isonum_711(char *p)
  72{
  73        return *(u8 *)p;
  74}
  75static inline int isonum_712(char *p)
  76{
  77        return *(s8 *)p;
  78}
  79static inline unsigned int isonum_721(char *p)
  80{
  81        return le16_to_cpu(get_unaligned((__le16 *)p));
  82}
  83static inline unsigned int isonum_722(char *p)
  84{
  85        return be16_to_cpu(get_unaligned((__le16 *)p));
  86}
  87static inline unsigned int isonum_723(char *p)
  88{
  89        /* Ignore bigendian datum due to broken mastering programs */
  90        return le16_to_cpu(get_unaligned((__le16 *)p));
  91}
  92static inline unsigned int isonum_731(char *p)
  93{
  94        return le32_to_cpu(get_unaligned((__le32 *)p));
  95}
  96static inline unsigned int isonum_732(char *p)
  97{
  98        return be32_to_cpu(get_unaligned((__le32 *)p));
  99}
 100static inline unsigned int isonum_733(char *p)
 101{
 102        /* Ignore bigendian datum due to broken mastering programs */
 103        return le32_to_cpu(get_unaligned((__le32 *)p));
 104}
 105extern int iso_date(char *, int);
 106
 107struct inode;           /* To make gcc happy */
 108
 109extern int parse_rock_ridge_inode(struct iso_directory_record *, struct inode *);
 110extern int get_rock_ridge_filename(struct iso_directory_record *, char *, struct inode *);
 111extern int isofs_name_translate(struct iso_directory_record *, char *, struct inode *);
 112
 113int get_joliet_filename(struct iso_directory_record *, unsigned char *, struct inode *);
 114int get_acorn_filename(struct iso_directory_record *, char *, struct inode *);
 115
 116extern struct dentry *isofs_lookup(struct inode *, struct dentry *, struct nameidata *);
 117extern struct buffer_head *isofs_bread(struct inode *, sector_t);
 118extern int isofs_get_blocks(struct inode *, sector_t, struct buffer_head **, unsigned long);
 119
 120extern struct inode *isofs_iget(struct super_block *sb,
 121                                unsigned long block,
 122                                unsigned long offset);
 123
 124/* Because the inode number is no longer relevant to finding the
 125 * underlying meta-data for an inode, we are free to choose a more
 126 * convenient 32-bit number as the inode number.  The inode numbering
 127 * scheme was recommended by Sergey Vlasov and Eric Lammerts. */
 128static inline unsigned long isofs_get_ino(unsigned long block,
 129                                          unsigned long offset,
 130                                          unsigned long bufbits)
 131{
 132        return (block << (bufbits - 5)) | (offset >> 5);
 133}
 134
 135/* Every directory can have many redundant directory entries scattered
 136 * throughout the directory tree.  First there is the directory entry
 137 * with the name of the directory stored in the parent directory.
 138 * Then, there is the "." directory entry stored in the directory
 139 * itself.  Finally, there are possibly many ".." directory entries
 140 * stored in all the subdirectories.
 141 *
 142 * In order for the NFS get_parent() method to work and for the
 143 * general consistency of the dcache, we need to make sure the
 144 * "i_iget5_block" and "i_iget5_offset" all point to exactly one of
 145 * the many redundant entries for each directory.  We normalize the
 146 * block and offset by always making them point to the "."  directory.
 147 *
 148 * Notice that we do not use the entry for the directory with the name
 149 * that is located in the parent directory.  Even though choosing this
 150 * first directory is more natural, it is much easier to find the "."
 151 * entry in the NFS get_parent() method because it is implicitly
 152 * encoded in the "extent + ext_attr_length" fields of _all_ the
 153 * redundant entries for the directory.  Thus, it can always be
 154 * reached regardless of which directory entry you have in hand.
 155 *
 156 * This works because the "." entry is simply the first directory
 157 * record when you start reading the file that holds all the directory
 158 * records, and this file starts at "extent + ext_attr_length" blocks.
 159 * Because the "." entry is always the first entry listed in the
 160 * directories file, the normalized "offset" value is always 0.
 161 *
 162 * You should pass the directory entry in "de".  On return, "block"
 163 * and "offset" will hold normalized values.  Only directories are
 164 * affected making it safe to call even for non-directory file
 165 * types. */
 166static inline void
 167isofs_normalize_block_and_offset(struct iso_directory_record* de,
 168                                 unsigned long *block,
 169                                 unsigned long *offset)
 170{
 171        /* Only directories are normalized. */
 172        if (de->flags[0] & 2) {
 173                *offset = 0;
 174                *block = (unsigned long)isonum_733(de->extent)
 175                        + (unsigned long)isonum_711(de->ext_attr_length);
 176        }
 177}
 178
 179extern const struct inode_operations isofs_dir_inode_operations;
 180extern const struct file_operations isofs_dir_operations;
 181extern const struct address_space_operations isofs_symlink_aops;
 182extern const struct export_operations isofs_export_ops;
 183