LXR linux/fs/isofs/isofs.h

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