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
   7 enum 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  */
  16 struct 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  */
  31 struct 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         int           s_rock_offset; /* offset of SUSP fields within SU area */
  39         unsigned char s_joliet_level;
  40         unsigned char s_mapping;
  41         unsigned int  s_high_sierra:1;
  42         unsigned int  s_rock:2;
  43         unsigned int  s_utf8:1;
  44         unsigned int  s_cruft:1; /* Broken disks with high byte of length
  45                                   * containing junk */
  46         unsigned int  s_nocompress:1;
  47         unsigned int  s_hide:1;
  48         unsigned int  s_showassoc:1;
  49         unsigned int  s_overriderockperm:1;
  50         unsigned int  s_uid_set:1;
  51         unsigned int  s_gid_set:1;
  52
  53         mode_t s_fmode;
  54         mode_t s_dmode;
  55         gid_t s_gid;
  56         uid_t s_uid;
  57         struct nls_table *s_nls_iocharset; /* Native language support table */
  58         struct mutex s_mutex; /* replaces BKL, please remove if possible */
  59 };
  60
  61 #define ISOFS_INVALID_MODE ((mode_t) -1)
  62
  63 static inline struct isofs_sb_info *ISOFS_SB(struct super_block *sb)
  64 {
  65         return sb->s_fs_info;
  66 }
  67
  68 static inline struct iso_inode_info *ISOFS_I(struct inode *inode)
  69 {
  70         return container_of(inode, struct iso_inode_info, vfs_inode);
  71 }
  72
  73 static inline int isonum_711(char *p)
  74 {
  75         return *(u8 *)p;
  76 }
  77 static inline int isonum_712(char *p)
  78 {
  79         return *(s8 *)p;
  80 }
  81 static inline unsigned int isonum_721(char *p)
  82 {
  83         return get_unaligned_le16(p);
  84 }
  85 static inline unsigned int isonum_722(char *p)
  86 {
  87         return get_unaligned_be16(p);
  88 }
  89 static inline unsigned int isonum_723(char *p)
  90 {
  91         /* Ignore bigendian datum due to broken mastering programs */
  92         return get_unaligned_le16(p);
  93 }
  94 static inline unsigned int isonum_731(char *p)
  95 {
  96         return get_unaligned_le32(p);
  97 }
  98 static inline unsigned int isonum_732(char *p)
  99 {
 100         return get_unaligned_be32(p);
 101 }
 102 static inline unsigned int isonum_733(char *p)
 103 {
 104         /* Ignore bigendian datum due to broken mastering programs */
 105         return get_unaligned_le32(p);
 106 }
 107 extern int iso_date(char *, int);
 108
 109 struct inode;           /* To make gcc happy */
 110
 111 extern int parse_rock_ridge_inode(struct iso_directory_record *, struct inode *);
 112 extern int get_rock_ridge_filename(struct iso_directory_record *, char *, struct inode *);
 113 extern int isofs_name_translate(struct iso_directory_record *, char *, struct inode *);
 114
 115 int get_joliet_filename(struct iso_directory_record *, unsigned char *, struct inode *);
 116 int get_acorn_filename(struct iso_directory_record *, char *, struct inode *);
 117
 118 extern struct dentry *isofs_lookup(struct inode *, struct dentry *, struct nameidata *);
 119 extern struct buffer_head *isofs_bread(struct inode *, sector_t);
 120 extern int isofs_get_blocks(struct inode *, sector_t, struct buffer_head **, unsigned long);
 121
 122 extern struct inode *isofs_iget(struct super_block *sb,
 123                                 unsigned long block,
 124                                 unsigned long offset);
 125
 126 /* Because the inode number is no longer relevant to finding the
 127  * underlying meta-data for an inode, we are free to choose a more
 128  * convenient 32-bit number as the inode number.  The inode numbering
 129  * scheme was recommended by Sergey Vlasov and Eric Lammerts. */
 130 static inline unsigned long isofs_get_ino(unsigned long block,
 131                                           unsigned long offset,
 132                                           unsigned long bufbits)
 133 {
 134         return (block << (bufbits - 5)) | (offset >> 5);
 135 }
 136
 137 /* Every directory can have many redundant directory entries scattered
 138  * throughout the directory tree.  First there is the directory entry
 139  * with the name of the directory stored in the parent directory.
 140  * Then, there is the "." directory entry stored in the directory
 141  * itself.  Finally, there are possibly many ".." directory entries
 142  * stored in all the subdirectories.
 143  *
 144  * In order for the NFS get_parent() method to work and for the
 145  * general consistency of the dcache, we need to make sure the
 146  * "i_iget5_block" and "i_iget5_offset" all point to exactly one of
 147  * the many redundant entries for each directory.  We normalize the
 148  * block and offset by always making them point to the "."  directory.
 149  *
 150  * Notice that we do not use the entry for the directory with the name
 151  * that is located in the parent directory.  Even though choosing this
 152  * first directory is more natural, it is much easier to find the "."
 153  * entry in the NFS get_parent() method because it is implicitly
 154  * encoded in the "extent + ext_attr_length" fields of _all_ the
 155  * redundant entries for the directory.  Thus, it can always be
 156  * reached regardless of which directory entry you have in hand.
 157  *
 158  * This works because the "." entry is simply the first directory
 159  * record when you start reading the file that holds all the directory
 160  * records, and this file starts at "extent + ext_attr_length" blocks.
 161  * Because the "." entry is always the first entry listed in the
 162  * directories file, the normalized "offset" value is always 0.
 163  *
 164  * You should pass the directory entry in "de".  On return, "block"
 165  * and "offset" will hold normalized values.  Only directories are
 166  * affected making it safe to call even for non-directory file
 167  * types. */
 168 static inline void
 169 isofs_normalize_block_and_offset(struct iso_directory_record* de,
 170                                  unsigned long *block,
 171                                  unsigned long *offset)
 172 {
 173         /* Only directories are normalized. */
 174         if (de->flags[0] & 2) {
 175                 *offset = 0;
 176                 *block = (unsigned long)isonum_733(de->extent)
 177                         + (unsigned long)isonum_711(de->ext_attr_length);
 178         }
 179 }
 180
 181 extern const struct inode_operations isofs_dir_inode_operations;
 182 extern const struct file_operations isofs_dir_operations;
 183 extern const struct address_space_operations isofs_symlink_aops;
 184 extern const struct export_operations isofs_export_ops;