isofs.h 6.0 KB

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