/* SPDX-License-Identifier: GPL-2.0 */ #include <linux/fs.h> #include <linux/buffer_head.h> #include <linux/exportfs.h> #include <linux/iso_fs.h> #include <asm/unaligned.h> enum isofs_file_format { isofs_file_normal = 0, isofs_file_sparse = 1, isofs_file_compressed = 2, }; /* * iso fs inode data in memory */ struct iso_inode_info { unsigned long i_iget5_block; unsigned long i_iget5_offset; unsigned int i_first_extent; unsigned char i_file_format; unsigned char i_format_parm[3]; unsigned long i_next_section_block; unsigned long i_next_section_offset; off_t i_section_size; struct inode vfs_inode; }; /* * iso9660 super-block data in memory */ struct isofs_sb_info { unsigned long s_ninodes; unsigned long s_nzones; unsigned long s_firstdatazone; unsigned long s_log_zone_size; unsigned long s_max_size; int s_rock_offset; /* offset of SUSP fields within SU area */ s32 s_sbsector; unsigned char s_joliet_level; unsigned char s_mapping; unsigned char s_check; unsigned char s_session; unsigned int s_high_sierra:1; unsigned int s_rock:2; unsigned int s_utf8:1; unsigned int s_cruft:1; /* Broken disks with high byte of length * containing junk */ unsigned int s_nocompress:1; unsigned int s_hide:1; unsigned int s_showassoc:1; unsigned int s_overriderockperm:1; unsigned int s_uid_set:1; unsigned int s_gid_set:1; umode_t s_fmode; umode_t s_dmode; kgid_t s_gid; kuid_t s_uid; struct nls_table *s_nls_iocharset; /* Native language support table */ }; #define ISOFS_INVALID_MODE ((umode_t) -1) static inline struct isofs_sb_info *ISOFS_SB(struct super_block *sb) { return sb->s_fs_info; } static inline struct iso_inode_info *ISOFS_I(struct inode *inode) { return container_of(inode, struct iso_inode_info, vfs_inode); } static inline int isonum_711(u8 *p) { return *p; } static inline int isonum_712(s8 *p) { return *p; } static inline unsigned int isonum_721(u8 *p) { return get_unaligned_le16(p); } static inline unsigned int isonum_722(u8 *p) { return get_unaligned_be16(p); } static inline unsigned int isonum_723(u8 *p) { /* Ignore bigendian datum due to broken mastering programs */ return get_unaligned_le16(p); } static inline unsigned int isonum_731(u8 *p) { return get_unaligned_le32(p); } static inline unsigned int isonum_732(u8 *p) { return get_unaligned_be32(p); } static inline unsigned int isonum_733(u8 *p) { /* Ignore bigendian datum due to broken mastering programs */ return get_unaligned_le32(p); } extern int iso_date(u8 *, int); struct inode; /* To make gcc happy */ extern int parse_rock_ridge_inode(struct iso_directory_record *, struct inode *, int relocated); extern int get_rock_ridge_filename(struct iso_directory_record *, char *, struct inode *); extern int isofs_name_translate(struct iso_directory_record *, char *, struct inode *); int get_joliet_filename(struct iso_directory_record *, unsigned char *, struct inode *); int get_acorn_filename(struct iso_directory_record *, char *, struct inode *); extern struct dentry *isofs_lookup(struct inode *, struct dentry *, unsigned int flags); extern struct buffer_head *isofs_bread(struct inode *, sector_t); extern int isofs_get_blocks(struct inode *, sector_t, struct buffer_head **, unsigned long); struct inode *__isofs_iget(struct super_block *sb, unsigned long block, unsigned long offset, int relocated); static inline struct inode *isofs_iget(struct super_block *sb, unsigned long block, unsigned long offset) { return __isofs_iget(sb, block, offset, 0); } static inline struct inode *isofs_iget_reloc(struct super_block *sb, unsigned long block, unsigned long offset) { return __isofs_iget(sb, block, offset, 1); } /* Because the inode number is no longer relevant to finding the * underlying meta-data for an inode, we are free to choose a more * convenient 32-bit number as the inode number. The inode numbering * scheme was recommended by Sergey Vlasov and Eric Lammerts. */ static inline unsigned long isofs_get_ino(unsigned long block, unsigned long offset, unsigned long bufbits) { return (block << (bufbits - 5)) | (offset >> 5); } /* Every directory can have many redundant directory entries scattered * throughout the directory tree. First there is the directory entry * with the name of the directory stored in the parent directory. * Then, there is the "." directory entry stored in the directory * itself. Finally, there are possibly many ".." directory entries * stored in all the subdirectories. * * In order for the NFS get_parent() method to work and for the * general consistency of the dcache, we need to make sure the * "i_iget5_block" and "i_iget5_offset" all point to exactly one of * the many redundant entries for each directory. We normalize the * block and offset by always making them point to the "." directory. * * Notice that we do not use the entry for the directory with the name * that is located in the parent directory. Even though choosing this * first directory is more natural, it is much easier to find the "." * entry in the NFS get_parent() method because it is implicitly * encoded in the "extent + ext_attr_length" fields of _all_ the * redundant entries for the directory. Thus, it can always be * reached regardless of which directory entry you have in hand. * * This works because the "." entry is simply the first directory * record when you start reading the file that holds all the directory * records, and this file starts at "extent + ext_attr_length" blocks. * Because the "." entry is always the first entry listed in the * directories file, the normalized "offset" value is always 0. * * You should pass the directory entry in "de". On return, "block" * and "offset" will hold normalized values. Only directories are * affected making it safe to call even for non-directory file * types. */ static inline void isofs_normalize_block_and_offset(struct iso_directory_record* de, unsigned long *block, unsigned long *offset) { /* Only directories are normalized. */ if (de->flags[0] & 2) { *offset = 0; *block = (unsigned long)isonum_733(de->extent) + (unsigned long)isonum_711(de->ext_attr_length); } } extern const struct inode_operations isofs_dir_inode_operations; extern const struct file_operations isofs_dir_operations; extern const struct address_space_operations isofs_symlink_aops; extern const struct export_operations isofs_export_ops;