Line data Source code
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 : };
59 :
60 : #define ISOFS_INVALID_MODE ((mode_t) -1)
61 :
62 : static inline struct isofs_sb_info *ISOFS_SB(struct super_block *sb)
63 : {
64 412 : return sb->s_fs_info;
65 : }
66 :
67 : static inline struct iso_inode_info *ISOFS_I(struct inode *inode)
68 : {
69 222 : return container_of(inode, struct iso_inode_info, vfs_inode);
70 : }
71 :
72 : static inline int isonum_711(char *p)
73 : {
74 24 : return *(u8 *)p;
75 : }
76 : static inline int isonum_712(char *p)
77 : {
78 : return *(s8 *)p;
79 : }
80 : static inline unsigned int isonum_721(char *p)
81 : {
82 : return get_unaligned_le16(p);
83 : }
84 : static inline unsigned int isonum_722(char *p)
85 : {
86 : return get_unaligned_be16(p);
87 : }
88 : static inline unsigned int isonum_723(char *p)
89 : {
90 26 : /* Ignore bigendian datum due to broken mastering programs */
91 78 : return get_unaligned_le16(p);
92 : }
93 : static inline unsigned int isonum_731(char *p)
94 : {
95 : return get_unaligned_le32(p);
96 : }
97 : static inline unsigned int isonum_732(char *p)
98 : {
99 : return get_unaligned_be32(p);
100 : }
101 : static inline unsigned int isonum_733(char *p)
102 : {
103 260 : /* Ignore bigendian datum due to broken mastering programs */
104 780 : return get_unaligned_le32(p);
105 : }
106 : extern int iso_date(char *, int);
107 :
108 : struct inode; /* To make gcc happy */
109 :
110 : extern int parse_rock_ridge_inode(struct iso_directory_record *, struct inode *);
111 : extern int get_rock_ridge_filename(struct iso_directory_record *, char *, struct inode *);
112 : extern int isofs_name_translate(struct iso_directory_record *, char *, struct inode *);
113 :
114 : int get_joliet_filename(struct iso_directory_record *, unsigned char *, struct inode *);
115 : int get_acorn_filename(struct iso_directory_record *, char *, struct inode *);
116 :
117 : extern struct dentry *isofs_lookup(struct inode *, struct dentry *, struct nameidata *);
118 : extern struct buffer_head *isofs_bread(struct inode *, sector_t);
119 : extern int isofs_get_blocks(struct inode *, sector_t, struct buffer_head **, unsigned long);
120 :
121 : extern struct inode *isofs_iget(struct super_block *sb,
122 : unsigned long block,
123 : unsigned long offset);
124 :
125 : /* Because the inode number is no longer relevant to finding the
126 : * underlying meta-data for an inode, we are free to choose a more
127 : * convenient 32-bit number as the inode number. The inode numbering
128 : * scheme was recommended by Sergey Vlasov and Eric Lammerts. */
129 : static inline unsigned long isofs_get_ino(unsigned long block,
130 : unsigned long offset,
131 : unsigned long bufbits)
132 : {
133 17 : return (block << (bufbits - 5)) | (offset >> 5);
134 : }
135 :
136 : /* Every directory can have many redundant directory entries scattered
137 : * throughout the directory tree. First there is the directory entry
138 : * with the name of the directory stored in the parent directory.
139 : * Then, there is the "." directory entry stored in the directory
140 : * itself. Finally, there are possibly many ".." directory entries
141 : * stored in all the subdirectories.
142 : *
143 : * In order for the NFS get_parent() method to work and for the
144 : * general consistency of the dcache, we need to make sure the
145 : * "i_iget5_block" and "i_iget5_offset" all point to exactly one of
146 : * the many redundant entries for each directory. We normalize the
147 : * block and offset by always making them point to the "." directory.
148 : *
149 : * Notice that we do not use the entry for the directory with the name
150 : * that is located in the parent directory. Even though choosing this
151 : * first directory is more natural, it is much easier to find the "."
152 : * entry in the NFS get_parent() method because it is implicitly
153 : * encoded in the "extent + ext_attr_length" fields of _all_ the
154 : * redundant entries for the directory. Thus, it can always be
155 : * reached regardless of which directory entry you have in hand.
156 : *
157 : * This works because the "." entry is simply the first directory
158 : * record when you start reading the file that holds all the directory
159 : * records, and this file starts at "extent + ext_attr_length" blocks.
160 : * Because the "." entry is always the first entry listed in the
161 : * directories file, the normalized "offset" value is always 0.
162 : *
163 : * You should pass the directory entry in "de". On return, "block"
164 : * and "offset" will hold normalized values. Only directories are
165 : * affected making it safe to call even for non-directory file
166 : * types. */
167 : static inline void
168 : isofs_normalize_block_and_offset(struct iso_directory_record* de,
169 : unsigned long *block,
170 : unsigned long *offset)
171 14 : {
172 14 : /* Only directories are normalized. */
173 28 : if (de->flags[0] & 2) {
174 14 : *offset = 0;
175 70 : *block = (unsigned long)isonum_733(de->extent)
176 : + (unsigned long)isonum_711(de->ext_attr_length);
177 : }
178 28 : }
179 :
180 1 : extern const struct inode_operations isofs_dir_inode_operations;
181 1 : extern const struct file_operations isofs_dir_operations;
182 1 : extern const struct address_space_operations isofs_symlink_aops;
183 1 : extern const struct export_operations isofs_export_ops;
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