tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
7enum 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 */
16struct 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 */
31struct 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
63static inline struct isofs_sb_info *ISOFS_SB(struct super_block *sb)
64{
65 return sb->s_fs_info;
66}
67
68static inline struct iso_inode_info *ISOFS_I(struct inode *inode)
69{
70 return container_of(inode, struct iso_inode_info, vfs_inode);
71}
72
73static inline int isonum_711(char *p)
74{
75 return *(u8 *)p;
76}
77static inline int isonum_712(char *p)
78{
79 return *(s8 *)p;
80}
81static inline unsigned int isonum_721(char *p)
82{
83 return get_unaligned_le16(p);
84}
85static inline unsigned int isonum_722(char *p)
86{
87 return get_unaligned_be16(p);
88}
89static inline unsigned int isonum_723(char *p)
90{
91 /* Ignore bigendian datum due to broken mastering programs */
92 return get_unaligned_le16(p);
93}
94static inline unsigned int isonum_731(char *p)
95{
96 return get_unaligned_le32(p);
97}
98static inline unsigned int isonum_732(char *p)
99{
100 return get_unaligned_be32(p);
101}
102static inline unsigned int isonum_733(char *p)
103{
104 /* Ignore bigendian datum due to broken mastering programs */
105 return get_unaligned_le32(p);
106}
107extern int iso_date(char *, int);
108
109struct inode; /* To make gcc happy */
110
111extern int parse_rock_ridge_inode(struct iso_directory_record *, struct inode *);
112extern int get_rock_ridge_filename(struct iso_directory_record *, char *, struct inode *);
113extern int isofs_name_translate(struct iso_directory_record *, char *, struct inode *);
114
115int get_joliet_filename(struct iso_directory_record *, unsigned char *, struct inode *);
116int get_acorn_filename(struct iso_directory_record *, char *, struct inode *);
117
118extern struct dentry *isofs_lookup(struct inode *, struct dentry *, struct nameidata *);
119extern struct buffer_head *isofs_bread(struct inode *, sector_t);
120extern int isofs_get_blocks(struct inode *, sector_t, struct buffer_head **, unsigned long);
121
122extern 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. */
130static 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. */
168static inline void
169isofs_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
181extern const struct inode_operations isofs_dir_inode_operations;
182extern const struct file_operations isofs_dir_operations;
183extern const struct address_space_operations isofs_symlink_aops;
184extern const struct export_operations isofs_export_ops;