blob: f20437c068a0bb344db90f2576e836445514eece [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/isofs/dir.c
3 *
4 * (C) 1992, 1993, 1994 Eric Youngdale Modified for ISO 9660 filesystem.
5 *
6 * (C) 1991 Linus Torvalds - minix filesystem
7 *
8 * Steve Beynon : Missing last directory entries fixed
9 * (stephen@askone.demon.co.uk) : 21st June 1996
Dave Jonesc3ed85a2007-07-15 23:40:03 -070010 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070011 * isofs directory handling functions
12 */
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090013#include <linux/gfp.h>
Al Viro94f2f712005-04-25 18:32:12 -070014#include "isofs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070015
Linus Torvalds1da177e2005-04-16 15:20:36 -070016int isofs_name_translate(struct iso_directory_record *de, char *new, struct inode *inode)
17{
18 char * old = de->name;
19 int len = de->name_len[0];
20 int i;
Dave Jonesc3ed85a2007-07-15 23:40:03 -070021
Linus Torvalds1da177e2005-04-16 15:20:36 -070022 for (i = 0; i < len; i++) {
23 unsigned char c = old[i];
24 if (!c)
25 break;
26
27 if (c >= 'A' && c <= 'Z')
28 c |= 0x20; /* lower case */
29
30 /* Drop trailing '.;1' (ISO 9660:1988 7.5.1 requires period) */
31 if (c == '.' && i == len - 3 && old[i + 1] == ';' && old[i + 2] == '1')
32 break;
33
34 /* Drop trailing ';1' */
35 if (c == ';' && i == len - 2 && old[i + 1] == '1')
36 break;
37
38 /* Convert remaining ';' to '.' */
39 /* Also '/' to '.' (broken Acorn-generated ISO9660 images) */
40 if (c == ';' || c == '/')
41 c = '.';
42
43 new[i] = c;
44 }
45 return i;
46}
47
48/* Acorn extensions written by Matthew Wilcox <willy@bofh.ai> 1998 */
Dave Jonesc3ed85a2007-07-15 23:40:03 -070049int get_acorn_filename(struct iso_directory_record *de,
50 char *retname, struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -070051{
52 int std;
Dave Jonesc3ed85a2007-07-15 23:40:03 -070053 unsigned char *chr;
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 int retnamlen = isofs_name_translate(de, retname, inode);
Dave Jonesc3ed85a2007-07-15 23:40:03 -070055
56 if (retnamlen == 0)
57 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 std = sizeof(struct iso_directory_record) + de->name_len[0];
Dave Jonesc3ed85a2007-07-15 23:40:03 -070059 if (std & 1)
60 std++;
61 if ((*((unsigned char *) de) - std) != 32)
62 return retnamlen;
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 chr = ((unsigned char *) de) + std;
Dave Jonesc3ed85a2007-07-15 23:40:03 -070064 if (strncmp(chr, "ARCHIMEDES", 10))
65 return retnamlen;
66 if ((*retname == '_') && ((chr[19] & 1) == 1))
67 *retname = '!';
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 if (((de->flags[0] & 2) == 0) && (chr[13] == 0xff)
Dave Jonesc3ed85a2007-07-15 23:40:03 -070069 && ((chr[12] & 0xf0) == 0xf0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 retname[retnamlen] = ',';
71 sprintf(retname+retnamlen+1, "%3.3x",
72 ((chr[12] & 0xf) << 8) | chr[11]);
73 retnamlen += 4;
74 }
75 return retnamlen;
76}
77
78/*
79 * This should _really_ be cleaned up some day..
80 */
81static int do_isofs_readdir(struct inode *inode, struct file *filp,
82 void *dirent, filldir_t filldir,
Dave Jonesc3ed85a2007-07-15 23:40:03 -070083 char *tmpname, struct iso_directory_record *tmpde)
Linus Torvalds1da177e2005-04-16 15:20:36 -070084{
85 unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
86 unsigned char bufbits = ISOFS_BUFFER_BITS(inode);
87 unsigned long block, offset, block_saved, offset_saved;
88 unsigned long inode_number = 0; /* Quiet GCC */
89 struct buffer_head *bh = NULL;
90 int len;
91 int map;
92 int first_de = 1;
93 char *p = NULL; /* Quiet GCC */
94 struct iso_directory_record *de;
95 struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb);
96
97 offset = filp->f_pos & (bufsize - 1);
98 block = filp->f_pos >> bufbits;
99
100 while (filp->f_pos < inode->i_size) {
101 int de_len;
102
103 if (!bh) {
104 bh = isofs_bread(inode, block);
105 if (!bh)
106 return 0;
107 }
108
109 de = (struct iso_directory_record *) (bh->b_data + offset);
110
111 de_len = *(unsigned char *) de;
112
Dave Jonesc3ed85a2007-07-15 23:40:03 -0700113 /*
114 * If the length byte is zero, we should move on to the next
115 * CDROM sector. If we are at the end of the directory, we
116 * kick out of the while loop.
117 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118
119 if (de_len == 0) {
120 brelse(bh);
121 bh = NULL;
122 filp->f_pos = (filp->f_pos + ISOFS_BLOCK_SIZE) & ~(ISOFS_BLOCK_SIZE - 1);
123 block = filp->f_pos >> bufbits;
124 offset = 0;
125 continue;
126 }
127
128 block_saved = block;
129 offset_saved = offset;
130 offset += de_len;
131
132 /* Make sure we have a full directory entry */
133 if (offset >= bufsize) {
134 int slop = bufsize - offset + de_len;
135 memcpy(tmpde, de, slop);
136 offset &= bufsize - 1;
137 block++;
138 brelse(bh);
139 bh = NULL;
140 if (offset) {
141 bh = isofs_bread(inode, block);
142 if (!bh)
143 return 0;
144 memcpy((void *) tmpde + slop, bh->b_data, offset);
145 }
146 de = tmpde;
147 }
Jan Kara2deb1ac2008-04-30 00:52:33 -0700148 /* Basic sanity check, whether name doesn't exceed dir entry */
149 if (de_len < de->name_len[0] +
150 sizeof(struct iso_directory_record)) {
151 printk(KERN_NOTICE "iso9660: Corrupted directory entry"
152 " in block %lu of inode %lu\n", block,
153 inode->i_ino);
154 return -EIO;
155 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156
157 if (first_de) {
158 isofs_normalize_block_and_offset(de,
Dave Jonesc3ed85a2007-07-15 23:40:03 -0700159 &block_saved,
160 &offset_saved);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 inode_number = isofs_get_ino(block_saved,
Dave Jonesc3ed85a2007-07-15 23:40:03 -0700162 offset_saved, bufbits);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163 }
164
165 if (de->flags[-sbi->s_high_sierra] & 0x80) {
166 first_de = 0;
167 filp->f_pos += de_len;
168 continue;
169 }
170 first_de = 1;
171
172 /* Handle the case of the '.' directory */
173 if (de->name_len[0] == 1 && de->name[0] == 0) {
174 if (filldir(dirent, ".", 1, filp->f_pos, inode->i_ino, DT_DIR) < 0)
175 break;
176 filp->f_pos += de_len;
177 continue;
178 }
179
180 len = 0;
181
182 /* Handle the case of the '..' directory */
183 if (de->name_len[0] == 1 && de->name[0] == 1) {
Josef "Jeff" Sipek24858222006-12-08 02:36:40 -0800184 inode_number = parent_ino(filp->f_path.dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 if (filldir(dirent, "..", 2, filp->f_pos, inode_number, DT_DIR) < 0)
186 break;
187 filp->f_pos += de_len;
188 continue;
189 }
190
191 /* Handle everything else. Do name translation if there
192 is no Rock Ridge NM field. */
Jeremy White9769f4e2005-06-21 17:16:53 -0700193
194 /*
195 * Do not report hidden files if so instructed, or associated
196 * files unless instructed to do so
197 */
Jan Kara5404ac82009-06-17 16:26:27 -0700198 if ((sbi->s_hide && (de->flags[-sbi->s_high_sierra] & 1)) ||
199 (!sbi->s_showassoc &&
Jeremy White9769f4e2005-06-21 17:16:53 -0700200 (de->flags[-sbi->s_high_sierra] & 4))) {
201 filp->f_pos += de_len;
202 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 }
204
205 map = 1;
206 if (sbi->s_rock) {
207 len = get_rock_ridge_filename(de, tmpname, inode);
208 if (len != 0) { /* may be -1 */
209 p = tmpname;
210 map = 0;
211 }
212 }
213 if (map) {
214#ifdef CONFIG_JOLIET
215 if (sbi->s_joliet_level) {
216 len = get_joliet_filename(de, tmpname, inode);
217 p = tmpname;
218 } else
219#endif
220 if (sbi->s_mapping == 'a') {
221 len = get_acorn_filename(de, tmpname, inode);
222 p = tmpname;
223 } else
224 if (sbi->s_mapping == 'n') {
225 len = isofs_name_translate(de, tmpname, inode);
226 p = tmpname;
227 } else {
228 p = de->name;
229 len = de->name_len[0];
230 }
231 }
232 if (len > 0) {
233 if (filldir(dirent, p, len, filp->f_pos, inode_number, DT_UNKNOWN) < 0)
234 break;
235 }
236 filp->f_pos += de_len;
237
238 continue;
239 }
Dave Jonesc3ed85a2007-07-15 23:40:03 -0700240 if (bh)
241 brelse(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 return 0;
243}
244
245/*
246 * Handle allocation of temporary space for name translation and
247 * handling split directory entries.. The real work is done by
248 * "do_isofs_readdir()".
249 */
250static int isofs_readdir(struct file *filp,
251 void *dirent, filldir_t filldir)
252{
253 int result;
Dave Jonesc3ed85a2007-07-15 23:40:03 -0700254 char *tmpname;
255 struct iso_directory_record *tmpde;
Josef "Jeff" Sipek24858222006-12-08 02:36:40 -0800256 struct inode *inode = filp->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257
258 tmpname = (char *)__get_free_page(GFP_KERNEL);
259 if (tmpname == NULL)
260 return -ENOMEM;
261
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 tmpde = (struct iso_directory_record *) (tmpname+1024);
263
264 result = do_isofs_readdir(inode, filp, dirent, filldir, tmpname, tmpde);
265
266 free_page((unsigned long) tmpname);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267 return result;
268}
Dave Jonesc3ed85a2007-07-15 23:40:03 -0700269
270const struct file_operations isofs_dir_operations =
271{
jan Blunckca572722010-05-26 14:44:53 -0700272 .llseek = generic_file_llseek,
Dave Jonesc3ed85a2007-07-15 23:40:03 -0700273 .read = generic_read_dir,
274 .readdir = isofs_readdir,
275};
276
277/*
278 * directories can handle most operations...
279 */
280const struct inode_operations isofs_dir_inode_operations =
281{
282 .lookup = isofs_lookup,
283};
284
285