Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 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 |
| 10 | * |
| 11 | * isofs directory handling functions |
| 12 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <linux/smp_lock.h> |
Al Viro | 94f2f71 | 2005-04-25 18:32:12 -0700 | [diff] [blame] | 14 | #include "isofs.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | |
| 16 | static int isofs_readdir(struct file *, void *, filldir_t); |
| 17 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 18 | const struct file_operations isofs_dir_operations = |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | { |
| 20 | .read = generic_read_dir, |
| 21 | .readdir = isofs_readdir, |
| 22 | }; |
| 23 | |
| 24 | /* |
| 25 | * directories can handle most operations... |
| 26 | */ |
Arjan van de Ven | 92e1d5b | 2007-02-12 00:55:39 -0800 | [diff] [blame^] | 27 | const struct inode_operations isofs_dir_inode_operations = |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | { |
| 29 | .lookup = isofs_lookup, |
| 30 | }; |
| 31 | |
| 32 | int isofs_name_translate(struct iso_directory_record *de, char *new, struct inode *inode) |
| 33 | { |
| 34 | char * old = de->name; |
| 35 | int len = de->name_len[0]; |
| 36 | int i; |
| 37 | |
| 38 | for (i = 0; i < len; i++) { |
| 39 | unsigned char c = old[i]; |
| 40 | if (!c) |
| 41 | break; |
| 42 | |
| 43 | if (c >= 'A' && c <= 'Z') |
| 44 | c |= 0x20; /* lower case */ |
| 45 | |
| 46 | /* Drop trailing '.;1' (ISO 9660:1988 7.5.1 requires period) */ |
| 47 | if (c == '.' && i == len - 3 && old[i + 1] == ';' && old[i + 2] == '1') |
| 48 | break; |
| 49 | |
| 50 | /* Drop trailing ';1' */ |
| 51 | if (c == ';' && i == len - 2 && old[i + 1] == '1') |
| 52 | break; |
| 53 | |
| 54 | /* Convert remaining ';' to '.' */ |
| 55 | /* Also '/' to '.' (broken Acorn-generated ISO9660 images) */ |
| 56 | if (c == ';' || c == '/') |
| 57 | c = '.'; |
| 58 | |
| 59 | new[i] = c; |
| 60 | } |
| 61 | return i; |
| 62 | } |
| 63 | |
| 64 | /* Acorn extensions written by Matthew Wilcox <willy@bofh.ai> 1998 */ |
| 65 | int get_acorn_filename(struct iso_directory_record * de, |
| 66 | char * retname, struct inode * inode) |
| 67 | { |
| 68 | int std; |
| 69 | unsigned char * chr; |
| 70 | int retnamlen = isofs_name_translate(de, retname, inode); |
| 71 | if (retnamlen == 0) return 0; |
| 72 | std = sizeof(struct iso_directory_record) + de->name_len[0]; |
| 73 | if (std & 1) std++; |
| 74 | if ((*((unsigned char *) de) - std) != 32) return retnamlen; |
| 75 | chr = ((unsigned char *) de) + std; |
| 76 | if (strncmp(chr, "ARCHIMEDES", 10)) return retnamlen; |
| 77 | if ((*retname == '_') && ((chr[19] & 1) == 1)) *retname = '!'; |
| 78 | if (((de->flags[0] & 2) == 0) && (chr[13] == 0xff) |
| 79 | && ((chr[12] & 0xf0) == 0xf0)) |
| 80 | { |
| 81 | retname[retnamlen] = ','; |
| 82 | sprintf(retname+retnamlen+1, "%3.3x", |
| 83 | ((chr[12] & 0xf) << 8) | chr[11]); |
| 84 | retnamlen += 4; |
| 85 | } |
| 86 | return retnamlen; |
| 87 | } |
| 88 | |
| 89 | /* |
| 90 | * This should _really_ be cleaned up some day.. |
| 91 | */ |
| 92 | static int do_isofs_readdir(struct inode *inode, struct file *filp, |
| 93 | void *dirent, filldir_t filldir, |
| 94 | char * tmpname, struct iso_directory_record * tmpde) |
| 95 | { |
| 96 | unsigned long bufsize = ISOFS_BUFFER_SIZE(inode); |
| 97 | unsigned char bufbits = ISOFS_BUFFER_BITS(inode); |
| 98 | unsigned long block, offset, block_saved, offset_saved; |
| 99 | unsigned long inode_number = 0; /* Quiet GCC */ |
| 100 | struct buffer_head *bh = NULL; |
| 101 | int len; |
| 102 | int map; |
| 103 | int first_de = 1; |
| 104 | char *p = NULL; /* Quiet GCC */ |
| 105 | struct iso_directory_record *de; |
| 106 | struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb); |
| 107 | |
| 108 | offset = filp->f_pos & (bufsize - 1); |
| 109 | block = filp->f_pos >> bufbits; |
| 110 | |
| 111 | while (filp->f_pos < inode->i_size) { |
| 112 | int de_len; |
| 113 | |
| 114 | if (!bh) { |
| 115 | bh = isofs_bread(inode, block); |
| 116 | if (!bh) |
| 117 | return 0; |
| 118 | } |
| 119 | |
| 120 | de = (struct iso_directory_record *) (bh->b_data + offset); |
| 121 | |
| 122 | de_len = *(unsigned char *) de; |
| 123 | |
| 124 | /* If the length byte is zero, we should move on to the next |
| 125 | CDROM sector. If we are at the end of the directory, we |
| 126 | kick out of the while loop. */ |
| 127 | |
| 128 | if (de_len == 0) { |
| 129 | brelse(bh); |
| 130 | bh = NULL; |
| 131 | filp->f_pos = (filp->f_pos + ISOFS_BLOCK_SIZE) & ~(ISOFS_BLOCK_SIZE - 1); |
| 132 | block = filp->f_pos >> bufbits; |
| 133 | offset = 0; |
| 134 | continue; |
| 135 | } |
| 136 | |
| 137 | block_saved = block; |
| 138 | offset_saved = offset; |
| 139 | offset += de_len; |
| 140 | |
| 141 | /* Make sure we have a full directory entry */ |
| 142 | if (offset >= bufsize) { |
| 143 | int slop = bufsize - offset + de_len; |
| 144 | memcpy(tmpde, de, slop); |
| 145 | offset &= bufsize - 1; |
| 146 | block++; |
| 147 | brelse(bh); |
| 148 | bh = NULL; |
| 149 | if (offset) { |
| 150 | bh = isofs_bread(inode, block); |
| 151 | if (!bh) |
| 152 | return 0; |
| 153 | memcpy((void *) tmpde + slop, bh->b_data, offset); |
| 154 | } |
| 155 | de = tmpde; |
| 156 | } |
| 157 | |
| 158 | if (first_de) { |
| 159 | isofs_normalize_block_and_offset(de, |
| 160 | &block_saved, |
| 161 | &offset_saved); |
| 162 | inode_number = isofs_get_ino(block_saved, |
| 163 | offset_saved, |
| 164 | bufbits); |
| 165 | } |
| 166 | |
| 167 | if (de->flags[-sbi->s_high_sierra] & 0x80) { |
| 168 | first_de = 0; |
| 169 | filp->f_pos += de_len; |
| 170 | continue; |
| 171 | } |
| 172 | first_de = 1; |
| 173 | |
| 174 | /* Handle the case of the '.' directory */ |
| 175 | if (de->name_len[0] == 1 && de->name[0] == 0) { |
| 176 | if (filldir(dirent, ".", 1, filp->f_pos, inode->i_ino, DT_DIR) < 0) |
| 177 | break; |
| 178 | filp->f_pos += de_len; |
| 179 | continue; |
| 180 | } |
| 181 | |
| 182 | len = 0; |
| 183 | |
| 184 | /* Handle the case of the '..' directory */ |
| 185 | if (de->name_len[0] == 1 && de->name[0] == 1) { |
Josef "Jeff" Sipek | 2485822 | 2006-12-08 02:36:40 -0800 | [diff] [blame] | 186 | inode_number = parent_ino(filp->f_path.dentry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | if (filldir(dirent, "..", 2, filp->f_pos, inode_number, DT_DIR) < 0) |
| 188 | break; |
| 189 | filp->f_pos += de_len; |
| 190 | continue; |
| 191 | } |
| 192 | |
| 193 | /* Handle everything else. Do name translation if there |
| 194 | is no Rock Ridge NM field. */ |
Jeremy White | 9769f4e | 2005-06-21 17:16:53 -0700 | [diff] [blame] | 195 | |
| 196 | /* |
| 197 | * Do not report hidden files if so instructed, or associated |
| 198 | * files unless instructed to do so |
| 199 | */ |
| 200 | if ((sbi->s_hide == 'y' && |
| 201 | (de->flags[-sbi->s_high_sierra] & 1)) || |
| 202 | (sbi->s_showassoc =='n' && |
| 203 | (de->flags[-sbi->s_high_sierra] & 4))) { |
| 204 | filp->f_pos += de_len; |
| 205 | continue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | } |
| 207 | |
| 208 | map = 1; |
| 209 | if (sbi->s_rock) { |
| 210 | len = get_rock_ridge_filename(de, tmpname, inode); |
| 211 | if (len != 0) { /* may be -1 */ |
| 212 | p = tmpname; |
| 213 | map = 0; |
| 214 | } |
| 215 | } |
| 216 | if (map) { |
| 217 | #ifdef CONFIG_JOLIET |
| 218 | if (sbi->s_joliet_level) { |
| 219 | len = get_joliet_filename(de, tmpname, inode); |
| 220 | p = tmpname; |
| 221 | } else |
| 222 | #endif |
| 223 | if (sbi->s_mapping == 'a') { |
| 224 | len = get_acorn_filename(de, tmpname, inode); |
| 225 | p = tmpname; |
| 226 | } else |
| 227 | if (sbi->s_mapping == 'n') { |
| 228 | len = isofs_name_translate(de, tmpname, inode); |
| 229 | p = tmpname; |
| 230 | } else { |
| 231 | p = de->name; |
| 232 | len = de->name_len[0]; |
| 233 | } |
| 234 | } |
| 235 | if (len > 0) { |
| 236 | if (filldir(dirent, p, len, filp->f_pos, inode_number, DT_UNKNOWN) < 0) |
| 237 | break; |
| 238 | } |
| 239 | filp->f_pos += de_len; |
| 240 | |
| 241 | continue; |
| 242 | } |
| 243 | if (bh) brelse(bh); |
| 244 | return 0; |
| 245 | } |
| 246 | |
| 247 | /* |
| 248 | * Handle allocation of temporary space for name translation and |
| 249 | * handling split directory entries.. The real work is done by |
| 250 | * "do_isofs_readdir()". |
| 251 | */ |
| 252 | static int isofs_readdir(struct file *filp, |
| 253 | void *dirent, filldir_t filldir) |
| 254 | { |
| 255 | int result; |
| 256 | char * tmpname; |
| 257 | struct iso_directory_record * tmpde; |
Josef "Jeff" Sipek | 2485822 | 2006-12-08 02:36:40 -0800 | [diff] [blame] | 258 | struct inode *inode = filp->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 259 | |
| 260 | tmpname = (char *)__get_free_page(GFP_KERNEL); |
| 261 | if (tmpname == NULL) |
| 262 | return -ENOMEM; |
| 263 | |
| 264 | lock_kernel(); |
| 265 | tmpde = (struct iso_directory_record *) (tmpname+1024); |
| 266 | |
| 267 | result = do_isofs_readdir(inode, filp, dirent, filldir, tmpname, tmpde); |
| 268 | |
| 269 | free_page((unsigned long) tmpname); |
| 270 | unlock_kernel(); |
| 271 | return result; |
| 272 | } |