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Linux/fs/isofs/inode.c

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  1 // SPDX-License-Identifier: GPL-2.0-only
  2 /*
  3  *  linux/fs/isofs/inode.c
  4  *
  5  *  (C) 1991  Linus Torvalds - minix filesystem
  6  *      1992, 1993, 1994  Eric Youngdale Modified for ISO 9660 filesystem.
  7  *      1994  Eberhard Mönkeberg - multi session handling.
  8  *      1995  Mark Dobie - allow mounting of some weird VideoCDs and PhotoCDs.
  9  *      1997  Gordon Chaffee - Joliet CDs
 10  *      1998  Eric Lammerts - ISO 9660 Level 3
 11  *      2004  Paul Serice - Inode Support pushed out from 4GB to 128GB
 12  *      2004  Paul Serice - NFS Export Operations
 13  */
 14 
 15 #include <linux/init.h>
 16 #include <linux/module.h>
 17 
 18 #include <linux/slab.h>
 19 #include <linux/cred.h>
 20 #include <linux/nls.h>
 21 #include <linux/ctype.h>
 22 #include <linux/statfs.h>
 23 #include <linux/cdrom.h>
 24 #include <linux/parser.h>
 25 #include <linux/mpage.h>
 26 #include <linux/user_namespace.h>
 27 #include <linux/seq_file.h>
 28 #include <linux/blkdev.h>
 29 
 30 #include "isofs.h"
 31 #include "zisofs.h"
 32 
 33 /* max tz offset is 13 hours */
 34 #define MAX_TZ_OFFSET (52*15*60)
 35 
 36 #define BEQUIET
 37 
 38 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
 39 static int isofs_dentry_cmpi(const struct dentry *dentry,
 40                 unsigned int len, const char *str, const struct qstr *name);
 41 
 42 #ifdef CONFIG_JOLIET
 43 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
 44 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
 45 static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
 46                 unsigned int len, const char *str, const struct qstr *name);
 47 static int isofs_dentry_cmp_ms(const struct dentry *dentry,
 48                 unsigned int len, const char *str, const struct qstr *name);
 49 #endif
 50 
 51 static void isofs_put_super(struct super_block *sb)
 52 {
 53         struct isofs_sb_info *sbi = ISOFS_SB(sb);
 54 
 55 #ifdef CONFIG_JOLIET
 56         unload_nls(sbi->s_nls_iocharset);
 57 #endif
 58 
 59         kfree(sbi);
 60         sb->s_fs_info = NULL;
 61         return;
 62 }
 63 
 64 static int isofs_read_inode(struct inode *, int relocated);
 65 static int isofs_statfs (struct dentry *, struct kstatfs *);
 66 static int isofs_show_options(struct seq_file *, struct dentry *);
 67 
 68 static struct kmem_cache *isofs_inode_cachep;
 69 
 70 static struct inode *isofs_alloc_inode(struct super_block *sb)
 71 {
 72         struct iso_inode_info *ei;
 73         ei = kmem_cache_alloc(isofs_inode_cachep, GFP_KERNEL);
 74         if (!ei)
 75                 return NULL;
 76         return &ei->vfs_inode;
 77 }
 78 
 79 static void isofs_free_inode(struct inode *inode)
 80 {
 81         kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
 82 }
 83 
 84 static void init_once(void *foo)
 85 {
 86         struct iso_inode_info *ei = foo;
 87 
 88         inode_init_once(&ei->vfs_inode);
 89 }
 90 
 91 static int __init init_inodecache(void)
 92 {
 93         isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
 94                                         sizeof(struct iso_inode_info),
 95                                         0, (SLAB_RECLAIM_ACCOUNT|
 96                                         SLAB_MEM_SPREAD|SLAB_ACCOUNT),
 97                                         init_once);
 98         if (!isofs_inode_cachep)
 99                 return -ENOMEM;
100         return 0;
101 }
102 
103 static void destroy_inodecache(void)
104 {
105         /*
106          * Make sure all delayed rcu free inodes are flushed before we
107          * destroy cache.
108          */
109         rcu_barrier();
110         kmem_cache_destroy(isofs_inode_cachep);
111 }
112 
113 static int isofs_remount(struct super_block *sb, int *flags, char *data)
114 {
115         sync_filesystem(sb);
116         if (!(*flags & SB_RDONLY))
117                 return -EROFS;
118         return 0;
119 }
120 
121 static const struct super_operations isofs_sops = {
122         .alloc_inode    = isofs_alloc_inode,
123         .free_inode     = isofs_free_inode,
124         .put_super      = isofs_put_super,
125         .statfs         = isofs_statfs,
126         .remount_fs     = isofs_remount,
127         .show_options   = isofs_show_options,
128 };
129 
130 
131 static const struct dentry_operations isofs_dentry_ops[] = {
132         {
133                 .d_hash         = isofs_hashi,
134                 .d_compare      = isofs_dentry_cmpi,
135         },
136 #ifdef CONFIG_JOLIET
137         {
138                 .d_hash         = isofs_hash_ms,
139                 .d_compare      = isofs_dentry_cmp_ms,
140         },
141         {
142                 .d_hash         = isofs_hashi_ms,
143                 .d_compare      = isofs_dentry_cmpi_ms,
144         },
145 #endif
146 };
147 
148 struct iso9660_options{
149         unsigned int rock:1;
150         unsigned int joliet:1;
151         unsigned int cruft:1;
152         unsigned int hide:1;
153         unsigned int showassoc:1;
154         unsigned int nocompress:1;
155         unsigned int overriderockperm:1;
156         unsigned int uid_set:1;
157         unsigned int gid_set:1;
158         unsigned char map;
159         unsigned char check;
160         unsigned int blocksize;
161         umode_t fmode;
162         umode_t dmode;
163         kgid_t gid;
164         kuid_t uid;
165         char *iocharset;
166         /* LVE */
167         s32 session;
168         s32 sbsector;
169 };
170 
171 /*
172  * Compute the hash for the isofs name corresponding to the dentry.
173  */
174 static int
175 isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
176 {
177         const char *name;
178         int len;
179         char c;
180         unsigned long hash;
181 
182         len = qstr->len;
183         name = qstr->name;
184         if (ms) {
185                 while (len && name[len-1] == '.')
186                         len--;
187         }
188 
189         hash = init_name_hash(dentry);
190         while (len--) {
191                 c = tolower(*name++);
192                 hash = partial_name_hash(c, hash);
193         }
194         qstr->hash = end_name_hash(hash);
195 
196         return 0;
197 }
198 
199 /*
200  * Compare of two isofs names.
201  */
202 static int isofs_dentry_cmp_common(
203                 unsigned int len, const char *str,
204                 const struct qstr *name, int ms, int ci)
205 {
206         int alen, blen;
207 
208         /* A filename cannot end in '.' or we treat it like it has none */
209         alen = name->len;
210         blen = len;
211         if (ms) {
212                 while (alen && name->name[alen-1] == '.')
213                         alen--;
214                 while (blen && str[blen-1] == '.')
215                         blen--;
216         }
217         if (alen == blen) {
218                 if (ci) {
219                         if (strncasecmp(name->name, str, alen) == 0)
220                                 return 0;
221                 } else {
222                         if (strncmp(name->name, str, alen) == 0)
223                                 return 0;
224                 }
225         }
226         return 1;
227 }
228 
229 static int
230 isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
231 {
232         return isofs_hashi_common(dentry, qstr, 0);
233 }
234 
235 static int
236 isofs_dentry_cmpi(const struct dentry *dentry,
237                 unsigned int len, const char *str, const struct qstr *name)
238 {
239         return isofs_dentry_cmp_common(len, str, name, 0, 1);
240 }
241 
242 #ifdef CONFIG_JOLIET
243 /*
244  * Compute the hash for the isofs name corresponding to the dentry.
245  */
246 static int
247 isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
248 {
249         const char *name;
250         int len;
251 
252         len = qstr->len;
253         name = qstr->name;
254         if (ms) {
255                 while (len && name[len-1] == '.')
256                         len--;
257         }
258 
259         qstr->hash = full_name_hash(dentry, name, len);
260 
261         return 0;
262 }
263 
264 static int
265 isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
266 {
267         return isofs_hash_common(dentry, qstr, 1);
268 }
269 
270 static int
271 isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
272 {
273         return isofs_hashi_common(dentry, qstr, 1);
274 }
275 
276 static int
277 isofs_dentry_cmp_ms(const struct dentry *dentry,
278                 unsigned int len, const char *str, const struct qstr *name)
279 {
280         return isofs_dentry_cmp_common(len, str, name, 1, 0);
281 }
282 
283 static int
284 isofs_dentry_cmpi_ms(const struct dentry *dentry,
285                 unsigned int len, const char *str, const struct qstr *name)
286 {
287         return isofs_dentry_cmp_common(len, str, name, 1, 1);
288 }
289 #endif
290 
291 enum {
292         Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
293         Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
294         Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
295         Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
296 };
297 
298 static const match_table_t tokens = {
299         {Opt_norock, "norock"},
300         {Opt_nojoliet, "nojoliet"},
301         {Opt_unhide, "unhide"},
302         {Opt_hide, "hide"},
303         {Opt_showassoc, "showassoc"},
304         {Opt_cruft, "cruft"},
305         {Opt_utf8, "utf8"},
306         {Opt_iocharset, "iocharset=%s"},
307         {Opt_map_a, "map=acorn"},
308         {Opt_map_a, "map=a"},
309         {Opt_map_n, "map=normal"},
310         {Opt_map_n, "map=n"},
311         {Opt_map_o, "map=off"},
312         {Opt_map_o, "map=o"},
313         {Opt_session, "session=%u"},
314         {Opt_sb, "sbsector=%u"},
315         {Opt_check_r, "check=relaxed"},
316         {Opt_check_r, "check=r"},
317         {Opt_check_s, "check=strict"},
318         {Opt_check_s, "check=s"},
319         {Opt_uid, "uid=%u"},
320         {Opt_gid, "gid=%u"},
321         {Opt_mode, "mode=%u"},
322         {Opt_dmode, "dmode=%u"},
323         {Opt_overriderockperm, "overriderockperm"},
324         {Opt_block, "block=%u"},
325         {Opt_ignore, "conv=binary"},
326         {Opt_ignore, "conv=b"},
327         {Opt_ignore, "conv=text"},
328         {Opt_ignore, "conv=t"},
329         {Opt_ignore, "conv=mtext"},
330         {Opt_ignore, "conv=m"},
331         {Opt_ignore, "conv=auto"},
332         {Opt_ignore, "conv=a"},
333         {Opt_nocompress, "nocompress"},
334         {Opt_err, NULL}
335 };
336 
337 static int parse_options(char *options, struct iso9660_options *popt)
338 {
339         char *p;
340         int option;
341         unsigned int uv;
342 
343         popt->map = 'n';
344         popt->rock = 1;
345         popt->joliet = 1;
346         popt->cruft = 0;
347         popt->hide = 0;
348         popt->showassoc = 0;
349         popt->check = 'u';              /* unset */
350         popt->nocompress = 0;
351         popt->blocksize = 1024;
352         popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
353         popt->uid_set = 0;
354         popt->gid_set = 0;
355         popt->gid = GLOBAL_ROOT_GID;
356         popt->uid = GLOBAL_ROOT_UID;
357         popt->iocharset = NULL;
358         popt->overriderockperm = 0;
359         popt->session=-1;
360         popt->sbsector=-1;
361         if (!options)
362                 return 1;
363 
364         while ((p = strsep(&options, ",")) != NULL) {
365                 int token;
366                 substring_t args[MAX_OPT_ARGS];
367                 unsigned n;
368 
369                 if (!*p)
370                         continue;
371 
372                 token = match_token(p, tokens, args);
373                 switch (token) {
374                 case Opt_norock:
375                         popt->rock = 0;
376                         break;
377                 case Opt_nojoliet:
378                         popt->joliet = 0;
379                         break;
380                 case Opt_hide:
381                         popt->hide = 1;
382                         break;
383                 case Opt_unhide:
384                 case Opt_showassoc:
385                         popt->showassoc = 1;
386                         break;
387                 case Opt_cruft:
388                         popt->cruft = 1;
389                         break;
390 #ifdef CONFIG_JOLIET
391                 case Opt_utf8:
392                         kfree(popt->iocharset);
393                         popt->iocharset = kstrdup("utf8", GFP_KERNEL);
394                         if (!popt->iocharset)
395                                 return 0;
396                         break;
397                 case Opt_iocharset:
398                         kfree(popt->iocharset);
399                         popt->iocharset = match_strdup(&args[0]);
400                         if (!popt->iocharset)
401                                 return 0;
402                         break;
403 #endif
404                 case Opt_map_a:
405                         popt->map = 'a';
406                         break;
407                 case Opt_map_o:
408                         popt->map = 'o';
409                         break;
410                 case Opt_map_n:
411                         popt->map = 'n';
412                         break;
413                 case Opt_session:
414                         if (match_int(&args[0], &option))
415                                 return 0;
416                         n = option;
417                         /*
418                          * Track numbers are supposed to be in range 1-99, the
419                          * mount option starts indexing at 0.
420                          */
421                         if (n >= 99)
422                                 return 0;
423                         popt->session = n + 1;
424                         break;
425                 case Opt_sb:
426                         if (match_int(&args[0], &option))
427                                 return 0;
428                         popt->sbsector = option;
429                         break;
430                 case Opt_check_r:
431                         popt->check = 'r';
432                         break;
433                 case Opt_check_s:
434                         popt->check = 's';
435                         break;
436                 case Opt_ignore:
437                         break;
438                 case Opt_uid:
439                         if (match_uint(&args[0], &uv))
440                                 return 0;
441                         popt->uid = make_kuid(current_user_ns(), uv);
442                         if (!uid_valid(popt->uid))
443                                 return 0;
444                         popt->uid_set = 1;
445                         break;
446                 case Opt_gid:
447                         if (match_uint(&args[0], &uv))
448                                 return 0;
449                         popt->gid = make_kgid(current_user_ns(), uv);
450                         if (!gid_valid(popt->gid))
451                                 return 0;
452                         popt->gid_set = 1;
453                         break;
454                 case Opt_mode:
455                         if (match_int(&args[0], &option))
456                                 return 0;
457                         popt->fmode = option;
458                         break;
459                 case Opt_dmode:
460                         if (match_int(&args[0], &option))
461                                 return 0;
462                         popt->dmode = option;
463                         break;
464                 case Opt_overriderockperm:
465                         popt->overriderockperm = 1;
466                         break;
467                 case Opt_block:
468                         if (match_int(&args[0], &option))
469                                 return 0;
470                         n = option;
471                         if (n != 512 && n != 1024 && n != 2048)
472                                 return 0;
473                         popt->blocksize = n;
474                         break;
475                 case Opt_nocompress:
476                         popt->nocompress = 1;
477                         break;
478                 default:
479                         return 0;
480                 }
481         }
482         return 1;
483 }
484 
485 /*
486  * Display the mount options in /proc/mounts.
487  */
488 static int isofs_show_options(struct seq_file *m, struct dentry *root)
489 {
490         struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
491 
492         if (!sbi->s_rock)               seq_puts(m, ",norock");
493         else if (!sbi->s_joliet_level)  seq_puts(m, ",nojoliet");
494         if (sbi->s_cruft)               seq_puts(m, ",cruft");
495         if (sbi->s_hide)                seq_puts(m, ",hide");
496         if (sbi->s_nocompress)          seq_puts(m, ",nocompress");
497         if (sbi->s_overriderockperm)    seq_puts(m, ",overriderockperm");
498         if (sbi->s_showassoc)           seq_puts(m, ",showassoc");
499 
500         if (sbi->s_check)               seq_printf(m, ",check=%c", sbi->s_check);
501         if (sbi->s_mapping)             seq_printf(m, ",map=%c", sbi->s_mapping);
502         if (sbi->s_session != 255)      seq_printf(m, ",session=%u", sbi->s_session - 1);
503         if (sbi->s_sbsector != -1)      seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
504 
505         if (root->d_sb->s_blocksize != 1024)
506                 seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
507 
508         if (sbi->s_uid_set)
509                 seq_printf(m, ",uid=%u",
510                            from_kuid_munged(&init_user_ns, sbi->s_uid));
511         if (sbi->s_gid_set)
512                 seq_printf(m, ",gid=%u",
513                            from_kgid_munged(&init_user_ns, sbi->s_gid));
514 
515         if (sbi->s_dmode != ISOFS_INVALID_MODE)
516                 seq_printf(m, ",dmode=%o", sbi->s_dmode);
517         if (sbi->s_fmode != ISOFS_INVALID_MODE)
518                 seq_printf(m, ",fmode=%o", sbi->s_fmode);
519 
520 #ifdef CONFIG_JOLIET
521         if (sbi->s_nls_iocharset)
522                 seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
523         else
524                 seq_puts(m, ",iocharset=utf8");
525 #endif
526         return 0;
527 }
528 
529 /*
530  * look if the driver can tell the multi session redirection value
531  *
532  * don't change this if you don't know what you do, please!
533  * Multisession is legal only with XA disks.
534  * A non-XA disk with more than one volume descriptor may do it right, but
535  * usually is written in a nowhere standardized "multi-partition" manner.
536  * Multisession uses absolute addressing (solely the first frame of the whole
537  * track is #0), multi-partition uses relative addressing (each first frame of
538  * each track is #0), and a track is not a session.
539  *
540  * A broken CDwriter software or drive firmware does not set new standards,
541  * at least not if conflicting with the existing ones.
542  *
543  * emoenke@gwdg.de
544  */
545 #define WE_OBEY_THE_WRITTEN_STANDARDS 1
546 
547 static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
548 {
549         struct cdrom_device_info *cdi = disk_to_cdi(sb->s_bdev->bd_disk);
550         unsigned int vol_desc_start = 0;
551 
552         if (session > 0) {
553                 struct cdrom_tocentry te;
554 
555                 if (!cdi)
556                         return 0;
557 
558                 te.cdte_track = session;
559                 te.cdte_format = CDROM_LBA;
560                 if (cdrom_read_tocentry(cdi, &te) == 0) {
561                         printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
562                                 session, te.cdte_addr.lba,
563                                 te.cdte_ctrl & CDROM_DATA_TRACK);
564                         if ((te.cdte_ctrl & CDROM_DATA_TRACK) == 4)
565                                 return te.cdte_addr.lba;
566                 }
567 
568                 printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
569         }
570 
571         if (cdi) {
572                 struct cdrom_multisession ms_info;
573 
574                 ms_info.addr_format = CDROM_LBA;
575                 if (cdrom_multisession(cdi, &ms_info) == 0) {
576 #if WE_OBEY_THE_WRITTEN_STANDARDS
577                         /* necessary for a valid ms_info.addr */
578                         if (ms_info.xa_flag)
579 #endif
580                                 vol_desc_start = ms_info.addr.lba;
581                 }
582         }
583 
584         return vol_desc_start;
585 }
586 
587 /*
588  * Check if root directory is empty (has less than 3 files).
589  *
590  * Used to detect broken CDs where ISO root directory is empty but Joliet root
591  * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
592  * (and Joliet used instead) or else no files would be visible.
593  */
594 static bool rootdir_empty(struct super_block *sb, unsigned long block)
595 {
596         int offset = 0, files = 0, de_len;
597         struct iso_directory_record *de;
598         struct buffer_head *bh;
599 
600         bh = sb_bread(sb, block);
601         if (!bh)
602                 return true;
603         while (files < 3) {
604                 de = (struct iso_directory_record *) (bh->b_data + offset);
605                 de_len = *(unsigned char *) de;
606                 if (de_len == 0)
607                         break;
608                 files++;
609                 offset += de_len;
610         }
611         brelse(bh);
612         return files < 3;
613 }
614 
615 /*
616  * Initialize the superblock and read the root inode.
617  */
618 static int isofs_fill_super(struct super_block *s, void *data, int silent)
619 {
620         struct buffer_head *bh = NULL, *pri_bh = NULL;
621         struct hs_primary_descriptor *h_pri = NULL;
622         struct iso_primary_descriptor *pri = NULL;
623         struct iso_supplementary_descriptor *sec = NULL;
624         struct iso_directory_record *rootp;
625         struct inode *inode;
626         struct iso9660_options opt;
627         struct isofs_sb_info *sbi;
628         unsigned long first_data_zone;
629         int joliet_level = 0;
630         int iso_blknum, block;
631         int orig_zonesize;
632         int table, error = -EINVAL;
633         unsigned int vol_desc_start;
634 
635         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
636         if (!sbi)
637                 return -ENOMEM;
638         s->s_fs_info = sbi;
639 
640         if (!parse_options((char *)data, &opt))
641                 goto out_freesbi;
642 
643         /*
644          * First of all, get the hardware blocksize for this device.
645          * If we don't know what it is, or the hardware blocksize is
646          * larger than the blocksize the user specified, then use
647          * that value.
648          */
649         /*
650          * What if bugger tells us to go beyond page size?
651          */
652         if (bdev_logical_block_size(s->s_bdev) > 2048) {
653                 printk(KERN_WARNING
654                        "ISOFS: unsupported/invalid hardware sector size %d\n",
655                         bdev_logical_block_size(s->s_bdev));
656                 goto out_freesbi;
657         }
658         opt.blocksize = sb_min_blocksize(s, opt.blocksize);
659 
660         sbi->s_high_sierra = 0; /* default is iso9660 */
661         sbi->s_session = opt.session;
662         sbi->s_sbsector = opt.sbsector;
663 
664         vol_desc_start = (opt.sbsector != -1) ?
665                 opt.sbsector : isofs_get_last_session(s,opt.session);
666 
667         for (iso_blknum = vol_desc_start+16;
668                 iso_blknum < vol_desc_start+100; iso_blknum++) {
669                 struct hs_volume_descriptor *hdp;
670                 struct iso_volume_descriptor  *vdp;
671 
672                 block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
673                 if (!(bh = sb_bread(s, block)))
674                         goto out_no_read;
675 
676                 vdp = (struct iso_volume_descriptor *)bh->b_data;
677                 hdp = (struct hs_volume_descriptor *)bh->b_data;
678 
679                 /*
680                  * Due to the overlapping physical location of the descriptors,
681                  * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
682                  * proper identification in this case, we first check for ISO.
683                  */
684                 if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
685                         if (isonum_711(vdp->type) == ISO_VD_END)
686                                 break;
687                         if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
688                                 if (!pri) {
689                                         pri = (struct iso_primary_descriptor *)vdp;
690                                         /* Save the buffer in case we need it ... */
691                                         pri_bh = bh;
692                                         bh = NULL;
693                                 }
694                         }
695 #ifdef CONFIG_JOLIET
696                         else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
697                                 sec = (struct iso_supplementary_descriptor *)vdp;
698                                 if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
699                                         if (opt.joliet) {
700                                                 if (sec->escape[2] == 0x40)
701                                                         joliet_level = 1;
702                                                 else if (sec->escape[2] == 0x43)
703                                                         joliet_level = 2;
704                                                 else if (sec->escape[2] == 0x45)
705                                                         joliet_level = 3;
706 
707                                                 printk(KERN_DEBUG "ISO 9660 Extensions: "
708                                                         "Microsoft Joliet Level %d\n",
709                                                         joliet_level);
710                                         }
711                                         goto root_found;
712                                 } else {
713                                 /* Unknown supplementary volume descriptor */
714                                 sec = NULL;
715                                 }
716                         }
717 #endif
718                 } else {
719                         if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
720                                 if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
721                                         goto out_freebh;
722 
723                                 sbi->s_high_sierra = 1;
724                                 opt.rock = 0;
725                                 h_pri = (struct hs_primary_descriptor *)vdp;
726                                 goto root_found;
727                         }
728                 }
729 
730                 /* Just skip any volume descriptors we don't recognize */
731 
732                 brelse(bh);
733                 bh = NULL;
734         }
735         /*
736          * If we fall through, either no volume descriptor was found,
737          * or else we passed a primary descriptor looking for others.
738          */
739         if (!pri)
740                 goto out_unknown_format;
741         brelse(bh);
742         bh = pri_bh;
743         pri_bh = NULL;
744 
745 root_found:
746         /* We don't support read-write mounts */
747         if (!sb_rdonly(s)) {
748                 error = -EACCES;
749                 goto out_freebh;
750         }
751 
752         if (joliet_level && (!pri || !opt.rock)) {
753                 /* This is the case of Joliet with the norock mount flag.
754                  * A disc with both Joliet and Rock Ridge is handled later
755                  */
756                 pri = (struct iso_primary_descriptor *) sec;
757         }
758 
759         if(sbi->s_high_sierra){
760                 rootp = (struct iso_directory_record *) h_pri->root_directory_record;
761                 sbi->s_nzones = isonum_733(h_pri->volume_space_size);
762                 sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
763                 sbi->s_max_size = isonum_733(h_pri->volume_space_size);
764         } else {
765                 if (!pri)
766                         goto out_freebh;
767                 rootp = (struct iso_directory_record *) pri->root_directory_record;
768                 sbi->s_nzones = isonum_733(pri->volume_space_size);
769                 sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
770                 sbi->s_max_size = isonum_733(pri->volume_space_size);
771         }
772 
773         sbi->s_ninodes = 0; /* No way to figure this out easily */
774 
775         orig_zonesize = sbi->s_log_zone_size;
776         /*
777          * If the zone size is smaller than the hardware sector size,
778          * this is a fatal error.  This would occur if the disc drive
779          * had sectors that were 2048 bytes, but the filesystem had
780          * blocks that were 512 bytes (which should only very rarely
781          * happen.)
782          */
783         if (orig_zonesize < opt.blocksize)
784                 goto out_bad_size;
785 
786         /* RDE: convert log zone size to bit shift */
787         switch (sbi->s_log_zone_size) {
788         case  512: sbi->s_log_zone_size =  9; break;
789         case 1024: sbi->s_log_zone_size = 10; break;
790         case 2048: sbi->s_log_zone_size = 11; break;
791 
792         default:
793                 goto out_bad_zone_size;
794         }
795 
796         s->s_magic = ISOFS_SUPER_MAGIC;
797 
798         /*
799          * With multi-extent files, file size is only limited by the maximum
800          * size of a file system, which is 8 TB.
801          */
802         s->s_maxbytes = 0x80000000000LL;
803 
804         /* ECMA-119 timestamp from 1900/1/1 with tz offset */
805         s->s_time_min = mktime64(1900, 1, 1, 0, 0, 0) - MAX_TZ_OFFSET;
806         s->s_time_max = mktime64(U8_MAX+1900, 12, 31, 23, 59, 59) + MAX_TZ_OFFSET;
807 
808         /* Set this for reference. Its not currently used except on write
809            which we don't have .. */
810 
811         first_data_zone = isonum_733(rootp->extent) +
812                           isonum_711(rootp->ext_attr_length);
813         sbi->s_firstdatazone = first_data_zone;
814 #ifndef BEQUIET
815         printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
816                 sbi->s_max_size, 1UL << sbi->s_log_zone_size);
817         printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
818         if(sbi->s_high_sierra)
819                 printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
820 #endif
821 
822         /*
823          * If the Joliet level is set, we _may_ decide to use the
824          * secondary descriptor, but can't be sure until after we
825          * read the root inode. But before reading the root inode
826          * we may need to change the device blocksize, and would
827          * rather release the old buffer first. So, we cache the
828          * first_data_zone value from the secondary descriptor.
829          */
830         if (joliet_level) {
831                 pri = (struct iso_primary_descriptor *) sec;
832                 rootp = (struct iso_directory_record *)
833                         pri->root_directory_record;
834                 first_data_zone = isonum_733(rootp->extent) +
835                                 isonum_711(rootp->ext_attr_length);
836         }
837 
838         /*
839          * We're all done using the volume descriptor, and may need
840          * to change the device blocksize, so release the buffer now.
841          */
842         brelse(pri_bh);
843         brelse(bh);
844 
845         /*
846          * Force the blocksize to 512 for 512 byte sectors.  The file
847          * read primitives really get it wrong in a bad way if we don't
848          * do this.
849          *
850          * Note - we should never be setting the blocksize to something
851          * less than the hardware sector size for the device.  If we
852          * do, we would end up having to read larger buffers and split
853          * out portions to satisfy requests.
854          *
855          * Note2- the idea here is that we want to deal with the optimal
856          * zonesize in the filesystem.  If we have it set to something less,
857          * then we have horrible problems with trying to piece together
858          * bits of adjacent blocks in order to properly read directory
859          * entries.  By forcing the blocksize in this way, we ensure
860          * that we will never be required to do this.
861          */
862         sb_set_blocksize(s, orig_zonesize);
863 
864         sbi->s_nls_iocharset = NULL;
865 
866 #ifdef CONFIG_JOLIET
867         if (joliet_level) {
868                 char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
869                 if (strcmp(p, "utf8") != 0) {
870                         sbi->s_nls_iocharset = opt.iocharset ?
871                                 load_nls(opt.iocharset) : load_nls_default();
872                         if (!sbi->s_nls_iocharset)
873                                 goto out_freesbi;
874                 }
875         }
876 #endif
877         s->s_op = &isofs_sops;
878         s->s_export_op = &isofs_export_ops;
879         sbi->s_mapping = opt.map;
880         sbi->s_rock = (opt.rock ? 2 : 0);
881         sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
882         sbi->s_cruft = opt.cruft;
883         sbi->s_hide = opt.hide;
884         sbi->s_showassoc = opt.showassoc;
885         sbi->s_uid = opt.uid;
886         sbi->s_gid = opt.gid;
887         sbi->s_uid_set = opt.uid_set;
888         sbi->s_gid_set = opt.gid_set;
889         sbi->s_nocompress = opt.nocompress;
890         sbi->s_overriderockperm = opt.overriderockperm;
891         /*
892          * It would be incredibly stupid to allow people to mark every file
893          * on the disk as suid, so we merely allow them to set the default
894          * permissions.
895          */
896         if (opt.fmode != ISOFS_INVALID_MODE)
897                 sbi->s_fmode = opt.fmode & 0777;
898         else
899                 sbi->s_fmode = ISOFS_INVALID_MODE;
900         if (opt.dmode != ISOFS_INVALID_MODE)
901                 sbi->s_dmode = opt.dmode & 0777;
902         else
903                 sbi->s_dmode = ISOFS_INVALID_MODE;
904 
905         /*
906          * Read the root inode, which _may_ result in changing
907          * the s_rock flag. Once we have the final s_rock value,
908          * we then decide whether to use the Joliet descriptor.
909          */
910         inode = isofs_iget(s, sbi->s_firstdatazone, 0);
911         if (IS_ERR(inode))
912                 goto out_no_root;
913 
914         /*
915          * Fix for broken CDs with Rock Ridge and empty ISO root directory but
916          * correct Joliet root directory.
917          */
918         if (sbi->s_rock == 1 && joliet_level &&
919                                 rootdir_empty(s, sbi->s_firstdatazone)) {
920                 printk(KERN_NOTICE
921                         "ISOFS: primary root directory is empty. "
922                         "Disabling Rock Ridge and switching to Joliet.");
923                 sbi->s_rock = 0;
924         }
925 
926         /*
927          * If this disk has both Rock Ridge and Joliet on it, then we
928          * want to use Rock Ridge by default.  This can be overridden
929          * by using the norock mount option.  There is still one other
930          * possibility that is not taken into account: a Rock Ridge
931          * CD with Unicode names.  Until someone sees such a beast, it
932          * will not be supported.
933          */
934         if (sbi->s_rock == 1) {
935                 joliet_level = 0;
936         } else if (joliet_level) {
937                 sbi->s_rock = 0;
938                 if (sbi->s_firstdatazone != first_data_zone) {
939                         sbi->s_firstdatazone = first_data_zone;
940                         printk(KERN_DEBUG
941                                 "ISOFS: changing to secondary root\n");
942                         iput(inode);
943                         inode = isofs_iget(s, sbi->s_firstdatazone, 0);
944                         if (IS_ERR(inode))
945                                 goto out_no_root;
946                 }
947         }
948 
949         if (opt.check == 'u') {
950                 /* Only Joliet is case insensitive by default */
951                 if (joliet_level)
952                         opt.check = 'r';
953                 else
954                         opt.check = 's';
955         }
956         sbi->s_joliet_level = joliet_level;
957 
958         /* Make sure the root inode is a directory */
959         if (!S_ISDIR(inode->i_mode)) {
960                 printk(KERN_WARNING
961                         "isofs_fill_super: root inode is not a directory. "
962                         "Corrupted media?\n");
963                 goto out_iput;
964         }
965 
966         table = 0;
967         if (joliet_level)
968                 table += 2;
969         if (opt.check == 'r')
970                 table++;
971         sbi->s_check = opt.check;
972 
973         if (table)
974                 s->s_d_op = &isofs_dentry_ops[table - 1];
975 
976         /* get the root dentry */
977         s->s_root = d_make_root(inode);
978         if (!(s->s_root)) {
979                 error = -ENOMEM;
980                 goto out_no_inode;
981         }
982 
983         kfree(opt.iocharset);
984 
985         return 0;
986 
987         /*
988          * Display error messages and free resources.
989          */
990 out_iput:
991         iput(inode);
992         goto out_no_inode;
993 out_no_root:
994         error = PTR_ERR(inode);
995         if (error != -ENOMEM)
996                 printk(KERN_WARNING "%s: get root inode failed\n", __func__);
997 out_no_inode:
998 #ifdef CONFIG_JOLIET
999         unload_nls(sbi->s_nls_iocharset);
1000 #endif
1001         goto out_freesbi;
1002 out_no_read:
1003         printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
1004                 __func__, s->s_id, iso_blknum, block);
1005         goto out_freebh;
1006 out_bad_zone_size:
1007         printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
1008                 sbi->s_log_zone_size);
1009         goto out_freebh;
1010 out_bad_size:
1011         printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
1012                 orig_zonesize, opt.blocksize);
1013         goto out_freebh;
1014 out_unknown_format:
1015         if (!silent)
1016                 printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
1017 
1018 out_freebh:
1019         brelse(bh);
1020         brelse(pri_bh);
1021 out_freesbi:
1022         kfree(opt.iocharset);
1023         kfree(sbi);
1024         s->s_fs_info = NULL;
1025         return error;
1026 }
1027 
1028 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
1029 {
1030         struct super_block *sb = dentry->d_sb;
1031         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1032 
1033         buf->f_type = ISOFS_SUPER_MAGIC;
1034         buf->f_bsize = sb->s_blocksize;
1035         buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1036                 << (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1037         buf->f_bfree = 0;
1038         buf->f_bavail = 0;
1039         buf->f_files = ISOFS_SB(sb)->s_ninodes;
1040         buf->f_ffree = 0;
1041         buf->f_fsid = u64_to_fsid(id);
1042         buf->f_namelen = NAME_MAX;
1043         return 0;
1044 }
1045 
1046 /*
1047  * Get a set of blocks; filling in buffer_heads if already allocated
1048  * or getblk() if they are not.  Returns the number of blocks inserted
1049  * (-ve == error.)
1050  */
1051 int isofs_get_blocks(struct inode *inode, sector_t iblock,
1052                      struct buffer_head **bh, unsigned long nblocks)
1053 {
1054         unsigned long b_off = iblock;
1055         unsigned offset, sect_size;
1056         unsigned int firstext;
1057         unsigned long nextblk, nextoff;
1058         int section, rv, error;
1059         struct iso_inode_info *ei = ISOFS_I(inode);
1060 
1061         error = -EIO;
1062         rv = 0;
1063         if (iblock != b_off) {
1064                 printk(KERN_DEBUG "%s: block number too large\n", __func__);
1065                 goto abort;
1066         }
1067 
1068 
1069         offset = 0;
1070         firstext = ei->i_first_extent;
1071         sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1072         nextblk = ei->i_next_section_block;
1073         nextoff = ei->i_next_section_offset;
1074         section = 0;
1075 
1076         while (nblocks) {
1077                 /* If we are *way* beyond the end of the file, print a message.
1078                  * Access beyond the end of the file up to the next page boundary
1079                  * is normal, however because of the way the page cache works.
1080                  * In this case, we just return 0 so that we can properly fill
1081                  * the page with useless information without generating any
1082                  * I/O errors.
1083                  */
1084                 if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1085                         printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1086                                 __func__, b_off,
1087                                 (unsigned long long)inode->i_size);
1088                         goto abort;
1089                 }
1090 
1091                 /* On the last section, nextblk == 0, section size is likely to
1092                  * exceed sect_size by a partial block, and access beyond the
1093                  * end of the file will reach beyond the section size, too.
1094                  */
1095                 while (nextblk && (b_off >= (offset + sect_size))) {
1096                         struct inode *ninode;
1097 
1098                         offset += sect_size;
1099                         ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1100                         if (IS_ERR(ninode)) {
1101                                 error = PTR_ERR(ninode);
1102                                 goto abort;
1103                         }
1104                         firstext  = ISOFS_I(ninode)->i_first_extent;
1105                         sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1106                         nextblk   = ISOFS_I(ninode)->i_next_section_block;
1107                         nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1108                         iput(ninode);
1109 
1110                         if (++section > 100) {
1111                                 printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1112                                         " aborting...\n", __func__);
1113                                 printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1114                                         "nextblk=%lu nextoff=%lu\n", __func__,
1115                                         b_off, firstext, (unsigned) sect_size,
1116                                         nextblk, nextoff);
1117                                 goto abort;
1118                         }
1119                 }
1120 
1121                 if (*bh) {
1122                         map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1123                 } else {
1124                         *bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1125                         if (!*bh)
1126                                 goto abort;
1127                 }
1128                 bh++;   /* Next buffer head */
1129                 b_off++;        /* Next buffer offset */
1130                 nblocks--;
1131                 rv++;
1132         }
1133 
1134         error = 0;
1135 abort:
1136         return rv != 0 ? rv : error;
1137 }
1138 
1139 /*
1140  * Used by the standard interfaces.
1141  */
1142 static int isofs_get_block(struct inode *inode, sector_t iblock,
1143                     struct buffer_head *bh_result, int create)
1144 {
1145         int ret;
1146 
1147         if (create) {
1148                 printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1149                 return -EROFS;
1150         }
1151 
1152         ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1153         return ret < 0 ? ret : 0;
1154 }
1155 
1156 static int isofs_bmap(struct inode *inode, sector_t block)
1157 {
1158         struct buffer_head dummy;
1159         int error;
1160 
1161         dummy.b_state = 0;
1162         dummy.b_blocknr = -1000;
1163         error = isofs_get_block(inode, block, &dummy, 0);
1164         if (!error)
1165                 return dummy.b_blocknr;
1166         return 0;
1167 }
1168 
1169 struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1170 {
1171         sector_t blknr = isofs_bmap(inode, block);
1172         if (!blknr)
1173                 return NULL;
1174         return sb_bread(inode->i_sb, blknr);
1175 }
1176 
1177 static int isofs_readpage(struct file *file, struct page *page)
1178 {
1179         return mpage_readpage(page, isofs_get_block);
1180 }
1181 
1182 static void isofs_readahead(struct readahead_control *rac)
1183 {
1184         mpage_readahead(rac, isofs_get_block);
1185 }
1186 
1187 static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1188 {
1189         return generic_block_bmap(mapping,block,isofs_get_block);
1190 }
1191 
1192 static const struct address_space_operations isofs_aops = {
1193         .readpage = isofs_readpage,
1194         .readahead = isofs_readahead,
1195         .bmap = _isofs_bmap
1196 };
1197 
1198 static int isofs_read_level3_size(struct inode *inode)
1199 {
1200         unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1201         int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1202         struct buffer_head *bh = NULL;
1203         unsigned long block, offset, block_saved, offset_saved;
1204         int i = 0;
1205         int more_entries = 0;
1206         struct iso_directory_record *tmpde = NULL;
1207         struct iso_inode_info *ei = ISOFS_I(inode);
1208 
1209         inode->i_size = 0;
1210 
1211         /* The first 16 blocks are reserved as the System Area.  Thus,
1212          * no inodes can appear in block 0.  We use this to flag that
1213          * this is the last section. */
1214         ei->i_next_section_block = 0;
1215         ei->i_next_section_offset = 0;
1216 
1217         block = ei->i_iget5_block;
1218         offset = ei->i_iget5_offset;
1219 
1220         do {
1221                 struct iso_directory_record *de;
1222                 unsigned int de_len;
1223 
1224                 if (!bh) {
1225                         bh = sb_bread(inode->i_sb, block);
1226                         if (!bh)
1227                                 goto out_noread;
1228                 }
1229                 de = (struct iso_directory_record *) (bh->b_data + offset);
1230                 de_len = *(unsigned char *) de;
1231 
1232                 if (de_len == 0) {
1233                         brelse(bh);
1234                         bh = NULL;
1235                         ++block;
1236                         offset = 0;
1237                         continue;
1238                 }
1239 
1240                 block_saved = block;
1241                 offset_saved = offset;
1242                 offset += de_len;
1243 
1244                 /* Make sure we have a full directory entry */
1245                 if (offset >= bufsize) {
1246                         int slop = bufsize - offset + de_len;
1247                         if (!tmpde) {
1248                                 tmpde = kmalloc(256, GFP_KERNEL);
1249                                 if (!tmpde)
1250                                         goto out_nomem;
1251                         }
1252                         memcpy(tmpde, de, slop);
1253                         offset &= bufsize - 1;
1254                         block++;
1255                         brelse(bh);
1256                         bh = NULL;
1257                         if (offset) {
1258                                 bh = sb_bread(inode->i_sb, block);
1259                                 if (!bh)
1260                                         goto out_noread;
1261                                 memcpy((void *)tmpde+slop, bh->b_data, offset);
1262                         }
1263                         de = tmpde;
1264                 }
1265 
1266                 inode->i_size += isonum_733(de->size);
1267                 if (i == 1) {
1268                         ei->i_next_section_block = block_saved;
1269                         ei->i_next_section_offset = offset_saved;
1270                 }
1271 
1272                 more_entries = de->flags[-high_sierra] & 0x80;
1273 
1274                 i++;
1275                 if (i > 100)
1276                         goto out_toomany;
1277         } while (more_entries);
1278 out:
1279         kfree(tmpde);
1280         if (bh)
1281                 brelse(bh);
1282         return 0;
1283 
1284 out_nomem:
1285         if (bh)
1286                 brelse(bh);
1287         return -ENOMEM;
1288 
1289 out_noread:
1290         printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1291         kfree(tmpde);
1292         return -EIO;
1293 
1294 out_toomany:
1295         printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1296                 "isofs_read_level3_size: inode=%lu\n",
1297                 __func__, inode->i_ino);
1298         goto out;
1299 }
1300 
1301 static int isofs_read_inode(struct inode *inode, int relocated)
1302 {
1303         struct super_block *sb = inode->i_sb;
1304         struct isofs_sb_info *sbi = ISOFS_SB(sb);
1305         unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1306         unsigned long block;
1307         int high_sierra = sbi->s_high_sierra;
1308         struct buffer_head *bh;
1309         struct iso_directory_record *de;
1310         struct iso_directory_record *tmpde = NULL;
1311         unsigned int de_len;
1312         unsigned long offset;
1313         struct iso_inode_info *ei = ISOFS_I(inode);
1314         int ret = -EIO;
1315 
1316         block = ei->i_iget5_block;
1317         bh = sb_bread(inode->i_sb, block);
1318         if (!bh)
1319                 goto out_badread;
1320 
1321         offset = ei->i_iget5_offset;
1322 
1323         de = (struct iso_directory_record *) (bh->b_data + offset);
1324         de_len = *(unsigned char *) de;
1325 
1326         if (offset + de_len > bufsize) {
1327                 int frag1 = bufsize - offset;
1328 
1329                 tmpde = kmalloc(de_len, GFP_KERNEL);
1330                 if (!tmpde) {
1331                         ret = -ENOMEM;
1332                         goto fail;
1333                 }
1334                 memcpy(tmpde, bh->b_data + offset, frag1);
1335                 brelse(bh);
1336                 bh = sb_bread(inode->i_sb, ++block);
1337                 if (!bh)
1338                         goto out_badread;
1339                 memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1340                 de = tmpde;
1341         }
1342 
1343         inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1344                                         ei->i_iget5_offset,
1345                                         ISOFS_BUFFER_BITS(inode));
1346 
1347         /* Assume it is a normal-format file unless told otherwise */
1348         ei->i_file_format = isofs_file_normal;
1349 
1350         if (de->flags[-high_sierra] & 2) {
1351                 if (sbi->s_dmode != ISOFS_INVALID_MODE)
1352                         inode->i_mode = S_IFDIR | sbi->s_dmode;
1353                 else
1354                         inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1355                 set_nlink(inode, 1);    /*
1356                                          * Set to 1.  We know there are 2, but
1357                                          * the find utility tries to optimize
1358                                          * if it is 2, and it screws up.  It is
1359                                          * easier to give 1 which tells find to
1360                                          * do it the hard way.
1361                                          */
1362         } else {
1363                 if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1364                         inode->i_mode = S_IFREG | sbi->s_fmode;
1365                 } else {
1366                         /*
1367                          * Set default permissions: r-x for all.  The disc
1368                          * could be shared with DOS machines so virtually
1369                          * anything could be a valid executable.
1370                          */
1371                         inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1372                 }
1373                 set_nlink(inode, 1);
1374         }
1375         inode->i_uid = sbi->s_uid;
1376         inode->i_gid = sbi->s_gid;
1377         inode->i_blocks = 0;
1378 
1379         ei->i_format_parm[0] = 0;
1380         ei->i_format_parm[1] = 0;
1381         ei->i_format_parm[2] = 0;
1382 
1383         ei->i_section_size = isonum_733(de->size);
1384         if (de->flags[-high_sierra] & 0x80) {
1385                 ret = isofs_read_level3_size(inode);
1386                 if (ret < 0)
1387                         goto fail;
1388                 ret = -EIO;
1389         } else {
1390                 ei->i_next_section_block = 0;
1391                 ei->i_next_section_offset = 0;
1392                 inode->i_size = isonum_733(de->size);
1393         }
1394 
1395         /*
1396          * Some dipshit decided to store some other bit of information
1397          * in the high byte of the file length.  Truncate size in case
1398          * this CDROM was mounted with the cruft option.
1399          */
1400 
1401         if (sbi->s_cruft)
1402                 inode->i_size &= 0x00ffffff;
1403 
1404         if (de->interleave[0]) {
1405                 printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1406                 inode->i_size = 0;
1407         }
1408 
1409         /* I have no idea what file_unit_size is used for, so
1410            we will flag it for now */
1411         if (de->file_unit_size[0] != 0) {
1412                 printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1413                         inode->i_ino);
1414         }
1415 
1416         /* I have no idea what other flag bits are used for, so
1417            we will flag it for now */
1418 #ifdef DEBUG
1419         if((de->flags[-high_sierra] & ~2)!= 0){
1420                 printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1421                                 "(%ld %x).\n",
1422                         inode->i_ino, de->flags[-high_sierra]);
1423         }
1424 #endif
1425 
1426         inode->i_mtime.tv_sec =
1427         inode->i_atime.tv_sec =
1428         inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
1429         inode->i_mtime.tv_nsec =
1430         inode->i_atime.tv_nsec =
1431         inode->i_ctime.tv_nsec = 0;
1432 
1433         ei->i_first_extent = (isonum_733(de->extent) +
1434                         isonum_711(de->ext_attr_length));
1435 
1436         /* Set the number of blocks for stat() - should be done before RR */
1437         inode->i_blocks = (inode->i_size + 511) >> 9;
1438 
1439         /*
1440          * Now test for possible Rock Ridge extensions which will override
1441          * some of these numbers in the inode structure.
1442          */
1443 
1444         if (!high_sierra) {
1445                 parse_rock_ridge_inode(de, inode, relocated);
1446                 /* if we want uid/gid set, override the rock ridge setting */
1447                 if (sbi->s_uid_set)
1448                         inode->i_uid = sbi->s_uid;
1449                 if (sbi->s_gid_set)
1450                         inode->i_gid = sbi->s_gid;
1451         }
1452         /* Now set final access rights if overriding rock ridge setting */
1453         if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1454             sbi->s_dmode != ISOFS_INVALID_MODE)
1455                 inode->i_mode = S_IFDIR | sbi->s_dmode;
1456         if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1457             sbi->s_fmode != ISOFS_INVALID_MODE)
1458                 inode->i_mode = S_IFREG | sbi->s_fmode;
1459 
1460         /* Install the inode operations vector */
1461         if (S_ISREG(inode->i_mode)) {
1462                 inode->i_fop = &generic_ro_fops;
1463                 switch (ei->i_file_format) {
1464 #ifdef CONFIG_ZISOFS
1465                 case isofs_file_compressed:
1466                         inode->i_data.a_ops = &zisofs_aops;
1467                         break;
1468 #endif
1469                 default:
1470                         inode->i_data.a_ops = &isofs_aops;
1471                         break;
1472                 }
1473         } else if (S_ISDIR(inode->i_mode)) {
1474                 inode->i_op = &isofs_dir_inode_operations;
1475                 inode->i_fop = &isofs_dir_operations;
1476         } else if (S_ISLNK(inode->i_mode)) {
1477                 inode->i_op = &page_symlink_inode_operations;
1478                 inode_nohighmem(inode);
1479                 inode->i_data.a_ops = &isofs_symlink_aops;
1480         } else
1481                 /* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1482                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
1483 
1484         ret = 0;
1485 out:
1486         kfree(tmpde);
1487         if (bh)
1488                 brelse(bh);
1489         return ret;
1490 
1491 out_badread:
1492         printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1493 fail:
1494         goto out;
1495 }
1496 
1497 struct isofs_iget5_callback_data {
1498         unsigned long block;
1499         unsigned long offset;
1500 };
1501 
1502 static int isofs_iget5_test(struct inode *ino, void *data)
1503 {
1504         struct iso_inode_info *i = ISOFS_I(ino);
1505         struct isofs_iget5_callback_data *d =
1506                 (struct isofs_iget5_callback_data*)data;
1507         return (i->i_iget5_block == d->block)
1508                 && (i->i_iget5_offset == d->offset);
1509 }
1510 
1511 static int isofs_iget5_set(struct inode *ino, void *data)
1512 {
1513         struct iso_inode_info *i = ISOFS_I(ino);
1514         struct isofs_iget5_callback_data *d =
1515                 (struct isofs_iget5_callback_data*)data;
1516         i->i_iget5_block = d->block;
1517         i->i_iget5_offset = d->offset;
1518         return 0;
1519 }
1520 
1521 /* Store, in the inode's containing structure, the block and block
1522  * offset that point to the underlying meta-data for the inode.  The
1523  * code below is otherwise similar to the iget() code in
1524  * include/linux/fs.h */
1525 struct inode *__isofs_iget(struct super_block *sb,
1526                            unsigned long block,
1527                            unsigned long offset,
1528                            int relocated)
1529 {
1530         unsigned long hashval;
1531         struct inode *inode;
1532         struct isofs_iget5_callback_data data;
1533         long ret;
1534 
1535         if (offset >= 1ul << sb->s_blocksize_bits)
1536                 return ERR_PTR(-EINVAL);
1537 
1538         data.block = block;
1539         data.offset = offset;
1540 
1541         hashval = (block << sb->s_blocksize_bits) | offset;
1542 
1543         inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1544                                 &isofs_iget5_set, &data);
1545 
1546         if (!inode)
1547                 return ERR_PTR(-ENOMEM);
1548 
1549         if (inode->i_state & I_NEW) {
1550                 ret = isofs_read_inode(inode, relocated);
1551                 if (ret < 0) {
1552                         iget_failed(inode);
1553                         inode = ERR_PTR(ret);
1554                 } else {
1555                         unlock_new_inode(inode);
1556                 }
1557         }
1558 
1559         return inode;
1560 }
1561 
1562 static struct dentry *isofs_mount(struct file_system_type *fs_type,
1563         int flags, const char *dev_name, void *data)
1564 {
1565         return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1566 }
1567 
1568 static struct file_system_type iso9660_fs_type = {
1569         .owner          = THIS_MODULE,
1570         .name           = "iso9660",
1571         .mount          = isofs_mount,
1572         .kill_sb        = kill_block_super,
1573         .fs_flags       = FS_REQUIRES_DEV,
1574 };
1575 MODULE_ALIAS_FS("iso9660");
1576 MODULE_ALIAS("iso9660");
1577 
1578 static int __init init_iso9660_fs(void)
1579 {
1580         int err = init_inodecache();
1581         if (err)
1582                 goto out;
1583 #ifdef CONFIG_ZISOFS
1584         err = zisofs_init();
1585         if (err)
1586                 goto out1;
1587 #endif
1588         err = register_filesystem(&iso9660_fs_type);
1589         if (err)
1590                 goto out2;
1591         return 0;
1592 out2:
1593 #ifdef CONFIG_ZISOFS
1594         zisofs_cleanup();
1595 out1:
1596 #endif
1597         destroy_inodecache();
1598 out:
1599         return err;
1600 }
1601 
1602 static void __exit exit_iso9660_fs(void)
1603 {
1604         unregister_filesystem(&iso9660_fs_type);
1605 #ifdef CONFIG_ZISOFS
1606         zisofs_cleanup();
1607 #endif
1608         destroy_inodecache();
1609 }
1610 
1611 module_init(init_iso9660_fs)
1612 module_exit(exit_iso9660_fs)
1613 MODULE_LICENSE("GPL");
1614 

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