xref: /openbmc/linux/fs/isofs/inode.c (revision 4da722ca)
1 /*
2  *  linux/fs/isofs/inode.c
3  *
4  *  (C) 1991  Linus Torvalds - minix filesystem
5  *      1992, 1993, 1994  Eric Youngdale Modified for ISO 9660 filesystem.
6  *      1994  Eberhard Mönkeberg - multi session handling.
7  *      1995  Mark Dobie - allow mounting of some weird VideoCDs and PhotoCDs.
8  *	1997  Gordon Chaffee - Joliet CDs
9  *	1998  Eric Lammerts - ISO 9660 Level 3
10  *	2004  Paul Serice - Inode Support pushed out from 4GB to 128GB
11  *	2004  Paul Serice - NFS Export Operations
12  */
13 
14 #include <linux/init.h>
15 #include <linux/module.h>
16 
17 #include <linux/slab.h>
18 #include <linux/cred.h>
19 #include <linux/nls.h>
20 #include <linux/ctype.h>
21 #include <linux/statfs.h>
22 #include <linux/cdrom.h>
23 #include <linux/parser.h>
24 #include <linux/mpage.h>
25 #include <linux/user_namespace.h>
26 #include <linux/seq_file.h>
27 
28 #include "isofs.h"
29 #include "zisofs.h"
30 
31 #define BEQUIET
32 
33 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
34 static int isofs_dentry_cmpi(const struct dentry *dentry,
35 		unsigned int len, const char *str, const struct qstr *name);
36 
37 #ifdef CONFIG_JOLIET
38 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
39 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
40 static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
41 		unsigned int len, const char *str, const struct qstr *name);
42 static int isofs_dentry_cmp_ms(const struct dentry *dentry,
43 		unsigned int len, const char *str, const struct qstr *name);
44 #endif
45 
46 static void isofs_put_super(struct super_block *sb)
47 {
48 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
49 
50 #ifdef CONFIG_JOLIET
51 	unload_nls(sbi->s_nls_iocharset);
52 #endif
53 
54 	kfree(sbi);
55 	sb->s_fs_info = NULL;
56 	return;
57 }
58 
59 static int isofs_read_inode(struct inode *, int relocated);
60 static int isofs_statfs (struct dentry *, struct kstatfs *);
61 static int isofs_show_options(struct seq_file *, struct dentry *);
62 
63 static struct kmem_cache *isofs_inode_cachep;
64 
65 static struct inode *isofs_alloc_inode(struct super_block *sb)
66 {
67 	struct iso_inode_info *ei;
68 	ei = kmem_cache_alloc(isofs_inode_cachep, GFP_KERNEL);
69 	if (!ei)
70 		return NULL;
71 	return &ei->vfs_inode;
72 }
73 
74 static void isofs_i_callback(struct rcu_head *head)
75 {
76 	struct inode *inode = container_of(head, struct inode, i_rcu);
77 	kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
78 }
79 
80 static void isofs_destroy_inode(struct inode *inode)
81 {
82 	call_rcu(&inode->i_rcu, isofs_i_callback);
83 }
84 
85 static void init_once(void *foo)
86 {
87 	struct iso_inode_info *ei = foo;
88 
89 	inode_init_once(&ei->vfs_inode);
90 }
91 
92 static int __init init_inodecache(void)
93 {
94 	isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
95 					sizeof(struct iso_inode_info),
96 					0, (SLAB_RECLAIM_ACCOUNT|
97 					SLAB_MEM_SPREAD|SLAB_ACCOUNT),
98 					init_once);
99 	if (isofs_inode_cachep == NULL)
100 		return -ENOMEM;
101 	return 0;
102 }
103 
104 static void destroy_inodecache(void)
105 {
106 	/*
107 	 * Make sure all delayed rcu free inodes are flushed before we
108 	 * destroy cache.
109 	 */
110 	rcu_barrier();
111 	kmem_cache_destroy(isofs_inode_cachep);
112 }
113 
114 static int isofs_remount(struct super_block *sb, int *flags, char *data)
115 {
116 	sync_filesystem(sb);
117 	if (!(*flags & MS_RDONLY))
118 		return -EROFS;
119 	return 0;
120 }
121 
122 static const struct super_operations isofs_sops = {
123 	.alloc_inode	= isofs_alloc_inode,
124 	.destroy_inode	= isofs_destroy_inode,
125 	.put_super	= isofs_put_super,
126 	.statfs		= isofs_statfs,
127 	.remount_fs	= isofs_remount,
128 	.show_options	= isofs_show_options,
129 };
130 
131 
132 static const struct dentry_operations isofs_dentry_ops[] = {
133 	{
134 		.d_hash		= isofs_hashi,
135 		.d_compare	= isofs_dentry_cmpi,
136 	},
137 #ifdef CONFIG_JOLIET
138 	{
139 		.d_hash		= isofs_hash_ms,
140 		.d_compare	= isofs_dentry_cmp_ms,
141 	},
142 	{
143 		.d_hash		= isofs_hashi_ms,
144 		.d_compare	= isofs_dentry_cmpi_ms,
145 	},
146 #endif
147 };
148 
149 struct iso9660_options{
150 	unsigned int rock:1;
151 	unsigned int joliet:1;
152 	unsigned int cruft:1;
153 	unsigned int hide:1;
154 	unsigned int showassoc:1;
155 	unsigned int nocompress:1;
156 	unsigned int overriderockperm:1;
157 	unsigned int uid_set:1;
158 	unsigned int gid_set:1;
159 	unsigned int utf8:1;
160 	unsigned char map;
161 	unsigned char check;
162 	unsigned int blocksize;
163 	umode_t fmode;
164 	umode_t dmode;
165 	kgid_t gid;
166 	kuid_t uid;
167 	char *iocharset;
168 	/* LVE */
169 	s32 session;
170 	s32 sbsector;
171 };
172 
173 /*
174  * Compute the hash for the isofs name corresponding to the dentry.
175  */
176 static int
177 isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
178 {
179 	const char *name;
180 	int len;
181 	char c;
182 	unsigned long hash;
183 
184 	len = qstr->len;
185 	name = qstr->name;
186 	if (ms) {
187 		while (len && name[len-1] == '.')
188 			len--;
189 	}
190 
191 	hash = init_name_hash(dentry);
192 	while (len--) {
193 		c = tolower(*name++);
194 		hash = partial_name_hash(c, hash);
195 	}
196 	qstr->hash = end_name_hash(hash);
197 
198 	return 0;
199 }
200 
201 /*
202  * Compare of two isofs names.
203  */
204 static int isofs_dentry_cmp_common(
205 		unsigned int len, const char *str,
206 		const struct qstr *name, int ms, int ci)
207 {
208 	int alen, blen;
209 
210 	/* A filename cannot end in '.' or we treat it like it has none */
211 	alen = name->len;
212 	blen = len;
213 	if (ms) {
214 		while (alen && name->name[alen-1] == '.')
215 			alen--;
216 		while (blen && str[blen-1] == '.')
217 			blen--;
218 	}
219 	if (alen == blen) {
220 		if (ci) {
221 			if (strncasecmp(name->name, str, alen) == 0)
222 				return 0;
223 		} else {
224 			if (strncmp(name->name, str, alen) == 0)
225 				return 0;
226 		}
227 	}
228 	return 1;
229 }
230 
231 static int
232 isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
233 {
234 	return isofs_hashi_common(dentry, qstr, 0);
235 }
236 
237 static int
238 isofs_dentry_cmpi(const struct dentry *dentry,
239 		unsigned int len, const char *str, const struct qstr *name)
240 {
241 	return isofs_dentry_cmp_common(len, str, name, 0, 1);
242 }
243 
244 #ifdef CONFIG_JOLIET
245 /*
246  * Compute the hash for the isofs name corresponding to the dentry.
247  */
248 static int
249 isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
250 {
251 	const char *name;
252 	int len;
253 
254 	len = qstr->len;
255 	name = qstr->name;
256 	if (ms) {
257 		while (len && name[len-1] == '.')
258 			len--;
259 	}
260 
261 	qstr->hash = full_name_hash(dentry, name, len);
262 
263 	return 0;
264 }
265 
266 static int
267 isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
268 {
269 	return isofs_hash_common(dentry, qstr, 1);
270 }
271 
272 static int
273 isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
274 {
275 	return isofs_hashi_common(dentry, qstr, 1);
276 }
277 
278 static int
279 isofs_dentry_cmp_ms(const struct dentry *dentry,
280 		unsigned int len, const char *str, const struct qstr *name)
281 {
282 	return isofs_dentry_cmp_common(len, str, name, 1, 0);
283 }
284 
285 static int
286 isofs_dentry_cmpi_ms(const struct dentry *dentry,
287 		unsigned int len, const char *str, const struct qstr *name)
288 {
289 	return isofs_dentry_cmp_common(len, str, name, 1, 1);
290 }
291 #endif
292 
293 enum {
294 	Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
295 	Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
296 	Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
297 	Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
298 };
299 
300 static const match_table_t tokens = {
301 	{Opt_norock, "norock"},
302 	{Opt_nojoliet, "nojoliet"},
303 	{Opt_unhide, "unhide"},
304 	{Opt_hide, "hide"},
305 	{Opt_showassoc, "showassoc"},
306 	{Opt_cruft, "cruft"},
307 	{Opt_utf8, "utf8"},
308 	{Opt_iocharset, "iocharset=%s"},
309 	{Opt_map_a, "map=acorn"},
310 	{Opt_map_a, "map=a"},
311 	{Opt_map_n, "map=normal"},
312 	{Opt_map_n, "map=n"},
313 	{Opt_map_o, "map=off"},
314 	{Opt_map_o, "map=o"},
315 	{Opt_session, "session=%u"},
316 	{Opt_sb, "sbsector=%u"},
317 	{Opt_check_r, "check=relaxed"},
318 	{Opt_check_r, "check=r"},
319 	{Opt_check_s, "check=strict"},
320 	{Opt_check_s, "check=s"},
321 	{Opt_uid, "uid=%u"},
322 	{Opt_gid, "gid=%u"},
323 	{Opt_mode, "mode=%u"},
324 	{Opt_dmode, "dmode=%u"},
325 	{Opt_overriderockperm, "overriderockperm"},
326 	{Opt_block, "block=%u"},
327 	{Opt_ignore, "conv=binary"},
328 	{Opt_ignore, "conv=b"},
329 	{Opt_ignore, "conv=text"},
330 	{Opt_ignore, "conv=t"},
331 	{Opt_ignore, "conv=mtext"},
332 	{Opt_ignore, "conv=m"},
333 	{Opt_ignore, "conv=auto"},
334 	{Opt_ignore, "conv=a"},
335 	{Opt_nocompress, "nocompress"},
336 	{Opt_err, NULL}
337 };
338 
339 static int parse_options(char *options, struct iso9660_options *popt)
340 {
341 	char *p;
342 	int option;
343 
344 	popt->map = 'n';
345 	popt->rock = 1;
346 	popt->joliet = 1;
347 	popt->cruft = 0;
348 	popt->hide = 0;
349 	popt->showassoc = 0;
350 	popt->check = 'u';		/* unset */
351 	popt->nocompress = 0;
352 	popt->blocksize = 1024;
353 	popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
354 	popt->uid_set = 0;
355 	popt->gid_set = 0;
356 	popt->gid = GLOBAL_ROOT_GID;
357 	popt->uid = GLOBAL_ROOT_UID;
358 	popt->iocharset = NULL;
359 	popt->utf8 = 0;
360 	popt->overriderockperm = 0;
361 	popt->session=-1;
362 	popt->sbsector=-1;
363 	if (!options)
364 		return 1;
365 
366 	while ((p = strsep(&options, ",")) != NULL) {
367 		int token;
368 		substring_t args[MAX_OPT_ARGS];
369 		unsigned n;
370 
371 		if (!*p)
372 			continue;
373 
374 		token = match_token(p, tokens, args);
375 		switch (token) {
376 		case Opt_norock:
377 			popt->rock = 0;
378 			break;
379 		case Opt_nojoliet:
380 			popt->joliet = 0;
381 			break;
382 		case Opt_hide:
383 			popt->hide = 1;
384 			break;
385 		case Opt_unhide:
386 		case Opt_showassoc:
387 			popt->showassoc = 1;
388 			break;
389 		case Opt_cruft:
390 			popt->cruft = 1;
391 			break;
392 		case Opt_utf8:
393 			popt->utf8 = 1;
394 			break;
395 #ifdef CONFIG_JOLIET
396 		case Opt_iocharset:
397 			popt->iocharset = match_strdup(&args[0]);
398 			break;
399 #endif
400 		case Opt_map_a:
401 			popt->map = 'a';
402 			break;
403 		case Opt_map_o:
404 			popt->map = 'o';
405 			break;
406 		case Opt_map_n:
407 			popt->map = 'n';
408 			break;
409 		case Opt_session:
410 			if (match_int(&args[0], &option))
411 				return 0;
412 			n = option;
413 			if (n > 99)
414 				return 0;
415 			popt->session = n + 1;
416 			break;
417 		case Opt_sb:
418 			if (match_int(&args[0], &option))
419 				return 0;
420 			popt->sbsector = option;
421 			break;
422 		case Opt_check_r:
423 			popt->check = 'r';
424 			break;
425 		case Opt_check_s:
426 			popt->check = 's';
427 			break;
428 		case Opt_ignore:
429 			break;
430 		case Opt_uid:
431 			if (match_int(&args[0], &option))
432 				return 0;
433 			popt->uid = make_kuid(current_user_ns(), option);
434 			if (!uid_valid(popt->uid))
435 				return 0;
436 			popt->uid_set = 1;
437 			break;
438 		case Opt_gid:
439 			if (match_int(&args[0], &option))
440 				return 0;
441 			popt->gid = make_kgid(current_user_ns(), option);
442 			if (!gid_valid(popt->gid))
443 				return 0;
444 			popt->gid_set = 1;
445 			break;
446 		case Opt_mode:
447 			if (match_int(&args[0], &option))
448 				return 0;
449 			popt->fmode = option;
450 			break;
451 		case Opt_dmode:
452 			if (match_int(&args[0], &option))
453 				return 0;
454 			popt->dmode = option;
455 			break;
456 		case Opt_overriderockperm:
457 			popt->overriderockperm = 1;
458 			break;
459 		case Opt_block:
460 			if (match_int(&args[0], &option))
461 				return 0;
462 			n = option;
463 			if (n != 512 && n != 1024 && n != 2048)
464 				return 0;
465 			popt->blocksize = n;
466 			break;
467 		case Opt_nocompress:
468 			popt->nocompress = 1;
469 			break;
470 		default:
471 			return 0;
472 		}
473 	}
474 	return 1;
475 }
476 
477 /*
478  * Display the mount options in /proc/mounts.
479  */
480 static int isofs_show_options(struct seq_file *m, struct dentry *root)
481 {
482 	struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
483 
484 	if (!sbi->s_rock)		seq_puts(m, ",norock");
485 	else if (!sbi->s_joliet_level)	seq_puts(m, ",nojoliet");
486 	if (sbi->s_cruft)		seq_puts(m, ",cruft");
487 	if (sbi->s_hide)		seq_puts(m, ",hide");
488 	if (sbi->s_nocompress)		seq_puts(m, ",nocompress");
489 	if (sbi->s_overriderockperm)	seq_puts(m, ",overriderockperm");
490 	if (sbi->s_showassoc)		seq_puts(m, ",showassoc");
491 	if (sbi->s_utf8)		seq_puts(m, ",utf8");
492 
493 	if (sbi->s_check)		seq_printf(m, ",check=%c", sbi->s_check);
494 	if (sbi->s_mapping)		seq_printf(m, ",map=%c", sbi->s_mapping);
495 	if (sbi->s_session != 255)	seq_printf(m, ",session=%u", sbi->s_session - 1);
496 	if (sbi->s_sbsector != -1)	seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
497 
498 	if (root->d_sb->s_blocksize != 1024)
499 		seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
500 
501 	if (sbi->s_uid_set)
502 		seq_printf(m, ",uid=%u",
503 			   from_kuid_munged(&init_user_ns, sbi->s_uid));
504 	if (sbi->s_gid_set)
505 		seq_printf(m, ",gid=%u",
506 			   from_kgid_munged(&init_user_ns, sbi->s_gid));
507 
508 	if (sbi->s_dmode != ISOFS_INVALID_MODE)
509 		seq_printf(m, ",dmode=%o", sbi->s_dmode);
510 	if (sbi->s_fmode != ISOFS_INVALID_MODE)
511 		seq_printf(m, ",fmode=%o", sbi->s_fmode);
512 
513 	if (sbi->s_nls_iocharset &&
514 	    strcmp(sbi->s_nls_iocharset->charset, CONFIG_NLS_DEFAULT) != 0)
515 		seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
516 	return 0;
517 }
518 
519 /*
520  * look if the driver can tell the multi session redirection value
521  *
522  * don't change this if you don't know what you do, please!
523  * Multisession is legal only with XA disks.
524  * A non-XA disk with more than one volume descriptor may do it right, but
525  * usually is written in a nowhere standardized "multi-partition" manner.
526  * Multisession uses absolute addressing (solely the first frame of the whole
527  * track is #0), multi-partition uses relative addressing (each first frame of
528  * each track is #0), and a track is not a session.
529  *
530  * A broken CDwriter software or drive firmware does not set new standards,
531  * at least not if conflicting with the existing ones.
532  *
533  * emoenke@gwdg.de
534  */
535 #define WE_OBEY_THE_WRITTEN_STANDARDS 1
536 
537 static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
538 {
539 	struct cdrom_multisession ms_info;
540 	unsigned int vol_desc_start;
541 	struct block_device *bdev = sb->s_bdev;
542 	int i;
543 
544 	vol_desc_start=0;
545 	ms_info.addr_format=CDROM_LBA;
546 	if(session >= 0 && session <= 99) {
547 		struct cdrom_tocentry Te;
548 		Te.cdte_track=session;
549 		Te.cdte_format=CDROM_LBA;
550 		i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
551 		if (!i) {
552 			printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
553 				session, Te.cdte_addr.lba,
554 				Te.cdte_ctrl&CDROM_DATA_TRACK);
555 			if ((Te.cdte_ctrl&CDROM_DATA_TRACK) == 4)
556 				return Te.cdte_addr.lba;
557 		}
558 
559 		printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
560 	}
561 	i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long) &ms_info);
562 	if (session > 0)
563 		printk(KERN_ERR "ISOFS: Invalid session number\n");
564 #if 0
565 	printk(KERN_DEBUG "isofs.inode: CDROMMULTISESSION: rc=%d\n",i);
566 	if (i==0) {
567 		printk(KERN_DEBUG "isofs.inode: XA disk: %s\n",ms_info.xa_flag?"yes":"no");
568 		printk(KERN_DEBUG "isofs.inode: vol_desc_start = %d\n", ms_info.addr.lba);
569 	}
570 #endif
571 	if (i==0)
572 #if WE_OBEY_THE_WRITTEN_STANDARDS
573 		if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
574 #endif
575 			vol_desc_start=ms_info.addr.lba;
576 	return vol_desc_start;
577 }
578 
579 /*
580  * Check if root directory is empty (has less than 3 files).
581  *
582  * Used to detect broken CDs where ISO root directory is empty but Joliet root
583  * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
584  * (and Joliet used instead) or else no files would be visible.
585  */
586 static bool rootdir_empty(struct super_block *sb, unsigned long block)
587 {
588 	int offset = 0, files = 0, de_len;
589 	struct iso_directory_record *de;
590 	struct buffer_head *bh;
591 
592 	bh = sb_bread(sb, block);
593 	if (!bh)
594 		return true;
595 	while (files < 3) {
596 		de = (struct iso_directory_record *) (bh->b_data + offset);
597 		de_len = *(unsigned char *) de;
598 		if (de_len == 0)
599 			break;
600 		files++;
601 		offset += de_len;
602 	}
603 	brelse(bh);
604 	return files < 3;
605 }
606 
607 /*
608  * Initialize the superblock and read the root inode.
609  *
610  * Note: a check_disk_change() has been done immediately prior
611  * to this call, so we don't need to check again.
612  */
613 static int isofs_fill_super(struct super_block *s, void *data, int silent)
614 {
615 	struct buffer_head *bh = NULL, *pri_bh = NULL;
616 	struct hs_primary_descriptor *h_pri = NULL;
617 	struct iso_primary_descriptor *pri = NULL;
618 	struct iso_supplementary_descriptor *sec = NULL;
619 	struct iso_directory_record *rootp;
620 	struct inode *inode;
621 	struct iso9660_options opt;
622 	struct isofs_sb_info *sbi;
623 	unsigned long first_data_zone;
624 	int joliet_level = 0;
625 	int iso_blknum, block;
626 	int orig_zonesize;
627 	int table, error = -EINVAL;
628 	unsigned int vol_desc_start;
629 
630 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
631 	if (!sbi)
632 		return -ENOMEM;
633 	s->s_fs_info = sbi;
634 
635 	if (!parse_options((char *)data, &opt))
636 		goto out_freesbi;
637 
638 	/*
639 	 * First of all, get the hardware blocksize for this device.
640 	 * If we don't know what it is, or the hardware blocksize is
641 	 * larger than the blocksize the user specified, then use
642 	 * that value.
643 	 */
644 	/*
645 	 * What if bugger tells us to go beyond page size?
646 	 */
647 	opt.blocksize = sb_min_blocksize(s, opt.blocksize);
648 
649 	sbi->s_high_sierra = 0; /* default is iso9660 */
650 	sbi->s_session = opt.session;
651 	sbi->s_sbsector = opt.sbsector;
652 
653 	vol_desc_start = (opt.sbsector != -1) ?
654 		opt.sbsector : isofs_get_last_session(s,opt.session);
655 
656 	for (iso_blknum = vol_desc_start+16;
657 		iso_blknum < vol_desc_start+100; iso_blknum++) {
658 		struct hs_volume_descriptor *hdp;
659 		struct iso_volume_descriptor  *vdp;
660 
661 		block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
662 		if (!(bh = sb_bread(s, block)))
663 			goto out_no_read;
664 
665 		vdp = (struct iso_volume_descriptor *)bh->b_data;
666 		hdp = (struct hs_volume_descriptor *)bh->b_data;
667 
668 		/*
669 		 * Due to the overlapping physical location of the descriptors,
670 		 * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
671 		 * proper identification in this case, we first check for ISO.
672 		 */
673 		if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
674 			if (isonum_711(vdp->type) == ISO_VD_END)
675 				break;
676 			if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
677 				if (pri == NULL) {
678 					pri = (struct iso_primary_descriptor *)vdp;
679 					/* Save the buffer in case we need it ... */
680 					pri_bh = bh;
681 					bh = NULL;
682 				}
683 			}
684 #ifdef CONFIG_JOLIET
685 			else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
686 				sec = (struct iso_supplementary_descriptor *)vdp;
687 				if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
688 					if (opt.joliet) {
689 						if (sec->escape[2] == 0x40)
690 							joliet_level = 1;
691 						else if (sec->escape[2] == 0x43)
692 							joliet_level = 2;
693 						else if (sec->escape[2] == 0x45)
694 							joliet_level = 3;
695 
696 						printk(KERN_DEBUG "ISO 9660 Extensions: "
697 							"Microsoft Joliet Level %d\n",
698 							joliet_level);
699 					}
700 					goto root_found;
701 				} else {
702 				/* Unknown supplementary volume descriptor */
703 				sec = NULL;
704 				}
705 			}
706 #endif
707 		} else {
708 			if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
709 				if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
710 					goto out_freebh;
711 
712 				sbi->s_high_sierra = 1;
713 				opt.rock = 0;
714 				h_pri = (struct hs_primary_descriptor *)vdp;
715 				goto root_found;
716 			}
717 		}
718 
719 		/* Just skip any volume descriptors we don't recognize */
720 
721 		brelse(bh);
722 		bh = NULL;
723 	}
724 	/*
725 	 * If we fall through, either no volume descriptor was found,
726 	 * or else we passed a primary descriptor looking for others.
727 	 */
728 	if (!pri)
729 		goto out_unknown_format;
730 	brelse(bh);
731 	bh = pri_bh;
732 	pri_bh = NULL;
733 
734 root_found:
735 	/* We don't support read-write mounts */
736 	if (!(s->s_flags & MS_RDONLY)) {
737 		error = -EACCES;
738 		goto out_freebh;
739 	}
740 
741 	if (joliet_level && (pri == NULL || !opt.rock)) {
742 		/* This is the case of Joliet with the norock mount flag.
743 		 * A disc with both Joliet and Rock Ridge is handled later
744 		 */
745 		pri = (struct iso_primary_descriptor *) sec;
746 	}
747 
748 	if(sbi->s_high_sierra){
749 		rootp = (struct iso_directory_record *) h_pri->root_directory_record;
750 		sbi->s_nzones = isonum_733(h_pri->volume_space_size);
751 		sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
752 		sbi->s_max_size = isonum_733(h_pri->volume_space_size);
753 	} else {
754 		if (!pri)
755 			goto out_freebh;
756 		rootp = (struct iso_directory_record *) pri->root_directory_record;
757 		sbi->s_nzones = isonum_733(pri->volume_space_size);
758 		sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
759 		sbi->s_max_size = isonum_733(pri->volume_space_size);
760 	}
761 
762 	sbi->s_ninodes = 0; /* No way to figure this out easily */
763 
764 	orig_zonesize = sbi->s_log_zone_size;
765 	/*
766 	 * If the zone size is smaller than the hardware sector size,
767 	 * this is a fatal error.  This would occur if the disc drive
768 	 * had sectors that were 2048 bytes, but the filesystem had
769 	 * blocks that were 512 bytes (which should only very rarely
770 	 * happen.)
771 	 */
772 	if (orig_zonesize < opt.blocksize)
773 		goto out_bad_size;
774 
775 	/* RDE: convert log zone size to bit shift */
776 	switch (sbi->s_log_zone_size) {
777 	case  512: sbi->s_log_zone_size =  9; break;
778 	case 1024: sbi->s_log_zone_size = 10; break;
779 	case 2048: sbi->s_log_zone_size = 11; break;
780 
781 	default:
782 		goto out_bad_zone_size;
783 	}
784 
785 	s->s_magic = ISOFS_SUPER_MAGIC;
786 
787 	/*
788 	 * With multi-extent files, file size is only limited by the maximum
789 	 * size of a file system, which is 8 TB.
790 	 */
791 	s->s_maxbytes = 0x80000000000LL;
792 
793 	/* Set this for reference. Its not currently used except on write
794 	   which we don't have .. */
795 
796 	first_data_zone = isonum_733(rootp->extent) +
797 			  isonum_711(rootp->ext_attr_length);
798 	sbi->s_firstdatazone = first_data_zone;
799 #ifndef BEQUIET
800 	printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
801 		sbi->s_max_size, 1UL << sbi->s_log_zone_size);
802 	printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
803 	if(sbi->s_high_sierra)
804 		printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
805 #endif
806 
807 	/*
808 	 * If the Joliet level is set, we _may_ decide to use the
809 	 * secondary descriptor, but can't be sure until after we
810 	 * read the root inode. But before reading the root inode
811 	 * we may need to change the device blocksize, and would
812 	 * rather release the old buffer first. So, we cache the
813 	 * first_data_zone value from the secondary descriptor.
814 	 */
815 	if (joliet_level) {
816 		pri = (struct iso_primary_descriptor *) sec;
817 		rootp = (struct iso_directory_record *)
818 			pri->root_directory_record;
819 		first_data_zone = isonum_733(rootp->extent) +
820 				isonum_711(rootp->ext_attr_length);
821 	}
822 
823 	/*
824 	 * We're all done using the volume descriptor, and may need
825 	 * to change the device blocksize, so release the buffer now.
826 	 */
827 	brelse(pri_bh);
828 	brelse(bh);
829 
830 	/*
831 	 * Force the blocksize to 512 for 512 byte sectors.  The file
832 	 * read primitives really get it wrong in a bad way if we don't
833 	 * do this.
834 	 *
835 	 * Note - we should never be setting the blocksize to something
836 	 * less than the hardware sector size for the device.  If we
837 	 * do, we would end up having to read larger buffers and split
838 	 * out portions to satisfy requests.
839 	 *
840 	 * Note2- the idea here is that we want to deal with the optimal
841 	 * zonesize in the filesystem.  If we have it set to something less,
842 	 * then we have horrible problems with trying to piece together
843 	 * bits of adjacent blocks in order to properly read directory
844 	 * entries.  By forcing the blocksize in this way, we ensure
845 	 * that we will never be required to do this.
846 	 */
847 	sb_set_blocksize(s, orig_zonesize);
848 
849 	sbi->s_nls_iocharset = NULL;
850 
851 #ifdef CONFIG_JOLIET
852 	if (joliet_level && opt.utf8 == 0) {
853 		char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
854 		sbi->s_nls_iocharset = load_nls(p);
855 		if (! sbi->s_nls_iocharset) {
856 			/* Fail only if explicit charset specified */
857 			if (opt.iocharset)
858 				goto out_freesbi;
859 			sbi->s_nls_iocharset = load_nls_default();
860 		}
861 	}
862 #endif
863 	s->s_op = &isofs_sops;
864 	s->s_export_op = &isofs_export_ops;
865 	sbi->s_mapping = opt.map;
866 	sbi->s_rock = (opt.rock ? 2 : 0);
867 	sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
868 	sbi->s_cruft = opt.cruft;
869 	sbi->s_hide = opt.hide;
870 	sbi->s_showassoc = opt.showassoc;
871 	sbi->s_uid = opt.uid;
872 	sbi->s_gid = opt.gid;
873 	sbi->s_uid_set = opt.uid_set;
874 	sbi->s_gid_set = opt.gid_set;
875 	sbi->s_utf8 = opt.utf8;
876 	sbi->s_nocompress = opt.nocompress;
877 	sbi->s_overriderockperm = opt.overriderockperm;
878 	/*
879 	 * It would be incredibly stupid to allow people to mark every file
880 	 * on the disk as suid, so we merely allow them to set the default
881 	 * permissions.
882 	 */
883 	if (opt.fmode != ISOFS_INVALID_MODE)
884 		sbi->s_fmode = opt.fmode & 0777;
885 	else
886 		sbi->s_fmode = ISOFS_INVALID_MODE;
887 	if (opt.dmode != ISOFS_INVALID_MODE)
888 		sbi->s_dmode = opt.dmode & 0777;
889 	else
890 		sbi->s_dmode = ISOFS_INVALID_MODE;
891 
892 	/*
893 	 * Read the root inode, which _may_ result in changing
894 	 * the s_rock flag. Once we have the final s_rock value,
895 	 * we then decide whether to use the Joliet descriptor.
896 	 */
897 	inode = isofs_iget(s, sbi->s_firstdatazone, 0);
898 	if (IS_ERR(inode))
899 		goto out_no_root;
900 
901 	/*
902 	 * Fix for broken CDs with Rock Ridge and empty ISO root directory but
903 	 * correct Joliet root directory.
904 	 */
905 	if (sbi->s_rock == 1 && joliet_level &&
906 				rootdir_empty(s, sbi->s_firstdatazone)) {
907 		printk(KERN_NOTICE
908 			"ISOFS: primary root directory is empty. "
909 			"Disabling Rock Ridge and switching to Joliet.");
910 		sbi->s_rock = 0;
911 	}
912 
913 	/*
914 	 * If this disk has both Rock Ridge and Joliet on it, then we
915 	 * want to use Rock Ridge by default.  This can be overridden
916 	 * by using the norock mount option.  There is still one other
917 	 * possibility that is not taken into account: a Rock Ridge
918 	 * CD with Unicode names.  Until someone sees such a beast, it
919 	 * will not be supported.
920 	 */
921 	if (sbi->s_rock == 1) {
922 		joliet_level = 0;
923 	} else if (joliet_level) {
924 		sbi->s_rock = 0;
925 		if (sbi->s_firstdatazone != first_data_zone) {
926 			sbi->s_firstdatazone = first_data_zone;
927 			printk(KERN_DEBUG
928 				"ISOFS: changing to secondary root\n");
929 			iput(inode);
930 			inode = isofs_iget(s, sbi->s_firstdatazone, 0);
931 			if (IS_ERR(inode))
932 				goto out_no_root;
933 		}
934 	}
935 
936 	if (opt.check == 'u') {
937 		/* Only Joliet is case insensitive by default */
938 		if (joliet_level)
939 			opt.check = 'r';
940 		else
941 			opt.check = 's';
942 	}
943 	sbi->s_joliet_level = joliet_level;
944 
945 	/* Make sure the root inode is a directory */
946 	if (!S_ISDIR(inode->i_mode)) {
947 		printk(KERN_WARNING
948 			"isofs_fill_super: root inode is not a directory. "
949 			"Corrupted media?\n");
950 		goto out_iput;
951 	}
952 
953 	table = 0;
954 	if (joliet_level)
955 		table += 2;
956 	if (opt.check == 'r')
957 		table++;
958 	sbi->s_check = opt.check;
959 
960 	if (table)
961 		s->s_d_op = &isofs_dentry_ops[table - 1];
962 
963 	/* get the root dentry */
964 	s->s_root = d_make_root(inode);
965 	if (!(s->s_root)) {
966 		error = -ENOMEM;
967 		goto out_no_inode;
968 	}
969 
970 	kfree(opt.iocharset);
971 
972 	return 0;
973 
974 	/*
975 	 * Display error messages and free resources.
976 	 */
977 out_iput:
978 	iput(inode);
979 	goto out_no_inode;
980 out_no_root:
981 	error = PTR_ERR(inode);
982 	if (error != -ENOMEM)
983 		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
984 out_no_inode:
985 #ifdef CONFIG_JOLIET
986 	unload_nls(sbi->s_nls_iocharset);
987 #endif
988 	goto out_freesbi;
989 out_no_read:
990 	printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
991 		__func__, s->s_id, iso_blknum, block);
992 	goto out_freebh;
993 out_bad_zone_size:
994 	printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
995 		sbi->s_log_zone_size);
996 	goto out_freebh;
997 out_bad_size:
998 	printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
999 		orig_zonesize, opt.blocksize);
1000 	goto out_freebh;
1001 out_unknown_format:
1002 	if (!silent)
1003 		printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
1004 
1005 out_freebh:
1006 	brelse(bh);
1007 	brelse(pri_bh);
1008 out_freesbi:
1009 	kfree(opt.iocharset);
1010 	kfree(sbi);
1011 	s->s_fs_info = NULL;
1012 	return error;
1013 }
1014 
1015 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
1016 {
1017 	struct super_block *sb = dentry->d_sb;
1018 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1019 
1020 	buf->f_type = ISOFS_SUPER_MAGIC;
1021 	buf->f_bsize = sb->s_blocksize;
1022 	buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1023 		<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1024 	buf->f_bfree = 0;
1025 	buf->f_bavail = 0;
1026 	buf->f_files = ISOFS_SB(sb)->s_ninodes;
1027 	buf->f_ffree = 0;
1028 	buf->f_fsid.val[0] = (u32)id;
1029 	buf->f_fsid.val[1] = (u32)(id >> 32);
1030 	buf->f_namelen = NAME_MAX;
1031 	return 0;
1032 }
1033 
1034 /*
1035  * Get a set of blocks; filling in buffer_heads if already allocated
1036  * or getblk() if they are not.  Returns the number of blocks inserted
1037  * (-ve == error.)
1038  */
1039 int isofs_get_blocks(struct inode *inode, sector_t iblock,
1040 		     struct buffer_head **bh, unsigned long nblocks)
1041 {
1042 	unsigned long b_off = iblock;
1043 	unsigned offset, sect_size;
1044 	unsigned int firstext;
1045 	unsigned long nextblk, nextoff;
1046 	int section, rv, error;
1047 	struct iso_inode_info *ei = ISOFS_I(inode);
1048 
1049 	error = -EIO;
1050 	rv = 0;
1051 	if (iblock != b_off) {
1052 		printk(KERN_DEBUG "%s: block number too large\n", __func__);
1053 		goto abort;
1054 	}
1055 
1056 
1057 	offset = 0;
1058 	firstext = ei->i_first_extent;
1059 	sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1060 	nextblk = ei->i_next_section_block;
1061 	nextoff = ei->i_next_section_offset;
1062 	section = 0;
1063 
1064 	while (nblocks) {
1065 		/* If we are *way* beyond the end of the file, print a message.
1066 		 * Access beyond the end of the file up to the next page boundary
1067 		 * is normal, however because of the way the page cache works.
1068 		 * In this case, we just return 0 so that we can properly fill
1069 		 * the page with useless information without generating any
1070 		 * I/O errors.
1071 		 */
1072 		if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1073 			printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1074 				__func__, b_off,
1075 				(unsigned long long)inode->i_size);
1076 			goto abort;
1077 		}
1078 
1079 		/* On the last section, nextblk == 0, section size is likely to
1080 		 * exceed sect_size by a partial block, and access beyond the
1081 		 * end of the file will reach beyond the section size, too.
1082 		 */
1083 		while (nextblk && (b_off >= (offset + sect_size))) {
1084 			struct inode *ninode;
1085 
1086 			offset += sect_size;
1087 			ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1088 			if (IS_ERR(ninode)) {
1089 				error = PTR_ERR(ninode);
1090 				goto abort;
1091 			}
1092 			firstext  = ISOFS_I(ninode)->i_first_extent;
1093 			sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1094 			nextblk   = ISOFS_I(ninode)->i_next_section_block;
1095 			nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1096 			iput(ninode);
1097 
1098 			if (++section > 100) {
1099 				printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1100 					" aborting...\n", __func__);
1101 				printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1102 					"nextblk=%lu nextoff=%lu\n", __func__,
1103 					b_off, firstext, (unsigned) sect_size,
1104 					nextblk, nextoff);
1105 				goto abort;
1106 			}
1107 		}
1108 
1109 		if (*bh) {
1110 			map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1111 		} else {
1112 			*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1113 			if (!*bh)
1114 				goto abort;
1115 		}
1116 		bh++;	/* Next buffer head */
1117 		b_off++;	/* Next buffer offset */
1118 		nblocks--;
1119 		rv++;
1120 	}
1121 
1122 	error = 0;
1123 abort:
1124 	return rv != 0 ? rv : error;
1125 }
1126 
1127 /*
1128  * Used by the standard interfaces.
1129  */
1130 static int isofs_get_block(struct inode *inode, sector_t iblock,
1131 		    struct buffer_head *bh_result, int create)
1132 {
1133 	int ret;
1134 
1135 	if (create) {
1136 		printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1137 		return -EROFS;
1138 	}
1139 
1140 	ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1141 	return ret < 0 ? ret : 0;
1142 }
1143 
1144 static int isofs_bmap(struct inode *inode, sector_t block)
1145 {
1146 	struct buffer_head dummy;
1147 	int error;
1148 
1149 	dummy.b_state = 0;
1150 	dummy.b_blocknr = -1000;
1151 	error = isofs_get_block(inode, block, &dummy, 0);
1152 	if (!error)
1153 		return dummy.b_blocknr;
1154 	return 0;
1155 }
1156 
1157 struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1158 {
1159 	sector_t blknr = isofs_bmap(inode, block);
1160 	if (!blknr)
1161 		return NULL;
1162 	return sb_bread(inode->i_sb, blknr);
1163 }
1164 
1165 static int isofs_readpage(struct file *file, struct page *page)
1166 {
1167 	return mpage_readpage(page, isofs_get_block);
1168 }
1169 
1170 static int isofs_readpages(struct file *file, struct address_space *mapping,
1171 			struct list_head *pages, unsigned nr_pages)
1172 {
1173 	return mpage_readpages(mapping, pages, nr_pages, isofs_get_block);
1174 }
1175 
1176 static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1177 {
1178 	return generic_block_bmap(mapping,block,isofs_get_block);
1179 }
1180 
1181 static const struct address_space_operations isofs_aops = {
1182 	.readpage = isofs_readpage,
1183 	.readpages = isofs_readpages,
1184 	.bmap = _isofs_bmap
1185 };
1186 
1187 static int isofs_read_level3_size(struct inode *inode)
1188 {
1189 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1190 	int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1191 	struct buffer_head *bh = NULL;
1192 	unsigned long block, offset, block_saved, offset_saved;
1193 	int i = 0;
1194 	int more_entries = 0;
1195 	struct iso_directory_record *tmpde = NULL;
1196 	struct iso_inode_info *ei = ISOFS_I(inode);
1197 
1198 	inode->i_size = 0;
1199 
1200 	/* The first 16 blocks are reserved as the System Area.  Thus,
1201 	 * no inodes can appear in block 0.  We use this to flag that
1202 	 * this is the last section. */
1203 	ei->i_next_section_block = 0;
1204 	ei->i_next_section_offset = 0;
1205 
1206 	block = ei->i_iget5_block;
1207 	offset = ei->i_iget5_offset;
1208 
1209 	do {
1210 		struct iso_directory_record *de;
1211 		unsigned int de_len;
1212 
1213 		if (!bh) {
1214 			bh = sb_bread(inode->i_sb, block);
1215 			if (!bh)
1216 				goto out_noread;
1217 		}
1218 		de = (struct iso_directory_record *) (bh->b_data + offset);
1219 		de_len = *(unsigned char *) de;
1220 
1221 		if (de_len == 0) {
1222 			brelse(bh);
1223 			bh = NULL;
1224 			++block;
1225 			offset = 0;
1226 			continue;
1227 		}
1228 
1229 		block_saved = block;
1230 		offset_saved = offset;
1231 		offset += de_len;
1232 
1233 		/* Make sure we have a full directory entry */
1234 		if (offset >= bufsize) {
1235 			int slop = bufsize - offset + de_len;
1236 			if (!tmpde) {
1237 				tmpde = kmalloc(256, GFP_KERNEL);
1238 				if (!tmpde)
1239 					goto out_nomem;
1240 			}
1241 			memcpy(tmpde, de, slop);
1242 			offset &= bufsize - 1;
1243 			block++;
1244 			brelse(bh);
1245 			bh = NULL;
1246 			if (offset) {
1247 				bh = sb_bread(inode->i_sb, block);
1248 				if (!bh)
1249 					goto out_noread;
1250 				memcpy((void *)tmpde+slop, bh->b_data, offset);
1251 			}
1252 			de = tmpde;
1253 		}
1254 
1255 		inode->i_size += isonum_733(de->size);
1256 		if (i == 1) {
1257 			ei->i_next_section_block = block_saved;
1258 			ei->i_next_section_offset = offset_saved;
1259 		}
1260 
1261 		more_entries = de->flags[-high_sierra] & 0x80;
1262 
1263 		i++;
1264 		if (i > 100)
1265 			goto out_toomany;
1266 	} while (more_entries);
1267 out:
1268 	kfree(tmpde);
1269 	if (bh)
1270 		brelse(bh);
1271 	return 0;
1272 
1273 out_nomem:
1274 	if (bh)
1275 		brelse(bh);
1276 	return -ENOMEM;
1277 
1278 out_noread:
1279 	printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1280 	kfree(tmpde);
1281 	return -EIO;
1282 
1283 out_toomany:
1284 	printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1285 		"isofs_read_level3_size: inode=%lu\n",
1286 		__func__, inode->i_ino);
1287 	goto out;
1288 }
1289 
1290 static int isofs_read_inode(struct inode *inode, int relocated)
1291 {
1292 	struct super_block *sb = inode->i_sb;
1293 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
1294 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1295 	unsigned long block;
1296 	int high_sierra = sbi->s_high_sierra;
1297 	struct buffer_head *bh = NULL;
1298 	struct iso_directory_record *de;
1299 	struct iso_directory_record *tmpde = NULL;
1300 	unsigned int de_len;
1301 	unsigned long offset;
1302 	struct iso_inode_info *ei = ISOFS_I(inode);
1303 	int ret = -EIO;
1304 
1305 	block = ei->i_iget5_block;
1306 	bh = sb_bread(inode->i_sb, block);
1307 	if (!bh)
1308 		goto out_badread;
1309 
1310 	offset = ei->i_iget5_offset;
1311 
1312 	de = (struct iso_directory_record *) (bh->b_data + offset);
1313 	de_len = *(unsigned char *) de;
1314 
1315 	if (offset + de_len > bufsize) {
1316 		int frag1 = bufsize - offset;
1317 
1318 		tmpde = kmalloc(de_len, GFP_KERNEL);
1319 		if (tmpde == NULL) {
1320 			printk(KERN_INFO "%s: out of memory\n", __func__);
1321 			ret = -ENOMEM;
1322 			goto fail;
1323 		}
1324 		memcpy(tmpde, bh->b_data + offset, frag1);
1325 		brelse(bh);
1326 		bh = sb_bread(inode->i_sb, ++block);
1327 		if (!bh)
1328 			goto out_badread;
1329 		memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1330 		de = tmpde;
1331 	}
1332 
1333 	inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1334 					ei->i_iget5_offset,
1335 					ISOFS_BUFFER_BITS(inode));
1336 
1337 	/* Assume it is a normal-format file unless told otherwise */
1338 	ei->i_file_format = isofs_file_normal;
1339 
1340 	if (de->flags[-high_sierra] & 2) {
1341 		if (sbi->s_dmode != ISOFS_INVALID_MODE)
1342 			inode->i_mode = S_IFDIR | sbi->s_dmode;
1343 		else
1344 			inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1345 		set_nlink(inode, 1);	/*
1346 					 * Set to 1.  We know there are 2, but
1347 					 * the find utility tries to optimize
1348 					 * if it is 2, and it screws up.  It is
1349 					 * easier to give 1 which tells find to
1350 					 * do it the hard way.
1351 					 */
1352 	} else {
1353 		if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1354 			inode->i_mode = S_IFREG | sbi->s_fmode;
1355 		} else {
1356 			/*
1357 			 * Set default permissions: r-x for all.  The disc
1358 			 * could be shared with DOS machines so virtually
1359 			 * anything could be a valid executable.
1360 			 */
1361 			inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1362 		}
1363 		set_nlink(inode, 1);
1364 	}
1365 	inode->i_uid = sbi->s_uid;
1366 	inode->i_gid = sbi->s_gid;
1367 	inode->i_blocks = 0;
1368 
1369 	ei->i_format_parm[0] = 0;
1370 	ei->i_format_parm[1] = 0;
1371 	ei->i_format_parm[2] = 0;
1372 
1373 	ei->i_section_size = isonum_733(de->size);
1374 	if (de->flags[-high_sierra] & 0x80) {
1375 		ret = isofs_read_level3_size(inode);
1376 		if (ret < 0)
1377 			goto fail;
1378 		ret = -EIO;
1379 	} else {
1380 		ei->i_next_section_block = 0;
1381 		ei->i_next_section_offset = 0;
1382 		inode->i_size = isonum_733(de->size);
1383 	}
1384 
1385 	/*
1386 	 * Some dipshit decided to store some other bit of information
1387 	 * in the high byte of the file length.  Truncate size in case
1388 	 * this CDROM was mounted with the cruft option.
1389 	 */
1390 
1391 	if (sbi->s_cruft)
1392 		inode->i_size &= 0x00ffffff;
1393 
1394 	if (de->interleave[0]) {
1395 		printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1396 		inode->i_size = 0;
1397 	}
1398 
1399 	/* I have no idea what file_unit_size is used for, so
1400 	   we will flag it for now */
1401 	if (de->file_unit_size[0] != 0) {
1402 		printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1403 			inode->i_ino);
1404 	}
1405 
1406 	/* I have no idea what other flag bits are used for, so
1407 	   we will flag it for now */
1408 #ifdef DEBUG
1409 	if((de->flags[-high_sierra] & ~2)!= 0){
1410 		printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1411 				"(%ld %x).\n",
1412 			inode->i_ino, de->flags[-high_sierra]);
1413 	}
1414 #endif
1415 
1416 	inode->i_mtime.tv_sec =
1417 	inode->i_atime.tv_sec =
1418 	inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
1419 	inode->i_mtime.tv_nsec =
1420 	inode->i_atime.tv_nsec =
1421 	inode->i_ctime.tv_nsec = 0;
1422 
1423 	ei->i_first_extent = (isonum_733(de->extent) +
1424 			isonum_711(de->ext_attr_length));
1425 
1426 	/* Set the number of blocks for stat() - should be done before RR */
1427 	inode->i_blocks = (inode->i_size + 511) >> 9;
1428 
1429 	/*
1430 	 * Now test for possible Rock Ridge extensions which will override
1431 	 * some of these numbers in the inode structure.
1432 	 */
1433 
1434 	if (!high_sierra) {
1435 		parse_rock_ridge_inode(de, inode, relocated);
1436 		/* if we want uid/gid set, override the rock ridge setting */
1437 		if (sbi->s_uid_set)
1438 			inode->i_uid = sbi->s_uid;
1439 		if (sbi->s_gid_set)
1440 			inode->i_gid = sbi->s_gid;
1441 	}
1442 	/* Now set final access rights if overriding rock ridge setting */
1443 	if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1444 	    sbi->s_dmode != ISOFS_INVALID_MODE)
1445 		inode->i_mode = S_IFDIR | sbi->s_dmode;
1446 	if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1447 	    sbi->s_fmode != ISOFS_INVALID_MODE)
1448 		inode->i_mode = S_IFREG | sbi->s_fmode;
1449 
1450 	/* Install the inode operations vector */
1451 	if (S_ISREG(inode->i_mode)) {
1452 		inode->i_fop = &generic_ro_fops;
1453 		switch (ei->i_file_format) {
1454 #ifdef CONFIG_ZISOFS
1455 		case isofs_file_compressed:
1456 			inode->i_data.a_ops = &zisofs_aops;
1457 			break;
1458 #endif
1459 		default:
1460 			inode->i_data.a_ops = &isofs_aops;
1461 			break;
1462 		}
1463 	} else if (S_ISDIR(inode->i_mode)) {
1464 		inode->i_op = &isofs_dir_inode_operations;
1465 		inode->i_fop = &isofs_dir_operations;
1466 	} else if (S_ISLNK(inode->i_mode)) {
1467 		inode->i_op = &page_symlink_inode_operations;
1468 		inode_nohighmem(inode);
1469 		inode->i_data.a_ops = &isofs_symlink_aops;
1470 	} else
1471 		/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1472 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1473 
1474 	ret = 0;
1475 out:
1476 	kfree(tmpde);
1477 	if (bh)
1478 		brelse(bh);
1479 	return ret;
1480 
1481 out_badread:
1482 	printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1483 fail:
1484 	goto out;
1485 }
1486 
1487 struct isofs_iget5_callback_data {
1488 	unsigned long block;
1489 	unsigned long offset;
1490 };
1491 
1492 static int isofs_iget5_test(struct inode *ino, void *data)
1493 {
1494 	struct iso_inode_info *i = ISOFS_I(ino);
1495 	struct isofs_iget5_callback_data *d =
1496 		(struct isofs_iget5_callback_data*)data;
1497 	return (i->i_iget5_block == d->block)
1498 		&& (i->i_iget5_offset == d->offset);
1499 }
1500 
1501 static int isofs_iget5_set(struct inode *ino, void *data)
1502 {
1503 	struct iso_inode_info *i = ISOFS_I(ino);
1504 	struct isofs_iget5_callback_data *d =
1505 		(struct isofs_iget5_callback_data*)data;
1506 	i->i_iget5_block = d->block;
1507 	i->i_iget5_offset = d->offset;
1508 	return 0;
1509 }
1510 
1511 /* Store, in the inode's containing structure, the block and block
1512  * offset that point to the underlying meta-data for the inode.  The
1513  * code below is otherwise similar to the iget() code in
1514  * include/linux/fs.h */
1515 struct inode *__isofs_iget(struct super_block *sb,
1516 			   unsigned long block,
1517 			   unsigned long offset,
1518 			   int relocated)
1519 {
1520 	unsigned long hashval;
1521 	struct inode *inode;
1522 	struct isofs_iget5_callback_data data;
1523 	long ret;
1524 
1525 	if (offset >= 1ul << sb->s_blocksize_bits)
1526 		return ERR_PTR(-EINVAL);
1527 
1528 	data.block = block;
1529 	data.offset = offset;
1530 
1531 	hashval = (block << sb->s_blocksize_bits) | offset;
1532 
1533 	inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1534 				&isofs_iget5_set, &data);
1535 
1536 	if (!inode)
1537 		return ERR_PTR(-ENOMEM);
1538 
1539 	if (inode->i_state & I_NEW) {
1540 		ret = isofs_read_inode(inode, relocated);
1541 		if (ret < 0) {
1542 			iget_failed(inode);
1543 			inode = ERR_PTR(ret);
1544 		} else {
1545 			unlock_new_inode(inode);
1546 		}
1547 	}
1548 
1549 	return inode;
1550 }
1551 
1552 static struct dentry *isofs_mount(struct file_system_type *fs_type,
1553 	int flags, const char *dev_name, void *data)
1554 {
1555 	return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1556 }
1557 
1558 static struct file_system_type iso9660_fs_type = {
1559 	.owner		= THIS_MODULE,
1560 	.name		= "iso9660",
1561 	.mount		= isofs_mount,
1562 	.kill_sb	= kill_block_super,
1563 	.fs_flags	= FS_REQUIRES_DEV,
1564 };
1565 MODULE_ALIAS_FS("iso9660");
1566 MODULE_ALIAS("iso9660");
1567 
1568 static int __init init_iso9660_fs(void)
1569 {
1570 	int err = init_inodecache();
1571 	if (err)
1572 		goto out;
1573 #ifdef CONFIG_ZISOFS
1574 	err = zisofs_init();
1575 	if (err)
1576 		goto out1;
1577 #endif
1578 	err = register_filesystem(&iso9660_fs_type);
1579 	if (err)
1580 		goto out2;
1581 	return 0;
1582 out2:
1583 #ifdef CONFIG_ZISOFS
1584 	zisofs_cleanup();
1585 out1:
1586 #endif
1587 	destroy_inodecache();
1588 out:
1589 	return err;
1590 }
1591 
1592 static void __exit exit_iso9660_fs(void)
1593 {
1594         unregister_filesystem(&iso9660_fs_type);
1595 #ifdef CONFIG_ZISOFS
1596 	zisofs_cleanup();
1597 #endif
1598 	destroy_inodecache();
1599 }
1600 
1601 module_init(init_iso9660_fs)
1602 module_exit(exit_iso9660_fs)
1603 MODULE_LICENSE("GPL");
1604