xref: /linux/fs/isofs/inode.c (revision 5bdd5fbb35ab0fe21bf2263106f51c5bee466a07)
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)
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 & SB_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 			kfree(popt->iocharset);
398 			popt->iocharset = match_strdup(&args[0]);
399 			if (!popt->iocharset)
400 				return 0;
401 			break;
402 #endif
403 		case Opt_map_a:
404 			popt->map = 'a';
405 			break;
406 		case Opt_map_o:
407 			popt->map = 'o';
408 			break;
409 		case Opt_map_n:
410 			popt->map = 'n';
411 			break;
412 		case Opt_session:
413 			if (match_int(&args[0], &option))
414 				return 0;
415 			n = option;
416 			/*
417 			 * Track numbers are supposed to be in range 1-99, the
418 			 * mount option starts indexing at 0.
419 			 */
420 			if (n >= 99)
421 				return 0;
422 			popt->session = n + 1;
423 			break;
424 		case Opt_sb:
425 			if (match_int(&args[0], &option))
426 				return 0;
427 			popt->sbsector = option;
428 			break;
429 		case Opt_check_r:
430 			popt->check = 'r';
431 			break;
432 		case Opt_check_s:
433 			popt->check = 's';
434 			break;
435 		case Opt_ignore:
436 			break;
437 		case Opt_uid:
438 			if (match_int(&args[0], &option))
439 				return 0;
440 			popt->uid = make_kuid(current_user_ns(), option);
441 			if (!uid_valid(popt->uid))
442 				return 0;
443 			popt->uid_set = 1;
444 			break;
445 		case Opt_gid:
446 			if (match_int(&args[0], &option))
447 				return 0;
448 			popt->gid = make_kgid(current_user_ns(), option);
449 			if (!gid_valid(popt->gid))
450 				return 0;
451 			popt->gid_set = 1;
452 			break;
453 		case Opt_mode:
454 			if (match_int(&args[0], &option))
455 				return 0;
456 			popt->fmode = option;
457 			break;
458 		case Opt_dmode:
459 			if (match_int(&args[0], &option))
460 				return 0;
461 			popt->dmode = option;
462 			break;
463 		case Opt_overriderockperm:
464 			popt->overriderockperm = 1;
465 			break;
466 		case Opt_block:
467 			if (match_int(&args[0], &option))
468 				return 0;
469 			n = option;
470 			if (n != 512 && n != 1024 && n != 2048)
471 				return 0;
472 			popt->blocksize = n;
473 			break;
474 		case Opt_nocompress:
475 			popt->nocompress = 1;
476 			break;
477 		default:
478 			return 0;
479 		}
480 	}
481 	return 1;
482 }
483 
484 /*
485  * Display the mount options in /proc/mounts.
486  */
487 static int isofs_show_options(struct seq_file *m, struct dentry *root)
488 {
489 	struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
490 
491 	if (!sbi->s_rock)		seq_puts(m, ",norock");
492 	else if (!sbi->s_joliet_level)	seq_puts(m, ",nojoliet");
493 	if (sbi->s_cruft)		seq_puts(m, ",cruft");
494 	if (sbi->s_hide)		seq_puts(m, ",hide");
495 	if (sbi->s_nocompress)		seq_puts(m, ",nocompress");
496 	if (sbi->s_overriderockperm)	seq_puts(m, ",overriderockperm");
497 	if (sbi->s_showassoc)		seq_puts(m, ",showassoc");
498 	if (sbi->s_utf8)		seq_puts(m, ",utf8");
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 	    strcmp(sbi->s_nls_iocharset->charset, CONFIG_NLS_DEFAULT) != 0)
523 		seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
524 #endif
525 	return 0;
526 }
527 
528 /*
529  * look if the driver can tell the multi session redirection value
530  *
531  * don't change this if you don't know what you do, please!
532  * Multisession is legal only with XA disks.
533  * A non-XA disk with more than one volume descriptor may do it right, but
534  * usually is written in a nowhere standardized "multi-partition" manner.
535  * Multisession uses absolute addressing (solely the first frame of the whole
536  * track is #0), multi-partition uses relative addressing (each first frame of
537  * each track is #0), and a track is not a session.
538  *
539  * A broken CDwriter software or drive firmware does not set new standards,
540  * at least not if conflicting with the existing ones.
541  *
542  * emoenke@gwdg.de
543  */
544 #define WE_OBEY_THE_WRITTEN_STANDARDS 1
545 
546 static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
547 {
548 	struct cdrom_multisession ms_info;
549 	unsigned int vol_desc_start;
550 	struct block_device *bdev = sb->s_bdev;
551 	int i;
552 
553 	vol_desc_start=0;
554 	ms_info.addr_format=CDROM_LBA;
555 	if (session > 0) {
556 		struct cdrom_tocentry Te;
557 		Te.cdte_track=session;
558 		Te.cdte_format=CDROM_LBA;
559 		i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
560 		if (!i) {
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 	i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long) &ms_info);
571 	if (session > 0)
572 		printk(KERN_ERR "ISOFS: Invalid session number\n");
573 #if 0
574 	printk(KERN_DEBUG "isofs.inode: CDROMMULTISESSION: rc=%d\n",i);
575 	if (i==0) {
576 		printk(KERN_DEBUG "isofs.inode: XA disk: %s\n",ms_info.xa_flag?"yes":"no");
577 		printk(KERN_DEBUG "isofs.inode: vol_desc_start = %d\n", ms_info.addr.lba);
578 	}
579 #endif
580 	if (i==0)
581 #if WE_OBEY_THE_WRITTEN_STANDARDS
582 		if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
583 #endif
584 			vol_desc_start=ms_info.addr.lba;
585 	return vol_desc_start;
586 }
587 
588 /*
589  * Check if root directory is empty (has less than 3 files).
590  *
591  * Used to detect broken CDs where ISO root directory is empty but Joliet root
592  * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
593  * (and Joliet used instead) or else no files would be visible.
594  */
595 static bool rootdir_empty(struct super_block *sb, unsigned long block)
596 {
597 	int offset = 0, files = 0, de_len;
598 	struct iso_directory_record *de;
599 	struct buffer_head *bh;
600 
601 	bh = sb_bread(sb, block);
602 	if (!bh)
603 		return true;
604 	while (files < 3) {
605 		de = (struct iso_directory_record *) (bh->b_data + offset);
606 		de_len = *(unsigned char *) de;
607 		if (de_len == 0)
608 			break;
609 		files++;
610 		offset += de_len;
611 	}
612 	brelse(bh);
613 	return files < 3;
614 }
615 
616 /*
617  * Initialize the superblock and read the root inode.
618  *
619  * Note: a check_disk_change() has been done immediately prior
620  * to this call, so we don't need to check again.
621  */
622 static int isofs_fill_super(struct super_block *s, void *data, int silent)
623 {
624 	struct buffer_head *bh = NULL, *pri_bh = NULL;
625 	struct hs_primary_descriptor *h_pri = NULL;
626 	struct iso_primary_descriptor *pri = NULL;
627 	struct iso_supplementary_descriptor *sec = NULL;
628 	struct iso_directory_record *rootp;
629 	struct inode *inode;
630 	struct iso9660_options opt;
631 	struct isofs_sb_info *sbi;
632 	unsigned long first_data_zone;
633 	int joliet_level = 0;
634 	int iso_blknum, block;
635 	int orig_zonesize;
636 	int table, error = -EINVAL;
637 	unsigned int vol_desc_start;
638 
639 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
640 	if (!sbi)
641 		return -ENOMEM;
642 	s->s_fs_info = sbi;
643 
644 	if (!parse_options((char *)data, &opt))
645 		goto out_freesbi;
646 
647 	/*
648 	 * First of all, get the hardware blocksize for this device.
649 	 * If we don't know what it is, or the hardware blocksize is
650 	 * larger than the blocksize the user specified, then use
651 	 * that value.
652 	 */
653 	/*
654 	 * What if bugger tells us to go beyond page size?
655 	 */
656 	opt.blocksize = sb_min_blocksize(s, opt.blocksize);
657 
658 	sbi->s_high_sierra = 0; /* default is iso9660 */
659 	sbi->s_session = opt.session;
660 	sbi->s_sbsector = opt.sbsector;
661 
662 	vol_desc_start = (opt.sbsector != -1) ?
663 		opt.sbsector : isofs_get_last_session(s,opt.session);
664 
665 	for (iso_blknum = vol_desc_start+16;
666 		iso_blknum < vol_desc_start+100; iso_blknum++) {
667 		struct hs_volume_descriptor *hdp;
668 		struct iso_volume_descriptor  *vdp;
669 
670 		block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
671 		if (!(bh = sb_bread(s, block)))
672 			goto out_no_read;
673 
674 		vdp = (struct iso_volume_descriptor *)bh->b_data;
675 		hdp = (struct hs_volume_descriptor *)bh->b_data;
676 
677 		/*
678 		 * Due to the overlapping physical location of the descriptors,
679 		 * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
680 		 * proper identification in this case, we first check for ISO.
681 		 */
682 		if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
683 			if (isonum_711(vdp->type) == ISO_VD_END)
684 				break;
685 			if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
686 				if (!pri) {
687 					pri = (struct iso_primary_descriptor *)vdp;
688 					/* Save the buffer in case we need it ... */
689 					pri_bh = bh;
690 					bh = NULL;
691 				}
692 			}
693 #ifdef CONFIG_JOLIET
694 			else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
695 				sec = (struct iso_supplementary_descriptor *)vdp;
696 				if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
697 					if (opt.joliet) {
698 						if (sec->escape[2] == 0x40)
699 							joliet_level = 1;
700 						else if (sec->escape[2] == 0x43)
701 							joliet_level = 2;
702 						else if (sec->escape[2] == 0x45)
703 							joliet_level = 3;
704 
705 						printk(KERN_DEBUG "ISO 9660 Extensions: "
706 							"Microsoft Joliet Level %d\n",
707 							joliet_level);
708 					}
709 					goto root_found;
710 				} else {
711 				/* Unknown supplementary volume descriptor */
712 				sec = NULL;
713 				}
714 			}
715 #endif
716 		} else {
717 			if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
718 				if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
719 					goto out_freebh;
720 
721 				sbi->s_high_sierra = 1;
722 				opt.rock = 0;
723 				h_pri = (struct hs_primary_descriptor *)vdp;
724 				goto root_found;
725 			}
726 		}
727 
728 		/* Just skip any volume descriptors we don't recognize */
729 
730 		brelse(bh);
731 		bh = NULL;
732 	}
733 	/*
734 	 * If we fall through, either no volume descriptor was found,
735 	 * or else we passed a primary descriptor looking for others.
736 	 */
737 	if (!pri)
738 		goto out_unknown_format;
739 	brelse(bh);
740 	bh = pri_bh;
741 	pri_bh = NULL;
742 
743 root_found:
744 	/* We don't support read-write mounts */
745 	if (!sb_rdonly(s)) {
746 		error = -EACCES;
747 		goto out_freebh;
748 	}
749 
750 	if (joliet_level && (!pri || !opt.rock)) {
751 		/* This is the case of Joliet with the norock mount flag.
752 		 * A disc with both Joliet and Rock Ridge is handled later
753 		 */
754 		pri = (struct iso_primary_descriptor *) sec;
755 	}
756 
757 	if(sbi->s_high_sierra){
758 		rootp = (struct iso_directory_record *) h_pri->root_directory_record;
759 		sbi->s_nzones = isonum_733(h_pri->volume_space_size);
760 		sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
761 		sbi->s_max_size = isonum_733(h_pri->volume_space_size);
762 	} else {
763 		if (!pri)
764 			goto out_freebh;
765 		rootp = (struct iso_directory_record *) pri->root_directory_record;
766 		sbi->s_nzones = isonum_733(pri->volume_space_size);
767 		sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
768 		sbi->s_max_size = isonum_733(pri->volume_space_size);
769 	}
770 
771 	sbi->s_ninodes = 0; /* No way to figure this out easily */
772 
773 	orig_zonesize = sbi->s_log_zone_size;
774 	/*
775 	 * If the zone size is smaller than the hardware sector size,
776 	 * this is a fatal error.  This would occur if the disc drive
777 	 * had sectors that were 2048 bytes, but the filesystem had
778 	 * blocks that were 512 bytes (which should only very rarely
779 	 * happen.)
780 	 */
781 	if (orig_zonesize < opt.blocksize)
782 		goto out_bad_size;
783 
784 	/* RDE: convert log zone size to bit shift */
785 	switch (sbi->s_log_zone_size) {
786 	case  512: sbi->s_log_zone_size =  9; break;
787 	case 1024: sbi->s_log_zone_size = 10; break;
788 	case 2048: sbi->s_log_zone_size = 11; break;
789 
790 	default:
791 		goto out_bad_zone_size;
792 	}
793 
794 	s->s_magic = ISOFS_SUPER_MAGIC;
795 
796 	/*
797 	 * With multi-extent files, file size is only limited by the maximum
798 	 * size of a file system, which is 8 TB.
799 	 */
800 	s->s_maxbytes = 0x80000000000LL;
801 
802 	/* Set this for reference. Its not currently used except on write
803 	   which we don't have .. */
804 
805 	first_data_zone = isonum_733(rootp->extent) +
806 			  isonum_711(rootp->ext_attr_length);
807 	sbi->s_firstdatazone = first_data_zone;
808 #ifndef BEQUIET
809 	printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
810 		sbi->s_max_size, 1UL << sbi->s_log_zone_size);
811 	printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
812 	if(sbi->s_high_sierra)
813 		printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
814 #endif
815 
816 	/*
817 	 * If the Joliet level is set, we _may_ decide to use the
818 	 * secondary descriptor, but can't be sure until after we
819 	 * read the root inode. But before reading the root inode
820 	 * we may need to change the device blocksize, and would
821 	 * rather release the old buffer first. So, we cache the
822 	 * first_data_zone value from the secondary descriptor.
823 	 */
824 	if (joliet_level) {
825 		pri = (struct iso_primary_descriptor *) sec;
826 		rootp = (struct iso_directory_record *)
827 			pri->root_directory_record;
828 		first_data_zone = isonum_733(rootp->extent) +
829 				isonum_711(rootp->ext_attr_length);
830 	}
831 
832 	/*
833 	 * We're all done using the volume descriptor, and may need
834 	 * to change the device blocksize, so release the buffer now.
835 	 */
836 	brelse(pri_bh);
837 	brelse(bh);
838 
839 	/*
840 	 * Force the blocksize to 512 for 512 byte sectors.  The file
841 	 * read primitives really get it wrong in a bad way if we don't
842 	 * do this.
843 	 *
844 	 * Note - we should never be setting the blocksize to something
845 	 * less than the hardware sector size for the device.  If we
846 	 * do, we would end up having to read larger buffers and split
847 	 * out portions to satisfy requests.
848 	 *
849 	 * Note2- the idea here is that we want to deal with the optimal
850 	 * zonesize in the filesystem.  If we have it set to something less,
851 	 * then we have horrible problems with trying to piece together
852 	 * bits of adjacent blocks in order to properly read directory
853 	 * entries.  By forcing the blocksize in this way, we ensure
854 	 * that we will never be required to do this.
855 	 */
856 	sb_set_blocksize(s, orig_zonesize);
857 
858 	sbi->s_nls_iocharset = NULL;
859 
860 #ifdef CONFIG_JOLIET
861 	if (joliet_level && opt.utf8 == 0) {
862 		char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
863 		sbi->s_nls_iocharset = load_nls(p);
864 		if (! sbi->s_nls_iocharset) {
865 			/* Fail only if explicit charset specified */
866 			if (opt.iocharset)
867 				goto out_freesbi;
868 			sbi->s_nls_iocharset = load_nls_default();
869 		}
870 	}
871 #endif
872 	s->s_op = &isofs_sops;
873 	s->s_export_op = &isofs_export_ops;
874 	sbi->s_mapping = opt.map;
875 	sbi->s_rock = (opt.rock ? 2 : 0);
876 	sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
877 	sbi->s_cruft = opt.cruft;
878 	sbi->s_hide = opt.hide;
879 	sbi->s_showassoc = opt.showassoc;
880 	sbi->s_uid = opt.uid;
881 	sbi->s_gid = opt.gid;
882 	sbi->s_uid_set = opt.uid_set;
883 	sbi->s_gid_set = opt.gid_set;
884 	sbi->s_utf8 = opt.utf8;
885 	sbi->s_nocompress = opt.nocompress;
886 	sbi->s_overriderockperm = opt.overriderockperm;
887 	/*
888 	 * It would be incredibly stupid to allow people to mark every file
889 	 * on the disk as suid, so we merely allow them to set the default
890 	 * permissions.
891 	 */
892 	if (opt.fmode != ISOFS_INVALID_MODE)
893 		sbi->s_fmode = opt.fmode & 0777;
894 	else
895 		sbi->s_fmode = ISOFS_INVALID_MODE;
896 	if (opt.dmode != ISOFS_INVALID_MODE)
897 		sbi->s_dmode = opt.dmode & 0777;
898 	else
899 		sbi->s_dmode = ISOFS_INVALID_MODE;
900 
901 	/*
902 	 * Read the root inode, which _may_ result in changing
903 	 * the s_rock flag. Once we have the final s_rock value,
904 	 * we then decide whether to use the Joliet descriptor.
905 	 */
906 	inode = isofs_iget(s, sbi->s_firstdatazone, 0);
907 	if (IS_ERR(inode))
908 		goto out_no_root;
909 
910 	/*
911 	 * Fix for broken CDs with Rock Ridge and empty ISO root directory but
912 	 * correct Joliet root directory.
913 	 */
914 	if (sbi->s_rock == 1 && joliet_level &&
915 				rootdir_empty(s, sbi->s_firstdatazone)) {
916 		printk(KERN_NOTICE
917 			"ISOFS: primary root directory is empty. "
918 			"Disabling Rock Ridge and switching to Joliet.");
919 		sbi->s_rock = 0;
920 	}
921 
922 	/*
923 	 * If this disk has both Rock Ridge and Joliet on it, then we
924 	 * want to use Rock Ridge by default.  This can be overridden
925 	 * by using the norock mount option.  There is still one other
926 	 * possibility that is not taken into account: a Rock Ridge
927 	 * CD with Unicode names.  Until someone sees such a beast, it
928 	 * will not be supported.
929 	 */
930 	if (sbi->s_rock == 1) {
931 		joliet_level = 0;
932 	} else if (joliet_level) {
933 		sbi->s_rock = 0;
934 		if (sbi->s_firstdatazone != first_data_zone) {
935 			sbi->s_firstdatazone = first_data_zone;
936 			printk(KERN_DEBUG
937 				"ISOFS: changing to secondary root\n");
938 			iput(inode);
939 			inode = isofs_iget(s, sbi->s_firstdatazone, 0);
940 			if (IS_ERR(inode))
941 				goto out_no_root;
942 		}
943 	}
944 
945 	if (opt.check == 'u') {
946 		/* Only Joliet is case insensitive by default */
947 		if (joliet_level)
948 			opt.check = 'r';
949 		else
950 			opt.check = 's';
951 	}
952 	sbi->s_joliet_level = joliet_level;
953 
954 	/* Make sure the root inode is a directory */
955 	if (!S_ISDIR(inode->i_mode)) {
956 		printk(KERN_WARNING
957 			"isofs_fill_super: root inode is not a directory. "
958 			"Corrupted media?\n");
959 		goto out_iput;
960 	}
961 
962 	table = 0;
963 	if (joliet_level)
964 		table += 2;
965 	if (opt.check == 'r')
966 		table++;
967 	sbi->s_check = opt.check;
968 
969 	if (table)
970 		s->s_d_op = &isofs_dentry_ops[table - 1];
971 
972 	/* get the root dentry */
973 	s->s_root = d_make_root(inode);
974 	if (!(s->s_root)) {
975 		error = -ENOMEM;
976 		goto out_no_inode;
977 	}
978 
979 	kfree(opt.iocharset);
980 
981 	return 0;
982 
983 	/*
984 	 * Display error messages and free resources.
985 	 */
986 out_iput:
987 	iput(inode);
988 	goto out_no_inode;
989 out_no_root:
990 	error = PTR_ERR(inode);
991 	if (error != -ENOMEM)
992 		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
993 out_no_inode:
994 #ifdef CONFIG_JOLIET
995 	unload_nls(sbi->s_nls_iocharset);
996 #endif
997 	goto out_freesbi;
998 out_no_read:
999 	printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
1000 		__func__, s->s_id, iso_blknum, block);
1001 	goto out_freebh;
1002 out_bad_zone_size:
1003 	printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
1004 		sbi->s_log_zone_size);
1005 	goto out_freebh;
1006 out_bad_size:
1007 	printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
1008 		orig_zonesize, opt.blocksize);
1009 	goto out_freebh;
1010 out_unknown_format:
1011 	if (!silent)
1012 		printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
1013 
1014 out_freebh:
1015 	brelse(bh);
1016 	brelse(pri_bh);
1017 out_freesbi:
1018 	kfree(opt.iocharset);
1019 	kfree(sbi);
1020 	s->s_fs_info = NULL;
1021 	return error;
1022 }
1023 
1024 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
1025 {
1026 	struct super_block *sb = dentry->d_sb;
1027 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1028 
1029 	buf->f_type = ISOFS_SUPER_MAGIC;
1030 	buf->f_bsize = sb->s_blocksize;
1031 	buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1032 		<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1033 	buf->f_bfree = 0;
1034 	buf->f_bavail = 0;
1035 	buf->f_files = ISOFS_SB(sb)->s_ninodes;
1036 	buf->f_ffree = 0;
1037 	buf->f_fsid.val[0] = (u32)id;
1038 	buf->f_fsid.val[1] = (u32)(id >> 32);
1039 	buf->f_namelen = NAME_MAX;
1040 	return 0;
1041 }
1042 
1043 /*
1044  * Get a set of blocks; filling in buffer_heads if already allocated
1045  * or getblk() if they are not.  Returns the number of blocks inserted
1046  * (-ve == error.)
1047  */
1048 int isofs_get_blocks(struct inode *inode, sector_t iblock,
1049 		     struct buffer_head **bh, unsigned long nblocks)
1050 {
1051 	unsigned long b_off = iblock;
1052 	unsigned offset, sect_size;
1053 	unsigned int firstext;
1054 	unsigned long nextblk, nextoff;
1055 	int section, rv, error;
1056 	struct iso_inode_info *ei = ISOFS_I(inode);
1057 
1058 	error = -EIO;
1059 	rv = 0;
1060 	if (iblock != b_off) {
1061 		printk(KERN_DEBUG "%s: block number too large\n", __func__);
1062 		goto abort;
1063 	}
1064 
1065 
1066 	offset = 0;
1067 	firstext = ei->i_first_extent;
1068 	sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1069 	nextblk = ei->i_next_section_block;
1070 	nextoff = ei->i_next_section_offset;
1071 	section = 0;
1072 
1073 	while (nblocks) {
1074 		/* If we are *way* beyond the end of the file, print a message.
1075 		 * Access beyond the end of the file up to the next page boundary
1076 		 * is normal, however because of the way the page cache works.
1077 		 * In this case, we just return 0 so that we can properly fill
1078 		 * the page with useless information without generating any
1079 		 * I/O errors.
1080 		 */
1081 		if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1082 			printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1083 				__func__, b_off,
1084 				(unsigned long long)inode->i_size);
1085 			goto abort;
1086 		}
1087 
1088 		/* On the last section, nextblk == 0, section size is likely to
1089 		 * exceed sect_size by a partial block, and access beyond the
1090 		 * end of the file will reach beyond the section size, too.
1091 		 */
1092 		while (nextblk && (b_off >= (offset + sect_size))) {
1093 			struct inode *ninode;
1094 
1095 			offset += sect_size;
1096 			ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1097 			if (IS_ERR(ninode)) {
1098 				error = PTR_ERR(ninode);
1099 				goto abort;
1100 			}
1101 			firstext  = ISOFS_I(ninode)->i_first_extent;
1102 			sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1103 			nextblk   = ISOFS_I(ninode)->i_next_section_block;
1104 			nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1105 			iput(ninode);
1106 
1107 			if (++section > 100) {
1108 				printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1109 					" aborting...\n", __func__);
1110 				printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1111 					"nextblk=%lu nextoff=%lu\n", __func__,
1112 					b_off, firstext, (unsigned) sect_size,
1113 					nextblk, nextoff);
1114 				goto abort;
1115 			}
1116 		}
1117 
1118 		if (*bh) {
1119 			map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1120 		} else {
1121 			*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1122 			if (!*bh)
1123 				goto abort;
1124 		}
1125 		bh++;	/* Next buffer head */
1126 		b_off++;	/* Next buffer offset */
1127 		nblocks--;
1128 		rv++;
1129 	}
1130 
1131 	error = 0;
1132 abort:
1133 	return rv != 0 ? rv : error;
1134 }
1135 
1136 /*
1137  * Used by the standard interfaces.
1138  */
1139 static int isofs_get_block(struct inode *inode, sector_t iblock,
1140 		    struct buffer_head *bh_result, int create)
1141 {
1142 	int ret;
1143 
1144 	if (create) {
1145 		printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1146 		return -EROFS;
1147 	}
1148 
1149 	ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1150 	return ret < 0 ? ret : 0;
1151 }
1152 
1153 static int isofs_bmap(struct inode *inode, sector_t block)
1154 {
1155 	struct buffer_head dummy;
1156 	int error;
1157 
1158 	dummy.b_state = 0;
1159 	dummy.b_blocknr = -1000;
1160 	error = isofs_get_block(inode, block, &dummy, 0);
1161 	if (!error)
1162 		return dummy.b_blocknr;
1163 	return 0;
1164 }
1165 
1166 struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1167 {
1168 	sector_t blknr = isofs_bmap(inode, block);
1169 	if (!blknr)
1170 		return NULL;
1171 	return sb_bread(inode->i_sb, blknr);
1172 }
1173 
1174 static int isofs_readpage(struct file *file, struct page *page)
1175 {
1176 	return mpage_readpage(page, isofs_get_block);
1177 }
1178 
1179 static int isofs_readpages(struct file *file, struct address_space *mapping,
1180 			struct list_head *pages, unsigned nr_pages)
1181 {
1182 	return mpage_readpages(mapping, pages, nr_pages, isofs_get_block);
1183 }
1184 
1185 static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1186 {
1187 	return generic_block_bmap(mapping,block,isofs_get_block);
1188 }
1189 
1190 static const struct address_space_operations isofs_aops = {
1191 	.readpage = isofs_readpage,
1192 	.readpages = isofs_readpages,
1193 	.bmap = _isofs_bmap
1194 };
1195 
1196 static int isofs_read_level3_size(struct inode *inode)
1197 {
1198 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1199 	int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1200 	struct buffer_head *bh = NULL;
1201 	unsigned long block, offset, block_saved, offset_saved;
1202 	int i = 0;
1203 	int more_entries = 0;
1204 	struct iso_directory_record *tmpde = NULL;
1205 	struct iso_inode_info *ei = ISOFS_I(inode);
1206 
1207 	inode->i_size = 0;
1208 
1209 	/* The first 16 blocks are reserved as the System Area.  Thus,
1210 	 * no inodes can appear in block 0.  We use this to flag that
1211 	 * this is the last section. */
1212 	ei->i_next_section_block = 0;
1213 	ei->i_next_section_offset = 0;
1214 
1215 	block = ei->i_iget5_block;
1216 	offset = ei->i_iget5_offset;
1217 
1218 	do {
1219 		struct iso_directory_record *de;
1220 		unsigned int de_len;
1221 
1222 		if (!bh) {
1223 			bh = sb_bread(inode->i_sb, block);
1224 			if (!bh)
1225 				goto out_noread;
1226 		}
1227 		de = (struct iso_directory_record *) (bh->b_data + offset);
1228 		de_len = *(unsigned char *) de;
1229 
1230 		if (de_len == 0) {
1231 			brelse(bh);
1232 			bh = NULL;
1233 			++block;
1234 			offset = 0;
1235 			continue;
1236 		}
1237 
1238 		block_saved = block;
1239 		offset_saved = offset;
1240 		offset += de_len;
1241 
1242 		/* Make sure we have a full directory entry */
1243 		if (offset >= bufsize) {
1244 			int slop = bufsize - offset + de_len;
1245 			if (!tmpde) {
1246 				tmpde = kmalloc(256, GFP_KERNEL);
1247 				if (!tmpde)
1248 					goto out_nomem;
1249 			}
1250 			memcpy(tmpde, de, slop);
1251 			offset &= bufsize - 1;
1252 			block++;
1253 			brelse(bh);
1254 			bh = NULL;
1255 			if (offset) {
1256 				bh = sb_bread(inode->i_sb, block);
1257 				if (!bh)
1258 					goto out_noread;
1259 				memcpy((void *)tmpde+slop, bh->b_data, offset);
1260 			}
1261 			de = tmpde;
1262 		}
1263 
1264 		inode->i_size += isonum_733(de->size);
1265 		if (i == 1) {
1266 			ei->i_next_section_block = block_saved;
1267 			ei->i_next_section_offset = offset_saved;
1268 		}
1269 
1270 		more_entries = de->flags[-high_sierra] & 0x80;
1271 
1272 		i++;
1273 		if (i > 100)
1274 			goto out_toomany;
1275 	} while (more_entries);
1276 out:
1277 	kfree(tmpde);
1278 	if (bh)
1279 		brelse(bh);
1280 	return 0;
1281 
1282 out_nomem:
1283 	if (bh)
1284 		brelse(bh);
1285 	return -ENOMEM;
1286 
1287 out_noread:
1288 	printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1289 	kfree(tmpde);
1290 	return -EIO;
1291 
1292 out_toomany:
1293 	printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1294 		"isofs_read_level3_size: inode=%lu\n",
1295 		__func__, inode->i_ino);
1296 	goto out;
1297 }
1298 
1299 static int isofs_read_inode(struct inode *inode, int relocated)
1300 {
1301 	struct super_block *sb = inode->i_sb;
1302 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
1303 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1304 	unsigned long block;
1305 	int high_sierra = sbi->s_high_sierra;
1306 	struct buffer_head *bh;
1307 	struct iso_directory_record *de;
1308 	struct iso_directory_record *tmpde = NULL;
1309 	unsigned int de_len;
1310 	unsigned long offset;
1311 	struct iso_inode_info *ei = ISOFS_I(inode);
1312 	int ret = -EIO;
1313 
1314 	block = ei->i_iget5_block;
1315 	bh = sb_bread(inode->i_sb, block);
1316 	if (!bh)
1317 		goto out_badread;
1318 
1319 	offset = ei->i_iget5_offset;
1320 
1321 	de = (struct iso_directory_record *) (bh->b_data + offset);
1322 	de_len = *(unsigned char *) de;
1323 
1324 	if (offset + de_len > bufsize) {
1325 		int frag1 = bufsize - offset;
1326 
1327 		tmpde = kmalloc(de_len, GFP_KERNEL);
1328 		if (!tmpde) {
1329 			ret = -ENOMEM;
1330 			goto fail;
1331 		}
1332 		memcpy(tmpde, bh->b_data + offset, frag1);
1333 		brelse(bh);
1334 		bh = sb_bread(inode->i_sb, ++block);
1335 		if (!bh)
1336 			goto out_badread;
1337 		memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1338 		de = tmpde;
1339 	}
1340 
1341 	inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1342 					ei->i_iget5_offset,
1343 					ISOFS_BUFFER_BITS(inode));
1344 
1345 	/* Assume it is a normal-format file unless told otherwise */
1346 	ei->i_file_format = isofs_file_normal;
1347 
1348 	if (de->flags[-high_sierra] & 2) {
1349 		if (sbi->s_dmode != ISOFS_INVALID_MODE)
1350 			inode->i_mode = S_IFDIR | sbi->s_dmode;
1351 		else
1352 			inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1353 		set_nlink(inode, 1);	/*
1354 					 * Set to 1.  We know there are 2, but
1355 					 * the find utility tries to optimize
1356 					 * if it is 2, and it screws up.  It is
1357 					 * easier to give 1 which tells find to
1358 					 * do it the hard way.
1359 					 */
1360 	} else {
1361 		if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1362 			inode->i_mode = S_IFREG | sbi->s_fmode;
1363 		} else {
1364 			/*
1365 			 * Set default permissions: r-x for all.  The disc
1366 			 * could be shared with DOS machines so virtually
1367 			 * anything could be a valid executable.
1368 			 */
1369 			inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1370 		}
1371 		set_nlink(inode, 1);
1372 	}
1373 	inode->i_uid = sbi->s_uid;
1374 	inode->i_gid = sbi->s_gid;
1375 	inode->i_blocks = 0;
1376 
1377 	ei->i_format_parm[0] = 0;
1378 	ei->i_format_parm[1] = 0;
1379 	ei->i_format_parm[2] = 0;
1380 
1381 	ei->i_section_size = isonum_733(de->size);
1382 	if (de->flags[-high_sierra] & 0x80) {
1383 		ret = isofs_read_level3_size(inode);
1384 		if (ret < 0)
1385 			goto fail;
1386 		ret = -EIO;
1387 	} else {
1388 		ei->i_next_section_block = 0;
1389 		ei->i_next_section_offset = 0;
1390 		inode->i_size = isonum_733(de->size);
1391 	}
1392 
1393 	/*
1394 	 * Some dipshit decided to store some other bit of information
1395 	 * in the high byte of the file length.  Truncate size in case
1396 	 * this CDROM was mounted with the cruft option.
1397 	 */
1398 
1399 	if (sbi->s_cruft)
1400 		inode->i_size &= 0x00ffffff;
1401 
1402 	if (de->interleave[0]) {
1403 		printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1404 		inode->i_size = 0;
1405 	}
1406 
1407 	/* I have no idea what file_unit_size is used for, so
1408 	   we will flag it for now */
1409 	if (de->file_unit_size[0] != 0) {
1410 		printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1411 			inode->i_ino);
1412 	}
1413 
1414 	/* I have no idea what other flag bits are used for, so
1415 	   we will flag it for now */
1416 #ifdef DEBUG
1417 	if((de->flags[-high_sierra] & ~2)!= 0){
1418 		printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1419 				"(%ld %x).\n",
1420 			inode->i_ino, de->flags[-high_sierra]);
1421 	}
1422 #endif
1423 
1424 	inode->i_mtime.tv_sec =
1425 	inode->i_atime.tv_sec =
1426 	inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
1427 	inode->i_mtime.tv_nsec =
1428 	inode->i_atime.tv_nsec =
1429 	inode->i_ctime.tv_nsec = 0;
1430 
1431 	ei->i_first_extent = (isonum_733(de->extent) +
1432 			isonum_711(de->ext_attr_length));
1433 
1434 	/* Set the number of blocks for stat() - should be done before RR */
1435 	inode->i_blocks = (inode->i_size + 511) >> 9;
1436 
1437 	/*
1438 	 * Now test for possible Rock Ridge extensions which will override
1439 	 * some of these numbers in the inode structure.
1440 	 */
1441 
1442 	if (!high_sierra) {
1443 		parse_rock_ridge_inode(de, inode, relocated);
1444 		/* if we want uid/gid set, override the rock ridge setting */
1445 		if (sbi->s_uid_set)
1446 			inode->i_uid = sbi->s_uid;
1447 		if (sbi->s_gid_set)
1448 			inode->i_gid = sbi->s_gid;
1449 	}
1450 	/* Now set final access rights if overriding rock ridge setting */
1451 	if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1452 	    sbi->s_dmode != ISOFS_INVALID_MODE)
1453 		inode->i_mode = S_IFDIR | sbi->s_dmode;
1454 	if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1455 	    sbi->s_fmode != ISOFS_INVALID_MODE)
1456 		inode->i_mode = S_IFREG | sbi->s_fmode;
1457 
1458 	/* Install the inode operations vector */
1459 	if (S_ISREG(inode->i_mode)) {
1460 		inode->i_fop = &generic_ro_fops;
1461 		switch (ei->i_file_format) {
1462 #ifdef CONFIG_ZISOFS
1463 		case isofs_file_compressed:
1464 			inode->i_data.a_ops = &zisofs_aops;
1465 			break;
1466 #endif
1467 		default:
1468 			inode->i_data.a_ops = &isofs_aops;
1469 			break;
1470 		}
1471 	} else if (S_ISDIR(inode->i_mode)) {
1472 		inode->i_op = &isofs_dir_inode_operations;
1473 		inode->i_fop = &isofs_dir_operations;
1474 	} else if (S_ISLNK(inode->i_mode)) {
1475 		inode->i_op = &page_symlink_inode_operations;
1476 		inode_nohighmem(inode);
1477 		inode->i_data.a_ops = &isofs_symlink_aops;
1478 	} else
1479 		/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1480 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1481 
1482 	ret = 0;
1483 out:
1484 	kfree(tmpde);
1485 	if (bh)
1486 		brelse(bh);
1487 	return ret;
1488 
1489 out_badread:
1490 	printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1491 fail:
1492 	goto out;
1493 }
1494 
1495 struct isofs_iget5_callback_data {
1496 	unsigned long block;
1497 	unsigned long offset;
1498 };
1499 
1500 static int isofs_iget5_test(struct inode *ino, void *data)
1501 {
1502 	struct iso_inode_info *i = ISOFS_I(ino);
1503 	struct isofs_iget5_callback_data *d =
1504 		(struct isofs_iget5_callback_data*)data;
1505 	return (i->i_iget5_block == d->block)
1506 		&& (i->i_iget5_offset == d->offset);
1507 }
1508 
1509 static int isofs_iget5_set(struct inode *ino, void *data)
1510 {
1511 	struct iso_inode_info *i = ISOFS_I(ino);
1512 	struct isofs_iget5_callback_data *d =
1513 		(struct isofs_iget5_callback_data*)data;
1514 	i->i_iget5_block = d->block;
1515 	i->i_iget5_offset = d->offset;
1516 	return 0;
1517 }
1518 
1519 /* Store, in the inode's containing structure, the block and block
1520  * offset that point to the underlying meta-data for the inode.  The
1521  * code below is otherwise similar to the iget() code in
1522  * include/linux/fs.h */
1523 struct inode *__isofs_iget(struct super_block *sb,
1524 			   unsigned long block,
1525 			   unsigned long offset,
1526 			   int relocated)
1527 {
1528 	unsigned long hashval;
1529 	struct inode *inode;
1530 	struct isofs_iget5_callback_data data;
1531 	long ret;
1532 
1533 	if (offset >= 1ul << sb->s_blocksize_bits)
1534 		return ERR_PTR(-EINVAL);
1535 
1536 	data.block = block;
1537 	data.offset = offset;
1538 
1539 	hashval = (block << sb->s_blocksize_bits) | offset;
1540 
1541 	inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1542 				&isofs_iget5_set, &data);
1543 
1544 	if (!inode)
1545 		return ERR_PTR(-ENOMEM);
1546 
1547 	if (inode->i_state & I_NEW) {
1548 		ret = isofs_read_inode(inode, relocated);
1549 		if (ret < 0) {
1550 			iget_failed(inode);
1551 			inode = ERR_PTR(ret);
1552 		} else {
1553 			unlock_new_inode(inode);
1554 		}
1555 	}
1556 
1557 	return inode;
1558 }
1559 
1560 static struct dentry *isofs_mount(struct file_system_type *fs_type,
1561 	int flags, const char *dev_name, void *data)
1562 {
1563 	return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1564 }
1565 
1566 static struct file_system_type iso9660_fs_type = {
1567 	.owner		= THIS_MODULE,
1568 	.name		= "iso9660",
1569 	.mount		= isofs_mount,
1570 	.kill_sb	= kill_block_super,
1571 	.fs_flags	= FS_REQUIRES_DEV,
1572 };
1573 MODULE_ALIAS_FS("iso9660");
1574 MODULE_ALIAS("iso9660");
1575 
1576 static int __init init_iso9660_fs(void)
1577 {
1578 	int err = init_inodecache();
1579 	if (err)
1580 		goto out;
1581 #ifdef CONFIG_ZISOFS
1582 	err = zisofs_init();
1583 	if (err)
1584 		goto out1;
1585 #endif
1586 	err = register_filesystem(&iso9660_fs_type);
1587 	if (err)
1588 		goto out2;
1589 	return 0;
1590 out2:
1591 #ifdef CONFIG_ZISOFS
1592 	zisofs_cleanup();
1593 out1:
1594 #endif
1595 	destroy_inodecache();
1596 out:
1597 	return err;
1598 }
1599 
1600 static void __exit exit_iso9660_fs(void)
1601 {
1602         unregister_filesystem(&iso9660_fs_type);
1603 #ifdef CONFIG_ZISOFS
1604 	zisofs_cleanup();
1605 #endif
1606 	destroy_inodecache();
1607 }
1608 
1609 module_init(init_iso9660_fs)
1610 module_exit(exit_iso9660_fs)
1611 MODULE_LICENSE("GPL");
1612