xref: /openbmc/linux/fs/isofs/inode.c (revision 5d331b7f)
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 #include <linux/blkdev.h>
28 
29 #include "isofs.h"
30 #include "zisofs.h"
31 
32 #define BEQUIET
33 
34 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
35 static int isofs_dentry_cmpi(const struct dentry *dentry,
36 		unsigned int len, const char *str, const struct qstr *name);
37 
38 #ifdef CONFIG_JOLIET
39 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
40 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
41 static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
42 		unsigned int len, const char *str, const struct qstr *name);
43 static int isofs_dentry_cmp_ms(const struct dentry *dentry,
44 		unsigned int len, const char *str, const struct qstr *name);
45 #endif
46 
47 static void isofs_put_super(struct super_block *sb)
48 {
49 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
50 
51 #ifdef CONFIG_JOLIET
52 	unload_nls(sbi->s_nls_iocharset);
53 #endif
54 
55 	kfree(sbi);
56 	sb->s_fs_info = NULL;
57 	return;
58 }
59 
60 static int isofs_read_inode(struct inode *, int relocated);
61 static int isofs_statfs (struct dentry *, struct kstatfs *);
62 static int isofs_show_options(struct seq_file *, struct dentry *);
63 
64 static struct kmem_cache *isofs_inode_cachep;
65 
66 static struct inode *isofs_alloc_inode(struct super_block *sb)
67 {
68 	struct iso_inode_info *ei;
69 	ei = kmem_cache_alloc(isofs_inode_cachep, GFP_KERNEL);
70 	if (!ei)
71 		return NULL;
72 	return &ei->vfs_inode;
73 }
74 
75 static void isofs_i_callback(struct rcu_head *head)
76 {
77 	struct inode *inode = container_of(head, struct inode, i_rcu);
78 	kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
79 }
80 
81 static void isofs_destroy_inode(struct inode *inode)
82 {
83 	call_rcu(&inode->i_rcu, isofs_i_callback);
84 }
85 
86 static void init_once(void *foo)
87 {
88 	struct iso_inode_info *ei = foo;
89 
90 	inode_init_once(&ei->vfs_inode);
91 }
92 
93 static int __init init_inodecache(void)
94 {
95 	isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
96 					sizeof(struct iso_inode_info),
97 					0, (SLAB_RECLAIM_ACCOUNT|
98 					SLAB_MEM_SPREAD|SLAB_ACCOUNT),
99 					init_once);
100 	if (!isofs_inode_cachep)
101 		return -ENOMEM;
102 	return 0;
103 }
104 
105 static void destroy_inodecache(void)
106 {
107 	/*
108 	 * Make sure all delayed rcu free inodes are flushed before we
109 	 * destroy cache.
110 	 */
111 	rcu_barrier();
112 	kmem_cache_destroy(isofs_inode_cachep);
113 }
114 
115 static int isofs_remount(struct super_block *sb, int *flags, char *data)
116 {
117 	sync_filesystem(sb);
118 	if (!(*flags & SB_RDONLY))
119 		return -EROFS;
120 	return 0;
121 }
122 
123 static const struct super_operations isofs_sops = {
124 	.alloc_inode	= isofs_alloc_inode,
125 	.destroy_inode	= isofs_destroy_inode,
126 	.put_super	= isofs_put_super,
127 	.statfs		= isofs_statfs,
128 	.remount_fs	= isofs_remount,
129 	.show_options	= isofs_show_options,
130 };
131 
132 
133 static const struct dentry_operations isofs_dentry_ops[] = {
134 	{
135 		.d_hash		= isofs_hashi,
136 		.d_compare	= isofs_dentry_cmpi,
137 	},
138 #ifdef CONFIG_JOLIET
139 	{
140 		.d_hash		= isofs_hash_ms,
141 		.d_compare	= isofs_dentry_cmp_ms,
142 	},
143 	{
144 		.d_hash		= isofs_hashi_ms,
145 		.d_compare	= isofs_dentry_cmpi_ms,
146 	},
147 #endif
148 };
149 
150 struct iso9660_options{
151 	unsigned int rock:1;
152 	unsigned int joliet:1;
153 	unsigned int cruft:1;
154 	unsigned int hide:1;
155 	unsigned int showassoc:1;
156 	unsigned int nocompress:1;
157 	unsigned int overriderockperm:1;
158 	unsigned int uid_set:1;
159 	unsigned int gid_set:1;
160 	unsigned int utf8:1;
161 	unsigned char map;
162 	unsigned char check;
163 	unsigned int blocksize;
164 	umode_t fmode;
165 	umode_t dmode;
166 	kgid_t gid;
167 	kuid_t uid;
168 	char *iocharset;
169 	/* LVE */
170 	s32 session;
171 	s32 sbsector;
172 };
173 
174 /*
175  * Compute the hash for the isofs name corresponding to the dentry.
176  */
177 static int
178 isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
179 {
180 	const char *name;
181 	int len;
182 	char c;
183 	unsigned long hash;
184 
185 	len = qstr->len;
186 	name = qstr->name;
187 	if (ms) {
188 		while (len && name[len-1] == '.')
189 			len--;
190 	}
191 
192 	hash = init_name_hash(dentry);
193 	while (len--) {
194 		c = tolower(*name++);
195 		hash = partial_name_hash(c, hash);
196 	}
197 	qstr->hash = end_name_hash(hash);
198 
199 	return 0;
200 }
201 
202 /*
203  * Compare of two isofs names.
204  */
205 static int isofs_dentry_cmp_common(
206 		unsigned int len, const char *str,
207 		const struct qstr *name, int ms, int ci)
208 {
209 	int alen, blen;
210 
211 	/* A filename cannot end in '.' or we treat it like it has none */
212 	alen = name->len;
213 	blen = len;
214 	if (ms) {
215 		while (alen && name->name[alen-1] == '.')
216 			alen--;
217 		while (blen && str[blen-1] == '.')
218 			blen--;
219 	}
220 	if (alen == blen) {
221 		if (ci) {
222 			if (strncasecmp(name->name, str, alen) == 0)
223 				return 0;
224 		} else {
225 			if (strncmp(name->name, str, alen) == 0)
226 				return 0;
227 		}
228 	}
229 	return 1;
230 }
231 
232 static int
233 isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
234 {
235 	return isofs_hashi_common(dentry, qstr, 0);
236 }
237 
238 static int
239 isofs_dentry_cmpi(const struct dentry *dentry,
240 		unsigned int len, const char *str, const struct qstr *name)
241 {
242 	return isofs_dentry_cmp_common(len, str, name, 0, 1);
243 }
244 
245 #ifdef CONFIG_JOLIET
246 /*
247  * Compute the hash for the isofs name corresponding to the dentry.
248  */
249 static int
250 isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
251 {
252 	const char *name;
253 	int len;
254 
255 	len = qstr->len;
256 	name = qstr->name;
257 	if (ms) {
258 		while (len && name[len-1] == '.')
259 			len--;
260 	}
261 
262 	qstr->hash = full_name_hash(dentry, name, len);
263 
264 	return 0;
265 }
266 
267 static int
268 isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
269 {
270 	return isofs_hash_common(dentry, qstr, 1);
271 }
272 
273 static int
274 isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
275 {
276 	return isofs_hashi_common(dentry, qstr, 1);
277 }
278 
279 static int
280 isofs_dentry_cmp_ms(const struct dentry *dentry,
281 		unsigned int len, const char *str, const struct qstr *name)
282 {
283 	return isofs_dentry_cmp_common(len, str, name, 1, 0);
284 }
285 
286 static int
287 isofs_dentry_cmpi_ms(const struct dentry *dentry,
288 		unsigned int len, const char *str, const struct qstr *name)
289 {
290 	return isofs_dentry_cmp_common(len, str, name, 1, 1);
291 }
292 #endif
293 
294 enum {
295 	Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
296 	Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
297 	Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
298 	Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
299 };
300 
301 static const match_table_t tokens = {
302 	{Opt_norock, "norock"},
303 	{Opt_nojoliet, "nojoliet"},
304 	{Opt_unhide, "unhide"},
305 	{Opt_hide, "hide"},
306 	{Opt_showassoc, "showassoc"},
307 	{Opt_cruft, "cruft"},
308 	{Opt_utf8, "utf8"},
309 	{Opt_iocharset, "iocharset=%s"},
310 	{Opt_map_a, "map=acorn"},
311 	{Opt_map_a, "map=a"},
312 	{Opt_map_n, "map=normal"},
313 	{Opt_map_n, "map=n"},
314 	{Opt_map_o, "map=off"},
315 	{Opt_map_o, "map=o"},
316 	{Opt_session, "session=%u"},
317 	{Opt_sb, "sbsector=%u"},
318 	{Opt_check_r, "check=relaxed"},
319 	{Opt_check_r, "check=r"},
320 	{Opt_check_s, "check=strict"},
321 	{Opt_check_s, "check=s"},
322 	{Opt_uid, "uid=%u"},
323 	{Opt_gid, "gid=%u"},
324 	{Opt_mode, "mode=%u"},
325 	{Opt_dmode, "dmode=%u"},
326 	{Opt_overriderockperm, "overriderockperm"},
327 	{Opt_block, "block=%u"},
328 	{Opt_ignore, "conv=binary"},
329 	{Opt_ignore, "conv=b"},
330 	{Opt_ignore, "conv=text"},
331 	{Opt_ignore, "conv=t"},
332 	{Opt_ignore, "conv=mtext"},
333 	{Opt_ignore, "conv=m"},
334 	{Opt_ignore, "conv=auto"},
335 	{Opt_ignore, "conv=a"},
336 	{Opt_nocompress, "nocompress"},
337 	{Opt_err, NULL}
338 };
339 
340 static int parse_options(char *options, struct iso9660_options *popt)
341 {
342 	char *p;
343 	int option;
344 
345 	popt->map = 'n';
346 	popt->rock = 1;
347 	popt->joliet = 1;
348 	popt->cruft = 0;
349 	popt->hide = 0;
350 	popt->showassoc = 0;
351 	popt->check = 'u';		/* unset */
352 	popt->nocompress = 0;
353 	popt->blocksize = 1024;
354 	popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
355 	popt->uid_set = 0;
356 	popt->gid_set = 0;
357 	popt->gid = GLOBAL_ROOT_GID;
358 	popt->uid = GLOBAL_ROOT_UID;
359 	popt->iocharset = NULL;
360 	popt->utf8 = 0;
361 	popt->overriderockperm = 0;
362 	popt->session=-1;
363 	popt->sbsector=-1;
364 	if (!options)
365 		return 1;
366 
367 	while ((p = strsep(&options, ",")) != NULL) {
368 		int token;
369 		substring_t args[MAX_OPT_ARGS];
370 		unsigned n;
371 
372 		if (!*p)
373 			continue;
374 
375 		token = match_token(p, tokens, args);
376 		switch (token) {
377 		case Opt_norock:
378 			popt->rock = 0;
379 			break;
380 		case Opt_nojoliet:
381 			popt->joliet = 0;
382 			break;
383 		case Opt_hide:
384 			popt->hide = 1;
385 			break;
386 		case Opt_unhide:
387 		case Opt_showassoc:
388 			popt->showassoc = 1;
389 			break;
390 		case Opt_cruft:
391 			popt->cruft = 1;
392 			break;
393 		case Opt_utf8:
394 			popt->utf8 = 1;
395 			break;
396 #ifdef CONFIG_JOLIET
397 		case Opt_iocharset:
398 			kfree(popt->iocharset);
399 			popt->iocharset = match_strdup(&args[0]);
400 			if (!popt->iocharset)
401 				return 0;
402 			break;
403 #endif
404 		case Opt_map_a:
405 			popt->map = 'a';
406 			break;
407 		case Opt_map_o:
408 			popt->map = 'o';
409 			break;
410 		case Opt_map_n:
411 			popt->map = 'n';
412 			break;
413 		case Opt_session:
414 			if (match_int(&args[0], &option))
415 				return 0;
416 			n = option;
417 			/*
418 			 * Track numbers are supposed to be in range 1-99, the
419 			 * mount option starts indexing at 0.
420 			 */
421 			if (n >= 99)
422 				return 0;
423 			popt->session = n + 1;
424 			break;
425 		case Opt_sb:
426 			if (match_int(&args[0], &option))
427 				return 0;
428 			popt->sbsector = option;
429 			break;
430 		case Opt_check_r:
431 			popt->check = 'r';
432 			break;
433 		case Opt_check_s:
434 			popt->check = 's';
435 			break;
436 		case Opt_ignore:
437 			break;
438 		case Opt_uid:
439 			if (match_int(&args[0], &option))
440 				return 0;
441 			popt->uid = make_kuid(current_user_ns(), option);
442 			if (!uid_valid(popt->uid))
443 				return 0;
444 			popt->uid_set = 1;
445 			break;
446 		case Opt_gid:
447 			if (match_int(&args[0], &option))
448 				return 0;
449 			popt->gid = make_kgid(current_user_ns(), option);
450 			if (!gid_valid(popt->gid))
451 				return 0;
452 			popt->gid_set = 1;
453 			break;
454 		case Opt_mode:
455 			if (match_int(&args[0], &option))
456 				return 0;
457 			popt->fmode = option;
458 			break;
459 		case Opt_dmode:
460 			if (match_int(&args[0], &option))
461 				return 0;
462 			popt->dmode = option;
463 			break;
464 		case Opt_overriderockperm:
465 			popt->overriderockperm = 1;
466 			break;
467 		case Opt_block:
468 			if (match_int(&args[0], &option))
469 				return 0;
470 			n = option;
471 			if (n != 512 && n != 1024 && n != 2048)
472 				return 0;
473 			popt->blocksize = n;
474 			break;
475 		case Opt_nocompress:
476 			popt->nocompress = 1;
477 			break;
478 		default:
479 			return 0;
480 		}
481 	}
482 	return 1;
483 }
484 
485 /*
486  * Display the mount options in /proc/mounts.
487  */
488 static int isofs_show_options(struct seq_file *m, struct dentry *root)
489 {
490 	struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
491 
492 	if (!sbi->s_rock)		seq_puts(m, ",norock");
493 	else if (!sbi->s_joliet_level)	seq_puts(m, ",nojoliet");
494 	if (sbi->s_cruft)		seq_puts(m, ",cruft");
495 	if (sbi->s_hide)		seq_puts(m, ",hide");
496 	if (sbi->s_nocompress)		seq_puts(m, ",nocompress");
497 	if (sbi->s_overriderockperm)	seq_puts(m, ",overriderockperm");
498 	if (sbi->s_showassoc)		seq_puts(m, ",showassoc");
499 	if (sbi->s_utf8)		seq_puts(m, ",utf8");
500 
501 	if (sbi->s_check)		seq_printf(m, ",check=%c", sbi->s_check);
502 	if (sbi->s_mapping)		seq_printf(m, ",map=%c", sbi->s_mapping);
503 	if (sbi->s_session != 255)	seq_printf(m, ",session=%u", sbi->s_session - 1);
504 	if (sbi->s_sbsector != -1)	seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
505 
506 	if (root->d_sb->s_blocksize != 1024)
507 		seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
508 
509 	if (sbi->s_uid_set)
510 		seq_printf(m, ",uid=%u",
511 			   from_kuid_munged(&init_user_ns, sbi->s_uid));
512 	if (sbi->s_gid_set)
513 		seq_printf(m, ",gid=%u",
514 			   from_kgid_munged(&init_user_ns, sbi->s_gid));
515 
516 	if (sbi->s_dmode != ISOFS_INVALID_MODE)
517 		seq_printf(m, ",dmode=%o", sbi->s_dmode);
518 	if (sbi->s_fmode != ISOFS_INVALID_MODE)
519 		seq_printf(m, ",fmode=%o", sbi->s_fmode);
520 
521 #ifdef CONFIG_JOLIET
522 	if (sbi->s_nls_iocharset &&
523 	    strcmp(sbi->s_nls_iocharset->charset, CONFIG_NLS_DEFAULT) != 0)
524 		seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
525 #endif
526 	return 0;
527 }
528 
529 /*
530  * look if the driver can tell the multi session redirection value
531  *
532  * don't change this if you don't know what you do, please!
533  * Multisession is legal only with XA disks.
534  * A non-XA disk with more than one volume descriptor may do it right, but
535  * usually is written in a nowhere standardized "multi-partition" manner.
536  * Multisession uses absolute addressing (solely the first frame of the whole
537  * track is #0), multi-partition uses relative addressing (each first frame of
538  * each track is #0), and a track is not a session.
539  *
540  * A broken CDwriter software or drive firmware does not set new standards,
541  * at least not if conflicting with the existing ones.
542  *
543  * emoenke@gwdg.de
544  */
545 #define WE_OBEY_THE_WRITTEN_STANDARDS 1
546 
547 static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
548 {
549 	struct cdrom_multisession ms_info;
550 	unsigned int vol_desc_start;
551 	struct block_device *bdev = sb->s_bdev;
552 	int i;
553 
554 	vol_desc_start=0;
555 	ms_info.addr_format=CDROM_LBA;
556 	if (session > 0) {
557 		struct cdrom_tocentry Te;
558 		Te.cdte_track=session;
559 		Te.cdte_format=CDROM_LBA;
560 		i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
561 		if (!i) {
562 			printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
563 				session, Te.cdte_addr.lba,
564 				Te.cdte_ctrl&CDROM_DATA_TRACK);
565 			if ((Te.cdte_ctrl&CDROM_DATA_TRACK) == 4)
566 				return Te.cdte_addr.lba;
567 		}
568 
569 		printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
570 	}
571 	i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long) &ms_info);
572 	if (session > 0)
573 		printk(KERN_ERR "ISOFS: Invalid session number\n");
574 #if 0
575 	printk(KERN_DEBUG "isofs.inode: CDROMMULTISESSION: rc=%d\n",i);
576 	if (i==0) {
577 		printk(KERN_DEBUG "isofs.inode: XA disk: %s\n",ms_info.xa_flag?"yes":"no");
578 		printk(KERN_DEBUG "isofs.inode: vol_desc_start = %d\n", ms_info.addr.lba);
579 	}
580 #endif
581 	if (i==0)
582 #if WE_OBEY_THE_WRITTEN_STANDARDS
583 		if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
584 #endif
585 			vol_desc_start=ms_info.addr.lba;
586 	return vol_desc_start;
587 }
588 
589 /*
590  * Check if root directory is empty (has less than 3 files).
591  *
592  * Used to detect broken CDs where ISO root directory is empty but Joliet root
593  * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
594  * (and Joliet used instead) or else no files would be visible.
595  */
596 static bool rootdir_empty(struct super_block *sb, unsigned long block)
597 {
598 	int offset = 0, files = 0, de_len;
599 	struct iso_directory_record *de;
600 	struct buffer_head *bh;
601 
602 	bh = sb_bread(sb, block);
603 	if (!bh)
604 		return true;
605 	while (files < 3) {
606 		de = (struct iso_directory_record *) (bh->b_data + offset);
607 		de_len = *(unsigned char *) de;
608 		if (de_len == 0)
609 			break;
610 		files++;
611 		offset += de_len;
612 	}
613 	brelse(bh);
614 	return files < 3;
615 }
616 
617 /*
618  * Initialize the superblock and read the root inode.
619  *
620  * Note: a check_disk_change() has been done immediately prior
621  * to this call, so we don't need to check again.
622  */
623 static int isofs_fill_super(struct super_block *s, void *data, int silent)
624 {
625 	struct buffer_head *bh = NULL, *pri_bh = NULL;
626 	struct hs_primary_descriptor *h_pri = NULL;
627 	struct iso_primary_descriptor *pri = NULL;
628 	struct iso_supplementary_descriptor *sec = NULL;
629 	struct iso_directory_record *rootp;
630 	struct inode *inode;
631 	struct iso9660_options opt;
632 	struct isofs_sb_info *sbi;
633 	unsigned long first_data_zone;
634 	int joliet_level = 0;
635 	int iso_blknum, block;
636 	int orig_zonesize;
637 	int table, error = -EINVAL;
638 	unsigned int vol_desc_start;
639 
640 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
641 	if (!sbi)
642 		return -ENOMEM;
643 	s->s_fs_info = sbi;
644 
645 	if (!parse_options((char *)data, &opt))
646 		goto out_freesbi;
647 
648 	/*
649 	 * First of all, get the hardware blocksize for this device.
650 	 * If we don't know what it is, or the hardware blocksize is
651 	 * larger than the blocksize the user specified, then use
652 	 * that value.
653 	 */
654 	/*
655 	 * What if bugger tells us to go beyond page size?
656 	 */
657 	if (bdev_logical_block_size(s->s_bdev) > 2048) {
658 		printk(KERN_WARNING
659 		       "ISOFS: unsupported/invalid hardware sector size %d\n",
660 			bdev_logical_block_size(s->s_bdev));
661 		goto out_freesbi;
662 	}
663 	opt.blocksize = sb_min_blocksize(s, opt.blocksize);
664 
665 	sbi->s_high_sierra = 0; /* default is iso9660 */
666 	sbi->s_session = opt.session;
667 	sbi->s_sbsector = opt.sbsector;
668 
669 	vol_desc_start = (opt.sbsector != -1) ?
670 		opt.sbsector : isofs_get_last_session(s,opt.session);
671 
672 	for (iso_blknum = vol_desc_start+16;
673 		iso_blknum < vol_desc_start+100; iso_blknum++) {
674 		struct hs_volume_descriptor *hdp;
675 		struct iso_volume_descriptor  *vdp;
676 
677 		block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
678 		if (!(bh = sb_bread(s, block)))
679 			goto out_no_read;
680 
681 		vdp = (struct iso_volume_descriptor *)bh->b_data;
682 		hdp = (struct hs_volume_descriptor *)bh->b_data;
683 
684 		/*
685 		 * Due to the overlapping physical location of the descriptors,
686 		 * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
687 		 * proper identification in this case, we first check for ISO.
688 		 */
689 		if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
690 			if (isonum_711(vdp->type) == ISO_VD_END)
691 				break;
692 			if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
693 				if (!pri) {
694 					pri = (struct iso_primary_descriptor *)vdp;
695 					/* Save the buffer in case we need it ... */
696 					pri_bh = bh;
697 					bh = NULL;
698 				}
699 			}
700 #ifdef CONFIG_JOLIET
701 			else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
702 				sec = (struct iso_supplementary_descriptor *)vdp;
703 				if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
704 					if (opt.joliet) {
705 						if (sec->escape[2] == 0x40)
706 							joliet_level = 1;
707 						else if (sec->escape[2] == 0x43)
708 							joliet_level = 2;
709 						else if (sec->escape[2] == 0x45)
710 							joliet_level = 3;
711 
712 						printk(KERN_DEBUG "ISO 9660 Extensions: "
713 							"Microsoft Joliet Level %d\n",
714 							joliet_level);
715 					}
716 					goto root_found;
717 				} else {
718 				/* Unknown supplementary volume descriptor */
719 				sec = NULL;
720 				}
721 			}
722 #endif
723 		} else {
724 			if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
725 				if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
726 					goto out_freebh;
727 
728 				sbi->s_high_sierra = 1;
729 				opt.rock = 0;
730 				h_pri = (struct hs_primary_descriptor *)vdp;
731 				goto root_found;
732 			}
733 		}
734 
735 		/* Just skip any volume descriptors we don't recognize */
736 
737 		brelse(bh);
738 		bh = NULL;
739 	}
740 	/*
741 	 * If we fall through, either no volume descriptor was found,
742 	 * or else we passed a primary descriptor looking for others.
743 	 */
744 	if (!pri)
745 		goto out_unknown_format;
746 	brelse(bh);
747 	bh = pri_bh;
748 	pri_bh = NULL;
749 
750 root_found:
751 	/* We don't support read-write mounts */
752 	if (!sb_rdonly(s)) {
753 		error = -EACCES;
754 		goto out_freebh;
755 	}
756 
757 	if (joliet_level && (!pri || !opt.rock)) {
758 		/* This is the case of Joliet with the norock mount flag.
759 		 * A disc with both Joliet and Rock Ridge is handled later
760 		 */
761 		pri = (struct iso_primary_descriptor *) sec;
762 	}
763 
764 	if(sbi->s_high_sierra){
765 		rootp = (struct iso_directory_record *) h_pri->root_directory_record;
766 		sbi->s_nzones = isonum_733(h_pri->volume_space_size);
767 		sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
768 		sbi->s_max_size = isonum_733(h_pri->volume_space_size);
769 	} else {
770 		if (!pri)
771 			goto out_freebh;
772 		rootp = (struct iso_directory_record *) pri->root_directory_record;
773 		sbi->s_nzones = isonum_733(pri->volume_space_size);
774 		sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
775 		sbi->s_max_size = isonum_733(pri->volume_space_size);
776 	}
777 
778 	sbi->s_ninodes = 0; /* No way to figure this out easily */
779 
780 	orig_zonesize = sbi->s_log_zone_size;
781 	/*
782 	 * If the zone size is smaller than the hardware sector size,
783 	 * this is a fatal error.  This would occur if the disc drive
784 	 * had sectors that were 2048 bytes, but the filesystem had
785 	 * blocks that were 512 bytes (which should only very rarely
786 	 * happen.)
787 	 */
788 	if (orig_zonesize < opt.blocksize)
789 		goto out_bad_size;
790 
791 	/* RDE: convert log zone size to bit shift */
792 	switch (sbi->s_log_zone_size) {
793 	case  512: sbi->s_log_zone_size =  9; break;
794 	case 1024: sbi->s_log_zone_size = 10; break;
795 	case 2048: sbi->s_log_zone_size = 11; break;
796 
797 	default:
798 		goto out_bad_zone_size;
799 	}
800 
801 	s->s_magic = ISOFS_SUPER_MAGIC;
802 
803 	/*
804 	 * With multi-extent files, file size is only limited by the maximum
805 	 * size of a file system, which is 8 TB.
806 	 */
807 	s->s_maxbytes = 0x80000000000LL;
808 
809 	/* Set this for reference. Its not currently used except on write
810 	   which we don't have .. */
811 
812 	first_data_zone = isonum_733(rootp->extent) +
813 			  isonum_711(rootp->ext_attr_length);
814 	sbi->s_firstdatazone = first_data_zone;
815 #ifndef BEQUIET
816 	printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
817 		sbi->s_max_size, 1UL << sbi->s_log_zone_size);
818 	printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
819 	if(sbi->s_high_sierra)
820 		printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
821 #endif
822 
823 	/*
824 	 * If the Joliet level is set, we _may_ decide to use the
825 	 * secondary descriptor, but can't be sure until after we
826 	 * read the root inode. But before reading the root inode
827 	 * we may need to change the device blocksize, and would
828 	 * rather release the old buffer first. So, we cache the
829 	 * first_data_zone value from the secondary descriptor.
830 	 */
831 	if (joliet_level) {
832 		pri = (struct iso_primary_descriptor *) sec;
833 		rootp = (struct iso_directory_record *)
834 			pri->root_directory_record;
835 		first_data_zone = isonum_733(rootp->extent) +
836 				isonum_711(rootp->ext_attr_length);
837 	}
838 
839 	/*
840 	 * We're all done using the volume descriptor, and may need
841 	 * to change the device blocksize, so release the buffer now.
842 	 */
843 	brelse(pri_bh);
844 	brelse(bh);
845 
846 	/*
847 	 * Force the blocksize to 512 for 512 byte sectors.  The file
848 	 * read primitives really get it wrong in a bad way if we don't
849 	 * do this.
850 	 *
851 	 * Note - we should never be setting the blocksize to something
852 	 * less than the hardware sector size for the device.  If we
853 	 * do, we would end up having to read larger buffers and split
854 	 * out portions to satisfy requests.
855 	 *
856 	 * Note2- the idea here is that we want to deal with the optimal
857 	 * zonesize in the filesystem.  If we have it set to something less,
858 	 * then we have horrible problems with trying to piece together
859 	 * bits of adjacent blocks in order to properly read directory
860 	 * entries.  By forcing the blocksize in this way, we ensure
861 	 * that we will never be required to do this.
862 	 */
863 	sb_set_blocksize(s, orig_zonesize);
864 
865 	sbi->s_nls_iocharset = NULL;
866 
867 #ifdef CONFIG_JOLIET
868 	if (joliet_level && opt.utf8 == 0) {
869 		char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
870 		sbi->s_nls_iocharset = load_nls(p);
871 		if (! sbi->s_nls_iocharset) {
872 			/* Fail only if explicit charset specified */
873 			if (opt.iocharset)
874 				goto out_freesbi;
875 			sbi->s_nls_iocharset = load_nls_default();
876 		}
877 	}
878 #endif
879 	s->s_op = &isofs_sops;
880 	s->s_export_op = &isofs_export_ops;
881 	sbi->s_mapping = opt.map;
882 	sbi->s_rock = (opt.rock ? 2 : 0);
883 	sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
884 	sbi->s_cruft = opt.cruft;
885 	sbi->s_hide = opt.hide;
886 	sbi->s_showassoc = opt.showassoc;
887 	sbi->s_uid = opt.uid;
888 	sbi->s_gid = opt.gid;
889 	sbi->s_uid_set = opt.uid_set;
890 	sbi->s_gid_set = opt.gid_set;
891 	sbi->s_utf8 = opt.utf8;
892 	sbi->s_nocompress = opt.nocompress;
893 	sbi->s_overriderockperm = opt.overriderockperm;
894 	/*
895 	 * It would be incredibly stupid to allow people to mark every file
896 	 * on the disk as suid, so we merely allow them to set the default
897 	 * permissions.
898 	 */
899 	if (opt.fmode != ISOFS_INVALID_MODE)
900 		sbi->s_fmode = opt.fmode & 0777;
901 	else
902 		sbi->s_fmode = ISOFS_INVALID_MODE;
903 	if (opt.dmode != ISOFS_INVALID_MODE)
904 		sbi->s_dmode = opt.dmode & 0777;
905 	else
906 		sbi->s_dmode = ISOFS_INVALID_MODE;
907 
908 	/*
909 	 * Read the root inode, which _may_ result in changing
910 	 * the s_rock flag. Once we have the final s_rock value,
911 	 * we then decide whether to use the Joliet descriptor.
912 	 */
913 	inode = isofs_iget(s, sbi->s_firstdatazone, 0);
914 	if (IS_ERR(inode))
915 		goto out_no_root;
916 
917 	/*
918 	 * Fix for broken CDs with Rock Ridge and empty ISO root directory but
919 	 * correct Joliet root directory.
920 	 */
921 	if (sbi->s_rock == 1 && joliet_level &&
922 				rootdir_empty(s, sbi->s_firstdatazone)) {
923 		printk(KERN_NOTICE
924 			"ISOFS: primary root directory is empty. "
925 			"Disabling Rock Ridge and switching to Joliet.");
926 		sbi->s_rock = 0;
927 	}
928 
929 	/*
930 	 * If this disk has both Rock Ridge and Joliet on it, then we
931 	 * want to use Rock Ridge by default.  This can be overridden
932 	 * by using the norock mount option.  There is still one other
933 	 * possibility that is not taken into account: a Rock Ridge
934 	 * CD with Unicode names.  Until someone sees such a beast, it
935 	 * will not be supported.
936 	 */
937 	if (sbi->s_rock == 1) {
938 		joliet_level = 0;
939 	} else if (joliet_level) {
940 		sbi->s_rock = 0;
941 		if (sbi->s_firstdatazone != first_data_zone) {
942 			sbi->s_firstdatazone = first_data_zone;
943 			printk(KERN_DEBUG
944 				"ISOFS: changing to secondary root\n");
945 			iput(inode);
946 			inode = isofs_iget(s, sbi->s_firstdatazone, 0);
947 			if (IS_ERR(inode))
948 				goto out_no_root;
949 		}
950 	}
951 
952 	if (opt.check == 'u') {
953 		/* Only Joliet is case insensitive by default */
954 		if (joliet_level)
955 			opt.check = 'r';
956 		else
957 			opt.check = 's';
958 	}
959 	sbi->s_joliet_level = joliet_level;
960 
961 	/* Make sure the root inode is a directory */
962 	if (!S_ISDIR(inode->i_mode)) {
963 		printk(KERN_WARNING
964 			"isofs_fill_super: root inode is not a directory. "
965 			"Corrupted media?\n");
966 		goto out_iput;
967 	}
968 
969 	table = 0;
970 	if (joliet_level)
971 		table += 2;
972 	if (opt.check == 'r')
973 		table++;
974 	sbi->s_check = opt.check;
975 
976 	if (table)
977 		s->s_d_op = &isofs_dentry_ops[table - 1];
978 
979 	/* get the root dentry */
980 	s->s_root = d_make_root(inode);
981 	if (!(s->s_root)) {
982 		error = -ENOMEM;
983 		goto out_no_inode;
984 	}
985 
986 	kfree(opt.iocharset);
987 
988 	return 0;
989 
990 	/*
991 	 * Display error messages and free resources.
992 	 */
993 out_iput:
994 	iput(inode);
995 	goto out_no_inode;
996 out_no_root:
997 	error = PTR_ERR(inode);
998 	if (error != -ENOMEM)
999 		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
1000 out_no_inode:
1001 #ifdef CONFIG_JOLIET
1002 	unload_nls(sbi->s_nls_iocharset);
1003 #endif
1004 	goto out_freesbi;
1005 out_no_read:
1006 	printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
1007 		__func__, s->s_id, iso_blknum, block);
1008 	goto out_freebh;
1009 out_bad_zone_size:
1010 	printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
1011 		sbi->s_log_zone_size);
1012 	goto out_freebh;
1013 out_bad_size:
1014 	printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
1015 		orig_zonesize, opt.blocksize);
1016 	goto out_freebh;
1017 out_unknown_format:
1018 	if (!silent)
1019 		printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
1020 
1021 out_freebh:
1022 	brelse(bh);
1023 	brelse(pri_bh);
1024 out_freesbi:
1025 	kfree(opt.iocharset);
1026 	kfree(sbi);
1027 	s->s_fs_info = NULL;
1028 	return error;
1029 }
1030 
1031 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
1032 {
1033 	struct super_block *sb = dentry->d_sb;
1034 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1035 
1036 	buf->f_type = ISOFS_SUPER_MAGIC;
1037 	buf->f_bsize = sb->s_blocksize;
1038 	buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1039 		<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1040 	buf->f_bfree = 0;
1041 	buf->f_bavail = 0;
1042 	buf->f_files = ISOFS_SB(sb)->s_ninodes;
1043 	buf->f_ffree = 0;
1044 	buf->f_fsid.val[0] = (u32)id;
1045 	buf->f_fsid.val[1] = (u32)(id >> 32);
1046 	buf->f_namelen = NAME_MAX;
1047 	return 0;
1048 }
1049 
1050 /*
1051  * Get a set of blocks; filling in buffer_heads if already allocated
1052  * or getblk() if they are not.  Returns the number of blocks inserted
1053  * (-ve == error.)
1054  */
1055 int isofs_get_blocks(struct inode *inode, sector_t iblock,
1056 		     struct buffer_head **bh, unsigned long nblocks)
1057 {
1058 	unsigned long b_off = iblock;
1059 	unsigned offset, sect_size;
1060 	unsigned int firstext;
1061 	unsigned long nextblk, nextoff;
1062 	int section, rv, error;
1063 	struct iso_inode_info *ei = ISOFS_I(inode);
1064 
1065 	error = -EIO;
1066 	rv = 0;
1067 	if (iblock != b_off) {
1068 		printk(KERN_DEBUG "%s: block number too large\n", __func__);
1069 		goto abort;
1070 	}
1071 
1072 
1073 	offset = 0;
1074 	firstext = ei->i_first_extent;
1075 	sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1076 	nextblk = ei->i_next_section_block;
1077 	nextoff = ei->i_next_section_offset;
1078 	section = 0;
1079 
1080 	while (nblocks) {
1081 		/* If we are *way* beyond the end of the file, print a message.
1082 		 * Access beyond the end of the file up to the next page boundary
1083 		 * is normal, however because of the way the page cache works.
1084 		 * In this case, we just return 0 so that we can properly fill
1085 		 * the page with useless information without generating any
1086 		 * I/O errors.
1087 		 */
1088 		if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1089 			printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1090 				__func__, b_off,
1091 				(unsigned long long)inode->i_size);
1092 			goto abort;
1093 		}
1094 
1095 		/* On the last section, nextblk == 0, section size is likely to
1096 		 * exceed sect_size by a partial block, and access beyond the
1097 		 * end of the file will reach beyond the section size, too.
1098 		 */
1099 		while (nextblk && (b_off >= (offset + sect_size))) {
1100 			struct inode *ninode;
1101 
1102 			offset += sect_size;
1103 			ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1104 			if (IS_ERR(ninode)) {
1105 				error = PTR_ERR(ninode);
1106 				goto abort;
1107 			}
1108 			firstext  = ISOFS_I(ninode)->i_first_extent;
1109 			sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1110 			nextblk   = ISOFS_I(ninode)->i_next_section_block;
1111 			nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1112 			iput(ninode);
1113 
1114 			if (++section > 100) {
1115 				printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1116 					" aborting...\n", __func__);
1117 				printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1118 					"nextblk=%lu nextoff=%lu\n", __func__,
1119 					b_off, firstext, (unsigned) sect_size,
1120 					nextblk, nextoff);
1121 				goto abort;
1122 			}
1123 		}
1124 
1125 		if (*bh) {
1126 			map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1127 		} else {
1128 			*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1129 			if (!*bh)
1130 				goto abort;
1131 		}
1132 		bh++;	/* Next buffer head */
1133 		b_off++;	/* Next buffer offset */
1134 		nblocks--;
1135 		rv++;
1136 	}
1137 
1138 	error = 0;
1139 abort:
1140 	return rv != 0 ? rv : error;
1141 }
1142 
1143 /*
1144  * Used by the standard interfaces.
1145  */
1146 static int isofs_get_block(struct inode *inode, sector_t iblock,
1147 		    struct buffer_head *bh_result, int create)
1148 {
1149 	int ret;
1150 
1151 	if (create) {
1152 		printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1153 		return -EROFS;
1154 	}
1155 
1156 	ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1157 	return ret < 0 ? ret : 0;
1158 }
1159 
1160 static int isofs_bmap(struct inode *inode, sector_t block)
1161 {
1162 	struct buffer_head dummy;
1163 	int error;
1164 
1165 	dummy.b_state = 0;
1166 	dummy.b_blocknr = -1000;
1167 	error = isofs_get_block(inode, block, &dummy, 0);
1168 	if (!error)
1169 		return dummy.b_blocknr;
1170 	return 0;
1171 }
1172 
1173 struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1174 {
1175 	sector_t blknr = isofs_bmap(inode, block);
1176 	if (!blknr)
1177 		return NULL;
1178 	return sb_bread(inode->i_sb, blknr);
1179 }
1180 
1181 static int isofs_readpage(struct file *file, struct page *page)
1182 {
1183 	return mpage_readpage(page, isofs_get_block);
1184 }
1185 
1186 static int isofs_readpages(struct file *file, struct address_space *mapping,
1187 			struct list_head *pages, unsigned nr_pages)
1188 {
1189 	return mpage_readpages(mapping, pages, nr_pages, isofs_get_block);
1190 }
1191 
1192 static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1193 {
1194 	return generic_block_bmap(mapping,block,isofs_get_block);
1195 }
1196 
1197 static const struct address_space_operations isofs_aops = {
1198 	.readpage = isofs_readpage,
1199 	.readpages = isofs_readpages,
1200 	.bmap = _isofs_bmap
1201 };
1202 
1203 static int isofs_read_level3_size(struct inode *inode)
1204 {
1205 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1206 	int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1207 	struct buffer_head *bh = NULL;
1208 	unsigned long block, offset, block_saved, offset_saved;
1209 	int i = 0;
1210 	int more_entries = 0;
1211 	struct iso_directory_record *tmpde = NULL;
1212 	struct iso_inode_info *ei = ISOFS_I(inode);
1213 
1214 	inode->i_size = 0;
1215 
1216 	/* The first 16 blocks are reserved as the System Area.  Thus,
1217 	 * no inodes can appear in block 0.  We use this to flag that
1218 	 * this is the last section. */
1219 	ei->i_next_section_block = 0;
1220 	ei->i_next_section_offset = 0;
1221 
1222 	block = ei->i_iget5_block;
1223 	offset = ei->i_iget5_offset;
1224 
1225 	do {
1226 		struct iso_directory_record *de;
1227 		unsigned int de_len;
1228 
1229 		if (!bh) {
1230 			bh = sb_bread(inode->i_sb, block);
1231 			if (!bh)
1232 				goto out_noread;
1233 		}
1234 		de = (struct iso_directory_record *) (bh->b_data + offset);
1235 		de_len = *(unsigned char *) de;
1236 
1237 		if (de_len == 0) {
1238 			brelse(bh);
1239 			bh = NULL;
1240 			++block;
1241 			offset = 0;
1242 			continue;
1243 		}
1244 
1245 		block_saved = block;
1246 		offset_saved = offset;
1247 		offset += de_len;
1248 
1249 		/* Make sure we have a full directory entry */
1250 		if (offset >= bufsize) {
1251 			int slop = bufsize - offset + de_len;
1252 			if (!tmpde) {
1253 				tmpde = kmalloc(256, GFP_KERNEL);
1254 				if (!tmpde)
1255 					goto out_nomem;
1256 			}
1257 			memcpy(tmpde, de, slop);
1258 			offset &= bufsize - 1;
1259 			block++;
1260 			brelse(bh);
1261 			bh = NULL;
1262 			if (offset) {
1263 				bh = sb_bread(inode->i_sb, block);
1264 				if (!bh)
1265 					goto out_noread;
1266 				memcpy((void *)tmpde+slop, bh->b_data, offset);
1267 			}
1268 			de = tmpde;
1269 		}
1270 
1271 		inode->i_size += isonum_733(de->size);
1272 		if (i == 1) {
1273 			ei->i_next_section_block = block_saved;
1274 			ei->i_next_section_offset = offset_saved;
1275 		}
1276 
1277 		more_entries = de->flags[-high_sierra] & 0x80;
1278 
1279 		i++;
1280 		if (i > 100)
1281 			goto out_toomany;
1282 	} while (more_entries);
1283 out:
1284 	kfree(tmpde);
1285 	if (bh)
1286 		brelse(bh);
1287 	return 0;
1288 
1289 out_nomem:
1290 	if (bh)
1291 		brelse(bh);
1292 	return -ENOMEM;
1293 
1294 out_noread:
1295 	printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1296 	kfree(tmpde);
1297 	return -EIO;
1298 
1299 out_toomany:
1300 	printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1301 		"isofs_read_level3_size: inode=%lu\n",
1302 		__func__, inode->i_ino);
1303 	goto out;
1304 }
1305 
1306 static int isofs_read_inode(struct inode *inode, int relocated)
1307 {
1308 	struct super_block *sb = inode->i_sb;
1309 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
1310 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1311 	unsigned long block;
1312 	int high_sierra = sbi->s_high_sierra;
1313 	struct buffer_head *bh;
1314 	struct iso_directory_record *de;
1315 	struct iso_directory_record *tmpde = NULL;
1316 	unsigned int de_len;
1317 	unsigned long offset;
1318 	struct iso_inode_info *ei = ISOFS_I(inode);
1319 	int ret = -EIO;
1320 
1321 	block = ei->i_iget5_block;
1322 	bh = sb_bread(inode->i_sb, block);
1323 	if (!bh)
1324 		goto out_badread;
1325 
1326 	offset = ei->i_iget5_offset;
1327 
1328 	de = (struct iso_directory_record *) (bh->b_data + offset);
1329 	de_len = *(unsigned char *) de;
1330 
1331 	if (offset + de_len > bufsize) {
1332 		int frag1 = bufsize - offset;
1333 
1334 		tmpde = kmalloc(de_len, GFP_KERNEL);
1335 		if (!tmpde) {
1336 			ret = -ENOMEM;
1337 			goto fail;
1338 		}
1339 		memcpy(tmpde, bh->b_data + offset, frag1);
1340 		brelse(bh);
1341 		bh = sb_bread(inode->i_sb, ++block);
1342 		if (!bh)
1343 			goto out_badread;
1344 		memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1345 		de = tmpde;
1346 	}
1347 
1348 	inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1349 					ei->i_iget5_offset,
1350 					ISOFS_BUFFER_BITS(inode));
1351 
1352 	/* Assume it is a normal-format file unless told otherwise */
1353 	ei->i_file_format = isofs_file_normal;
1354 
1355 	if (de->flags[-high_sierra] & 2) {
1356 		if (sbi->s_dmode != ISOFS_INVALID_MODE)
1357 			inode->i_mode = S_IFDIR | sbi->s_dmode;
1358 		else
1359 			inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1360 		set_nlink(inode, 1);	/*
1361 					 * Set to 1.  We know there are 2, but
1362 					 * the find utility tries to optimize
1363 					 * if it is 2, and it screws up.  It is
1364 					 * easier to give 1 which tells find to
1365 					 * do it the hard way.
1366 					 */
1367 	} else {
1368 		if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1369 			inode->i_mode = S_IFREG | sbi->s_fmode;
1370 		} else {
1371 			/*
1372 			 * Set default permissions: r-x for all.  The disc
1373 			 * could be shared with DOS machines so virtually
1374 			 * anything could be a valid executable.
1375 			 */
1376 			inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1377 		}
1378 		set_nlink(inode, 1);
1379 	}
1380 	inode->i_uid = sbi->s_uid;
1381 	inode->i_gid = sbi->s_gid;
1382 	inode->i_blocks = 0;
1383 
1384 	ei->i_format_parm[0] = 0;
1385 	ei->i_format_parm[1] = 0;
1386 	ei->i_format_parm[2] = 0;
1387 
1388 	ei->i_section_size = isonum_733(de->size);
1389 	if (de->flags[-high_sierra] & 0x80) {
1390 		ret = isofs_read_level3_size(inode);
1391 		if (ret < 0)
1392 			goto fail;
1393 		ret = -EIO;
1394 	} else {
1395 		ei->i_next_section_block = 0;
1396 		ei->i_next_section_offset = 0;
1397 		inode->i_size = isonum_733(de->size);
1398 	}
1399 
1400 	/*
1401 	 * Some dipshit decided to store some other bit of information
1402 	 * in the high byte of the file length.  Truncate size in case
1403 	 * this CDROM was mounted with the cruft option.
1404 	 */
1405 
1406 	if (sbi->s_cruft)
1407 		inode->i_size &= 0x00ffffff;
1408 
1409 	if (de->interleave[0]) {
1410 		printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1411 		inode->i_size = 0;
1412 	}
1413 
1414 	/* I have no idea what file_unit_size is used for, so
1415 	   we will flag it for now */
1416 	if (de->file_unit_size[0] != 0) {
1417 		printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1418 			inode->i_ino);
1419 	}
1420 
1421 	/* I have no idea what other flag bits are used for, so
1422 	   we will flag it for now */
1423 #ifdef DEBUG
1424 	if((de->flags[-high_sierra] & ~2)!= 0){
1425 		printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1426 				"(%ld %x).\n",
1427 			inode->i_ino, de->flags[-high_sierra]);
1428 	}
1429 #endif
1430 
1431 	inode->i_mtime.tv_sec =
1432 	inode->i_atime.tv_sec =
1433 	inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
1434 	inode->i_mtime.tv_nsec =
1435 	inode->i_atime.tv_nsec =
1436 	inode->i_ctime.tv_nsec = 0;
1437 
1438 	ei->i_first_extent = (isonum_733(de->extent) +
1439 			isonum_711(de->ext_attr_length));
1440 
1441 	/* Set the number of blocks for stat() - should be done before RR */
1442 	inode->i_blocks = (inode->i_size + 511) >> 9;
1443 
1444 	/*
1445 	 * Now test for possible Rock Ridge extensions which will override
1446 	 * some of these numbers in the inode structure.
1447 	 */
1448 
1449 	if (!high_sierra) {
1450 		parse_rock_ridge_inode(de, inode, relocated);
1451 		/* if we want uid/gid set, override the rock ridge setting */
1452 		if (sbi->s_uid_set)
1453 			inode->i_uid = sbi->s_uid;
1454 		if (sbi->s_gid_set)
1455 			inode->i_gid = sbi->s_gid;
1456 	}
1457 	/* Now set final access rights if overriding rock ridge setting */
1458 	if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1459 	    sbi->s_dmode != ISOFS_INVALID_MODE)
1460 		inode->i_mode = S_IFDIR | sbi->s_dmode;
1461 	if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1462 	    sbi->s_fmode != ISOFS_INVALID_MODE)
1463 		inode->i_mode = S_IFREG | sbi->s_fmode;
1464 
1465 	/* Install the inode operations vector */
1466 	if (S_ISREG(inode->i_mode)) {
1467 		inode->i_fop = &generic_ro_fops;
1468 		switch (ei->i_file_format) {
1469 #ifdef CONFIG_ZISOFS
1470 		case isofs_file_compressed:
1471 			inode->i_data.a_ops = &zisofs_aops;
1472 			break;
1473 #endif
1474 		default:
1475 			inode->i_data.a_ops = &isofs_aops;
1476 			break;
1477 		}
1478 	} else if (S_ISDIR(inode->i_mode)) {
1479 		inode->i_op = &isofs_dir_inode_operations;
1480 		inode->i_fop = &isofs_dir_operations;
1481 	} else if (S_ISLNK(inode->i_mode)) {
1482 		inode->i_op = &page_symlink_inode_operations;
1483 		inode_nohighmem(inode);
1484 		inode->i_data.a_ops = &isofs_symlink_aops;
1485 	} else
1486 		/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1487 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1488 
1489 	ret = 0;
1490 out:
1491 	kfree(tmpde);
1492 	if (bh)
1493 		brelse(bh);
1494 	return ret;
1495 
1496 out_badread:
1497 	printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1498 fail:
1499 	goto out;
1500 }
1501 
1502 struct isofs_iget5_callback_data {
1503 	unsigned long block;
1504 	unsigned long offset;
1505 };
1506 
1507 static int isofs_iget5_test(struct inode *ino, void *data)
1508 {
1509 	struct iso_inode_info *i = ISOFS_I(ino);
1510 	struct isofs_iget5_callback_data *d =
1511 		(struct isofs_iget5_callback_data*)data;
1512 	return (i->i_iget5_block == d->block)
1513 		&& (i->i_iget5_offset == d->offset);
1514 }
1515 
1516 static int isofs_iget5_set(struct inode *ino, void *data)
1517 {
1518 	struct iso_inode_info *i = ISOFS_I(ino);
1519 	struct isofs_iget5_callback_data *d =
1520 		(struct isofs_iget5_callback_data*)data;
1521 	i->i_iget5_block = d->block;
1522 	i->i_iget5_offset = d->offset;
1523 	return 0;
1524 }
1525 
1526 /* Store, in the inode's containing structure, the block and block
1527  * offset that point to the underlying meta-data for the inode.  The
1528  * code below is otherwise similar to the iget() code in
1529  * include/linux/fs.h */
1530 struct inode *__isofs_iget(struct super_block *sb,
1531 			   unsigned long block,
1532 			   unsigned long offset,
1533 			   int relocated)
1534 {
1535 	unsigned long hashval;
1536 	struct inode *inode;
1537 	struct isofs_iget5_callback_data data;
1538 	long ret;
1539 
1540 	if (offset >= 1ul << sb->s_blocksize_bits)
1541 		return ERR_PTR(-EINVAL);
1542 
1543 	data.block = block;
1544 	data.offset = offset;
1545 
1546 	hashval = (block << sb->s_blocksize_bits) | offset;
1547 
1548 	inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1549 				&isofs_iget5_set, &data);
1550 
1551 	if (!inode)
1552 		return ERR_PTR(-ENOMEM);
1553 
1554 	if (inode->i_state & I_NEW) {
1555 		ret = isofs_read_inode(inode, relocated);
1556 		if (ret < 0) {
1557 			iget_failed(inode);
1558 			inode = ERR_PTR(ret);
1559 		} else {
1560 			unlock_new_inode(inode);
1561 		}
1562 	}
1563 
1564 	return inode;
1565 }
1566 
1567 static struct dentry *isofs_mount(struct file_system_type *fs_type,
1568 	int flags, const char *dev_name, void *data)
1569 {
1570 	return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1571 }
1572 
1573 static struct file_system_type iso9660_fs_type = {
1574 	.owner		= THIS_MODULE,
1575 	.name		= "iso9660",
1576 	.mount		= isofs_mount,
1577 	.kill_sb	= kill_block_super,
1578 	.fs_flags	= FS_REQUIRES_DEV,
1579 };
1580 MODULE_ALIAS_FS("iso9660");
1581 MODULE_ALIAS("iso9660");
1582 
1583 static int __init init_iso9660_fs(void)
1584 {
1585 	int err = init_inodecache();
1586 	if (err)
1587 		goto out;
1588 #ifdef CONFIG_ZISOFS
1589 	err = zisofs_init();
1590 	if (err)
1591 		goto out1;
1592 #endif
1593 	err = register_filesystem(&iso9660_fs_type);
1594 	if (err)
1595 		goto out2;
1596 	return 0;
1597 out2:
1598 #ifdef CONFIG_ZISOFS
1599 	zisofs_cleanup();
1600 out1:
1601 #endif
1602 	destroy_inodecache();
1603 out:
1604 	return err;
1605 }
1606 
1607 static void __exit exit_iso9660_fs(void)
1608 {
1609         unregister_filesystem(&iso9660_fs_type);
1610 #ifdef CONFIG_ZISOFS
1611 	zisofs_cleanup();
1612 #endif
1613 	destroy_inodecache();
1614 }
1615 
1616 module_init(init_iso9660_fs)
1617 module_exit(exit_iso9660_fs)
1618 MODULE_LICENSE("GPL");
1619