xref: /openbmc/linux/fs/isofs/inode.c (revision 5e012745)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/fs/isofs/inode.c
4  *
5  *  (C) 1991  Linus Torvalds - minix filesystem
6  *      1992, 1993, 1994  Eric Youngdale Modified for ISO 9660 filesystem.
7  *      1994  Eberhard Mönkeberg - multi session handling.
8  *      1995  Mark Dobie - allow mounting of some weird VideoCDs and PhotoCDs.
9  *	1997  Gordon Chaffee - Joliet CDs
10  *	1998  Eric Lammerts - ISO 9660 Level 3
11  *	2004  Paul Serice - Inode Support pushed out from 4GB to 128GB
12  *	2004  Paul Serice - NFS Export Operations
13  */
14 
15 #include <linux/init.h>
16 #include <linux/module.h>
17 
18 #include <linux/slab.h>
19 #include <linux/cred.h>
20 #include <linux/nls.h>
21 #include <linux/ctype.h>
22 #include <linux/statfs.h>
23 #include <linux/cdrom.h>
24 #include <linux/parser.h>
25 #include <linux/mpage.h>
26 #include <linux/user_namespace.h>
27 #include <linux/seq_file.h>
28 #include <linux/blkdev.h>
29 
30 #include "isofs.h"
31 #include "zisofs.h"
32 
33 #define BEQUIET
34 
35 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
36 static int isofs_dentry_cmpi(const struct dentry *dentry,
37 		unsigned int len, const char *str, const struct qstr *name);
38 
39 #ifdef CONFIG_JOLIET
40 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
41 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
42 static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
43 		unsigned int len, const char *str, const struct qstr *name);
44 static int isofs_dentry_cmp_ms(const struct dentry *dentry,
45 		unsigned int len, const char *str, const struct qstr *name);
46 #endif
47 
48 static void isofs_put_super(struct super_block *sb)
49 {
50 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
51 
52 #ifdef CONFIG_JOLIET
53 	unload_nls(sbi->s_nls_iocharset);
54 #endif
55 
56 	kfree(sbi);
57 	sb->s_fs_info = NULL;
58 	return;
59 }
60 
61 static int isofs_read_inode(struct inode *, int relocated);
62 static int isofs_statfs (struct dentry *, struct kstatfs *);
63 static int isofs_show_options(struct seq_file *, struct dentry *);
64 
65 static struct kmem_cache *isofs_inode_cachep;
66 
67 static struct inode *isofs_alloc_inode(struct super_block *sb)
68 {
69 	struct iso_inode_info *ei;
70 	ei = kmem_cache_alloc(isofs_inode_cachep, GFP_KERNEL);
71 	if (!ei)
72 		return NULL;
73 	return &ei->vfs_inode;
74 }
75 
76 static void isofs_free_inode(struct inode *inode)
77 {
78 	kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
79 }
80 
81 static void init_once(void *foo)
82 {
83 	struct iso_inode_info *ei = foo;
84 
85 	inode_init_once(&ei->vfs_inode);
86 }
87 
88 static int __init init_inodecache(void)
89 {
90 	isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
91 					sizeof(struct iso_inode_info),
92 					0, (SLAB_RECLAIM_ACCOUNT|
93 					SLAB_MEM_SPREAD|SLAB_ACCOUNT),
94 					init_once);
95 	if (!isofs_inode_cachep)
96 		return -ENOMEM;
97 	return 0;
98 }
99 
100 static void destroy_inodecache(void)
101 {
102 	/*
103 	 * Make sure all delayed rcu free inodes are flushed before we
104 	 * destroy cache.
105 	 */
106 	rcu_barrier();
107 	kmem_cache_destroy(isofs_inode_cachep);
108 }
109 
110 static int isofs_remount(struct super_block *sb, int *flags, char *data)
111 {
112 	sync_filesystem(sb);
113 	if (!(*flags & SB_RDONLY))
114 		return -EROFS;
115 	return 0;
116 }
117 
118 static const struct super_operations isofs_sops = {
119 	.alloc_inode	= isofs_alloc_inode,
120 	.free_inode	= isofs_free_inode,
121 	.put_super	= isofs_put_super,
122 	.statfs		= isofs_statfs,
123 	.remount_fs	= isofs_remount,
124 	.show_options	= isofs_show_options,
125 };
126 
127 
128 static const struct dentry_operations isofs_dentry_ops[] = {
129 	{
130 		.d_hash		= isofs_hashi,
131 		.d_compare	= isofs_dentry_cmpi,
132 	},
133 #ifdef CONFIG_JOLIET
134 	{
135 		.d_hash		= isofs_hash_ms,
136 		.d_compare	= isofs_dentry_cmp_ms,
137 	},
138 	{
139 		.d_hash		= isofs_hashi_ms,
140 		.d_compare	= isofs_dentry_cmpi_ms,
141 	},
142 #endif
143 };
144 
145 struct iso9660_options{
146 	unsigned int rock:1;
147 	unsigned int joliet:1;
148 	unsigned int cruft:1;
149 	unsigned int hide:1;
150 	unsigned int showassoc:1;
151 	unsigned int nocompress:1;
152 	unsigned int overriderockperm:1;
153 	unsigned int uid_set:1;
154 	unsigned int gid_set:1;
155 	unsigned int utf8:1;
156 	unsigned char map;
157 	unsigned char check;
158 	unsigned int blocksize;
159 	umode_t fmode;
160 	umode_t dmode;
161 	kgid_t gid;
162 	kuid_t uid;
163 	char *iocharset;
164 	/* LVE */
165 	s32 session;
166 	s32 sbsector;
167 };
168 
169 /*
170  * Compute the hash for the isofs name corresponding to the dentry.
171  */
172 static int
173 isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
174 {
175 	const char *name;
176 	int len;
177 	char c;
178 	unsigned long hash;
179 
180 	len = qstr->len;
181 	name = qstr->name;
182 	if (ms) {
183 		while (len && name[len-1] == '.')
184 			len--;
185 	}
186 
187 	hash = init_name_hash(dentry);
188 	while (len--) {
189 		c = tolower(*name++);
190 		hash = partial_name_hash(c, hash);
191 	}
192 	qstr->hash = end_name_hash(hash);
193 
194 	return 0;
195 }
196 
197 /*
198  * Compare of two isofs names.
199  */
200 static int isofs_dentry_cmp_common(
201 		unsigned int len, const char *str,
202 		const struct qstr *name, int ms, int ci)
203 {
204 	int alen, blen;
205 
206 	/* A filename cannot end in '.' or we treat it like it has none */
207 	alen = name->len;
208 	blen = len;
209 	if (ms) {
210 		while (alen && name->name[alen-1] == '.')
211 			alen--;
212 		while (blen && str[blen-1] == '.')
213 			blen--;
214 	}
215 	if (alen == blen) {
216 		if (ci) {
217 			if (strncasecmp(name->name, str, alen) == 0)
218 				return 0;
219 		} else {
220 			if (strncmp(name->name, str, alen) == 0)
221 				return 0;
222 		}
223 	}
224 	return 1;
225 }
226 
227 static int
228 isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
229 {
230 	return isofs_hashi_common(dentry, qstr, 0);
231 }
232 
233 static int
234 isofs_dentry_cmpi(const struct dentry *dentry,
235 		unsigned int len, const char *str, const struct qstr *name)
236 {
237 	return isofs_dentry_cmp_common(len, str, name, 0, 1);
238 }
239 
240 #ifdef CONFIG_JOLIET
241 /*
242  * Compute the hash for the isofs name corresponding to the dentry.
243  */
244 static int
245 isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
246 {
247 	const char *name;
248 	int len;
249 
250 	len = qstr->len;
251 	name = qstr->name;
252 	if (ms) {
253 		while (len && name[len-1] == '.')
254 			len--;
255 	}
256 
257 	qstr->hash = full_name_hash(dentry, name, len);
258 
259 	return 0;
260 }
261 
262 static int
263 isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
264 {
265 	return isofs_hash_common(dentry, qstr, 1);
266 }
267 
268 static int
269 isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
270 {
271 	return isofs_hashi_common(dentry, qstr, 1);
272 }
273 
274 static int
275 isofs_dentry_cmp_ms(const struct dentry *dentry,
276 		unsigned int len, const char *str, const struct qstr *name)
277 {
278 	return isofs_dentry_cmp_common(len, str, name, 1, 0);
279 }
280 
281 static int
282 isofs_dentry_cmpi_ms(const struct dentry *dentry,
283 		unsigned int len, const char *str, const struct qstr *name)
284 {
285 	return isofs_dentry_cmp_common(len, str, name, 1, 1);
286 }
287 #endif
288 
289 enum {
290 	Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
291 	Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
292 	Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
293 	Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
294 };
295 
296 static const match_table_t tokens = {
297 	{Opt_norock, "norock"},
298 	{Opt_nojoliet, "nojoliet"},
299 	{Opt_unhide, "unhide"},
300 	{Opt_hide, "hide"},
301 	{Opt_showassoc, "showassoc"},
302 	{Opt_cruft, "cruft"},
303 	{Opt_utf8, "utf8"},
304 	{Opt_iocharset, "iocharset=%s"},
305 	{Opt_map_a, "map=acorn"},
306 	{Opt_map_a, "map=a"},
307 	{Opt_map_n, "map=normal"},
308 	{Opt_map_n, "map=n"},
309 	{Opt_map_o, "map=off"},
310 	{Opt_map_o, "map=o"},
311 	{Opt_session, "session=%u"},
312 	{Opt_sb, "sbsector=%u"},
313 	{Opt_check_r, "check=relaxed"},
314 	{Opt_check_r, "check=r"},
315 	{Opt_check_s, "check=strict"},
316 	{Opt_check_s, "check=s"},
317 	{Opt_uid, "uid=%u"},
318 	{Opt_gid, "gid=%u"},
319 	{Opt_mode, "mode=%u"},
320 	{Opt_dmode, "dmode=%u"},
321 	{Opt_overriderockperm, "overriderockperm"},
322 	{Opt_block, "block=%u"},
323 	{Opt_ignore, "conv=binary"},
324 	{Opt_ignore, "conv=b"},
325 	{Opt_ignore, "conv=text"},
326 	{Opt_ignore, "conv=t"},
327 	{Opt_ignore, "conv=mtext"},
328 	{Opt_ignore, "conv=m"},
329 	{Opt_ignore, "conv=auto"},
330 	{Opt_ignore, "conv=a"},
331 	{Opt_nocompress, "nocompress"},
332 	{Opt_err, NULL}
333 };
334 
335 static int parse_options(char *options, struct iso9660_options *popt)
336 {
337 	char *p;
338 	int option;
339 
340 	popt->map = 'n';
341 	popt->rock = 1;
342 	popt->joliet = 1;
343 	popt->cruft = 0;
344 	popt->hide = 0;
345 	popt->showassoc = 0;
346 	popt->check = 'u';		/* unset */
347 	popt->nocompress = 0;
348 	popt->blocksize = 1024;
349 	popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
350 	popt->uid_set = 0;
351 	popt->gid_set = 0;
352 	popt->gid = GLOBAL_ROOT_GID;
353 	popt->uid = GLOBAL_ROOT_UID;
354 	popt->iocharset = NULL;
355 	popt->utf8 = 0;
356 	popt->overriderockperm = 0;
357 	popt->session=-1;
358 	popt->sbsector=-1;
359 	if (!options)
360 		return 1;
361 
362 	while ((p = strsep(&options, ",")) != NULL) {
363 		int token;
364 		substring_t args[MAX_OPT_ARGS];
365 		unsigned n;
366 
367 		if (!*p)
368 			continue;
369 
370 		token = match_token(p, tokens, args);
371 		switch (token) {
372 		case Opt_norock:
373 			popt->rock = 0;
374 			break;
375 		case Opt_nojoliet:
376 			popt->joliet = 0;
377 			break;
378 		case Opt_hide:
379 			popt->hide = 1;
380 			break;
381 		case Opt_unhide:
382 		case Opt_showassoc:
383 			popt->showassoc = 1;
384 			break;
385 		case Opt_cruft:
386 			popt->cruft = 1;
387 			break;
388 		case Opt_utf8:
389 			popt->utf8 = 1;
390 			break;
391 #ifdef CONFIG_JOLIET
392 		case Opt_iocharset:
393 			kfree(popt->iocharset);
394 			popt->iocharset = match_strdup(&args[0]);
395 			if (!popt->iocharset)
396 				return 0;
397 			break;
398 #endif
399 		case Opt_map_a:
400 			popt->map = 'a';
401 			break;
402 		case Opt_map_o:
403 			popt->map = 'o';
404 			break;
405 		case Opt_map_n:
406 			popt->map = 'n';
407 			break;
408 		case Opt_session:
409 			if (match_int(&args[0], &option))
410 				return 0;
411 			n = option;
412 			/*
413 			 * Track numbers are supposed to be in range 1-99, the
414 			 * mount option starts indexing at 0.
415 			 */
416 			if (n >= 99)
417 				return 0;
418 			popt->session = n + 1;
419 			break;
420 		case Opt_sb:
421 			if (match_int(&args[0], &option))
422 				return 0;
423 			popt->sbsector = option;
424 			break;
425 		case Opt_check_r:
426 			popt->check = 'r';
427 			break;
428 		case Opt_check_s:
429 			popt->check = 's';
430 			break;
431 		case Opt_ignore:
432 			break;
433 		case Opt_uid:
434 			if (match_int(&args[0], &option))
435 				return 0;
436 			popt->uid = make_kuid(current_user_ns(), option);
437 			if (!uid_valid(popt->uid))
438 				return 0;
439 			popt->uid_set = 1;
440 			break;
441 		case Opt_gid:
442 			if (match_int(&args[0], &option))
443 				return 0;
444 			popt->gid = make_kgid(current_user_ns(), option);
445 			if (!gid_valid(popt->gid))
446 				return 0;
447 			popt->gid_set = 1;
448 			break;
449 		case Opt_mode:
450 			if (match_int(&args[0], &option))
451 				return 0;
452 			popt->fmode = option;
453 			break;
454 		case Opt_dmode:
455 			if (match_int(&args[0], &option))
456 				return 0;
457 			popt->dmode = option;
458 			break;
459 		case Opt_overriderockperm:
460 			popt->overriderockperm = 1;
461 			break;
462 		case Opt_block:
463 			if (match_int(&args[0], &option))
464 				return 0;
465 			n = option;
466 			if (n != 512 && n != 1024 && n != 2048)
467 				return 0;
468 			popt->blocksize = n;
469 			break;
470 		case Opt_nocompress:
471 			popt->nocompress = 1;
472 			break;
473 		default:
474 			return 0;
475 		}
476 	}
477 	return 1;
478 }
479 
480 /*
481  * Display the mount options in /proc/mounts.
482  */
483 static int isofs_show_options(struct seq_file *m, struct dentry *root)
484 {
485 	struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
486 
487 	if (!sbi->s_rock)		seq_puts(m, ",norock");
488 	else if (!sbi->s_joliet_level)	seq_puts(m, ",nojoliet");
489 	if (sbi->s_cruft)		seq_puts(m, ",cruft");
490 	if (sbi->s_hide)		seq_puts(m, ",hide");
491 	if (sbi->s_nocompress)		seq_puts(m, ",nocompress");
492 	if (sbi->s_overriderockperm)	seq_puts(m, ",overriderockperm");
493 	if (sbi->s_showassoc)		seq_puts(m, ",showassoc");
494 	if (sbi->s_utf8)		seq_puts(m, ",utf8");
495 
496 	if (sbi->s_check)		seq_printf(m, ",check=%c", sbi->s_check);
497 	if (sbi->s_mapping)		seq_printf(m, ",map=%c", sbi->s_mapping);
498 	if (sbi->s_session != 255)	seq_printf(m, ",session=%u", sbi->s_session - 1);
499 	if (sbi->s_sbsector != -1)	seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
500 
501 	if (root->d_sb->s_blocksize != 1024)
502 		seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
503 
504 	if (sbi->s_uid_set)
505 		seq_printf(m, ",uid=%u",
506 			   from_kuid_munged(&init_user_ns, sbi->s_uid));
507 	if (sbi->s_gid_set)
508 		seq_printf(m, ",gid=%u",
509 			   from_kgid_munged(&init_user_ns, sbi->s_gid));
510 
511 	if (sbi->s_dmode != ISOFS_INVALID_MODE)
512 		seq_printf(m, ",dmode=%o", sbi->s_dmode);
513 	if (sbi->s_fmode != ISOFS_INVALID_MODE)
514 		seq_printf(m, ",fmode=%o", sbi->s_fmode);
515 
516 #ifdef CONFIG_JOLIET
517 	if (sbi->s_nls_iocharset &&
518 	    strcmp(sbi->s_nls_iocharset->charset, CONFIG_NLS_DEFAULT) != 0)
519 		seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
520 #endif
521 	return 0;
522 }
523 
524 /*
525  * look if the driver can tell the multi session redirection value
526  *
527  * don't change this if you don't know what you do, please!
528  * Multisession is legal only with XA disks.
529  * A non-XA disk with more than one volume descriptor may do it right, but
530  * usually is written in a nowhere standardized "multi-partition" manner.
531  * Multisession uses absolute addressing (solely the first frame of the whole
532  * track is #0), multi-partition uses relative addressing (each first frame of
533  * each track is #0), and a track is not a session.
534  *
535  * A broken CDwriter software or drive firmware does not set new standards,
536  * at least not if conflicting with the existing ones.
537  *
538  * emoenke@gwdg.de
539  */
540 #define WE_OBEY_THE_WRITTEN_STANDARDS 1
541 
542 static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
543 {
544 	struct cdrom_multisession ms_info;
545 	unsigned int vol_desc_start;
546 	struct block_device *bdev = sb->s_bdev;
547 	int i;
548 
549 	vol_desc_start=0;
550 	ms_info.addr_format=CDROM_LBA;
551 	if (session > 0) {
552 		struct cdrom_tocentry Te;
553 		Te.cdte_track=session;
554 		Te.cdte_format=CDROM_LBA;
555 		i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
556 		if (!i) {
557 			printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
558 				session, Te.cdte_addr.lba,
559 				Te.cdte_ctrl&CDROM_DATA_TRACK);
560 			if ((Te.cdte_ctrl&CDROM_DATA_TRACK) == 4)
561 				return Te.cdte_addr.lba;
562 		}
563 
564 		printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
565 	}
566 	i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long) &ms_info);
567 	if (session > 0)
568 		printk(KERN_ERR "ISOFS: Invalid session number\n");
569 #if 0
570 	printk(KERN_DEBUG "isofs.inode: CDROMMULTISESSION: rc=%d\n",i);
571 	if (i==0) {
572 		printk(KERN_DEBUG "isofs.inode: XA disk: %s\n",ms_info.xa_flag?"yes":"no");
573 		printk(KERN_DEBUG "isofs.inode: vol_desc_start = %d\n", ms_info.addr.lba);
574 	}
575 #endif
576 	if (i==0)
577 #if WE_OBEY_THE_WRITTEN_STANDARDS
578 		if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
579 #endif
580 			vol_desc_start=ms_info.addr.lba;
581 	return vol_desc_start;
582 }
583 
584 /*
585  * Check if root directory is empty (has less than 3 files).
586  *
587  * Used to detect broken CDs where ISO root directory is empty but Joliet root
588  * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
589  * (and Joliet used instead) or else no files would be visible.
590  */
591 static bool rootdir_empty(struct super_block *sb, unsigned long block)
592 {
593 	int offset = 0, files = 0, de_len;
594 	struct iso_directory_record *de;
595 	struct buffer_head *bh;
596 
597 	bh = sb_bread(sb, block);
598 	if (!bh)
599 		return true;
600 	while (files < 3) {
601 		de = (struct iso_directory_record *) (bh->b_data + offset);
602 		de_len = *(unsigned char *) de;
603 		if (de_len == 0)
604 			break;
605 		files++;
606 		offset += de_len;
607 	}
608 	brelse(bh);
609 	return files < 3;
610 }
611 
612 /*
613  * Initialize the superblock and read the root inode.
614  *
615  * Note: a check_disk_change() has been done immediately prior
616  * to this call, so we don't need to check again.
617  */
618 static int isofs_fill_super(struct super_block *s, void *data, int silent)
619 {
620 	struct buffer_head *bh = NULL, *pri_bh = NULL;
621 	struct hs_primary_descriptor *h_pri = NULL;
622 	struct iso_primary_descriptor *pri = NULL;
623 	struct iso_supplementary_descriptor *sec = NULL;
624 	struct iso_directory_record *rootp;
625 	struct inode *inode;
626 	struct iso9660_options opt;
627 	struct isofs_sb_info *sbi;
628 	unsigned long first_data_zone;
629 	int joliet_level = 0;
630 	int iso_blknum, block;
631 	int orig_zonesize;
632 	int table, error = -EINVAL;
633 	unsigned int vol_desc_start;
634 
635 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
636 	if (!sbi)
637 		return -ENOMEM;
638 	s->s_fs_info = sbi;
639 
640 	if (!parse_options((char *)data, &opt))
641 		goto out_freesbi;
642 
643 	/*
644 	 * First of all, get the hardware blocksize for this device.
645 	 * If we don't know what it is, or the hardware blocksize is
646 	 * larger than the blocksize the user specified, then use
647 	 * that value.
648 	 */
649 	/*
650 	 * What if bugger tells us to go beyond page size?
651 	 */
652 	if (bdev_logical_block_size(s->s_bdev) > 2048) {
653 		printk(KERN_WARNING
654 		       "ISOFS: unsupported/invalid hardware sector size %d\n",
655 			bdev_logical_block_size(s->s_bdev));
656 		goto out_freesbi;
657 	}
658 	opt.blocksize = sb_min_blocksize(s, opt.blocksize);
659 
660 	sbi->s_high_sierra = 0; /* default is iso9660 */
661 	sbi->s_session = opt.session;
662 	sbi->s_sbsector = opt.sbsector;
663 
664 	vol_desc_start = (opt.sbsector != -1) ?
665 		opt.sbsector : isofs_get_last_session(s,opt.session);
666 
667 	for (iso_blknum = vol_desc_start+16;
668 		iso_blknum < vol_desc_start+100; iso_blknum++) {
669 		struct hs_volume_descriptor *hdp;
670 		struct iso_volume_descriptor  *vdp;
671 
672 		block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
673 		if (!(bh = sb_bread(s, block)))
674 			goto out_no_read;
675 
676 		vdp = (struct iso_volume_descriptor *)bh->b_data;
677 		hdp = (struct hs_volume_descriptor *)bh->b_data;
678 
679 		/*
680 		 * Due to the overlapping physical location of the descriptors,
681 		 * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
682 		 * proper identification in this case, we first check for ISO.
683 		 */
684 		if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
685 			if (isonum_711(vdp->type) == ISO_VD_END)
686 				break;
687 			if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
688 				if (!pri) {
689 					pri = (struct iso_primary_descriptor *)vdp;
690 					/* Save the buffer in case we need it ... */
691 					pri_bh = bh;
692 					bh = NULL;
693 				}
694 			}
695 #ifdef CONFIG_JOLIET
696 			else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
697 				sec = (struct iso_supplementary_descriptor *)vdp;
698 				if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
699 					if (opt.joliet) {
700 						if (sec->escape[2] == 0x40)
701 							joliet_level = 1;
702 						else if (sec->escape[2] == 0x43)
703 							joliet_level = 2;
704 						else if (sec->escape[2] == 0x45)
705 							joliet_level = 3;
706 
707 						printk(KERN_DEBUG "ISO 9660 Extensions: "
708 							"Microsoft Joliet Level %d\n",
709 							joliet_level);
710 					}
711 					goto root_found;
712 				} else {
713 				/* Unknown supplementary volume descriptor */
714 				sec = NULL;
715 				}
716 			}
717 #endif
718 		} else {
719 			if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
720 				if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
721 					goto out_freebh;
722 
723 				sbi->s_high_sierra = 1;
724 				opt.rock = 0;
725 				h_pri = (struct hs_primary_descriptor *)vdp;
726 				goto root_found;
727 			}
728 		}
729 
730 		/* Just skip any volume descriptors we don't recognize */
731 
732 		brelse(bh);
733 		bh = NULL;
734 	}
735 	/*
736 	 * If we fall through, either no volume descriptor was found,
737 	 * or else we passed a primary descriptor looking for others.
738 	 */
739 	if (!pri)
740 		goto out_unknown_format;
741 	brelse(bh);
742 	bh = pri_bh;
743 	pri_bh = NULL;
744 
745 root_found:
746 	/* We don't support read-write mounts */
747 	if (!sb_rdonly(s)) {
748 		error = -EACCES;
749 		goto out_freebh;
750 	}
751 
752 	if (joliet_level && (!pri || !opt.rock)) {
753 		/* This is the case of Joliet with the norock mount flag.
754 		 * A disc with both Joliet and Rock Ridge is handled later
755 		 */
756 		pri = (struct iso_primary_descriptor *) sec;
757 	}
758 
759 	if(sbi->s_high_sierra){
760 		rootp = (struct iso_directory_record *) h_pri->root_directory_record;
761 		sbi->s_nzones = isonum_733(h_pri->volume_space_size);
762 		sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
763 		sbi->s_max_size = isonum_733(h_pri->volume_space_size);
764 	} else {
765 		if (!pri)
766 			goto out_freebh;
767 		rootp = (struct iso_directory_record *) pri->root_directory_record;
768 		sbi->s_nzones = isonum_733(pri->volume_space_size);
769 		sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
770 		sbi->s_max_size = isonum_733(pri->volume_space_size);
771 	}
772 
773 	sbi->s_ninodes = 0; /* No way to figure this out easily */
774 
775 	orig_zonesize = sbi->s_log_zone_size;
776 	/*
777 	 * If the zone size is smaller than the hardware sector size,
778 	 * this is a fatal error.  This would occur if the disc drive
779 	 * had sectors that were 2048 bytes, but the filesystem had
780 	 * blocks that were 512 bytes (which should only very rarely
781 	 * happen.)
782 	 */
783 	if (orig_zonesize < opt.blocksize)
784 		goto out_bad_size;
785 
786 	/* RDE: convert log zone size to bit shift */
787 	switch (sbi->s_log_zone_size) {
788 	case  512: sbi->s_log_zone_size =  9; break;
789 	case 1024: sbi->s_log_zone_size = 10; break;
790 	case 2048: sbi->s_log_zone_size = 11; break;
791 
792 	default:
793 		goto out_bad_zone_size;
794 	}
795 
796 	s->s_magic = ISOFS_SUPER_MAGIC;
797 
798 	/*
799 	 * With multi-extent files, file size is only limited by the maximum
800 	 * size of a file system, which is 8 TB.
801 	 */
802 	s->s_maxbytes = 0x80000000000LL;
803 
804 	/* Set this for reference. Its not currently used except on write
805 	   which we don't have .. */
806 
807 	first_data_zone = isonum_733(rootp->extent) +
808 			  isonum_711(rootp->ext_attr_length);
809 	sbi->s_firstdatazone = first_data_zone;
810 #ifndef BEQUIET
811 	printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
812 		sbi->s_max_size, 1UL << sbi->s_log_zone_size);
813 	printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
814 	if(sbi->s_high_sierra)
815 		printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
816 #endif
817 
818 	/*
819 	 * If the Joliet level is set, we _may_ decide to use the
820 	 * secondary descriptor, but can't be sure until after we
821 	 * read the root inode. But before reading the root inode
822 	 * we may need to change the device blocksize, and would
823 	 * rather release the old buffer first. So, we cache the
824 	 * first_data_zone value from the secondary descriptor.
825 	 */
826 	if (joliet_level) {
827 		pri = (struct iso_primary_descriptor *) sec;
828 		rootp = (struct iso_directory_record *)
829 			pri->root_directory_record;
830 		first_data_zone = isonum_733(rootp->extent) +
831 				isonum_711(rootp->ext_attr_length);
832 	}
833 
834 	/*
835 	 * We're all done using the volume descriptor, and may need
836 	 * to change the device blocksize, so release the buffer now.
837 	 */
838 	brelse(pri_bh);
839 	brelse(bh);
840 
841 	/*
842 	 * Force the blocksize to 512 for 512 byte sectors.  The file
843 	 * read primitives really get it wrong in a bad way if we don't
844 	 * do this.
845 	 *
846 	 * Note - we should never be setting the blocksize to something
847 	 * less than the hardware sector size for the device.  If we
848 	 * do, we would end up having to read larger buffers and split
849 	 * out portions to satisfy requests.
850 	 *
851 	 * Note2- the idea here is that we want to deal with the optimal
852 	 * zonesize in the filesystem.  If we have it set to something less,
853 	 * then we have horrible problems with trying to piece together
854 	 * bits of adjacent blocks in order to properly read directory
855 	 * entries.  By forcing the blocksize in this way, we ensure
856 	 * that we will never be required to do this.
857 	 */
858 	sb_set_blocksize(s, orig_zonesize);
859 
860 	sbi->s_nls_iocharset = NULL;
861 
862 #ifdef CONFIG_JOLIET
863 	if (joliet_level && opt.utf8 == 0) {
864 		char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
865 		sbi->s_nls_iocharset = load_nls(p);
866 		if (! sbi->s_nls_iocharset) {
867 			/* Fail only if explicit charset specified */
868 			if (opt.iocharset)
869 				goto out_freesbi;
870 			sbi->s_nls_iocharset = load_nls_default();
871 		}
872 	}
873 #endif
874 	s->s_op = &isofs_sops;
875 	s->s_export_op = &isofs_export_ops;
876 	sbi->s_mapping = opt.map;
877 	sbi->s_rock = (opt.rock ? 2 : 0);
878 	sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
879 	sbi->s_cruft = opt.cruft;
880 	sbi->s_hide = opt.hide;
881 	sbi->s_showassoc = opt.showassoc;
882 	sbi->s_uid = opt.uid;
883 	sbi->s_gid = opt.gid;
884 	sbi->s_uid_set = opt.uid_set;
885 	sbi->s_gid_set = opt.gid_set;
886 	sbi->s_utf8 = opt.utf8;
887 	sbi->s_nocompress = opt.nocompress;
888 	sbi->s_overriderockperm = opt.overriderockperm;
889 	/*
890 	 * It would be incredibly stupid to allow people to mark every file
891 	 * on the disk as suid, so we merely allow them to set the default
892 	 * permissions.
893 	 */
894 	if (opt.fmode != ISOFS_INVALID_MODE)
895 		sbi->s_fmode = opt.fmode & 0777;
896 	else
897 		sbi->s_fmode = ISOFS_INVALID_MODE;
898 	if (opt.dmode != ISOFS_INVALID_MODE)
899 		sbi->s_dmode = opt.dmode & 0777;
900 	else
901 		sbi->s_dmode = ISOFS_INVALID_MODE;
902 
903 	/*
904 	 * Read the root inode, which _may_ result in changing
905 	 * the s_rock flag. Once we have the final s_rock value,
906 	 * we then decide whether to use the Joliet descriptor.
907 	 */
908 	inode = isofs_iget(s, sbi->s_firstdatazone, 0);
909 	if (IS_ERR(inode))
910 		goto out_no_root;
911 
912 	/*
913 	 * Fix for broken CDs with Rock Ridge and empty ISO root directory but
914 	 * correct Joliet root directory.
915 	 */
916 	if (sbi->s_rock == 1 && joliet_level &&
917 				rootdir_empty(s, sbi->s_firstdatazone)) {
918 		printk(KERN_NOTICE
919 			"ISOFS: primary root directory is empty. "
920 			"Disabling Rock Ridge and switching to Joliet.");
921 		sbi->s_rock = 0;
922 	}
923 
924 	/*
925 	 * If this disk has both Rock Ridge and Joliet on it, then we
926 	 * want to use Rock Ridge by default.  This can be overridden
927 	 * by using the norock mount option.  There is still one other
928 	 * possibility that is not taken into account: a Rock Ridge
929 	 * CD with Unicode names.  Until someone sees such a beast, it
930 	 * will not be supported.
931 	 */
932 	if (sbi->s_rock == 1) {
933 		joliet_level = 0;
934 	} else if (joliet_level) {
935 		sbi->s_rock = 0;
936 		if (sbi->s_firstdatazone != first_data_zone) {
937 			sbi->s_firstdatazone = first_data_zone;
938 			printk(KERN_DEBUG
939 				"ISOFS: changing to secondary root\n");
940 			iput(inode);
941 			inode = isofs_iget(s, sbi->s_firstdatazone, 0);
942 			if (IS_ERR(inode))
943 				goto out_no_root;
944 		}
945 	}
946 
947 	if (opt.check == 'u') {
948 		/* Only Joliet is case insensitive by default */
949 		if (joliet_level)
950 			opt.check = 'r';
951 		else
952 			opt.check = 's';
953 	}
954 	sbi->s_joliet_level = joliet_level;
955 
956 	/* Make sure the root inode is a directory */
957 	if (!S_ISDIR(inode->i_mode)) {
958 		printk(KERN_WARNING
959 			"isofs_fill_super: root inode is not a directory. "
960 			"Corrupted media?\n");
961 		goto out_iput;
962 	}
963 
964 	table = 0;
965 	if (joliet_level)
966 		table += 2;
967 	if (opt.check == 'r')
968 		table++;
969 	sbi->s_check = opt.check;
970 
971 	if (table)
972 		s->s_d_op = &isofs_dentry_ops[table - 1];
973 
974 	/* get the root dentry */
975 	s->s_root = d_make_root(inode);
976 	if (!(s->s_root)) {
977 		error = -ENOMEM;
978 		goto out_no_inode;
979 	}
980 
981 	kfree(opt.iocharset);
982 
983 	return 0;
984 
985 	/*
986 	 * Display error messages and free resources.
987 	 */
988 out_iput:
989 	iput(inode);
990 	goto out_no_inode;
991 out_no_root:
992 	error = PTR_ERR(inode);
993 	if (error != -ENOMEM)
994 		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
995 out_no_inode:
996 #ifdef CONFIG_JOLIET
997 	unload_nls(sbi->s_nls_iocharset);
998 #endif
999 	goto out_freesbi;
1000 out_no_read:
1001 	printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
1002 		__func__, s->s_id, iso_blknum, block);
1003 	goto out_freebh;
1004 out_bad_zone_size:
1005 	printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
1006 		sbi->s_log_zone_size);
1007 	goto out_freebh;
1008 out_bad_size:
1009 	printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
1010 		orig_zonesize, opt.blocksize);
1011 	goto out_freebh;
1012 out_unknown_format:
1013 	if (!silent)
1014 		printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
1015 
1016 out_freebh:
1017 	brelse(bh);
1018 	brelse(pri_bh);
1019 out_freesbi:
1020 	kfree(opt.iocharset);
1021 	kfree(sbi);
1022 	s->s_fs_info = NULL;
1023 	return error;
1024 }
1025 
1026 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
1027 {
1028 	struct super_block *sb = dentry->d_sb;
1029 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1030 
1031 	buf->f_type = ISOFS_SUPER_MAGIC;
1032 	buf->f_bsize = sb->s_blocksize;
1033 	buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1034 		<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1035 	buf->f_bfree = 0;
1036 	buf->f_bavail = 0;
1037 	buf->f_files = ISOFS_SB(sb)->s_ninodes;
1038 	buf->f_ffree = 0;
1039 	buf->f_fsid.val[0] = (u32)id;
1040 	buf->f_fsid.val[1] = (u32)(id >> 32);
1041 	buf->f_namelen = NAME_MAX;
1042 	return 0;
1043 }
1044 
1045 /*
1046  * Get a set of blocks; filling in buffer_heads if already allocated
1047  * or getblk() if they are not.  Returns the number of blocks inserted
1048  * (-ve == error.)
1049  */
1050 int isofs_get_blocks(struct inode *inode, sector_t iblock,
1051 		     struct buffer_head **bh, unsigned long nblocks)
1052 {
1053 	unsigned long b_off = iblock;
1054 	unsigned offset, sect_size;
1055 	unsigned int firstext;
1056 	unsigned long nextblk, nextoff;
1057 	int section, rv, error;
1058 	struct iso_inode_info *ei = ISOFS_I(inode);
1059 
1060 	error = -EIO;
1061 	rv = 0;
1062 	if (iblock != b_off) {
1063 		printk(KERN_DEBUG "%s: block number too large\n", __func__);
1064 		goto abort;
1065 	}
1066 
1067 
1068 	offset = 0;
1069 	firstext = ei->i_first_extent;
1070 	sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1071 	nextblk = ei->i_next_section_block;
1072 	nextoff = ei->i_next_section_offset;
1073 	section = 0;
1074 
1075 	while (nblocks) {
1076 		/* If we are *way* beyond the end of the file, print a message.
1077 		 * Access beyond the end of the file up to the next page boundary
1078 		 * is normal, however because of the way the page cache works.
1079 		 * In this case, we just return 0 so that we can properly fill
1080 		 * the page with useless information without generating any
1081 		 * I/O errors.
1082 		 */
1083 		if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1084 			printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1085 				__func__, b_off,
1086 				(unsigned long long)inode->i_size);
1087 			goto abort;
1088 		}
1089 
1090 		/* On the last section, nextblk == 0, section size is likely to
1091 		 * exceed sect_size by a partial block, and access beyond the
1092 		 * end of the file will reach beyond the section size, too.
1093 		 */
1094 		while (nextblk && (b_off >= (offset + sect_size))) {
1095 			struct inode *ninode;
1096 
1097 			offset += sect_size;
1098 			ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1099 			if (IS_ERR(ninode)) {
1100 				error = PTR_ERR(ninode);
1101 				goto abort;
1102 			}
1103 			firstext  = ISOFS_I(ninode)->i_first_extent;
1104 			sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1105 			nextblk   = ISOFS_I(ninode)->i_next_section_block;
1106 			nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1107 			iput(ninode);
1108 
1109 			if (++section > 100) {
1110 				printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1111 					" aborting...\n", __func__);
1112 				printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1113 					"nextblk=%lu nextoff=%lu\n", __func__,
1114 					b_off, firstext, (unsigned) sect_size,
1115 					nextblk, nextoff);
1116 				goto abort;
1117 			}
1118 		}
1119 
1120 		if (*bh) {
1121 			map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1122 		} else {
1123 			*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1124 			if (!*bh)
1125 				goto abort;
1126 		}
1127 		bh++;	/* Next buffer head */
1128 		b_off++;	/* Next buffer offset */
1129 		nblocks--;
1130 		rv++;
1131 	}
1132 
1133 	error = 0;
1134 abort:
1135 	return rv != 0 ? rv : error;
1136 }
1137 
1138 /*
1139  * Used by the standard interfaces.
1140  */
1141 static int isofs_get_block(struct inode *inode, sector_t iblock,
1142 		    struct buffer_head *bh_result, int create)
1143 {
1144 	int ret;
1145 
1146 	if (create) {
1147 		printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1148 		return -EROFS;
1149 	}
1150 
1151 	ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1152 	return ret < 0 ? ret : 0;
1153 }
1154 
1155 static int isofs_bmap(struct inode *inode, sector_t block)
1156 {
1157 	struct buffer_head dummy;
1158 	int error;
1159 
1160 	dummy.b_state = 0;
1161 	dummy.b_blocknr = -1000;
1162 	error = isofs_get_block(inode, block, &dummy, 0);
1163 	if (!error)
1164 		return dummy.b_blocknr;
1165 	return 0;
1166 }
1167 
1168 struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1169 {
1170 	sector_t blknr = isofs_bmap(inode, block);
1171 	if (!blknr)
1172 		return NULL;
1173 	return sb_bread(inode->i_sb, blknr);
1174 }
1175 
1176 static int isofs_readpage(struct file *file, struct page *page)
1177 {
1178 	return mpage_readpage(page, isofs_get_block);
1179 }
1180 
1181 static int isofs_readpages(struct file *file, struct address_space *mapping,
1182 			struct list_head *pages, unsigned nr_pages)
1183 {
1184 	return mpage_readpages(mapping, pages, nr_pages, isofs_get_block);
1185 }
1186 
1187 static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1188 {
1189 	return generic_block_bmap(mapping,block,isofs_get_block);
1190 }
1191 
1192 static const struct address_space_operations isofs_aops = {
1193 	.readpage = isofs_readpage,
1194 	.readpages = isofs_readpages,
1195 	.bmap = _isofs_bmap
1196 };
1197 
1198 static int isofs_read_level3_size(struct inode *inode)
1199 {
1200 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1201 	int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1202 	struct buffer_head *bh = NULL;
1203 	unsigned long block, offset, block_saved, offset_saved;
1204 	int i = 0;
1205 	int more_entries = 0;
1206 	struct iso_directory_record *tmpde = NULL;
1207 	struct iso_inode_info *ei = ISOFS_I(inode);
1208 
1209 	inode->i_size = 0;
1210 
1211 	/* The first 16 blocks are reserved as the System Area.  Thus,
1212 	 * no inodes can appear in block 0.  We use this to flag that
1213 	 * this is the last section. */
1214 	ei->i_next_section_block = 0;
1215 	ei->i_next_section_offset = 0;
1216 
1217 	block = ei->i_iget5_block;
1218 	offset = ei->i_iget5_offset;
1219 
1220 	do {
1221 		struct iso_directory_record *de;
1222 		unsigned int de_len;
1223 
1224 		if (!bh) {
1225 			bh = sb_bread(inode->i_sb, block);
1226 			if (!bh)
1227 				goto out_noread;
1228 		}
1229 		de = (struct iso_directory_record *) (bh->b_data + offset);
1230 		de_len = *(unsigned char *) de;
1231 
1232 		if (de_len == 0) {
1233 			brelse(bh);
1234 			bh = NULL;
1235 			++block;
1236 			offset = 0;
1237 			continue;
1238 		}
1239 
1240 		block_saved = block;
1241 		offset_saved = offset;
1242 		offset += de_len;
1243 
1244 		/* Make sure we have a full directory entry */
1245 		if (offset >= bufsize) {
1246 			int slop = bufsize - offset + de_len;
1247 			if (!tmpde) {
1248 				tmpde = kmalloc(256, GFP_KERNEL);
1249 				if (!tmpde)
1250 					goto out_nomem;
1251 			}
1252 			memcpy(tmpde, de, slop);
1253 			offset &= bufsize - 1;
1254 			block++;
1255 			brelse(bh);
1256 			bh = NULL;
1257 			if (offset) {
1258 				bh = sb_bread(inode->i_sb, block);
1259 				if (!bh)
1260 					goto out_noread;
1261 				memcpy((void *)tmpde+slop, bh->b_data, offset);
1262 			}
1263 			de = tmpde;
1264 		}
1265 
1266 		inode->i_size += isonum_733(de->size);
1267 		if (i == 1) {
1268 			ei->i_next_section_block = block_saved;
1269 			ei->i_next_section_offset = offset_saved;
1270 		}
1271 
1272 		more_entries = de->flags[-high_sierra] & 0x80;
1273 
1274 		i++;
1275 		if (i > 100)
1276 			goto out_toomany;
1277 	} while (more_entries);
1278 out:
1279 	kfree(tmpde);
1280 	if (bh)
1281 		brelse(bh);
1282 	return 0;
1283 
1284 out_nomem:
1285 	if (bh)
1286 		brelse(bh);
1287 	return -ENOMEM;
1288 
1289 out_noread:
1290 	printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1291 	kfree(tmpde);
1292 	return -EIO;
1293 
1294 out_toomany:
1295 	printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1296 		"isofs_read_level3_size: inode=%lu\n",
1297 		__func__, inode->i_ino);
1298 	goto out;
1299 }
1300 
1301 static int isofs_read_inode(struct inode *inode, int relocated)
1302 {
1303 	struct super_block *sb = inode->i_sb;
1304 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
1305 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1306 	unsigned long block;
1307 	int high_sierra = sbi->s_high_sierra;
1308 	struct buffer_head *bh;
1309 	struct iso_directory_record *de;
1310 	struct iso_directory_record *tmpde = NULL;
1311 	unsigned int de_len;
1312 	unsigned long offset;
1313 	struct iso_inode_info *ei = ISOFS_I(inode);
1314 	int ret = -EIO;
1315 
1316 	block = ei->i_iget5_block;
1317 	bh = sb_bread(inode->i_sb, block);
1318 	if (!bh)
1319 		goto out_badread;
1320 
1321 	offset = ei->i_iget5_offset;
1322 
1323 	de = (struct iso_directory_record *) (bh->b_data + offset);
1324 	de_len = *(unsigned char *) de;
1325 
1326 	if (offset + de_len > bufsize) {
1327 		int frag1 = bufsize - offset;
1328 
1329 		tmpde = kmalloc(de_len, GFP_KERNEL);
1330 		if (!tmpde) {
1331 			ret = -ENOMEM;
1332 			goto fail;
1333 		}
1334 		memcpy(tmpde, bh->b_data + offset, frag1);
1335 		brelse(bh);
1336 		bh = sb_bread(inode->i_sb, ++block);
1337 		if (!bh)
1338 			goto out_badread;
1339 		memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1340 		de = tmpde;
1341 	}
1342 
1343 	inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1344 					ei->i_iget5_offset,
1345 					ISOFS_BUFFER_BITS(inode));
1346 
1347 	/* Assume it is a normal-format file unless told otherwise */
1348 	ei->i_file_format = isofs_file_normal;
1349 
1350 	if (de->flags[-high_sierra] & 2) {
1351 		if (sbi->s_dmode != ISOFS_INVALID_MODE)
1352 			inode->i_mode = S_IFDIR | sbi->s_dmode;
1353 		else
1354 			inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1355 		set_nlink(inode, 1);	/*
1356 					 * Set to 1.  We know there are 2, but
1357 					 * the find utility tries to optimize
1358 					 * if it is 2, and it screws up.  It is
1359 					 * easier to give 1 which tells find to
1360 					 * do it the hard way.
1361 					 */
1362 	} else {
1363 		if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1364 			inode->i_mode = S_IFREG | sbi->s_fmode;
1365 		} else {
1366 			/*
1367 			 * Set default permissions: r-x for all.  The disc
1368 			 * could be shared with DOS machines so virtually
1369 			 * anything could be a valid executable.
1370 			 */
1371 			inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1372 		}
1373 		set_nlink(inode, 1);
1374 	}
1375 	inode->i_uid = sbi->s_uid;
1376 	inode->i_gid = sbi->s_gid;
1377 	inode->i_blocks = 0;
1378 
1379 	ei->i_format_parm[0] = 0;
1380 	ei->i_format_parm[1] = 0;
1381 	ei->i_format_parm[2] = 0;
1382 
1383 	ei->i_section_size = isonum_733(de->size);
1384 	if (de->flags[-high_sierra] & 0x80) {
1385 		ret = isofs_read_level3_size(inode);
1386 		if (ret < 0)
1387 			goto fail;
1388 		ret = -EIO;
1389 	} else {
1390 		ei->i_next_section_block = 0;
1391 		ei->i_next_section_offset = 0;
1392 		inode->i_size = isonum_733(de->size);
1393 	}
1394 
1395 	/*
1396 	 * Some dipshit decided to store some other bit of information
1397 	 * in the high byte of the file length.  Truncate size in case
1398 	 * this CDROM was mounted with the cruft option.
1399 	 */
1400 
1401 	if (sbi->s_cruft)
1402 		inode->i_size &= 0x00ffffff;
1403 
1404 	if (de->interleave[0]) {
1405 		printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1406 		inode->i_size = 0;
1407 	}
1408 
1409 	/* I have no idea what file_unit_size is used for, so
1410 	   we will flag it for now */
1411 	if (de->file_unit_size[0] != 0) {
1412 		printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1413 			inode->i_ino);
1414 	}
1415 
1416 	/* I have no idea what other flag bits are used for, so
1417 	   we will flag it for now */
1418 #ifdef DEBUG
1419 	if((de->flags[-high_sierra] & ~2)!= 0){
1420 		printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1421 				"(%ld %x).\n",
1422 			inode->i_ino, de->flags[-high_sierra]);
1423 	}
1424 #endif
1425 
1426 	inode->i_mtime.tv_sec =
1427 	inode->i_atime.tv_sec =
1428 	inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
1429 	inode->i_mtime.tv_nsec =
1430 	inode->i_atime.tv_nsec =
1431 	inode->i_ctime.tv_nsec = 0;
1432 
1433 	ei->i_first_extent = (isonum_733(de->extent) +
1434 			isonum_711(de->ext_attr_length));
1435 
1436 	/* Set the number of blocks for stat() - should be done before RR */
1437 	inode->i_blocks = (inode->i_size + 511) >> 9;
1438 
1439 	/*
1440 	 * Now test for possible Rock Ridge extensions which will override
1441 	 * some of these numbers in the inode structure.
1442 	 */
1443 
1444 	if (!high_sierra) {
1445 		parse_rock_ridge_inode(de, inode, relocated);
1446 		/* if we want uid/gid set, override the rock ridge setting */
1447 		if (sbi->s_uid_set)
1448 			inode->i_uid = sbi->s_uid;
1449 		if (sbi->s_gid_set)
1450 			inode->i_gid = sbi->s_gid;
1451 	}
1452 	/* Now set final access rights if overriding rock ridge setting */
1453 	if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1454 	    sbi->s_dmode != ISOFS_INVALID_MODE)
1455 		inode->i_mode = S_IFDIR | sbi->s_dmode;
1456 	if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1457 	    sbi->s_fmode != ISOFS_INVALID_MODE)
1458 		inode->i_mode = S_IFREG | sbi->s_fmode;
1459 
1460 	/* Install the inode operations vector */
1461 	if (S_ISREG(inode->i_mode)) {
1462 		inode->i_fop = &generic_ro_fops;
1463 		switch (ei->i_file_format) {
1464 #ifdef CONFIG_ZISOFS
1465 		case isofs_file_compressed:
1466 			inode->i_data.a_ops = &zisofs_aops;
1467 			break;
1468 #endif
1469 		default:
1470 			inode->i_data.a_ops = &isofs_aops;
1471 			break;
1472 		}
1473 	} else if (S_ISDIR(inode->i_mode)) {
1474 		inode->i_op = &isofs_dir_inode_operations;
1475 		inode->i_fop = &isofs_dir_operations;
1476 	} else if (S_ISLNK(inode->i_mode)) {
1477 		inode->i_op = &page_symlink_inode_operations;
1478 		inode_nohighmem(inode);
1479 		inode->i_data.a_ops = &isofs_symlink_aops;
1480 	} else
1481 		/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1482 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1483 
1484 	ret = 0;
1485 out:
1486 	kfree(tmpde);
1487 	if (bh)
1488 		brelse(bh);
1489 	return ret;
1490 
1491 out_badread:
1492 	printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1493 fail:
1494 	goto out;
1495 }
1496 
1497 struct isofs_iget5_callback_data {
1498 	unsigned long block;
1499 	unsigned long offset;
1500 };
1501 
1502 static int isofs_iget5_test(struct inode *ino, void *data)
1503 {
1504 	struct iso_inode_info *i = ISOFS_I(ino);
1505 	struct isofs_iget5_callback_data *d =
1506 		(struct isofs_iget5_callback_data*)data;
1507 	return (i->i_iget5_block == d->block)
1508 		&& (i->i_iget5_offset == d->offset);
1509 }
1510 
1511 static int isofs_iget5_set(struct inode *ino, void *data)
1512 {
1513 	struct iso_inode_info *i = ISOFS_I(ino);
1514 	struct isofs_iget5_callback_data *d =
1515 		(struct isofs_iget5_callback_data*)data;
1516 	i->i_iget5_block = d->block;
1517 	i->i_iget5_offset = d->offset;
1518 	return 0;
1519 }
1520 
1521 /* Store, in the inode's containing structure, the block and block
1522  * offset that point to the underlying meta-data for the inode.  The
1523  * code below is otherwise similar to the iget() code in
1524  * include/linux/fs.h */
1525 struct inode *__isofs_iget(struct super_block *sb,
1526 			   unsigned long block,
1527 			   unsigned long offset,
1528 			   int relocated)
1529 {
1530 	unsigned long hashval;
1531 	struct inode *inode;
1532 	struct isofs_iget5_callback_data data;
1533 	long ret;
1534 
1535 	if (offset >= 1ul << sb->s_blocksize_bits)
1536 		return ERR_PTR(-EINVAL);
1537 
1538 	data.block = block;
1539 	data.offset = offset;
1540 
1541 	hashval = (block << sb->s_blocksize_bits) | offset;
1542 
1543 	inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1544 				&isofs_iget5_set, &data);
1545 
1546 	if (!inode)
1547 		return ERR_PTR(-ENOMEM);
1548 
1549 	if (inode->i_state & I_NEW) {
1550 		ret = isofs_read_inode(inode, relocated);
1551 		if (ret < 0) {
1552 			iget_failed(inode);
1553 			inode = ERR_PTR(ret);
1554 		} else {
1555 			unlock_new_inode(inode);
1556 		}
1557 	}
1558 
1559 	return inode;
1560 }
1561 
1562 static struct dentry *isofs_mount(struct file_system_type *fs_type,
1563 	int flags, const char *dev_name, void *data)
1564 {
1565 	return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1566 }
1567 
1568 static struct file_system_type iso9660_fs_type = {
1569 	.owner		= THIS_MODULE,
1570 	.name		= "iso9660",
1571 	.mount		= isofs_mount,
1572 	.kill_sb	= kill_block_super,
1573 	.fs_flags	= FS_REQUIRES_DEV,
1574 };
1575 MODULE_ALIAS_FS("iso9660");
1576 MODULE_ALIAS("iso9660");
1577 
1578 static int __init init_iso9660_fs(void)
1579 {
1580 	int err = init_inodecache();
1581 	if (err)
1582 		goto out;
1583 #ifdef CONFIG_ZISOFS
1584 	err = zisofs_init();
1585 	if (err)
1586 		goto out1;
1587 #endif
1588 	err = register_filesystem(&iso9660_fs_type);
1589 	if (err)
1590 		goto out2;
1591 	return 0;
1592 out2:
1593 #ifdef CONFIG_ZISOFS
1594 	zisofs_cleanup();
1595 out1:
1596 #endif
1597 	destroy_inodecache();
1598 out:
1599 	return err;
1600 }
1601 
1602 static void __exit exit_iso9660_fs(void)
1603 {
1604         unregister_filesystem(&iso9660_fs_type);
1605 #ifdef CONFIG_ZISOFS
1606 	zisofs_cleanup();
1607 #endif
1608 	destroy_inodecache();
1609 }
1610 
1611 module_init(init_iso9660_fs)
1612 module_exit(exit_iso9660_fs)
1613 MODULE_LICENSE("GPL");
1614