xref: /openbmc/linux/fs/isofs/inode.c (revision cfbb9be8)
1 /*
2  *  linux/fs/isofs/inode.c
3  *
4  *  (C) 1991  Linus Torvalds - minix filesystem
5  *      1992, 1993, 1994  Eric Youngdale Modified for ISO 9660 filesystem.
6  *      1994  Eberhard Mönkeberg - multi session handling.
7  *      1995  Mark Dobie - allow mounting of some weird VideoCDs and PhotoCDs.
8  *	1997  Gordon Chaffee - Joliet CDs
9  *	1998  Eric Lammerts - ISO 9660 Level 3
10  *	2004  Paul Serice - Inode Support pushed out from 4GB to 128GB
11  *	2004  Paul Serice - NFS Export Operations
12  */
13 
14 #include <linux/init.h>
15 #include <linux/module.h>
16 
17 #include <linux/slab.h>
18 #include <linux/cred.h>
19 #include <linux/nls.h>
20 #include <linux/ctype.h>
21 #include <linux/statfs.h>
22 #include <linux/cdrom.h>
23 #include <linux/parser.h>
24 #include <linux/mpage.h>
25 #include <linux/user_namespace.h>
26 #include <linux/seq_file.h>
27 
28 #include "isofs.h"
29 #include "zisofs.h"
30 
31 #define BEQUIET
32 
33 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
34 static int isofs_dentry_cmpi(const struct dentry *dentry,
35 		unsigned int len, const char *str, const struct qstr *name);
36 
37 #ifdef CONFIG_JOLIET
38 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
39 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
40 static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
41 		unsigned int len, const char *str, const struct qstr *name);
42 static int isofs_dentry_cmp_ms(const struct dentry *dentry,
43 		unsigned int len, const char *str, const struct qstr *name);
44 #endif
45 
46 static void isofs_put_super(struct super_block *sb)
47 {
48 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
49 
50 #ifdef CONFIG_JOLIET
51 	unload_nls(sbi->s_nls_iocharset);
52 #endif
53 
54 	kfree(sbi);
55 	sb->s_fs_info = NULL;
56 	return;
57 }
58 
59 static int isofs_read_inode(struct inode *, int relocated);
60 static int isofs_statfs (struct dentry *, struct kstatfs *);
61 static int isofs_show_options(struct seq_file *, struct dentry *);
62 
63 static struct kmem_cache *isofs_inode_cachep;
64 
65 static struct inode *isofs_alloc_inode(struct super_block *sb)
66 {
67 	struct iso_inode_info *ei;
68 	ei = kmem_cache_alloc(isofs_inode_cachep, GFP_KERNEL);
69 	if (!ei)
70 		return NULL;
71 	return &ei->vfs_inode;
72 }
73 
74 static void isofs_i_callback(struct rcu_head *head)
75 {
76 	struct inode *inode = container_of(head, struct inode, i_rcu);
77 	kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
78 }
79 
80 static void isofs_destroy_inode(struct inode *inode)
81 {
82 	call_rcu(&inode->i_rcu, isofs_i_callback);
83 }
84 
85 static void init_once(void *foo)
86 {
87 	struct iso_inode_info *ei = foo;
88 
89 	inode_init_once(&ei->vfs_inode);
90 }
91 
92 static int __init init_inodecache(void)
93 {
94 	isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
95 					sizeof(struct iso_inode_info),
96 					0, (SLAB_RECLAIM_ACCOUNT|
97 					SLAB_MEM_SPREAD|SLAB_ACCOUNT),
98 					init_once);
99 	if (!isofs_inode_cachep)
100 		return -ENOMEM;
101 	return 0;
102 }
103 
104 static void destroy_inodecache(void)
105 {
106 	/*
107 	 * Make sure all delayed rcu free inodes are flushed before we
108 	 * destroy cache.
109 	 */
110 	rcu_barrier();
111 	kmem_cache_destroy(isofs_inode_cachep);
112 }
113 
114 static int isofs_remount(struct super_block *sb, int *flags, char *data)
115 {
116 	sync_filesystem(sb);
117 	if (!(*flags & SB_RDONLY))
118 		return -EROFS;
119 	return 0;
120 }
121 
122 static const struct super_operations isofs_sops = {
123 	.alloc_inode	= isofs_alloc_inode,
124 	.destroy_inode	= isofs_destroy_inode,
125 	.put_super	= isofs_put_super,
126 	.statfs		= isofs_statfs,
127 	.remount_fs	= isofs_remount,
128 	.show_options	= isofs_show_options,
129 };
130 
131 
132 static const struct dentry_operations isofs_dentry_ops[] = {
133 	{
134 		.d_hash		= isofs_hashi,
135 		.d_compare	= isofs_dentry_cmpi,
136 	},
137 #ifdef CONFIG_JOLIET
138 	{
139 		.d_hash		= isofs_hash_ms,
140 		.d_compare	= isofs_dentry_cmp_ms,
141 	},
142 	{
143 		.d_hash		= isofs_hashi_ms,
144 		.d_compare	= isofs_dentry_cmpi_ms,
145 	},
146 #endif
147 };
148 
149 struct iso9660_options{
150 	unsigned int rock:1;
151 	unsigned int joliet:1;
152 	unsigned int cruft:1;
153 	unsigned int hide:1;
154 	unsigned int showassoc:1;
155 	unsigned int nocompress:1;
156 	unsigned int overriderockperm:1;
157 	unsigned int uid_set:1;
158 	unsigned int gid_set:1;
159 	unsigned int utf8:1;
160 	unsigned char map;
161 	unsigned char check;
162 	unsigned int blocksize;
163 	umode_t fmode;
164 	umode_t dmode;
165 	kgid_t gid;
166 	kuid_t uid;
167 	char *iocharset;
168 	/* LVE */
169 	s32 session;
170 	s32 sbsector;
171 };
172 
173 /*
174  * Compute the hash for the isofs name corresponding to the dentry.
175  */
176 static int
177 isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
178 {
179 	const char *name;
180 	int len;
181 	char c;
182 	unsigned long hash;
183 
184 	len = qstr->len;
185 	name = qstr->name;
186 	if (ms) {
187 		while (len && name[len-1] == '.')
188 			len--;
189 	}
190 
191 	hash = init_name_hash(dentry);
192 	while (len--) {
193 		c = tolower(*name++);
194 		hash = partial_name_hash(c, hash);
195 	}
196 	qstr->hash = end_name_hash(hash);
197 
198 	return 0;
199 }
200 
201 /*
202  * Compare of two isofs names.
203  */
204 static int isofs_dentry_cmp_common(
205 		unsigned int len, const char *str,
206 		const struct qstr *name, int ms, int ci)
207 {
208 	int alen, blen;
209 
210 	/* A filename cannot end in '.' or we treat it like it has none */
211 	alen = name->len;
212 	blen = len;
213 	if (ms) {
214 		while (alen && name->name[alen-1] == '.')
215 			alen--;
216 		while (blen && str[blen-1] == '.')
217 			blen--;
218 	}
219 	if (alen == blen) {
220 		if (ci) {
221 			if (strncasecmp(name->name, str, alen) == 0)
222 				return 0;
223 		} else {
224 			if (strncmp(name->name, str, alen) == 0)
225 				return 0;
226 		}
227 	}
228 	return 1;
229 }
230 
231 static int
232 isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
233 {
234 	return isofs_hashi_common(dentry, qstr, 0);
235 }
236 
237 static int
238 isofs_dentry_cmpi(const struct dentry *dentry,
239 		unsigned int len, const char *str, const struct qstr *name)
240 {
241 	return isofs_dentry_cmp_common(len, str, name, 0, 1);
242 }
243 
244 #ifdef CONFIG_JOLIET
245 /*
246  * Compute the hash for the isofs name corresponding to the dentry.
247  */
248 static int
249 isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
250 {
251 	const char *name;
252 	int len;
253 
254 	len = qstr->len;
255 	name = qstr->name;
256 	if (ms) {
257 		while (len && name[len-1] == '.')
258 			len--;
259 	}
260 
261 	qstr->hash = full_name_hash(dentry, name, len);
262 
263 	return 0;
264 }
265 
266 static int
267 isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
268 {
269 	return isofs_hash_common(dentry, qstr, 1);
270 }
271 
272 static int
273 isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
274 {
275 	return isofs_hashi_common(dentry, qstr, 1);
276 }
277 
278 static int
279 isofs_dentry_cmp_ms(const struct dentry *dentry,
280 		unsigned int len, const char *str, const struct qstr *name)
281 {
282 	return isofs_dentry_cmp_common(len, str, name, 1, 0);
283 }
284 
285 static int
286 isofs_dentry_cmpi_ms(const struct dentry *dentry,
287 		unsigned int len, const char *str, const struct qstr *name)
288 {
289 	return isofs_dentry_cmp_common(len, str, name, 1, 1);
290 }
291 #endif
292 
293 enum {
294 	Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
295 	Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
296 	Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
297 	Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
298 };
299 
300 static const match_table_t tokens = {
301 	{Opt_norock, "norock"},
302 	{Opt_nojoliet, "nojoliet"},
303 	{Opt_unhide, "unhide"},
304 	{Opt_hide, "hide"},
305 	{Opt_showassoc, "showassoc"},
306 	{Opt_cruft, "cruft"},
307 	{Opt_utf8, "utf8"},
308 	{Opt_iocharset, "iocharset=%s"},
309 	{Opt_map_a, "map=acorn"},
310 	{Opt_map_a, "map=a"},
311 	{Opt_map_n, "map=normal"},
312 	{Opt_map_n, "map=n"},
313 	{Opt_map_o, "map=off"},
314 	{Opt_map_o, "map=o"},
315 	{Opt_session, "session=%u"},
316 	{Opt_sb, "sbsector=%u"},
317 	{Opt_check_r, "check=relaxed"},
318 	{Opt_check_r, "check=r"},
319 	{Opt_check_s, "check=strict"},
320 	{Opt_check_s, "check=s"},
321 	{Opt_uid, "uid=%u"},
322 	{Opt_gid, "gid=%u"},
323 	{Opt_mode, "mode=%u"},
324 	{Opt_dmode, "dmode=%u"},
325 	{Opt_overriderockperm, "overriderockperm"},
326 	{Opt_block, "block=%u"},
327 	{Opt_ignore, "conv=binary"},
328 	{Opt_ignore, "conv=b"},
329 	{Opt_ignore, "conv=text"},
330 	{Opt_ignore, "conv=t"},
331 	{Opt_ignore, "conv=mtext"},
332 	{Opt_ignore, "conv=m"},
333 	{Opt_ignore, "conv=auto"},
334 	{Opt_ignore, "conv=a"},
335 	{Opt_nocompress, "nocompress"},
336 	{Opt_err, NULL}
337 };
338 
339 static int parse_options(char *options, struct iso9660_options *popt)
340 {
341 	char *p;
342 	int option;
343 
344 	popt->map = 'n';
345 	popt->rock = 1;
346 	popt->joliet = 1;
347 	popt->cruft = 0;
348 	popt->hide = 0;
349 	popt->showassoc = 0;
350 	popt->check = 'u';		/* unset */
351 	popt->nocompress = 0;
352 	popt->blocksize = 1024;
353 	popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
354 	popt->uid_set = 0;
355 	popt->gid_set = 0;
356 	popt->gid = GLOBAL_ROOT_GID;
357 	popt->uid = GLOBAL_ROOT_UID;
358 	popt->iocharset = NULL;
359 	popt->utf8 = 0;
360 	popt->overriderockperm = 0;
361 	popt->session=-1;
362 	popt->sbsector=-1;
363 	if (!options)
364 		return 1;
365 
366 	while ((p = strsep(&options, ",")) != NULL) {
367 		int token;
368 		substring_t args[MAX_OPT_ARGS];
369 		unsigned n;
370 
371 		if (!*p)
372 			continue;
373 
374 		token = match_token(p, tokens, args);
375 		switch (token) {
376 		case Opt_norock:
377 			popt->rock = 0;
378 			break;
379 		case Opt_nojoliet:
380 			popt->joliet = 0;
381 			break;
382 		case Opt_hide:
383 			popt->hide = 1;
384 			break;
385 		case Opt_unhide:
386 		case Opt_showassoc:
387 			popt->showassoc = 1;
388 			break;
389 		case Opt_cruft:
390 			popt->cruft = 1;
391 			break;
392 		case Opt_utf8:
393 			popt->utf8 = 1;
394 			break;
395 #ifdef CONFIG_JOLIET
396 		case Opt_iocharset:
397 			popt->iocharset = match_strdup(&args[0]);
398 			break;
399 #endif
400 		case Opt_map_a:
401 			popt->map = 'a';
402 			break;
403 		case Opt_map_o:
404 			popt->map = 'o';
405 			break;
406 		case Opt_map_n:
407 			popt->map = 'n';
408 			break;
409 		case Opt_session:
410 			if (match_int(&args[0], &option))
411 				return 0;
412 			n = option;
413 			/*
414 			 * Track numbers are supposed to be in range 1-99, the
415 			 * mount option starts indexing at 0.
416 			 */
417 			if (n >= 99)
418 				return 0;
419 			popt->session = n + 1;
420 			break;
421 		case Opt_sb:
422 			if (match_int(&args[0], &option))
423 				return 0;
424 			popt->sbsector = option;
425 			break;
426 		case Opt_check_r:
427 			popt->check = 'r';
428 			break;
429 		case Opt_check_s:
430 			popt->check = 's';
431 			break;
432 		case Opt_ignore:
433 			break;
434 		case Opt_uid:
435 			if (match_int(&args[0], &option))
436 				return 0;
437 			popt->uid = make_kuid(current_user_ns(), option);
438 			if (!uid_valid(popt->uid))
439 				return 0;
440 			popt->uid_set = 1;
441 			break;
442 		case Opt_gid:
443 			if (match_int(&args[0], &option))
444 				return 0;
445 			popt->gid = make_kgid(current_user_ns(), option);
446 			if (!gid_valid(popt->gid))
447 				return 0;
448 			popt->gid_set = 1;
449 			break;
450 		case Opt_mode:
451 			if (match_int(&args[0], &option))
452 				return 0;
453 			popt->fmode = option;
454 			break;
455 		case Opt_dmode:
456 			if (match_int(&args[0], &option))
457 				return 0;
458 			popt->dmode = option;
459 			break;
460 		case Opt_overriderockperm:
461 			popt->overriderockperm = 1;
462 			break;
463 		case Opt_block:
464 			if (match_int(&args[0], &option))
465 				return 0;
466 			n = option;
467 			if (n != 512 && n != 1024 && n != 2048)
468 				return 0;
469 			popt->blocksize = n;
470 			break;
471 		case Opt_nocompress:
472 			popt->nocompress = 1;
473 			break;
474 		default:
475 			return 0;
476 		}
477 	}
478 	return 1;
479 }
480 
481 /*
482  * Display the mount options in /proc/mounts.
483  */
484 static int isofs_show_options(struct seq_file *m, struct dentry *root)
485 {
486 	struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
487 
488 	if (!sbi->s_rock)		seq_puts(m, ",norock");
489 	else if (!sbi->s_joliet_level)	seq_puts(m, ",nojoliet");
490 	if (sbi->s_cruft)		seq_puts(m, ",cruft");
491 	if (sbi->s_hide)		seq_puts(m, ",hide");
492 	if (sbi->s_nocompress)		seq_puts(m, ",nocompress");
493 	if (sbi->s_overriderockperm)	seq_puts(m, ",overriderockperm");
494 	if (sbi->s_showassoc)		seq_puts(m, ",showassoc");
495 	if (sbi->s_utf8)		seq_puts(m, ",utf8");
496 
497 	if (sbi->s_check)		seq_printf(m, ",check=%c", sbi->s_check);
498 	if (sbi->s_mapping)		seq_printf(m, ",map=%c", sbi->s_mapping);
499 	if (sbi->s_session != 255)	seq_printf(m, ",session=%u", sbi->s_session - 1);
500 	if (sbi->s_sbsector != -1)	seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
501 
502 	if (root->d_sb->s_blocksize != 1024)
503 		seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
504 
505 	if (sbi->s_uid_set)
506 		seq_printf(m, ",uid=%u",
507 			   from_kuid_munged(&init_user_ns, sbi->s_uid));
508 	if (sbi->s_gid_set)
509 		seq_printf(m, ",gid=%u",
510 			   from_kgid_munged(&init_user_ns, sbi->s_gid));
511 
512 	if (sbi->s_dmode != ISOFS_INVALID_MODE)
513 		seq_printf(m, ",dmode=%o", sbi->s_dmode);
514 	if (sbi->s_fmode != ISOFS_INVALID_MODE)
515 		seq_printf(m, ",fmode=%o", sbi->s_fmode);
516 
517 #ifdef CONFIG_JOLIET
518 	if (sbi->s_nls_iocharset &&
519 	    strcmp(sbi->s_nls_iocharset->charset, CONFIG_NLS_DEFAULT) != 0)
520 		seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
521 #endif
522 	return 0;
523 }
524 
525 /*
526  * look if the driver can tell the multi session redirection value
527  *
528  * don't change this if you don't know what you do, please!
529  * Multisession is legal only with XA disks.
530  * A non-XA disk with more than one volume descriptor may do it right, but
531  * usually is written in a nowhere standardized "multi-partition" manner.
532  * Multisession uses absolute addressing (solely the first frame of the whole
533  * track is #0), multi-partition uses relative addressing (each first frame of
534  * each track is #0), and a track is not a session.
535  *
536  * A broken CDwriter software or drive firmware does not set new standards,
537  * at least not if conflicting with the existing ones.
538  *
539  * emoenke@gwdg.de
540  */
541 #define WE_OBEY_THE_WRITTEN_STANDARDS 1
542 
543 static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
544 {
545 	struct cdrom_multisession ms_info;
546 	unsigned int vol_desc_start;
547 	struct block_device *bdev = sb->s_bdev;
548 	int i;
549 
550 	vol_desc_start=0;
551 	ms_info.addr_format=CDROM_LBA;
552 	if (session > 0) {
553 		struct cdrom_tocentry Te;
554 		Te.cdte_track=session;
555 		Te.cdte_format=CDROM_LBA;
556 		i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
557 		if (!i) {
558 			printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
559 				session, Te.cdte_addr.lba,
560 				Te.cdte_ctrl&CDROM_DATA_TRACK);
561 			if ((Te.cdte_ctrl&CDROM_DATA_TRACK) == 4)
562 				return Te.cdte_addr.lba;
563 		}
564 
565 		printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
566 	}
567 	i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long) &ms_info);
568 	if (session > 0)
569 		printk(KERN_ERR "ISOFS: Invalid session number\n");
570 #if 0
571 	printk(KERN_DEBUG "isofs.inode: CDROMMULTISESSION: rc=%d\n",i);
572 	if (i==0) {
573 		printk(KERN_DEBUG "isofs.inode: XA disk: %s\n",ms_info.xa_flag?"yes":"no");
574 		printk(KERN_DEBUG "isofs.inode: vol_desc_start = %d\n", ms_info.addr.lba);
575 	}
576 #endif
577 	if (i==0)
578 #if WE_OBEY_THE_WRITTEN_STANDARDS
579 		if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
580 #endif
581 			vol_desc_start=ms_info.addr.lba;
582 	return vol_desc_start;
583 }
584 
585 /*
586  * Check if root directory is empty (has less than 3 files).
587  *
588  * Used to detect broken CDs where ISO root directory is empty but Joliet root
589  * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
590  * (and Joliet used instead) or else no files would be visible.
591  */
592 static bool rootdir_empty(struct super_block *sb, unsigned long block)
593 {
594 	int offset = 0, files = 0, de_len;
595 	struct iso_directory_record *de;
596 	struct buffer_head *bh;
597 
598 	bh = sb_bread(sb, block);
599 	if (!bh)
600 		return true;
601 	while (files < 3) {
602 		de = (struct iso_directory_record *) (bh->b_data + offset);
603 		de_len = *(unsigned char *) de;
604 		if (de_len == 0)
605 			break;
606 		files++;
607 		offset += de_len;
608 	}
609 	brelse(bh);
610 	return files < 3;
611 }
612 
613 /*
614  * Initialize the superblock and read the root inode.
615  *
616  * Note: a check_disk_change() has been done immediately prior
617  * to this call, so we don't need to check again.
618  */
619 static int isofs_fill_super(struct super_block *s, void *data, int silent)
620 {
621 	struct buffer_head *bh = NULL, *pri_bh = NULL;
622 	struct hs_primary_descriptor *h_pri = NULL;
623 	struct iso_primary_descriptor *pri = NULL;
624 	struct iso_supplementary_descriptor *sec = NULL;
625 	struct iso_directory_record *rootp;
626 	struct inode *inode;
627 	struct iso9660_options opt;
628 	struct isofs_sb_info *sbi;
629 	unsigned long first_data_zone;
630 	int joliet_level = 0;
631 	int iso_blknum, block;
632 	int orig_zonesize;
633 	int table, error = -EINVAL;
634 	unsigned int vol_desc_start;
635 
636 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
637 	if (!sbi)
638 		return -ENOMEM;
639 	s->s_fs_info = sbi;
640 
641 	if (!parse_options((char *)data, &opt))
642 		goto out_freesbi;
643 
644 	/*
645 	 * First of all, get the hardware blocksize for this device.
646 	 * If we don't know what it is, or the hardware blocksize is
647 	 * larger than the blocksize the user specified, then use
648 	 * that value.
649 	 */
650 	/*
651 	 * What if bugger tells us to go beyond page size?
652 	 */
653 	opt.blocksize = sb_min_blocksize(s, opt.blocksize);
654 
655 	sbi->s_high_sierra = 0; /* default is iso9660 */
656 	sbi->s_session = opt.session;
657 	sbi->s_sbsector = opt.sbsector;
658 
659 	vol_desc_start = (opt.sbsector != -1) ?
660 		opt.sbsector : isofs_get_last_session(s,opt.session);
661 
662 	for (iso_blknum = vol_desc_start+16;
663 		iso_blknum < vol_desc_start+100; iso_blknum++) {
664 		struct hs_volume_descriptor *hdp;
665 		struct iso_volume_descriptor  *vdp;
666 
667 		block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
668 		if (!(bh = sb_bread(s, block)))
669 			goto out_no_read;
670 
671 		vdp = (struct iso_volume_descriptor *)bh->b_data;
672 		hdp = (struct hs_volume_descriptor *)bh->b_data;
673 
674 		/*
675 		 * Due to the overlapping physical location of the descriptors,
676 		 * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
677 		 * proper identification in this case, we first check for ISO.
678 		 */
679 		if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
680 			if (isonum_711(vdp->type) == ISO_VD_END)
681 				break;
682 			if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
683 				if (!pri) {
684 					pri = (struct iso_primary_descriptor *)vdp;
685 					/* Save the buffer in case we need it ... */
686 					pri_bh = bh;
687 					bh = NULL;
688 				}
689 			}
690 #ifdef CONFIG_JOLIET
691 			else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
692 				sec = (struct iso_supplementary_descriptor *)vdp;
693 				if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
694 					if (opt.joliet) {
695 						if (sec->escape[2] == 0x40)
696 							joliet_level = 1;
697 						else if (sec->escape[2] == 0x43)
698 							joliet_level = 2;
699 						else if (sec->escape[2] == 0x45)
700 							joliet_level = 3;
701 
702 						printk(KERN_DEBUG "ISO 9660 Extensions: "
703 							"Microsoft Joliet Level %d\n",
704 							joliet_level);
705 					}
706 					goto root_found;
707 				} else {
708 				/* Unknown supplementary volume descriptor */
709 				sec = NULL;
710 				}
711 			}
712 #endif
713 		} else {
714 			if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
715 				if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
716 					goto out_freebh;
717 
718 				sbi->s_high_sierra = 1;
719 				opt.rock = 0;
720 				h_pri = (struct hs_primary_descriptor *)vdp;
721 				goto root_found;
722 			}
723 		}
724 
725 		/* Just skip any volume descriptors we don't recognize */
726 
727 		brelse(bh);
728 		bh = NULL;
729 	}
730 	/*
731 	 * If we fall through, either no volume descriptor was found,
732 	 * or else we passed a primary descriptor looking for others.
733 	 */
734 	if (!pri)
735 		goto out_unknown_format;
736 	brelse(bh);
737 	bh = pri_bh;
738 	pri_bh = NULL;
739 
740 root_found:
741 	/* We don't support read-write mounts */
742 	if (!sb_rdonly(s)) {
743 		error = -EACCES;
744 		goto out_freebh;
745 	}
746 
747 	if (joliet_level && (!pri || !opt.rock)) {
748 		/* This is the case of Joliet with the norock mount flag.
749 		 * A disc with both Joliet and Rock Ridge is handled later
750 		 */
751 		pri = (struct iso_primary_descriptor *) sec;
752 	}
753 
754 	if(sbi->s_high_sierra){
755 		rootp = (struct iso_directory_record *) h_pri->root_directory_record;
756 		sbi->s_nzones = isonum_733(h_pri->volume_space_size);
757 		sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
758 		sbi->s_max_size = isonum_733(h_pri->volume_space_size);
759 	} else {
760 		if (!pri)
761 			goto out_freebh;
762 		rootp = (struct iso_directory_record *) pri->root_directory_record;
763 		sbi->s_nzones = isonum_733(pri->volume_space_size);
764 		sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
765 		sbi->s_max_size = isonum_733(pri->volume_space_size);
766 	}
767 
768 	sbi->s_ninodes = 0; /* No way to figure this out easily */
769 
770 	orig_zonesize = sbi->s_log_zone_size;
771 	/*
772 	 * If the zone size is smaller than the hardware sector size,
773 	 * this is a fatal error.  This would occur if the disc drive
774 	 * had sectors that were 2048 bytes, but the filesystem had
775 	 * blocks that were 512 bytes (which should only very rarely
776 	 * happen.)
777 	 */
778 	if (orig_zonesize < opt.blocksize)
779 		goto out_bad_size;
780 
781 	/* RDE: convert log zone size to bit shift */
782 	switch (sbi->s_log_zone_size) {
783 	case  512: sbi->s_log_zone_size =  9; break;
784 	case 1024: sbi->s_log_zone_size = 10; break;
785 	case 2048: sbi->s_log_zone_size = 11; break;
786 
787 	default:
788 		goto out_bad_zone_size;
789 	}
790 
791 	s->s_magic = ISOFS_SUPER_MAGIC;
792 
793 	/*
794 	 * With multi-extent files, file size is only limited by the maximum
795 	 * size of a file system, which is 8 TB.
796 	 */
797 	s->s_maxbytes = 0x80000000000LL;
798 
799 	/* Set this for reference. Its not currently used except on write
800 	   which we don't have .. */
801 
802 	first_data_zone = isonum_733(rootp->extent) +
803 			  isonum_711(rootp->ext_attr_length);
804 	sbi->s_firstdatazone = first_data_zone;
805 #ifndef BEQUIET
806 	printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
807 		sbi->s_max_size, 1UL << sbi->s_log_zone_size);
808 	printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
809 	if(sbi->s_high_sierra)
810 		printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
811 #endif
812 
813 	/*
814 	 * If the Joliet level is set, we _may_ decide to use the
815 	 * secondary descriptor, but can't be sure until after we
816 	 * read the root inode. But before reading the root inode
817 	 * we may need to change the device blocksize, and would
818 	 * rather release the old buffer first. So, we cache the
819 	 * first_data_zone value from the secondary descriptor.
820 	 */
821 	if (joliet_level) {
822 		pri = (struct iso_primary_descriptor *) sec;
823 		rootp = (struct iso_directory_record *)
824 			pri->root_directory_record;
825 		first_data_zone = isonum_733(rootp->extent) +
826 				isonum_711(rootp->ext_attr_length);
827 	}
828 
829 	/*
830 	 * We're all done using the volume descriptor, and may need
831 	 * to change the device blocksize, so release the buffer now.
832 	 */
833 	brelse(pri_bh);
834 	brelse(bh);
835 
836 	/*
837 	 * Force the blocksize to 512 for 512 byte sectors.  The file
838 	 * read primitives really get it wrong in a bad way if we don't
839 	 * do this.
840 	 *
841 	 * Note - we should never be setting the blocksize to something
842 	 * less than the hardware sector size for the device.  If we
843 	 * do, we would end up having to read larger buffers and split
844 	 * out portions to satisfy requests.
845 	 *
846 	 * Note2- the idea here is that we want to deal with the optimal
847 	 * zonesize in the filesystem.  If we have it set to something less,
848 	 * then we have horrible problems with trying to piece together
849 	 * bits of adjacent blocks in order to properly read directory
850 	 * entries.  By forcing the blocksize in this way, we ensure
851 	 * that we will never be required to do this.
852 	 */
853 	sb_set_blocksize(s, orig_zonesize);
854 
855 	sbi->s_nls_iocharset = NULL;
856 
857 #ifdef CONFIG_JOLIET
858 	if (joliet_level && opt.utf8 == 0) {
859 		char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
860 		sbi->s_nls_iocharset = load_nls(p);
861 		if (! sbi->s_nls_iocharset) {
862 			/* Fail only if explicit charset specified */
863 			if (opt.iocharset)
864 				goto out_freesbi;
865 			sbi->s_nls_iocharset = load_nls_default();
866 		}
867 	}
868 #endif
869 	s->s_op = &isofs_sops;
870 	s->s_export_op = &isofs_export_ops;
871 	sbi->s_mapping = opt.map;
872 	sbi->s_rock = (opt.rock ? 2 : 0);
873 	sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
874 	sbi->s_cruft = opt.cruft;
875 	sbi->s_hide = opt.hide;
876 	sbi->s_showassoc = opt.showassoc;
877 	sbi->s_uid = opt.uid;
878 	sbi->s_gid = opt.gid;
879 	sbi->s_uid_set = opt.uid_set;
880 	sbi->s_gid_set = opt.gid_set;
881 	sbi->s_utf8 = opt.utf8;
882 	sbi->s_nocompress = opt.nocompress;
883 	sbi->s_overriderockperm = opt.overriderockperm;
884 	/*
885 	 * It would be incredibly stupid to allow people to mark every file
886 	 * on the disk as suid, so we merely allow them to set the default
887 	 * permissions.
888 	 */
889 	if (opt.fmode != ISOFS_INVALID_MODE)
890 		sbi->s_fmode = opt.fmode & 0777;
891 	else
892 		sbi->s_fmode = ISOFS_INVALID_MODE;
893 	if (opt.dmode != ISOFS_INVALID_MODE)
894 		sbi->s_dmode = opt.dmode & 0777;
895 	else
896 		sbi->s_dmode = ISOFS_INVALID_MODE;
897 
898 	/*
899 	 * Read the root inode, which _may_ result in changing
900 	 * the s_rock flag. Once we have the final s_rock value,
901 	 * we then decide whether to use the Joliet descriptor.
902 	 */
903 	inode = isofs_iget(s, sbi->s_firstdatazone, 0);
904 	if (IS_ERR(inode))
905 		goto out_no_root;
906 
907 	/*
908 	 * Fix for broken CDs with Rock Ridge and empty ISO root directory but
909 	 * correct Joliet root directory.
910 	 */
911 	if (sbi->s_rock == 1 && joliet_level &&
912 				rootdir_empty(s, sbi->s_firstdatazone)) {
913 		printk(KERN_NOTICE
914 			"ISOFS: primary root directory is empty. "
915 			"Disabling Rock Ridge and switching to Joliet.");
916 		sbi->s_rock = 0;
917 	}
918 
919 	/*
920 	 * If this disk has both Rock Ridge and Joliet on it, then we
921 	 * want to use Rock Ridge by default.  This can be overridden
922 	 * by using the norock mount option.  There is still one other
923 	 * possibility that is not taken into account: a Rock Ridge
924 	 * CD with Unicode names.  Until someone sees such a beast, it
925 	 * will not be supported.
926 	 */
927 	if (sbi->s_rock == 1) {
928 		joliet_level = 0;
929 	} else if (joliet_level) {
930 		sbi->s_rock = 0;
931 		if (sbi->s_firstdatazone != first_data_zone) {
932 			sbi->s_firstdatazone = first_data_zone;
933 			printk(KERN_DEBUG
934 				"ISOFS: changing to secondary root\n");
935 			iput(inode);
936 			inode = isofs_iget(s, sbi->s_firstdatazone, 0);
937 			if (IS_ERR(inode))
938 				goto out_no_root;
939 		}
940 	}
941 
942 	if (opt.check == 'u') {
943 		/* Only Joliet is case insensitive by default */
944 		if (joliet_level)
945 			opt.check = 'r';
946 		else
947 			opt.check = 's';
948 	}
949 	sbi->s_joliet_level = joliet_level;
950 
951 	/* Make sure the root inode is a directory */
952 	if (!S_ISDIR(inode->i_mode)) {
953 		printk(KERN_WARNING
954 			"isofs_fill_super: root inode is not a directory. "
955 			"Corrupted media?\n");
956 		goto out_iput;
957 	}
958 
959 	table = 0;
960 	if (joliet_level)
961 		table += 2;
962 	if (opt.check == 'r')
963 		table++;
964 	sbi->s_check = opt.check;
965 
966 	if (table)
967 		s->s_d_op = &isofs_dentry_ops[table - 1];
968 
969 	/* get the root dentry */
970 	s->s_root = d_make_root(inode);
971 	if (!(s->s_root)) {
972 		error = -ENOMEM;
973 		goto out_no_inode;
974 	}
975 
976 	kfree(opt.iocharset);
977 
978 	return 0;
979 
980 	/*
981 	 * Display error messages and free resources.
982 	 */
983 out_iput:
984 	iput(inode);
985 	goto out_no_inode;
986 out_no_root:
987 	error = PTR_ERR(inode);
988 	if (error != -ENOMEM)
989 		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
990 out_no_inode:
991 #ifdef CONFIG_JOLIET
992 	unload_nls(sbi->s_nls_iocharset);
993 #endif
994 	goto out_freesbi;
995 out_no_read:
996 	printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
997 		__func__, s->s_id, iso_blknum, block);
998 	goto out_freebh;
999 out_bad_zone_size:
1000 	printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
1001 		sbi->s_log_zone_size);
1002 	goto out_freebh;
1003 out_bad_size:
1004 	printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
1005 		orig_zonesize, opt.blocksize);
1006 	goto out_freebh;
1007 out_unknown_format:
1008 	if (!silent)
1009 		printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
1010 
1011 out_freebh:
1012 	brelse(bh);
1013 	brelse(pri_bh);
1014 out_freesbi:
1015 	kfree(opt.iocharset);
1016 	kfree(sbi);
1017 	s->s_fs_info = NULL;
1018 	return error;
1019 }
1020 
1021 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
1022 {
1023 	struct super_block *sb = dentry->d_sb;
1024 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1025 
1026 	buf->f_type = ISOFS_SUPER_MAGIC;
1027 	buf->f_bsize = sb->s_blocksize;
1028 	buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1029 		<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1030 	buf->f_bfree = 0;
1031 	buf->f_bavail = 0;
1032 	buf->f_files = ISOFS_SB(sb)->s_ninodes;
1033 	buf->f_ffree = 0;
1034 	buf->f_fsid.val[0] = (u32)id;
1035 	buf->f_fsid.val[1] = (u32)(id >> 32);
1036 	buf->f_namelen = NAME_MAX;
1037 	return 0;
1038 }
1039 
1040 /*
1041  * Get a set of blocks; filling in buffer_heads if already allocated
1042  * or getblk() if they are not.  Returns the number of blocks inserted
1043  * (-ve == error.)
1044  */
1045 int isofs_get_blocks(struct inode *inode, sector_t iblock,
1046 		     struct buffer_head **bh, unsigned long nblocks)
1047 {
1048 	unsigned long b_off = iblock;
1049 	unsigned offset, sect_size;
1050 	unsigned int firstext;
1051 	unsigned long nextblk, nextoff;
1052 	int section, rv, error;
1053 	struct iso_inode_info *ei = ISOFS_I(inode);
1054 
1055 	error = -EIO;
1056 	rv = 0;
1057 	if (iblock != b_off) {
1058 		printk(KERN_DEBUG "%s: block number too large\n", __func__);
1059 		goto abort;
1060 	}
1061 
1062 
1063 	offset = 0;
1064 	firstext = ei->i_first_extent;
1065 	sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1066 	nextblk = ei->i_next_section_block;
1067 	nextoff = ei->i_next_section_offset;
1068 	section = 0;
1069 
1070 	while (nblocks) {
1071 		/* If we are *way* beyond the end of the file, print a message.
1072 		 * Access beyond the end of the file up to the next page boundary
1073 		 * is normal, however because of the way the page cache works.
1074 		 * In this case, we just return 0 so that we can properly fill
1075 		 * the page with useless information without generating any
1076 		 * I/O errors.
1077 		 */
1078 		if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1079 			printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1080 				__func__, b_off,
1081 				(unsigned long long)inode->i_size);
1082 			goto abort;
1083 		}
1084 
1085 		/* On the last section, nextblk == 0, section size is likely to
1086 		 * exceed sect_size by a partial block, and access beyond the
1087 		 * end of the file will reach beyond the section size, too.
1088 		 */
1089 		while (nextblk && (b_off >= (offset + sect_size))) {
1090 			struct inode *ninode;
1091 
1092 			offset += sect_size;
1093 			ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1094 			if (IS_ERR(ninode)) {
1095 				error = PTR_ERR(ninode);
1096 				goto abort;
1097 			}
1098 			firstext  = ISOFS_I(ninode)->i_first_extent;
1099 			sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1100 			nextblk   = ISOFS_I(ninode)->i_next_section_block;
1101 			nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1102 			iput(ninode);
1103 
1104 			if (++section > 100) {
1105 				printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1106 					" aborting...\n", __func__);
1107 				printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1108 					"nextblk=%lu nextoff=%lu\n", __func__,
1109 					b_off, firstext, (unsigned) sect_size,
1110 					nextblk, nextoff);
1111 				goto abort;
1112 			}
1113 		}
1114 
1115 		if (*bh) {
1116 			map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1117 		} else {
1118 			*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1119 			if (!*bh)
1120 				goto abort;
1121 		}
1122 		bh++;	/* Next buffer head */
1123 		b_off++;	/* Next buffer offset */
1124 		nblocks--;
1125 		rv++;
1126 	}
1127 
1128 	error = 0;
1129 abort:
1130 	return rv != 0 ? rv : error;
1131 }
1132 
1133 /*
1134  * Used by the standard interfaces.
1135  */
1136 static int isofs_get_block(struct inode *inode, sector_t iblock,
1137 		    struct buffer_head *bh_result, int create)
1138 {
1139 	int ret;
1140 
1141 	if (create) {
1142 		printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1143 		return -EROFS;
1144 	}
1145 
1146 	ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1147 	return ret < 0 ? ret : 0;
1148 }
1149 
1150 static int isofs_bmap(struct inode *inode, sector_t block)
1151 {
1152 	struct buffer_head dummy;
1153 	int error;
1154 
1155 	dummy.b_state = 0;
1156 	dummy.b_blocknr = -1000;
1157 	error = isofs_get_block(inode, block, &dummy, 0);
1158 	if (!error)
1159 		return dummy.b_blocknr;
1160 	return 0;
1161 }
1162 
1163 struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1164 {
1165 	sector_t blknr = isofs_bmap(inode, block);
1166 	if (!blknr)
1167 		return NULL;
1168 	return sb_bread(inode->i_sb, blknr);
1169 }
1170 
1171 static int isofs_readpage(struct file *file, struct page *page)
1172 {
1173 	return mpage_readpage(page, isofs_get_block);
1174 }
1175 
1176 static int isofs_readpages(struct file *file, struct address_space *mapping,
1177 			struct list_head *pages, unsigned nr_pages)
1178 {
1179 	return mpage_readpages(mapping, pages, nr_pages, isofs_get_block);
1180 }
1181 
1182 static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1183 {
1184 	return generic_block_bmap(mapping,block,isofs_get_block);
1185 }
1186 
1187 static const struct address_space_operations isofs_aops = {
1188 	.readpage = isofs_readpage,
1189 	.readpages = isofs_readpages,
1190 	.bmap = _isofs_bmap
1191 };
1192 
1193 static int isofs_read_level3_size(struct inode *inode)
1194 {
1195 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1196 	int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1197 	struct buffer_head *bh = NULL;
1198 	unsigned long block, offset, block_saved, offset_saved;
1199 	int i = 0;
1200 	int more_entries = 0;
1201 	struct iso_directory_record *tmpde = NULL;
1202 	struct iso_inode_info *ei = ISOFS_I(inode);
1203 
1204 	inode->i_size = 0;
1205 
1206 	/* The first 16 blocks are reserved as the System Area.  Thus,
1207 	 * no inodes can appear in block 0.  We use this to flag that
1208 	 * this is the last section. */
1209 	ei->i_next_section_block = 0;
1210 	ei->i_next_section_offset = 0;
1211 
1212 	block = ei->i_iget5_block;
1213 	offset = ei->i_iget5_offset;
1214 
1215 	do {
1216 		struct iso_directory_record *de;
1217 		unsigned int de_len;
1218 
1219 		if (!bh) {
1220 			bh = sb_bread(inode->i_sb, block);
1221 			if (!bh)
1222 				goto out_noread;
1223 		}
1224 		de = (struct iso_directory_record *) (bh->b_data + offset);
1225 		de_len = *(unsigned char *) de;
1226 
1227 		if (de_len == 0) {
1228 			brelse(bh);
1229 			bh = NULL;
1230 			++block;
1231 			offset = 0;
1232 			continue;
1233 		}
1234 
1235 		block_saved = block;
1236 		offset_saved = offset;
1237 		offset += de_len;
1238 
1239 		/* Make sure we have a full directory entry */
1240 		if (offset >= bufsize) {
1241 			int slop = bufsize - offset + de_len;
1242 			if (!tmpde) {
1243 				tmpde = kmalloc(256, GFP_KERNEL);
1244 				if (!tmpde)
1245 					goto out_nomem;
1246 			}
1247 			memcpy(tmpde, de, slop);
1248 			offset &= bufsize - 1;
1249 			block++;
1250 			brelse(bh);
1251 			bh = NULL;
1252 			if (offset) {
1253 				bh = sb_bread(inode->i_sb, block);
1254 				if (!bh)
1255 					goto out_noread;
1256 				memcpy((void *)tmpde+slop, bh->b_data, offset);
1257 			}
1258 			de = tmpde;
1259 		}
1260 
1261 		inode->i_size += isonum_733(de->size);
1262 		if (i == 1) {
1263 			ei->i_next_section_block = block_saved;
1264 			ei->i_next_section_offset = offset_saved;
1265 		}
1266 
1267 		more_entries = de->flags[-high_sierra] & 0x80;
1268 
1269 		i++;
1270 		if (i > 100)
1271 			goto out_toomany;
1272 	} while (more_entries);
1273 out:
1274 	kfree(tmpde);
1275 	if (bh)
1276 		brelse(bh);
1277 	return 0;
1278 
1279 out_nomem:
1280 	if (bh)
1281 		brelse(bh);
1282 	return -ENOMEM;
1283 
1284 out_noread:
1285 	printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1286 	kfree(tmpde);
1287 	return -EIO;
1288 
1289 out_toomany:
1290 	printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1291 		"isofs_read_level3_size: inode=%lu\n",
1292 		__func__, inode->i_ino);
1293 	goto out;
1294 }
1295 
1296 static int isofs_read_inode(struct inode *inode, int relocated)
1297 {
1298 	struct super_block *sb = inode->i_sb;
1299 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
1300 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1301 	unsigned long block;
1302 	int high_sierra = sbi->s_high_sierra;
1303 	struct buffer_head *bh;
1304 	struct iso_directory_record *de;
1305 	struct iso_directory_record *tmpde = NULL;
1306 	unsigned int de_len;
1307 	unsigned long offset;
1308 	struct iso_inode_info *ei = ISOFS_I(inode);
1309 	int ret = -EIO;
1310 
1311 	block = ei->i_iget5_block;
1312 	bh = sb_bread(inode->i_sb, block);
1313 	if (!bh)
1314 		goto out_badread;
1315 
1316 	offset = ei->i_iget5_offset;
1317 
1318 	de = (struct iso_directory_record *) (bh->b_data + offset);
1319 	de_len = *(unsigned char *) de;
1320 
1321 	if (offset + de_len > bufsize) {
1322 		int frag1 = bufsize - offset;
1323 
1324 		tmpde = kmalloc(de_len, GFP_KERNEL);
1325 		if (!tmpde) {
1326 			ret = -ENOMEM;
1327 			goto fail;
1328 		}
1329 		memcpy(tmpde, bh->b_data + offset, frag1);
1330 		brelse(bh);
1331 		bh = sb_bread(inode->i_sb, ++block);
1332 		if (!bh)
1333 			goto out_badread;
1334 		memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1335 		de = tmpde;
1336 	}
1337 
1338 	inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1339 					ei->i_iget5_offset,
1340 					ISOFS_BUFFER_BITS(inode));
1341 
1342 	/* Assume it is a normal-format file unless told otherwise */
1343 	ei->i_file_format = isofs_file_normal;
1344 
1345 	if (de->flags[-high_sierra] & 2) {
1346 		if (sbi->s_dmode != ISOFS_INVALID_MODE)
1347 			inode->i_mode = S_IFDIR | sbi->s_dmode;
1348 		else
1349 			inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1350 		set_nlink(inode, 1);	/*
1351 					 * Set to 1.  We know there are 2, but
1352 					 * the find utility tries to optimize
1353 					 * if it is 2, and it screws up.  It is
1354 					 * easier to give 1 which tells find to
1355 					 * do it the hard way.
1356 					 */
1357 	} else {
1358 		if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1359 			inode->i_mode = S_IFREG | sbi->s_fmode;
1360 		} else {
1361 			/*
1362 			 * Set default permissions: r-x for all.  The disc
1363 			 * could be shared with DOS machines so virtually
1364 			 * anything could be a valid executable.
1365 			 */
1366 			inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1367 		}
1368 		set_nlink(inode, 1);
1369 	}
1370 	inode->i_uid = sbi->s_uid;
1371 	inode->i_gid = sbi->s_gid;
1372 	inode->i_blocks = 0;
1373 
1374 	ei->i_format_parm[0] = 0;
1375 	ei->i_format_parm[1] = 0;
1376 	ei->i_format_parm[2] = 0;
1377 
1378 	ei->i_section_size = isonum_733(de->size);
1379 	if (de->flags[-high_sierra] & 0x80) {
1380 		ret = isofs_read_level3_size(inode);
1381 		if (ret < 0)
1382 			goto fail;
1383 		ret = -EIO;
1384 	} else {
1385 		ei->i_next_section_block = 0;
1386 		ei->i_next_section_offset = 0;
1387 		inode->i_size = isonum_733(de->size);
1388 	}
1389 
1390 	/*
1391 	 * Some dipshit decided to store some other bit of information
1392 	 * in the high byte of the file length.  Truncate size in case
1393 	 * this CDROM was mounted with the cruft option.
1394 	 */
1395 
1396 	if (sbi->s_cruft)
1397 		inode->i_size &= 0x00ffffff;
1398 
1399 	if (de->interleave[0]) {
1400 		printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1401 		inode->i_size = 0;
1402 	}
1403 
1404 	/* I have no idea what file_unit_size is used for, so
1405 	   we will flag it for now */
1406 	if (de->file_unit_size[0] != 0) {
1407 		printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1408 			inode->i_ino);
1409 	}
1410 
1411 	/* I have no idea what other flag bits are used for, so
1412 	   we will flag it for now */
1413 #ifdef DEBUG
1414 	if((de->flags[-high_sierra] & ~2)!= 0){
1415 		printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1416 				"(%ld %x).\n",
1417 			inode->i_ino, de->flags[-high_sierra]);
1418 	}
1419 #endif
1420 
1421 	inode->i_mtime.tv_sec =
1422 	inode->i_atime.tv_sec =
1423 	inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
1424 	inode->i_mtime.tv_nsec =
1425 	inode->i_atime.tv_nsec =
1426 	inode->i_ctime.tv_nsec = 0;
1427 
1428 	ei->i_first_extent = (isonum_733(de->extent) +
1429 			isonum_711(de->ext_attr_length));
1430 
1431 	/* Set the number of blocks for stat() - should be done before RR */
1432 	inode->i_blocks = (inode->i_size + 511) >> 9;
1433 
1434 	/*
1435 	 * Now test for possible Rock Ridge extensions which will override
1436 	 * some of these numbers in the inode structure.
1437 	 */
1438 
1439 	if (!high_sierra) {
1440 		parse_rock_ridge_inode(de, inode, relocated);
1441 		/* if we want uid/gid set, override the rock ridge setting */
1442 		if (sbi->s_uid_set)
1443 			inode->i_uid = sbi->s_uid;
1444 		if (sbi->s_gid_set)
1445 			inode->i_gid = sbi->s_gid;
1446 	}
1447 	/* Now set final access rights if overriding rock ridge setting */
1448 	if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1449 	    sbi->s_dmode != ISOFS_INVALID_MODE)
1450 		inode->i_mode = S_IFDIR | sbi->s_dmode;
1451 	if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1452 	    sbi->s_fmode != ISOFS_INVALID_MODE)
1453 		inode->i_mode = S_IFREG | sbi->s_fmode;
1454 
1455 	/* Install the inode operations vector */
1456 	if (S_ISREG(inode->i_mode)) {
1457 		inode->i_fop = &generic_ro_fops;
1458 		switch (ei->i_file_format) {
1459 #ifdef CONFIG_ZISOFS
1460 		case isofs_file_compressed:
1461 			inode->i_data.a_ops = &zisofs_aops;
1462 			break;
1463 #endif
1464 		default:
1465 			inode->i_data.a_ops = &isofs_aops;
1466 			break;
1467 		}
1468 	} else if (S_ISDIR(inode->i_mode)) {
1469 		inode->i_op = &isofs_dir_inode_operations;
1470 		inode->i_fop = &isofs_dir_operations;
1471 	} else if (S_ISLNK(inode->i_mode)) {
1472 		inode->i_op = &page_symlink_inode_operations;
1473 		inode_nohighmem(inode);
1474 		inode->i_data.a_ops = &isofs_symlink_aops;
1475 	} else
1476 		/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1477 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1478 
1479 	ret = 0;
1480 out:
1481 	kfree(tmpde);
1482 	if (bh)
1483 		brelse(bh);
1484 	return ret;
1485 
1486 out_badread:
1487 	printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1488 fail:
1489 	goto out;
1490 }
1491 
1492 struct isofs_iget5_callback_data {
1493 	unsigned long block;
1494 	unsigned long offset;
1495 };
1496 
1497 static int isofs_iget5_test(struct inode *ino, void *data)
1498 {
1499 	struct iso_inode_info *i = ISOFS_I(ino);
1500 	struct isofs_iget5_callback_data *d =
1501 		(struct isofs_iget5_callback_data*)data;
1502 	return (i->i_iget5_block == d->block)
1503 		&& (i->i_iget5_offset == d->offset);
1504 }
1505 
1506 static int isofs_iget5_set(struct inode *ino, void *data)
1507 {
1508 	struct iso_inode_info *i = ISOFS_I(ino);
1509 	struct isofs_iget5_callback_data *d =
1510 		(struct isofs_iget5_callback_data*)data;
1511 	i->i_iget5_block = d->block;
1512 	i->i_iget5_offset = d->offset;
1513 	return 0;
1514 }
1515 
1516 /* Store, in the inode's containing structure, the block and block
1517  * offset that point to the underlying meta-data for the inode.  The
1518  * code below is otherwise similar to the iget() code in
1519  * include/linux/fs.h */
1520 struct inode *__isofs_iget(struct super_block *sb,
1521 			   unsigned long block,
1522 			   unsigned long offset,
1523 			   int relocated)
1524 {
1525 	unsigned long hashval;
1526 	struct inode *inode;
1527 	struct isofs_iget5_callback_data data;
1528 	long ret;
1529 
1530 	if (offset >= 1ul << sb->s_blocksize_bits)
1531 		return ERR_PTR(-EINVAL);
1532 
1533 	data.block = block;
1534 	data.offset = offset;
1535 
1536 	hashval = (block << sb->s_blocksize_bits) | offset;
1537 
1538 	inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1539 				&isofs_iget5_set, &data);
1540 
1541 	if (!inode)
1542 		return ERR_PTR(-ENOMEM);
1543 
1544 	if (inode->i_state & I_NEW) {
1545 		ret = isofs_read_inode(inode, relocated);
1546 		if (ret < 0) {
1547 			iget_failed(inode);
1548 			inode = ERR_PTR(ret);
1549 		} else {
1550 			unlock_new_inode(inode);
1551 		}
1552 	}
1553 
1554 	return inode;
1555 }
1556 
1557 static struct dentry *isofs_mount(struct file_system_type *fs_type,
1558 	int flags, const char *dev_name, void *data)
1559 {
1560 	return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1561 }
1562 
1563 static struct file_system_type iso9660_fs_type = {
1564 	.owner		= THIS_MODULE,
1565 	.name		= "iso9660",
1566 	.mount		= isofs_mount,
1567 	.kill_sb	= kill_block_super,
1568 	.fs_flags	= FS_REQUIRES_DEV,
1569 };
1570 MODULE_ALIAS_FS("iso9660");
1571 MODULE_ALIAS("iso9660");
1572 
1573 static int __init init_iso9660_fs(void)
1574 {
1575 	int err = init_inodecache();
1576 	if (err)
1577 		goto out;
1578 #ifdef CONFIG_ZISOFS
1579 	err = zisofs_init();
1580 	if (err)
1581 		goto out1;
1582 #endif
1583 	err = register_filesystem(&iso9660_fs_type);
1584 	if (err)
1585 		goto out2;
1586 	return 0;
1587 out2:
1588 #ifdef CONFIG_ZISOFS
1589 	zisofs_cleanup();
1590 out1:
1591 #endif
1592 	destroy_inodecache();
1593 out:
1594 	return err;
1595 }
1596 
1597 static void __exit exit_iso9660_fs(void)
1598 {
1599         unregister_filesystem(&iso9660_fs_type);
1600 #ifdef CONFIG_ZISOFS
1601 	zisofs_cleanup();
1602 #endif
1603 	destroy_inodecache();
1604 }
1605 
1606 module_init(init_iso9660_fs)
1607 module_exit(exit_iso9660_fs)
1608 MODULE_LICENSE("GPL");
1609