xref: /linux/fs/isofs/inode.c (revision bdaedca74d6293b6ac643a8ebe8231b52bf1171b)
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 /* max tz offset is 13 hours */
34 #define MAX_TZ_OFFSET (52*15*60)
35 
36 #define BEQUIET
37 
38 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
39 static int isofs_dentry_cmpi(const struct dentry *dentry,
40 		unsigned int len, const char *str, const struct qstr *name);
41 
42 #ifdef CONFIG_JOLIET
43 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
44 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
45 static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
46 		unsigned int len, const char *str, const struct qstr *name);
47 static int isofs_dentry_cmp_ms(const struct dentry *dentry,
48 		unsigned int len, const char *str, const struct qstr *name);
49 #endif
50 
51 static void isofs_put_super(struct super_block *sb)
52 {
53 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
54 
55 #ifdef CONFIG_JOLIET
56 	unload_nls(sbi->s_nls_iocharset);
57 #endif
58 
59 	kfree(sbi);
60 	sb->s_fs_info = NULL;
61 	return;
62 }
63 
64 static int isofs_read_inode(struct inode *, int relocated);
65 static int isofs_statfs (struct dentry *, struct kstatfs *);
66 static int isofs_show_options(struct seq_file *, struct dentry *);
67 
68 static struct kmem_cache *isofs_inode_cachep;
69 
70 static struct inode *isofs_alloc_inode(struct super_block *sb)
71 {
72 	struct iso_inode_info *ei;
73 	ei = kmem_cache_alloc(isofs_inode_cachep, GFP_KERNEL);
74 	if (!ei)
75 		return NULL;
76 	return &ei->vfs_inode;
77 }
78 
79 static void isofs_free_inode(struct inode *inode)
80 {
81 	kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
82 }
83 
84 static void init_once(void *foo)
85 {
86 	struct iso_inode_info *ei = foo;
87 
88 	inode_init_once(&ei->vfs_inode);
89 }
90 
91 static int __init init_inodecache(void)
92 {
93 	isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
94 					sizeof(struct iso_inode_info),
95 					0, (SLAB_RECLAIM_ACCOUNT|
96 					SLAB_MEM_SPREAD|SLAB_ACCOUNT),
97 					init_once);
98 	if (!isofs_inode_cachep)
99 		return -ENOMEM;
100 	return 0;
101 }
102 
103 static void destroy_inodecache(void)
104 {
105 	/*
106 	 * Make sure all delayed rcu free inodes are flushed before we
107 	 * destroy cache.
108 	 */
109 	rcu_barrier();
110 	kmem_cache_destroy(isofs_inode_cachep);
111 }
112 
113 static int isofs_remount(struct super_block *sb, int *flags, char *data)
114 {
115 	sync_filesystem(sb);
116 	if (!(*flags & SB_RDONLY))
117 		return -EROFS;
118 	return 0;
119 }
120 
121 static const struct super_operations isofs_sops = {
122 	.alloc_inode	= isofs_alloc_inode,
123 	.free_inode	= isofs_free_inode,
124 	.put_super	= isofs_put_super,
125 	.statfs		= isofs_statfs,
126 	.remount_fs	= isofs_remount,
127 	.show_options	= isofs_show_options,
128 };
129 
130 
131 static const struct dentry_operations isofs_dentry_ops[] = {
132 	{
133 		.d_hash		= isofs_hashi,
134 		.d_compare	= isofs_dentry_cmpi,
135 	},
136 #ifdef CONFIG_JOLIET
137 	{
138 		.d_hash		= isofs_hash_ms,
139 		.d_compare	= isofs_dentry_cmp_ms,
140 	},
141 	{
142 		.d_hash		= isofs_hashi_ms,
143 		.d_compare	= isofs_dentry_cmpi_ms,
144 	},
145 #endif
146 };
147 
148 struct iso9660_options{
149 	unsigned int rock:1;
150 	unsigned int joliet:1;
151 	unsigned int cruft:1;
152 	unsigned int hide:1;
153 	unsigned int showassoc:1;
154 	unsigned int nocompress:1;
155 	unsigned int overriderockperm:1;
156 	unsigned int uid_set:1;
157 	unsigned int gid_set:1;
158 	unsigned int utf8:1;
159 	unsigned char map;
160 	unsigned char check;
161 	unsigned int blocksize;
162 	umode_t fmode;
163 	umode_t dmode;
164 	kgid_t gid;
165 	kuid_t uid;
166 	char *iocharset;
167 	/* LVE */
168 	s32 session;
169 	s32 sbsector;
170 };
171 
172 /*
173  * Compute the hash for the isofs name corresponding to the dentry.
174  */
175 static int
176 isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
177 {
178 	const char *name;
179 	int len;
180 	char c;
181 	unsigned long hash;
182 
183 	len = qstr->len;
184 	name = qstr->name;
185 	if (ms) {
186 		while (len && name[len-1] == '.')
187 			len--;
188 	}
189 
190 	hash = init_name_hash(dentry);
191 	while (len--) {
192 		c = tolower(*name++);
193 		hash = partial_name_hash(c, hash);
194 	}
195 	qstr->hash = end_name_hash(hash);
196 
197 	return 0;
198 }
199 
200 /*
201  * Compare of two isofs names.
202  */
203 static int isofs_dentry_cmp_common(
204 		unsigned int len, const char *str,
205 		const struct qstr *name, int ms, int ci)
206 {
207 	int alen, blen;
208 
209 	/* A filename cannot end in '.' or we treat it like it has none */
210 	alen = name->len;
211 	blen = len;
212 	if (ms) {
213 		while (alen && name->name[alen-1] == '.')
214 			alen--;
215 		while (blen && str[blen-1] == '.')
216 			blen--;
217 	}
218 	if (alen == blen) {
219 		if (ci) {
220 			if (strncasecmp(name->name, str, alen) == 0)
221 				return 0;
222 		} else {
223 			if (strncmp(name->name, str, alen) == 0)
224 				return 0;
225 		}
226 	}
227 	return 1;
228 }
229 
230 static int
231 isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
232 {
233 	return isofs_hashi_common(dentry, qstr, 0);
234 }
235 
236 static int
237 isofs_dentry_cmpi(const struct dentry *dentry,
238 		unsigned int len, const char *str, const struct qstr *name)
239 {
240 	return isofs_dentry_cmp_common(len, str, name, 0, 1);
241 }
242 
243 #ifdef CONFIG_JOLIET
244 /*
245  * Compute the hash for the isofs name corresponding to the dentry.
246  */
247 static int
248 isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
249 {
250 	const char *name;
251 	int len;
252 
253 	len = qstr->len;
254 	name = qstr->name;
255 	if (ms) {
256 		while (len && name[len-1] == '.')
257 			len--;
258 	}
259 
260 	qstr->hash = full_name_hash(dentry, name, len);
261 
262 	return 0;
263 }
264 
265 static int
266 isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
267 {
268 	return isofs_hash_common(dentry, qstr, 1);
269 }
270 
271 static int
272 isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
273 {
274 	return isofs_hashi_common(dentry, qstr, 1);
275 }
276 
277 static int
278 isofs_dentry_cmp_ms(const struct dentry *dentry,
279 		unsigned int len, const char *str, const struct qstr *name)
280 {
281 	return isofs_dentry_cmp_common(len, str, name, 1, 0);
282 }
283 
284 static int
285 isofs_dentry_cmpi_ms(const struct dentry *dentry,
286 		unsigned int len, const char *str, const struct qstr *name)
287 {
288 	return isofs_dentry_cmp_common(len, str, name, 1, 1);
289 }
290 #endif
291 
292 enum {
293 	Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
294 	Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
295 	Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
296 	Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
297 };
298 
299 static const match_table_t tokens = {
300 	{Opt_norock, "norock"},
301 	{Opt_nojoliet, "nojoliet"},
302 	{Opt_unhide, "unhide"},
303 	{Opt_hide, "hide"},
304 	{Opt_showassoc, "showassoc"},
305 	{Opt_cruft, "cruft"},
306 	{Opt_utf8, "utf8"},
307 	{Opt_iocharset, "iocharset=%s"},
308 	{Opt_map_a, "map=acorn"},
309 	{Opt_map_a, "map=a"},
310 	{Opt_map_n, "map=normal"},
311 	{Opt_map_n, "map=n"},
312 	{Opt_map_o, "map=off"},
313 	{Opt_map_o, "map=o"},
314 	{Opt_session, "session=%u"},
315 	{Opt_sb, "sbsector=%u"},
316 	{Opt_check_r, "check=relaxed"},
317 	{Opt_check_r, "check=r"},
318 	{Opt_check_s, "check=strict"},
319 	{Opt_check_s, "check=s"},
320 	{Opt_uid, "uid=%u"},
321 	{Opt_gid, "gid=%u"},
322 	{Opt_mode, "mode=%u"},
323 	{Opt_dmode, "dmode=%u"},
324 	{Opt_overriderockperm, "overriderockperm"},
325 	{Opt_block, "block=%u"},
326 	{Opt_ignore, "conv=binary"},
327 	{Opt_ignore, "conv=b"},
328 	{Opt_ignore, "conv=text"},
329 	{Opt_ignore, "conv=t"},
330 	{Opt_ignore, "conv=mtext"},
331 	{Opt_ignore, "conv=m"},
332 	{Opt_ignore, "conv=auto"},
333 	{Opt_ignore, "conv=a"},
334 	{Opt_nocompress, "nocompress"},
335 	{Opt_err, NULL}
336 };
337 
338 static int parse_options(char *options, struct iso9660_options *popt)
339 {
340 	char *p;
341 	int option;
342 	unsigned int uv;
343 
344 	popt->map = 'n';
345 	popt->rock = 1;
346 	popt->joliet = 1;
347 	popt->cruft = 0;
348 	popt->hide = 0;
349 	popt->showassoc = 0;
350 	popt->check = 'u';		/* unset */
351 	popt->nocompress = 0;
352 	popt->blocksize = 1024;
353 	popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
354 	popt->uid_set = 0;
355 	popt->gid_set = 0;
356 	popt->gid = GLOBAL_ROOT_GID;
357 	popt->uid = GLOBAL_ROOT_UID;
358 	popt->iocharset = NULL;
359 	popt->utf8 = 0;
360 	popt->overriderockperm = 0;
361 	popt->session=-1;
362 	popt->sbsector=-1;
363 	if (!options)
364 		return 1;
365 
366 	while ((p = strsep(&options, ",")) != NULL) {
367 		int token;
368 		substring_t args[MAX_OPT_ARGS];
369 		unsigned n;
370 
371 		if (!*p)
372 			continue;
373 
374 		token = match_token(p, tokens, args);
375 		switch (token) {
376 		case Opt_norock:
377 			popt->rock = 0;
378 			break;
379 		case Opt_nojoliet:
380 			popt->joliet = 0;
381 			break;
382 		case Opt_hide:
383 			popt->hide = 1;
384 			break;
385 		case Opt_unhide:
386 		case Opt_showassoc:
387 			popt->showassoc = 1;
388 			break;
389 		case Opt_cruft:
390 			popt->cruft = 1;
391 			break;
392 		case Opt_utf8:
393 			popt->utf8 = 1;
394 			break;
395 #ifdef CONFIG_JOLIET
396 		case Opt_iocharset:
397 			kfree(popt->iocharset);
398 			popt->iocharset = match_strdup(&args[0]);
399 			if (!popt->iocharset)
400 				return 0;
401 			break;
402 #endif
403 		case Opt_map_a:
404 			popt->map = 'a';
405 			break;
406 		case Opt_map_o:
407 			popt->map = 'o';
408 			break;
409 		case Opt_map_n:
410 			popt->map = 'n';
411 			break;
412 		case Opt_session:
413 			if (match_int(&args[0], &option))
414 				return 0;
415 			n = option;
416 			/*
417 			 * Track numbers are supposed to be in range 1-99, the
418 			 * mount option starts indexing at 0.
419 			 */
420 			if (n >= 99)
421 				return 0;
422 			popt->session = n + 1;
423 			break;
424 		case Opt_sb:
425 			if (match_int(&args[0], &option))
426 				return 0;
427 			popt->sbsector = option;
428 			break;
429 		case Opt_check_r:
430 			popt->check = 'r';
431 			break;
432 		case Opt_check_s:
433 			popt->check = 's';
434 			break;
435 		case Opt_ignore:
436 			break;
437 		case Opt_uid:
438 			if (match_uint(&args[0], &uv))
439 				return 0;
440 			popt->uid = make_kuid(current_user_ns(), uv);
441 			if (!uid_valid(popt->uid))
442 				return 0;
443 			popt->uid_set = 1;
444 			break;
445 		case Opt_gid:
446 			if (match_uint(&args[0], &uv))
447 				return 0;
448 			popt->gid = make_kgid(current_user_ns(), uv);
449 			if (!gid_valid(popt->gid))
450 				return 0;
451 			popt->gid_set = 1;
452 			break;
453 		case Opt_mode:
454 			if (match_int(&args[0], &option))
455 				return 0;
456 			popt->fmode = option;
457 			break;
458 		case Opt_dmode:
459 			if (match_int(&args[0], &option))
460 				return 0;
461 			popt->dmode = option;
462 			break;
463 		case Opt_overriderockperm:
464 			popt->overriderockperm = 1;
465 			break;
466 		case Opt_block:
467 			if (match_int(&args[0], &option))
468 				return 0;
469 			n = option;
470 			if (n != 512 && n != 1024 && n != 2048)
471 				return 0;
472 			popt->blocksize = n;
473 			break;
474 		case Opt_nocompress:
475 			popt->nocompress = 1;
476 			break;
477 		default:
478 			return 0;
479 		}
480 	}
481 	return 1;
482 }
483 
484 /*
485  * Display the mount options in /proc/mounts.
486  */
487 static int isofs_show_options(struct seq_file *m, struct dentry *root)
488 {
489 	struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
490 
491 	if (!sbi->s_rock)		seq_puts(m, ",norock");
492 	else if (!sbi->s_joliet_level)	seq_puts(m, ",nojoliet");
493 	if (sbi->s_cruft)		seq_puts(m, ",cruft");
494 	if (sbi->s_hide)		seq_puts(m, ",hide");
495 	if (sbi->s_nocompress)		seq_puts(m, ",nocompress");
496 	if (sbi->s_overriderockperm)	seq_puts(m, ",overriderockperm");
497 	if (sbi->s_showassoc)		seq_puts(m, ",showassoc");
498 	if (sbi->s_utf8)		seq_puts(m, ",utf8");
499 
500 	if (sbi->s_check)		seq_printf(m, ",check=%c", sbi->s_check);
501 	if (sbi->s_mapping)		seq_printf(m, ",map=%c", sbi->s_mapping);
502 	if (sbi->s_session != 255)	seq_printf(m, ",session=%u", sbi->s_session - 1);
503 	if (sbi->s_sbsector != -1)	seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
504 
505 	if (root->d_sb->s_blocksize != 1024)
506 		seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
507 
508 	if (sbi->s_uid_set)
509 		seq_printf(m, ",uid=%u",
510 			   from_kuid_munged(&init_user_ns, sbi->s_uid));
511 	if (sbi->s_gid_set)
512 		seq_printf(m, ",gid=%u",
513 			   from_kgid_munged(&init_user_ns, sbi->s_gid));
514 
515 	if (sbi->s_dmode != ISOFS_INVALID_MODE)
516 		seq_printf(m, ",dmode=%o", sbi->s_dmode);
517 	if (sbi->s_fmode != ISOFS_INVALID_MODE)
518 		seq_printf(m, ",fmode=%o", sbi->s_fmode);
519 
520 #ifdef CONFIG_JOLIET
521 	if (sbi->s_nls_iocharset &&
522 	    strcmp(sbi->s_nls_iocharset->charset, CONFIG_NLS_DEFAULT) != 0)
523 		seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
524 #endif
525 	return 0;
526 }
527 
528 /*
529  * look if the driver can tell the multi session redirection value
530  *
531  * don't change this if you don't know what you do, please!
532  * Multisession is legal only with XA disks.
533  * A non-XA disk with more than one volume descriptor may do it right, but
534  * usually is written in a nowhere standardized "multi-partition" manner.
535  * Multisession uses absolute addressing (solely the first frame of the whole
536  * track is #0), multi-partition uses relative addressing (each first frame of
537  * each track is #0), and a track is not a session.
538  *
539  * A broken CDwriter software or drive firmware does not set new standards,
540  * at least not if conflicting with the existing ones.
541  *
542  * emoenke@gwdg.de
543  */
544 #define WE_OBEY_THE_WRITTEN_STANDARDS 1
545 
546 static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
547 {
548 	struct cdrom_device_info *cdi = disk_to_cdi(sb->s_bdev->bd_disk);
549 	unsigned int vol_desc_start = 0;
550 
551 	if (session > 0) {
552 		struct cdrom_tocentry te;
553 
554 		if (!cdi)
555 			return 0;
556 
557 		te.cdte_track = session;
558 		te.cdte_format = CDROM_LBA;
559 		if (cdrom_read_tocentry(cdi, &te) == 0) {
560 			printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
561 				session, te.cdte_addr.lba,
562 				te.cdte_ctrl & CDROM_DATA_TRACK);
563 			if ((te.cdte_ctrl & CDROM_DATA_TRACK) == 4)
564 				return te.cdte_addr.lba;
565 		}
566 
567 		printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
568 	}
569 
570 	if (cdi) {
571 		struct cdrom_multisession ms_info;
572 
573 		ms_info.addr_format = CDROM_LBA;
574 		if (cdrom_multisession(cdi, &ms_info) == 0) {
575 #if WE_OBEY_THE_WRITTEN_STANDARDS
576 			/* necessary for a valid ms_info.addr */
577 			if (ms_info.xa_flag)
578 #endif
579 				vol_desc_start = ms_info.addr.lba;
580 		}
581 	}
582 
583 	return vol_desc_start;
584 }
585 
586 /*
587  * Check if root directory is empty (has less than 3 files).
588  *
589  * Used to detect broken CDs where ISO root directory is empty but Joliet root
590  * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
591  * (and Joliet used instead) or else no files would be visible.
592  */
593 static bool rootdir_empty(struct super_block *sb, unsigned long block)
594 {
595 	int offset = 0, files = 0, de_len;
596 	struct iso_directory_record *de;
597 	struct buffer_head *bh;
598 
599 	bh = sb_bread(sb, block);
600 	if (!bh)
601 		return true;
602 	while (files < 3) {
603 		de = (struct iso_directory_record *) (bh->b_data + offset);
604 		de_len = *(unsigned char *) de;
605 		if (de_len == 0)
606 			break;
607 		files++;
608 		offset += de_len;
609 	}
610 	brelse(bh);
611 	return files < 3;
612 }
613 
614 /*
615  * Initialize the superblock and read the root inode.
616  */
617 static int isofs_fill_super(struct super_block *s, void *data, int silent)
618 {
619 	struct buffer_head *bh = NULL, *pri_bh = NULL;
620 	struct hs_primary_descriptor *h_pri = NULL;
621 	struct iso_primary_descriptor *pri = NULL;
622 	struct iso_supplementary_descriptor *sec = NULL;
623 	struct iso_directory_record *rootp;
624 	struct inode *inode;
625 	struct iso9660_options opt;
626 	struct isofs_sb_info *sbi;
627 	unsigned long first_data_zone;
628 	int joliet_level = 0;
629 	int iso_blknum, block;
630 	int orig_zonesize;
631 	int table, error = -EINVAL;
632 	unsigned int vol_desc_start;
633 
634 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
635 	if (!sbi)
636 		return -ENOMEM;
637 	s->s_fs_info = sbi;
638 
639 	if (!parse_options((char *)data, &opt))
640 		goto out_freesbi;
641 
642 	/*
643 	 * First of all, get the hardware blocksize for this device.
644 	 * If we don't know what it is, or the hardware blocksize is
645 	 * larger than the blocksize the user specified, then use
646 	 * that value.
647 	 */
648 	/*
649 	 * What if bugger tells us to go beyond page size?
650 	 */
651 	if (bdev_logical_block_size(s->s_bdev) > 2048) {
652 		printk(KERN_WARNING
653 		       "ISOFS: unsupported/invalid hardware sector size %d\n",
654 			bdev_logical_block_size(s->s_bdev));
655 		goto out_freesbi;
656 	}
657 	opt.blocksize = sb_min_blocksize(s, opt.blocksize);
658 
659 	sbi->s_high_sierra = 0; /* default is iso9660 */
660 	sbi->s_session = opt.session;
661 	sbi->s_sbsector = opt.sbsector;
662 
663 	vol_desc_start = (opt.sbsector != -1) ?
664 		opt.sbsector : isofs_get_last_session(s,opt.session);
665 
666 	for (iso_blknum = vol_desc_start+16;
667 		iso_blknum < vol_desc_start+100; iso_blknum++) {
668 		struct hs_volume_descriptor *hdp;
669 		struct iso_volume_descriptor  *vdp;
670 
671 		block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
672 		if (!(bh = sb_bread(s, block)))
673 			goto out_no_read;
674 
675 		vdp = (struct iso_volume_descriptor *)bh->b_data;
676 		hdp = (struct hs_volume_descriptor *)bh->b_data;
677 
678 		/*
679 		 * Due to the overlapping physical location of the descriptors,
680 		 * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
681 		 * proper identification in this case, we first check for ISO.
682 		 */
683 		if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
684 			if (isonum_711(vdp->type) == ISO_VD_END)
685 				break;
686 			if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
687 				if (!pri) {
688 					pri = (struct iso_primary_descriptor *)vdp;
689 					/* Save the buffer in case we need it ... */
690 					pri_bh = bh;
691 					bh = NULL;
692 				}
693 			}
694 #ifdef CONFIG_JOLIET
695 			else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
696 				sec = (struct iso_supplementary_descriptor *)vdp;
697 				if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
698 					if (opt.joliet) {
699 						if (sec->escape[2] == 0x40)
700 							joliet_level = 1;
701 						else if (sec->escape[2] == 0x43)
702 							joliet_level = 2;
703 						else if (sec->escape[2] == 0x45)
704 							joliet_level = 3;
705 
706 						printk(KERN_DEBUG "ISO 9660 Extensions: "
707 							"Microsoft Joliet Level %d\n",
708 							joliet_level);
709 					}
710 					goto root_found;
711 				} else {
712 				/* Unknown supplementary volume descriptor */
713 				sec = NULL;
714 				}
715 			}
716 #endif
717 		} else {
718 			if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
719 				if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
720 					goto out_freebh;
721 
722 				sbi->s_high_sierra = 1;
723 				opt.rock = 0;
724 				h_pri = (struct hs_primary_descriptor *)vdp;
725 				goto root_found;
726 			}
727 		}
728 
729 		/* Just skip any volume descriptors we don't recognize */
730 
731 		brelse(bh);
732 		bh = NULL;
733 	}
734 	/*
735 	 * If we fall through, either no volume descriptor was found,
736 	 * or else we passed a primary descriptor looking for others.
737 	 */
738 	if (!pri)
739 		goto out_unknown_format;
740 	brelse(bh);
741 	bh = pri_bh;
742 	pri_bh = NULL;
743 
744 root_found:
745 	/* We don't support read-write mounts */
746 	if (!sb_rdonly(s)) {
747 		error = -EACCES;
748 		goto out_freebh;
749 	}
750 
751 	if (joliet_level && (!pri || !opt.rock)) {
752 		/* This is the case of Joliet with the norock mount flag.
753 		 * A disc with both Joliet and Rock Ridge is handled later
754 		 */
755 		pri = (struct iso_primary_descriptor *) sec;
756 	}
757 
758 	if(sbi->s_high_sierra){
759 		rootp = (struct iso_directory_record *) h_pri->root_directory_record;
760 		sbi->s_nzones = isonum_733(h_pri->volume_space_size);
761 		sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
762 		sbi->s_max_size = isonum_733(h_pri->volume_space_size);
763 	} else {
764 		if (!pri)
765 			goto out_freebh;
766 		rootp = (struct iso_directory_record *) pri->root_directory_record;
767 		sbi->s_nzones = isonum_733(pri->volume_space_size);
768 		sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
769 		sbi->s_max_size = isonum_733(pri->volume_space_size);
770 	}
771 
772 	sbi->s_ninodes = 0; /* No way to figure this out easily */
773 
774 	orig_zonesize = sbi->s_log_zone_size;
775 	/*
776 	 * If the zone size is smaller than the hardware sector size,
777 	 * this is a fatal error.  This would occur if the disc drive
778 	 * had sectors that were 2048 bytes, but the filesystem had
779 	 * blocks that were 512 bytes (which should only very rarely
780 	 * happen.)
781 	 */
782 	if (orig_zonesize < opt.blocksize)
783 		goto out_bad_size;
784 
785 	/* RDE: convert log zone size to bit shift */
786 	switch (sbi->s_log_zone_size) {
787 	case  512: sbi->s_log_zone_size =  9; break;
788 	case 1024: sbi->s_log_zone_size = 10; break;
789 	case 2048: sbi->s_log_zone_size = 11; break;
790 
791 	default:
792 		goto out_bad_zone_size;
793 	}
794 
795 	s->s_magic = ISOFS_SUPER_MAGIC;
796 
797 	/*
798 	 * With multi-extent files, file size is only limited by the maximum
799 	 * size of a file system, which is 8 TB.
800 	 */
801 	s->s_maxbytes = 0x80000000000LL;
802 
803 	/* ECMA-119 timestamp from 1900/1/1 with tz offset */
804 	s->s_time_min = mktime64(1900, 1, 1, 0, 0, 0) - MAX_TZ_OFFSET;
805 	s->s_time_max = mktime64(U8_MAX+1900, 12, 31, 23, 59, 59) + MAX_TZ_OFFSET;
806 
807 	/* Set this for reference. Its not currently used except on write
808 	   which we don't have .. */
809 
810 	first_data_zone = isonum_733(rootp->extent) +
811 			  isonum_711(rootp->ext_attr_length);
812 	sbi->s_firstdatazone = first_data_zone;
813 #ifndef BEQUIET
814 	printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
815 		sbi->s_max_size, 1UL << sbi->s_log_zone_size);
816 	printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
817 	if(sbi->s_high_sierra)
818 		printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
819 #endif
820 
821 	/*
822 	 * If the Joliet level is set, we _may_ decide to use the
823 	 * secondary descriptor, but can't be sure until after we
824 	 * read the root inode. But before reading the root inode
825 	 * we may need to change the device blocksize, and would
826 	 * rather release the old buffer first. So, we cache the
827 	 * first_data_zone value from the secondary descriptor.
828 	 */
829 	if (joliet_level) {
830 		pri = (struct iso_primary_descriptor *) sec;
831 		rootp = (struct iso_directory_record *)
832 			pri->root_directory_record;
833 		first_data_zone = isonum_733(rootp->extent) +
834 				isonum_711(rootp->ext_attr_length);
835 	}
836 
837 	/*
838 	 * We're all done using the volume descriptor, and may need
839 	 * to change the device blocksize, so release the buffer now.
840 	 */
841 	brelse(pri_bh);
842 	brelse(bh);
843 
844 	/*
845 	 * Force the blocksize to 512 for 512 byte sectors.  The file
846 	 * read primitives really get it wrong in a bad way if we don't
847 	 * do this.
848 	 *
849 	 * Note - we should never be setting the blocksize to something
850 	 * less than the hardware sector size for the device.  If we
851 	 * do, we would end up having to read larger buffers and split
852 	 * out portions to satisfy requests.
853 	 *
854 	 * Note2- the idea here is that we want to deal with the optimal
855 	 * zonesize in the filesystem.  If we have it set to something less,
856 	 * then we have horrible problems with trying to piece together
857 	 * bits of adjacent blocks in order to properly read directory
858 	 * entries.  By forcing the blocksize in this way, we ensure
859 	 * that we will never be required to do this.
860 	 */
861 	sb_set_blocksize(s, orig_zonesize);
862 
863 	sbi->s_nls_iocharset = NULL;
864 
865 #ifdef CONFIG_JOLIET
866 	if (joliet_level && opt.utf8 == 0) {
867 		char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
868 		sbi->s_nls_iocharset = load_nls(p);
869 		if (! sbi->s_nls_iocharset) {
870 			/* Fail only if explicit charset specified */
871 			if (opt.iocharset)
872 				goto out_freesbi;
873 			sbi->s_nls_iocharset = load_nls_default();
874 		}
875 	}
876 #endif
877 	s->s_op = &isofs_sops;
878 	s->s_export_op = &isofs_export_ops;
879 	sbi->s_mapping = opt.map;
880 	sbi->s_rock = (opt.rock ? 2 : 0);
881 	sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
882 	sbi->s_cruft = opt.cruft;
883 	sbi->s_hide = opt.hide;
884 	sbi->s_showassoc = opt.showassoc;
885 	sbi->s_uid = opt.uid;
886 	sbi->s_gid = opt.gid;
887 	sbi->s_uid_set = opt.uid_set;
888 	sbi->s_gid_set = opt.gid_set;
889 	sbi->s_utf8 = opt.utf8;
890 	sbi->s_nocompress = opt.nocompress;
891 	sbi->s_overriderockperm = opt.overriderockperm;
892 	/*
893 	 * It would be incredibly stupid to allow people to mark every file
894 	 * on the disk as suid, so we merely allow them to set the default
895 	 * permissions.
896 	 */
897 	if (opt.fmode != ISOFS_INVALID_MODE)
898 		sbi->s_fmode = opt.fmode & 0777;
899 	else
900 		sbi->s_fmode = ISOFS_INVALID_MODE;
901 	if (opt.dmode != ISOFS_INVALID_MODE)
902 		sbi->s_dmode = opt.dmode & 0777;
903 	else
904 		sbi->s_dmode = ISOFS_INVALID_MODE;
905 
906 	/*
907 	 * Read the root inode, which _may_ result in changing
908 	 * the s_rock flag. Once we have the final s_rock value,
909 	 * we then decide whether to use the Joliet descriptor.
910 	 */
911 	inode = isofs_iget(s, sbi->s_firstdatazone, 0);
912 	if (IS_ERR(inode))
913 		goto out_no_root;
914 
915 	/*
916 	 * Fix for broken CDs with Rock Ridge and empty ISO root directory but
917 	 * correct Joliet root directory.
918 	 */
919 	if (sbi->s_rock == 1 && joliet_level &&
920 				rootdir_empty(s, sbi->s_firstdatazone)) {
921 		printk(KERN_NOTICE
922 			"ISOFS: primary root directory is empty. "
923 			"Disabling Rock Ridge and switching to Joliet.");
924 		sbi->s_rock = 0;
925 	}
926 
927 	/*
928 	 * If this disk has both Rock Ridge and Joliet on it, then we
929 	 * want to use Rock Ridge by default.  This can be overridden
930 	 * by using the norock mount option.  There is still one other
931 	 * possibility that is not taken into account: a Rock Ridge
932 	 * CD with Unicode names.  Until someone sees such a beast, it
933 	 * will not be supported.
934 	 */
935 	if (sbi->s_rock == 1) {
936 		joliet_level = 0;
937 	} else if (joliet_level) {
938 		sbi->s_rock = 0;
939 		if (sbi->s_firstdatazone != first_data_zone) {
940 			sbi->s_firstdatazone = first_data_zone;
941 			printk(KERN_DEBUG
942 				"ISOFS: changing to secondary root\n");
943 			iput(inode);
944 			inode = isofs_iget(s, sbi->s_firstdatazone, 0);
945 			if (IS_ERR(inode))
946 				goto out_no_root;
947 		}
948 	}
949 
950 	if (opt.check == 'u') {
951 		/* Only Joliet is case insensitive by default */
952 		if (joliet_level)
953 			opt.check = 'r';
954 		else
955 			opt.check = 's';
956 	}
957 	sbi->s_joliet_level = joliet_level;
958 
959 	/* Make sure the root inode is a directory */
960 	if (!S_ISDIR(inode->i_mode)) {
961 		printk(KERN_WARNING
962 			"isofs_fill_super: root inode is not a directory. "
963 			"Corrupted media?\n");
964 		goto out_iput;
965 	}
966 
967 	table = 0;
968 	if (joliet_level)
969 		table += 2;
970 	if (opt.check == 'r')
971 		table++;
972 	sbi->s_check = opt.check;
973 
974 	if (table)
975 		s->s_d_op = &isofs_dentry_ops[table - 1];
976 
977 	/* get the root dentry */
978 	s->s_root = d_make_root(inode);
979 	if (!(s->s_root)) {
980 		error = -ENOMEM;
981 		goto out_no_inode;
982 	}
983 
984 	kfree(opt.iocharset);
985 
986 	return 0;
987 
988 	/*
989 	 * Display error messages and free resources.
990 	 */
991 out_iput:
992 	iput(inode);
993 	goto out_no_inode;
994 out_no_root:
995 	error = PTR_ERR(inode);
996 	if (error != -ENOMEM)
997 		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
998 out_no_inode:
999 #ifdef CONFIG_JOLIET
1000 	unload_nls(sbi->s_nls_iocharset);
1001 #endif
1002 	goto out_freesbi;
1003 out_no_read:
1004 	printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
1005 		__func__, s->s_id, iso_blknum, block);
1006 	goto out_freebh;
1007 out_bad_zone_size:
1008 	printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
1009 		sbi->s_log_zone_size);
1010 	goto out_freebh;
1011 out_bad_size:
1012 	printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
1013 		orig_zonesize, opt.blocksize);
1014 	goto out_freebh;
1015 out_unknown_format:
1016 	if (!silent)
1017 		printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
1018 
1019 out_freebh:
1020 	brelse(bh);
1021 	brelse(pri_bh);
1022 out_freesbi:
1023 	kfree(opt.iocharset);
1024 	kfree(sbi);
1025 	s->s_fs_info = NULL;
1026 	return error;
1027 }
1028 
1029 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
1030 {
1031 	struct super_block *sb = dentry->d_sb;
1032 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1033 
1034 	buf->f_type = ISOFS_SUPER_MAGIC;
1035 	buf->f_bsize = sb->s_blocksize;
1036 	buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1037 		<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1038 	buf->f_bfree = 0;
1039 	buf->f_bavail = 0;
1040 	buf->f_files = ISOFS_SB(sb)->s_ninodes;
1041 	buf->f_ffree = 0;
1042 	buf->f_fsid = u64_to_fsid(id);
1043 	buf->f_namelen = NAME_MAX;
1044 	return 0;
1045 }
1046 
1047 /*
1048  * Get a set of blocks; filling in buffer_heads if already allocated
1049  * or getblk() if they are not.  Returns the number of blocks inserted
1050  * (-ve == error.)
1051  */
1052 int isofs_get_blocks(struct inode *inode, sector_t iblock,
1053 		     struct buffer_head **bh, unsigned long nblocks)
1054 {
1055 	unsigned long b_off = iblock;
1056 	unsigned offset, sect_size;
1057 	unsigned int firstext;
1058 	unsigned long nextblk, nextoff;
1059 	int section, rv, error;
1060 	struct iso_inode_info *ei = ISOFS_I(inode);
1061 
1062 	error = -EIO;
1063 	rv = 0;
1064 	if (iblock != b_off) {
1065 		printk(KERN_DEBUG "%s: block number too large\n", __func__);
1066 		goto abort;
1067 	}
1068 
1069 
1070 	offset = 0;
1071 	firstext = ei->i_first_extent;
1072 	sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1073 	nextblk = ei->i_next_section_block;
1074 	nextoff = ei->i_next_section_offset;
1075 	section = 0;
1076 
1077 	while (nblocks) {
1078 		/* If we are *way* beyond the end of the file, print a message.
1079 		 * Access beyond the end of the file up to the next page boundary
1080 		 * is normal, however because of the way the page cache works.
1081 		 * In this case, we just return 0 so that we can properly fill
1082 		 * the page with useless information without generating any
1083 		 * I/O errors.
1084 		 */
1085 		if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1086 			printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1087 				__func__, b_off,
1088 				(unsigned long long)inode->i_size);
1089 			goto abort;
1090 		}
1091 
1092 		/* On the last section, nextblk == 0, section size is likely to
1093 		 * exceed sect_size by a partial block, and access beyond the
1094 		 * end of the file will reach beyond the section size, too.
1095 		 */
1096 		while (nextblk && (b_off >= (offset + sect_size))) {
1097 			struct inode *ninode;
1098 
1099 			offset += sect_size;
1100 			ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1101 			if (IS_ERR(ninode)) {
1102 				error = PTR_ERR(ninode);
1103 				goto abort;
1104 			}
1105 			firstext  = ISOFS_I(ninode)->i_first_extent;
1106 			sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1107 			nextblk   = ISOFS_I(ninode)->i_next_section_block;
1108 			nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1109 			iput(ninode);
1110 
1111 			if (++section > 100) {
1112 				printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1113 					" aborting...\n", __func__);
1114 				printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1115 					"nextblk=%lu nextoff=%lu\n", __func__,
1116 					b_off, firstext, (unsigned) sect_size,
1117 					nextblk, nextoff);
1118 				goto abort;
1119 			}
1120 		}
1121 
1122 		if (*bh) {
1123 			map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1124 		} else {
1125 			*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1126 			if (!*bh)
1127 				goto abort;
1128 		}
1129 		bh++;	/* Next buffer head */
1130 		b_off++;	/* Next buffer offset */
1131 		nblocks--;
1132 		rv++;
1133 	}
1134 
1135 	error = 0;
1136 abort:
1137 	return rv != 0 ? rv : error;
1138 }
1139 
1140 /*
1141  * Used by the standard interfaces.
1142  */
1143 static int isofs_get_block(struct inode *inode, sector_t iblock,
1144 		    struct buffer_head *bh_result, int create)
1145 {
1146 	int ret;
1147 
1148 	if (create) {
1149 		printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1150 		return -EROFS;
1151 	}
1152 
1153 	ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1154 	return ret < 0 ? ret : 0;
1155 }
1156 
1157 static int isofs_bmap(struct inode *inode, sector_t block)
1158 {
1159 	struct buffer_head dummy;
1160 	int error;
1161 
1162 	dummy.b_state = 0;
1163 	dummy.b_blocknr = -1000;
1164 	error = isofs_get_block(inode, block, &dummy, 0);
1165 	if (!error)
1166 		return dummy.b_blocknr;
1167 	return 0;
1168 }
1169 
1170 struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1171 {
1172 	sector_t blknr = isofs_bmap(inode, block);
1173 	if (!blknr)
1174 		return NULL;
1175 	return sb_bread(inode->i_sb, blknr);
1176 }
1177 
1178 static int isofs_readpage(struct file *file, struct page *page)
1179 {
1180 	return mpage_readpage(page, isofs_get_block);
1181 }
1182 
1183 static void isofs_readahead(struct readahead_control *rac)
1184 {
1185 	mpage_readahead(rac, isofs_get_block);
1186 }
1187 
1188 static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1189 {
1190 	return generic_block_bmap(mapping,block,isofs_get_block);
1191 }
1192 
1193 static const struct address_space_operations isofs_aops = {
1194 	.readpage = isofs_readpage,
1195 	.readahead = isofs_readahead,
1196 	.bmap = _isofs_bmap
1197 };
1198 
1199 static int isofs_read_level3_size(struct inode *inode)
1200 {
1201 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1202 	int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1203 	struct buffer_head *bh = NULL;
1204 	unsigned long block, offset, block_saved, offset_saved;
1205 	int i = 0;
1206 	int more_entries = 0;
1207 	struct iso_directory_record *tmpde = NULL;
1208 	struct iso_inode_info *ei = ISOFS_I(inode);
1209 
1210 	inode->i_size = 0;
1211 
1212 	/* The first 16 blocks are reserved as the System Area.  Thus,
1213 	 * no inodes can appear in block 0.  We use this to flag that
1214 	 * this is the last section. */
1215 	ei->i_next_section_block = 0;
1216 	ei->i_next_section_offset = 0;
1217 
1218 	block = ei->i_iget5_block;
1219 	offset = ei->i_iget5_offset;
1220 
1221 	do {
1222 		struct iso_directory_record *de;
1223 		unsigned int de_len;
1224 
1225 		if (!bh) {
1226 			bh = sb_bread(inode->i_sb, block);
1227 			if (!bh)
1228 				goto out_noread;
1229 		}
1230 		de = (struct iso_directory_record *) (bh->b_data + offset);
1231 		de_len = *(unsigned char *) de;
1232 
1233 		if (de_len == 0) {
1234 			brelse(bh);
1235 			bh = NULL;
1236 			++block;
1237 			offset = 0;
1238 			continue;
1239 		}
1240 
1241 		block_saved = block;
1242 		offset_saved = offset;
1243 		offset += de_len;
1244 
1245 		/* Make sure we have a full directory entry */
1246 		if (offset >= bufsize) {
1247 			int slop = bufsize - offset + de_len;
1248 			if (!tmpde) {
1249 				tmpde = kmalloc(256, GFP_KERNEL);
1250 				if (!tmpde)
1251 					goto out_nomem;
1252 			}
1253 			memcpy(tmpde, de, slop);
1254 			offset &= bufsize - 1;
1255 			block++;
1256 			brelse(bh);
1257 			bh = NULL;
1258 			if (offset) {
1259 				bh = sb_bread(inode->i_sb, block);
1260 				if (!bh)
1261 					goto out_noread;
1262 				memcpy((void *)tmpde+slop, bh->b_data, offset);
1263 			}
1264 			de = tmpde;
1265 		}
1266 
1267 		inode->i_size += isonum_733(de->size);
1268 		if (i == 1) {
1269 			ei->i_next_section_block = block_saved;
1270 			ei->i_next_section_offset = offset_saved;
1271 		}
1272 
1273 		more_entries = de->flags[-high_sierra] & 0x80;
1274 
1275 		i++;
1276 		if (i > 100)
1277 			goto out_toomany;
1278 	} while (more_entries);
1279 out:
1280 	kfree(tmpde);
1281 	if (bh)
1282 		brelse(bh);
1283 	return 0;
1284 
1285 out_nomem:
1286 	if (bh)
1287 		brelse(bh);
1288 	return -ENOMEM;
1289 
1290 out_noread:
1291 	printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1292 	kfree(tmpde);
1293 	return -EIO;
1294 
1295 out_toomany:
1296 	printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1297 		"isofs_read_level3_size: inode=%lu\n",
1298 		__func__, inode->i_ino);
1299 	goto out;
1300 }
1301 
1302 static int isofs_read_inode(struct inode *inode, int relocated)
1303 {
1304 	struct super_block *sb = inode->i_sb;
1305 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
1306 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1307 	unsigned long block;
1308 	int high_sierra = sbi->s_high_sierra;
1309 	struct buffer_head *bh;
1310 	struct iso_directory_record *de;
1311 	struct iso_directory_record *tmpde = NULL;
1312 	unsigned int de_len;
1313 	unsigned long offset;
1314 	struct iso_inode_info *ei = ISOFS_I(inode);
1315 	int ret = -EIO;
1316 
1317 	block = ei->i_iget5_block;
1318 	bh = sb_bread(inode->i_sb, block);
1319 	if (!bh)
1320 		goto out_badread;
1321 
1322 	offset = ei->i_iget5_offset;
1323 
1324 	de = (struct iso_directory_record *) (bh->b_data + offset);
1325 	de_len = *(unsigned char *) de;
1326 
1327 	if (offset + de_len > bufsize) {
1328 		int frag1 = bufsize - offset;
1329 
1330 		tmpde = kmalloc(de_len, GFP_KERNEL);
1331 		if (!tmpde) {
1332 			ret = -ENOMEM;
1333 			goto fail;
1334 		}
1335 		memcpy(tmpde, bh->b_data + offset, frag1);
1336 		brelse(bh);
1337 		bh = sb_bread(inode->i_sb, ++block);
1338 		if (!bh)
1339 			goto out_badread;
1340 		memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1341 		de = tmpde;
1342 	}
1343 
1344 	inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1345 					ei->i_iget5_offset,
1346 					ISOFS_BUFFER_BITS(inode));
1347 
1348 	/* Assume it is a normal-format file unless told otherwise */
1349 	ei->i_file_format = isofs_file_normal;
1350 
1351 	if (de->flags[-high_sierra] & 2) {
1352 		if (sbi->s_dmode != ISOFS_INVALID_MODE)
1353 			inode->i_mode = S_IFDIR | sbi->s_dmode;
1354 		else
1355 			inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1356 		set_nlink(inode, 1);	/*
1357 					 * Set to 1.  We know there are 2, but
1358 					 * the find utility tries to optimize
1359 					 * if it is 2, and it screws up.  It is
1360 					 * easier to give 1 which tells find to
1361 					 * do it the hard way.
1362 					 */
1363 	} else {
1364 		if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1365 			inode->i_mode = S_IFREG | sbi->s_fmode;
1366 		} else {
1367 			/*
1368 			 * Set default permissions: r-x for all.  The disc
1369 			 * could be shared with DOS machines so virtually
1370 			 * anything could be a valid executable.
1371 			 */
1372 			inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1373 		}
1374 		set_nlink(inode, 1);
1375 	}
1376 	inode->i_uid = sbi->s_uid;
1377 	inode->i_gid = sbi->s_gid;
1378 	inode->i_blocks = 0;
1379 
1380 	ei->i_format_parm[0] = 0;
1381 	ei->i_format_parm[1] = 0;
1382 	ei->i_format_parm[2] = 0;
1383 
1384 	ei->i_section_size = isonum_733(de->size);
1385 	if (de->flags[-high_sierra] & 0x80) {
1386 		ret = isofs_read_level3_size(inode);
1387 		if (ret < 0)
1388 			goto fail;
1389 		ret = -EIO;
1390 	} else {
1391 		ei->i_next_section_block = 0;
1392 		ei->i_next_section_offset = 0;
1393 		inode->i_size = isonum_733(de->size);
1394 	}
1395 
1396 	/*
1397 	 * Some dipshit decided to store some other bit of information
1398 	 * in the high byte of the file length.  Truncate size in case
1399 	 * this CDROM was mounted with the cruft option.
1400 	 */
1401 
1402 	if (sbi->s_cruft)
1403 		inode->i_size &= 0x00ffffff;
1404 
1405 	if (de->interleave[0]) {
1406 		printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1407 		inode->i_size = 0;
1408 	}
1409 
1410 	/* I have no idea what file_unit_size is used for, so
1411 	   we will flag it for now */
1412 	if (de->file_unit_size[0] != 0) {
1413 		printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1414 			inode->i_ino);
1415 	}
1416 
1417 	/* I have no idea what other flag bits are used for, so
1418 	   we will flag it for now */
1419 #ifdef DEBUG
1420 	if((de->flags[-high_sierra] & ~2)!= 0){
1421 		printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1422 				"(%ld %x).\n",
1423 			inode->i_ino, de->flags[-high_sierra]);
1424 	}
1425 #endif
1426 
1427 	inode->i_mtime.tv_sec =
1428 	inode->i_atime.tv_sec =
1429 	inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
1430 	inode->i_mtime.tv_nsec =
1431 	inode->i_atime.tv_nsec =
1432 	inode->i_ctime.tv_nsec = 0;
1433 
1434 	ei->i_first_extent = (isonum_733(de->extent) +
1435 			isonum_711(de->ext_attr_length));
1436 
1437 	/* Set the number of blocks for stat() - should be done before RR */
1438 	inode->i_blocks = (inode->i_size + 511) >> 9;
1439 
1440 	/*
1441 	 * Now test for possible Rock Ridge extensions which will override
1442 	 * some of these numbers in the inode structure.
1443 	 */
1444 
1445 	if (!high_sierra) {
1446 		parse_rock_ridge_inode(de, inode, relocated);
1447 		/* if we want uid/gid set, override the rock ridge setting */
1448 		if (sbi->s_uid_set)
1449 			inode->i_uid = sbi->s_uid;
1450 		if (sbi->s_gid_set)
1451 			inode->i_gid = sbi->s_gid;
1452 	}
1453 	/* Now set final access rights if overriding rock ridge setting */
1454 	if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1455 	    sbi->s_dmode != ISOFS_INVALID_MODE)
1456 		inode->i_mode = S_IFDIR | sbi->s_dmode;
1457 	if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1458 	    sbi->s_fmode != ISOFS_INVALID_MODE)
1459 		inode->i_mode = S_IFREG | sbi->s_fmode;
1460 
1461 	/* Install the inode operations vector */
1462 	if (S_ISREG(inode->i_mode)) {
1463 		inode->i_fop = &generic_ro_fops;
1464 		switch (ei->i_file_format) {
1465 #ifdef CONFIG_ZISOFS
1466 		case isofs_file_compressed:
1467 			inode->i_data.a_ops = &zisofs_aops;
1468 			break;
1469 #endif
1470 		default:
1471 			inode->i_data.a_ops = &isofs_aops;
1472 			break;
1473 		}
1474 	} else if (S_ISDIR(inode->i_mode)) {
1475 		inode->i_op = &isofs_dir_inode_operations;
1476 		inode->i_fop = &isofs_dir_operations;
1477 	} else if (S_ISLNK(inode->i_mode)) {
1478 		inode->i_op = &page_symlink_inode_operations;
1479 		inode_nohighmem(inode);
1480 		inode->i_data.a_ops = &isofs_symlink_aops;
1481 	} else
1482 		/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1483 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1484 
1485 	ret = 0;
1486 out:
1487 	kfree(tmpde);
1488 	if (bh)
1489 		brelse(bh);
1490 	return ret;
1491 
1492 out_badread:
1493 	printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1494 fail:
1495 	goto out;
1496 }
1497 
1498 struct isofs_iget5_callback_data {
1499 	unsigned long block;
1500 	unsigned long offset;
1501 };
1502 
1503 static int isofs_iget5_test(struct inode *ino, void *data)
1504 {
1505 	struct iso_inode_info *i = ISOFS_I(ino);
1506 	struct isofs_iget5_callback_data *d =
1507 		(struct isofs_iget5_callback_data*)data;
1508 	return (i->i_iget5_block == d->block)
1509 		&& (i->i_iget5_offset == d->offset);
1510 }
1511 
1512 static int isofs_iget5_set(struct inode *ino, void *data)
1513 {
1514 	struct iso_inode_info *i = ISOFS_I(ino);
1515 	struct isofs_iget5_callback_data *d =
1516 		(struct isofs_iget5_callback_data*)data;
1517 	i->i_iget5_block = d->block;
1518 	i->i_iget5_offset = d->offset;
1519 	return 0;
1520 }
1521 
1522 /* Store, in the inode's containing structure, the block and block
1523  * offset that point to the underlying meta-data for the inode.  The
1524  * code below is otherwise similar to the iget() code in
1525  * include/linux/fs.h */
1526 struct inode *__isofs_iget(struct super_block *sb,
1527 			   unsigned long block,
1528 			   unsigned long offset,
1529 			   int relocated)
1530 {
1531 	unsigned long hashval;
1532 	struct inode *inode;
1533 	struct isofs_iget5_callback_data data;
1534 	long ret;
1535 
1536 	if (offset >= 1ul << sb->s_blocksize_bits)
1537 		return ERR_PTR(-EINVAL);
1538 
1539 	data.block = block;
1540 	data.offset = offset;
1541 
1542 	hashval = (block << sb->s_blocksize_bits) | offset;
1543 
1544 	inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1545 				&isofs_iget5_set, &data);
1546 
1547 	if (!inode)
1548 		return ERR_PTR(-ENOMEM);
1549 
1550 	if (inode->i_state & I_NEW) {
1551 		ret = isofs_read_inode(inode, relocated);
1552 		if (ret < 0) {
1553 			iget_failed(inode);
1554 			inode = ERR_PTR(ret);
1555 		} else {
1556 			unlock_new_inode(inode);
1557 		}
1558 	}
1559 
1560 	return inode;
1561 }
1562 
1563 static struct dentry *isofs_mount(struct file_system_type *fs_type,
1564 	int flags, const char *dev_name, void *data)
1565 {
1566 	return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1567 }
1568 
1569 static struct file_system_type iso9660_fs_type = {
1570 	.owner		= THIS_MODULE,
1571 	.name		= "iso9660",
1572 	.mount		= isofs_mount,
1573 	.kill_sb	= kill_block_super,
1574 	.fs_flags	= FS_REQUIRES_DEV,
1575 };
1576 MODULE_ALIAS_FS("iso9660");
1577 MODULE_ALIAS("iso9660");
1578 
1579 static int __init init_iso9660_fs(void)
1580 {
1581 	int err = init_inodecache();
1582 	if (err)
1583 		goto out;
1584 #ifdef CONFIG_ZISOFS
1585 	err = zisofs_init();
1586 	if (err)
1587 		goto out1;
1588 #endif
1589 	err = register_filesystem(&iso9660_fs_type);
1590 	if (err)
1591 		goto out2;
1592 	return 0;
1593 out2:
1594 #ifdef CONFIG_ZISOFS
1595 	zisofs_cleanup();
1596 out1:
1597 #endif
1598 	destroy_inodecache();
1599 out:
1600 	return err;
1601 }
1602 
1603 static void __exit exit_iso9660_fs(void)
1604 {
1605         unregister_filesystem(&iso9660_fs_type);
1606 #ifdef CONFIG_ZISOFS
1607 	zisofs_cleanup();
1608 #endif
1609 	destroy_inodecache();
1610 }
1611 
1612 module_init(init_iso9660_fs)
1613 module_exit(exit_iso9660_fs)
1614 MODULE_LICENSE("GPL");
1615