xref: /openbmc/linux/fs/isofs/inode.c (revision 5bd8e16d)
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/nls.h>
19 #include <linux/ctype.h>
20 #include <linux/statfs.h>
21 #include <linux/cdrom.h>
22 #include <linux/parser.h>
23 #include <linux/mpage.h>
24 #include <linux/user_namespace.h>
25 
26 #include "isofs.h"
27 #include "zisofs.h"
28 
29 #define BEQUIET
30 
31 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
32 static int isofs_hash(const struct dentry *parent, struct qstr *qstr);
33 static int isofs_dentry_cmpi(const struct dentry *parent,
34 		const struct dentry *dentry,
35 		unsigned int len, const char *str, const struct qstr *name);
36 static int isofs_dentry_cmp(const struct dentry *parent,
37 		const struct dentry *dentry,
38 		unsigned int len, const char *str, const struct qstr *name);
39 
40 #ifdef CONFIG_JOLIET
41 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
42 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
43 static int isofs_dentry_cmpi_ms(const struct dentry *parent,
44 		const struct dentry *dentry,
45 		unsigned int len, const char *str, const struct qstr *name);
46 static int isofs_dentry_cmp_ms(const struct dentry *parent,
47 		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 *);
65 static int isofs_statfs (struct dentry *, struct kstatfs *);
66 
67 static struct kmem_cache *isofs_inode_cachep;
68 
69 static struct inode *isofs_alloc_inode(struct super_block *sb)
70 {
71 	struct iso_inode_info *ei;
72 	ei = kmem_cache_alloc(isofs_inode_cachep, GFP_KERNEL);
73 	if (!ei)
74 		return NULL;
75 	return &ei->vfs_inode;
76 }
77 
78 static void isofs_i_callback(struct rcu_head *head)
79 {
80 	struct inode *inode = container_of(head, struct inode, i_rcu);
81 	kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
82 }
83 
84 static void isofs_destroy_inode(struct inode *inode)
85 {
86 	call_rcu(&inode->i_rcu, isofs_i_callback);
87 }
88 
89 static void init_once(void *foo)
90 {
91 	struct iso_inode_info *ei = foo;
92 
93 	inode_init_once(&ei->vfs_inode);
94 }
95 
96 static int init_inodecache(void)
97 {
98 	isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
99 					sizeof(struct iso_inode_info),
100 					0, (SLAB_RECLAIM_ACCOUNT|
101 					SLAB_MEM_SPREAD),
102 					init_once);
103 	if (isofs_inode_cachep == NULL)
104 		return -ENOMEM;
105 	return 0;
106 }
107 
108 static void destroy_inodecache(void)
109 {
110 	/*
111 	 * Make sure all delayed rcu free inodes are flushed before we
112 	 * destroy cache.
113 	 */
114 	rcu_barrier();
115 	kmem_cache_destroy(isofs_inode_cachep);
116 }
117 
118 static int isofs_remount(struct super_block *sb, int *flags, char *data)
119 {
120 	if (!(*flags & MS_RDONLY))
121 		return -EROFS;
122 	return 0;
123 }
124 
125 static const struct super_operations isofs_sops = {
126 	.alloc_inode	= isofs_alloc_inode,
127 	.destroy_inode	= isofs_destroy_inode,
128 	.put_super	= isofs_put_super,
129 	.statfs		= isofs_statfs,
130 	.remount_fs	= isofs_remount,
131 	.show_options	= generic_show_options,
132 };
133 
134 
135 static const struct dentry_operations isofs_dentry_ops[] = {
136 	{
137 		.d_hash		= isofs_hash,
138 		.d_compare	= isofs_dentry_cmp,
139 	},
140 	{
141 		.d_hash		= isofs_hashi,
142 		.d_compare	= isofs_dentry_cmpi,
143 	},
144 #ifdef CONFIG_JOLIET
145 	{
146 		.d_hash		= isofs_hash_ms,
147 		.d_compare	= isofs_dentry_cmp_ms,
148 	},
149 	{
150 		.d_hash		= isofs_hashi_ms,
151 		.d_compare	= isofs_dentry_cmpi_ms,
152 	},
153 #endif
154 };
155 
156 struct iso9660_options{
157 	unsigned int rock:1;
158 	unsigned int joliet:1;
159 	unsigned int cruft:1;
160 	unsigned int hide:1;
161 	unsigned int showassoc:1;
162 	unsigned int nocompress:1;
163 	unsigned int overriderockperm:1;
164 	unsigned int uid_set:1;
165 	unsigned int gid_set:1;
166 	unsigned int utf8:1;
167 	unsigned char map;
168 	unsigned char check;
169 	unsigned int blocksize;
170 	umode_t fmode;
171 	umode_t dmode;
172 	kgid_t gid;
173 	kuid_t uid;
174 	char *iocharset;
175 	/* LVE */
176 	s32 session;
177 	s32 sbsector;
178 };
179 
180 /*
181  * Compute the hash for the isofs name corresponding to the dentry.
182  */
183 static int
184 isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
185 {
186 	const char *name;
187 	int len;
188 
189 	len = qstr->len;
190 	name = qstr->name;
191 	if (ms) {
192 		while (len && name[len-1] == '.')
193 			len--;
194 	}
195 
196 	qstr->hash = full_name_hash(name, len);
197 
198 	return 0;
199 }
200 
201 /*
202  * Compute the hash for the isofs name corresponding to the dentry.
203  */
204 static int
205 isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
206 {
207 	const char *name;
208 	int len;
209 	char c;
210 	unsigned long hash;
211 
212 	len = qstr->len;
213 	name = qstr->name;
214 	if (ms) {
215 		while (len && name[len-1] == '.')
216 			len--;
217 	}
218 
219 	hash = init_name_hash();
220 	while (len--) {
221 		c = tolower(*name++);
222 		hash = partial_name_hash(c, hash);
223 	}
224 	qstr->hash = end_name_hash(hash);
225 
226 	return 0;
227 }
228 
229 /*
230  * Compare of two isofs names.
231  */
232 static int isofs_dentry_cmp_common(
233 		unsigned int len, const char *str,
234 		const struct qstr *name, int ms, int ci)
235 {
236 	int alen, blen;
237 
238 	/* A filename cannot end in '.' or we treat it like it has none */
239 	alen = name->len;
240 	blen = len;
241 	if (ms) {
242 		while (alen && name->name[alen-1] == '.')
243 			alen--;
244 		while (blen && str[blen-1] == '.')
245 			blen--;
246 	}
247 	if (alen == blen) {
248 		if (ci) {
249 			if (strnicmp(name->name, str, alen) == 0)
250 				return 0;
251 		} else {
252 			if (strncmp(name->name, str, alen) == 0)
253 				return 0;
254 		}
255 	}
256 	return 1;
257 }
258 
259 static int
260 isofs_hash(const struct dentry *dentry, struct qstr *qstr)
261 {
262 	return isofs_hash_common(dentry, qstr, 0);
263 }
264 
265 static int
266 isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
267 {
268 	return isofs_hashi_common(dentry, qstr, 0);
269 }
270 
271 static int
272 isofs_dentry_cmp(const struct dentry *parent, const struct dentry *dentry,
273 		unsigned int len, const char *str, const struct qstr *name)
274 {
275 	return isofs_dentry_cmp_common(len, str, name, 0, 0);
276 }
277 
278 static int
279 isofs_dentry_cmpi(const struct dentry *parent, 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, 0, 1);
283 }
284 
285 #ifdef CONFIG_JOLIET
286 static int
287 isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
288 {
289 	return isofs_hash_common(dentry, qstr, 1);
290 }
291 
292 static int
293 isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
294 {
295 	return isofs_hashi_common(dentry, qstr, 1);
296 }
297 
298 static int
299 isofs_dentry_cmp_ms(const struct dentry *parent, const struct dentry *dentry,
300 		unsigned int len, const char *str, const struct qstr *name)
301 {
302 	return isofs_dentry_cmp_common(len, str, name, 1, 0);
303 }
304 
305 static int
306 isofs_dentry_cmpi_ms(const struct dentry *parent, const struct dentry *dentry,
307 		unsigned int len, const char *str, const struct qstr *name)
308 {
309 	return isofs_dentry_cmp_common(len, str, name, 1, 1);
310 }
311 #endif
312 
313 enum {
314 	Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
315 	Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
316 	Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
317 	Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
318 };
319 
320 static const match_table_t tokens = {
321 	{Opt_norock, "norock"},
322 	{Opt_nojoliet, "nojoliet"},
323 	{Opt_unhide, "unhide"},
324 	{Opt_hide, "hide"},
325 	{Opt_showassoc, "showassoc"},
326 	{Opt_cruft, "cruft"},
327 	{Opt_utf8, "utf8"},
328 	{Opt_iocharset, "iocharset=%s"},
329 	{Opt_map_a, "map=acorn"},
330 	{Opt_map_a, "map=a"},
331 	{Opt_map_n, "map=normal"},
332 	{Opt_map_n, "map=n"},
333 	{Opt_map_o, "map=off"},
334 	{Opt_map_o, "map=o"},
335 	{Opt_session, "session=%u"},
336 	{Opt_sb, "sbsector=%u"},
337 	{Opt_check_r, "check=relaxed"},
338 	{Opt_check_r, "check=r"},
339 	{Opt_check_s, "check=strict"},
340 	{Opt_check_s, "check=s"},
341 	{Opt_uid, "uid=%u"},
342 	{Opt_gid, "gid=%u"},
343 	{Opt_mode, "mode=%u"},
344 	{Opt_dmode, "dmode=%u"},
345 	{Opt_overriderockperm, "overriderockperm"},
346 	{Opt_block, "block=%u"},
347 	{Opt_ignore, "conv=binary"},
348 	{Opt_ignore, "conv=b"},
349 	{Opt_ignore, "conv=text"},
350 	{Opt_ignore, "conv=t"},
351 	{Opt_ignore, "conv=mtext"},
352 	{Opt_ignore, "conv=m"},
353 	{Opt_ignore, "conv=auto"},
354 	{Opt_ignore, "conv=a"},
355 	{Opt_nocompress, "nocompress"},
356 	{Opt_err, NULL}
357 };
358 
359 static int parse_options(char *options, struct iso9660_options *popt)
360 {
361 	char *p;
362 	int option;
363 
364 	popt->map = 'n';
365 	popt->rock = 1;
366 	popt->joliet = 1;
367 	popt->cruft = 0;
368 	popt->hide = 0;
369 	popt->showassoc = 0;
370 	popt->check = 'u';		/* unset */
371 	popt->nocompress = 0;
372 	popt->blocksize = 1024;
373 	popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
374 	popt->uid_set = 0;
375 	popt->gid_set = 0;
376 	popt->gid = GLOBAL_ROOT_GID;
377 	popt->uid = GLOBAL_ROOT_UID;
378 	popt->iocharset = NULL;
379 	popt->utf8 = 0;
380 	popt->overriderockperm = 0;
381 	popt->session=-1;
382 	popt->sbsector=-1;
383 	if (!options)
384 		return 1;
385 
386 	while ((p = strsep(&options, ",")) != NULL) {
387 		int token;
388 		substring_t args[MAX_OPT_ARGS];
389 		unsigned n;
390 
391 		if (!*p)
392 			continue;
393 
394 		token = match_token(p, tokens, args);
395 		switch (token) {
396 		case Opt_norock:
397 			popt->rock = 0;
398 			break;
399 		case Opt_nojoliet:
400 			popt->joliet = 0;
401 			break;
402 		case Opt_hide:
403 			popt->hide = 1;
404 			break;
405 		case Opt_unhide:
406 		case Opt_showassoc:
407 			popt->showassoc = 1;
408 			break;
409 		case Opt_cruft:
410 			popt->cruft = 1;
411 			break;
412 		case Opt_utf8:
413 			popt->utf8 = 1;
414 			break;
415 #ifdef CONFIG_JOLIET
416 		case Opt_iocharset:
417 			popt->iocharset = match_strdup(&args[0]);
418 			break;
419 #endif
420 		case Opt_map_a:
421 			popt->map = 'a';
422 			break;
423 		case Opt_map_o:
424 			popt->map = 'o';
425 			break;
426 		case Opt_map_n:
427 			popt->map = 'n';
428 			break;
429 		case Opt_session:
430 			if (match_int(&args[0], &option))
431 				return 0;
432 			n = option;
433 			if (n > 99)
434 				return 0;
435 			popt->session = n + 1;
436 			break;
437 		case Opt_sb:
438 			if (match_int(&args[0], &option))
439 				return 0;
440 			popt->sbsector = option;
441 			break;
442 		case Opt_check_r:
443 			popt->check = 'r';
444 			break;
445 		case Opt_check_s:
446 			popt->check = 's';
447 			break;
448 		case Opt_ignore:
449 			break;
450 		case Opt_uid:
451 			if (match_int(&args[0], &option))
452 				return 0;
453 			popt->uid = make_kuid(current_user_ns(), option);
454 			if (!uid_valid(popt->uid))
455 				return 0;
456 			popt->uid_set = 1;
457 			break;
458 		case Opt_gid:
459 			if (match_int(&args[0], &option))
460 				return 0;
461 			popt->gid = make_kgid(current_user_ns(), option);
462 			if (!gid_valid(popt->gid))
463 				return 0;
464 			popt->gid_set = 1;
465 			break;
466 		case Opt_mode:
467 			if (match_int(&args[0], &option))
468 				return 0;
469 			popt->fmode = option;
470 			break;
471 		case Opt_dmode:
472 			if (match_int(&args[0], &option))
473 				return 0;
474 			popt->dmode = option;
475 			break;
476 		case Opt_overriderockperm:
477 			popt->overriderockperm = 1;
478 			break;
479 		case Opt_block:
480 			if (match_int(&args[0], &option))
481 				return 0;
482 			n = option;
483 			if (n != 512 && n != 1024 && n != 2048)
484 				return 0;
485 			popt->blocksize = n;
486 			break;
487 		case Opt_nocompress:
488 			popt->nocompress = 1;
489 			break;
490 		default:
491 			return 0;
492 		}
493 	}
494 	return 1;
495 }
496 
497 /*
498  * look if the driver can tell the multi session redirection value
499  *
500  * don't change this if you don't know what you do, please!
501  * Multisession is legal only with XA disks.
502  * A non-XA disk with more than one volume descriptor may do it right, but
503  * usually is written in a nowhere standardized "multi-partition" manner.
504  * Multisession uses absolute addressing (solely the first frame of the whole
505  * track is #0), multi-partition uses relative addressing (each first frame of
506  * each track is #0), and a track is not a session.
507  *
508  * A broken CDwriter software or drive firmware does not set new standards,
509  * at least not if conflicting with the existing ones.
510  *
511  * emoenke@gwdg.de
512  */
513 #define WE_OBEY_THE_WRITTEN_STANDARDS 1
514 
515 static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
516 {
517 	struct cdrom_multisession ms_info;
518 	unsigned int vol_desc_start;
519 	struct block_device *bdev = sb->s_bdev;
520 	int i;
521 
522 	vol_desc_start=0;
523 	ms_info.addr_format=CDROM_LBA;
524 	if(session >= 0 && session <= 99) {
525 		struct cdrom_tocentry Te;
526 		Te.cdte_track=session;
527 		Te.cdte_format=CDROM_LBA;
528 		i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
529 		if (!i) {
530 			printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
531 				session, Te.cdte_addr.lba,
532 				Te.cdte_ctrl&CDROM_DATA_TRACK);
533 			if ((Te.cdte_ctrl&CDROM_DATA_TRACK) == 4)
534 				return Te.cdte_addr.lba;
535 		}
536 
537 		printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
538 	}
539 	i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long) &ms_info);
540 	if (session > 0)
541 		printk(KERN_ERR "ISOFS: Invalid session number\n");
542 #if 0
543 	printk(KERN_DEBUG "isofs.inode: CDROMMULTISESSION: rc=%d\n",i);
544 	if (i==0) {
545 		printk(KERN_DEBUG "isofs.inode: XA disk: %s\n",ms_info.xa_flag?"yes":"no");
546 		printk(KERN_DEBUG "isofs.inode: vol_desc_start = %d\n", ms_info.addr.lba);
547 	}
548 #endif
549 	if (i==0)
550 #if WE_OBEY_THE_WRITTEN_STANDARDS
551 		if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
552 #endif
553 			vol_desc_start=ms_info.addr.lba;
554 	return vol_desc_start;
555 }
556 
557 /*
558  * Check if root directory is empty (has less than 3 files).
559  *
560  * Used to detect broken CDs where ISO root directory is empty but Joliet root
561  * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
562  * (and Joliet used instead) or else no files would be visible.
563  */
564 static bool rootdir_empty(struct super_block *sb, unsigned long block)
565 {
566 	int offset = 0, files = 0, de_len;
567 	struct iso_directory_record *de;
568 	struct buffer_head *bh;
569 
570 	bh = sb_bread(sb, block);
571 	if (!bh)
572 		return true;
573 	while (files < 3) {
574 		de = (struct iso_directory_record *) (bh->b_data + offset);
575 		de_len = *(unsigned char *) de;
576 		if (de_len == 0)
577 			break;
578 		files++;
579 		offset += de_len;
580 	}
581 	brelse(bh);
582 	return files < 3;
583 }
584 
585 /*
586  * Initialize the superblock and read the root inode.
587  *
588  * Note: a check_disk_change() has been done immediately prior
589  * to this call, so we don't need to check again.
590  */
591 static int isofs_fill_super(struct super_block *s, void *data, int silent)
592 {
593 	struct buffer_head *bh = NULL, *pri_bh = NULL;
594 	struct hs_primary_descriptor *h_pri = NULL;
595 	struct iso_primary_descriptor *pri = NULL;
596 	struct iso_supplementary_descriptor *sec = NULL;
597 	struct iso_directory_record *rootp;
598 	struct inode *inode;
599 	struct iso9660_options opt;
600 	struct isofs_sb_info *sbi;
601 	unsigned long first_data_zone;
602 	int joliet_level = 0;
603 	int iso_blknum, block;
604 	int orig_zonesize;
605 	int table, error = -EINVAL;
606 	unsigned int vol_desc_start;
607 
608 	save_mount_options(s, data);
609 
610 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
611 	if (!sbi)
612 		return -ENOMEM;
613 	s->s_fs_info = sbi;
614 
615 	if (!parse_options((char *)data, &opt))
616 		goto out_freesbi;
617 
618 	/*
619 	 * First of all, get the hardware blocksize for this device.
620 	 * If we don't know what it is, or the hardware blocksize is
621 	 * larger than the blocksize the user specified, then use
622 	 * that value.
623 	 */
624 	/*
625 	 * What if bugger tells us to go beyond page size?
626 	 */
627 	opt.blocksize = sb_min_blocksize(s, opt.blocksize);
628 
629 	sbi->s_high_sierra = 0; /* default is iso9660 */
630 
631 	vol_desc_start = (opt.sbsector != -1) ?
632 		opt.sbsector : isofs_get_last_session(s,opt.session);
633 
634 	for (iso_blknum = vol_desc_start+16;
635 		iso_blknum < vol_desc_start+100; iso_blknum++) {
636 		struct hs_volume_descriptor *hdp;
637 		struct iso_volume_descriptor  *vdp;
638 
639 		block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
640 		if (!(bh = sb_bread(s, block)))
641 			goto out_no_read;
642 
643 		vdp = (struct iso_volume_descriptor *)bh->b_data;
644 		hdp = (struct hs_volume_descriptor *)bh->b_data;
645 
646 		/*
647 		 * Due to the overlapping physical location of the descriptors,
648 		 * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
649 		 * proper identification in this case, we first check for ISO.
650 		 */
651 		if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
652 			if (isonum_711(vdp->type) == ISO_VD_END)
653 				break;
654 			if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
655 				if (pri == NULL) {
656 					pri = (struct iso_primary_descriptor *)vdp;
657 					/* Save the buffer in case we need it ... */
658 					pri_bh = bh;
659 					bh = NULL;
660 				}
661 			}
662 #ifdef CONFIG_JOLIET
663 			else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
664 				sec = (struct iso_supplementary_descriptor *)vdp;
665 				if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
666 					if (opt.joliet) {
667 						if (sec->escape[2] == 0x40)
668 							joliet_level = 1;
669 						else if (sec->escape[2] == 0x43)
670 							joliet_level = 2;
671 						else if (sec->escape[2] == 0x45)
672 							joliet_level = 3;
673 
674 						printk(KERN_DEBUG "ISO 9660 Extensions: "
675 							"Microsoft Joliet Level %d\n",
676 							joliet_level);
677 					}
678 					goto root_found;
679 				} else {
680 				/* Unknown supplementary volume descriptor */
681 				sec = NULL;
682 				}
683 			}
684 #endif
685 		} else {
686 			if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
687 				if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
688 					goto out_freebh;
689 
690 				sbi->s_high_sierra = 1;
691 				opt.rock = 0;
692 				h_pri = (struct hs_primary_descriptor *)vdp;
693 				goto root_found;
694 			}
695 		}
696 
697 		/* Just skip any volume descriptors we don't recognize */
698 
699 		brelse(bh);
700 		bh = NULL;
701 	}
702 	/*
703 	 * If we fall through, either no volume descriptor was found,
704 	 * or else we passed a primary descriptor looking for others.
705 	 */
706 	if (!pri)
707 		goto out_unknown_format;
708 	brelse(bh);
709 	bh = pri_bh;
710 	pri_bh = NULL;
711 
712 root_found:
713 
714 	if (joliet_level && (pri == NULL || !opt.rock)) {
715 		/* This is the case of Joliet with the norock mount flag.
716 		 * A disc with both Joliet and Rock Ridge is handled later
717 		 */
718 		pri = (struct iso_primary_descriptor *) sec;
719 	}
720 
721 	if(sbi->s_high_sierra){
722 		rootp = (struct iso_directory_record *) h_pri->root_directory_record;
723 		sbi->s_nzones = isonum_733(h_pri->volume_space_size);
724 		sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
725 		sbi->s_max_size = isonum_733(h_pri->volume_space_size);
726 	} else {
727 		if (!pri)
728 			goto out_freebh;
729 		rootp = (struct iso_directory_record *) pri->root_directory_record;
730 		sbi->s_nzones = isonum_733(pri->volume_space_size);
731 		sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
732 		sbi->s_max_size = isonum_733(pri->volume_space_size);
733 	}
734 
735 	sbi->s_ninodes = 0; /* No way to figure this out easily */
736 
737 	orig_zonesize = sbi->s_log_zone_size;
738 	/*
739 	 * If the zone size is smaller than the hardware sector size,
740 	 * this is a fatal error.  This would occur if the disc drive
741 	 * had sectors that were 2048 bytes, but the filesystem had
742 	 * blocks that were 512 bytes (which should only very rarely
743 	 * happen.)
744 	 */
745 	if (orig_zonesize < opt.blocksize)
746 		goto out_bad_size;
747 
748 	/* RDE: convert log zone size to bit shift */
749 	switch (sbi->s_log_zone_size) {
750 	case  512: sbi->s_log_zone_size =  9; break;
751 	case 1024: sbi->s_log_zone_size = 10; break;
752 	case 2048: sbi->s_log_zone_size = 11; break;
753 
754 	default:
755 		goto out_bad_zone_size;
756 	}
757 
758 	s->s_magic = ISOFS_SUPER_MAGIC;
759 
760 	/*
761 	 * With multi-extent files, file size is only limited by the maximum
762 	 * size of a file system, which is 8 TB.
763 	 */
764 	s->s_maxbytes = 0x80000000000LL;
765 
766 	/* Set this for reference. Its not currently used except on write
767 	   which we don't have .. */
768 
769 	first_data_zone = isonum_733(rootp->extent) +
770 			  isonum_711(rootp->ext_attr_length);
771 	sbi->s_firstdatazone = first_data_zone;
772 #ifndef BEQUIET
773 	printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
774 		sbi->s_max_size, 1UL << sbi->s_log_zone_size);
775 	printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
776 	if(sbi->s_high_sierra)
777 		printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
778 #endif
779 
780 	/*
781 	 * If the Joliet level is set, we _may_ decide to use the
782 	 * secondary descriptor, but can't be sure until after we
783 	 * read the root inode. But before reading the root inode
784 	 * we may need to change the device blocksize, and would
785 	 * rather release the old buffer first. So, we cache the
786 	 * first_data_zone value from the secondary descriptor.
787 	 */
788 	if (joliet_level) {
789 		pri = (struct iso_primary_descriptor *) sec;
790 		rootp = (struct iso_directory_record *)
791 			pri->root_directory_record;
792 		first_data_zone = isonum_733(rootp->extent) +
793 				isonum_711(rootp->ext_attr_length);
794 	}
795 
796 	/*
797 	 * We're all done using the volume descriptor, and may need
798 	 * to change the device blocksize, so release the buffer now.
799 	 */
800 	brelse(pri_bh);
801 	brelse(bh);
802 
803 	/*
804 	 * Force the blocksize to 512 for 512 byte sectors.  The file
805 	 * read primitives really get it wrong in a bad way if we don't
806 	 * do this.
807 	 *
808 	 * Note - we should never be setting the blocksize to something
809 	 * less than the hardware sector size for the device.  If we
810 	 * do, we would end up having to read larger buffers and split
811 	 * out portions to satisfy requests.
812 	 *
813 	 * Note2- the idea here is that we want to deal with the optimal
814 	 * zonesize in the filesystem.  If we have it set to something less,
815 	 * then we have horrible problems with trying to piece together
816 	 * bits of adjacent blocks in order to properly read directory
817 	 * entries.  By forcing the blocksize in this way, we ensure
818 	 * that we will never be required to do this.
819 	 */
820 	sb_set_blocksize(s, orig_zonesize);
821 
822 	sbi->s_nls_iocharset = NULL;
823 
824 #ifdef CONFIG_JOLIET
825 	if (joliet_level && opt.utf8 == 0) {
826 		char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
827 		sbi->s_nls_iocharset = load_nls(p);
828 		if (! sbi->s_nls_iocharset) {
829 			/* Fail only if explicit charset specified */
830 			if (opt.iocharset)
831 				goto out_freesbi;
832 			sbi->s_nls_iocharset = load_nls_default();
833 		}
834 	}
835 #endif
836 	s->s_op = &isofs_sops;
837 	s->s_export_op = &isofs_export_ops;
838 	sbi->s_mapping = opt.map;
839 	sbi->s_rock = (opt.rock ? 2 : 0);
840 	sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
841 	sbi->s_cruft = opt.cruft;
842 	sbi->s_hide = opt.hide;
843 	sbi->s_showassoc = opt.showassoc;
844 	sbi->s_uid = opt.uid;
845 	sbi->s_gid = opt.gid;
846 	sbi->s_uid_set = opt.uid_set;
847 	sbi->s_gid_set = opt.gid_set;
848 	sbi->s_utf8 = opt.utf8;
849 	sbi->s_nocompress = opt.nocompress;
850 	sbi->s_overriderockperm = opt.overriderockperm;
851 	/*
852 	 * It would be incredibly stupid to allow people to mark every file
853 	 * on the disk as suid, so we merely allow them to set the default
854 	 * permissions.
855 	 */
856 	if (opt.fmode != ISOFS_INVALID_MODE)
857 		sbi->s_fmode = opt.fmode & 0777;
858 	else
859 		sbi->s_fmode = ISOFS_INVALID_MODE;
860 	if (opt.dmode != ISOFS_INVALID_MODE)
861 		sbi->s_dmode = opt.dmode & 0777;
862 	else
863 		sbi->s_dmode = ISOFS_INVALID_MODE;
864 
865 	/*
866 	 * Read the root inode, which _may_ result in changing
867 	 * the s_rock flag. Once we have the final s_rock value,
868 	 * we then decide whether to use the Joliet descriptor.
869 	 */
870 	inode = isofs_iget(s, sbi->s_firstdatazone, 0);
871 	if (IS_ERR(inode))
872 		goto out_no_root;
873 
874 	/*
875 	 * Fix for broken CDs with Rock Ridge and empty ISO root directory but
876 	 * correct Joliet root directory.
877 	 */
878 	if (sbi->s_rock == 1 && joliet_level &&
879 				rootdir_empty(s, sbi->s_firstdatazone)) {
880 		printk(KERN_NOTICE
881 			"ISOFS: primary root directory is empty. "
882 			"Disabling Rock Ridge and switching to Joliet.");
883 		sbi->s_rock = 0;
884 	}
885 
886 	/*
887 	 * If this disk has both Rock Ridge and Joliet on it, then we
888 	 * want to use Rock Ridge by default.  This can be overridden
889 	 * by using the norock mount option.  There is still one other
890 	 * possibility that is not taken into account: a Rock Ridge
891 	 * CD with Unicode names.  Until someone sees such a beast, it
892 	 * will not be supported.
893 	 */
894 	if (sbi->s_rock == 1) {
895 		joliet_level = 0;
896 	} else if (joliet_level) {
897 		sbi->s_rock = 0;
898 		if (sbi->s_firstdatazone != first_data_zone) {
899 			sbi->s_firstdatazone = first_data_zone;
900 			printk(KERN_DEBUG
901 				"ISOFS: changing to secondary root\n");
902 			iput(inode);
903 			inode = isofs_iget(s, sbi->s_firstdatazone, 0);
904 			if (IS_ERR(inode))
905 				goto out_no_root;
906 		}
907 	}
908 
909 	if (opt.check == 'u') {
910 		/* Only Joliet is case insensitive by default */
911 		if (joliet_level)
912 			opt.check = 'r';
913 		else
914 			opt.check = 's';
915 	}
916 	sbi->s_joliet_level = joliet_level;
917 
918 	/* Make sure the root inode is a directory */
919 	if (!S_ISDIR(inode->i_mode)) {
920 		printk(KERN_WARNING
921 			"isofs_fill_super: root inode is not a directory. "
922 			"Corrupted media?\n");
923 		goto out_iput;
924 	}
925 
926 	table = 0;
927 	if (joliet_level)
928 		table += 2;
929 	if (opt.check == 'r')
930 		table++;
931 
932 	s->s_d_op = &isofs_dentry_ops[table];
933 
934 	/* get the root dentry */
935 	s->s_root = d_make_root(inode);
936 	if (!(s->s_root)) {
937 		error = -ENOMEM;
938 		goto out_no_inode;
939 	}
940 
941 	kfree(opt.iocharset);
942 
943 	return 0;
944 
945 	/*
946 	 * Display error messages and free resources.
947 	 */
948 out_iput:
949 	iput(inode);
950 	goto out_no_inode;
951 out_no_root:
952 	error = PTR_ERR(inode);
953 	if (error != -ENOMEM)
954 		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
955 out_no_inode:
956 #ifdef CONFIG_JOLIET
957 	unload_nls(sbi->s_nls_iocharset);
958 #endif
959 	goto out_freesbi;
960 out_no_read:
961 	printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
962 		__func__, s->s_id, iso_blknum, block);
963 	goto out_freebh;
964 out_bad_zone_size:
965 	printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
966 		sbi->s_log_zone_size);
967 	goto out_freebh;
968 out_bad_size:
969 	printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
970 		orig_zonesize, opt.blocksize);
971 	goto out_freebh;
972 out_unknown_format:
973 	if (!silent)
974 		printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
975 
976 out_freebh:
977 	brelse(bh);
978 	brelse(pri_bh);
979 out_freesbi:
980 	kfree(opt.iocharset);
981 	kfree(sbi);
982 	s->s_fs_info = NULL;
983 	return error;
984 }
985 
986 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
987 {
988 	struct super_block *sb = dentry->d_sb;
989 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
990 
991 	buf->f_type = ISOFS_SUPER_MAGIC;
992 	buf->f_bsize = sb->s_blocksize;
993 	buf->f_blocks = (ISOFS_SB(sb)->s_nzones
994 		<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
995 	buf->f_bfree = 0;
996 	buf->f_bavail = 0;
997 	buf->f_files = ISOFS_SB(sb)->s_ninodes;
998 	buf->f_ffree = 0;
999 	buf->f_fsid.val[0] = (u32)id;
1000 	buf->f_fsid.val[1] = (u32)(id >> 32);
1001 	buf->f_namelen = NAME_MAX;
1002 	return 0;
1003 }
1004 
1005 /*
1006  * Get a set of blocks; filling in buffer_heads if already allocated
1007  * or getblk() if they are not.  Returns the number of blocks inserted
1008  * (-ve == error.)
1009  */
1010 int isofs_get_blocks(struct inode *inode, sector_t iblock,
1011 		     struct buffer_head **bh, unsigned long nblocks)
1012 {
1013 	unsigned long b_off = iblock;
1014 	unsigned offset, sect_size;
1015 	unsigned int firstext;
1016 	unsigned long nextblk, nextoff;
1017 	int section, rv, error;
1018 	struct iso_inode_info *ei = ISOFS_I(inode);
1019 
1020 	error = -EIO;
1021 	rv = 0;
1022 	if (iblock != b_off) {
1023 		printk(KERN_DEBUG "%s: block number too large\n", __func__);
1024 		goto abort;
1025 	}
1026 
1027 
1028 	offset = 0;
1029 	firstext = ei->i_first_extent;
1030 	sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1031 	nextblk = ei->i_next_section_block;
1032 	nextoff = ei->i_next_section_offset;
1033 	section = 0;
1034 
1035 	while (nblocks) {
1036 		/* If we are *way* beyond the end of the file, print a message.
1037 		 * Access beyond the end of the file up to the next page boundary
1038 		 * is normal, however because of the way the page cache works.
1039 		 * In this case, we just return 0 so that we can properly fill
1040 		 * the page with useless information without generating any
1041 		 * I/O errors.
1042 		 */
1043 		if (b_off > ((inode->i_size + PAGE_CACHE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1044 			printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1045 				__func__, b_off,
1046 				(unsigned long long)inode->i_size);
1047 			goto abort;
1048 		}
1049 
1050 		/* On the last section, nextblk == 0, section size is likely to
1051 		 * exceed sect_size by a partial block, and access beyond the
1052 		 * end of the file will reach beyond the section size, too.
1053 		 */
1054 		while (nextblk && (b_off >= (offset + sect_size))) {
1055 			struct inode *ninode;
1056 
1057 			offset += sect_size;
1058 			ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1059 			if (IS_ERR(ninode)) {
1060 				error = PTR_ERR(ninode);
1061 				goto abort;
1062 			}
1063 			firstext  = ISOFS_I(ninode)->i_first_extent;
1064 			sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1065 			nextblk   = ISOFS_I(ninode)->i_next_section_block;
1066 			nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1067 			iput(ninode);
1068 
1069 			if (++section > 100) {
1070 				printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1071 					" aborting...\n", __func__);
1072 				printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1073 					"nextblk=%lu nextoff=%lu\n", __func__,
1074 					b_off, firstext, (unsigned) sect_size,
1075 					nextblk, nextoff);
1076 				goto abort;
1077 			}
1078 		}
1079 
1080 		if (*bh) {
1081 			map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1082 		} else {
1083 			*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1084 			if (!*bh)
1085 				goto abort;
1086 		}
1087 		bh++;	/* Next buffer head */
1088 		b_off++;	/* Next buffer offset */
1089 		nblocks--;
1090 		rv++;
1091 	}
1092 
1093 	error = 0;
1094 abort:
1095 	return rv != 0 ? rv : error;
1096 }
1097 
1098 /*
1099  * Used by the standard interfaces.
1100  */
1101 static int isofs_get_block(struct inode *inode, sector_t iblock,
1102 		    struct buffer_head *bh_result, int create)
1103 {
1104 	int ret;
1105 
1106 	if (create) {
1107 		printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1108 		return -EROFS;
1109 	}
1110 
1111 	ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1112 	return ret < 0 ? ret : 0;
1113 }
1114 
1115 static int isofs_bmap(struct inode *inode, sector_t block)
1116 {
1117 	struct buffer_head dummy;
1118 	int error;
1119 
1120 	dummy.b_state = 0;
1121 	dummy.b_blocknr = -1000;
1122 	error = isofs_get_block(inode, block, &dummy, 0);
1123 	if (!error)
1124 		return dummy.b_blocknr;
1125 	return 0;
1126 }
1127 
1128 struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1129 {
1130 	sector_t blknr = isofs_bmap(inode, block);
1131 	if (!blknr)
1132 		return NULL;
1133 	return sb_bread(inode->i_sb, blknr);
1134 }
1135 
1136 static int isofs_readpage(struct file *file, struct page *page)
1137 {
1138 	return mpage_readpage(page, isofs_get_block);
1139 }
1140 
1141 static int isofs_readpages(struct file *file, struct address_space *mapping,
1142 			struct list_head *pages, unsigned nr_pages)
1143 {
1144 	return mpage_readpages(mapping, pages, nr_pages, isofs_get_block);
1145 }
1146 
1147 static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1148 {
1149 	return generic_block_bmap(mapping,block,isofs_get_block);
1150 }
1151 
1152 static const struct address_space_operations isofs_aops = {
1153 	.readpage = isofs_readpage,
1154 	.readpages = isofs_readpages,
1155 	.bmap = _isofs_bmap
1156 };
1157 
1158 static int isofs_read_level3_size(struct inode *inode)
1159 {
1160 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1161 	int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1162 	struct buffer_head *bh = NULL;
1163 	unsigned long block, offset, block_saved, offset_saved;
1164 	int i = 0;
1165 	int more_entries = 0;
1166 	struct iso_directory_record *tmpde = NULL;
1167 	struct iso_inode_info *ei = ISOFS_I(inode);
1168 
1169 	inode->i_size = 0;
1170 
1171 	/* The first 16 blocks are reserved as the System Area.  Thus,
1172 	 * no inodes can appear in block 0.  We use this to flag that
1173 	 * this is the last section. */
1174 	ei->i_next_section_block = 0;
1175 	ei->i_next_section_offset = 0;
1176 
1177 	block = ei->i_iget5_block;
1178 	offset = ei->i_iget5_offset;
1179 
1180 	do {
1181 		struct iso_directory_record *de;
1182 		unsigned int de_len;
1183 
1184 		if (!bh) {
1185 			bh = sb_bread(inode->i_sb, block);
1186 			if (!bh)
1187 				goto out_noread;
1188 		}
1189 		de = (struct iso_directory_record *) (bh->b_data + offset);
1190 		de_len = *(unsigned char *) de;
1191 
1192 		if (de_len == 0) {
1193 			brelse(bh);
1194 			bh = NULL;
1195 			++block;
1196 			offset = 0;
1197 			continue;
1198 		}
1199 
1200 		block_saved = block;
1201 		offset_saved = offset;
1202 		offset += de_len;
1203 
1204 		/* Make sure we have a full directory entry */
1205 		if (offset >= bufsize) {
1206 			int slop = bufsize - offset + de_len;
1207 			if (!tmpde) {
1208 				tmpde = kmalloc(256, GFP_KERNEL);
1209 				if (!tmpde)
1210 					goto out_nomem;
1211 			}
1212 			memcpy(tmpde, de, slop);
1213 			offset &= bufsize - 1;
1214 			block++;
1215 			brelse(bh);
1216 			bh = NULL;
1217 			if (offset) {
1218 				bh = sb_bread(inode->i_sb, block);
1219 				if (!bh)
1220 					goto out_noread;
1221 				memcpy((void *)tmpde+slop, bh->b_data, offset);
1222 			}
1223 			de = tmpde;
1224 		}
1225 
1226 		inode->i_size += isonum_733(de->size);
1227 		if (i == 1) {
1228 			ei->i_next_section_block = block_saved;
1229 			ei->i_next_section_offset = offset_saved;
1230 		}
1231 
1232 		more_entries = de->flags[-high_sierra] & 0x80;
1233 
1234 		i++;
1235 		if (i > 100)
1236 			goto out_toomany;
1237 	} while (more_entries);
1238 out:
1239 	kfree(tmpde);
1240 	if (bh)
1241 		brelse(bh);
1242 	return 0;
1243 
1244 out_nomem:
1245 	if (bh)
1246 		brelse(bh);
1247 	return -ENOMEM;
1248 
1249 out_noread:
1250 	printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1251 	kfree(tmpde);
1252 	return -EIO;
1253 
1254 out_toomany:
1255 	printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1256 		"isofs_read_level3_size: inode=%lu\n",
1257 		__func__, inode->i_ino);
1258 	goto out;
1259 }
1260 
1261 static int isofs_read_inode(struct inode *inode)
1262 {
1263 	struct super_block *sb = inode->i_sb;
1264 	struct isofs_sb_info *sbi = ISOFS_SB(sb);
1265 	unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1266 	unsigned long block;
1267 	int high_sierra = sbi->s_high_sierra;
1268 	struct buffer_head *bh = NULL;
1269 	struct iso_directory_record *de;
1270 	struct iso_directory_record *tmpde = NULL;
1271 	unsigned int de_len;
1272 	unsigned long offset;
1273 	struct iso_inode_info *ei = ISOFS_I(inode);
1274 	int ret = -EIO;
1275 
1276 	block = ei->i_iget5_block;
1277 	bh = sb_bread(inode->i_sb, block);
1278 	if (!bh)
1279 		goto out_badread;
1280 
1281 	offset = ei->i_iget5_offset;
1282 
1283 	de = (struct iso_directory_record *) (bh->b_data + offset);
1284 	de_len = *(unsigned char *) de;
1285 
1286 	if (offset + de_len > bufsize) {
1287 		int frag1 = bufsize - offset;
1288 
1289 		tmpde = kmalloc(de_len, GFP_KERNEL);
1290 		if (tmpde == NULL) {
1291 			printk(KERN_INFO "%s: out of memory\n", __func__);
1292 			ret = -ENOMEM;
1293 			goto fail;
1294 		}
1295 		memcpy(tmpde, bh->b_data + offset, frag1);
1296 		brelse(bh);
1297 		bh = sb_bread(inode->i_sb, ++block);
1298 		if (!bh)
1299 			goto out_badread;
1300 		memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1301 		de = tmpde;
1302 	}
1303 
1304 	inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1305 					ei->i_iget5_offset,
1306 					ISOFS_BUFFER_BITS(inode));
1307 
1308 	/* Assume it is a normal-format file unless told otherwise */
1309 	ei->i_file_format = isofs_file_normal;
1310 
1311 	if (de->flags[-high_sierra] & 2) {
1312 		if (sbi->s_dmode != ISOFS_INVALID_MODE)
1313 			inode->i_mode = S_IFDIR | sbi->s_dmode;
1314 		else
1315 			inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1316 		set_nlink(inode, 1);	/*
1317 					 * Set to 1.  We know there are 2, but
1318 					 * the find utility tries to optimize
1319 					 * if it is 2, and it screws up.  It is
1320 					 * easier to give 1 which tells find to
1321 					 * do it the hard way.
1322 					 */
1323 	} else {
1324 		if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1325 			inode->i_mode = S_IFREG | sbi->s_fmode;
1326 		} else {
1327 			/*
1328 			 * Set default permissions: r-x for all.  The disc
1329 			 * could be shared with DOS machines so virtually
1330 			 * anything could be a valid executable.
1331 			 */
1332 			inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1333 		}
1334 		set_nlink(inode, 1);
1335 	}
1336 	inode->i_uid = sbi->s_uid;
1337 	inode->i_gid = sbi->s_gid;
1338 	inode->i_blocks = 0;
1339 
1340 	ei->i_format_parm[0] = 0;
1341 	ei->i_format_parm[1] = 0;
1342 	ei->i_format_parm[2] = 0;
1343 
1344 	ei->i_section_size = isonum_733(de->size);
1345 	if (de->flags[-high_sierra] & 0x80) {
1346 		ret = isofs_read_level3_size(inode);
1347 		if (ret < 0)
1348 			goto fail;
1349 		ret = -EIO;
1350 	} else {
1351 		ei->i_next_section_block = 0;
1352 		ei->i_next_section_offset = 0;
1353 		inode->i_size = isonum_733(de->size);
1354 	}
1355 
1356 	/*
1357 	 * Some dipshit decided to store some other bit of information
1358 	 * in the high byte of the file length.  Truncate size in case
1359 	 * this CDROM was mounted with the cruft option.
1360 	 */
1361 
1362 	if (sbi->s_cruft)
1363 		inode->i_size &= 0x00ffffff;
1364 
1365 	if (de->interleave[0]) {
1366 		printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1367 		inode->i_size = 0;
1368 	}
1369 
1370 	/* I have no idea what file_unit_size is used for, so
1371 	   we will flag it for now */
1372 	if (de->file_unit_size[0] != 0) {
1373 		printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1374 			inode->i_ino);
1375 	}
1376 
1377 	/* I have no idea what other flag bits are used for, so
1378 	   we will flag it for now */
1379 #ifdef DEBUG
1380 	if((de->flags[-high_sierra] & ~2)!= 0){
1381 		printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1382 				"(%ld %x).\n",
1383 			inode->i_ino, de->flags[-high_sierra]);
1384 	}
1385 #endif
1386 
1387 	inode->i_mtime.tv_sec =
1388 	inode->i_atime.tv_sec =
1389 	inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
1390 	inode->i_mtime.tv_nsec =
1391 	inode->i_atime.tv_nsec =
1392 	inode->i_ctime.tv_nsec = 0;
1393 
1394 	ei->i_first_extent = (isonum_733(de->extent) +
1395 			isonum_711(de->ext_attr_length));
1396 
1397 	/* Set the number of blocks for stat() - should be done before RR */
1398 	inode->i_blocks = (inode->i_size + 511) >> 9;
1399 
1400 	/*
1401 	 * Now test for possible Rock Ridge extensions which will override
1402 	 * some of these numbers in the inode structure.
1403 	 */
1404 
1405 	if (!high_sierra) {
1406 		parse_rock_ridge_inode(de, inode);
1407 		/* if we want uid/gid set, override the rock ridge setting */
1408 		if (sbi->s_uid_set)
1409 			inode->i_uid = sbi->s_uid;
1410 		if (sbi->s_gid_set)
1411 			inode->i_gid = sbi->s_gid;
1412 	}
1413 	/* Now set final access rights if overriding rock ridge setting */
1414 	if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1415 	    sbi->s_dmode != ISOFS_INVALID_MODE)
1416 		inode->i_mode = S_IFDIR | sbi->s_dmode;
1417 	if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1418 	    sbi->s_fmode != ISOFS_INVALID_MODE)
1419 		inode->i_mode = S_IFREG | sbi->s_fmode;
1420 
1421 	/* Install the inode operations vector */
1422 	if (S_ISREG(inode->i_mode)) {
1423 		inode->i_fop = &generic_ro_fops;
1424 		switch (ei->i_file_format) {
1425 #ifdef CONFIG_ZISOFS
1426 		case isofs_file_compressed:
1427 			inode->i_data.a_ops = &zisofs_aops;
1428 			break;
1429 #endif
1430 		default:
1431 			inode->i_data.a_ops = &isofs_aops;
1432 			break;
1433 		}
1434 	} else if (S_ISDIR(inode->i_mode)) {
1435 		inode->i_op = &isofs_dir_inode_operations;
1436 		inode->i_fop = &isofs_dir_operations;
1437 	} else if (S_ISLNK(inode->i_mode)) {
1438 		inode->i_op = &page_symlink_inode_operations;
1439 		inode->i_data.a_ops = &isofs_symlink_aops;
1440 	} else
1441 		/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1442 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1443 
1444 	ret = 0;
1445 out:
1446 	kfree(tmpde);
1447 	if (bh)
1448 		brelse(bh);
1449 	return ret;
1450 
1451 out_badread:
1452 	printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1453 fail:
1454 	goto out;
1455 }
1456 
1457 struct isofs_iget5_callback_data {
1458 	unsigned long block;
1459 	unsigned long offset;
1460 };
1461 
1462 static int isofs_iget5_test(struct inode *ino, void *data)
1463 {
1464 	struct iso_inode_info *i = ISOFS_I(ino);
1465 	struct isofs_iget5_callback_data *d =
1466 		(struct isofs_iget5_callback_data*)data;
1467 	return (i->i_iget5_block == d->block)
1468 		&& (i->i_iget5_offset == d->offset);
1469 }
1470 
1471 static int isofs_iget5_set(struct inode *ino, void *data)
1472 {
1473 	struct iso_inode_info *i = ISOFS_I(ino);
1474 	struct isofs_iget5_callback_data *d =
1475 		(struct isofs_iget5_callback_data*)data;
1476 	i->i_iget5_block = d->block;
1477 	i->i_iget5_offset = d->offset;
1478 	return 0;
1479 }
1480 
1481 /* Store, in the inode's containing structure, the block and block
1482  * offset that point to the underlying meta-data for the inode.  The
1483  * code below is otherwise similar to the iget() code in
1484  * include/linux/fs.h */
1485 struct inode *isofs_iget(struct super_block *sb,
1486 			 unsigned long block,
1487 			 unsigned long offset)
1488 {
1489 	unsigned long hashval;
1490 	struct inode *inode;
1491 	struct isofs_iget5_callback_data data;
1492 	long ret;
1493 
1494 	if (offset >= 1ul << sb->s_blocksize_bits)
1495 		return ERR_PTR(-EINVAL);
1496 
1497 	data.block = block;
1498 	data.offset = offset;
1499 
1500 	hashval = (block << sb->s_blocksize_bits) | offset;
1501 
1502 	inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1503 				&isofs_iget5_set, &data);
1504 
1505 	if (!inode)
1506 		return ERR_PTR(-ENOMEM);
1507 
1508 	if (inode->i_state & I_NEW) {
1509 		ret = isofs_read_inode(inode);
1510 		if (ret < 0) {
1511 			iget_failed(inode);
1512 			inode = ERR_PTR(ret);
1513 		} else {
1514 			unlock_new_inode(inode);
1515 		}
1516 	}
1517 
1518 	return inode;
1519 }
1520 
1521 static struct dentry *isofs_mount(struct file_system_type *fs_type,
1522 	int flags, const char *dev_name, void *data)
1523 {
1524 	/* We don't support read-write mounts */
1525 	if (!(flags & MS_RDONLY))
1526 		return ERR_PTR(-EACCES);
1527 	return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1528 }
1529 
1530 static struct file_system_type iso9660_fs_type = {
1531 	.owner		= THIS_MODULE,
1532 	.name		= "iso9660",
1533 	.mount		= isofs_mount,
1534 	.kill_sb	= kill_block_super,
1535 	.fs_flags	= FS_REQUIRES_DEV,
1536 };
1537 MODULE_ALIAS_FS("iso9660");
1538 MODULE_ALIAS("iso9660");
1539 
1540 static int __init init_iso9660_fs(void)
1541 {
1542 	int err = init_inodecache();
1543 	if (err)
1544 		goto out;
1545 #ifdef CONFIG_ZISOFS
1546 	err = zisofs_init();
1547 	if (err)
1548 		goto out1;
1549 #endif
1550 	err = register_filesystem(&iso9660_fs_type);
1551 	if (err)
1552 		goto out2;
1553 	return 0;
1554 out2:
1555 #ifdef CONFIG_ZISOFS
1556 	zisofs_cleanup();
1557 out1:
1558 #endif
1559 	destroy_inodecache();
1560 out:
1561 	return err;
1562 }
1563 
1564 static void __exit exit_iso9660_fs(void)
1565 {
1566         unregister_filesystem(&iso9660_fs_type);
1567 #ifdef CONFIG_ZISOFS
1568 	zisofs_cleanup();
1569 #endif
1570 	destroy_inodecache();
1571 }
1572 
1573 module_init(init_iso9660_fs)
1574 module_exit(exit_iso9660_fs)
1575 MODULE_LICENSE("GPL");
1576