xref: /openbmc/linux/fs/hpfs/super.c (revision bc000245)
1 /*
2  *  linux/fs/hpfs/super.c
3  *
4  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
5  *
6  *  mounting, unmounting, error handling
7  */
8 
9 #include "hpfs_fn.h"
10 #include <linux/module.h>
11 #include <linux/parser.h>
12 #include <linux/init.h>
13 #include <linux/statfs.h>
14 #include <linux/magic.h>
15 #include <linux/sched.h>
16 #include <linux/bitmap.h>
17 #include <linux/slab.h>
18 
19 /* Mark the filesystem dirty, so that chkdsk checks it when os/2 booted */
20 
21 static void mark_dirty(struct super_block *s, int remount)
22 {
23 	if (hpfs_sb(s)->sb_chkdsk && (remount || !(s->s_flags & MS_RDONLY))) {
24 		struct buffer_head *bh;
25 		struct hpfs_spare_block *sb;
26 		if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
27 			sb->dirty = 1;
28 			sb->old_wrote = 0;
29 			mark_buffer_dirty(bh);
30 			sync_dirty_buffer(bh);
31 			brelse(bh);
32 		}
33 	}
34 }
35 
36 /* Mark the filesystem clean (mark it dirty for chkdsk if chkdsk==2 or if there
37    were errors) */
38 
39 static void unmark_dirty(struct super_block *s)
40 {
41 	struct buffer_head *bh;
42 	struct hpfs_spare_block *sb;
43 	if (s->s_flags & MS_RDONLY) return;
44 	sync_blockdev(s->s_bdev);
45 	if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
46 		sb->dirty = hpfs_sb(s)->sb_chkdsk > 1 - hpfs_sb(s)->sb_was_error;
47 		sb->old_wrote = hpfs_sb(s)->sb_chkdsk >= 2 && !hpfs_sb(s)->sb_was_error;
48 		mark_buffer_dirty(bh);
49 		sync_dirty_buffer(bh);
50 		brelse(bh);
51 	}
52 }
53 
54 /* Filesystem error... */
55 static char err_buf[1024];
56 
57 void hpfs_error(struct super_block *s, const char *fmt, ...)
58 {
59 	va_list args;
60 
61 	va_start(args, fmt);
62 	vsnprintf(err_buf, sizeof(err_buf), fmt, args);
63 	va_end(args);
64 
65 	printk("HPFS: filesystem error: %s", err_buf);
66 	if (!hpfs_sb(s)->sb_was_error) {
67 		if (hpfs_sb(s)->sb_err == 2) {
68 			printk("; crashing the system because you wanted it\n");
69 			mark_dirty(s, 0);
70 			panic("HPFS panic");
71 		} else if (hpfs_sb(s)->sb_err == 1) {
72 			if (s->s_flags & MS_RDONLY) printk("; already mounted read-only\n");
73 			else {
74 				printk("; remounting read-only\n");
75 				mark_dirty(s, 0);
76 				s->s_flags |= MS_RDONLY;
77 			}
78 		} else if (s->s_flags & MS_RDONLY) printk("; going on - but anything won't be destroyed because it's read-only\n");
79 		else printk("; corrupted filesystem mounted read/write - your computer will explode within 20 seconds ... but you wanted it so!\n");
80 	} else printk("\n");
81 	hpfs_sb(s)->sb_was_error = 1;
82 }
83 
84 /*
85  * A little trick to detect cycles in many hpfs structures and don't let the
86  * kernel crash on corrupted filesystem. When first called, set c2 to 0.
87  *
88  * BTW. chkdsk doesn't detect cycles correctly. When I had 2 lost directories
89  * nested each in other, chkdsk locked up happilly.
90  */
91 
92 int hpfs_stop_cycles(struct super_block *s, int key, int *c1, int *c2,
93 		char *msg)
94 {
95 	if (*c2 && *c1 == key) {
96 		hpfs_error(s, "cycle detected on key %08x in %s", key, msg);
97 		return 1;
98 	}
99 	(*c2)++;
100 	if (!((*c2 - 1) & *c2)) *c1 = key;
101 	return 0;
102 }
103 
104 static void free_sbi(struct hpfs_sb_info *sbi)
105 {
106 	kfree(sbi->sb_cp_table);
107 	kfree(sbi->sb_bmp_dir);
108 	kfree(sbi);
109 }
110 
111 static void lazy_free_sbi(struct rcu_head *rcu)
112 {
113 	free_sbi(container_of(rcu, struct hpfs_sb_info, rcu));
114 }
115 
116 static void hpfs_put_super(struct super_block *s)
117 {
118 	hpfs_lock(s);
119 	unmark_dirty(s);
120 	hpfs_unlock(s);
121 	call_rcu(&hpfs_sb(s)->rcu, lazy_free_sbi);
122 }
123 
124 unsigned hpfs_count_one_bitmap(struct super_block *s, secno secno)
125 {
126 	struct quad_buffer_head qbh;
127 	unsigned long *bits;
128 	unsigned count;
129 
130 	bits = hpfs_map_4sectors(s, secno, &qbh, 0);
131 	if (!bits)
132 		return 0;
133 	count = bitmap_weight(bits, 2048 * BITS_PER_BYTE);
134 	hpfs_brelse4(&qbh);
135 	return count;
136 }
137 
138 static unsigned count_bitmaps(struct super_block *s)
139 {
140 	unsigned n, count, n_bands;
141 	n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
142 	count = 0;
143 	for (n = 0; n < COUNT_RD_AHEAD; n++) {
144 		hpfs_prefetch_bitmap(s, n);
145 	}
146 	for (n = 0; n < n_bands; n++) {
147 		hpfs_prefetch_bitmap(s, n + COUNT_RD_AHEAD);
148 		count += hpfs_count_one_bitmap(s, le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[n]));
149 	}
150 	return count;
151 }
152 
153 static int hpfs_statfs(struct dentry *dentry, struct kstatfs *buf)
154 {
155 	struct super_block *s = dentry->d_sb;
156 	struct hpfs_sb_info *sbi = hpfs_sb(s);
157 	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
158 	hpfs_lock(s);
159 
160 	/*if (sbi->sb_n_free == -1) {*/
161 		sbi->sb_n_free = count_bitmaps(s);
162 		sbi->sb_n_free_dnodes = hpfs_count_one_bitmap(s, sbi->sb_dmap);
163 	/*}*/
164 	buf->f_type = s->s_magic;
165 	buf->f_bsize = 512;
166 	buf->f_blocks = sbi->sb_fs_size;
167 	buf->f_bfree = sbi->sb_n_free;
168 	buf->f_bavail = sbi->sb_n_free;
169 	buf->f_files = sbi->sb_dirband_size / 4;
170 	buf->f_ffree = sbi->sb_n_free_dnodes;
171 	buf->f_fsid.val[0] = (u32)id;
172 	buf->f_fsid.val[1] = (u32)(id >> 32);
173 	buf->f_namelen = 254;
174 
175 	hpfs_unlock(s);
176 
177 	return 0;
178 }
179 
180 static struct kmem_cache * hpfs_inode_cachep;
181 
182 static struct inode *hpfs_alloc_inode(struct super_block *sb)
183 {
184 	struct hpfs_inode_info *ei;
185 	ei = (struct hpfs_inode_info *)kmem_cache_alloc(hpfs_inode_cachep, GFP_NOFS);
186 	if (!ei)
187 		return NULL;
188 	ei->vfs_inode.i_version = 1;
189 	return &ei->vfs_inode;
190 }
191 
192 static void hpfs_i_callback(struct rcu_head *head)
193 {
194 	struct inode *inode = container_of(head, struct inode, i_rcu);
195 	kmem_cache_free(hpfs_inode_cachep, hpfs_i(inode));
196 }
197 
198 static void hpfs_destroy_inode(struct inode *inode)
199 {
200 	call_rcu(&inode->i_rcu, hpfs_i_callback);
201 }
202 
203 static void init_once(void *foo)
204 {
205 	struct hpfs_inode_info *ei = (struct hpfs_inode_info *) foo;
206 
207 	inode_init_once(&ei->vfs_inode);
208 }
209 
210 static int init_inodecache(void)
211 {
212 	hpfs_inode_cachep = kmem_cache_create("hpfs_inode_cache",
213 					     sizeof(struct hpfs_inode_info),
214 					     0, (SLAB_RECLAIM_ACCOUNT|
215 						SLAB_MEM_SPREAD),
216 					     init_once);
217 	if (hpfs_inode_cachep == NULL)
218 		return -ENOMEM;
219 	return 0;
220 }
221 
222 static void destroy_inodecache(void)
223 {
224 	/*
225 	 * Make sure all delayed rcu free inodes are flushed before we
226 	 * destroy cache.
227 	 */
228 	rcu_barrier();
229 	kmem_cache_destroy(hpfs_inode_cachep);
230 }
231 
232 /*
233  * A tiny parser for option strings, stolen from dosfs.
234  * Stolen again from read-only hpfs.
235  * And updated for table-driven option parsing.
236  */
237 
238 enum {
239 	Opt_help, Opt_uid, Opt_gid, Opt_umask, Opt_case_lower, Opt_case_asis,
240 	Opt_check_none, Opt_check_normal, Opt_check_strict,
241 	Opt_err_cont, Opt_err_ro, Opt_err_panic,
242 	Opt_eas_no, Opt_eas_ro, Opt_eas_rw,
243 	Opt_chkdsk_no, Opt_chkdsk_errors, Opt_chkdsk_always,
244 	Opt_timeshift, Opt_err,
245 };
246 
247 static const match_table_t tokens = {
248 	{Opt_help, "help"},
249 	{Opt_uid, "uid=%u"},
250 	{Opt_gid, "gid=%u"},
251 	{Opt_umask, "umask=%o"},
252 	{Opt_case_lower, "case=lower"},
253 	{Opt_case_asis, "case=asis"},
254 	{Opt_check_none, "check=none"},
255 	{Opt_check_normal, "check=normal"},
256 	{Opt_check_strict, "check=strict"},
257 	{Opt_err_cont, "errors=continue"},
258 	{Opt_err_ro, "errors=remount-ro"},
259 	{Opt_err_panic, "errors=panic"},
260 	{Opt_eas_no, "eas=no"},
261 	{Opt_eas_ro, "eas=ro"},
262 	{Opt_eas_rw, "eas=rw"},
263 	{Opt_chkdsk_no, "chkdsk=no"},
264 	{Opt_chkdsk_errors, "chkdsk=errors"},
265 	{Opt_chkdsk_always, "chkdsk=always"},
266 	{Opt_timeshift, "timeshift=%d"},
267 	{Opt_err, NULL},
268 };
269 
270 static int parse_opts(char *opts, kuid_t *uid, kgid_t *gid, umode_t *umask,
271 		      int *lowercase, int *eas, int *chk, int *errs,
272 		      int *chkdsk, int *timeshift)
273 {
274 	char *p;
275 	int option;
276 
277 	if (!opts)
278 		return 1;
279 
280 	/*printk("Parsing opts: '%s'\n",opts);*/
281 
282 	while ((p = strsep(&opts, ",")) != NULL) {
283 		substring_t args[MAX_OPT_ARGS];
284 		int token;
285 		if (!*p)
286 			continue;
287 
288 		token = match_token(p, tokens, args);
289 		switch (token) {
290 		case Opt_help:
291 			return 2;
292 		case Opt_uid:
293 			if (match_int(args, &option))
294 				return 0;
295 			*uid = make_kuid(current_user_ns(), option);
296 			if (!uid_valid(*uid))
297 				return 0;
298 			break;
299 		case Opt_gid:
300 			if (match_int(args, &option))
301 				return 0;
302 			*gid = make_kgid(current_user_ns(), option);
303 			if (!gid_valid(*gid))
304 				return 0;
305 			break;
306 		case Opt_umask:
307 			if (match_octal(args, &option))
308 				return 0;
309 			*umask = option;
310 			break;
311 		case Opt_case_lower:
312 			*lowercase = 1;
313 			break;
314 		case Opt_case_asis:
315 			*lowercase = 0;
316 			break;
317 		case Opt_check_none:
318 			*chk = 0;
319 			break;
320 		case Opt_check_normal:
321 			*chk = 1;
322 			break;
323 		case Opt_check_strict:
324 			*chk = 2;
325 			break;
326 		case Opt_err_cont:
327 			*errs = 0;
328 			break;
329 		case Opt_err_ro:
330 			*errs = 1;
331 			break;
332 		case Opt_err_panic:
333 			*errs = 2;
334 			break;
335 		case Opt_eas_no:
336 			*eas = 0;
337 			break;
338 		case Opt_eas_ro:
339 			*eas = 1;
340 			break;
341 		case Opt_eas_rw:
342 			*eas = 2;
343 			break;
344 		case Opt_chkdsk_no:
345 			*chkdsk = 0;
346 			break;
347 		case Opt_chkdsk_errors:
348 			*chkdsk = 1;
349 			break;
350 		case Opt_chkdsk_always:
351 			*chkdsk = 2;
352 			break;
353 		case Opt_timeshift:
354 		{
355 			int m = 1;
356 			char *rhs = args[0].from;
357 			if (!rhs || !*rhs)
358 				return 0;
359 			if (*rhs == '-') m = -1;
360 			if (*rhs == '+' || *rhs == '-') rhs++;
361 			*timeshift = simple_strtoul(rhs, &rhs, 0) * m;
362 			if (*rhs)
363 				return 0;
364 			break;
365 		}
366 		default:
367 			return 0;
368 		}
369 	}
370 	return 1;
371 }
372 
373 static inline void hpfs_help(void)
374 {
375 	printk("\n\
376 HPFS filesystem options:\n\
377       help              do not mount and display this text\n\
378       uid=xxx           set uid of files that don't have uid specified in eas\n\
379       gid=xxx           set gid of files that don't have gid specified in eas\n\
380       umask=xxx         set mode of files that don't have mode specified in eas\n\
381       case=lower        lowercase all files\n\
382       case=asis         do not lowercase files (default)\n\
383       check=none        no fs checks - kernel may crash on corrupted filesystem\n\
384       check=normal      do some checks - it should not crash (default)\n\
385       check=strict      do extra time-consuming checks, used for debugging\n\
386       errors=continue   continue on errors\n\
387       errors=remount-ro remount read-only if errors found (default)\n\
388       errors=panic      panic on errors\n\
389       chkdsk=no         do not mark fs for chkdsking even if there were errors\n\
390       chkdsk=errors     mark fs dirty if errors found (default)\n\
391       chkdsk=always     always mark fs dirty - used for debugging\n\
392       eas=no            ignore extended attributes\n\
393       eas=ro            read but do not write extended attributes\n\
394       eas=rw            r/w eas => enables chmod, chown, mknod, ln -s (default)\n\
395       timeshift=nnn	add nnn seconds to file times\n\
396 \n");
397 }
398 
399 static int hpfs_remount_fs(struct super_block *s, int *flags, char *data)
400 {
401 	kuid_t uid;
402 	kgid_t gid;
403 	umode_t umask;
404 	int lowercase, eas, chk, errs, chkdsk, timeshift;
405 	int o;
406 	struct hpfs_sb_info *sbi = hpfs_sb(s);
407 	char *new_opts = kstrdup(data, GFP_KERNEL);
408 
409 	*flags |= MS_NOATIME;
410 
411 	hpfs_lock(s);
412 	uid = sbi->sb_uid; gid = sbi->sb_gid;
413 	umask = 0777 & ~sbi->sb_mode;
414 	lowercase = sbi->sb_lowercase;
415 	eas = sbi->sb_eas; chk = sbi->sb_chk; chkdsk = sbi->sb_chkdsk;
416 	errs = sbi->sb_err; timeshift = sbi->sb_timeshift;
417 
418 	if (!(o = parse_opts(data, &uid, &gid, &umask, &lowercase,
419 	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
420 		printk("HPFS: bad mount options.\n");
421 		goto out_err;
422 	}
423 	if (o == 2) {
424 		hpfs_help();
425 		goto out_err;
426 	}
427 	if (timeshift != sbi->sb_timeshift) {
428 		printk("HPFS: timeshift can't be changed using remount.\n");
429 		goto out_err;
430 	}
431 
432 	unmark_dirty(s);
433 
434 	sbi->sb_uid = uid; sbi->sb_gid = gid;
435 	sbi->sb_mode = 0777 & ~umask;
436 	sbi->sb_lowercase = lowercase;
437 	sbi->sb_eas = eas; sbi->sb_chk = chk; sbi->sb_chkdsk = chkdsk;
438 	sbi->sb_err = errs; sbi->sb_timeshift = timeshift;
439 
440 	if (!(*flags & MS_RDONLY)) mark_dirty(s, 1);
441 
442 	replace_mount_options(s, new_opts);
443 
444 	hpfs_unlock(s);
445 	return 0;
446 
447 out_err:
448 	hpfs_unlock(s);
449 	kfree(new_opts);
450 	return -EINVAL;
451 }
452 
453 /* Super operations */
454 
455 static const struct super_operations hpfs_sops =
456 {
457 	.alloc_inode	= hpfs_alloc_inode,
458 	.destroy_inode	= hpfs_destroy_inode,
459 	.evict_inode	= hpfs_evict_inode,
460 	.put_super	= hpfs_put_super,
461 	.statfs		= hpfs_statfs,
462 	.remount_fs	= hpfs_remount_fs,
463 	.show_options	= generic_show_options,
464 };
465 
466 static int hpfs_fill_super(struct super_block *s, void *options, int silent)
467 {
468 	struct buffer_head *bh0, *bh1, *bh2;
469 	struct hpfs_boot_block *bootblock;
470 	struct hpfs_super_block *superblock;
471 	struct hpfs_spare_block *spareblock;
472 	struct hpfs_sb_info *sbi;
473 	struct inode *root;
474 
475 	kuid_t uid;
476 	kgid_t gid;
477 	umode_t umask;
478 	int lowercase, eas, chk, errs, chkdsk, timeshift;
479 
480 	dnode_secno root_dno;
481 	struct hpfs_dirent *de = NULL;
482 	struct quad_buffer_head qbh;
483 
484 	int o;
485 
486 	save_mount_options(s, options);
487 
488 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
489 	if (!sbi) {
490 		return -ENOMEM;
491 	}
492 	s->s_fs_info = sbi;
493 
494 	mutex_init(&sbi->hpfs_mutex);
495 	hpfs_lock(s);
496 
497 	uid = current_uid();
498 	gid = current_gid();
499 	umask = current_umask();
500 	lowercase = 0;
501 	eas = 2;
502 	chk = 1;
503 	errs = 1;
504 	chkdsk = 1;
505 	timeshift = 0;
506 
507 	if (!(o = parse_opts(options, &uid, &gid, &umask, &lowercase,
508 	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
509 		printk("HPFS: bad mount options.\n");
510 		goto bail0;
511 	}
512 	if (o==2) {
513 		hpfs_help();
514 		goto bail0;
515 	}
516 
517 	/*sbi->sb_mounting = 1;*/
518 	sb_set_blocksize(s, 512);
519 	sbi->sb_fs_size = -1;
520 	if (!(bootblock = hpfs_map_sector(s, 0, &bh0, 0))) goto bail1;
521 	if (!(superblock = hpfs_map_sector(s, 16, &bh1, 1))) goto bail2;
522 	if (!(spareblock = hpfs_map_sector(s, 17, &bh2, 0))) goto bail3;
523 
524 	/* Check magics */
525 	if (/*le16_to_cpu(bootblock->magic) != BB_MAGIC
526 	    ||*/ le32_to_cpu(superblock->magic) != SB_MAGIC
527 	    || le32_to_cpu(spareblock->magic) != SP_MAGIC) {
528 		if (!silent) printk("HPFS: Bad magic ... probably not HPFS\n");
529 		goto bail4;
530 	}
531 
532 	/* Check version */
533 	if (!(s->s_flags & MS_RDONLY) &&
534 	      superblock->funcversion != 2 && superblock->funcversion != 3) {
535 		printk("HPFS: Bad version %d,%d. Mount readonly to go around\n",
536 			(int)superblock->version, (int)superblock->funcversion);
537 		printk("HPFS: please try recent version of HPFS driver at http://artax.karlin.mff.cuni.cz/~mikulas/vyplody/hpfs/index-e.cgi and if it still can't understand this format, contact author - mikulas@artax.karlin.mff.cuni.cz\n");
538 		goto bail4;
539 	}
540 
541 	s->s_flags |= MS_NOATIME;
542 
543 	/* Fill superblock stuff */
544 	s->s_magic = HPFS_SUPER_MAGIC;
545 	s->s_op = &hpfs_sops;
546 	s->s_d_op = &hpfs_dentry_operations;
547 
548 	sbi->sb_root = le32_to_cpu(superblock->root);
549 	sbi->sb_fs_size = le32_to_cpu(superblock->n_sectors);
550 	sbi->sb_bitmaps = le32_to_cpu(superblock->bitmaps);
551 	sbi->sb_dirband_start = le32_to_cpu(superblock->dir_band_start);
552 	sbi->sb_dirband_size = le32_to_cpu(superblock->n_dir_band);
553 	sbi->sb_dmap = le32_to_cpu(superblock->dir_band_bitmap);
554 	sbi->sb_uid = uid;
555 	sbi->sb_gid = gid;
556 	sbi->sb_mode = 0777 & ~umask;
557 	sbi->sb_n_free = -1;
558 	sbi->sb_n_free_dnodes = -1;
559 	sbi->sb_lowercase = lowercase;
560 	sbi->sb_eas = eas;
561 	sbi->sb_chk = chk;
562 	sbi->sb_chkdsk = chkdsk;
563 	sbi->sb_err = errs;
564 	sbi->sb_timeshift = timeshift;
565 	sbi->sb_was_error = 0;
566 	sbi->sb_cp_table = NULL;
567 	sbi->sb_c_bitmap = -1;
568 	sbi->sb_max_fwd_alloc = 0xffffff;
569 
570 	if (sbi->sb_fs_size >= 0x80000000) {
571 		hpfs_error(s, "invalid size in superblock: %08x",
572 			(unsigned)sbi->sb_fs_size);
573 		goto bail4;
574 	}
575 
576 	/* Load bitmap directory */
577 	if (!(sbi->sb_bmp_dir = hpfs_load_bitmap_directory(s, le32_to_cpu(superblock->bitmaps))))
578 		goto bail4;
579 
580 	/* Check for general fs errors*/
581 	if (spareblock->dirty && !spareblock->old_wrote) {
582 		if (errs == 2) {
583 			printk("HPFS: Improperly stopped, not mounted\n");
584 			goto bail4;
585 		}
586 		hpfs_error(s, "improperly stopped");
587 	}
588 
589 	if (!(s->s_flags & MS_RDONLY)) {
590 		spareblock->dirty = 1;
591 		spareblock->old_wrote = 0;
592 		mark_buffer_dirty(bh2);
593 	}
594 
595 	if (spareblock->hotfixes_used || spareblock->n_spares_used) {
596 		if (errs >= 2) {
597 			printk("HPFS: Hotfixes not supported here, try chkdsk\n");
598 			mark_dirty(s, 0);
599 			goto bail4;
600 		}
601 		hpfs_error(s, "hotfixes not supported here, try chkdsk");
602 		if (errs == 0) printk("HPFS: Proceeding, but your filesystem will be probably corrupted by this driver...\n");
603 		else printk("HPFS: This driver may read bad files or crash when operating on disk with hotfixes.\n");
604 	}
605 	if (le32_to_cpu(spareblock->n_dnode_spares) != le32_to_cpu(spareblock->n_dnode_spares_free)) {
606 		if (errs >= 2) {
607 			printk("HPFS: Spare dnodes used, try chkdsk\n");
608 			mark_dirty(s, 0);
609 			goto bail4;
610 		}
611 		hpfs_error(s, "warning: spare dnodes used, try chkdsk");
612 		if (errs == 0) printk("HPFS: Proceeding, but your filesystem could be corrupted if you delete files or directories\n");
613 	}
614 	if (chk) {
615 		unsigned a;
616 		if (le32_to_cpu(superblock->dir_band_end) - le32_to_cpu(superblock->dir_band_start) + 1 != le32_to_cpu(superblock->n_dir_band) ||
617 		    le32_to_cpu(superblock->dir_band_end) < le32_to_cpu(superblock->dir_band_start) || le32_to_cpu(superblock->n_dir_band) > 0x4000) {
618 			hpfs_error(s, "dir band size mismatch: dir_band_start==%08x, dir_band_end==%08x, n_dir_band==%08x",
619 				le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->dir_band_end), le32_to_cpu(superblock->n_dir_band));
620 			goto bail4;
621 		}
622 		a = sbi->sb_dirband_size;
623 		sbi->sb_dirband_size = 0;
624 		if (hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->n_dir_band), "dir_band") ||
625 		    hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_bitmap), 4, "dir_band_bitmap") ||
626 		    hpfs_chk_sectors(s, le32_to_cpu(superblock->bitmaps), 4, "bitmaps")) {
627 			mark_dirty(s, 0);
628 			goto bail4;
629 		}
630 		sbi->sb_dirband_size = a;
631 	} else printk("HPFS: You really don't want any checks? You are crazy...\n");
632 
633 	/* Load code page table */
634 	if (le32_to_cpu(spareblock->n_code_pages))
635 		if (!(sbi->sb_cp_table = hpfs_load_code_page(s, le32_to_cpu(spareblock->code_page_dir))))
636 			printk("HPFS: Warning: code page support is disabled\n");
637 
638 	brelse(bh2);
639 	brelse(bh1);
640 	brelse(bh0);
641 
642 	root = iget_locked(s, sbi->sb_root);
643 	if (!root)
644 		goto bail0;
645 	hpfs_init_inode(root);
646 	hpfs_read_inode(root);
647 	unlock_new_inode(root);
648 	s->s_root = d_make_root(root);
649 	if (!s->s_root)
650 		goto bail0;
651 
652 	/*
653 	 * find the root directory's . pointer & finish filling in the inode
654 	 */
655 
656 	root_dno = hpfs_fnode_dno(s, sbi->sb_root);
657 	if (root_dno)
658 		de = map_dirent(root, root_dno, "\001\001", 2, NULL, &qbh);
659 	if (!de)
660 		hpfs_error(s, "unable to find root dir");
661 	else {
662 		root->i_atime.tv_sec = local_to_gmt(s, le32_to_cpu(de->read_date));
663 		root->i_atime.tv_nsec = 0;
664 		root->i_mtime.tv_sec = local_to_gmt(s, le32_to_cpu(de->write_date));
665 		root->i_mtime.tv_nsec = 0;
666 		root->i_ctime.tv_sec = local_to_gmt(s, le32_to_cpu(de->creation_date));
667 		root->i_ctime.tv_nsec = 0;
668 		hpfs_i(root)->i_ea_size = le32_to_cpu(de->ea_size);
669 		hpfs_i(root)->i_parent_dir = root->i_ino;
670 		if (root->i_size == -1)
671 			root->i_size = 2048;
672 		if (root->i_blocks == -1)
673 			root->i_blocks = 5;
674 		hpfs_brelse4(&qbh);
675 	}
676 	hpfs_unlock(s);
677 	return 0;
678 
679 bail4:	brelse(bh2);
680 bail3:	brelse(bh1);
681 bail2:	brelse(bh0);
682 bail1:
683 bail0:
684 	hpfs_unlock(s);
685 	free_sbi(sbi);
686 	return -EINVAL;
687 }
688 
689 static struct dentry *hpfs_mount(struct file_system_type *fs_type,
690 	int flags, const char *dev_name, void *data)
691 {
692 	return mount_bdev(fs_type, flags, dev_name, data, hpfs_fill_super);
693 }
694 
695 static struct file_system_type hpfs_fs_type = {
696 	.owner		= THIS_MODULE,
697 	.name		= "hpfs",
698 	.mount		= hpfs_mount,
699 	.kill_sb	= kill_block_super,
700 	.fs_flags	= FS_REQUIRES_DEV,
701 };
702 MODULE_ALIAS_FS("hpfs");
703 
704 static int __init init_hpfs_fs(void)
705 {
706 	int err = init_inodecache();
707 	if (err)
708 		goto out1;
709 	err = register_filesystem(&hpfs_fs_type);
710 	if (err)
711 		goto out;
712 	return 0;
713 out:
714 	destroy_inodecache();
715 out1:
716 	return err;
717 }
718 
719 static void __exit exit_hpfs_fs(void)
720 {
721 	unregister_filesystem(&hpfs_fs_type);
722 	destroy_inodecache();
723 }
724 
725 module_init(init_hpfs_fs)
726 module_exit(exit_hpfs_fs)
727 MODULE_LICENSE("GPL");
728