xref: /openbmc/linux/fs/hpfs/super.c (revision c819e2cf)
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 	pr_err("filesystem error: %s", err_buf);
66 	if (!hpfs_sb(s)->sb_was_error) {
67 		if (hpfs_sb(s)->sb_err == 2) {
68 			pr_cont("; 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)
73 				pr_cont("; already mounted read-only\n");
74 			else {
75 				pr_cont("; remounting read-only\n");
76 				mark_dirty(s, 0);
77 				s->s_flags |= MS_RDONLY;
78 			}
79 		} else if (s->s_flags & MS_RDONLY)
80 				pr_cont("; going on - but anything won't be destroyed because it's read-only\n");
81 		else
82 			pr_cont("; corrupted filesystem mounted read/write - your computer will explode within 20 seconds ... but you wanted it so!\n");
83 	} else
84 		pr_cont("\n");
85 	hpfs_sb(s)->sb_was_error = 1;
86 }
87 
88 /*
89  * A little trick to detect cycles in many hpfs structures and don't let the
90  * kernel crash on corrupted filesystem. When first called, set c2 to 0.
91  *
92  * BTW. chkdsk doesn't detect cycles correctly. When I had 2 lost directories
93  * nested each in other, chkdsk locked up happilly.
94  */
95 
96 int hpfs_stop_cycles(struct super_block *s, int key, int *c1, int *c2,
97 		char *msg)
98 {
99 	if (*c2 && *c1 == key) {
100 		hpfs_error(s, "cycle detected on key %08x in %s", key, msg);
101 		return 1;
102 	}
103 	(*c2)++;
104 	if (!((*c2 - 1) & *c2)) *c1 = key;
105 	return 0;
106 }
107 
108 static void free_sbi(struct hpfs_sb_info *sbi)
109 {
110 	kfree(sbi->sb_cp_table);
111 	kfree(sbi->sb_bmp_dir);
112 	kfree(sbi);
113 }
114 
115 static void lazy_free_sbi(struct rcu_head *rcu)
116 {
117 	free_sbi(container_of(rcu, struct hpfs_sb_info, rcu));
118 }
119 
120 static void hpfs_put_super(struct super_block *s)
121 {
122 	hpfs_lock(s);
123 	unmark_dirty(s);
124 	hpfs_unlock(s);
125 	call_rcu(&hpfs_sb(s)->rcu, lazy_free_sbi);
126 }
127 
128 static unsigned hpfs_count_one_bitmap(struct super_block *s, secno secno)
129 {
130 	struct quad_buffer_head qbh;
131 	unsigned long *bits;
132 	unsigned count;
133 
134 	bits = hpfs_map_4sectors(s, secno, &qbh, 0);
135 	if (!bits)
136 		return (unsigned)-1;
137 	count = bitmap_weight(bits, 2048 * BITS_PER_BYTE);
138 	hpfs_brelse4(&qbh);
139 	return count;
140 }
141 
142 static unsigned count_bitmaps(struct super_block *s)
143 {
144 	unsigned n, count, n_bands;
145 	n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
146 	count = 0;
147 	for (n = 0; n < COUNT_RD_AHEAD; n++) {
148 		hpfs_prefetch_bitmap(s, n);
149 	}
150 	for (n = 0; n < n_bands; n++) {
151 		unsigned c;
152 		hpfs_prefetch_bitmap(s, n + COUNT_RD_AHEAD);
153 		c = hpfs_count_one_bitmap(s, le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[n]));
154 		if (c != (unsigned)-1)
155 			count += c;
156 	}
157 	return count;
158 }
159 
160 unsigned hpfs_get_free_dnodes(struct super_block *s)
161 {
162 	struct hpfs_sb_info *sbi = hpfs_sb(s);
163 	if (sbi->sb_n_free_dnodes == (unsigned)-1) {
164 		unsigned c = hpfs_count_one_bitmap(s, sbi->sb_dmap);
165 		if (c == (unsigned)-1)
166 			return 0;
167 		sbi->sb_n_free_dnodes = c;
168 	}
169 	return sbi->sb_n_free_dnodes;
170 }
171 
172 static int hpfs_statfs(struct dentry *dentry, struct kstatfs *buf)
173 {
174 	struct super_block *s = dentry->d_sb;
175 	struct hpfs_sb_info *sbi = hpfs_sb(s);
176 	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
177 
178 	hpfs_lock(s);
179 
180 	if (sbi->sb_n_free == (unsigned)-1)
181 		sbi->sb_n_free = count_bitmaps(s);
182 
183 	buf->f_type = s->s_magic;
184 	buf->f_bsize = 512;
185 	buf->f_blocks = sbi->sb_fs_size;
186 	buf->f_bfree = sbi->sb_n_free;
187 	buf->f_bavail = sbi->sb_n_free;
188 	buf->f_files = sbi->sb_dirband_size / 4;
189 	buf->f_ffree = hpfs_get_free_dnodes(s);
190 	buf->f_fsid.val[0] = (u32)id;
191 	buf->f_fsid.val[1] = (u32)(id >> 32);
192 	buf->f_namelen = 254;
193 
194 	hpfs_unlock(s);
195 
196 	return 0;
197 }
198 
199 static struct kmem_cache * hpfs_inode_cachep;
200 
201 static struct inode *hpfs_alloc_inode(struct super_block *sb)
202 {
203 	struct hpfs_inode_info *ei;
204 	ei = (struct hpfs_inode_info *)kmem_cache_alloc(hpfs_inode_cachep, GFP_NOFS);
205 	if (!ei)
206 		return NULL;
207 	ei->vfs_inode.i_version = 1;
208 	return &ei->vfs_inode;
209 }
210 
211 static void hpfs_i_callback(struct rcu_head *head)
212 {
213 	struct inode *inode = container_of(head, struct inode, i_rcu);
214 	kmem_cache_free(hpfs_inode_cachep, hpfs_i(inode));
215 }
216 
217 static void hpfs_destroy_inode(struct inode *inode)
218 {
219 	call_rcu(&inode->i_rcu, hpfs_i_callback);
220 }
221 
222 static void init_once(void *foo)
223 {
224 	struct hpfs_inode_info *ei = (struct hpfs_inode_info *) foo;
225 
226 	inode_init_once(&ei->vfs_inode);
227 }
228 
229 static int init_inodecache(void)
230 {
231 	hpfs_inode_cachep = kmem_cache_create("hpfs_inode_cache",
232 					     sizeof(struct hpfs_inode_info),
233 					     0, (SLAB_RECLAIM_ACCOUNT|
234 						SLAB_MEM_SPREAD),
235 					     init_once);
236 	if (hpfs_inode_cachep == NULL)
237 		return -ENOMEM;
238 	return 0;
239 }
240 
241 static void destroy_inodecache(void)
242 {
243 	/*
244 	 * Make sure all delayed rcu free inodes are flushed before we
245 	 * destroy cache.
246 	 */
247 	rcu_barrier();
248 	kmem_cache_destroy(hpfs_inode_cachep);
249 }
250 
251 /*
252  * A tiny parser for option strings, stolen from dosfs.
253  * Stolen again from read-only hpfs.
254  * And updated for table-driven option parsing.
255  */
256 
257 enum {
258 	Opt_help, Opt_uid, Opt_gid, Opt_umask, Opt_case_lower, Opt_case_asis,
259 	Opt_check_none, Opt_check_normal, Opt_check_strict,
260 	Opt_err_cont, Opt_err_ro, Opt_err_panic,
261 	Opt_eas_no, Opt_eas_ro, Opt_eas_rw,
262 	Opt_chkdsk_no, Opt_chkdsk_errors, Opt_chkdsk_always,
263 	Opt_timeshift, Opt_err,
264 };
265 
266 static const match_table_t tokens = {
267 	{Opt_help, "help"},
268 	{Opt_uid, "uid=%u"},
269 	{Opt_gid, "gid=%u"},
270 	{Opt_umask, "umask=%o"},
271 	{Opt_case_lower, "case=lower"},
272 	{Opt_case_asis, "case=asis"},
273 	{Opt_check_none, "check=none"},
274 	{Opt_check_normal, "check=normal"},
275 	{Opt_check_strict, "check=strict"},
276 	{Opt_err_cont, "errors=continue"},
277 	{Opt_err_ro, "errors=remount-ro"},
278 	{Opt_err_panic, "errors=panic"},
279 	{Opt_eas_no, "eas=no"},
280 	{Opt_eas_ro, "eas=ro"},
281 	{Opt_eas_rw, "eas=rw"},
282 	{Opt_chkdsk_no, "chkdsk=no"},
283 	{Opt_chkdsk_errors, "chkdsk=errors"},
284 	{Opt_chkdsk_always, "chkdsk=always"},
285 	{Opt_timeshift, "timeshift=%d"},
286 	{Opt_err, NULL},
287 };
288 
289 static int parse_opts(char *opts, kuid_t *uid, kgid_t *gid, umode_t *umask,
290 		      int *lowercase, int *eas, int *chk, int *errs,
291 		      int *chkdsk, int *timeshift)
292 {
293 	char *p;
294 	int option;
295 
296 	if (!opts)
297 		return 1;
298 
299 	/*pr_info("Parsing opts: '%s'\n",opts);*/
300 
301 	while ((p = strsep(&opts, ",")) != NULL) {
302 		substring_t args[MAX_OPT_ARGS];
303 		int token;
304 		if (!*p)
305 			continue;
306 
307 		token = match_token(p, tokens, args);
308 		switch (token) {
309 		case Opt_help:
310 			return 2;
311 		case Opt_uid:
312 			if (match_int(args, &option))
313 				return 0;
314 			*uid = make_kuid(current_user_ns(), option);
315 			if (!uid_valid(*uid))
316 				return 0;
317 			break;
318 		case Opt_gid:
319 			if (match_int(args, &option))
320 				return 0;
321 			*gid = make_kgid(current_user_ns(), option);
322 			if (!gid_valid(*gid))
323 				return 0;
324 			break;
325 		case Opt_umask:
326 			if (match_octal(args, &option))
327 				return 0;
328 			*umask = option;
329 			break;
330 		case Opt_case_lower:
331 			*lowercase = 1;
332 			break;
333 		case Opt_case_asis:
334 			*lowercase = 0;
335 			break;
336 		case Opt_check_none:
337 			*chk = 0;
338 			break;
339 		case Opt_check_normal:
340 			*chk = 1;
341 			break;
342 		case Opt_check_strict:
343 			*chk = 2;
344 			break;
345 		case Opt_err_cont:
346 			*errs = 0;
347 			break;
348 		case Opt_err_ro:
349 			*errs = 1;
350 			break;
351 		case Opt_err_panic:
352 			*errs = 2;
353 			break;
354 		case Opt_eas_no:
355 			*eas = 0;
356 			break;
357 		case Opt_eas_ro:
358 			*eas = 1;
359 			break;
360 		case Opt_eas_rw:
361 			*eas = 2;
362 			break;
363 		case Opt_chkdsk_no:
364 			*chkdsk = 0;
365 			break;
366 		case Opt_chkdsk_errors:
367 			*chkdsk = 1;
368 			break;
369 		case Opt_chkdsk_always:
370 			*chkdsk = 2;
371 			break;
372 		case Opt_timeshift:
373 		{
374 			int m = 1;
375 			char *rhs = args[0].from;
376 			if (!rhs || !*rhs)
377 				return 0;
378 			if (*rhs == '-') m = -1;
379 			if (*rhs == '+' || *rhs == '-') rhs++;
380 			*timeshift = simple_strtoul(rhs, &rhs, 0) * m;
381 			if (*rhs)
382 				return 0;
383 			break;
384 		}
385 		default:
386 			return 0;
387 		}
388 	}
389 	return 1;
390 }
391 
392 static inline void hpfs_help(void)
393 {
394 	pr_info("\n\
395 HPFS filesystem options:\n\
396       help              do not mount and display this text\n\
397       uid=xxx           set uid of files that don't have uid specified in eas\n\
398       gid=xxx           set gid of files that don't have gid specified in eas\n\
399       umask=xxx         set mode of files that don't have mode specified in eas\n\
400       case=lower        lowercase all files\n\
401       case=asis         do not lowercase files (default)\n\
402       check=none        no fs checks - kernel may crash on corrupted filesystem\n\
403       check=normal      do some checks - it should not crash (default)\n\
404       check=strict      do extra time-consuming checks, used for debugging\n\
405       errors=continue   continue on errors\n\
406       errors=remount-ro remount read-only if errors found (default)\n\
407       errors=panic      panic on errors\n\
408       chkdsk=no         do not mark fs for chkdsking even if there were errors\n\
409       chkdsk=errors     mark fs dirty if errors found (default)\n\
410       chkdsk=always     always mark fs dirty - used for debugging\n\
411       eas=no            ignore extended attributes\n\
412       eas=ro            read but do not write extended attributes\n\
413       eas=rw            r/w eas => enables chmod, chown, mknod, ln -s (default)\n\
414       timeshift=nnn	add nnn seconds to file times\n\
415 \n");
416 }
417 
418 static int hpfs_remount_fs(struct super_block *s, int *flags, char *data)
419 {
420 	kuid_t uid;
421 	kgid_t gid;
422 	umode_t umask;
423 	int lowercase, eas, chk, errs, chkdsk, timeshift;
424 	int o;
425 	struct hpfs_sb_info *sbi = hpfs_sb(s);
426 	char *new_opts = kstrdup(data, GFP_KERNEL);
427 
428 	sync_filesystem(s);
429 
430 	*flags |= MS_NOATIME;
431 
432 	hpfs_lock(s);
433 	uid = sbi->sb_uid; gid = sbi->sb_gid;
434 	umask = 0777 & ~sbi->sb_mode;
435 	lowercase = sbi->sb_lowercase;
436 	eas = sbi->sb_eas; chk = sbi->sb_chk; chkdsk = sbi->sb_chkdsk;
437 	errs = sbi->sb_err; timeshift = sbi->sb_timeshift;
438 
439 	if (!(o = parse_opts(data, &uid, &gid, &umask, &lowercase,
440 	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
441 		pr_err("bad mount options.\n");
442 		goto out_err;
443 	}
444 	if (o == 2) {
445 		hpfs_help();
446 		goto out_err;
447 	}
448 	if (timeshift != sbi->sb_timeshift) {
449 		pr_err("timeshift can't be changed using remount.\n");
450 		goto out_err;
451 	}
452 
453 	unmark_dirty(s);
454 
455 	sbi->sb_uid = uid; sbi->sb_gid = gid;
456 	sbi->sb_mode = 0777 & ~umask;
457 	sbi->sb_lowercase = lowercase;
458 	sbi->sb_eas = eas; sbi->sb_chk = chk; sbi->sb_chkdsk = chkdsk;
459 	sbi->sb_err = errs; sbi->sb_timeshift = timeshift;
460 
461 	if (!(*flags & MS_RDONLY)) mark_dirty(s, 1);
462 
463 	replace_mount_options(s, new_opts);
464 
465 	hpfs_unlock(s);
466 	return 0;
467 
468 out_err:
469 	hpfs_unlock(s);
470 	kfree(new_opts);
471 	return -EINVAL;
472 }
473 
474 /* Super operations */
475 
476 static const struct super_operations hpfs_sops =
477 {
478 	.alloc_inode	= hpfs_alloc_inode,
479 	.destroy_inode	= hpfs_destroy_inode,
480 	.evict_inode	= hpfs_evict_inode,
481 	.put_super	= hpfs_put_super,
482 	.statfs		= hpfs_statfs,
483 	.remount_fs	= hpfs_remount_fs,
484 	.show_options	= generic_show_options,
485 };
486 
487 static int hpfs_fill_super(struct super_block *s, void *options, int silent)
488 {
489 	struct buffer_head *bh0, *bh1, *bh2;
490 	struct hpfs_boot_block *bootblock;
491 	struct hpfs_super_block *superblock;
492 	struct hpfs_spare_block *spareblock;
493 	struct hpfs_sb_info *sbi;
494 	struct inode *root;
495 
496 	kuid_t uid;
497 	kgid_t gid;
498 	umode_t umask;
499 	int lowercase, eas, chk, errs, chkdsk, timeshift;
500 
501 	dnode_secno root_dno;
502 	struct hpfs_dirent *de = NULL;
503 	struct quad_buffer_head qbh;
504 
505 	int o;
506 
507 	save_mount_options(s, options);
508 
509 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
510 	if (!sbi) {
511 		return -ENOMEM;
512 	}
513 	s->s_fs_info = sbi;
514 
515 	mutex_init(&sbi->hpfs_mutex);
516 	hpfs_lock(s);
517 
518 	uid = current_uid();
519 	gid = current_gid();
520 	umask = current_umask();
521 	lowercase = 0;
522 	eas = 2;
523 	chk = 1;
524 	errs = 1;
525 	chkdsk = 1;
526 	timeshift = 0;
527 
528 	if (!(o = parse_opts(options, &uid, &gid, &umask, &lowercase,
529 	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
530 		pr_err("bad mount options.\n");
531 		goto bail0;
532 	}
533 	if (o==2) {
534 		hpfs_help();
535 		goto bail0;
536 	}
537 
538 	/*sbi->sb_mounting = 1;*/
539 	sb_set_blocksize(s, 512);
540 	sbi->sb_fs_size = -1;
541 	if (!(bootblock = hpfs_map_sector(s, 0, &bh0, 0))) goto bail1;
542 	if (!(superblock = hpfs_map_sector(s, 16, &bh1, 1))) goto bail2;
543 	if (!(spareblock = hpfs_map_sector(s, 17, &bh2, 0))) goto bail3;
544 
545 	/* Check magics */
546 	if (/*le16_to_cpu(bootblock->magic) != BB_MAGIC
547 	    ||*/ le32_to_cpu(superblock->magic) != SB_MAGIC
548 	    || le32_to_cpu(spareblock->magic) != SP_MAGIC) {
549 		if (!silent)
550 			pr_err("Bad magic ... probably not HPFS\n");
551 		goto bail4;
552 	}
553 
554 	/* Check version */
555 	if (!(s->s_flags & MS_RDONLY) &&
556 	      superblock->funcversion != 2 && superblock->funcversion != 3) {
557 		pr_err("Bad version %d,%d. Mount readonly to go around\n",
558 			(int)superblock->version, (int)superblock->funcversion);
559 		pr_err("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");
560 		goto bail4;
561 	}
562 
563 	s->s_flags |= MS_NOATIME;
564 
565 	/* Fill superblock stuff */
566 	s->s_magic = HPFS_SUPER_MAGIC;
567 	s->s_op = &hpfs_sops;
568 	s->s_d_op = &hpfs_dentry_operations;
569 
570 	sbi->sb_root = le32_to_cpu(superblock->root);
571 	sbi->sb_fs_size = le32_to_cpu(superblock->n_sectors);
572 	sbi->sb_bitmaps = le32_to_cpu(superblock->bitmaps);
573 	sbi->sb_dirband_start = le32_to_cpu(superblock->dir_band_start);
574 	sbi->sb_dirband_size = le32_to_cpu(superblock->n_dir_band);
575 	sbi->sb_dmap = le32_to_cpu(superblock->dir_band_bitmap);
576 	sbi->sb_uid = uid;
577 	sbi->sb_gid = gid;
578 	sbi->sb_mode = 0777 & ~umask;
579 	sbi->sb_n_free = -1;
580 	sbi->sb_n_free_dnodes = -1;
581 	sbi->sb_lowercase = lowercase;
582 	sbi->sb_eas = eas;
583 	sbi->sb_chk = chk;
584 	sbi->sb_chkdsk = chkdsk;
585 	sbi->sb_err = errs;
586 	sbi->sb_timeshift = timeshift;
587 	sbi->sb_was_error = 0;
588 	sbi->sb_cp_table = NULL;
589 	sbi->sb_c_bitmap = -1;
590 	sbi->sb_max_fwd_alloc = 0xffffff;
591 
592 	if (sbi->sb_fs_size >= 0x80000000) {
593 		hpfs_error(s, "invalid size in superblock: %08x",
594 			(unsigned)sbi->sb_fs_size);
595 		goto bail4;
596 	}
597 
598 	/* Load bitmap directory */
599 	if (!(sbi->sb_bmp_dir = hpfs_load_bitmap_directory(s, le32_to_cpu(superblock->bitmaps))))
600 		goto bail4;
601 
602 	/* Check for general fs errors*/
603 	if (spareblock->dirty && !spareblock->old_wrote) {
604 		if (errs == 2) {
605 			pr_err("Improperly stopped, not mounted\n");
606 			goto bail4;
607 		}
608 		hpfs_error(s, "improperly stopped");
609 	}
610 
611 	if (!(s->s_flags & MS_RDONLY)) {
612 		spareblock->dirty = 1;
613 		spareblock->old_wrote = 0;
614 		mark_buffer_dirty(bh2);
615 	}
616 
617 	if (spareblock->hotfixes_used || spareblock->n_spares_used) {
618 		if (errs >= 2) {
619 			pr_err("Hotfixes not supported here, try chkdsk\n");
620 			mark_dirty(s, 0);
621 			goto bail4;
622 		}
623 		hpfs_error(s, "hotfixes not supported here, try chkdsk");
624 		if (errs == 0)
625 			pr_err("Proceeding, but your filesystem will be probably corrupted by this driver...\n");
626 		else
627 			pr_err("This driver may read bad files or crash when operating on disk with hotfixes.\n");
628 	}
629 	if (le32_to_cpu(spareblock->n_dnode_spares) != le32_to_cpu(spareblock->n_dnode_spares_free)) {
630 		if (errs >= 2) {
631 			pr_err("Spare dnodes used, try chkdsk\n");
632 			mark_dirty(s, 0);
633 			goto bail4;
634 		}
635 		hpfs_error(s, "warning: spare dnodes used, try chkdsk");
636 		if (errs == 0)
637 			pr_err("Proceeding, but your filesystem could be corrupted if you delete files or directories\n");
638 	}
639 	if (chk) {
640 		unsigned a;
641 		if (le32_to_cpu(superblock->dir_band_end) - le32_to_cpu(superblock->dir_band_start) + 1 != le32_to_cpu(superblock->n_dir_band) ||
642 		    le32_to_cpu(superblock->dir_band_end) < le32_to_cpu(superblock->dir_band_start) || le32_to_cpu(superblock->n_dir_band) > 0x4000) {
643 			hpfs_error(s, "dir band size mismatch: dir_band_start==%08x, dir_band_end==%08x, n_dir_band==%08x",
644 				le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->dir_band_end), le32_to_cpu(superblock->n_dir_band));
645 			goto bail4;
646 		}
647 		a = sbi->sb_dirband_size;
648 		sbi->sb_dirband_size = 0;
649 		if (hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->n_dir_band), "dir_band") ||
650 		    hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_bitmap), 4, "dir_band_bitmap") ||
651 		    hpfs_chk_sectors(s, le32_to_cpu(superblock->bitmaps), 4, "bitmaps")) {
652 			mark_dirty(s, 0);
653 			goto bail4;
654 		}
655 		sbi->sb_dirband_size = a;
656 	} else
657 		pr_err("You really don't want any checks? You are crazy...\n");
658 
659 	/* Load code page table */
660 	if (le32_to_cpu(spareblock->n_code_pages))
661 		if (!(sbi->sb_cp_table = hpfs_load_code_page(s, le32_to_cpu(spareblock->code_page_dir))))
662 			pr_err("code page support is disabled\n");
663 
664 	brelse(bh2);
665 	brelse(bh1);
666 	brelse(bh0);
667 
668 	root = iget_locked(s, sbi->sb_root);
669 	if (!root)
670 		goto bail0;
671 	hpfs_init_inode(root);
672 	hpfs_read_inode(root);
673 	unlock_new_inode(root);
674 	s->s_root = d_make_root(root);
675 	if (!s->s_root)
676 		goto bail0;
677 
678 	/*
679 	 * find the root directory's . pointer & finish filling in the inode
680 	 */
681 
682 	root_dno = hpfs_fnode_dno(s, sbi->sb_root);
683 	if (root_dno)
684 		de = map_dirent(root, root_dno, "\001\001", 2, NULL, &qbh);
685 	if (!de)
686 		hpfs_error(s, "unable to find root dir");
687 	else {
688 		root->i_atime.tv_sec = local_to_gmt(s, le32_to_cpu(de->read_date));
689 		root->i_atime.tv_nsec = 0;
690 		root->i_mtime.tv_sec = local_to_gmt(s, le32_to_cpu(de->write_date));
691 		root->i_mtime.tv_nsec = 0;
692 		root->i_ctime.tv_sec = local_to_gmt(s, le32_to_cpu(de->creation_date));
693 		root->i_ctime.tv_nsec = 0;
694 		hpfs_i(root)->i_ea_size = le32_to_cpu(de->ea_size);
695 		hpfs_i(root)->i_parent_dir = root->i_ino;
696 		if (root->i_size == -1)
697 			root->i_size = 2048;
698 		if (root->i_blocks == -1)
699 			root->i_blocks = 5;
700 		hpfs_brelse4(&qbh);
701 	}
702 	hpfs_unlock(s);
703 	return 0;
704 
705 bail4:	brelse(bh2);
706 bail3:	brelse(bh1);
707 bail2:	brelse(bh0);
708 bail1:
709 bail0:
710 	hpfs_unlock(s);
711 	free_sbi(sbi);
712 	return -EINVAL;
713 }
714 
715 static struct dentry *hpfs_mount(struct file_system_type *fs_type,
716 	int flags, const char *dev_name, void *data)
717 {
718 	return mount_bdev(fs_type, flags, dev_name, data, hpfs_fill_super);
719 }
720 
721 static struct file_system_type hpfs_fs_type = {
722 	.owner		= THIS_MODULE,
723 	.name		= "hpfs",
724 	.mount		= hpfs_mount,
725 	.kill_sb	= kill_block_super,
726 	.fs_flags	= FS_REQUIRES_DEV,
727 };
728 MODULE_ALIAS_FS("hpfs");
729 
730 static int __init init_hpfs_fs(void)
731 {
732 	int err = init_inodecache();
733 	if (err)
734 		goto out1;
735 	err = register_filesystem(&hpfs_fs_type);
736 	if (err)
737 		goto out;
738 	return 0;
739 out:
740 	destroy_inodecache();
741 out1:
742 	return err;
743 }
744 
745 static void __exit exit_hpfs_fs(void)
746 {
747 	unregister_filesystem(&hpfs_fs_type);
748 	destroy_inodecache();
749 }
750 
751 module_init(init_hpfs_fs)
752 module_exit(exit_hpfs_fs)
753 MODULE_LICENSE("GPL");
754