xref: /openbmc/linux/fs/hpfs/super.c (revision 55eb9a6c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/fs/hpfs/super.c
4  *
5  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
6  *
7  *  mounting, unmounting, error handling
8  */
9 
10 #include "hpfs_fn.h"
11 #include <linux/module.h>
12 #include <linux/parser.h>
13 #include <linux/init.h>
14 #include <linux/statfs.h>
15 #include <linux/magic.h>
16 #include <linux/sched.h>
17 #include <linux/bitmap.h>
18 #include <linux/slab.h>
19 #include <linux/seq_file.h>
20 
21 /* Mark the filesystem dirty, so that chkdsk checks it when os/2 booted */
22 
23 static void mark_dirty(struct super_block *s, int remount)
24 {
25 	if (hpfs_sb(s)->sb_chkdsk && (remount || !sb_rdonly(s))) {
26 		struct buffer_head *bh;
27 		struct hpfs_spare_block *sb;
28 		if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
29 			sb->dirty = 1;
30 			sb->old_wrote = 0;
31 			mark_buffer_dirty(bh);
32 			sync_dirty_buffer(bh);
33 			brelse(bh);
34 		}
35 	}
36 }
37 
38 /* Mark the filesystem clean (mark it dirty for chkdsk if chkdsk==2 or if there
39    were errors) */
40 
41 static void unmark_dirty(struct super_block *s)
42 {
43 	struct buffer_head *bh;
44 	struct hpfs_spare_block *sb;
45 	if (sb_rdonly(s)) return;
46 	sync_blockdev(s->s_bdev);
47 	if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
48 		sb->dirty = hpfs_sb(s)->sb_chkdsk > 1 - hpfs_sb(s)->sb_was_error;
49 		sb->old_wrote = hpfs_sb(s)->sb_chkdsk >= 2 && !hpfs_sb(s)->sb_was_error;
50 		mark_buffer_dirty(bh);
51 		sync_dirty_buffer(bh);
52 		brelse(bh);
53 	}
54 }
55 
56 /* Filesystem error... */
57 void hpfs_error(struct super_block *s, const char *fmt, ...)
58 {
59 	struct va_format vaf;
60 	va_list args;
61 
62 	va_start(args, fmt);
63 
64 	vaf.fmt = fmt;
65 	vaf.va = &args;
66 
67 	pr_err("filesystem error: %pV", &vaf);
68 
69 	va_end(args);
70 
71 	if (!hpfs_sb(s)->sb_was_error) {
72 		if (hpfs_sb(s)->sb_err == 2) {
73 			pr_cont("; crashing the system because you wanted it\n");
74 			mark_dirty(s, 0);
75 			panic("HPFS panic");
76 		} else if (hpfs_sb(s)->sb_err == 1) {
77 			if (sb_rdonly(s))
78 				pr_cont("; already mounted read-only\n");
79 			else {
80 				pr_cont("; remounting read-only\n");
81 				mark_dirty(s, 0);
82 				s->s_flags |= SB_RDONLY;
83 			}
84 		} else if (sb_rdonly(s))
85 				pr_cont("; going on - but anything won't be destroyed because it's read-only\n");
86 		else
87 			pr_cont("; corrupted filesystem mounted read/write - your computer will explode within 20 seconds ... but you wanted it so!\n");
88 	} else
89 		pr_cont("\n");
90 	hpfs_sb(s)->sb_was_error = 1;
91 }
92 
93 /*
94  * A little trick to detect cycles in many hpfs structures and don't let the
95  * kernel crash on corrupted filesystem. When first called, set c2 to 0.
96  *
97  * BTW. chkdsk doesn't detect cycles correctly. When I had 2 lost directories
98  * nested each in other, chkdsk locked up happilly.
99  */
100 
101 int hpfs_stop_cycles(struct super_block *s, int key, int *c1, int *c2,
102 		char *msg)
103 {
104 	if (*c2 && *c1 == key) {
105 		hpfs_error(s, "cycle detected on key %08x in %s", key, msg);
106 		return 1;
107 	}
108 	(*c2)++;
109 	if (!((*c2 - 1) & *c2)) *c1 = key;
110 	return 0;
111 }
112 
113 static void free_sbi(struct hpfs_sb_info *sbi)
114 {
115 	kfree(sbi->sb_cp_table);
116 	kfree(sbi->sb_bmp_dir);
117 	kfree(sbi);
118 }
119 
120 static void lazy_free_sbi(struct rcu_head *rcu)
121 {
122 	free_sbi(container_of(rcu, struct hpfs_sb_info, rcu));
123 }
124 
125 static void hpfs_put_super(struct super_block *s)
126 {
127 	hpfs_lock(s);
128 	unmark_dirty(s);
129 	hpfs_unlock(s);
130 	call_rcu(&hpfs_sb(s)->rcu, lazy_free_sbi);
131 }
132 
133 static unsigned hpfs_count_one_bitmap(struct super_block *s, secno secno)
134 {
135 	struct quad_buffer_head qbh;
136 	unsigned long *bits;
137 	unsigned count;
138 
139 	bits = hpfs_map_4sectors(s, secno, &qbh, 0);
140 	if (!bits)
141 		return (unsigned)-1;
142 	count = bitmap_weight(bits, 2048 * BITS_PER_BYTE);
143 	hpfs_brelse4(&qbh);
144 	return count;
145 }
146 
147 static unsigned count_bitmaps(struct super_block *s)
148 {
149 	unsigned n, count, n_bands;
150 	n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
151 	count = 0;
152 	for (n = 0; n < COUNT_RD_AHEAD; n++) {
153 		hpfs_prefetch_bitmap(s, n);
154 	}
155 	for (n = 0; n < n_bands; n++) {
156 		unsigned c;
157 		hpfs_prefetch_bitmap(s, n + COUNT_RD_AHEAD);
158 		c = hpfs_count_one_bitmap(s, le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[n]));
159 		if (c != (unsigned)-1)
160 			count += c;
161 	}
162 	return count;
163 }
164 
165 unsigned hpfs_get_free_dnodes(struct super_block *s)
166 {
167 	struct hpfs_sb_info *sbi = hpfs_sb(s);
168 	if (sbi->sb_n_free_dnodes == (unsigned)-1) {
169 		unsigned c = hpfs_count_one_bitmap(s, sbi->sb_dmap);
170 		if (c == (unsigned)-1)
171 			return 0;
172 		sbi->sb_n_free_dnodes = c;
173 	}
174 	return sbi->sb_n_free_dnodes;
175 }
176 
177 static int hpfs_statfs(struct dentry *dentry, struct kstatfs *buf)
178 {
179 	struct super_block *s = dentry->d_sb;
180 	struct hpfs_sb_info *sbi = hpfs_sb(s);
181 	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
182 
183 	hpfs_lock(s);
184 
185 	if (sbi->sb_n_free == (unsigned)-1)
186 		sbi->sb_n_free = count_bitmaps(s);
187 
188 	buf->f_type = s->s_magic;
189 	buf->f_bsize = 512;
190 	buf->f_blocks = sbi->sb_fs_size;
191 	buf->f_bfree = sbi->sb_n_free;
192 	buf->f_bavail = sbi->sb_n_free;
193 	buf->f_files = sbi->sb_dirband_size / 4;
194 	buf->f_ffree = hpfs_get_free_dnodes(s);
195 	buf->f_fsid = u64_to_fsid(id);
196 	buf->f_namelen = 254;
197 
198 	hpfs_unlock(s);
199 
200 	return 0;
201 }
202 
203 
204 long hpfs_ioctl(struct file *file, unsigned cmd, unsigned long arg)
205 {
206 	switch (cmd) {
207 		case FITRIM: {
208 			struct fstrim_range range;
209 			secno n_trimmed;
210 			int r;
211 			if (!capable(CAP_SYS_ADMIN))
212 				return -EPERM;
213 			if (copy_from_user(&range, (struct fstrim_range __user *)arg, sizeof(range)))
214 				return -EFAULT;
215 			r = hpfs_trim_fs(file_inode(file)->i_sb, range.start >> 9, (range.start + range.len) >> 9, (range.minlen + 511) >> 9, &n_trimmed);
216 			if (r)
217 				return r;
218 			range.len = (u64)n_trimmed << 9;
219 			if (copy_to_user((struct fstrim_range __user *)arg, &range, sizeof(range)))
220 				return -EFAULT;
221 			return 0;
222 		}
223 		default: {
224 			return -ENOIOCTLCMD;
225 		}
226 	}
227 }
228 
229 
230 static struct kmem_cache * hpfs_inode_cachep;
231 
232 static struct inode *hpfs_alloc_inode(struct super_block *sb)
233 {
234 	struct hpfs_inode_info *ei;
235 	ei = alloc_inode_sb(sb, hpfs_inode_cachep, GFP_NOFS);
236 	if (!ei)
237 		return NULL;
238 	return &ei->vfs_inode;
239 }
240 
241 static void hpfs_free_inode(struct inode *inode)
242 {
243 	kmem_cache_free(hpfs_inode_cachep, hpfs_i(inode));
244 }
245 
246 static void init_once(void *foo)
247 {
248 	struct hpfs_inode_info *ei = (struct hpfs_inode_info *) foo;
249 
250 	inode_init_once(&ei->vfs_inode);
251 }
252 
253 static int init_inodecache(void)
254 {
255 	hpfs_inode_cachep = kmem_cache_create("hpfs_inode_cache",
256 					     sizeof(struct hpfs_inode_info),
257 					     0, (SLAB_RECLAIM_ACCOUNT|
258 						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
259 					     init_once);
260 	if (hpfs_inode_cachep == NULL)
261 		return -ENOMEM;
262 	return 0;
263 }
264 
265 static void destroy_inodecache(void)
266 {
267 	/*
268 	 * Make sure all delayed rcu free inodes are flushed before we
269 	 * destroy cache.
270 	 */
271 	rcu_barrier();
272 	kmem_cache_destroy(hpfs_inode_cachep);
273 }
274 
275 /*
276  * A tiny parser for option strings, stolen from dosfs.
277  * Stolen again from read-only hpfs.
278  * And updated for table-driven option parsing.
279  */
280 
281 enum {
282 	Opt_help, Opt_uid, Opt_gid, Opt_umask, Opt_case_lower, Opt_case_asis,
283 	Opt_check_none, Opt_check_normal, Opt_check_strict,
284 	Opt_err_cont, Opt_err_ro, Opt_err_panic,
285 	Opt_eas_no, Opt_eas_ro, Opt_eas_rw,
286 	Opt_chkdsk_no, Opt_chkdsk_errors, Opt_chkdsk_always,
287 	Opt_timeshift, Opt_err,
288 };
289 
290 static const match_table_t tokens = {
291 	{Opt_help, "help"},
292 	{Opt_uid, "uid=%u"},
293 	{Opt_gid, "gid=%u"},
294 	{Opt_umask, "umask=%o"},
295 	{Opt_case_lower, "case=lower"},
296 	{Opt_case_asis, "case=asis"},
297 	{Opt_check_none, "check=none"},
298 	{Opt_check_normal, "check=normal"},
299 	{Opt_check_strict, "check=strict"},
300 	{Opt_err_cont, "errors=continue"},
301 	{Opt_err_ro, "errors=remount-ro"},
302 	{Opt_err_panic, "errors=panic"},
303 	{Opt_eas_no, "eas=no"},
304 	{Opt_eas_ro, "eas=ro"},
305 	{Opt_eas_rw, "eas=rw"},
306 	{Opt_chkdsk_no, "chkdsk=no"},
307 	{Opt_chkdsk_errors, "chkdsk=errors"},
308 	{Opt_chkdsk_always, "chkdsk=always"},
309 	{Opt_timeshift, "timeshift=%d"},
310 	{Opt_err, NULL},
311 };
312 
313 static int parse_opts(char *opts, kuid_t *uid, kgid_t *gid, umode_t *umask,
314 		      int *lowercase, int *eas, int *chk, int *errs,
315 		      int *chkdsk, int *timeshift)
316 {
317 	char *p;
318 	int option;
319 
320 	if (!opts)
321 		return 1;
322 
323 	/*pr_info("Parsing opts: '%s'\n",opts);*/
324 
325 	while ((p = strsep(&opts, ",")) != NULL) {
326 		substring_t args[MAX_OPT_ARGS];
327 		int token;
328 		if (!*p)
329 			continue;
330 
331 		token = match_token(p, tokens, args);
332 		switch (token) {
333 		case Opt_help:
334 			return 2;
335 		case Opt_uid:
336 			if (match_int(args, &option))
337 				return 0;
338 			*uid = make_kuid(current_user_ns(), option);
339 			if (!uid_valid(*uid))
340 				return 0;
341 			break;
342 		case Opt_gid:
343 			if (match_int(args, &option))
344 				return 0;
345 			*gid = make_kgid(current_user_ns(), option);
346 			if (!gid_valid(*gid))
347 				return 0;
348 			break;
349 		case Opt_umask:
350 			if (match_octal(args, &option))
351 				return 0;
352 			*umask = option;
353 			break;
354 		case Opt_case_lower:
355 			*lowercase = 1;
356 			break;
357 		case Opt_case_asis:
358 			*lowercase = 0;
359 			break;
360 		case Opt_check_none:
361 			*chk = 0;
362 			break;
363 		case Opt_check_normal:
364 			*chk = 1;
365 			break;
366 		case Opt_check_strict:
367 			*chk = 2;
368 			break;
369 		case Opt_err_cont:
370 			*errs = 0;
371 			break;
372 		case Opt_err_ro:
373 			*errs = 1;
374 			break;
375 		case Opt_err_panic:
376 			*errs = 2;
377 			break;
378 		case Opt_eas_no:
379 			*eas = 0;
380 			break;
381 		case Opt_eas_ro:
382 			*eas = 1;
383 			break;
384 		case Opt_eas_rw:
385 			*eas = 2;
386 			break;
387 		case Opt_chkdsk_no:
388 			*chkdsk = 0;
389 			break;
390 		case Opt_chkdsk_errors:
391 			*chkdsk = 1;
392 			break;
393 		case Opt_chkdsk_always:
394 			*chkdsk = 2;
395 			break;
396 		case Opt_timeshift:
397 		{
398 			int m = 1;
399 			char *rhs = args[0].from;
400 			if (!rhs || !*rhs)
401 				return 0;
402 			if (*rhs == '-') m = -1;
403 			if (*rhs == '+' || *rhs == '-') rhs++;
404 			*timeshift = simple_strtoul(rhs, &rhs, 0) * m;
405 			if (*rhs)
406 				return 0;
407 			break;
408 		}
409 		default:
410 			return 0;
411 		}
412 	}
413 	return 1;
414 }
415 
416 static inline void hpfs_help(void)
417 {
418 	pr_info("\n\
419 HPFS filesystem options:\n\
420       help              do not mount and display this text\n\
421       uid=xxx           set uid of files that don't have uid specified in eas\n\
422       gid=xxx           set gid of files that don't have gid specified in eas\n\
423       umask=xxx         set mode of files that don't have mode specified in eas\n\
424       case=lower        lowercase all files\n\
425       case=asis         do not lowercase files (default)\n\
426       check=none        no fs checks - kernel may crash on corrupted filesystem\n\
427       check=normal      do some checks - it should not crash (default)\n\
428       check=strict      do extra time-consuming checks, used for debugging\n\
429       errors=continue   continue on errors\n\
430       errors=remount-ro remount read-only if errors found (default)\n\
431       errors=panic      panic on errors\n\
432       chkdsk=no         do not mark fs for chkdsking even if there were errors\n\
433       chkdsk=errors     mark fs dirty if errors found (default)\n\
434       chkdsk=always     always mark fs dirty - used for debugging\n\
435       eas=no            ignore extended attributes\n\
436       eas=ro            read but do not write extended attributes\n\
437       eas=rw            r/w eas => enables chmod, chown, mknod, ln -s (default)\n\
438       timeshift=nnn	add nnn seconds to file times\n\
439 \n");
440 }
441 
442 static int hpfs_remount_fs(struct super_block *s, int *flags, char *data)
443 {
444 	kuid_t uid;
445 	kgid_t gid;
446 	umode_t umask;
447 	int lowercase, eas, chk, errs, chkdsk, timeshift;
448 	int o;
449 	struct hpfs_sb_info *sbi = hpfs_sb(s);
450 
451 	sync_filesystem(s);
452 
453 	*flags |= SB_NOATIME;
454 
455 	hpfs_lock(s);
456 	uid = sbi->sb_uid; gid = sbi->sb_gid;
457 	umask = 0777 & ~sbi->sb_mode;
458 	lowercase = sbi->sb_lowercase;
459 	eas = sbi->sb_eas; chk = sbi->sb_chk; chkdsk = sbi->sb_chkdsk;
460 	errs = sbi->sb_err; timeshift = sbi->sb_timeshift;
461 
462 	if (!(o = parse_opts(data, &uid, &gid, &umask, &lowercase,
463 	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
464 		pr_err("bad mount options.\n");
465 		goto out_err;
466 	}
467 	if (o == 2) {
468 		hpfs_help();
469 		goto out_err;
470 	}
471 	if (timeshift != sbi->sb_timeshift) {
472 		pr_err("timeshift can't be changed using remount.\n");
473 		goto out_err;
474 	}
475 
476 	unmark_dirty(s);
477 
478 	sbi->sb_uid = uid; sbi->sb_gid = gid;
479 	sbi->sb_mode = 0777 & ~umask;
480 	sbi->sb_lowercase = lowercase;
481 	sbi->sb_eas = eas; sbi->sb_chk = chk; sbi->sb_chkdsk = chkdsk;
482 	sbi->sb_err = errs; sbi->sb_timeshift = timeshift;
483 
484 	if (!(*flags & SB_RDONLY)) mark_dirty(s, 1);
485 
486 	hpfs_unlock(s);
487 	return 0;
488 
489 out_err:
490 	hpfs_unlock(s);
491 	return -EINVAL;
492 }
493 
494 static int hpfs_show_options(struct seq_file *seq, struct dentry *root)
495 {
496 	struct hpfs_sb_info *sbi = hpfs_sb(root->d_sb);
497 
498 	seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, sbi->sb_uid));
499 	seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, sbi->sb_gid));
500 	seq_printf(seq, ",umask=%03o", (~sbi->sb_mode & 0777));
501 	if (sbi->sb_lowercase)
502 		seq_printf(seq, ",case=lower");
503 	if (!sbi->sb_chk)
504 		seq_printf(seq, ",check=none");
505 	if (sbi->sb_chk == 2)
506 		seq_printf(seq, ",check=strict");
507 	if (!sbi->sb_err)
508 		seq_printf(seq, ",errors=continue");
509 	if (sbi->sb_err == 2)
510 		seq_printf(seq, ",errors=panic");
511 	if (!sbi->sb_chkdsk)
512 		seq_printf(seq, ",chkdsk=no");
513 	if (sbi->sb_chkdsk == 2)
514 		seq_printf(seq, ",chkdsk=always");
515 	if (!sbi->sb_eas)
516 		seq_printf(seq, ",eas=no");
517 	if (sbi->sb_eas == 1)
518 		seq_printf(seq, ",eas=ro");
519 	if (sbi->sb_timeshift)
520 		seq_printf(seq, ",timeshift=%d", sbi->sb_timeshift);
521 	return 0;
522 }
523 
524 /* Super operations */
525 
526 static const struct super_operations hpfs_sops =
527 {
528 	.alloc_inode	= hpfs_alloc_inode,
529 	.free_inode	= hpfs_free_inode,
530 	.evict_inode	= hpfs_evict_inode,
531 	.put_super	= hpfs_put_super,
532 	.statfs		= hpfs_statfs,
533 	.remount_fs	= hpfs_remount_fs,
534 	.show_options	= hpfs_show_options,
535 };
536 
537 static int hpfs_fill_super(struct super_block *s, void *options, int silent)
538 {
539 	struct buffer_head *bh0, *bh1, *bh2;
540 	struct hpfs_boot_block *bootblock;
541 	struct hpfs_super_block *superblock;
542 	struct hpfs_spare_block *spareblock;
543 	struct hpfs_sb_info *sbi;
544 	struct inode *root;
545 
546 	kuid_t uid;
547 	kgid_t gid;
548 	umode_t umask;
549 	int lowercase, eas, chk, errs, chkdsk, timeshift;
550 
551 	dnode_secno root_dno;
552 	struct hpfs_dirent *de = NULL;
553 	struct quad_buffer_head qbh;
554 
555 	int o;
556 
557 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
558 	if (!sbi) {
559 		return -ENOMEM;
560 	}
561 	s->s_fs_info = sbi;
562 
563 	mutex_init(&sbi->hpfs_mutex);
564 	hpfs_lock(s);
565 
566 	uid = current_uid();
567 	gid = current_gid();
568 	umask = current_umask();
569 	lowercase = 0;
570 	eas = 2;
571 	chk = 1;
572 	errs = 1;
573 	chkdsk = 1;
574 	timeshift = 0;
575 
576 	if (!(o = parse_opts(options, &uid, &gid, &umask, &lowercase,
577 	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
578 		pr_err("bad mount options.\n");
579 		goto bail0;
580 	}
581 	if (o==2) {
582 		hpfs_help();
583 		goto bail0;
584 	}
585 
586 	/*sbi->sb_mounting = 1;*/
587 	sb_set_blocksize(s, 512);
588 	sbi->sb_fs_size = -1;
589 	if (!(bootblock = hpfs_map_sector(s, 0, &bh0, 0))) goto bail1;
590 	if (!(superblock = hpfs_map_sector(s, 16, &bh1, 1))) goto bail2;
591 	if (!(spareblock = hpfs_map_sector(s, 17, &bh2, 0))) goto bail3;
592 
593 	/* Check magics */
594 	if (/*le16_to_cpu(bootblock->magic) != BB_MAGIC
595 	    ||*/ le32_to_cpu(superblock->magic) != SB_MAGIC
596 	    || le32_to_cpu(spareblock->magic) != SP_MAGIC) {
597 		if (!silent)
598 			pr_err("Bad magic ... probably not HPFS\n");
599 		goto bail4;
600 	}
601 
602 	/* Check version */
603 	if (!sb_rdonly(s) && superblock->funcversion != 2 && superblock->funcversion != 3) {
604 		pr_err("Bad version %d,%d. Mount readonly to go around\n",
605 			(int)superblock->version, (int)superblock->funcversion);
606 		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");
607 		goto bail4;
608 	}
609 
610 	s->s_flags |= SB_NOATIME;
611 
612 	/* Fill superblock stuff */
613 	s->s_magic = HPFS_SUPER_MAGIC;
614 	s->s_op = &hpfs_sops;
615 	s->s_d_op = &hpfs_dentry_operations;
616 	s->s_time_min =  local_to_gmt(s, 0);
617 	s->s_time_max =  local_to_gmt(s, U32_MAX);
618 
619 	sbi->sb_root = le32_to_cpu(superblock->root);
620 	sbi->sb_fs_size = le32_to_cpu(superblock->n_sectors);
621 	sbi->sb_bitmaps = le32_to_cpu(superblock->bitmaps);
622 	sbi->sb_dirband_start = le32_to_cpu(superblock->dir_band_start);
623 	sbi->sb_dirband_size = le32_to_cpu(superblock->n_dir_band);
624 	sbi->sb_dmap = le32_to_cpu(superblock->dir_band_bitmap);
625 	sbi->sb_uid = uid;
626 	sbi->sb_gid = gid;
627 	sbi->sb_mode = 0777 & ~umask;
628 	sbi->sb_n_free = -1;
629 	sbi->sb_n_free_dnodes = -1;
630 	sbi->sb_lowercase = lowercase;
631 	sbi->sb_eas = eas;
632 	sbi->sb_chk = chk;
633 	sbi->sb_chkdsk = chkdsk;
634 	sbi->sb_err = errs;
635 	sbi->sb_timeshift = timeshift;
636 	sbi->sb_was_error = 0;
637 	sbi->sb_cp_table = NULL;
638 	sbi->sb_c_bitmap = -1;
639 	sbi->sb_max_fwd_alloc = 0xffffff;
640 
641 	if (sbi->sb_fs_size >= 0x80000000) {
642 		hpfs_error(s, "invalid size in superblock: %08x",
643 			(unsigned)sbi->sb_fs_size);
644 		goto bail4;
645 	}
646 
647 	if (spareblock->n_spares_used)
648 		hpfs_load_hotfix_map(s, spareblock);
649 
650 	/* Load bitmap directory */
651 	if (!(sbi->sb_bmp_dir = hpfs_load_bitmap_directory(s, le32_to_cpu(superblock->bitmaps))))
652 		goto bail4;
653 
654 	/* Check for general fs errors*/
655 	if (spareblock->dirty && !spareblock->old_wrote) {
656 		if (errs == 2) {
657 			pr_err("Improperly stopped, not mounted\n");
658 			goto bail4;
659 		}
660 		hpfs_error(s, "improperly stopped");
661 	}
662 
663 	if (!sb_rdonly(s)) {
664 		spareblock->dirty = 1;
665 		spareblock->old_wrote = 0;
666 		mark_buffer_dirty(bh2);
667 	}
668 
669 	if (le32_to_cpu(spareblock->n_dnode_spares) != le32_to_cpu(spareblock->n_dnode_spares_free)) {
670 		if (errs >= 2) {
671 			pr_err("Spare dnodes used, try chkdsk\n");
672 			mark_dirty(s, 0);
673 			goto bail4;
674 		}
675 		hpfs_error(s, "warning: spare dnodes used, try chkdsk");
676 		if (errs == 0)
677 			pr_err("Proceeding, but your filesystem could be corrupted if you delete files or directories\n");
678 	}
679 	if (chk) {
680 		unsigned a;
681 		if (le32_to_cpu(superblock->dir_band_end) - le32_to_cpu(superblock->dir_band_start) + 1 != le32_to_cpu(superblock->n_dir_band) ||
682 		    le32_to_cpu(superblock->dir_band_end) < le32_to_cpu(superblock->dir_band_start) || le32_to_cpu(superblock->n_dir_band) > 0x4000) {
683 			hpfs_error(s, "dir band size mismatch: dir_band_start==%08x, dir_band_end==%08x, n_dir_band==%08x",
684 				le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->dir_band_end), le32_to_cpu(superblock->n_dir_band));
685 			goto bail4;
686 		}
687 		a = sbi->sb_dirband_size;
688 		sbi->sb_dirband_size = 0;
689 		if (hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->n_dir_band), "dir_band") ||
690 		    hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_bitmap), 4, "dir_band_bitmap") ||
691 		    hpfs_chk_sectors(s, le32_to_cpu(superblock->bitmaps), 4, "bitmaps")) {
692 			mark_dirty(s, 0);
693 			goto bail4;
694 		}
695 		sbi->sb_dirband_size = a;
696 	} else
697 		pr_err("You really don't want any checks? You are crazy...\n");
698 
699 	/* Load code page table */
700 	if (le32_to_cpu(spareblock->n_code_pages))
701 		if (!(sbi->sb_cp_table = hpfs_load_code_page(s, le32_to_cpu(spareblock->code_page_dir))))
702 			pr_err("code page support is disabled\n");
703 
704 	brelse(bh2);
705 	brelse(bh1);
706 	brelse(bh0);
707 
708 	root = iget_locked(s, sbi->sb_root);
709 	if (!root)
710 		goto bail0;
711 	hpfs_init_inode(root);
712 	hpfs_read_inode(root);
713 	unlock_new_inode(root);
714 	s->s_root = d_make_root(root);
715 	if (!s->s_root)
716 		goto bail0;
717 
718 	/*
719 	 * find the root directory's . pointer & finish filling in the inode
720 	 */
721 
722 	root_dno = hpfs_fnode_dno(s, sbi->sb_root);
723 	if (root_dno)
724 		de = map_dirent(root, root_dno, "\001\001", 2, NULL, &qbh);
725 	if (!de)
726 		hpfs_error(s, "unable to find root dir");
727 	else {
728 		root->i_atime.tv_sec = local_to_gmt(s, le32_to_cpu(de->read_date));
729 		root->i_atime.tv_nsec = 0;
730 		root->i_mtime.tv_sec = local_to_gmt(s, le32_to_cpu(de->write_date));
731 		root->i_mtime.tv_nsec = 0;
732 		root->i_ctime.tv_sec = local_to_gmt(s, le32_to_cpu(de->creation_date));
733 		root->i_ctime.tv_nsec = 0;
734 		hpfs_i(root)->i_ea_size = le32_to_cpu(de->ea_size);
735 		hpfs_i(root)->i_parent_dir = root->i_ino;
736 		if (root->i_size == -1)
737 			root->i_size = 2048;
738 		if (root->i_blocks == -1)
739 			root->i_blocks = 5;
740 		hpfs_brelse4(&qbh);
741 	}
742 	hpfs_unlock(s);
743 	return 0;
744 
745 bail4:	brelse(bh2);
746 bail3:	brelse(bh1);
747 bail2:	brelse(bh0);
748 bail1:
749 bail0:
750 	hpfs_unlock(s);
751 	free_sbi(sbi);
752 	return -EINVAL;
753 }
754 
755 static struct dentry *hpfs_mount(struct file_system_type *fs_type,
756 	int flags, const char *dev_name, void *data)
757 {
758 	return mount_bdev(fs_type, flags, dev_name, data, hpfs_fill_super);
759 }
760 
761 static struct file_system_type hpfs_fs_type = {
762 	.owner		= THIS_MODULE,
763 	.name		= "hpfs",
764 	.mount		= hpfs_mount,
765 	.kill_sb	= kill_block_super,
766 	.fs_flags	= FS_REQUIRES_DEV,
767 };
768 MODULE_ALIAS_FS("hpfs");
769 
770 static int __init init_hpfs_fs(void)
771 {
772 	int err = init_inodecache();
773 	if (err)
774 		goto out1;
775 	err = register_filesystem(&hpfs_fs_type);
776 	if (err)
777 		goto out;
778 	return 0;
779 out:
780 	destroy_inodecache();
781 out1:
782 	return err;
783 }
784 
785 static void __exit exit_hpfs_fs(void)
786 {
787 	unregister_filesystem(&hpfs_fs_type);
788 	destroy_inodecache();
789 }
790 
791 module_init(init_hpfs_fs)
792 module_exit(exit_hpfs_fs)
793 MODULE_LICENSE("GPL");
794