xref: /openbmc/linux/fs/hpfs/super.c (revision 2572f00d)
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 void hpfs_error(struct super_block *s, const char *fmt, ...)
56 {
57 	struct va_format vaf;
58 	va_list args;
59 
60 	va_start(args, fmt);
61 
62 	vaf.fmt = fmt;
63 	vaf.va = &args;
64 
65 	pr_err("filesystem error: %pV", &vaf);
66 
67 	va_end(args);
68 
69 	if (!hpfs_sb(s)->sb_was_error) {
70 		if (hpfs_sb(s)->sb_err == 2) {
71 			pr_cont("; crashing the system because you wanted it\n");
72 			mark_dirty(s, 0);
73 			panic("HPFS panic");
74 		} else if (hpfs_sb(s)->sb_err == 1) {
75 			if (s->s_flags & MS_RDONLY)
76 				pr_cont("; already mounted read-only\n");
77 			else {
78 				pr_cont("; remounting read-only\n");
79 				mark_dirty(s, 0);
80 				s->s_flags |= MS_RDONLY;
81 			}
82 		} else if (s->s_flags & MS_RDONLY)
83 				pr_cont("; going on - but anything won't be destroyed because it's read-only\n");
84 		else
85 			pr_cont("; corrupted filesystem mounted read/write - your computer will explode within 20 seconds ... but you wanted it so!\n");
86 	} else
87 		pr_cont("\n");
88 	hpfs_sb(s)->sb_was_error = 1;
89 }
90 
91 /*
92  * A little trick to detect cycles in many hpfs structures and don't let the
93  * kernel crash on corrupted filesystem. When first called, set c2 to 0.
94  *
95  * BTW. chkdsk doesn't detect cycles correctly. When I had 2 lost directories
96  * nested each in other, chkdsk locked up happilly.
97  */
98 
99 int hpfs_stop_cycles(struct super_block *s, int key, int *c1, int *c2,
100 		char *msg)
101 {
102 	if (*c2 && *c1 == key) {
103 		hpfs_error(s, "cycle detected on key %08x in %s", key, msg);
104 		return 1;
105 	}
106 	(*c2)++;
107 	if (!((*c2 - 1) & *c2)) *c1 = key;
108 	return 0;
109 }
110 
111 static void free_sbi(struct hpfs_sb_info *sbi)
112 {
113 	kfree(sbi->sb_cp_table);
114 	kfree(sbi->sb_bmp_dir);
115 	kfree(sbi);
116 }
117 
118 static void lazy_free_sbi(struct rcu_head *rcu)
119 {
120 	free_sbi(container_of(rcu, struct hpfs_sb_info, rcu));
121 }
122 
123 static void hpfs_put_super(struct super_block *s)
124 {
125 	hpfs_lock(s);
126 	unmark_dirty(s);
127 	hpfs_unlock(s);
128 	call_rcu(&hpfs_sb(s)->rcu, lazy_free_sbi);
129 }
130 
131 static unsigned hpfs_count_one_bitmap(struct super_block *s, secno secno)
132 {
133 	struct quad_buffer_head qbh;
134 	unsigned long *bits;
135 	unsigned count;
136 
137 	bits = hpfs_map_4sectors(s, secno, &qbh, 0);
138 	if (!bits)
139 		return (unsigned)-1;
140 	count = bitmap_weight(bits, 2048 * BITS_PER_BYTE);
141 	hpfs_brelse4(&qbh);
142 	return count;
143 }
144 
145 static unsigned count_bitmaps(struct super_block *s)
146 {
147 	unsigned n, count, n_bands;
148 	n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
149 	count = 0;
150 	for (n = 0; n < COUNT_RD_AHEAD; n++) {
151 		hpfs_prefetch_bitmap(s, n);
152 	}
153 	for (n = 0; n < n_bands; n++) {
154 		unsigned c;
155 		hpfs_prefetch_bitmap(s, n + COUNT_RD_AHEAD);
156 		c = hpfs_count_one_bitmap(s, le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[n]));
157 		if (c != (unsigned)-1)
158 			count += c;
159 	}
160 	return count;
161 }
162 
163 unsigned hpfs_get_free_dnodes(struct super_block *s)
164 {
165 	struct hpfs_sb_info *sbi = hpfs_sb(s);
166 	if (sbi->sb_n_free_dnodes == (unsigned)-1) {
167 		unsigned c = hpfs_count_one_bitmap(s, sbi->sb_dmap);
168 		if (c == (unsigned)-1)
169 			return 0;
170 		sbi->sb_n_free_dnodes = c;
171 	}
172 	return sbi->sb_n_free_dnodes;
173 }
174 
175 static int hpfs_statfs(struct dentry *dentry, struct kstatfs *buf)
176 {
177 	struct super_block *s = dentry->d_sb;
178 	struct hpfs_sb_info *sbi = hpfs_sb(s);
179 	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
180 
181 	hpfs_lock(s);
182 
183 	if (sbi->sb_n_free == (unsigned)-1)
184 		sbi->sb_n_free = count_bitmaps(s);
185 
186 	buf->f_type = s->s_magic;
187 	buf->f_bsize = 512;
188 	buf->f_blocks = sbi->sb_fs_size;
189 	buf->f_bfree = sbi->sb_n_free;
190 	buf->f_bavail = sbi->sb_n_free;
191 	buf->f_files = sbi->sb_dirband_size / 4;
192 	buf->f_ffree = hpfs_get_free_dnodes(s);
193 	buf->f_fsid.val[0] = (u32)id;
194 	buf->f_fsid.val[1] = (u32)(id >> 32);
195 	buf->f_namelen = 254;
196 
197 	hpfs_unlock(s);
198 
199 	return 0;
200 }
201 
202 
203 long hpfs_ioctl(struct file *file, unsigned cmd, unsigned long arg)
204 {
205 	switch (cmd) {
206 		case FITRIM: {
207 			struct fstrim_range range;
208 			secno n_trimmed;
209 			int r;
210 			if (!capable(CAP_SYS_ADMIN))
211 				return -EPERM;
212 			if (copy_from_user(&range, (struct fstrim_range __user *)arg, sizeof(range)))
213 				return -EFAULT;
214 			r = hpfs_trim_fs(file_inode(file)->i_sb, range.start >> 9, (range.start + range.len) >> 9, (range.minlen + 511) >> 9, &n_trimmed);
215 			if (r)
216 				return r;
217 			range.len = (u64)n_trimmed << 9;
218 			if (copy_to_user((struct fstrim_range __user *)arg, &range, sizeof(range)))
219 				return -EFAULT;
220 			return 0;
221 		}
222 		default: {
223 			return -ENOIOCTLCMD;
224 		}
225 	}
226 }
227 
228 
229 static struct kmem_cache * hpfs_inode_cachep;
230 
231 static struct inode *hpfs_alloc_inode(struct super_block *sb)
232 {
233 	struct hpfs_inode_info *ei;
234 	ei = kmem_cache_alloc(hpfs_inode_cachep, GFP_NOFS);
235 	if (!ei)
236 		return NULL;
237 	ei->vfs_inode.i_version = 1;
238 	return &ei->vfs_inode;
239 }
240 
241 static void hpfs_i_callback(struct rcu_head *head)
242 {
243 	struct inode *inode = container_of(head, struct inode, i_rcu);
244 	kmem_cache_free(hpfs_inode_cachep, hpfs_i(inode));
245 }
246 
247 static void hpfs_destroy_inode(struct inode *inode)
248 {
249 	call_rcu(&inode->i_rcu, hpfs_i_callback);
250 }
251 
252 static void init_once(void *foo)
253 {
254 	struct hpfs_inode_info *ei = (struct hpfs_inode_info *) foo;
255 
256 	inode_init_once(&ei->vfs_inode);
257 }
258 
259 static int init_inodecache(void)
260 {
261 	hpfs_inode_cachep = kmem_cache_create("hpfs_inode_cache",
262 					     sizeof(struct hpfs_inode_info),
263 					     0, (SLAB_RECLAIM_ACCOUNT|
264 						SLAB_MEM_SPREAD),
265 					     init_once);
266 	if (hpfs_inode_cachep == NULL)
267 		return -ENOMEM;
268 	return 0;
269 }
270 
271 static void destroy_inodecache(void)
272 {
273 	/*
274 	 * Make sure all delayed rcu free inodes are flushed before we
275 	 * destroy cache.
276 	 */
277 	rcu_barrier();
278 	kmem_cache_destroy(hpfs_inode_cachep);
279 }
280 
281 /*
282  * A tiny parser for option strings, stolen from dosfs.
283  * Stolen again from read-only hpfs.
284  * And updated for table-driven option parsing.
285  */
286 
287 enum {
288 	Opt_help, Opt_uid, Opt_gid, Opt_umask, Opt_case_lower, Opt_case_asis,
289 	Opt_check_none, Opt_check_normal, Opt_check_strict,
290 	Opt_err_cont, Opt_err_ro, Opt_err_panic,
291 	Opt_eas_no, Opt_eas_ro, Opt_eas_rw,
292 	Opt_chkdsk_no, Opt_chkdsk_errors, Opt_chkdsk_always,
293 	Opt_timeshift, Opt_err,
294 };
295 
296 static const match_table_t tokens = {
297 	{Opt_help, "help"},
298 	{Opt_uid, "uid=%u"},
299 	{Opt_gid, "gid=%u"},
300 	{Opt_umask, "umask=%o"},
301 	{Opt_case_lower, "case=lower"},
302 	{Opt_case_asis, "case=asis"},
303 	{Opt_check_none, "check=none"},
304 	{Opt_check_normal, "check=normal"},
305 	{Opt_check_strict, "check=strict"},
306 	{Opt_err_cont, "errors=continue"},
307 	{Opt_err_ro, "errors=remount-ro"},
308 	{Opt_err_panic, "errors=panic"},
309 	{Opt_eas_no, "eas=no"},
310 	{Opt_eas_ro, "eas=ro"},
311 	{Opt_eas_rw, "eas=rw"},
312 	{Opt_chkdsk_no, "chkdsk=no"},
313 	{Opt_chkdsk_errors, "chkdsk=errors"},
314 	{Opt_chkdsk_always, "chkdsk=always"},
315 	{Opt_timeshift, "timeshift=%d"},
316 	{Opt_err, NULL},
317 };
318 
319 static int parse_opts(char *opts, kuid_t *uid, kgid_t *gid, umode_t *umask,
320 		      int *lowercase, int *eas, int *chk, int *errs,
321 		      int *chkdsk, int *timeshift)
322 {
323 	char *p;
324 	int option;
325 
326 	if (!opts)
327 		return 1;
328 
329 	/*pr_info("Parsing opts: '%s'\n",opts);*/
330 
331 	while ((p = strsep(&opts, ",")) != NULL) {
332 		substring_t args[MAX_OPT_ARGS];
333 		int token;
334 		if (!*p)
335 			continue;
336 
337 		token = match_token(p, tokens, args);
338 		switch (token) {
339 		case Opt_help:
340 			return 2;
341 		case Opt_uid:
342 			if (match_int(args, &option))
343 				return 0;
344 			*uid = make_kuid(current_user_ns(), option);
345 			if (!uid_valid(*uid))
346 				return 0;
347 			break;
348 		case Opt_gid:
349 			if (match_int(args, &option))
350 				return 0;
351 			*gid = make_kgid(current_user_ns(), option);
352 			if (!gid_valid(*gid))
353 				return 0;
354 			break;
355 		case Opt_umask:
356 			if (match_octal(args, &option))
357 				return 0;
358 			*umask = option;
359 			break;
360 		case Opt_case_lower:
361 			*lowercase = 1;
362 			break;
363 		case Opt_case_asis:
364 			*lowercase = 0;
365 			break;
366 		case Opt_check_none:
367 			*chk = 0;
368 			break;
369 		case Opt_check_normal:
370 			*chk = 1;
371 			break;
372 		case Opt_check_strict:
373 			*chk = 2;
374 			break;
375 		case Opt_err_cont:
376 			*errs = 0;
377 			break;
378 		case Opt_err_ro:
379 			*errs = 1;
380 			break;
381 		case Opt_err_panic:
382 			*errs = 2;
383 			break;
384 		case Opt_eas_no:
385 			*eas = 0;
386 			break;
387 		case Opt_eas_ro:
388 			*eas = 1;
389 			break;
390 		case Opt_eas_rw:
391 			*eas = 2;
392 			break;
393 		case Opt_chkdsk_no:
394 			*chkdsk = 0;
395 			break;
396 		case Opt_chkdsk_errors:
397 			*chkdsk = 1;
398 			break;
399 		case Opt_chkdsk_always:
400 			*chkdsk = 2;
401 			break;
402 		case Opt_timeshift:
403 		{
404 			int m = 1;
405 			char *rhs = args[0].from;
406 			if (!rhs || !*rhs)
407 				return 0;
408 			if (*rhs == '-') m = -1;
409 			if (*rhs == '+' || *rhs == '-') rhs++;
410 			*timeshift = simple_strtoul(rhs, &rhs, 0) * m;
411 			if (*rhs)
412 				return 0;
413 			break;
414 		}
415 		default:
416 			return 0;
417 		}
418 	}
419 	return 1;
420 }
421 
422 static inline void hpfs_help(void)
423 {
424 	pr_info("\n\
425 HPFS filesystem options:\n\
426       help              do not mount and display this text\n\
427       uid=xxx           set uid of files that don't have uid specified in eas\n\
428       gid=xxx           set gid of files that don't have gid specified in eas\n\
429       umask=xxx         set mode of files that don't have mode specified in eas\n\
430       case=lower        lowercase all files\n\
431       case=asis         do not lowercase files (default)\n\
432       check=none        no fs checks - kernel may crash on corrupted filesystem\n\
433       check=normal      do some checks - it should not crash (default)\n\
434       check=strict      do extra time-consuming checks, used for debugging\n\
435       errors=continue   continue on errors\n\
436       errors=remount-ro remount read-only if errors found (default)\n\
437       errors=panic      panic on errors\n\
438       chkdsk=no         do not mark fs for chkdsking even if there were errors\n\
439       chkdsk=errors     mark fs dirty if errors found (default)\n\
440       chkdsk=always     always mark fs dirty - used for debugging\n\
441       eas=no            ignore extended attributes\n\
442       eas=ro            read but do not write extended attributes\n\
443       eas=rw            r/w eas => enables chmod, chown, mknod, ln -s (default)\n\
444       timeshift=nnn	add nnn seconds to file times\n\
445 \n");
446 }
447 
448 static int hpfs_remount_fs(struct super_block *s, int *flags, char *data)
449 {
450 	kuid_t uid;
451 	kgid_t gid;
452 	umode_t umask;
453 	int lowercase, eas, chk, errs, chkdsk, timeshift;
454 	int o;
455 	struct hpfs_sb_info *sbi = hpfs_sb(s);
456 	char *new_opts = kstrdup(data, GFP_KERNEL);
457 
458 	if (!new_opts)
459 		return -ENOMEM;
460 
461 	sync_filesystem(s);
462 
463 	*flags |= MS_NOATIME;
464 
465 	hpfs_lock(s);
466 	uid = sbi->sb_uid; gid = sbi->sb_gid;
467 	umask = 0777 & ~sbi->sb_mode;
468 	lowercase = sbi->sb_lowercase;
469 	eas = sbi->sb_eas; chk = sbi->sb_chk; chkdsk = sbi->sb_chkdsk;
470 	errs = sbi->sb_err; timeshift = sbi->sb_timeshift;
471 
472 	if (!(o = parse_opts(data, &uid, &gid, &umask, &lowercase,
473 	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
474 		pr_err("bad mount options.\n");
475 		goto out_err;
476 	}
477 	if (o == 2) {
478 		hpfs_help();
479 		goto out_err;
480 	}
481 	if (timeshift != sbi->sb_timeshift) {
482 		pr_err("timeshift can't be changed using remount.\n");
483 		goto out_err;
484 	}
485 
486 	unmark_dirty(s);
487 
488 	sbi->sb_uid = uid; sbi->sb_gid = gid;
489 	sbi->sb_mode = 0777 & ~umask;
490 	sbi->sb_lowercase = lowercase;
491 	sbi->sb_eas = eas; sbi->sb_chk = chk; sbi->sb_chkdsk = chkdsk;
492 	sbi->sb_err = errs; sbi->sb_timeshift = timeshift;
493 
494 	if (!(*flags & MS_RDONLY)) mark_dirty(s, 1);
495 
496 	replace_mount_options(s, new_opts);
497 
498 	hpfs_unlock(s);
499 	return 0;
500 
501 out_err:
502 	hpfs_unlock(s);
503 	kfree(new_opts);
504 	return -EINVAL;
505 }
506 
507 /* Super operations */
508 
509 static const struct super_operations hpfs_sops =
510 {
511 	.alloc_inode	= hpfs_alloc_inode,
512 	.destroy_inode	= hpfs_destroy_inode,
513 	.evict_inode	= hpfs_evict_inode,
514 	.put_super	= hpfs_put_super,
515 	.statfs		= hpfs_statfs,
516 	.remount_fs	= hpfs_remount_fs,
517 	.show_options	= generic_show_options,
518 };
519 
520 static int hpfs_fill_super(struct super_block *s, void *options, int silent)
521 {
522 	struct buffer_head *bh0, *bh1, *bh2;
523 	struct hpfs_boot_block *bootblock;
524 	struct hpfs_super_block *superblock;
525 	struct hpfs_spare_block *spareblock;
526 	struct hpfs_sb_info *sbi;
527 	struct inode *root;
528 
529 	kuid_t uid;
530 	kgid_t gid;
531 	umode_t umask;
532 	int lowercase, eas, chk, errs, chkdsk, timeshift;
533 
534 	dnode_secno root_dno;
535 	struct hpfs_dirent *de = NULL;
536 	struct quad_buffer_head qbh;
537 
538 	int o;
539 
540 	save_mount_options(s, options);
541 
542 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
543 	if (!sbi) {
544 		return -ENOMEM;
545 	}
546 	s->s_fs_info = sbi;
547 
548 	mutex_init(&sbi->hpfs_mutex);
549 	hpfs_lock(s);
550 
551 	uid = current_uid();
552 	gid = current_gid();
553 	umask = current_umask();
554 	lowercase = 0;
555 	eas = 2;
556 	chk = 1;
557 	errs = 1;
558 	chkdsk = 1;
559 	timeshift = 0;
560 
561 	if (!(o = parse_opts(options, &uid, &gid, &umask, &lowercase,
562 	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
563 		pr_err("bad mount options.\n");
564 		goto bail0;
565 	}
566 	if (o==2) {
567 		hpfs_help();
568 		goto bail0;
569 	}
570 
571 	/*sbi->sb_mounting = 1;*/
572 	sb_set_blocksize(s, 512);
573 	sbi->sb_fs_size = -1;
574 	if (!(bootblock = hpfs_map_sector(s, 0, &bh0, 0))) goto bail1;
575 	if (!(superblock = hpfs_map_sector(s, 16, &bh1, 1))) goto bail2;
576 	if (!(spareblock = hpfs_map_sector(s, 17, &bh2, 0))) goto bail3;
577 
578 	/* Check magics */
579 	if (/*le16_to_cpu(bootblock->magic) != BB_MAGIC
580 	    ||*/ le32_to_cpu(superblock->magic) != SB_MAGIC
581 	    || le32_to_cpu(spareblock->magic) != SP_MAGIC) {
582 		if (!silent)
583 			pr_err("Bad magic ... probably not HPFS\n");
584 		goto bail4;
585 	}
586 
587 	/* Check version */
588 	if (!(s->s_flags & MS_RDONLY) &&
589 	      superblock->funcversion != 2 && superblock->funcversion != 3) {
590 		pr_err("Bad version %d,%d. Mount readonly to go around\n",
591 			(int)superblock->version, (int)superblock->funcversion);
592 		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");
593 		goto bail4;
594 	}
595 
596 	s->s_flags |= MS_NOATIME;
597 
598 	/* Fill superblock stuff */
599 	s->s_magic = HPFS_SUPER_MAGIC;
600 	s->s_op = &hpfs_sops;
601 	s->s_d_op = &hpfs_dentry_operations;
602 
603 	sbi->sb_root = le32_to_cpu(superblock->root);
604 	sbi->sb_fs_size = le32_to_cpu(superblock->n_sectors);
605 	sbi->sb_bitmaps = le32_to_cpu(superblock->bitmaps);
606 	sbi->sb_dirband_start = le32_to_cpu(superblock->dir_band_start);
607 	sbi->sb_dirband_size = le32_to_cpu(superblock->n_dir_band);
608 	sbi->sb_dmap = le32_to_cpu(superblock->dir_band_bitmap);
609 	sbi->sb_uid = uid;
610 	sbi->sb_gid = gid;
611 	sbi->sb_mode = 0777 & ~umask;
612 	sbi->sb_n_free = -1;
613 	sbi->sb_n_free_dnodes = -1;
614 	sbi->sb_lowercase = lowercase;
615 	sbi->sb_eas = eas;
616 	sbi->sb_chk = chk;
617 	sbi->sb_chkdsk = chkdsk;
618 	sbi->sb_err = errs;
619 	sbi->sb_timeshift = timeshift;
620 	sbi->sb_was_error = 0;
621 	sbi->sb_cp_table = NULL;
622 	sbi->sb_c_bitmap = -1;
623 	sbi->sb_max_fwd_alloc = 0xffffff;
624 
625 	if (sbi->sb_fs_size >= 0x80000000) {
626 		hpfs_error(s, "invalid size in superblock: %08x",
627 			(unsigned)sbi->sb_fs_size);
628 		goto bail4;
629 	}
630 
631 	if (spareblock->n_spares_used)
632 		hpfs_load_hotfix_map(s, spareblock);
633 
634 	/* Load bitmap directory */
635 	if (!(sbi->sb_bmp_dir = hpfs_load_bitmap_directory(s, le32_to_cpu(superblock->bitmaps))))
636 		goto bail4;
637 
638 	/* Check for general fs errors*/
639 	if (spareblock->dirty && !spareblock->old_wrote) {
640 		if (errs == 2) {
641 			pr_err("Improperly stopped, not mounted\n");
642 			goto bail4;
643 		}
644 		hpfs_error(s, "improperly stopped");
645 	}
646 
647 	if (!(s->s_flags & MS_RDONLY)) {
648 		spareblock->dirty = 1;
649 		spareblock->old_wrote = 0;
650 		mark_buffer_dirty(bh2);
651 	}
652 
653 	if (le32_to_cpu(spareblock->n_dnode_spares) != le32_to_cpu(spareblock->n_dnode_spares_free)) {
654 		if (errs >= 2) {
655 			pr_err("Spare dnodes used, try chkdsk\n");
656 			mark_dirty(s, 0);
657 			goto bail4;
658 		}
659 		hpfs_error(s, "warning: spare dnodes used, try chkdsk");
660 		if (errs == 0)
661 			pr_err("Proceeding, but your filesystem could be corrupted if you delete files or directories\n");
662 	}
663 	if (chk) {
664 		unsigned a;
665 		if (le32_to_cpu(superblock->dir_band_end) - le32_to_cpu(superblock->dir_band_start) + 1 != le32_to_cpu(superblock->n_dir_band) ||
666 		    le32_to_cpu(superblock->dir_band_end) < le32_to_cpu(superblock->dir_band_start) || le32_to_cpu(superblock->n_dir_band) > 0x4000) {
667 			hpfs_error(s, "dir band size mismatch: dir_band_start==%08x, dir_band_end==%08x, n_dir_band==%08x",
668 				le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->dir_band_end), le32_to_cpu(superblock->n_dir_band));
669 			goto bail4;
670 		}
671 		a = sbi->sb_dirband_size;
672 		sbi->sb_dirband_size = 0;
673 		if (hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->n_dir_band), "dir_band") ||
674 		    hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_bitmap), 4, "dir_band_bitmap") ||
675 		    hpfs_chk_sectors(s, le32_to_cpu(superblock->bitmaps), 4, "bitmaps")) {
676 			mark_dirty(s, 0);
677 			goto bail4;
678 		}
679 		sbi->sb_dirband_size = a;
680 	} else
681 		pr_err("You really don't want any checks? You are crazy...\n");
682 
683 	/* Load code page table */
684 	if (le32_to_cpu(spareblock->n_code_pages))
685 		if (!(sbi->sb_cp_table = hpfs_load_code_page(s, le32_to_cpu(spareblock->code_page_dir))))
686 			pr_err("code page support is disabled\n");
687 
688 	brelse(bh2);
689 	brelse(bh1);
690 	brelse(bh0);
691 
692 	root = iget_locked(s, sbi->sb_root);
693 	if (!root)
694 		goto bail0;
695 	hpfs_init_inode(root);
696 	hpfs_read_inode(root);
697 	unlock_new_inode(root);
698 	s->s_root = d_make_root(root);
699 	if (!s->s_root)
700 		goto bail0;
701 
702 	/*
703 	 * find the root directory's . pointer & finish filling in the inode
704 	 */
705 
706 	root_dno = hpfs_fnode_dno(s, sbi->sb_root);
707 	if (root_dno)
708 		de = map_dirent(root, root_dno, "\001\001", 2, NULL, &qbh);
709 	if (!de)
710 		hpfs_error(s, "unable to find root dir");
711 	else {
712 		root->i_atime.tv_sec = local_to_gmt(s, le32_to_cpu(de->read_date));
713 		root->i_atime.tv_nsec = 0;
714 		root->i_mtime.tv_sec = local_to_gmt(s, le32_to_cpu(de->write_date));
715 		root->i_mtime.tv_nsec = 0;
716 		root->i_ctime.tv_sec = local_to_gmt(s, le32_to_cpu(de->creation_date));
717 		root->i_ctime.tv_nsec = 0;
718 		hpfs_i(root)->i_ea_size = le32_to_cpu(de->ea_size);
719 		hpfs_i(root)->i_parent_dir = root->i_ino;
720 		if (root->i_size == -1)
721 			root->i_size = 2048;
722 		if (root->i_blocks == -1)
723 			root->i_blocks = 5;
724 		hpfs_brelse4(&qbh);
725 	}
726 	hpfs_unlock(s);
727 	return 0;
728 
729 bail4:	brelse(bh2);
730 bail3:	brelse(bh1);
731 bail2:	brelse(bh0);
732 bail1:
733 bail0:
734 	hpfs_unlock(s);
735 	free_sbi(sbi);
736 	return -EINVAL;
737 }
738 
739 static struct dentry *hpfs_mount(struct file_system_type *fs_type,
740 	int flags, const char *dev_name, void *data)
741 {
742 	return mount_bdev(fs_type, flags, dev_name, data, hpfs_fill_super);
743 }
744 
745 static struct file_system_type hpfs_fs_type = {
746 	.owner		= THIS_MODULE,
747 	.name		= "hpfs",
748 	.mount		= hpfs_mount,
749 	.kill_sb	= kill_block_super,
750 	.fs_flags	= FS_REQUIRES_DEV,
751 };
752 MODULE_ALIAS_FS("hpfs");
753 
754 static int __init init_hpfs_fs(void)
755 {
756 	int err = init_inodecache();
757 	if (err)
758 		goto out1;
759 	err = register_filesystem(&hpfs_fs_type);
760 	if (err)
761 		goto out;
762 	return 0;
763 out:
764 	destroy_inodecache();
765 out1:
766 	return err;
767 }
768 
769 static void __exit exit_hpfs_fs(void)
770 {
771 	unregister_filesystem(&hpfs_fs_type);
772 	destroy_inodecache();
773 }
774 
775 module_init(init_hpfs_fs)
776 module_exit(exit_hpfs_fs)
777 MODULE_LICENSE("GPL");
778