xref: /openbmc/linux/fs/hpfs/super.c (revision e3b9f1e8)
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 #include <linux/seq_file.h>
19 
20 /* Mark the filesystem dirty, so that chkdsk checks it when os/2 booted */
21 
22 static void mark_dirty(struct super_block *s, int remount)
23 {
24 	if (hpfs_sb(s)->sb_chkdsk && (remount || !sb_rdonly(s))) {
25 		struct buffer_head *bh;
26 		struct hpfs_spare_block *sb;
27 		if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
28 			sb->dirty = 1;
29 			sb->old_wrote = 0;
30 			mark_buffer_dirty(bh);
31 			sync_dirty_buffer(bh);
32 			brelse(bh);
33 		}
34 	}
35 }
36 
37 /* Mark the filesystem clean (mark it dirty for chkdsk if chkdsk==2 or if there
38    were errors) */
39 
40 static void unmark_dirty(struct super_block *s)
41 {
42 	struct buffer_head *bh;
43 	struct hpfs_spare_block *sb;
44 	if (sb_rdonly(s)) return;
45 	sync_blockdev(s->s_bdev);
46 	if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
47 		sb->dirty = hpfs_sb(s)->sb_chkdsk > 1 - hpfs_sb(s)->sb_was_error;
48 		sb->old_wrote = hpfs_sb(s)->sb_chkdsk >= 2 && !hpfs_sb(s)->sb_was_error;
49 		mark_buffer_dirty(bh);
50 		sync_dirty_buffer(bh);
51 		brelse(bh);
52 	}
53 }
54 
55 /* Filesystem error... */
56 void hpfs_error(struct super_block *s, const char *fmt, ...)
57 {
58 	struct va_format vaf;
59 	va_list args;
60 
61 	va_start(args, fmt);
62 
63 	vaf.fmt = fmt;
64 	vaf.va = &args;
65 
66 	pr_err("filesystem error: %pV", &vaf);
67 
68 	va_end(args);
69 
70 	if (!hpfs_sb(s)->sb_was_error) {
71 		if (hpfs_sb(s)->sb_err == 2) {
72 			pr_cont("; crashing the system because you wanted it\n");
73 			mark_dirty(s, 0);
74 			panic("HPFS panic");
75 		} else if (hpfs_sb(s)->sb_err == 1) {
76 			if (sb_rdonly(s))
77 				pr_cont("; already mounted read-only\n");
78 			else {
79 				pr_cont("; remounting read-only\n");
80 				mark_dirty(s, 0);
81 				s->s_flags |= SB_RDONLY;
82 			}
83 		} else if (sb_rdonly(s))
84 				pr_cont("; going on - but anything won't be destroyed because it's read-only\n");
85 		else
86 			pr_cont("; corrupted filesystem mounted read/write - your computer will explode within 20 seconds ... but you wanted it so!\n");
87 	} else
88 		pr_cont("\n");
89 	hpfs_sb(s)->sb_was_error = 1;
90 }
91 
92 /*
93  * A little trick to detect cycles in many hpfs structures and don't let the
94  * kernel crash on corrupted filesystem. When first called, set c2 to 0.
95  *
96  * BTW. chkdsk doesn't detect cycles correctly. When I had 2 lost directories
97  * nested each in other, chkdsk locked up happilly.
98  */
99 
100 int hpfs_stop_cycles(struct super_block *s, int key, int *c1, int *c2,
101 		char *msg)
102 {
103 	if (*c2 && *c1 == key) {
104 		hpfs_error(s, "cycle detected on key %08x in %s", key, msg);
105 		return 1;
106 	}
107 	(*c2)++;
108 	if (!((*c2 - 1) & *c2)) *c1 = key;
109 	return 0;
110 }
111 
112 static void free_sbi(struct hpfs_sb_info *sbi)
113 {
114 	kfree(sbi->sb_cp_table);
115 	kfree(sbi->sb_bmp_dir);
116 	kfree(sbi);
117 }
118 
119 static void lazy_free_sbi(struct rcu_head *rcu)
120 {
121 	free_sbi(container_of(rcu, struct hpfs_sb_info, rcu));
122 }
123 
124 static void hpfs_put_super(struct super_block *s)
125 {
126 	hpfs_lock(s);
127 	unmark_dirty(s);
128 	hpfs_unlock(s);
129 	call_rcu(&hpfs_sb(s)->rcu, lazy_free_sbi);
130 }
131 
132 static unsigned hpfs_count_one_bitmap(struct super_block *s, secno secno)
133 {
134 	struct quad_buffer_head qbh;
135 	unsigned long *bits;
136 	unsigned count;
137 
138 	bits = hpfs_map_4sectors(s, secno, &qbh, 0);
139 	if (!bits)
140 		return (unsigned)-1;
141 	count = bitmap_weight(bits, 2048 * BITS_PER_BYTE);
142 	hpfs_brelse4(&qbh);
143 	return count;
144 }
145 
146 static unsigned count_bitmaps(struct super_block *s)
147 {
148 	unsigned n, count, n_bands;
149 	n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
150 	count = 0;
151 	for (n = 0; n < COUNT_RD_AHEAD; n++) {
152 		hpfs_prefetch_bitmap(s, n);
153 	}
154 	for (n = 0; n < n_bands; n++) {
155 		unsigned c;
156 		hpfs_prefetch_bitmap(s, n + COUNT_RD_AHEAD);
157 		c = hpfs_count_one_bitmap(s, le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[n]));
158 		if (c != (unsigned)-1)
159 			count += c;
160 	}
161 	return count;
162 }
163 
164 unsigned hpfs_get_free_dnodes(struct super_block *s)
165 {
166 	struct hpfs_sb_info *sbi = hpfs_sb(s);
167 	if (sbi->sb_n_free_dnodes == (unsigned)-1) {
168 		unsigned c = hpfs_count_one_bitmap(s, sbi->sb_dmap);
169 		if (c == (unsigned)-1)
170 			return 0;
171 		sbi->sb_n_free_dnodes = c;
172 	}
173 	return sbi->sb_n_free_dnodes;
174 }
175 
176 static int hpfs_statfs(struct dentry *dentry, struct kstatfs *buf)
177 {
178 	struct super_block *s = dentry->d_sb;
179 	struct hpfs_sb_info *sbi = hpfs_sb(s);
180 	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
181 
182 	hpfs_lock(s);
183 
184 	if (sbi->sb_n_free == (unsigned)-1)
185 		sbi->sb_n_free = count_bitmaps(s);
186 
187 	buf->f_type = s->s_magic;
188 	buf->f_bsize = 512;
189 	buf->f_blocks = sbi->sb_fs_size;
190 	buf->f_bfree = sbi->sb_n_free;
191 	buf->f_bavail = sbi->sb_n_free;
192 	buf->f_files = sbi->sb_dirband_size / 4;
193 	buf->f_ffree = hpfs_get_free_dnodes(s);
194 	buf->f_fsid.val[0] = (u32)id;
195 	buf->f_fsid.val[1] = (u32)(id >> 32);
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 = kmem_cache_alloc(hpfs_inode_cachep, GFP_NOFS);
236 	if (!ei)
237 		return NULL;
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|SLAB_ACCOUNT),
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 
457 	sync_filesystem(s);
458 
459 	*flags |= SB_NOATIME;
460 
461 	hpfs_lock(s);
462 	uid = sbi->sb_uid; gid = sbi->sb_gid;
463 	umask = 0777 & ~sbi->sb_mode;
464 	lowercase = sbi->sb_lowercase;
465 	eas = sbi->sb_eas; chk = sbi->sb_chk; chkdsk = sbi->sb_chkdsk;
466 	errs = sbi->sb_err; timeshift = sbi->sb_timeshift;
467 
468 	if (!(o = parse_opts(data, &uid, &gid, &umask, &lowercase,
469 	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
470 		pr_err("bad mount options.\n");
471 		goto out_err;
472 	}
473 	if (o == 2) {
474 		hpfs_help();
475 		goto out_err;
476 	}
477 	if (timeshift != sbi->sb_timeshift) {
478 		pr_err("timeshift can't be changed using remount.\n");
479 		goto out_err;
480 	}
481 
482 	unmark_dirty(s);
483 
484 	sbi->sb_uid = uid; sbi->sb_gid = gid;
485 	sbi->sb_mode = 0777 & ~umask;
486 	sbi->sb_lowercase = lowercase;
487 	sbi->sb_eas = eas; sbi->sb_chk = chk; sbi->sb_chkdsk = chkdsk;
488 	sbi->sb_err = errs; sbi->sb_timeshift = timeshift;
489 
490 	if (!(*flags & SB_RDONLY)) mark_dirty(s, 1);
491 
492 	hpfs_unlock(s);
493 	return 0;
494 
495 out_err:
496 	hpfs_unlock(s);
497 	return -EINVAL;
498 }
499 
500 static int hpfs_show_options(struct seq_file *seq, struct dentry *root)
501 {
502 	struct hpfs_sb_info *sbi = hpfs_sb(root->d_sb);
503 
504 	seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, sbi->sb_uid));
505 	seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, sbi->sb_gid));
506 	seq_printf(seq, ",umask=%03o", (~sbi->sb_mode & 0777));
507 	if (sbi->sb_lowercase)
508 		seq_printf(seq, ",case=lower");
509 	if (!sbi->sb_chk)
510 		seq_printf(seq, ",check=none");
511 	if (sbi->sb_chk == 2)
512 		seq_printf(seq, ",check=strict");
513 	if (!sbi->sb_err)
514 		seq_printf(seq, ",errors=continue");
515 	if (sbi->sb_err == 2)
516 		seq_printf(seq, ",errors=panic");
517 	if (!sbi->sb_chkdsk)
518 		seq_printf(seq, ",chkdsk=no");
519 	if (sbi->sb_chkdsk == 2)
520 		seq_printf(seq, ",chkdsk=always");
521 	if (!sbi->sb_eas)
522 		seq_printf(seq, ",eas=no");
523 	if (sbi->sb_eas == 1)
524 		seq_printf(seq, ",eas=ro");
525 	if (sbi->sb_timeshift)
526 		seq_printf(seq, ",timeshift=%d", sbi->sb_timeshift);
527 	return 0;
528 }
529 
530 /* Super operations */
531 
532 static const struct super_operations hpfs_sops =
533 {
534 	.alloc_inode	= hpfs_alloc_inode,
535 	.destroy_inode	= hpfs_destroy_inode,
536 	.evict_inode	= hpfs_evict_inode,
537 	.put_super	= hpfs_put_super,
538 	.statfs		= hpfs_statfs,
539 	.remount_fs	= hpfs_remount_fs,
540 	.show_options	= hpfs_show_options,
541 };
542 
543 static int hpfs_fill_super(struct super_block *s, void *options, int silent)
544 {
545 	struct buffer_head *bh0, *bh1, *bh2;
546 	struct hpfs_boot_block *bootblock;
547 	struct hpfs_super_block *superblock;
548 	struct hpfs_spare_block *spareblock;
549 	struct hpfs_sb_info *sbi;
550 	struct inode *root;
551 
552 	kuid_t uid;
553 	kgid_t gid;
554 	umode_t umask;
555 	int lowercase, eas, chk, errs, chkdsk, timeshift;
556 
557 	dnode_secno root_dno;
558 	struct hpfs_dirent *de = NULL;
559 	struct quad_buffer_head qbh;
560 
561 	int o;
562 
563 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
564 	if (!sbi) {
565 		return -ENOMEM;
566 	}
567 	s->s_fs_info = sbi;
568 
569 	mutex_init(&sbi->hpfs_mutex);
570 	hpfs_lock(s);
571 
572 	uid = current_uid();
573 	gid = current_gid();
574 	umask = current_umask();
575 	lowercase = 0;
576 	eas = 2;
577 	chk = 1;
578 	errs = 1;
579 	chkdsk = 1;
580 	timeshift = 0;
581 
582 	if (!(o = parse_opts(options, &uid, &gid, &umask, &lowercase,
583 	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
584 		pr_err("bad mount options.\n");
585 		goto bail0;
586 	}
587 	if (o==2) {
588 		hpfs_help();
589 		goto bail0;
590 	}
591 
592 	/*sbi->sb_mounting = 1;*/
593 	sb_set_blocksize(s, 512);
594 	sbi->sb_fs_size = -1;
595 	if (!(bootblock = hpfs_map_sector(s, 0, &bh0, 0))) goto bail1;
596 	if (!(superblock = hpfs_map_sector(s, 16, &bh1, 1))) goto bail2;
597 	if (!(spareblock = hpfs_map_sector(s, 17, &bh2, 0))) goto bail3;
598 
599 	/* Check magics */
600 	if (/*le16_to_cpu(bootblock->magic) != BB_MAGIC
601 	    ||*/ le32_to_cpu(superblock->magic) != SB_MAGIC
602 	    || le32_to_cpu(spareblock->magic) != SP_MAGIC) {
603 		if (!silent)
604 			pr_err("Bad magic ... probably not HPFS\n");
605 		goto bail4;
606 	}
607 
608 	/* Check version */
609 	if (!sb_rdonly(s) && superblock->funcversion != 2 && superblock->funcversion != 3) {
610 		pr_err("Bad version %d,%d. Mount readonly to go around\n",
611 			(int)superblock->version, (int)superblock->funcversion);
612 		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");
613 		goto bail4;
614 	}
615 
616 	s->s_flags |= SB_NOATIME;
617 
618 	/* Fill superblock stuff */
619 	s->s_magic = HPFS_SUPER_MAGIC;
620 	s->s_op = &hpfs_sops;
621 	s->s_d_op = &hpfs_dentry_operations;
622 
623 	sbi->sb_root = le32_to_cpu(superblock->root);
624 	sbi->sb_fs_size = le32_to_cpu(superblock->n_sectors);
625 	sbi->sb_bitmaps = le32_to_cpu(superblock->bitmaps);
626 	sbi->sb_dirband_start = le32_to_cpu(superblock->dir_band_start);
627 	sbi->sb_dirband_size = le32_to_cpu(superblock->n_dir_band);
628 	sbi->sb_dmap = le32_to_cpu(superblock->dir_band_bitmap);
629 	sbi->sb_uid = uid;
630 	sbi->sb_gid = gid;
631 	sbi->sb_mode = 0777 & ~umask;
632 	sbi->sb_n_free = -1;
633 	sbi->sb_n_free_dnodes = -1;
634 	sbi->sb_lowercase = lowercase;
635 	sbi->sb_eas = eas;
636 	sbi->sb_chk = chk;
637 	sbi->sb_chkdsk = chkdsk;
638 	sbi->sb_err = errs;
639 	sbi->sb_timeshift = timeshift;
640 	sbi->sb_was_error = 0;
641 	sbi->sb_cp_table = NULL;
642 	sbi->sb_c_bitmap = -1;
643 	sbi->sb_max_fwd_alloc = 0xffffff;
644 
645 	if (sbi->sb_fs_size >= 0x80000000) {
646 		hpfs_error(s, "invalid size in superblock: %08x",
647 			(unsigned)sbi->sb_fs_size);
648 		goto bail4;
649 	}
650 
651 	if (spareblock->n_spares_used)
652 		hpfs_load_hotfix_map(s, spareblock);
653 
654 	/* Load bitmap directory */
655 	if (!(sbi->sb_bmp_dir = hpfs_load_bitmap_directory(s, le32_to_cpu(superblock->bitmaps))))
656 		goto bail4;
657 
658 	/* Check for general fs errors*/
659 	if (spareblock->dirty && !spareblock->old_wrote) {
660 		if (errs == 2) {
661 			pr_err("Improperly stopped, not mounted\n");
662 			goto bail4;
663 		}
664 		hpfs_error(s, "improperly stopped");
665 	}
666 
667 	if (!sb_rdonly(s)) {
668 		spareblock->dirty = 1;
669 		spareblock->old_wrote = 0;
670 		mark_buffer_dirty(bh2);
671 	}
672 
673 	if (le32_to_cpu(spareblock->n_dnode_spares) != le32_to_cpu(spareblock->n_dnode_spares_free)) {
674 		if (errs >= 2) {
675 			pr_err("Spare dnodes used, try chkdsk\n");
676 			mark_dirty(s, 0);
677 			goto bail4;
678 		}
679 		hpfs_error(s, "warning: spare dnodes used, try chkdsk");
680 		if (errs == 0)
681 			pr_err("Proceeding, but your filesystem could be corrupted if you delete files or directories\n");
682 	}
683 	if (chk) {
684 		unsigned a;
685 		if (le32_to_cpu(superblock->dir_band_end) - le32_to_cpu(superblock->dir_band_start) + 1 != le32_to_cpu(superblock->n_dir_band) ||
686 		    le32_to_cpu(superblock->dir_band_end) < le32_to_cpu(superblock->dir_band_start) || le32_to_cpu(superblock->n_dir_band) > 0x4000) {
687 			hpfs_error(s, "dir band size mismatch: dir_band_start==%08x, dir_band_end==%08x, n_dir_band==%08x",
688 				le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->dir_band_end), le32_to_cpu(superblock->n_dir_band));
689 			goto bail4;
690 		}
691 		a = sbi->sb_dirband_size;
692 		sbi->sb_dirband_size = 0;
693 		if (hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->n_dir_band), "dir_band") ||
694 		    hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_bitmap), 4, "dir_band_bitmap") ||
695 		    hpfs_chk_sectors(s, le32_to_cpu(superblock->bitmaps), 4, "bitmaps")) {
696 			mark_dirty(s, 0);
697 			goto bail4;
698 		}
699 		sbi->sb_dirband_size = a;
700 	} else
701 		pr_err("You really don't want any checks? You are crazy...\n");
702 
703 	/* Load code page table */
704 	if (le32_to_cpu(spareblock->n_code_pages))
705 		if (!(sbi->sb_cp_table = hpfs_load_code_page(s, le32_to_cpu(spareblock->code_page_dir))))
706 			pr_err("code page support is disabled\n");
707 
708 	brelse(bh2);
709 	brelse(bh1);
710 	brelse(bh0);
711 
712 	root = iget_locked(s, sbi->sb_root);
713 	if (!root)
714 		goto bail0;
715 	hpfs_init_inode(root);
716 	hpfs_read_inode(root);
717 	unlock_new_inode(root);
718 	s->s_root = d_make_root(root);
719 	if (!s->s_root)
720 		goto bail0;
721 
722 	/*
723 	 * find the root directory's . pointer & finish filling in the inode
724 	 */
725 
726 	root_dno = hpfs_fnode_dno(s, sbi->sb_root);
727 	if (root_dno)
728 		de = map_dirent(root, root_dno, "\001\001", 2, NULL, &qbh);
729 	if (!de)
730 		hpfs_error(s, "unable to find root dir");
731 	else {
732 		root->i_atime.tv_sec = local_to_gmt(s, le32_to_cpu(de->read_date));
733 		root->i_atime.tv_nsec = 0;
734 		root->i_mtime.tv_sec = local_to_gmt(s, le32_to_cpu(de->write_date));
735 		root->i_mtime.tv_nsec = 0;
736 		root->i_ctime.tv_sec = local_to_gmt(s, le32_to_cpu(de->creation_date));
737 		root->i_ctime.tv_nsec = 0;
738 		hpfs_i(root)->i_ea_size = le32_to_cpu(de->ea_size);
739 		hpfs_i(root)->i_parent_dir = root->i_ino;
740 		if (root->i_size == -1)
741 			root->i_size = 2048;
742 		if (root->i_blocks == -1)
743 			root->i_blocks = 5;
744 		hpfs_brelse4(&qbh);
745 	}
746 	hpfs_unlock(s);
747 	return 0;
748 
749 bail4:	brelse(bh2);
750 bail3:	brelse(bh1);
751 bail2:	brelse(bh0);
752 bail1:
753 bail0:
754 	hpfs_unlock(s);
755 	free_sbi(sbi);
756 	return -EINVAL;
757 }
758 
759 static struct dentry *hpfs_mount(struct file_system_type *fs_type,
760 	int flags, const char *dev_name, void *data)
761 {
762 	return mount_bdev(fs_type, flags, dev_name, data, hpfs_fill_super);
763 }
764 
765 static struct file_system_type hpfs_fs_type = {
766 	.owner		= THIS_MODULE,
767 	.name		= "hpfs",
768 	.mount		= hpfs_mount,
769 	.kill_sb	= kill_block_super,
770 	.fs_flags	= FS_REQUIRES_DEV,
771 };
772 MODULE_ALIAS_FS("hpfs");
773 
774 static int __init init_hpfs_fs(void)
775 {
776 	int err = init_inodecache();
777 	if (err)
778 		goto out1;
779 	err = register_filesystem(&hpfs_fs_type);
780 	if (err)
781 		goto out;
782 	return 0;
783 out:
784 	destroy_inodecache();
785 out1:
786 	return err;
787 }
788 
789 static void __exit exit_hpfs_fs(void)
790 {
791 	unregister_filesystem(&hpfs_fs_type);
792 	destroy_inodecache();
793 }
794 
795 module_init(init_hpfs_fs)
796 module_exit(exit_hpfs_fs)
797 MODULE_LICENSE("GPL");
798