xref: /openbmc/linux/fs/affs/super.c (revision f87deada)
1 /*
2  *  linux/fs/affs/inode.c
3  *
4  *  (c) 1996  Hans-Joachim Widmaier - Rewritten
5  *
6  *  (C) 1993  Ray Burr - Modified for Amiga FFS filesystem.
7  *
8  *  (C) 1992  Eric Youngdale Modified for ISO 9660 filesystem.
9  *
10  *  (C) 1991  Linus Torvalds - minix filesystem
11  */
12 
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/statfs.h>
16 #include <linux/parser.h>
17 #include <linux/magic.h>
18 #include <linux/sched.h>
19 #include <linux/cred.h>
20 #include <linux/slab.h>
21 #include <linux/writeback.h>
22 #include <linux/blkdev.h>
23 #include <linux/seq_file.h>
24 #include <linux/iversion.h>
25 #include "affs.h"
26 
27 static int affs_statfs(struct dentry *dentry, struct kstatfs *buf);
28 static int affs_show_options(struct seq_file *m, struct dentry *root);
29 static int affs_remount (struct super_block *sb, int *flags, char *data);
30 
31 static void
32 affs_commit_super(struct super_block *sb, int wait)
33 {
34 	struct affs_sb_info *sbi = AFFS_SB(sb);
35 	struct buffer_head *bh = sbi->s_root_bh;
36 	struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh);
37 
38 	lock_buffer(bh);
39 	affs_secs_to_datestamp(ktime_get_real_seconds(), &tail->disk_change);
40 	affs_fix_checksum(sb, bh);
41 	unlock_buffer(bh);
42 
43 	mark_buffer_dirty(bh);
44 	if (wait)
45 		sync_dirty_buffer(bh);
46 }
47 
48 static void
49 affs_put_super(struct super_block *sb)
50 {
51 	struct affs_sb_info *sbi = AFFS_SB(sb);
52 	pr_debug("%s()\n", __func__);
53 
54 	cancel_delayed_work_sync(&sbi->sb_work);
55 }
56 
57 static int
58 affs_sync_fs(struct super_block *sb, int wait)
59 {
60 	affs_commit_super(sb, wait);
61 	return 0;
62 }
63 
64 static void flush_superblock(struct work_struct *work)
65 {
66 	struct affs_sb_info *sbi;
67 	struct super_block *sb;
68 
69 	sbi = container_of(work, struct affs_sb_info, sb_work.work);
70 	sb = sbi->sb;
71 
72 	spin_lock(&sbi->work_lock);
73 	sbi->work_queued = 0;
74 	spin_unlock(&sbi->work_lock);
75 
76 	affs_commit_super(sb, 1);
77 }
78 
79 void affs_mark_sb_dirty(struct super_block *sb)
80 {
81 	struct affs_sb_info *sbi = AFFS_SB(sb);
82 	unsigned long delay;
83 
84 	if (sb_rdonly(sb))
85 	       return;
86 
87 	spin_lock(&sbi->work_lock);
88 	if (!sbi->work_queued) {
89 	       delay = msecs_to_jiffies(dirty_writeback_interval * 10);
90 	       queue_delayed_work(system_long_wq, &sbi->sb_work, delay);
91 	       sbi->work_queued = 1;
92 	}
93 	spin_unlock(&sbi->work_lock);
94 }
95 
96 static struct kmem_cache * affs_inode_cachep;
97 
98 static struct inode *affs_alloc_inode(struct super_block *sb)
99 {
100 	struct affs_inode_info *i;
101 
102 	i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL);
103 	if (!i)
104 		return NULL;
105 
106 	inode_set_iversion(&i->vfs_inode, 1);
107 	i->i_lc = NULL;
108 	i->i_ext_bh = NULL;
109 	i->i_pa_cnt = 0;
110 
111 	return &i->vfs_inode;
112 }
113 
114 static void affs_i_callback(struct rcu_head *head)
115 {
116 	struct inode *inode = container_of(head, struct inode, i_rcu);
117 	kmem_cache_free(affs_inode_cachep, AFFS_I(inode));
118 }
119 
120 static void affs_destroy_inode(struct inode *inode)
121 {
122 	call_rcu(&inode->i_rcu, affs_i_callback);
123 }
124 
125 static void init_once(void *foo)
126 {
127 	struct affs_inode_info *ei = (struct affs_inode_info *) foo;
128 
129 	sema_init(&ei->i_link_lock, 1);
130 	sema_init(&ei->i_ext_lock, 1);
131 	inode_init_once(&ei->vfs_inode);
132 }
133 
134 static int __init init_inodecache(void)
135 {
136 	affs_inode_cachep = kmem_cache_create("affs_inode_cache",
137 					     sizeof(struct affs_inode_info),
138 					     0, (SLAB_RECLAIM_ACCOUNT|
139 						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
140 					     init_once);
141 	if (affs_inode_cachep == NULL)
142 		return -ENOMEM;
143 	return 0;
144 }
145 
146 static void destroy_inodecache(void)
147 {
148 	/*
149 	 * Make sure all delayed rcu free inodes are flushed before we
150 	 * destroy cache.
151 	 */
152 	rcu_barrier();
153 	kmem_cache_destroy(affs_inode_cachep);
154 }
155 
156 static const struct super_operations affs_sops = {
157 	.alloc_inode	= affs_alloc_inode,
158 	.destroy_inode	= affs_destroy_inode,
159 	.write_inode	= affs_write_inode,
160 	.evict_inode	= affs_evict_inode,
161 	.put_super	= affs_put_super,
162 	.sync_fs	= affs_sync_fs,
163 	.statfs		= affs_statfs,
164 	.remount_fs	= affs_remount,
165 	.show_options	= affs_show_options,
166 };
167 
168 enum {
169 	Opt_bs, Opt_mode, Opt_mufs, Opt_notruncate, Opt_prefix, Opt_protect,
170 	Opt_reserved, Opt_root, Opt_setgid, Opt_setuid,
171 	Opt_verbose, Opt_volume, Opt_ignore, Opt_err,
172 };
173 
174 static const match_table_t tokens = {
175 	{Opt_bs, "bs=%u"},
176 	{Opt_mode, "mode=%o"},
177 	{Opt_mufs, "mufs"},
178 	{Opt_notruncate, "nofilenametruncate"},
179 	{Opt_prefix, "prefix=%s"},
180 	{Opt_protect, "protect"},
181 	{Opt_reserved, "reserved=%u"},
182 	{Opt_root, "root=%u"},
183 	{Opt_setgid, "setgid=%u"},
184 	{Opt_setuid, "setuid=%u"},
185 	{Opt_verbose, "verbose"},
186 	{Opt_volume, "volume=%s"},
187 	{Opt_ignore, "grpquota"},
188 	{Opt_ignore, "noquota"},
189 	{Opt_ignore, "quota"},
190 	{Opt_ignore, "usrquota"},
191 	{Opt_err, NULL},
192 };
193 
194 static int
195 parse_options(char *options, kuid_t *uid, kgid_t *gid, int *mode, int *reserved, s32 *root,
196 		int *blocksize, char **prefix, char *volume, unsigned long *mount_opts)
197 {
198 	char *p;
199 	substring_t args[MAX_OPT_ARGS];
200 
201 	/* Fill in defaults */
202 
203 	*uid        = current_uid();
204 	*gid        = current_gid();
205 	*reserved   = 2;
206 	*root       = -1;
207 	*blocksize  = -1;
208 	volume[0]   = ':';
209 	volume[1]   = 0;
210 	*mount_opts = 0;
211 	if (!options)
212 		return 1;
213 
214 	while ((p = strsep(&options, ",")) != NULL) {
215 		int token, n, option;
216 		if (!*p)
217 			continue;
218 
219 		token = match_token(p, tokens, args);
220 		switch (token) {
221 		case Opt_bs:
222 			if (match_int(&args[0], &n))
223 				return 0;
224 			if (n != 512 && n != 1024 && n != 2048
225 			    && n != 4096) {
226 				pr_warn("Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");
227 				return 0;
228 			}
229 			*blocksize = n;
230 			break;
231 		case Opt_mode:
232 			if (match_octal(&args[0], &option))
233 				return 0;
234 			*mode = option & 0777;
235 			affs_set_opt(*mount_opts, SF_SETMODE);
236 			break;
237 		case Opt_mufs:
238 			affs_set_opt(*mount_opts, SF_MUFS);
239 			break;
240 		case Opt_notruncate:
241 			affs_set_opt(*mount_opts, SF_NO_TRUNCATE);
242 			break;
243 		case Opt_prefix:
244 			*prefix = match_strdup(&args[0]);
245 			if (!*prefix)
246 				return 0;
247 			affs_set_opt(*mount_opts, SF_PREFIX);
248 			break;
249 		case Opt_protect:
250 			affs_set_opt(*mount_opts, SF_IMMUTABLE);
251 			break;
252 		case Opt_reserved:
253 			if (match_int(&args[0], reserved))
254 				return 0;
255 			break;
256 		case Opt_root:
257 			if (match_int(&args[0], root))
258 				return 0;
259 			break;
260 		case Opt_setgid:
261 			if (match_int(&args[0], &option))
262 				return 0;
263 			*gid = make_kgid(current_user_ns(), option);
264 			if (!gid_valid(*gid))
265 				return 0;
266 			affs_set_opt(*mount_opts, SF_SETGID);
267 			break;
268 		case Opt_setuid:
269 			if (match_int(&args[0], &option))
270 				return 0;
271 			*uid = make_kuid(current_user_ns(), option);
272 			if (!uid_valid(*uid))
273 				return 0;
274 			affs_set_opt(*mount_opts, SF_SETUID);
275 			break;
276 		case Opt_verbose:
277 			affs_set_opt(*mount_opts, SF_VERBOSE);
278 			break;
279 		case Opt_volume: {
280 			char *vol = match_strdup(&args[0]);
281 			if (!vol)
282 				return 0;
283 			strlcpy(volume, vol, 32);
284 			kfree(vol);
285 			break;
286 		}
287 		case Opt_ignore:
288 		 	/* Silently ignore the quota options */
289 			break;
290 		default:
291 			pr_warn("Unrecognized mount option \"%s\" or missing value\n",
292 				p);
293 			return 0;
294 		}
295 	}
296 	return 1;
297 }
298 
299 static int affs_show_options(struct seq_file *m, struct dentry *root)
300 {
301 	struct super_block *sb = root->d_sb;
302 	struct affs_sb_info *sbi = AFFS_SB(sb);
303 
304 	if (sb->s_blocksize)
305 		seq_printf(m, ",bs=%lu", sb->s_blocksize);
306 	if (affs_test_opt(sbi->s_flags, SF_SETMODE))
307 		seq_printf(m, ",mode=%o", sbi->s_mode);
308 	if (affs_test_opt(sbi->s_flags, SF_MUFS))
309 		seq_puts(m, ",mufs");
310 	if (affs_test_opt(sbi->s_flags, SF_NO_TRUNCATE))
311 		seq_puts(m, ",nofilenametruncate");
312 	if (affs_test_opt(sbi->s_flags, SF_PREFIX))
313 		seq_printf(m, ",prefix=%s", sbi->s_prefix);
314 	if (affs_test_opt(sbi->s_flags, SF_IMMUTABLE))
315 		seq_puts(m, ",protect");
316 	if (sbi->s_reserved != 2)
317 		seq_printf(m, ",reserved=%u", sbi->s_reserved);
318 	if (sbi->s_root_block != (sbi->s_reserved + sbi->s_partition_size - 1) / 2)
319 		seq_printf(m, ",root=%u", sbi->s_root_block);
320 	if (affs_test_opt(sbi->s_flags, SF_SETGID))
321 		seq_printf(m, ",setgid=%u",
322 			   from_kgid_munged(&init_user_ns, sbi->s_gid));
323 	if (affs_test_opt(sbi->s_flags, SF_SETUID))
324 		seq_printf(m, ",setuid=%u",
325 			   from_kuid_munged(&init_user_ns, sbi->s_uid));
326 	if (affs_test_opt(sbi->s_flags, SF_VERBOSE))
327 		seq_puts(m, ",verbose");
328 	if (sbi->s_volume[0])
329 		seq_printf(m, ",volume=%s", sbi->s_volume);
330 	return 0;
331 }
332 
333 /* This function definitely needs to be split up. Some fine day I'll
334  * hopefully have the guts to do so. Until then: sorry for the mess.
335  */
336 
337 static int affs_fill_super(struct super_block *sb, void *data, int silent)
338 {
339 	struct affs_sb_info	*sbi;
340 	struct buffer_head	*root_bh = NULL;
341 	struct buffer_head	*boot_bh;
342 	struct inode		*root_inode = NULL;
343 	s32			 root_block;
344 	int			 size, blocksize;
345 	u32			 chksum;
346 	int			 num_bm;
347 	int			 i, j;
348 	kuid_t			 uid;
349 	kgid_t			 gid;
350 	int			 reserved;
351 	unsigned long		 mount_flags;
352 	int			 tmp_flags;	/* fix remount prototype... */
353 	u8			 sig[4];
354 	int			 ret;
355 
356 	pr_debug("read_super(%s)\n", data ? (const char *)data : "no options");
357 
358 	sb->s_magic             = AFFS_SUPER_MAGIC;
359 	sb->s_op                = &affs_sops;
360 	sb->s_flags |= SB_NODIRATIME;
361 
362 	sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL);
363 	if (!sbi)
364 		return -ENOMEM;
365 
366 	sb->s_fs_info = sbi;
367 	sbi->sb = sb;
368 	mutex_init(&sbi->s_bmlock);
369 	spin_lock_init(&sbi->symlink_lock);
370 	spin_lock_init(&sbi->work_lock);
371 	INIT_DELAYED_WORK(&sbi->sb_work, flush_superblock);
372 
373 	if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block,
374 				&blocksize,&sbi->s_prefix,
375 				sbi->s_volume, &mount_flags)) {
376 		pr_err("Error parsing options\n");
377 		return -EINVAL;
378 	}
379 	/* N.B. after this point s_prefix must be released */
380 
381 	sbi->s_flags   = mount_flags;
382 	sbi->s_mode    = i;
383 	sbi->s_uid     = uid;
384 	sbi->s_gid     = gid;
385 	sbi->s_reserved= reserved;
386 
387 	/* Get the size of the device in 512-byte blocks.
388 	 * If we later see that the partition uses bigger
389 	 * blocks, we will have to change it.
390 	 */
391 
392 	size = i_size_read(sb->s_bdev->bd_inode) >> 9;
393 	pr_debug("initial blocksize=%d, #blocks=%d\n", 512, size);
394 
395 	affs_set_blocksize(sb, PAGE_SIZE);
396 	/* Try to find root block. Its location depends on the block size. */
397 
398 	i = bdev_logical_block_size(sb->s_bdev);
399 	j = PAGE_SIZE;
400 	if (blocksize > 0) {
401 		i = j = blocksize;
402 		size = size / (blocksize / 512);
403 	}
404 
405 	for (blocksize = i; blocksize <= j; blocksize <<= 1, size >>= 1) {
406 		sbi->s_root_block = root_block;
407 		if (root_block < 0)
408 			sbi->s_root_block = (reserved + size - 1) / 2;
409 		pr_debug("setting blocksize to %d\n", blocksize);
410 		affs_set_blocksize(sb, blocksize);
411 		sbi->s_partition_size = size;
412 
413 		/* The root block location that was calculated above is not
414 		 * correct if the partition size is an odd number of 512-
415 		 * byte blocks, which will be rounded down to a number of
416 		 * 1024-byte blocks, and if there were an even number of
417 		 * reserved blocks. Ideally, all partition checkers should
418 		 * report the real number of blocks of the real blocksize,
419 		 * but since this just cannot be done, we have to try to
420 		 * find the root block anyways. In the above case, it is one
421 		 * block behind the calculated one. So we check this one, too.
422 		 */
423 		for (num_bm = 0; num_bm < 2; num_bm++) {
424 			pr_debug("Dev %s, trying root=%u, bs=%d, "
425 				"size=%d, reserved=%d\n",
426 				sb->s_id,
427 				sbi->s_root_block + num_bm,
428 				blocksize, size, reserved);
429 			root_bh = affs_bread(sb, sbi->s_root_block + num_bm);
430 			if (!root_bh)
431 				continue;
432 			if (!affs_checksum_block(sb, root_bh) &&
433 			    be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT &&
434 			    be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) {
435 				sbi->s_hashsize    = blocksize / 4 - 56;
436 				sbi->s_root_block += num_bm;
437 				goto got_root;
438 			}
439 			affs_brelse(root_bh);
440 			root_bh = NULL;
441 		}
442 	}
443 	if (!silent)
444 		pr_err("No valid root block on device %s\n", sb->s_id);
445 	return -EINVAL;
446 
447 	/* N.B. after this point bh must be released */
448 got_root:
449 	/* Keep super block in cache */
450 	sbi->s_root_bh = root_bh;
451 	root_block = sbi->s_root_block;
452 
453 	/* Find out which kind of FS we have */
454 	boot_bh = sb_bread(sb, 0);
455 	if (!boot_bh) {
456 		pr_err("Cannot read boot block\n");
457 		return -EINVAL;
458 	}
459 	memcpy(sig, boot_bh->b_data, 4);
460 	brelse(boot_bh);
461 	chksum = be32_to_cpu(*(__be32 *)sig);
462 
463 	/* Dircache filesystems are compatible with non-dircache ones
464 	 * when reading. As long as they aren't supported, writing is
465 	 * not recommended.
466 	 */
467 	if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS
468 	     || chksum == MUFS_DCOFS) && !sb_rdonly(sb)) {
469 		pr_notice("Dircache FS - mounting %s read only\n", sb->s_id);
470 		sb->s_flags |= SB_RDONLY;
471 	}
472 	switch (chksum) {
473 	case MUFS_FS:
474 	case MUFS_INTLFFS:
475 	case MUFS_DCFFS:
476 		affs_set_opt(sbi->s_flags, SF_MUFS);
477 		/* fall thru */
478 	case FS_INTLFFS:
479 	case FS_DCFFS:
480 		affs_set_opt(sbi->s_flags, SF_INTL);
481 		break;
482 	case MUFS_FFS:
483 		affs_set_opt(sbi->s_flags, SF_MUFS);
484 		break;
485 	case FS_FFS:
486 		break;
487 	case MUFS_OFS:
488 		affs_set_opt(sbi->s_flags, SF_MUFS);
489 		/* fall thru */
490 	case FS_OFS:
491 		affs_set_opt(sbi->s_flags, SF_OFS);
492 		sb->s_flags |= SB_NOEXEC;
493 		break;
494 	case MUFS_DCOFS:
495 	case MUFS_INTLOFS:
496 		affs_set_opt(sbi->s_flags, SF_MUFS);
497 	case FS_DCOFS:
498 	case FS_INTLOFS:
499 		affs_set_opt(sbi->s_flags, SF_INTL);
500 		affs_set_opt(sbi->s_flags, SF_OFS);
501 		sb->s_flags |= SB_NOEXEC;
502 		break;
503 	default:
504 		pr_err("Unknown filesystem on device %s: %08X\n",
505 		       sb->s_id, chksum);
506 		return -EINVAL;
507 	}
508 
509 	if (affs_test_opt(mount_flags, SF_VERBOSE)) {
510 		u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0];
511 		pr_notice("Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n",
512 			len > 31 ? 31 : len,
513 			AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1,
514 			sig, sig[3] + '0', blocksize);
515 	}
516 
517 	sb->s_flags |= SB_NODEV | SB_NOSUID;
518 
519 	sbi->s_data_blksize = sb->s_blocksize;
520 	if (affs_test_opt(sbi->s_flags, SF_OFS))
521 		sbi->s_data_blksize -= 24;
522 
523 	tmp_flags = sb->s_flags;
524 	ret = affs_init_bitmap(sb, &tmp_flags);
525 	if (ret)
526 		return ret;
527 	sb->s_flags = tmp_flags;
528 
529 	/* set up enough so that it can read an inode */
530 
531 	root_inode = affs_iget(sb, root_block);
532 	if (IS_ERR(root_inode))
533 		return PTR_ERR(root_inode);
534 
535 	if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL))
536 		sb->s_d_op = &affs_intl_dentry_operations;
537 	else
538 		sb->s_d_op = &affs_dentry_operations;
539 
540 	sb->s_root = d_make_root(root_inode);
541 	if (!sb->s_root) {
542 		pr_err("AFFS: Get root inode failed\n");
543 		return -ENOMEM;
544 	}
545 
546 	sb->s_export_op = &affs_export_ops;
547 	pr_debug("s_flags=%lX\n", sb->s_flags);
548 	return 0;
549 }
550 
551 static int
552 affs_remount(struct super_block *sb, int *flags, char *data)
553 {
554 	struct affs_sb_info	*sbi = AFFS_SB(sb);
555 	int			 blocksize;
556 	kuid_t			 uid;
557 	kgid_t			 gid;
558 	int			 mode;
559 	int			 reserved;
560 	int			 root_block;
561 	unsigned long		 mount_flags;
562 	int			 res = 0;
563 	char			*new_opts;
564 	char			 volume[32];
565 	char			*prefix = NULL;
566 
567 	new_opts = kstrdup(data, GFP_KERNEL);
568 	if (data && !new_opts)
569 		return -ENOMEM;
570 
571 	pr_debug("%s(flags=0x%x,opts=\"%s\")\n", __func__, *flags, data);
572 
573 	sync_filesystem(sb);
574 	*flags |= SB_NODIRATIME;
575 
576 	memcpy(volume, sbi->s_volume, 32);
577 	if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block,
578 			   &blocksize, &prefix, volume,
579 			   &mount_flags)) {
580 		kfree(prefix);
581 		kfree(new_opts);
582 		return -EINVAL;
583 	}
584 
585 	flush_delayed_work(&sbi->sb_work);
586 
587 	sbi->s_flags = mount_flags;
588 	sbi->s_mode  = mode;
589 	sbi->s_uid   = uid;
590 	sbi->s_gid   = gid;
591 	/* protect against readers */
592 	spin_lock(&sbi->symlink_lock);
593 	if (prefix) {
594 		kfree(sbi->s_prefix);
595 		sbi->s_prefix = prefix;
596 	}
597 	memcpy(sbi->s_volume, volume, 32);
598 	spin_unlock(&sbi->symlink_lock);
599 
600 	if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
601 		return 0;
602 
603 	if (*flags & SB_RDONLY)
604 		affs_free_bitmap(sb);
605 	else
606 		res = affs_init_bitmap(sb, flags);
607 
608 	return res;
609 }
610 
611 static int
612 affs_statfs(struct dentry *dentry, struct kstatfs *buf)
613 {
614 	struct super_block *sb = dentry->d_sb;
615 	int		 free;
616 	u64		 id = huge_encode_dev(sb->s_bdev->bd_dev);
617 
618 	pr_debug("%s() partsize=%d, reserved=%d\n",
619 		 __func__, AFFS_SB(sb)->s_partition_size,
620 		 AFFS_SB(sb)->s_reserved);
621 
622 	free          = affs_count_free_blocks(sb);
623 	buf->f_type    = AFFS_SUPER_MAGIC;
624 	buf->f_bsize   = sb->s_blocksize;
625 	buf->f_blocks  = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved;
626 	buf->f_bfree   = free;
627 	buf->f_bavail  = free;
628 	buf->f_fsid.val[0] = (u32)id;
629 	buf->f_fsid.val[1] = (u32)(id >> 32);
630 	buf->f_namelen = AFFSNAMEMAX;
631 	return 0;
632 }
633 
634 static struct dentry *affs_mount(struct file_system_type *fs_type,
635 	int flags, const char *dev_name, void *data)
636 {
637 	return mount_bdev(fs_type, flags, dev_name, data, affs_fill_super);
638 }
639 
640 static void affs_kill_sb(struct super_block *sb)
641 {
642 	struct affs_sb_info *sbi = AFFS_SB(sb);
643 	kill_block_super(sb);
644 	if (sbi) {
645 		affs_free_bitmap(sb);
646 		affs_brelse(sbi->s_root_bh);
647 		kfree(sbi->s_prefix);
648 		mutex_destroy(&sbi->s_bmlock);
649 		kfree(sbi);
650 	}
651 }
652 
653 static struct file_system_type affs_fs_type = {
654 	.owner		= THIS_MODULE,
655 	.name		= "affs",
656 	.mount		= affs_mount,
657 	.kill_sb	= affs_kill_sb,
658 	.fs_flags	= FS_REQUIRES_DEV,
659 };
660 MODULE_ALIAS_FS("affs");
661 
662 static int __init init_affs_fs(void)
663 {
664 	int err = init_inodecache();
665 	if (err)
666 		goto out1;
667 	err = register_filesystem(&affs_fs_type);
668 	if (err)
669 		goto out;
670 	return 0;
671 out:
672 	destroy_inodecache();
673 out1:
674 	return err;
675 }
676 
677 static void __exit exit_affs_fs(void)
678 {
679 	unregister_filesystem(&affs_fs_type);
680 	destroy_inodecache();
681 }
682 
683 MODULE_DESCRIPTION("Amiga filesystem support for Linux");
684 MODULE_LICENSE("GPL");
685 
686 module_init(init_affs_fs)
687 module_exit(exit_affs_fs)
688