Linux Audio

Check our new training course

Loading...
v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  linux/fs/affs/inode.c
  4 *
  5 *  (c) 1996  Hans-Joachim Widmaier - Rewritten
  6 *
  7 *  (C) 1993  Ray Burr - Modified for Amiga FFS filesystem.
  8 *
  9 *  (C) 1992  Eric Youngdale Modified for ISO 9660 filesystem.
 10 *
 11 *  (C) 1991  Linus Torvalds - minix filesystem
 12 */
 13
 14#include <linux/module.h>
 15#include <linux/init.h>
 16#include <linux/statfs.h>
 17#include <linux/parser.h>
 18#include <linux/magic.h>
 19#include <linux/sched.h>
 20#include <linux/cred.h>
 21#include <linux/slab.h>
 22#include <linux/writeback.h>
 23#include <linux/blkdev.h>
 24#include <linux/seq_file.h>
 25#include <linux/iversion.h>
 26#include "affs.h"
 27
 
 
 28static int affs_statfs(struct dentry *dentry, struct kstatfs *buf);
 29static int affs_show_options(struct seq_file *m, struct dentry *root);
 30static int affs_remount (struct super_block *sb, int *flags, char *data);
 31
 32static void
 33affs_commit_super(struct super_block *sb, int wait)
 34{
 35	struct affs_sb_info *sbi = AFFS_SB(sb);
 36	struct buffer_head *bh = sbi->s_root_bh;
 37	struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh);
 38
 39	lock_buffer(bh);
 40	affs_secs_to_datestamp(ktime_get_real_seconds(), &tail->disk_change);
 41	affs_fix_checksum(sb, bh);
 42	unlock_buffer(bh);
 43
 44	mark_buffer_dirty(bh);
 45	if (wait)
 46		sync_dirty_buffer(bh);
 47}
 48
 49static void
 50affs_put_super(struct super_block *sb)
 51{
 52	struct affs_sb_info *sbi = AFFS_SB(sb);
 53	pr_debug("%s()\n", __func__);
 54
 55	cancel_delayed_work_sync(&sbi->sb_work);
 56}
 57
 58static int
 59affs_sync_fs(struct super_block *sb, int wait)
 60{
 61	affs_commit_super(sb, wait);
 62	return 0;
 63}
 64
 65static void flush_superblock(struct work_struct *work)
 66{
 67	struct affs_sb_info *sbi;
 68	struct super_block *sb;
 69
 70	sbi = container_of(work, struct affs_sb_info, sb_work.work);
 71	sb = sbi->sb;
 72
 73	spin_lock(&sbi->work_lock);
 74	sbi->work_queued = 0;
 75	spin_unlock(&sbi->work_lock);
 76
 77	affs_commit_super(sb, 1);
 78}
 79
 80void affs_mark_sb_dirty(struct super_block *sb)
 81{
 82	struct affs_sb_info *sbi = AFFS_SB(sb);
 83	unsigned long delay;
 84
 85	if (sb_rdonly(sb))
 86	       return;
 87
 88	spin_lock(&sbi->work_lock);
 89	if (!sbi->work_queued) {
 90	       delay = msecs_to_jiffies(dirty_writeback_interval * 10);
 91	       queue_delayed_work(system_long_wq, &sbi->sb_work, delay);
 92	       sbi->work_queued = 1;
 93	}
 94	spin_unlock(&sbi->work_lock);
 95}
 96
 97static struct kmem_cache * affs_inode_cachep;
 98
 99static struct inode *affs_alloc_inode(struct super_block *sb)
100{
101	struct affs_inode_info *i;
102
103	i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL);
104	if (!i)
105		return NULL;
106
107	inode_set_iversion(&i->vfs_inode, 1);
108	i->i_lc = NULL;
109	i->i_ext_bh = NULL;
110	i->i_pa_cnt = 0;
111
112	return &i->vfs_inode;
113}
114
115static void affs_free_inode(struct inode *inode)
116{
 
117	kmem_cache_free(affs_inode_cachep, AFFS_I(inode));
118}
119
 
 
 
 
 
120static void init_once(void *foo)
121{
122	struct affs_inode_info *ei = (struct affs_inode_info *) foo;
123
124	sema_init(&ei->i_link_lock, 1);
125	sema_init(&ei->i_ext_lock, 1);
126	inode_init_once(&ei->vfs_inode);
127}
128
129static int __init init_inodecache(void)
130{
131	affs_inode_cachep = kmem_cache_create("affs_inode_cache",
132					     sizeof(struct affs_inode_info),
133					     0, (SLAB_RECLAIM_ACCOUNT|
134						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
135					     init_once);
136	if (affs_inode_cachep == NULL)
137		return -ENOMEM;
138	return 0;
139}
140
141static void destroy_inodecache(void)
142{
143	/*
144	 * Make sure all delayed rcu free inodes are flushed before we
145	 * destroy cache.
146	 */
147	rcu_barrier();
148	kmem_cache_destroy(affs_inode_cachep);
149}
150
151static const struct super_operations affs_sops = {
152	.alloc_inode	= affs_alloc_inode,
153	.free_inode	= affs_free_inode,
154	.write_inode	= affs_write_inode,
155	.evict_inode	= affs_evict_inode,
156	.put_super	= affs_put_super,
157	.sync_fs	= affs_sync_fs,
158	.statfs		= affs_statfs,
159	.remount_fs	= affs_remount,
160	.show_options	= affs_show_options,
161};
162
163enum {
164	Opt_bs, Opt_mode, Opt_mufs, Opt_notruncate, Opt_prefix, Opt_protect,
165	Opt_reserved, Opt_root, Opt_setgid, Opt_setuid,
166	Opt_verbose, Opt_volume, Opt_ignore, Opt_err,
167};
168
169static const match_table_t tokens = {
170	{Opt_bs, "bs=%u"},
171	{Opt_mode, "mode=%o"},
172	{Opt_mufs, "mufs"},
173	{Opt_notruncate, "nofilenametruncate"},
174	{Opt_prefix, "prefix=%s"},
175	{Opt_protect, "protect"},
176	{Opt_reserved, "reserved=%u"},
177	{Opt_root, "root=%u"},
178	{Opt_setgid, "setgid=%u"},
179	{Opt_setuid, "setuid=%u"},
180	{Opt_verbose, "verbose"},
181	{Opt_volume, "volume=%s"},
182	{Opt_ignore, "grpquota"},
183	{Opt_ignore, "noquota"},
184	{Opt_ignore, "quota"},
185	{Opt_ignore, "usrquota"},
186	{Opt_err, NULL},
187};
188
189static int
190parse_options(char *options, kuid_t *uid, kgid_t *gid, int *mode, int *reserved, s32 *root,
191		int *blocksize, char **prefix, char *volume, unsigned long *mount_opts)
192{
193	char *p;
194	substring_t args[MAX_OPT_ARGS];
195
196	/* Fill in defaults */
197
198	*uid        = current_uid();
199	*gid        = current_gid();
200	*reserved   = 2;
201	*root       = -1;
202	*blocksize  = -1;
203	volume[0]   = ':';
204	volume[1]   = 0;
205	*mount_opts = 0;
206	if (!options)
207		return 1;
208
209	while ((p = strsep(&options, ",")) != NULL) {
210		int token, n, option;
211		if (!*p)
212			continue;
213
214		token = match_token(p, tokens, args);
215		switch (token) {
216		case Opt_bs:
217			if (match_int(&args[0], &n))
218				return 0;
219			if (n != 512 && n != 1024 && n != 2048
220			    && n != 4096) {
221				pr_warn("Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");
222				return 0;
223			}
224			*blocksize = n;
225			break;
226		case Opt_mode:
227			if (match_octal(&args[0], &option))
228				return 0;
229			*mode = option & 0777;
230			affs_set_opt(*mount_opts, SF_SETMODE);
231			break;
232		case Opt_mufs:
233			affs_set_opt(*mount_opts, SF_MUFS);
234			break;
235		case Opt_notruncate:
236			affs_set_opt(*mount_opts, SF_NO_TRUNCATE);
237			break;
238		case Opt_prefix:
239			kfree(*prefix);
240			*prefix = match_strdup(&args[0]);
241			if (!*prefix)
242				return 0;
243			affs_set_opt(*mount_opts, SF_PREFIX);
244			break;
245		case Opt_protect:
246			affs_set_opt(*mount_opts, SF_IMMUTABLE);
247			break;
248		case Opt_reserved:
249			if (match_int(&args[0], reserved))
250				return 0;
251			break;
252		case Opt_root:
253			if (match_int(&args[0], root))
254				return 0;
255			break;
256		case Opt_setgid:
257			if (match_int(&args[0], &option))
258				return 0;
259			*gid = make_kgid(current_user_ns(), option);
260			if (!gid_valid(*gid))
261				return 0;
262			affs_set_opt(*mount_opts, SF_SETGID);
263			break;
264		case Opt_setuid:
265			if (match_int(&args[0], &option))
266				return 0;
267			*uid = make_kuid(current_user_ns(), option);
268			if (!uid_valid(*uid))
269				return 0;
270			affs_set_opt(*mount_opts, SF_SETUID);
271			break;
272		case Opt_verbose:
273			affs_set_opt(*mount_opts, SF_VERBOSE);
274			break;
275		case Opt_volume: {
276			char *vol = match_strdup(&args[0]);
277			if (!vol)
278				return 0;
279			strlcpy(volume, vol, 32);
280			kfree(vol);
281			break;
282		}
283		case Opt_ignore:
284		 	/* Silently ignore the quota options */
285			break;
286		default:
287			pr_warn("Unrecognized mount option \"%s\" or missing value\n",
288				p);
289			return 0;
290		}
291	}
292	return 1;
293}
294
295static int affs_show_options(struct seq_file *m, struct dentry *root)
296{
297	struct super_block *sb = root->d_sb;
298	struct affs_sb_info *sbi = AFFS_SB(sb);
299
300	if (sb->s_blocksize)
301		seq_printf(m, ",bs=%lu", sb->s_blocksize);
302	if (affs_test_opt(sbi->s_flags, SF_SETMODE))
303		seq_printf(m, ",mode=%o", sbi->s_mode);
304	if (affs_test_opt(sbi->s_flags, SF_MUFS))
305		seq_puts(m, ",mufs");
306	if (affs_test_opt(sbi->s_flags, SF_NO_TRUNCATE))
307		seq_puts(m, ",nofilenametruncate");
308	if (affs_test_opt(sbi->s_flags, SF_PREFIX))
309		seq_printf(m, ",prefix=%s", sbi->s_prefix);
310	if (affs_test_opt(sbi->s_flags, SF_IMMUTABLE))
311		seq_puts(m, ",protect");
312	if (sbi->s_reserved != 2)
313		seq_printf(m, ",reserved=%u", sbi->s_reserved);
314	if (sbi->s_root_block != (sbi->s_reserved + sbi->s_partition_size - 1) / 2)
315		seq_printf(m, ",root=%u", sbi->s_root_block);
316	if (affs_test_opt(sbi->s_flags, SF_SETGID))
317		seq_printf(m, ",setgid=%u",
318			   from_kgid_munged(&init_user_ns, sbi->s_gid));
319	if (affs_test_opt(sbi->s_flags, SF_SETUID))
320		seq_printf(m, ",setuid=%u",
321			   from_kuid_munged(&init_user_ns, sbi->s_uid));
322	if (affs_test_opt(sbi->s_flags, SF_VERBOSE))
323		seq_puts(m, ",verbose");
324	if (sbi->s_volume[0])
325		seq_printf(m, ",volume=%s", sbi->s_volume);
326	return 0;
327}
328
329/* This function definitely needs to be split up. Some fine day I'll
330 * hopefully have the guts to do so. Until then: sorry for the mess.
331 */
332
333static int affs_fill_super(struct super_block *sb, void *data, int silent)
334{
335	struct affs_sb_info	*sbi;
336	struct buffer_head	*root_bh = NULL;
337	struct buffer_head	*boot_bh;
338	struct inode		*root_inode = NULL;
339	s32			 root_block;
340	int			 size, blocksize;
341	u32			 chksum;
342	int			 num_bm;
343	int			 i, j;
 
344	kuid_t			 uid;
345	kgid_t			 gid;
346	int			 reserved;
347	unsigned long		 mount_flags;
348	int			 tmp_flags;	/* fix remount prototype... */
349	u8			 sig[4];
350	int			 ret;
351
352	pr_debug("read_super(%s)\n", data ? (const char *)data : "no options");
 
 
353
354	sb->s_magic             = AFFS_SUPER_MAGIC;
355	sb->s_op                = &affs_sops;
356	sb->s_flags |= SB_NODIRATIME;
357
358	sb->s_time_gran = NSEC_PER_SEC;
359	sb->s_time_min = sys_tz.tz_minuteswest * 60 + AFFS_EPOCH_DELTA;
360	sb->s_time_max = 86400LL * U32_MAX + 86400 + sb->s_time_min;
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 */
448got_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 through */
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		/* fall through */
498	case FS_DCOFS:
499	case FS_INTLOFS:
500		affs_set_opt(sbi->s_flags, SF_INTL);
501		affs_set_opt(sbi->s_flags, SF_OFS);
502		sb->s_flags |= SB_NOEXEC;
503		break;
504	default:
505		pr_err("Unknown filesystem on device %s: %08X\n",
506		       sb->s_id, chksum);
507		return -EINVAL;
508	}
509
510	if (affs_test_opt(mount_flags, SF_VERBOSE)) {
511		u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0];
512		pr_notice("Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n",
513			len > 31 ? 31 : len,
514			AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1,
515			sig, sig[3] + '0', blocksize);
516	}
517
518	sb->s_flags |= SB_NODEV | SB_NOSUID;
519
520	sbi->s_data_blksize = sb->s_blocksize;
521	if (affs_test_opt(sbi->s_flags, SF_OFS))
522		sbi->s_data_blksize -= 24;
523
524	tmp_flags = sb->s_flags;
525	ret = affs_init_bitmap(sb, &tmp_flags);
526	if (ret)
527		return ret;
528	sb->s_flags = tmp_flags;
529
530	/* set up enough so that it can read an inode */
531
532	root_inode = affs_iget(sb, root_block);
533	if (IS_ERR(root_inode))
534		return PTR_ERR(root_inode);
535
536	if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL))
537		sb->s_d_op = &affs_intl_dentry_operations;
538	else
539		sb->s_d_op = &affs_dentry_operations;
540
541	sb->s_root = d_make_root(root_inode);
542	if (!sb->s_root) {
543		pr_err("AFFS: Get root inode failed\n");
544		return -ENOMEM;
545	}
546
547	sb->s_export_op = &affs_export_ops;
548	pr_debug("s_flags=%lX\n", sb->s_flags);
549	return 0;
550}
551
552static int
553affs_remount(struct super_block *sb, int *flags, char *data)
554{
555	struct affs_sb_info	*sbi = AFFS_SB(sb);
556	int			 blocksize;
557	kuid_t			 uid;
558	kgid_t			 gid;
559	int			 mode;
560	int			 reserved;
561	int			 root_block;
562	unsigned long		 mount_flags;
563	int			 res = 0;
564	char			*new_opts;
565	char			 volume[32];
566	char			*prefix = NULL;
567
568	new_opts = kstrdup(data, GFP_KERNEL);
569	if (data && !new_opts)
570		return -ENOMEM;
571
572	pr_debug("%s(flags=0x%x,opts=\"%s\")\n", __func__, *flags, data);
573
574	sync_filesystem(sb);
575	*flags |= SB_NODIRATIME;
576
577	memcpy(volume, sbi->s_volume, 32);
578	if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block,
579			   &blocksize, &prefix, volume,
580			   &mount_flags)) {
581		kfree(prefix);
582		kfree(new_opts);
583		return -EINVAL;
584	}
585
586	flush_delayed_work(&sbi->sb_work);
 
587
588	sbi->s_flags = mount_flags;
589	sbi->s_mode  = mode;
590	sbi->s_uid   = uid;
591	sbi->s_gid   = gid;
592	/* protect against readers */
593	spin_lock(&sbi->symlink_lock);
594	if (prefix) {
595		kfree(sbi->s_prefix);
596		sbi->s_prefix = prefix;
597	}
598	memcpy(sbi->s_volume, volume, 32);
599	spin_unlock(&sbi->symlink_lock);
600
601	if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
602		return 0;
603
604	if (*flags & SB_RDONLY)
605		affs_free_bitmap(sb);
606	else
607		res = affs_init_bitmap(sb, flags);
608
609	return res;
610}
611
612static int
613affs_statfs(struct dentry *dentry, struct kstatfs *buf)
614{
615	struct super_block *sb = dentry->d_sb;
616	int		 free;
617	u64		 id = huge_encode_dev(sb->s_bdev->bd_dev);
618
619	pr_debug("%s() partsize=%d, reserved=%d\n",
620		 __func__, AFFS_SB(sb)->s_partition_size,
621		 AFFS_SB(sb)->s_reserved);
622
623	free          = affs_count_free_blocks(sb);
624	buf->f_type    = AFFS_SUPER_MAGIC;
625	buf->f_bsize   = sb->s_blocksize;
626	buf->f_blocks  = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved;
627	buf->f_bfree   = free;
628	buf->f_bavail  = free;
629	buf->f_fsid.val[0] = (u32)id;
630	buf->f_fsid.val[1] = (u32)(id >> 32);
631	buf->f_namelen = AFFSNAMEMAX;
632	return 0;
633}
634
635static struct dentry *affs_mount(struct file_system_type *fs_type,
636	int flags, const char *dev_name, void *data)
637{
638	return mount_bdev(fs_type, flags, dev_name, data, affs_fill_super);
639}
640
641static void affs_kill_sb(struct super_block *sb)
642{
643	struct affs_sb_info *sbi = AFFS_SB(sb);
644	kill_block_super(sb);
645	if (sbi) {
646		affs_free_bitmap(sb);
647		affs_brelse(sbi->s_root_bh);
648		kfree(sbi->s_prefix);
649		mutex_destroy(&sbi->s_bmlock);
650		kfree(sbi);
651	}
652}
653
654static struct file_system_type affs_fs_type = {
655	.owner		= THIS_MODULE,
656	.name		= "affs",
657	.mount		= affs_mount,
658	.kill_sb	= affs_kill_sb,
659	.fs_flags	= FS_REQUIRES_DEV,
660};
661MODULE_ALIAS_FS("affs");
662
663static int __init init_affs_fs(void)
664{
665	int err = init_inodecache();
666	if (err)
667		goto out1;
668	err = register_filesystem(&affs_fs_type);
669	if (err)
670		goto out;
671	return 0;
672out:
673	destroy_inodecache();
674out1:
675	return err;
676}
677
678static void __exit exit_affs_fs(void)
679{
680	unregister_filesystem(&affs_fs_type);
681	destroy_inodecache();
682}
683
684MODULE_DESCRIPTION("Amiga filesystem support for Linux");
685MODULE_LICENSE("GPL");
686
687module_init(init_affs_fs)
688module_exit(exit_affs_fs)
v3.15
 
  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/slab.h>
 20#include <linux/writeback.h>
 
 
 
 21#include "affs.h"
 22
 23extern struct timezone sys_tz;
 24
 25static int affs_statfs(struct dentry *dentry, struct kstatfs *buf);
 
 26static int affs_remount (struct super_block *sb, int *flags, char *data);
 27
 28static void
 29affs_commit_super(struct super_block *sb, int wait)
 30{
 31	struct affs_sb_info *sbi = AFFS_SB(sb);
 32	struct buffer_head *bh = sbi->s_root_bh;
 33	struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh);
 34
 35	lock_buffer(bh);
 36	secs_to_datestamp(get_seconds(), &tail->disk_change);
 37	affs_fix_checksum(sb, bh);
 38	unlock_buffer(bh);
 39
 40	mark_buffer_dirty(bh);
 41	if (wait)
 42		sync_dirty_buffer(bh);
 43}
 44
 45static void
 46affs_put_super(struct super_block *sb)
 47{
 48	struct affs_sb_info *sbi = AFFS_SB(sb);
 49	pr_debug("AFFS: put_super()\n");
 50
 51	cancel_delayed_work_sync(&sbi->sb_work);
 52}
 53
 54static int
 55affs_sync_fs(struct super_block *sb, int wait)
 56{
 57	affs_commit_super(sb, wait);
 58	return 0;
 59}
 60
 61static void flush_superblock(struct work_struct *work)
 62{
 63	struct affs_sb_info *sbi;
 64	struct super_block *sb;
 65
 66	sbi = container_of(work, struct affs_sb_info, sb_work.work);
 67	sb = sbi->sb;
 68
 69	spin_lock(&sbi->work_lock);
 70	sbi->work_queued = 0;
 71	spin_unlock(&sbi->work_lock);
 72
 73	affs_commit_super(sb, 1);
 74}
 75
 76void affs_mark_sb_dirty(struct super_block *sb)
 77{
 78	struct affs_sb_info *sbi = AFFS_SB(sb);
 79	unsigned long delay;
 80
 81	if (sb->s_flags & MS_RDONLY)
 82	       return;
 83
 84	spin_lock(&sbi->work_lock);
 85	if (!sbi->work_queued) {
 86	       delay = msecs_to_jiffies(dirty_writeback_interval * 10);
 87	       queue_delayed_work(system_long_wq, &sbi->sb_work, delay);
 88	       sbi->work_queued = 1;
 89	}
 90	spin_unlock(&sbi->work_lock);
 91}
 92
 93static struct kmem_cache * affs_inode_cachep;
 94
 95static struct inode *affs_alloc_inode(struct super_block *sb)
 96{
 97	struct affs_inode_info *i;
 98
 99	i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL);
100	if (!i)
101		return NULL;
102
103	i->vfs_inode.i_version = 1;
104	i->i_lc = NULL;
105	i->i_ext_bh = NULL;
106	i->i_pa_cnt = 0;
107
108	return &i->vfs_inode;
109}
110
111static void affs_i_callback(struct rcu_head *head)
112{
113	struct inode *inode = container_of(head, struct inode, i_rcu);
114	kmem_cache_free(affs_inode_cachep, AFFS_I(inode));
115}
116
117static void affs_destroy_inode(struct inode *inode)
118{
119	call_rcu(&inode->i_rcu, affs_i_callback);
120}
121
122static void init_once(void *foo)
123{
124	struct affs_inode_info *ei = (struct affs_inode_info *) foo;
125
126	sema_init(&ei->i_link_lock, 1);
127	sema_init(&ei->i_ext_lock, 1);
128	inode_init_once(&ei->vfs_inode);
129}
130
131static int __init init_inodecache(void)
132{
133	affs_inode_cachep = kmem_cache_create("affs_inode_cache",
134					     sizeof(struct affs_inode_info),
135					     0, (SLAB_RECLAIM_ACCOUNT|
136						SLAB_MEM_SPREAD),
137					     init_once);
138	if (affs_inode_cachep == NULL)
139		return -ENOMEM;
140	return 0;
141}
142
143static void destroy_inodecache(void)
144{
145	/*
146	 * Make sure all delayed rcu free inodes are flushed before we
147	 * destroy cache.
148	 */
149	rcu_barrier();
150	kmem_cache_destroy(affs_inode_cachep);
151}
152
153static const struct super_operations affs_sops = {
154	.alloc_inode	= affs_alloc_inode,
155	.destroy_inode	= affs_destroy_inode,
156	.write_inode	= affs_write_inode,
157	.evict_inode	= affs_evict_inode,
158	.put_super	= affs_put_super,
159	.sync_fs	= affs_sync_fs,
160	.statfs		= affs_statfs,
161	.remount_fs	= affs_remount,
162	.show_options	= generic_show_options,
163};
164
165enum {
166	Opt_bs, Opt_mode, Opt_mufs, Opt_notruncate, Opt_prefix, Opt_protect,
167	Opt_reserved, Opt_root, Opt_setgid, Opt_setuid,
168	Opt_verbose, Opt_volume, Opt_ignore, Opt_err,
169};
170
171static const match_table_t tokens = {
172	{Opt_bs, "bs=%u"},
173	{Opt_mode, "mode=%o"},
174	{Opt_mufs, "mufs"},
175	{Opt_notruncate, "nofilenametruncate"},
176	{Opt_prefix, "prefix=%s"},
177	{Opt_protect, "protect"},
178	{Opt_reserved, "reserved=%u"},
179	{Opt_root, "root=%u"},
180	{Opt_setgid, "setgid=%u"},
181	{Opt_setuid, "setuid=%u"},
182	{Opt_verbose, "verbose"},
183	{Opt_volume, "volume=%s"},
184	{Opt_ignore, "grpquota"},
185	{Opt_ignore, "noquota"},
186	{Opt_ignore, "quota"},
187	{Opt_ignore, "usrquota"},
188	{Opt_err, NULL},
189};
190
191static int
192parse_options(char *options, kuid_t *uid, kgid_t *gid, int *mode, int *reserved, s32 *root,
193		int *blocksize, char **prefix, char *volume, unsigned long *mount_opts)
194{
195	char *p;
196	substring_t args[MAX_OPT_ARGS];
197
198	/* Fill in defaults */
199
200	*uid        = current_uid();
201	*gid        = current_gid();
202	*reserved   = 2;
203	*root       = -1;
204	*blocksize  = -1;
205	volume[0]   = ':';
206	volume[1]   = 0;
207	*mount_opts = 0;
208	if (!options)
209		return 1;
210
211	while ((p = strsep(&options, ",")) != NULL) {
212		int token, n, option;
213		if (!*p)
214			continue;
215
216		token = match_token(p, tokens, args);
217		switch (token) {
218		case Opt_bs:
219			if (match_int(&args[0], &n))
220				return 0;
221			if (n != 512 && n != 1024 && n != 2048
222			    && n != 4096) {
223				printk ("AFFS: Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");
224				return 0;
225			}
226			*blocksize = n;
227			break;
228		case Opt_mode:
229			if (match_octal(&args[0], &option))
230				return 0;
231			*mode = option & 0777;
232			*mount_opts |= SF_SETMODE;
233			break;
234		case Opt_mufs:
235			*mount_opts |= SF_MUFS;
236			break;
237		case Opt_notruncate:
238			*mount_opts |= SF_NO_TRUNCATE;
239			break;
240		case Opt_prefix:
 
241			*prefix = match_strdup(&args[0]);
242			if (!*prefix)
243				return 0;
244			*mount_opts |= SF_PREFIX;
245			break;
246		case Opt_protect:
247			*mount_opts |= SF_IMMUTABLE;
248			break;
249		case Opt_reserved:
250			if (match_int(&args[0], reserved))
251				return 0;
252			break;
253		case Opt_root:
254			if (match_int(&args[0], root))
255				return 0;
256			break;
257		case Opt_setgid:
258			if (match_int(&args[0], &option))
259				return 0;
260			*gid = make_kgid(current_user_ns(), option);
261			if (!gid_valid(*gid))
262				return 0;
263			*mount_opts |= SF_SETGID;
264			break;
265		case Opt_setuid:
266			if (match_int(&args[0], &option))
267				return 0;
268			*uid = make_kuid(current_user_ns(), option);
269			if (!uid_valid(*uid))
270				return 0;
271			*mount_opts |= SF_SETUID;
272			break;
273		case Opt_verbose:
274			*mount_opts |= SF_VERBOSE;
275			break;
276		case Opt_volume: {
277			char *vol = match_strdup(&args[0]);
278			if (!vol)
279				return 0;
280			strlcpy(volume, vol, 32);
281			kfree(vol);
282			break;
283		}
284		case Opt_ignore:
285		 	/* Silently ignore the quota options */
286			break;
287		default:
288			printk("AFFS: Unrecognized mount option \"%s\" "
289					"or missing value\n", p);
290			return 0;
291		}
292	}
293	return 1;
294}
295
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
296/* This function definitely needs to be split up. Some fine day I'll
297 * hopefully have the guts to do so. Until then: sorry for the mess.
298 */
299
300static int affs_fill_super(struct super_block *sb, void *data, int silent)
301{
302	struct affs_sb_info	*sbi;
303	struct buffer_head	*root_bh = NULL;
304	struct buffer_head	*boot_bh;
305	struct inode		*root_inode = NULL;
306	s32			 root_block;
307	int			 size, blocksize;
308	u32			 chksum;
309	int			 num_bm;
310	int			 i, j;
311	s32			 key;
312	kuid_t			 uid;
313	kgid_t			 gid;
314	int			 reserved;
315	unsigned long		 mount_flags;
316	int			 tmp_flags;	/* fix remount prototype... */
317	u8			 sig[4];
318	int			 ret;
319
320	save_mount_options(sb, data);
321
322	pr_debug("AFFS: read_super(%s)\n",data ? (const char *)data : "no options");
323
324	sb->s_magic             = AFFS_SUPER_MAGIC;
325	sb->s_op                = &affs_sops;
326	sb->s_flags |= MS_NODIRATIME;
 
 
 
 
327
328	sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL);
329	if (!sbi)
330		return -ENOMEM;
331
332	sb->s_fs_info = sbi;
333	sbi->sb = sb;
334	mutex_init(&sbi->s_bmlock);
335	spin_lock_init(&sbi->symlink_lock);
336	spin_lock_init(&sbi->work_lock);
337	INIT_DELAYED_WORK(&sbi->sb_work, flush_superblock);
338
339	if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block,
340				&blocksize,&sbi->s_prefix,
341				sbi->s_volume, &mount_flags)) {
342		printk(KERN_ERR "AFFS: Error parsing options\n");
343		return -EINVAL;
344	}
345	/* N.B. after this point s_prefix must be released */
346
347	sbi->s_flags   = mount_flags;
348	sbi->s_mode    = i;
349	sbi->s_uid     = uid;
350	sbi->s_gid     = gid;
351	sbi->s_reserved= reserved;
352
353	/* Get the size of the device in 512-byte blocks.
354	 * If we later see that the partition uses bigger
355	 * blocks, we will have to change it.
356	 */
357
358	size = sb->s_bdev->bd_inode->i_size >> 9;
359	pr_debug("AFFS: initial blocksize=%d, #blocks=%d\n", 512, size);
360
361	affs_set_blocksize(sb, PAGE_SIZE);
362	/* Try to find root block. Its location depends on the block size. */
363
364	i = 512;
365	j = 4096;
366	if (blocksize > 0) {
367		i = j = blocksize;
368		size = size / (blocksize / 512);
369	}
370	for (blocksize = i, key = 0; blocksize <= j; blocksize <<= 1, size >>= 1) {
 
371		sbi->s_root_block = root_block;
372		if (root_block < 0)
373			sbi->s_root_block = (reserved + size - 1) / 2;
374		pr_debug("AFFS: setting blocksize to %d\n", blocksize);
375		affs_set_blocksize(sb, blocksize);
376		sbi->s_partition_size = size;
377
378		/* The root block location that was calculated above is not
379		 * correct if the partition size is an odd number of 512-
380		 * byte blocks, which will be rounded down to a number of
381		 * 1024-byte blocks, and if there were an even number of
382		 * reserved blocks. Ideally, all partition checkers should
383		 * report the real number of blocks of the real blocksize,
384		 * but since this just cannot be done, we have to try to
385		 * find the root block anyways. In the above case, it is one
386		 * block behind the calculated one. So we check this one, too.
387		 */
388		for (num_bm = 0; num_bm < 2; num_bm++) {
389			pr_debug("AFFS: Dev %s, trying root=%u, bs=%d, "
390				"size=%d, reserved=%d\n",
391				sb->s_id,
392				sbi->s_root_block + num_bm,
393				blocksize, size, reserved);
394			root_bh = affs_bread(sb, sbi->s_root_block + num_bm);
395			if (!root_bh)
396				continue;
397			if (!affs_checksum_block(sb, root_bh) &&
398			    be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT &&
399			    be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) {
400				sbi->s_hashsize    = blocksize / 4 - 56;
401				sbi->s_root_block += num_bm;
402				key                        = 1;
403				goto got_root;
404			}
405			affs_brelse(root_bh);
406			root_bh = NULL;
407		}
408	}
409	if (!silent)
410		printk(KERN_ERR "AFFS: No valid root block on device %s\n",
411			sb->s_id);
412	return -EINVAL;
413
414	/* N.B. after this point bh must be released */
415got_root:
416	/* Keep super block in cache */
417	sbi->s_root_bh = root_bh;
418	root_block = sbi->s_root_block;
419
420	/* Find out which kind of FS we have */
421	boot_bh = sb_bread(sb, 0);
422	if (!boot_bh) {
423		printk(KERN_ERR "AFFS: Cannot read boot block\n");
424		return -EINVAL;
425	}
426	memcpy(sig, boot_bh->b_data, 4);
427	brelse(boot_bh);
428	chksum = be32_to_cpu(*(__be32 *)sig);
429
430	/* Dircache filesystems are compatible with non-dircache ones
431	 * when reading. As long as they aren't supported, writing is
432	 * not recommended.
433	 */
434	if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS
435	     || chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) {
436		printk(KERN_NOTICE "AFFS: Dircache FS - mounting %s read only\n",
437			sb->s_id);
438		sb->s_flags |= MS_RDONLY;
439	}
440	switch (chksum) {
441		case MUFS_FS:
442		case MUFS_INTLFFS:
443		case MUFS_DCFFS:
444			sbi->s_flags |= SF_MUFS;
445			/* fall thru */
446		case FS_INTLFFS:
447		case FS_DCFFS:
448			sbi->s_flags |= SF_INTL;
449			break;
450		case MUFS_FFS:
451			sbi->s_flags |= SF_MUFS;
452			break;
453		case FS_FFS:
454			break;
455		case MUFS_OFS:
456			sbi->s_flags |= SF_MUFS;
457			/* fall thru */
458		case FS_OFS:
459			sbi->s_flags |= SF_OFS;
460			sb->s_flags |= MS_NOEXEC;
461			break;
462		case MUFS_DCOFS:
463		case MUFS_INTLOFS:
464			sbi->s_flags |= SF_MUFS;
465		case FS_DCOFS:
466		case FS_INTLOFS:
467			sbi->s_flags |= SF_INTL | SF_OFS;
468			sb->s_flags |= MS_NOEXEC;
469			break;
470		default:
471			printk(KERN_ERR "AFFS: Unknown filesystem on device %s: %08X\n",
472				sb->s_id, chksum);
473			return -EINVAL;
 
 
474	}
475
476	if (mount_flags & SF_VERBOSE) {
477		u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0];
478		printk(KERN_NOTICE "AFFS: Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n",
479			len > 31 ? 31 : len,
480			AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1,
481			sig, sig[3] + '0', blocksize);
482	}
483
484	sb->s_flags |= MS_NODEV | MS_NOSUID;
485
486	sbi->s_data_blksize = sb->s_blocksize;
487	if (sbi->s_flags & SF_OFS)
488		sbi->s_data_blksize -= 24;
489
490	tmp_flags = sb->s_flags;
491	ret = affs_init_bitmap(sb, &tmp_flags);
492	if (ret)
493		return ret;
494	sb->s_flags = tmp_flags;
495
496	/* set up enough so that it can read an inode */
497
498	root_inode = affs_iget(sb, root_block);
499	if (IS_ERR(root_inode))
500		return PTR_ERR(root_inode);
501
502	if (AFFS_SB(sb)->s_flags & SF_INTL)
503		sb->s_d_op = &affs_intl_dentry_operations;
504	else
505		sb->s_d_op = &affs_dentry_operations;
506
507	sb->s_root = d_make_root(root_inode);
508	if (!sb->s_root) {
509		printk(KERN_ERR "AFFS: Get root inode failed\n");
510		return -ENOMEM;
511	}
512
513	pr_debug("AFFS: s_flags=%lX\n",sb->s_flags);
 
514	return 0;
515}
516
517static int
518affs_remount(struct super_block *sb, int *flags, char *data)
519{
520	struct affs_sb_info	*sbi = AFFS_SB(sb);
521	int			 blocksize;
522	kuid_t			 uid;
523	kgid_t			 gid;
524	int			 mode;
525	int			 reserved;
526	int			 root_block;
527	unsigned long		 mount_flags;
528	int			 res = 0;
529	char			*new_opts = kstrdup(data, GFP_KERNEL);
530	char			 volume[32];
531	char			*prefix = NULL;
532
533	pr_debug("AFFS: remount(flags=0x%x,opts=\"%s\")\n",*flags,data);
 
 
 
 
534
535	sync_filesystem(sb);
536	*flags |= MS_NODIRATIME;
537
538	memcpy(volume, sbi->s_volume, 32);
539	if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block,
540			   &blocksize, &prefix, volume,
541			   &mount_flags)) {
542		kfree(prefix);
543		kfree(new_opts);
544		return -EINVAL;
545	}
546
547	flush_delayed_work(&sbi->sb_work);
548	replace_mount_options(sb, new_opts);
549
550	sbi->s_flags = mount_flags;
551	sbi->s_mode  = mode;
552	sbi->s_uid   = uid;
553	sbi->s_gid   = gid;
554	/* protect against readers */
555	spin_lock(&sbi->symlink_lock);
556	if (prefix) {
557		kfree(sbi->s_prefix);
558		sbi->s_prefix = prefix;
559	}
560	memcpy(sbi->s_volume, volume, 32);
561	spin_unlock(&sbi->symlink_lock);
562
563	if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
564		return 0;
565
566	if (*flags & MS_RDONLY)
567		affs_free_bitmap(sb);
568	else
569		res = affs_init_bitmap(sb, flags);
570
571	return res;
572}
573
574static int
575affs_statfs(struct dentry *dentry, struct kstatfs *buf)
576{
577	struct super_block *sb = dentry->d_sb;
578	int		 free;
579	u64		 id = huge_encode_dev(sb->s_bdev->bd_dev);
580
581	pr_debug("AFFS: statfs() partsize=%d, reserved=%d\n",AFFS_SB(sb)->s_partition_size,
582	     AFFS_SB(sb)->s_reserved);
 
583
584	free          = affs_count_free_blocks(sb);
585	buf->f_type    = AFFS_SUPER_MAGIC;
586	buf->f_bsize   = sb->s_blocksize;
587	buf->f_blocks  = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved;
588	buf->f_bfree   = free;
589	buf->f_bavail  = free;
590	buf->f_fsid.val[0] = (u32)id;
591	buf->f_fsid.val[1] = (u32)(id >> 32);
592	buf->f_namelen = 30;
593	return 0;
594}
595
596static struct dentry *affs_mount(struct file_system_type *fs_type,
597	int flags, const char *dev_name, void *data)
598{
599	return mount_bdev(fs_type, flags, dev_name, data, affs_fill_super);
600}
601
602static void affs_kill_sb(struct super_block *sb)
603{
604	struct affs_sb_info *sbi = AFFS_SB(sb);
605	kill_block_super(sb);
606	if (sbi) {
607		affs_free_bitmap(sb);
608		affs_brelse(sbi->s_root_bh);
609		kfree(sbi->s_prefix);
 
610		kfree(sbi);
611	}
612}
613
614static struct file_system_type affs_fs_type = {
615	.owner		= THIS_MODULE,
616	.name		= "affs",
617	.mount		= affs_mount,
618	.kill_sb	= affs_kill_sb,
619	.fs_flags	= FS_REQUIRES_DEV,
620};
621MODULE_ALIAS_FS("affs");
622
623static int __init init_affs_fs(void)
624{
625	int err = init_inodecache();
626	if (err)
627		goto out1;
628	err = register_filesystem(&affs_fs_type);
629	if (err)
630		goto out;
631	return 0;
632out:
633	destroy_inodecache();
634out1:
635	return err;
636}
637
638static void __exit exit_affs_fs(void)
639{
640	unregister_filesystem(&affs_fs_type);
641	destroy_inodecache();
642}
643
644MODULE_DESCRIPTION("Amiga filesystem support for Linux");
645MODULE_LICENSE("GPL");
646
647module_init(init_affs_fs)
648module_exit(exit_affs_fs)