1 // SPDX-License-Identifier: GPL-2.0-only
3 * linux/fs/affs/inode.c
5 * (c) 1996 Hans-Joachim Widmaier - Rewritten
7 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
9 * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
11 * (C) 1991 Linus Torvalds - minix filesystem
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/statfs.h>
17 #include <linux/fs_parser.h>
18 #include <linux/fs_context.h>
19 #include <linux/magic.h>
20 #include <linux/sched.h>
21 #include <linux/cred.h>
22 #include <linux/slab.h>
23 #include <linux/writeback.h>
24 #include <linux/blkdev.h>
25 #include <linux/seq_file.h>
26 #include <linux/iversion.h>
29 static int affs_statfs(struct dentry
*dentry
, struct kstatfs
*buf
);
30 static int affs_show_options(struct seq_file
*m
, struct dentry
*root
);
33 affs_commit_super(struct super_block
*sb
, int wait
)
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
);
40 affs_secs_to_datestamp(ktime_get_real_seconds(), &tail
->disk_change
);
41 affs_fix_checksum(sb
, bh
);
44 mark_buffer_dirty(bh
);
46 sync_dirty_buffer(bh
);
50 affs_put_super(struct super_block
*sb
)
52 struct affs_sb_info
*sbi
= AFFS_SB(sb
);
53 pr_debug("%s()\n", __func__
);
55 cancel_delayed_work_sync(&sbi
->sb_work
);
59 affs_sync_fs(struct super_block
*sb
, int wait
)
61 affs_commit_super(sb
, wait
);
65 static void flush_superblock(struct work_struct
*work
)
67 struct affs_sb_info
*sbi
;
68 struct super_block
*sb
;
70 sbi
= container_of(work
, struct affs_sb_info
, sb_work
.work
);
73 spin_lock(&sbi
->work_lock
);
75 spin_unlock(&sbi
->work_lock
);
77 affs_commit_super(sb
, 1);
80 void affs_mark_sb_dirty(struct super_block
*sb
)
82 struct affs_sb_info
*sbi
= AFFS_SB(sb
);
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
);
94 spin_unlock(&sbi
->work_lock
);
97 static struct kmem_cache
* affs_inode_cachep
;
99 static struct inode
*affs_alloc_inode(struct super_block
*sb
)
101 struct affs_inode_info
*i
;
103 i
= alloc_inode_sb(sb
, affs_inode_cachep
, GFP_KERNEL
);
107 inode_set_iversion(&i
->vfs_inode
, 1);
112 return &i
->vfs_inode
;
115 static void affs_free_inode(struct inode
*inode
)
117 kmem_cache_free(affs_inode_cachep
, AFFS_I(inode
));
120 static void init_once(void *foo
)
122 struct affs_inode_info
*ei
= (struct affs_inode_info
*) foo
;
124 mutex_init(&ei
->i_link_lock
);
125 mutex_init(&ei
->i_ext_lock
);
126 inode_init_once(&ei
->vfs_inode
);
129 static int __init
init_inodecache(void)
131 affs_inode_cachep
= kmem_cache_create("affs_inode_cache",
132 sizeof(struct affs_inode_info
),
133 0, (SLAB_RECLAIM_ACCOUNT
| SLAB_ACCOUNT
),
135 if (affs_inode_cachep
== NULL
)
140 static void destroy_inodecache(void)
143 * Make sure all delayed rcu free inodes are flushed before we
147 kmem_cache_destroy(affs_inode_cachep
);
150 static const struct super_operations affs_sops
= {
151 .alloc_inode
= affs_alloc_inode
,
152 .free_inode
= affs_free_inode
,
153 .write_inode
= affs_write_inode
,
154 .evict_inode
= affs_evict_inode
,
155 .put_super
= affs_put_super
,
156 .sync_fs
= affs_sync_fs
,
157 .statfs
= affs_statfs
,
158 .show_options
= affs_show_options
,
162 Opt_bs
, Opt_mode
, Opt_mufs
, Opt_notruncate
, Opt_prefix
, Opt_protect
,
163 Opt_reserved
, Opt_root
, Opt_setgid
, Opt_setuid
,
164 Opt_verbose
, Opt_volume
, Opt_ignore
,
167 struct affs_context
{
168 kuid_t uid
; /* uid to override */
169 kgid_t gid
; /* gid to override */
170 unsigned int mode
; /* mode to override */
171 unsigned int reserved
; /* Number of reserved blocks */
172 int root_block
; /* FFS root block number */
173 int blocksize
; /* Initial device blksize */
174 char *prefix
; /* Prefix for volumes and assigns */
175 char volume
[32]; /* Vol. prefix for absolute symlinks */
176 unsigned long mount_flags
; /* Options */
179 static const struct fs_parameter_spec affs_param_spec
[] = {
180 fsparam_u32 ("bs", Opt_bs
),
181 fsparam_u32oct ("mode", Opt_mode
),
182 fsparam_flag ("mufs", Opt_mufs
),
183 fsparam_flag ("nofilenametruncate", Opt_notruncate
),
184 fsparam_string ("prefix", Opt_prefix
),
185 fsparam_flag ("protect", Opt_protect
),
186 fsparam_u32 ("reserved", Opt_reserved
),
187 fsparam_u32 ("root", Opt_root
),
188 fsparam_gid ("setgid", Opt_setgid
),
189 fsparam_uid ("setuid", Opt_setuid
),
190 fsparam_flag ("verbose", Opt_verbose
),
191 fsparam_string ("volume", Opt_volume
),
192 fsparam_flag ("grpquota", Opt_ignore
),
193 fsparam_flag ("noquota", Opt_ignore
),
194 fsparam_flag ("quota", Opt_ignore
),
195 fsparam_flag ("usrquota", Opt_ignore
),
199 static int affs_parse_param(struct fs_context
*fc
, struct fs_parameter
*param
)
201 struct affs_context
*ctx
= fc
->fs_private
;
202 struct fs_parse_result result
;
206 opt
= fs_parse(fc
, affs_param_spec
, param
, &result
);
213 if (n
!= 512 && n
!= 1024 && n
!= 2048
215 pr_warn("Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");
221 ctx
->mode
= result
.uint_32
& 0777;
222 affs_set_opt(ctx
->mount_flags
, SF_SETMODE
);
225 affs_set_opt(ctx
->mount_flags
, SF_MUFS
);
228 affs_set_opt(ctx
->mount_flags
, SF_NO_TRUNCATE
);
232 ctx
->prefix
= param
->string
;
233 param
->string
= NULL
;
234 affs_set_opt(ctx
->mount_flags
, SF_PREFIX
);
237 affs_set_opt(ctx
->mount_flags
, SF_IMMUTABLE
);
240 ctx
->reserved
= result
.uint_32
;
243 ctx
->root_block
= result
.uint_32
;
246 ctx
->gid
= result
.gid
;
247 affs_set_opt(ctx
->mount_flags
, SF_SETGID
);
250 ctx
->uid
= result
.uid
;
251 affs_set_opt(ctx
->mount_flags
, SF_SETUID
);
254 affs_set_opt(ctx
->mount_flags
, SF_VERBOSE
);
257 strscpy(ctx
->volume
, param
->string
, 32);
260 /* Silently ignore the quota options */
268 static int affs_show_options(struct seq_file
*m
, struct dentry
*root
)
270 struct super_block
*sb
= root
->d_sb
;
271 struct affs_sb_info
*sbi
= AFFS_SB(sb
);
274 seq_printf(m
, ",bs=%lu", sb
->s_blocksize
);
275 if (affs_test_opt(sbi
->s_flags
, SF_SETMODE
))
276 seq_printf(m
, ",mode=%o", sbi
->s_mode
);
277 if (affs_test_opt(sbi
->s_flags
, SF_MUFS
))
278 seq_puts(m
, ",mufs");
279 if (affs_test_opt(sbi
->s_flags
, SF_NO_TRUNCATE
))
280 seq_puts(m
, ",nofilenametruncate");
281 if (affs_test_opt(sbi
->s_flags
, SF_PREFIX
))
282 seq_printf(m
, ",prefix=%s", sbi
->s_prefix
);
283 if (affs_test_opt(sbi
->s_flags
, SF_IMMUTABLE
))
284 seq_puts(m
, ",protect");
285 if (sbi
->s_reserved
!= 2)
286 seq_printf(m
, ",reserved=%u", sbi
->s_reserved
);
287 if (sbi
->s_root_block
!= (sbi
->s_reserved
+ sbi
->s_partition_size
- 1) / 2)
288 seq_printf(m
, ",root=%u", sbi
->s_root_block
);
289 if (affs_test_opt(sbi
->s_flags
, SF_SETGID
))
290 seq_printf(m
, ",setgid=%u",
291 from_kgid_munged(&init_user_ns
, sbi
->s_gid
));
292 if (affs_test_opt(sbi
->s_flags
, SF_SETUID
))
293 seq_printf(m
, ",setuid=%u",
294 from_kuid_munged(&init_user_ns
, sbi
->s_uid
));
295 if (affs_test_opt(sbi
->s_flags
, SF_VERBOSE
))
296 seq_puts(m
, ",verbose");
297 if (sbi
->s_volume
[0])
298 seq_printf(m
, ",volume=%s", sbi
->s_volume
);
302 /* This function definitely needs to be split up. Some fine day I'll
303 * hopefully have the guts to do so. Until then: sorry for the mess.
306 static int affs_fill_super(struct super_block
*sb
, struct fs_context
*fc
)
308 struct affs_sb_info
*sbi
;
309 struct affs_context
*ctx
= fc
->fs_private
;
310 struct buffer_head
*root_bh
= NULL
;
311 struct buffer_head
*boot_bh
;
312 struct inode
*root_inode
= NULL
;
313 int silent
= fc
->sb_flags
& SB_SILENT
;
318 int tmp_flags
; /* fix remount prototype... */
322 sb
->s_magic
= AFFS_SUPER_MAGIC
;
323 sb
->s_op
= &affs_sops
;
324 sb
->s_flags
|= SB_NODIRATIME
;
326 sb
->s_time_gran
= NSEC_PER_SEC
;
327 sb
->s_time_min
= sys_tz
.tz_minuteswest
* 60 + AFFS_EPOCH_DELTA
;
328 sb
->s_time_max
= 86400LL * U32_MAX
+ 86400 + sb
->s_time_min
;
330 sbi
= kzalloc(sizeof(struct affs_sb_info
), GFP_KERNEL
);
336 mutex_init(&sbi
->s_bmlock
);
337 spin_lock_init(&sbi
->symlink_lock
);
338 spin_lock_init(&sbi
->work_lock
);
339 INIT_DELAYED_WORK(&sbi
->sb_work
, flush_superblock
);
341 sbi
->s_flags
= ctx
->mount_flags
;
342 sbi
->s_mode
= ctx
->mode
;
343 sbi
->s_uid
= ctx
->uid
;
344 sbi
->s_gid
= ctx
->gid
;
345 sbi
->s_reserved
= ctx
->reserved
;
346 sbi
->s_prefix
= ctx
->prefix
;
348 memcpy(sbi
->s_volume
, ctx
->volume
, 32);
350 /* N.B. after this point s_prefix must be released */
352 /* Get the size of the device in 512-byte blocks.
353 * If we later see that the partition uses bigger
354 * blocks, we will have to change it.
357 size
= bdev_nr_sectors(sb
->s_bdev
);
358 pr_debug("initial blocksize=%d, #blocks=%d\n", 512, size
);
360 affs_set_blocksize(sb
, PAGE_SIZE
);
361 /* Try to find root block. Its location depends on the block size. */
363 i
= bdev_logical_block_size(sb
->s_bdev
);
365 blocksize
= ctx
->blocksize
;
368 size
= size
/ (blocksize
/ 512);
371 for (blocksize
= i
; blocksize
<= j
; blocksize
<<= 1, size
>>= 1) {
372 sbi
->s_root_block
= ctx
->root_block
;
373 if (ctx
->root_block
< 0)
374 sbi
->s_root_block
= (ctx
->reserved
+ size
- 1) / 2;
375 pr_debug("setting blocksize to %d\n", blocksize
);
376 affs_set_blocksize(sb
, blocksize
);
377 sbi
->s_partition_size
= size
;
379 /* The root block location that was calculated above is not
380 * correct if the partition size is an odd number of 512-
381 * byte blocks, which will be rounded down to a number of
382 * 1024-byte blocks, and if there were an even number of
383 * reserved blocks. Ideally, all partition checkers should
384 * report the real number of blocks of the real blocksize,
385 * but since this just cannot be done, we have to try to
386 * find the root block anyways. In the above case, it is one
387 * block behind the calculated one. So we check this one, too.
389 for (num_bm
= 0; num_bm
< 2; num_bm
++) {
390 pr_debug("Dev %s, trying root=%u, bs=%d, "
391 "size=%d, reserved=%d\n",
393 sbi
->s_root_block
+ num_bm
,
394 ctx
->blocksize
, size
, ctx
->reserved
);
395 root_bh
= affs_bread(sb
, sbi
->s_root_block
+ num_bm
);
398 if (!affs_checksum_block(sb
, root_bh
) &&
399 be32_to_cpu(AFFS_ROOT_HEAD(root_bh
)->ptype
) == T_SHORT
&&
400 be32_to_cpu(AFFS_ROOT_TAIL(sb
, root_bh
)->stype
) == ST_ROOT
) {
401 sbi
->s_hashsize
= blocksize
/ 4 - 56;
402 sbi
->s_root_block
+= num_bm
;
405 affs_brelse(root_bh
);
410 pr_err("No valid root block on device %s\n", sb
->s_id
);
413 /* N.B. after this point bh must be released */
415 /* Keep super block in cache */
416 sbi
->s_root_bh
= root_bh
;
417 ctx
->root_block
= sbi
->s_root_block
;
419 /* Find out which kind of FS we have */
420 boot_bh
= sb_bread(sb
, 0);
422 pr_err("Cannot read boot block\n");
425 memcpy(sig
, boot_bh
->b_data
, 4);
427 chksum
= be32_to_cpu(*(__be32
*)sig
);
429 /* Dircache filesystems are compatible with non-dircache ones
430 * when reading. As long as they aren't supported, writing is
433 if ((chksum
== FS_DCFFS
|| chksum
== MUFS_DCFFS
|| chksum
== FS_DCOFS
434 || chksum
== MUFS_DCOFS
) && !sb_rdonly(sb
)) {
435 pr_notice("Dircache FS - mounting %s read only\n", sb
->s_id
);
436 sb
->s_flags
|= SB_RDONLY
;
442 affs_set_opt(sbi
->s_flags
, SF_MUFS
);
446 affs_set_opt(sbi
->s_flags
, SF_INTL
);
449 affs_set_opt(sbi
->s_flags
, SF_MUFS
);
454 affs_set_opt(sbi
->s_flags
, SF_MUFS
);
457 affs_set_opt(sbi
->s_flags
, SF_OFS
);
458 sb
->s_flags
|= SB_NOEXEC
;
462 affs_set_opt(sbi
->s_flags
, SF_MUFS
);
466 affs_set_opt(sbi
->s_flags
, SF_INTL
);
467 affs_set_opt(sbi
->s_flags
, SF_OFS
);
468 sb
->s_flags
|= SB_NOEXEC
;
471 pr_err("Unknown filesystem on device %s: %08X\n",
476 if (affs_test_opt(ctx
->mount_flags
, SF_VERBOSE
)) {
477 u8 len
= AFFS_ROOT_TAIL(sb
, root_bh
)->disk_name
[0];
478 pr_notice("Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n",
480 AFFS_ROOT_TAIL(sb
, root_bh
)->disk_name
+ 1,
481 sig
, sig
[3] + '0', blocksize
);
484 sb
->s_flags
|= SB_NODEV
| SB_NOSUID
;
486 sbi
->s_data_blksize
= sb
->s_blocksize
;
487 if (affs_test_opt(sbi
->s_flags
, SF_OFS
))
488 sbi
->s_data_blksize
-= 24;
490 tmp_flags
= sb
->s_flags
;
491 ret
= affs_init_bitmap(sb
, &tmp_flags
);
494 sb
->s_flags
= tmp_flags
;
496 /* set up enough so that it can read an inode */
498 root_inode
= affs_iget(sb
, ctx
->root_block
);
499 if (IS_ERR(root_inode
))
500 return PTR_ERR(root_inode
);
502 if (affs_test_opt(AFFS_SB(sb
)->s_flags
, SF_INTL
))
503 sb
->s_d_op
= &affs_intl_dentry_operations
;
505 sb
->s_d_op
= &affs_dentry_operations
;
507 sb
->s_root
= d_make_root(root_inode
);
509 pr_err("AFFS: Get root inode failed\n");
513 sb
->s_export_op
= &affs_export_ops
;
514 pr_debug("s_flags=%lX\n", sb
->s_flags
);
518 static int affs_reconfigure(struct fs_context
*fc
)
520 struct super_block
*sb
= fc
->root
->d_sb
;
521 struct affs_context
*ctx
= fc
->fs_private
;
522 struct affs_sb_info
*sbi
= AFFS_SB(sb
);
526 fc
->sb_flags
|= SB_NODIRATIME
;
528 flush_delayed_work(&sbi
->sb_work
);
531 * NB: Historically, only mount_flags, mode, uid, gic, prefix,
532 * and volume are accepted during remount.
534 sbi
->s_flags
= ctx
->mount_flags
;
535 sbi
->s_mode
= ctx
->mode
;
536 sbi
->s_uid
= ctx
->uid
;
537 sbi
->s_gid
= ctx
->gid
;
538 /* protect against readers */
539 spin_lock(&sbi
->symlink_lock
);
541 kfree(sbi
->s_prefix
);
542 sbi
->s_prefix
= ctx
->prefix
;
545 memcpy(sbi
->s_volume
, ctx
->volume
, 32);
546 spin_unlock(&sbi
->symlink_lock
);
548 if ((bool)(fc
->sb_flags
& SB_RDONLY
) == sb_rdonly(sb
))
551 if (fc
->sb_flags
& SB_RDONLY
)
552 affs_free_bitmap(sb
);
554 res
= affs_init_bitmap(sb
, &fc
->sb_flags
);
560 affs_statfs(struct dentry
*dentry
, struct kstatfs
*buf
)
562 struct super_block
*sb
= dentry
->d_sb
;
564 u64 id
= huge_encode_dev(sb
->s_bdev
->bd_dev
);
566 pr_debug("%s() partsize=%d, reserved=%d\n",
567 __func__
, AFFS_SB(sb
)->s_partition_size
,
568 AFFS_SB(sb
)->s_reserved
);
570 free
= affs_count_free_blocks(sb
);
571 buf
->f_type
= AFFS_SUPER_MAGIC
;
572 buf
->f_bsize
= sb
->s_blocksize
;
573 buf
->f_blocks
= AFFS_SB(sb
)->s_partition_size
- AFFS_SB(sb
)->s_reserved
;
575 buf
->f_bavail
= free
;
576 buf
->f_fsid
= u64_to_fsid(id
);
577 buf
->f_namelen
= AFFSNAMEMAX
;
581 static int affs_get_tree(struct fs_context
*fc
)
583 return get_tree_bdev(fc
, affs_fill_super
);
586 static void affs_kill_sb(struct super_block
*sb
)
588 struct affs_sb_info
*sbi
= AFFS_SB(sb
);
589 kill_block_super(sb
);
591 affs_free_bitmap(sb
);
592 affs_brelse(sbi
->s_root_bh
);
593 kfree(sbi
->s_prefix
);
594 mutex_destroy(&sbi
->s_bmlock
);
599 static void affs_free_fc(struct fs_context
*fc
)
601 struct affs_context
*ctx
= fc
->fs_private
;
607 static const struct fs_context_operations affs_context_ops
= {
608 .parse_param
= affs_parse_param
,
609 .get_tree
= affs_get_tree
,
610 .reconfigure
= affs_reconfigure
,
611 .free
= affs_free_fc
,
614 static int affs_init_fs_context(struct fs_context
*fc
)
616 struct affs_context
*ctx
;
618 ctx
= kzalloc(sizeof(struct affs_context
), GFP_KERNEL
);
622 if (fc
->purpose
== FS_CONTEXT_FOR_RECONFIGURE
) {
623 struct super_block
*sb
= fc
->root
->d_sb
;
624 struct affs_sb_info
*sbi
= AFFS_SB(sb
);
627 * NB: historically, no options other than volume were
628 * preserved across a remount unless they were explicitly
631 memcpy(ctx
->volume
, sbi
->s_volume
, 32);
633 ctx
->uid
= current_uid();
634 ctx
->gid
= current_gid();
636 ctx
->root_block
= -1;
638 ctx
->volume
[0] = ':';
641 fc
->ops
= &affs_context_ops
;
642 fc
->fs_private
= ctx
;
647 static struct file_system_type affs_fs_type
= {
648 .owner
= THIS_MODULE
,
650 .kill_sb
= affs_kill_sb
,
651 .fs_flags
= FS_REQUIRES_DEV
,
652 .init_fs_context
= affs_init_fs_context
,
653 .parameters
= affs_param_spec
,
655 MODULE_ALIAS_FS("affs");
657 static int __init
init_affs_fs(void)
659 int err
= init_inodecache();
662 err
= register_filesystem(&affs_fs_type
);
667 destroy_inodecache();
672 static void __exit
exit_affs_fs(void)
674 unregister_filesystem(&affs_fs_type
);
675 destroy_inodecache();
678 MODULE_DESCRIPTION("Amiga filesystem support for Linux");
679 MODULE_LICENSE("GPL");
681 module_init(init_affs_fs
)
682 module_exit(exit_affs_fs
)