Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-btrfs-devel.git] / fs / affs / super.c
blobb31507d0f9b961bf0c417a893680f4553a2e4ca3
1 /*
2 * linux/fs/affs/inode.c
4 * (c) 1996 Hans-Joachim Widmaier - Rewritten
6 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
8 * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
10 * (C) 1991 Linus Torvalds - minix filesystem
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 "affs.h"
22 extern struct timezone sys_tz;
24 static int affs_statfs(struct dentry *dentry, struct kstatfs *buf);
25 static int affs_remount (struct super_block *sb, int *flags, char *data);
27 static void
28 affs_commit_super(struct super_block *sb, int wait, int clean)
30 struct affs_sb_info *sbi = AFFS_SB(sb);
31 struct buffer_head *bh = sbi->s_root_bh;
32 struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh);
34 tail->bm_flag = cpu_to_be32(clean);
35 secs_to_datestamp(get_seconds(), &tail->disk_change);
36 affs_fix_checksum(sb, bh);
37 mark_buffer_dirty(bh);
38 if (wait)
39 sync_dirty_buffer(bh);
42 static void
43 affs_put_super(struct super_block *sb)
45 struct affs_sb_info *sbi = AFFS_SB(sb);
46 pr_debug("AFFS: put_super()\n");
48 if (!(sb->s_flags & MS_RDONLY) && sb->s_dirt)
49 affs_commit_super(sb, 1, 1);
51 kfree(sbi->s_prefix);
52 affs_free_bitmap(sb);
53 affs_brelse(sbi->s_root_bh);
54 kfree(sbi);
55 sb->s_fs_info = NULL;
58 static void
59 affs_write_super(struct super_block *sb)
61 lock_super(sb);
62 if (!(sb->s_flags & MS_RDONLY))
63 affs_commit_super(sb, 1, 2);
64 sb->s_dirt = 0;
65 unlock_super(sb);
67 pr_debug("AFFS: write_super() at %lu, clean=2\n", get_seconds());
70 static int
71 affs_sync_fs(struct super_block *sb, int wait)
73 lock_super(sb);
74 affs_commit_super(sb, wait, 2);
75 sb->s_dirt = 0;
76 unlock_super(sb);
77 return 0;
80 static struct kmem_cache * affs_inode_cachep;
82 static struct inode *affs_alloc_inode(struct super_block *sb)
84 struct affs_inode_info *i;
86 i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL);
87 if (!i)
88 return NULL;
90 i->vfs_inode.i_version = 1;
91 i->i_lc = NULL;
92 i->i_ext_bh = NULL;
93 i->i_pa_cnt = 0;
95 return &i->vfs_inode;
98 static void affs_i_callback(struct rcu_head *head)
100 struct inode *inode = container_of(head, struct inode, i_rcu);
101 INIT_LIST_HEAD(&inode->i_dentry);
102 kmem_cache_free(affs_inode_cachep, AFFS_I(inode));
105 static void affs_destroy_inode(struct inode *inode)
107 call_rcu(&inode->i_rcu, affs_i_callback);
110 static void init_once(void *foo)
112 struct affs_inode_info *ei = (struct affs_inode_info *) foo;
114 sema_init(&ei->i_link_lock, 1);
115 sema_init(&ei->i_ext_lock, 1);
116 inode_init_once(&ei->vfs_inode);
119 static int init_inodecache(void)
121 affs_inode_cachep = kmem_cache_create("affs_inode_cache",
122 sizeof(struct affs_inode_info),
123 0, (SLAB_RECLAIM_ACCOUNT|
124 SLAB_MEM_SPREAD),
125 init_once);
126 if (affs_inode_cachep == NULL)
127 return -ENOMEM;
128 return 0;
131 static void destroy_inodecache(void)
133 kmem_cache_destroy(affs_inode_cachep);
136 static const struct super_operations affs_sops = {
137 .alloc_inode = affs_alloc_inode,
138 .destroy_inode = affs_destroy_inode,
139 .write_inode = affs_write_inode,
140 .evict_inode = affs_evict_inode,
141 .put_super = affs_put_super,
142 .write_super = affs_write_super,
143 .sync_fs = affs_sync_fs,
144 .statfs = affs_statfs,
145 .remount_fs = affs_remount,
146 .show_options = generic_show_options,
149 enum {
150 Opt_bs, Opt_mode, Opt_mufs, Opt_prefix, Opt_protect,
151 Opt_reserved, Opt_root, Opt_setgid, Opt_setuid,
152 Opt_verbose, Opt_volume, Opt_ignore, Opt_err,
155 static const match_table_t tokens = {
156 {Opt_bs, "bs=%u"},
157 {Opt_mode, "mode=%o"},
158 {Opt_mufs, "mufs"},
159 {Opt_prefix, "prefix=%s"},
160 {Opt_protect, "protect"},
161 {Opt_reserved, "reserved=%u"},
162 {Opt_root, "root=%u"},
163 {Opt_setgid, "setgid=%u"},
164 {Opt_setuid, "setuid=%u"},
165 {Opt_verbose, "verbose"},
166 {Opt_volume, "volume=%s"},
167 {Opt_ignore, "grpquota"},
168 {Opt_ignore, "noquota"},
169 {Opt_ignore, "quota"},
170 {Opt_ignore, "usrquota"},
171 {Opt_err, NULL},
174 static int
175 parse_options(char *options, uid_t *uid, gid_t *gid, int *mode, int *reserved, s32 *root,
176 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts)
178 char *p;
179 substring_t args[MAX_OPT_ARGS];
181 /* Fill in defaults */
183 *uid = current_uid();
184 *gid = current_gid();
185 *reserved = 2;
186 *root = -1;
187 *blocksize = -1;
188 volume[0] = ':';
189 volume[1] = 0;
190 *mount_opts = 0;
191 if (!options)
192 return 1;
194 while ((p = strsep(&options, ",")) != NULL) {
195 int token, n, option;
196 if (!*p)
197 continue;
199 token = match_token(p, tokens, args);
200 switch (token) {
201 case Opt_bs:
202 if (match_int(&args[0], &n))
203 return 0;
204 if (n != 512 && n != 1024 && n != 2048
205 && n != 4096) {
206 printk ("AFFS: Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");
207 return 0;
209 *blocksize = n;
210 break;
211 case Opt_mode:
212 if (match_octal(&args[0], &option))
213 return 0;
214 *mode = option & 0777;
215 *mount_opts |= SF_SETMODE;
216 break;
217 case Opt_mufs:
218 *mount_opts |= SF_MUFS;
219 break;
220 case Opt_prefix:
221 *prefix = match_strdup(&args[0]);
222 if (!*prefix)
223 return 0;
224 *mount_opts |= SF_PREFIX;
225 break;
226 case Opt_protect:
227 *mount_opts |= SF_IMMUTABLE;
228 break;
229 case Opt_reserved:
230 if (match_int(&args[0], reserved))
231 return 0;
232 break;
233 case Opt_root:
234 if (match_int(&args[0], root))
235 return 0;
236 break;
237 case Opt_setgid:
238 if (match_int(&args[0], &option))
239 return 0;
240 *gid = option;
241 *mount_opts |= SF_SETGID;
242 break;
243 case Opt_setuid:
244 if (match_int(&args[0], &option))
245 return 0;
246 *uid = option;
247 *mount_opts |= SF_SETUID;
248 break;
249 case Opt_verbose:
250 *mount_opts |= SF_VERBOSE;
251 break;
252 case Opt_volume: {
253 char *vol = match_strdup(&args[0]);
254 if (!vol)
255 return 0;
256 strlcpy(volume, vol, 32);
257 kfree(vol);
258 break;
260 case Opt_ignore:
261 /* Silently ignore the quota options */
262 break;
263 default:
264 printk("AFFS: Unrecognized mount option \"%s\" "
265 "or missing value\n", p);
266 return 0;
269 return 1;
272 /* This function definitely needs to be split up. Some fine day I'll
273 * hopefully have the guts to do so. Until then: sorry for the mess.
276 static int affs_fill_super(struct super_block *sb, void *data, int silent)
278 struct affs_sb_info *sbi;
279 struct buffer_head *root_bh = NULL;
280 struct buffer_head *boot_bh;
281 struct inode *root_inode = NULL;
282 s32 root_block;
283 int size, blocksize;
284 u32 chksum;
285 int num_bm;
286 int i, j;
287 s32 key;
288 uid_t uid;
289 gid_t gid;
290 int reserved;
291 unsigned long mount_flags;
292 int tmp_flags; /* fix remount prototype... */
293 u8 sig[4];
294 int ret = -EINVAL;
296 save_mount_options(sb, data);
298 pr_debug("AFFS: read_super(%s)\n",data ? (const char *)data : "no options");
300 sb->s_magic = AFFS_SUPER_MAGIC;
301 sb->s_op = &affs_sops;
302 sb->s_flags |= MS_NODIRATIME;
304 sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL);
305 if (!sbi)
306 return -ENOMEM;
308 sb->s_fs_info = sbi;
309 mutex_init(&sbi->s_bmlock);
310 spin_lock_init(&sbi->symlink_lock);
312 if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block,
313 &blocksize,&sbi->s_prefix,
314 sbi->s_volume, &mount_flags)) {
315 printk(KERN_ERR "AFFS: Error parsing options\n");
316 kfree(sbi->s_prefix);
317 kfree(sbi);
318 return -EINVAL;
320 /* N.B. after this point s_prefix must be released */
322 sbi->s_flags = mount_flags;
323 sbi->s_mode = i;
324 sbi->s_uid = uid;
325 sbi->s_gid = gid;
326 sbi->s_reserved= reserved;
328 /* Get the size of the device in 512-byte blocks.
329 * If we later see that the partition uses bigger
330 * blocks, we will have to change it.
333 size = sb->s_bdev->bd_inode->i_size >> 9;
334 pr_debug("AFFS: initial blocksize=%d, #blocks=%d\n", 512, size);
336 affs_set_blocksize(sb, PAGE_SIZE);
337 /* Try to find root block. Its location depends on the block size. */
339 i = 512;
340 j = 4096;
341 if (blocksize > 0) {
342 i = j = blocksize;
343 size = size / (blocksize / 512);
345 for (blocksize = i, key = 0; blocksize <= j; blocksize <<= 1, size >>= 1) {
346 sbi->s_root_block = root_block;
347 if (root_block < 0)
348 sbi->s_root_block = (reserved + size - 1) / 2;
349 pr_debug("AFFS: setting blocksize to %d\n", blocksize);
350 affs_set_blocksize(sb, blocksize);
351 sbi->s_partition_size = size;
353 /* The root block location that was calculated above is not
354 * correct if the partition size is an odd number of 512-
355 * byte blocks, which will be rounded down to a number of
356 * 1024-byte blocks, and if there were an even number of
357 * reserved blocks. Ideally, all partition checkers should
358 * report the real number of blocks of the real blocksize,
359 * but since this just cannot be done, we have to try to
360 * find the root block anyways. In the above case, it is one
361 * block behind the calculated one. So we check this one, too.
363 for (num_bm = 0; num_bm < 2; num_bm++) {
364 pr_debug("AFFS: Dev %s, trying root=%u, bs=%d, "
365 "size=%d, reserved=%d\n",
366 sb->s_id,
367 sbi->s_root_block + num_bm,
368 blocksize, size, reserved);
369 root_bh = affs_bread(sb, sbi->s_root_block + num_bm);
370 if (!root_bh)
371 continue;
372 if (!affs_checksum_block(sb, root_bh) &&
373 be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT &&
374 be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) {
375 sbi->s_hashsize = blocksize / 4 - 56;
376 sbi->s_root_block += num_bm;
377 key = 1;
378 goto got_root;
380 affs_brelse(root_bh);
381 root_bh = NULL;
384 if (!silent)
385 printk(KERN_ERR "AFFS: No valid root block on device %s\n",
386 sb->s_id);
387 goto out_error;
389 /* N.B. after this point bh must be released */
390 got_root:
391 root_block = sbi->s_root_block;
393 /* Find out which kind of FS we have */
394 boot_bh = sb_bread(sb, 0);
395 if (!boot_bh) {
396 printk(KERN_ERR "AFFS: Cannot read boot block\n");
397 goto out_error;
399 memcpy(sig, boot_bh->b_data, 4);
400 brelse(boot_bh);
401 chksum = be32_to_cpu(*(__be32 *)sig);
403 /* Dircache filesystems are compatible with non-dircache ones
404 * when reading. As long as they aren't supported, writing is
405 * not recommended.
407 if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS
408 || chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) {
409 printk(KERN_NOTICE "AFFS: Dircache FS - mounting %s read only\n",
410 sb->s_id);
411 sb->s_flags |= MS_RDONLY;
413 switch (chksum) {
414 case MUFS_FS:
415 case MUFS_INTLFFS:
416 case MUFS_DCFFS:
417 sbi->s_flags |= SF_MUFS;
418 /* fall thru */
419 case FS_INTLFFS:
420 case FS_DCFFS:
421 sbi->s_flags |= SF_INTL;
422 break;
423 case MUFS_FFS:
424 sbi->s_flags |= SF_MUFS;
425 break;
426 case FS_FFS:
427 break;
428 case MUFS_OFS:
429 sbi->s_flags |= SF_MUFS;
430 /* fall thru */
431 case FS_OFS:
432 sbi->s_flags |= SF_OFS;
433 sb->s_flags |= MS_NOEXEC;
434 break;
435 case MUFS_DCOFS:
436 case MUFS_INTLOFS:
437 sbi->s_flags |= SF_MUFS;
438 case FS_DCOFS:
439 case FS_INTLOFS:
440 sbi->s_flags |= SF_INTL | SF_OFS;
441 sb->s_flags |= MS_NOEXEC;
442 break;
443 default:
444 printk(KERN_ERR "AFFS: Unknown filesystem on device %s: %08X\n",
445 sb->s_id, chksum);
446 goto out_error;
449 if (mount_flags & SF_VERBOSE) {
450 u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0];
451 printk(KERN_NOTICE "AFFS: Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n",
452 len > 31 ? 31 : len,
453 AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1,
454 sig, sig[3] + '0', blocksize);
457 sb->s_flags |= MS_NODEV | MS_NOSUID;
459 sbi->s_data_blksize = sb->s_blocksize;
460 if (sbi->s_flags & SF_OFS)
461 sbi->s_data_blksize -= 24;
463 /* Keep super block in cache */
464 sbi->s_root_bh = root_bh;
465 /* N.B. after this point s_root_bh must be released */
467 tmp_flags = sb->s_flags;
468 if (affs_init_bitmap(sb, &tmp_flags))
469 goto out_error;
470 sb->s_flags = tmp_flags;
472 /* set up enough so that it can read an inode */
474 root_inode = affs_iget(sb, root_block);
475 if (IS_ERR(root_inode)) {
476 ret = PTR_ERR(root_inode);
477 goto out_error_noinode;
480 if (AFFS_SB(sb)->s_flags & SF_INTL)
481 sb->s_d_op = &affs_intl_dentry_operations;
482 else
483 sb->s_d_op = &affs_dentry_operations;
485 sb->s_root = d_alloc_root(root_inode);
486 if (!sb->s_root) {
487 printk(KERN_ERR "AFFS: Get root inode failed\n");
488 goto out_error;
491 pr_debug("AFFS: s_flags=%lX\n",sb->s_flags);
492 return 0;
495 * Begin the cascaded cleanup ...
497 out_error:
498 if (root_inode)
499 iput(root_inode);
500 out_error_noinode:
501 kfree(sbi->s_bitmap);
502 affs_brelse(root_bh);
503 kfree(sbi->s_prefix);
504 kfree(sbi);
505 sb->s_fs_info = NULL;
506 return ret;
509 static int
510 affs_remount(struct super_block *sb, int *flags, char *data)
512 struct affs_sb_info *sbi = AFFS_SB(sb);
513 int blocksize;
514 uid_t uid;
515 gid_t gid;
516 int mode;
517 int reserved;
518 int root_block;
519 unsigned long mount_flags;
520 int res = 0;
521 char *new_opts = kstrdup(data, GFP_KERNEL);
522 char volume[32];
523 char *prefix = NULL;
525 pr_debug("AFFS: remount(flags=0x%x,opts=\"%s\")\n",*flags,data);
527 *flags |= MS_NODIRATIME;
529 memcpy(volume, sbi->s_volume, 32);
530 if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block,
531 &blocksize, &prefix, volume,
532 &mount_flags)) {
533 kfree(prefix);
534 kfree(new_opts);
535 return -EINVAL;
538 replace_mount_options(sb, new_opts);
540 sbi->s_flags = mount_flags;
541 sbi->s_mode = mode;
542 sbi->s_uid = uid;
543 sbi->s_gid = gid;
544 /* protect against readers */
545 spin_lock(&sbi->symlink_lock);
546 if (prefix) {
547 kfree(sbi->s_prefix);
548 sbi->s_prefix = prefix;
550 memcpy(sbi->s_volume, volume, 32);
551 spin_unlock(&sbi->symlink_lock);
553 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
554 return 0;
556 if (*flags & MS_RDONLY) {
557 affs_write_super(sb);
558 affs_free_bitmap(sb);
559 } else
560 res = affs_init_bitmap(sb, flags);
562 return res;
565 static int
566 affs_statfs(struct dentry *dentry, struct kstatfs *buf)
568 struct super_block *sb = dentry->d_sb;
569 int free;
570 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
572 pr_debug("AFFS: statfs() partsize=%d, reserved=%d\n",AFFS_SB(sb)->s_partition_size,
573 AFFS_SB(sb)->s_reserved);
575 free = affs_count_free_blocks(sb);
576 buf->f_type = AFFS_SUPER_MAGIC;
577 buf->f_bsize = sb->s_blocksize;
578 buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved;
579 buf->f_bfree = free;
580 buf->f_bavail = free;
581 buf->f_fsid.val[0] = (u32)id;
582 buf->f_fsid.val[1] = (u32)(id >> 32);
583 buf->f_namelen = 30;
584 return 0;
587 static struct dentry *affs_mount(struct file_system_type *fs_type,
588 int flags, const char *dev_name, void *data)
590 return mount_bdev(fs_type, flags, dev_name, data, affs_fill_super);
593 static struct file_system_type affs_fs_type = {
594 .owner = THIS_MODULE,
595 .name = "affs",
596 .mount = affs_mount,
597 .kill_sb = kill_block_super,
598 .fs_flags = FS_REQUIRES_DEV,
601 static int __init init_affs_fs(void)
603 int err = init_inodecache();
604 if (err)
605 goto out1;
606 err = register_filesystem(&affs_fs_type);
607 if (err)
608 goto out;
609 return 0;
610 out:
611 destroy_inodecache();
612 out1:
613 return err;
616 static void __exit exit_affs_fs(void)
618 unregister_filesystem(&affs_fs_type);
619 destroy_inodecache();
622 MODULE_DESCRIPTION("Amiga filesystem support for Linux");
623 MODULE_LICENSE("GPL");
625 module_init(init_affs_fs)
626 module_exit(exit_affs_fs)