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CommitLineData
1da177e4
LT
1/*
2 * linux/fs/hfs/super.c
3 *
4 * Copyright (C) 1995-1997 Paul H. Hargrove
5 * (C) 2003 Ardis Technologies <roman@ardistech.com>
6 * This file may be distributed under the terms of the GNU General Public License.
7 *
8 * This file contains hfs_read_super(), some of the super_ops and
14b30d62 9 * init_hfs_fs() and exit_hfs_fs(). The remaining super_ops are in
1da177e4
LT
10 * inode.c since they deal with inodes.
11 *
12 * Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds
13 */
14
1da177e4
LT
15#include <linux/module.h>
16#include <linux/blkdev.h>
717dd80e 17#include <linux/mount.h>
1da177e4 18#include <linux/init.h>
328b9227 19#include <linux/nls.h>
1da177e4 20#include <linux/parser.h>
717dd80e 21#include <linux/seq_file.h>
5a0e3ad6 22#include <linux/slab.h>
1da177e4
LT
23#include <linux/vfs.h>
24
25#include "hfs_fs.h"
26#include "btree.h"
27
e18b890b 28static struct kmem_cache *hfs_inode_cachep;
1da177e4
LT
29
30MODULE_LICENSE("GPL");
31
58bc5bbb
CH
32static int hfs_sync_fs(struct super_block *sb, int wait)
33{
58bc5bbb 34 hfs_mdb_commit(sb);
58bc5bbb
CH
35 return 0;
36}
37
1da177e4
LT
38/*
39 * hfs_put_super()
40 *
41 * This is the put_super() entry in the super_operations structure for
42 * HFS filesystems. The purpose is to release the resources
43 * associated with the superblock sb.
44 */
45static void hfs_put_super(struct super_block *sb)
46{
5687b578 47 cancel_delayed_work_sync(&HFS_SB(sb)->mdb_work);
1da177e4
LT
48 hfs_mdb_close(sb);
49 /* release the MDB's resources */
50 hfs_mdb_put(sb);
51}
52
5687b578
AB
53static void flush_mdb(struct work_struct *work)
54{
55 struct hfs_sb_info *sbi;
56 struct super_block *sb;
57
58 sbi = container_of(work, struct hfs_sb_info, mdb_work.work);
59 sb = sbi->sb;
60
61 spin_lock(&sbi->work_lock);
62 sbi->work_queued = 0;
63 spin_unlock(&sbi->work_lock);
64
65 hfs_mdb_commit(sb);
66}
67
68void hfs_mark_mdb_dirty(struct super_block *sb)
69{
70 struct hfs_sb_info *sbi = HFS_SB(sb);
71 unsigned long delay;
72
73 if (sb->s_flags & MS_RDONLY)
74 return;
75
76 spin_lock(&sbi->work_lock);
77 if (!sbi->work_queued) {
78 delay = msecs_to_jiffies(dirty_writeback_interval * 10);
79 queue_delayed_work(system_long_wq, &sbi->mdb_work, delay);
80 sbi->work_queued = 1;
81 }
82 spin_unlock(&sbi->work_lock);
83}
84
1da177e4
LT
85/*
86 * hfs_statfs()
87 *
88 * This is the statfs() entry in the super_operations structure for
89 * HFS filesystems. The purpose is to return various data about the
90 * filesystem.
91 *
92 * changed f_files/f_ffree to reflect the fs_ablock/free_ablocks.
93 */
726c3342 94static int hfs_statfs(struct dentry *dentry, struct kstatfs *buf)
1da177e4 95{
726c3342 96 struct super_block *sb = dentry->d_sb;
7dd2c000 97 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
726c3342 98
1da177e4
LT
99 buf->f_type = HFS_SUPER_MAGIC;
100 buf->f_bsize = sb->s_blocksize;
101 buf->f_blocks = (u32)HFS_SB(sb)->fs_ablocks * HFS_SB(sb)->fs_div;
102 buf->f_bfree = (u32)HFS_SB(sb)->free_ablocks * HFS_SB(sb)->fs_div;
103 buf->f_bavail = buf->f_bfree;
104 buf->f_files = HFS_SB(sb)->fs_ablocks;
105 buf->f_ffree = HFS_SB(sb)->free_ablocks;
7dd2c000
CL
106 buf->f_fsid.val[0] = (u32)id;
107 buf->f_fsid.val[1] = (u32)(id >> 32);
1da177e4
LT
108 buf->f_namelen = HFS_NAMELEN;
109
110 return 0;
111}
112
113static int hfs_remount(struct super_block *sb, int *flags, char *data)
114{
115 *flags |= MS_NODIRATIME;
116 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
117 return 0;
118 if (!(*flags & MS_RDONLY)) {
119 if (!(HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) {
7cf3cc30 120 printk(KERN_WARNING "hfs: filesystem was not cleanly unmounted, "
1da177e4
LT
121 "running fsck.hfs is recommended. leaving read-only.\n");
122 sb->s_flags |= MS_RDONLY;
123 *flags |= MS_RDONLY;
124 } else if (HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_SLOCK)) {
7cf3cc30 125 printk(KERN_WARNING "hfs: filesystem is marked locked, leaving read-only.\n");
1da177e4
LT
126 sb->s_flags |= MS_RDONLY;
127 *flags |= MS_RDONLY;
128 }
129 }
130 return 0;
131}
132
34c80b1d 133static int hfs_show_options(struct seq_file *seq, struct dentry *root)
717dd80e 134{
34c80b1d 135 struct hfs_sb_info *sbi = HFS_SB(root->d_sb);
717dd80e
RZ
136
137 if (sbi->s_creator != cpu_to_be32(0x3f3f3f3f))
138 seq_printf(seq, ",creator=%.4s", (char *)&sbi->s_creator);
139 if (sbi->s_type != cpu_to_be32(0x3f3f3f3f))
140 seq_printf(seq, ",type=%.4s", (char *)&sbi->s_type);
43b5e4cc
EB
141 seq_printf(seq, ",uid=%u,gid=%u",
142 from_kuid_munged(&init_user_ns, sbi->s_uid),
143 from_kgid_munged(&init_user_ns, sbi->s_gid));
717dd80e
RZ
144 if (sbi->s_file_umask != 0133)
145 seq_printf(seq, ",file_umask=%o", sbi->s_file_umask);
146 if (sbi->s_dir_umask != 0022)
147 seq_printf(seq, ",dir_umask=%o", sbi->s_dir_umask);
148 if (sbi->part >= 0)
149 seq_printf(seq, ",part=%u", sbi->part);
150 if (sbi->session >= 0)
151 seq_printf(seq, ",session=%u", sbi->session);
328b9227
RZ
152 if (sbi->nls_disk)
153 seq_printf(seq, ",codepage=%s", sbi->nls_disk->charset);
154 if (sbi->nls_io)
155 seq_printf(seq, ",iocharset=%s", sbi->nls_io->charset);
717dd80e
RZ
156 if (sbi->s_quiet)
157 seq_printf(seq, ",quiet");
158 return 0;
159}
160
1da177e4
LT
161static struct inode *hfs_alloc_inode(struct super_block *sb)
162{
163 struct hfs_inode_info *i;
164
e94b1766 165 i = kmem_cache_alloc(hfs_inode_cachep, GFP_KERNEL);
1da177e4
LT
166 return i ? &i->vfs_inode : NULL;
167}
168
fa0d7e3d 169static void hfs_i_callback(struct rcu_head *head)
1da177e4 170{
fa0d7e3d 171 struct inode *inode = container_of(head, struct inode, i_rcu);
1da177e4
LT
172 kmem_cache_free(hfs_inode_cachep, HFS_I(inode));
173}
174
fa0d7e3d
NP
175static void hfs_destroy_inode(struct inode *inode)
176{
177 call_rcu(&inode->i_rcu, hfs_i_callback);
178}
179
ee9b6d61 180static const struct super_operations hfs_super_operations = {
1da177e4
LT
181 .alloc_inode = hfs_alloc_inode,
182 .destroy_inode = hfs_destroy_inode,
183 .write_inode = hfs_write_inode,
b57922d9 184 .evict_inode = hfs_evict_inode,
1da177e4 185 .put_super = hfs_put_super,
58bc5bbb 186 .sync_fs = hfs_sync_fs,
1da177e4
LT
187 .statfs = hfs_statfs,
188 .remount_fs = hfs_remount,
717dd80e 189 .show_options = hfs_show_options,
1da177e4
LT
190};
191
192enum {
193 opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask,
194 opt_part, opt_session, opt_type, opt_creator, opt_quiet,
328b9227 195 opt_codepage, opt_iocharset,
1da177e4
LT
196 opt_err
197};
198
a447c093 199static const match_table_t tokens = {
1da177e4
LT
200 { opt_uid, "uid=%u" },
201 { opt_gid, "gid=%u" },
202 { opt_umask, "umask=%o" },
203 { opt_file_umask, "file_umask=%o" },
204 { opt_dir_umask, "dir_umask=%o" },
205 { opt_part, "part=%u" },
206 { opt_session, "session=%u" },
207 { opt_type, "type=%s" },
208 { opt_creator, "creator=%s" },
209 { opt_quiet, "quiet" },
328b9227
RZ
210 { opt_codepage, "codepage=%s" },
211 { opt_iocharset, "iocharset=%s" },
1da177e4
LT
212 { opt_err, NULL }
213};
214
215static inline int match_fourchar(substring_t *arg, u32 *result)
216{
217 if (arg->to - arg->from != 4)
218 return -EINVAL;
219 memcpy(result, arg->from, 4);
220 return 0;
221}
222
223/*
224 * parse_options()
225 *
226 * adapted from linux/fs/msdos/inode.c written 1992,93 by Werner Almesberger
227 * This function is called by hfs_read_super() to parse the mount options.
228 */
229static int parse_options(char *options, struct hfs_sb_info *hsb)
230{
231 char *p;
232 substring_t args[MAX_OPT_ARGS];
233 int tmp, token;
234
235 /* initialize the sb with defaults */
94c9a5ee
DH
236 hsb->s_uid = current_uid();
237 hsb->s_gid = current_gid();
1da177e4
LT
238 hsb->s_file_umask = 0133;
239 hsb->s_dir_umask = 0022;
240 hsb->s_type = hsb->s_creator = cpu_to_be32(0x3f3f3f3f); /* == '????' */
241 hsb->s_quiet = 0;
242 hsb->part = -1;
243 hsb->session = -1;
244
245 if (!options)
246 return 1;
247
248 while ((p = strsep(&options, ",")) != NULL) {
249 if (!*p)
250 continue;
251
252 token = match_token(p, tokens, args);
253 switch (token) {
254 case opt_uid:
255 if (match_int(&args[0], &tmp)) {
7cf3cc30 256 printk(KERN_ERR "hfs: uid requires an argument\n");
1da177e4
LT
257 return 0;
258 }
43b5e4cc
EB
259 hsb->s_uid = make_kuid(current_user_ns(), (uid_t)tmp);
260 if (!uid_valid(hsb->s_uid)) {
261 printk(KERN_ERR "hfs: invalid uid %d\n", tmp);
262 return 0;
263 }
1da177e4
LT
264 break;
265 case opt_gid:
266 if (match_int(&args[0], &tmp)) {
7cf3cc30 267 printk(KERN_ERR "hfs: gid requires an argument\n");
1da177e4
LT
268 return 0;
269 }
43b5e4cc
EB
270 hsb->s_gid = make_kgid(current_user_ns(), (gid_t)tmp);
271 if (!gid_valid(hsb->s_gid)) {
272 printk(KERN_ERR "hfs: invalid gid %d\n", tmp);
273 return 0;
274 }
1da177e4
LT
275 break;
276 case opt_umask:
277 if (match_octal(&args[0], &tmp)) {
7cf3cc30 278 printk(KERN_ERR "hfs: umask requires a value\n");
1da177e4
LT
279 return 0;
280 }
281 hsb->s_file_umask = (umode_t)tmp;
282 hsb->s_dir_umask = (umode_t)tmp;
283 break;
284 case opt_file_umask:
285 if (match_octal(&args[0], &tmp)) {
7cf3cc30 286 printk(KERN_ERR "hfs: file_umask requires a value\n");
1da177e4
LT
287 return 0;
288 }
289 hsb->s_file_umask = (umode_t)tmp;
290 break;
291 case opt_dir_umask:
292 if (match_octal(&args[0], &tmp)) {
7cf3cc30 293 printk(KERN_ERR "hfs: dir_umask requires a value\n");
1da177e4
LT
294 return 0;
295 }
296 hsb->s_dir_umask = (umode_t)tmp;
297 break;
298 case opt_part:
299 if (match_int(&args[0], &hsb->part)) {
7cf3cc30 300 printk(KERN_ERR "hfs: part requires an argument\n");
1da177e4
LT
301 return 0;
302 }
303 break;
304 case opt_session:
305 if (match_int(&args[0], &hsb->session)) {
7cf3cc30 306 printk(KERN_ERR "hfs: session requires an argument\n");
1da177e4
LT
307 return 0;
308 }
309 break;
310 case opt_type:
311 if (match_fourchar(&args[0], &hsb->s_type)) {
7cf3cc30 312 printk(KERN_ERR "hfs: type requires a 4 character value\n");
1da177e4
LT
313 return 0;
314 }
315 break;
316 case opt_creator:
317 if (match_fourchar(&args[0], &hsb->s_creator)) {
7cf3cc30 318 printk(KERN_ERR "hfs: creator requires a 4 character value\n");
1da177e4
LT
319 return 0;
320 }
321 break;
322 case opt_quiet:
323 hsb->s_quiet = 1;
324 break;
328b9227
RZ
325 case opt_codepage:
326 if (hsb->nls_disk) {
7cf3cc30 327 printk(KERN_ERR "hfs: unable to change codepage\n");
328b9227
RZ
328 return 0;
329 }
330 p = match_strdup(&args[0]);
3fbe5c31
JM
331 if (p)
332 hsb->nls_disk = load_nls(p);
328b9227 333 if (!hsb->nls_disk) {
7cf3cc30 334 printk(KERN_ERR "hfs: unable to load codepage \"%s\"\n", p);
328b9227
RZ
335 kfree(p);
336 return 0;
337 }
338 kfree(p);
339 break;
340 case opt_iocharset:
341 if (hsb->nls_io) {
7cf3cc30 342 printk(KERN_ERR "hfs: unable to change iocharset\n");
328b9227
RZ
343 return 0;
344 }
345 p = match_strdup(&args[0]);
3fbe5c31
JM
346 if (p)
347 hsb->nls_io = load_nls(p);
328b9227 348 if (!hsb->nls_io) {
7cf3cc30 349 printk(KERN_ERR "hfs: unable to load iocharset \"%s\"\n", p);
328b9227
RZ
350 kfree(p);
351 return 0;
352 }
353 kfree(p);
354 break;
1da177e4
LT
355 default:
356 return 0;
357 }
358 }
359
328b9227
RZ
360 if (hsb->nls_disk && !hsb->nls_io) {
361 hsb->nls_io = load_nls_default();
362 if (!hsb->nls_io) {
7cf3cc30 363 printk(KERN_ERR "hfs: unable to load default iocharset\n");
328b9227
RZ
364 return 0;
365 }
366 }
1da177e4
LT
367 hsb->s_dir_umask &= 0777;
368 hsb->s_file_umask &= 0577;
369
370 return 1;
371}
372
373/*
374 * hfs_read_super()
375 *
376 * This is the function that is responsible for mounting an HFS
377 * filesystem. It performs all the tasks necessary to get enough data
378 * from the disk to read the root inode. This includes parsing the
379 * mount options, dealing with Macintosh partitions, reading the
380 * superblock and the allocation bitmap blocks, calling
381 * hfs_btree_init() to get the necessary data about the extents and
382 * catalog B-trees and, finally, reading the root inode into memory.
383 */
384static int hfs_fill_super(struct super_block *sb, void *data, int silent)
385{
386 struct hfs_sb_info *sbi;
387 struct hfs_find_data fd;
388 hfs_cat_rec rec;
389 struct inode *root_inode;
390 int res;
391
f8314dc6 392 sbi = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL);
8526fb37 393 if (!sbi)
1da177e4 394 return -ENOMEM;
8526fb37 395
b16ca626 396 sbi->sb = sb;
1da177e4 397 sb->s_fs_info = sbi;
5687b578
AB
398 spin_lock_init(&sbi->work_lock);
399 INIT_DELAYED_WORK(&sbi->mdb_work, flush_mdb);
1da177e4
LT
400
401 res = -EINVAL;
402 if (!parse_options((char *)data, sbi)) {
7cf3cc30 403 printk(KERN_ERR "hfs: unable to parse mount options.\n");
945b0920 404 goto bail;
1da177e4
LT
405 }
406
407 sb->s_op = &hfs_super_operations;
408 sb->s_flags |= MS_NODIRATIME;
3084b72d 409 mutex_init(&sbi->bitmap_lock);
1da177e4
LT
410
411 res = hfs_mdb_get(sb);
412 if (res) {
413 if (!silent)
7cf3cc30 414 printk(KERN_WARNING "hfs: can't find a HFS filesystem on dev %s.\n",
1da177e4
LT
415 hfs_mdb_name(sb));
416 res = -EINVAL;
945b0920 417 goto bail;
1da177e4
LT
418 }
419
420 /* try to get the root inode */
421 hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
422 res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd);
ec81aecb
AW
423 if (!res) {
424 if (fd.entrylength > sizeof(rec) || fd.entrylength < 0) {
425 res = -EIO;
426 goto bail;
427 }
1da177e4 428 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength);
ec81aecb 429 }
1da177e4
LT
430 if (res) {
431 hfs_find_exit(&fd);
432 goto bail_no_root;
433 }
d6ddf554 434 res = -EINVAL;
1da177e4
LT
435 root_inode = hfs_iget(sb, &fd.search_key->cat, &rec);
436 hfs_find_exit(&fd);
437 if (!root_inode)
438 goto bail_no_root;
439
518c79d2 440 sb->s_d_op = &hfs_dentry_operations;
d6ddf554 441 res = -ENOMEM;
48fde701 442 sb->s_root = d_make_root(root_inode);
1da177e4 443 if (!sb->s_root)
48fde701 444 goto bail_no_root;
1da177e4 445
1da177e4
LT
446 /* everything's okay */
447 return 0;
448
1da177e4 449bail_no_root:
7cf3cc30 450 printk(KERN_ERR "hfs: get root inode failed.\n");
945b0920 451bail:
1da177e4 452 hfs_mdb_put(sb);
1da177e4
LT
453 return res;
454}
455
152a0836
AV
456static struct dentry *hfs_mount(struct file_system_type *fs_type,
457 int flags, const char *dev_name, void *data)
1da177e4 458{
152a0836 459 return mount_bdev(fs_type, flags, dev_name, data, hfs_fill_super);
1da177e4
LT
460}
461
462static struct file_system_type hfs_fs_type = {
463 .owner = THIS_MODULE,
464 .name = "hfs",
152a0836 465 .mount = hfs_mount,
1da177e4
LT
466 .kill_sb = kill_block_super,
467 .fs_flags = FS_REQUIRES_DEV,
468};
7f78e035 469MODULE_ALIAS_FS("hfs");
1da177e4 470
51cc5068 471static void hfs_init_once(void *p)
1da177e4
LT
472{
473 struct hfs_inode_info *i = p;
474
a35afb83 475 inode_init_once(&i->vfs_inode);
1da177e4
LT
476}
477
478static int __init init_hfs_fs(void)
479{
480 int err;
481
482 hfs_inode_cachep = kmem_cache_create("hfs_inode_cache",
483 sizeof(struct hfs_inode_info), 0, SLAB_HWCACHE_ALIGN,
20c2df83 484 hfs_init_once);
1da177e4
LT
485 if (!hfs_inode_cachep)
486 return -ENOMEM;
487 err = register_filesystem(&hfs_fs_type);
488 if (err)
489 kmem_cache_destroy(hfs_inode_cachep);
490 return err;
491}
492
493static void __exit exit_hfs_fs(void)
494{
495 unregister_filesystem(&hfs_fs_type);
8c0a8537
KS
496
497 /*
498 * Make sure all delayed rcu free inodes are flushed before we
499 * destroy cache.
500 */
501 rcu_barrier();
1a1d92c1 502 kmem_cache_destroy(hfs_inode_cachep);
1da177e4
LT
503}
504
505module_init(init_hfs_fs)
506module_exit(exit_hfs_fs)