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
9 * init_hfs_fs() and exit_hfs_fs(). The remaining super_ops are in
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
15 #include <linux/module.h>
16 #include <linux/blkdev.h>
17 #include <linux/backing-dev.h>
18 #include <linux/mount.h>
19 #include <linux/init.h>
20 #include <linux/nls.h>
21 #include <linux/parser.h>
22 #include <linux/seq_file.h>
23 #include <linux/slab.h>
24 #include <linux/vfs.h>
25
26 #include "hfs_fs.h"
27 #include "btree.h"
28
29 static struct kmem_cache *hfs_inode_cachep;
30
31 MODULE_DESCRIPTION("Apple Macintosh file system support");
32 MODULE_LICENSE("GPL");
33
34 static int hfs_sync_fs(struct super_block *sb, int wait)
35 {
36 hfs_mdb_commit(sb);
37 return 0;
38 }
39
40 /*
41 * hfs_put_super()
42 *
43 * This is the put_super() entry in the super_operations structure for
44 * HFS filesystems. The purpose is to release the resources
45 * associated with the superblock sb.
46 */
47 static void hfs_put_super(struct super_block *sb)
48 {
49 cancel_delayed_work_sync(&HFS_SB(sb)->mdb_work);
50 hfs_mdb_close(sb);
51 /* release the MDB's resources */
52 hfs_mdb_put(sb);
53 }
54
55 static void flush_mdb(struct work_struct *work)
56 {
57 struct hfs_sb_info *sbi;
58 struct super_block *sb;
59
60 sbi = container_of(work, struct hfs_sb_info, mdb_work.work);
61 sb = sbi->sb;
62
63 spin_lock(&sbi->work_lock);
64 sbi->work_queued = 0;
65 spin_unlock(&sbi->work_lock);
66
67 hfs_mdb_commit(sb);
68 }
69
70 void hfs_mark_mdb_dirty(struct super_block *sb)
71 {
72 struct hfs_sb_info *sbi = HFS_SB(sb);
73 unsigned long delay;
74
75 if (sb_rdonly(sb))
76 return;
77
78 spin_lock(&sbi->work_lock);
79 if (!sbi->work_queued) {
80 delay = msecs_to_jiffies(dirty_writeback_interval * 10);
81 queue_delayed_work(system_long_wq, &sbi->mdb_work, delay);
82 sbi->work_queued = 1;
83 }
84 spin_unlock(&sbi->work_lock);
85 }
86
87 /*
88 * hfs_statfs()
89 *
90 * This is the statfs() entry in the super_operations structure for
91 * HFS filesystems. The purpose is to return various data about the
92 * filesystem.
93 *
94 * changed f_files/f_ffree to reflect the fs_ablock/free_ablocks.
95 */
96 static int hfs_statfs(struct dentry *dentry, struct kstatfs *buf)
97 {
98 struct super_block *sb = dentry->d_sb;
99 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
100
101 buf->f_type = HFS_SUPER_MAGIC;
102 buf->f_bsize = sb->s_blocksize;
103 buf->f_blocks = (u32)HFS_SB(sb)->fs_ablocks * HFS_SB(sb)->fs_div;
104 buf->f_bfree = (u32)HFS_SB(sb)->free_ablocks * HFS_SB(sb)->fs_div;
105 buf->f_bavail = buf->f_bfree;
106 buf->f_files = HFS_SB(sb)->fs_ablocks;
107 buf->f_ffree = HFS_SB(sb)->free_ablocks;
108 buf->f_fsid = u64_to_fsid(id);
109 buf->f_namelen = HFS_NAMELEN;
110
111 return 0;
112 }
113
114 static int hfs_remount(struct super_block *sb, int *flags, char *data)
115 {
116 sync_filesystem(sb);
117 *flags |= SB_NODIRATIME;
118 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
119 return 0;
120 if (!(*flags & SB_RDONLY)) {
121 if (!(HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) {
122 pr_warn("filesystem was not cleanly unmounted, running fsck.hfs is recommended. leaving read-only.\n");
123 sb->s_flags |= SB_RDONLY;
124 *flags |= SB_RDONLY;
125 } else if (HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_SLOCK)) {
126 pr_warn("filesystem is marked locked, leaving read-only.\n");
127 sb->s_flags |= SB_RDONLY;
128 *flags |= SB_RDONLY;
129 }
130 }
131 return 0;
132 }
133
134 static int hfs_show_options(struct seq_file *seq, struct dentry *root)
135 {
136 struct hfs_sb_info *sbi = HFS_SB(root->d_sb);
137
138 if (sbi->s_creator != cpu_to_be32(0x3f3f3f3f))
139 seq_show_option_n(seq, "creator", (char *)&sbi->s_creator, 4);
140 if (sbi->s_type != cpu_to_be32(0x3f3f3f3f))
141 seq_show_option_n(seq, "type", (char *)&sbi->s_type, 4);
142 seq_printf(seq, ",uid=%u,gid=%u",
143 from_kuid_munged(&init_user_ns, sbi->s_uid),
144 from_kgid_munged(&init_user_ns, sbi->s_gid));
145 if (sbi->s_file_umask != 0133)
146 seq_printf(seq, ",file_umask=%o", sbi->s_file_umask);
147 if (sbi->s_dir_umask != 0022)
148 seq_printf(seq, ",dir_umask=%o", sbi->s_dir_umask);
149 if (sbi->part >= 0)
150 seq_printf(seq, ",part=%u", sbi->part);
151 if (sbi->session >= 0)
152 seq_printf(seq, ",session=%u", sbi->session);
153 if (sbi->nls_disk)
154 seq_printf(seq, ",codepage=%s", sbi->nls_disk->charset);
155 if (sbi->nls_io)
156 seq_printf(seq, ",iocharset=%s", sbi->nls_io->charset);
157 if (sbi->s_quiet)
158 seq_printf(seq, ",quiet");
159 return 0;
160 }
161
162 static struct inode *hfs_alloc_inode(struct super_block *sb)
163 {
164 struct hfs_inode_info *i;
165
166 i = alloc_inode_sb(sb, hfs_inode_cachep, GFP_KERNEL);
167 return i ? &i->vfs_inode : NULL;
168 }
169
170 static void hfs_free_inode(struct inode *inode)
171 {
172 kmem_cache_free(hfs_inode_cachep, HFS_I(inode));
173 }
174
175 static const struct super_operations hfs_super_operations = {
176 .alloc_inode = hfs_alloc_inode,
177 .free_inode = hfs_free_inode,
178 .write_inode = hfs_write_inode,
179 .evict_inode = hfs_evict_inode,
180 .put_super = hfs_put_super,
181 .sync_fs = hfs_sync_fs,
182 .statfs = hfs_statfs,
183 .remount_fs = hfs_remount,
184 .show_options = hfs_show_options,
185 };
186
187 enum {
188 opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask,
189 opt_part, opt_session, opt_type, opt_creator, opt_quiet,
190 opt_codepage, opt_iocharset,
191 opt_err
192 };
193
194 static const match_table_t tokens = {
195 { opt_uid, "uid=%u" },
196 { opt_gid, "gid=%u" },
197 { opt_umask, "umask=%o" },
198 { opt_file_umask, "file_umask=%o" },
199 { opt_dir_umask, "dir_umask=%o" },
200 { opt_part, "part=%u" },
201 { opt_session, "session=%u" },
202 { opt_type, "type=%s" },
203 { opt_creator, "creator=%s" },
204 { opt_quiet, "quiet" },
205 { opt_codepage, "codepage=%s" },
206 { opt_iocharset, "iocharset=%s" },
207 { opt_err, NULL }
208 };
209
210 static inline int match_fourchar(substring_t *arg, u32 *result)
211 {
212 if (arg->to - arg->from != 4)
213 return -EINVAL;
214 memcpy(result, arg->from, 4);
215 return 0;
216 }
217
218 /*
219 * parse_options()
220 *
221 * adapted from linux/fs/msdos/inode.c written 1992,93 by Werner Almesberger
222 * This function is called by hfs_read_super() to parse the mount options.
223 */
224 static int parse_options(char *options, struct hfs_sb_info *hsb)
225 {
226 char *p;
227 substring_t args[MAX_OPT_ARGS];
228 int tmp, token;
229
230 /* initialize the sb with defaults */
231 hsb->s_uid = current_uid();
232 hsb->s_gid = current_gid();
233 hsb->s_file_umask = 0133;
234 hsb->s_dir_umask = 0022;
235 hsb->s_type = hsb->s_creator = cpu_to_be32(0x3f3f3f3f); /* == '????' */
236 hsb->s_quiet = 0;
237 hsb->part = -1;
238 hsb->session = -1;
239
240 if (!options)
241 return 1;
242
243 while ((p = strsep(&options, ",")) != NULL) {
244 if (!*p)
245 continue;
246
247 token = match_token(p, tokens, args);
248 switch (token) {
249 case opt_uid:
250 if (match_int(&args[0], &tmp)) {
251 pr_err("uid requires an argument\n");
252 return 0;
253 }
254 hsb->s_uid = make_kuid(current_user_ns(), (uid_t)tmp);
255 if (!uid_valid(hsb->s_uid)) {
256 pr_err("invalid uid %d\n", tmp);
257 return 0;
258 }
259 break;
260 case opt_gid:
261 if (match_int(&args[0], &tmp)) {
262 pr_err("gid requires an argument\n");
263 return 0;
264 }
265 hsb->s_gid = make_kgid(current_user_ns(), (gid_t)tmp);
266 if (!gid_valid(hsb->s_gid)) {
267 pr_err("invalid gid %d\n", tmp);
268 return 0;
269 }
270 break;
271 case opt_umask:
272 if (match_octal(&args[0], &tmp)) {
273 pr_err("umask requires a value\n");
274 return 0;
275 }
276 hsb->s_file_umask = (umode_t)tmp;
277 hsb->s_dir_umask = (umode_t)tmp;
278 break;
279 case opt_file_umask:
280 if (match_octal(&args[0], &tmp)) {
281 pr_err("file_umask requires a value\n");
282 return 0;
283 }
284 hsb->s_file_umask = (umode_t)tmp;
285 break;
286 case opt_dir_umask:
287 if (match_octal(&args[0], &tmp)) {
288 pr_err("dir_umask requires a value\n");
289 return 0;
290 }
291 hsb->s_dir_umask = (umode_t)tmp;
292 break;
293 case opt_part:
294 if (match_int(&args[0], &hsb->part)) {
295 pr_err("part requires an argument\n");
296 return 0;
297 }
298 break;
299 case opt_session:
300 if (match_int(&args[0], &hsb->session)) {
301 pr_err("session requires an argument\n");
302 return 0;
303 }
304 break;
305 case opt_type:
306 if (match_fourchar(&args[0], &hsb->s_type)) {
307 pr_err("type requires a 4 character value\n");
308 return 0;
309 }
310 break;
311 case opt_creator:
312 if (match_fourchar(&args[0], &hsb->s_creator)) {
313 pr_err("creator requires a 4 character value\n");
314 return 0;
315 }
316 break;
317 case opt_quiet:
318 hsb->s_quiet = 1;
319 break;
320 case opt_codepage:
321 if (hsb->nls_disk) {
322 pr_err("unable to change codepage\n");
323 return 0;
324 }
325 p = match_strdup(&args[0]);
326 if (p)
327 hsb->nls_disk = load_nls(p);
328 if (!hsb->nls_disk) {
329 pr_err("unable to load codepage \"%s\"\n", p);
330 kfree(p);
331 return 0;
332 }
333 kfree(p);
334 break;
335 case opt_iocharset:
336 if (hsb->nls_io) {
337 pr_err("unable to change iocharset\n");
338 return 0;
339 }
340 p = match_strdup(&args[0]);
341 if (p)
342 hsb->nls_io = load_nls(p);
343 if (!hsb->nls_io) {
344 pr_err("unable to load iocharset \"%s\"\n", p);
345 kfree(p);
346 return 0;
347 }
348 kfree(p);
349 break;
350 default:
351 return 0;
352 }
353 }
354
355 if (hsb->nls_disk && !hsb->nls_io) {
356 hsb->nls_io = load_nls_default();
357 if (!hsb->nls_io) {
358 pr_err("unable to load default iocharset\n");
359 return 0;
360 }
361 }
362 hsb->s_dir_umask &= 0777;
363 hsb->s_file_umask &= 0577;
364
365 return 1;
366 }
367
368 /*
369 * hfs_read_super()
370 *
371 * This is the function that is responsible for mounting an HFS
372 * filesystem. It performs all the tasks necessary to get enough data
373 * from the disk to read the root inode. This includes parsing the
374 * mount options, dealing with Macintosh partitions, reading the
375 * superblock and the allocation bitmap blocks, calling
376 * hfs_btree_init() to get the necessary data about the extents and
377 * catalog B-trees and, finally, reading the root inode into memory.
378 */
379 static int hfs_fill_super(struct super_block *sb, void *data, int silent)
380 {
381 struct hfs_sb_info *sbi;
382 struct hfs_find_data fd;
383 hfs_cat_rec rec;
384 struct inode *root_inode;
385 int res;
386
387 sbi = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL);
388 if (!sbi)
389 return -ENOMEM;
390
391 sbi->sb = sb;
392 sb->s_fs_info = sbi;
393 spin_lock_init(&sbi->work_lock);
394 INIT_DELAYED_WORK(&sbi->mdb_work, flush_mdb);
395
396 res = -EINVAL;
397 if (!parse_options((char *)data, sbi)) {
398 pr_err("unable to parse mount options\n");
399 goto bail;
400 }
401
402 sb->s_op = &hfs_super_operations;
403 sb->s_xattr = hfs_xattr_handlers;
404 sb->s_flags |= SB_NODIRATIME;
405 mutex_init(&sbi->bitmap_lock);
406
407 res = hfs_mdb_get(sb);
408 if (res) {
409 if (!silent)
410 pr_warn("can't find a HFS filesystem on dev %s\n",
411 hfs_mdb_name(sb));
412 res = -EINVAL;
413 goto bail;
414 }
415
416 /* try to get the root inode */
417 res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
418 if (res)
419 goto bail_no_root;
420 res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd);
421 if (!res) {
422 if (fd.entrylength > sizeof(rec) || fd.entrylength < 0) {
423 res = -EIO;
424 goto bail_hfs_find;
425 }
426 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength);
427 }
428 if (res)
429 goto bail_hfs_find;
430 res = -EINVAL;
431 root_inode = hfs_iget(sb, &fd.search_key->cat, &rec);
432 hfs_find_exit(&fd);
433 if (!root_inode)
434 goto bail_no_root;
435
436 sb->s_d_op = &hfs_dentry_operations;
437 res = -ENOMEM;
438 sb->s_root = d_make_root(root_inode);
439 if (!sb->s_root)
440 goto bail_no_root;
441
442 /* everything's okay */
443 return 0;
444
445 bail_hfs_find:
446 hfs_find_exit(&fd);
447 bail_no_root:
448 pr_err("get root inode failed\n");
449 bail:
450 hfs_mdb_put(sb);
451 return res;
452 }
453
454 static struct dentry *hfs_mount(struct file_system_type *fs_type,
455 int flags, const char *dev_name, void *data)
456 {
457 return mount_bdev(fs_type, flags, dev_name, data, hfs_fill_super);
458 }
459
460 static struct file_system_type hfs_fs_type = {
461 .owner = THIS_MODULE,
462 .name = "hfs",
463 .mount = hfs_mount,
464 .kill_sb = kill_block_super,
465 .fs_flags = FS_REQUIRES_DEV,
466 };
467 MODULE_ALIAS_FS("hfs");
468
469 static void hfs_init_once(void *p)
470 {
471 struct hfs_inode_info *i = p;
472
473 inode_init_once(&i->vfs_inode);
474 }
475
476 static int __init init_hfs_fs(void)
477 {
478 int err;
479
480 hfs_inode_cachep = kmem_cache_create("hfs_inode_cache",
481 sizeof(struct hfs_inode_info), 0,
482 SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT, hfs_init_once);
483 if (!hfs_inode_cachep)
484 return -ENOMEM;
485 err = register_filesystem(&hfs_fs_type);
486 if (err)
487 kmem_cache_destroy(hfs_inode_cachep);
488 return err;
489 }
490
491 static void __exit exit_hfs_fs(void)
492 {
493 unregister_filesystem(&hfs_fs_type);
494
495 /*
496 * Make sure all delayed rcu free inodes are flushed before we
497 * destroy cache.
498 */
499 rcu_barrier();
500 kmem_cache_destroy(hfs_inode_cachep);
501 }
502
503 module_init(init_hfs_fs)
504 module_exit(exit_hfs_fs)
505
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