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/fs_context.h>
19 #include <linux/fs_parser.h>
20 #include <linux/mount.h>
21 #include <linux/init.h>
22 #include <linux/nls.h>
23 #include <linux/seq_file.h>
24 #include <linux/slab.h>
25 #include <linux/vfs.h>
26
27 #include "hfs_fs.h"
28 #include "btree.h"
29
30 static struct kmem_cache *hfs_inode_cachep;
31
32 MODULE_DESCRIPTION("Apple Macintosh file system support");
33 MODULE_LICENSE("GPL");
34
hfs_sync_fs(struct super_block * sb,int wait)35 static int hfs_sync_fs(struct super_block *sb, int wait)
36 {
37 hfs_mdb_commit(sb);
38 return 0;
39 }
40
41 /*
42 * hfs_put_super()
43 *
44 * This is the put_super() entry in the super_operations structure for
45 * HFS filesystems. The purpose is to release the resources
46 * associated with the superblock sb.
47 */
hfs_put_super(struct super_block * sb)48 static void hfs_put_super(struct super_block *sb)
49 {
50 cancel_delayed_work_sync(&HFS_SB(sb)->mdb_work);
51 hfs_mdb_close(sb);
52 /* release the MDB's resources */
53 hfs_mdb_put(sb);
54 }
55
flush_mdb(struct work_struct * work)56 static void flush_mdb(struct work_struct *work)
57 {
58 struct hfs_sb_info *sbi;
59 struct super_block *sb;
60
61 sbi = container_of(work, struct hfs_sb_info, mdb_work.work);
62 sb = sbi->sb;
63
64 spin_lock(&sbi->work_lock);
65 sbi->work_queued = 0;
66 spin_unlock(&sbi->work_lock);
67
68 hfs_mdb_commit(sb);
69 }
70
hfs_mark_mdb_dirty(struct super_block * sb)71 void hfs_mark_mdb_dirty(struct super_block *sb)
72 {
73 struct hfs_sb_info *sbi = HFS_SB(sb);
74 unsigned long delay;
75
76 if (sb_rdonly(sb))
77 return;
78
79 spin_lock(&sbi->work_lock);
80 if (!sbi->work_queued) {
81 delay = msecs_to_jiffies(dirty_writeback_interval * 10);
82 queue_delayed_work(system_long_wq, &sbi->mdb_work, delay);
83 sbi->work_queued = 1;
84 }
85 spin_unlock(&sbi->work_lock);
86 }
87
88 /*
89 * hfs_statfs()
90 *
91 * This is the statfs() entry in the super_operations structure for
92 * HFS filesystems. The purpose is to return various data about the
93 * filesystem.
94 *
95 * changed f_files/f_ffree to reflect the fs_ablock/free_ablocks.
96 */
hfs_statfs(struct dentry * dentry,struct kstatfs * buf)97 static int hfs_statfs(struct dentry *dentry, struct kstatfs *buf)
98 {
99 struct super_block *sb = dentry->d_sb;
100 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
101
102 buf->f_type = HFS_SUPER_MAGIC;
103 buf->f_bsize = sb->s_blocksize;
104 buf->f_blocks = (u32)HFS_SB(sb)->fs_ablocks * HFS_SB(sb)->fs_div;
105 buf->f_bfree = (u32)HFS_SB(sb)->free_ablocks * HFS_SB(sb)->fs_div;
106 buf->f_bavail = buf->f_bfree;
107 buf->f_files = HFS_SB(sb)->fs_ablocks;
108 buf->f_ffree = HFS_SB(sb)->free_ablocks;
109 buf->f_fsid = u64_to_fsid(id);
110 buf->f_namelen = HFS_NAMELEN;
111
112 return 0;
113 }
114
hfs_reconfigure(struct fs_context * fc)115 static int hfs_reconfigure(struct fs_context *fc)
116 {
117 struct super_block *sb = fc->root->d_sb;
118
119 sync_filesystem(sb);
120 fc->sb_flags |= SB_NODIRATIME;
121 if ((bool)(fc->sb_flags & SB_RDONLY) == sb_rdonly(sb))
122 return 0;
123
124 if (!(fc->sb_flags & SB_RDONLY)) {
125 if (!(HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) {
126 pr_warn("filesystem was not cleanly unmounted, running fsck.hfs is recommended. leaving read-only.\n");
127 sb->s_flags |= SB_RDONLY;
128 fc->sb_flags |= SB_RDONLY;
129 } else if (HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_SLOCK)) {
130 pr_warn("filesystem is marked locked, leaving read-only.\n");
131 sb->s_flags |= SB_RDONLY;
132 fc->sb_flags |= SB_RDONLY;
133 }
134 }
135 return 0;
136 }
137
hfs_show_options(struct seq_file * seq,struct dentry * root)138 static int hfs_show_options(struct seq_file *seq, struct dentry *root)
139 {
140 struct hfs_sb_info *sbi = HFS_SB(root->d_sb);
141
142 if (sbi->s_creator != cpu_to_be32(0x3f3f3f3f))
143 seq_show_option_n(seq, "creator", (char *)&sbi->s_creator, 4);
144 if (sbi->s_type != cpu_to_be32(0x3f3f3f3f))
145 seq_show_option_n(seq, "type", (char *)&sbi->s_type, 4);
146 seq_printf(seq, ",uid=%u,gid=%u",
147 from_kuid_munged(&init_user_ns, sbi->s_uid),
148 from_kgid_munged(&init_user_ns, sbi->s_gid));
149 if (sbi->s_file_umask != 0133)
150 seq_printf(seq, ",file_umask=%o", sbi->s_file_umask);
151 if (sbi->s_dir_umask != 0022)
152 seq_printf(seq, ",dir_umask=%o", sbi->s_dir_umask);
153 if (sbi->part >= 0)
154 seq_printf(seq, ",part=%u", sbi->part);
155 if (sbi->session >= 0)
156 seq_printf(seq, ",session=%u", sbi->session);
157 if (sbi->nls_disk)
158 seq_printf(seq, ",codepage=%s", sbi->nls_disk->charset);
159 if (sbi->nls_io)
160 seq_printf(seq, ",iocharset=%s", sbi->nls_io->charset);
161 if (sbi->s_quiet)
162 seq_printf(seq, ",quiet");
163 return 0;
164 }
165
hfs_alloc_inode(struct super_block * sb)166 static struct inode *hfs_alloc_inode(struct super_block *sb)
167 {
168 struct hfs_inode_info *i;
169
170 i = alloc_inode_sb(sb, hfs_inode_cachep, GFP_KERNEL);
171 return i ? &i->vfs_inode : NULL;
172 }
173
hfs_free_inode(struct inode * inode)174 static void hfs_free_inode(struct inode *inode)
175 {
176 kmem_cache_free(hfs_inode_cachep, HFS_I(inode));
177 }
178
179 static const struct super_operations hfs_super_operations = {
180 .alloc_inode = hfs_alloc_inode,
181 .free_inode = hfs_free_inode,
182 .write_inode = hfs_write_inode,
183 .evict_inode = hfs_evict_inode,
184 .put_super = hfs_put_super,
185 .sync_fs = hfs_sync_fs,
186 .statfs = hfs_statfs,
187 .show_options = hfs_show_options,
188 };
189
190 enum {
191 opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask,
192 opt_part, opt_session, opt_type, opt_creator, opt_quiet,
193 opt_codepage, opt_iocharset,
194 };
195
196 static const struct fs_parameter_spec hfs_param_spec[] = {
197 fsparam_u32 ("uid", opt_uid),
198 fsparam_u32 ("gid", opt_gid),
199 fsparam_u32oct ("umask", opt_umask),
200 fsparam_u32oct ("file_umask", opt_file_umask),
201 fsparam_u32oct ("dir_umask", opt_dir_umask),
202 fsparam_u32 ("part", opt_part),
203 fsparam_u32 ("session", opt_session),
204 fsparam_string ("type", opt_type),
205 fsparam_string ("creator", opt_creator),
206 fsparam_flag ("quiet", opt_quiet),
207 fsparam_string ("codepage", opt_codepage),
208 fsparam_string ("iocharset", opt_iocharset),
209 {}
210 };
211
212 /*
213 * hfs_parse_param()
214 *
215 * This function is called by the vfs to parse the mount options.
216 */
hfs_parse_param(struct fs_context * fc,struct fs_parameter * param)217 static int hfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
218 {
219 struct hfs_sb_info *hsb = fc->s_fs_info;
220 struct fs_parse_result result;
221 int opt;
222
223 /* hfs does not honor any fs-specific options on remount */
224 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE)
225 return 0;
226
227 opt = fs_parse(fc, hfs_param_spec, param, &result);
228 if (opt < 0)
229 return opt;
230
231 switch (opt) {
232 case opt_uid:
233 hsb->s_uid = result.uid;
234 break;
235 case opt_gid:
236 hsb->s_gid = result.gid;
237 break;
238 case opt_umask:
239 hsb->s_file_umask = (umode_t)result.uint_32;
240 hsb->s_dir_umask = (umode_t)result.uint_32;
241 break;
242 case opt_file_umask:
243 hsb->s_file_umask = (umode_t)result.uint_32;
244 break;
245 case opt_dir_umask:
246 hsb->s_dir_umask = (umode_t)result.uint_32;
247 break;
248 case opt_part:
249 hsb->part = result.uint_32;
250 break;
251 case opt_session:
252 hsb->session = result.uint_32;
253 break;
254 case opt_type:
255 if (strlen(param->string) != 4) {
256 pr_err("type requires a 4 character value\n");
257 return -EINVAL;
258 }
259 memcpy(&hsb->s_type, param->string, 4);
260 break;
261 case opt_creator:
262 if (strlen(param->string) != 4) {
263 pr_err("creator requires a 4 character value\n");
264 return -EINVAL;
265 }
266 memcpy(&hsb->s_creator, param->string, 4);
267 break;
268 case opt_quiet:
269 hsb->s_quiet = 1;
270 break;
271 case opt_codepage:
272 if (hsb->nls_disk) {
273 pr_err("unable to change codepage\n");
274 return -EINVAL;
275 }
276 hsb->nls_disk = load_nls(param->string);
277 if (!hsb->nls_disk) {
278 pr_err("unable to load codepage \"%s\"\n",
279 param->string);
280 return -EINVAL;
281 }
282 break;
283 case opt_iocharset:
284 if (hsb->nls_io) {
285 pr_err("unable to change iocharset\n");
286 return -EINVAL;
287 }
288 hsb->nls_io = load_nls(param->string);
289 if (!hsb->nls_io) {
290 pr_err("unable to load iocharset \"%s\"\n",
291 param->string);
292 return -EINVAL;
293 }
294 break;
295 default:
296 return -EINVAL;
297 }
298
299 return 0;
300 }
301
302 /*
303 * hfs_read_super()
304 *
305 * This is the function that is responsible for mounting an HFS
306 * filesystem. It performs all the tasks necessary to get enough data
307 * from the disk to read the root inode. This includes parsing the
308 * mount options, dealing with Macintosh partitions, reading the
309 * superblock and the allocation bitmap blocks, calling
310 * hfs_btree_init() to get the necessary data about the extents and
311 * catalog B-trees and, finally, reading the root inode into memory.
312 */
hfs_fill_super(struct super_block * sb,struct fs_context * fc)313 static int hfs_fill_super(struct super_block *sb, struct fs_context *fc)
314 {
315 struct hfs_sb_info *sbi = HFS_SB(sb);
316 struct hfs_find_data fd;
317 hfs_cat_rec rec;
318 struct inode *root_inode;
319 int silent = fc->sb_flags & SB_SILENT;
320 int res;
321
322 atomic64_set(&sbi->file_count, 0);
323 atomic64_set(&sbi->folder_count, 0);
324 atomic64_set(&sbi->next_id, 0);
325
326 /* load_nls_default does not fail */
327 if (sbi->nls_disk && !sbi->nls_io)
328 sbi->nls_io = load_nls_default();
329 sbi->s_dir_umask &= 0777;
330 sbi->s_file_umask &= 0577;
331
332 spin_lock_init(&sbi->work_lock);
333 INIT_DELAYED_WORK(&sbi->mdb_work, flush_mdb);
334
335 sbi->sb = sb;
336 sb->s_op = &hfs_super_operations;
337 sb->s_xattr = hfs_xattr_handlers;
338 sb->s_flags |= SB_NODIRATIME;
339 mutex_init(&sbi->bitmap_lock);
340
341 res = hfs_mdb_get(sb);
342 if (res) {
343 if (!silent)
344 pr_warn("can't find a HFS filesystem on dev %s\n",
345 hfs_mdb_name(sb));
346 res = -EINVAL;
347 goto bail;
348 }
349
350 /* try to get the root inode */
351 res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
352 if (res)
353 goto bail_no_root;
354 res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd);
355 if (!res) {
356 if (fd.entrylength != sizeof(rec.dir)) {
357 res = -EIO;
358 goto bail_hfs_find;
359 }
360 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength);
361 if (rec.type != HFS_CDR_DIR)
362 res = -EIO;
363 }
364 if (res)
365 goto bail_hfs_find;
366 res = -EINVAL;
367 root_inode = hfs_iget(sb, &fd.search_key->cat, &rec);
368 hfs_find_exit(&fd);
369 if (!root_inode)
370 goto bail_no_root;
371
372 set_default_d_op(sb, &hfs_dentry_operations);
373 res = -ENOMEM;
374 sb->s_root = d_make_root(root_inode);
375 if (!sb->s_root)
376 goto bail_no_root;
377
378 /* everything's okay */
379 return 0;
380
381 bail_hfs_find:
382 hfs_find_exit(&fd);
383 bail_no_root:
384 pr_err("get root inode failed\n");
385 bail:
386 hfs_mdb_put(sb);
387 return res;
388 }
389
hfs_get_tree(struct fs_context * fc)390 static int hfs_get_tree(struct fs_context *fc)
391 {
392 return get_tree_bdev(fc, hfs_fill_super);
393 }
394
hfs_free_fc(struct fs_context * fc)395 static void hfs_free_fc(struct fs_context *fc)
396 {
397 kfree(fc->s_fs_info);
398 }
399
400 static const struct fs_context_operations hfs_context_ops = {
401 .parse_param = hfs_parse_param,
402 .get_tree = hfs_get_tree,
403 .reconfigure = hfs_reconfigure,
404 .free = hfs_free_fc,
405 };
406
hfs_init_fs_context(struct fs_context * fc)407 static int hfs_init_fs_context(struct fs_context *fc)
408 {
409 struct hfs_sb_info *hsb;
410
411 hsb = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL);
412 if (!hsb)
413 return -ENOMEM;
414
415 fc->s_fs_info = hsb;
416 fc->ops = &hfs_context_ops;
417
418 if (fc->purpose != FS_CONTEXT_FOR_RECONFIGURE) {
419 /* initialize options with defaults */
420 hsb->s_uid = current_uid();
421 hsb->s_gid = current_gid();
422 hsb->s_file_umask = 0133;
423 hsb->s_dir_umask = 0022;
424 hsb->s_type = cpu_to_be32(0x3f3f3f3f); /* == '????' */
425 hsb->s_creator = cpu_to_be32(0x3f3f3f3f); /* == '????' */
426 hsb->s_quiet = 0;
427 hsb->part = -1;
428 hsb->session = -1;
429 }
430
431 return 0;
432 }
433
434 static struct file_system_type hfs_fs_type = {
435 .owner = THIS_MODULE,
436 .name = "hfs",
437 .kill_sb = kill_block_super,
438 .fs_flags = FS_REQUIRES_DEV,
439 .init_fs_context = hfs_init_fs_context,
440 };
441 MODULE_ALIAS_FS("hfs");
442
hfs_init_once(void * p)443 static void hfs_init_once(void *p)
444 {
445 struct hfs_inode_info *i = p;
446
447 inode_init_once(&i->vfs_inode);
448 }
449
init_hfs_fs(void)450 static int __init init_hfs_fs(void)
451 {
452 int err;
453
454 hfs_inode_cachep = kmem_cache_create("hfs_inode_cache",
455 sizeof(struct hfs_inode_info), 0,
456 SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT, hfs_init_once);
457 if (!hfs_inode_cachep)
458 return -ENOMEM;
459 err = register_filesystem(&hfs_fs_type);
460 if (err)
461 kmem_cache_destroy(hfs_inode_cachep);
462 return err;
463 }
464
exit_hfs_fs(void)465 static void __exit exit_hfs_fs(void)
466 {
467 unregister_filesystem(&hfs_fs_type);
468
469 /*
470 * Make sure all delayed rcu free inodes are flushed before we
471 * destroy cache.
472 */
473 rcu_barrier();
474 kmem_cache_destroy(hfs_inode_cachep);
475 }
476
477 module_init(init_hfs_fs)
478 module_exit(exit_hfs_fs)
479