MNT_UNBINDABLE fix
[linux-2.6] / fs / hfsplus / super.c
1 /*
2  *  linux/fs/hfsplus/super.c
3  *
4  * Copyright (C) 2001
5  * Brad Boyer (flar@allandria.com)
6  * (C) 2003 Ardis Technologies <roman@ardistech.com>
7  *
8  */
9
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/pagemap.h>
13 #include <linux/fs.h>
14 #include <linux/slab.h>
15 #include <linux/vfs.h>
16 #include <linux/nls.h>
17
18 static struct inode *hfsplus_alloc_inode(struct super_block *sb);
19 static void hfsplus_destroy_inode(struct inode *inode);
20
21 #include "hfsplus_fs.h"
22
23 static void hfsplus_read_inode(struct inode *inode)
24 {
25         struct hfs_find_data fd;
26         struct hfsplus_vh *vhdr;
27         int err;
28
29         INIT_LIST_HEAD(&HFSPLUS_I(inode).open_dir_list);
30         init_MUTEX(&HFSPLUS_I(inode).extents_lock);
31         HFSPLUS_I(inode).flags = 0;
32         HFSPLUS_I(inode).rsrc_inode = NULL;
33         atomic_set(&HFSPLUS_I(inode).opencnt, 0);
34
35         if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID) {
36         read_inode:
37                 hfs_find_init(HFSPLUS_SB(inode->i_sb).cat_tree, &fd);
38                 err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
39                 if (!err)
40                         err = hfsplus_cat_read_inode(inode, &fd);
41                 hfs_find_exit(&fd);
42                 if (err)
43                         goto bad_inode;
44                 return;
45         }
46         vhdr = HFSPLUS_SB(inode->i_sb).s_vhdr;
47         switch(inode->i_ino) {
48         case HFSPLUS_ROOT_CNID:
49                 goto read_inode;
50         case HFSPLUS_EXT_CNID:
51                 hfsplus_inode_read_fork(inode, &vhdr->ext_file);
52                 inode->i_mapping->a_ops = &hfsplus_btree_aops;
53                 break;
54         case HFSPLUS_CAT_CNID:
55                 hfsplus_inode_read_fork(inode, &vhdr->cat_file);
56                 inode->i_mapping->a_ops = &hfsplus_btree_aops;
57                 break;
58         case HFSPLUS_ALLOC_CNID:
59                 hfsplus_inode_read_fork(inode, &vhdr->alloc_file);
60                 inode->i_mapping->a_ops = &hfsplus_aops;
61                 break;
62         case HFSPLUS_START_CNID:
63                 hfsplus_inode_read_fork(inode, &vhdr->start_file);
64                 break;
65         case HFSPLUS_ATTR_CNID:
66                 hfsplus_inode_read_fork(inode, &vhdr->attr_file);
67                 inode->i_mapping->a_ops = &hfsplus_btree_aops;
68                 break;
69         default:
70                 goto bad_inode;
71         }
72
73         return;
74
75  bad_inode:
76         make_bad_inode(inode);
77 }
78
79 static int hfsplus_write_inode(struct inode *inode, int unused)
80 {
81         struct hfsplus_vh *vhdr;
82         int ret = 0;
83
84         dprint(DBG_INODE, "hfsplus_write_inode: %lu\n", inode->i_ino);
85         hfsplus_ext_write_extent(inode);
86         if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID) {
87                 return hfsplus_cat_write_inode(inode);
88         }
89         vhdr = HFSPLUS_SB(inode->i_sb).s_vhdr;
90         switch (inode->i_ino) {
91         case HFSPLUS_ROOT_CNID:
92                 ret = hfsplus_cat_write_inode(inode);
93                 break;
94         case HFSPLUS_EXT_CNID:
95                 if (vhdr->ext_file.total_size != cpu_to_be64(inode->i_size)) {
96                         HFSPLUS_SB(inode->i_sb).flags |= HFSPLUS_SB_WRITEBACKUP;
97                         inode->i_sb->s_dirt = 1;
98                 }
99                 hfsplus_inode_write_fork(inode, &vhdr->ext_file);
100                 hfs_btree_write(HFSPLUS_SB(inode->i_sb).ext_tree);
101                 break;
102         case HFSPLUS_CAT_CNID:
103                 if (vhdr->cat_file.total_size != cpu_to_be64(inode->i_size)) {
104                         HFSPLUS_SB(inode->i_sb).flags |= HFSPLUS_SB_WRITEBACKUP;
105                         inode->i_sb->s_dirt = 1;
106                 }
107                 hfsplus_inode_write_fork(inode, &vhdr->cat_file);
108                 hfs_btree_write(HFSPLUS_SB(inode->i_sb).cat_tree);
109                 break;
110         case HFSPLUS_ALLOC_CNID:
111                 if (vhdr->alloc_file.total_size != cpu_to_be64(inode->i_size)) {
112                         HFSPLUS_SB(inode->i_sb).flags |= HFSPLUS_SB_WRITEBACKUP;
113                         inode->i_sb->s_dirt = 1;
114                 }
115                 hfsplus_inode_write_fork(inode, &vhdr->alloc_file);
116                 break;
117         case HFSPLUS_START_CNID:
118                 if (vhdr->start_file.total_size != cpu_to_be64(inode->i_size)) {
119                         HFSPLUS_SB(inode->i_sb).flags |= HFSPLUS_SB_WRITEBACKUP;
120                         inode->i_sb->s_dirt = 1;
121                 }
122                 hfsplus_inode_write_fork(inode, &vhdr->start_file);
123                 break;
124         case HFSPLUS_ATTR_CNID:
125                 if (vhdr->attr_file.total_size != cpu_to_be64(inode->i_size)) {
126                         HFSPLUS_SB(inode->i_sb).flags |= HFSPLUS_SB_WRITEBACKUP;
127                         inode->i_sb->s_dirt = 1;
128                 }
129                 hfsplus_inode_write_fork(inode, &vhdr->attr_file);
130                 hfs_btree_write(HFSPLUS_SB(inode->i_sb).attr_tree);
131                 break;
132         }
133         return ret;
134 }
135
136 static void hfsplus_clear_inode(struct inode *inode)
137 {
138         dprint(DBG_INODE, "hfsplus_clear_inode: %lu\n", inode->i_ino);
139         if (HFSPLUS_IS_RSRC(inode)) {
140                 HFSPLUS_I(HFSPLUS_I(inode).rsrc_inode).rsrc_inode = NULL;
141                 iput(HFSPLUS_I(inode).rsrc_inode);
142         }
143 }
144
145 static void hfsplus_write_super(struct super_block *sb)
146 {
147         struct hfsplus_vh *vhdr = HFSPLUS_SB(sb).s_vhdr;
148
149         dprint(DBG_SUPER, "hfsplus_write_super\n");
150         sb->s_dirt = 0;
151         if (sb->s_flags & MS_RDONLY)
152                 /* warn? */
153                 return;
154
155         vhdr->free_blocks = cpu_to_be32(HFSPLUS_SB(sb).free_blocks);
156         vhdr->next_alloc = cpu_to_be32(HFSPLUS_SB(sb).next_alloc);
157         vhdr->next_cnid = cpu_to_be32(HFSPLUS_SB(sb).next_cnid);
158         vhdr->folder_count = cpu_to_be32(HFSPLUS_SB(sb).folder_count);
159         vhdr->file_count = cpu_to_be32(HFSPLUS_SB(sb).file_count);
160
161         mark_buffer_dirty(HFSPLUS_SB(sb).s_vhbh);
162         if (HFSPLUS_SB(sb).flags & HFSPLUS_SB_WRITEBACKUP) {
163                 if (HFSPLUS_SB(sb).sect_count) {
164                         struct buffer_head *bh;
165                         u32 block, offset;
166
167                         block = HFSPLUS_SB(sb).blockoffset;
168                         block += (HFSPLUS_SB(sb).sect_count - 2) >> (sb->s_blocksize_bits - 9);
169                         offset = ((HFSPLUS_SB(sb).sect_count - 2) << 9) & (sb->s_blocksize - 1);
170                         printk(KERN_DEBUG "hfs: backup: %u,%u,%u,%u\n", HFSPLUS_SB(sb).blockoffset,
171                                 HFSPLUS_SB(sb).sect_count, block, offset);
172                         bh = sb_bread(sb, block);
173                         if (bh) {
174                                 vhdr = (struct hfsplus_vh *)(bh->b_data + offset);
175                                 if (be16_to_cpu(vhdr->signature) == HFSPLUS_VOLHEAD_SIG) {
176                                         memcpy(vhdr, HFSPLUS_SB(sb).s_vhdr, sizeof(*vhdr));
177                                         mark_buffer_dirty(bh);
178                                         brelse(bh);
179                                 } else
180                                         printk(KERN_WARNING "hfs: backup not found!\n");
181                         }
182                 }
183                 HFSPLUS_SB(sb).flags &= ~HFSPLUS_SB_WRITEBACKUP;
184         }
185 }
186
187 static void hfsplus_put_super(struct super_block *sb)
188 {
189         dprint(DBG_SUPER, "hfsplus_put_super\n");
190         if (!sb->s_fs_info)
191                 return;
192         if (!(sb->s_flags & MS_RDONLY) && HFSPLUS_SB(sb).s_vhdr) {
193                 struct hfsplus_vh *vhdr = HFSPLUS_SB(sb).s_vhdr;
194
195                 vhdr->modify_date = hfsp_now2mt();
196                 vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_UNMNT);
197                 vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_INCNSTNT);
198                 mark_buffer_dirty(HFSPLUS_SB(sb).s_vhbh);
199                 sync_dirty_buffer(HFSPLUS_SB(sb).s_vhbh);
200         }
201
202         hfs_btree_close(HFSPLUS_SB(sb).cat_tree);
203         hfs_btree_close(HFSPLUS_SB(sb).ext_tree);
204         iput(HFSPLUS_SB(sb).alloc_file);
205         iput(HFSPLUS_SB(sb).hidden_dir);
206         brelse(HFSPLUS_SB(sb).s_vhbh);
207         if (HFSPLUS_SB(sb).nls)
208                 unload_nls(HFSPLUS_SB(sb).nls);
209         kfree(sb->s_fs_info);
210         sb->s_fs_info = NULL;
211 }
212
213 static int hfsplus_statfs(struct dentry *dentry, struct kstatfs *buf)
214 {
215         struct super_block *sb = dentry->d_sb;
216
217         buf->f_type = HFSPLUS_SUPER_MAGIC;
218         buf->f_bsize = sb->s_blocksize;
219         buf->f_blocks = HFSPLUS_SB(sb).total_blocks << HFSPLUS_SB(sb).fs_shift;
220         buf->f_bfree = HFSPLUS_SB(sb).free_blocks << HFSPLUS_SB(sb).fs_shift;
221         buf->f_bavail = buf->f_bfree;
222         buf->f_files = 0xFFFFFFFF;
223         buf->f_ffree = 0xFFFFFFFF - HFSPLUS_SB(sb).next_cnid;
224         buf->f_namelen = HFSPLUS_MAX_STRLEN;
225
226         return 0;
227 }
228
229 static int hfsplus_remount(struct super_block *sb, int *flags, char *data)
230 {
231         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
232                 return 0;
233         if (!(*flags & MS_RDONLY)) {
234                 struct hfsplus_vh *vhdr = HFSPLUS_SB(sb).s_vhdr;
235                 struct hfsplus_sb_info sbi;
236
237                 memset(&sbi, 0, sizeof(struct hfsplus_sb_info));
238                 sbi.nls = HFSPLUS_SB(sb).nls;
239                 if (!hfsplus_parse_options(data, &sbi))
240                         return -EINVAL;
241
242                 if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
243                         printk(KERN_WARNING "hfs: filesystem was not cleanly unmounted, "
244                                "running fsck.hfsplus is recommended.  leaving read-only.\n");
245                         sb->s_flags |= MS_RDONLY;
246                         *flags |= MS_RDONLY;
247                 } else if (sbi.flags & HFSPLUS_SB_FORCE) {
248                         /* nothing */
249                 } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
250                         printk(KERN_WARNING "hfs: filesystem is marked locked, leaving read-only.\n");
251                         sb->s_flags |= MS_RDONLY;
252                         *flags |= MS_RDONLY;
253                 } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) {
254                         printk(KERN_WARNING "hfs: filesystem is marked journaled, leaving read-only.\n");
255                         sb->s_flags |= MS_RDONLY;
256                         *flags |= MS_RDONLY;
257                 }
258         }
259         return 0;
260 }
261
262 static const struct super_operations hfsplus_sops = {
263         .alloc_inode    = hfsplus_alloc_inode,
264         .destroy_inode  = hfsplus_destroy_inode,
265         .read_inode     = hfsplus_read_inode,
266         .write_inode    = hfsplus_write_inode,
267         .clear_inode    = hfsplus_clear_inode,
268         .put_super      = hfsplus_put_super,
269         .write_super    = hfsplus_write_super,
270         .statfs         = hfsplus_statfs,
271         .remount_fs     = hfsplus_remount,
272         .show_options   = hfsplus_show_options,
273 };
274
275 static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
276 {
277         struct hfsplus_vh *vhdr;
278         struct hfsplus_sb_info *sbi;
279         hfsplus_cat_entry entry;
280         struct hfs_find_data fd;
281         struct inode *root;
282         struct qstr str;
283         struct nls_table *nls = NULL;
284         int err = -EINVAL;
285
286         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
287         if (!sbi)
288                 return -ENOMEM;
289
290         sb->s_fs_info = sbi;
291         INIT_HLIST_HEAD(&sbi->rsrc_inodes);
292         hfsplus_fill_defaults(sbi);
293         if (!hfsplus_parse_options(data, sbi)) {
294                 printk(KERN_ERR "hfs: unable to parse mount options\n");
295                 err = -EINVAL;
296                 goto cleanup;
297         }
298
299         /* temporarily use utf8 to correctly find the hidden dir below */
300         nls = sbi->nls;
301         sbi->nls = load_nls("utf8");
302         if (!sbi->nls) {
303                 printk(KERN_ERR "hfs: unable to load nls for utf8\n");
304                 err = -EINVAL;
305                 goto cleanup;
306         }
307
308         /* Grab the volume header */
309         if (hfsplus_read_wrapper(sb)) {
310                 if (!silent)
311                         printk(KERN_WARNING "hfs: unable to find HFS+ superblock\n");
312                 err = -EINVAL;
313                 goto cleanup;
314         }
315         vhdr = HFSPLUS_SB(sb).s_vhdr;
316
317         /* Copy parts of the volume header into the superblock */
318         sb->s_magic = HFSPLUS_VOLHEAD_SIG;
319         if (be16_to_cpu(vhdr->version) < HFSPLUS_MIN_VERSION ||
320             be16_to_cpu(vhdr->version) > HFSPLUS_CURRENT_VERSION) {
321                 printk(KERN_ERR "hfs: wrong filesystem version\n");
322                 goto cleanup;
323         }
324         HFSPLUS_SB(sb).total_blocks = be32_to_cpu(vhdr->total_blocks);
325         HFSPLUS_SB(sb).free_blocks = be32_to_cpu(vhdr->free_blocks);
326         HFSPLUS_SB(sb).next_alloc = be32_to_cpu(vhdr->next_alloc);
327         HFSPLUS_SB(sb).next_cnid = be32_to_cpu(vhdr->next_cnid);
328         HFSPLUS_SB(sb).file_count = be32_to_cpu(vhdr->file_count);
329         HFSPLUS_SB(sb).folder_count = be32_to_cpu(vhdr->folder_count);
330         HFSPLUS_SB(sb).data_clump_blocks = be32_to_cpu(vhdr->data_clump_sz) >> HFSPLUS_SB(sb).alloc_blksz_shift;
331         if (!HFSPLUS_SB(sb).data_clump_blocks)
332                 HFSPLUS_SB(sb).data_clump_blocks = 1;
333         HFSPLUS_SB(sb).rsrc_clump_blocks = be32_to_cpu(vhdr->rsrc_clump_sz) >> HFSPLUS_SB(sb).alloc_blksz_shift;
334         if (!HFSPLUS_SB(sb).rsrc_clump_blocks)
335                 HFSPLUS_SB(sb).rsrc_clump_blocks = 1;
336
337         /* Set up operations so we can load metadata */
338         sb->s_op = &hfsplus_sops;
339         sb->s_maxbytes = MAX_LFS_FILESIZE;
340
341         if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
342                 printk(KERN_WARNING "hfs: Filesystem was not cleanly unmounted, "
343                        "running fsck.hfsplus is recommended.  mounting read-only.\n");
344                 sb->s_flags |= MS_RDONLY;
345         } else if (sbi->flags & HFSPLUS_SB_FORCE) {
346                 /* nothing */
347         } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
348                 printk(KERN_WARNING "hfs: Filesystem is marked locked, mounting read-only.\n");
349                 sb->s_flags |= MS_RDONLY;
350         } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) {
351                 printk(KERN_WARNING "hfs: write access to a jounaled filesystem is not supported, "
352                        "use the force option at your own risk, mounting read-only.\n");
353                 sb->s_flags |= MS_RDONLY;
354         }
355         sbi->flags &= ~HFSPLUS_SB_FORCE;
356
357         /* Load metadata objects (B*Trees) */
358         HFSPLUS_SB(sb).ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);
359         if (!HFSPLUS_SB(sb).ext_tree) {
360                 printk(KERN_ERR "hfs: failed to load extents file\n");
361                 goto cleanup;
362         }
363         HFSPLUS_SB(sb).cat_tree = hfs_btree_open(sb, HFSPLUS_CAT_CNID);
364         if (!HFSPLUS_SB(sb).cat_tree) {
365                 printk(KERN_ERR "hfs: failed to load catalog file\n");
366                 goto cleanup;
367         }
368
369         HFSPLUS_SB(sb).alloc_file = iget(sb, HFSPLUS_ALLOC_CNID);
370         if (!HFSPLUS_SB(sb).alloc_file) {
371                 printk(KERN_ERR "hfs: failed to load allocation file\n");
372                 goto cleanup;
373         }
374
375         /* Load the root directory */
376         root = iget(sb, HFSPLUS_ROOT_CNID);
377         sb->s_root = d_alloc_root(root);
378         if (!sb->s_root) {
379                 printk(KERN_ERR "hfs: failed to load root directory\n");
380                 iput(root);
381                 goto cleanup;
382         }
383         sb->s_root->d_op = &hfsplus_dentry_operations;
384
385         str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
386         str.name = HFSP_HIDDENDIR_NAME;
387         hfs_find_init(HFSPLUS_SB(sb).cat_tree, &fd);
388         hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, &str);
389         if (!hfs_brec_read(&fd, &entry, sizeof(entry))) {
390                 hfs_find_exit(&fd);
391                 if (entry.type != cpu_to_be16(HFSPLUS_FOLDER))
392                         goto cleanup;
393                 HFSPLUS_SB(sb).hidden_dir = iget(sb, be32_to_cpu(entry.folder.id));
394                 if (!HFSPLUS_SB(sb).hidden_dir)
395                         goto cleanup;
396         } else
397                 hfs_find_exit(&fd);
398
399         if (sb->s_flags & MS_RDONLY)
400                 goto out;
401
402         /* H+LX == hfsplusutils, H+Lx == this driver, H+lx is unused
403          * all three are registered with Apple for our use
404          */
405         vhdr->last_mount_vers = cpu_to_be32(HFSP_MOUNT_VERSION);
406         vhdr->modify_date = hfsp_now2mt();
407         vhdr->write_count = cpu_to_be32(be32_to_cpu(vhdr->write_count) + 1);
408         vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_UNMNT);
409         vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_INCNSTNT);
410         mark_buffer_dirty(HFSPLUS_SB(sb).s_vhbh);
411         sync_dirty_buffer(HFSPLUS_SB(sb).s_vhbh);
412
413         if (!HFSPLUS_SB(sb).hidden_dir) {
414                 printk(KERN_DEBUG "hfs: create hidden dir...\n");
415                 HFSPLUS_SB(sb).hidden_dir = hfsplus_new_inode(sb, S_IFDIR);
416                 hfsplus_create_cat(HFSPLUS_SB(sb).hidden_dir->i_ino, sb->s_root->d_inode,
417                                    &str, HFSPLUS_SB(sb).hidden_dir);
418                 mark_inode_dirty(HFSPLUS_SB(sb).hidden_dir);
419         }
420 out:
421         unload_nls(sbi->nls);
422         sbi->nls = nls;
423         return 0;
424
425 cleanup:
426         hfsplus_put_super(sb);
427         if (nls)
428                 unload_nls(nls);
429         return err;
430 }
431
432 MODULE_AUTHOR("Brad Boyer");
433 MODULE_DESCRIPTION("Extended Macintosh Filesystem");
434 MODULE_LICENSE("GPL");
435
436 static struct kmem_cache *hfsplus_inode_cachep;
437
438 static struct inode *hfsplus_alloc_inode(struct super_block *sb)
439 {
440         struct hfsplus_inode_info *i;
441
442         i = kmem_cache_alloc(hfsplus_inode_cachep, GFP_KERNEL);
443         return i ? &i->vfs_inode : NULL;
444 }
445
446 static void hfsplus_destroy_inode(struct inode *inode)
447 {
448         kmem_cache_free(hfsplus_inode_cachep, &HFSPLUS_I(inode));
449 }
450
451 #define HFSPLUS_INODE_SIZE      sizeof(struct hfsplus_inode_info)
452
453 static int hfsplus_get_sb(struct file_system_type *fs_type,
454                           int flags, const char *dev_name, void *data,
455                           struct vfsmount *mnt)
456 {
457         return get_sb_bdev(fs_type, flags, dev_name, data, hfsplus_fill_super,
458                            mnt);
459 }
460
461 static struct file_system_type hfsplus_fs_type = {
462         .owner          = THIS_MODULE,
463         .name           = "hfsplus",
464         .get_sb         = hfsplus_get_sb,
465         .kill_sb        = kill_block_super,
466         .fs_flags       = FS_REQUIRES_DEV,
467 };
468
469 static void hfsplus_init_once(struct kmem_cache *cachep, void *p)
470 {
471         struct hfsplus_inode_info *i = p;
472
473         inode_init_once(&i->vfs_inode);
474 }
475
476 static int __init init_hfsplus_fs(void)
477 {
478         int err;
479
480         hfsplus_inode_cachep = kmem_cache_create("hfsplus_icache",
481                 HFSPLUS_INODE_SIZE, 0, SLAB_HWCACHE_ALIGN,
482                 hfsplus_init_once);
483         if (!hfsplus_inode_cachep)
484                 return -ENOMEM;
485         err = register_filesystem(&hfsplus_fs_type);
486         if (err)
487                 kmem_cache_destroy(hfsplus_inode_cachep);
488         return err;
489 }
490
491 static void __exit exit_hfsplus_fs(void)
492 {
493         unregister_filesystem(&hfsplus_fs_type);
494         kmem_cache_destroy(hfsplus_inode_cachep);
495 }
496
497 module_init(init_hfsplus_fs)
498 module_exit(exit_hfsplus_fs)