Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6.git] / fs / hfs / super.c
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/mount.h>
18 #include <linux/init.h>
19 #include <linux/nls.h>
20 #include <linux/parser.h>
21 #include <linux/seq_file.h>
22 #include <linux/smp_lock.h>
23 #include <linux/vfs.h>
24
25 #include "hfs_fs.h"
26 #include "btree.h"
27
28 static struct kmem_cache *hfs_inode_cachep;
29
30 MODULE_LICENSE("GPL");
31
32 /*
33  * hfs_write_super()
34  *
35  * Description:
36  *   This function is called by the VFS only. When the filesystem
37  *   is mounted r/w it updates the MDB on disk.
38  * Input Variable(s):
39  *   struct super_block *sb: Pointer to the hfs superblock
40  * Output Variable(s):
41  *   NONE
42  * Returns:
43  *   void
44  * Preconditions:
45  *   'sb' points to a "valid" (struct super_block).
46  * Postconditions:
47  *   The MDB is marked 'unsuccessfully unmounted' by clearing bit 8 of drAtrb
48  *   (hfs_put_super() must set this flag!). Some MDB fields are updated
49  *   and the MDB buffer is written to disk by calling hfs_mdb_commit().
50  */
51 static void hfs_write_super(struct super_block *sb)
52 {
53         lock_super(sb);
54         sb->s_dirt = 0;
55
56         /* sync everything to the buffers */
57         if (!(sb->s_flags & MS_RDONLY))
58                 hfs_mdb_commit(sb);
59         unlock_super(sb);
60 }
61
62 static int hfs_sync_fs(struct super_block *sb, int wait)
63 {
64         lock_super(sb);
65         hfs_mdb_commit(sb);
66         sb->s_dirt = 0;
67         unlock_super(sb);
68
69         return 0;
70 }
71
72 /*
73  * hfs_put_super()
74  *
75  * This is the put_super() entry in the super_operations structure for
76  * HFS filesystems.  The purpose is to release the resources
77  * associated with the superblock sb.
78  */
79 static void hfs_put_super(struct super_block *sb)
80 {
81         lock_kernel();
82
83         if (sb->s_dirt)
84                 hfs_write_super(sb);
85         hfs_mdb_close(sb);
86         /* release the MDB's resources */
87         hfs_mdb_put(sb);
88
89         unlock_kernel();
90 }
91
92 /*
93  * hfs_statfs()
94  *
95  * This is the statfs() entry in the super_operations structure for
96  * HFS filesystems.  The purpose is to return various data about the
97  * filesystem.
98  *
99  * changed f_files/f_ffree to reflect the fs_ablock/free_ablocks.
100  */
101 static int hfs_statfs(struct dentry *dentry, struct kstatfs *buf)
102 {
103         struct super_block *sb = dentry->d_sb;
104         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
105
106         buf->f_type = HFS_SUPER_MAGIC;
107         buf->f_bsize = sb->s_blocksize;
108         buf->f_blocks = (u32)HFS_SB(sb)->fs_ablocks * HFS_SB(sb)->fs_div;
109         buf->f_bfree = (u32)HFS_SB(sb)->free_ablocks * HFS_SB(sb)->fs_div;
110         buf->f_bavail = buf->f_bfree;
111         buf->f_files = HFS_SB(sb)->fs_ablocks;
112         buf->f_ffree = HFS_SB(sb)->free_ablocks;
113         buf->f_fsid.val[0] = (u32)id;
114         buf->f_fsid.val[1] = (u32)(id >> 32);
115         buf->f_namelen = HFS_NAMELEN;
116
117         return 0;
118 }
119
120 static int hfs_remount(struct super_block *sb, int *flags, char *data)
121 {
122         *flags |= MS_NODIRATIME;
123         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
124                 return 0;
125         if (!(*flags & MS_RDONLY)) {
126                 if (!(HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) {
127                         printk(KERN_WARNING "hfs: filesystem was not cleanly unmounted, "
128                                "running fsck.hfs is recommended.  leaving read-only.\n");
129                         sb->s_flags |= MS_RDONLY;
130                         *flags |= MS_RDONLY;
131                 } else if (HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_SLOCK)) {
132                         printk(KERN_WARNING "hfs: filesystem is marked locked, leaving read-only.\n");
133                         sb->s_flags |= MS_RDONLY;
134                         *flags |= MS_RDONLY;
135                 }
136         }
137         return 0;
138 }
139
140 static int hfs_show_options(struct seq_file *seq, struct vfsmount *mnt)
141 {
142         struct hfs_sb_info *sbi = HFS_SB(mnt->mnt_sb);
143
144         if (sbi->s_creator != cpu_to_be32(0x3f3f3f3f))
145                 seq_printf(seq, ",creator=%.4s", (char *)&sbi->s_creator);
146         if (sbi->s_type != cpu_to_be32(0x3f3f3f3f))
147                 seq_printf(seq, ",type=%.4s", (char *)&sbi->s_type);
148         seq_printf(seq, ",uid=%u,gid=%u", sbi->s_uid, 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
166 static struct inode *hfs_alloc_inode(struct super_block *sb)
167 {
168         struct hfs_inode_info *i;
169
170         i = kmem_cache_alloc(hfs_inode_cachep, GFP_KERNEL);
171         return i ? &i->vfs_inode : NULL;
172 }
173
174 static void hfs_destroy_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         .destroy_inode  = hfs_destroy_inode,
182         .write_inode    = hfs_write_inode,
183         .clear_inode    = hfs_clear_inode,
184         .put_super      = hfs_put_super,
185         .write_super    = hfs_write_super,
186         .sync_fs        = hfs_sync_fs,
187         .statfs         = hfs_statfs,
188         .remount_fs     = hfs_remount,
189         .show_options   = hfs_show_options,
190 };
191
192 enum {
193         opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask,
194         opt_part, opt_session, opt_type, opt_creator, opt_quiet,
195         opt_codepage, opt_iocharset,
196         opt_err
197 };
198
199 static const match_table_t tokens = {
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" },
210         { opt_codepage, "codepage=%s" },
211         { opt_iocharset, "iocharset=%s" },
212         { opt_err, NULL }
213 };
214
215 static 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  */
229 static 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 */
236         hsb->s_uid = current_uid();
237         hsb->s_gid = current_gid();
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)) {
256                                 printk(KERN_ERR "hfs: uid requires an argument\n");
257                                 return 0;
258                         }
259                         hsb->s_uid = (uid_t)tmp;
260                         break;
261                 case opt_gid:
262                         if (match_int(&args[0], &tmp)) {
263                                 printk(KERN_ERR "hfs: gid requires an argument\n");
264                                 return 0;
265                         }
266                         hsb->s_gid = (gid_t)tmp;
267                         break;
268                 case opt_umask:
269                         if (match_octal(&args[0], &tmp)) {
270                                 printk(KERN_ERR "hfs: umask requires a value\n");
271                                 return 0;
272                         }
273                         hsb->s_file_umask = (umode_t)tmp;
274                         hsb->s_dir_umask = (umode_t)tmp;
275                         break;
276                 case opt_file_umask:
277                         if (match_octal(&args[0], &tmp)) {
278                                 printk(KERN_ERR "hfs: file_umask requires a value\n");
279                                 return 0;
280                         }
281                         hsb->s_file_umask = (umode_t)tmp;
282                         break;
283                 case opt_dir_umask:
284                         if (match_octal(&args[0], &tmp)) {
285                                 printk(KERN_ERR "hfs: dir_umask requires a value\n");
286                                 return 0;
287                         }
288                         hsb->s_dir_umask = (umode_t)tmp;
289                         break;
290                 case opt_part:
291                         if (match_int(&args[0], &hsb->part)) {
292                                 printk(KERN_ERR "hfs: part requires an argument\n");
293                                 return 0;
294                         }
295                         break;
296                 case opt_session:
297                         if (match_int(&args[0], &hsb->session)) {
298                                 printk(KERN_ERR "hfs: session requires an argument\n");
299                                 return 0;
300                         }
301                         break;
302                 case opt_type:
303                         if (match_fourchar(&args[0], &hsb->s_type)) {
304                                 printk(KERN_ERR "hfs: type requires a 4 character value\n");
305                                 return 0;
306                         }
307                         break;
308                 case opt_creator:
309                         if (match_fourchar(&args[0], &hsb->s_creator)) {
310                                 printk(KERN_ERR "hfs: creator requires a 4 character value\n");
311                                 return 0;
312                         }
313                         break;
314                 case opt_quiet:
315                         hsb->s_quiet = 1;
316                         break;
317                 case opt_codepage:
318                         if (hsb->nls_disk) {
319                                 printk(KERN_ERR "hfs: unable to change codepage\n");
320                                 return 0;
321                         }
322                         p = match_strdup(&args[0]);
323                         if (p)
324                                 hsb->nls_disk = load_nls(p);
325                         if (!hsb->nls_disk) {
326                                 printk(KERN_ERR "hfs: unable to load codepage \"%s\"\n", p);
327                                 kfree(p);
328                                 return 0;
329                         }
330                         kfree(p);
331                         break;
332                 case opt_iocharset:
333                         if (hsb->nls_io) {
334                                 printk(KERN_ERR "hfs: unable to change iocharset\n");
335                                 return 0;
336                         }
337                         p = match_strdup(&args[0]);
338                         if (p)
339                                 hsb->nls_io = load_nls(p);
340                         if (!hsb->nls_io) {
341                                 printk(KERN_ERR "hfs: unable to load iocharset \"%s\"\n", p);
342                                 kfree(p);
343                                 return 0;
344                         }
345                         kfree(p);
346                         break;
347                 default:
348                         return 0;
349                 }
350         }
351
352         if (hsb->nls_disk && !hsb->nls_io) {
353                 hsb->nls_io = load_nls_default();
354                 if (!hsb->nls_io) {
355                         printk(KERN_ERR "hfs: unable to load default iocharset\n");
356                         return 0;
357                 }
358         }
359         hsb->s_dir_umask &= 0777;
360         hsb->s_file_umask &= 0577;
361
362         return 1;
363 }
364
365 /*
366  * hfs_read_super()
367  *
368  * This is the function that is responsible for mounting an HFS
369  * filesystem.  It performs all the tasks necessary to get enough data
370  * from the disk to read the root inode.  This includes parsing the
371  * mount options, dealing with Macintosh partitions, reading the
372  * superblock and the allocation bitmap blocks, calling
373  * hfs_btree_init() to get the necessary data about the extents and
374  * catalog B-trees and, finally, reading the root inode into memory.
375  */
376 static int hfs_fill_super(struct super_block *sb, void *data, int silent)
377 {
378         struct hfs_sb_info *sbi;
379         struct hfs_find_data fd;
380         hfs_cat_rec rec;
381         struct inode *root_inode;
382         int res;
383
384         sbi = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL);
385         if (!sbi)
386                 return -ENOMEM;
387         sb->s_fs_info = sbi;
388         INIT_HLIST_HEAD(&sbi->rsrc_inodes);
389
390         res = -EINVAL;
391         if (!parse_options((char *)data, sbi)) {
392                 printk(KERN_ERR "hfs: unable to parse mount options.\n");
393                 goto bail;
394         }
395
396         sb->s_op = &hfs_super_operations;
397         sb->s_flags |= MS_NODIRATIME;
398         mutex_init(&sbi->bitmap_lock);
399
400         res = hfs_mdb_get(sb);
401         if (res) {
402                 if (!silent)
403                         printk(KERN_WARNING "hfs: can't find a HFS filesystem on dev %s.\n",
404                                 hfs_mdb_name(sb));
405                 res = -EINVAL;
406                 goto bail;
407         }
408
409         /* try to get the root inode */
410         hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
411         res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd);
412         if (!res) {
413                 if (fd.entrylength > sizeof(rec) || fd.entrylength < 0) {
414                         res =  -EIO;
415                         goto bail;
416                 }
417                 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength);
418         }
419         if (res) {
420                 hfs_find_exit(&fd);
421                 goto bail_no_root;
422         }
423         res = -EINVAL;
424         root_inode = hfs_iget(sb, &fd.search_key->cat, &rec);
425         hfs_find_exit(&fd);
426         if (!root_inode)
427                 goto bail_no_root;
428
429         res = -ENOMEM;
430         sb->s_root = d_alloc_root(root_inode);
431         if (!sb->s_root)
432                 goto bail_iput;
433
434         sb->s_root->d_op = &hfs_dentry_operations;
435
436         /* everything's okay */
437         return 0;
438
439 bail_iput:
440         iput(root_inode);
441 bail_no_root:
442         printk(KERN_ERR "hfs: get root inode failed.\n");
443 bail:
444         hfs_mdb_put(sb);
445         return res;
446 }
447
448 static int hfs_get_sb(struct file_system_type *fs_type,
449                       int flags, const char *dev_name, void *data,
450                       struct vfsmount *mnt)
451 {
452         return get_sb_bdev(fs_type, flags, dev_name, data, hfs_fill_super, mnt);
453 }
454
455 static struct file_system_type hfs_fs_type = {
456         .owner          = THIS_MODULE,
457         .name           = "hfs",
458         .get_sb         = hfs_get_sb,
459         .kill_sb        = kill_block_super,
460         .fs_flags       = FS_REQUIRES_DEV,
461 };
462
463 static void hfs_init_once(void *p)
464 {
465         struct hfs_inode_info *i = p;
466
467         inode_init_once(&i->vfs_inode);
468 }
469
470 static int __init init_hfs_fs(void)
471 {
472         int err;
473
474         hfs_inode_cachep = kmem_cache_create("hfs_inode_cache",
475                 sizeof(struct hfs_inode_info), 0, SLAB_HWCACHE_ALIGN,
476                 hfs_init_once);
477         if (!hfs_inode_cachep)
478                 return -ENOMEM;
479         err = register_filesystem(&hfs_fs_type);
480         if (err)
481                 kmem_cache_destroy(hfs_inode_cachep);
482         return err;
483 }
484
485 static void __exit exit_hfs_fs(void)
486 {
487         unregister_filesystem(&hfs_fs_type);
488         kmem_cache_destroy(hfs_inode_cachep);
489 }
490
491 module_init(init_hfs_fs)
492 module_exit(exit_hfs_fs)