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 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength); 414 if (res) { 415 hfs_find_exit(&fd); 416 goto bail_no_root; 417 } 418 res = -EINVAL; 419 root_inode = hfs_iget(sb, &fd.search_key->cat, &rec); 420 hfs_find_exit(&fd); 421 if (!root_inode) 422 goto bail_no_root; 423 424 res = -ENOMEM; 425 sb->s_root = d_alloc_root(root_inode); 426 if (!sb->s_root) 427 goto bail_iput; 428 429 sb->s_root->d_op = &hfs_dentry_operations; 430 431 /* everything's okay */ 432 return 0; 433 434 bail_iput: 435 iput(root_inode); 436 bail_no_root: 437 printk(KERN_ERR "hfs: get root inode failed.\n"); 438 bail: 439 hfs_mdb_put(sb); 440 return res; 441 } 442 443 static int hfs_get_sb(struct file_system_type *fs_type, 444 int flags, const char *dev_name, void *data, 445 struct vfsmount *mnt) 446 { 447 return get_sb_bdev(fs_type, flags, dev_name, data, hfs_fill_super, mnt); 448 } 449 450 static struct file_system_type hfs_fs_type = { 451 .owner = THIS_MODULE, 452 .name = "hfs", 453 .get_sb = hfs_get_sb, 454 .kill_sb = kill_block_super, 455 .fs_flags = FS_REQUIRES_DEV, 456 }; 457 458 static void hfs_init_once(void *p) 459 { 460 struct hfs_inode_info *i = p; 461 462 inode_init_once(&i->vfs_inode); 463 } 464 465 static int __init init_hfs_fs(void) 466 { 467 int err; 468 469 hfs_inode_cachep = kmem_cache_create("hfs_inode_cache", 470 sizeof(struct hfs_inode_info), 0, SLAB_HWCACHE_ALIGN, 471 hfs_init_once); 472 if (!hfs_inode_cachep) 473 return -ENOMEM; 474 err = register_filesystem(&hfs_fs_type); 475 if (err) 476 kmem_cache_destroy(hfs_inode_cachep); 477 return err; 478 } 479 480 static void __exit exit_hfs_fs(void) 481 { 482 unregister_filesystem(&hfs_fs_type); 483 kmem_cache_destroy(hfs_inode_cachep); 484 } 485 486 module_init(init_hfs_fs) 487 module_exit(exit_hfs_fs) 488