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