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 sync_filesystem(sb); 116 *flags |= MS_NODIRATIME; 117 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 118 return 0; 119 if (!(*flags & MS_RDONLY)) { 120 if (!(HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) { 121 pr_warn("filesystem was not cleanly unmounted, 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 pr_warn("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", 142 from_kuid_munged(&init_user_ns, sbi->s_uid), 143 from_kgid_munged(&init_user_ns, sbi->s_gid)); 144 if (sbi->s_file_umask != 0133) 145 seq_printf(seq, ",file_umask=%o", sbi->s_file_umask); 146 if (sbi->s_dir_umask != 0022) 147 seq_printf(seq, ",dir_umask=%o", sbi->s_dir_umask); 148 if (sbi->part >= 0) 149 seq_printf(seq, ",part=%u", sbi->part); 150 if (sbi->session >= 0) 151 seq_printf(seq, ",session=%u", sbi->session); 152 if (sbi->nls_disk) 153 seq_printf(seq, ",codepage=%s", sbi->nls_disk->charset); 154 if (sbi->nls_io) 155 seq_printf(seq, ",iocharset=%s", sbi->nls_io->charset); 156 if (sbi->s_quiet) 157 seq_printf(seq, ",quiet"); 158 return 0; 159 } 160 161 static struct inode *hfs_alloc_inode(struct super_block *sb) 162 { 163 struct hfs_inode_info *i; 164 165 i = kmem_cache_alloc(hfs_inode_cachep, GFP_KERNEL); 166 return i ? &i->vfs_inode : NULL; 167 } 168 169 static void hfs_i_callback(struct rcu_head *head) 170 { 171 struct inode *inode = container_of(head, struct inode, i_rcu); 172 kmem_cache_free(hfs_inode_cachep, HFS_I(inode)); 173 } 174 175 static void hfs_destroy_inode(struct inode *inode) 176 { 177 call_rcu(&inode->i_rcu, hfs_i_callback); 178 } 179 180 static const struct super_operations hfs_super_operations = { 181 .alloc_inode = hfs_alloc_inode, 182 .destroy_inode = hfs_destroy_inode, 183 .write_inode = hfs_write_inode, 184 .evict_inode = hfs_evict_inode, 185 .put_super = hfs_put_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 pr_err("uid requires an argument\n"); 257 return 0; 258 } 259 hsb->s_uid = make_kuid(current_user_ns(), (uid_t)tmp); 260 if (!uid_valid(hsb->s_uid)) { 261 pr_err("invalid uid %d\n", tmp); 262 return 0; 263 } 264 break; 265 case opt_gid: 266 if (match_int(&args[0], &tmp)) { 267 pr_err("gid requires an argument\n"); 268 return 0; 269 } 270 hsb->s_gid = make_kgid(current_user_ns(), (gid_t)tmp); 271 if (!gid_valid(hsb->s_gid)) { 272 pr_err("invalid gid %d\n", tmp); 273 return 0; 274 } 275 break; 276 case opt_umask: 277 if (match_octal(&args[0], &tmp)) { 278 pr_err("umask requires a value\n"); 279 return 0; 280 } 281 hsb->s_file_umask = (umode_t)tmp; 282 hsb->s_dir_umask = (umode_t)tmp; 283 break; 284 case opt_file_umask: 285 if (match_octal(&args[0], &tmp)) { 286 pr_err("file_umask requires a value\n"); 287 return 0; 288 } 289 hsb->s_file_umask = (umode_t)tmp; 290 break; 291 case opt_dir_umask: 292 if (match_octal(&args[0], &tmp)) { 293 pr_err("dir_umask requires a value\n"); 294 return 0; 295 } 296 hsb->s_dir_umask = (umode_t)tmp; 297 break; 298 case opt_part: 299 if (match_int(&args[0], &hsb->part)) { 300 pr_err("part requires an argument\n"); 301 return 0; 302 } 303 break; 304 case opt_session: 305 if (match_int(&args[0], &hsb->session)) { 306 pr_err("session requires an argument\n"); 307 return 0; 308 } 309 break; 310 case opt_type: 311 if (match_fourchar(&args[0], &hsb->s_type)) { 312 pr_err("type requires a 4 character value\n"); 313 return 0; 314 } 315 break; 316 case opt_creator: 317 if (match_fourchar(&args[0], &hsb->s_creator)) { 318 pr_err("creator requires a 4 character value\n"); 319 return 0; 320 } 321 break; 322 case opt_quiet: 323 hsb->s_quiet = 1; 324 break; 325 case opt_codepage: 326 if (hsb->nls_disk) { 327 pr_err("unable to change codepage\n"); 328 return 0; 329 } 330 p = match_strdup(&args[0]); 331 if (p) 332 hsb->nls_disk = load_nls(p); 333 if (!hsb->nls_disk) { 334 pr_err("unable to load codepage \"%s\"\n", p); 335 kfree(p); 336 return 0; 337 } 338 kfree(p); 339 break; 340 case opt_iocharset: 341 if (hsb->nls_io) { 342 pr_err("unable to change iocharset\n"); 343 return 0; 344 } 345 p = match_strdup(&args[0]); 346 if (p) 347 hsb->nls_io = load_nls(p); 348 if (!hsb->nls_io) { 349 pr_err("unable to load iocharset \"%s\"\n", p); 350 kfree(p); 351 return 0; 352 } 353 kfree(p); 354 break; 355 default: 356 return 0; 357 } 358 } 359 360 if (hsb->nls_disk && !hsb->nls_io) { 361 hsb->nls_io = load_nls_default(); 362 if (!hsb->nls_io) { 363 pr_err("unable to load default iocharset\n"); 364 return 0; 365 } 366 } 367 hsb->s_dir_umask &= 0777; 368 hsb->s_file_umask &= 0577; 369 370 return 1; 371 } 372 373 /* 374 * hfs_read_super() 375 * 376 * This is the function that is responsible for mounting an HFS 377 * filesystem. It performs all the tasks necessary to get enough data 378 * from the disk to read the root inode. This includes parsing the 379 * mount options, dealing with Macintosh partitions, reading the 380 * superblock and the allocation bitmap blocks, calling 381 * hfs_btree_init() to get the necessary data about the extents and 382 * catalog B-trees and, finally, reading the root inode into memory. 383 */ 384 static int hfs_fill_super(struct super_block *sb, void *data, int silent) 385 { 386 struct hfs_sb_info *sbi; 387 struct hfs_find_data fd; 388 hfs_cat_rec rec; 389 struct inode *root_inode; 390 int res; 391 392 sbi = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL); 393 if (!sbi) 394 return -ENOMEM; 395 396 sbi->sb = sb; 397 sb->s_fs_info = sbi; 398 spin_lock_init(&sbi->work_lock); 399 INIT_DELAYED_WORK(&sbi->mdb_work, flush_mdb); 400 401 res = -EINVAL; 402 if (!parse_options((char *)data, sbi)) { 403 pr_err("unable to parse mount options\n"); 404 goto bail; 405 } 406 407 sb->s_op = &hfs_super_operations; 408 sb->s_flags |= MS_NODIRATIME; 409 mutex_init(&sbi->bitmap_lock); 410 411 res = hfs_mdb_get(sb); 412 if (res) { 413 if (!silent) 414 pr_warn("can't find a HFS filesystem on dev %s\n", 415 hfs_mdb_name(sb)); 416 res = -EINVAL; 417 goto bail; 418 } 419 420 /* try to get the root inode */ 421 res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd); 422 if (res) 423 goto bail_no_root; 424 res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd); 425 if (!res) { 426 if (fd.entrylength > sizeof(rec) || fd.entrylength < 0) { 427 res = -EIO; 428 goto bail; 429 } 430 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength); 431 } 432 if (res) { 433 hfs_find_exit(&fd); 434 goto bail_no_root; 435 } 436 res = -EINVAL; 437 root_inode = hfs_iget(sb, &fd.search_key->cat, &rec); 438 hfs_find_exit(&fd); 439 if (!root_inode) 440 goto bail_no_root; 441 442 sb->s_d_op = &hfs_dentry_operations; 443 res = -ENOMEM; 444 sb->s_root = d_make_root(root_inode); 445 if (!sb->s_root) 446 goto bail_no_root; 447 448 /* everything's okay */ 449 return 0; 450 451 bail_no_root: 452 pr_err("get root inode failed\n"); 453 bail: 454 hfs_mdb_put(sb); 455 return res; 456 } 457 458 static struct dentry *hfs_mount(struct file_system_type *fs_type, 459 int flags, const char *dev_name, void *data) 460 { 461 return mount_bdev(fs_type, flags, dev_name, data, hfs_fill_super); 462 } 463 464 static struct file_system_type hfs_fs_type = { 465 .owner = THIS_MODULE, 466 .name = "hfs", 467 .mount = hfs_mount, 468 .kill_sb = kill_block_super, 469 .fs_flags = FS_REQUIRES_DEV, 470 }; 471 MODULE_ALIAS_FS("hfs"); 472 473 static void hfs_init_once(void *p) 474 { 475 struct hfs_inode_info *i = p; 476 477 inode_init_once(&i->vfs_inode); 478 } 479 480 static int __init init_hfs_fs(void) 481 { 482 int err; 483 484 hfs_inode_cachep = kmem_cache_create("hfs_inode_cache", 485 sizeof(struct hfs_inode_info), 0, SLAB_HWCACHE_ALIGN, 486 hfs_init_once); 487 if (!hfs_inode_cachep) 488 return -ENOMEM; 489 err = register_filesystem(&hfs_fs_type); 490 if (err) 491 kmem_cache_destroy(hfs_inode_cachep); 492 return err; 493 } 494 495 static void __exit exit_hfs_fs(void) 496 { 497 unregister_filesystem(&hfs_fs_type); 498 499 /* 500 * Make sure all delayed rcu free inodes are flushed before we 501 * destroy cache. 502 */ 503 rcu_barrier(); 504 kmem_cache_destroy(hfs_inode_cachep); 505 } 506 507 module_init(init_hfs_fs) 508 module_exit(exit_hfs_fs) 509