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 pr_warn("filesystem was not cleanly unmounted, running fsck.hfs is recommended. leaving read-only.\n"); 121 sb->s_flags |= MS_RDONLY; 122 *flags |= MS_RDONLY; 123 } else if (HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_SLOCK)) { 124 pr_warn("filesystem is marked locked, leaving read-only.\n"); 125 sb->s_flags |= MS_RDONLY; 126 *flags |= MS_RDONLY; 127 } 128 } 129 return 0; 130 } 131 132 static int hfs_show_options(struct seq_file *seq, struct dentry *root) 133 { 134 struct hfs_sb_info *sbi = HFS_SB(root->d_sb); 135 136 if (sbi->s_creator != cpu_to_be32(0x3f3f3f3f)) 137 seq_printf(seq, ",creator=%.4s", (char *)&sbi->s_creator); 138 if (sbi->s_type != cpu_to_be32(0x3f3f3f3f)) 139 seq_printf(seq, ",type=%.4s", (char *)&sbi->s_type); 140 seq_printf(seq, ",uid=%u,gid=%u", 141 from_kuid_munged(&init_user_ns, sbi->s_uid), 142 from_kgid_munged(&init_user_ns, sbi->s_gid)); 143 if (sbi->s_file_umask != 0133) 144 seq_printf(seq, ",file_umask=%o", sbi->s_file_umask); 145 if (sbi->s_dir_umask != 0022) 146 seq_printf(seq, ",dir_umask=%o", sbi->s_dir_umask); 147 if (sbi->part >= 0) 148 seq_printf(seq, ",part=%u", sbi->part); 149 if (sbi->session >= 0) 150 seq_printf(seq, ",session=%u", sbi->session); 151 if (sbi->nls_disk) 152 seq_printf(seq, ",codepage=%s", sbi->nls_disk->charset); 153 if (sbi->nls_io) 154 seq_printf(seq, ",iocharset=%s", sbi->nls_io->charset); 155 if (sbi->s_quiet) 156 seq_printf(seq, ",quiet"); 157 return 0; 158 } 159 160 static struct inode *hfs_alloc_inode(struct super_block *sb) 161 { 162 struct hfs_inode_info *i; 163 164 i = kmem_cache_alloc(hfs_inode_cachep, GFP_KERNEL); 165 return i ? &i->vfs_inode : NULL; 166 } 167 168 static void hfs_i_callback(struct rcu_head *head) 169 { 170 struct inode *inode = container_of(head, struct inode, i_rcu); 171 kmem_cache_free(hfs_inode_cachep, HFS_I(inode)); 172 } 173 174 static void hfs_destroy_inode(struct inode *inode) 175 { 176 call_rcu(&inode->i_rcu, hfs_i_callback); 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 .evict_inode = hfs_evict_inode, 184 .put_super = hfs_put_super, 185 .sync_fs = hfs_sync_fs, 186 .statfs = hfs_statfs, 187 .remount_fs = hfs_remount, 188 .show_options = hfs_show_options, 189 }; 190 191 enum { 192 opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask, 193 opt_part, opt_session, opt_type, opt_creator, opt_quiet, 194 opt_codepage, opt_iocharset, 195 opt_err 196 }; 197 198 static const match_table_t tokens = { 199 { opt_uid, "uid=%u" }, 200 { opt_gid, "gid=%u" }, 201 { opt_umask, "umask=%o" }, 202 { opt_file_umask, "file_umask=%o" }, 203 { opt_dir_umask, "dir_umask=%o" }, 204 { opt_part, "part=%u" }, 205 { opt_session, "session=%u" }, 206 { opt_type, "type=%s" }, 207 { opt_creator, "creator=%s" }, 208 { opt_quiet, "quiet" }, 209 { opt_codepage, "codepage=%s" }, 210 { opt_iocharset, "iocharset=%s" }, 211 { opt_err, NULL } 212 }; 213 214 static inline int match_fourchar(substring_t *arg, u32 *result) 215 { 216 if (arg->to - arg->from != 4) 217 return -EINVAL; 218 memcpy(result, arg->from, 4); 219 return 0; 220 } 221 222 /* 223 * parse_options() 224 * 225 * adapted from linux/fs/msdos/inode.c written 1992,93 by Werner Almesberger 226 * This function is called by hfs_read_super() to parse the mount options. 227 */ 228 static int parse_options(char *options, struct hfs_sb_info *hsb) 229 { 230 char *p; 231 substring_t args[MAX_OPT_ARGS]; 232 int tmp, token; 233 234 /* initialize the sb with defaults */ 235 hsb->s_uid = current_uid(); 236 hsb->s_gid = current_gid(); 237 hsb->s_file_umask = 0133; 238 hsb->s_dir_umask = 0022; 239 hsb->s_type = hsb->s_creator = cpu_to_be32(0x3f3f3f3f); /* == '????' */ 240 hsb->s_quiet = 0; 241 hsb->part = -1; 242 hsb->session = -1; 243 244 if (!options) 245 return 1; 246 247 while ((p = strsep(&options, ",")) != NULL) { 248 if (!*p) 249 continue; 250 251 token = match_token(p, tokens, args); 252 switch (token) { 253 case opt_uid: 254 if (match_int(&args[0], &tmp)) { 255 pr_err("uid requires an argument\n"); 256 return 0; 257 } 258 hsb->s_uid = make_kuid(current_user_ns(), (uid_t)tmp); 259 if (!uid_valid(hsb->s_uid)) { 260 pr_err("invalid uid %d\n", tmp); 261 return 0; 262 } 263 break; 264 case opt_gid: 265 if (match_int(&args[0], &tmp)) { 266 pr_err("gid requires an argument\n"); 267 return 0; 268 } 269 hsb->s_gid = make_kgid(current_user_ns(), (gid_t)tmp); 270 if (!gid_valid(hsb->s_gid)) { 271 pr_err("invalid gid %d\n", tmp); 272 return 0; 273 } 274 break; 275 case opt_umask: 276 if (match_octal(&args[0], &tmp)) { 277 pr_err("umask requires a value\n"); 278 return 0; 279 } 280 hsb->s_file_umask = (umode_t)tmp; 281 hsb->s_dir_umask = (umode_t)tmp; 282 break; 283 case opt_file_umask: 284 if (match_octal(&args[0], &tmp)) { 285 pr_err("file_umask requires a value\n"); 286 return 0; 287 } 288 hsb->s_file_umask = (umode_t)tmp; 289 break; 290 case opt_dir_umask: 291 if (match_octal(&args[0], &tmp)) { 292 pr_err("dir_umask requires a value\n"); 293 return 0; 294 } 295 hsb->s_dir_umask = (umode_t)tmp; 296 break; 297 case opt_part: 298 if (match_int(&args[0], &hsb->part)) { 299 pr_err("part requires an argument\n"); 300 return 0; 301 } 302 break; 303 case opt_session: 304 if (match_int(&args[0], &hsb->session)) { 305 pr_err("session requires an argument\n"); 306 return 0; 307 } 308 break; 309 case opt_type: 310 if (match_fourchar(&args[0], &hsb->s_type)) { 311 pr_err("type requires a 4 character value\n"); 312 return 0; 313 } 314 break; 315 case opt_creator: 316 if (match_fourchar(&args[0], &hsb->s_creator)) { 317 pr_err("creator requires a 4 character value\n"); 318 return 0; 319 } 320 break; 321 case opt_quiet: 322 hsb->s_quiet = 1; 323 break; 324 case opt_codepage: 325 if (hsb->nls_disk) { 326 pr_err("unable to change codepage\n"); 327 return 0; 328 } 329 p = match_strdup(&args[0]); 330 if (p) 331 hsb->nls_disk = load_nls(p); 332 if (!hsb->nls_disk) { 333 pr_err("unable to load codepage \"%s\"\n", p); 334 kfree(p); 335 return 0; 336 } 337 kfree(p); 338 break; 339 case opt_iocharset: 340 if (hsb->nls_io) { 341 pr_err("unable to change iocharset\n"); 342 return 0; 343 } 344 p = match_strdup(&args[0]); 345 if (p) 346 hsb->nls_io = load_nls(p); 347 if (!hsb->nls_io) { 348 pr_err("unable to load iocharset \"%s\"\n", p); 349 kfree(p); 350 return 0; 351 } 352 kfree(p); 353 break; 354 default: 355 return 0; 356 } 357 } 358 359 if (hsb->nls_disk && !hsb->nls_io) { 360 hsb->nls_io = load_nls_default(); 361 if (!hsb->nls_io) { 362 pr_err("unable to load default iocharset\n"); 363 return 0; 364 } 365 } 366 hsb->s_dir_umask &= 0777; 367 hsb->s_file_umask &= 0577; 368 369 return 1; 370 } 371 372 /* 373 * hfs_read_super() 374 * 375 * This is the function that is responsible for mounting an HFS 376 * filesystem. It performs all the tasks necessary to get enough data 377 * from the disk to read the root inode. This includes parsing the 378 * mount options, dealing with Macintosh partitions, reading the 379 * superblock and the allocation bitmap blocks, calling 380 * hfs_btree_init() to get the necessary data about the extents and 381 * catalog B-trees and, finally, reading the root inode into memory. 382 */ 383 static int hfs_fill_super(struct super_block *sb, void *data, int silent) 384 { 385 struct hfs_sb_info *sbi; 386 struct hfs_find_data fd; 387 hfs_cat_rec rec; 388 struct inode *root_inode; 389 int res; 390 391 sbi = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL); 392 if (!sbi) 393 return -ENOMEM; 394 395 sbi->sb = sb; 396 sb->s_fs_info = sbi; 397 spin_lock_init(&sbi->work_lock); 398 INIT_DELAYED_WORK(&sbi->mdb_work, flush_mdb); 399 400 res = -EINVAL; 401 if (!parse_options((char *)data, sbi)) { 402 pr_err("unable to parse mount options\n"); 403 goto bail; 404 } 405 406 sb->s_op = &hfs_super_operations; 407 sb->s_flags |= MS_NODIRATIME; 408 mutex_init(&sbi->bitmap_lock); 409 410 res = hfs_mdb_get(sb); 411 if (res) { 412 if (!silent) 413 pr_warn("can't find a HFS filesystem on dev %s\n", 414 hfs_mdb_name(sb)); 415 res = -EINVAL; 416 goto bail; 417 } 418 419 /* try to get the root inode */ 420 res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd); 421 if (res) 422 goto bail_no_root; 423 res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd); 424 if (!res) { 425 if (fd.entrylength > sizeof(rec) || fd.entrylength < 0) { 426 res = -EIO; 427 goto bail; 428 } 429 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength); 430 } 431 if (res) { 432 hfs_find_exit(&fd); 433 goto bail_no_root; 434 } 435 res = -EINVAL; 436 root_inode = hfs_iget(sb, &fd.search_key->cat, &rec); 437 hfs_find_exit(&fd); 438 if (!root_inode) 439 goto bail_no_root; 440 441 sb->s_d_op = &hfs_dentry_operations; 442 res = -ENOMEM; 443 sb->s_root = d_make_root(root_inode); 444 if (!sb->s_root) 445 goto bail_no_root; 446 447 /* everything's okay */ 448 return 0; 449 450 bail_no_root: 451 pr_err("get root inode failed\n"); 452 bail: 453 hfs_mdb_put(sb); 454 return res; 455 } 456 457 static struct dentry *hfs_mount(struct file_system_type *fs_type, 458 int flags, const char *dev_name, void *data) 459 { 460 return mount_bdev(fs_type, flags, dev_name, data, hfs_fill_super); 461 } 462 463 static struct file_system_type hfs_fs_type = { 464 .owner = THIS_MODULE, 465 .name = "hfs", 466 .mount = hfs_mount, 467 .kill_sb = kill_block_super, 468 .fs_flags = FS_REQUIRES_DEV, 469 }; 470 MODULE_ALIAS_FS("hfs"); 471 472 static void hfs_init_once(void *p) 473 { 474 struct hfs_inode_info *i = p; 475 476 inode_init_once(&i->vfs_inode); 477 } 478 479 static int __init init_hfs_fs(void) 480 { 481 int err; 482 483 hfs_inode_cachep = kmem_cache_create("hfs_inode_cache", 484 sizeof(struct hfs_inode_info), 0, SLAB_HWCACHE_ALIGN, 485 hfs_init_once); 486 if (!hfs_inode_cachep) 487 return -ENOMEM; 488 err = register_filesystem(&hfs_fs_type); 489 if (err) 490 kmem_cache_destroy(hfs_inode_cachep); 491 return err; 492 } 493 494 static void __exit exit_hfs_fs(void) 495 { 496 unregister_filesystem(&hfs_fs_type); 497 498 /* 499 * Make sure all delayed rcu free inodes are flushed before we 500 * destroy cache. 501 */ 502 rcu_barrier(); 503 kmem_cache_destroy(hfs_inode_cachep); 504 } 505 506 module_init(init_hfs_fs) 507 module_exit(exit_hfs_fs) 508