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/backing-dev.h> 18 #include <linux/mount.h> 19 #include <linux/init.h> 20 #include <linux/nls.h> 21 #include <linux/parser.h> 22 #include <linux/seq_file.h> 23 #include <linux/slab.h> 24 #include <linux/vfs.h> 25 26 #include "hfs_fs.h" 27 #include "btree.h" 28 29 static struct kmem_cache *hfs_inode_cachep; 30 31 MODULE_LICENSE("GPL"); 32 33 static int hfs_sync_fs(struct super_block *sb, int wait) 34 { 35 hfs_mdb_commit(sb); 36 return 0; 37 } 38 39 /* 40 * hfs_put_super() 41 * 42 * This is the put_super() entry in the super_operations structure for 43 * HFS filesystems. The purpose is to release the resources 44 * associated with the superblock sb. 45 */ 46 static void hfs_put_super(struct super_block *sb) 47 { 48 cancel_delayed_work_sync(&HFS_SB(sb)->mdb_work); 49 hfs_mdb_close(sb); 50 /* release the MDB's resources */ 51 hfs_mdb_put(sb); 52 } 53 54 static void flush_mdb(struct work_struct *work) 55 { 56 struct hfs_sb_info *sbi; 57 struct super_block *sb; 58 59 sbi = container_of(work, struct hfs_sb_info, mdb_work.work); 60 sb = sbi->sb; 61 62 spin_lock(&sbi->work_lock); 63 sbi->work_queued = 0; 64 spin_unlock(&sbi->work_lock); 65 66 hfs_mdb_commit(sb); 67 } 68 69 void hfs_mark_mdb_dirty(struct super_block *sb) 70 { 71 struct hfs_sb_info *sbi = HFS_SB(sb); 72 unsigned long delay; 73 74 if (sb->s_flags & MS_RDONLY) 75 return; 76 77 spin_lock(&sbi->work_lock); 78 if (!sbi->work_queued) { 79 delay = msecs_to_jiffies(dirty_writeback_interval * 10); 80 queue_delayed_work(system_long_wq, &sbi->mdb_work, delay); 81 sbi->work_queued = 1; 82 } 83 spin_unlock(&sbi->work_lock); 84 } 85 86 /* 87 * hfs_statfs() 88 * 89 * This is the statfs() entry in the super_operations structure for 90 * HFS filesystems. The purpose is to return various data about the 91 * filesystem. 92 * 93 * changed f_files/f_ffree to reflect the fs_ablock/free_ablocks. 94 */ 95 static int hfs_statfs(struct dentry *dentry, struct kstatfs *buf) 96 { 97 struct super_block *sb = dentry->d_sb; 98 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 99 100 buf->f_type = HFS_SUPER_MAGIC; 101 buf->f_bsize = sb->s_blocksize; 102 buf->f_blocks = (u32)HFS_SB(sb)->fs_ablocks * HFS_SB(sb)->fs_div; 103 buf->f_bfree = (u32)HFS_SB(sb)->free_ablocks * HFS_SB(sb)->fs_div; 104 buf->f_bavail = buf->f_bfree; 105 buf->f_files = HFS_SB(sb)->fs_ablocks; 106 buf->f_ffree = HFS_SB(sb)->free_ablocks; 107 buf->f_fsid.val[0] = (u32)id; 108 buf->f_fsid.val[1] = (u32)(id >> 32); 109 buf->f_namelen = HFS_NAMELEN; 110 111 return 0; 112 } 113 114 static int hfs_remount(struct super_block *sb, int *flags, char *data) 115 { 116 sync_filesystem(sb); 117 *flags |= MS_NODIRATIME; 118 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 119 return 0; 120 if (!(*flags & MS_RDONLY)) { 121 if (!(HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) { 122 pr_warn("filesystem was not cleanly unmounted, running fsck.hfs is recommended. leaving read-only.\n"); 123 sb->s_flags |= MS_RDONLY; 124 *flags |= MS_RDONLY; 125 } else if (HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_SLOCK)) { 126 pr_warn("filesystem is marked locked, leaving read-only.\n"); 127 sb->s_flags |= MS_RDONLY; 128 *flags |= MS_RDONLY; 129 } 130 } 131 return 0; 132 } 133 134 static int hfs_show_options(struct seq_file *seq, struct dentry *root) 135 { 136 struct hfs_sb_info *sbi = HFS_SB(root->d_sb); 137 138 if (sbi->s_creator != cpu_to_be32(0x3f3f3f3f)) 139 seq_show_option_n(seq, "creator", (char *)&sbi->s_creator, 4); 140 if (sbi->s_type != cpu_to_be32(0x3f3f3f3f)) 141 seq_show_option_n(seq, "type", (char *)&sbi->s_type, 4); 142 seq_printf(seq, ",uid=%u,gid=%u", 143 from_kuid_munged(&init_user_ns, sbi->s_uid), 144 from_kgid_munged(&init_user_ns, sbi->s_gid)); 145 if (sbi->s_file_umask != 0133) 146 seq_printf(seq, ",file_umask=%o", sbi->s_file_umask); 147 if (sbi->s_dir_umask != 0022) 148 seq_printf(seq, ",dir_umask=%o", sbi->s_dir_umask); 149 if (sbi->part >= 0) 150 seq_printf(seq, ",part=%u", sbi->part); 151 if (sbi->session >= 0) 152 seq_printf(seq, ",session=%u", sbi->session); 153 if (sbi->nls_disk) 154 seq_printf(seq, ",codepage=%s", sbi->nls_disk->charset); 155 if (sbi->nls_io) 156 seq_printf(seq, ",iocharset=%s", sbi->nls_io->charset); 157 if (sbi->s_quiet) 158 seq_printf(seq, ",quiet"); 159 return 0; 160 } 161 162 static struct inode *hfs_alloc_inode(struct super_block *sb) 163 { 164 struct hfs_inode_info *i; 165 166 i = kmem_cache_alloc(hfs_inode_cachep, GFP_KERNEL); 167 return i ? &i->vfs_inode : NULL; 168 } 169 170 static void hfs_i_callback(struct rcu_head *head) 171 { 172 struct inode *inode = container_of(head, struct inode, i_rcu); 173 kmem_cache_free(hfs_inode_cachep, HFS_I(inode)); 174 } 175 176 static void hfs_destroy_inode(struct inode *inode) 177 { 178 call_rcu(&inode->i_rcu, hfs_i_callback); 179 } 180 181 static const struct super_operations hfs_super_operations = { 182 .alloc_inode = hfs_alloc_inode, 183 .destroy_inode = hfs_destroy_inode, 184 .write_inode = hfs_write_inode, 185 .evict_inode = hfs_evict_inode, 186 .put_super = hfs_put_super, 187 .sync_fs = hfs_sync_fs, 188 .statfs = hfs_statfs, 189 .remount_fs = hfs_remount, 190 .show_options = hfs_show_options, 191 }; 192 193 enum { 194 opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask, 195 opt_part, opt_session, opt_type, opt_creator, opt_quiet, 196 opt_codepage, opt_iocharset, 197 opt_err 198 }; 199 200 static const match_table_t tokens = { 201 { opt_uid, "uid=%u" }, 202 { opt_gid, "gid=%u" }, 203 { opt_umask, "umask=%o" }, 204 { opt_file_umask, "file_umask=%o" }, 205 { opt_dir_umask, "dir_umask=%o" }, 206 { opt_part, "part=%u" }, 207 { opt_session, "session=%u" }, 208 { opt_type, "type=%s" }, 209 { opt_creator, "creator=%s" }, 210 { opt_quiet, "quiet" }, 211 { opt_codepage, "codepage=%s" }, 212 { opt_iocharset, "iocharset=%s" }, 213 { opt_err, NULL } 214 }; 215 216 static inline int match_fourchar(substring_t *arg, u32 *result) 217 { 218 if (arg->to - arg->from != 4) 219 return -EINVAL; 220 memcpy(result, arg->from, 4); 221 return 0; 222 } 223 224 /* 225 * parse_options() 226 * 227 * adapted from linux/fs/msdos/inode.c written 1992,93 by Werner Almesberger 228 * This function is called by hfs_read_super() to parse the mount options. 229 */ 230 static int parse_options(char *options, struct hfs_sb_info *hsb) 231 { 232 char *p; 233 substring_t args[MAX_OPT_ARGS]; 234 int tmp, token; 235 236 /* initialize the sb with defaults */ 237 hsb->s_uid = current_uid(); 238 hsb->s_gid = current_gid(); 239 hsb->s_file_umask = 0133; 240 hsb->s_dir_umask = 0022; 241 hsb->s_type = hsb->s_creator = cpu_to_be32(0x3f3f3f3f); /* == '????' */ 242 hsb->s_quiet = 0; 243 hsb->part = -1; 244 hsb->session = -1; 245 246 if (!options) 247 return 1; 248 249 while ((p = strsep(&options, ",")) != NULL) { 250 if (!*p) 251 continue; 252 253 token = match_token(p, tokens, args); 254 switch (token) { 255 case opt_uid: 256 if (match_int(&args[0], &tmp)) { 257 pr_err("uid requires an argument\n"); 258 return 0; 259 } 260 hsb->s_uid = make_kuid(current_user_ns(), (uid_t)tmp); 261 if (!uid_valid(hsb->s_uid)) { 262 pr_err("invalid uid %d\n", tmp); 263 return 0; 264 } 265 break; 266 case opt_gid: 267 if (match_int(&args[0], &tmp)) { 268 pr_err("gid requires an argument\n"); 269 return 0; 270 } 271 hsb->s_gid = make_kgid(current_user_ns(), (gid_t)tmp); 272 if (!gid_valid(hsb->s_gid)) { 273 pr_err("invalid gid %d\n", tmp); 274 return 0; 275 } 276 break; 277 case opt_umask: 278 if (match_octal(&args[0], &tmp)) { 279 pr_err("umask requires a value\n"); 280 return 0; 281 } 282 hsb->s_file_umask = (umode_t)tmp; 283 hsb->s_dir_umask = (umode_t)tmp; 284 break; 285 case opt_file_umask: 286 if (match_octal(&args[0], &tmp)) { 287 pr_err("file_umask requires a value\n"); 288 return 0; 289 } 290 hsb->s_file_umask = (umode_t)tmp; 291 break; 292 case opt_dir_umask: 293 if (match_octal(&args[0], &tmp)) { 294 pr_err("dir_umask requires a value\n"); 295 return 0; 296 } 297 hsb->s_dir_umask = (umode_t)tmp; 298 break; 299 case opt_part: 300 if (match_int(&args[0], &hsb->part)) { 301 pr_err("part requires an argument\n"); 302 return 0; 303 } 304 break; 305 case opt_session: 306 if (match_int(&args[0], &hsb->session)) { 307 pr_err("session requires an argument\n"); 308 return 0; 309 } 310 break; 311 case opt_type: 312 if (match_fourchar(&args[0], &hsb->s_type)) { 313 pr_err("type requires a 4 character value\n"); 314 return 0; 315 } 316 break; 317 case opt_creator: 318 if (match_fourchar(&args[0], &hsb->s_creator)) { 319 pr_err("creator requires a 4 character value\n"); 320 return 0; 321 } 322 break; 323 case opt_quiet: 324 hsb->s_quiet = 1; 325 break; 326 case opt_codepage: 327 if (hsb->nls_disk) { 328 pr_err("unable to change codepage\n"); 329 return 0; 330 } 331 p = match_strdup(&args[0]); 332 if (p) 333 hsb->nls_disk = load_nls(p); 334 if (!hsb->nls_disk) { 335 pr_err("unable to load codepage \"%s\"\n", p); 336 kfree(p); 337 return 0; 338 } 339 kfree(p); 340 break; 341 case opt_iocharset: 342 if (hsb->nls_io) { 343 pr_err("unable to change iocharset\n"); 344 return 0; 345 } 346 p = match_strdup(&args[0]); 347 if (p) 348 hsb->nls_io = load_nls(p); 349 if (!hsb->nls_io) { 350 pr_err("unable to load iocharset \"%s\"\n", p); 351 kfree(p); 352 return 0; 353 } 354 kfree(p); 355 break; 356 default: 357 return 0; 358 } 359 } 360 361 if (hsb->nls_disk && !hsb->nls_io) { 362 hsb->nls_io = load_nls_default(); 363 if (!hsb->nls_io) { 364 pr_err("unable to load default iocharset\n"); 365 return 0; 366 } 367 } 368 hsb->s_dir_umask &= 0777; 369 hsb->s_file_umask &= 0577; 370 371 return 1; 372 } 373 374 /* 375 * hfs_read_super() 376 * 377 * This is the function that is responsible for mounting an HFS 378 * filesystem. It performs all the tasks necessary to get enough data 379 * from the disk to read the root inode. This includes parsing the 380 * mount options, dealing with Macintosh partitions, reading the 381 * superblock and the allocation bitmap blocks, calling 382 * hfs_btree_init() to get the necessary data about the extents and 383 * catalog B-trees and, finally, reading the root inode into memory. 384 */ 385 static int hfs_fill_super(struct super_block *sb, void *data, int silent) 386 { 387 struct hfs_sb_info *sbi; 388 struct hfs_find_data fd; 389 hfs_cat_rec rec; 390 struct inode *root_inode; 391 int res; 392 393 sbi = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL); 394 if (!sbi) 395 return -ENOMEM; 396 397 sbi->sb = sb; 398 sb->s_fs_info = sbi; 399 spin_lock_init(&sbi->work_lock); 400 INIT_DELAYED_WORK(&sbi->mdb_work, flush_mdb); 401 402 res = -EINVAL; 403 if (!parse_options((char *)data, sbi)) { 404 pr_err("unable to parse mount options\n"); 405 goto bail; 406 } 407 408 sb->s_op = &hfs_super_operations; 409 sb->s_flags |= MS_NODIRATIME; 410 mutex_init(&sbi->bitmap_lock); 411 412 res = hfs_mdb_get(sb); 413 if (res) { 414 if (!silent) 415 pr_warn("can't find a HFS filesystem on dev %s\n", 416 hfs_mdb_name(sb)); 417 res = -EINVAL; 418 goto bail; 419 } 420 421 /* try to get the root inode */ 422 res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd); 423 if (res) 424 goto bail_no_root; 425 res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd); 426 if (!res) { 427 if (fd.entrylength > sizeof(rec) || fd.entrylength < 0) { 428 res = -EIO; 429 goto bail; 430 } 431 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength); 432 } 433 if (res) { 434 hfs_find_exit(&fd); 435 goto bail_no_root; 436 } 437 res = -EINVAL; 438 root_inode = hfs_iget(sb, &fd.search_key->cat, &rec); 439 hfs_find_exit(&fd); 440 if (!root_inode) 441 goto bail_no_root; 442 443 sb->s_d_op = &hfs_dentry_operations; 444 res = -ENOMEM; 445 sb->s_root = d_make_root(root_inode); 446 if (!sb->s_root) 447 goto bail_no_root; 448 449 /* everything's okay */ 450 return 0; 451 452 bail_no_root: 453 pr_err("get root inode failed\n"); 454 bail: 455 hfs_mdb_put(sb); 456 return res; 457 } 458 459 static struct dentry *hfs_mount(struct file_system_type *fs_type, 460 int flags, const char *dev_name, void *data) 461 { 462 return mount_bdev(fs_type, flags, dev_name, data, hfs_fill_super); 463 } 464 465 static struct file_system_type hfs_fs_type = { 466 .owner = THIS_MODULE, 467 .name = "hfs", 468 .mount = hfs_mount, 469 .kill_sb = kill_block_super, 470 .fs_flags = FS_REQUIRES_DEV, 471 }; 472 MODULE_ALIAS_FS("hfs"); 473 474 static void hfs_init_once(void *p) 475 { 476 struct hfs_inode_info *i = p; 477 478 inode_init_once(&i->vfs_inode); 479 } 480 481 static int __init init_hfs_fs(void) 482 { 483 int err; 484 485 hfs_inode_cachep = kmem_cache_create("hfs_inode_cache", 486 sizeof(struct hfs_inode_info), 0, SLAB_HWCACHE_ALIGN, 487 hfs_init_once); 488 if (!hfs_inode_cachep) 489 return -ENOMEM; 490 err = register_filesystem(&hfs_fs_type); 491 if (err) 492 kmem_cache_destroy(hfs_inode_cachep); 493 return err; 494 } 495 496 static void __exit exit_hfs_fs(void) 497 { 498 unregister_filesystem(&hfs_fs_type); 499 500 /* 501 * Make sure all delayed rcu free inodes are flushed before we 502 * destroy cache. 503 */ 504 rcu_barrier(); 505 kmem_cache_destroy(hfs_inode_cachep); 506 } 507 508 module_init(init_hfs_fs) 509 module_exit(exit_hfs_fs) 510