| 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) |