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 hfs_sync_fs(struct super_block * sb,int wait)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 */ hfs_put_super(struct super_block * sb)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 flush_mdb(struct work_struct * work)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 hfs_mark_mdb_dirty(struct super_block * sb)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_rdonly(sb)) 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 */ hfs_statfs(struct dentry * dentry,struct kstatfs * buf)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 = u64_to_fsid(id); 108 buf->f_namelen = HFS_NAMELEN; 109 110 return 0; 111 } 112 hfs_remount(struct super_block * sb,int * flags,char * data)113 static int hfs_remount(struct super_block *sb, int *flags, char *data) 114 { 115 sync_filesystem(sb); 116 *flags |= SB_NODIRATIME; 117 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) 118 return 0; 119 if (!(*flags & SB_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 |= SB_RDONLY; 123 *flags |= SB_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 |= SB_RDONLY; 127 *flags |= SB_RDONLY; 128 } 129 } 130 return 0; 131 } 132 hfs_show_options(struct seq_file * seq,struct dentry * root)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_show_option_n(seq, "creator", (char *)&sbi->s_creator, 4); 139 if (sbi->s_type != cpu_to_be32(0x3f3f3f3f)) 140 seq_show_option_n(seq, "type", (char *)&sbi->s_type, 4); 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 hfs_alloc_inode(struct super_block * sb)161 static struct inode *hfs_alloc_inode(struct super_block *sb) 162 { 163 struct hfs_inode_info *i; 164 165 i = alloc_inode_sb(sb, hfs_inode_cachep, GFP_KERNEL); 166 return i ? &i->vfs_inode : NULL; 167 } 168 hfs_free_inode(struct inode * inode)169 static void hfs_free_inode(struct inode *inode) 170 { 171 kmem_cache_free(hfs_inode_cachep, HFS_I(inode)); 172 } 173 174 static const struct super_operations hfs_super_operations = { 175 .alloc_inode = hfs_alloc_inode, 176 .free_inode = hfs_free_inode, 177 .write_inode = hfs_write_inode, 178 .evict_inode = hfs_evict_inode, 179 .put_super = hfs_put_super, 180 .sync_fs = hfs_sync_fs, 181 .statfs = hfs_statfs, 182 .remount_fs = hfs_remount, 183 .show_options = hfs_show_options, 184 }; 185 186 enum { 187 opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask, 188 opt_part, opt_session, opt_type, opt_creator, opt_quiet, 189 opt_codepage, opt_iocharset, 190 opt_err 191 }; 192 193 static const match_table_t tokens = { 194 { opt_uid, "uid=%u" }, 195 { opt_gid, "gid=%u" }, 196 { opt_umask, "umask=%o" }, 197 { opt_file_umask, "file_umask=%o" }, 198 { opt_dir_umask, "dir_umask=%o" }, 199 { opt_part, "part=%u" }, 200 { opt_session, "session=%u" }, 201 { opt_type, "type=%s" }, 202 { opt_creator, "creator=%s" }, 203 { opt_quiet, "quiet" }, 204 { opt_codepage, "codepage=%s" }, 205 { opt_iocharset, "iocharset=%s" }, 206 { opt_err, NULL } 207 }; 208 match_fourchar(substring_t * arg,u32 * result)209 static inline int match_fourchar(substring_t *arg, u32 *result) 210 { 211 if (arg->to - arg->from != 4) 212 return -EINVAL; 213 memcpy(result, arg->from, 4); 214 return 0; 215 } 216 217 /* 218 * parse_options() 219 * 220 * adapted from linux/fs/msdos/inode.c written 1992,93 by Werner Almesberger 221 * This function is called by hfs_read_super() to parse the mount options. 222 */ parse_options(char * options,struct hfs_sb_info * hsb)223 static int parse_options(char *options, struct hfs_sb_info *hsb) 224 { 225 char *p; 226 substring_t args[MAX_OPT_ARGS]; 227 int tmp, token; 228 229 /* initialize the sb with defaults */ 230 hsb->s_uid = current_uid(); 231 hsb->s_gid = current_gid(); 232 hsb->s_file_umask = 0133; 233 hsb->s_dir_umask = 0022; 234 hsb->s_type = hsb->s_creator = cpu_to_be32(0x3f3f3f3f); /* == '????' */ 235 hsb->s_quiet = 0; 236 hsb->part = -1; 237 hsb->session = -1; 238 239 if (!options) 240 return 1; 241 242 while ((p = strsep(&options, ",")) != NULL) { 243 if (!*p) 244 continue; 245 246 token = match_token(p, tokens, args); 247 switch (token) { 248 case opt_uid: 249 if (match_int(&args[0], &tmp)) { 250 pr_err("uid requires an argument\n"); 251 return 0; 252 } 253 hsb->s_uid = make_kuid(current_user_ns(), (uid_t)tmp); 254 if (!uid_valid(hsb->s_uid)) { 255 pr_err("invalid uid %d\n", tmp); 256 return 0; 257 } 258 break; 259 case opt_gid: 260 if (match_int(&args[0], &tmp)) { 261 pr_err("gid requires an argument\n"); 262 return 0; 263 } 264 hsb->s_gid = make_kgid(current_user_ns(), (gid_t)tmp); 265 if (!gid_valid(hsb->s_gid)) { 266 pr_err("invalid gid %d\n", tmp); 267 return 0; 268 } 269 break; 270 case opt_umask: 271 if (match_octal(&args[0], &tmp)) { 272 pr_err("umask requires a value\n"); 273 return 0; 274 } 275 hsb->s_file_umask = (umode_t)tmp; 276 hsb->s_dir_umask = (umode_t)tmp; 277 break; 278 case opt_file_umask: 279 if (match_octal(&args[0], &tmp)) { 280 pr_err("file_umask requires a value\n"); 281 return 0; 282 } 283 hsb->s_file_umask = (umode_t)tmp; 284 break; 285 case opt_dir_umask: 286 if (match_octal(&args[0], &tmp)) { 287 pr_err("dir_umask requires a value\n"); 288 return 0; 289 } 290 hsb->s_dir_umask = (umode_t)tmp; 291 break; 292 case opt_part: 293 if (match_int(&args[0], &hsb->part)) { 294 pr_err("part requires an argument\n"); 295 return 0; 296 } 297 break; 298 case opt_session: 299 if (match_int(&args[0], &hsb->session)) { 300 pr_err("session requires an argument\n"); 301 return 0; 302 } 303 break; 304 case opt_type: 305 if (match_fourchar(&args[0], &hsb->s_type)) { 306 pr_err("type requires a 4 character value\n"); 307 return 0; 308 } 309 break; 310 case opt_creator: 311 if (match_fourchar(&args[0], &hsb->s_creator)) { 312 pr_err("creator requires a 4 character value\n"); 313 return 0; 314 } 315 break; 316 case opt_quiet: 317 hsb->s_quiet = 1; 318 break; 319 case opt_codepage: 320 if (hsb->nls_disk) { 321 pr_err("unable to change codepage\n"); 322 return 0; 323 } 324 p = match_strdup(&args[0]); 325 if (p) 326 hsb->nls_disk = load_nls(p); 327 if (!hsb->nls_disk) { 328 pr_err("unable to load codepage \"%s\"\n", p); 329 kfree(p); 330 return 0; 331 } 332 kfree(p); 333 break; 334 case opt_iocharset: 335 if (hsb->nls_io) { 336 pr_err("unable to change iocharset\n"); 337 return 0; 338 } 339 p = match_strdup(&args[0]); 340 if (p) 341 hsb->nls_io = load_nls(p); 342 if (!hsb->nls_io) { 343 pr_err("unable to load iocharset \"%s\"\n", p); 344 kfree(p); 345 return 0; 346 } 347 kfree(p); 348 break; 349 default: 350 return 0; 351 } 352 } 353 354 if (hsb->nls_disk && !hsb->nls_io) { 355 hsb->nls_io = load_nls_default(); 356 if (!hsb->nls_io) { 357 pr_err("unable to load default iocharset\n"); 358 return 0; 359 } 360 } 361 hsb->s_dir_umask &= 0777; 362 hsb->s_file_umask &= 0577; 363 364 return 1; 365 } 366 367 /* 368 * hfs_read_super() 369 * 370 * This is the function that is responsible for mounting an HFS 371 * filesystem. It performs all the tasks necessary to get enough data 372 * from the disk to read the root inode. This includes parsing the 373 * mount options, dealing with Macintosh partitions, reading the 374 * superblock and the allocation bitmap blocks, calling 375 * hfs_btree_init() to get the necessary data about the extents and 376 * catalog B-trees and, finally, reading the root inode into memory. 377 */ hfs_fill_super(struct super_block * sb,void * data,int silent)378 static int hfs_fill_super(struct super_block *sb, void *data, int silent) 379 { 380 struct hfs_sb_info *sbi; 381 struct hfs_find_data fd; 382 hfs_cat_rec rec; 383 struct inode *root_inode; 384 int res; 385 386 sbi = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL); 387 if (!sbi) 388 return -ENOMEM; 389 390 sbi->sb = sb; 391 sb->s_fs_info = sbi; 392 spin_lock_init(&sbi->work_lock); 393 INIT_DELAYED_WORK(&sbi->mdb_work, flush_mdb); 394 395 res = -EINVAL; 396 if (!parse_options((char *)data, sbi)) { 397 pr_err("unable to parse mount options\n"); 398 goto bail; 399 } 400 401 sb->s_op = &hfs_super_operations; 402 sb->s_xattr = hfs_xattr_handlers; 403 sb->s_flags |= SB_NODIRATIME; 404 mutex_init(&sbi->bitmap_lock); 405 406 res = hfs_mdb_get(sb); 407 if (res) { 408 if (!silent) 409 pr_warn("can't find a HFS filesystem on dev %s\n", 410 hfs_mdb_name(sb)); 411 res = -EINVAL; 412 goto bail; 413 } 414 415 /* try to get the root inode */ 416 res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd); 417 if (res) 418 goto bail_no_root; 419 res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd); 420 if (!res) { 421 if (fd.entrylength != sizeof(rec.dir)) { 422 res = -EIO; 423 goto bail_hfs_find; 424 } 425 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength); 426 if (rec.type != HFS_CDR_DIR) 427 res = -EIO; 428 } 429 if (res) 430 goto bail_hfs_find; 431 res = -EINVAL; 432 root_inode = hfs_iget(sb, &fd.search_key->cat, &rec); 433 hfs_find_exit(&fd); 434 if (!root_inode) 435 goto bail_no_root; 436 437 sb->s_d_op = &hfs_dentry_operations; 438 res = -ENOMEM; 439 sb->s_root = d_make_root(root_inode); 440 if (!sb->s_root) 441 goto bail_no_root; 442 443 /* everything's okay */ 444 return 0; 445 446 bail_hfs_find: 447 hfs_find_exit(&fd); 448 bail_no_root: 449 pr_err("get root inode failed\n"); 450 bail: 451 hfs_mdb_put(sb); 452 return res; 453 } 454 hfs_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * data)455 static struct dentry *hfs_mount(struct file_system_type *fs_type, 456 int flags, const char *dev_name, void *data) 457 { 458 return mount_bdev(fs_type, flags, dev_name, data, hfs_fill_super); 459 } 460 461 static struct file_system_type hfs_fs_type = { 462 .owner = THIS_MODULE, 463 .name = "hfs", 464 .mount = hfs_mount, 465 .kill_sb = kill_block_super, 466 .fs_flags = FS_REQUIRES_DEV, 467 }; 468 MODULE_ALIAS_FS("hfs"); 469 hfs_init_once(void * p)470 static void hfs_init_once(void *p) 471 { 472 struct hfs_inode_info *i = p; 473 474 inode_init_once(&i->vfs_inode); 475 } 476 init_hfs_fs(void)477 static int __init init_hfs_fs(void) 478 { 479 int err; 480 481 hfs_inode_cachep = kmem_cache_create("hfs_inode_cache", 482 sizeof(struct hfs_inode_info), 0, 483 SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT, hfs_init_once); 484 if (!hfs_inode_cachep) 485 return -ENOMEM; 486 err = register_filesystem(&hfs_fs_type); 487 if (err) 488 kmem_cache_destroy(hfs_inode_cachep); 489 return err; 490 } 491 exit_hfs_fs(void)492 static void __exit exit_hfs_fs(void) 493 { 494 unregister_filesystem(&hfs_fs_type); 495 496 /* 497 * Make sure all delayed rcu free inodes are flushed before we 498 * destroy cache. 499 */ 500 rcu_barrier(); 501 kmem_cache_destroy(hfs_inode_cachep); 502 } 503 504 module_init(init_hfs_fs) 505 module_exit(exit_hfs_fs) 506