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_module() and cleanup_module(). 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/config.h> 16 #include <linux/module.h> 17 #include <linux/blkdev.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/vfs.h> 24 25 #include "hfs_fs.h" 26 #include "btree.h" 27 28 static kmem_cache_t *hfs_inode_cachep; 29 30 MODULE_LICENSE("GPL"); 31 32 /* 33 * hfs_write_super() 34 * 35 * Description: 36 * This function is called by the VFS only. When the filesystem 37 * is mounted r/w it updates the MDB on disk. 38 * Input Variable(s): 39 * struct super_block *sb: Pointer to the hfs superblock 40 * Output Variable(s): 41 * NONE 42 * Returns: 43 * void 44 * Preconditions: 45 * 'sb' points to a "valid" (struct super_block). 46 * Postconditions: 47 * The MDB is marked 'unsuccessfully unmounted' by clearing bit 8 of drAtrb 48 * (hfs_put_super() must set this flag!). Some MDB fields are updated 49 * and the MDB buffer is written to disk by calling hfs_mdb_commit(). 50 */ 51 static void hfs_write_super(struct super_block *sb) 52 { 53 sb->s_dirt = 0; 54 if (sb->s_flags & MS_RDONLY) 55 return; 56 /* sync everything to the buffers */ 57 hfs_mdb_commit(sb); 58 } 59 60 /* 61 * hfs_put_super() 62 * 63 * This is the put_super() entry in the super_operations structure for 64 * HFS filesystems. The purpose is to release the resources 65 * associated with the superblock sb. 66 */ 67 static void hfs_put_super(struct super_block *sb) 68 { 69 hfs_mdb_close(sb); 70 /* release the MDB's resources */ 71 hfs_mdb_put(sb); 72 } 73 74 /* 75 * hfs_statfs() 76 * 77 * This is the statfs() entry in the super_operations structure for 78 * HFS filesystems. The purpose is to return various data about the 79 * filesystem. 80 * 81 * changed f_files/f_ffree to reflect the fs_ablock/free_ablocks. 82 */ 83 static int hfs_statfs(struct super_block *sb, struct kstatfs *buf) 84 { 85 buf->f_type = HFS_SUPER_MAGIC; 86 buf->f_bsize = sb->s_blocksize; 87 buf->f_blocks = (u32)HFS_SB(sb)->fs_ablocks * HFS_SB(sb)->fs_div; 88 buf->f_bfree = (u32)HFS_SB(sb)->free_ablocks * HFS_SB(sb)->fs_div; 89 buf->f_bavail = buf->f_bfree; 90 buf->f_files = HFS_SB(sb)->fs_ablocks; 91 buf->f_ffree = HFS_SB(sb)->free_ablocks; 92 buf->f_namelen = HFS_NAMELEN; 93 94 return 0; 95 } 96 97 static int hfs_remount(struct super_block *sb, int *flags, char *data) 98 { 99 *flags |= MS_NODIRATIME; 100 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 101 return 0; 102 if (!(*flags & MS_RDONLY)) { 103 if (!(HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) { 104 printk("HFS-fs warning: Filesystem was not cleanly unmounted, " 105 "running fsck.hfs is recommended. leaving read-only.\n"); 106 sb->s_flags |= MS_RDONLY; 107 *flags |= MS_RDONLY; 108 } else if (HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_SLOCK)) { 109 printk("HFS-fs: Filesystem is marked locked, leaving read-only.\n"); 110 sb->s_flags |= MS_RDONLY; 111 *flags |= MS_RDONLY; 112 } 113 } 114 return 0; 115 } 116 117 static int hfs_show_options(struct seq_file *seq, struct vfsmount *mnt) 118 { 119 struct hfs_sb_info *sbi = HFS_SB(mnt->mnt_sb); 120 121 if (sbi->s_creator != cpu_to_be32(0x3f3f3f3f)) 122 seq_printf(seq, ",creator=%.4s", (char *)&sbi->s_creator); 123 if (sbi->s_type != cpu_to_be32(0x3f3f3f3f)) 124 seq_printf(seq, ",type=%.4s", (char *)&sbi->s_type); 125 seq_printf(seq, ",uid=%u,gid=%u", sbi->s_uid, sbi->s_gid); 126 if (sbi->s_file_umask != 0133) 127 seq_printf(seq, ",file_umask=%o", sbi->s_file_umask); 128 if (sbi->s_dir_umask != 0022) 129 seq_printf(seq, ",dir_umask=%o", sbi->s_dir_umask); 130 if (sbi->part >= 0) 131 seq_printf(seq, ",part=%u", sbi->part); 132 if (sbi->session >= 0) 133 seq_printf(seq, ",session=%u", sbi->session); 134 if (sbi->nls_disk) 135 seq_printf(seq, ",codepage=%s", sbi->nls_disk->charset); 136 if (sbi->nls_io) 137 seq_printf(seq, ",iocharset=%s", sbi->nls_io->charset); 138 if (sbi->s_quiet) 139 seq_printf(seq, ",quiet"); 140 return 0; 141 } 142 143 static struct inode *hfs_alloc_inode(struct super_block *sb) 144 { 145 struct hfs_inode_info *i; 146 147 i = kmem_cache_alloc(hfs_inode_cachep, SLAB_KERNEL); 148 return i ? &i->vfs_inode : NULL; 149 } 150 151 static void hfs_destroy_inode(struct inode *inode) 152 { 153 kmem_cache_free(hfs_inode_cachep, HFS_I(inode)); 154 } 155 156 static struct super_operations hfs_super_operations = { 157 .alloc_inode = hfs_alloc_inode, 158 .destroy_inode = hfs_destroy_inode, 159 .write_inode = hfs_write_inode, 160 .clear_inode = hfs_clear_inode, 161 .put_super = hfs_put_super, 162 .write_super = hfs_write_super, 163 .statfs = hfs_statfs, 164 .remount_fs = hfs_remount, 165 .show_options = hfs_show_options, 166 }; 167 168 enum { 169 opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask, 170 opt_part, opt_session, opt_type, opt_creator, opt_quiet, 171 opt_codepage, opt_iocharset, 172 opt_err 173 }; 174 175 static match_table_t tokens = { 176 { opt_uid, "uid=%u" }, 177 { opt_gid, "gid=%u" }, 178 { opt_umask, "umask=%o" }, 179 { opt_file_umask, "file_umask=%o" }, 180 { opt_dir_umask, "dir_umask=%o" }, 181 { opt_part, "part=%u" }, 182 { opt_session, "session=%u" }, 183 { opt_type, "type=%s" }, 184 { opt_creator, "creator=%s" }, 185 { opt_quiet, "quiet" }, 186 { opt_codepage, "codepage=%s" }, 187 { opt_iocharset, "iocharset=%s" }, 188 { opt_err, NULL } 189 }; 190 191 static inline int match_fourchar(substring_t *arg, u32 *result) 192 { 193 if (arg->to - arg->from != 4) 194 return -EINVAL; 195 memcpy(result, arg->from, 4); 196 return 0; 197 } 198 199 /* 200 * parse_options() 201 * 202 * adapted from linux/fs/msdos/inode.c written 1992,93 by Werner Almesberger 203 * This function is called by hfs_read_super() to parse the mount options. 204 */ 205 static int parse_options(char *options, struct hfs_sb_info *hsb) 206 { 207 char *p; 208 substring_t args[MAX_OPT_ARGS]; 209 int tmp, token; 210 211 /* initialize the sb with defaults */ 212 hsb->s_uid = current->uid; 213 hsb->s_gid = current->gid; 214 hsb->s_file_umask = 0133; 215 hsb->s_dir_umask = 0022; 216 hsb->s_type = hsb->s_creator = cpu_to_be32(0x3f3f3f3f); /* == '????' */ 217 hsb->s_quiet = 0; 218 hsb->part = -1; 219 hsb->session = -1; 220 221 if (!options) 222 return 1; 223 224 while ((p = strsep(&options, ",")) != NULL) { 225 if (!*p) 226 continue; 227 228 token = match_token(p, tokens, args); 229 switch (token) { 230 case opt_uid: 231 if (match_int(&args[0], &tmp)) { 232 printk("HFS: uid requires an argument\n"); 233 return 0; 234 } 235 hsb->s_uid = (uid_t)tmp; 236 break; 237 case opt_gid: 238 if (match_int(&args[0], &tmp)) { 239 printk("HFS: gid requires an argument\n"); 240 return 0; 241 } 242 hsb->s_gid = (gid_t)tmp; 243 break; 244 case opt_umask: 245 if (match_octal(&args[0], &tmp)) { 246 printk("HFS: umask requires a value\n"); 247 return 0; 248 } 249 hsb->s_file_umask = (umode_t)tmp; 250 hsb->s_dir_umask = (umode_t)tmp; 251 break; 252 case opt_file_umask: 253 if (match_octal(&args[0], &tmp)) { 254 printk("HFS: file_umask requires a value\n"); 255 return 0; 256 } 257 hsb->s_file_umask = (umode_t)tmp; 258 break; 259 case opt_dir_umask: 260 if (match_octal(&args[0], &tmp)) { 261 printk("HFS: dir_umask requires a value\n"); 262 return 0; 263 } 264 hsb->s_dir_umask = (umode_t)tmp; 265 break; 266 case opt_part: 267 if (match_int(&args[0], &hsb->part)) { 268 printk("HFS: part requires an argument\n"); 269 return 0; 270 } 271 break; 272 case opt_session: 273 if (match_int(&args[0], &hsb->session)) { 274 printk("HFS: session requires an argument\n"); 275 return 0; 276 } 277 break; 278 case opt_type: 279 if (match_fourchar(&args[0], &hsb->s_type)) { 280 printk("HFS+-fs: type requires a 4 character value\n"); 281 return 0; 282 } 283 break; 284 case opt_creator: 285 if (match_fourchar(&args[0], &hsb->s_creator)) { 286 printk("HFS+-fs: creator requires a 4 character value\n"); 287 return 0; 288 } 289 break; 290 case opt_quiet: 291 hsb->s_quiet = 1; 292 break; 293 case opt_codepage: 294 if (hsb->nls_disk) { 295 printk("HFS+-fs: unable to change codepage\n"); 296 return 0; 297 } 298 p = match_strdup(&args[0]); 299 hsb->nls_disk = load_nls(p); 300 if (!hsb->nls_disk) { 301 printk("HFS+-fs: unable to load codepage \"%s\"\n", p); 302 kfree(p); 303 return 0; 304 } 305 kfree(p); 306 break; 307 case opt_iocharset: 308 if (hsb->nls_io) { 309 printk("HFS: unable to change iocharset\n"); 310 return 0; 311 } 312 p = match_strdup(&args[0]); 313 hsb->nls_io = load_nls(p); 314 if (!hsb->nls_io) { 315 printk("HFS: unable to load iocharset \"%s\"\n", p); 316 kfree(p); 317 return 0; 318 } 319 kfree(p); 320 break; 321 default: 322 return 0; 323 } 324 } 325 326 if (hsb->nls_disk && !hsb->nls_io) { 327 hsb->nls_io = load_nls_default(); 328 if (!hsb->nls_io) { 329 printk("HFS: unable to load default iocharset\n"); 330 return 0; 331 } 332 } 333 hsb->s_dir_umask &= 0777; 334 hsb->s_file_umask &= 0577; 335 336 return 1; 337 } 338 339 /* 340 * hfs_read_super() 341 * 342 * This is the function that is responsible for mounting an HFS 343 * filesystem. It performs all the tasks necessary to get enough data 344 * from the disk to read the root inode. This includes parsing the 345 * mount options, dealing with Macintosh partitions, reading the 346 * superblock and the allocation bitmap blocks, calling 347 * hfs_btree_init() to get the necessary data about the extents and 348 * catalog B-trees and, finally, reading the root inode into memory. 349 */ 350 static int hfs_fill_super(struct super_block *sb, void *data, int silent) 351 { 352 struct hfs_sb_info *sbi; 353 struct hfs_find_data fd; 354 hfs_cat_rec rec; 355 struct inode *root_inode; 356 int res; 357 358 sbi = kmalloc(sizeof(struct hfs_sb_info), GFP_KERNEL); 359 if (!sbi) 360 return -ENOMEM; 361 sb->s_fs_info = sbi; 362 memset(sbi, 0, sizeof(struct hfs_sb_info)); 363 INIT_HLIST_HEAD(&sbi->rsrc_inodes); 364 365 res = -EINVAL; 366 if (!parse_options((char *)data, sbi)) { 367 hfs_warn("hfs_fs: unable to parse mount options.\n"); 368 goto bail; 369 } 370 371 sb->s_op = &hfs_super_operations; 372 sb->s_flags |= MS_NODIRATIME; 373 init_MUTEX(&sbi->bitmap_lock); 374 375 res = hfs_mdb_get(sb); 376 if (res) { 377 if (!silent) 378 hfs_warn("VFS: Can't find a HFS filesystem on dev %s.\n", 379 hfs_mdb_name(sb)); 380 res = -EINVAL; 381 goto bail; 382 } 383 384 /* try to get the root inode */ 385 hfs_find_init(HFS_SB(sb)->cat_tree, &fd); 386 res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd); 387 if (!res) 388 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength); 389 if (res) { 390 hfs_find_exit(&fd); 391 goto bail_no_root; 392 } 393 root_inode = hfs_iget(sb, &fd.search_key->cat, &rec); 394 hfs_find_exit(&fd); 395 if (!root_inode) 396 goto bail_no_root; 397 398 sb->s_root = d_alloc_root(root_inode); 399 if (!sb->s_root) 400 goto bail_iput; 401 402 sb->s_root->d_op = &hfs_dentry_operations; 403 404 /* everything's okay */ 405 return 0; 406 407 bail_iput: 408 iput(root_inode); 409 bail_no_root: 410 hfs_warn("hfs_fs: get root inode failed.\n"); 411 bail: 412 hfs_mdb_put(sb); 413 return res; 414 } 415 416 static struct super_block *hfs_get_sb(struct file_system_type *fs_type, 417 int flags, const char *dev_name, void *data) 418 { 419 return get_sb_bdev(fs_type, flags, dev_name, data, hfs_fill_super); 420 } 421 422 static struct file_system_type hfs_fs_type = { 423 .owner = THIS_MODULE, 424 .name = "hfs", 425 .get_sb = hfs_get_sb, 426 .kill_sb = kill_block_super, 427 .fs_flags = FS_REQUIRES_DEV, 428 }; 429 430 static void hfs_init_once(void *p, kmem_cache_t *cachep, unsigned long flags) 431 { 432 struct hfs_inode_info *i = p; 433 434 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == SLAB_CTOR_CONSTRUCTOR) 435 inode_init_once(&i->vfs_inode); 436 } 437 438 static int __init init_hfs_fs(void) 439 { 440 int err; 441 442 hfs_inode_cachep = kmem_cache_create("hfs_inode_cache", 443 sizeof(struct hfs_inode_info), 0, SLAB_HWCACHE_ALIGN, 444 hfs_init_once, NULL); 445 if (!hfs_inode_cachep) 446 return -ENOMEM; 447 err = register_filesystem(&hfs_fs_type); 448 if (err) 449 kmem_cache_destroy(hfs_inode_cachep); 450 return err; 451 } 452 453 static void __exit exit_hfs_fs(void) 454 { 455 unregister_filesystem(&hfs_fs_type); 456 if (kmem_cache_destroy(hfs_inode_cachep)) 457 printk(KERN_INFO "hfs_inode_cache: not all structures were freed\n"); 458 } 459 460 module_init(init_hfs_fs) 461 module_exit(exit_hfs_fs) 462