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/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/vfs.h> 23 24#include "hfs_fs.h" 25#include "btree.h" 26 27static struct kmem_cache *hfs_inode_cachep; 28 29MODULE_LICENSE("GPL"); 30 31/* 32 * hfs_write_super() 33 * 34 * Description: 35 * This function is called by the VFS only. When the filesystem 36 * is mounted r/w it updates the MDB on disk. 37 * Input Variable(s): 38 * struct super_block *sb: Pointer to the hfs superblock 39 * Output Variable(s): 40 * NONE 41 * Returns: 42 * void 43 * Preconditions: 44 * 'sb' points to a "valid" (struct super_block). 45 * Postconditions: 46 * The MDB is marked 'unsuccessfully unmounted' by clearing bit 8 of drAtrb 47 * (hfs_put_super() must set this flag!). Some MDB fields are updated 48 * and the MDB buffer is written to disk by calling hfs_mdb_commit(). 49 */ 50static void hfs_write_super(struct super_block *sb) 51{ 52 sb->s_dirt = 0; 53 if (sb->s_flags & MS_RDONLY) 54 return; 55 /* sync everything to the buffers */ 56 hfs_mdb_commit(sb); 57} 58 59/* 60 * hfs_put_super() 61 * 62 * This is the put_super() entry in the super_operations structure for 63 * HFS filesystems. The purpose is to release the resources 64 * associated with the superblock sb. 65 */ 66static void hfs_put_super(struct super_block *sb) 67{ 68 hfs_mdb_close(sb); 69 /* release the MDB's resources */ 70 hfs_mdb_put(sb); 71} 72 73/* 74 * hfs_statfs() 75 * 76 * This is the statfs() entry in the super_operations structure for 77 * HFS filesystems. The purpose is to return various data about the 78 * filesystem. 79 * 80 * changed f_files/f_ffree to reflect the fs_ablock/free_ablocks. 81 */ 82static int hfs_statfs(struct dentry *dentry, struct kstatfs *buf) 83{ 84 struct super_block *sb = dentry->d_sb; 85 86 buf->f_type = HFS_SUPER_MAGIC; 87 buf->f_bsize = sb->s_blocksize; 88 buf->f_blocks = (u32)HFS_SB(sb)->fs_ablocks * HFS_SB(sb)->fs_div; 89 buf->f_bfree = (u32)HFS_SB(sb)->free_ablocks * HFS_SB(sb)->fs_div; 90 buf->f_bavail = buf->f_bfree; 91 buf->f_files = HFS_SB(sb)->fs_ablocks; 92 buf->f_ffree = HFS_SB(sb)->free_ablocks; 93 buf->f_namelen = HFS_NAMELEN; 94 95 return 0; 96} 97 98static int hfs_remount(struct super_block *sb, int *flags, char *data) 99{ 100 *flags |= MS_NODIRATIME; 101 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 102 return 0; 103 if (!(*flags & MS_RDONLY)) { 104 if (!(HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) { 105 printk(KERN_WARNING "hfs: filesystem was not cleanly unmounted, " 106 "running fsck.hfs is recommended. leaving read-only.\n"); 107 /* Foxconn removed start pling 05/31/2010 */ 108 /* Ignore this flag to force writeable */ 109#if 0 110 sb->s_flags |= MS_RDONLY; 111 *flags |= MS_RDONLY; 112#endif 113 /* Foxconn removed end pling 05/31/2010 */ 114 } else if (HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_SLOCK)) { 115 printk(KERN_WARNING "hfs: filesystem is marked locked, leaving read-only.\n"); 116 sb->s_flags |= MS_RDONLY; 117 *flags |= MS_RDONLY; 118 } 119 } 120 return 0; 121} 122 123static int hfs_show_options(struct seq_file *seq, struct vfsmount *mnt) 124{ 125 struct hfs_sb_info *sbi = HFS_SB(mnt->mnt_sb); 126 127 if (sbi->s_creator != cpu_to_be32(0x3f3f3f3f)) 128 seq_printf(seq, ",creator=%.4s", (char *)&sbi->s_creator); 129 if (sbi->s_type != cpu_to_be32(0x3f3f3f3f)) 130 seq_printf(seq, ",type=%.4s", (char *)&sbi->s_type); 131 seq_printf(seq, ",uid=%u,gid=%u", sbi->s_uid, sbi->s_gid); 132 if (sbi->s_file_umask != 0133) 133 seq_printf(seq, ",file_umask=%o", sbi->s_file_umask); 134 if (sbi->s_dir_umask != 0022) 135 seq_printf(seq, ",dir_umask=%o", sbi->s_dir_umask); 136 if (sbi->part >= 0) 137 seq_printf(seq, ",part=%u", sbi->part); 138 if (sbi->session >= 0) 139 seq_printf(seq, ",session=%u", sbi->session); 140 if (sbi->nls_disk) 141 seq_printf(seq, ",codepage=%s", sbi->nls_disk->charset); 142 if (sbi->nls_io) 143 seq_printf(seq, ",iocharset=%s", sbi->nls_io->charset); 144 if (sbi->s_quiet) 145 seq_printf(seq, ",quiet"); 146 return 0; 147} 148 149static struct inode *hfs_alloc_inode(struct super_block *sb) 150{ 151 struct hfs_inode_info *i; 152 153 i = kmem_cache_alloc(hfs_inode_cachep, GFP_KERNEL); 154 return i ? &i->vfs_inode : NULL; 155} 156 157static void hfs_destroy_inode(struct inode *inode) 158{ 159 kmem_cache_free(hfs_inode_cachep, HFS_I(inode)); 160} 161 162static const struct super_operations hfs_super_operations = { 163 .alloc_inode = hfs_alloc_inode, 164 .destroy_inode = hfs_destroy_inode, 165 .write_inode = hfs_write_inode, 166 .clear_inode = hfs_clear_inode, 167 .put_super = hfs_put_super, 168 .write_super = hfs_write_super, 169 .statfs = hfs_statfs, 170 .remount_fs = hfs_remount, 171 .show_options = hfs_show_options, 172}; 173 174enum { 175 opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask, 176 opt_part, opt_session, opt_type, opt_creator, opt_quiet, 177 opt_codepage, opt_iocharset, 178 opt_err 179}; 180 181static match_table_t tokens = { 182 { opt_uid, "uid=%u" }, 183 { opt_gid, "gid=%u" }, 184 { opt_umask, "umask=%o" }, 185 { opt_file_umask, "file_umask=%o" }, 186 { opt_dir_umask, "dir_umask=%o" }, 187 { opt_part, "part=%u" }, 188 { opt_session, "session=%u" }, 189 { opt_type, "type=%s" }, 190 { opt_creator, "creator=%s" }, 191 { opt_quiet, "quiet" }, 192 { opt_codepage, "codepage=%s" }, 193 { opt_iocharset, "iocharset=%s" }, 194 { opt_err, NULL } 195}; 196 197static inline int match_fourchar(substring_t *arg, u32 *result) 198{ 199 if (arg->to - arg->from != 4) 200 return -EINVAL; 201 memcpy(result, arg->from, 4); 202 return 0; 203} 204 205/* 206 * parse_options() 207 * 208 * adapted from linux/fs/msdos/inode.c written 1992,93 by Werner Almesberger 209 * This function is called by hfs_read_super() to parse the mount options. 210 */ 211static int parse_options(char *options, struct hfs_sb_info *hsb) 212{ 213 char *p; 214 substring_t args[MAX_OPT_ARGS]; 215 int tmp, token; 216 217 /* initialize the sb with defaults */ 218 hsb->s_uid = current->uid; 219 hsb->s_gid = current->gid; 220 hsb->s_file_umask = 0133; 221 hsb->s_dir_umask = 0022; 222 hsb->s_type = hsb->s_creator = cpu_to_be32(0x3f3f3f3f); /* == '????' */ 223 hsb->s_quiet = 0; 224 hsb->part = -1; 225 hsb->session = -1; 226 227 if (!options) 228 return 1; 229 230 while ((p = strsep(&options, ",")) != NULL) { 231 if (!*p) 232 continue; 233 234 token = match_token(p, tokens, args); 235 switch (token) { 236 case opt_uid: 237 if (match_int(&args[0], &tmp)) { 238 printk(KERN_ERR "hfs: uid requires an argument\n"); 239 return 0; 240 } 241 hsb->s_uid = (uid_t)tmp; 242 break; 243 case opt_gid: 244 if (match_int(&args[0], &tmp)) { 245 printk(KERN_ERR "hfs: gid requires an argument\n"); 246 return 0; 247 } 248 hsb->s_gid = (gid_t)tmp; 249 break; 250 case opt_umask: 251 if (match_octal(&args[0], &tmp)) { 252 printk(KERN_ERR "hfs: umask requires a value\n"); 253 return 0; 254 } 255 hsb->s_file_umask = (umode_t)tmp; 256 hsb->s_dir_umask = (umode_t)tmp; 257 break; 258 case opt_file_umask: 259 if (match_octal(&args[0], &tmp)) { 260 printk(KERN_ERR "hfs: file_umask requires a value\n"); 261 return 0; 262 } 263 hsb->s_file_umask = (umode_t)tmp; 264 break; 265 case opt_dir_umask: 266 if (match_octal(&args[0], &tmp)) { 267 printk(KERN_ERR "hfs: dir_umask requires a value\n"); 268 return 0; 269 } 270 hsb->s_dir_umask = (umode_t)tmp; 271 break; 272 case opt_part: 273 if (match_int(&args[0], &hsb->part)) { 274 printk(KERN_ERR "hfs: part requires an argument\n"); 275 return 0; 276 } 277 break; 278 case opt_session: 279 if (match_int(&args[0], &hsb->session)) { 280 printk(KERN_ERR "hfs: session requires an argument\n"); 281 return 0; 282 } 283 break; 284 case opt_type: 285 if (match_fourchar(&args[0], &hsb->s_type)) { 286 printk(KERN_ERR "hfs: type requires a 4 character value\n"); 287 return 0; 288 } 289 break; 290 case opt_creator: 291 if (match_fourchar(&args[0], &hsb->s_creator)) { 292 printk(KERN_ERR "hfs: creator requires a 4 character value\n"); 293 return 0; 294 } 295 break; 296 case opt_quiet: 297 hsb->s_quiet = 1; 298 break; 299 case opt_codepage: 300 if (hsb->nls_disk) { 301 printk(KERN_ERR "hfs: unable to change codepage\n"); 302 return 0; 303 } 304 p = match_strdup(&args[0]); 305 hsb->nls_disk = load_nls(p); 306 if (!hsb->nls_disk) { 307 printk(KERN_ERR "hfs: unable to load codepage \"%s\"\n", p); 308 kfree(p); 309 return 0; 310 } 311 kfree(p); 312 break; 313 case opt_iocharset: 314 if (hsb->nls_io) { 315 printk(KERN_ERR "hfs: unable to change iocharset\n"); 316 return 0; 317 } 318 p = match_strdup(&args[0]); 319 hsb->nls_io = load_nls(p); 320 if (!hsb->nls_io) { 321 printk(KERN_ERR "hfs: unable to load iocharset \"%s\"\n", p); 322 kfree(p); 323 return 0; 324 } 325 kfree(p); 326 break; 327 default: 328 return 0; 329 } 330 } 331 332 if (hsb->nls_disk && !hsb->nls_io) { 333 hsb->nls_io = load_nls_default(); 334 if (!hsb->nls_io) { 335 printk(KERN_ERR "hfs: unable to load default iocharset\n"); 336 return 0; 337 } 338 } 339 hsb->s_dir_umask &= 0777; 340 hsb->s_file_umask &= 0577; 341 342 return 1; 343} 344 345/* 346 * hfs_read_super() 347 * 348 * This is the function that is responsible for mounting an HFS 349 * filesystem. It performs all the tasks necessary to get enough data 350 * from the disk to read the root inode. This includes parsing the 351 * mount options, dealing with Macintosh partitions, reading the 352 * superblock and the allocation bitmap blocks, calling 353 * hfs_btree_init() to get the necessary data about the extents and 354 * catalog B-trees and, finally, reading the root inode into memory. 355 */ 356static int hfs_fill_super(struct super_block *sb, void *data, int silent) 357{ 358 struct hfs_sb_info *sbi; 359 struct hfs_find_data fd; 360 hfs_cat_rec rec; 361 struct inode *root_inode; 362 int res; 363 364 sbi = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL); 365 if (!sbi) 366 return -ENOMEM; 367 sb->s_fs_info = sbi; 368 INIT_HLIST_HEAD(&sbi->rsrc_inodes); 369 370 res = -EINVAL; 371 if (!parse_options((char *)data, sbi)) { 372 printk(KERN_ERR "hfs: unable to parse mount options.\n"); 373 goto bail; 374 } 375 376 sb->s_op = &hfs_super_operations; 377 sb->s_flags |= MS_NODIRATIME; 378 init_MUTEX(&sbi->bitmap_lock); 379 380 res = hfs_mdb_get(sb); 381 if (res) { 382 if (!silent) 383 printk(KERN_WARNING "hfs: can't find a HFS filesystem on dev %s.\n", 384 hfs_mdb_name(sb)); 385 res = -EINVAL; 386 goto bail; 387 } 388 389 /* try to get the root inode */ 390 hfs_find_init(HFS_SB(sb)->cat_tree, &fd); 391 res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd); 392 if (!res) 393 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength); 394 if (res) { 395 hfs_find_exit(&fd); 396 goto bail_no_root; 397 } 398 res = -EINVAL; 399 root_inode = hfs_iget(sb, &fd.search_key->cat, &rec); 400 hfs_find_exit(&fd); 401 if (!root_inode) 402 goto bail_no_root; 403 404 res = -ENOMEM; 405 sb->s_root = d_alloc_root(root_inode); 406 if (!sb->s_root) 407 goto bail_iput; 408 409 sb->s_root->d_op = &hfs_dentry_operations; 410 411 /* everything's okay */ 412 return 0; 413 414bail_iput: 415 iput(root_inode); 416bail_no_root: 417 printk(KERN_ERR "hfs: get root inode failed.\n"); 418bail: 419 hfs_mdb_put(sb); 420 return res; 421} 422 423static int hfs_get_sb(struct file_system_type *fs_type, 424 int flags, const char *dev_name, void *data, 425 struct vfsmount *mnt) 426{ 427 return get_sb_bdev(fs_type, flags, dev_name, data, hfs_fill_super, mnt); 428} 429 430static struct file_system_type hfs_fs_type = { 431 .owner = THIS_MODULE, 432 .name = "hfs", 433 .get_sb = hfs_get_sb, 434 .kill_sb = kill_block_super, 435 .fs_flags = FS_REQUIRES_DEV, 436}; 437 438static void hfs_init_once(void *p, struct kmem_cache *cachep, unsigned long flags) 439{ 440 struct hfs_inode_info *i = p; 441 442 inode_init_once(&i->vfs_inode); 443} 444 445static int __init init_hfs_fs(void) 446{ 447 int err; 448 449 hfs_inode_cachep = kmem_cache_create("hfs_inode_cache", 450 sizeof(struct hfs_inode_info), 0, SLAB_HWCACHE_ALIGN, 451 hfs_init_once, NULL); 452 if (!hfs_inode_cachep) 453 return -ENOMEM; 454 err = register_filesystem(&hfs_fs_type); 455 if (err) 456 kmem_cache_destroy(hfs_inode_cachep); 457 return err; 458} 459 460static void __exit exit_hfs_fs(void) 461{ 462 unregister_filesystem(&hfs_fs_type); 463 kmem_cache_destroy(hfs_inode_cachep); 464} 465 466module_init(init_hfs_fs) 467module_exit(exit_hfs_fs) 468