1 /* 2 * linux/fs/ext2/super.c 3 * 4 * Copyright (C) 1992, 1993, 1994, 1995 5 * Remy Card (card@masi.ibp.fr) 6 * Laboratoire MASI - Institut Blaise Pascal 7 * Universite Pierre et Marie Curie (Paris VI) 8 * 9 * from 10 * 11 * linux/fs/minix/inode.c 12 * 13 * Copyright (C) 1991, 1992 Linus Torvalds 14 * 15 * Big-endian to little-endian byte-swapping/bitmaps by 16 * David S. Miller (davem@caip.rutgers.edu), 1995 17 */ 18 19 #include <linux/module.h> 20 #include <linux/string.h> 21 #include <linux/fs.h> 22 #include <linux/slab.h> 23 #include <linux/init.h> 24 #include <linux/blkdev.h> 25 #include <linux/parser.h> 26 #include <linux/random.h> 27 #include <linux/buffer_head.h> 28 #include <linux/exportfs.h> 29 #include <linux/vfs.h> 30 #include <linux/seq_file.h> 31 #include <linux/mount.h> 32 #include <linux/log2.h> 33 #include <linux/quotaops.h> 34 #include <asm/uaccess.h> 35 #include "ext2.h" 36 #include "xattr.h" 37 #include "acl.h" 38 39 static void ext2_sync_super(struct super_block *sb, 40 struct ext2_super_block *es, int wait); 41 static int ext2_remount (struct super_block * sb, int * flags, char * data); 42 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf); 43 static int ext2_sync_fs(struct super_block *sb, int wait); 44 static int ext2_freeze(struct super_block *sb); 45 static int ext2_unfreeze(struct super_block *sb); 46 47 void ext2_error(struct super_block *sb, const char *function, 48 const char *fmt, ...) 49 { 50 struct va_format vaf; 51 va_list args; 52 struct ext2_sb_info *sbi = EXT2_SB(sb); 53 struct ext2_super_block *es = sbi->s_es; 54 55 if (!(sb->s_flags & MS_RDONLY)) { 56 spin_lock(&sbi->s_lock); 57 sbi->s_mount_state |= EXT2_ERROR_FS; 58 es->s_state |= cpu_to_le16(EXT2_ERROR_FS); 59 spin_unlock(&sbi->s_lock); 60 ext2_sync_super(sb, es, 1); 61 } 62 63 va_start(args, fmt); 64 65 vaf.fmt = fmt; 66 vaf.va = &args; 67 68 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n", 69 sb->s_id, function, &vaf); 70 71 va_end(args); 72 73 if (test_opt(sb, ERRORS_PANIC)) 74 panic("EXT2-fs: panic from previous error\n"); 75 if (test_opt(sb, ERRORS_RO)) { 76 ext2_msg(sb, KERN_CRIT, 77 "error: remounting filesystem read-only"); 78 sb->s_flags |= MS_RDONLY; 79 } 80 } 81 82 void ext2_msg(struct super_block *sb, const char *prefix, 83 const char *fmt, ...) 84 { 85 struct va_format vaf; 86 va_list args; 87 88 va_start(args, fmt); 89 90 vaf.fmt = fmt; 91 vaf.va = &args; 92 93 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf); 94 95 va_end(args); 96 } 97 98 /* 99 * This must be called with sbi->s_lock held. 100 */ 101 void ext2_update_dynamic_rev(struct super_block *sb) 102 { 103 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 104 105 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) 106 return; 107 108 ext2_msg(sb, KERN_WARNING, 109 "warning: updating to rev %d because of " 110 "new feature flag, running e2fsck is recommended", 111 EXT2_DYNAMIC_REV); 112 113 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); 114 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); 115 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); 116 /* leave es->s_feature_*compat flags alone */ 117 /* es->s_uuid will be set by e2fsck if empty */ 118 119 /* 120 * The rest of the superblock fields should be zero, and if not it 121 * means they are likely already in use, so leave them alone. We 122 * can leave it up to e2fsck to clean up any inconsistencies there. 123 */ 124 } 125 126 static void ext2_put_super (struct super_block * sb) 127 { 128 int db_count; 129 int i; 130 struct ext2_sb_info *sbi = EXT2_SB(sb); 131 132 dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 133 134 ext2_xattr_put_super(sb); 135 if (!(sb->s_flags & MS_RDONLY)) { 136 struct ext2_super_block *es = sbi->s_es; 137 138 spin_lock(&sbi->s_lock); 139 es->s_state = cpu_to_le16(sbi->s_mount_state); 140 spin_unlock(&sbi->s_lock); 141 ext2_sync_super(sb, es, 1); 142 } 143 db_count = sbi->s_gdb_count; 144 for (i = 0; i < db_count; i++) 145 if (sbi->s_group_desc[i]) 146 brelse (sbi->s_group_desc[i]); 147 kfree(sbi->s_group_desc); 148 kfree(sbi->s_debts); 149 percpu_counter_destroy(&sbi->s_freeblocks_counter); 150 percpu_counter_destroy(&sbi->s_freeinodes_counter); 151 percpu_counter_destroy(&sbi->s_dirs_counter); 152 brelse (sbi->s_sbh); 153 sb->s_fs_info = NULL; 154 kfree(sbi->s_blockgroup_lock); 155 kfree(sbi); 156 } 157 158 static struct kmem_cache * ext2_inode_cachep; 159 160 static struct inode *ext2_alloc_inode(struct super_block *sb) 161 { 162 struct ext2_inode_info *ei; 163 ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL); 164 if (!ei) 165 return NULL; 166 ei->i_block_alloc_info = NULL; 167 ei->vfs_inode.i_version = 1; 168 #ifdef CONFIG_QUOTA 169 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot)); 170 #endif 171 172 return &ei->vfs_inode; 173 } 174 175 static void ext2_i_callback(struct rcu_head *head) 176 { 177 struct inode *inode = container_of(head, struct inode, i_rcu); 178 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 179 } 180 181 static void ext2_destroy_inode(struct inode *inode) 182 { 183 call_rcu(&inode->i_rcu, ext2_i_callback); 184 } 185 186 static void init_once(void *foo) 187 { 188 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 189 190 rwlock_init(&ei->i_meta_lock); 191 #ifdef CONFIG_EXT2_FS_XATTR 192 init_rwsem(&ei->xattr_sem); 193 #endif 194 mutex_init(&ei->truncate_mutex); 195 #ifdef CONFIG_FS_DAX 196 init_rwsem(&ei->dax_sem); 197 #endif 198 inode_init_once(&ei->vfs_inode); 199 } 200 201 static int __init init_inodecache(void) 202 { 203 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 204 sizeof(struct ext2_inode_info), 205 0, (SLAB_RECLAIM_ACCOUNT| 206 SLAB_MEM_SPREAD), 207 init_once); 208 if (ext2_inode_cachep == NULL) 209 return -ENOMEM; 210 return 0; 211 } 212 213 static void destroy_inodecache(void) 214 { 215 /* 216 * Make sure all delayed rcu free inodes are flushed before we 217 * destroy cache. 218 */ 219 rcu_barrier(); 220 kmem_cache_destroy(ext2_inode_cachep); 221 } 222 223 static int ext2_show_options(struct seq_file *seq, struct dentry *root) 224 { 225 struct super_block *sb = root->d_sb; 226 struct ext2_sb_info *sbi = EXT2_SB(sb); 227 struct ext2_super_block *es = sbi->s_es; 228 unsigned long def_mount_opts; 229 230 spin_lock(&sbi->s_lock); 231 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 232 233 if (sbi->s_sb_block != 1) 234 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 235 if (test_opt(sb, MINIX_DF)) 236 seq_puts(seq, ",minixdf"); 237 if (test_opt(sb, GRPID)) 238 seq_puts(seq, ",grpid"); 239 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 240 seq_puts(seq, ",nogrpid"); 241 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) || 242 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 243 seq_printf(seq, ",resuid=%u", 244 from_kuid_munged(&init_user_ns, sbi->s_resuid)); 245 } 246 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) || 247 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 248 seq_printf(seq, ",resgid=%u", 249 from_kgid_munged(&init_user_ns, sbi->s_resgid)); 250 } 251 if (test_opt(sb, ERRORS_RO)) { 252 int def_errors = le16_to_cpu(es->s_errors); 253 254 if (def_errors == EXT2_ERRORS_PANIC || 255 def_errors == EXT2_ERRORS_CONTINUE) { 256 seq_puts(seq, ",errors=remount-ro"); 257 } 258 } 259 if (test_opt(sb, ERRORS_CONT)) 260 seq_puts(seq, ",errors=continue"); 261 if (test_opt(sb, ERRORS_PANIC)) 262 seq_puts(seq, ",errors=panic"); 263 if (test_opt(sb, NO_UID32)) 264 seq_puts(seq, ",nouid32"); 265 if (test_opt(sb, DEBUG)) 266 seq_puts(seq, ",debug"); 267 if (test_opt(sb, OLDALLOC)) 268 seq_puts(seq, ",oldalloc"); 269 270 #ifdef CONFIG_EXT2_FS_XATTR 271 if (test_opt(sb, XATTR_USER)) 272 seq_puts(seq, ",user_xattr"); 273 if (!test_opt(sb, XATTR_USER) && 274 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 275 seq_puts(seq, ",nouser_xattr"); 276 } 277 #endif 278 279 #ifdef CONFIG_EXT2_FS_POSIX_ACL 280 if (test_opt(sb, POSIX_ACL)) 281 seq_puts(seq, ",acl"); 282 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 283 seq_puts(seq, ",noacl"); 284 #endif 285 286 if (test_opt(sb, NOBH)) 287 seq_puts(seq, ",nobh"); 288 289 #if defined(CONFIG_QUOTA) 290 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 291 seq_puts(seq, ",usrquota"); 292 293 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 294 seq_puts(seq, ",grpquota"); 295 #endif 296 297 #ifdef CONFIG_FS_DAX 298 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 299 seq_puts(seq, ",xip"); 300 if (sbi->s_mount_opt & EXT2_MOUNT_DAX) 301 seq_puts(seq, ",dax"); 302 #endif 303 304 if (!test_opt(sb, RESERVATION)) 305 seq_puts(seq, ",noreservation"); 306 307 spin_unlock(&sbi->s_lock); 308 return 0; 309 } 310 311 #ifdef CONFIG_QUOTA 312 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 313 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 314 static struct dquot **ext2_get_dquots(struct inode *inode) 315 { 316 return EXT2_I(inode)->i_dquot; 317 } 318 #endif 319 320 static const struct super_operations ext2_sops = { 321 .alloc_inode = ext2_alloc_inode, 322 .destroy_inode = ext2_destroy_inode, 323 .write_inode = ext2_write_inode, 324 .evict_inode = ext2_evict_inode, 325 .put_super = ext2_put_super, 326 .sync_fs = ext2_sync_fs, 327 .freeze_fs = ext2_freeze, 328 .unfreeze_fs = ext2_unfreeze, 329 .statfs = ext2_statfs, 330 .remount_fs = ext2_remount, 331 .show_options = ext2_show_options, 332 #ifdef CONFIG_QUOTA 333 .quota_read = ext2_quota_read, 334 .quota_write = ext2_quota_write, 335 .get_dquots = ext2_get_dquots, 336 #endif 337 }; 338 339 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 340 u64 ino, u32 generation) 341 { 342 struct inode *inode; 343 344 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 345 return ERR_PTR(-ESTALE); 346 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 347 return ERR_PTR(-ESTALE); 348 349 /* 350 * ext2_iget isn't quite right if the inode is currently unallocated! 351 * However ext2_iget currently does appropriate checks to handle stale 352 * inodes so everything is OK. 353 */ 354 inode = ext2_iget(sb, ino); 355 if (IS_ERR(inode)) 356 return ERR_CAST(inode); 357 if (generation && inode->i_generation != generation) { 358 /* we didn't find the right inode.. */ 359 iput(inode); 360 return ERR_PTR(-ESTALE); 361 } 362 return inode; 363 } 364 365 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 366 int fh_len, int fh_type) 367 { 368 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 369 ext2_nfs_get_inode); 370 } 371 372 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 373 int fh_len, int fh_type) 374 { 375 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 376 ext2_nfs_get_inode); 377 } 378 379 static const struct export_operations ext2_export_ops = { 380 .fh_to_dentry = ext2_fh_to_dentry, 381 .fh_to_parent = ext2_fh_to_parent, 382 .get_parent = ext2_get_parent, 383 }; 384 385 static unsigned long get_sb_block(void **data) 386 { 387 unsigned long sb_block; 388 char *options = (char *) *data; 389 390 if (!options || strncmp(options, "sb=", 3) != 0) 391 return 1; /* Default location */ 392 options += 3; 393 sb_block = simple_strtoul(options, &options, 0); 394 if (*options && *options != ',') { 395 printk("EXT2-fs: Invalid sb specification: %s\n", 396 (char *) *data); 397 return 1; 398 } 399 if (*options == ',') 400 options++; 401 *data = (void *) options; 402 return sb_block; 403 } 404 405 enum { 406 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 407 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 408 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 409 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 410 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota, 411 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 412 }; 413 414 static const match_table_t tokens = { 415 {Opt_bsd_df, "bsddf"}, 416 {Opt_minix_df, "minixdf"}, 417 {Opt_grpid, "grpid"}, 418 {Opt_grpid, "bsdgroups"}, 419 {Opt_nogrpid, "nogrpid"}, 420 {Opt_nogrpid, "sysvgroups"}, 421 {Opt_resgid, "resgid=%u"}, 422 {Opt_resuid, "resuid=%u"}, 423 {Opt_sb, "sb=%u"}, 424 {Opt_err_cont, "errors=continue"}, 425 {Opt_err_panic, "errors=panic"}, 426 {Opt_err_ro, "errors=remount-ro"}, 427 {Opt_nouid32, "nouid32"}, 428 {Opt_nocheck, "check=none"}, 429 {Opt_nocheck, "nocheck"}, 430 {Opt_debug, "debug"}, 431 {Opt_oldalloc, "oldalloc"}, 432 {Opt_orlov, "orlov"}, 433 {Opt_nobh, "nobh"}, 434 {Opt_user_xattr, "user_xattr"}, 435 {Opt_nouser_xattr, "nouser_xattr"}, 436 {Opt_acl, "acl"}, 437 {Opt_noacl, "noacl"}, 438 {Opt_xip, "xip"}, 439 {Opt_dax, "dax"}, 440 {Opt_grpquota, "grpquota"}, 441 {Opt_ignore, "noquota"}, 442 {Opt_quota, "quota"}, 443 {Opt_usrquota, "usrquota"}, 444 {Opt_reservation, "reservation"}, 445 {Opt_noreservation, "noreservation"}, 446 {Opt_err, NULL} 447 }; 448 449 static int parse_options(char *options, struct super_block *sb) 450 { 451 char *p; 452 struct ext2_sb_info *sbi = EXT2_SB(sb); 453 substring_t args[MAX_OPT_ARGS]; 454 int option; 455 kuid_t uid; 456 kgid_t gid; 457 458 if (!options) 459 return 1; 460 461 while ((p = strsep (&options, ",")) != NULL) { 462 int token; 463 if (!*p) 464 continue; 465 466 token = match_token(p, tokens, args); 467 switch (token) { 468 case Opt_bsd_df: 469 clear_opt (sbi->s_mount_opt, MINIX_DF); 470 break; 471 case Opt_minix_df: 472 set_opt (sbi->s_mount_opt, MINIX_DF); 473 break; 474 case Opt_grpid: 475 set_opt (sbi->s_mount_opt, GRPID); 476 break; 477 case Opt_nogrpid: 478 clear_opt (sbi->s_mount_opt, GRPID); 479 break; 480 case Opt_resuid: 481 if (match_int(&args[0], &option)) 482 return 0; 483 uid = make_kuid(current_user_ns(), option); 484 if (!uid_valid(uid)) { 485 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option); 486 return 0; 487 488 } 489 sbi->s_resuid = uid; 490 break; 491 case Opt_resgid: 492 if (match_int(&args[0], &option)) 493 return 0; 494 gid = make_kgid(current_user_ns(), option); 495 if (!gid_valid(gid)) { 496 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option); 497 return 0; 498 } 499 sbi->s_resgid = gid; 500 break; 501 case Opt_sb: 502 /* handled by get_sb_block() instead of here */ 503 /* *sb_block = match_int(&args[0]); */ 504 break; 505 case Opt_err_panic: 506 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 507 clear_opt (sbi->s_mount_opt, ERRORS_RO); 508 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 509 break; 510 case Opt_err_ro: 511 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 512 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 513 set_opt (sbi->s_mount_opt, ERRORS_RO); 514 break; 515 case Opt_err_cont: 516 clear_opt (sbi->s_mount_opt, ERRORS_RO); 517 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 518 set_opt (sbi->s_mount_opt, ERRORS_CONT); 519 break; 520 case Opt_nouid32: 521 set_opt (sbi->s_mount_opt, NO_UID32); 522 break; 523 case Opt_nocheck: 524 clear_opt (sbi->s_mount_opt, CHECK); 525 break; 526 case Opt_debug: 527 set_opt (sbi->s_mount_opt, DEBUG); 528 break; 529 case Opt_oldalloc: 530 set_opt (sbi->s_mount_opt, OLDALLOC); 531 break; 532 case Opt_orlov: 533 clear_opt (sbi->s_mount_opt, OLDALLOC); 534 break; 535 case Opt_nobh: 536 set_opt (sbi->s_mount_opt, NOBH); 537 break; 538 #ifdef CONFIG_EXT2_FS_XATTR 539 case Opt_user_xattr: 540 set_opt (sbi->s_mount_opt, XATTR_USER); 541 break; 542 case Opt_nouser_xattr: 543 clear_opt (sbi->s_mount_opt, XATTR_USER); 544 break; 545 #else 546 case Opt_user_xattr: 547 case Opt_nouser_xattr: 548 ext2_msg(sb, KERN_INFO, "(no)user_xattr options" 549 "not supported"); 550 break; 551 #endif 552 #ifdef CONFIG_EXT2_FS_POSIX_ACL 553 case Opt_acl: 554 set_opt(sbi->s_mount_opt, POSIX_ACL); 555 break; 556 case Opt_noacl: 557 clear_opt(sbi->s_mount_opt, POSIX_ACL); 558 break; 559 #else 560 case Opt_acl: 561 case Opt_noacl: 562 ext2_msg(sb, KERN_INFO, 563 "(no)acl options not supported"); 564 break; 565 #endif 566 case Opt_xip: 567 ext2_msg(sb, KERN_INFO, "use dax instead of xip"); 568 set_opt(sbi->s_mount_opt, XIP); 569 /* Fall through */ 570 case Opt_dax: 571 #ifdef CONFIG_FS_DAX 572 ext2_msg(sb, KERN_WARNING, 573 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk"); 574 set_opt(sbi->s_mount_opt, DAX); 575 #else 576 ext2_msg(sb, KERN_INFO, "dax option not supported"); 577 #endif 578 break; 579 580 #if defined(CONFIG_QUOTA) 581 case Opt_quota: 582 case Opt_usrquota: 583 set_opt(sbi->s_mount_opt, USRQUOTA); 584 break; 585 586 case Opt_grpquota: 587 set_opt(sbi->s_mount_opt, GRPQUOTA); 588 break; 589 #else 590 case Opt_quota: 591 case Opt_usrquota: 592 case Opt_grpquota: 593 ext2_msg(sb, KERN_INFO, 594 "quota operations not supported"); 595 break; 596 #endif 597 598 case Opt_reservation: 599 set_opt(sbi->s_mount_opt, RESERVATION); 600 ext2_msg(sb, KERN_INFO, "reservations ON"); 601 break; 602 case Opt_noreservation: 603 clear_opt(sbi->s_mount_opt, RESERVATION); 604 ext2_msg(sb, KERN_INFO, "reservations OFF"); 605 break; 606 case Opt_ignore: 607 break; 608 default: 609 return 0; 610 } 611 } 612 return 1; 613 } 614 615 static int ext2_setup_super (struct super_block * sb, 616 struct ext2_super_block * es, 617 int read_only) 618 { 619 int res = 0; 620 struct ext2_sb_info *sbi = EXT2_SB(sb); 621 622 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 623 ext2_msg(sb, KERN_ERR, 624 "error: revision level too high, " 625 "forcing read-only mode"); 626 res = MS_RDONLY; 627 } 628 if (read_only) 629 return res; 630 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 631 ext2_msg(sb, KERN_WARNING, 632 "warning: mounting unchecked fs, " 633 "running e2fsck is recommended"); 634 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 635 ext2_msg(sb, KERN_WARNING, 636 "warning: mounting fs with errors, " 637 "running e2fsck is recommended"); 638 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 639 le16_to_cpu(es->s_mnt_count) >= 640 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 641 ext2_msg(sb, KERN_WARNING, 642 "warning: maximal mount count reached, " 643 "running e2fsck is recommended"); 644 else if (le32_to_cpu(es->s_checkinterval) && 645 (le32_to_cpu(es->s_lastcheck) + 646 le32_to_cpu(es->s_checkinterval) <= get_seconds())) 647 ext2_msg(sb, KERN_WARNING, 648 "warning: checktime reached, " 649 "running e2fsck is recommended"); 650 if (!le16_to_cpu(es->s_max_mnt_count)) 651 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 652 le16_add_cpu(&es->s_mnt_count, 1); 653 if (test_opt (sb, DEBUG)) 654 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, " 655 "bpg=%lu, ipg=%lu, mo=%04lx]", 656 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 657 sbi->s_frag_size, 658 sbi->s_groups_count, 659 EXT2_BLOCKS_PER_GROUP(sb), 660 EXT2_INODES_PER_GROUP(sb), 661 sbi->s_mount_opt); 662 return res; 663 } 664 665 static int ext2_check_descriptors(struct super_block *sb) 666 { 667 int i; 668 struct ext2_sb_info *sbi = EXT2_SB(sb); 669 670 ext2_debug ("Checking group descriptors"); 671 672 for (i = 0; i < sbi->s_groups_count; i++) { 673 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 674 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 675 ext2_fsblk_t last_block; 676 677 if (i == sbi->s_groups_count - 1) 678 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 679 else 680 last_block = first_block + 681 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 682 683 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 684 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 685 { 686 ext2_error (sb, "ext2_check_descriptors", 687 "Block bitmap for group %d" 688 " not in group (block %lu)!", 689 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 690 return 0; 691 } 692 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 693 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 694 { 695 ext2_error (sb, "ext2_check_descriptors", 696 "Inode bitmap for group %d" 697 " not in group (block %lu)!", 698 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 699 return 0; 700 } 701 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 702 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 703 last_block) 704 { 705 ext2_error (sb, "ext2_check_descriptors", 706 "Inode table for group %d" 707 " not in group (block %lu)!", 708 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 709 return 0; 710 } 711 } 712 return 1; 713 } 714 715 /* 716 * Maximal file size. There is a direct, and {,double-,triple-}indirect 717 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 718 * We need to be 1 filesystem block less than the 2^32 sector limit. 719 */ 720 static loff_t ext2_max_size(int bits) 721 { 722 loff_t res = EXT2_NDIR_BLOCKS; 723 int meta_blocks; 724 loff_t upper_limit; 725 726 /* This is calculated to be the largest file size for a 727 * dense, file such that the total number of 728 * sectors in the file, including data and all indirect blocks, 729 * does not exceed 2^32 -1 730 * __u32 i_blocks representing the total number of 731 * 512 bytes blocks of the file 732 */ 733 upper_limit = (1LL << 32) - 1; 734 735 /* total blocks in file system block size */ 736 upper_limit >>= (bits - 9); 737 738 739 /* indirect blocks */ 740 meta_blocks = 1; 741 /* double indirect blocks */ 742 meta_blocks += 1 + (1LL << (bits-2)); 743 /* tripple indirect blocks */ 744 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2))); 745 746 upper_limit -= meta_blocks; 747 upper_limit <<= bits; 748 749 res += 1LL << (bits-2); 750 res += 1LL << (2*(bits-2)); 751 res += 1LL << (3*(bits-2)); 752 res <<= bits; 753 if (res > upper_limit) 754 res = upper_limit; 755 756 if (res > MAX_LFS_FILESIZE) 757 res = MAX_LFS_FILESIZE; 758 759 return res; 760 } 761 762 static unsigned long descriptor_loc(struct super_block *sb, 763 unsigned long logic_sb_block, 764 int nr) 765 { 766 struct ext2_sb_info *sbi = EXT2_SB(sb); 767 unsigned long bg, first_meta_bg; 768 int has_super = 0; 769 770 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 771 772 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 773 nr < first_meta_bg) 774 return (logic_sb_block + nr + 1); 775 bg = sbi->s_desc_per_block * nr; 776 if (ext2_bg_has_super(sb, bg)) 777 has_super = 1; 778 779 return ext2_group_first_block_no(sb, bg) + has_super; 780 } 781 782 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 783 { 784 struct buffer_head * bh; 785 struct ext2_sb_info * sbi; 786 struct ext2_super_block * es; 787 struct inode *root; 788 unsigned long block; 789 unsigned long sb_block = get_sb_block(&data); 790 unsigned long logic_sb_block; 791 unsigned long offset = 0; 792 unsigned long def_mount_opts; 793 long ret = -EINVAL; 794 int blocksize = BLOCK_SIZE; 795 int db_count; 796 int i, j; 797 __le32 features; 798 int err; 799 800 err = -ENOMEM; 801 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 802 if (!sbi) 803 goto failed; 804 805 sbi->s_blockgroup_lock = 806 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 807 if (!sbi->s_blockgroup_lock) { 808 kfree(sbi); 809 goto failed; 810 } 811 sb->s_fs_info = sbi; 812 sbi->s_sb_block = sb_block; 813 814 spin_lock_init(&sbi->s_lock); 815 816 /* 817 * See what the current blocksize for the device is, and 818 * use that as the blocksize. Otherwise (or if the blocksize 819 * is smaller than the default) use the default. 820 * This is important for devices that have a hardware 821 * sectorsize that is larger than the default. 822 */ 823 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 824 if (!blocksize) { 825 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 826 goto failed_sbi; 827 } 828 829 /* 830 * If the superblock doesn't start on a hardware sector boundary, 831 * calculate the offset. 832 */ 833 if (blocksize != BLOCK_SIZE) { 834 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 835 offset = (sb_block*BLOCK_SIZE) % blocksize; 836 } else { 837 logic_sb_block = sb_block; 838 } 839 840 if (!(bh = sb_bread(sb, logic_sb_block))) { 841 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 842 goto failed_sbi; 843 } 844 /* 845 * Note: s_es must be initialized as soon as possible because 846 * some ext2 macro-instructions depend on its value 847 */ 848 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 849 sbi->s_es = es; 850 sb->s_magic = le16_to_cpu(es->s_magic); 851 852 if (sb->s_magic != EXT2_SUPER_MAGIC) 853 goto cantfind_ext2; 854 855 /* Set defaults before we parse the mount options */ 856 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 857 if (def_mount_opts & EXT2_DEFM_DEBUG) 858 set_opt(sbi->s_mount_opt, DEBUG); 859 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 860 set_opt(sbi->s_mount_opt, GRPID); 861 if (def_mount_opts & EXT2_DEFM_UID16) 862 set_opt(sbi->s_mount_opt, NO_UID32); 863 #ifdef CONFIG_EXT2_FS_XATTR 864 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 865 set_opt(sbi->s_mount_opt, XATTR_USER); 866 #endif 867 #ifdef CONFIG_EXT2_FS_POSIX_ACL 868 if (def_mount_opts & EXT2_DEFM_ACL) 869 set_opt(sbi->s_mount_opt, POSIX_ACL); 870 #endif 871 872 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 873 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 874 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 875 set_opt(sbi->s_mount_opt, ERRORS_CONT); 876 else 877 set_opt(sbi->s_mount_opt, ERRORS_RO); 878 879 sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid)); 880 sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid)); 881 882 set_opt(sbi->s_mount_opt, RESERVATION); 883 884 if (!parse_options((char *) data, sb)) 885 goto failed_mount; 886 887 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 888 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 889 MS_POSIXACL : 0); 890 sb->s_iflags |= SB_I_CGROUPWB; 891 892 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 893 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 894 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 895 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 896 ext2_msg(sb, KERN_WARNING, 897 "warning: feature flags set on rev 0 fs, " 898 "running e2fsck is recommended"); 899 /* 900 * Check feature flags regardless of the revision level, since we 901 * previously didn't change the revision level when setting the flags, 902 * so there is a chance incompat flags are set on a rev 0 filesystem. 903 */ 904 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 905 if (features) { 906 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 907 "unsupported optional features (%x)", 908 le32_to_cpu(features)); 909 goto failed_mount; 910 } 911 if (!(sb->s_flags & MS_RDONLY) && 912 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 913 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 914 "unsupported optional features (%x)", 915 le32_to_cpu(features)); 916 goto failed_mount; 917 } 918 919 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 920 921 if (sbi->s_mount_opt & EXT2_MOUNT_DAX) { 922 if (blocksize != PAGE_SIZE) { 923 ext2_msg(sb, KERN_ERR, 924 "error: unsupported blocksize for dax"); 925 goto failed_mount; 926 } 927 if (!sb->s_bdev->bd_disk->fops->direct_access) { 928 ext2_msg(sb, KERN_ERR, 929 "error: device does not support dax"); 930 goto failed_mount; 931 } 932 } 933 934 /* If the blocksize doesn't match, re-read the thing.. */ 935 if (sb->s_blocksize != blocksize) { 936 brelse(bh); 937 938 if (!sb_set_blocksize(sb, blocksize)) { 939 ext2_msg(sb, KERN_ERR, 940 "error: bad blocksize %d", blocksize); 941 goto failed_sbi; 942 } 943 944 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 945 offset = (sb_block*BLOCK_SIZE) % blocksize; 946 bh = sb_bread(sb, logic_sb_block); 947 if(!bh) { 948 ext2_msg(sb, KERN_ERR, "error: couldn't read" 949 "superblock on 2nd try"); 950 goto failed_sbi; 951 } 952 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 953 sbi->s_es = es; 954 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 955 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 956 goto failed_mount; 957 } 958 } 959 960 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 961 sb->s_max_links = EXT2_LINK_MAX; 962 963 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 964 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 965 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 966 } else { 967 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 968 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 969 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 970 !is_power_of_2(sbi->s_inode_size) || 971 (sbi->s_inode_size > blocksize)) { 972 ext2_msg(sb, KERN_ERR, 973 "error: unsupported inode size: %d", 974 sbi->s_inode_size); 975 goto failed_mount; 976 } 977 } 978 979 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 980 le32_to_cpu(es->s_log_frag_size); 981 if (sbi->s_frag_size == 0) 982 goto cantfind_ext2; 983 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 984 985 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 986 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 987 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 988 989 if (EXT2_INODE_SIZE(sb) == 0) 990 goto cantfind_ext2; 991 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 992 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 993 goto cantfind_ext2; 994 sbi->s_itb_per_group = sbi->s_inodes_per_group / 995 sbi->s_inodes_per_block; 996 sbi->s_desc_per_block = sb->s_blocksize / 997 sizeof (struct ext2_group_desc); 998 sbi->s_sbh = bh; 999 sbi->s_mount_state = le16_to_cpu(es->s_state); 1000 sbi->s_addr_per_block_bits = 1001 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 1002 sbi->s_desc_per_block_bits = 1003 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 1004 1005 if (sb->s_magic != EXT2_SUPER_MAGIC) 1006 goto cantfind_ext2; 1007 1008 if (sb->s_blocksize != bh->b_size) { 1009 if (!silent) 1010 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 1011 goto failed_mount; 1012 } 1013 1014 if (sb->s_blocksize != sbi->s_frag_size) { 1015 ext2_msg(sb, KERN_ERR, 1016 "error: fragsize %lu != blocksize %lu" 1017 "(not supported yet)", 1018 sbi->s_frag_size, sb->s_blocksize); 1019 goto failed_mount; 1020 } 1021 1022 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 1023 ext2_msg(sb, KERN_ERR, 1024 "error: #blocks per group too big: %lu", 1025 sbi->s_blocks_per_group); 1026 goto failed_mount; 1027 } 1028 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 1029 ext2_msg(sb, KERN_ERR, 1030 "error: #fragments per group too big: %lu", 1031 sbi->s_frags_per_group); 1032 goto failed_mount; 1033 } 1034 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 1035 ext2_msg(sb, KERN_ERR, 1036 "error: #inodes per group too big: %lu", 1037 sbi->s_inodes_per_group); 1038 goto failed_mount; 1039 } 1040 1041 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 1042 goto cantfind_ext2; 1043 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1044 le32_to_cpu(es->s_first_data_block) - 1) 1045 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1046 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1047 EXT2_DESC_PER_BLOCK(sb); 1048 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 1049 if (sbi->s_group_desc == NULL) { 1050 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1051 goto failed_mount; 1052 } 1053 bgl_lock_init(sbi->s_blockgroup_lock); 1054 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1055 if (!sbi->s_debts) { 1056 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1057 goto failed_mount_group_desc; 1058 } 1059 for (i = 0; i < db_count; i++) { 1060 block = descriptor_loc(sb, logic_sb_block, i); 1061 sbi->s_group_desc[i] = sb_bread(sb, block); 1062 if (!sbi->s_group_desc[i]) { 1063 for (j = 0; j < i; j++) 1064 brelse (sbi->s_group_desc[j]); 1065 ext2_msg(sb, KERN_ERR, 1066 "error: unable to read group descriptors"); 1067 goto failed_mount_group_desc; 1068 } 1069 } 1070 if (!ext2_check_descriptors (sb)) { 1071 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1072 goto failed_mount2; 1073 } 1074 sbi->s_gdb_count = db_count; 1075 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1076 spin_lock_init(&sbi->s_next_gen_lock); 1077 1078 /* per fileystem reservation list head & lock */ 1079 spin_lock_init(&sbi->s_rsv_window_lock); 1080 sbi->s_rsv_window_root = RB_ROOT; 1081 /* 1082 * Add a single, static dummy reservation to the start of the 1083 * reservation window list --- it gives us a placeholder for 1084 * append-at-start-of-list which makes the allocation logic 1085 * _much_ simpler. 1086 */ 1087 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1088 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1089 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1090 sbi->s_rsv_window_head.rsv_goal_size = 0; 1091 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1092 1093 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1094 ext2_count_free_blocks(sb), GFP_KERNEL); 1095 if (!err) { 1096 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1097 ext2_count_free_inodes(sb), GFP_KERNEL); 1098 } 1099 if (!err) { 1100 err = percpu_counter_init(&sbi->s_dirs_counter, 1101 ext2_count_dirs(sb), GFP_KERNEL); 1102 } 1103 if (err) { 1104 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1105 goto failed_mount3; 1106 } 1107 /* 1108 * set up enough so that it can read an inode 1109 */ 1110 sb->s_op = &ext2_sops; 1111 sb->s_export_op = &ext2_export_ops; 1112 sb->s_xattr = ext2_xattr_handlers; 1113 1114 #ifdef CONFIG_QUOTA 1115 sb->dq_op = &dquot_operations; 1116 sb->s_qcop = &dquot_quotactl_ops; 1117 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP; 1118 #endif 1119 1120 root = ext2_iget(sb, EXT2_ROOT_INO); 1121 if (IS_ERR(root)) { 1122 ret = PTR_ERR(root); 1123 goto failed_mount3; 1124 } 1125 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1126 iput(root); 1127 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1128 goto failed_mount3; 1129 } 1130 1131 sb->s_root = d_make_root(root); 1132 if (!sb->s_root) { 1133 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1134 ret = -ENOMEM; 1135 goto failed_mount3; 1136 } 1137 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1138 ext2_msg(sb, KERN_WARNING, 1139 "warning: mounting ext3 filesystem as ext2"); 1140 if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY)) 1141 sb->s_flags |= MS_RDONLY; 1142 ext2_write_super(sb); 1143 return 0; 1144 1145 cantfind_ext2: 1146 if (!silent) 1147 ext2_msg(sb, KERN_ERR, 1148 "error: can't find an ext2 filesystem on dev %s.", 1149 sb->s_id); 1150 goto failed_mount; 1151 failed_mount3: 1152 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1153 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1154 percpu_counter_destroy(&sbi->s_dirs_counter); 1155 failed_mount2: 1156 for (i = 0; i < db_count; i++) 1157 brelse(sbi->s_group_desc[i]); 1158 failed_mount_group_desc: 1159 kfree(sbi->s_group_desc); 1160 kfree(sbi->s_debts); 1161 failed_mount: 1162 brelse(bh); 1163 failed_sbi: 1164 sb->s_fs_info = NULL; 1165 kfree(sbi->s_blockgroup_lock); 1166 kfree(sbi); 1167 failed: 1168 return ret; 1169 } 1170 1171 static void ext2_clear_super_error(struct super_block *sb) 1172 { 1173 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1174 1175 if (buffer_write_io_error(sbh)) { 1176 /* 1177 * Oh, dear. A previous attempt to write the 1178 * superblock failed. This could happen because the 1179 * USB device was yanked out. Or it could happen to 1180 * be a transient write error and maybe the block will 1181 * be remapped. Nothing we can do but to retry the 1182 * write and hope for the best. 1183 */ 1184 ext2_msg(sb, KERN_ERR, 1185 "previous I/O error to superblock detected\n"); 1186 clear_buffer_write_io_error(sbh); 1187 set_buffer_uptodate(sbh); 1188 } 1189 } 1190 1191 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, 1192 int wait) 1193 { 1194 ext2_clear_super_error(sb); 1195 spin_lock(&EXT2_SB(sb)->s_lock); 1196 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1197 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1198 es->s_wtime = cpu_to_le32(get_seconds()); 1199 /* unlock before we do IO */ 1200 spin_unlock(&EXT2_SB(sb)->s_lock); 1201 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1202 if (wait) 1203 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1204 } 1205 1206 /* 1207 * In the second extended file system, it is not necessary to 1208 * write the super block since we use a mapping of the 1209 * disk super block in a buffer. 1210 * 1211 * However, this function is still used to set the fs valid 1212 * flags to 0. We need to set this flag to 0 since the fs 1213 * may have been checked while mounted and e2fsck may have 1214 * set s_state to EXT2_VALID_FS after some corrections. 1215 */ 1216 static int ext2_sync_fs(struct super_block *sb, int wait) 1217 { 1218 struct ext2_sb_info *sbi = EXT2_SB(sb); 1219 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1220 1221 /* 1222 * Write quota structures to quota file, sync_blockdev() will write 1223 * them to disk later 1224 */ 1225 dquot_writeback_dquots(sb, -1); 1226 1227 spin_lock(&sbi->s_lock); 1228 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1229 ext2_debug("setting valid to 0\n"); 1230 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1231 } 1232 spin_unlock(&sbi->s_lock); 1233 ext2_sync_super(sb, es, wait); 1234 return 0; 1235 } 1236 1237 static int ext2_freeze(struct super_block *sb) 1238 { 1239 struct ext2_sb_info *sbi = EXT2_SB(sb); 1240 1241 /* 1242 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared 1243 * because we have unattached inodes and thus filesystem is not fully 1244 * consistent. 1245 */ 1246 if (atomic_long_read(&sb->s_remove_count)) { 1247 ext2_sync_fs(sb, 1); 1248 return 0; 1249 } 1250 /* Set EXT2_FS_VALID flag */ 1251 spin_lock(&sbi->s_lock); 1252 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); 1253 spin_unlock(&sbi->s_lock); 1254 ext2_sync_super(sb, sbi->s_es, 1); 1255 1256 return 0; 1257 } 1258 1259 static int ext2_unfreeze(struct super_block *sb) 1260 { 1261 /* Just write sb to clear EXT2_VALID_FS flag */ 1262 ext2_write_super(sb); 1263 1264 return 0; 1265 } 1266 1267 void ext2_write_super(struct super_block *sb) 1268 { 1269 if (!(sb->s_flags & MS_RDONLY)) 1270 ext2_sync_fs(sb, 1); 1271 } 1272 1273 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1274 { 1275 struct ext2_sb_info * sbi = EXT2_SB(sb); 1276 struct ext2_super_block * es; 1277 struct ext2_mount_options old_opts; 1278 unsigned long old_sb_flags; 1279 int err; 1280 1281 sync_filesystem(sb); 1282 spin_lock(&sbi->s_lock); 1283 1284 /* Store the old options */ 1285 old_sb_flags = sb->s_flags; 1286 old_opts.s_mount_opt = sbi->s_mount_opt; 1287 old_opts.s_resuid = sbi->s_resuid; 1288 old_opts.s_resgid = sbi->s_resgid; 1289 1290 /* 1291 * Allow the "check" option to be passed as a remount option. 1292 */ 1293 if (!parse_options(data, sb)) { 1294 err = -EINVAL; 1295 goto restore_opts; 1296 } 1297 1298 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1299 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1300 1301 es = sbi->s_es; 1302 if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT2_MOUNT_DAX) { 1303 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1304 "dax flag with busy inodes while remounting"); 1305 sbi->s_mount_opt ^= EXT2_MOUNT_DAX; 1306 } 1307 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { 1308 spin_unlock(&sbi->s_lock); 1309 return 0; 1310 } 1311 if (*flags & MS_RDONLY) { 1312 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1313 !(sbi->s_mount_state & EXT2_VALID_FS)) { 1314 spin_unlock(&sbi->s_lock); 1315 return 0; 1316 } 1317 1318 /* 1319 * OK, we are remounting a valid rw partition rdonly, so set 1320 * the rdonly flag and then mark the partition as valid again. 1321 */ 1322 es->s_state = cpu_to_le16(sbi->s_mount_state); 1323 es->s_mtime = cpu_to_le32(get_seconds()); 1324 spin_unlock(&sbi->s_lock); 1325 1326 err = dquot_suspend(sb, -1); 1327 if (err < 0) { 1328 spin_lock(&sbi->s_lock); 1329 goto restore_opts; 1330 } 1331 1332 ext2_sync_super(sb, es, 1); 1333 } else { 1334 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1335 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1336 if (ret) { 1337 ext2_msg(sb, KERN_WARNING, 1338 "warning: couldn't remount RDWR because of " 1339 "unsupported optional features (%x).", 1340 le32_to_cpu(ret)); 1341 err = -EROFS; 1342 goto restore_opts; 1343 } 1344 /* 1345 * Mounting a RDONLY partition read-write, so reread and 1346 * store the current valid flag. (It may have been changed 1347 * by e2fsck since we originally mounted the partition.) 1348 */ 1349 sbi->s_mount_state = le16_to_cpu(es->s_state); 1350 if (!ext2_setup_super (sb, es, 0)) 1351 sb->s_flags &= ~MS_RDONLY; 1352 spin_unlock(&sbi->s_lock); 1353 1354 ext2_write_super(sb); 1355 1356 dquot_resume(sb, -1); 1357 } 1358 1359 return 0; 1360 restore_opts: 1361 sbi->s_mount_opt = old_opts.s_mount_opt; 1362 sbi->s_resuid = old_opts.s_resuid; 1363 sbi->s_resgid = old_opts.s_resgid; 1364 sb->s_flags = old_sb_flags; 1365 spin_unlock(&sbi->s_lock); 1366 return err; 1367 } 1368 1369 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1370 { 1371 struct super_block *sb = dentry->d_sb; 1372 struct ext2_sb_info *sbi = EXT2_SB(sb); 1373 struct ext2_super_block *es = sbi->s_es; 1374 u64 fsid; 1375 1376 spin_lock(&sbi->s_lock); 1377 1378 if (test_opt (sb, MINIX_DF)) 1379 sbi->s_overhead_last = 0; 1380 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1381 unsigned long i, overhead = 0; 1382 smp_rmb(); 1383 1384 /* 1385 * Compute the overhead (FS structures). This is constant 1386 * for a given filesystem unless the number of block groups 1387 * changes so we cache the previous value until it does. 1388 */ 1389 1390 /* 1391 * All of the blocks before first_data_block are 1392 * overhead 1393 */ 1394 overhead = le32_to_cpu(es->s_first_data_block); 1395 1396 /* 1397 * Add the overhead attributed to the superblock and 1398 * block group descriptors. If the sparse superblocks 1399 * feature is turned on, then not all groups have this. 1400 */ 1401 for (i = 0; i < sbi->s_groups_count; i++) 1402 overhead += ext2_bg_has_super(sb, i) + 1403 ext2_bg_num_gdb(sb, i); 1404 1405 /* 1406 * Every block group has an inode bitmap, a block 1407 * bitmap, and an inode table. 1408 */ 1409 overhead += (sbi->s_groups_count * 1410 (2 + sbi->s_itb_per_group)); 1411 sbi->s_overhead_last = overhead; 1412 smp_wmb(); 1413 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1414 } 1415 1416 buf->f_type = EXT2_SUPER_MAGIC; 1417 buf->f_bsize = sb->s_blocksize; 1418 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1419 buf->f_bfree = ext2_count_free_blocks(sb); 1420 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1421 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1422 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1423 buf->f_bavail = 0; 1424 buf->f_files = le32_to_cpu(es->s_inodes_count); 1425 buf->f_ffree = ext2_count_free_inodes(sb); 1426 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1427 buf->f_namelen = EXT2_NAME_LEN; 1428 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1429 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1430 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1431 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1432 spin_unlock(&sbi->s_lock); 1433 return 0; 1434 } 1435 1436 static struct dentry *ext2_mount(struct file_system_type *fs_type, 1437 int flags, const char *dev_name, void *data) 1438 { 1439 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1440 } 1441 1442 #ifdef CONFIG_QUOTA 1443 1444 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1445 * acquiring the locks... As quota files are never truncated and quota code 1446 * itself serializes the operations (and no one else should touch the files) 1447 * we don't have to be afraid of races */ 1448 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1449 size_t len, loff_t off) 1450 { 1451 struct inode *inode = sb_dqopt(sb)->files[type]; 1452 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1453 int err = 0; 1454 int offset = off & (sb->s_blocksize - 1); 1455 int tocopy; 1456 size_t toread; 1457 struct buffer_head tmp_bh; 1458 struct buffer_head *bh; 1459 loff_t i_size = i_size_read(inode); 1460 1461 if (off > i_size) 1462 return 0; 1463 if (off+len > i_size) 1464 len = i_size-off; 1465 toread = len; 1466 while (toread > 0) { 1467 tocopy = sb->s_blocksize - offset < toread ? 1468 sb->s_blocksize - offset : toread; 1469 1470 tmp_bh.b_state = 0; 1471 tmp_bh.b_size = sb->s_blocksize; 1472 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1473 if (err < 0) 1474 return err; 1475 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1476 memset(data, 0, tocopy); 1477 else { 1478 bh = sb_bread(sb, tmp_bh.b_blocknr); 1479 if (!bh) 1480 return -EIO; 1481 memcpy(data, bh->b_data+offset, tocopy); 1482 brelse(bh); 1483 } 1484 offset = 0; 1485 toread -= tocopy; 1486 data += tocopy; 1487 blk++; 1488 } 1489 return len; 1490 } 1491 1492 /* Write to quotafile */ 1493 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1494 const char *data, size_t len, loff_t off) 1495 { 1496 struct inode *inode = sb_dqopt(sb)->files[type]; 1497 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1498 int err = 0; 1499 int offset = off & (sb->s_blocksize - 1); 1500 int tocopy; 1501 size_t towrite = len; 1502 struct buffer_head tmp_bh; 1503 struct buffer_head *bh; 1504 1505 while (towrite > 0) { 1506 tocopy = sb->s_blocksize - offset < towrite ? 1507 sb->s_blocksize - offset : towrite; 1508 1509 tmp_bh.b_state = 0; 1510 tmp_bh.b_size = sb->s_blocksize; 1511 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1512 if (err < 0) 1513 goto out; 1514 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1515 bh = sb_bread(sb, tmp_bh.b_blocknr); 1516 else 1517 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1518 if (unlikely(!bh)) { 1519 err = -EIO; 1520 goto out; 1521 } 1522 lock_buffer(bh); 1523 memcpy(bh->b_data+offset, data, tocopy); 1524 flush_dcache_page(bh->b_page); 1525 set_buffer_uptodate(bh); 1526 mark_buffer_dirty(bh); 1527 unlock_buffer(bh); 1528 brelse(bh); 1529 offset = 0; 1530 towrite -= tocopy; 1531 data += tocopy; 1532 blk++; 1533 } 1534 out: 1535 if (len == towrite) 1536 return err; 1537 if (inode->i_size < off+len-towrite) 1538 i_size_write(inode, off+len-towrite); 1539 inode->i_version++; 1540 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1541 mark_inode_dirty(inode); 1542 return len - towrite; 1543 } 1544 1545 #endif 1546 1547 static struct file_system_type ext2_fs_type = { 1548 .owner = THIS_MODULE, 1549 .name = "ext2", 1550 .mount = ext2_mount, 1551 .kill_sb = kill_block_super, 1552 .fs_flags = FS_REQUIRES_DEV, 1553 }; 1554 MODULE_ALIAS_FS("ext2"); 1555 1556 static int __init init_ext2_fs(void) 1557 { 1558 int err = init_ext2_xattr(); 1559 if (err) 1560 return err; 1561 err = init_inodecache(); 1562 if (err) 1563 goto out1; 1564 err = register_filesystem(&ext2_fs_type); 1565 if (err) 1566 goto out; 1567 return 0; 1568 out: 1569 destroy_inodecache(); 1570 out1: 1571 exit_ext2_xattr(); 1572 return err; 1573 } 1574 1575 static void __exit exit_ext2_fs(void) 1576 { 1577 unregister_filesystem(&ext2_fs_type); 1578 destroy_inodecache(); 1579 exit_ext2_xattr(); 1580 } 1581 1582 MODULE_AUTHOR("Remy Card and others"); 1583 MODULE_DESCRIPTION("Second Extended Filesystem"); 1584 MODULE_LICENSE("GPL"); 1585 module_init(init_ext2_fs) 1586 module_exit(exit_ext2_fs) 1587