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 if (sbi->s_mb_cache) { 135 ext2_xattr_destroy_cache(sbi->s_mb_cache); 136 sbi->s_mb_cache = NULL; 137 } 138 if (!(sb->s_flags & MS_RDONLY)) { 139 struct ext2_super_block *es = sbi->s_es; 140 141 spin_lock(&sbi->s_lock); 142 es->s_state = cpu_to_le16(sbi->s_mount_state); 143 spin_unlock(&sbi->s_lock); 144 ext2_sync_super(sb, es, 1); 145 } 146 db_count = sbi->s_gdb_count; 147 for (i = 0; i < db_count; i++) 148 if (sbi->s_group_desc[i]) 149 brelse (sbi->s_group_desc[i]); 150 kfree(sbi->s_group_desc); 151 kfree(sbi->s_debts); 152 percpu_counter_destroy(&sbi->s_freeblocks_counter); 153 percpu_counter_destroy(&sbi->s_freeinodes_counter); 154 percpu_counter_destroy(&sbi->s_dirs_counter); 155 brelse (sbi->s_sbh); 156 sb->s_fs_info = NULL; 157 kfree(sbi->s_blockgroup_lock); 158 kfree(sbi); 159 } 160 161 static struct kmem_cache * ext2_inode_cachep; 162 163 static struct inode *ext2_alloc_inode(struct super_block *sb) 164 { 165 struct ext2_inode_info *ei; 166 ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL); 167 if (!ei) 168 return NULL; 169 ei->i_block_alloc_info = NULL; 170 ei->vfs_inode.i_version = 1; 171 #ifdef CONFIG_QUOTA 172 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot)); 173 #endif 174 175 return &ei->vfs_inode; 176 } 177 178 static void ext2_i_callback(struct rcu_head *head) 179 { 180 struct inode *inode = container_of(head, struct inode, i_rcu); 181 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 182 } 183 184 static void ext2_destroy_inode(struct inode *inode) 185 { 186 call_rcu(&inode->i_rcu, ext2_i_callback); 187 } 188 189 static void init_once(void *foo) 190 { 191 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 192 193 rwlock_init(&ei->i_meta_lock); 194 #ifdef CONFIG_EXT2_FS_XATTR 195 init_rwsem(&ei->xattr_sem); 196 #endif 197 mutex_init(&ei->truncate_mutex); 198 #ifdef CONFIG_FS_DAX 199 init_rwsem(&ei->dax_sem); 200 #endif 201 inode_init_once(&ei->vfs_inode); 202 } 203 204 static int __init init_inodecache(void) 205 { 206 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 207 sizeof(struct ext2_inode_info), 208 0, (SLAB_RECLAIM_ACCOUNT| 209 SLAB_MEM_SPREAD|SLAB_ACCOUNT), 210 init_once); 211 if (ext2_inode_cachep == NULL) 212 return -ENOMEM; 213 return 0; 214 } 215 216 static void destroy_inodecache(void) 217 { 218 /* 219 * Make sure all delayed rcu free inodes are flushed before we 220 * destroy cache. 221 */ 222 rcu_barrier(); 223 kmem_cache_destroy(ext2_inode_cachep); 224 } 225 226 static int ext2_show_options(struct seq_file *seq, struct dentry *root) 227 { 228 struct super_block *sb = root->d_sb; 229 struct ext2_sb_info *sbi = EXT2_SB(sb); 230 struct ext2_super_block *es = sbi->s_es; 231 unsigned long def_mount_opts; 232 233 spin_lock(&sbi->s_lock); 234 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 235 236 if (sbi->s_sb_block != 1) 237 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 238 if (test_opt(sb, MINIX_DF)) 239 seq_puts(seq, ",minixdf"); 240 if (test_opt(sb, GRPID)) 241 seq_puts(seq, ",grpid"); 242 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 243 seq_puts(seq, ",nogrpid"); 244 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) || 245 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 246 seq_printf(seq, ",resuid=%u", 247 from_kuid_munged(&init_user_ns, sbi->s_resuid)); 248 } 249 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) || 250 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 251 seq_printf(seq, ",resgid=%u", 252 from_kgid_munged(&init_user_ns, sbi->s_resgid)); 253 } 254 if (test_opt(sb, ERRORS_RO)) { 255 int def_errors = le16_to_cpu(es->s_errors); 256 257 if (def_errors == EXT2_ERRORS_PANIC || 258 def_errors == EXT2_ERRORS_CONTINUE) { 259 seq_puts(seq, ",errors=remount-ro"); 260 } 261 } 262 if (test_opt(sb, ERRORS_CONT)) 263 seq_puts(seq, ",errors=continue"); 264 if (test_opt(sb, ERRORS_PANIC)) 265 seq_puts(seq, ",errors=panic"); 266 if (test_opt(sb, NO_UID32)) 267 seq_puts(seq, ",nouid32"); 268 if (test_opt(sb, DEBUG)) 269 seq_puts(seq, ",debug"); 270 if (test_opt(sb, OLDALLOC)) 271 seq_puts(seq, ",oldalloc"); 272 273 #ifdef CONFIG_EXT2_FS_XATTR 274 if (test_opt(sb, XATTR_USER)) 275 seq_puts(seq, ",user_xattr"); 276 if (!test_opt(sb, XATTR_USER) && 277 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 278 seq_puts(seq, ",nouser_xattr"); 279 } 280 #endif 281 282 #ifdef CONFIG_EXT2_FS_POSIX_ACL 283 if (test_opt(sb, POSIX_ACL)) 284 seq_puts(seq, ",acl"); 285 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 286 seq_puts(seq, ",noacl"); 287 #endif 288 289 if (test_opt(sb, NOBH)) 290 seq_puts(seq, ",nobh"); 291 292 #if defined(CONFIG_QUOTA) 293 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 294 seq_puts(seq, ",usrquota"); 295 296 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 297 seq_puts(seq, ",grpquota"); 298 #endif 299 300 #ifdef CONFIG_FS_DAX 301 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 302 seq_puts(seq, ",xip"); 303 if (sbi->s_mount_opt & EXT2_MOUNT_DAX) 304 seq_puts(seq, ",dax"); 305 #endif 306 307 if (!test_opt(sb, RESERVATION)) 308 seq_puts(seq, ",noreservation"); 309 310 spin_unlock(&sbi->s_lock); 311 return 0; 312 } 313 314 #ifdef CONFIG_QUOTA 315 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 316 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 317 static struct dquot **ext2_get_dquots(struct inode *inode) 318 { 319 return EXT2_I(inode)->i_dquot; 320 } 321 #endif 322 323 static const struct super_operations ext2_sops = { 324 .alloc_inode = ext2_alloc_inode, 325 .destroy_inode = ext2_destroy_inode, 326 .write_inode = ext2_write_inode, 327 .evict_inode = ext2_evict_inode, 328 .put_super = ext2_put_super, 329 .sync_fs = ext2_sync_fs, 330 .freeze_fs = ext2_freeze, 331 .unfreeze_fs = ext2_unfreeze, 332 .statfs = ext2_statfs, 333 .remount_fs = ext2_remount, 334 .show_options = ext2_show_options, 335 #ifdef CONFIG_QUOTA 336 .quota_read = ext2_quota_read, 337 .quota_write = ext2_quota_write, 338 .get_dquots = ext2_get_dquots, 339 #endif 340 }; 341 342 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 343 u64 ino, u32 generation) 344 { 345 struct inode *inode; 346 347 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 348 return ERR_PTR(-ESTALE); 349 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 350 return ERR_PTR(-ESTALE); 351 352 /* 353 * ext2_iget isn't quite right if the inode is currently unallocated! 354 * However ext2_iget currently does appropriate checks to handle stale 355 * inodes so everything is OK. 356 */ 357 inode = ext2_iget(sb, ino); 358 if (IS_ERR(inode)) 359 return ERR_CAST(inode); 360 if (generation && inode->i_generation != generation) { 361 /* we didn't find the right inode.. */ 362 iput(inode); 363 return ERR_PTR(-ESTALE); 364 } 365 return inode; 366 } 367 368 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 369 int fh_len, int fh_type) 370 { 371 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 372 ext2_nfs_get_inode); 373 } 374 375 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 376 int fh_len, int fh_type) 377 { 378 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 379 ext2_nfs_get_inode); 380 } 381 382 static const struct export_operations ext2_export_ops = { 383 .fh_to_dentry = ext2_fh_to_dentry, 384 .fh_to_parent = ext2_fh_to_parent, 385 .get_parent = ext2_get_parent, 386 }; 387 388 static unsigned long get_sb_block(void **data) 389 { 390 unsigned long sb_block; 391 char *options = (char *) *data; 392 393 if (!options || strncmp(options, "sb=", 3) != 0) 394 return 1; /* Default location */ 395 options += 3; 396 sb_block = simple_strtoul(options, &options, 0); 397 if (*options && *options != ',') { 398 printk("EXT2-fs: Invalid sb specification: %s\n", 399 (char *) *data); 400 return 1; 401 } 402 if (*options == ',') 403 options++; 404 *data = (void *) options; 405 return sb_block; 406 } 407 408 enum { 409 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 410 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 411 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 412 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 413 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota, 414 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 415 }; 416 417 static const match_table_t tokens = { 418 {Opt_bsd_df, "bsddf"}, 419 {Opt_minix_df, "minixdf"}, 420 {Opt_grpid, "grpid"}, 421 {Opt_grpid, "bsdgroups"}, 422 {Opt_nogrpid, "nogrpid"}, 423 {Opt_nogrpid, "sysvgroups"}, 424 {Opt_resgid, "resgid=%u"}, 425 {Opt_resuid, "resuid=%u"}, 426 {Opt_sb, "sb=%u"}, 427 {Opt_err_cont, "errors=continue"}, 428 {Opt_err_panic, "errors=panic"}, 429 {Opt_err_ro, "errors=remount-ro"}, 430 {Opt_nouid32, "nouid32"}, 431 {Opt_nocheck, "check=none"}, 432 {Opt_nocheck, "nocheck"}, 433 {Opt_debug, "debug"}, 434 {Opt_oldalloc, "oldalloc"}, 435 {Opt_orlov, "orlov"}, 436 {Opt_nobh, "nobh"}, 437 {Opt_user_xattr, "user_xattr"}, 438 {Opt_nouser_xattr, "nouser_xattr"}, 439 {Opt_acl, "acl"}, 440 {Opt_noacl, "noacl"}, 441 {Opt_xip, "xip"}, 442 {Opt_dax, "dax"}, 443 {Opt_grpquota, "grpquota"}, 444 {Opt_ignore, "noquota"}, 445 {Opt_quota, "quota"}, 446 {Opt_usrquota, "usrquota"}, 447 {Opt_reservation, "reservation"}, 448 {Opt_noreservation, "noreservation"}, 449 {Opt_err, NULL} 450 }; 451 452 static int parse_options(char *options, struct super_block *sb) 453 { 454 char *p; 455 struct ext2_sb_info *sbi = EXT2_SB(sb); 456 substring_t args[MAX_OPT_ARGS]; 457 int option; 458 kuid_t uid; 459 kgid_t gid; 460 461 if (!options) 462 return 1; 463 464 while ((p = strsep (&options, ",")) != NULL) { 465 int token; 466 if (!*p) 467 continue; 468 469 token = match_token(p, tokens, args); 470 switch (token) { 471 case Opt_bsd_df: 472 clear_opt (sbi->s_mount_opt, MINIX_DF); 473 break; 474 case Opt_minix_df: 475 set_opt (sbi->s_mount_opt, MINIX_DF); 476 break; 477 case Opt_grpid: 478 set_opt (sbi->s_mount_opt, GRPID); 479 break; 480 case Opt_nogrpid: 481 clear_opt (sbi->s_mount_opt, GRPID); 482 break; 483 case Opt_resuid: 484 if (match_int(&args[0], &option)) 485 return 0; 486 uid = make_kuid(current_user_ns(), option); 487 if (!uid_valid(uid)) { 488 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option); 489 return 0; 490 491 } 492 sbi->s_resuid = uid; 493 break; 494 case Opt_resgid: 495 if (match_int(&args[0], &option)) 496 return 0; 497 gid = make_kgid(current_user_ns(), option); 498 if (!gid_valid(gid)) { 499 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option); 500 return 0; 501 } 502 sbi->s_resgid = gid; 503 break; 504 case Opt_sb: 505 /* handled by get_sb_block() instead of here */ 506 /* *sb_block = match_int(&args[0]); */ 507 break; 508 case Opt_err_panic: 509 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 510 clear_opt (sbi->s_mount_opt, ERRORS_RO); 511 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 512 break; 513 case Opt_err_ro: 514 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 515 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 516 set_opt (sbi->s_mount_opt, ERRORS_RO); 517 break; 518 case Opt_err_cont: 519 clear_opt (sbi->s_mount_opt, ERRORS_RO); 520 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 521 set_opt (sbi->s_mount_opt, ERRORS_CONT); 522 break; 523 case Opt_nouid32: 524 set_opt (sbi->s_mount_opt, NO_UID32); 525 break; 526 case Opt_nocheck: 527 clear_opt (sbi->s_mount_opt, CHECK); 528 break; 529 case Opt_debug: 530 set_opt (sbi->s_mount_opt, DEBUG); 531 break; 532 case Opt_oldalloc: 533 set_opt (sbi->s_mount_opt, OLDALLOC); 534 break; 535 case Opt_orlov: 536 clear_opt (sbi->s_mount_opt, OLDALLOC); 537 break; 538 case Opt_nobh: 539 set_opt (sbi->s_mount_opt, NOBH); 540 break; 541 #ifdef CONFIG_EXT2_FS_XATTR 542 case Opt_user_xattr: 543 set_opt (sbi->s_mount_opt, XATTR_USER); 544 break; 545 case Opt_nouser_xattr: 546 clear_opt (sbi->s_mount_opt, XATTR_USER); 547 break; 548 #else 549 case Opt_user_xattr: 550 case Opt_nouser_xattr: 551 ext2_msg(sb, KERN_INFO, "(no)user_xattr options" 552 "not supported"); 553 break; 554 #endif 555 #ifdef CONFIG_EXT2_FS_POSIX_ACL 556 case Opt_acl: 557 set_opt(sbi->s_mount_opt, POSIX_ACL); 558 break; 559 case Opt_noacl: 560 clear_opt(sbi->s_mount_opt, POSIX_ACL); 561 break; 562 #else 563 case Opt_acl: 564 case Opt_noacl: 565 ext2_msg(sb, KERN_INFO, 566 "(no)acl options not supported"); 567 break; 568 #endif 569 case Opt_xip: 570 ext2_msg(sb, KERN_INFO, "use dax instead of xip"); 571 set_opt(sbi->s_mount_opt, XIP); 572 /* Fall through */ 573 case Opt_dax: 574 #ifdef CONFIG_FS_DAX 575 ext2_msg(sb, KERN_WARNING, 576 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk"); 577 set_opt(sbi->s_mount_opt, DAX); 578 #else 579 ext2_msg(sb, KERN_INFO, "dax option not supported"); 580 #endif 581 break; 582 583 #if defined(CONFIG_QUOTA) 584 case Opt_quota: 585 case Opt_usrquota: 586 set_opt(sbi->s_mount_opt, USRQUOTA); 587 break; 588 589 case Opt_grpquota: 590 set_opt(sbi->s_mount_opt, GRPQUOTA); 591 break; 592 #else 593 case Opt_quota: 594 case Opt_usrquota: 595 case Opt_grpquota: 596 ext2_msg(sb, KERN_INFO, 597 "quota operations not supported"); 598 break; 599 #endif 600 601 case Opt_reservation: 602 set_opt(sbi->s_mount_opt, RESERVATION); 603 ext2_msg(sb, KERN_INFO, "reservations ON"); 604 break; 605 case Opt_noreservation: 606 clear_opt(sbi->s_mount_opt, RESERVATION); 607 ext2_msg(sb, KERN_INFO, "reservations OFF"); 608 break; 609 case Opt_ignore: 610 break; 611 default: 612 return 0; 613 } 614 } 615 return 1; 616 } 617 618 static int ext2_setup_super (struct super_block * sb, 619 struct ext2_super_block * es, 620 int read_only) 621 { 622 int res = 0; 623 struct ext2_sb_info *sbi = EXT2_SB(sb); 624 625 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 626 ext2_msg(sb, KERN_ERR, 627 "error: revision level too high, " 628 "forcing read-only mode"); 629 res = MS_RDONLY; 630 } 631 if (read_only) 632 return res; 633 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 634 ext2_msg(sb, KERN_WARNING, 635 "warning: mounting unchecked fs, " 636 "running e2fsck is recommended"); 637 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 638 ext2_msg(sb, KERN_WARNING, 639 "warning: mounting fs with errors, " 640 "running e2fsck is recommended"); 641 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 642 le16_to_cpu(es->s_mnt_count) >= 643 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 644 ext2_msg(sb, KERN_WARNING, 645 "warning: maximal mount count reached, " 646 "running e2fsck is recommended"); 647 else if (le32_to_cpu(es->s_checkinterval) && 648 (le32_to_cpu(es->s_lastcheck) + 649 le32_to_cpu(es->s_checkinterval) <= get_seconds())) 650 ext2_msg(sb, KERN_WARNING, 651 "warning: checktime reached, " 652 "running e2fsck is recommended"); 653 if (!le16_to_cpu(es->s_max_mnt_count)) 654 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 655 le16_add_cpu(&es->s_mnt_count, 1); 656 if (test_opt (sb, DEBUG)) 657 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, " 658 "bpg=%lu, ipg=%lu, mo=%04lx]", 659 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 660 sbi->s_frag_size, 661 sbi->s_groups_count, 662 EXT2_BLOCKS_PER_GROUP(sb), 663 EXT2_INODES_PER_GROUP(sb), 664 sbi->s_mount_opt); 665 return res; 666 } 667 668 static int ext2_check_descriptors(struct super_block *sb) 669 { 670 int i; 671 struct ext2_sb_info *sbi = EXT2_SB(sb); 672 673 ext2_debug ("Checking group descriptors"); 674 675 for (i = 0; i < sbi->s_groups_count; i++) { 676 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 677 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 678 ext2_fsblk_t last_block; 679 680 if (i == sbi->s_groups_count - 1) 681 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 682 else 683 last_block = first_block + 684 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 685 686 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 687 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 688 { 689 ext2_error (sb, "ext2_check_descriptors", 690 "Block bitmap for group %d" 691 " not in group (block %lu)!", 692 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 693 return 0; 694 } 695 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 696 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 697 { 698 ext2_error (sb, "ext2_check_descriptors", 699 "Inode bitmap for group %d" 700 " not in group (block %lu)!", 701 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 702 return 0; 703 } 704 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 705 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 706 last_block) 707 { 708 ext2_error (sb, "ext2_check_descriptors", 709 "Inode table for group %d" 710 " not in group (block %lu)!", 711 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 712 return 0; 713 } 714 } 715 return 1; 716 } 717 718 /* 719 * Maximal file size. There is a direct, and {,double-,triple-}indirect 720 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 721 * We need to be 1 filesystem block less than the 2^32 sector limit. 722 */ 723 static loff_t ext2_max_size(int bits) 724 { 725 loff_t res = EXT2_NDIR_BLOCKS; 726 int meta_blocks; 727 loff_t upper_limit; 728 729 /* This is calculated to be the largest file size for a 730 * dense, file such that the total number of 731 * sectors in the file, including data and all indirect blocks, 732 * does not exceed 2^32 -1 733 * __u32 i_blocks representing the total number of 734 * 512 bytes blocks of the file 735 */ 736 upper_limit = (1LL << 32) - 1; 737 738 /* total blocks in file system block size */ 739 upper_limit >>= (bits - 9); 740 741 742 /* indirect blocks */ 743 meta_blocks = 1; 744 /* double indirect blocks */ 745 meta_blocks += 1 + (1LL << (bits-2)); 746 /* tripple indirect blocks */ 747 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2))); 748 749 upper_limit -= meta_blocks; 750 upper_limit <<= bits; 751 752 res += 1LL << (bits-2); 753 res += 1LL << (2*(bits-2)); 754 res += 1LL << (3*(bits-2)); 755 res <<= bits; 756 if (res > upper_limit) 757 res = upper_limit; 758 759 if (res > MAX_LFS_FILESIZE) 760 res = MAX_LFS_FILESIZE; 761 762 return res; 763 } 764 765 static unsigned long descriptor_loc(struct super_block *sb, 766 unsigned long logic_sb_block, 767 int nr) 768 { 769 struct ext2_sb_info *sbi = EXT2_SB(sb); 770 unsigned long bg, first_meta_bg; 771 int has_super = 0; 772 773 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 774 775 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 776 nr < first_meta_bg) 777 return (logic_sb_block + nr + 1); 778 bg = sbi->s_desc_per_block * nr; 779 if (ext2_bg_has_super(sb, bg)) 780 has_super = 1; 781 782 return ext2_group_first_block_no(sb, bg) + has_super; 783 } 784 785 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 786 { 787 struct buffer_head * bh; 788 struct ext2_sb_info * sbi; 789 struct ext2_super_block * es; 790 struct inode *root; 791 unsigned long block; 792 unsigned long sb_block = get_sb_block(&data); 793 unsigned long logic_sb_block; 794 unsigned long offset = 0; 795 unsigned long def_mount_opts; 796 long ret = -EINVAL; 797 int blocksize = BLOCK_SIZE; 798 int db_count; 799 int i, j; 800 __le32 features; 801 int err; 802 803 err = -ENOMEM; 804 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 805 if (!sbi) 806 goto failed; 807 808 sbi->s_blockgroup_lock = 809 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 810 if (!sbi->s_blockgroup_lock) { 811 kfree(sbi); 812 goto failed; 813 } 814 sb->s_fs_info = sbi; 815 sbi->s_sb_block = sb_block; 816 817 spin_lock_init(&sbi->s_lock); 818 819 /* 820 * See what the current blocksize for the device is, and 821 * use that as the blocksize. Otherwise (or if the blocksize 822 * is smaller than the default) use the default. 823 * This is important for devices that have a hardware 824 * sectorsize that is larger than the default. 825 */ 826 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 827 if (!blocksize) { 828 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 829 goto failed_sbi; 830 } 831 832 /* 833 * If the superblock doesn't start on a hardware sector boundary, 834 * calculate the offset. 835 */ 836 if (blocksize != BLOCK_SIZE) { 837 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 838 offset = (sb_block*BLOCK_SIZE) % blocksize; 839 } else { 840 logic_sb_block = sb_block; 841 } 842 843 if (!(bh = sb_bread(sb, logic_sb_block))) { 844 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 845 goto failed_sbi; 846 } 847 /* 848 * Note: s_es must be initialized as soon as possible because 849 * some ext2 macro-instructions depend on its value 850 */ 851 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 852 sbi->s_es = es; 853 sb->s_magic = le16_to_cpu(es->s_magic); 854 855 if (sb->s_magic != EXT2_SUPER_MAGIC) 856 goto cantfind_ext2; 857 858 /* Set defaults before we parse the mount options */ 859 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 860 if (def_mount_opts & EXT2_DEFM_DEBUG) 861 set_opt(sbi->s_mount_opt, DEBUG); 862 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 863 set_opt(sbi->s_mount_opt, GRPID); 864 if (def_mount_opts & EXT2_DEFM_UID16) 865 set_opt(sbi->s_mount_opt, NO_UID32); 866 #ifdef CONFIG_EXT2_FS_XATTR 867 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 868 set_opt(sbi->s_mount_opt, XATTR_USER); 869 #endif 870 #ifdef CONFIG_EXT2_FS_POSIX_ACL 871 if (def_mount_opts & EXT2_DEFM_ACL) 872 set_opt(sbi->s_mount_opt, POSIX_ACL); 873 #endif 874 875 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 876 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 877 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 878 set_opt(sbi->s_mount_opt, ERRORS_CONT); 879 else 880 set_opt(sbi->s_mount_opt, ERRORS_RO); 881 882 sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid)); 883 sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid)); 884 885 set_opt(sbi->s_mount_opt, RESERVATION); 886 887 if (!parse_options((char *) data, sb)) 888 goto failed_mount; 889 890 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 891 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 892 MS_POSIXACL : 0); 893 sb->s_iflags |= SB_I_CGROUPWB; 894 895 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 896 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 897 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 898 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 899 ext2_msg(sb, KERN_WARNING, 900 "warning: feature flags set on rev 0 fs, " 901 "running e2fsck is recommended"); 902 /* 903 * Check feature flags regardless of the revision level, since we 904 * previously didn't change the revision level when setting the flags, 905 * so there is a chance incompat flags are set on a rev 0 filesystem. 906 */ 907 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 908 if (features) { 909 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 910 "unsupported optional features (%x)", 911 le32_to_cpu(features)); 912 goto failed_mount; 913 } 914 if (!(sb->s_flags & MS_RDONLY) && 915 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 916 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 917 "unsupported optional features (%x)", 918 le32_to_cpu(features)); 919 goto failed_mount; 920 } 921 922 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 923 924 if (sbi->s_mount_opt & EXT2_MOUNT_DAX) { 925 err = bdev_dax_supported(sb, blocksize); 926 if (err) 927 goto failed_mount; 928 } 929 930 /* If the blocksize doesn't match, re-read the thing.. */ 931 if (sb->s_blocksize != blocksize) { 932 brelse(bh); 933 934 if (!sb_set_blocksize(sb, blocksize)) { 935 ext2_msg(sb, KERN_ERR, 936 "error: bad blocksize %d", blocksize); 937 goto failed_sbi; 938 } 939 940 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 941 offset = (sb_block*BLOCK_SIZE) % blocksize; 942 bh = sb_bread(sb, logic_sb_block); 943 if(!bh) { 944 ext2_msg(sb, KERN_ERR, "error: couldn't read" 945 "superblock on 2nd try"); 946 goto failed_sbi; 947 } 948 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 949 sbi->s_es = es; 950 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 951 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 952 goto failed_mount; 953 } 954 } 955 956 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 957 sb->s_max_links = EXT2_LINK_MAX; 958 959 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 960 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 961 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 962 } else { 963 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 964 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 965 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 966 !is_power_of_2(sbi->s_inode_size) || 967 (sbi->s_inode_size > blocksize)) { 968 ext2_msg(sb, KERN_ERR, 969 "error: unsupported inode size: %d", 970 sbi->s_inode_size); 971 goto failed_mount; 972 } 973 } 974 975 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 976 le32_to_cpu(es->s_log_frag_size); 977 if (sbi->s_frag_size == 0) 978 goto cantfind_ext2; 979 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 980 981 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 982 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 983 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 984 985 if (EXT2_INODE_SIZE(sb) == 0) 986 goto cantfind_ext2; 987 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 988 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 989 goto cantfind_ext2; 990 sbi->s_itb_per_group = sbi->s_inodes_per_group / 991 sbi->s_inodes_per_block; 992 sbi->s_desc_per_block = sb->s_blocksize / 993 sizeof (struct ext2_group_desc); 994 sbi->s_sbh = bh; 995 sbi->s_mount_state = le16_to_cpu(es->s_state); 996 sbi->s_addr_per_block_bits = 997 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 998 sbi->s_desc_per_block_bits = 999 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 1000 1001 if (sb->s_magic != EXT2_SUPER_MAGIC) 1002 goto cantfind_ext2; 1003 1004 if (sb->s_blocksize != bh->b_size) { 1005 if (!silent) 1006 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 1007 goto failed_mount; 1008 } 1009 1010 if (sb->s_blocksize != sbi->s_frag_size) { 1011 ext2_msg(sb, KERN_ERR, 1012 "error: fragsize %lu != blocksize %lu" 1013 "(not supported yet)", 1014 sbi->s_frag_size, sb->s_blocksize); 1015 goto failed_mount; 1016 } 1017 1018 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 1019 ext2_msg(sb, KERN_ERR, 1020 "error: #blocks per group too big: %lu", 1021 sbi->s_blocks_per_group); 1022 goto failed_mount; 1023 } 1024 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 1025 ext2_msg(sb, KERN_ERR, 1026 "error: #fragments per group too big: %lu", 1027 sbi->s_frags_per_group); 1028 goto failed_mount; 1029 } 1030 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 1031 ext2_msg(sb, KERN_ERR, 1032 "error: #inodes per group too big: %lu", 1033 sbi->s_inodes_per_group); 1034 goto failed_mount; 1035 } 1036 1037 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 1038 goto cantfind_ext2; 1039 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1040 le32_to_cpu(es->s_first_data_block) - 1) 1041 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1042 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1043 EXT2_DESC_PER_BLOCK(sb); 1044 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 1045 if (sbi->s_group_desc == NULL) { 1046 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1047 goto failed_mount; 1048 } 1049 bgl_lock_init(sbi->s_blockgroup_lock); 1050 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1051 if (!sbi->s_debts) { 1052 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1053 goto failed_mount_group_desc; 1054 } 1055 for (i = 0; i < db_count; i++) { 1056 block = descriptor_loc(sb, logic_sb_block, i); 1057 sbi->s_group_desc[i] = sb_bread(sb, block); 1058 if (!sbi->s_group_desc[i]) { 1059 for (j = 0; j < i; j++) 1060 brelse (sbi->s_group_desc[j]); 1061 ext2_msg(sb, KERN_ERR, 1062 "error: unable to read group descriptors"); 1063 goto failed_mount_group_desc; 1064 } 1065 } 1066 if (!ext2_check_descriptors (sb)) { 1067 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1068 goto failed_mount2; 1069 } 1070 sbi->s_gdb_count = db_count; 1071 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1072 spin_lock_init(&sbi->s_next_gen_lock); 1073 1074 /* per fileystem reservation list head & lock */ 1075 spin_lock_init(&sbi->s_rsv_window_lock); 1076 sbi->s_rsv_window_root = RB_ROOT; 1077 /* 1078 * Add a single, static dummy reservation to the start of the 1079 * reservation window list --- it gives us a placeholder for 1080 * append-at-start-of-list which makes the allocation logic 1081 * _much_ simpler. 1082 */ 1083 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1084 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1085 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1086 sbi->s_rsv_window_head.rsv_goal_size = 0; 1087 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1088 1089 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1090 ext2_count_free_blocks(sb), GFP_KERNEL); 1091 if (!err) { 1092 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1093 ext2_count_free_inodes(sb), GFP_KERNEL); 1094 } 1095 if (!err) { 1096 err = percpu_counter_init(&sbi->s_dirs_counter, 1097 ext2_count_dirs(sb), GFP_KERNEL); 1098 } 1099 if (err) { 1100 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1101 goto failed_mount3; 1102 } 1103 1104 #ifdef CONFIG_EXT2_FS_XATTR 1105 sbi->s_mb_cache = ext2_xattr_create_cache(); 1106 if (!sbi->s_mb_cache) { 1107 ext2_msg(sb, KERN_ERR, "Failed to create an mb_cache"); 1108 goto failed_mount3; 1109 } 1110 #endif 1111 /* 1112 * set up enough so that it can read an inode 1113 */ 1114 sb->s_op = &ext2_sops; 1115 sb->s_export_op = &ext2_export_ops; 1116 sb->s_xattr = ext2_xattr_handlers; 1117 1118 #ifdef CONFIG_QUOTA 1119 sb->dq_op = &dquot_operations; 1120 sb->s_qcop = &dquot_quotactl_ops; 1121 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP; 1122 #endif 1123 1124 root = ext2_iget(sb, EXT2_ROOT_INO); 1125 if (IS_ERR(root)) { 1126 ret = PTR_ERR(root); 1127 goto failed_mount3; 1128 } 1129 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1130 iput(root); 1131 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1132 goto failed_mount3; 1133 } 1134 1135 sb->s_root = d_make_root(root); 1136 if (!sb->s_root) { 1137 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1138 ret = -ENOMEM; 1139 goto failed_mount3; 1140 } 1141 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1142 ext2_msg(sb, KERN_WARNING, 1143 "warning: mounting ext3 filesystem as ext2"); 1144 if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY)) 1145 sb->s_flags |= MS_RDONLY; 1146 ext2_write_super(sb); 1147 return 0; 1148 1149 cantfind_ext2: 1150 if (!silent) 1151 ext2_msg(sb, KERN_ERR, 1152 "error: can't find an ext2 filesystem on dev %s.", 1153 sb->s_id); 1154 goto failed_mount; 1155 failed_mount3: 1156 if (sbi->s_mb_cache) 1157 ext2_xattr_destroy_cache(sbi->s_mb_cache); 1158 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1159 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1160 percpu_counter_destroy(&sbi->s_dirs_counter); 1161 failed_mount2: 1162 for (i = 0; i < db_count; i++) 1163 brelse(sbi->s_group_desc[i]); 1164 failed_mount_group_desc: 1165 kfree(sbi->s_group_desc); 1166 kfree(sbi->s_debts); 1167 failed_mount: 1168 brelse(bh); 1169 failed_sbi: 1170 sb->s_fs_info = NULL; 1171 kfree(sbi->s_blockgroup_lock); 1172 kfree(sbi); 1173 failed: 1174 return ret; 1175 } 1176 1177 static void ext2_clear_super_error(struct super_block *sb) 1178 { 1179 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1180 1181 if (buffer_write_io_error(sbh)) { 1182 /* 1183 * Oh, dear. A previous attempt to write the 1184 * superblock failed. This could happen because the 1185 * USB device was yanked out. Or it could happen to 1186 * be a transient write error and maybe the block will 1187 * be remapped. Nothing we can do but to retry the 1188 * write and hope for the best. 1189 */ 1190 ext2_msg(sb, KERN_ERR, 1191 "previous I/O error to superblock detected\n"); 1192 clear_buffer_write_io_error(sbh); 1193 set_buffer_uptodate(sbh); 1194 } 1195 } 1196 1197 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, 1198 int wait) 1199 { 1200 ext2_clear_super_error(sb); 1201 spin_lock(&EXT2_SB(sb)->s_lock); 1202 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1203 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1204 es->s_wtime = cpu_to_le32(get_seconds()); 1205 /* unlock before we do IO */ 1206 spin_unlock(&EXT2_SB(sb)->s_lock); 1207 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1208 if (wait) 1209 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1210 } 1211 1212 /* 1213 * In the second extended file system, it is not necessary to 1214 * write the super block since we use a mapping of the 1215 * disk super block in a buffer. 1216 * 1217 * However, this function is still used to set the fs valid 1218 * flags to 0. We need to set this flag to 0 since the fs 1219 * may have been checked while mounted and e2fsck may have 1220 * set s_state to EXT2_VALID_FS after some corrections. 1221 */ 1222 static int ext2_sync_fs(struct super_block *sb, int wait) 1223 { 1224 struct ext2_sb_info *sbi = EXT2_SB(sb); 1225 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1226 1227 /* 1228 * Write quota structures to quota file, sync_blockdev() will write 1229 * them to disk later 1230 */ 1231 dquot_writeback_dquots(sb, -1); 1232 1233 spin_lock(&sbi->s_lock); 1234 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1235 ext2_debug("setting valid to 0\n"); 1236 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1237 } 1238 spin_unlock(&sbi->s_lock); 1239 ext2_sync_super(sb, es, wait); 1240 return 0; 1241 } 1242 1243 static int ext2_freeze(struct super_block *sb) 1244 { 1245 struct ext2_sb_info *sbi = EXT2_SB(sb); 1246 1247 /* 1248 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared 1249 * because we have unattached inodes and thus filesystem is not fully 1250 * consistent. 1251 */ 1252 if (atomic_long_read(&sb->s_remove_count)) { 1253 ext2_sync_fs(sb, 1); 1254 return 0; 1255 } 1256 /* Set EXT2_FS_VALID flag */ 1257 spin_lock(&sbi->s_lock); 1258 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); 1259 spin_unlock(&sbi->s_lock); 1260 ext2_sync_super(sb, sbi->s_es, 1); 1261 1262 return 0; 1263 } 1264 1265 static int ext2_unfreeze(struct super_block *sb) 1266 { 1267 /* Just write sb to clear EXT2_VALID_FS flag */ 1268 ext2_write_super(sb); 1269 1270 return 0; 1271 } 1272 1273 void ext2_write_super(struct super_block *sb) 1274 { 1275 if (!(sb->s_flags & MS_RDONLY)) 1276 ext2_sync_fs(sb, 1); 1277 } 1278 1279 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1280 { 1281 struct ext2_sb_info * sbi = EXT2_SB(sb); 1282 struct ext2_super_block * es; 1283 struct ext2_mount_options old_opts; 1284 unsigned long old_sb_flags; 1285 int err; 1286 1287 sync_filesystem(sb); 1288 spin_lock(&sbi->s_lock); 1289 1290 /* Store the old options */ 1291 old_sb_flags = sb->s_flags; 1292 old_opts.s_mount_opt = sbi->s_mount_opt; 1293 old_opts.s_resuid = sbi->s_resuid; 1294 old_opts.s_resgid = sbi->s_resgid; 1295 1296 /* 1297 * Allow the "check" option to be passed as a remount option. 1298 */ 1299 if (!parse_options(data, sb)) { 1300 err = -EINVAL; 1301 goto restore_opts; 1302 } 1303 1304 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1305 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1306 1307 es = sbi->s_es; 1308 if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT2_MOUNT_DAX) { 1309 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1310 "dax flag with busy inodes while remounting"); 1311 sbi->s_mount_opt ^= EXT2_MOUNT_DAX; 1312 } 1313 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { 1314 spin_unlock(&sbi->s_lock); 1315 return 0; 1316 } 1317 if (*flags & MS_RDONLY) { 1318 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1319 !(sbi->s_mount_state & EXT2_VALID_FS)) { 1320 spin_unlock(&sbi->s_lock); 1321 return 0; 1322 } 1323 1324 /* 1325 * OK, we are remounting a valid rw partition rdonly, so set 1326 * the rdonly flag and then mark the partition as valid again. 1327 */ 1328 es->s_state = cpu_to_le16(sbi->s_mount_state); 1329 es->s_mtime = cpu_to_le32(get_seconds()); 1330 spin_unlock(&sbi->s_lock); 1331 1332 err = dquot_suspend(sb, -1); 1333 if (err < 0) { 1334 spin_lock(&sbi->s_lock); 1335 goto restore_opts; 1336 } 1337 1338 ext2_sync_super(sb, es, 1); 1339 } else { 1340 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1341 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1342 if (ret) { 1343 ext2_msg(sb, KERN_WARNING, 1344 "warning: couldn't remount RDWR because of " 1345 "unsupported optional features (%x).", 1346 le32_to_cpu(ret)); 1347 err = -EROFS; 1348 goto restore_opts; 1349 } 1350 /* 1351 * Mounting a RDONLY partition read-write, so reread and 1352 * store the current valid flag. (It may have been changed 1353 * by e2fsck since we originally mounted the partition.) 1354 */ 1355 sbi->s_mount_state = le16_to_cpu(es->s_state); 1356 if (!ext2_setup_super (sb, es, 0)) 1357 sb->s_flags &= ~MS_RDONLY; 1358 spin_unlock(&sbi->s_lock); 1359 1360 ext2_write_super(sb); 1361 1362 dquot_resume(sb, -1); 1363 } 1364 1365 return 0; 1366 restore_opts: 1367 sbi->s_mount_opt = old_opts.s_mount_opt; 1368 sbi->s_resuid = old_opts.s_resuid; 1369 sbi->s_resgid = old_opts.s_resgid; 1370 sb->s_flags = old_sb_flags; 1371 spin_unlock(&sbi->s_lock); 1372 return err; 1373 } 1374 1375 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1376 { 1377 struct super_block *sb = dentry->d_sb; 1378 struct ext2_sb_info *sbi = EXT2_SB(sb); 1379 struct ext2_super_block *es = sbi->s_es; 1380 u64 fsid; 1381 1382 spin_lock(&sbi->s_lock); 1383 1384 if (test_opt (sb, MINIX_DF)) 1385 sbi->s_overhead_last = 0; 1386 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1387 unsigned long i, overhead = 0; 1388 smp_rmb(); 1389 1390 /* 1391 * Compute the overhead (FS structures). This is constant 1392 * for a given filesystem unless the number of block groups 1393 * changes so we cache the previous value until it does. 1394 */ 1395 1396 /* 1397 * All of the blocks before first_data_block are 1398 * overhead 1399 */ 1400 overhead = le32_to_cpu(es->s_first_data_block); 1401 1402 /* 1403 * Add the overhead attributed to the superblock and 1404 * block group descriptors. If the sparse superblocks 1405 * feature is turned on, then not all groups have this. 1406 */ 1407 for (i = 0; i < sbi->s_groups_count; i++) 1408 overhead += ext2_bg_has_super(sb, i) + 1409 ext2_bg_num_gdb(sb, i); 1410 1411 /* 1412 * Every block group has an inode bitmap, a block 1413 * bitmap, and an inode table. 1414 */ 1415 overhead += (sbi->s_groups_count * 1416 (2 + sbi->s_itb_per_group)); 1417 sbi->s_overhead_last = overhead; 1418 smp_wmb(); 1419 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1420 } 1421 1422 buf->f_type = EXT2_SUPER_MAGIC; 1423 buf->f_bsize = sb->s_blocksize; 1424 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1425 buf->f_bfree = ext2_count_free_blocks(sb); 1426 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1427 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1428 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1429 buf->f_bavail = 0; 1430 buf->f_files = le32_to_cpu(es->s_inodes_count); 1431 buf->f_ffree = ext2_count_free_inodes(sb); 1432 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1433 buf->f_namelen = EXT2_NAME_LEN; 1434 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1435 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1436 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1437 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1438 spin_unlock(&sbi->s_lock); 1439 return 0; 1440 } 1441 1442 static struct dentry *ext2_mount(struct file_system_type *fs_type, 1443 int flags, const char *dev_name, void *data) 1444 { 1445 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1446 } 1447 1448 #ifdef CONFIG_QUOTA 1449 1450 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1451 * acquiring the locks... As quota files are never truncated and quota code 1452 * itself serializes the operations (and no one else should touch the files) 1453 * we don't have to be afraid of races */ 1454 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1455 size_t len, loff_t off) 1456 { 1457 struct inode *inode = sb_dqopt(sb)->files[type]; 1458 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1459 int err = 0; 1460 int offset = off & (sb->s_blocksize - 1); 1461 int tocopy; 1462 size_t toread; 1463 struct buffer_head tmp_bh; 1464 struct buffer_head *bh; 1465 loff_t i_size = i_size_read(inode); 1466 1467 if (off > i_size) 1468 return 0; 1469 if (off+len > i_size) 1470 len = i_size-off; 1471 toread = len; 1472 while (toread > 0) { 1473 tocopy = sb->s_blocksize - offset < toread ? 1474 sb->s_blocksize - offset : toread; 1475 1476 tmp_bh.b_state = 0; 1477 tmp_bh.b_size = sb->s_blocksize; 1478 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1479 if (err < 0) 1480 return err; 1481 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1482 memset(data, 0, tocopy); 1483 else { 1484 bh = sb_bread(sb, tmp_bh.b_blocknr); 1485 if (!bh) 1486 return -EIO; 1487 memcpy(data, bh->b_data+offset, tocopy); 1488 brelse(bh); 1489 } 1490 offset = 0; 1491 toread -= tocopy; 1492 data += tocopy; 1493 blk++; 1494 } 1495 return len; 1496 } 1497 1498 /* Write to quotafile */ 1499 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1500 const char *data, size_t len, loff_t off) 1501 { 1502 struct inode *inode = sb_dqopt(sb)->files[type]; 1503 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1504 int err = 0; 1505 int offset = off & (sb->s_blocksize - 1); 1506 int tocopy; 1507 size_t towrite = len; 1508 struct buffer_head tmp_bh; 1509 struct buffer_head *bh; 1510 1511 while (towrite > 0) { 1512 tocopy = sb->s_blocksize - offset < towrite ? 1513 sb->s_blocksize - offset : towrite; 1514 1515 tmp_bh.b_state = 0; 1516 tmp_bh.b_size = sb->s_blocksize; 1517 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1518 if (err < 0) 1519 goto out; 1520 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1521 bh = sb_bread(sb, tmp_bh.b_blocknr); 1522 else 1523 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1524 if (unlikely(!bh)) { 1525 err = -EIO; 1526 goto out; 1527 } 1528 lock_buffer(bh); 1529 memcpy(bh->b_data+offset, data, tocopy); 1530 flush_dcache_page(bh->b_page); 1531 set_buffer_uptodate(bh); 1532 mark_buffer_dirty(bh); 1533 unlock_buffer(bh); 1534 brelse(bh); 1535 offset = 0; 1536 towrite -= tocopy; 1537 data += tocopy; 1538 blk++; 1539 } 1540 out: 1541 if (len == towrite) 1542 return err; 1543 if (inode->i_size < off+len-towrite) 1544 i_size_write(inode, off+len-towrite); 1545 inode->i_version++; 1546 inode->i_mtime = inode->i_ctime = current_time(inode); 1547 mark_inode_dirty(inode); 1548 return len - towrite; 1549 } 1550 1551 #endif 1552 1553 static struct file_system_type ext2_fs_type = { 1554 .owner = THIS_MODULE, 1555 .name = "ext2", 1556 .mount = ext2_mount, 1557 .kill_sb = kill_block_super, 1558 .fs_flags = FS_REQUIRES_DEV, 1559 }; 1560 MODULE_ALIAS_FS("ext2"); 1561 1562 static int __init init_ext2_fs(void) 1563 { 1564 int err; 1565 1566 err = init_inodecache(); 1567 if (err) 1568 return err; 1569 err = register_filesystem(&ext2_fs_type); 1570 if (err) 1571 goto out; 1572 return 0; 1573 out: 1574 destroy_inodecache(); 1575 return err; 1576 } 1577 1578 static void __exit exit_ext2_fs(void) 1579 { 1580 unregister_filesystem(&ext2_fs_type); 1581 destroy_inodecache(); 1582 } 1583 1584 MODULE_AUTHOR("Remy Card and others"); 1585 MODULE_DESCRIPTION("Second Extended Filesystem"); 1586 MODULE_LICENSE("GPL"); 1587 module_init(init_ext2_fs) 1588 module_exit(exit_ext2_fs) 1589