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 #include "xip.h" 39 40 static void ext2_sync_super(struct super_block *sb, 41 struct ext2_super_block *es, int wait); 42 static int ext2_remount (struct super_block * sb, int * flags, char * data); 43 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf); 44 static int ext2_sync_fs(struct super_block *sb, int wait); 45 static int ext2_freeze(struct super_block *sb); 46 static int ext2_unfreeze(struct super_block *sb); 47 48 void ext2_error(struct super_block *sb, const char *function, 49 const char *fmt, ...) 50 { 51 struct va_format vaf; 52 va_list args; 53 struct ext2_sb_info *sbi = EXT2_SB(sb); 54 struct ext2_super_block *es = sbi->s_es; 55 56 if (!(sb->s_flags & MS_RDONLY)) { 57 spin_lock(&sbi->s_lock); 58 sbi->s_mount_state |= EXT2_ERROR_FS; 59 es->s_state |= cpu_to_le16(EXT2_ERROR_FS); 60 spin_unlock(&sbi->s_lock); 61 ext2_sync_super(sb, es, 1); 62 } 63 64 va_start(args, fmt); 65 66 vaf.fmt = fmt; 67 vaf.va = &args; 68 69 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n", 70 sb->s_id, function, &vaf); 71 72 va_end(args); 73 74 if (test_opt(sb, ERRORS_PANIC)) 75 panic("EXT2-fs: panic from previous error\n"); 76 if (test_opt(sb, ERRORS_RO)) { 77 ext2_msg(sb, KERN_CRIT, 78 "error: remounting filesystem read-only"); 79 sb->s_flags |= MS_RDONLY; 80 } 81 } 82 83 void ext2_msg(struct super_block *sb, const char *prefix, 84 const char *fmt, ...) 85 { 86 struct va_format vaf; 87 va_list args; 88 89 va_start(args, fmt); 90 91 vaf.fmt = fmt; 92 vaf.va = &args; 93 94 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf); 95 96 va_end(args); 97 } 98 99 /* 100 * This must be called with sbi->s_lock held. 101 */ 102 void ext2_update_dynamic_rev(struct super_block *sb) 103 { 104 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 105 106 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) 107 return; 108 109 ext2_msg(sb, KERN_WARNING, 110 "warning: updating to rev %d because of " 111 "new feature flag, running e2fsck is recommended", 112 EXT2_DYNAMIC_REV); 113 114 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); 115 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); 116 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); 117 /* leave es->s_feature_*compat flags alone */ 118 /* es->s_uuid will be set by e2fsck if empty */ 119 120 /* 121 * The rest of the superblock fields should be zero, and if not it 122 * means they are likely already in use, so leave them alone. We 123 * can leave it up to e2fsck to clean up any inconsistencies there. 124 */ 125 } 126 127 static void ext2_put_super (struct super_block * sb) 128 { 129 int db_count; 130 int i; 131 struct ext2_sb_info *sbi = EXT2_SB(sb); 132 133 dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 134 135 ext2_xattr_put_super(sb); 136 if (!(sb->s_flags & MS_RDONLY)) { 137 struct ext2_super_block *es = sbi->s_es; 138 139 spin_lock(&sbi->s_lock); 140 es->s_state = cpu_to_le16(sbi->s_mount_state); 141 spin_unlock(&sbi->s_lock); 142 ext2_sync_super(sb, es, 1); 143 } 144 db_count = sbi->s_gdb_count; 145 for (i = 0; i < db_count; i++) 146 if (sbi->s_group_desc[i]) 147 brelse (sbi->s_group_desc[i]); 148 kfree(sbi->s_group_desc); 149 kfree(sbi->s_debts); 150 percpu_counter_destroy(&sbi->s_freeblocks_counter); 151 percpu_counter_destroy(&sbi->s_freeinodes_counter); 152 percpu_counter_destroy(&sbi->s_dirs_counter); 153 brelse (sbi->s_sbh); 154 sb->s_fs_info = NULL; 155 kfree(sbi->s_blockgroup_lock); 156 kfree(sbi); 157 } 158 159 static struct kmem_cache * ext2_inode_cachep; 160 161 static struct inode *ext2_alloc_inode(struct super_block *sb) 162 { 163 struct ext2_inode_info *ei; 164 ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL); 165 if (!ei) 166 return NULL; 167 ei->i_block_alloc_info = NULL; 168 ei->vfs_inode.i_version = 1; 169 #ifdef CONFIG_QUOTA 170 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot)); 171 #endif 172 173 return &ei->vfs_inode; 174 } 175 176 static void ext2_i_callback(struct rcu_head *head) 177 { 178 struct inode *inode = container_of(head, struct inode, i_rcu); 179 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 180 } 181 182 static void ext2_destroy_inode(struct inode *inode) 183 { 184 call_rcu(&inode->i_rcu, ext2_i_callback); 185 } 186 187 static void init_once(void *foo) 188 { 189 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 190 191 rwlock_init(&ei->i_meta_lock); 192 #ifdef CONFIG_EXT2_FS_XATTR 193 init_rwsem(&ei->xattr_sem); 194 #endif 195 mutex_init(&ei->truncate_mutex); 196 inode_init_once(&ei->vfs_inode); 197 } 198 199 static int __init init_inodecache(void) 200 { 201 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 202 sizeof(struct ext2_inode_info), 203 0, (SLAB_RECLAIM_ACCOUNT| 204 SLAB_MEM_SPREAD), 205 init_once); 206 if (ext2_inode_cachep == NULL) 207 return -ENOMEM; 208 return 0; 209 } 210 211 static void destroy_inodecache(void) 212 { 213 /* 214 * Make sure all delayed rcu free inodes are flushed before we 215 * destroy cache. 216 */ 217 rcu_barrier(); 218 kmem_cache_destroy(ext2_inode_cachep); 219 } 220 221 static int ext2_show_options(struct seq_file *seq, struct dentry *root) 222 { 223 struct super_block *sb = root->d_sb; 224 struct ext2_sb_info *sbi = EXT2_SB(sb); 225 struct ext2_super_block *es = sbi->s_es; 226 unsigned long def_mount_opts; 227 228 spin_lock(&sbi->s_lock); 229 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 230 231 if (sbi->s_sb_block != 1) 232 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 233 if (test_opt(sb, MINIX_DF)) 234 seq_puts(seq, ",minixdf"); 235 if (test_opt(sb, GRPID)) 236 seq_puts(seq, ",grpid"); 237 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 238 seq_puts(seq, ",nogrpid"); 239 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) || 240 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 241 seq_printf(seq, ",resuid=%u", 242 from_kuid_munged(&init_user_ns, sbi->s_resuid)); 243 } 244 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) || 245 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 246 seq_printf(seq, ",resgid=%u", 247 from_kgid_munged(&init_user_ns, sbi->s_resgid)); 248 } 249 if (test_opt(sb, ERRORS_RO)) { 250 int def_errors = le16_to_cpu(es->s_errors); 251 252 if (def_errors == EXT2_ERRORS_PANIC || 253 def_errors == EXT2_ERRORS_CONTINUE) { 254 seq_puts(seq, ",errors=remount-ro"); 255 } 256 } 257 if (test_opt(sb, ERRORS_CONT)) 258 seq_puts(seq, ",errors=continue"); 259 if (test_opt(sb, ERRORS_PANIC)) 260 seq_puts(seq, ",errors=panic"); 261 if (test_opt(sb, NO_UID32)) 262 seq_puts(seq, ",nouid32"); 263 if (test_opt(sb, DEBUG)) 264 seq_puts(seq, ",debug"); 265 if (test_opt(sb, OLDALLOC)) 266 seq_puts(seq, ",oldalloc"); 267 268 #ifdef CONFIG_EXT2_FS_XATTR 269 if (test_opt(sb, XATTR_USER)) 270 seq_puts(seq, ",user_xattr"); 271 if (!test_opt(sb, XATTR_USER) && 272 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 273 seq_puts(seq, ",nouser_xattr"); 274 } 275 #endif 276 277 #ifdef CONFIG_EXT2_FS_POSIX_ACL 278 if (test_opt(sb, POSIX_ACL)) 279 seq_puts(seq, ",acl"); 280 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 281 seq_puts(seq, ",noacl"); 282 #endif 283 284 if (test_opt(sb, NOBH)) 285 seq_puts(seq, ",nobh"); 286 287 #if defined(CONFIG_QUOTA) 288 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 289 seq_puts(seq, ",usrquota"); 290 291 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 292 seq_puts(seq, ",grpquota"); 293 #endif 294 295 #if defined(CONFIG_EXT2_FS_XIP) 296 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 297 seq_puts(seq, ",xip"); 298 #endif 299 300 if (!test_opt(sb, RESERVATION)) 301 seq_puts(seq, ",noreservation"); 302 303 spin_unlock(&sbi->s_lock); 304 return 0; 305 } 306 307 #ifdef CONFIG_QUOTA 308 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 309 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 310 static struct dquot **ext2_get_dquots(struct inode *inode) 311 { 312 return EXT2_I(inode)->i_dquot; 313 } 314 #endif 315 316 static const struct super_operations ext2_sops = { 317 .alloc_inode = ext2_alloc_inode, 318 .destroy_inode = ext2_destroy_inode, 319 .write_inode = ext2_write_inode, 320 .evict_inode = ext2_evict_inode, 321 .put_super = ext2_put_super, 322 .sync_fs = ext2_sync_fs, 323 .freeze_fs = ext2_freeze, 324 .unfreeze_fs = ext2_unfreeze, 325 .statfs = ext2_statfs, 326 .remount_fs = ext2_remount, 327 .show_options = ext2_show_options, 328 #ifdef CONFIG_QUOTA 329 .quota_read = ext2_quota_read, 330 .quota_write = ext2_quota_write, 331 .get_dquots = ext2_get_dquots, 332 #endif 333 }; 334 335 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 336 u64 ino, u32 generation) 337 { 338 struct inode *inode; 339 340 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 341 return ERR_PTR(-ESTALE); 342 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 343 return ERR_PTR(-ESTALE); 344 345 /* 346 * ext2_iget isn't quite right if the inode is currently unallocated! 347 * However ext2_iget currently does appropriate checks to handle stale 348 * inodes so everything is OK. 349 */ 350 inode = ext2_iget(sb, ino); 351 if (IS_ERR(inode)) 352 return ERR_CAST(inode); 353 if (generation && inode->i_generation != generation) { 354 /* we didn't find the right inode.. */ 355 iput(inode); 356 return ERR_PTR(-ESTALE); 357 } 358 return inode; 359 } 360 361 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 362 int fh_len, int fh_type) 363 { 364 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 365 ext2_nfs_get_inode); 366 } 367 368 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 369 int fh_len, int fh_type) 370 { 371 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 372 ext2_nfs_get_inode); 373 } 374 375 static const struct export_operations ext2_export_ops = { 376 .fh_to_dentry = ext2_fh_to_dentry, 377 .fh_to_parent = ext2_fh_to_parent, 378 .get_parent = ext2_get_parent, 379 }; 380 381 static unsigned long get_sb_block(void **data) 382 { 383 unsigned long sb_block; 384 char *options = (char *) *data; 385 386 if (!options || strncmp(options, "sb=", 3) != 0) 387 return 1; /* Default location */ 388 options += 3; 389 sb_block = simple_strtoul(options, &options, 0); 390 if (*options && *options != ',') { 391 printk("EXT2-fs: Invalid sb specification: %s\n", 392 (char *) *data); 393 return 1; 394 } 395 if (*options == ',') 396 options++; 397 *data = (void *) options; 398 return sb_block; 399 } 400 401 enum { 402 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 403 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 404 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 405 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 406 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, 407 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 408 }; 409 410 static const match_table_t tokens = { 411 {Opt_bsd_df, "bsddf"}, 412 {Opt_minix_df, "minixdf"}, 413 {Opt_grpid, "grpid"}, 414 {Opt_grpid, "bsdgroups"}, 415 {Opt_nogrpid, "nogrpid"}, 416 {Opt_nogrpid, "sysvgroups"}, 417 {Opt_resgid, "resgid=%u"}, 418 {Opt_resuid, "resuid=%u"}, 419 {Opt_sb, "sb=%u"}, 420 {Opt_err_cont, "errors=continue"}, 421 {Opt_err_panic, "errors=panic"}, 422 {Opt_err_ro, "errors=remount-ro"}, 423 {Opt_nouid32, "nouid32"}, 424 {Opt_nocheck, "check=none"}, 425 {Opt_nocheck, "nocheck"}, 426 {Opt_debug, "debug"}, 427 {Opt_oldalloc, "oldalloc"}, 428 {Opt_orlov, "orlov"}, 429 {Opt_nobh, "nobh"}, 430 {Opt_user_xattr, "user_xattr"}, 431 {Opt_nouser_xattr, "nouser_xattr"}, 432 {Opt_acl, "acl"}, 433 {Opt_noacl, "noacl"}, 434 {Opt_xip, "xip"}, 435 {Opt_grpquota, "grpquota"}, 436 {Opt_ignore, "noquota"}, 437 {Opt_quota, "quota"}, 438 {Opt_usrquota, "usrquota"}, 439 {Opt_reservation, "reservation"}, 440 {Opt_noreservation, "noreservation"}, 441 {Opt_err, NULL} 442 }; 443 444 static int parse_options(char *options, struct super_block *sb) 445 { 446 char *p; 447 struct ext2_sb_info *sbi = EXT2_SB(sb); 448 substring_t args[MAX_OPT_ARGS]; 449 int option; 450 kuid_t uid; 451 kgid_t gid; 452 453 if (!options) 454 return 1; 455 456 while ((p = strsep (&options, ",")) != NULL) { 457 int token; 458 if (!*p) 459 continue; 460 461 token = match_token(p, tokens, args); 462 switch (token) { 463 case Opt_bsd_df: 464 clear_opt (sbi->s_mount_opt, MINIX_DF); 465 break; 466 case Opt_minix_df: 467 set_opt (sbi->s_mount_opt, MINIX_DF); 468 break; 469 case Opt_grpid: 470 set_opt (sbi->s_mount_opt, GRPID); 471 break; 472 case Opt_nogrpid: 473 clear_opt (sbi->s_mount_opt, GRPID); 474 break; 475 case Opt_resuid: 476 if (match_int(&args[0], &option)) 477 return 0; 478 uid = make_kuid(current_user_ns(), option); 479 if (!uid_valid(uid)) { 480 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option); 481 return 0; 482 483 } 484 sbi->s_resuid = uid; 485 break; 486 case Opt_resgid: 487 if (match_int(&args[0], &option)) 488 return 0; 489 gid = make_kgid(current_user_ns(), option); 490 if (!gid_valid(gid)) { 491 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option); 492 return 0; 493 } 494 sbi->s_resgid = gid; 495 break; 496 case Opt_sb: 497 /* handled by get_sb_block() instead of here */ 498 /* *sb_block = match_int(&args[0]); */ 499 break; 500 case Opt_err_panic: 501 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 502 clear_opt (sbi->s_mount_opt, ERRORS_RO); 503 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 504 break; 505 case Opt_err_ro: 506 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 507 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 508 set_opt (sbi->s_mount_opt, ERRORS_RO); 509 break; 510 case Opt_err_cont: 511 clear_opt (sbi->s_mount_opt, ERRORS_RO); 512 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 513 set_opt (sbi->s_mount_opt, ERRORS_CONT); 514 break; 515 case Opt_nouid32: 516 set_opt (sbi->s_mount_opt, NO_UID32); 517 break; 518 case Opt_nocheck: 519 clear_opt (sbi->s_mount_opt, CHECK); 520 break; 521 case Opt_debug: 522 set_opt (sbi->s_mount_opt, DEBUG); 523 break; 524 case Opt_oldalloc: 525 set_opt (sbi->s_mount_opt, OLDALLOC); 526 break; 527 case Opt_orlov: 528 clear_opt (sbi->s_mount_opt, OLDALLOC); 529 break; 530 case Opt_nobh: 531 set_opt (sbi->s_mount_opt, NOBH); 532 break; 533 #ifdef CONFIG_EXT2_FS_XATTR 534 case Opt_user_xattr: 535 set_opt (sbi->s_mount_opt, XATTR_USER); 536 break; 537 case Opt_nouser_xattr: 538 clear_opt (sbi->s_mount_opt, XATTR_USER); 539 break; 540 #else 541 case Opt_user_xattr: 542 case Opt_nouser_xattr: 543 ext2_msg(sb, KERN_INFO, "(no)user_xattr options" 544 "not supported"); 545 break; 546 #endif 547 #ifdef CONFIG_EXT2_FS_POSIX_ACL 548 case Opt_acl: 549 set_opt(sbi->s_mount_opt, POSIX_ACL); 550 break; 551 case Opt_noacl: 552 clear_opt(sbi->s_mount_opt, POSIX_ACL); 553 break; 554 #else 555 case Opt_acl: 556 case Opt_noacl: 557 ext2_msg(sb, KERN_INFO, 558 "(no)acl options not supported"); 559 break; 560 #endif 561 case Opt_xip: 562 #ifdef CONFIG_EXT2_FS_XIP 563 set_opt (sbi->s_mount_opt, XIP); 564 #else 565 ext2_msg(sb, KERN_INFO, "xip option not supported"); 566 #endif 567 break; 568 569 #if defined(CONFIG_QUOTA) 570 case Opt_quota: 571 case Opt_usrquota: 572 set_opt(sbi->s_mount_opt, USRQUOTA); 573 break; 574 575 case Opt_grpquota: 576 set_opt(sbi->s_mount_opt, GRPQUOTA); 577 break; 578 #else 579 case Opt_quota: 580 case Opt_usrquota: 581 case Opt_grpquota: 582 ext2_msg(sb, KERN_INFO, 583 "quota operations not supported"); 584 break; 585 #endif 586 587 case Opt_reservation: 588 set_opt(sbi->s_mount_opt, RESERVATION); 589 ext2_msg(sb, KERN_INFO, "reservations ON"); 590 break; 591 case Opt_noreservation: 592 clear_opt(sbi->s_mount_opt, RESERVATION); 593 ext2_msg(sb, KERN_INFO, "reservations OFF"); 594 break; 595 case Opt_ignore: 596 break; 597 default: 598 return 0; 599 } 600 } 601 return 1; 602 } 603 604 static int ext2_setup_super (struct super_block * sb, 605 struct ext2_super_block * es, 606 int read_only) 607 { 608 int res = 0; 609 struct ext2_sb_info *sbi = EXT2_SB(sb); 610 611 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 612 ext2_msg(sb, KERN_ERR, 613 "error: revision level too high, " 614 "forcing read-only mode"); 615 res = MS_RDONLY; 616 } 617 if (read_only) 618 return res; 619 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 620 ext2_msg(sb, KERN_WARNING, 621 "warning: mounting unchecked fs, " 622 "running e2fsck is recommended"); 623 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 624 ext2_msg(sb, KERN_WARNING, 625 "warning: mounting fs with errors, " 626 "running e2fsck is recommended"); 627 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 628 le16_to_cpu(es->s_mnt_count) >= 629 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 630 ext2_msg(sb, KERN_WARNING, 631 "warning: maximal mount count reached, " 632 "running e2fsck is recommended"); 633 else if (le32_to_cpu(es->s_checkinterval) && 634 (le32_to_cpu(es->s_lastcheck) + 635 le32_to_cpu(es->s_checkinterval) <= get_seconds())) 636 ext2_msg(sb, KERN_WARNING, 637 "warning: checktime reached, " 638 "running e2fsck is recommended"); 639 if (!le16_to_cpu(es->s_max_mnt_count)) 640 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 641 le16_add_cpu(&es->s_mnt_count, 1); 642 if (test_opt (sb, DEBUG)) 643 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, " 644 "bpg=%lu, ipg=%lu, mo=%04lx]", 645 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 646 sbi->s_frag_size, 647 sbi->s_groups_count, 648 EXT2_BLOCKS_PER_GROUP(sb), 649 EXT2_INODES_PER_GROUP(sb), 650 sbi->s_mount_opt); 651 return res; 652 } 653 654 static int ext2_check_descriptors(struct super_block *sb) 655 { 656 int i; 657 struct ext2_sb_info *sbi = EXT2_SB(sb); 658 659 ext2_debug ("Checking group descriptors"); 660 661 for (i = 0; i < sbi->s_groups_count; i++) { 662 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 663 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 664 ext2_fsblk_t last_block; 665 666 if (i == sbi->s_groups_count - 1) 667 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 668 else 669 last_block = first_block + 670 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 671 672 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 673 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 674 { 675 ext2_error (sb, "ext2_check_descriptors", 676 "Block bitmap for group %d" 677 " not in group (block %lu)!", 678 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 679 return 0; 680 } 681 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 682 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 683 { 684 ext2_error (sb, "ext2_check_descriptors", 685 "Inode bitmap for group %d" 686 " not in group (block %lu)!", 687 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 688 return 0; 689 } 690 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 691 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 692 last_block) 693 { 694 ext2_error (sb, "ext2_check_descriptors", 695 "Inode table for group %d" 696 " not in group (block %lu)!", 697 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 698 return 0; 699 } 700 } 701 return 1; 702 } 703 704 /* 705 * Maximal file size. There is a direct, and {,double-,triple-}indirect 706 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 707 * We need to be 1 filesystem block less than the 2^32 sector limit. 708 */ 709 static loff_t ext2_max_size(int bits) 710 { 711 loff_t res = EXT2_NDIR_BLOCKS; 712 int meta_blocks; 713 loff_t upper_limit; 714 715 /* This is calculated to be the largest file size for a 716 * dense, file such that the total number of 717 * sectors in the file, including data and all indirect blocks, 718 * does not exceed 2^32 -1 719 * __u32 i_blocks representing the total number of 720 * 512 bytes blocks of the file 721 */ 722 upper_limit = (1LL << 32) - 1; 723 724 /* total blocks in file system block size */ 725 upper_limit >>= (bits - 9); 726 727 728 /* indirect blocks */ 729 meta_blocks = 1; 730 /* double indirect blocks */ 731 meta_blocks += 1 + (1LL << (bits-2)); 732 /* tripple indirect blocks */ 733 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2))); 734 735 upper_limit -= meta_blocks; 736 upper_limit <<= bits; 737 738 res += 1LL << (bits-2); 739 res += 1LL << (2*(bits-2)); 740 res += 1LL << (3*(bits-2)); 741 res <<= bits; 742 if (res > upper_limit) 743 res = upper_limit; 744 745 if (res > MAX_LFS_FILESIZE) 746 res = MAX_LFS_FILESIZE; 747 748 return res; 749 } 750 751 static unsigned long descriptor_loc(struct super_block *sb, 752 unsigned long logic_sb_block, 753 int nr) 754 { 755 struct ext2_sb_info *sbi = EXT2_SB(sb); 756 unsigned long bg, first_meta_bg; 757 int has_super = 0; 758 759 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 760 761 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 762 nr < first_meta_bg) 763 return (logic_sb_block + nr + 1); 764 bg = sbi->s_desc_per_block * nr; 765 if (ext2_bg_has_super(sb, bg)) 766 has_super = 1; 767 768 return ext2_group_first_block_no(sb, bg) + has_super; 769 } 770 771 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 772 { 773 struct buffer_head * bh; 774 struct ext2_sb_info * sbi; 775 struct ext2_super_block * es; 776 struct inode *root; 777 unsigned long block; 778 unsigned long sb_block = get_sb_block(&data); 779 unsigned long logic_sb_block; 780 unsigned long offset = 0; 781 unsigned long def_mount_opts; 782 long ret = -EINVAL; 783 int blocksize = BLOCK_SIZE; 784 int db_count; 785 int i, j; 786 __le32 features; 787 int err; 788 789 err = -ENOMEM; 790 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 791 if (!sbi) 792 goto failed; 793 794 sbi->s_blockgroup_lock = 795 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 796 if (!sbi->s_blockgroup_lock) { 797 kfree(sbi); 798 goto failed; 799 } 800 sb->s_fs_info = sbi; 801 sbi->s_sb_block = sb_block; 802 803 spin_lock_init(&sbi->s_lock); 804 805 /* 806 * See what the current blocksize for the device is, and 807 * use that as the blocksize. Otherwise (or if the blocksize 808 * is smaller than the default) use the default. 809 * This is important for devices that have a hardware 810 * sectorsize that is larger than the default. 811 */ 812 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 813 if (!blocksize) { 814 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 815 goto failed_sbi; 816 } 817 818 /* 819 * If the superblock doesn't start on a hardware sector boundary, 820 * calculate the offset. 821 */ 822 if (blocksize != BLOCK_SIZE) { 823 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 824 offset = (sb_block*BLOCK_SIZE) % blocksize; 825 } else { 826 logic_sb_block = sb_block; 827 } 828 829 if (!(bh = sb_bread(sb, logic_sb_block))) { 830 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 831 goto failed_sbi; 832 } 833 /* 834 * Note: s_es must be initialized as soon as possible because 835 * some ext2 macro-instructions depend on its value 836 */ 837 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 838 sbi->s_es = es; 839 sb->s_magic = le16_to_cpu(es->s_magic); 840 841 if (sb->s_magic != EXT2_SUPER_MAGIC) 842 goto cantfind_ext2; 843 844 /* Set defaults before we parse the mount options */ 845 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 846 if (def_mount_opts & EXT2_DEFM_DEBUG) 847 set_opt(sbi->s_mount_opt, DEBUG); 848 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 849 set_opt(sbi->s_mount_opt, GRPID); 850 if (def_mount_opts & EXT2_DEFM_UID16) 851 set_opt(sbi->s_mount_opt, NO_UID32); 852 #ifdef CONFIG_EXT2_FS_XATTR 853 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 854 set_opt(sbi->s_mount_opt, XATTR_USER); 855 #endif 856 #ifdef CONFIG_EXT2_FS_POSIX_ACL 857 if (def_mount_opts & EXT2_DEFM_ACL) 858 set_opt(sbi->s_mount_opt, POSIX_ACL); 859 #endif 860 861 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 862 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 863 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 864 set_opt(sbi->s_mount_opt, ERRORS_CONT); 865 else 866 set_opt(sbi->s_mount_opt, ERRORS_RO); 867 868 sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid)); 869 sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid)); 870 871 set_opt(sbi->s_mount_opt, RESERVATION); 872 873 if (!parse_options((char *) data, sb)) 874 goto failed_mount; 875 876 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 877 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 878 MS_POSIXACL : 0); 879 880 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 881 EXT2_MOUNT_XIP if not */ 882 883 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 884 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 885 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 886 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 887 ext2_msg(sb, KERN_WARNING, 888 "warning: feature flags set on rev 0 fs, " 889 "running e2fsck is recommended"); 890 /* 891 * Check feature flags regardless of the revision level, since we 892 * previously didn't change the revision level when setting the flags, 893 * so there is a chance incompat flags are set on a rev 0 filesystem. 894 */ 895 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 896 if (features) { 897 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 898 "unsupported optional features (%x)", 899 le32_to_cpu(features)); 900 goto failed_mount; 901 } 902 if (!(sb->s_flags & MS_RDONLY) && 903 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 904 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 905 "unsupported optional features (%x)", 906 le32_to_cpu(features)); 907 goto failed_mount; 908 } 909 910 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 911 912 if (ext2_use_xip(sb) && blocksize != PAGE_SIZE) { 913 if (!silent) 914 ext2_msg(sb, KERN_ERR, 915 "error: unsupported blocksize for xip"); 916 goto failed_mount; 917 } 918 919 /* If the blocksize doesn't match, re-read the thing.. */ 920 if (sb->s_blocksize != blocksize) { 921 brelse(bh); 922 923 if (!sb_set_blocksize(sb, blocksize)) { 924 ext2_msg(sb, KERN_ERR, 925 "error: bad blocksize %d", blocksize); 926 goto failed_sbi; 927 } 928 929 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 930 offset = (sb_block*BLOCK_SIZE) % blocksize; 931 bh = sb_bread(sb, logic_sb_block); 932 if(!bh) { 933 ext2_msg(sb, KERN_ERR, "error: couldn't read" 934 "superblock on 2nd try"); 935 goto failed_sbi; 936 } 937 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 938 sbi->s_es = es; 939 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 940 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 941 goto failed_mount; 942 } 943 } 944 945 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 946 sb->s_max_links = EXT2_LINK_MAX; 947 948 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 949 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 950 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 951 } else { 952 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 953 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 954 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 955 !is_power_of_2(sbi->s_inode_size) || 956 (sbi->s_inode_size > blocksize)) { 957 ext2_msg(sb, KERN_ERR, 958 "error: unsupported inode size: %d", 959 sbi->s_inode_size); 960 goto failed_mount; 961 } 962 } 963 964 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 965 le32_to_cpu(es->s_log_frag_size); 966 if (sbi->s_frag_size == 0) 967 goto cantfind_ext2; 968 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 969 970 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 971 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 972 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 973 974 if (EXT2_INODE_SIZE(sb) == 0) 975 goto cantfind_ext2; 976 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 977 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 978 goto cantfind_ext2; 979 sbi->s_itb_per_group = sbi->s_inodes_per_group / 980 sbi->s_inodes_per_block; 981 sbi->s_desc_per_block = sb->s_blocksize / 982 sizeof (struct ext2_group_desc); 983 sbi->s_sbh = bh; 984 sbi->s_mount_state = le16_to_cpu(es->s_state); 985 sbi->s_addr_per_block_bits = 986 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 987 sbi->s_desc_per_block_bits = 988 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 989 990 if (sb->s_magic != EXT2_SUPER_MAGIC) 991 goto cantfind_ext2; 992 993 if (sb->s_blocksize != bh->b_size) { 994 if (!silent) 995 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 996 goto failed_mount; 997 } 998 999 if (sb->s_blocksize != sbi->s_frag_size) { 1000 ext2_msg(sb, KERN_ERR, 1001 "error: fragsize %lu != blocksize %lu" 1002 "(not supported yet)", 1003 sbi->s_frag_size, sb->s_blocksize); 1004 goto failed_mount; 1005 } 1006 1007 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 1008 ext2_msg(sb, KERN_ERR, 1009 "error: #blocks per group too big: %lu", 1010 sbi->s_blocks_per_group); 1011 goto failed_mount; 1012 } 1013 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 1014 ext2_msg(sb, KERN_ERR, 1015 "error: #fragments per group too big: %lu", 1016 sbi->s_frags_per_group); 1017 goto failed_mount; 1018 } 1019 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 1020 ext2_msg(sb, KERN_ERR, 1021 "error: #inodes per group too big: %lu", 1022 sbi->s_inodes_per_group); 1023 goto failed_mount; 1024 } 1025 1026 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 1027 goto cantfind_ext2; 1028 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1029 le32_to_cpu(es->s_first_data_block) - 1) 1030 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1031 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1032 EXT2_DESC_PER_BLOCK(sb); 1033 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 1034 if (sbi->s_group_desc == NULL) { 1035 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1036 goto failed_mount; 1037 } 1038 bgl_lock_init(sbi->s_blockgroup_lock); 1039 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1040 if (!sbi->s_debts) { 1041 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1042 goto failed_mount_group_desc; 1043 } 1044 for (i = 0; i < db_count; i++) { 1045 block = descriptor_loc(sb, logic_sb_block, i); 1046 sbi->s_group_desc[i] = sb_bread(sb, block); 1047 if (!sbi->s_group_desc[i]) { 1048 for (j = 0; j < i; j++) 1049 brelse (sbi->s_group_desc[j]); 1050 ext2_msg(sb, KERN_ERR, 1051 "error: unable to read group descriptors"); 1052 goto failed_mount_group_desc; 1053 } 1054 } 1055 if (!ext2_check_descriptors (sb)) { 1056 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1057 goto failed_mount2; 1058 } 1059 sbi->s_gdb_count = db_count; 1060 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1061 spin_lock_init(&sbi->s_next_gen_lock); 1062 1063 /* per fileystem reservation list head & lock */ 1064 spin_lock_init(&sbi->s_rsv_window_lock); 1065 sbi->s_rsv_window_root = RB_ROOT; 1066 /* 1067 * Add a single, static dummy reservation to the start of the 1068 * reservation window list --- it gives us a placeholder for 1069 * append-at-start-of-list which makes the allocation logic 1070 * _much_ simpler. 1071 */ 1072 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1073 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1074 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1075 sbi->s_rsv_window_head.rsv_goal_size = 0; 1076 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1077 1078 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1079 ext2_count_free_blocks(sb), GFP_KERNEL); 1080 if (!err) { 1081 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1082 ext2_count_free_inodes(sb), GFP_KERNEL); 1083 } 1084 if (!err) { 1085 err = percpu_counter_init(&sbi->s_dirs_counter, 1086 ext2_count_dirs(sb), GFP_KERNEL); 1087 } 1088 if (err) { 1089 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1090 goto failed_mount3; 1091 } 1092 /* 1093 * set up enough so that it can read an inode 1094 */ 1095 sb->s_op = &ext2_sops; 1096 sb->s_export_op = &ext2_export_ops; 1097 sb->s_xattr = ext2_xattr_handlers; 1098 1099 #ifdef CONFIG_QUOTA 1100 sb->dq_op = &dquot_operations; 1101 sb->s_qcop = &dquot_quotactl_ops; 1102 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP; 1103 #endif 1104 1105 root = ext2_iget(sb, EXT2_ROOT_INO); 1106 if (IS_ERR(root)) { 1107 ret = PTR_ERR(root); 1108 goto failed_mount3; 1109 } 1110 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1111 iput(root); 1112 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1113 goto failed_mount3; 1114 } 1115 1116 sb->s_root = d_make_root(root); 1117 if (!sb->s_root) { 1118 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1119 ret = -ENOMEM; 1120 goto failed_mount3; 1121 } 1122 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1123 ext2_msg(sb, KERN_WARNING, 1124 "warning: mounting ext3 filesystem as ext2"); 1125 if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY)) 1126 sb->s_flags |= MS_RDONLY; 1127 ext2_write_super(sb); 1128 return 0; 1129 1130 cantfind_ext2: 1131 if (!silent) 1132 ext2_msg(sb, KERN_ERR, 1133 "error: can't find an ext2 filesystem on dev %s.", 1134 sb->s_id); 1135 goto failed_mount; 1136 failed_mount3: 1137 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1138 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1139 percpu_counter_destroy(&sbi->s_dirs_counter); 1140 failed_mount2: 1141 for (i = 0; i < db_count; i++) 1142 brelse(sbi->s_group_desc[i]); 1143 failed_mount_group_desc: 1144 kfree(sbi->s_group_desc); 1145 kfree(sbi->s_debts); 1146 failed_mount: 1147 brelse(bh); 1148 failed_sbi: 1149 sb->s_fs_info = NULL; 1150 kfree(sbi->s_blockgroup_lock); 1151 kfree(sbi); 1152 failed: 1153 return ret; 1154 } 1155 1156 static void ext2_clear_super_error(struct super_block *sb) 1157 { 1158 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1159 1160 if (buffer_write_io_error(sbh)) { 1161 /* 1162 * Oh, dear. A previous attempt to write the 1163 * superblock failed. This could happen because the 1164 * USB device was yanked out. Or it could happen to 1165 * be a transient write error and maybe the block will 1166 * be remapped. Nothing we can do but to retry the 1167 * write and hope for the best. 1168 */ 1169 ext2_msg(sb, KERN_ERR, 1170 "previous I/O error to superblock detected\n"); 1171 clear_buffer_write_io_error(sbh); 1172 set_buffer_uptodate(sbh); 1173 } 1174 } 1175 1176 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, 1177 int wait) 1178 { 1179 ext2_clear_super_error(sb); 1180 spin_lock(&EXT2_SB(sb)->s_lock); 1181 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1182 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1183 es->s_wtime = cpu_to_le32(get_seconds()); 1184 /* unlock before we do IO */ 1185 spin_unlock(&EXT2_SB(sb)->s_lock); 1186 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1187 if (wait) 1188 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1189 } 1190 1191 /* 1192 * In the second extended file system, it is not necessary to 1193 * write the super block since we use a mapping of the 1194 * disk super block in a buffer. 1195 * 1196 * However, this function is still used to set the fs valid 1197 * flags to 0. We need to set this flag to 0 since the fs 1198 * may have been checked while mounted and e2fsck may have 1199 * set s_state to EXT2_VALID_FS after some corrections. 1200 */ 1201 static int ext2_sync_fs(struct super_block *sb, int wait) 1202 { 1203 struct ext2_sb_info *sbi = EXT2_SB(sb); 1204 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1205 1206 /* 1207 * Write quota structures to quota file, sync_blockdev() will write 1208 * them to disk later 1209 */ 1210 dquot_writeback_dquots(sb, -1); 1211 1212 spin_lock(&sbi->s_lock); 1213 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1214 ext2_debug("setting valid to 0\n"); 1215 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1216 } 1217 spin_unlock(&sbi->s_lock); 1218 ext2_sync_super(sb, es, wait); 1219 return 0; 1220 } 1221 1222 static int ext2_freeze(struct super_block *sb) 1223 { 1224 struct ext2_sb_info *sbi = EXT2_SB(sb); 1225 1226 /* 1227 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared 1228 * because we have unattached inodes and thus filesystem is not fully 1229 * consistent. 1230 */ 1231 if (atomic_long_read(&sb->s_remove_count)) { 1232 ext2_sync_fs(sb, 1); 1233 return 0; 1234 } 1235 /* Set EXT2_FS_VALID flag */ 1236 spin_lock(&sbi->s_lock); 1237 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); 1238 spin_unlock(&sbi->s_lock); 1239 ext2_sync_super(sb, sbi->s_es, 1); 1240 1241 return 0; 1242 } 1243 1244 static int ext2_unfreeze(struct super_block *sb) 1245 { 1246 /* Just write sb to clear EXT2_VALID_FS flag */ 1247 ext2_write_super(sb); 1248 1249 return 0; 1250 } 1251 1252 void ext2_write_super(struct super_block *sb) 1253 { 1254 if (!(sb->s_flags & MS_RDONLY)) 1255 ext2_sync_fs(sb, 1); 1256 } 1257 1258 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1259 { 1260 struct ext2_sb_info * sbi = EXT2_SB(sb); 1261 struct ext2_super_block * es; 1262 unsigned long old_mount_opt = sbi->s_mount_opt; 1263 struct ext2_mount_options old_opts; 1264 unsigned long old_sb_flags; 1265 int err; 1266 1267 sync_filesystem(sb); 1268 spin_lock(&sbi->s_lock); 1269 1270 /* Store the old options */ 1271 old_sb_flags = sb->s_flags; 1272 old_opts.s_mount_opt = sbi->s_mount_opt; 1273 old_opts.s_resuid = sbi->s_resuid; 1274 old_opts.s_resgid = sbi->s_resgid; 1275 1276 /* 1277 * Allow the "check" option to be passed as a remount option. 1278 */ 1279 if (!parse_options(data, sb)) { 1280 err = -EINVAL; 1281 goto restore_opts; 1282 } 1283 1284 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1285 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1286 1287 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 1288 EXT2_MOUNT_XIP if not */ 1289 1290 if ((ext2_use_xip(sb)) && (sb->s_blocksize != PAGE_SIZE)) { 1291 ext2_msg(sb, KERN_WARNING, 1292 "warning: unsupported blocksize for xip"); 1293 err = -EINVAL; 1294 goto restore_opts; 1295 } 1296 1297 es = sbi->s_es; 1298 if ((sbi->s_mount_opt ^ old_mount_opt) & EXT2_MOUNT_XIP) { 1299 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1300 "xip flag with busy inodes while remounting"); 1301 sbi->s_mount_opt &= ~EXT2_MOUNT_XIP; 1302 sbi->s_mount_opt |= old_mount_opt & EXT2_MOUNT_XIP; 1303 } 1304 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { 1305 spin_unlock(&sbi->s_lock); 1306 return 0; 1307 } 1308 if (*flags & MS_RDONLY) { 1309 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1310 !(sbi->s_mount_state & EXT2_VALID_FS)) { 1311 spin_unlock(&sbi->s_lock); 1312 return 0; 1313 } 1314 1315 /* 1316 * OK, we are remounting a valid rw partition rdonly, so set 1317 * the rdonly flag and then mark the partition as valid again. 1318 */ 1319 es->s_state = cpu_to_le16(sbi->s_mount_state); 1320 es->s_mtime = cpu_to_le32(get_seconds()); 1321 spin_unlock(&sbi->s_lock); 1322 1323 err = dquot_suspend(sb, -1); 1324 if (err < 0) { 1325 spin_lock(&sbi->s_lock); 1326 goto restore_opts; 1327 } 1328 1329 ext2_sync_super(sb, es, 1); 1330 } else { 1331 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1332 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1333 if (ret) { 1334 ext2_msg(sb, KERN_WARNING, 1335 "warning: couldn't remount RDWR because of " 1336 "unsupported optional features (%x).", 1337 le32_to_cpu(ret)); 1338 err = -EROFS; 1339 goto restore_opts; 1340 } 1341 /* 1342 * Mounting a RDONLY partition read-write, so reread and 1343 * store the current valid flag. (It may have been changed 1344 * by e2fsck since we originally mounted the partition.) 1345 */ 1346 sbi->s_mount_state = le16_to_cpu(es->s_state); 1347 if (!ext2_setup_super (sb, es, 0)) 1348 sb->s_flags &= ~MS_RDONLY; 1349 spin_unlock(&sbi->s_lock); 1350 1351 ext2_write_super(sb); 1352 1353 dquot_resume(sb, -1); 1354 } 1355 1356 return 0; 1357 restore_opts: 1358 sbi->s_mount_opt = old_opts.s_mount_opt; 1359 sbi->s_resuid = old_opts.s_resuid; 1360 sbi->s_resgid = old_opts.s_resgid; 1361 sb->s_flags = old_sb_flags; 1362 spin_unlock(&sbi->s_lock); 1363 return err; 1364 } 1365 1366 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1367 { 1368 struct super_block *sb = dentry->d_sb; 1369 struct ext2_sb_info *sbi = EXT2_SB(sb); 1370 struct ext2_super_block *es = sbi->s_es; 1371 u64 fsid; 1372 1373 spin_lock(&sbi->s_lock); 1374 1375 if (test_opt (sb, MINIX_DF)) 1376 sbi->s_overhead_last = 0; 1377 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1378 unsigned long i, overhead = 0; 1379 smp_rmb(); 1380 1381 /* 1382 * Compute the overhead (FS structures). This is constant 1383 * for a given filesystem unless the number of block groups 1384 * changes so we cache the previous value until it does. 1385 */ 1386 1387 /* 1388 * All of the blocks before first_data_block are 1389 * overhead 1390 */ 1391 overhead = le32_to_cpu(es->s_first_data_block); 1392 1393 /* 1394 * Add the overhead attributed to the superblock and 1395 * block group descriptors. If the sparse superblocks 1396 * feature is turned on, then not all groups have this. 1397 */ 1398 for (i = 0; i < sbi->s_groups_count; i++) 1399 overhead += ext2_bg_has_super(sb, i) + 1400 ext2_bg_num_gdb(sb, i); 1401 1402 /* 1403 * Every block group has an inode bitmap, a block 1404 * bitmap, and an inode table. 1405 */ 1406 overhead += (sbi->s_groups_count * 1407 (2 + sbi->s_itb_per_group)); 1408 sbi->s_overhead_last = overhead; 1409 smp_wmb(); 1410 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1411 } 1412 1413 buf->f_type = EXT2_SUPER_MAGIC; 1414 buf->f_bsize = sb->s_blocksize; 1415 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1416 buf->f_bfree = ext2_count_free_blocks(sb); 1417 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1418 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1419 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1420 buf->f_bavail = 0; 1421 buf->f_files = le32_to_cpu(es->s_inodes_count); 1422 buf->f_ffree = ext2_count_free_inodes(sb); 1423 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1424 buf->f_namelen = EXT2_NAME_LEN; 1425 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1426 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1427 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1428 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1429 spin_unlock(&sbi->s_lock); 1430 return 0; 1431 } 1432 1433 static struct dentry *ext2_mount(struct file_system_type *fs_type, 1434 int flags, const char *dev_name, void *data) 1435 { 1436 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1437 } 1438 1439 #ifdef CONFIG_QUOTA 1440 1441 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1442 * acquiring the locks... As quota files are never truncated and quota code 1443 * itself serializes the operations (and no one else should touch the files) 1444 * we don't have to be afraid of races */ 1445 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1446 size_t len, loff_t off) 1447 { 1448 struct inode *inode = sb_dqopt(sb)->files[type]; 1449 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1450 int err = 0; 1451 int offset = off & (sb->s_blocksize - 1); 1452 int tocopy; 1453 size_t toread; 1454 struct buffer_head tmp_bh; 1455 struct buffer_head *bh; 1456 loff_t i_size = i_size_read(inode); 1457 1458 if (off > i_size) 1459 return 0; 1460 if (off+len > i_size) 1461 len = i_size-off; 1462 toread = len; 1463 while (toread > 0) { 1464 tocopy = sb->s_blocksize - offset < toread ? 1465 sb->s_blocksize - offset : toread; 1466 1467 tmp_bh.b_state = 0; 1468 tmp_bh.b_size = sb->s_blocksize; 1469 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1470 if (err < 0) 1471 return err; 1472 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1473 memset(data, 0, tocopy); 1474 else { 1475 bh = sb_bread(sb, tmp_bh.b_blocknr); 1476 if (!bh) 1477 return -EIO; 1478 memcpy(data, bh->b_data+offset, tocopy); 1479 brelse(bh); 1480 } 1481 offset = 0; 1482 toread -= tocopy; 1483 data += tocopy; 1484 blk++; 1485 } 1486 return len; 1487 } 1488 1489 /* Write to quotafile */ 1490 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1491 const char *data, size_t len, loff_t off) 1492 { 1493 struct inode *inode = sb_dqopt(sb)->files[type]; 1494 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1495 int err = 0; 1496 int offset = off & (sb->s_blocksize - 1); 1497 int tocopy; 1498 size_t towrite = len; 1499 struct buffer_head tmp_bh; 1500 struct buffer_head *bh; 1501 1502 while (towrite > 0) { 1503 tocopy = sb->s_blocksize - offset < towrite ? 1504 sb->s_blocksize - offset : towrite; 1505 1506 tmp_bh.b_state = 0; 1507 tmp_bh.b_size = sb->s_blocksize; 1508 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1509 if (err < 0) 1510 goto out; 1511 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1512 bh = sb_bread(sb, tmp_bh.b_blocknr); 1513 else 1514 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1515 if (unlikely(!bh)) { 1516 err = -EIO; 1517 goto out; 1518 } 1519 lock_buffer(bh); 1520 memcpy(bh->b_data+offset, data, tocopy); 1521 flush_dcache_page(bh->b_page); 1522 set_buffer_uptodate(bh); 1523 mark_buffer_dirty(bh); 1524 unlock_buffer(bh); 1525 brelse(bh); 1526 offset = 0; 1527 towrite -= tocopy; 1528 data += tocopy; 1529 blk++; 1530 } 1531 out: 1532 if (len == towrite) 1533 return err; 1534 if (inode->i_size < off+len-towrite) 1535 i_size_write(inode, off+len-towrite); 1536 inode->i_version++; 1537 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1538 mark_inode_dirty(inode); 1539 return len - towrite; 1540 } 1541 1542 #endif 1543 1544 static struct file_system_type ext2_fs_type = { 1545 .owner = THIS_MODULE, 1546 .name = "ext2", 1547 .mount = ext2_mount, 1548 .kill_sb = kill_block_super, 1549 .fs_flags = FS_REQUIRES_DEV, 1550 }; 1551 MODULE_ALIAS_FS("ext2"); 1552 1553 static int __init init_ext2_fs(void) 1554 { 1555 int err = init_ext2_xattr(); 1556 if (err) 1557 return err; 1558 err = init_inodecache(); 1559 if (err) 1560 goto out1; 1561 err = register_filesystem(&ext2_fs_type); 1562 if (err) 1563 goto out; 1564 return 0; 1565 out: 1566 destroy_inodecache(); 1567 out1: 1568 exit_ext2_xattr(); 1569 return err; 1570 } 1571 1572 static void __exit exit_ext2_fs(void) 1573 { 1574 unregister_filesystem(&ext2_fs_type); 1575 destroy_inodecache(); 1576 exit_ext2_xattr(); 1577 } 1578 1579 MODULE_AUTHOR("Remy Card and others"); 1580 MODULE_DESCRIPTION("Second Extended Filesystem"); 1581 MODULE_LICENSE("GPL"); 1582 module_init(init_ext2_fs) 1583 module_exit(exit_ext2_fs) 1584