1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/fs/ext2/super.c 4 * 5 * Copyright (C) 1992, 1993, 1994, 1995 6 * Remy Card (card@masi.ibp.fr) 7 * Laboratoire MASI - Institut Blaise Pascal 8 * Universite Pierre et Marie Curie (Paris VI) 9 * 10 * from 11 * 12 * linux/fs/minix/inode.c 13 * 14 * Copyright (C) 1991, 1992 Linus Torvalds 15 * 16 * Big-endian to little-endian byte-swapping/bitmaps by 17 * David S. Miller (davem@caip.rutgers.edu), 1995 18 */ 19 20 #include <linux/module.h> 21 #include <linux/string.h> 22 #include <linux/fs.h> 23 #include <linux/slab.h> 24 #include <linux/init.h> 25 #include <linux/blkdev.h> 26 #include <linux/parser.h> 27 #include <linux/random.h> 28 #include <linux/buffer_head.h> 29 #include <linux/exportfs.h> 30 #include <linux/vfs.h> 31 #include <linux/seq_file.h> 32 #include <linux/mount.h> 33 #include <linux/log2.h> 34 #include <linux/quotaops.h> 35 #include <linux/uaccess.h> 36 #include <linux/dax.h> 37 #include <linux/iversion.h> 38 #include "ext2.h" 39 #include "xattr.h" 40 #include "acl.h" 41 42 static void ext2_write_super(struct super_block *sb); 43 static int ext2_remount (struct super_block * sb, int * flags, char * data); 44 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf); 45 static int ext2_sync_fs(struct super_block *sb, int wait); 46 static int ext2_freeze(struct super_block *sb); 47 static int ext2_unfreeze(struct super_block *sb); 48 49 void ext2_error(struct super_block *sb, const char *function, 50 const char *fmt, ...) 51 { 52 struct va_format vaf; 53 va_list args; 54 struct ext2_sb_info *sbi = EXT2_SB(sb); 55 struct ext2_super_block *es = sbi->s_es; 56 57 if (!sb_rdonly(sb)) { 58 spin_lock(&sbi->s_lock); 59 sbi->s_mount_state |= EXT2_ERROR_FS; 60 es->s_state |= cpu_to_le16(EXT2_ERROR_FS); 61 spin_unlock(&sbi->s_lock); 62 ext2_sync_super(sb, es, 1); 63 } 64 65 va_start(args, fmt); 66 67 vaf.fmt = fmt; 68 vaf.va = &args; 69 70 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n", 71 sb->s_id, function, &vaf); 72 73 va_end(args); 74 75 if (test_opt(sb, ERRORS_PANIC)) 76 panic("EXT2-fs: panic from previous error\n"); 77 if (!sb_rdonly(sb) && test_opt(sb, ERRORS_RO)) { 78 ext2_msg(sb, KERN_CRIT, 79 "error: remounting filesystem read-only"); 80 sb->s_flags |= SB_RDONLY; 81 } 82 } 83 84 void ext2_msg(struct super_block *sb, const char *prefix, 85 const char *fmt, ...) 86 { 87 struct va_format vaf; 88 va_list args; 89 90 va_start(args, fmt); 91 92 vaf.fmt = fmt; 93 vaf.va = &args; 94 95 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf); 96 97 va_end(args); 98 } 99 100 /* 101 * This must be called with sbi->s_lock held. 102 */ 103 void ext2_update_dynamic_rev(struct super_block *sb) 104 { 105 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 106 107 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) 108 return; 109 110 ext2_msg(sb, KERN_WARNING, 111 "warning: updating to rev %d because of " 112 "new feature flag, running e2fsck is recommended", 113 EXT2_DYNAMIC_REV); 114 115 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); 116 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); 117 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); 118 /* leave es->s_feature_*compat flags alone */ 119 /* es->s_uuid will be set by e2fsck if empty */ 120 121 /* 122 * The rest of the superblock fields should be zero, and if not it 123 * means they are likely already in use, so leave them alone. We 124 * can leave it up to e2fsck to clean up any inconsistencies there. 125 */ 126 } 127 128 #ifdef CONFIG_QUOTA 129 static int ext2_quota_off(struct super_block *sb, int type); 130 131 static void ext2_quota_off_umount(struct super_block *sb) 132 { 133 int type; 134 135 for (type = 0; type < MAXQUOTAS; type++) 136 ext2_quota_off(sb, type); 137 } 138 #else 139 static inline void ext2_quota_off_umount(struct super_block *sb) 140 { 141 } 142 #endif 143 144 static void ext2_put_super (struct super_block * sb) 145 { 146 int db_count; 147 int i; 148 struct ext2_sb_info *sbi = EXT2_SB(sb); 149 150 ext2_quota_off_umount(sb); 151 152 ext2_xattr_destroy_cache(sbi->s_ea_block_cache); 153 sbi->s_ea_block_cache = NULL; 154 155 if (!sb_rdonly(sb)) { 156 struct ext2_super_block *es = sbi->s_es; 157 158 spin_lock(&sbi->s_lock); 159 es->s_state = cpu_to_le16(sbi->s_mount_state); 160 spin_unlock(&sbi->s_lock); 161 ext2_sync_super(sb, es, 1); 162 } 163 db_count = sbi->s_gdb_count; 164 for (i = 0; i < db_count; i++) 165 brelse(sbi->s_group_desc[i]); 166 kfree(sbi->s_group_desc); 167 kfree(sbi->s_debts); 168 percpu_counter_destroy(&sbi->s_freeblocks_counter); 169 percpu_counter_destroy(&sbi->s_freeinodes_counter); 170 percpu_counter_destroy(&sbi->s_dirs_counter); 171 brelse (sbi->s_sbh); 172 sb->s_fs_info = NULL; 173 kfree(sbi->s_blockgroup_lock); 174 fs_put_dax(sbi->s_daxdev); 175 kfree(sbi); 176 } 177 178 static struct kmem_cache * ext2_inode_cachep; 179 180 static struct inode *ext2_alloc_inode(struct super_block *sb) 181 { 182 struct ext2_inode_info *ei; 183 ei = alloc_inode_sb(sb, ext2_inode_cachep, GFP_KERNEL); 184 if (!ei) 185 return NULL; 186 ei->i_block_alloc_info = NULL; 187 inode_set_iversion(&ei->vfs_inode, 1); 188 #ifdef CONFIG_QUOTA 189 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot)); 190 #endif 191 192 return &ei->vfs_inode; 193 } 194 195 static void ext2_free_in_core_inode(struct inode *inode) 196 { 197 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 198 } 199 200 static void init_once(void *foo) 201 { 202 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 203 204 rwlock_init(&ei->i_meta_lock); 205 #ifdef CONFIG_EXT2_FS_XATTR 206 init_rwsem(&ei->xattr_sem); 207 #endif 208 mutex_init(&ei->truncate_mutex); 209 inode_init_once(&ei->vfs_inode); 210 } 211 212 static int __init init_inodecache(void) 213 { 214 ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache", 215 sizeof(struct ext2_inode_info), 0, 216 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD| 217 SLAB_ACCOUNT), 218 offsetof(struct ext2_inode_info, i_data), 219 sizeof_field(struct ext2_inode_info, i_data), 220 init_once); 221 if (ext2_inode_cachep == NULL) 222 return -ENOMEM; 223 return 0; 224 } 225 226 static void destroy_inodecache(void) 227 { 228 /* 229 * Make sure all delayed rcu free inodes are flushed before we 230 * destroy cache. 231 */ 232 rcu_barrier(); 233 kmem_cache_destroy(ext2_inode_cachep); 234 } 235 236 static int ext2_show_options(struct seq_file *seq, struct dentry *root) 237 { 238 struct super_block *sb = root->d_sb; 239 struct ext2_sb_info *sbi = EXT2_SB(sb); 240 struct ext2_super_block *es = sbi->s_es; 241 unsigned long def_mount_opts; 242 243 spin_lock(&sbi->s_lock); 244 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 245 246 if (sbi->s_sb_block != 1) 247 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 248 if (test_opt(sb, MINIX_DF)) 249 seq_puts(seq, ",minixdf"); 250 if (test_opt(sb, GRPID)) 251 seq_puts(seq, ",grpid"); 252 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 253 seq_puts(seq, ",nogrpid"); 254 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) || 255 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 256 seq_printf(seq, ",resuid=%u", 257 from_kuid_munged(&init_user_ns, sbi->s_resuid)); 258 } 259 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) || 260 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 261 seq_printf(seq, ",resgid=%u", 262 from_kgid_munged(&init_user_ns, sbi->s_resgid)); 263 } 264 if (test_opt(sb, ERRORS_RO)) { 265 int def_errors = le16_to_cpu(es->s_errors); 266 267 if (def_errors == EXT2_ERRORS_PANIC || 268 def_errors == EXT2_ERRORS_CONTINUE) { 269 seq_puts(seq, ",errors=remount-ro"); 270 } 271 } 272 if (test_opt(sb, ERRORS_CONT)) 273 seq_puts(seq, ",errors=continue"); 274 if (test_opt(sb, ERRORS_PANIC)) 275 seq_puts(seq, ",errors=panic"); 276 if (test_opt(sb, NO_UID32)) 277 seq_puts(seq, ",nouid32"); 278 if (test_opt(sb, DEBUG)) 279 seq_puts(seq, ",debug"); 280 if (test_opt(sb, OLDALLOC)) 281 seq_puts(seq, ",oldalloc"); 282 283 #ifdef CONFIG_EXT2_FS_XATTR 284 if (test_opt(sb, XATTR_USER)) 285 seq_puts(seq, ",user_xattr"); 286 if (!test_opt(sb, XATTR_USER) && 287 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 288 seq_puts(seq, ",nouser_xattr"); 289 } 290 #endif 291 292 #ifdef CONFIG_EXT2_FS_POSIX_ACL 293 if (test_opt(sb, POSIX_ACL)) 294 seq_puts(seq, ",acl"); 295 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 296 seq_puts(seq, ",noacl"); 297 #endif 298 299 if (test_opt(sb, NOBH)) 300 seq_puts(seq, ",nobh"); 301 302 if (test_opt(sb, USRQUOTA)) 303 seq_puts(seq, ",usrquota"); 304 305 if (test_opt(sb, GRPQUOTA)) 306 seq_puts(seq, ",grpquota"); 307 308 if (test_opt(sb, XIP)) 309 seq_puts(seq, ",xip"); 310 311 if (test_opt(sb, DAX)) 312 seq_puts(seq, ",dax"); 313 314 if (!test_opt(sb, RESERVATION)) 315 seq_puts(seq, ",noreservation"); 316 317 spin_unlock(&sbi->s_lock); 318 return 0; 319 } 320 321 #ifdef CONFIG_QUOTA 322 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 323 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 324 static int ext2_quota_on(struct super_block *sb, int type, int format_id, 325 const struct path *path); 326 static struct dquot **ext2_get_dquots(struct inode *inode) 327 { 328 return EXT2_I(inode)->i_dquot; 329 } 330 331 static const struct quotactl_ops ext2_quotactl_ops = { 332 .quota_on = ext2_quota_on, 333 .quota_off = ext2_quota_off, 334 .quota_sync = dquot_quota_sync, 335 .get_state = dquot_get_state, 336 .set_info = dquot_set_dqinfo, 337 .get_dqblk = dquot_get_dqblk, 338 .set_dqblk = dquot_set_dqblk, 339 .get_nextdqblk = dquot_get_next_dqblk, 340 }; 341 #endif 342 343 static const struct super_operations ext2_sops = { 344 .alloc_inode = ext2_alloc_inode, 345 .free_inode = ext2_free_in_core_inode, 346 .write_inode = ext2_write_inode, 347 .evict_inode = ext2_evict_inode, 348 .put_super = ext2_put_super, 349 .sync_fs = ext2_sync_fs, 350 .freeze_fs = ext2_freeze, 351 .unfreeze_fs = ext2_unfreeze, 352 .statfs = ext2_statfs, 353 .remount_fs = ext2_remount, 354 .show_options = ext2_show_options, 355 #ifdef CONFIG_QUOTA 356 .quota_read = ext2_quota_read, 357 .quota_write = ext2_quota_write, 358 .get_dquots = ext2_get_dquots, 359 #endif 360 }; 361 362 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 363 u64 ino, u32 generation) 364 { 365 struct inode *inode; 366 367 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 368 return ERR_PTR(-ESTALE); 369 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 370 return ERR_PTR(-ESTALE); 371 372 /* 373 * ext2_iget isn't quite right if the inode is currently unallocated! 374 * However ext2_iget currently does appropriate checks to handle stale 375 * inodes so everything is OK. 376 */ 377 inode = ext2_iget(sb, ino); 378 if (IS_ERR(inode)) 379 return ERR_CAST(inode); 380 if (generation && inode->i_generation != generation) { 381 /* we didn't find the right inode.. */ 382 iput(inode); 383 return ERR_PTR(-ESTALE); 384 } 385 return inode; 386 } 387 388 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 389 int fh_len, int fh_type) 390 { 391 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 392 ext2_nfs_get_inode); 393 } 394 395 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 396 int fh_len, int fh_type) 397 { 398 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 399 ext2_nfs_get_inode); 400 } 401 402 static const struct export_operations ext2_export_ops = { 403 .fh_to_dentry = ext2_fh_to_dentry, 404 .fh_to_parent = ext2_fh_to_parent, 405 .get_parent = ext2_get_parent, 406 }; 407 408 static unsigned long get_sb_block(void **data) 409 { 410 unsigned long sb_block; 411 char *options = (char *) *data; 412 413 if (!options || strncmp(options, "sb=", 3) != 0) 414 return 1; /* Default location */ 415 options += 3; 416 sb_block = simple_strtoul(options, &options, 0); 417 if (*options && *options != ',') { 418 printk("EXT2-fs: Invalid sb specification: %s\n", 419 (char *) *data); 420 return 1; 421 } 422 if (*options == ',') 423 options++; 424 *data = (void *) options; 425 return sb_block; 426 } 427 428 enum { 429 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 430 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 431 Opt_err_ro, Opt_nouid32, Opt_debug, 432 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 433 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota, 434 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 435 }; 436 437 static const match_table_t tokens = { 438 {Opt_bsd_df, "bsddf"}, 439 {Opt_minix_df, "minixdf"}, 440 {Opt_grpid, "grpid"}, 441 {Opt_grpid, "bsdgroups"}, 442 {Opt_nogrpid, "nogrpid"}, 443 {Opt_nogrpid, "sysvgroups"}, 444 {Opt_resgid, "resgid=%u"}, 445 {Opt_resuid, "resuid=%u"}, 446 {Opt_sb, "sb=%u"}, 447 {Opt_err_cont, "errors=continue"}, 448 {Opt_err_panic, "errors=panic"}, 449 {Opt_err_ro, "errors=remount-ro"}, 450 {Opt_nouid32, "nouid32"}, 451 {Opt_debug, "debug"}, 452 {Opt_oldalloc, "oldalloc"}, 453 {Opt_orlov, "orlov"}, 454 {Opt_nobh, "nobh"}, 455 {Opt_user_xattr, "user_xattr"}, 456 {Opt_nouser_xattr, "nouser_xattr"}, 457 {Opt_acl, "acl"}, 458 {Opt_noacl, "noacl"}, 459 {Opt_xip, "xip"}, 460 {Opt_dax, "dax"}, 461 {Opt_grpquota, "grpquota"}, 462 {Opt_ignore, "noquota"}, 463 {Opt_quota, "quota"}, 464 {Opt_usrquota, "usrquota"}, 465 {Opt_reservation, "reservation"}, 466 {Opt_noreservation, "noreservation"}, 467 {Opt_err, NULL} 468 }; 469 470 static int parse_options(char *options, struct super_block *sb, 471 struct ext2_mount_options *opts) 472 { 473 char *p; 474 substring_t args[MAX_OPT_ARGS]; 475 int option; 476 kuid_t uid; 477 kgid_t gid; 478 479 if (!options) 480 return 1; 481 482 while ((p = strsep (&options, ",")) != NULL) { 483 int token; 484 if (!*p) 485 continue; 486 487 token = match_token(p, tokens, args); 488 switch (token) { 489 case Opt_bsd_df: 490 clear_opt (opts->s_mount_opt, MINIX_DF); 491 break; 492 case Opt_minix_df: 493 set_opt (opts->s_mount_opt, MINIX_DF); 494 break; 495 case Opt_grpid: 496 set_opt (opts->s_mount_opt, GRPID); 497 break; 498 case Opt_nogrpid: 499 clear_opt (opts->s_mount_opt, GRPID); 500 break; 501 case Opt_resuid: 502 if (match_int(&args[0], &option)) 503 return 0; 504 uid = make_kuid(current_user_ns(), option); 505 if (!uid_valid(uid)) { 506 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option); 507 return 0; 508 509 } 510 opts->s_resuid = uid; 511 break; 512 case Opt_resgid: 513 if (match_int(&args[0], &option)) 514 return 0; 515 gid = make_kgid(current_user_ns(), option); 516 if (!gid_valid(gid)) { 517 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option); 518 return 0; 519 } 520 opts->s_resgid = gid; 521 break; 522 case Opt_sb: 523 /* handled by get_sb_block() instead of here */ 524 /* *sb_block = match_int(&args[0]); */ 525 break; 526 case Opt_err_panic: 527 clear_opt (opts->s_mount_opt, ERRORS_CONT); 528 clear_opt (opts->s_mount_opt, ERRORS_RO); 529 set_opt (opts->s_mount_opt, ERRORS_PANIC); 530 break; 531 case Opt_err_ro: 532 clear_opt (opts->s_mount_opt, ERRORS_CONT); 533 clear_opt (opts->s_mount_opt, ERRORS_PANIC); 534 set_opt (opts->s_mount_opt, ERRORS_RO); 535 break; 536 case Opt_err_cont: 537 clear_opt (opts->s_mount_opt, ERRORS_RO); 538 clear_opt (opts->s_mount_opt, ERRORS_PANIC); 539 set_opt (opts->s_mount_opt, ERRORS_CONT); 540 break; 541 case Opt_nouid32: 542 set_opt (opts->s_mount_opt, NO_UID32); 543 break; 544 case Opt_debug: 545 set_opt (opts->s_mount_opt, DEBUG); 546 break; 547 case Opt_oldalloc: 548 set_opt (opts->s_mount_opt, OLDALLOC); 549 break; 550 case Opt_orlov: 551 clear_opt (opts->s_mount_opt, OLDALLOC); 552 break; 553 case Opt_nobh: 554 set_opt (opts->s_mount_opt, NOBH); 555 break; 556 #ifdef CONFIG_EXT2_FS_XATTR 557 case Opt_user_xattr: 558 set_opt (opts->s_mount_opt, XATTR_USER); 559 break; 560 case Opt_nouser_xattr: 561 clear_opt (opts->s_mount_opt, XATTR_USER); 562 break; 563 #else 564 case Opt_user_xattr: 565 case Opt_nouser_xattr: 566 ext2_msg(sb, KERN_INFO, "(no)user_xattr options" 567 "not supported"); 568 break; 569 #endif 570 #ifdef CONFIG_EXT2_FS_POSIX_ACL 571 case Opt_acl: 572 set_opt(opts->s_mount_opt, POSIX_ACL); 573 break; 574 case Opt_noacl: 575 clear_opt(opts->s_mount_opt, POSIX_ACL); 576 break; 577 #else 578 case Opt_acl: 579 case Opt_noacl: 580 ext2_msg(sb, KERN_INFO, 581 "(no)acl options not supported"); 582 break; 583 #endif 584 case Opt_xip: 585 ext2_msg(sb, KERN_INFO, "use dax instead of xip"); 586 set_opt(opts->s_mount_opt, XIP); 587 fallthrough; 588 case Opt_dax: 589 #ifdef CONFIG_FS_DAX 590 ext2_msg(sb, KERN_WARNING, 591 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk"); 592 set_opt(opts->s_mount_opt, DAX); 593 #else 594 ext2_msg(sb, KERN_INFO, "dax option not supported"); 595 #endif 596 break; 597 598 #if defined(CONFIG_QUOTA) 599 case Opt_quota: 600 case Opt_usrquota: 601 set_opt(opts->s_mount_opt, USRQUOTA); 602 break; 603 604 case Opt_grpquota: 605 set_opt(opts->s_mount_opt, GRPQUOTA); 606 break; 607 #else 608 case Opt_quota: 609 case Opt_usrquota: 610 case Opt_grpquota: 611 ext2_msg(sb, KERN_INFO, 612 "quota operations not supported"); 613 break; 614 #endif 615 616 case Opt_reservation: 617 set_opt(opts->s_mount_opt, RESERVATION); 618 ext2_msg(sb, KERN_INFO, "reservations ON"); 619 break; 620 case Opt_noreservation: 621 clear_opt(opts->s_mount_opt, RESERVATION); 622 ext2_msg(sb, KERN_INFO, "reservations OFF"); 623 break; 624 case Opt_ignore: 625 break; 626 default: 627 return 0; 628 } 629 } 630 return 1; 631 } 632 633 static int ext2_setup_super (struct super_block * sb, 634 struct ext2_super_block * es, 635 int read_only) 636 { 637 int res = 0; 638 struct ext2_sb_info *sbi = EXT2_SB(sb); 639 640 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 641 ext2_msg(sb, KERN_ERR, 642 "error: revision level too high, " 643 "forcing read-only mode"); 644 res = SB_RDONLY; 645 } 646 if (read_only) 647 return res; 648 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 649 ext2_msg(sb, KERN_WARNING, 650 "warning: mounting unchecked fs, " 651 "running e2fsck is recommended"); 652 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 653 ext2_msg(sb, KERN_WARNING, 654 "warning: mounting fs with errors, " 655 "running e2fsck is recommended"); 656 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 657 le16_to_cpu(es->s_mnt_count) >= 658 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 659 ext2_msg(sb, KERN_WARNING, 660 "warning: maximal mount count reached, " 661 "running e2fsck is recommended"); 662 else if (le32_to_cpu(es->s_checkinterval) && 663 (le32_to_cpu(es->s_lastcheck) + 664 le32_to_cpu(es->s_checkinterval) <= 665 ktime_get_real_seconds())) 666 ext2_msg(sb, KERN_WARNING, 667 "warning: checktime reached, " 668 "running e2fsck is recommended"); 669 if (!le16_to_cpu(es->s_max_mnt_count)) 670 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 671 le16_add_cpu(&es->s_mnt_count, 1); 672 if (test_opt (sb, DEBUG)) 673 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, " 674 "bpg=%lu, ipg=%lu, mo=%04lx]", 675 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 676 sbi->s_frag_size, 677 sbi->s_groups_count, 678 EXT2_BLOCKS_PER_GROUP(sb), 679 EXT2_INODES_PER_GROUP(sb), 680 sbi->s_mount_opt); 681 return res; 682 } 683 684 static int ext2_check_descriptors(struct super_block *sb) 685 { 686 int i; 687 struct ext2_sb_info *sbi = EXT2_SB(sb); 688 689 ext2_debug ("Checking group descriptors"); 690 691 for (i = 0; i < sbi->s_groups_count; i++) { 692 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 693 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 694 ext2_fsblk_t last_block = ext2_group_last_block_no(sb, i); 695 696 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 697 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 698 { 699 ext2_error (sb, "ext2_check_descriptors", 700 "Block bitmap for group %d" 701 " not in group (block %lu)!", 702 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 703 return 0; 704 } 705 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 706 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 707 { 708 ext2_error (sb, "ext2_check_descriptors", 709 "Inode bitmap for group %d" 710 " not in group (block %lu)!", 711 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 712 return 0; 713 } 714 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 715 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 716 last_block) 717 { 718 ext2_error (sb, "ext2_check_descriptors", 719 "Inode table for group %d" 720 " not in group (block %lu)!", 721 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 722 return 0; 723 } 724 } 725 return 1; 726 } 727 728 /* 729 * Maximal file size. There is a direct, and {,double-,triple-}indirect 730 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 731 * We need to be 1 filesystem block less than the 2^32 sector limit. 732 */ 733 static loff_t ext2_max_size(int bits) 734 { 735 loff_t res = EXT2_NDIR_BLOCKS; 736 int meta_blocks; 737 unsigned int upper_limit; 738 unsigned int ppb = 1 << (bits-2); 739 740 /* This is calculated to be the largest file size for a 741 * dense, file such that the total number of 742 * sectors in the file, including data and all indirect blocks, 743 * does not exceed 2^32 -1 744 * __u32 i_blocks representing the total number of 745 * 512 bytes blocks of the file 746 */ 747 upper_limit = (1LL << 32) - 1; 748 749 /* total blocks in file system block size */ 750 upper_limit >>= (bits - 9); 751 752 /* Compute how many blocks we can address by block tree */ 753 res += 1LL << (bits-2); 754 res += 1LL << (2*(bits-2)); 755 res += 1LL << (3*(bits-2)); 756 /* Compute how many metadata blocks are needed */ 757 meta_blocks = 1; 758 meta_blocks += 1 + ppb; 759 meta_blocks += 1 + ppb + ppb * ppb; 760 /* Does block tree limit file size? */ 761 if (res + meta_blocks <= upper_limit) 762 goto check_lfs; 763 764 res = upper_limit; 765 /* How many metadata blocks are needed for addressing upper_limit? */ 766 upper_limit -= EXT2_NDIR_BLOCKS; 767 /* indirect blocks */ 768 meta_blocks = 1; 769 upper_limit -= ppb; 770 /* double indirect blocks */ 771 if (upper_limit < ppb * ppb) { 772 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb); 773 res -= meta_blocks; 774 goto check_lfs; 775 } 776 meta_blocks += 1 + ppb; 777 upper_limit -= ppb * ppb; 778 /* tripple indirect blocks for the rest */ 779 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) + 780 DIV_ROUND_UP(upper_limit, ppb*ppb); 781 res -= meta_blocks; 782 check_lfs: 783 res <<= bits; 784 if (res > MAX_LFS_FILESIZE) 785 res = MAX_LFS_FILESIZE; 786 787 return res; 788 } 789 790 static unsigned long descriptor_loc(struct super_block *sb, 791 unsigned long logic_sb_block, 792 int nr) 793 { 794 struct ext2_sb_info *sbi = EXT2_SB(sb); 795 unsigned long bg, first_meta_bg; 796 797 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 798 799 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 800 nr < first_meta_bg) 801 return (logic_sb_block + nr + 1); 802 bg = sbi->s_desc_per_block * nr; 803 804 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg); 805 } 806 807 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 808 { 809 struct buffer_head * bh; 810 struct ext2_sb_info * sbi; 811 struct ext2_super_block * es; 812 struct inode *root; 813 unsigned long block; 814 unsigned long sb_block = get_sb_block(&data); 815 unsigned long logic_sb_block; 816 unsigned long offset = 0; 817 unsigned long def_mount_opts; 818 long ret = -ENOMEM; 819 int blocksize = BLOCK_SIZE; 820 int db_count; 821 int i, j; 822 __le32 features; 823 int err; 824 struct ext2_mount_options opts; 825 826 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 827 if (!sbi) 828 return -ENOMEM; 829 830 sbi->s_blockgroup_lock = 831 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 832 if (!sbi->s_blockgroup_lock) { 833 kfree(sbi); 834 return -ENOMEM; 835 } 836 sb->s_fs_info = sbi; 837 sbi->s_sb_block = sb_block; 838 sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off); 839 840 spin_lock_init(&sbi->s_lock); 841 ret = -EINVAL; 842 843 /* 844 * See what the current blocksize for the device is, and 845 * use that as the blocksize. Otherwise (or if the blocksize 846 * is smaller than the default) use the default. 847 * This is important for devices that have a hardware 848 * sectorsize that is larger than the default. 849 */ 850 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 851 if (!blocksize) { 852 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 853 goto failed_sbi; 854 } 855 856 /* 857 * If the superblock doesn't start on a hardware sector boundary, 858 * calculate the offset. 859 */ 860 if (blocksize != BLOCK_SIZE) { 861 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 862 offset = (sb_block*BLOCK_SIZE) % blocksize; 863 } else { 864 logic_sb_block = sb_block; 865 } 866 867 if (!(bh = sb_bread(sb, logic_sb_block))) { 868 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 869 goto failed_sbi; 870 } 871 /* 872 * Note: s_es must be initialized as soon as possible because 873 * some ext2 macro-instructions depend on its value 874 */ 875 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 876 sbi->s_es = es; 877 sb->s_magic = le16_to_cpu(es->s_magic); 878 879 if (sb->s_magic != EXT2_SUPER_MAGIC) 880 goto cantfind_ext2; 881 882 opts.s_mount_opt = 0; 883 /* Set defaults before we parse the mount options */ 884 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 885 if (def_mount_opts & EXT2_DEFM_DEBUG) 886 set_opt(opts.s_mount_opt, DEBUG); 887 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 888 set_opt(opts.s_mount_opt, GRPID); 889 if (def_mount_opts & EXT2_DEFM_UID16) 890 set_opt(opts.s_mount_opt, NO_UID32); 891 #ifdef CONFIG_EXT2_FS_XATTR 892 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 893 set_opt(opts.s_mount_opt, XATTR_USER); 894 #endif 895 #ifdef CONFIG_EXT2_FS_POSIX_ACL 896 if (def_mount_opts & EXT2_DEFM_ACL) 897 set_opt(opts.s_mount_opt, POSIX_ACL); 898 #endif 899 900 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 901 set_opt(opts.s_mount_opt, ERRORS_PANIC); 902 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 903 set_opt(opts.s_mount_opt, ERRORS_CONT); 904 else 905 set_opt(opts.s_mount_opt, ERRORS_RO); 906 907 opts.s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid)); 908 opts.s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid)); 909 910 set_opt(opts.s_mount_opt, RESERVATION); 911 912 if (!parse_options((char *) data, sb, &opts)) 913 goto failed_mount; 914 915 sbi->s_mount_opt = opts.s_mount_opt; 916 sbi->s_resuid = opts.s_resuid; 917 sbi->s_resgid = opts.s_resgid; 918 919 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | 920 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0); 921 sb->s_iflags |= SB_I_CGROUPWB; 922 923 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 924 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 925 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 926 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 927 ext2_msg(sb, KERN_WARNING, 928 "warning: feature flags set on rev 0 fs, " 929 "running e2fsck is recommended"); 930 /* 931 * Check feature flags regardless of the revision level, since we 932 * previously didn't change the revision level when setting the flags, 933 * so there is a chance incompat flags are set on a rev 0 filesystem. 934 */ 935 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 936 if (features) { 937 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 938 "unsupported optional features (%x)", 939 le32_to_cpu(features)); 940 goto failed_mount; 941 } 942 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 943 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 944 "unsupported optional features (%x)", 945 le32_to_cpu(features)); 946 goto failed_mount; 947 } 948 949 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 950 951 if (test_opt(sb, DAX)) { 952 if (!sbi->s_daxdev) { 953 ext2_msg(sb, KERN_ERR, 954 "DAX unsupported by block device. Turning off DAX."); 955 clear_opt(sbi->s_mount_opt, DAX); 956 } else if (blocksize != PAGE_SIZE) { 957 ext2_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n"); 958 clear_opt(sbi->s_mount_opt, DAX); 959 } 960 } 961 962 /* If the blocksize doesn't match, re-read the thing.. */ 963 if (sb->s_blocksize != blocksize) { 964 brelse(bh); 965 966 if (!sb_set_blocksize(sb, blocksize)) { 967 ext2_msg(sb, KERN_ERR, 968 "error: bad blocksize %d", blocksize); 969 goto failed_sbi; 970 } 971 972 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 973 offset = (sb_block*BLOCK_SIZE) % blocksize; 974 bh = sb_bread(sb, logic_sb_block); 975 if(!bh) { 976 ext2_msg(sb, KERN_ERR, "error: couldn't read" 977 "superblock on 2nd try"); 978 goto failed_sbi; 979 } 980 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 981 sbi->s_es = es; 982 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 983 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 984 goto failed_mount; 985 } 986 } 987 988 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 989 sb->s_max_links = EXT2_LINK_MAX; 990 sb->s_time_min = S32_MIN; 991 sb->s_time_max = S32_MAX; 992 993 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 994 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 995 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 996 } else { 997 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 998 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 999 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 1000 !is_power_of_2(sbi->s_inode_size) || 1001 (sbi->s_inode_size > blocksize)) { 1002 ext2_msg(sb, KERN_ERR, 1003 "error: unsupported inode size: %d", 1004 sbi->s_inode_size); 1005 goto failed_mount; 1006 } 1007 } 1008 1009 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 1010 le32_to_cpu(es->s_log_frag_size); 1011 if (sbi->s_frag_size == 0) 1012 goto cantfind_ext2; 1013 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 1014 1015 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 1016 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 1017 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 1018 1019 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 1020 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 1021 goto cantfind_ext2; 1022 sbi->s_itb_per_group = sbi->s_inodes_per_group / 1023 sbi->s_inodes_per_block; 1024 sbi->s_desc_per_block = sb->s_blocksize / 1025 sizeof (struct ext2_group_desc); 1026 sbi->s_sbh = bh; 1027 sbi->s_mount_state = le16_to_cpu(es->s_state); 1028 sbi->s_addr_per_block_bits = 1029 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 1030 sbi->s_desc_per_block_bits = 1031 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 1032 1033 if (sb->s_magic != EXT2_SUPER_MAGIC) 1034 goto cantfind_ext2; 1035 1036 if (sb->s_blocksize != bh->b_size) { 1037 if (!silent) 1038 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 1039 goto failed_mount; 1040 } 1041 1042 if (sb->s_blocksize != sbi->s_frag_size) { 1043 ext2_msg(sb, KERN_ERR, 1044 "error: fragsize %lu != blocksize %lu" 1045 "(not supported yet)", 1046 sbi->s_frag_size, sb->s_blocksize); 1047 goto failed_mount; 1048 } 1049 1050 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 1051 ext2_msg(sb, KERN_ERR, 1052 "error: #blocks per group too big: %lu", 1053 sbi->s_blocks_per_group); 1054 goto failed_mount; 1055 } 1056 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 1057 ext2_msg(sb, KERN_ERR, 1058 "error: #fragments per group too big: %lu", 1059 sbi->s_frags_per_group); 1060 goto failed_mount; 1061 } 1062 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 1063 ext2_msg(sb, KERN_ERR, 1064 "error: #inodes per group too big: %lu", 1065 sbi->s_inodes_per_group); 1066 goto failed_mount; 1067 } 1068 1069 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 1070 goto cantfind_ext2; 1071 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1072 le32_to_cpu(es->s_first_data_block) - 1) 1073 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1074 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1075 EXT2_DESC_PER_BLOCK(sb); 1076 sbi->s_group_desc = kmalloc_array(db_count, 1077 sizeof(struct buffer_head *), 1078 GFP_KERNEL); 1079 if (sbi->s_group_desc == NULL) { 1080 ret = -ENOMEM; 1081 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1082 goto failed_mount; 1083 } 1084 bgl_lock_init(sbi->s_blockgroup_lock); 1085 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1086 if (!sbi->s_debts) { 1087 ret = -ENOMEM; 1088 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1089 goto failed_mount_group_desc; 1090 } 1091 for (i = 0; i < db_count; i++) { 1092 block = descriptor_loc(sb, logic_sb_block, i); 1093 sbi->s_group_desc[i] = sb_bread(sb, block); 1094 if (!sbi->s_group_desc[i]) { 1095 for (j = 0; j < i; j++) 1096 brelse (sbi->s_group_desc[j]); 1097 ext2_msg(sb, KERN_ERR, 1098 "error: unable to read group descriptors"); 1099 goto failed_mount_group_desc; 1100 } 1101 } 1102 if (!ext2_check_descriptors (sb)) { 1103 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1104 goto failed_mount2; 1105 } 1106 sbi->s_gdb_count = db_count; 1107 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1108 spin_lock_init(&sbi->s_next_gen_lock); 1109 1110 /* per filesystem reservation list head & lock */ 1111 spin_lock_init(&sbi->s_rsv_window_lock); 1112 sbi->s_rsv_window_root = RB_ROOT; 1113 /* 1114 * Add a single, static dummy reservation to the start of the 1115 * reservation window list --- it gives us a placeholder for 1116 * append-at-start-of-list which makes the allocation logic 1117 * _much_ simpler. 1118 */ 1119 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1120 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1121 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1122 sbi->s_rsv_window_head.rsv_goal_size = 0; 1123 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1124 1125 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1126 ext2_count_free_blocks(sb), GFP_KERNEL); 1127 if (!err) { 1128 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1129 ext2_count_free_inodes(sb), GFP_KERNEL); 1130 } 1131 if (!err) { 1132 err = percpu_counter_init(&sbi->s_dirs_counter, 1133 ext2_count_dirs(sb), GFP_KERNEL); 1134 } 1135 if (err) { 1136 ret = err; 1137 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1138 goto failed_mount3; 1139 } 1140 1141 #ifdef CONFIG_EXT2_FS_XATTR 1142 sbi->s_ea_block_cache = ext2_xattr_create_cache(); 1143 if (!sbi->s_ea_block_cache) { 1144 ret = -ENOMEM; 1145 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache"); 1146 goto failed_mount3; 1147 } 1148 #endif 1149 /* 1150 * set up enough so that it can read an inode 1151 */ 1152 sb->s_op = &ext2_sops; 1153 sb->s_export_op = &ext2_export_ops; 1154 sb->s_xattr = ext2_xattr_handlers; 1155 1156 #ifdef CONFIG_QUOTA 1157 sb->dq_op = &dquot_operations; 1158 sb->s_qcop = &ext2_quotactl_ops; 1159 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP; 1160 #endif 1161 1162 root = ext2_iget(sb, EXT2_ROOT_INO); 1163 if (IS_ERR(root)) { 1164 ret = PTR_ERR(root); 1165 goto failed_mount3; 1166 } 1167 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1168 iput(root); 1169 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1170 goto failed_mount3; 1171 } 1172 1173 sb->s_root = d_make_root(root); 1174 if (!sb->s_root) { 1175 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1176 ret = -ENOMEM; 1177 goto failed_mount3; 1178 } 1179 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1180 ext2_msg(sb, KERN_WARNING, 1181 "warning: mounting ext3 filesystem as ext2"); 1182 if (ext2_setup_super (sb, es, sb_rdonly(sb))) 1183 sb->s_flags |= SB_RDONLY; 1184 ext2_write_super(sb); 1185 return 0; 1186 1187 cantfind_ext2: 1188 if (!silent) 1189 ext2_msg(sb, KERN_ERR, 1190 "error: can't find an ext2 filesystem on dev %s.", 1191 sb->s_id); 1192 goto failed_mount; 1193 failed_mount3: 1194 ext2_xattr_destroy_cache(sbi->s_ea_block_cache); 1195 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1196 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1197 percpu_counter_destroy(&sbi->s_dirs_counter); 1198 failed_mount2: 1199 for (i = 0; i < db_count; i++) 1200 brelse(sbi->s_group_desc[i]); 1201 failed_mount_group_desc: 1202 kfree(sbi->s_group_desc); 1203 kfree(sbi->s_debts); 1204 failed_mount: 1205 brelse(bh); 1206 failed_sbi: 1207 fs_put_dax(sbi->s_daxdev); 1208 sb->s_fs_info = NULL; 1209 kfree(sbi->s_blockgroup_lock); 1210 kfree(sbi); 1211 return ret; 1212 } 1213 1214 static void ext2_clear_super_error(struct super_block *sb) 1215 { 1216 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1217 1218 if (buffer_write_io_error(sbh)) { 1219 /* 1220 * Oh, dear. A previous attempt to write the 1221 * superblock failed. This could happen because the 1222 * USB device was yanked out. Or it could happen to 1223 * be a transient write error and maybe the block will 1224 * be remapped. Nothing we can do but to retry the 1225 * write and hope for the best. 1226 */ 1227 ext2_msg(sb, KERN_ERR, 1228 "previous I/O error to superblock detected"); 1229 clear_buffer_write_io_error(sbh); 1230 set_buffer_uptodate(sbh); 1231 } 1232 } 1233 1234 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, 1235 int wait) 1236 { 1237 ext2_clear_super_error(sb); 1238 spin_lock(&EXT2_SB(sb)->s_lock); 1239 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1240 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1241 es->s_wtime = cpu_to_le32(ktime_get_real_seconds()); 1242 /* unlock before we do IO */ 1243 spin_unlock(&EXT2_SB(sb)->s_lock); 1244 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1245 if (wait) 1246 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1247 } 1248 1249 /* 1250 * In the second extended file system, it is not necessary to 1251 * write the super block since we use a mapping of the 1252 * disk super block in a buffer. 1253 * 1254 * However, this function is still used to set the fs valid 1255 * flags to 0. We need to set this flag to 0 since the fs 1256 * may have been checked while mounted and e2fsck may have 1257 * set s_state to EXT2_VALID_FS after some corrections. 1258 */ 1259 static int ext2_sync_fs(struct super_block *sb, int wait) 1260 { 1261 struct ext2_sb_info *sbi = EXT2_SB(sb); 1262 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1263 1264 /* 1265 * Write quota structures to quota file, sync_blockdev() will write 1266 * them to disk later 1267 */ 1268 dquot_writeback_dquots(sb, -1); 1269 1270 spin_lock(&sbi->s_lock); 1271 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1272 ext2_debug("setting valid to 0\n"); 1273 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1274 } 1275 spin_unlock(&sbi->s_lock); 1276 ext2_sync_super(sb, es, wait); 1277 return 0; 1278 } 1279 1280 static int ext2_freeze(struct super_block *sb) 1281 { 1282 struct ext2_sb_info *sbi = EXT2_SB(sb); 1283 1284 /* 1285 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared 1286 * because we have unattached inodes and thus filesystem is not fully 1287 * consistent. 1288 */ 1289 if (atomic_long_read(&sb->s_remove_count)) { 1290 ext2_sync_fs(sb, 1); 1291 return 0; 1292 } 1293 /* Set EXT2_FS_VALID flag */ 1294 spin_lock(&sbi->s_lock); 1295 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); 1296 spin_unlock(&sbi->s_lock); 1297 ext2_sync_super(sb, sbi->s_es, 1); 1298 1299 return 0; 1300 } 1301 1302 static int ext2_unfreeze(struct super_block *sb) 1303 { 1304 /* Just write sb to clear EXT2_VALID_FS flag */ 1305 ext2_write_super(sb); 1306 1307 return 0; 1308 } 1309 1310 static void ext2_write_super(struct super_block *sb) 1311 { 1312 if (!sb_rdonly(sb)) 1313 ext2_sync_fs(sb, 1); 1314 } 1315 1316 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1317 { 1318 struct ext2_sb_info * sbi = EXT2_SB(sb); 1319 struct ext2_super_block * es; 1320 struct ext2_mount_options new_opts; 1321 int err; 1322 1323 sync_filesystem(sb); 1324 1325 spin_lock(&sbi->s_lock); 1326 new_opts.s_mount_opt = sbi->s_mount_opt; 1327 new_opts.s_resuid = sbi->s_resuid; 1328 new_opts.s_resgid = sbi->s_resgid; 1329 spin_unlock(&sbi->s_lock); 1330 1331 if (!parse_options(data, sb, &new_opts)) 1332 return -EINVAL; 1333 1334 spin_lock(&sbi->s_lock); 1335 es = sbi->s_es; 1336 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) { 1337 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1338 "dax flag with busy inodes while remounting"); 1339 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX; 1340 } 1341 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) 1342 goto out_set; 1343 if (*flags & SB_RDONLY) { 1344 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1345 !(sbi->s_mount_state & EXT2_VALID_FS)) 1346 goto out_set; 1347 1348 /* 1349 * OK, we are remounting a valid rw partition rdonly, so set 1350 * the rdonly flag and then mark the partition as valid again. 1351 */ 1352 es->s_state = cpu_to_le16(sbi->s_mount_state); 1353 es->s_mtime = cpu_to_le32(ktime_get_real_seconds()); 1354 spin_unlock(&sbi->s_lock); 1355 1356 err = dquot_suspend(sb, -1); 1357 if (err < 0) 1358 return err; 1359 1360 ext2_sync_super(sb, es, 1); 1361 } else { 1362 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1363 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1364 if (ret) { 1365 spin_unlock(&sbi->s_lock); 1366 ext2_msg(sb, KERN_WARNING, 1367 "warning: couldn't remount RDWR because of " 1368 "unsupported optional features (%x).", 1369 le32_to_cpu(ret)); 1370 return -EROFS; 1371 } 1372 /* 1373 * Mounting a RDONLY partition read-write, so reread and 1374 * store the current valid flag. (It may have been changed 1375 * by e2fsck since we originally mounted the partition.) 1376 */ 1377 sbi->s_mount_state = le16_to_cpu(es->s_state); 1378 if (!ext2_setup_super (sb, es, 0)) 1379 sb->s_flags &= ~SB_RDONLY; 1380 spin_unlock(&sbi->s_lock); 1381 1382 ext2_write_super(sb); 1383 1384 dquot_resume(sb, -1); 1385 } 1386 1387 spin_lock(&sbi->s_lock); 1388 out_set: 1389 sbi->s_mount_opt = new_opts.s_mount_opt; 1390 sbi->s_resuid = new_opts.s_resuid; 1391 sbi->s_resgid = new_opts.s_resgid; 1392 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | 1393 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0); 1394 spin_unlock(&sbi->s_lock); 1395 1396 return 0; 1397 } 1398 1399 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1400 { 1401 struct super_block *sb = dentry->d_sb; 1402 struct ext2_sb_info *sbi = EXT2_SB(sb); 1403 struct ext2_super_block *es = sbi->s_es; 1404 1405 spin_lock(&sbi->s_lock); 1406 1407 if (test_opt (sb, MINIX_DF)) 1408 sbi->s_overhead_last = 0; 1409 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1410 unsigned long i, overhead = 0; 1411 smp_rmb(); 1412 1413 /* 1414 * Compute the overhead (FS structures). This is constant 1415 * for a given filesystem unless the number of block groups 1416 * changes so we cache the previous value until it does. 1417 */ 1418 1419 /* 1420 * All of the blocks before first_data_block are 1421 * overhead 1422 */ 1423 overhead = le32_to_cpu(es->s_first_data_block); 1424 1425 /* 1426 * Add the overhead attributed to the superblock and 1427 * block group descriptors. If the sparse superblocks 1428 * feature is turned on, then not all groups have this. 1429 */ 1430 for (i = 0; i < sbi->s_groups_count; i++) 1431 overhead += ext2_bg_has_super(sb, i) + 1432 ext2_bg_num_gdb(sb, i); 1433 1434 /* 1435 * Every block group has an inode bitmap, a block 1436 * bitmap, and an inode table. 1437 */ 1438 overhead += (sbi->s_groups_count * 1439 (2 + sbi->s_itb_per_group)); 1440 sbi->s_overhead_last = overhead; 1441 smp_wmb(); 1442 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1443 } 1444 1445 buf->f_type = EXT2_SUPER_MAGIC; 1446 buf->f_bsize = sb->s_blocksize; 1447 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1448 buf->f_bfree = ext2_count_free_blocks(sb); 1449 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1450 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1451 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1452 buf->f_bavail = 0; 1453 buf->f_files = le32_to_cpu(es->s_inodes_count); 1454 buf->f_ffree = ext2_count_free_inodes(sb); 1455 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1456 buf->f_namelen = EXT2_NAME_LEN; 1457 buf->f_fsid = uuid_to_fsid(es->s_uuid); 1458 spin_unlock(&sbi->s_lock); 1459 return 0; 1460 } 1461 1462 static struct dentry *ext2_mount(struct file_system_type *fs_type, 1463 int flags, const char *dev_name, void *data) 1464 { 1465 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1466 } 1467 1468 #ifdef CONFIG_QUOTA 1469 1470 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1471 * acquiring the locks... As quota files are never truncated and quota code 1472 * itself serializes the operations (and no one else should touch the files) 1473 * we don't have to be afraid of races */ 1474 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1475 size_t len, loff_t off) 1476 { 1477 struct inode *inode = sb_dqopt(sb)->files[type]; 1478 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1479 int err = 0; 1480 int offset = off & (sb->s_blocksize - 1); 1481 int tocopy; 1482 size_t toread; 1483 struct buffer_head tmp_bh; 1484 struct buffer_head *bh; 1485 loff_t i_size = i_size_read(inode); 1486 1487 if (off > i_size) 1488 return 0; 1489 if (off+len > i_size) 1490 len = i_size-off; 1491 toread = len; 1492 while (toread > 0) { 1493 tocopy = sb->s_blocksize - offset < toread ? 1494 sb->s_blocksize - offset : toread; 1495 1496 tmp_bh.b_state = 0; 1497 tmp_bh.b_size = sb->s_blocksize; 1498 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1499 if (err < 0) 1500 return err; 1501 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1502 memset(data, 0, tocopy); 1503 else { 1504 bh = sb_bread(sb, tmp_bh.b_blocknr); 1505 if (!bh) 1506 return -EIO; 1507 memcpy(data, bh->b_data+offset, tocopy); 1508 brelse(bh); 1509 } 1510 offset = 0; 1511 toread -= tocopy; 1512 data += tocopy; 1513 blk++; 1514 } 1515 return len; 1516 } 1517 1518 /* Write to quotafile */ 1519 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1520 const char *data, size_t len, loff_t off) 1521 { 1522 struct inode *inode = sb_dqopt(sb)->files[type]; 1523 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1524 int err = 0; 1525 int offset = off & (sb->s_blocksize - 1); 1526 int tocopy; 1527 size_t towrite = len; 1528 struct buffer_head tmp_bh; 1529 struct buffer_head *bh; 1530 1531 while (towrite > 0) { 1532 tocopy = sb->s_blocksize - offset < towrite ? 1533 sb->s_blocksize - offset : towrite; 1534 1535 tmp_bh.b_state = 0; 1536 tmp_bh.b_size = sb->s_blocksize; 1537 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1538 if (err < 0) 1539 goto out; 1540 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1541 bh = sb_bread(sb, tmp_bh.b_blocknr); 1542 else 1543 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1544 if (unlikely(!bh)) { 1545 err = -EIO; 1546 goto out; 1547 } 1548 lock_buffer(bh); 1549 memcpy(bh->b_data+offset, data, tocopy); 1550 flush_dcache_page(bh->b_page); 1551 set_buffer_uptodate(bh); 1552 mark_buffer_dirty(bh); 1553 unlock_buffer(bh); 1554 brelse(bh); 1555 offset = 0; 1556 towrite -= tocopy; 1557 data += tocopy; 1558 blk++; 1559 } 1560 out: 1561 if (len == towrite) 1562 return err; 1563 if (inode->i_size < off+len-towrite) 1564 i_size_write(inode, off+len-towrite); 1565 inode_inc_iversion(inode); 1566 inode->i_mtime = inode->i_ctime = current_time(inode); 1567 mark_inode_dirty(inode); 1568 return len - towrite; 1569 } 1570 1571 static int ext2_quota_on(struct super_block *sb, int type, int format_id, 1572 const struct path *path) 1573 { 1574 int err; 1575 struct inode *inode; 1576 1577 err = dquot_quota_on(sb, type, format_id, path); 1578 if (err) 1579 return err; 1580 1581 inode = d_inode(path->dentry); 1582 inode_lock(inode); 1583 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL; 1584 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE, 1585 S_NOATIME | S_IMMUTABLE); 1586 inode_unlock(inode); 1587 mark_inode_dirty(inode); 1588 1589 return 0; 1590 } 1591 1592 static int ext2_quota_off(struct super_block *sb, int type) 1593 { 1594 struct inode *inode = sb_dqopt(sb)->files[type]; 1595 int err; 1596 1597 if (!inode || !igrab(inode)) 1598 goto out; 1599 1600 err = dquot_quota_off(sb, type); 1601 if (err) 1602 goto out_put; 1603 1604 inode_lock(inode); 1605 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL); 1606 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE); 1607 inode_unlock(inode); 1608 mark_inode_dirty(inode); 1609 out_put: 1610 iput(inode); 1611 return err; 1612 out: 1613 return dquot_quota_off(sb, type); 1614 } 1615 1616 #endif 1617 1618 static struct file_system_type ext2_fs_type = { 1619 .owner = THIS_MODULE, 1620 .name = "ext2", 1621 .mount = ext2_mount, 1622 .kill_sb = kill_block_super, 1623 .fs_flags = FS_REQUIRES_DEV, 1624 }; 1625 MODULE_ALIAS_FS("ext2"); 1626 1627 static int __init init_ext2_fs(void) 1628 { 1629 int err; 1630 1631 err = init_inodecache(); 1632 if (err) 1633 return err; 1634 err = register_filesystem(&ext2_fs_type); 1635 if (err) 1636 goto out; 1637 return 0; 1638 out: 1639 destroy_inodecache(); 1640 return err; 1641 } 1642 1643 static void __exit exit_ext2_fs(void) 1644 { 1645 unregister_filesystem(&ext2_fs_type); 1646 destroy_inodecache(); 1647 } 1648 1649 MODULE_AUTHOR("Remy Card and others"); 1650 MODULE_DESCRIPTION("Second Extended Filesystem"); 1651 MODULE_LICENSE("GPL"); 1652 module_init(init_ext2_fs) 1653 module_exit(exit_ext2_fs) 1654