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, USRQUOTA)) 300 seq_puts(seq, ",usrquota"); 301 302 if (test_opt(sb, GRPQUOTA)) 303 seq_puts(seq, ",grpquota"); 304 305 if (test_opt(sb, XIP)) 306 seq_puts(seq, ",xip"); 307 308 if (test_opt(sb, DAX)) 309 seq_puts(seq, ",dax"); 310 311 if (!test_opt(sb, RESERVATION)) 312 seq_puts(seq, ",noreservation"); 313 314 spin_unlock(&sbi->s_lock); 315 return 0; 316 } 317 318 #ifdef CONFIG_QUOTA 319 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 320 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 321 static int ext2_quota_on(struct super_block *sb, int type, int format_id, 322 const struct path *path); 323 static struct dquot **ext2_get_dquots(struct inode *inode) 324 { 325 return EXT2_I(inode)->i_dquot; 326 } 327 328 static const struct quotactl_ops ext2_quotactl_ops = { 329 .quota_on = ext2_quota_on, 330 .quota_off = ext2_quota_off, 331 .quota_sync = dquot_quota_sync, 332 .get_state = dquot_get_state, 333 .set_info = dquot_set_dqinfo, 334 .get_dqblk = dquot_get_dqblk, 335 .set_dqblk = dquot_set_dqblk, 336 .get_nextdqblk = dquot_get_next_dqblk, 337 }; 338 #endif 339 340 static const struct super_operations ext2_sops = { 341 .alloc_inode = ext2_alloc_inode, 342 .free_inode = ext2_free_in_core_inode, 343 .write_inode = ext2_write_inode, 344 .evict_inode = ext2_evict_inode, 345 .put_super = ext2_put_super, 346 .sync_fs = ext2_sync_fs, 347 .freeze_fs = ext2_freeze, 348 .unfreeze_fs = ext2_unfreeze, 349 .statfs = ext2_statfs, 350 .remount_fs = ext2_remount, 351 .show_options = ext2_show_options, 352 #ifdef CONFIG_QUOTA 353 .quota_read = ext2_quota_read, 354 .quota_write = ext2_quota_write, 355 .get_dquots = ext2_get_dquots, 356 #endif 357 }; 358 359 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 360 u64 ino, u32 generation) 361 { 362 struct inode *inode; 363 364 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 365 return ERR_PTR(-ESTALE); 366 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 367 return ERR_PTR(-ESTALE); 368 369 /* 370 * ext2_iget isn't quite right if the inode is currently unallocated! 371 * However ext2_iget currently does appropriate checks to handle stale 372 * inodes so everything is OK. 373 */ 374 inode = ext2_iget(sb, ino); 375 if (IS_ERR(inode)) 376 return ERR_CAST(inode); 377 if (generation && inode->i_generation != generation) { 378 /* we didn't find the right inode.. */ 379 iput(inode); 380 return ERR_PTR(-ESTALE); 381 } 382 return inode; 383 } 384 385 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 386 int fh_len, int fh_type) 387 { 388 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 389 ext2_nfs_get_inode); 390 } 391 392 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 393 int fh_len, int fh_type) 394 { 395 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 396 ext2_nfs_get_inode); 397 } 398 399 static const struct export_operations ext2_export_ops = { 400 .fh_to_dentry = ext2_fh_to_dentry, 401 .fh_to_parent = ext2_fh_to_parent, 402 .get_parent = ext2_get_parent, 403 }; 404 405 static unsigned long get_sb_block(void **data) 406 { 407 unsigned long sb_block; 408 char *options = (char *) *data; 409 410 if (!options || strncmp(options, "sb=", 3) != 0) 411 return 1; /* Default location */ 412 options += 3; 413 sb_block = simple_strtoul(options, &options, 0); 414 if (*options && *options != ',') { 415 printk("EXT2-fs: Invalid sb specification: %s\n", 416 (char *) *data); 417 return 1; 418 } 419 if (*options == ',') 420 options++; 421 *data = (void *) options; 422 return sb_block; 423 } 424 425 enum { 426 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 427 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 428 Opt_err_ro, Opt_nouid32, Opt_debug, 429 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 430 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota, 431 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 432 }; 433 434 static const match_table_t tokens = { 435 {Opt_bsd_df, "bsddf"}, 436 {Opt_minix_df, "minixdf"}, 437 {Opt_grpid, "grpid"}, 438 {Opt_grpid, "bsdgroups"}, 439 {Opt_nogrpid, "nogrpid"}, 440 {Opt_nogrpid, "sysvgroups"}, 441 {Opt_resgid, "resgid=%u"}, 442 {Opt_resuid, "resuid=%u"}, 443 {Opt_sb, "sb=%u"}, 444 {Opt_err_cont, "errors=continue"}, 445 {Opt_err_panic, "errors=panic"}, 446 {Opt_err_ro, "errors=remount-ro"}, 447 {Opt_nouid32, "nouid32"}, 448 {Opt_debug, "debug"}, 449 {Opt_oldalloc, "oldalloc"}, 450 {Opt_orlov, "orlov"}, 451 {Opt_nobh, "nobh"}, 452 {Opt_user_xattr, "user_xattr"}, 453 {Opt_nouser_xattr, "nouser_xattr"}, 454 {Opt_acl, "acl"}, 455 {Opt_noacl, "noacl"}, 456 {Opt_xip, "xip"}, 457 {Opt_dax, "dax"}, 458 {Opt_grpquota, "grpquota"}, 459 {Opt_ignore, "noquota"}, 460 {Opt_quota, "quota"}, 461 {Opt_usrquota, "usrquota"}, 462 {Opt_reservation, "reservation"}, 463 {Opt_noreservation, "noreservation"}, 464 {Opt_err, NULL} 465 }; 466 467 static int parse_options(char *options, struct super_block *sb, 468 struct ext2_mount_options *opts) 469 { 470 char *p; 471 substring_t args[MAX_OPT_ARGS]; 472 int option; 473 kuid_t uid; 474 kgid_t gid; 475 476 if (!options) 477 return 1; 478 479 while ((p = strsep (&options, ",")) != NULL) { 480 int token; 481 if (!*p) 482 continue; 483 484 token = match_token(p, tokens, args); 485 switch (token) { 486 case Opt_bsd_df: 487 clear_opt (opts->s_mount_opt, MINIX_DF); 488 break; 489 case Opt_minix_df: 490 set_opt (opts->s_mount_opt, MINIX_DF); 491 break; 492 case Opt_grpid: 493 set_opt (opts->s_mount_opt, GRPID); 494 break; 495 case Opt_nogrpid: 496 clear_opt (opts->s_mount_opt, GRPID); 497 break; 498 case Opt_resuid: 499 if (match_int(&args[0], &option)) 500 return 0; 501 uid = make_kuid(current_user_ns(), option); 502 if (!uid_valid(uid)) { 503 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option); 504 return 0; 505 506 } 507 opts->s_resuid = uid; 508 break; 509 case Opt_resgid: 510 if (match_int(&args[0], &option)) 511 return 0; 512 gid = make_kgid(current_user_ns(), option); 513 if (!gid_valid(gid)) { 514 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option); 515 return 0; 516 } 517 opts->s_resgid = gid; 518 break; 519 case Opt_sb: 520 /* handled by get_sb_block() instead of here */ 521 /* *sb_block = match_int(&args[0]); */ 522 break; 523 case Opt_err_panic: 524 clear_opt (opts->s_mount_opt, ERRORS_CONT); 525 clear_opt (opts->s_mount_opt, ERRORS_RO); 526 set_opt (opts->s_mount_opt, ERRORS_PANIC); 527 break; 528 case Opt_err_ro: 529 clear_opt (opts->s_mount_opt, ERRORS_CONT); 530 clear_opt (opts->s_mount_opt, ERRORS_PANIC); 531 set_opt (opts->s_mount_opt, ERRORS_RO); 532 break; 533 case Opt_err_cont: 534 clear_opt (opts->s_mount_opt, ERRORS_RO); 535 clear_opt (opts->s_mount_opt, ERRORS_PANIC); 536 set_opt (opts->s_mount_opt, ERRORS_CONT); 537 break; 538 case Opt_nouid32: 539 set_opt (opts->s_mount_opt, NO_UID32); 540 break; 541 case Opt_debug: 542 set_opt (opts->s_mount_opt, DEBUG); 543 break; 544 case Opt_oldalloc: 545 set_opt (opts->s_mount_opt, OLDALLOC); 546 break; 547 case Opt_orlov: 548 clear_opt (opts->s_mount_opt, OLDALLOC); 549 break; 550 case Opt_nobh: 551 ext2_msg(sb, KERN_INFO, 552 "nobh option not supported"); 553 break; 554 #ifdef CONFIG_EXT2_FS_XATTR 555 case Opt_user_xattr: 556 set_opt (opts->s_mount_opt, XATTR_USER); 557 break; 558 case Opt_nouser_xattr: 559 clear_opt (opts->s_mount_opt, XATTR_USER); 560 break; 561 #else 562 case Opt_user_xattr: 563 case Opt_nouser_xattr: 564 ext2_msg(sb, KERN_INFO, "(no)user_xattr options" 565 "not supported"); 566 break; 567 #endif 568 #ifdef CONFIG_EXT2_FS_POSIX_ACL 569 case Opt_acl: 570 set_opt(opts->s_mount_opt, POSIX_ACL); 571 break; 572 case Opt_noacl: 573 clear_opt(opts->s_mount_opt, POSIX_ACL); 574 break; 575 #else 576 case Opt_acl: 577 case Opt_noacl: 578 ext2_msg(sb, KERN_INFO, 579 "(no)acl options not supported"); 580 break; 581 #endif 582 case Opt_xip: 583 ext2_msg(sb, KERN_INFO, "use dax instead of xip"); 584 set_opt(opts->s_mount_opt, XIP); 585 fallthrough; 586 case Opt_dax: 587 #ifdef CONFIG_FS_DAX 588 ext2_msg(sb, KERN_WARNING, 589 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk"); 590 set_opt(opts->s_mount_opt, DAX); 591 #else 592 ext2_msg(sb, KERN_INFO, "dax option not supported"); 593 #endif 594 break; 595 596 #if defined(CONFIG_QUOTA) 597 case Opt_quota: 598 case Opt_usrquota: 599 set_opt(opts->s_mount_opt, USRQUOTA); 600 break; 601 602 case Opt_grpquota: 603 set_opt(opts->s_mount_opt, GRPQUOTA); 604 break; 605 #else 606 case Opt_quota: 607 case Opt_usrquota: 608 case Opt_grpquota: 609 ext2_msg(sb, KERN_INFO, 610 "quota operations not supported"); 611 break; 612 #endif 613 614 case Opt_reservation: 615 set_opt(opts->s_mount_opt, RESERVATION); 616 ext2_msg(sb, KERN_INFO, "reservations ON"); 617 break; 618 case Opt_noreservation: 619 clear_opt(opts->s_mount_opt, RESERVATION); 620 ext2_msg(sb, KERN_INFO, "reservations OFF"); 621 break; 622 case Opt_ignore: 623 break; 624 default: 625 return 0; 626 } 627 } 628 return 1; 629 } 630 631 static int ext2_setup_super (struct super_block * sb, 632 struct ext2_super_block * es, 633 int read_only) 634 { 635 int res = 0; 636 struct ext2_sb_info *sbi = EXT2_SB(sb); 637 638 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 639 ext2_msg(sb, KERN_ERR, 640 "error: revision level too high, " 641 "forcing read-only mode"); 642 res = SB_RDONLY; 643 } 644 if (read_only) 645 return res; 646 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 647 ext2_msg(sb, KERN_WARNING, 648 "warning: mounting unchecked fs, " 649 "running e2fsck is recommended"); 650 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 651 ext2_msg(sb, KERN_WARNING, 652 "warning: mounting fs with errors, " 653 "running e2fsck is recommended"); 654 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 655 le16_to_cpu(es->s_mnt_count) >= 656 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 657 ext2_msg(sb, KERN_WARNING, 658 "warning: maximal mount count reached, " 659 "running e2fsck is recommended"); 660 else if (le32_to_cpu(es->s_checkinterval) && 661 (le32_to_cpu(es->s_lastcheck) + 662 le32_to_cpu(es->s_checkinterval) <= 663 ktime_get_real_seconds())) 664 ext2_msg(sb, KERN_WARNING, 665 "warning: checktime reached, " 666 "running e2fsck is recommended"); 667 if (!le16_to_cpu(es->s_max_mnt_count)) 668 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 669 le16_add_cpu(&es->s_mnt_count, 1); 670 if (test_opt (sb, DEBUG)) 671 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, " 672 "bpg=%lu, ipg=%lu, mo=%04lx]", 673 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 674 sbi->s_frag_size, 675 sbi->s_groups_count, 676 EXT2_BLOCKS_PER_GROUP(sb), 677 EXT2_INODES_PER_GROUP(sb), 678 sbi->s_mount_opt); 679 return res; 680 } 681 682 static int ext2_check_descriptors(struct super_block *sb) 683 { 684 int i; 685 struct ext2_sb_info *sbi = EXT2_SB(sb); 686 687 ext2_debug ("Checking group descriptors"); 688 689 for (i = 0; i < sbi->s_groups_count; i++) { 690 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 691 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 692 ext2_fsblk_t last_block = ext2_group_last_block_no(sb, i); 693 694 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 695 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 696 { 697 ext2_error (sb, "ext2_check_descriptors", 698 "Block bitmap for group %d" 699 " not in group (block %lu)!", 700 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 701 return 0; 702 } 703 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 704 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 705 { 706 ext2_error (sb, "ext2_check_descriptors", 707 "Inode bitmap for group %d" 708 " not in group (block %lu)!", 709 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 710 return 0; 711 } 712 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 713 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 714 last_block) 715 { 716 ext2_error (sb, "ext2_check_descriptors", 717 "Inode table for group %d" 718 " not in group (block %lu)!", 719 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 720 return 0; 721 } 722 } 723 return 1; 724 } 725 726 /* 727 * Maximal file size. There is a direct, and {,double-,triple-}indirect 728 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 729 * We need to be 1 filesystem block less than the 2^32 sector limit. 730 */ 731 static loff_t ext2_max_size(int bits) 732 { 733 loff_t res = EXT2_NDIR_BLOCKS; 734 int meta_blocks; 735 unsigned int upper_limit; 736 unsigned int ppb = 1 << (bits-2); 737 738 /* This is calculated to be the largest file size for a 739 * dense, file such that the total number of 740 * sectors in the file, including data and all indirect blocks, 741 * does not exceed 2^32 -1 742 * __u32 i_blocks representing the total number of 743 * 512 bytes blocks of the file 744 */ 745 upper_limit = (1LL << 32) - 1; 746 747 /* total blocks in file system block size */ 748 upper_limit >>= (bits - 9); 749 750 /* Compute how many blocks we can address by block tree */ 751 res += 1LL << (bits-2); 752 res += 1LL << (2*(bits-2)); 753 res += 1LL << (3*(bits-2)); 754 /* Compute how many metadata blocks are needed */ 755 meta_blocks = 1; 756 meta_blocks += 1 + ppb; 757 meta_blocks += 1 + ppb + ppb * ppb; 758 /* Does block tree limit file size? */ 759 if (res + meta_blocks <= upper_limit) 760 goto check_lfs; 761 762 res = upper_limit; 763 /* How many metadata blocks are needed for addressing upper_limit? */ 764 upper_limit -= EXT2_NDIR_BLOCKS; 765 /* indirect blocks */ 766 meta_blocks = 1; 767 upper_limit -= ppb; 768 /* double indirect blocks */ 769 if (upper_limit < ppb * ppb) { 770 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb); 771 res -= meta_blocks; 772 goto check_lfs; 773 } 774 meta_blocks += 1 + ppb; 775 upper_limit -= ppb * ppb; 776 /* tripple indirect blocks for the rest */ 777 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) + 778 DIV_ROUND_UP(upper_limit, ppb*ppb); 779 res -= meta_blocks; 780 check_lfs: 781 res <<= bits; 782 if (res > MAX_LFS_FILESIZE) 783 res = MAX_LFS_FILESIZE; 784 785 return res; 786 } 787 788 static unsigned long descriptor_loc(struct super_block *sb, 789 unsigned long logic_sb_block, 790 int nr) 791 { 792 struct ext2_sb_info *sbi = EXT2_SB(sb); 793 unsigned long bg, first_meta_bg; 794 795 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 796 797 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 798 nr < first_meta_bg) 799 return (logic_sb_block + nr + 1); 800 bg = sbi->s_desc_per_block * nr; 801 802 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg); 803 } 804 805 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 806 { 807 struct buffer_head * bh; 808 struct ext2_sb_info * sbi; 809 struct ext2_super_block * es; 810 struct inode *root; 811 unsigned long block; 812 unsigned long sb_block = get_sb_block(&data); 813 unsigned long logic_sb_block; 814 unsigned long offset = 0; 815 unsigned long def_mount_opts; 816 long ret = -ENOMEM; 817 int blocksize = BLOCK_SIZE; 818 int db_count; 819 int i, j; 820 __le32 features; 821 int err; 822 struct ext2_mount_options opts; 823 824 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 825 if (!sbi) 826 return -ENOMEM; 827 828 sbi->s_blockgroup_lock = 829 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 830 if (!sbi->s_blockgroup_lock) { 831 kfree(sbi); 832 return -ENOMEM; 833 } 834 sb->s_fs_info = sbi; 835 sbi->s_sb_block = sb_block; 836 sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off); 837 838 spin_lock_init(&sbi->s_lock); 839 ret = -EINVAL; 840 841 /* 842 * See what the current blocksize for the device is, and 843 * use that as the blocksize. Otherwise (or if the blocksize 844 * is smaller than the default) use the default. 845 * This is important for devices that have a hardware 846 * sectorsize that is larger than the default. 847 */ 848 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 849 if (!blocksize) { 850 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 851 goto failed_sbi; 852 } 853 854 /* 855 * If the superblock doesn't start on a hardware sector boundary, 856 * calculate the offset. 857 */ 858 if (blocksize != BLOCK_SIZE) { 859 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 860 offset = (sb_block*BLOCK_SIZE) % blocksize; 861 } else { 862 logic_sb_block = sb_block; 863 } 864 865 if (!(bh = sb_bread(sb, logic_sb_block))) { 866 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 867 goto failed_sbi; 868 } 869 /* 870 * Note: s_es must be initialized as soon as possible because 871 * some ext2 macro-instructions depend on its value 872 */ 873 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 874 sbi->s_es = es; 875 sb->s_magic = le16_to_cpu(es->s_magic); 876 877 if (sb->s_magic != EXT2_SUPER_MAGIC) 878 goto cantfind_ext2; 879 880 opts.s_mount_opt = 0; 881 /* Set defaults before we parse the mount options */ 882 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 883 if (def_mount_opts & EXT2_DEFM_DEBUG) 884 set_opt(opts.s_mount_opt, DEBUG); 885 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 886 set_opt(opts.s_mount_opt, GRPID); 887 if (def_mount_opts & EXT2_DEFM_UID16) 888 set_opt(opts.s_mount_opt, NO_UID32); 889 #ifdef CONFIG_EXT2_FS_XATTR 890 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 891 set_opt(opts.s_mount_opt, XATTR_USER); 892 #endif 893 #ifdef CONFIG_EXT2_FS_POSIX_ACL 894 if (def_mount_opts & EXT2_DEFM_ACL) 895 set_opt(opts.s_mount_opt, POSIX_ACL); 896 #endif 897 898 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 899 set_opt(opts.s_mount_opt, ERRORS_PANIC); 900 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 901 set_opt(opts.s_mount_opt, ERRORS_CONT); 902 else 903 set_opt(opts.s_mount_opt, ERRORS_RO); 904 905 opts.s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid)); 906 opts.s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid)); 907 908 set_opt(opts.s_mount_opt, RESERVATION); 909 910 if (!parse_options((char *) data, sb, &opts)) 911 goto failed_mount; 912 913 sbi->s_mount_opt = opts.s_mount_opt; 914 sbi->s_resuid = opts.s_resuid; 915 sbi->s_resgid = opts.s_resgid; 916 917 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | 918 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0); 919 sb->s_iflags |= SB_I_CGROUPWB; 920 921 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 922 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 923 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 924 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 925 ext2_msg(sb, KERN_WARNING, 926 "warning: feature flags set on rev 0 fs, " 927 "running e2fsck is recommended"); 928 /* 929 * Check feature flags regardless of the revision level, since we 930 * previously didn't change the revision level when setting the flags, 931 * so there is a chance incompat flags are set on a rev 0 filesystem. 932 */ 933 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 934 if (features) { 935 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 936 "unsupported optional features (%x)", 937 le32_to_cpu(features)); 938 goto failed_mount; 939 } 940 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 941 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 942 "unsupported optional features (%x)", 943 le32_to_cpu(features)); 944 goto failed_mount; 945 } 946 947 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 948 949 if (test_opt(sb, DAX)) { 950 if (!sbi->s_daxdev) { 951 ext2_msg(sb, KERN_ERR, 952 "DAX unsupported by block device. Turning off DAX."); 953 clear_opt(sbi->s_mount_opt, DAX); 954 } else if (blocksize != PAGE_SIZE) { 955 ext2_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n"); 956 clear_opt(sbi->s_mount_opt, DAX); 957 } 958 } 959 960 /* If the blocksize doesn't match, re-read the thing.. */ 961 if (sb->s_blocksize != blocksize) { 962 brelse(bh); 963 964 if (!sb_set_blocksize(sb, blocksize)) { 965 ext2_msg(sb, KERN_ERR, 966 "error: bad blocksize %d", blocksize); 967 goto failed_sbi; 968 } 969 970 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 971 offset = (sb_block*BLOCK_SIZE) % blocksize; 972 bh = sb_bread(sb, logic_sb_block); 973 if(!bh) { 974 ext2_msg(sb, KERN_ERR, "error: couldn't read" 975 "superblock on 2nd try"); 976 goto failed_sbi; 977 } 978 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 979 sbi->s_es = es; 980 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 981 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 982 goto failed_mount; 983 } 984 } 985 986 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 987 sb->s_max_links = EXT2_LINK_MAX; 988 sb->s_time_min = S32_MIN; 989 sb->s_time_max = S32_MAX; 990 991 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 992 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 993 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 994 } else { 995 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 996 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 997 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 998 !is_power_of_2(sbi->s_inode_size) || 999 (sbi->s_inode_size > blocksize)) { 1000 ext2_msg(sb, KERN_ERR, 1001 "error: unsupported inode size: %d", 1002 sbi->s_inode_size); 1003 goto failed_mount; 1004 } 1005 } 1006 1007 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 1008 le32_to_cpu(es->s_log_frag_size); 1009 if (sbi->s_frag_size == 0) 1010 goto cantfind_ext2; 1011 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 1012 1013 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 1014 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 1015 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 1016 1017 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 1018 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 1019 goto cantfind_ext2; 1020 sbi->s_itb_per_group = sbi->s_inodes_per_group / 1021 sbi->s_inodes_per_block; 1022 sbi->s_desc_per_block = sb->s_blocksize / 1023 sizeof (struct ext2_group_desc); 1024 sbi->s_sbh = bh; 1025 sbi->s_mount_state = le16_to_cpu(es->s_state); 1026 sbi->s_addr_per_block_bits = 1027 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 1028 sbi->s_desc_per_block_bits = 1029 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 1030 1031 if (sb->s_magic != EXT2_SUPER_MAGIC) 1032 goto cantfind_ext2; 1033 1034 if (sb->s_blocksize != bh->b_size) { 1035 if (!silent) 1036 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 1037 goto failed_mount; 1038 } 1039 1040 if (sb->s_blocksize != sbi->s_frag_size) { 1041 ext2_msg(sb, KERN_ERR, 1042 "error: fragsize %lu != blocksize %lu" 1043 "(not supported yet)", 1044 sbi->s_frag_size, sb->s_blocksize); 1045 goto failed_mount; 1046 } 1047 1048 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 1049 ext2_msg(sb, KERN_ERR, 1050 "error: #blocks per group too big: %lu", 1051 sbi->s_blocks_per_group); 1052 goto failed_mount; 1053 } 1054 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 1055 ext2_msg(sb, KERN_ERR, 1056 "error: #fragments per group too big: %lu", 1057 sbi->s_frags_per_group); 1058 goto failed_mount; 1059 } 1060 if (sbi->s_inodes_per_group < sbi->s_inodes_per_block || 1061 sbi->s_inodes_per_group > sb->s_blocksize * 8) { 1062 ext2_msg(sb, KERN_ERR, 1063 "error: invalid #inodes per group: %lu", 1064 sbi->s_inodes_per_group); 1065 goto failed_mount; 1066 } 1067 1068 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 1069 goto cantfind_ext2; 1070 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1071 le32_to_cpu(es->s_first_data_block) - 1) 1072 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1073 if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group != 1074 le32_to_cpu(es->s_inodes_count)) { 1075 ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu", 1076 le32_to_cpu(es->s_inodes_count), 1077 (u64)sbi->s_groups_count * sbi->s_inodes_per_group); 1078 goto failed_mount; 1079 } 1080 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1081 EXT2_DESC_PER_BLOCK(sb); 1082 sbi->s_group_desc = kmalloc_array(db_count, 1083 sizeof(struct buffer_head *), 1084 GFP_KERNEL); 1085 if (sbi->s_group_desc == NULL) { 1086 ret = -ENOMEM; 1087 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1088 goto failed_mount; 1089 } 1090 bgl_lock_init(sbi->s_blockgroup_lock); 1091 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1092 if (!sbi->s_debts) { 1093 ret = -ENOMEM; 1094 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1095 goto failed_mount_group_desc; 1096 } 1097 for (i = 0; i < db_count; i++) { 1098 block = descriptor_loc(sb, logic_sb_block, i); 1099 sbi->s_group_desc[i] = sb_bread(sb, block); 1100 if (!sbi->s_group_desc[i]) { 1101 for (j = 0; j < i; j++) 1102 brelse (sbi->s_group_desc[j]); 1103 ext2_msg(sb, KERN_ERR, 1104 "error: unable to read group descriptors"); 1105 goto failed_mount_group_desc; 1106 } 1107 } 1108 if (!ext2_check_descriptors (sb)) { 1109 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1110 goto failed_mount2; 1111 } 1112 sbi->s_gdb_count = db_count; 1113 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1114 spin_lock_init(&sbi->s_next_gen_lock); 1115 1116 /* per filesystem reservation list head & lock */ 1117 spin_lock_init(&sbi->s_rsv_window_lock); 1118 sbi->s_rsv_window_root = RB_ROOT; 1119 /* 1120 * Add a single, static dummy reservation to the start of the 1121 * reservation window list --- it gives us a placeholder for 1122 * append-at-start-of-list which makes the allocation logic 1123 * _much_ simpler. 1124 */ 1125 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1126 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1127 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1128 sbi->s_rsv_window_head.rsv_goal_size = 0; 1129 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1130 1131 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1132 ext2_count_free_blocks(sb), GFP_KERNEL); 1133 if (!err) { 1134 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1135 ext2_count_free_inodes(sb), GFP_KERNEL); 1136 } 1137 if (!err) { 1138 err = percpu_counter_init(&sbi->s_dirs_counter, 1139 ext2_count_dirs(sb), GFP_KERNEL); 1140 } 1141 if (err) { 1142 ret = err; 1143 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1144 goto failed_mount3; 1145 } 1146 1147 #ifdef CONFIG_EXT2_FS_XATTR 1148 sbi->s_ea_block_cache = ext2_xattr_create_cache(); 1149 if (!sbi->s_ea_block_cache) { 1150 ret = -ENOMEM; 1151 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache"); 1152 goto failed_mount3; 1153 } 1154 #endif 1155 /* 1156 * set up enough so that it can read an inode 1157 */ 1158 sb->s_op = &ext2_sops; 1159 sb->s_export_op = &ext2_export_ops; 1160 sb->s_xattr = ext2_xattr_handlers; 1161 1162 #ifdef CONFIG_QUOTA 1163 sb->dq_op = &dquot_operations; 1164 sb->s_qcop = &ext2_quotactl_ops; 1165 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP; 1166 #endif 1167 1168 root = ext2_iget(sb, EXT2_ROOT_INO); 1169 if (IS_ERR(root)) { 1170 ret = PTR_ERR(root); 1171 goto failed_mount3; 1172 } 1173 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1174 iput(root); 1175 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1176 goto failed_mount3; 1177 } 1178 1179 sb->s_root = d_make_root(root); 1180 if (!sb->s_root) { 1181 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1182 ret = -ENOMEM; 1183 goto failed_mount3; 1184 } 1185 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1186 ext2_msg(sb, KERN_WARNING, 1187 "warning: mounting ext3 filesystem as ext2"); 1188 if (ext2_setup_super (sb, es, sb_rdonly(sb))) 1189 sb->s_flags |= SB_RDONLY; 1190 ext2_write_super(sb); 1191 return 0; 1192 1193 cantfind_ext2: 1194 if (!silent) 1195 ext2_msg(sb, KERN_ERR, 1196 "error: can't find an ext2 filesystem on dev %s.", 1197 sb->s_id); 1198 goto failed_mount; 1199 failed_mount3: 1200 ext2_xattr_destroy_cache(sbi->s_ea_block_cache); 1201 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1202 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1203 percpu_counter_destroy(&sbi->s_dirs_counter); 1204 failed_mount2: 1205 for (i = 0; i < db_count; i++) 1206 brelse(sbi->s_group_desc[i]); 1207 failed_mount_group_desc: 1208 kfree(sbi->s_group_desc); 1209 kfree(sbi->s_debts); 1210 failed_mount: 1211 brelse(bh); 1212 failed_sbi: 1213 fs_put_dax(sbi->s_daxdev); 1214 sb->s_fs_info = NULL; 1215 kfree(sbi->s_blockgroup_lock); 1216 kfree(sbi); 1217 return ret; 1218 } 1219 1220 static void ext2_clear_super_error(struct super_block *sb) 1221 { 1222 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1223 1224 if (buffer_write_io_error(sbh)) { 1225 /* 1226 * Oh, dear. A previous attempt to write the 1227 * superblock failed. This could happen because the 1228 * USB device was yanked out. Or it could happen to 1229 * be a transient write error and maybe the block will 1230 * be remapped. Nothing we can do but to retry the 1231 * write and hope for the best. 1232 */ 1233 ext2_msg(sb, KERN_ERR, 1234 "previous I/O error to superblock detected"); 1235 clear_buffer_write_io_error(sbh); 1236 set_buffer_uptodate(sbh); 1237 } 1238 } 1239 1240 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, 1241 int wait) 1242 { 1243 ext2_clear_super_error(sb); 1244 spin_lock(&EXT2_SB(sb)->s_lock); 1245 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1246 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1247 es->s_wtime = cpu_to_le32(ktime_get_real_seconds()); 1248 /* unlock before we do IO */ 1249 spin_unlock(&EXT2_SB(sb)->s_lock); 1250 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1251 if (wait) 1252 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1253 } 1254 1255 /* 1256 * In the second extended file system, it is not necessary to 1257 * write the super block since we use a mapping of the 1258 * disk super block in a buffer. 1259 * 1260 * However, this function is still used to set the fs valid 1261 * flags to 0. We need to set this flag to 0 since the fs 1262 * may have been checked while mounted and e2fsck may have 1263 * set s_state to EXT2_VALID_FS after some corrections. 1264 */ 1265 static int ext2_sync_fs(struct super_block *sb, int wait) 1266 { 1267 struct ext2_sb_info *sbi = EXT2_SB(sb); 1268 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1269 1270 /* 1271 * Write quota structures to quota file, sync_blockdev() will write 1272 * them to disk later 1273 */ 1274 dquot_writeback_dquots(sb, -1); 1275 1276 spin_lock(&sbi->s_lock); 1277 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1278 ext2_debug("setting valid to 0\n"); 1279 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1280 } 1281 spin_unlock(&sbi->s_lock); 1282 ext2_sync_super(sb, es, wait); 1283 return 0; 1284 } 1285 1286 static int ext2_freeze(struct super_block *sb) 1287 { 1288 struct ext2_sb_info *sbi = EXT2_SB(sb); 1289 1290 /* 1291 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared 1292 * because we have unattached inodes and thus filesystem is not fully 1293 * consistent. 1294 */ 1295 if (atomic_long_read(&sb->s_remove_count)) { 1296 ext2_sync_fs(sb, 1); 1297 return 0; 1298 } 1299 /* Set EXT2_FS_VALID flag */ 1300 spin_lock(&sbi->s_lock); 1301 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); 1302 spin_unlock(&sbi->s_lock); 1303 ext2_sync_super(sb, sbi->s_es, 1); 1304 1305 return 0; 1306 } 1307 1308 static int ext2_unfreeze(struct super_block *sb) 1309 { 1310 /* Just write sb to clear EXT2_VALID_FS flag */ 1311 ext2_write_super(sb); 1312 1313 return 0; 1314 } 1315 1316 static void ext2_write_super(struct super_block *sb) 1317 { 1318 if (!sb_rdonly(sb)) 1319 ext2_sync_fs(sb, 1); 1320 } 1321 1322 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1323 { 1324 struct ext2_sb_info * sbi = EXT2_SB(sb); 1325 struct ext2_super_block * es; 1326 struct ext2_mount_options new_opts; 1327 int err; 1328 1329 sync_filesystem(sb); 1330 1331 spin_lock(&sbi->s_lock); 1332 new_opts.s_mount_opt = sbi->s_mount_opt; 1333 new_opts.s_resuid = sbi->s_resuid; 1334 new_opts.s_resgid = sbi->s_resgid; 1335 spin_unlock(&sbi->s_lock); 1336 1337 if (!parse_options(data, sb, &new_opts)) 1338 return -EINVAL; 1339 1340 spin_lock(&sbi->s_lock); 1341 es = sbi->s_es; 1342 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) { 1343 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1344 "dax flag with busy inodes while remounting"); 1345 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX; 1346 } 1347 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) 1348 goto out_set; 1349 if (*flags & SB_RDONLY) { 1350 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1351 !(sbi->s_mount_state & EXT2_VALID_FS)) 1352 goto out_set; 1353 1354 /* 1355 * OK, we are remounting a valid rw partition rdonly, so set 1356 * the rdonly flag and then mark the partition as valid again. 1357 */ 1358 es->s_state = cpu_to_le16(sbi->s_mount_state); 1359 es->s_mtime = cpu_to_le32(ktime_get_real_seconds()); 1360 spin_unlock(&sbi->s_lock); 1361 1362 err = dquot_suspend(sb, -1); 1363 if (err < 0) 1364 return err; 1365 1366 ext2_sync_super(sb, es, 1); 1367 } else { 1368 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1369 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1370 if (ret) { 1371 spin_unlock(&sbi->s_lock); 1372 ext2_msg(sb, KERN_WARNING, 1373 "warning: couldn't remount RDWR because of " 1374 "unsupported optional features (%x).", 1375 le32_to_cpu(ret)); 1376 return -EROFS; 1377 } 1378 /* 1379 * Mounting a RDONLY partition read-write, so reread and 1380 * store the current valid flag. (It may have been changed 1381 * by e2fsck since we originally mounted the partition.) 1382 */ 1383 sbi->s_mount_state = le16_to_cpu(es->s_state); 1384 if (!ext2_setup_super (sb, es, 0)) 1385 sb->s_flags &= ~SB_RDONLY; 1386 spin_unlock(&sbi->s_lock); 1387 1388 ext2_write_super(sb); 1389 1390 dquot_resume(sb, -1); 1391 } 1392 1393 spin_lock(&sbi->s_lock); 1394 out_set: 1395 sbi->s_mount_opt = new_opts.s_mount_opt; 1396 sbi->s_resuid = new_opts.s_resuid; 1397 sbi->s_resgid = new_opts.s_resgid; 1398 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | 1399 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0); 1400 spin_unlock(&sbi->s_lock); 1401 1402 return 0; 1403 } 1404 1405 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1406 { 1407 struct super_block *sb = dentry->d_sb; 1408 struct ext2_sb_info *sbi = EXT2_SB(sb); 1409 struct ext2_super_block *es = sbi->s_es; 1410 1411 spin_lock(&sbi->s_lock); 1412 1413 if (test_opt (sb, MINIX_DF)) 1414 sbi->s_overhead_last = 0; 1415 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1416 unsigned long i, overhead = 0; 1417 smp_rmb(); 1418 1419 /* 1420 * Compute the overhead (FS structures). This is constant 1421 * for a given filesystem unless the number of block groups 1422 * changes so we cache the previous value until it does. 1423 */ 1424 1425 /* 1426 * All of the blocks before first_data_block are 1427 * overhead 1428 */ 1429 overhead = le32_to_cpu(es->s_first_data_block); 1430 1431 /* 1432 * Add the overhead attributed to the superblock and 1433 * block group descriptors. If the sparse superblocks 1434 * feature is turned on, then not all groups have this. 1435 */ 1436 for (i = 0; i < sbi->s_groups_count; i++) 1437 overhead += ext2_bg_has_super(sb, i) + 1438 ext2_bg_num_gdb(sb, i); 1439 1440 /* 1441 * Every block group has an inode bitmap, a block 1442 * bitmap, and an inode table. 1443 */ 1444 overhead += (sbi->s_groups_count * 1445 (2 + sbi->s_itb_per_group)); 1446 sbi->s_overhead_last = overhead; 1447 smp_wmb(); 1448 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1449 } 1450 1451 buf->f_type = EXT2_SUPER_MAGIC; 1452 buf->f_bsize = sb->s_blocksize; 1453 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1454 buf->f_bfree = ext2_count_free_blocks(sb); 1455 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1456 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1457 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1458 buf->f_bavail = 0; 1459 buf->f_files = le32_to_cpu(es->s_inodes_count); 1460 buf->f_ffree = ext2_count_free_inodes(sb); 1461 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1462 buf->f_namelen = EXT2_NAME_LEN; 1463 buf->f_fsid = uuid_to_fsid(es->s_uuid); 1464 spin_unlock(&sbi->s_lock); 1465 return 0; 1466 } 1467 1468 static struct dentry *ext2_mount(struct file_system_type *fs_type, 1469 int flags, const char *dev_name, void *data) 1470 { 1471 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1472 } 1473 1474 #ifdef CONFIG_QUOTA 1475 1476 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1477 * acquiring the locks... As quota files are never truncated and quota code 1478 * itself serializes the operations (and no one else should touch the files) 1479 * we don't have to be afraid of races */ 1480 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1481 size_t len, loff_t off) 1482 { 1483 struct inode *inode = sb_dqopt(sb)->files[type]; 1484 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1485 int err = 0; 1486 int offset = off & (sb->s_blocksize - 1); 1487 int tocopy; 1488 size_t toread; 1489 struct buffer_head tmp_bh; 1490 struct buffer_head *bh; 1491 loff_t i_size = i_size_read(inode); 1492 1493 if (off > i_size) 1494 return 0; 1495 if (off+len > i_size) 1496 len = i_size-off; 1497 toread = len; 1498 while (toread > 0) { 1499 tocopy = min_t(size_t, sb->s_blocksize - offset, toread); 1500 1501 tmp_bh.b_state = 0; 1502 tmp_bh.b_size = sb->s_blocksize; 1503 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1504 if (err < 0) 1505 return err; 1506 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1507 memset(data, 0, tocopy); 1508 else { 1509 bh = sb_bread(sb, tmp_bh.b_blocknr); 1510 if (!bh) 1511 return -EIO; 1512 memcpy(data, bh->b_data+offset, tocopy); 1513 brelse(bh); 1514 } 1515 offset = 0; 1516 toread -= tocopy; 1517 data += tocopy; 1518 blk++; 1519 } 1520 return len; 1521 } 1522 1523 /* Write to quotafile */ 1524 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1525 const char *data, size_t len, loff_t off) 1526 { 1527 struct inode *inode = sb_dqopt(sb)->files[type]; 1528 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1529 int err = 0; 1530 int offset = off & (sb->s_blocksize - 1); 1531 int tocopy; 1532 size_t towrite = len; 1533 struct buffer_head tmp_bh; 1534 struct buffer_head *bh; 1535 1536 while (towrite > 0) { 1537 tocopy = min_t(size_t, sb->s_blocksize - offset, towrite); 1538 1539 tmp_bh.b_state = 0; 1540 tmp_bh.b_size = sb->s_blocksize; 1541 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1542 if (err < 0) 1543 goto out; 1544 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1545 bh = sb_bread(sb, tmp_bh.b_blocknr); 1546 else 1547 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1548 if (unlikely(!bh)) { 1549 err = -EIO; 1550 goto out; 1551 } 1552 lock_buffer(bh); 1553 memcpy(bh->b_data+offset, data, tocopy); 1554 flush_dcache_page(bh->b_page); 1555 set_buffer_uptodate(bh); 1556 mark_buffer_dirty(bh); 1557 unlock_buffer(bh); 1558 brelse(bh); 1559 offset = 0; 1560 towrite -= tocopy; 1561 data += tocopy; 1562 blk++; 1563 } 1564 out: 1565 if (len == towrite) 1566 return err; 1567 if (inode->i_size < off+len-towrite) 1568 i_size_write(inode, off+len-towrite); 1569 inode_inc_iversion(inode); 1570 inode->i_mtime = inode->i_ctime = current_time(inode); 1571 mark_inode_dirty(inode); 1572 return len - towrite; 1573 } 1574 1575 static int ext2_quota_on(struct super_block *sb, int type, int format_id, 1576 const struct path *path) 1577 { 1578 int err; 1579 struct inode *inode; 1580 1581 err = dquot_quota_on(sb, type, format_id, path); 1582 if (err) 1583 return err; 1584 1585 inode = d_inode(path->dentry); 1586 inode_lock(inode); 1587 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL; 1588 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE, 1589 S_NOATIME | S_IMMUTABLE); 1590 inode_unlock(inode); 1591 mark_inode_dirty(inode); 1592 1593 return 0; 1594 } 1595 1596 static int ext2_quota_off(struct super_block *sb, int type) 1597 { 1598 struct inode *inode = sb_dqopt(sb)->files[type]; 1599 int err; 1600 1601 if (!inode || !igrab(inode)) 1602 goto out; 1603 1604 err = dquot_quota_off(sb, type); 1605 if (err) 1606 goto out_put; 1607 1608 inode_lock(inode); 1609 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL); 1610 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE); 1611 inode_unlock(inode); 1612 mark_inode_dirty(inode); 1613 out_put: 1614 iput(inode); 1615 return err; 1616 out: 1617 return dquot_quota_off(sb, type); 1618 } 1619 1620 #endif 1621 1622 static struct file_system_type ext2_fs_type = { 1623 .owner = THIS_MODULE, 1624 .name = "ext2", 1625 .mount = ext2_mount, 1626 .kill_sb = kill_block_super, 1627 .fs_flags = FS_REQUIRES_DEV, 1628 }; 1629 MODULE_ALIAS_FS("ext2"); 1630 1631 static int __init init_ext2_fs(void) 1632 { 1633 int err; 1634 1635 err = init_inodecache(); 1636 if (err) 1637 return err; 1638 err = register_filesystem(&ext2_fs_type); 1639 if (err) 1640 goto out; 1641 return 0; 1642 out: 1643 destroy_inodecache(); 1644 return err; 1645 } 1646 1647 static void __exit exit_ext2_fs(void) 1648 { 1649 unregister_filesystem(&ext2_fs_type); 1650 destroy_inodecache(); 1651 } 1652 1653 MODULE_AUTHOR("Remy Card and others"); 1654 MODULE_DESCRIPTION("Second Extended Filesystem"); 1655 MODULE_LICENSE("GPL"); 1656 module_init(init_ext2_fs) 1657 module_exit(exit_ext2_fs) 1658