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 42static void ext2_write_super(struct super_block *sb); 43static int ext2_remount (struct super_block * sb, int * flags, char * data); 44static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf); 45static int ext2_sync_fs(struct super_block *sb, int wait); 46static int ext2_freeze(struct super_block *sb); 47static int ext2_unfreeze(struct super_block *sb); 48 49void 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 84void 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 */ 103void 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 129static int ext2_quota_off(struct super_block *sb, int type); 130 131static 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 139static inline void ext2_quota_off_umount(struct super_block *sb) 140{ 141} 142#endif 143 144static 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 kvfree(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, NULL); 175 kfree(sbi); 176} 177 178static struct kmem_cache * ext2_inode_cachep; 179 180static 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 195static void ext2_free_in_core_inode(struct inode *inode) 196{ 197 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 198} 199 200static 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 212static 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_ACCOUNT, 217 offsetof(struct ext2_inode_info, i_data), 218 sizeof_field(struct ext2_inode_info, i_data), 219 init_once); 220 if (ext2_inode_cachep == NULL) 221 return -ENOMEM; 222 return 0; 223} 224 225static void destroy_inodecache(void) 226{ 227 /* 228 * Make sure all delayed rcu free inodes are flushed before we 229 * destroy cache. 230 */ 231 rcu_barrier(); 232 kmem_cache_destroy(ext2_inode_cachep); 233} 234 235static int ext2_show_options(struct seq_file *seq, struct dentry *root) 236{ 237 struct super_block *sb = root->d_sb; 238 struct ext2_sb_info *sbi = EXT2_SB(sb); 239 struct ext2_super_block *es = sbi->s_es; 240 unsigned long def_mount_opts; 241 242 spin_lock(&sbi->s_lock); 243 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 244 245 if (sbi->s_sb_block != 1) 246 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 247 if (test_opt(sb, MINIX_DF)) 248 seq_puts(seq, ",minixdf"); 249 if (test_opt(sb, GRPID)) 250 seq_puts(seq, ",grpid"); 251 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 252 seq_puts(seq, ",nogrpid"); 253 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) || 254 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 255 seq_printf(seq, ",resuid=%u", 256 from_kuid_munged(&init_user_ns, sbi->s_resuid)); 257 } 258 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) || 259 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 260 seq_printf(seq, ",resgid=%u", 261 from_kgid_munged(&init_user_ns, sbi->s_resgid)); 262 } 263 if (test_opt(sb, ERRORS_RO)) { 264 int def_errors = le16_to_cpu(es->s_errors); 265 266 if (def_errors == EXT2_ERRORS_PANIC || 267 def_errors == EXT2_ERRORS_CONTINUE) { 268 seq_puts(seq, ",errors=remount-ro"); 269 } 270 } 271 if (test_opt(sb, ERRORS_CONT)) 272 seq_puts(seq, ",errors=continue"); 273 if (test_opt(sb, ERRORS_PANIC)) 274 seq_puts(seq, ",errors=panic"); 275 if (test_opt(sb, NO_UID32)) 276 seq_puts(seq, ",nouid32"); 277 if (test_opt(sb, DEBUG)) 278 seq_puts(seq, ",debug"); 279 if (test_opt(sb, OLDALLOC)) 280 seq_puts(seq, ",oldalloc"); 281 282#ifdef CONFIG_EXT2_FS_XATTR 283 if (test_opt(sb, XATTR_USER)) 284 seq_puts(seq, ",user_xattr"); 285 if (!test_opt(sb, XATTR_USER) && 286 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 287 seq_puts(seq, ",nouser_xattr"); 288 } 289#endif 290 291#ifdef CONFIG_EXT2_FS_POSIX_ACL 292 if (test_opt(sb, POSIX_ACL)) 293 seq_puts(seq, ",acl"); 294 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 295 seq_puts(seq, ",noacl"); 296#endif 297 298 if (test_opt(sb, USRQUOTA)) 299 seq_puts(seq, ",usrquota"); 300 301 if (test_opt(sb, GRPQUOTA)) 302 seq_puts(seq, ",grpquota"); 303 304 if (test_opt(sb, XIP)) 305 seq_puts(seq, ",xip"); 306 307 if (test_opt(sb, DAX)) 308 seq_puts(seq, ",dax"); 309 310 if (!test_opt(sb, RESERVATION)) 311 seq_puts(seq, ",noreservation"); 312 313 spin_unlock(&sbi->s_lock); 314 return 0; 315} 316 317#ifdef CONFIG_QUOTA 318static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 319static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 320static int ext2_quota_on(struct super_block *sb, int type, int format_id, 321 const struct path *path); 322static struct dquot __rcu **ext2_get_dquots(struct inode *inode) 323{ 324 return EXT2_I(inode)->i_dquot; 325} 326 327static const struct quotactl_ops ext2_quotactl_ops = { 328 .quota_on = ext2_quota_on, 329 .quota_off = ext2_quota_off, 330 .quota_sync = dquot_quota_sync, 331 .get_state = dquot_get_state, 332 .set_info = dquot_set_dqinfo, 333 .get_dqblk = dquot_get_dqblk, 334 .set_dqblk = dquot_set_dqblk, 335 .get_nextdqblk = dquot_get_next_dqblk, 336}; 337#endif 338 339static const struct super_operations ext2_sops = { 340 .alloc_inode = ext2_alloc_inode, 341 .free_inode = ext2_free_in_core_inode, 342 .write_inode = ext2_write_inode, 343 .evict_inode = ext2_evict_inode, 344 .put_super = ext2_put_super, 345 .sync_fs = ext2_sync_fs, 346 .freeze_fs = ext2_freeze, 347 .unfreeze_fs = ext2_unfreeze, 348 .statfs = ext2_statfs, 349 .remount_fs = ext2_remount, 350 .show_options = ext2_show_options, 351#ifdef CONFIG_QUOTA 352 .quota_read = ext2_quota_read, 353 .quota_write = ext2_quota_write, 354 .get_dquots = ext2_get_dquots, 355#endif 356}; 357 358static struct inode *ext2_nfs_get_inode(struct super_block *sb, 359 u64 ino, u32 generation) 360{ 361 struct inode *inode; 362 363 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 364 return ERR_PTR(-ESTALE); 365 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 366 return ERR_PTR(-ESTALE); 367 368 /* 369 * ext2_iget isn't quite right if the inode is currently unallocated! 370 * However ext2_iget currently does appropriate checks to handle stale 371 * inodes so everything is OK. 372 */ 373 inode = ext2_iget(sb, ino); 374 if (IS_ERR(inode)) 375 return ERR_CAST(inode); 376 if (generation && inode->i_generation != generation) { 377 /* we didn't find the right inode.. */ 378 iput(inode); 379 return ERR_PTR(-ESTALE); 380 } 381 return inode; 382} 383 384static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 385 int fh_len, int fh_type) 386{ 387 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 388 ext2_nfs_get_inode); 389} 390 391static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 392 int fh_len, int fh_type) 393{ 394 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 395 ext2_nfs_get_inode); 396} 397 398static const struct export_operations ext2_export_ops = { 399 .encode_fh = generic_encode_ino32_fh, 400 .fh_to_dentry = ext2_fh_to_dentry, 401 .fh_to_parent = ext2_fh_to_parent, 402 .get_parent = ext2_get_parent, 403}; 404 405static 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 425enum { 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 434static 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 467static 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 631static 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, gc=%lu, " 672 "bpg=%lu, ipg=%lu, mo=%04lx]", 673 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 674 sbi->s_groups_count, 675 EXT2_BLOCKS_PER_GROUP(sb), 676 EXT2_INODES_PER_GROUP(sb), 677 sbi->s_mount_opt); 678 return res; 679} 680 681static int ext2_check_descriptors(struct super_block *sb) 682{ 683 int i; 684 struct ext2_sb_info *sbi = EXT2_SB(sb); 685 686 ext2_debug ("Checking group descriptors"); 687 688 for (i = 0; i < sbi->s_groups_count; i++) { 689 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 690 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 691 ext2_fsblk_t last_block = ext2_group_last_block_no(sb, i); 692 693 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 694 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 695 { 696 ext2_error (sb, "ext2_check_descriptors", 697 "Block bitmap for group %d" 698 " not in group (block %lu)!", 699 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 700 return 0; 701 } 702 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 703 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 704 { 705 ext2_error (sb, "ext2_check_descriptors", 706 "Inode bitmap for group %d" 707 " not in group (block %lu)!", 708 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 709 return 0; 710 } 711 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 712 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 713 last_block) 714 { 715 ext2_error (sb, "ext2_check_descriptors", 716 "Inode table for group %d" 717 " not in group (block %lu)!", 718 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 719 return 0; 720 } 721 } 722 return 1; 723} 724 725/* 726 * Maximal file size. There is a direct, and {,double-,triple-}indirect 727 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 728 * We need to be 1 filesystem block less than the 2^32 sector limit. 729 */ 730static loff_t ext2_max_size(int bits) 731{ 732 loff_t res = EXT2_NDIR_BLOCKS; 733 int meta_blocks; 734 unsigned int upper_limit; 735 unsigned int ppb = 1 << (bits-2); 736 737 /* This is calculated to be the largest file size for a 738 * dense, file such that the total number of 739 * sectors in the file, including data and all indirect blocks, 740 * does not exceed 2^32 -1 741 * __u32 i_blocks representing the total number of 742 * 512 bytes blocks of the file 743 */ 744 upper_limit = (1LL << 32) - 1; 745 746 /* total blocks in file system block size */ 747 upper_limit >>= (bits - 9); 748 749 /* Compute how many blocks we can address by block tree */ 750 res += 1LL << (bits-2); 751 res += 1LL << (2*(bits-2)); 752 res += 1LL << (3*(bits-2)); 753 /* Compute how many metadata blocks are needed */ 754 meta_blocks = 1; 755 meta_blocks += 1 + ppb; 756 meta_blocks += 1 + ppb + ppb * ppb; 757 /* Does block tree limit file size? */ 758 if (res + meta_blocks <= upper_limit) 759 goto check_lfs; 760 761 res = upper_limit; 762 /* How many metadata blocks are needed for addressing upper_limit? */ 763 upper_limit -= EXT2_NDIR_BLOCKS; 764 /* indirect blocks */ 765 meta_blocks = 1; 766 upper_limit -= ppb; 767 /* double indirect blocks */ 768 if (upper_limit < ppb * ppb) { 769 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb); 770 res -= meta_blocks; 771 goto check_lfs; 772 } 773 meta_blocks += 1 + ppb; 774 upper_limit -= ppb * ppb; 775 /* tripple indirect blocks for the rest */ 776 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) + 777 DIV_ROUND_UP(upper_limit, ppb*ppb); 778 res -= meta_blocks; 779check_lfs: 780 res <<= bits; 781 if (res > MAX_LFS_FILESIZE) 782 res = MAX_LFS_FILESIZE; 783 784 return res; 785} 786 787static unsigned long descriptor_loc(struct super_block *sb, 788 unsigned long logic_sb_block, 789 int nr) 790{ 791 struct ext2_sb_info *sbi = EXT2_SB(sb); 792 unsigned long bg, first_meta_bg; 793 794 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 795 796 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 797 nr < first_meta_bg) 798 return (logic_sb_block + nr + 1); 799 bg = sbi->s_desc_per_block * nr; 800 801 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg); 802} 803 804static int ext2_fill_super(struct super_block *sb, void *data, int silent) 805{ 806 struct buffer_head * bh; 807 struct ext2_sb_info * sbi; 808 struct ext2_super_block * es; 809 struct inode *root; 810 unsigned long block; 811 unsigned long sb_block = get_sb_block(&data); 812 unsigned long logic_sb_block; 813 unsigned long offset = 0; 814 unsigned long def_mount_opts; 815 long ret = -ENOMEM; 816 int blocksize = BLOCK_SIZE; 817 int db_count; 818 int i, j; 819 __le32 features; 820 int err; 821 struct ext2_mount_options opts; 822 823 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 824 if (!sbi) 825 return -ENOMEM; 826 827 sbi->s_blockgroup_lock = 828 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 829 if (!sbi->s_blockgroup_lock) { 830 kfree(sbi); 831 return -ENOMEM; 832 } 833 sb->s_fs_info = sbi; 834 sbi->s_sb_block = sb_block; 835 sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off, 836 NULL, NULL); 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 if (le32_to_cpu(es->s_log_block_size) > 948 (EXT2_MAX_BLOCK_LOG_SIZE - BLOCK_SIZE_BITS)) { 949 ext2_msg(sb, KERN_ERR, 950 "Invalid log block size: %u", 951 le32_to_cpu(es->s_log_block_size)); 952 goto failed_mount; 953 } 954 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 955 956 if (test_opt(sb, DAX)) { 957 if (!sbi->s_daxdev) { 958 ext2_msg(sb, KERN_ERR, 959 "DAX unsupported by block device. Turning off DAX."); 960 clear_opt(sbi->s_mount_opt, DAX); 961 } else if (blocksize != PAGE_SIZE) { 962 ext2_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n"); 963 clear_opt(sbi->s_mount_opt, DAX); 964 } 965 } 966 967 /* If the blocksize doesn't match, re-read the thing.. */ 968 if (sb->s_blocksize != blocksize) { 969 brelse(bh); 970 971 if (!sb_set_blocksize(sb, blocksize)) { 972 ext2_msg(sb, KERN_ERR, 973 "error: bad blocksize %d", blocksize); 974 goto failed_sbi; 975 } 976 977 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 978 offset = (sb_block*BLOCK_SIZE) % blocksize; 979 bh = sb_bread(sb, logic_sb_block); 980 if(!bh) { 981 ext2_msg(sb, KERN_ERR, "error: couldn't read" 982 "superblock on 2nd try"); 983 goto failed_sbi; 984 } 985 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 986 sbi->s_es = es; 987 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 988 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 989 goto failed_mount; 990 } 991 } 992 993 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 994 sb->s_max_links = EXT2_LINK_MAX; 995 sb->s_time_min = S32_MIN; 996 sb->s_time_max = S32_MAX; 997 998 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 999 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 1000 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 1001 } else { 1002 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 1003 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 1004 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 1005 !is_power_of_2(sbi->s_inode_size) || 1006 (sbi->s_inode_size > blocksize)) { 1007 ext2_msg(sb, KERN_ERR, 1008 "error: unsupported inode size: %d", 1009 sbi->s_inode_size); 1010 goto failed_mount; 1011 } 1012 } 1013 1014 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_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 (es->s_log_frag_size != es->s_log_block_size) { 1041 ext2_msg(sb, KERN_ERR, 1042 "error: fragsize log %u != blocksize log %u", 1043 le32_to_cpu(es->s_log_frag_size), sb->s_blocksize_bits); 1044 goto failed_mount; 1045 } 1046 1047 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 1048 ext2_msg(sb, KERN_ERR, 1049 "error: #blocks per group too big: %lu", 1050 sbi->s_blocks_per_group); 1051 goto failed_mount; 1052 } 1053 /* At least inode table, bitmaps, and sb have to fit in one group */ 1054 if (sbi->s_blocks_per_group <= sbi->s_itb_per_group + 3) { 1055 ext2_msg(sb, KERN_ERR, 1056 "error: #blocks per group smaller than metadata size: %lu <= %lu", 1057 sbi->s_blocks_per_group, sbi->s_inodes_per_group + 3); 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 if (sb_bdev_nr_blocks(sb) < le32_to_cpu(es->s_blocks_count)) { 1068 ext2_msg(sb, KERN_ERR, 1069 "bad geometry: block count %u exceeds size of device (%u blocks)", 1070 le32_to_cpu(es->s_blocks_count), 1071 (unsigned)sb_bdev_nr_blocks(sb)); 1072 goto failed_mount; 1073 } 1074 1075 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1076 le32_to_cpu(es->s_first_data_block) - 1) 1077 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1078 if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group != 1079 le32_to_cpu(es->s_inodes_count)) { 1080 ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu", 1081 le32_to_cpu(es->s_inodes_count), 1082 (u64)sbi->s_groups_count * sbi->s_inodes_per_group); 1083 goto failed_mount; 1084 } 1085 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1086 EXT2_DESC_PER_BLOCK(sb); 1087 sbi->s_group_desc = kvmalloc_array(db_count, 1088 sizeof(struct buffer_head *), 1089 GFP_KERNEL); 1090 if (sbi->s_group_desc == NULL) { 1091 ret = -ENOMEM; 1092 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1093 goto failed_mount; 1094 } 1095 bgl_lock_init(sbi->s_blockgroup_lock); 1096 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1097 if (!sbi->s_debts) { 1098 ret = -ENOMEM; 1099 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1100 goto failed_mount_group_desc; 1101 } 1102 for (i = 0; i < db_count; i++) { 1103 block = descriptor_loc(sb, logic_sb_block, i); 1104 sbi->s_group_desc[i] = sb_bread(sb, block); 1105 if (!sbi->s_group_desc[i]) { 1106 for (j = 0; j < i; j++) 1107 brelse (sbi->s_group_desc[j]); 1108 ext2_msg(sb, KERN_ERR, 1109 "error: unable to read group descriptors"); 1110 goto failed_mount_group_desc; 1111 } 1112 } 1113 if (!ext2_check_descriptors (sb)) { 1114 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1115 goto failed_mount2; 1116 } 1117 sbi->s_gdb_count = db_count; 1118 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1119 spin_lock_init(&sbi->s_next_gen_lock); 1120 1121 /* per filesystem reservation list head & lock */ 1122 spin_lock_init(&sbi->s_rsv_window_lock); 1123 sbi->s_rsv_window_root = RB_ROOT; 1124 /* 1125 * Add a single, static dummy reservation to the start of the 1126 * reservation window list --- it gives us a placeholder for 1127 * append-at-start-of-list which makes the allocation logic 1128 * _much_ simpler. 1129 */ 1130 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1131 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1132 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1133 sbi->s_rsv_window_head.rsv_goal_size = 0; 1134 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1135 1136 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1137 ext2_count_free_blocks(sb), GFP_KERNEL); 1138 if (!err) { 1139 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1140 ext2_count_free_inodes(sb), GFP_KERNEL); 1141 } 1142 if (!err) { 1143 err = percpu_counter_init(&sbi->s_dirs_counter, 1144 ext2_count_dirs(sb), GFP_KERNEL); 1145 } 1146 if (err) { 1147 ret = err; 1148 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1149 goto failed_mount3; 1150 } 1151 1152#ifdef CONFIG_EXT2_FS_XATTR 1153 sbi->s_ea_block_cache = ext2_xattr_create_cache(); 1154 if (!sbi->s_ea_block_cache) { 1155 ret = -ENOMEM; 1156 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache"); 1157 goto failed_mount3; 1158 } 1159#endif 1160 /* 1161 * set up enough so that it can read an inode 1162 */ 1163 sb->s_op = &ext2_sops; 1164 sb->s_export_op = &ext2_export_ops; 1165 sb->s_xattr = ext2_xattr_handlers; 1166 1167#ifdef CONFIG_QUOTA 1168 sb->dq_op = &dquot_operations; 1169 sb->s_qcop = &ext2_quotactl_ops; 1170 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP; 1171#endif 1172 1173 root = ext2_iget(sb, EXT2_ROOT_INO); 1174 if (IS_ERR(root)) { 1175 ret = PTR_ERR(root); 1176 goto failed_mount3; 1177 } 1178 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1179 iput(root); 1180 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1181 goto failed_mount3; 1182 } 1183 1184 sb->s_root = d_make_root(root); 1185 if (!sb->s_root) { 1186 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1187 ret = -ENOMEM; 1188 goto failed_mount3; 1189 } 1190 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1191 ext2_msg(sb, KERN_WARNING, 1192 "warning: mounting ext3 filesystem as ext2"); 1193 if (ext2_setup_super (sb, es, sb_rdonly(sb))) 1194 sb->s_flags |= SB_RDONLY; 1195 ext2_write_super(sb); 1196 return 0; 1197 1198cantfind_ext2: 1199 if (!silent) 1200 ext2_msg(sb, KERN_ERR, 1201 "error: can't find an ext2 filesystem on dev %s.", 1202 sb->s_id); 1203 goto failed_mount; 1204failed_mount3: 1205 ext2_xattr_destroy_cache(sbi->s_ea_block_cache); 1206 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1207 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1208 percpu_counter_destroy(&sbi->s_dirs_counter); 1209failed_mount2: 1210 for (i = 0; i < db_count; i++) 1211 brelse(sbi->s_group_desc[i]); 1212failed_mount_group_desc: 1213 kvfree(sbi->s_group_desc); 1214 kfree(sbi->s_debts); 1215failed_mount: 1216 brelse(bh); 1217failed_sbi: 1218 fs_put_dax(sbi->s_daxdev, NULL); 1219 sb->s_fs_info = NULL; 1220 kfree(sbi->s_blockgroup_lock); 1221 kfree(sbi); 1222 return ret; 1223} 1224 1225static void ext2_clear_super_error(struct super_block *sb) 1226{ 1227 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1228 1229 if (buffer_write_io_error(sbh)) { 1230 /* 1231 * Oh, dear. A previous attempt to write the 1232 * superblock failed. This could happen because the 1233 * USB device was yanked out. Or it could happen to 1234 * be a transient write error and maybe the block will 1235 * be remapped. Nothing we can do but to retry the 1236 * write and hope for the best. 1237 */ 1238 ext2_msg(sb, KERN_ERR, 1239 "previous I/O error to superblock detected"); 1240 clear_buffer_write_io_error(sbh); 1241 set_buffer_uptodate(sbh); 1242 } 1243} 1244 1245void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, 1246 int wait) 1247{ 1248 ext2_clear_super_error(sb); 1249 spin_lock(&EXT2_SB(sb)->s_lock); 1250 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1251 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1252 es->s_wtime = cpu_to_le32(ktime_get_real_seconds()); 1253 /* unlock before we do IO */ 1254 spin_unlock(&EXT2_SB(sb)->s_lock); 1255 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1256 if (wait) 1257 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1258} 1259 1260/* 1261 * In the second extended file system, it is not necessary to 1262 * write the super block since we use a mapping of the 1263 * disk super block in a buffer. 1264 * 1265 * However, this function is still used to set the fs valid 1266 * flags to 0. We need to set this flag to 0 since the fs 1267 * may have been checked while mounted and e2fsck may have 1268 * set s_state to EXT2_VALID_FS after some corrections. 1269 */ 1270static int ext2_sync_fs(struct super_block *sb, int wait) 1271{ 1272 struct ext2_sb_info *sbi = EXT2_SB(sb); 1273 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1274 1275 /* 1276 * Write quota structures to quota file, sync_blockdev() will write 1277 * them to disk later 1278 */ 1279 dquot_writeback_dquots(sb, -1); 1280 1281 spin_lock(&sbi->s_lock); 1282 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1283 ext2_debug("setting valid to 0\n"); 1284 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1285 } 1286 spin_unlock(&sbi->s_lock); 1287 ext2_sync_super(sb, es, wait); 1288 return 0; 1289} 1290 1291static int ext2_freeze(struct super_block *sb) 1292{ 1293 struct ext2_sb_info *sbi = EXT2_SB(sb); 1294 1295 /* 1296 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared 1297 * because we have unattached inodes and thus filesystem is not fully 1298 * consistent. 1299 */ 1300 if (atomic_long_read(&sb->s_remove_count)) { 1301 ext2_sync_fs(sb, 1); 1302 return 0; 1303 } 1304 /* Set EXT2_FS_VALID flag */ 1305 spin_lock(&sbi->s_lock); 1306 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); 1307 spin_unlock(&sbi->s_lock); 1308 ext2_sync_super(sb, sbi->s_es, 1); 1309 1310 return 0; 1311} 1312 1313static int ext2_unfreeze(struct super_block *sb) 1314{ 1315 /* Just write sb to clear EXT2_VALID_FS flag */ 1316 ext2_write_super(sb); 1317 1318 return 0; 1319} 1320 1321static void ext2_write_super(struct super_block *sb) 1322{ 1323 if (!sb_rdonly(sb)) 1324 ext2_sync_fs(sb, 1); 1325} 1326 1327static int ext2_remount (struct super_block * sb, int * flags, char * data) 1328{ 1329 struct ext2_sb_info * sbi = EXT2_SB(sb); 1330 struct ext2_super_block * es; 1331 struct ext2_mount_options new_opts; 1332 int err; 1333 1334 sync_filesystem(sb); 1335 1336 spin_lock(&sbi->s_lock); 1337 new_opts.s_mount_opt = sbi->s_mount_opt; 1338 new_opts.s_resuid = sbi->s_resuid; 1339 new_opts.s_resgid = sbi->s_resgid; 1340 spin_unlock(&sbi->s_lock); 1341 1342 if (!parse_options(data, sb, &new_opts)) 1343 return -EINVAL; 1344 1345 spin_lock(&sbi->s_lock); 1346 es = sbi->s_es; 1347 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) { 1348 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1349 "dax flag with busy inodes while remounting"); 1350 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX; 1351 } 1352 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) 1353 goto out_set; 1354 if (*flags & SB_RDONLY) { 1355 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1356 !(sbi->s_mount_state & EXT2_VALID_FS)) 1357 goto out_set; 1358 1359 /* 1360 * OK, we are remounting a valid rw partition rdonly, so set 1361 * the rdonly flag and then mark the partition as valid again. 1362 */ 1363 es->s_state = cpu_to_le16(sbi->s_mount_state); 1364 es->s_mtime = cpu_to_le32(ktime_get_real_seconds()); 1365 spin_unlock(&sbi->s_lock); 1366 1367 err = dquot_suspend(sb, -1); 1368 if (err < 0) 1369 return err; 1370 1371 ext2_sync_super(sb, es, 1); 1372 } else { 1373 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1374 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1375 if (ret) { 1376 spin_unlock(&sbi->s_lock); 1377 ext2_msg(sb, KERN_WARNING, 1378 "warning: couldn't remount RDWR because of " 1379 "unsupported optional features (%x).", 1380 le32_to_cpu(ret)); 1381 return -EROFS; 1382 } 1383 /* 1384 * Mounting a RDONLY partition read-write, so reread and 1385 * store the current valid flag. (It may have been changed 1386 * by e2fsck since we originally mounted the partition.) 1387 */ 1388 sbi->s_mount_state = le16_to_cpu(es->s_state); 1389 if (!ext2_setup_super (sb, es, 0)) 1390 sb->s_flags &= ~SB_RDONLY; 1391 spin_unlock(&sbi->s_lock); 1392 1393 ext2_write_super(sb); 1394 1395 dquot_resume(sb, -1); 1396 } 1397 1398 spin_lock(&sbi->s_lock); 1399out_set: 1400 sbi->s_mount_opt = new_opts.s_mount_opt; 1401 sbi->s_resuid = new_opts.s_resuid; 1402 sbi->s_resgid = new_opts.s_resgid; 1403 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | 1404 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0); 1405 spin_unlock(&sbi->s_lock); 1406 1407 return 0; 1408} 1409 1410static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1411{ 1412 struct super_block *sb = dentry->d_sb; 1413 struct ext2_sb_info *sbi = EXT2_SB(sb); 1414 struct ext2_super_block *es = sbi->s_es; 1415 1416 spin_lock(&sbi->s_lock); 1417 1418 if (test_opt (sb, MINIX_DF)) 1419 sbi->s_overhead_last = 0; 1420 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1421 unsigned long i, overhead = 0; 1422 smp_rmb(); 1423 1424 /* 1425 * Compute the overhead (FS structures). This is constant 1426 * for a given filesystem unless the number of block groups 1427 * changes so we cache the previous value until it does. 1428 */ 1429 1430 /* 1431 * All of the blocks before first_data_block are 1432 * overhead 1433 */ 1434 overhead = le32_to_cpu(es->s_first_data_block); 1435 1436 /* 1437 * Add the overhead attributed to the superblock and 1438 * block group descriptors. If the sparse superblocks 1439 * feature is turned on, then not all groups have this. 1440 */ 1441 for (i = 0; i < sbi->s_groups_count; i++) 1442 overhead += ext2_bg_has_super(sb, i) + 1443 ext2_bg_num_gdb(sb, i); 1444 1445 /* 1446 * Every block group has an inode bitmap, a block 1447 * bitmap, and an inode table. 1448 */ 1449 overhead += (sbi->s_groups_count * 1450 (2 + sbi->s_itb_per_group)); 1451 sbi->s_overhead_last = overhead; 1452 smp_wmb(); 1453 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1454 } 1455 1456 buf->f_type = EXT2_SUPER_MAGIC; 1457 buf->f_bsize = sb->s_blocksize; 1458 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1459 buf->f_bfree = ext2_count_free_blocks(sb); 1460 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1461 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1462 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1463 buf->f_bavail = 0; 1464 buf->f_files = le32_to_cpu(es->s_inodes_count); 1465 buf->f_ffree = ext2_count_free_inodes(sb); 1466 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1467 buf->f_namelen = EXT2_NAME_LEN; 1468 buf->f_fsid = uuid_to_fsid(es->s_uuid); 1469 spin_unlock(&sbi->s_lock); 1470 return 0; 1471} 1472 1473static struct dentry *ext2_mount(struct file_system_type *fs_type, 1474 int flags, const char *dev_name, void *data) 1475{ 1476 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1477} 1478 1479#ifdef CONFIG_QUOTA 1480 1481/* Read data from quotafile - avoid pagecache and such because we cannot afford 1482 * acquiring the locks... As quota files are never truncated and quota code 1483 * itself serializes the operations (and no one else should touch the files) 1484 * we don't have to be afraid of races */ 1485static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1486 size_t len, loff_t off) 1487{ 1488 struct inode *inode = sb_dqopt(sb)->files[type]; 1489 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1490 int err = 0; 1491 int offset = off & (sb->s_blocksize - 1); 1492 int tocopy; 1493 size_t toread; 1494 struct buffer_head tmp_bh; 1495 struct buffer_head *bh; 1496 loff_t i_size = i_size_read(inode); 1497 1498 if (off > i_size) 1499 return 0; 1500 if (off+len > i_size) 1501 len = i_size-off; 1502 toread = len; 1503 while (toread > 0) { 1504 tocopy = min_t(size_t, sb->s_blocksize - offset, toread); 1505 1506 tmp_bh.b_state = 0; 1507 tmp_bh.b_size = sb->s_blocksize; 1508 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1509 if (err < 0) 1510 return err; 1511 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1512 memset(data, 0, tocopy); 1513 else { 1514 bh = sb_bread(sb, tmp_bh.b_blocknr); 1515 if (!bh) 1516 return -EIO; 1517 memcpy(data, bh->b_data+offset, tocopy); 1518 brelse(bh); 1519 } 1520 offset = 0; 1521 toread -= tocopy; 1522 data += tocopy; 1523 blk++; 1524 } 1525 return len; 1526} 1527 1528/* Write to quotafile */ 1529static ssize_t ext2_quota_write(struct super_block *sb, int type, 1530 const char *data, size_t len, loff_t off) 1531{ 1532 struct inode *inode = sb_dqopt(sb)->files[type]; 1533 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1534 int err = 0; 1535 int offset = off & (sb->s_blocksize - 1); 1536 int tocopy; 1537 size_t towrite = len; 1538 struct buffer_head tmp_bh; 1539 struct buffer_head *bh; 1540 1541 while (towrite > 0) { 1542 tocopy = min_t(size_t, sb->s_blocksize - offset, towrite); 1543 1544 tmp_bh.b_state = 0; 1545 tmp_bh.b_size = sb->s_blocksize; 1546 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1547 if (err < 0) 1548 goto out; 1549 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1550 bh = sb_bread(sb, tmp_bh.b_blocknr); 1551 else 1552 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1553 if (unlikely(!bh)) { 1554 err = -EIO; 1555 goto out; 1556 } 1557 lock_buffer(bh); 1558 memcpy(bh->b_data+offset, data, tocopy); 1559 flush_dcache_page(bh->b_page); 1560 set_buffer_uptodate(bh); 1561 mark_buffer_dirty(bh); 1562 unlock_buffer(bh); 1563 brelse(bh); 1564 offset = 0; 1565 towrite -= tocopy; 1566 data += tocopy; 1567 blk++; 1568 } 1569out: 1570 if (len == towrite) 1571 return err; 1572 if (inode->i_size < off+len-towrite) 1573 i_size_write(inode, off+len-towrite); 1574 inode_inc_iversion(inode); 1575 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); 1576 mark_inode_dirty(inode); 1577 return len - towrite; 1578} 1579 1580static int ext2_quota_on(struct super_block *sb, int type, int format_id, 1581 const struct path *path) 1582{ 1583 int err; 1584 struct inode *inode; 1585 1586 err = dquot_quota_on(sb, type, format_id, path); 1587 if (err) 1588 return err; 1589 1590 inode = d_inode(path->dentry); 1591 inode_lock(inode); 1592 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL; 1593 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE, 1594 S_NOATIME | S_IMMUTABLE); 1595 inode_unlock(inode); 1596 mark_inode_dirty(inode); 1597 1598 return 0; 1599} 1600 1601static int ext2_quota_off(struct super_block *sb, int type) 1602{ 1603 struct inode *inode = sb_dqopt(sb)->files[type]; 1604 int err; 1605 1606 if (!inode || !igrab(inode)) 1607 goto out; 1608 1609 err = dquot_quota_off(sb, type); 1610 if (err) 1611 goto out_put; 1612 1613 inode_lock(inode); 1614 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL); 1615 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE); 1616 inode_unlock(inode); 1617 mark_inode_dirty(inode); 1618out_put: 1619 iput(inode); 1620 return err; 1621out: 1622 return dquot_quota_off(sb, type); 1623} 1624 1625#endif 1626 1627static struct file_system_type ext2_fs_type = { 1628 .owner = THIS_MODULE, 1629 .name = "ext2", 1630 .mount = ext2_mount, 1631 .kill_sb = kill_block_super, 1632 .fs_flags = FS_REQUIRES_DEV, 1633}; 1634MODULE_ALIAS_FS("ext2"); 1635 1636static int __init init_ext2_fs(void) 1637{ 1638 int err; 1639 1640 err = init_inodecache(); 1641 if (err) 1642 return err; 1643 err = register_filesystem(&ext2_fs_type); 1644 if (err) 1645 goto out; 1646 return 0; 1647out: 1648 destroy_inodecache(); 1649 return err; 1650} 1651 1652static void __exit exit_ext2_fs(void) 1653{ 1654 unregister_filesystem(&ext2_fs_type); 1655 destroy_inodecache(); 1656} 1657 1658MODULE_AUTHOR("Remy Card and others"); 1659MODULE_DESCRIPTION("Second Extended Filesystem"); 1660MODULE_LICENSE("GPL"); 1661module_init(init_ext2_fs) 1662module_exit(exit_ext2_fs) 1663