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 = kmem_cache_alloc(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 #ifdef CONFIG_FS_DAX 210 init_rwsem(&ei->dax_sem); 211 #endif 212 inode_init_once(&ei->vfs_inode); 213 } 214 215 static int __init init_inodecache(void) 216 { 217 ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache", 218 sizeof(struct ext2_inode_info), 0, 219 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD| 220 SLAB_ACCOUNT), 221 offsetof(struct ext2_inode_info, i_data), 222 sizeof_field(struct ext2_inode_info, i_data), 223 init_once); 224 if (ext2_inode_cachep == NULL) 225 return -ENOMEM; 226 return 0; 227 } 228 229 static void destroy_inodecache(void) 230 { 231 /* 232 * Make sure all delayed rcu free inodes are flushed before we 233 * destroy cache. 234 */ 235 rcu_barrier(); 236 kmem_cache_destroy(ext2_inode_cachep); 237 } 238 239 static int ext2_show_options(struct seq_file *seq, struct dentry *root) 240 { 241 struct super_block *sb = root->d_sb; 242 struct ext2_sb_info *sbi = EXT2_SB(sb); 243 struct ext2_super_block *es = sbi->s_es; 244 unsigned long def_mount_opts; 245 246 spin_lock(&sbi->s_lock); 247 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 248 249 if (sbi->s_sb_block != 1) 250 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 251 if (test_opt(sb, MINIX_DF)) 252 seq_puts(seq, ",minixdf"); 253 if (test_opt(sb, GRPID)) 254 seq_puts(seq, ",grpid"); 255 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 256 seq_puts(seq, ",nogrpid"); 257 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) || 258 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 259 seq_printf(seq, ",resuid=%u", 260 from_kuid_munged(&init_user_ns, sbi->s_resuid)); 261 } 262 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) || 263 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 264 seq_printf(seq, ",resgid=%u", 265 from_kgid_munged(&init_user_ns, sbi->s_resgid)); 266 } 267 if (test_opt(sb, ERRORS_RO)) { 268 int def_errors = le16_to_cpu(es->s_errors); 269 270 if (def_errors == EXT2_ERRORS_PANIC || 271 def_errors == EXT2_ERRORS_CONTINUE) { 272 seq_puts(seq, ",errors=remount-ro"); 273 } 274 } 275 if (test_opt(sb, ERRORS_CONT)) 276 seq_puts(seq, ",errors=continue"); 277 if (test_opt(sb, ERRORS_PANIC)) 278 seq_puts(seq, ",errors=panic"); 279 if (test_opt(sb, NO_UID32)) 280 seq_puts(seq, ",nouid32"); 281 if (test_opt(sb, DEBUG)) 282 seq_puts(seq, ",debug"); 283 if (test_opt(sb, OLDALLOC)) 284 seq_puts(seq, ",oldalloc"); 285 286 #ifdef CONFIG_EXT2_FS_XATTR 287 if (test_opt(sb, XATTR_USER)) 288 seq_puts(seq, ",user_xattr"); 289 if (!test_opt(sb, XATTR_USER) && 290 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 291 seq_puts(seq, ",nouser_xattr"); 292 } 293 #endif 294 295 #ifdef CONFIG_EXT2_FS_POSIX_ACL 296 if (test_opt(sb, POSIX_ACL)) 297 seq_puts(seq, ",acl"); 298 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 299 seq_puts(seq, ",noacl"); 300 #endif 301 302 if (test_opt(sb, NOBH)) 303 seq_puts(seq, ",nobh"); 304 305 if (test_opt(sb, USRQUOTA)) 306 seq_puts(seq, ",usrquota"); 307 308 if (test_opt(sb, GRPQUOTA)) 309 seq_puts(seq, ",grpquota"); 310 311 if (test_opt(sb, XIP)) 312 seq_puts(seq, ",xip"); 313 314 if (test_opt(sb, DAX)) 315 seq_puts(seq, ",dax"); 316 317 if (!test_opt(sb, RESERVATION)) 318 seq_puts(seq, ",noreservation"); 319 320 spin_unlock(&sbi->s_lock); 321 return 0; 322 } 323 324 #ifdef CONFIG_QUOTA 325 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 326 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 327 static int ext2_quota_on(struct super_block *sb, int type, int format_id, 328 const struct path *path); 329 static struct dquot **ext2_get_dquots(struct inode *inode) 330 { 331 return EXT2_I(inode)->i_dquot; 332 } 333 334 static const struct quotactl_ops ext2_quotactl_ops = { 335 .quota_on = ext2_quota_on, 336 .quota_off = ext2_quota_off, 337 .quota_sync = dquot_quota_sync, 338 .get_state = dquot_get_state, 339 .set_info = dquot_set_dqinfo, 340 .get_dqblk = dquot_get_dqblk, 341 .set_dqblk = dquot_set_dqblk, 342 .get_nextdqblk = dquot_get_next_dqblk, 343 }; 344 #endif 345 346 static const struct super_operations ext2_sops = { 347 .alloc_inode = ext2_alloc_inode, 348 .free_inode = ext2_free_in_core_inode, 349 .write_inode = ext2_write_inode, 350 .evict_inode = ext2_evict_inode, 351 .put_super = ext2_put_super, 352 .sync_fs = ext2_sync_fs, 353 .freeze_fs = ext2_freeze, 354 .unfreeze_fs = ext2_unfreeze, 355 .statfs = ext2_statfs, 356 .remount_fs = ext2_remount, 357 .show_options = ext2_show_options, 358 #ifdef CONFIG_QUOTA 359 .quota_read = ext2_quota_read, 360 .quota_write = ext2_quota_write, 361 .get_dquots = ext2_get_dquots, 362 #endif 363 }; 364 365 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 366 u64 ino, u32 generation) 367 { 368 struct inode *inode; 369 370 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 371 return ERR_PTR(-ESTALE); 372 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 373 return ERR_PTR(-ESTALE); 374 375 /* 376 * ext2_iget isn't quite right if the inode is currently unallocated! 377 * However ext2_iget currently does appropriate checks to handle stale 378 * inodes so everything is OK. 379 */ 380 inode = ext2_iget(sb, ino); 381 if (IS_ERR(inode)) 382 return ERR_CAST(inode); 383 if (generation && inode->i_generation != generation) { 384 /* we didn't find the right inode.. */ 385 iput(inode); 386 return ERR_PTR(-ESTALE); 387 } 388 return inode; 389 } 390 391 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 392 int fh_len, int fh_type) 393 { 394 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 395 ext2_nfs_get_inode); 396 } 397 398 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 399 int fh_len, int fh_type) 400 { 401 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 402 ext2_nfs_get_inode); 403 } 404 405 static const struct export_operations ext2_export_ops = { 406 .fh_to_dentry = ext2_fh_to_dentry, 407 .fh_to_parent = ext2_fh_to_parent, 408 .get_parent = ext2_get_parent, 409 }; 410 411 static unsigned long get_sb_block(void **data) 412 { 413 unsigned long sb_block; 414 char *options = (char *) *data; 415 416 if (!options || strncmp(options, "sb=", 3) != 0) 417 return 1; /* Default location */ 418 options += 3; 419 sb_block = simple_strtoul(options, &options, 0); 420 if (*options && *options != ',') { 421 printk("EXT2-fs: Invalid sb specification: %s\n", 422 (char *) *data); 423 return 1; 424 } 425 if (*options == ',') 426 options++; 427 *data = (void *) options; 428 return sb_block; 429 } 430 431 enum { 432 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 433 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 434 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 435 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 436 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota, 437 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 438 }; 439 440 static const match_table_t tokens = { 441 {Opt_bsd_df, "bsddf"}, 442 {Opt_minix_df, "minixdf"}, 443 {Opt_grpid, "grpid"}, 444 {Opt_grpid, "bsdgroups"}, 445 {Opt_nogrpid, "nogrpid"}, 446 {Opt_nogrpid, "sysvgroups"}, 447 {Opt_resgid, "resgid=%u"}, 448 {Opt_resuid, "resuid=%u"}, 449 {Opt_sb, "sb=%u"}, 450 {Opt_err_cont, "errors=continue"}, 451 {Opt_err_panic, "errors=panic"}, 452 {Opt_err_ro, "errors=remount-ro"}, 453 {Opt_nouid32, "nouid32"}, 454 {Opt_nocheck, "check=none"}, 455 {Opt_nocheck, "nocheck"}, 456 {Opt_debug, "debug"}, 457 {Opt_oldalloc, "oldalloc"}, 458 {Opt_orlov, "orlov"}, 459 {Opt_nobh, "nobh"}, 460 {Opt_user_xattr, "user_xattr"}, 461 {Opt_nouser_xattr, "nouser_xattr"}, 462 {Opt_acl, "acl"}, 463 {Opt_noacl, "noacl"}, 464 {Opt_xip, "xip"}, 465 {Opt_dax, "dax"}, 466 {Opt_grpquota, "grpquota"}, 467 {Opt_ignore, "noquota"}, 468 {Opt_quota, "quota"}, 469 {Opt_usrquota, "usrquota"}, 470 {Opt_reservation, "reservation"}, 471 {Opt_noreservation, "noreservation"}, 472 {Opt_err, NULL} 473 }; 474 475 static int parse_options(char *options, struct super_block *sb, 476 struct ext2_mount_options *opts) 477 { 478 char *p; 479 substring_t args[MAX_OPT_ARGS]; 480 int option; 481 kuid_t uid; 482 kgid_t gid; 483 484 if (!options) 485 return 1; 486 487 while ((p = strsep (&options, ",")) != NULL) { 488 int token; 489 if (!*p) 490 continue; 491 492 token = match_token(p, tokens, args); 493 switch (token) { 494 case Opt_bsd_df: 495 clear_opt (opts->s_mount_opt, MINIX_DF); 496 break; 497 case Opt_minix_df: 498 set_opt (opts->s_mount_opt, MINIX_DF); 499 break; 500 case Opt_grpid: 501 set_opt (opts->s_mount_opt, GRPID); 502 break; 503 case Opt_nogrpid: 504 clear_opt (opts->s_mount_opt, GRPID); 505 break; 506 case Opt_resuid: 507 if (match_int(&args[0], &option)) 508 return 0; 509 uid = make_kuid(current_user_ns(), option); 510 if (!uid_valid(uid)) { 511 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option); 512 return 0; 513 514 } 515 opts->s_resuid = uid; 516 break; 517 case Opt_resgid: 518 if (match_int(&args[0], &option)) 519 return 0; 520 gid = make_kgid(current_user_ns(), option); 521 if (!gid_valid(gid)) { 522 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option); 523 return 0; 524 } 525 opts->s_resgid = gid; 526 break; 527 case Opt_sb: 528 /* handled by get_sb_block() instead of here */ 529 /* *sb_block = match_int(&args[0]); */ 530 break; 531 case Opt_err_panic: 532 clear_opt (opts->s_mount_opt, ERRORS_CONT); 533 clear_opt (opts->s_mount_opt, ERRORS_RO); 534 set_opt (opts->s_mount_opt, ERRORS_PANIC); 535 break; 536 case Opt_err_ro: 537 clear_opt (opts->s_mount_opt, ERRORS_CONT); 538 clear_opt (opts->s_mount_opt, ERRORS_PANIC); 539 set_opt (opts->s_mount_opt, ERRORS_RO); 540 break; 541 case Opt_err_cont: 542 clear_opt (opts->s_mount_opt, ERRORS_RO); 543 clear_opt (opts->s_mount_opt, ERRORS_PANIC); 544 set_opt (opts->s_mount_opt, ERRORS_CONT); 545 break; 546 case Opt_nouid32: 547 set_opt (opts->s_mount_opt, NO_UID32); 548 break; 549 case Opt_nocheck: 550 ext2_msg(sb, KERN_WARNING, 551 "Option nocheck/check=none is deprecated and" 552 " will be removed in June 2020."); 553 clear_opt (opts->s_mount_opt, CHECK); 554 break; 555 case Opt_debug: 556 set_opt (opts->s_mount_opt, DEBUG); 557 break; 558 case Opt_oldalloc: 559 set_opt (opts->s_mount_opt, OLDALLOC); 560 break; 561 case Opt_orlov: 562 clear_opt (opts->s_mount_opt, OLDALLOC); 563 break; 564 case Opt_nobh: 565 set_opt (opts->s_mount_opt, NOBH); 566 break; 567 #ifdef CONFIG_EXT2_FS_XATTR 568 case Opt_user_xattr: 569 set_opt (opts->s_mount_opt, XATTR_USER); 570 break; 571 case Opt_nouser_xattr: 572 clear_opt (opts->s_mount_opt, XATTR_USER); 573 break; 574 #else 575 case Opt_user_xattr: 576 case Opt_nouser_xattr: 577 ext2_msg(sb, KERN_INFO, "(no)user_xattr options" 578 "not supported"); 579 break; 580 #endif 581 #ifdef CONFIG_EXT2_FS_POSIX_ACL 582 case Opt_acl: 583 set_opt(opts->s_mount_opt, POSIX_ACL); 584 break; 585 case Opt_noacl: 586 clear_opt(opts->s_mount_opt, POSIX_ACL); 587 break; 588 #else 589 case Opt_acl: 590 case Opt_noacl: 591 ext2_msg(sb, KERN_INFO, 592 "(no)acl options not supported"); 593 break; 594 #endif 595 case Opt_xip: 596 ext2_msg(sb, KERN_INFO, "use dax instead of xip"); 597 set_opt(opts->s_mount_opt, XIP); 598 /* Fall through */ 599 case Opt_dax: 600 #ifdef CONFIG_FS_DAX 601 ext2_msg(sb, KERN_WARNING, 602 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk"); 603 set_opt(opts->s_mount_opt, DAX); 604 #else 605 ext2_msg(sb, KERN_INFO, "dax option not supported"); 606 #endif 607 break; 608 609 #if defined(CONFIG_QUOTA) 610 case Opt_quota: 611 case Opt_usrquota: 612 set_opt(opts->s_mount_opt, USRQUOTA); 613 break; 614 615 case Opt_grpquota: 616 set_opt(opts->s_mount_opt, GRPQUOTA); 617 break; 618 #else 619 case Opt_quota: 620 case Opt_usrquota: 621 case Opt_grpquota: 622 ext2_msg(sb, KERN_INFO, 623 "quota operations not supported"); 624 break; 625 #endif 626 627 case Opt_reservation: 628 set_opt(opts->s_mount_opt, RESERVATION); 629 ext2_msg(sb, KERN_INFO, "reservations ON"); 630 break; 631 case Opt_noreservation: 632 clear_opt(opts->s_mount_opt, RESERVATION); 633 ext2_msg(sb, KERN_INFO, "reservations OFF"); 634 break; 635 case Opt_ignore: 636 break; 637 default: 638 return 0; 639 } 640 } 641 return 1; 642 } 643 644 static int ext2_setup_super (struct super_block * sb, 645 struct ext2_super_block * es, 646 int read_only) 647 { 648 int res = 0; 649 struct ext2_sb_info *sbi = EXT2_SB(sb); 650 651 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 652 ext2_msg(sb, KERN_ERR, 653 "error: revision level too high, " 654 "forcing read-only mode"); 655 res = SB_RDONLY; 656 } 657 if (read_only) 658 return res; 659 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 660 ext2_msg(sb, KERN_WARNING, 661 "warning: mounting unchecked fs, " 662 "running e2fsck is recommended"); 663 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 664 ext2_msg(sb, KERN_WARNING, 665 "warning: mounting fs with errors, " 666 "running e2fsck is recommended"); 667 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 668 le16_to_cpu(es->s_mnt_count) >= 669 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 670 ext2_msg(sb, KERN_WARNING, 671 "warning: maximal mount count reached, " 672 "running e2fsck is recommended"); 673 else if (le32_to_cpu(es->s_checkinterval) && 674 (le32_to_cpu(es->s_lastcheck) + 675 le32_to_cpu(es->s_checkinterval) <= 676 ktime_get_real_seconds())) 677 ext2_msg(sb, KERN_WARNING, 678 "warning: checktime reached, " 679 "running e2fsck is recommended"); 680 if (!le16_to_cpu(es->s_max_mnt_count)) 681 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 682 le16_add_cpu(&es->s_mnt_count, 1); 683 if (test_opt (sb, DEBUG)) 684 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, " 685 "bpg=%lu, ipg=%lu, mo=%04lx]", 686 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 687 sbi->s_frag_size, 688 sbi->s_groups_count, 689 EXT2_BLOCKS_PER_GROUP(sb), 690 EXT2_INODES_PER_GROUP(sb), 691 sbi->s_mount_opt); 692 return res; 693 } 694 695 static int ext2_check_descriptors(struct super_block *sb) 696 { 697 int i; 698 struct ext2_sb_info *sbi = EXT2_SB(sb); 699 700 ext2_debug ("Checking group descriptors"); 701 702 for (i = 0; i < sbi->s_groups_count; i++) { 703 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 704 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 705 ext2_fsblk_t last_block = ext2_group_last_block_no(sb, i); 706 707 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 708 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 709 { 710 ext2_error (sb, "ext2_check_descriptors", 711 "Block bitmap for group %d" 712 " not in group (block %lu)!", 713 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 714 return 0; 715 } 716 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 717 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 718 { 719 ext2_error (sb, "ext2_check_descriptors", 720 "Inode bitmap for group %d" 721 " not in group (block %lu)!", 722 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 723 return 0; 724 } 725 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 726 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 727 last_block) 728 { 729 ext2_error (sb, "ext2_check_descriptors", 730 "Inode table for group %d" 731 " not in group (block %lu)!", 732 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 733 return 0; 734 } 735 } 736 return 1; 737 } 738 739 /* 740 * Maximal file size. There is a direct, and {,double-,triple-}indirect 741 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 742 * We need to be 1 filesystem block less than the 2^32 sector limit. 743 */ 744 static loff_t ext2_max_size(int bits) 745 { 746 loff_t res = EXT2_NDIR_BLOCKS; 747 int meta_blocks; 748 unsigned int upper_limit; 749 unsigned int ppb = 1 << (bits-2); 750 751 /* This is calculated to be the largest file size for a 752 * dense, file such that the total number of 753 * sectors in the file, including data and all indirect blocks, 754 * does not exceed 2^32 -1 755 * __u32 i_blocks representing the total number of 756 * 512 bytes blocks of the file 757 */ 758 upper_limit = (1LL << 32) - 1; 759 760 /* total blocks in file system block size */ 761 upper_limit >>= (bits - 9); 762 763 /* Compute how many blocks we can address by block tree */ 764 res += 1LL << (bits-2); 765 res += 1LL << (2*(bits-2)); 766 res += 1LL << (3*(bits-2)); 767 /* Does block tree limit file size? */ 768 if (res < upper_limit) 769 goto check_lfs; 770 771 res = upper_limit; 772 /* How many metadata blocks are needed for addressing upper_limit? */ 773 upper_limit -= EXT2_NDIR_BLOCKS; 774 /* indirect blocks */ 775 meta_blocks = 1; 776 upper_limit -= ppb; 777 /* double indirect blocks */ 778 if (upper_limit < ppb * ppb) { 779 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb); 780 res -= meta_blocks; 781 goto check_lfs; 782 } 783 meta_blocks += 1 + ppb; 784 upper_limit -= ppb * ppb; 785 /* tripple indirect blocks for the rest */ 786 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) + 787 DIV_ROUND_UP(upper_limit, ppb*ppb); 788 res -= meta_blocks; 789 check_lfs: 790 res <<= bits; 791 if (res > MAX_LFS_FILESIZE) 792 res = MAX_LFS_FILESIZE; 793 794 return res; 795 } 796 797 static unsigned long descriptor_loc(struct super_block *sb, 798 unsigned long logic_sb_block, 799 int nr) 800 { 801 struct ext2_sb_info *sbi = EXT2_SB(sb); 802 unsigned long bg, first_meta_bg; 803 804 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 805 806 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 807 nr < first_meta_bg) 808 return (logic_sb_block + nr + 1); 809 bg = sbi->s_desc_per_block * nr; 810 811 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg); 812 } 813 814 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 815 { 816 struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev); 817 struct buffer_head * bh; 818 struct ext2_sb_info * sbi; 819 struct ext2_super_block * es; 820 struct inode *root; 821 unsigned long block; 822 unsigned long sb_block = get_sb_block(&data); 823 unsigned long logic_sb_block; 824 unsigned long offset = 0; 825 unsigned long def_mount_opts; 826 long ret = -ENOMEM; 827 int blocksize = BLOCK_SIZE; 828 int db_count; 829 int i, j; 830 __le32 features; 831 int err; 832 struct ext2_mount_options opts; 833 834 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 835 if (!sbi) 836 goto failed; 837 838 sbi->s_blockgroup_lock = 839 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 840 if (!sbi->s_blockgroup_lock) { 841 kfree(sbi); 842 goto failed; 843 } 844 sb->s_fs_info = sbi; 845 sbi->s_sb_block = sb_block; 846 sbi->s_daxdev = dax_dev; 847 848 spin_lock_init(&sbi->s_lock); 849 ret = -EINVAL; 850 851 /* 852 * See what the current blocksize for the device is, and 853 * use that as the blocksize. Otherwise (or if the blocksize 854 * is smaller than the default) use the default. 855 * This is important for devices that have a hardware 856 * sectorsize that is larger than the default. 857 */ 858 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 859 if (!blocksize) { 860 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 861 goto failed_sbi; 862 } 863 864 /* 865 * If the superblock doesn't start on a hardware sector boundary, 866 * calculate the offset. 867 */ 868 if (blocksize != BLOCK_SIZE) { 869 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 870 offset = (sb_block*BLOCK_SIZE) % blocksize; 871 } else { 872 logic_sb_block = sb_block; 873 } 874 875 if (!(bh = sb_bread(sb, logic_sb_block))) { 876 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 877 goto failed_sbi; 878 } 879 /* 880 * Note: s_es must be initialized as soon as possible because 881 * some ext2 macro-instructions depend on its value 882 */ 883 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 884 sbi->s_es = es; 885 sb->s_magic = le16_to_cpu(es->s_magic); 886 887 if (sb->s_magic != EXT2_SUPER_MAGIC) 888 goto cantfind_ext2; 889 890 opts.s_mount_opt = 0; 891 /* Set defaults before we parse the mount options */ 892 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 893 if (def_mount_opts & EXT2_DEFM_DEBUG) 894 set_opt(opts.s_mount_opt, DEBUG); 895 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 896 set_opt(opts.s_mount_opt, GRPID); 897 if (def_mount_opts & EXT2_DEFM_UID16) 898 set_opt(opts.s_mount_opt, NO_UID32); 899 #ifdef CONFIG_EXT2_FS_XATTR 900 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 901 set_opt(opts.s_mount_opt, XATTR_USER); 902 #endif 903 #ifdef CONFIG_EXT2_FS_POSIX_ACL 904 if (def_mount_opts & EXT2_DEFM_ACL) 905 set_opt(opts.s_mount_opt, POSIX_ACL); 906 #endif 907 908 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 909 set_opt(opts.s_mount_opt, ERRORS_PANIC); 910 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 911 set_opt(opts.s_mount_opt, ERRORS_CONT); 912 else 913 set_opt(opts.s_mount_opt, ERRORS_RO); 914 915 opts.s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid)); 916 opts.s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid)); 917 918 set_opt(opts.s_mount_opt, RESERVATION); 919 920 if (!parse_options((char *) data, sb, &opts)) 921 goto failed_mount; 922 923 sbi->s_mount_opt = opts.s_mount_opt; 924 sbi->s_resuid = opts.s_resuid; 925 sbi->s_resgid = opts.s_resgid; 926 927 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | 928 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0); 929 sb->s_iflags |= SB_I_CGROUPWB; 930 931 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 932 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 933 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 934 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 935 ext2_msg(sb, KERN_WARNING, 936 "warning: feature flags set on rev 0 fs, " 937 "running e2fsck is recommended"); 938 /* 939 * Check feature flags regardless of the revision level, since we 940 * previously didn't change the revision level when setting the flags, 941 * so there is a chance incompat flags are set on a rev 0 filesystem. 942 */ 943 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 944 if (features) { 945 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 946 "unsupported optional features (%x)", 947 le32_to_cpu(features)); 948 goto failed_mount; 949 } 950 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 951 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 952 "unsupported optional features (%x)", 953 le32_to_cpu(features)); 954 goto failed_mount; 955 } 956 957 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 958 959 if (test_opt(sb, DAX)) { 960 if (!bdev_dax_supported(sb->s_bdev, blocksize)) { 961 ext2_msg(sb, KERN_ERR, 962 "DAX unsupported by block device. Turning off DAX."); 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_frag_size = EXT2_MIN_FRAG_SIZE << 1015 le32_to_cpu(es->s_log_frag_size); 1016 if (sbi->s_frag_size == 0) 1017 goto cantfind_ext2; 1018 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 1019 1020 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 1021 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 1022 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 1023 1024 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 1025 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 1026 goto cantfind_ext2; 1027 sbi->s_itb_per_group = sbi->s_inodes_per_group / 1028 sbi->s_inodes_per_block; 1029 sbi->s_desc_per_block = sb->s_blocksize / 1030 sizeof (struct ext2_group_desc); 1031 sbi->s_sbh = bh; 1032 sbi->s_mount_state = le16_to_cpu(es->s_state); 1033 sbi->s_addr_per_block_bits = 1034 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 1035 sbi->s_desc_per_block_bits = 1036 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 1037 1038 if (sb->s_magic != EXT2_SUPER_MAGIC) 1039 goto cantfind_ext2; 1040 1041 if (sb->s_blocksize != bh->b_size) { 1042 if (!silent) 1043 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 1044 goto failed_mount; 1045 } 1046 1047 if (sb->s_blocksize != sbi->s_frag_size) { 1048 ext2_msg(sb, KERN_ERR, 1049 "error: fragsize %lu != blocksize %lu" 1050 "(not supported yet)", 1051 sbi->s_frag_size, sb->s_blocksize); 1052 goto failed_mount; 1053 } 1054 1055 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 1056 ext2_msg(sb, KERN_ERR, 1057 "error: #blocks per group too big: %lu", 1058 sbi->s_blocks_per_group); 1059 goto failed_mount; 1060 } 1061 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 1062 ext2_msg(sb, KERN_ERR, 1063 "error: #fragments per group too big: %lu", 1064 sbi->s_frags_per_group); 1065 goto failed_mount; 1066 } 1067 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 1068 ext2_msg(sb, KERN_ERR, 1069 "error: #inodes per group too big: %lu", 1070 sbi->s_inodes_per_group); 1071 goto failed_mount; 1072 } 1073 1074 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 1075 goto cantfind_ext2; 1076 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1077 le32_to_cpu(es->s_first_data_block) - 1) 1078 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1079 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1080 EXT2_DESC_PER_BLOCK(sb); 1081 sbi->s_group_desc = kmalloc_array (db_count, 1082 sizeof(struct buffer_head *), 1083 GFP_KERNEL); 1084 if (sbi->s_group_desc == NULL) { 1085 ret = -ENOMEM; 1086 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1087 goto failed_mount; 1088 } 1089 bgl_lock_init(sbi->s_blockgroup_lock); 1090 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1091 if (!sbi->s_debts) { 1092 ret = -ENOMEM; 1093 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1094 goto failed_mount_group_desc; 1095 } 1096 for (i = 0; i < db_count; i++) { 1097 block = descriptor_loc(sb, logic_sb_block, i); 1098 sbi->s_group_desc[i] = sb_bread(sb, block); 1099 if (!sbi->s_group_desc[i]) { 1100 for (j = 0; j < i; j++) 1101 brelse (sbi->s_group_desc[j]); 1102 ext2_msg(sb, KERN_ERR, 1103 "error: unable to read group descriptors"); 1104 goto failed_mount_group_desc; 1105 } 1106 } 1107 if (!ext2_check_descriptors (sb)) { 1108 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1109 goto failed_mount2; 1110 } 1111 sbi->s_gdb_count = db_count; 1112 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1113 spin_lock_init(&sbi->s_next_gen_lock); 1114 1115 /* per fileystem reservation list head & lock */ 1116 spin_lock_init(&sbi->s_rsv_window_lock); 1117 sbi->s_rsv_window_root = RB_ROOT; 1118 /* 1119 * Add a single, static dummy reservation to the start of the 1120 * reservation window list --- it gives us a placeholder for 1121 * append-at-start-of-list which makes the allocation logic 1122 * _much_ simpler. 1123 */ 1124 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1125 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1126 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1127 sbi->s_rsv_window_head.rsv_goal_size = 0; 1128 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1129 1130 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1131 ext2_count_free_blocks(sb), GFP_KERNEL); 1132 if (!err) { 1133 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1134 ext2_count_free_inodes(sb), GFP_KERNEL); 1135 } 1136 if (!err) { 1137 err = percpu_counter_init(&sbi->s_dirs_counter, 1138 ext2_count_dirs(sb), GFP_KERNEL); 1139 } 1140 if (err) { 1141 ret = err; 1142 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1143 goto failed_mount3; 1144 } 1145 1146 #ifdef CONFIG_EXT2_FS_XATTR 1147 sbi->s_ea_block_cache = ext2_xattr_create_cache(); 1148 if (!sbi->s_ea_block_cache) { 1149 ret = -ENOMEM; 1150 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache"); 1151 goto failed_mount3; 1152 } 1153 #endif 1154 /* 1155 * set up enough so that it can read an inode 1156 */ 1157 sb->s_op = &ext2_sops; 1158 sb->s_export_op = &ext2_export_ops; 1159 sb->s_xattr = ext2_xattr_handlers; 1160 1161 #ifdef CONFIG_QUOTA 1162 sb->dq_op = &dquot_operations; 1163 sb->s_qcop = &ext2_quotactl_ops; 1164 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP; 1165 #endif 1166 1167 root = ext2_iget(sb, EXT2_ROOT_INO); 1168 if (IS_ERR(root)) { 1169 ret = PTR_ERR(root); 1170 goto failed_mount3; 1171 } 1172 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1173 iput(root); 1174 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1175 goto failed_mount3; 1176 } 1177 1178 sb->s_root = d_make_root(root); 1179 if (!sb->s_root) { 1180 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1181 ret = -ENOMEM; 1182 goto failed_mount3; 1183 } 1184 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1185 ext2_msg(sb, KERN_WARNING, 1186 "warning: mounting ext3 filesystem as ext2"); 1187 if (ext2_setup_super (sb, es, sb_rdonly(sb))) 1188 sb->s_flags |= SB_RDONLY; 1189 ext2_write_super(sb); 1190 return 0; 1191 1192 cantfind_ext2: 1193 if (!silent) 1194 ext2_msg(sb, KERN_ERR, 1195 "error: can't find an ext2 filesystem on dev %s.", 1196 sb->s_id); 1197 goto failed_mount; 1198 failed_mount3: 1199 ext2_xattr_destroy_cache(sbi->s_ea_block_cache); 1200 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1201 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1202 percpu_counter_destroy(&sbi->s_dirs_counter); 1203 failed_mount2: 1204 for (i = 0; i < db_count; i++) 1205 brelse(sbi->s_group_desc[i]); 1206 failed_mount_group_desc: 1207 kfree(sbi->s_group_desc); 1208 kfree(sbi->s_debts); 1209 failed_mount: 1210 brelse(bh); 1211 failed_sbi: 1212 sb->s_fs_info = NULL; 1213 kfree(sbi->s_blockgroup_lock); 1214 kfree(sbi); 1215 failed: 1216 fs_put_dax(dax_dev); 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 u64 fsid; 1411 1412 spin_lock(&sbi->s_lock); 1413 1414 if (test_opt (sb, MINIX_DF)) 1415 sbi->s_overhead_last = 0; 1416 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1417 unsigned long i, overhead = 0; 1418 smp_rmb(); 1419 1420 /* 1421 * Compute the overhead (FS structures). This is constant 1422 * for a given filesystem unless the number of block groups 1423 * changes so we cache the previous value until it does. 1424 */ 1425 1426 /* 1427 * All of the blocks before first_data_block are 1428 * overhead 1429 */ 1430 overhead = le32_to_cpu(es->s_first_data_block); 1431 1432 /* 1433 * Add the overhead attributed to the superblock and 1434 * block group descriptors. If the sparse superblocks 1435 * feature is turned on, then not all groups have this. 1436 */ 1437 for (i = 0; i < sbi->s_groups_count; i++) 1438 overhead += ext2_bg_has_super(sb, i) + 1439 ext2_bg_num_gdb(sb, i); 1440 1441 /* 1442 * Every block group has an inode bitmap, a block 1443 * bitmap, and an inode table. 1444 */ 1445 overhead += (sbi->s_groups_count * 1446 (2 + sbi->s_itb_per_group)); 1447 sbi->s_overhead_last = overhead; 1448 smp_wmb(); 1449 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1450 } 1451 1452 buf->f_type = EXT2_SUPER_MAGIC; 1453 buf->f_bsize = sb->s_blocksize; 1454 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1455 buf->f_bfree = ext2_count_free_blocks(sb); 1456 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1457 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1458 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1459 buf->f_bavail = 0; 1460 buf->f_files = le32_to_cpu(es->s_inodes_count); 1461 buf->f_ffree = ext2_count_free_inodes(sb); 1462 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1463 buf->f_namelen = EXT2_NAME_LEN; 1464 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1465 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1466 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1467 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1468 spin_unlock(&sbi->s_lock); 1469 return 0; 1470 } 1471 1472 static struct dentry *ext2_mount(struct file_system_type *fs_type, 1473 int flags, const char *dev_name, void *data) 1474 { 1475 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1476 } 1477 1478 #ifdef CONFIG_QUOTA 1479 1480 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1481 * acquiring the locks... As quota files are never truncated and quota code 1482 * itself serializes the operations (and no one else should touch the files) 1483 * we don't have to be afraid of races */ 1484 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1485 size_t len, loff_t off) 1486 { 1487 struct inode *inode = sb_dqopt(sb)->files[type]; 1488 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1489 int err = 0; 1490 int offset = off & (sb->s_blocksize - 1); 1491 int tocopy; 1492 size_t toread; 1493 struct buffer_head tmp_bh; 1494 struct buffer_head *bh; 1495 loff_t i_size = i_size_read(inode); 1496 1497 if (off > i_size) 1498 return 0; 1499 if (off+len > i_size) 1500 len = i_size-off; 1501 toread = len; 1502 while (toread > 0) { 1503 tocopy = sb->s_blocksize - offset < toread ? 1504 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 */ 1529 static 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 = sb->s_blocksize - offset < towrite ? 1543 sb->s_blocksize - offset : towrite; 1544 1545 tmp_bh.b_state = 0; 1546 tmp_bh.b_size = sb->s_blocksize; 1547 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1548 if (err < 0) 1549 goto out; 1550 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1551 bh = sb_bread(sb, tmp_bh.b_blocknr); 1552 else 1553 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1554 if (unlikely(!bh)) { 1555 err = -EIO; 1556 goto out; 1557 } 1558 lock_buffer(bh); 1559 memcpy(bh->b_data+offset, data, tocopy); 1560 flush_dcache_page(bh->b_page); 1561 set_buffer_uptodate(bh); 1562 mark_buffer_dirty(bh); 1563 unlock_buffer(bh); 1564 brelse(bh); 1565 offset = 0; 1566 towrite -= tocopy; 1567 data += tocopy; 1568 blk++; 1569 } 1570 out: 1571 if (len == towrite) 1572 return err; 1573 if (inode->i_size < off+len-towrite) 1574 i_size_write(inode, off+len-towrite); 1575 inode_inc_iversion(inode); 1576 inode->i_mtime = inode->i_ctime = current_time(inode); 1577 mark_inode_dirty(inode); 1578 return len - towrite; 1579 } 1580 1581 static int ext2_quota_on(struct super_block *sb, int type, int format_id, 1582 const struct path *path) 1583 { 1584 int err; 1585 struct inode *inode; 1586 1587 err = dquot_quota_on(sb, type, format_id, path); 1588 if (err) 1589 return err; 1590 1591 inode = d_inode(path->dentry); 1592 inode_lock(inode); 1593 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL; 1594 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE, 1595 S_NOATIME | S_IMMUTABLE); 1596 inode_unlock(inode); 1597 mark_inode_dirty(inode); 1598 1599 return 0; 1600 } 1601 1602 static int ext2_quota_off(struct super_block *sb, int type) 1603 { 1604 struct inode *inode = sb_dqopt(sb)->files[type]; 1605 int err; 1606 1607 if (!inode || !igrab(inode)) 1608 goto out; 1609 1610 err = dquot_quota_off(sb, type); 1611 if (err) 1612 goto out_put; 1613 1614 inode_lock(inode); 1615 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL); 1616 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE); 1617 inode_unlock(inode); 1618 mark_inode_dirty(inode); 1619 out_put: 1620 iput(inode); 1621 return err; 1622 out: 1623 return dquot_quota_off(sb, type); 1624 } 1625 1626 #endif 1627 1628 static struct file_system_type ext2_fs_type = { 1629 .owner = THIS_MODULE, 1630 .name = "ext2", 1631 .mount = ext2_mount, 1632 .kill_sb = kill_block_super, 1633 .fs_flags = FS_REQUIRES_DEV, 1634 }; 1635 MODULE_ALIAS_FS("ext2"); 1636 1637 static int __init init_ext2_fs(void) 1638 { 1639 int err; 1640 1641 err = init_inodecache(); 1642 if (err) 1643 return err; 1644 err = register_filesystem(&ext2_fs_type); 1645 if (err) 1646 goto out; 1647 return 0; 1648 out: 1649 destroy_inodecache(); 1650 return err; 1651 } 1652 1653 static void __exit exit_ext2_fs(void) 1654 { 1655 unregister_filesystem(&ext2_fs_type); 1656 destroy_inodecache(); 1657 } 1658 1659 MODULE_AUTHOR("Remy Card and others"); 1660 MODULE_DESCRIPTION("Second Extended Filesystem"); 1661 MODULE_LICENSE("GPL"); 1662 module_init(init_ext2_fs) 1663 module_exit(exit_ext2_fs) 1664