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 if (sbi->s_group_desc[i]) 166 brelse (sbi->s_group_desc[i]); 167 kfree(sbi->s_group_desc); 168 kfree(sbi->s_debts); 169 percpu_counter_destroy(&sbi->s_freeblocks_counter); 170 percpu_counter_destroy(&sbi->s_freeinodes_counter); 171 percpu_counter_destroy(&sbi->s_dirs_counter); 172 brelse (sbi->s_sbh); 173 sb->s_fs_info = NULL; 174 kfree(sbi->s_blockgroup_lock); 175 fs_put_dax(sbi->s_daxdev); 176 kfree(sbi); 177 } 178 179 static struct kmem_cache * ext2_inode_cachep; 180 181 static struct inode *ext2_alloc_inode(struct super_block *sb) 182 { 183 struct ext2_inode_info *ei; 184 ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL); 185 if (!ei) 186 return NULL; 187 ei->i_block_alloc_info = NULL; 188 inode_set_iversion(&ei->vfs_inode, 1); 189 #ifdef CONFIG_QUOTA 190 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot)); 191 #endif 192 193 return &ei->vfs_inode; 194 } 195 196 static void ext2_free_in_core_inode(struct inode *inode) 197 { 198 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 199 } 200 201 static void init_once(void *foo) 202 { 203 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 204 205 rwlock_init(&ei->i_meta_lock); 206 #ifdef CONFIG_EXT2_FS_XATTR 207 init_rwsem(&ei->xattr_sem); 208 #endif 209 mutex_init(&ei->truncate_mutex); 210 #ifdef CONFIG_FS_DAX 211 init_rwsem(&ei->dax_sem); 212 #endif 213 inode_init_once(&ei->vfs_inode); 214 } 215 216 static int __init init_inodecache(void) 217 { 218 ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache", 219 sizeof(struct ext2_inode_info), 0, 220 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD| 221 SLAB_ACCOUNT), 222 offsetof(struct ext2_inode_info, i_data), 223 sizeof_field(struct ext2_inode_info, i_data), 224 init_once); 225 if (ext2_inode_cachep == NULL) 226 return -ENOMEM; 227 return 0; 228 } 229 230 static void destroy_inodecache(void) 231 { 232 /* 233 * Make sure all delayed rcu free inodes are flushed before we 234 * destroy cache. 235 */ 236 rcu_barrier(); 237 kmem_cache_destroy(ext2_inode_cachep); 238 } 239 240 static int ext2_show_options(struct seq_file *seq, struct dentry *root) 241 { 242 struct super_block *sb = root->d_sb; 243 struct ext2_sb_info *sbi = EXT2_SB(sb); 244 struct ext2_super_block *es = sbi->s_es; 245 unsigned long def_mount_opts; 246 247 spin_lock(&sbi->s_lock); 248 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 249 250 if (sbi->s_sb_block != 1) 251 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 252 if (test_opt(sb, MINIX_DF)) 253 seq_puts(seq, ",minixdf"); 254 if (test_opt(sb, GRPID)) 255 seq_puts(seq, ",grpid"); 256 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 257 seq_puts(seq, ",nogrpid"); 258 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) || 259 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 260 seq_printf(seq, ",resuid=%u", 261 from_kuid_munged(&init_user_ns, sbi->s_resuid)); 262 } 263 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) || 264 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 265 seq_printf(seq, ",resgid=%u", 266 from_kgid_munged(&init_user_ns, sbi->s_resgid)); 267 } 268 if (test_opt(sb, ERRORS_RO)) { 269 int def_errors = le16_to_cpu(es->s_errors); 270 271 if (def_errors == EXT2_ERRORS_PANIC || 272 def_errors == EXT2_ERRORS_CONTINUE) { 273 seq_puts(seq, ",errors=remount-ro"); 274 } 275 } 276 if (test_opt(sb, ERRORS_CONT)) 277 seq_puts(seq, ",errors=continue"); 278 if (test_opt(sb, ERRORS_PANIC)) 279 seq_puts(seq, ",errors=panic"); 280 if (test_opt(sb, NO_UID32)) 281 seq_puts(seq, ",nouid32"); 282 if (test_opt(sb, DEBUG)) 283 seq_puts(seq, ",debug"); 284 if (test_opt(sb, OLDALLOC)) 285 seq_puts(seq, ",oldalloc"); 286 287 #ifdef CONFIG_EXT2_FS_XATTR 288 if (test_opt(sb, XATTR_USER)) 289 seq_puts(seq, ",user_xattr"); 290 if (!test_opt(sb, XATTR_USER) && 291 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 292 seq_puts(seq, ",nouser_xattr"); 293 } 294 #endif 295 296 #ifdef CONFIG_EXT2_FS_POSIX_ACL 297 if (test_opt(sb, POSIX_ACL)) 298 seq_puts(seq, ",acl"); 299 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 300 seq_puts(seq, ",noacl"); 301 #endif 302 303 if (test_opt(sb, NOBH)) 304 seq_puts(seq, ",nobh"); 305 306 if (test_opt(sb, USRQUOTA)) 307 seq_puts(seq, ",usrquota"); 308 309 if (test_opt(sb, GRPQUOTA)) 310 seq_puts(seq, ",grpquota"); 311 312 if (test_opt(sb, XIP)) 313 seq_puts(seq, ",xip"); 314 315 if (test_opt(sb, DAX)) 316 seq_puts(seq, ",dax"); 317 318 if (!test_opt(sb, RESERVATION)) 319 seq_puts(seq, ",noreservation"); 320 321 spin_unlock(&sbi->s_lock); 322 return 0; 323 } 324 325 #ifdef CONFIG_QUOTA 326 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 327 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 328 static int ext2_quota_on(struct super_block *sb, int type, int format_id, 329 const struct path *path); 330 static struct dquot **ext2_get_dquots(struct inode *inode) 331 { 332 return EXT2_I(inode)->i_dquot; 333 } 334 335 static const struct quotactl_ops ext2_quotactl_ops = { 336 .quota_on = ext2_quota_on, 337 .quota_off = ext2_quota_off, 338 .quota_sync = dquot_quota_sync, 339 .get_state = dquot_get_state, 340 .set_info = dquot_set_dqinfo, 341 .get_dqblk = dquot_get_dqblk, 342 .set_dqblk = dquot_set_dqblk, 343 .get_nextdqblk = dquot_get_next_dqblk, 344 }; 345 #endif 346 347 static const struct super_operations ext2_sops = { 348 .alloc_inode = ext2_alloc_inode, 349 .free_inode = ext2_free_in_core_inode, 350 .write_inode = ext2_write_inode, 351 .evict_inode = ext2_evict_inode, 352 .put_super = ext2_put_super, 353 .sync_fs = ext2_sync_fs, 354 .freeze_fs = ext2_freeze, 355 .unfreeze_fs = ext2_unfreeze, 356 .statfs = ext2_statfs, 357 .remount_fs = ext2_remount, 358 .show_options = ext2_show_options, 359 #ifdef CONFIG_QUOTA 360 .quota_read = ext2_quota_read, 361 .quota_write = ext2_quota_write, 362 .get_dquots = ext2_get_dquots, 363 #endif 364 }; 365 366 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 367 u64 ino, u32 generation) 368 { 369 struct inode *inode; 370 371 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 372 return ERR_PTR(-ESTALE); 373 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 374 return ERR_PTR(-ESTALE); 375 376 /* 377 * ext2_iget isn't quite right if the inode is currently unallocated! 378 * However ext2_iget currently does appropriate checks to handle stale 379 * inodes so everything is OK. 380 */ 381 inode = ext2_iget(sb, ino); 382 if (IS_ERR(inode)) 383 return ERR_CAST(inode); 384 if (generation && inode->i_generation != generation) { 385 /* we didn't find the right inode.. */ 386 iput(inode); 387 return ERR_PTR(-ESTALE); 388 } 389 return inode; 390 } 391 392 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 393 int fh_len, int fh_type) 394 { 395 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 396 ext2_nfs_get_inode); 397 } 398 399 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 400 int fh_len, int fh_type) 401 { 402 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 403 ext2_nfs_get_inode); 404 } 405 406 static const struct export_operations ext2_export_ops = { 407 .fh_to_dentry = ext2_fh_to_dentry, 408 .fh_to_parent = ext2_fh_to_parent, 409 .get_parent = ext2_get_parent, 410 }; 411 412 static unsigned long get_sb_block(void **data) 413 { 414 unsigned long sb_block; 415 char *options = (char *) *data; 416 417 if (!options || strncmp(options, "sb=", 3) != 0) 418 return 1; /* Default location */ 419 options += 3; 420 sb_block = simple_strtoul(options, &options, 0); 421 if (*options && *options != ',') { 422 printk("EXT2-fs: Invalid sb specification: %s\n", 423 (char *) *data); 424 return 1; 425 } 426 if (*options == ',') 427 options++; 428 *data = (void *) options; 429 return sb_block; 430 } 431 432 enum { 433 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 434 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 435 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 436 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 437 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota, 438 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 439 }; 440 441 static const match_table_t tokens = { 442 {Opt_bsd_df, "bsddf"}, 443 {Opt_minix_df, "minixdf"}, 444 {Opt_grpid, "grpid"}, 445 {Opt_grpid, "bsdgroups"}, 446 {Opt_nogrpid, "nogrpid"}, 447 {Opt_nogrpid, "sysvgroups"}, 448 {Opt_resgid, "resgid=%u"}, 449 {Opt_resuid, "resuid=%u"}, 450 {Opt_sb, "sb=%u"}, 451 {Opt_err_cont, "errors=continue"}, 452 {Opt_err_panic, "errors=panic"}, 453 {Opt_err_ro, "errors=remount-ro"}, 454 {Opt_nouid32, "nouid32"}, 455 {Opt_nocheck, "check=none"}, 456 {Opt_nocheck, "nocheck"}, 457 {Opt_debug, "debug"}, 458 {Opt_oldalloc, "oldalloc"}, 459 {Opt_orlov, "orlov"}, 460 {Opt_nobh, "nobh"}, 461 {Opt_user_xattr, "user_xattr"}, 462 {Opt_nouser_xattr, "nouser_xattr"}, 463 {Opt_acl, "acl"}, 464 {Opt_noacl, "noacl"}, 465 {Opt_xip, "xip"}, 466 {Opt_dax, "dax"}, 467 {Opt_grpquota, "grpquota"}, 468 {Opt_ignore, "noquota"}, 469 {Opt_quota, "quota"}, 470 {Opt_usrquota, "usrquota"}, 471 {Opt_reservation, "reservation"}, 472 {Opt_noreservation, "noreservation"}, 473 {Opt_err, NULL} 474 }; 475 476 static int parse_options(char *options, struct super_block *sb, 477 struct ext2_mount_options *opts) 478 { 479 char *p; 480 substring_t args[MAX_OPT_ARGS]; 481 int option; 482 kuid_t uid; 483 kgid_t gid; 484 485 if (!options) 486 return 1; 487 488 while ((p = strsep (&options, ",")) != NULL) { 489 int token; 490 if (!*p) 491 continue; 492 493 token = match_token(p, tokens, args); 494 switch (token) { 495 case Opt_bsd_df: 496 clear_opt (opts->s_mount_opt, MINIX_DF); 497 break; 498 case Opt_minix_df: 499 set_opt (opts->s_mount_opt, MINIX_DF); 500 break; 501 case Opt_grpid: 502 set_opt (opts->s_mount_opt, GRPID); 503 break; 504 case Opt_nogrpid: 505 clear_opt (opts->s_mount_opt, GRPID); 506 break; 507 case Opt_resuid: 508 if (match_int(&args[0], &option)) 509 return 0; 510 uid = make_kuid(current_user_ns(), option); 511 if (!uid_valid(uid)) { 512 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option); 513 return 0; 514 515 } 516 opts->s_resuid = uid; 517 break; 518 case Opt_resgid: 519 if (match_int(&args[0], &option)) 520 return 0; 521 gid = make_kgid(current_user_ns(), option); 522 if (!gid_valid(gid)) { 523 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option); 524 return 0; 525 } 526 opts->s_resgid = gid; 527 break; 528 case Opt_sb: 529 /* handled by get_sb_block() instead of here */ 530 /* *sb_block = match_int(&args[0]); */ 531 break; 532 case Opt_err_panic: 533 clear_opt (opts->s_mount_opt, ERRORS_CONT); 534 clear_opt (opts->s_mount_opt, ERRORS_RO); 535 set_opt (opts->s_mount_opt, ERRORS_PANIC); 536 break; 537 case Opt_err_ro: 538 clear_opt (opts->s_mount_opt, ERRORS_CONT); 539 clear_opt (opts->s_mount_opt, ERRORS_PANIC); 540 set_opt (opts->s_mount_opt, ERRORS_RO); 541 break; 542 case Opt_err_cont: 543 clear_opt (opts->s_mount_opt, ERRORS_RO); 544 clear_opt (opts->s_mount_opt, ERRORS_PANIC); 545 set_opt (opts->s_mount_opt, ERRORS_CONT); 546 break; 547 case Opt_nouid32: 548 set_opt (opts->s_mount_opt, NO_UID32); 549 break; 550 case Opt_nocheck: 551 ext2_msg(sb, KERN_WARNING, 552 "Option nocheck/check=none is deprecated and" 553 " will be removed in June 2020."); 554 clear_opt (opts->s_mount_opt, CHECK); 555 break; 556 case Opt_debug: 557 set_opt (opts->s_mount_opt, DEBUG); 558 break; 559 case Opt_oldalloc: 560 set_opt (opts->s_mount_opt, OLDALLOC); 561 break; 562 case Opt_orlov: 563 clear_opt (opts->s_mount_opt, OLDALLOC); 564 break; 565 case Opt_nobh: 566 set_opt (opts->s_mount_opt, NOBH); 567 break; 568 #ifdef CONFIG_EXT2_FS_XATTR 569 case Opt_user_xattr: 570 set_opt (opts->s_mount_opt, XATTR_USER); 571 break; 572 case Opt_nouser_xattr: 573 clear_opt (opts->s_mount_opt, XATTR_USER); 574 break; 575 #else 576 case Opt_user_xattr: 577 case Opt_nouser_xattr: 578 ext2_msg(sb, KERN_INFO, "(no)user_xattr options" 579 "not supported"); 580 break; 581 #endif 582 #ifdef CONFIG_EXT2_FS_POSIX_ACL 583 case Opt_acl: 584 set_opt(opts->s_mount_opt, POSIX_ACL); 585 break; 586 case Opt_noacl: 587 clear_opt(opts->s_mount_opt, POSIX_ACL); 588 break; 589 #else 590 case Opt_acl: 591 case Opt_noacl: 592 ext2_msg(sb, KERN_INFO, 593 "(no)acl options not supported"); 594 break; 595 #endif 596 case Opt_xip: 597 ext2_msg(sb, KERN_INFO, "use dax instead of xip"); 598 set_opt(opts->s_mount_opt, XIP); 599 /* Fall through */ 600 case Opt_dax: 601 #ifdef CONFIG_FS_DAX 602 ext2_msg(sb, KERN_WARNING, 603 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk"); 604 set_opt(opts->s_mount_opt, DAX); 605 #else 606 ext2_msg(sb, KERN_INFO, "dax option not supported"); 607 #endif 608 break; 609 610 #if defined(CONFIG_QUOTA) 611 case Opt_quota: 612 case Opt_usrquota: 613 set_opt(opts->s_mount_opt, USRQUOTA); 614 break; 615 616 case Opt_grpquota: 617 set_opt(opts->s_mount_opt, GRPQUOTA); 618 break; 619 #else 620 case Opt_quota: 621 case Opt_usrquota: 622 case Opt_grpquota: 623 ext2_msg(sb, KERN_INFO, 624 "quota operations not supported"); 625 break; 626 #endif 627 628 case Opt_reservation: 629 set_opt(opts->s_mount_opt, RESERVATION); 630 ext2_msg(sb, KERN_INFO, "reservations ON"); 631 break; 632 case Opt_noreservation: 633 clear_opt(opts->s_mount_opt, RESERVATION); 634 ext2_msg(sb, KERN_INFO, "reservations OFF"); 635 break; 636 case Opt_ignore: 637 break; 638 default: 639 return 0; 640 } 641 } 642 return 1; 643 } 644 645 static int ext2_setup_super (struct super_block * sb, 646 struct ext2_super_block * es, 647 int read_only) 648 { 649 int res = 0; 650 struct ext2_sb_info *sbi = EXT2_SB(sb); 651 652 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 653 ext2_msg(sb, KERN_ERR, 654 "error: revision level too high, " 655 "forcing read-only mode"); 656 res = SB_RDONLY; 657 } 658 if (read_only) 659 return res; 660 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 661 ext2_msg(sb, KERN_WARNING, 662 "warning: mounting unchecked fs, " 663 "running e2fsck is recommended"); 664 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 665 ext2_msg(sb, KERN_WARNING, 666 "warning: mounting fs with errors, " 667 "running e2fsck is recommended"); 668 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 669 le16_to_cpu(es->s_mnt_count) >= 670 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 671 ext2_msg(sb, KERN_WARNING, 672 "warning: maximal mount count reached, " 673 "running e2fsck is recommended"); 674 else if (le32_to_cpu(es->s_checkinterval) && 675 (le32_to_cpu(es->s_lastcheck) + 676 le32_to_cpu(es->s_checkinterval) <= 677 ktime_get_real_seconds())) 678 ext2_msg(sb, KERN_WARNING, 679 "warning: checktime reached, " 680 "running e2fsck is recommended"); 681 if (!le16_to_cpu(es->s_max_mnt_count)) 682 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 683 le16_add_cpu(&es->s_mnt_count, 1); 684 if (test_opt (sb, DEBUG)) 685 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, " 686 "bpg=%lu, ipg=%lu, mo=%04lx]", 687 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 688 sbi->s_frag_size, 689 sbi->s_groups_count, 690 EXT2_BLOCKS_PER_GROUP(sb), 691 EXT2_INODES_PER_GROUP(sb), 692 sbi->s_mount_opt); 693 return res; 694 } 695 696 static int ext2_check_descriptors(struct super_block *sb) 697 { 698 int i; 699 struct ext2_sb_info *sbi = EXT2_SB(sb); 700 701 ext2_debug ("Checking group descriptors"); 702 703 for (i = 0; i < sbi->s_groups_count; i++) { 704 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 705 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 706 ext2_fsblk_t last_block; 707 708 if (i == sbi->s_groups_count - 1) 709 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 710 else 711 last_block = first_block + 712 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 713 714 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 715 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 716 { 717 ext2_error (sb, "ext2_check_descriptors", 718 "Block bitmap for group %d" 719 " not in group (block %lu)!", 720 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 721 return 0; 722 } 723 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 724 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 725 { 726 ext2_error (sb, "ext2_check_descriptors", 727 "Inode bitmap for group %d" 728 " not in group (block %lu)!", 729 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 730 return 0; 731 } 732 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 733 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 734 last_block) 735 { 736 ext2_error (sb, "ext2_check_descriptors", 737 "Inode table for group %d" 738 " not in group (block %lu)!", 739 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 740 return 0; 741 } 742 } 743 return 1; 744 } 745 746 /* 747 * Maximal file size. There is a direct, and {,double-,triple-}indirect 748 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 749 * We need to be 1 filesystem block less than the 2^32 sector limit. 750 */ 751 static loff_t ext2_max_size(int bits) 752 { 753 loff_t res = EXT2_NDIR_BLOCKS; 754 int meta_blocks; 755 unsigned int upper_limit; 756 unsigned int ppb = 1 << (bits-2); 757 758 /* This is calculated to be the largest file size for a 759 * dense, file such that the total number of 760 * sectors in the file, including data and all indirect blocks, 761 * does not exceed 2^32 -1 762 * __u32 i_blocks representing the total number of 763 * 512 bytes blocks of the file 764 */ 765 upper_limit = (1LL << 32) - 1; 766 767 /* total blocks in file system block size */ 768 upper_limit >>= (bits - 9); 769 770 /* Compute how many blocks we can address by block tree */ 771 res += 1LL << (bits-2); 772 res += 1LL << (2*(bits-2)); 773 res += 1LL << (3*(bits-2)); 774 /* Does block tree limit file size? */ 775 if (res < upper_limit) 776 goto check_lfs; 777 778 res = upper_limit; 779 /* How many metadata blocks are needed for addressing upper_limit? */ 780 upper_limit -= EXT2_NDIR_BLOCKS; 781 /* indirect blocks */ 782 meta_blocks = 1; 783 upper_limit -= ppb; 784 /* double indirect blocks */ 785 if (upper_limit < ppb * ppb) { 786 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb); 787 res -= meta_blocks; 788 goto check_lfs; 789 } 790 meta_blocks += 1 + ppb; 791 upper_limit -= ppb * ppb; 792 /* tripple indirect blocks for the rest */ 793 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) + 794 DIV_ROUND_UP(upper_limit, ppb*ppb); 795 res -= meta_blocks; 796 check_lfs: 797 res <<= bits; 798 if (res > MAX_LFS_FILESIZE) 799 res = MAX_LFS_FILESIZE; 800 801 return res; 802 } 803 804 static unsigned long descriptor_loc(struct super_block *sb, 805 unsigned long logic_sb_block, 806 int nr) 807 { 808 struct ext2_sb_info *sbi = EXT2_SB(sb); 809 unsigned long bg, first_meta_bg; 810 int has_super = 0; 811 812 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 813 814 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 815 nr < first_meta_bg) 816 return (logic_sb_block + nr + 1); 817 bg = sbi->s_desc_per_block * nr; 818 if (ext2_bg_has_super(sb, bg)) 819 has_super = 1; 820 821 return ext2_group_first_block_no(sb, bg) + has_super; 822 } 823 824 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 825 { 826 struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev); 827 struct buffer_head * bh; 828 struct ext2_sb_info * sbi; 829 struct ext2_super_block * es; 830 struct inode *root; 831 unsigned long block; 832 unsigned long sb_block = get_sb_block(&data); 833 unsigned long logic_sb_block; 834 unsigned long offset = 0; 835 unsigned long def_mount_opts; 836 long ret = -ENOMEM; 837 int blocksize = BLOCK_SIZE; 838 int db_count; 839 int i, j; 840 __le32 features; 841 int err; 842 struct ext2_mount_options opts; 843 844 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 845 if (!sbi) 846 goto failed; 847 848 sbi->s_blockgroup_lock = 849 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 850 if (!sbi->s_blockgroup_lock) { 851 kfree(sbi); 852 goto failed; 853 } 854 sb->s_fs_info = sbi; 855 sbi->s_sb_block = sb_block; 856 sbi->s_daxdev = dax_dev; 857 858 spin_lock_init(&sbi->s_lock); 859 ret = -EINVAL; 860 861 /* 862 * See what the current blocksize for the device is, and 863 * use that as the blocksize. Otherwise (or if the blocksize 864 * is smaller than the default) use the default. 865 * This is important for devices that have a hardware 866 * sectorsize that is larger than the default. 867 */ 868 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 869 if (!blocksize) { 870 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 871 goto failed_sbi; 872 } 873 874 /* 875 * If the superblock doesn't start on a hardware sector boundary, 876 * calculate the offset. 877 */ 878 if (blocksize != BLOCK_SIZE) { 879 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 880 offset = (sb_block*BLOCK_SIZE) % blocksize; 881 } else { 882 logic_sb_block = sb_block; 883 } 884 885 if (!(bh = sb_bread(sb, logic_sb_block))) { 886 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 887 goto failed_sbi; 888 } 889 /* 890 * Note: s_es must be initialized as soon as possible because 891 * some ext2 macro-instructions depend on its value 892 */ 893 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 894 sbi->s_es = es; 895 sb->s_magic = le16_to_cpu(es->s_magic); 896 897 if (sb->s_magic != EXT2_SUPER_MAGIC) 898 goto cantfind_ext2; 899 900 opts.s_mount_opt = 0; 901 /* Set defaults before we parse the mount options */ 902 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 903 if (def_mount_opts & EXT2_DEFM_DEBUG) 904 set_opt(opts.s_mount_opt, DEBUG); 905 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 906 set_opt(opts.s_mount_opt, GRPID); 907 if (def_mount_opts & EXT2_DEFM_UID16) 908 set_opt(opts.s_mount_opt, NO_UID32); 909 #ifdef CONFIG_EXT2_FS_XATTR 910 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 911 set_opt(opts.s_mount_opt, XATTR_USER); 912 #endif 913 #ifdef CONFIG_EXT2_FS_POSIX_ACL 914 if (def_mount_opts & EXT2_DEFM_ACL) 915 set_opt(opts.s_mount_opt, POSIX_ACL); 916 #endif 917 918 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 919 set_opt(opts.s_mount_opt, ERRORS_PANIC); 920 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 921 set_opt(opts.s_mount_opt, ERRORS_CONT); 922 else 923 set_opt(opts.s_mount_opt, ERRORS_RO); 924 925 opts.s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid)); 926 opts.s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid)); 927 928 set_opt(opts.s_mount_opt, RESERVATION); 929 930 if (!parse_options((char *) data, sb, &opts)) 931 goto failed_mount; 932 933 sbi->s_mount_opt = opts.s_mount_opt; 934 sbi->s_resuid = opts.s_resuid; 935 sbi->s_resgid = opts.s_resgid; 936 937 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | 938 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0); 939 sb->s_iflags |= SB_I_CGROUPWB; 940 941 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 942 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 943 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 944 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 945 ext2_msg(sb, KERN_WARNING, 946 "warning: feature flags set on rev 0 fs, " 947 "running e2fsck is recommended"); 948 /* 949 * Check feature flags regardless of the revision level, since we 950 * previously didn't change the revision level when setting the flags, 951 * so there is a chance incompat flags are set on a rev 0 filesystem. 952 */ 953 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 954 if (features) { 955 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 956 "unsupported optional features (%x)", 957 le32_to_cpu(features)); 958 goto failed_mount; 959 } 960 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 961 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 962 "unsupported optional features (%x)", 963 le32_to_cpu(features)); 964 goto failed_mount; 965 } 966 967 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 968 969 if (test_opt(sb, DAX)) { 970 if (!bdev_dax_supported(sb->s_bdev, blocksize)) { 971 ext2_msg(sb, KERN_ERR, 972 "DAX unsupported by block device. Turning off DAX."); 973 clear_opt(sbi->s_mount_opt, DAX); 974 } 975 } 976 977 /* If the blocksize doesn't match, re-read the thing.. */ 978 if (sb->s_blocksize != blocksize) { 979 brelse(bh); 980 981 if (!sb_set_blocksize(sb, blocksize)) { 982 ext2_msg(sb, KERN_ERR, 983 "error: bad blocksize %d", blocksize); 984 goto failed_sbi; 985 } 986 987 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 988 offset = (sb_block*BLOCK_SIZE) % blocksize; 989 bh = sb_bread(sb, logic_sb_block); 990 if(!bh) { 991 ext2_msg(sb, KERN_ERR, "error: couldn't read" 992 "superblock on 2nd try"); 993 goto failed_sbi; 994 } 995 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 996 sbi->s_es = es; 997 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 998 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 999 goto failed_mount; 1000 } 1001 } 1002 1003 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 1004 sb->s_max_links = EXT2_LINK_MAX; 1005 sb->s_time_min = S32_MIN; 1006 sb->s_time_max = S32_MAX; 1007 1008 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 1009 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 1010 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 1011 } else { 1012 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 1013 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 1014 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 1015 !is_power_of_2(sbi->s_inode_size) || 1016 (sbi->s_inode_size > blocksize)) { 1017 ext2_msg(sb, KERN_ERR, 1018 "error: unsupported inode size: %d", 1019 sbi->s_inode_size); 1020 goto failed_mount; 1021 } 1022 } 1023 1024 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 1025 le32_to_cpu(es->s_log_frag_size); 1026 if (sbi->s_frag_size == 0) 1027 goto cantfind_ext2; 1028 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 1029 1030 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 1031 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 1032 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 1033 1034 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 1035 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 1036 goto cantfind_ext2; 1037 sbi->s_itb_per_group = sbi->s_inodes_per_group / 1038 sbi->s_inodes_per_block; 1039 sbi->s_desc_per_block = sb->s_blocksize / 1040 sizeof (struct ext2_group_desc); 1041 sbi->s_sbh = bh; 1042 sbi->s_mount_state = le16_to_cpu(es->s_state); 1043 sbi->s_addr_per_block_bits = 1044 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 1045 sbi->s_desc_per_block_bits = 1046 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 1047 1048 if (sb->s_magic != EXT2_SUPER_MAGIC) 1049 goto cantfind_ext2; 1050 1051 if (sb->s_blocksize != bh->b_size) { 1052 if (!silent) 1053 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 1054 goto failed_mount; 1055 } 1056 1057 if (sb->s_blocksize != sbi->s_frag_size) { 1058 ext2_msg(sb, KERN_ERR, 1059 "error: fragsize %lu != blocksize %lu" 1060 "(not supported yet)", 1061 sbi->s_frag_size, sb->s_blocksize); 1062 goto failed_mount; 1063 } 1064 1065 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 1066 ext2_msg(sb, KERN_ERR, 1067 "error: #blocks per group too big: %lu", 1068 sbi->s_blocks_per_group); 1069 goto failed_mount; 1070 } 1071 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 1072 ext2_msg(sb, KERN_ERR, 1073 "error: #fragments per group too big: %lu", 1074 sbi->s_frags_per_group); 1075 goto failed_mount; 1076 } 1077 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 1078 ext2_msg(sb, KERN_ERR, 1079 "error: #inodes per group too big: %lu", 1080 sbi->s_inodes_per_group); 1081 goto failed_mount; 1082 } 1083 1084 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 1085 goto cantfind_ext2; 1086 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1087 le32_to_cpu(es->s_first_data_block) - 1) 1088 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1089 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1090 EXT2_DESC_PER_BLOCK(sb); 1091 sbi->s_group_desc = kmalloc_array (db_count, 1092 sizeof(struct buffer_head *), 1093 GFP_KERNEL); 1094 if (sbi->s_group_desc == NULL) { 1095 ret = -ENOMEM; 1096 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1097 goto failed_mount; 1098 } 1099 bgl_lock_init(sbi->s_blockgroup_lock); 1100 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1101 if (!sbi->s_debts) { 1102 ret = -ENOMEM; 1103 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1104 goto failed_mount_group_desc; 1105 } 1106 for (i = 0; i < db_count; i++) { 1107 block = descriptor_loc(sb, logic_sb_block, i); 1108 sbi->s_group_desc[i] = sb_bread(sb, block); 1109 if (!sbi->s_group_desc[i]) { 1110 for (j = 0; j < i; j++) 1111 brelse (sbi->s_group_desc[j]); 1112 ext2_msg(sb, KERN_ERR, 1113 "error: unable to read group descriptors"); 1114 goto failed_mount_group_desc; 1115 } 1116 } 1117 if (!ext2_check_descriptors (sb)) { 1118 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1119 goto failed_mount2; 1120 } 1121 sbi->s_gdb_count = db_count; 1122 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1123 spin_lock_init(&sbi->s_next_gen_lock); 1124 1125 /* per fileystem reservation list head & lock */ 1126 spin_lock_init(&sbi->s_rsv_window_lock); 1127 sbi->s_rsv_window_root = RB_ROOT; 1128 /* 1129 * Add a single, static dummy reservation to the start of the 1130 * reservation window list --- it gives us a placeholder for 1131 * append-at-start-of-list which makes the allocation logic 1132 * _much_ simpler. 1133 */ 1134 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1135 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1136 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1137 sbi->s_rsv_window_head.rsv_goal_size = 0; 1138 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1139 1140 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1141 ext2_count_free_blocks(sb), GFP_KERNEL); 1142 if (!err) { 1143 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1144 ext2_count_free_inodes(sb), GFP_KERNEL); 1145 } 1146 if (!err) { 1147 err = percpu_counter_init(&sbi->s_dirs_counter, 1148 ext2_count_dirs(sb), GFP_KERNEL); 1149 } 1150 if (err) { 1151 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1152 goto failed_mount3; 1153 } 1154 1155 #ifdef CONFIG_EXT2_FS_XATTR 1156 sbi->s_ea_block_cache = ext2_xattr_create_cache(); 1157 if (!sbi->s_ea_block_cache) { 1158 ret = -ENOMEM; 1159 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache"); 1160 goto failed_mount3; 1161 } 1162 #endif 1163 /* 1164 * set up enough so that it can read an inode 1165 */ 1166 sb->s_op = &ext2_sops; 1167 sb->s_export_op = &ext2_export_ops; 1168 sb->s_xattr = ext2_xattr_handlers; 1169 1170 #ifdef CONFIG_QUOTA 1171 sb->dq_op = &dquot_operations; 1172 sb->s_qcop = &ext2_quotactl_ops; 1173 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP; 1174 #endif 1175 1176 root = ext2_iget(sb, EXT2_ROOT_INO); 1177 if (IS_ERR(root)) { 1178 ret = PTR_ERR(root); 1179 goto failed_mount3; 1180 } 1181 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1182 iput(root); 1183 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1184 goto failed_mount3; 1185 } 1186 1187 sb->s_root = d_make_root(root); 1188 if (!sb->s_root) { 1189 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1190 ret = -ENOMEM; 1191 goto failed_mount3; 1192 } 1193 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1194 ext2_msg(sb, KERN_WARNING, 1195 "warning: mounting ext3 filesystem as ext2"); 1196 if (ext2_setup_super (sb, es, sb_rdonly(sb))) 1197 sb->s_flags |= SB_RDONLY; 1198 ext2_write_super(sb); 1199 return 0; 1200 1201 cantfind_ext2: 1202 if (!silent) 1203 ext2_msg(sb, KERN_ERR, 1204 "error: can't find an ext2 filesystem on dev %s.", 1205 sb->s_id); 1206 goto failed_mount; 1207 failed_mount3: 1208 ext2_xattr_destroy_cache(sbi->s_ea_block_cache); 1209 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1210 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1211 percpu_counter_destroy(&sbi->s_dirs_counter); 1212 failed_mount2: 1213 for (i = 0; i < db_count; i++) 1214 brelse(sbi->s_group_desc[i]); 1215 failed_mount_group_desc: 1216 kfree(sbi->s_group_desc); 1217 kfree(sbi->s_debts); 1218 failed_mount: 1219 brelse(bh); 1220 failed_sbi: 1221 sb->s_fs_info = NULL; 1222 kfree(sbi->s_blockgroup_lock); 1223 kfree(sbi); 1224 failed: 1225 fs_put_dax(dax_dev); 1226 return ret; 1227 } 1228 1229 static void ext2_clear_super_error(struct super_block *sb) 1230 { 1231 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1232 1233 if (buffer_write_io_error(sbh)) { 1234 /* 1235 * Oh, dear. A previous attempt to write the 1236 * superblock failed. This could happen because the 1237 * USB device was yanked out. Or it could happen to 1238 * be a transient write error and maybe the block will 1239 * be remapped. Nothing we can do but to retry the 1240 * write and hope for the best. 1241 */ 1242 ext2_msg(sb, KERN_ERR, 1243 "previous I/O error to superblock detected"); 1244 clear_buffer_write_io_error(sbh); 1245 set_buffer_uptodate(sbh); 1246 } 1247 } 1248 1249 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, 1250 int wait) 1251 { 1252 ext2_clear_super_error(sb); 1253 spin_lock(&EXT2_SB(sb)->s_lock); 1254 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1255 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1256 es->s_wtime = cpu_to_le32(ktime_get_real_seconds()); 1257 /* unlock before we do IO */ 1258 spin_unlock(&EXT2_SB(sb)->s_lock); 1259 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1260 if (wait) 1261 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1262 } 1263 1264 /* 1265 * In the second extended file system, it is not necessary to 1266 * write the super block since we use a mapping of the 1267 * disk super block in a buffer. 1268 * 1269 * However, this function is still used to set the fs valid 1270 * flags to 0. We need to set this flag to 0 since the fs 1271 * may have been checked while mounted and e2fsck may have 1272 * set s_state to EXT2_VALID_FS after some corrections. 1273 */ 1274 static int ext2_sync_fs(struct super_block *sb, int wait) 1275 { 1276 struct ext2_sb_info *sbi = EXT2_SB(sb); 1277 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1278 1279 /* 1280 * Write quota structures to quota file, sync_blockdev() will write 1281 * them to disk later 1282 */ 1283 dquot_writeback_dquots(sb, -1); 1284 1285 spin_lock(&sbi->s_lock); 1286 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1287 ext2_debug("setting valid to 0\n"); 1288 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1289 } 1290 spin_unlock(&sbi->s_lock); 1291 ext2_sync_super(sb, es, wait); 1292 return 0; 1293 } 1294 1295 static int ext2_freeze(struct super_block *sb) 1296 { 1297 struct ext2_sb_info *sbi = EXT2_SB(sb); 1298 1299 /* 1300 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared 1301 * because we have unattached inodes and thus filesystem is not fully 1302 * consistent. 1303 */ 1304 if (atomic_long_read(&sb->s_remove_count)) { 1305 ext2_sync_fs(sb, 1); 1306 return 0; 1307 } 1308 /* Set EXT2_FS_VALID flag */ 1309 spin_lock(&sbi->s_lock); 1310 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); 1311 spin_unlock(&sbi->s_lock); 1312 ext2_sync_super(sb, sbi->s_es, 1); 1313 1314 return 0; 1315 } 1316 1317 static int ext2_unfreeze(struct super_block *sb) 1318 { 1319 /* Just write sb to clear EXT2_VALID_FS flag */ 1320 ext2_write_super(sb); 1321 1322 return 0; 1323 } 1324 1325 static void ext2_write_super(struct super_block *sb) 1326 { 1327 if (!sb_rdonly(sb)) 1328 ext2_sync_fs(sb, 1); 1329 } 1330 1331 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1332 { 1333 struct ext2_sb_info * sbi = EXT2_SB(sb); 1334 struct ext2_super_block * es; 1335 struct ext2_mount_options new_opts; 1336 int err; 1337 1338 sync_filesystem(sb); 1339 1340 spin_lock(&sbi->s_lock); 1341 new_opts.s_mount_opt = sbi->s_mount_opt; 1342 new_opts.s_resuid = sbi->s_resuid; 1343 new_opts.s_resgid = sbi->s_resgid; 1344 spin_unlock(&sbi->s_lock); 1345 1346 if (!parse_options(data, sb, &new_opts)) 1347 return -EINVAL; 1348 1349 spin_lock(&sbi->s_lock); 1350 es = sbi->s_es; 1351 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) { 1352 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1353 "dax flag with busy inodes while remounting"); 1354 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX; 1355 } 1356 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) 1357 goto out_set; 1358 if (*flags & SB_RDONLY) { 1359 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1360 !(sbi->s_mount_state & EXT2_VALID_FS)) 1361 goto out_set; 1362 1363 /* 1364 * OK, we are remounting a valid rw partition rdonly, so set 1365 * the rdonly flag and then mark the partition as valid again. 1366 */ 1367 es->s_state = cpu_to_le16(sbi->s_mount_state); 1368 es->s_mtime = cpu_to_le32(ktime_get_real_seconds()); 1369 spin_unlock(&sbi->s_lock); 1370 1371 err = dquot_suspend(sb, -1); 1372 if (err < 0) 1373 return err; 1374 1375 ext2_sync_super(sb, es, 1); 1376 } else { 1377 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1378 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1379 if (ret) { 1380 spin_unlock(&sbi->s_lock); 1381 ext2_msg(sb, KERN_WARNING, 1382 "warning: couldn't remount RDWR because of " 1383 "unsupported optional features (%x).", 1384 le32_to_cpu(ret)); 1385 return -EROFS; 1386 } 1387 /* 1388 * Mounting a RDONLY partition read-write, so reread and 1389 * store the current valid flag. (It may have been changed 1390 * by e2fsck since we originally mounted the partition.) 1391 */ 1392 sbi->s_mount_state = le16_to_cpu(es->s_state); 1393 if (!ext2_setup_super (sb, es, 0)) 1394 sb->s_flags &= ~SB_RDONLY; 1395 spin_unlock(&sbi->s_lock); 1396 1397 ext2_write_super(sb); 1398 1399 dquot_resume(sb, -1); 1400 } 1401 1402 spin_lock(&sbi->s_lock); 1403 out_set: 1404 sbi->s_mount_opt = new_opts.s_mount_opt; 1405 sbi->s_resuid = new_opts.s_resuid; 1406 sbi->s_resgid = new_opts.s_resgid; 1407 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | 1408 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0); 1409 spin_unlock(&sbi->s_lock); 1410 1411 return 0; 1412 } 1413 1414 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1415 { 1416 struct super_block *sb = dentry->d_sb; 1417 struct ext2_sb_info *sbi = EXT2_SB(sb); 1418 struct ext2_super_block *es = sbi->s_es; 1419 u64 fsid; 1420 1421 spin_lock(&sbi->s_lock); 1422 1423 if (test_opt (sb, MINIX_DF)) 1424 sbi->s_overhead_last = 0; 1425 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1426 unsigned long i, overhead = 0; 1427 smp_rmb(); 1428 1429 /* 1430 * Compute the overhead (FS structures). This is constant 1431 * for a given filesystem unless the number of block groups 1432 * changes so we cache the previous value until it does. 1433 */ 1434 1435 /* 1436 * All of the blocks before first_data_block are 1437 * overhead 1438 */ 1439 overhead = le32_to_cpu(es->s_first_data_block); 1440 1441 /* 1442 * Add the overhead attributed to the superblock and 1443 * block group descriptors. If the sparse superblocks 1444 * feature is turned on, then not all groups have this. 1445 */ 1446 for (i = 0; i < sbi->s_groups_count; i++) 1447 overhead += ext2_bg_has_super(sb, i) + 1448 ext2_bg_num_gdb(sb, i); 1449 1450 /* 1451 * Every block group has an inode bitmap, a block 1452 * bitmap, and an inode table. 1453 */ 1454 overhead += (sbi->s_groups_count * 1455 (2 + sbi->s_itb_per_group)); 1456 sbi->s_overhead_last = overhead; 1457 smp_wmb(); 1458 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1459 } 1460 1461 buf->f_type = EXT2_SUPER_MAGIC; 1462 buf->f_bsize = sb->s_blocksize; 1463 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1464 buf->f_bfree = ext2_count_free_blocks(sb); 1465 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1466 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1467 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1468 buf->f_bavail = 0; 1469 buf->f_files = le32_to_cpu(es->s_inodes_count); 1470 buf->f_ffree = ext2_count_free_inodes(sb); 1471 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1472 buf->f_namelen = EXT2_NAME_LEN; 1473 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1474 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1475 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1476 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1477 spin_unlock(&sbi->s_lock); 1478 return 0; 1479 } 1480 1481 static struct dentry *ext2_mount(struct file_system_type *fs_type, 1482 int flags, const char *dev_name, void *data) 1483 { 1484 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1485 } 1486 1487 #ifdef CONFIG_QUOTA 1488 1489 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1490 * acquiring the locks... As quota files are never truncated and quota code 1491 * itself serializes the operations (and no one else should touch the files) 1492 * we don't have to be afraid of races */ 1493 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1494 size_t len, loff_t off) 1495 { 1496 struct inode *inode = sb_dqopt(sb)->files[type]; 1497 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1498 int err = 0; 1499 int offset = off & (sb->s_blocksize - 1); 1500 int tocopy; 1501 size_t toread; 1502 struct buffer_head tmp_bh; 1503 struct buffer_head *bh; 1504 loff_t i_size = i_size_read(inode); 1505 1506 if (off > i_size) 1507 return 0; 1508 if (off+len > i_size) 1509 len = i_size-off; 1510 toread = len; 1511 while (toread > 0) { 1512 tocopy = sb->s_blocksize - offset < toread ? 1513 sb->s_blocksize - offset : toread; 1514 1515 tmp_bh.b_state = 0; 1516 tmp_bh.b_size = sb->s_blocksize; 1517 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1518 if (err < 0) 1519 return err; 1520 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1521 memset(data, 0, tocopy); 1522 else { 1523 bh = sb_bread(sb, tmp_bh.b_blocknr); 1524 if (!bh) 1525 return -EIO; 1526 memcpy(data, bh->b_data+offset, tocopy); 1527 brelse(bh); 1528 } 1529 offset = 0; 1530 toread -= tocopy; 1531 data += tocopy; 1532 blk++; 1533 } 1534 return len; 1535 } 1536 1537 /* Write to quotafile */ 1538 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1539 const char *data, size_t len, loff_t off) 1540 { 1541 struct inode *inode = sb_dqopt(sb)->files[type]; 1542 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1543 int err = 0; 1544 int offset = off & (sb->s_blocksize - 1); 1545 int tocopy; 1546 size_t towrite = len; 1547 struct buffer_head tmp_bh; 1548 struct buffer_head *bh; 1549 1550 while (towrite > 0) { 1551 tocopy = sb->s_blocksize - offset < towrite ? 1552 sb->s_blocksize - offset : towrite; 1553 1554 tmp_bh.b_state = 0; 1555 tmp_bh.b_size = sb->s_blocksize; 1556 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1557 if (err < 0) 1558 goto out; 1559 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1560 bh = sb_bread(sb, tmp_bh.b_blocknr); 1561 else 1562 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1563 if (unlikely(!bh)) { 1564 err = -EIO; 1565 goto out; 1566 } 1567 lock_buffer(bh); 1568 memcpy(bh->b_data+offset, data, tocopy); 1569 flush_dcache_page(bh->b_page); 1570 set_buffer_uptodate(bh); 1571 mark_buffer_dirty(bh); 1572 unlock_buffer(bh); 1573 brelse(bh); 1574 offset = 0; 1575 towrite -= tocopy; 1576 data += tocopy; 1577 blk++; 1578 } 1579 out: 1580 if (len == towrite) 1581 return err; 1582 if (inode->i_size < off+len-towrite) 1583 i_size_write(inode, off+len-towrite); 1584 inode_inc_iversion(inode); 1585 inode->i_mtime = inode->i_ctime = current_time(inode); 1586 mark_inode_dirty(inode); 1587 return len - towrite; 1588 } 1589 1590 static int ext2_quota_on(struct super_block *sb, int type, int format_id, 1591 const struct path *path) 1592 { 1593 int err; 1594 struct inode *inode; 1595 1596 err = dquot_quota_on(sb, type, format_id, path); 1597 if (err) 1598 return err; 1599 1600 inode = d_inode(path->dentry); 1601 inode_lock(inode); 1602 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL; 1603 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE, 1604 S_NOATIME | S_IMMUTABLE); 1605 inode_unlock(inode); 1606 mark_inode_dirty(inode); 1607 1608 return 0; 1609 } 1610 1611 static int ext2_quota_off(struct super_block *sb, int type) 1612 { 1613 struct inode *inode = sb_dqopt(sb)->files[type]; 1614 int err; 1615 1616 if (!inode || !igrab(inode)) 1617 goto out; 1618 1619 err = dquot_quota_off(sb, type); 1620 if (err) 1621 goto out_put; 1622 1623 inode_lock(inode); 1624 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL); 1625 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE); 1626 inode_unlock(inode); 1627 mark_inode_dirty(inode); 1628 out_put: 1629 iput(inode); 1630 return err; 1631 out: 1632 return dquot_quota_off(sb, type); 1633 } 1634 1635 #endif 1636 1637 static struct file_system_type ext2_fs_type = { 1638 .owner = THIS_MODULE, 1639 .name = "ext2", 1640 .mount = ext2_mount, 1641 .kill_sb = kill_block_super, 1642 .fs_flags = FS_REQUIRES_DEV, 1643 }; 1644 MODULE_ALIAS_FS("ext2"); 1645 1646 static int __init init_ext2_fs(void) 1647 { 1648 int err; 1649 1650 err = init_inodecache(); 1651 if (err) 1652 return err; 1653 err = register_filesystem(&ext2_fs_type); 1654 if (err) 1655 goto out; 1656 return 0; 1657 out: 1658 destroy_inodecache(); 1659 return err; 1660 } 1661 1662 static void __exit exit_ext2_fs(void) 1663 { 1664 unregister_filesystem(&ext2_fs_type); 1665 destroy_inodecache(); 1666 } 1667 1668 MODULE_AUTHOR("Remy Card and others"); 1669 MODULE_DESCRIPTION("Second Extended Filesystem"); 1670 MODULE_LICENSE("GPL"); 1671 module_init(init_ext2_fs) 1672 module_exit(exit_ext2_fs) 1673