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/fs_context.h> 27 #include <linux/fs_parser.h> 28 #include <linux/random.h> 29 #include <linux/buffer_head.h> 30 #include <linux/exportfs.h> 31 #include <linux/vfs.h> 32 #include <linux/seq_file.h> 33 #include <linux/mount.h> 34 #include <linux/log2.h> 35 #include <linux/quotaops.h> 36 #include <linux/uaccess.h> 37 #include <linux/dax.h> 38 #include <linux/iversion.h> 39 #include "ext2.h" 40 #include "xattr.h" 41 #include "acl.h" 42 43 static void ext2_write_super(struct super_block *sb); 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 static void ext2_msg_fc(struct fs_context *fc, const char *prefix, 85 const char *fmt, ...) 86 { 87 struct va_format vaf; 88 va_list args; 89 const char *s_id; 90 91 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) { 92 s_id = fc->root->d_sb->s_id; 93 } else { 94 /* get last path component of source */ 95 s_id = strrchr(fc->source, '/'); 96 if (s_id) 97 s_id++; 98 else 99 s_id = fc->source; 100 } 101 va_start(args, fmt); 102 103 vaf.fmt = fmt; 104 vaf.va = &args; 105 106 printk("%sEXT2-fs (%s): %pV\n", prefix, s_id, &vaf); 107 108 va_end(args); 109 } 110 111 void ext2_msg(struct super_block *sb, const char *prefix, 112 const char *fmt, ...) 113 { 114 struct va_format vaf; 115 va_list args; 116 117 va_start(args, fmt); 118 119 vaf.fmt = fmt; 120 vaf.va = &args; 121 122 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf); 123 124 va_end(args); 125 } 126 127 /* 128 * This must be called with sbi->s_lock held. 129 */ 130 void ext2_update_dynamic_rev(struct super_block *sb) 131 { 132 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 133 134 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) 135 return; 136 137 ext2_msg(sb, KERN_WARNING, 138 "warning: updating to rev %d because of " 139 "new feature flag, running e2fsck is recommended", 140 EXT2_DYNAMIC_REV); 141 142 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); 143 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); 144 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); 145 /* leave es->s_feature_*compat flags alone */ 146 /* es->s_uuid will be set by e2fsck if empty */ 147 148 /* 149 * The rest of the superblock fields should be zero, and if not it 150 * means they are likely already in use, so leave them alone. We 151 * can leave it up to e2fsck to clean up any inconsistencies there. 152 */ 153 } 154 155 #ifdef CONFIG_QUOTA 156 static int ext2_quota_off(struct super_block *sb, int type); 157 158 static void ext2_quota_off_umount(struct super_block *sb) 159 { 160 int type; 161 162 for (type = 0; type < MAXQUOTAS; type++) 163 ext2_quota_off(sb, type); 164 } 165 #else 166 static inline void ext2_quota_off_umount(struct super_block *sb) 167 { 168 } 169 #endif 170 171 static void ext2_put_super (struct super_block * sb) 172 { 173 int db_count; 174 int i; 175 struct ext2_sb_info *sbi = EXT2_SB(sb); 176 177 ext2_quota_off_umount(sb); 178 179 ext2_xattr_destroy_cache(sbi->s_ea_block_cache); 180 sbi->s_ea_block_cache = NULL; 181 182 if (!sb_rdonly(sb)) { 183 struct ext2_super_block *es = sbi->s_es; 184 185 spin_lock(&sbi->s_lock); 186 es->s_state = cpu_to_le16(sbi->s_mount_state); 187 spin_unlock(&sbi->s_lock); 188 ext2_sync_super(sb, es, 1); 189 } 190 db_count = sbi->s_gdb_count; 191 for (i = 0; i < db_count; i++) 192 brelse(sbi->s_group_desc[i]); 193 kvfree(sbi->s_group_desc); 194 kfree(sbi->s_debts); 195 percpu_counter_destroy(&sbi->s_freeblocks_counter); 196 percpu_counter_destroy(&sbi->s_freeinodes_counter); 197 percpu_counter_destroy(&sbi->s_dirs_counter); 198 brelse (sbi->s_sbh); 199 sb->s_fs_info = NULL; 200 kfree(sbi->s_blockgroup_lock); 201 fs_put_dax(sbi->s_daxdev, NULL); 202 kfree(sbi); 203 } 204 205 static struct kmem_cache * ext2_inode_cachep; 206 207 static struct inode *ext2_alloc_inode(struct super_block *sb) 208 { 209 struct ext2_inode_info *ei; 210 ei = alloc_inode_sb(sb, ext2_inode_cachep, GFP_KERNEL); 211 if (!ei) 212 return NULL; 213 ei->i_block_alloc_info = NULL; 214 inode_set_iversion(&ei->vfs_inode, 1); 215 #ifdef CONFIG_QUOTA 216 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot)); 217 #endif 218 mmb_init(&ei->i_metadata_bhs, &ei->vfs_inode.i_data); 219 220 return &ei->vfs_inode; 221 } 222 223 static void ext2_free_in_core_inode(struct inode *inode) 224 { 225 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 226 } 227 228 static void init_once(void *foo) 229 { 230 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 231 232 rwlock_init(&ei->i_meta_lock); 233 #ifdef CONFIG_EXT2_FS_XATTR 234 init_rwsem(&ei->xattr_sem); 235 #endif 236 mutex_init(&ei->truncate_mutex); 237 inode_init_once(&ei->vfs_inode); 238 } 239 240 static int __init init_inodecache(void) 241 { 242 ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache", 243 sizeof(struct ext2_inode_info), 0, 244 SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT, 245 offsetof(struct ext2_inode_info, i_data), 246 sizeof_field(struct ext2_inode_info, i_data), 247 init_once); 248 if (ext2_inode_cachep == NULL) 249 return -ENOMEM; 250 return 0; 251 } 252 253 static void destroy_inodecache(void) 254 { 255 /* 256 * Make sure all delayed rcu free inodes are flushed before we 257 * destroy cache. 258 */ 259 rcu_barrier(); 260 kmem_cache_destroy(ext2_inode_cachep); 261 } 262 263 static int ext2_show_options(struct seq_file *seq, struct dentry *root) 264 { 265 struct super_block *sb = root->d_sb; 266 struct ext2_sb_info *sbi = EXT2_SB(sb); 267 struct ext2_super_block *es = sbi->s_es; 268 unsigned long def_mount_opts; 269 270 spin_lock(&sbi->s_lock); 271 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 272 273 if (sbi->s_sb_block != 1) 274 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 275 if (test_opt(sb, MINIX_DF)) 276 seq_puts(seq, ",minixdf"); 277 if (test_opt(sb, GRPID)) 278 seq_puts(seq, ",grpid"); 279 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 280 seq_puts(seq, ",nogrpid"); 281 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) || 282 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 283 seq_printf(seq, ",resuid=%u", 284 from_kuid_munged(&init_user_ns, sbi->s_resuid)); 285 } 286 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) || 287 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 288 seq_printf(seq, ",resgid=%u", 289 from_kgid_munged(&init_user_ns, sbi->s_resgid)); 290 } 291 if (test_opt(sb, ERRORS_RO)) { 292 int def_errors = le16_to_cpu(es->s_errors); 293 294 if (def_errors == EXT2_ERRORS_PANIC || 295 def_errors == EXT2_ERRORS_CONTINUE) { 296 seq_puts(seq, ",errors=remount-ro"); 297 } 298 } 299 if (test_opt(sb, ERRORS_CONT)) 300 seq_puts(seq, ",errors=continue"); 301 if (test_opt(sb, ERRORS_PANIC)) 302 seq_puts(seq, ",errors=panic"); 303 if (test_opt(sb, NO_UID32)) 304 seq_puts(seq, ",nouid32"); 305 if (test_opt(sb, DEBUG)) 306 seq_puts(seq, ",debug"); 307 if (test_opt(sb, OLDALLOC)) 308 seq_puts(seq, ",oldalloc"); 309 310 #ifdef CONFIG_EXT2_FS_XATTR 311 if (test_opt(sb, XATTR_USER)) 312 seq_puts(seq, ",user_xattr"); 313 if (!test_opt(sb, XATTR_USER) && 314 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 315 seq_puts(seq, ",nouser_xattr"); 316 } 317 #endif 318 319 #ifdef CONFIG_EXT2_FS_POSIX_ACL 320 if (test_opt(sb, POSIX_ACL)) 321 seq_puts(seq, ",acl"); 322 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 323 seq_puts(seq, ",noacl"); 324 #endif 325 326 if (test_opt(sb, USRQUOTA)) 327 seq_puts(seq, ",usrquota"); 328 329 if (test_opt(sb, GRPQUOTA)) 330 seq_puts(seq, ",grpquota"); 331 332 if (test_opt(sb, XIP)) 333 seq_puts(seq, ",xip"); 334 335 if (test_opt(sb, DAX)) 336 seq_puts(seq, ",dax"); 337 338 if (!test_opt(sb, RESERVATION)) 339 seq_puts(seq, ",noreservation"); 340 341 spin_unlock(&sbi->s_lock); 342 return 0; 343 } 344 345 #ifdef CONFIG_QUOTA 346 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 347 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 348 static int ext2_quota_on(struct super_block *sb, int type, int format_id, 349 const struct path *path); 350 static struct dquot __rcu **ext2_get_dquots(struct inode *inode) 351 { 352 return EXT2_I(inode)->i_dquot; 353 } 354 355 static const struct quotactl_ops ext2_quotactl_ops = { 356 .quota_on = ext2_quota_on, 357 .quota_off = ext2_quota_off, 358 .quota_sync = dquot_quota_sync, 359 .get_state = dquot_get_state, 360 .set_info = dquot_set_dqinfo, 361 .get_dqblk = dquot_get_dqblk, 362 .set_dqblk = dquot_set_dqblk, 363 .get_nextdqblk = dquot_get_next_dqblk, 364 }; 365 #endif 366 367 static const struct super_operations ext2_sops = { 368 .alloc_inode = ext2_alloc_inode, 369 .free_inode = ext2_free_in_core_inode, 370 .write_inode = ext2_write_inode, 371 .evict_inode = ext2_evict_inode, 372 .put_super = ext2_put_super, 373 .sync_fs = ext2_sync_fs, 374 .freeze_fs = ext2_freeze, 375 .unfreeze_fs = ext2_unfreeze, 376 .statfs = ext2_statfs, 377 .show_options = ext2_show_options, 378 #ifdef CONFIG_QUOTA 379 .quota_read = ext2_quota_read, 380 .quota_write = ext2_quota_write, 381 .get_dquots = ext2_get_dquots, 382 #endif 383 }; 384 385 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 386 u64 ino, u32 generation) 387 { 388 struct inode *inode; 389 390 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 391 return ERR_PTR(-ESTALE); 392 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 393 return ERR_PTR(-ESTALE); 394 395 /* 396 * ext2_iget isn't quite right if the inode is currently unallocated! 397 * However ext2_iget currently does appropriate checks to handle stale 398 * inodes so everything is OK. 399 */ 400 inode = ext2_iget(sb, ino); 401 if (IS_ERR(inode)) 402 return ERR_CAST(inode); 403 if (generation && inode->i_generation != generation) { 404 /* we didn't find the right inode.. */ 405 iput(inode); 406 return ERR_PTR(-ESTALE); 407 } 408 return inode; 409 } 410 411 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 412 int fh_len, int fh_type) 413 { 414 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 415 ext2_nfs_get_inode); 416 } 417 418 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 419 int fh_len, int fh_type) 420 { 421 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 422 ext2_nfs_get_inode); 423 } 424 425 static const struct export_operations ext2_export_ops = { 426 .encode_fh = generic_encode_ino32_fh, 427 .fh_to_dentry = ext2_fh_to_dentry, 428 .fh_to_parent = ext2_fh_to_parent, 429 .get_parent = ext2_get_parent, 430 }; 431 432 enum { 433 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, Opt_resgid, Opt_resuid, 434 Opt_sb, Opt_errors, Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov, 435 Opt_nobh, Opt_user_xattr, Opt_acl, Opt_xip, Opt_dax, Opt_ignore, 436 Opt_quota, Opt_usrquota, Opt_grpquota, Opt_reservation, 437 }; 438 439 static const struct constant_table ext2_param_errors[] = { 440 {"continue", EXT2_MOUNT_ERRORS_CONT}, 441 {"panic", EXT2_MOUNT_ERRORS_PANIC}, 442 {"remount-ro", EXT2_MOUNT_ERRORS_RO}, 443 {} 444 }; 445 446 static const struct fs_parameter_spec ext2_param_spec[] = { 447 fsparam_flag ("bsddf", Opt_bsd_df), 448 fsparam_flag ("minixdf", Opt_minix_df), 449 fsparam_flag ("grpid", Opt_grpid), 450 fsparam_flag ("bsdgroups", Opt_grpid), 451 fsparam_flag ("nogrpid", Opt_nogrpid), 452 fsparam_flag ("sysvgroups", Opt_nogrpid), 453 fsparam_gid ("resgid", Opt_resgid), 454 fsparam_uid ("resuid", Opt_resuid), 455 fsparam_u32 ("sb", Opt_sb), 456 fsparam_enum ("errors", Opt_errors, ext2_param_errors), 457 fsparam_flag ("nouid32", Opt_nouid32), 458 fsparam_flag ("debug", Opt_debug), 459 fsparam_flag ("oldalloc", Opt_oldalloc), 460 fsparam_flag ("orlov", Opt_orlov), 461 fsparam_flag ("nobh", Opt_nobh), 462 fsparam_flag_no ("user_xattr", Opt_user_xattr), 463 fsparam_flag_no ("acl", Opt_acl), 464 fsparam_flag ("xip", Opt_xip), 465 fsparam_flag ("dax", Opt_dax), 466 fsparam_flag ("grpquota", Opt_grpquota), 467 fsparam_flag ("noquota", Opt_ignore), 468 fsparam_flag ("quota", Opt_quota), 469 fsparam_flag ("usrquota", Opt_usrquota), 470 fsparam_flag_no ("reservation", Opt_reservation), 471 {} 472 }; 473 474 #define EXT2_SPEC_s_resuid (1 << 0) 475 #define EXT2_SPEC_s_resgid (1 << 1) 476 477 struct ext2_fs_context { 478 unsigned long vals_s_flags; /* Bits to set in s_flags */ 479 unsigned long mask_s_flags; /* Bits changed in s_flags */ 480 unsigned int vals_s_mount_opt; 481 unsigned int mask_s_mount_opt; 482 kuid_t s_resuid; 483 kgid_t s_resgid; 484 unsigned long s_sb_block; 485 unsigned int spec; 486 487 }; 488 489 static inline void ctx_set_mount_opt(struct ext2_fs_context *ctx, 490 unsigned long flag) 491 { 492 ctx->mask_s_mount_opt |= flag; 493 ctx->vals_s_mount_opt |= flag; 494 } 495 496 static inline void ctx_clear_mount_opt(struct ext2_fs_context *ctx, 497 unsigned long flag) 498 { 499 ctx->mask_s_mount_opt |= flag; 500 ctx->vals_s_mount_opt &= ~flag; 501 } 502 503 static inline unsigned long 504 ctx_test_mount_opt(struct ext2_fs_context *ctx, unsigned long flag) 505 { 506 return (ctx->vals_s_mount_opt & flag); 507 } 508 509 static inline bool 510 ctx_parsed_mount_opt(struct ext2_fs_context *ctx, unsigned long flag) 511 { 512 return (ctx->mask_s_mount_opt & flag); 513 } 514 515 static void ext2_free_fc(struct fs_context *fc) 516 { 517 kfree(fc->fs_private); 518 } 519 520 static int ext2_parse_param(struct fs_context *fc, struct fs_parameter *param) 521 { 522 struct ext2_fs_context *ctx = fc->fs_private; 523 int opt; 524 struct fs_parse_result result; 525 526 opt = fs_parse(fc, ext2_param_spec, param, &result); 527 if (opt < 0) 528 return opt; 529 530 switch (opt) { 531 case Opt_bsd_df: 532 ctx_clear_mount_opt(ctx, EXT2_MOUNT_MINIX_DF); 533 break; 534 case Opt_minix_df: 535 ctx_set_mount_opt(ctx, EXT2_MOUNT_MINIX_DF); 536 break; 537 case Opt_grpid: 538 ctx_set_mount_opt(ctx, EXT2_MOUNT_GRPID); 539 break; 540 case Opt_nogrpid: 541 ctx_clear_mount_opt(ctx, EXT2_MOUNT_GRPID); 542 break; 543 case Opt_resuid: 544 ctx->s_resuid = result.uid; 545 ctx->spec |= EXT2_SPEC_s_resuid; 546 break; 547 case Opt_resgid: 548 ctx->s_resgid = result.gid; 549 ctx->spec |= EXT2_SPEC_s_resgid; 550 break; 551 case Opt_sb: 552 /* Note that this is silently ignored on remount */ 553 ctx->s_sb_block = result.uint_32; 554 break; 555 case Opt_errors: 556 ctx_clear_mount_opt(ctx, EXT2_MOUNT_ERRORS_MASK); 557 ctx_set_mount_opt(ctx, result.uint_32); 558 break; 559 case Opt_nouid32: 560 ctx_set_mount_opt(ctx, EXT2_MOUNT_NO_UID32); 561 break; 562 case Opt_debug: 563 ctx_set_mount_opt(ctx, EXT2_MOUNT_DEBUG); 564 break; 565 case Opt_oldalloc: 566 ctx_set_mount_opt(ctx, EXT2_MOUNT_OLDALLOC); 567 break; 568 case Opt_orlov: 569 ctx_clear_mount_opt(ctx, EXT2_MOUNT_OLDALLOC); 570 break; 571 case Opt_nobh: 572 ext2_msg_fc(fc, KERN_INFO, "nobh option not supported\n"); 573 break; 574 #ifdef CONFIG_EXT2_FS_XATTR 575 case Opt_user_xattr: 576 if (!result.negated) 577 ctx_set_mount_opt(ctx, EXT2_MOUNT_XATTR_USER); 578 else 579 ctx_clear_mount_opt(ctx, EXT2_MOUNT_XATTR_USER); 580 break; 581 #else 582 case Opt_user_xattr: 583 ext2_msg_fc(fc, KERN_INFO, "(no)user_xattr options not supported"); 584 break; 585 #endif 586 #ifdef CONFIG_EXT2_FS_POSIX_ACL 587 case Opt_acl: 588 if (!result.negated) 589 ctx_set_mount_opt(ctx, EXT2_MOUNT_POSIX_ACL); 590 else 591 ctx_clear_mount_opt(ctx, EXT2_MOUNT_POSIX_ACL); 592 break; 593 #else 594 case Opt_acl: 595 ext2_msg_fc(fc, KERN_INFO, "(no)acl options not supported"); 596 break; 597 #endif 598 case Opt_xip: 599 ext2_msg_fc(fc, KERN_INFO, "use dax instead of xip"); 600 ctx_set_mount_opt(ctx, EXT2_MOUNT_XIP); 601 fallthrough; 602 case Opt_dax: 603 #ifdef CONFIG_FS_DAX 604 ext2_msg_fc(fc, KERN_WARNING, 605 "DAX enabled. Warning: DAX support in ext2 driver is deprecated" 606 " and will be removed at the end of 2025. Please use ext4 driver instead."); 607 ctx_set_mount_opt(ctx, EXT2_MOUNT_DAX); 608 #else 609 ext2_msg_fc(fc, KERN_INFO, "dax option not supported"); 610 #endif 611 break; 612 613 #if defined(CONFIG_QUOTA) 614 case Opt_quota: 615 case Opt_usrquota: 616 ctx_set_mount_opt(ctx, EXT2_MOUNT_USRQUOTA); 617 break; 618 619 case Opt_grpquota: 620 ctx_set_mount_opt(ctx, EXT2_MOUNT_GRPQUOTA); 621 break; 622 #else 623 case Opt_quota: 624 case Opt_usrquota: 625 case Opt_grpquota: 626 ext2_msg_fc(fc, KERN_INFO, "quota operations not supported"); 627 break; 628 #endif 629 case Opt_reservation: 630 if (!result.negated) { 631 ctx_set_mount_opt(ctx, EXT2_MOUNT_RESERVATION); 632 ext2_msg_fc(fc, KERN_INFO, "reservations ON"); 633 } else { 634 ctx_clear_mount_opt(ctx, EXT2_MOUNT_RESERVATION); 635 ext2_msg_fc(fc, KERN_INFO, "reservations OFF"); 636 } 637 break; 638 case Opt_ignore: 639 break; 640 default: 641 return -EINVAL; 642 } 643 return 0; 644 } 645 646 static int ext2_setup_super (struct super_block * sb, 647 struct ext2_super_block * es, 648 int read_only) 649 { 650 int res = 0; 651 struct ext2_sb_info *sbi = EXT2_SB(sb); 652 653 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 654 ext2_msg(sb, KERN_ERR, 655 "error: revision level too high, " 656 "forcing read-only mode"); 657 res = SB_RDONLY; 658 } 659 if (read_only) 660 return res; 661 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 662 ext2_msg(sb, KERN_WARNING, 663 "warning: mounting unchecked fs, " 664 "running e2fsck is recommended"); 665 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 666 ext2_msg(sb, KERN_WARNING, 667 "warning: mounting fs with errors, " 668 "running e2fsck is recommended"); 669 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 670 le16_to_cpu(es->s_mnt_count) >= 671 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 672 ext2_msg(sb, KERN_WARNING, 673 "warning: maximal mount count reached, " 674 "running e2fsck is recommended"); 675 else if (le32_to_cpu(es->s_checkinterval) && 676 (le32_to_cpu(es->s_lastcheck) + 677 le32_to_cpu(es->s_checkinterval) <= 678 ktime_get_real_seconds())) 679 ext2_msg(sb, KERN_WARNING, 680 "warning: checktime reached, " 681 "running e2fsck is recommended"); 682 if (!le16_to_cpu(es->s_max_mnt_count)) 683 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 684 le16_add_cpu(&es->s_mnt_count, 1); 685 if (test_opt (sb, DEBUG)) 686 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, gc=%lu, " 687 "bpg=%lu, ipg=%lu, mo=%04lx]", 688 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 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 = ext2_group_last_block_no(sb, i); 707 708 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 709 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 710 { 711 ext2_error (sb, "ext2_check_descriptors", 712 "Block bitmap for group %d" 713 " not in group (block %lu)!", 714 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 715 return 0; 716 } 717 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 718 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 719 { 720 ext2_error (sb, "ext2_check_descriptors", 721 "Inode bitmap for group %d" 722 " not in group (block %lu)!", 723 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 724 return 0; 725 } 726 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 727 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 728 last_block) 729 { 730 ext2_error (sb, "ext2_check_descriptors", 731 "Inode table for group %d" 732 " not in group (block %lu)!", 733 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 734 return 0; 735 } 736 } 737 return 1; 738 } 739 740 /* 741 * Maximal file size. There is a direct, and {,double-,triple-}indirect 742 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 743 * We need to be 1 filesystem block less than the 2^32 sector limit. 744 */ 745 static loff_t ext2_max_size(int bits) 746 { 747 loff_t res = EXT2_NDIR_BLOCKS; 748 int meta_blocks; 749 unsigned int upper_limit; 750 unsigned int ppb = 1 << (bits-2); 751 752 /* This is calculated to be the largest file size for a 753 * dense, file such that the total number of 754 * sectors in the file, including data and all indirect blocks, 755 * does not exceed 2^32 -1 756 * __u32 i_blocks representing the total number of 757 * 512 bytes blocks of the file 758 */ 759 upper_limit = (1LL << 32) - 1; 760 761 /* total blocks in file system block size */ 762 upper_limit >>= (bits - 9); 763 764 /* Compute how many blocks we can address by block tree */ 765 res += 1LL << (bits-2); 766 res += 1LL << (2*(bits-2)); 767 res += 1LL << (3*(bits-2)); 768 /* Compute how many metadata blocks are needed */ 769 meta_blocks = 1; 770 meta_blocks += 1 + ppb; 771 meta_blocks += 1 + ppb + ppb * ppb; 772 /* Does block tree limit file size? */ 773 if (res + meta_blocks <= upper_limit) 774 goto check_lfs; 775 776 res = upper_limit; 777 /* How many metadata blocks are needed for addressing upper_limit? */ 778 upper_limit -= EXT2_NDIR_BLOCKS; 779 /* indirect blocks */ 780 meta_blocks = 1; 781 upper_limit -= ppb; 782 /* double indirect blocks */ 783 if (upper_limit < ppb * ppb) { 784 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb); 785 res -= meta_blocks; 786 goto check_lfs; 787 } 788 meta_blocks += 1 + ppb; 789 upper_limit -= ppb * ppb; 790 /* tripple indirect blocks for the rest */ 791 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) + 792 DIV_ROUND_UP(upper_limit, ppb*ppb); 793 res -= meta_blocks; 794 check_lfs: 795 res <<= bits; 796 if (res > MAX_LFS_FILESIZE) 797 res = MAX_LFS_FILESIZE; 798 799 return res; 800 } 801 802 static unsigned long descriptor_loc(struct super_block *sb, 803 unsigned long logic_sb_block, 804 int nr) 805 { 806 struct ext2_sb_info *sbi = EXT2_SB(sb); 807 unsigned long bg, first_meta_bg; 808 809 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 810 811 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 812 nr < first_meta_bg) 813 return (logic_sb_block + nr + 1); 814 bg = sbi->s_desc_per_block * nr; 815 816 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg); 817 } 818 819 /* 820 * Set all mount options either from defaults on disk, or from parsed 821 * options. Parsed/specified options override on-disk defaults. 822 */ 823 static void ext2_set_options(struct fs_context *fc, struct ext2_sb_info *sbi) 824 { 825 struct ext2_fs_context *ctx = fc->fs_private; 826 struct ext2_super_block *es = sbi->s_es; 827 unsigned long def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 828 829 /* Copy parsed mount options to sbi */ 830 sbi->s_mount_opt = ctx->vals_s_mount_opt; 831 832 /* Use in-superblock defaults only if not specified during parsing */ 833 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_DEBUG) && 834 def_mount_opts & EXT2_DEFM_DEBUG) 835 set_opt(sbi->s_mount_opt, DEBUG); 836 837 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_GRPID) && 838 def_mount_opts & EXT2_DEFM_BSDGROUPS) 839 set_opt(sbi->s_mount_opt, GRPID); 840 841 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_NO_UID32) && 842 def_mount_opts & EXT2_DEFM_UID16) 843 set_opt(sbi->s_mount_opt, NO_UID32); 844 845 #ifdef CONFIG_EXT2_FS_XATTR 846 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_XATTR_USER) && 847 def_mount_opts & EXT2_DEFM_XATTR_USER) 848 set_opt(sbi->s_mount_opt, XATTR_USER); 849 #endif 850 #ifdef CONFIG_EXT2_FS_POSIX_ACL 851 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_POSIX_ACL) && 852 def_mount_opts & EXT2_DEFM_ACL) 853 set_opt(sbi->s_mount_opt, POSIX_ACL); 854 #endif 855 856 if (!ctx_parsed_mount_opt(ctx, EXT2_MOUNT_ERRORS_MASK)) { 857 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 858 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 859 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 860 set_opt(sbi->s_mount_opt, ERRORS_CONT); 861 else 862 set_opt(sbi->s_mount_opt, ERRORS_RO); 863 } 864 865 if (ctx->spec & EXT2_SPEC_s_resuid) 866 sbi->s_resuid = ctx->s_resuid; 867 else 868 sbi->s_resuid = make_kuid(&init_user_ns, 869 le16_to_cpu(es->s_def_resuid)); 870 871 if (ctx->spec & EXT2_SPEC_s_resgid) 872 sbi->s_resgid = ctx->s_resgid; 873 else 874 sbi->s_resgid = make_kgid(&init_user_ns, 875 le16_to_cpu(es->s_def_resgid)); 876 } 877 878 static int ext2_fill_super(struct super_block *sb, struct fs_context *fc) 879 { 880 struct ext2_fs_context *ctx = fc->fs_private; 881 int silent = fc->sb_flags & SB_SILENT; 882 struct buffer_head * bh; 883 struct ext2_sb_info * sbi; 884 struct ext2_super_block * es; 885 struct inode *root; 886 unsigned long block; 887 unsigned long sb_block = ctx->s_sb_block; 888 unsigned long logic_sb_block; 889 unsigned long offset = 0; 890 long ret = -ENOMEM; 891 int blocksize = BLOCK_SIZE; 892 int db_count; 893 int i, j; 894 __le32 features; 895 int err; 896 897 sbi = kzalloc_obj(*sbi); 898 if (!sbi) 899 return -ENOMEM; 900 901 sbi->s_blockgroup_lock = 902 kzalloc_obj(struct blockgroup_lock); 903 if (!sbi->s_blockgroup_lock) { 904 kfree(sbi); 905 return -ENOMEM; 906 } 907 sb->s_fs_info = sbi; 908 sbi->s_sb_block = sb_block; 909 sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off, 910 NULL, NULL); 911 912 spin_lock_init(&sbi->s_lock); 913 ret = -EINVAL; 914 915 /* 916 * See what the current blocksize for the device is, and 917 * use that as the blocksize. Otherwise (or if the blocksize 918 * is smaller than the default) use the default. 919 * This is important for devices that have a hardware 920 * sectorsize that is larger than the default. 921 */ 922 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 923 if (!blocksize) { 924 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 925 goto failed_sbi; 926 } 927 928 /* 929 * If the superblock doesn't start on a hardware sector boundary, 930 * calculate the offset. 931 */ 932 if (blocksize != BLOCK_SIZE) { 933 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 934 offset = (sb_block*BLOCK_SIZE) % blocksize; 935 } else { 936 logic_sb_block = sb_block; 937 } 938 939 if (!(bh = sb_bread(sb, logic_sb_block))) { 940 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 941 goto failed_sbi; 942 } 943 /* 944 * Note: s_es must be initialized as soon as possible because 945 * some ext2 macro-instructions depend on its value 946 */ 947 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 948 sbi->s_es = es; 949 sb->s_magic = le16_to_cpu(es->s_magic); 950 951 if (sb->s_magic != EXT2_SUPER_MAGIC) 952 goto cantfind_ext2; 953 954 ext2_set_options(fc, sbi); 955 956 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | 957 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0); 958 sb->s_iflags |= SB_I_CGROUPWB; 959 960 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 961 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 962 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 963 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 964 ext2_msg(sb, KERN_WARNING, 965 "warning: feature flags set on rev 0 fs, " 966 "running e2fsck is recommended"); 967 /* 968 * Check feature flags regardless of the revision level, since we 969 * previously didn't change the revision level when setting the flags, 970 * so there is a chance incompat flags are set on a rev 0 filesystem. 971 */ 972 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 973 if (features) { 974 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 975 "unsupported optional features (%x)", 976 le32_to_cpu(features)); 977 goto failed_mount; 978 } 979 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 980 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 981 "unsupported optional features (%x)", 982 le32_to_cpu(features)); 983 goto failed_mount; 984 } 985 986 if (le32_to_cpu(es->s_log_block_size) > 987 (EXT2_MAX_BLOCK_LOG_SIZE - BLOCK_SIZE_BITS)) { 988 ext2_msg(sb, KERN_ERR, 989 "Invalid log block size: %u", 990 le32_to_cpu(es->s_log_block_size)); 991 goto failed_mount; 992 } 993 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 994 995 if (test_opt(sb, DAX)) { 996 if (!sbi->s_daxdev) { 997 ext2_msg(sb, KERN_ERR, 998 "DAX unsupported by block device. Turning off DAX."); 999 clear_opt(sbi->s_mount_opt, DAX); 1000 } else if (blocksize != PAGE_SIZE) { 1001 ext2_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n"); 1002 clear_opt(sbi->s_mount_opt, DAX); 1003 } 1004 } 1005 1006 /* If the blocksize doesn't match, re-read the thing.. */ 1007 if (sb->s_blocksize != blocksize) { 1008 brelse(bh); 1009 1010 if (!sb_set_blocksize(sb, blocksize)) { 1011 ext2_msg(sb, KERN_ERR, 1012 "error: bad blocksize %d", blocksize); 1013 goto failed_sbi; 1014 } 1015 1016 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 1017 offset = (sb_block*BLOCK_SIZE) % blocksize; 1018 bh = sb_bread(sb, logic_sb_block); 1019 if(!bh) { 1020 ext2_msg(sb, KERN_ERR, "error: couldn't read" 1021 "superblock on 2nd try"); 1022 goto failed_sbi; 1023 } 1024 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 1025 sbi->s_es = es; 1026 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 1027 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 1028 goto failed_mount; 1029 } 1030 } 1031 1032 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 1033 sb->s_max_links = EXT2_LINK_MAX; 1034 sb->s_time_min = S32_MIN; 1035 sb->s_time_max = S32_MAX; 1036 1037 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 1038 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 1039 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 1040 } else { 1041 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 1042 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 1043 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 1044 !is_power_of_2(sbi->s_inode_size) || 1045 (sbi->s_inode_size > blocksize)) { 1046 ext2_msg(sb, KERN_ERR, 1047 "error: unsupported inode size: %d", 1048 sbi->s_inode_size); 1049 goto failed_mount; 1050 } 1051 } 1052 1053 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 1054 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 1055 1056 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 1057 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 1058 goto cantfind_ext2; 1059 sbi->s_itb_per_group = sbi->s_inodes_per_group / 1060 sbi->s_inodes_per_block; 1061 sbi->s_desc_per_block = sb->s_blocksize / 1062 sizeof (struct ext2_group_desc); 1063 sbi->s_sbh = bh; 1064 sbi->s_mount_state = le16_to_cpu(es->s_state); 1065 sbi->s_addr_per_block_bits = 1066 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 1067 sbi->s_desc_per_block_bits = 1068 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 1069 1070 if (sb->s_magic != EXT2_SUPER_MAGIC) 1071 goto cantfind_ext2; 1072 1073 if (sb->s_blocksize != bh->b_size) { 1074 if (!silent) 1075 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 1076 goto failed_mount; 1077 } 1078 1079 if (es->s_log_frag_size != es->s_log_block_size) { 1080 ext2_msg(sb, KERN_ERR, 1081 "error: fragsize log %u != blocksize log %u", 1082 le32_to_cpu(es->s_log_frag_size), sb->s_blocksize_bits); 1083 goto failed_mount; 1084 } 1085 1086 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 1087 ext2_msg(sb, KERN_ERR, 1088 "error: #blocks per group too big: %lu", 1089 sbi->s_blocks_per_group); 1090 goto failed_mount; 1091 } 1092 /* At least inode table, bitmaps, and sb have to fit in one group */ 1093 if (sbi->s_blocks_per_group <= sbi->s_itb_per_group + 3) { 1094 ext2_msg(sb, KERN_ERR, 1095 "error: #blocks per group smaller than metadata size: %lu <= %lu", 1096 sbi->s_blocks_per_group, sbi->s_inodes_per_group + 3); 1097 goto failed_mount; 1098 } 1099 if (sbi->s_inodes_per_group < sbi->s_inodes_per_block || 1100 sbi->s_inodes_per_group > sb->s_blocksize * 8) { 1101 ext2_msg(sb, KERN_ERR, 1102 "error: invalid #inodes per group: %lu", 1103 sbi->s_inodes_per_group); 1104 goto failed_mount; 1105 } 1106 if (sb_bdev_nr_blocks(sb) < le32_to_cpu(es->s_blocks_count)) { 1107 ext2_msg(sb, KERN_ERR, 1108 "bad geometry: block count %u exceeds size of device (%u blocks)", 1109 le32_to_cpu(es->s_blocks_count), 1110 (unsigned)sb_bdev_nr_blocks(sb)); 1111 goto failed_mount; 1112 } 1113 1114 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1115 le32_to_cpu(es->s_first_data_block) - 1) 1116 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1117 if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group != 1118 le32_to_cpu(es->s_inodes_count)) { 1119 ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu", 1120 le32_to_cpu(es->s_inodes_count), 1121 (u64)sbi->s_groups_count * sbi->s_inodes_per_group); 1122 goto failed_mount; 1123 } 1124 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1125 EXT2_DESC_PER_BLOCK(sb); 1126 sbi->s_group_desc = kvmalloc_objs(struct buffer_head *, db_count); 1127 if (sbi->s_group_desc == NULL) { 1128 ret = -ENOMEM; 1129 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1130 goto failed_mount; 1131 } 1132 bgl_lock_init(sbi->s_blockgroup_lock); 1133 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1134 if (!sbi->s_debts) { 1135 ret = -ENOMEM; 1136 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1137 goto failed_mount_group_desc; 1138 } 1139 for (i = 0; i < db_count; i++) { 1140 block = descriptor_loc(sb, logic_sb_block, i); 1141 sbi->s_group_desc[i] = sb_bread(sb, block); 1142 if (!sbi->s_group_desc[i]) { 1143 for (j = 0; j < i; j++) 1144 brelse (sbi->s_group_desc[j]); 1145 ext2_msg(sb, KERN_ERR, 1146 "error: unable to read group descriptors"); 1147 goto failed_mount_group_desc; 1148 } 1149 } 1150 if (!ext2_check_descriptors (sb)) { 1151 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1152 goto failed_mount2; 1153 } 1154 sbi->s_gdb_count = db_count; 1155 sbi->s_next_generation = get_random_u32(); 1156 spin_lock_init(&sbi->s_next_gen_lock); 1157 1158 /* per filesystem reservation list head & lock */ 1159 spin_lock_init(&sbi->s_rsv_window_lock); 1160 sbi->s_rsv_window_root = RB_ROOT; 1161 /* 1162 * Add a single, static dummy reservation to the start of the 1163 * reservation window list --- it gives us a placeholder for 1164 * append-at-start-of-list which makes the allocation logic 1165 * _much_ simpler. 1166 */ 1167 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1168 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1169 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1170 sbi->s_rsv_window_head.rsv_goal_size = 0; 1171 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1172 1173 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1174 ext2_count_free_blocks(sb), GFP_KERNEL); 1175 if (!err) { 1176 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1177 ext2_count_free_inodes(sb), GFP_KERNEL); 1178 } 1179 if (!err) { 1180 err = percpu_counter_init(&sbi->s_dirs_counter, 1181 ext2_count_dirs(sb), GFP_KERNEL); 1182 } 1183 if (err) { 1184 ret = err; 1185 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1186 goto failed_mount3; 1187 } 1188 1189 #ifdef CONFIG_EXT2_FS_XATTR 1190 sbi->s_ea_block_cache = ext2_xattr_create_cache(); 1191 if (!sbi->s_ea_block_cache) { 1192 ret = -ENOMEM; 1193 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache"); 1194 goto failed_mount3; 1195 } 1196 #endif 1197 /* 1198 * set up enough so that it can read an inode 1199 */ 1200 sb->s_op = &ext2_sops; 1201 sb->s_export_op = &ext2_export_ops; 1202 sb->s_xattr = ext2_xattr_handlers; 1203 1204 #ifdef CONFIG_QUOTA 1205 sb->dq_op = &dquot_operations; 1206 sb->s_qcop = &ext2_quotactl_ops; 1207 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP; 1208 #endif 1209 1210 root = ext2_iget(sb, EXT2_ROOT_INO); 1211 if (IS_ERR(root)) { 1212 ret = PTR_ERR(root); 1213 goto failed_mount3; 1214 } 1215 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1216 iput(root); 1217 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1218 goto failed_mount3; 1219 } 1220 1221 sb->s_root = d_make_root(root); 1222 if (!sb->s_root) { 1223 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1224 ret = -ENOMEM; 1225 goto failed_mount3; 1226 } 1227 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1228 ext2_msg(sb, KERN_WARNING, 1229 "warning: mounting ext3 filesystem as ext2"); 1230 if (ext2_setup_super (sb, es, sb_rdonly(sb))) 1231 sb->s_flags |= SB_RDONLY; 1232 ext2_write_super(sb); 1233 return 0; 1234 1235 cantfind_ext2: 1236 if (!silent) 1237 ext2_msg(sb, KERN_ERR, 1238 "error: can't find an ext2 filesystem on dev %s.", 1239 sb->s_id); 1240 goto failed_mount; 1241 failed_mount3: 1242 ext2_xattr_destroy_cache(sbi->s_ea_block_cache); 1243 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1244 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1245 percpu_counter_destroy(&sbi->s_dirs_counter); 1246 failed_mount2: 1247 for (i = 0; i < db_count; i++) 1248 brelse(sbi->s_group_desc[i]); 1249 failed_mount_group_desc: 1250 kvfree(sbi->s_group_desc); 1251 kfree(sbi->s_debts); 1252 failed_mount: 1253 brelse(bh); 1254 failed_sbi: 1255 fs_put_dax(sbi->s_daxdev, NULL); 1256 sb->s_fs_info = NULL; 1257 kfree(sbi->s_blockgroup_lock); 1258 kfree(sbi); 1259 return ret; 1260 } 1261 1262 static void ext2_clear_super_error(struct super_block *sb) 1263 { 1264 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1265 1266 if (buffer_write_io_error(sbh)) { 1267 /* 1268 * Oh, dear. A previous attempt to write the 1269 * superblock failed. This could happen because the 1270 * USB device was yanked out. Or it could happen to 1271 * be a transient write error and maybe the block will 1272 * be remapped. Nothing we can do but to retry the 1273 * write and hope for the best. 1274 */ 1275 ext2_msg(sb, KERN_ERR, 1276 "previous I/O error to superblock detected"); 1277 clear_buffer_write_io_error(sbh); 1278 set_buffer_uptodate(sbh); 1279 } 1280 } 1281 1282 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, 1283 int wait) 1284 { 1285 ext2_clear_super_error(sb); 1286 spin_lock(&EXT2_SB(sb)->s_lock); 1287 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1288 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1289 es->s_wtime = cpu_to_le32(ktime_get_real_seconds()); 1290 /* unlock before we do IO */ 1291 spin_unlock(&EXT2_SB(sb)->s_lock); 1292 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1293 if (wait) 1294 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1295 } 1296 1297 /* 1298 * In the second extended file system, it is not necessary to 1299 * write the super block since we use a mapping of the 1300 * disk super block in a buffer. 1301 * 1302 * However, this function is still used to set the fs valid 1303 * flags to 0. We need to set this flag to 0 since the fs 1304 * may have been checked while mounted and e2fsck may have 1305 * set s_state to EXT2_VALID_FS after some corrections. 1306 */ 1307 static int ext2_sync_fs(struct super_block *sb, int wait) 1308 { 1309 struct ext2_sb_info *sbi = EXT2_SB(sb); 1310 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1311 1312 /* 1313 * Write quota structures to quota file, sync_blockdev() will write 1314 * them to disk later 1315 */ 1316 dquot_writeback_dquots(sb, -1); 1317 1318 spin_lock(&sbi->s_lock); 1319 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1320 ext2_debug("setting valid to 0\n"); 1321 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1322 } 1323 spin_unlock(&sbi->s_lock); 1324 ext2_sync_super(sb, es, wait); 1325 return 0; 1326 } 1327 1328 static int ext2_freeze(struct super_block *sb) 1329 { 1330 struct ext2_sb_info *sbi = EXT2_SB(sb); 1331 1332 /* 1333 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared 1334 * because we have unattached inodes and thus filesystem is not fully 1335 * consistent. 1336 */ 1337 if (atomic_long_read(&sb->s_remove_count)) { 1338 ext2_sync_fs(sb, 1); 1339 return 0; 1340 } 1341 /* Set EXT2_FS_VALID flag */ 1342 spin_lock(&sbi->s_lock); 1343 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); 1344 spin_unlock(&sbi->s_lock); 1345 ext2_sync_super(sb, sbi->s_es, 1); 1346 1347 return 0; 1348 } 1349 1350 static int ext2_unfreeze(struct super_block *sb) 1351 { 1352 /* Just write sb to clear EXT2_VALID_FS flag */ 1353 ext2_write_super(sb); 1354 1355 return 0; 1356 } 1357 1358 static void ext2_write_super(struct super_block *sb) 1359 { 1360 if (!sb_rdonly(sb)) 1361 ext2_sync_fs(sb, 1); 1362 } 1363 1364 static int ext2_reconfigure(struct fs_context *fc) 1365 { 1366 struct ext2_fs_context *ctx = fc->fs_private; 1367 struct super_block *sb = fc->root->d_sb; 1368 struct ext2_sb_info * sbi = EXT2_SB(sb); 1369 struct ext2_super_block * es; 1370 struct ext2_mount_options new_opts; 1371 int flags = fc->sb_flags; 1372 int err; 1373 1374 sync_filesystem(sb); 1375 1376 new_opts.s_mount_opt = ctx->vals_s_mount_opt; 1377 new_opts.s_resuid = ctx->s_resuid; 1378 new_opts.s_resgid = ctx->s_resgid; 1379 1380 spin_lock(&sbi->s_lock); 1381 es = sbi->s_es; 1382 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) { 1383 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1384 "dax flag with busy inodes while remounting"); 1385 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX; 1386 } 1387 if ((bool)(flags & SB_RDONLY) == sb_rdonly(sb)) 1388 goto out_set; 1389 if (flags & SB_RDONLY) { 1390 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1391 !(sbi->s_mount_state & EXT2_VALID_FS)) 1392 goto out_set; 1393 1394 /* 1395 * OK, we are remounting a valid rw partition rdonly, so set 1396 * the rdonly flag and then mark the partition as valid again. 1397 */ 1398 es->s_state = cpu_to_le16(sbi->s_mount_state); 1399 es->s_mtime = cpu_to_le32(ktime_get_real_seconds()); 1400 spin_unlock(&sbi->s_lock); 1401 1402 err = dquot_suspend(sb, -1); 1403 if (err < 0) 1404 return err; 1405 1406 ext2_sync_super(sb, es, 1); 1407 } else { 1408 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1409 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1410 if (ret) { 1411 spin_unlock(&sbi->s_lock); 1412 ext2_msg(sb, KERN_WARNING, 1413 "warning: couldn't remount RDWR because of " 1414 "unsupported optional features (%x).", 1415 le32_to_cpu(ret)); 1416 return -EROFS; 1417 } 1418 /* 1419 * Mounting a RDONLY partition read-write, so reread and 1420 * store the current valid flag. (It may have been changed 1421 * by e2fsck since we originally mounted the partition.) 1422 */ 1423 sbi->s_mount_state = le16_to_cpu(es->s_state); 1424 if (!ext2_setup_super (sb, es, 0)) 1425 sb->s_flags &= ~SB_RDONLY; 1426 spin_unlock(&sbi->s_lock); 1427 1428 ext2_write_super(sb); 1429 1430 dquot_resume(sb, -1); 1431 } 1432 1433 spin_lock(&sbi->s_lock); 1434 out_set: 1435 sbi->s_mount_opt = new_opts.s_mount_opt; 1436 sbi->s_resuid = new_opts.s_resuid; 1437 sbi->s_resgid = new_opts.s_resgid; 1438 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | 1439 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0); 1440 spin_unlock(&sbi->s_lock); 1441 1442 return 0; 1443 } 1444 1445 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1446 { 1447 struct super_block *sb = dentry->d_sb; 1448 struct ext2_sb_info *sbi = EXT2_SB(sb); 1449 struct ext2_super_block *es = sbi->s_es; 1450 1451 spin_lock(&sbi->s_lock); 1452 1453 if (test_opt (sb, MINIX_DF)) 1454 sbi->s_overhead_last = 0; 1455 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1456 unsigned long i, overhead = 0; 1457 smp_rmb(); 1458 1459 /* 1460 * Compute the overhead (FS structures). This is constant 1461 * for a given filesystem unless the number of block groups 1462 * changes so we cache the previous value until it does. 1463 */ 1464 1465 /* 1466 * All of the blocks before first_data_block are 1467 * overhead 1468 */ 1469 overhead = le32_to_cpu(es->s_first_data_block); 1470 1471 /* 1472 * Add the overhead attributed to the superblock and 1473 * block group descriptors. If the sparse superblocks 1474 * feature is turned on, then not all groups have this. 1475 */ 1476 for (i = 0; i < sbi->s_groups_count; i++) 1477 overhead += ext2_bg_has_super(sb, i) + 1478 ext2_bg_num_gdb(sb, i); 1479 1480 /* 1481 * Every block group has an inode bitmap, a block 1482 * bitmap, and an inode table. 1483 */ 1484 overhead += (sbi->s_groups_count * 1485 (2 + sbi->s_itb_per_group)); 1486 sbi->s_overhead_last = overhead; 1487 smp_wmb(); 1488 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1489 } 1490 1491 buf->f_type = EXT2_SUPER_MAGIC; 1492 buf->f_bsize = sb->s_blocksize; 1493 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1494 buf->f_bfree = ext2_count_free_blocks(sb); 1495 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1496 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1497 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1498 buf->f_bavail = 0; 1499 buf->f_files = le32_to_cpu(es->s_inodes_count); 1500 buf->f_ffree = ext2_count_free_inodes(sb); 1501 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1502 buf->f_namelen = EXT2_NAME_LEN; 1503 buf->f_fsid = uuid_to_fsid(es->s_uuid); 1504 spin_unlock(&sbi->s_lock); 1505 return 0; 1506 } 1507 1508 static int ext2_get_tree(struct fs_context *fc) 1509 { 1510 return get_tree_bdev(fc, ext2_fill_super); 1511 } 1512 1513 #ifdef CONFIG_QUOTA 1514 1515 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1516 * acquiring the locks... As quota files are never truncated and quota code 1517 * itself serializes the operations (and no one else should touch the files) 1518 * we don't have to be afraid of races */ 1519 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1520 size_t len, loff_t off) 1521 { 1522 struct inode *inode = sb_dqopt(sb)->files[type]; 1523 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1524 int err = 0; 1525 int offset = off & (sb->s_blocksize - 1); 1526 int tocopy; 1527 size_t toread; 1528 struct buffer_head tmp_bh; 1529 struct buffer_head *bh; 1530 loff_t i_size = i_size_read(inode); 1531 1532 if (off > i_size) 1533 return 0; 1534 if (off+len > i_size) 1535 len = i_size-off; 1536 toread = len; 1537 while (toread > 0) { 1538 tocopy = min_t(size_t, sb->s_blocksize - offset, toread); 1539 1540 tmp_bh.b_state = 0; 1541 tmp_bh.b_size = sb->s_blocksize; 1542 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1543 if (err < 0) 1544 return err; 1545 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1546 memset(data, 0, tocopy); 1547 else { 1548 bh = sb_bread(sb, tmp_bh.b_blocknr); 1549 if (!bh) 1550 return -EIO; 1551 memcpy(data, bh->b_data+offset, tocopy); 1552 brelse(bh); 1553 } 1554 offset = 0; 1555 toread -= tocopy; 1556 data += tocopy; 1557 blk++; 1558 } 1559 return len; 1560 } 1561 1562 /* Write to quotafile */ 1563 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1564 const char *data, size_t len, loff_t off) 1565 { 1566 struct inode *inode = sb_dqopt(sb)->files[type]; 1567 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1568 int err = 0; 1569 int offset = off & (sb->s_blocksize - 1); 1570 int tocopy; 1571 size_t towrite = len; 1572 struct buffer_head tmp_bh; 1573 struct buffer_head *bh; 1574 1575 while (towrite > 0) { 1576 tocopy = min_t(size_t, sb->s_blocksize - offset, towrite); 1577 1578 tmp_bh.b_state = 0; 1579 tmp_bh.b_size = sb->s_blocksize; 1580 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1581 if (err < 0) 1582 goto out; 1583 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1584 bh = sb_bread(sb, tmp_bh.b_blocknr); 1585 else 1586 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1587 if (unlikely(!bh)) { 1588 err = -EIO; 1589 goto out; 1590 } 1591 lock_buffer(bh); 1592 memcpy(bh->b_data+offset, data, tocopy); 1593 flush_dcache_folio(bh->b_folio); 1594 set_buffer_uptodate(bh); 1595 mark_buffer_dirty(bh); 1596 unlock_buffer(bh); 1597 brelse(bh); 1598 offset = 0; 1599 towrite -= tocopy; 1600 data += tocopy; 1601 blk++; 1602 } 1603 out: 1604 if (len == towrite) 1605 return err; 1606 if (inode->i_size < off+len-towrite) 1607 i_size_write(inode, off+len-towrite); 1608 inode_inc_iversion(inode); 1609 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); 1610 mark_inode_dirty(inode); 1611 return len - towrite; 1612 } 1613 1614 static int ext2_quota_on(struct super_block *sb, int type, int format_id, 1615 const struct path *path) 1616 { 1617 int err; 1618 struct inode *inode; 1619 1620 err = dquot_quota_on(sb, type, format_id, path); 1621 if (err) 1622 return err; 1623 1624 inode = d_inode(path->dentry); 1625 inode_lock(inode); 1626 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL; 1627 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE, 1628 S_NOATIME | S_IMMUTABLE); 1629 inode_unlock(inode); 1630 mark_inode_dirty(inode); 1631 1632 return 0; 1633 } 1634 1635 static int ext2_quota_off(struct super_block *sb, int type) 1636 { 1637 struct inode *inode = sb_dqopt(sb)->files[type]; 1638 int err; 1639 1640 if (!inode || !igrab(inode)) 1641 goto out; 1642 1643 err = dquot_quota_off(sb, type); 1644 if (err) 1645 goto out_put; 1646 1647 inode_lock(inode); 1648 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL); 1649 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE); 1650 inode_unlock(inode); 1651 mark_inode_dirty(inode); 1652 out_put: 1653 iput(inode); 1654 return err; 1655 out: 1656 return dquot_quota_off(sb, type); 1657 } 1658 1659 #endif 1660 1661 static const struct fs_context_operations ext2_context_ops = { 1662 .parse_param = ext2_parse_param, 1663 .get_tree = ext2_get_tree, 1664 .reconfigure = ext2_reconfigure, 1665 .free = ext2_free_fc, 1666 }; 1667 1668 static int ext2_init_fs_context(struct fs_context *fc) 1669 { 1670 struct ext2_fs_context *ctx; 1671 1672 ctx = kzalloc_obj(*ctx); 1673 if (!ctx) 1674 return -ENOMEM; 1675 1676 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) { 1677 struct super_block *sb = fc->root->d_sb; 1678 struct ext2_sb_info *sbi = EXT2_SB(sb); 1679 1680 spin_lock(&sbi->s_lock); 1681 ctx->vals_s_mount_opt = sbi->s_mount_opt; 1682 ctx->vals_s_flags = sb->s_flags; 1683 ctx->s_resuid = sbi->s_resuid; 1684 ctx->s_resgid = sbi->s_resgid; 1685 spin_unlock(&sbi->s_lock); 1686 } else { 1687 ctx->s_sb_block = 1; 1688 ctx_set_mount_opt(ctx, EXT2_MOUNT_RESERVATION); 1689 } 1690 1691 fc->fs_private = ctx; 1692 fc->ops = &ext2_context_ops; 1693 1694 return 0; 1695 } 1696 1697 static struct file_system_type ext2_fs_type = { 1698 .owner = THIS_MODULE, 1699 .name = "ext2", 1700 .kill_sb = kill_block_super, 1701 .fs_flags = FS_REQUIRES_DEV, 1702 .init_fs_context = ext2_init_fs_context, 1703 .parameters = ext2_param_spec, 1704 }; 1705 MODULE_ALIAS_FS("ext2"); 1706 1707 static int __init init_ext2_fs(void) 1708 { 1709 int err; 1710 1711 err = init_inodecache(); 1712 if (err) 1713 return err; 1714 err = register_filesystem(&ext2_fs_type); 1715 if (err) 1716 goto out; 1717 return 0; 1718 out: 1719 destroy_inodecache(); 1720 return err; 1721 } 1722 1723 static void __exit exit_ext2_fs(void) 1724 { 1725 unregister_filesystem(&ext2_fs_type); 1726 destroy_inodecache(); 1727 } 1728 1729 MODULE_AUTHOR("Remy Card and others"); 1730 MODULE_DESCRIPTION("Second Extended Filesystem"); 1731 MODULE_LICENSE("GPL"); 1732 module_init(init_ext2_fs) 1733 module_exit(exit_ext2_fs) 1734