1/* 2 * linux/fs/ext2/super.c 3 * 4 * Copyright (C) 1992, 1993, 1994, 1995 5 * Remy Card (card@masi.ibp.fr) 6 * Laboratoire MASI - Institut Blaise Pascal 7 * Universite Pierre et Marie Curie (Paris VI) 8 * 9 * from 10 * 11 * linux/fs/minix/inode.c 12 * 13 * Copyright (C) 1991, 1992 Linus Torvalds 14 * 15 * Big-endian to little-endian byte-swapping/bitmaps by 16 * David S. Miller (davem@caip.rutgers.edu), 1995 17 */ 18 19#include <linux/module.h> 20#include <linux/string.h> 21#include <linux/fs.h> 22#include <linux/slab.h> 23#include <linux/init.h> 24#include <linux/blkdev.h> 25#include <linux/parser.h> 26#include <linux/random.h> 27#include <linux/buffer_head.h> 28#include <linux/exportfs.h> 29#include <linux/vfs.h> 30#include <linux/seq_file.h> 31#include <linux/mount.h> 32#include <linux/log2.h> 33#include <linux/quotaops.h> 34#include <asm/uaccess.h> 35#include "ext2.h" 36#include "xattr.h" 37#include "acl.h" 38 39static void ext2_sync_super(struct super_block *sb, 40 struct ext2_super_block *es, int wait); 41static int ext2_remount (struct super_block * sb, int * flags, char * data); 42static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf); 43static int ext2_sync_fs(struct super_block *sb, int wait); 44static int ext2_freeze(struct super_block *sb); 45static int ext2_unfreeze(struct super_block *sb); 46 47void ext2_error(struct super_block *sb, const char *function, 48 const char *fmt, ...) 49{ 50 struct va_format vaf; 51 va_list args; 52 struct ext2_sb_info *sbi = EXT2_SB(sb); 53 struct ext2_super_block *es = sbi->s_es; 54 55 if (!(sb->s_flags & MS_RDONLY)) { 56 spin_lock(&sbi->s_lock); 57 sbi->s_mount_state |= EXT2_ERROR_FS; 58 es->s_state |= cpu_to_le16(EXT2_ERROR_FS); 59 spin_unlock(&sbi->s_lock); 60 ext2_sync_super(sb, es, 1); 61 } 62 63 va_start(args, fmt); 64 65 vaf.fmt = fmt; 66 vaf.va = &args; 67 68 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n", 69 sb->s_id, function, &vaf); 70 71 va_end(args); 72 73 if (test_opt(sb, ERRORS_PANIC)) 74 panic("EXT2-fs: panic from previous error\n"); 75 if (test_opt(sb, ERRORS_RO)) { 76 ext2_msg(sb, KERN_CRIT, 77 "error: remounting filesystem read-only"); 78 sb->s_flags |= MS_RDONLY; 79 } 80} 81 82void ext2_msg(struct super_block *sb, const char *prefix, 83 const char *fmt, ...) 84{ 85 struct va_format vaf; 86 va_list args; 87 88 va_start(args, fmt); 89 90 vaf.fmt = fmt; 91 vaf.va = &args; 92 93 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf); 94 95 va_end(args); 96} 97 98/* 99 * This must be called with sbi->s_lock held. 100 */ 101void ext2_update_dynamic_rev(struct super_block *sb) 102{ 103 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 104 105 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) 106 return; 107 108 ext2_msg(sb, KERN_WARNING, 109 "warning: updating to rev %d because of " 110 "new feature flag, running e2fsck is recommended", 111 EXT2_DYNAMIC_REV); 112 113 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); 114 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); 115 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); 116 /* leave es->s_feature_*compat flags alone */ 117 /* es->s_uuid will be set by e2fsck if empty */ 118 119 /* 120 * The rest of the superblock fields should be zero, and if not it 121 * means they are likely already in use, so leave them alone. We 122 * can leave it up to e2fsck to clean up any inconsistencies there. 123 */ 124} 125 126static void ext2_put_super (struct super_block * sb) 127{ 128 int db_count; 129 int i; 130 struct ext2_sb_info *sbi = EXT2_SB(sb); 131 132 dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 133 134 ext2_xattr_put_super(sb); 135 if (!(sb->s_flags & MS_RDONLY)) { 136 struct ext2_super_block *es = sbi->s_es; 137 138 spin_lock(&sbi->s_lock); 139 es->s_state = cpu_to_le16(sbi->s_mount_state); 140 spin_unlock(&sbi->s_lock); 141 ext2_sync_super(sb, es, 1); 142 } 143 db_count = sbi->s_gdb_count; 144 for (i = 0; i < db_count; i++) 145 if (sbi->s_group_desc[i]) 146 brelse (sbi->s_group_desc[i]); 147 kfree(sbi->s_group_desc); 148 kfree(sbi->s_debts); 149 percpu_counter_destroy(&sbi->s_freeblocks_counter); 150 percpu_counter_destroy(&sbi->s_freeinodes_counter); 151 percpu_counter_destroy(&sbi->s_dirs_counter); 152 brelse (sbi->s_sbh); 153 sb->s_fs_info = NULL; 154 kfree(sbi->s_blockgroup_lock); 155 kfree(sbi); 156} 157 158static struct kmem_cache * ext2_inode_cachep; 159 160static struct inode *ext2_alloc_inode(struct super_block *sb) 161{ 162 struct ext2_inode_info *ei; 163 ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL); 164 if (!ei) 165 return NULL; 166 ei->i_block_alloc_info = NULL; 167 ei->vfs_inode.i_version = 1; 168#ifdef CONFIG_QUOTA 169 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot)); 170#endif 171 172 return &ei->vfs_inode; 173} 174 175static void ext2_i_callback(struct rcu_head *head) 176{ 177 struct inode *inode = container_of(head, struct inode, i_rcu); 178 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 179} 180 181static void ext2_destroy_inode(struct inode *inode) 182{ 183 call_rcu(&inode->i_rcu, ext2_i_callback); 184} 185 186static void init_once(void *foo) 187{ 188 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 189 190 rwlock_init(&ei->i_meta_lock); 191#ifdef CONFIG_EXT2_FS_XATTR 192 init_rwsem(&ei->xattr_sem); 193#endif 194 mutex_init(&ei->truncate_mutex); 195 inode_init_once(&ei->vfs_inode); 196} 197 198static int __init init_inodecache(void) 199{ 200 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 201 sizeof(struct ext2_inode_info), 202 0, (SLAB_RECLAIM_ACCOUNT| 203 SLAB_MEM_SPREAD), 204 init_once); 205 if (ext2_inode_cachep == NULL) 206 return -ENOMEM; 207 return 0; 208} 209 210static void destroy_inodecache(void) 211{ 212 /* 213 * Make sure all delayed rcu free inodes are flushed before we 214 * destroy cache. 215 */ 216 rcu_barrier(); 217 kmem_cache_destroy(ext2_inode_cachep); 218} 219 220static int ext2_show_options(struct seq_file *seq, struct dentry *root) 221{ 222 struct super_block *sb = root->d_sb; 223 struct ext2_sb_info *sbi = EXT2_SB(sb); 224 struct ext2_super_block *es = sbi->s_es; 225 unsigned long def_mount_opts; 226 227 spin_lock(&sbi->s_lock); 228 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 229 230 if (sbi->s_sb_block != 1) 231 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 232 if (test_opt(sb, MINIX_DF)) 233 seq_puts(seq, ",minixdf"); 234 if (test_opt(sb, GRPID)) 235 seq_puts(seq, ",grpid"); 236 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 237 seq_puts(seq, ",nogrpid"); 238 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) || 239 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 240 seq_printf(seq, ",resuid=%u", 241 from_kuid_munged(&init_user_ns, sbi->s_resuid)); 242 } 243 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) || 244 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 245 seq_printf(seq, ",resgid=%u", 246 from_kgid_munged(&init_user_ns, sbi->s_resgid)); 247 } 248 if (test_opt(sb, ERRORS_RO)) { 249 int def_errors = le16_to_cpu(es->s_errors); 250 251 if (def_errors == EXT2_ERRORS_PANIC || 252 def_errors == EXT2_ERRORS_CONTINUE) { 253 seq_puts(seq, ",errors=remount-ro"); 254 } 255 } 256 if (test_opt(sb, ERRORS_CONT)) 257 seq_puts(seq, ",errors=continue"); 258 if (test_opt(sb, ERRORS_PANIC)) 259 seq_puts(seq, ",errors=panic"); 260 if (test_opt(sb, NO_UID32)) 261 seq_puts(seq, ",nouid32"); 262 if (test_opt(sb, DEBUG)) 263 seq_puts(seq, ",debug"); 264 if (test_opt(sb, OLDALLOC)) 265 seq_puts(seq, ",oldalloc"); 266 267#ifdef CONFIG_EXT2_FS_XATTR 268 if (test_opt(sb, XATTR_USER)) 269 seq_puts(seq, ",user_xattr"); 270 if (!test_opt(sb, XATTR_USER) && 271 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 272 seq_puts(seq, ",nouser_xattr"); 273 } 274#endif 275 276#ifdef CONFIG_EXT2_FS_POSIX_ACL 277 if (test_opt(sb, POSIX_ACL)) 278 seq_puts(seq, ",acl"); 279 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 280 seq_puts(seq, ",noacl"); 281#endif 282 283 if (test_opt(sb, NOBH)) 284 seq_puts(seq, ",nobh"); 285 286#if defined(CONFIG_QUOTA) 287 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 288 seq_puts(seq, ",usrquota"); 289 290 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 291 seq_puts(seq, ",grpquota"); 292#endif 293 294#ifdef CONFIG_FS_DAX 295 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 296 seq_puts(seq, ",xip"); 297 if (sbi->s_mount_opt & EXT2_MOUNT_DAX) 298 seq_puts(seq, ",dax"); 299#endif 300 301 if (!test_opt(sb, RESERVATION)) 302 seq_puts(seq, ",noreservation"); 303 304 spin_unlock(&sbi->s_lock); 305 return 0; 306} 307 308#ifdef CONFIG_QUOTA 309static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 310static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 311static struct dquot **ext2_get_dquots(struct inode *inode) 312{ 313 return EXT2_I(inode)->i_dquot; 314} 315#endif 316 317static const struct super_operations ext2_sops = { 318 .alloc_inode = ext2_alloc_inode, 319 .destroy_inode = ext2_destroy_inode, 320 .write_inode = ext2_write_inode, 321 .evict_inode = ext2_evict_inode, 322 .put_super = ext2_put_super, 323 .sync_fs = ext2_sync_fs, 324 .freeze_fs = ext2_freeze, 325 .unfreeze_fs = ext2_unfreeze, 326 .statfs = ext2_statfs, 327 .remount_fs = ext2_remount, 328 .show_options = ext2_show_options, 329#ifdef CONFIG_QUOTA 330 .quota_read = ext2_quota_read, 331 .quota_write = ext2_quota_write, 332 .get_dquots = ext2_get_dquots, 333#endif 334}; 335 336static struct inode *ext2_nfs_get_inode(struct super_block *sb, 337 u64 ino, u32 generation) 338{ 339 struct inode *inode; 340 341 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 342 return ERR_PTR(-ESTALE); 343 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 344 return ERR_PTR(-ESTALE); 345 346 /* 347 * ext2_iget isn't quite right if the inode is currently unallocated! 348 * However ext2_iget currently does appropriate checks to handle stale 349 * inodes so everything is OK. 350 */ 351 inode = ext2_iget(sb, ino); 352 if (IS_ERR(inode)) 353 return ERR_CAST(inode); 354 if (generation && inode->i_generation != generation) { 355 /* we didn't find the right inode.. */ 356 iput(inode); 357 return ERR_PTR(-ESTALE); 358 } 359 return inode; 360} 361 362static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 363 int fh_len, int fh_type) 364{ 365 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 366 ext2_nfs_get_inode); 367} 368 369static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 370 int fh_len, int fh_type) 371{ 372 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 373 ext2_nfs_get_inode); 374} 375 376static const struct export_operations ext2_export_ops = { 377 .fh_to_dentry = ext2_fh_to_dentry, 378 .fh_to_parent = ext2_fh_to_parent, 379 .get_parent = ext2_get_parent, 380}; 381 382static unsigned long get_sb_block(void **data) 383{ 384 unsigned long sb_block; 385 char *options = (char *) *data; 386 387 if (!options || strncmp(options, "sb=", 3) != 0) 388 return 1; /* Default location */ 389 options += 3; 390 sb_block = simple_strtoul(options, &options, 0); 391 if (*options && *options != ',') { 392 printk("EXT2-fs: Invalid sb specification: %s\n", 393 (char *) *data); 394 return 1; 395 } 396 if (*options == ',') 397 options++; 398 *data = (void *) options; 399 return sb_block; 400} 401 402enum { 403 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 404 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 405 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 406 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 407 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota, 408 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 409}; 410 411static const match_table_t tokens = { 412 {Opt_bsd_df, "bsddf"}, 413 {Opt_minix_df, "minixdf"}, 414 {Opt_grpid, "grpid"}, 415 {Opt_grpid, "bsdgroups"}, 416 {Opt_nogrpid, "nogrpid"}, 417 {Opt_nogrpid, "sysvgroups"}, 418 {Opt_resgid, "resgid=%u"}, 419 {Opt_resuid, "resuid=%u"}, 420 {Opt_sb, "sb=%u"}, 421 {Opt_err_cont, "errors=continue"}, 422 {Opt_err_panic, "errors=panic"}, 423 {Opt_err_ro, "errors=remount-ro"}, 424 {Opt_nouid32, "nouid32"}, 425 {Opt_nocheck, "check=none"}, 426 {Opt_nocheck, "nocheck"}, 427 {Opt_debug, "debug"}, 428 {Opt_oldalloc, "oldalloc"}, 429 {Opt_orlov, "orlov"}, 430 {Opt_nobh, "nobh"}, 431 {Opt_user_xattr, "user_xattr"}, 432 {Opt_nouser_xattr, "nouser_xattr"}, 433 {Opt_acl, "acl"}, 434 {Opt_noacl, "noacl"}, 435 {Opt_xip, "xip"}, 436 {Opt_dax, "dax"}, 437 {Opt_grpquota, "grpquota"}, 438 {Opt_ignore, "noquota"}, 439 {Opt_quota, "quota"}, 440 {Opt_usrquota, "usrquota"}, 441 {Opt_reservation, "reservation"}, 442 {Opt_noreservation, "noreservation"}, 443 {Opt_err, NULL} 444}; 445 446static int parse_options(char *options, struct super_block *sb) 447{ 448 char *p; 449 struct ext2_sb_info *sbi = EXT2_SB(sb); 450 substring_t args[MAX_OPT_ARGS]; 451 int option; 452 kuid_t uid; 453 kgid_t gid; 454 455 if (!options) 456 return 1; 457 458 while ((p = strsep (&options, ",")) != NULL) { 459 int token; 460 if (!*p) 461 continue; 462 463 token = match_token(p, tokens, args); 464 switch (token) { 465 case Opt_bsd_df: 466 clear_opt (sbi->s_mount_opt, MINIX_DF); 467 break; 468 case Opt_minix_df: 469 set_opt (sbi->s_mount_opt, MINIX_DF); 470 break; 471 case Opt_grpid: 472 set_opt (sbi->s_mount_opt, GRPID); 473 break; 474 case Opt_nogrpid: 475 clear_opt (sbi->s_mount_opt, GRPID); 476 break; 477 case Opt_resuid: 478 if (match_int(&args[0], &option)) 479 return 0; 480 uid = make_kuid(current_user_ns(), option); 481 if (!uid_valid(uid)) { 482 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option); 483 return 0; 484 485 } 486 sbi->s_resuid = uid; 487 break; 488 case Opt_resgid: 489 if (match_int(&args[0], &option)) 490 return 0; 491 gid = make_kgid(current_user_ns(), option); 492 if (!gid_valid(gid)) { 493 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option); 494 return 0; 495 } 496 sbi->s_resgid = gid; 497 break; 498 case Opt_sb: 499 /* handled by get_sb_block() instead of here */ 500 /* *sb_block = match_int(&args[0]); */ 501 break; 502 case Opt_err_panic: 503 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 504 clear_opt (sbi->s_mount_opt, ERRORS_RO); 505 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 506 break; 507 case Opt_err_ro: 508 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 509 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 510 set_opt (sbi->s_mount_opt, ERRORS_RO); 511 break; 512 case Opt_err_cont: 513 clear_opt (sbi->s_mount_opt, ERRORS_RO); 514 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 515 set_opt (sbi->s_mount_opt, ERRORS_CONT); 516 break; 517 case Opt_nouid32: 518 set_opt (sbi->s_mount_opt, NO_UID32); 519 break; 520 case Opt_nocheck: 521 clear_opt (sbi->s_mount_opt, CHECK); 522 break; 523 case Opt_debug: 524 set_opt (sbi->s_mount_opt, DEBUG); 525 break; 526 case Opt_oldalloc: 527 set_opt (sbi->s_mount_opt, OLDALLOC); 528 break; 529 case Opt_orlov: 530 clear_opt (sbi->s_mount_opt, OLDALLOC); 531 break; 532 case Opt_nobh: 533 set_opt (sbi->s_mount_opt, NOBH); 534 break; 535#ifdef CONFIG_EXT2_FS_XATTR 536 case Opt_user_xattr: 537 set_opt (sbi->s_mount_opt, XATTR_USER); 538 break; 539 case Opt_nouser_xattr: 540 clear_opt (sbi->s_mount_opt, XATTR_USER); 541 break; 542#else 543 case Opt_user_xattr: 544 case Opt_nouser_xattr: 545 ext2_msg(sb, KERN_INFO, "(no)user_xattr options" 546 "not supported"); 547 break; 548#endif 549#ifdef CONFIG_EXT2_FS_POSIX_ACL 550 case Opt_acl: 551 set_opt(sbi->s_mount_opt, POSIX_ACL); 552 break; 553 case Opt_noacl: 554 clear_opt(sbi->s_mount_opt, POSIX_ACL); 555 break; 556#else 557 case Opt_acl: 558 case Opt_noacl: 559 ext2_msg(sb, KERN_INFO, 560 "(no)acl options not supported"); 561 break; 562#endif 563 case Opt_xip: 564 ext2_msg(sb, KERN_INFO, "use dax instead of xip"); 565 set_opt(sbi->s_mount_opt, XIP); 566 /* Fall through */ 567 case Opt_dax: 568#ifdef CONFIG_FS_DAX 569 set_opt(sbi->s_mount_opt, DAX); 570#else 571 ext2_msg(sb, KERN_INFO, "dax option not supported"); 572#endif 573 break; 574 575#if defined(CONFIG_QUOTA) 576 case Opt_quota: 577 case Opt_usrquota: 578 set_opt(sbi->s_mount_opt, USRQUOTA); 579 break; 580 581 case Opt_grpquota: 582 set_opt(sbi->s_mount_opt, GRPQUOTA); 583 break; 584#else 585 case Opt_quota: 586 case Opt_usrquota: 587 case Opt_grpquota: 588 ext2_msg(sb, KERN_INFO, 589 "quota operations not supported"); 590 break; 591#endif 592 593 case Opt_reservation: 594 set_opt(sbi->s_mount_opt, RESERVATION); 595 ext2_msg(sb, KERN_INFO, "reservations ON"); 596 break; 597 case Opt_noreservation: 598 clear_opt(sbi->s_mount_opt, RESERVATION); 599 ext2_msg(sb, KERN_INFO, "reservations OFF"); 600 break; 601 case Opt_ignore: 602 break; 603 default: 604 return 0; 605 } 606 } 607 return 1; 608} 609 610static int ext2_setup_super (struct super_block * sb, 611 struct ext2_super_block * es, 612 int read_only) 613{ 614 int res = 0; 615 struct ext2_sb_info *sbi = EXT2_SB(sb); 616 617 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 618 ext2_msg(sb, KERN_ERR, 619 "error: revision level too high, " 620 "forcing read-only mode"); 621 res = MS_RDONLY; 622 } 623 if (read_only) 624 return res; 625 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 626 ext2_msg(sb, KERN_WARNING, 627 "warning: mounting unchecked fs, " 628 "running e2fsck is recommended"); 629 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 630 ext2_msg(sb, KERN_WARNING, 631 "warning: mounting fs with errors, " 632 "running e2fsck is recommended"); 633 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 634 le16_to_cpu(es->s_mnt_count) >= 635 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 636 ext2_msg(sb, KERN_WARNING, 637 "warning: maximal mount count reached, " 638 "running e2fsck is recommended"); 639 else if (le32_to_cpu(es->s_checkinterval) && 640 (le32_to_cpu(es->s_lastcheck) + 641 le32_to_cpu(es->s_checkinterval) <= get_seconds())) 642 ext2_msg(sb, KERN_WARNING, 643 "warning: checktime reached, " 644 "running e2fsck is recommended"); 645 if (!le16_to_cpu(es->s_max_mnt_count)) 646 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 647 le16_add_cpu(&es->s_mnt_count, 1); 648 if (test_opt (sb, DEBUG)) 649 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, " 650 "bpg=%lu, ipg=%lu, mo=%04lx]", 651 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 652 sbi->s_frag_size, 653 sbi->s_groups_count, 654 EXT2_BLOCKS_PER_GROUP(sb), 655 EXT2_INODES_PER_GROUP(sb), 656 sbi->s_mount_opt); 657 return res; 658} 659 660static int ext2_check_descriptors(struct super_block *sb) 661{ 662 int i; 663 struct ext2_sb_info *sbi = EXT2_SB(sb); 664 665 ext2_debug ("Checking group descriptors"); 666 667 for (i = 0; i < sbi->s_groups_count; i++) { 668 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 669 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 670 ext2_fsblk_t last_block; 671 672 if (i == sbi->s_groups_count - 1) 673 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 674 else 675 last_block = first_block + 676 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 677 678 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 679 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 680 { 681 ext2_error (sb, "ext2_check_descriptors", 682 "Block bitmap for group %d" 683 " not in group (block %lu)!", 684 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 685 return 0; 686 } 687 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 688 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 689 { 690 ext2_error (sb, "ext2_check_descriptors", 691 "Inode bitmap for group %d" 692 " not in group (block %lu)!", 693 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 694 return 0; 695 } 696 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 697 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 698 last_block) 699 { 700 ext2_error (sb, "ext2_check_descriptors", 701 "Inode table for group %d" 702 " not in group (block %lu)!", 703 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 704 return 0; 705 } 706 } 707 return 1; 708} 709 710/* 711 * Maximal file size. There is a direct, and {,double-,triple-}indirect 712 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 713 * We need to be 1 filesystem block less than the 2^32 sector limit. 714 */ 715static loff_t ext2_max_size(int bits) 716{ 717 loff_t res = EXT2_NDIR_BLOCKS; 718 int meta_blocks; 719 loff_t upper_limit; 720 721 /* This is calculated to be the largest file size for a 722 * dense, file such that the total number of 723 * sectors in the file, including data and all indirect blocks, 724 * does not exceed 2^32 -1 725 * __u32 i_blocks representing the total number of 726 * 512 bytes blocks of the file 727 */ 728 upper_limit = (1LL << 32) - 1; 729 730 /* total blocks in file system block size */ 731 upper_limit >>= (bits - 9); 732 733 734 /* indirect blocks */ 735 meta_blocks = 1; 736 /* double indirect blocks */ 737 meta_blocks += 1 + (1LL << (bits-2)); 738 /* tripple indirect blocks */ 739 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2))); 740 741 upper_limit -= meta_blocks; 742 upper_limit <<= bits; 743 744 res += 1LL << (bits-2); 745 res += 1LL << (2*(bits-2)); 746 res += 1LL << (3*(bits-2)); 747 res <<= bits; 748 if (res > upper_limit) 749 res = upper_limit; 750 751 if (res > MAX_LFS_FILESIZE) 752 res = MAX_LFS_FILESIZE; 753 754 return res; 755} 756 757static unsigned long descriptor_loc(struct super_block *sb, 758 unsigned long logic_sb_block, 759 int nr) 760{ 761 struct ext2_sb_info *sbi = EXT2_SB(sb); 762 unsigned long bg, first_meta_bg; 763 int has_super = 0; 764 765 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 766 767 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 768 nr < first_meta_bg) 769 return (logic_sb_block + nr + 1); 770 bg = sbi->s_desc_per_block * nr; 771 if (ext2_bg_has_super(sb, bg)) 772 has_super = 1; 773 774 return ext2_group_first_block_no(sb, bg) + has_super; 775} 776 777static int ext2_fill_super(struct super_block *sb, void *data, int silent) 778{ 779 struct buffer_head * bh; 780 struct ext2_sb_info * sbi; 781 struct ext2_super_block * es; 782 struct inode *root; 783 unsigned long block; 784 unsigned long sb_block = get_sb_block(&data); 785 unsigned long logic_sb_block; 786 unsigned long offset = 0; 787 unsigned long def_mount_opts; 788 long ret = -EINVAL; 789 int blocksize = BLOCK_SIZE; 790 int db_count; 791 int i, j; 792 __le32 features; 793 int err; 794 795 err = -ENOMEM; 796 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 797 if (!sbi) 798 goto failed; 799 800 sbi->s_blockgroup_lock = 801 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 802 if (!sbi->s_blockgroup_lock) { 803 kfree(sbi); 804 goto failed; 805 } 806 sb->s_fs_info = sbi; 807 sbi->s_sb_block = sb_block; 808 809 spin_lock_init(&sbi->s_lock); 810 811 /* 812 * See what the current blocksize for the device is, and 813 * use that as the blocksize. Otherwise (or if the blocksize 814 * is smaller than the default) use the default. 815 * This is important for devices that have a hardware 816 * sectorsize that is larger than the default. 817 */ 818 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 819 if (!blocksize) { 820 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 821 goto failed_sbi; 822 } 823 824 /* 825 * If the superblock doesn't start on a hardware sector boundary, 826 * calculate the offset. 827 */ 828 if (blocksize != BLOCK_SIZE) { 829 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 830 offset = (sb_block*BLOCK_SIZE) % blocksize; 831 } else { 832 logic_sb_block = sb_block; 833 } 834 835 if (!(bh = sb_bread(sb, logic_sb_block))) { 836 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 837 goto failed_sbi; 838 } 839 /* 840 * Note: s_es must be initialized as soon as possible because 841 * some ext2 macro-instructions depend on its value 842 */ 843 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 844 sbi->s_es = es; 845 sb->s_magic = le16_to_cpu(es->s_magic); 846 847 if (sb->s_magic != EXT2_SUPER_MAGIC) 848 goto cantfind_ext2; 849 850 /* Set defaults before we parse the mount options */ 851 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 852 if (def_mount_opts & EXT2_DEFM_DEBUG) 853 set_opt(sbi->s_mount_opt, DEBUG); 854 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 855 set_opt(sbi->s_mount_opt, GRPID); 856 if (def_mount_opts & EXT2_DEFM_UID16) 857 set_opt(sbi->s_mount_opt, NO_UID32); 858#ifdef CONFIG_EXT2_FS_XATTR 859 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 860 set_opt(sbi->s_mount_opt, XATTR_USER); 861#endif 862#ifdef CONFIG_EXT2_FS_POSIX_ACL 863 if (def_mount_opts & EXT2_DEFM_ACL) 864 set_opt(sbi->s_mount_opt, POSIX_ACL); 865#endif 866 867 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 868 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 869 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 870 set_opt(sbi->s_mount_opt, ERRORS_CONT); 871 else 872 set_opt(sbi->s_mount_opt, ERRORS_RO); 873 874 sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid)); 875 sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid)); 876 877 set_opt(sbi->s_mount_opt, RESERVATION); 878 879 if (!parse_options((char *) data, sb)) 880 goto failed_mount; 881 882 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 883 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 884 MS_POSIXACL : 0); 885 886 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 887 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 888 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 889 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 890 ext2_msg(sb, KERN_WARNING, 891 "warning: feature flags set on rev 0 fs, " 892 "running e2fsck is recommended"); 893 /* 894 * Check feature flags regardless of the revision level, since we 895 * previously didn't change the revision level when setting the flags, 896 * so there is a chance incompat flags are set on a rev 0 filesystem. 897 */ 898 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 899 if (features) { 900 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 901 "unsupported optional features (%x)", 902 le32_to_cpu(features)); 903 goto failed_mount; 904 } 905 if (!(sb->s_flags & MS_RDONLY) && 906 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 907 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 908 "unsupported optional features (%x)", 909 le32_to_cpu(features)); 910 goto failed_mount; 911 } 912 913 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 914 915 if (sbi->s_mount_opt & EXT2_MOUNT_DAX) { 916 if (blocksize != PAGE_SIZE) { 917 ext2_msg(sb, KERN_ERR, 918 "error: unsupported blocksize for dax"); 919 goto failed_mount; 920 } 921 if (!sb->s_bdev->bd_disk->fops->direct_access) { 922 ext2_msg(sb, KERN_ERR, 923 "error: device does not support dax"); 924 goto failed_mount; 925 } 926 } 927 928 /* If the blocksize doesn't match, re-read the thing.. */ 929 if (sb->s_blocksize != blocksize) { 930 brelse(bh); 931 932 if (!sb_set_blocksize(sb, blocksize)) { 933 ext2_msg(sb, KERN_ERR, 934 "error: bad blocksize %d", blocksize); 935 goto failed_sbi; 936 } 937 938 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 939 offset = (sb_block*BLOCK_SIZE) % blocksize; 940 bh = sb_bread(sb, logic_sb_block); 941 if(!bh) { 942 ext2_msg(sb, KERN_ERR, "error: couldn't read" 943 "superblock on 2nd try"); 944 goto failed_sbi; 945 } 946 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 947 sbi->s_es = es; 948 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 949 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 950 goto failed_mount; 951 } 952 } 953 954 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 955 sb->s_max_links = EXT2_LINK_MAX; 956 957 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 958 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 959 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 960 } else { 961 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 962 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 963 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 964 !is_power_of_2(sbi->s_inode_size) || 965 (sbi->s_inode_size > blocksize)) { 966 ext2_msg(sb, KERN_ERR, 967 "error: unsupported inode size: %d", 968 sbi->s_inode_size); 969 goto failed_mount; 970 } 971 } 972 973 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 974 le32_to_cpu(es->s_log_frag_size); 975 if (sbi->s_frag_size == 0) 976 goto cantfind_ext2; 977 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 978 979 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 980 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 981 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 982 983 if (EXT2_INODE_SIZE(sb) == 0) 984 goto cantfind_ext2; 985 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 986 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 987 goto cantfind_ext2; 988 sbi->s_itb_per_group = sbi->s_inodes_per_group / 989 sbi->s_inodes_per_block; 990 sbi->s_desc_per_block = sb->s_blocksize / 991 sizeof (struct ext2_group_desc); 992 sbi->s_sbh = bh; 993 sbi->s_mount_state = le16_to_cpu(es->s_state); 994 sbi->s_addr_per_block_bits = 995 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 996 sbi->s_desc_per_block_bits = 997 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 998 999 if (sb->s_magic != EXT2_SUPER_MAGIC) 1000 goto cantfind_ext2; 1001 1002 if (sb->s_blocksize != bh->b_size) { 1003 if (!silent) 1004 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 1005 goto failed_mount; 1006 } 1007 1008 if (sb->s_blocksize != sbi->s_frag_size) { 1009 ext2_msg(sb, KERN_ERR, 1010 "error: fragsize %lu != blocksize %lu" 1011 "(not supported yet)", 1012 sbi->s_frag_size, sb->s_blocksize); 1013 goto failed_mount; 1014 } 1015 1016 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 1017 ext2_msg(sb, KERN_ERR, 1018 "error: #blocks per group too big: %lu", 1019 sbi->s_blocks_per_group); 1020 goto failed_mount; 1021 } 1022 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 1023 ext2_msg(sb, KERN_ERR, 1024 "error: #fragments per group too big: %lu", 1025 sbi->s_frags_per_group); 1026 goto failed_mount; 1027 } 1028 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 1029 ext2_msg(sb, KERN_ERR, 1030 "error: #inodes per group too big: %lu", 1031 sbi->s_inodes_per_group); 1032 goto failed_mount; 1033 } 1034 1035 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 1036 goto cantfind_ext2; 1037 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1038 le32_to_cpu(es->s_first_data_block) - 1) 1039 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1040 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1041 EXT2_DESC_PER_BLOCK(sb); 1042 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 1043 if (sbi->s_group_desc == NULL) { 1044 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1045 goto failed_mount; 1046 } 1047 bgl_lock_init(sbi->s_blockgroup_lock); 1048 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1049 if (!sbi->s_debts) { 1050 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1051 goto failed_mount_group_desc; 1052 } 1053 for (i = 0; i < db_count; i++) { 1054 block = descriptor_loc(sb, logic_sb_block, i); 1055 sbi->s_group_desc[i] = sb_bread(sb, block); 1056 if (!sbi->s_group_desc[i]) { 1057 for (j = 0; j < i; j++) 1058 brelse (sbi->s_group_desc[j]); 1059 ext2_msg(sb, KERN_ERR, 1060 "error: unable to read group descriptors"); 1061 goto failed_mount_group_desc; 1062 } 1063 } 1064 if (!ext2_check_descriptors (sb)) { 1065 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1066 goto failed_mount2; 1067 } 1068 sbi->s_gdb_count = db_count; 1069 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1070 spin_lock_init(&sbi->s_next_gen_lock); 1071 1072 /* per fileystem reservation list head & lock */ 1073 spin_lock_init(&sbi->s_rsv_window_lock); 1074 sbi->s_rsv_window_root = RB_ROOT; 1075 /* 1076 * Add a single, static dummy reservation to the start of the 1077 * reservation window list --- it gives us a placeholder for 1078 * append-at-start-of-list which makes the allocation logic 1079 * _much_ simpler. 1080 */ 1081 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1082 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1083 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1084 sbi->s_rsv_window_head.rsv_goal_size = 0; 1085 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1086 1087 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1088 ext2_count_free_blocks(sb), GFP_KERNEL); 1089 if (!err) { 1090 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1091 ext2_count_free_inodes(sb), GFP_KERNEL); 1092 } 1093 if (!err) { 1094 err = percpu_counter_init(&sbi->s_dirs_counter, 1095 ext2_count_dirs(sb), GFP_KERNEL); 1096 } 1097 if (err) { 1098 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1099 goto failed_mount3; 1100 } 1101 /* 1102 * set up enough so that it can read an inode 1103 */ 1104 sb->s_op = &ext2_sops; 1105 sb->s_export_op = &ext2_export_ops; 1106 sb->s_xattr = ext2_xattr_handlers; 1107 1108#ifdef CONFIG_QUOTA 1109 sb->dq_op = &dquot_operations; 1110 sb->s_qcop = &dquot_quotactl_ops; 1111 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP; 1112#endif 1113 1114 root = ext2_iget(sb, EXT2_ROOT_INO); 1115 if (IS_ERR(root)) { 1116 ret = PTR_ERR(root); 1117 goto failed_mount3; 1118 } 1119 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1120 iput(root); 1121 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1122 goto failed_mount3; 1123 } 1124 1125 sb->s_root = d_make_root(root); 1126 if (!sb->s_root) { 1127 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1128 ret = -ENOMEM; 1129 goto failed_mount3; 1130 } 1131 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1132 ext2_msg(sb, KERN_WARNING, 1133 "warning: mounting ext3 filesystem as ext2"); 1134 if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY)) 1135 sb->s_flags |= MS_RDONLY; 1136 ext2_write_super(sb); 1137 return 0; 1138 1139cantfind_ext2: 1140 if (!silent) 1141 ext2_msg(sb, KERN_ERR, 1142 "error: can't find an ext2 filesystem on dev %s.", 1143 sb->s_id); 1144 goto failed_mount; 1145failed_mount3: 1146 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1147 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1148 percpu_counter_destroy(&sbi->s_dirs_counter); 1149failed_mount2: 1150 for (i = 0; i < db_count; i++) 1151 brelse(sbi->s_group_desc[i]); 1152failed_mount_group_desc: 1153 kfree(sbi->s_group_desc); 1154 kfree(sbi->s_debts); 1155failed_mount: 1156 brelse(bh); 1157failed_sbi: 1158 sb->s_fs_info = NULL; 1159 kfree(sbi->s_blockgroup_lock); 1160 kfree(sbi); 1161failed: 1162 return ret; 1163} 1164 1165static void ext2_clear_super_error(struct super_block *sb) 1166{ 1167 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1168 1169 if (buffer_write_io_error(sbh)) { 1170 /* 1171 * Oh, dear. A previous attempt to write the 1172 * superblock failed. This could happen because the 1173 * USB device was yanked out. Or it could happen to 1174 * be a transient write error and maybe the block will 1175 * be remapped. Nothing we can do but to retry the 1176 * write and hope for the best. 1177 */ 1178 ext2_msg(sb, KERN_ERR, 1179 "previous I/O error to superblock detected\n"); 1180 clear_buffer_write_io_error(sbh); 1181 set_buffer_uptodate(sbh); 1182 } 1183} 1184 1185static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, 1186 int wait) 1187{ 1188 ext2_clear_super_error(sb); 1189 spin_lock(&EXT2_SB(sb)->s_lock); 1190 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1191 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1192 es->s_wtime = cpu_to_le32(get_seconds()); 1193 /* unlock before we do IO */ 1194 spin_unlock(&EXT2_SB(sb)->s_lock); 1195 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1196 if (wait) 1197 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1198} 1199 1200/* 1201 * In the second extended file system, it is not necessary to 1202 * write the super block since we use a mapping of the 1203 * disk super block in a buffer. 1204 * 1205 * However, this function is still used to set the fs valid 1206 * flags to 0. We need to set this flag to 0 since the fs 1207 * may have been checked while mounted and e2fsck may have 1208 * set s_state to EXT2_VALID_FS after some corrections. 1209 */ 1210static int ext2_sync_fs(struct super_block *sb, int wait) 1211{ 1212 struct ext2_sb_info *sbi = EXT2_SB(sb); 1213 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1214 1215 /* 1216 * Write quota structures to quota file, sync_blockdev() will write 1217 * them to disk later 1218 */ 1219 dquot_writeback_dquots(sb, -1); 1220 1221 spin_lock(&sbi->s_lock); 1222 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1223 ext2_debug("setting valid to 0\n"); 1224 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1225 } 1226 spin_unlock(&sbi->s_lock); 1227 ext2_sync_super(sb, es, wait); 1228 return 0; 1229} 1230 1231static int ext2_freeze(struct super_block *sb) 1232{ 1233 struct ext2_sb_info *sbi = EXT2_SB(sb); 1234 1235 /* 1236 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared 1237 * because we have unattached inodes and thus filesystem is not fully 1238 * consistent. 1239 */ 1240 if (atomic_long_read(&sb->s_remove_count)) { 1241 ext2_sync_fs(sb, 1); 1242 return 0; 1243 } 1244 /* Set EXT2_FS_VALID flag */ 1245 spin_lock(&sbi->s_lock); 1246 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); 1247 spin_unlock(&sbi->s_lock); 1248 ext2_sync_super(sb, sbi->s_es, 1); 1249 1250 return 0; 1251} 1252 1253static int ext2_unfreeze(struct super_block *sb) 1254{ 1255 /* Just write sb to clear EXT2_VALID_FS flag */ 1256 ext2_write_super(sb); 1257 1258 return 0; 1259} 1260 1261void ext2_write_super(struct super_block *sb) 1262{ 1263 if (!(sb->s_flags & MS_RDONLY)) 1264 ext2_sync_fs(sb, 1); 1265} 1266 1267static int ext2_remount (struct super_block * sb, int * flags, char * data) 1268{ 1269 struct ext2_sb_info * sbi = EXT2_SB(sb); 1270 struct ext2_super_block * es; 1271 struct ext2_mount_options old_opts; 1272 unsigned long old_sb_flags; 1273 int err; 1274 1275 sync_filesystem(sb); 1276 spin_lock(&sbi->s_lock); 1277 1278 /* Store the old options */ 1279 old_sb_flags = sb->s_flags; 1280 old_opts.s_mount_opt = sbi->s_mount_opt; 1281 old_opts.s_resuid = sbi->s_resuid; 1282 old_opts.s_resgid = sbi->s_resgid; 1283 1284 /* 1285 * Allow the "check" option to be passed as a remount option. 1286 */ 1287 if (!parse_options(data, sb)) { 1288 err = -EINVAL; 1289 goto restore_opts; 1290 } 1291 1292 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1293 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1294 1295 es = sbi->s_es; 1296 if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT2_MOUNT_DAX) { 1297 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1298 "dax flag with busy inodes while remounting"); 1299 sbi->s_mount_opt ^= EXT2_MOUNT_DAX; 1300 } 1301 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { 1302 spin_unlock(&sbi->s_lock); 1303 return 0; 1304 } 1305 if (*flags & MS_RDONLY) { 1306 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1307 !(sbi->s_mount_state & EXT2_VALID_FS)) { 1308 spin_unlock(&sbi->s_lock); 1309 return 0; 1310 } 1311 1312 /* 1313 * OK, we are remounting a valid rw partition rdonly, so set 1314 * the rdonly flag and then mark the partition as valid again. 1315 */ 1316 es->s_state = cpu_to_le16(sbi->s_mount_state); 1317 es->s_mtime = cpu_to_le32(get_seconds()); 1318 spin_unlock(&sbi->s_lock); 1319 1320 err = dquot_suspend(sb, -1); 1321 if (err < 0) { 1322 spin_lock(&sbi->s_lock); 1323 goto restore_opts; 1324 } 1325 1326 ext2_sync_super(sb, es, 1); 1327 } else { 1328 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1329 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1330 if (ret) { 1331 ext2_msg(sb, KERN_WARNING, 1332 "warning: couldn't remount RDWR because of " 1333 "unsupported optional features (%x).", 1334 le32_to_cpu(ret)); 1335 err = -EROFS; 1336 goto restore_opts; 1337 } 1338 /* 1339 * Mounting a RDONLY partition read-write, so reread and 1340 * store the current valid flag. (It may have been changed 1341 * by e2fsck since we originally mounted the partition.) 1342 */ 1343 sbi->s_mount_state = le16_to_cpu(es->s_state); 1344 if (!ext2_setup_super (sb, es, 0)) 1345 sb->s_flags &= ~MS_RDONLY; 1346 spin_unlock(&sbi->s_lock); 1347 1348 ext2_write_super(sb); 1349 1350 dquot_resume(sb, -1); 1351 } 1352 1353 return 0; 1354restore_opts: 1355 sbi->s_mount_opt = old_opts.s_mount_opt; 1356 sbi->s_resuid = old_opts.s_resuid; 1357 sbi->s_resgid = old_opts.s_resgid; 1358 sb->s_flags = old_sb_flags; 1359 spin_unlock(&sbi->s_lock); 1360 return err; 1361} 1362 1363static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1364{ 1365 struct super_block *sb = dentry->d_sb; 1366 struct ext2_sb_info *sbi = EXT2_SB(sb); 1367 struct ext2_super_block *es = sbi->s_es; 1368 u64 fsid; 1369 1370 spin_lock(&sbi->s_lock); 1371 1372 if (test_opt (sb, MINIX_DF)) 1373 sbi->s_overhead_last = 0; 1374 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1375 unsigned long i, overhead = 0; 1376 smp_rmb(); 1377 1378 /* 1379 * Compute the overhead (FS structures). This is constant 1380 * for a given filesystem unless the number of block groups 1381 * changes so we cache the previous value until it does. 1382 */ 1383 1384 /* 1385 * All of the blocks before first_data_block are 1386 * overhead 1387 */ 1388 overhead = le32_to_cpu(es->s_first_data_block); 1389 1390 /* 1391 * Add the overhead attributed to the superblock and 1392 * block group descriptors. If the sparse superblocks 1393 * feature is turned on, then not all groups have this. 1394 */ 1395 for (i = 0; i < sbi->s_groups_count; i++) 1396 overhead += ext2_bg_has_super(sb, i) + 1397 ext2_bg_num_gdb(sb, i); 1398 1399 /* 1400 * Every block group has an inode bitmap, a block 1401 * bitmap, and an inode table. 1402 */ 1403 overhead += (sbi->s_groups_count * 1404 (2 + sbi->s_itb_per_group)); 1405 sbi->s_overhead_last = overhead; 1406 smp_wmb(); 1407 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1408 } 1409 1410 buf->f_type = EXT2_SUPER_MAGIC; 1411 buf->f_bsize = sb->s_blocksize; 1412 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1413 buf->f_bfree = ext2_count_free_blocks(sb); 1414 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1415 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1416 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1417 buf->f_bavail = 0; 1418 buf->f_files = le32_to_cpu(es->s_inodes_count); 1419 buf->f_ffree = ext2_count_free_inodes(sb); 1420 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1421 buf->f_namelen = EXT2_NAME_LEN; 1422 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1423 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1424 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1425 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1426 spin_unlock(&sbi->s_lock); 1427 return 0; 1428} 1429 1430static struct dentry *ext2_mount(struct file_system_type *fs_type, 1431 int flags, const char *dev_name, void *data) 1432{ 1433 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1434} 1435 1436#ifdef CONFIG_QUOTA 1437 1438/* Read data from quotafile - avoid pagecache and such because we cannot afford 1439 * acquiring the locks... As quota files are never truncated and quota code 1440 * itself serializes the operations (and no one else should touch the files) 1441 * we don't have to be afraid of races */ 1442static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1443 size_t len, loff_t off) 1444{ 1445 struct inode *inode = sb_dqopt(sb)->files[type]; 1446 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1447 int err = 0; 1448 int offset = off & (sb->s_blocksize - 1); 1449 int tocopy; 1450 size_t toread; 1451 struct buffer_head tmp_bh; 1452 struct buffer_head *bh; 1453 loff_t i_size = i_size_read(inode); 1454 1455 if (off > i_size) 1456 return 0; 1457 if (off+len > i_size) 1458 len = i_size-off; 1459 toread = len; 1460 while (toread > 0) { 1461 tocopy = sb->s_blocksize - offset < toread ? 1462 sb->s_blocksize - offset : toread; 1463 1464 tmp_bh.b_state = 0; 1465 tmp_bh.b_size = sb->s_blocksize; 1466 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1467 if (err < 0) 1468 return err; 1469 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1470 memset(data, 0, tocopy); 1471 else { 1472 bh = sb_bread(sb, tmp_bh.b_blocknr); 1473 if (!bh) 1474 return -EIO; 1475 memcpy(data, bh->b_data+offset, tocopy); 1476 brelse(bh); 1477 } 1478 offset = 0; 1479 toread -= tocopy; 1480 data += tocopy; 1481 blk++; 1482 } 1483 return len; 1484} 1485 1486/* Write to quotafile */ 1487static ssize_t ext2_quota_write(struct super_block *sb, int type, 1488 const char *data, size_t len, loff_t off) 1489{ 1490 struct inode *inode = sb_dqopt(sb)->files[type]; 1491 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1492 int err = 0; 1493 int offset = off & (sb->s_blocksize - 1); 1494 int tocopy; 1495 size_t towrite = len; 1496 struct buffer_head tmp_bh; 1497 struct buffer_head *bh; 1498 1499 while (towrite > 0) { 1500 tocopy = sb->s_blocksize - offset < towrite ? 1501 sb->s_blocksize - offset : towrite; 1502 1503 tmp_bh.b_state = 0; 1504 tmp_bh.b_size = sb->s_blocksize; 1505 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1506 if (err < 0) 1507 goto out; 1508 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1509 bh = sb_bread(sb, tmp_bh.b_blocknr); 1510 else 1511 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1512 if (unlikely(!bh)) { 1513 err = -EIO; 1514 goto out; 1515 } 1516 lock_buffer(bh); 1517 memcpy(bh->b_data+offset, data, tocopy); 1518 flush_dcache_page(bh->b_page); 1519 set_buffer_uptodate(bh); 1520 mark_buffer_dirty(bh); 1521 unlock_buffer(bh); 1522 brelse(bh); 1523 offset = 0; 1524 towrite -= tocopy; 1525 data += tocopy; 1526 blk++; 1527 } 1528out: 1529 if (len == towrite) 1530 return err; 1531 if (inode->i_size < off+len-towrite) 1532 i_size_write(inode, off+len-towrite); 1533 inode->i_version++; 1534 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1535 mark_inode_dirty(inode); 1536 return len - towrite; 1537} 1538 1539#endif 1540 1541static struct file_system_type ext2_fs_type = { 1542 .owner = THIS_MODULE, 1543 .name = "ext2", 1544 .mount = ext2_mount, 1545 .kill_sb = kill_block_super, 1546 .fs_flags = FS_REQUIRES_DEV, 1547}; 1548MODULE_ALIAS_FS("ext2"); 1549 1550static int __init init_ext2_fs(void) 1551{ 1552 int err = init_ext2_xattr(); 1553 if (err) 1554 return err; 1555 err = init_inodecache(); 1556 if (err) 1557 goto out1; 1558 err = register_filesystem(&ext2_fs_type); 1559 if (err) 1560 goto out; 1561 return 0; 1562out: 1563 destroy_inodecache(); 1564out1: 1565 exit_ext2_xattr(); 1566 return err; 1567} 1568 1569static void __exit exit_ext2_fs(void) 1570{ 1571 unregister_filesystem(&ext2_fs_type); 1572 destroy_inodecache(); 1573 exit_ext2_xattr(); 1574} 1575 1576MODULE_AUTHOR("Remy Card and others"); 1577MODULE_DESCRIPTION("Second Extended Filesystem"); 1578MODULE_LICENSE("GPL"); 1579module_init(init_ext2_fs) 1580module_exit(exit_ext2_fs) 1581