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 #include "xip.h" 39 40 static void ext2_sync_super(struct super_block *sb, 41 struct ext2_super_block *es, int wait); 42 static int ext2_remount (struct super_block * sb, int * flags, char * data); 43 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf); 44 static int ext2_sync_fs(struct super_block *sb, int wait); 45 static int ext2_freeze(struct super_block *sb); 46 static int ext2_unfreeze(struct super_block *sb); 47 48 void ext2_error(struct super_block *sb, const char *function, 49 const char *fmt, ...) 50 { 51 struct va_format vaf; 52 va_list args; 53 struct ext2_sb_info *sbi = EXT2_SB(sb); 54 struct ext2_super_block *es = sbi->s_es; 55 56 if (!(sb->s_flags & MS_RDONLY)) { 57 spin_lock(&sbi->s_lock); 58 sbi->s_mount_state |= EXT2_ERROR_FS; 59 es->s_state |= cpu_to_le16(EXT2_ERROR_FS); 60 spin_unlock(&sbi->s_lock); 61 ext2_sync_super(sb, es, 1); 62 } 63 64 va_start(args, fmt); 65 66 vaf.fmt = fmt; 67 vaf.va = &args; 68 69 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n", 70 sb->s_id, function, &vaf); 71 72 va_end(args); 73 74 if (test_opt(sb, ERRORS_PANIC)) 75 panic("EXT2-fs: panic from previous error\n"); 76 if (test_opt(sb, ERRORS_RO)) { 77 ext2_msg(sb, KERN_CRIT, 78 "error: remounting filesystem read-only"); 79 sb->s_flags |= MS_RDONLY; 80 } 81 } 82 83 void ext2_msg(struct super_block *sb, const char *prefix, 84 const char *fmt, ...) 85 { 86 struct va_format vaf; 87 va_list args; 88 89 va_start(args, fmt); 90 91 vaf.fmt = fmt; 92 vaf.va = &args; 93 94 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf); 95 96 va_end(args); 97 } 98 99 /* 100 * This must be called with sbi->s_lock held. 101 */ 102 void ext2_update_dynamic_rev(struct super_block *sb) 103 { 104 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 105 106 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) 107 return; 108 109 ext2_msg(sb, KERN_WARNING, 110 "warning: updating to rev %d because of " 111 "new feature flag, running e2fsck is recommended", 112 EXT2_DYNAMIC_REV); 113 114 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); 115 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); 116 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); 117 /* leave es->s_feature_*compat flags alone */ 118 /* es->s_uuid will be set by e2fsck if empty */ 119 120 /* 121 * The rest of the superblock fields should be zero, and if not it 122 * means they are likely already in use, so leave them alone. We 123 * can leave it up to e2fsck to clean up any inconsistencies there. 124 */ 125 } 126 127 static void ext2_put_super (struct super_block * sb) 128 { 129 int db_count; 130 int i; 131 struct ext2_sb_info *sbi = EXT2_SB(sb); 132 133 dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); 134 135 ext2_xattr_put_super(sb); 136 if (!(sb->s_flags & MS_RDONLY)) { 137 struct ext2_super_block *es = sbi->s_es; 138 139 spin_lock(&sbi->s_lock); 140 es->s_state = cpu_to_le16(sbi->s_mount_state); 141 spin_unlock(&sbi->s_lock); 142 ext2_sync_super(sb, es, 1); 143 } 144 db_count = sbi->s_gdb_count; 145 for (i = 0; i < db_count; i++) 146 if (sbi->s_group_desc[i]) 147 brelse (sbi->s_group_desc[i]); 148 kfree(sbi->s_group_desc); 149 kfree(sbi->s_debts); 150 percpu_counter_destroy(&sbi->s_freeblocks_counter); 151 percpu_counter_destroy(&sbi->s_freeinodes_counter); 152 percpu_counter_destroy(&sbi->s_dirs_counter); 153 brelse (sbi->s_sbh); 154 sb->s_fs_info = NULL; 155 kfree(sbi->s_blockgroup_lock); 156 kfree(sbi); 157 } 158 159 static struct kmem_cache * ext2_inode_cachep; 160 161 static struct inode *ext2_alloc_inode(struct super_block *sb) 162 { 163 struct ext2_inode_info *ei; 164 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL); 165 if (!ei) 166 return NULL; 167 ei->i_block_alloc_info = NULL; 168 ei->vfs_inode.i_version = 1; 169 return &ei->vfs_inode; 170 } 171 172 static void ext2_i_callback(struct rcu_head *head) 173 { 174 struct inode *inode = container_of(head, struct inode, i_rcu); 175 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 176 } 177 178 static void ext2_destroy_inode(struct inode *inode) 179 { 180 call_rcu(&inode->i_rcu, ext2_i_callback); 181 } 182 183 static void init_once(void *foo) 184 { 185 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 186 187 rwlock_init(&ei->i_meta_lock); 188 #ifdef CONFIG_EXT2_FS_XATTR 189 init_rwsem(&ei->xattr_sem); 190 #endif 191 mutex_init(&ei->truncate_mutex); 192 inode_init_once(&ei->vfs_inode); 193 } 194 195 static int init_inodecache(void) 196 { 197 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 198 sizeof(struct ext2_inode_info), 199 0, (SLAB_RECLAIM_ACCOUNT| 200 SLAB_MEM_SPREAD), 201 init_once); 202 if (ext2_inode_cachep == NULL) 203 return -ENOMEM; 204 return 0; 205 } 206 207 static void destroy_inodecache(void) 208 { 209 /* 210 * Make sure all delayed rcu free inodes are flushed before we 211 * destroy cache. 212 */ 213 rcu_barrier(); 214 kmem_cache_destroy(ext2_inode_cachep); 215 } 216 217 static int ext2_show_options(struct seq_file *seq, struct dentry *root) 218 { 219 struct super_block *sb = root->d_sb; 220 struct ext2_sb_info *sbi = EXT2_SB(sb); 221 struct ext2_super_block *es = sbi->s_es; 222 unsigned long def_mount_opts; 223 224 spin_lock(&sbi->s_lock); 225 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 226 227 if (sbi->s_sb_block != 1) 228 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 229 if (test_opt(sb, MINIX_DF)) 230 seq_puts(seq, ",minixdf"); 231 if (test_opt(sb, GRPID)) 232 seq_puts(seq, ",grpid"); 233 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 234 seq_puts(seq, ",nogrpid"); 235 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) || 236 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 237 seq_printf(seq, ",resuid=%u", 238 from_kuid_munged(&init_user_ns, sbi->s_resuid)); 239 } 240 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) || 241 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 242 seq_printf(seq, ",resgid=%u", 243 from_kgid_munged(&init_user_ns, sbi->s_resgid)); 244 } 245 if (test_opt(sb, ERRORS_RO)) { 246 int def_errors = le16_to_cpu(es->s_errors); 247 248 if (def_errors == EXT2_ERRORS_PANIC || 249 def_errors == EXT2_ERRORS_CONTINUE) { 250 seq_puts(seq, ",errors=remount-ro"); 251 } 252 } 253 if (test_opt(sb, ERRORS_CONT)) 254 seq_puts(seq, ",errors=continue"); 255 if (test_opt(sb, ERRORS_PANIC)) 256 seq_puts(seq, ",errors=panic"); 257 if (test_opt(sb, NO_UID32)) 258 seq_puts(seq, ",nouid32"); 259 if (test_opt(sb, DEBUG)) 260 seq_puts(seq, ",debug"); 261 if (test_opt(sb, OLDALLOC)) 262 seq_puts(seq, ",oldalloc"); 263 264 #ifdef CONFIG_EXT2_FS_XATTR 265 if (test_opt(sb, XATTR_USER)) 266 seq_puts(seq, ",user_xattr"); 267 if (!test_opt(sb, XATTR_USER) && 268 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 269 seq_puts(seq, ",nouser_xattr"); 270 } 271 #endif 272 273 #ifdef CONFIG_EXT2_FS_POSIX_ACL 274 if (test_opt(sb, POSIX_ACL)) 275 seq_puts(seq, ",acl"); 276 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 277 seq_puts(seq, ",noacl"); 278 #endif 279 280 if (test_opt(sb, NOBH)) 281 seq_puts(seq, ",nobh"); 282 283 #if defined(CONFIG_QUOTA) 284 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 285 seq_puts(seq, ",usrquota"); 286 287 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 288 seq_puts(seq, ",grpquota"); 289 #endif 290 291 #if defined(CONFIG_EXT2_FS_XIP) 292 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 293 seq_puts(seq, ",xip"); 294 #endif 295 296 if (!test_opt(sb, RESERVATION)) 297 seq_puts(seq, ",noreservation"); 298 299 spin_unlock(&sbi->s_lock); 300 return 0; 301 } 302 303 #ifdef CONFIG_QUOTA 304 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 305 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 306 #endif 307 308 static const struct super_operations ext2_sops = { 309 .alloc_inode = ext2_alloc_inode, 310 .destroy_inode = ext2_destroy_inode, 311 .write_inode = ext2_write_inode, 312 .evict_inode = ext2_evict_inode, 313 .put_super = ext2_put_super, 314 .sync_fs = ext2_sync_fs, 315 .freeze_fs = ext2_freeze, 316 .unfreeze_fs = ext2_unfreeze, 317 .statfs = ext2_statfs, 318 .remount_fs = ext2_remount, 319 .show_options = ext2_show_options, 320 #ifdef CONFIG_QUOTA 321 .quota_read = ext2_quota_read, 322 .quota_write = ext2_quota_write, 323 #endif 324 }; 325 326 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 327 u64 ino, u32 generation) 328 { 329 struct inode *inode; 330 331 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 332 return ERR_PTR(-ESTALE); 333 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 334 return ERR_PTR(-ESTALE); 335 336 /* 337 * ext2_iget isn't quite right if the inode is currently unallocated! 338 * However ext2_iget currently does appropriate checks to handle stale 339 * inodes so everything is OK. 340 */ 341 inode = ext2_iget(sb, ino); 342 if (IS_ERR(inode)) 343 return ERR_CAST(inode); 344 if (generation && inode->i_generation != generation) { 345 /* we didn't find the right inode.. */ 346 iput(inode); 347 return ERR_PTR(-ESTALE); 348 } 349 return inode; 350 } 351 352 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 353 int fh_len, int fh_type) 354 { 355 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 356 ext2_nfs_get_inode); 357 } 358 359 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 360 int fh_len, int fh_type) 361 { 362 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 363 ext2_nfs_get_inode); 364 } 365 366 static const struct export_operations ext2_export_ops = { 367 .fh_to_dentry = ext2_fh_to_dentry, 368 .fh_to_parent = ext2_fh_to_parent, 369 .get_parent = ext2_get_parent, 370 }; 371 372 static unsigned long get_sb_block(void **data) 373 { 374 unsigned long sb_block; 375 char *options = (char *) *data; 376 377 if (!options || strncmp(options, "sb=", 3) != 0) 378 return 1; /* Default location */ 379 options += 3; 380 sb_block = simple_strtoul(options, &options, 0); 381 if (*options && *options != ',') { 382 printk("EXT2-fs: Invalid sb specification: %s\n", 383 (char *) *data); 384 return 1; 385 } 386 if (*options == ',') 387 options++; 388 *data = (void *) options; 389 return sb_block; 390 } 391 392 enum { 393 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 394 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 395 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 396 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 397 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, 398 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 399 }; 400 401 static const match_table_t tokens = { 402 {Opt_bsd_df, "bsddf"}, 403 {Opt_minix_df, "minixdf"}, 404 {Opt_grpid, "grpid"}, 405 {Opt_grpid, "bsdgroups"}, 406 {Opt_nogrpid, "nogrpid"}, 407 {Opt_nogrpid, "sysvgroups"}, 408 {Opt_resgid, "resgid=%u"}, 409 {Opt_resuid, "resuid=%u"}, 410 {Opt_sb, "sb=%u"}, 411 {Opt_err_cont, "errors=continue"}, 412 {Opt_err_panic, "errors=panic"}, 413 {Opt_err_ro, "errors=remount-ro"}, 414 {Opt_nouid32, "nouid32"}, 415 {Opt_nocheck, "check=none"}, 416 {Opt_nocheck, "nocheck"}, 417 {Opt_debug, "debug"}, 418 {Opt_oldalloc, "oldalloc"}, 419 {Opt_orlov, "orlov"}, 420 {Opt_nobh, "nobh"}, 421 {Opt_user_xattr, "user_xattr"}, 422 {Opt_nouser_xattr, "nouser_xattr"}, 423 {Opt_acl, "acl"}, 424 {Opt_noacl, "noacl"}, 425 {Opt_xip, "xip"}, 426 {Opt_grpquota, "grpquota"}, 427 {Opt_ignore, "noquota"}, 428 {Opt_quota, "quota"}, 429 {Opt_usrquota, "usrquota"}, 430 {Opt_reservation, "reservation"}, 431 {Opt_noreservation, "noreservation"}, 432 {Opt_err, NULL} 433 }; 434 435 static int parse_options(char *options, struct super_block *sb) 436 { 437 char *p; 438 struct ext2_sb_info *sbi = EXT2_SB(sb); 439 substring_t args[MAX_OPT_ARGS]; 440 int option; 441 kuid_t uid; 442 kgid_t gid; 443 444 if (!options) 445 return 1; 446 447 while ((p = strsep (&options, ",")) != NULL) { 448 int token; 449 if (!*p) 450 continue; 451 452 token = match_token(p, tokens, args); 453 switch (token) { 454 case Opt_bsd_df: 455 clear_opt (sbi->s_mount_opt, MINIX_DF); 456 break; 457 case Opt_minix_df: 458 set_opt (sbi->s_mount_opt, MINIX_DF); 459 break; 460 case Opt_grpid: 461 set_opt (sbi->s_mount_opt, GRPID); 462 break; 463 case Opt_nogrpid: 464 clear_opt (sbi->s_mount_opt, GRPID); 465 break; 466 case Opt_resuid: 467 if (match_int(&args[0], &option)) 468 return 0; 469 uid = make_kuid(current_user_ns(), option); 470 if (!uid_valid(uid)) { 471 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option); 472 return 0; 473 474 } 475 sbi->s_resuid = uid; 476 break; 477 case Opt_resgid: 478 if (match_int(&args[0], &option)) 479 return 0; 480 gid = make_kgid(current_user_ns(), option); 481 if (!gid_valid(gid)) { 482 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option); 483 return 0; 484 } 485 sbi->s_resgid = gid; 486 break; 487 case Opt_sb: 488 /* handled by get_sb_block() instead of here */ 489 /* *sb_block = match_int(&args[0]); */ 490 break; 491 case Opt_err_panic: 492 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 493 clear_opt (sbi->s_mount_opt, ERRORS_RO); 494 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 495 break; 496 case Opt_err_ro: 497 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 498 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 499 set_opt (sbi->s_mount_opt, ERRORS_RO); 500 break; 501 case Opt_err_cont: 502 clear_opt (sbi->s_mount_opt, ERRORS_RO); 503 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 504 set_opt (sbi->s_mount_opt, ERRORS_CONT); 505 break; 506 case Opt_nouid32: 507 set_opt (sbi->s_mount_opt, NO_UID32); 508 break; 509 case Opt_nocheck: 510 clear_opt (sbi->s_mount_opt, CHECK); 511 break; 512 case Opt_debug: 513 set_opt (sbi->s_mount_opt, DEBUG); 514 break; 515 case Opt_oldalloc: 516 set_opt (sbi->s_mount_opt, OLDALLOC); 517 break; 518 case Opt_orlov: 519 clear_opt (sbi->s_mount_opt, OLDALLOC); 520 break; 521 case Opt_nobh: 522 set_opt (sbi->s_mount_opt, NOBH); 523 break; 524 #ifdef CONFIG_EXT2_FS_XATTR 525 case Opt_user_xattr: 526 set_opt (sbi->s_mount_opt, XATTR_USER); 527 break; 528 case Opt_nouser_xattr: 529 clear_opt (sbi->s_mount_opt, XATTR_USER); 530 break; 531 #else 532 case Opt_user_xattr: 533 case Opt_nouser_xattr: 534 ext2_msg(sb, KERN_INFO, "(no)user_xattr options" 535 "not supported"); 536 break; 537 #endif 538 #ifdef CONFIG_EXT2_FS_POSIX_ACL 539 case Opt_acl: 540 set_opt(sbi->s_mount_opt, POSIX_ACL); 541 break; 542 case Opt_noacl: 543 clear_opt(sbi->s_mount_opt, POSIX_ACL); 544 break; 545 #else 546 case Opt_acl: 547 case Opt_noacl: 548 ext2_msg(sb, KERN_INFO, 549 "(no)acl options not supported"); 550 break; 551 #endif 552 case Opt_xip: 553 #ifdef CONFIG_EXT2_FS_XIP 554 set_opt (sbi->s_mount_opt, XIP); 555 #else 556 ext2_msg(sb, KERN_INFO, "xip option not supported"); 557 #endif 558 break; 559 560 #if defined(CONFIG_QUOTA) 561 case Opt_quota: 562 case Opt_usrquota: 563 set_opt(sbi->s_mount_opt, USRQUOTA); 564 break; 565 566 case Opt_grpquota: 567 set_opt(sbi->s_mount_opt, GRPQUOTA); 568 break; 569 #else 570 case Opt_quota: 571 case Opt_usrquota: 572 case Opt_grpquota: 573 ext2_msg(sb, KERN_INFO, 574 "quota operations not supported"); 575 break; 576 #endif 577 578 case Opt_reservation: 579 set_opt(sbi->s_mount_opt, RESERVATION); 580 ext2_msg(sb, KERN_INFO, "reservations ON"); 581 break; 582 case Opt_noreservation: 583 clear_opt(sbi->s_mount_opt, RESERVATION); 584 ext2_msg(sb, KERN_INFO, "reservations OFF"); 585 break; 586 case Opt_ignore: 587 break; 588 default: 589 return 0; 590 } 591 } 592 return 1; 593 } 594 595 static int ext2_setup_super (struct super_block * sb, 596 struct ext2_super_block * es, 597 int read_only) 598 { 599 int res = 0; 600 struct ext2_sb_info *sbi = EXT2_SB(sb); 601 602 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 603 ext2_msg(sb, KERN_ERR, 604 "error: revision level too high, " 605 "forcing read-only mode"); 606 res = MS_RDONLY; 607 } 608 if (read_only) 609 return res; 610 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 611 ext2_msg(sb, KERN_WARNING, 612 "warning: mounting unchecked fs, " 613 "running e2fsck is recommended"); 614 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 615 ext2_msg(sb, KERN_WARNING, 616 "warning: mounting fs with errors, " 617 "running e2fsck is recommended"); 618 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 619 le16_to_cpu(es->s_mnt_count) >= 620 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 621 ext2_msg(sb, KERN_WARNING, 622 "warning: maximal mount count reached, " 623 "running e2fsck is recommended"); 624 else if (le32_to_cpu(es->s_checkinterval) && 625 (le32_to_cpu(es->s_lastcheck) + 626 le32_to_cpu(es->s_checkinterval) <= get_seconds())) 627 ext2_msg(sb, KERN_WARNING, 628 "warning: checktime reached, " 629 "running e2fsck is recommended"); 630 if (!le16_to_cpu(es->s_max_mnt_count)) 631 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 632 le16_add_cpu(&es->s_mnt_count, 1); 633 if (test_opt (sb, DEBUG)) 634 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, " 635 "bpg=%lu, ipg=%lu, mo=%04lx]", 636 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 637 sbi->s_frag_size, 638 sbi->s_groups_count, 639 EXT2_BLOCKS_PER_GROUP(sb), 640 EXT2_INODES_PER_GROUP(sb), 641 sbi->s_mount_opt); 642 return res; 643 } 644 645 static int ext2_check_descriptors(struct super_block *sb) 646 { 647 int i; 648 struct ext2_sb_info *sbi = EXT2_SB(sb); 649 650 ext2_debug ("Checking group descriptors"); 651 652 for (i = 0; i < sbi->s_groups_count; i++) { 653 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 654 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 655 ext2_fsblk_t last_block; 656 657 if (i == sbi->s_groups_count - 1) 658 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 659 else 660 last_block = first_block + 661 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 662 663 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 664 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 665 { 666 ext2_error (sb, "ext2_check_descriptors", 667 "Block bitmap for group %d" 668 " not in group (block %lu)!", 669 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 670 return 0; 671 } 672 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 673 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 674 { 675 ext2_error (sb, "ext2_check_descriptors", 676 "Inode bitmap for group %d" 677 " not in group (block %lu)!", 678 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 679 return 0; 680 } 681 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 682 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 683 last_block) 684 { 685 ext2_error (sb, "ext2_check_descriptors", 686 "Inode table for group %d" 687 " not in group (block %lu)!", 688 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 689 return 0; 690 } 691 } 692 return 1; 693 } 694 695 /* 696 * Maximal file size. There is a direct, and {,double-,triple-}indirect 697 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 698 * We need to be 1 filesystem block less than the 2^32 sector limit. 699 */ 700 static loff_t ext2_max_size(int bits) 701 { 702 loff_t res = EXT2_NDIR_BLOCKS; 703 int meta_blocks; 704 loff_t upper_limit; 705 706 /* This is calculated to be the largest file size for a 707 * dense, file such that the total number of 708 * sectors in the file, including data and all indirect blocks, 709 * does not exceed 2^32 -1 710 * __u32 i_blocks representing the total number of 711 * 512 bytes blocks of the file 712 */ 713 upper_limit = (1LL << 32) - 1; 714 715 /* total blocks in file system block size */ 716 upper_limit >>= (bits - 9); 717 718 719 /* indirect blocks */ 720 meta_blocks = 1; 721 /* double indirect blocks */ 722 meta_blocks += 1 + (1LL << (bits-2)); 723 /* tripple indirect blocks */ 724 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2))); 725 726 upper_limit -= meta_blocks; 727 upper_limit <<= bits; 728 729 res += 1LL << (bits-2); 730 res += 1LL << (2*(bits-2)); 731 res += 1LL << (3*(bits-2)); 732 res <<= bits; 733 if (res > upper_limit) 734 res = upper_limit; 735 736 if (res > MAX_LFS_FILESIZE) 737 res = MAX_LFS_FILESIZE; 738 739 return res; 740 } 741 742 static unsigned long descriptor_loc(struct super_block *sb, 743 unsigned long logic_sb_block, 744 int nr) 745 { 746 struct ext2_sb_info *sbi = EXT2_SB(sb); 747 unsigned long bg, first_meta_bg; 748 int has_super = 0; 749 750 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 751 752 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 753 nr < first_meta_bg) 754 return (logic_sb_block + nr + 1); 755 bg = sbi->s_desc_per_block * nr; 756 if (ext2_bg_has_super(sb, bg)) 757 has_super = 1; 758 759 return ext2_group_first_block_no(sb, bg) + has_super; 760 } 761 762 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 763 { 764 struct buffer_head * bh; 765 struct ext2_sb_info * sbi; 766 struct ext2_super_block * es; 767 struct inode *root; 768 unsigned long block; 769 unsigned long sb_block = get_sb_block(&data); 770 unsigned long logic_sb_block; 771 unsigned long offset = 0; 772 unsigned long def_mount_opts; 773 long ret = -EINVAL; 774 int blocksize = BLOCK_SIZE; 775 int db_count; 776 int i, j; 777 __le32 features; 778 int err; 779 780 err = -ENOMEM; 781 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 782 if (!sbi) 783 goto failed; 784 785 sbi->s_blockgroup_lock = 786 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 787 if (!sbi->s_blockgroup_lock) { 788 kfree(sbi); 789 goto failed; 790 } 791 sb->s_fs_info = sbi; 792 sbi->s_sb_block = sb_block; 793 794 spin_lock_init(&sbi->s_lock); 795 796 /* 797 * See what the current blocksize for the device is, and 798 * use that as the blocksize. Otherwise (or if the blocksize 799 * is smaller than the default) use the default. 800 * This is important for devices that have a hardware 801 * sectorsize that is larger than the default. 802 */ 803 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 804 if (!blocksize) { 805 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 806 goto failed_sbi; 807 } 808 809 /* 810 * If the superblock doesn't start on a hardware sector boundary, 811 * calculate the offset. 812 */ 813 if (blocksize != BLOCK_SIZE) { 814 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 815 offset = (sb_block*BLOCK_SIZE) % blocksize; 816 } else { 817 logic_sb_block = sb_block; 818 } 819 820 if (!(bh = sb_bread(sb, logic_sb_block))) { 821 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 822 goto failed_sbi; 823 } 824 /* 825 * Note: s_es must be initialized as soon as possible because 826 * some ext2 macro-instructions depend on its value 827 */ 828 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 829 sbi->s_es = es; 830 sb->s_magic = le16_to_cpu(es->s_magic); 831 832 if (sb->s_magic != EXT2_SUPER_MAGIC) 833 goto cantfind_ext2; 834 835 /* Set defaults before we parse the mount options */ 836 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 837 if (def_mount_opts & EXT2_DEFM_DEBUG) 838 set_opt(sbi->s_mount_opt, DEBUG); 839 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 840 set_opt(sbi->s_mount_opt, GRPID); 841 if (def_mount_opts & EXT2_DEFM_UID16) 842 set_opt(sbi->s_mount_opt, NO_UID32); 843 #ifdef CONFIG_EXT2_FS_XATTR 844 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 845 set_opt(sbi->s_mount_opt, XATTR_USER); 846 #endif 847 #ifdef CONFIG_EXT2_FS_POSIX_ACL 848 if (def_mount_opts & EXT2_DEFM_ACL) 849 set_opt(sbi->s_mount_opt, POSIX_ACL); 850 #endif 851 852 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 853 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 854 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 855 set_opt(sbi->s_mount_opt, ERRORS_CONT); 856 else 857 set_opt(sbi->s_mount_opt, ERRORS_RO); 858 859 sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid)); 860 sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid)); 861 862 set_opt(sbi->s_mount_opt, RESERVATION); 863 864 if (!parse_options((char *) data, sb)) 865 goto failed_mount; 866 867 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 868 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 869 MS_POSIXACL : 0); 870 871 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 872 EXT2_MOUNT_XIP if not */ 873 874 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 875 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 876 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 877 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 878 ext2_msg(sb, KERN_WARNING, 879 "warning: feature flags set on rev 0 fs, " 880 "running e2fsck is recommended"); 881 /* 882 * Check feature flags regardless of the revision level, since we 883 * previously didn't change the revision level when setting the flags, 884 * so there is a chance incompat flags are set on a rev 0 filesystem. 885 */ 886 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 887 if (features) { 888 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 889 "unsupported optional features (%x)", 890 le32_to_cpu(features)); 891 goto failed_mount; 892 } 893 if (!(sb->s_flags & MS_RDONLY) && 894 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 895 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 896 "unsupported optional features (%x)", 897 le32_to_cpu(features)); 898 goto failed_mount; 899 } 900 901 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 902 903 if (ext2_use_xip(sb) && blocksize != PAGE_SIZE) { 904 if (!silent) 905 ext2_msg(sb, KERN_ERR, 906 "error: unsupported blocksize for xip"); 907 goto failed_mount; 908 } 909 910 /* If the blocksize doesn't match, re-read the thing.. */ 911 if (sb->s_blocksize != blocksize) { 912 brelse(bh); 913 914 if (!sb_set_blocksize(sb, blocksize)) { 915 ext2_msg(sb, KERN_ERR, 916 "error: bad blocksize %d", blocksize); 917 goto failed_sbi; 918 } 919 920 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 921 offset = (sb_block*BLOCK_SIZE) % blocksize; 922 bh = sb_bread(sb, logic_sb_block); 923 if(!bh) { 924 ext2_msg(sb, KERN_ERR, "error: couldn't read" 925 "superblock on 2nd try"); 926 goto failed_sbi; 927 } 928 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 929 sbi->s_es = es; 930 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 931 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 932 goto failed_mount; 933 } 934 } 935 936 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 937 sb->s_max_links = EXT2_LINK_MAX; 938 939 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 940 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 941 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 942 } else { 943 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 944 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 945 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 946 !is_power_of_2(sbi->s_inode_size) || 947 (sbi->s_inode_size > blocksize)) { 948 ext2_msg(sb, KERN_ERR, 949 "error: unsupported inode size: %d", 950 sbi->s_inode_size); 951 goto failed_mount; 952 } 953 } 954 955 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 956 le32_to_cpu(es->s_log_frag_size); 957 if (sbi->s_frag_size == 0) 958 goto cantfind_ext2; 959 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 960 961 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 962 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 963 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 964 965 if (EXT2_INODE_SIZE(sb) == 0) 966 goto cantfind_ext2; 967 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 968 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 969 goto cantfind_ext2; 970 sbi->s_itb_per_group = sbi->s_inodes_per_group / 971 sbi->s_inodes_per_block; 972 sbi->s_desc_per_block = sb->s_blocksize / 973 sizeof (struct ext2_group_desc); 974 sbi->s_sbh = bh; 975 sbi->s_mount_state = le16_to_cpu(es->s_state); 976 sbi->s_addr_per_block_bits = 977 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 978 sbi->s_desc_per_block_bits = 979 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 980 981 if (sb->s_magic != EXT2_SUPER_MAGIC) 982 goto cantfind_ext2; 983 984 if (sb->s_blocksize != bh->b_size) { 985 if (!silent) 986 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 987 goto failed_mount; 988 } 989 990 if (sb->s_blocksize != sbi->s_frag_size) { 991 ext2_msg(sb, KERN_ERR, 992 "error: fragsize %lu != blocksize %lu" 993 "(not supported yet)", 994 sbi->s_frag_size, sb->s_blocksize); 995 goto failed_mount; 996 } 997 998 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 999 ext2_msg(sb, KERN_ERR, 1000 "error: #blocks per group too big: %lu", 1001 sbi->s_blocks_per_group); 1002 goto failed_mount; 1003 } 1004 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 1005 ext2_msg(sb, KERN_ERR, 1006 "error: #fragments per group too big: %lu", 1007 sbi->s_frags_per_group); 1008 goto failed_mount; 1009 } 1010 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 1011 ext2_msg(sb, KERN_ERR, 1012 "error: #inodes per group too big: %lu", 1013 sbi->s_inodes_per_group); 1014 goto failed_mount; 1015 } 1016 1017 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 1018 goto cantfind_ext2; 1019 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 1020 le32_to_cpu(es->s_first_data_block) - 1) 1021 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 1022 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 1023 EXT2_DESC_PER_BLOCK(sb); 1024 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 1025 if (sbi->s_group_desc == NULL) { 1026 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1027 goto failed_mount; 1028 } 1029 bgl_lock_init(sbi->s_blockgroup_lock); 1030 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1031 if (!sbi->s_debts) { 1032 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1033 goto failed_mount_group_desc; 1034 } 1035 for (i = 0; i < db_count; i++) { 1036 block = descriptor_loc(sb, logic_sb_block, i); 1037 sbi->s_group_desc[i] = sb_bread(sb, block); 1038 if (!sbi->s_group_desc[i]) { 1039 for (j = 0; j < i; j++) 1040 brelse (sbi->s_group_desc[j]); 1041 ext2_msg(sb, KERN_ERR, 1042 "error: unable to read group descriptors"); 1043 goto failed_mount_group_desc; 1044 } 1045 } 1046 if (!ext2_check_descriptors (sb)) { 1047 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1048 goto failed_mount2; 1049 } 1050 sbi->s_gdb_count = db_count; 1051 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1052 spin_lock_init(&sbi->s_next_gen_lock); 1053 1054 /* per fileystem reservation list head & lock */ 1055 spin_lock_init(&sbi->s_rsv_window_lock); 1056 sbi->s_rsv_window_root = RB_ROOT; 1057 /* 1058 * Add a single, static dummy reservation to the start of the 1059 * reservation window list --- it gives us a placeholder for 1060 * append-at-start-of-list which makes the allocation logic 1061 * _much_ simpler. 1062 */ 1063 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1064 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1065 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1066 sbi->s_rsv_window_head.rsv_goal_size = 0; 1067 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1068 1069 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1070 ext2_count_free_blocks(sb)); 1071 if (!err) { 1072 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1073 ext2_count_free_inodes(sb)); 1074 } 1075 if (!err) { 1076 err = percpu_counter_init(&sbi->s_dirs_counter, 1077 ext2_count_dirs(sb)); 1078 } 1079 if (err) { 1080 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1081 goto failed_mount3; 1082 } 1083 /* 1084 * set up enough so that it can read an inode 1085 */ 1086 sb->s_op = &ext2_sops; 1087 sb->s_export_op = &ext2_export_ops; 1088 sb->s_xattr = ext2_xattr_handlers; 1089 1090 #ifdef CONFIG_QUOTA 1091 sb->dq_op = &dquot_operations; 1092 sb->s_qcop = &dquot_quotactl_ops; 1093 #endif 1094 1095 root = ext2_iget(sb, EXT2_ROOT_INO); 1096 if (IS_ERR(root)) { 1097 ret = PTR_ERR(root); 1098 goto failed_mount3; 1099 } 1100 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1101 iput(root); 1102 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1103 goto failed_mount3; 1104 } 1105 1106 sb->s_root = d_make_root(root); 1107 if (!sb->s_root) { 1108 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1109 ret = -ENOMEM; 1110 goto failed_mount3; 1111 } 1112 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1113 ext2_msg(sb, KERN_WARNING, 1114 "warning: mounting ext3 filesystem as ext2"); 1115 if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY)) 1116 sb->s_flags |= MS_RDONLY; 1117 ext2_write_super(sb); 1118 return 0; 1119 1120 cantfind_ext2: 1121 if (!silent) 1122 ext2_msg(sb, KERN_ERR, 1123 "error: can't find an ext2 filesystem on dev %s.", 1124 sb->s_id); 1125 goto failed_mount; 1126 failed_mount3: 1127 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1128 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1129 percpu_counter_destroy(&sbi->s_dirs_counter); 1130 failed_mount2: 1131 for (i = 0; i < db_count; i++) 1132 brelse(sbi->s_group_desc[i]); 1133 failed_mount_group_desc: 1134 kfree(sbi->s_group_desc); 1135 kfree(sbi->s_debts); 1136 failed_mount: 1137 brelse(bh); 1138 failed_sbi: 1139 sb->s_fs_info = NULL; 1140 kfree(sbi->s_blockgroup_lock); 1141 kfree(sbi); 1142 failed: 1143 return ret; 1144 } 1145 1146 static void ext2_clear_super_error(struct super_block *sb) 1147 { 1148 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1149 1150 if (buffer_write_io_error(sbh)) { 1151 /* 1152 * Oh, dear. A previous attempt to write the 1153 * superblock failed. This could happen because the 1154 * USB device was yanked out. Or it could happen to 1155 * be a transient write error and maybe the block will 1156 * be remapped. Nothing we can do but to retry the 1157 * write and hope for the best. 1158 */ 1159 ext2_msg(sb, KERN_ERR, 1160 "previous I/O error to superblock detected\n"); 1161 clear_buffer_write_io_error(sbh); 1162 set_buffer_uptodate(sbh); 1163 } 1164 } 1165 1166 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, 1167 int wait) 1168 { 1169 ext2_clear_super_error(sb); 1170 spin_lock(&EXT2_SB(sb)->s_lock); 1171 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1172 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1173 es->s_wtime = cpu_to_le32(get_seconds()); 1174 /* unlock before we do IO */ 1175 spin_unlock(&EXT2_SB(sb)->s_lock); 1176 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1177 if (wait) 1178 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1179 } 1180 1181 /* 1182 * In the second extended file system, it is not necessary to 1183 * write the super block since we use a mapping of the 1184 * disk super block in a buffer. 1185 * 1186 * However, this function is still used to set the fs valid 1187 * flags to 0. We need to set this flag to 0 since the fs 1188 * may have been checked while mounted and e2fsck may have 1189 * set s_state to EXT2_VALID_FS after some corrections. 1190 */ 1191 static int ext2_sync_fs(struct super_block *sb, int wait) 1192 { 1193 struct ext2_sb_info *sbi = EXT2_SB(sb); 1194 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1195 1196 /* 1197 * Write quota structures to quota file, sync_blockdev() will write 1198 * them to disk later 1199 */ 1200 dquot_writeback_dquots(sb, -1); 1201 1202 spin_lock(&sbi->s_lock); 1203 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1204 ext2_debug("setting valid to 0\n"); 1205 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1206 } 1207 spin_unlock(&sbi->s_lock); 1208 ext2_sync_super(sb, es, wait); 1209 return 0; 1210 } 1211 1212 static int ext2_freeze(struct super_block *sb) 1213 { 1214 struct ext2_sb_info *sbi = EXT2_SB(sb); 1215 1216 /* 1217 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared 1218 * because we have unattached inodes and thus filesystem is not fully 1219 * consistent. 1220 */ 1221 if (atomic_long_read(&sb->s_remove_count)) { 1222 ext2_sync_fs(sb, 1); 1223 return 0; 1224 } 1225 /* Set EXT2_FS_VALID flag */ 1226 spin_lock(&sbi->s_lock); 1227 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); 1228 spin_unlock(&sbi->s_lock); 1229 ext2_sync_super(sb, sbi->s_es, 1); 1230 1231 return 0; 1232 } 1233 1234 static int ext2_unfreeze(struct super_block *sb) 1235 { 1236 /* Just write sb to clear EXT2_VALID_FS flag */ 1237 ext2_write_super(sb); 1238 1239 return 0; 1240 } 1241 1242 void ext2_write_super(struct super_block *sb) 1243 { 1244 if (!(sb->s_flags & MS_RDONLY)) 1245 ext2_sync_fs(sb, 1); 1246 } 1247 1248 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1249 { 1250 struct ext2_sb_info * sbi = EXT2_SB(sb); 1251 struct ext2_super_block * es; 1252 unsigned long old_mount_opt = sbi->s_mount_opt; 1253 struct ext2_mount_options old_opts; 1254 unsigned long old_sb_flags; 1255 int err; 1256 1257 spin_lock(&sbi->s_lock); 1258 1259 /* Store the old options */ 1260 old_sb_flags = sb->s_flags; 1261 old_opts.s_mount_opt = sbi->s_mount_opt; 1262 old_opts.s_resuid = sbi->s_resuid; 1263 old_opts.s_resgid = sbi->s_resgid; 1264 1265 /* 1266 * Allow the "check" option to be passed as a remount option. 1267 */ 1268 if (!parse_options(data, sb)) { 1269 err = -EINVAL; 1270 goto restore_opts; 1271 } 1272 1273 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1274 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1275 1276 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 1277 EXT2_MOUNT_XIP if not */ 1278 1279 if ((ext2_use_xip(sb)) && (sb->s_blocksize != PAGE_SIZE)) { 1280 ext2_msg(sb, KERN_WARNING, 1281 "warning: unsupported blocksize for xip"); 1282 err = -EINVAL; 1283 goto restore_opts; 1284 } 1285 1286 es = sbi->s_es; 1287 if ((sbi->s_mount_opt ^ old_mount_opt) & EXT2_MOUNT_XIP) { 1288 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1289 "xip flag with busy inodes while remounting"); 1290 sbi->s_mount_opt &= ~EXT2_MOUNT_XIP; 1291 sbi->s_mount_opt |= old_mount_opt & EXT2_MOUNT_XIP; 1292 } 1293 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { 1294 spin_unlock(&sbi->s_lock); 1295 return 0; 1296 } 1297 if (*flags & MS_RDONLY) { 1298 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1299 !(sbi->s_mount_state & EXT2_VALID_FS)) { 1300 spin_unlock(&sbi->s_lock); 1301 return 0; 1302 } 1303 1304 /* 1305 * OK, we are remounting a valid rw partition rdonly, so set 1306 * the rdonly flag and then mark the partition as valid again. 1307 */ 1308 es->s_state = cpu_to_le16(sbi->s_mount_state); 1309 es->s_mtime = cpu_to_le32(get_seconds()); 1310 spin_unlock(&sbi->s_lock); 1311 1312 err = dquot_suspend(sb, -1); 1313 if (err < 0) { 1314 spin_lock(&sbi->s_lock); 1315 goto restore_opts; 1316 } 1317 1318 ext2_sync_super(sb, es, 1); 1319 } else { 1320 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1321 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1322 if (ret) { 1323 ext2_msg(sb, KERN_WARNING, 1324 "warning: couldn't remount RDWR because of " 1325 "unsupported optional features (%x).", 1326 le32_to_cpu(ret)); 1327 err = -EROFS; 1328 goto restore_opts; 1329 } 1330 /* 1331 * Mounting a RDONLY partition read-write, so reread and 1332 * store the current valid flag. (It may have been changed 1333 * by e2fsck since we originally mounted the partition.) 1334 */ 1335 sbi->s_mount_state = le16_to_cpu(es->s_state); 1336 if (!ext2_setup_super (sb, es, 0)) 1337 sb->s_flags &= ~MS_RDONLY; 1338 spin_unlock(&sbi->s_lock); 1339 1340 ext2_write_super(sb); 1341 1342 dquot_resume(sb, -1); 1343 } 1344 1345 return 0; 1346 restore_opts: 1347 sbi->s_mount_opt = old_opts.s_mount_opt; 1348 sbi->s_resuid = old_opts.s_resuid; 1349 sbi->s_resgid = old_opts.s_resgid; 1350 sb->s_flags = old_sb_flags; 1351 spin_unlock(&sbi->s_lock); 1352 return err; 1353 } 1354 1355 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1356 { 1357 struct super_block *sb = dentry->d_sb; 1358 struct ext2_sb_info *sbi = EXT2_SB(sb); 1359 struct ext2_super_block *es = sbi->s_es; 1360 u64 fsid; 1361 1362 spin_lock(&sbi->s_lock); 1363 1364 if (test_opt (sb, MINIX_DF)) 1365 sbi->s_overhead_last = 0; 1366 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1367 unsigned long i, overhead = 0; 1368 smp_rmb(); 1369 1370 /* 1371 * Compute the overhead (FS structures). This is constant 1372 * for a given filesystem unless the number of block groups 1373 * changes so we cache the previous value until it does. 1374 */ 1375 1376 /* 1377 * All of the blocks before first_data_block are 1378 * overhead 1379 */ 1380 overhead = le32_to_cpu(es->s_first_data_block); 1381 1382 /* 1383 * Add the overhead attributed to the superblock and 1384 * block group descriptors. If the sparse superblocks 1385 * feature is turned on, then not all groups have this. 1386 */ 1387 for (i = 0; i < sbi->s_groups_count; i++) 1388 overhead += ext2_bg_has_super(sb, i) + 1389 ext2_bg_num_gdb(sb, i); 1390 1391 /* 1392 * Every block group has an inode bitmap, a block 1393 * bitmap, and an inode table. 1394 */ 1395 overhead += (sbi->s_groups_count * 1396 (2 + sbi->s_itb_per_group)); 1397 sbi->s_overhead_last = overhead; 1398 smp_wmb(); 1399 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1400 } 1401 1402 buf->f_type = EXT2_SUPER_MAGIC; 1403 buf->f_bsize = sb->s_blocksize; 1404 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1405 buf->f_bfree = ext2_count_free_blocks(sb); 1406 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1407 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1408 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1409 buf->f_bavail = 0; 1410 buf->f_files = le32_to_cpu(es->s_inodes_count); 1411 buf->f_ffree = ext2_count_free_inodes(sb); 1412 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1413 buf->f_namelen = EXT2_NAME_LEN; 1414 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1415 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1416 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1417 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1418 spin_unlock(&sbi->s_lock); 1419 return 0; 1420 } 1421 1422 static struct dentry *ext2_mount(struct file_system_type *fs_type, 1423 int flags, const char *dev_name, void *data) 1424 { 1425 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1426 } 1427 1428 #ifdef CONFIG_QUOTA 1429 1430 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1431 * acquiring the locks... As quota files are never truncated and quota code 1432 * itself serializes the operations (and no one else should touch the files) 1433 * we don't have to be afraid of races */ 1434 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1435 size_t len, loff_t off) 1436 { 1437 struct inode *inode = sb_dqopt(sb)->files[type]; 1438 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1439 int err = 0; 1440 int offset = off & (sb->s_blocksize - 1); 1441 int tocopy; 1442 size_t toread; 1443 struct buffer_head tmp_bh; 1444 struct buffer_head *bh; 1445 loff_t i_size = i_size_read(inode); 1446 1447 if (off > i_size) 1448 return 0; 1449 if (off+len > i_size) 1450 len = i_size-off; 1451 toread = len; 1452 while (toread > 0) { 1453 tocopy = sb->s_blocksize - offset < toread ? 1454 sb->s_blocksize - offset : toread; 1455 1456 tmp_bh.b_state = 0; 1457 tmp_bh.b_size = sb->s_blocksize; 1458 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1459 if (err < 0) 1460 return err; 1461 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1462 memset(data, 0, tocopy); 1463 else { 1464 bh = sb_bread(sb, tmp_bh.b_blocknr); 1465 if (!bh) 1466 return -EIO; 1467 memcpy(data, bh->b_data+offset, tocopy); 1468 brelse(bh); 1469 } 1470 offset = 0; 1471 toread -= tocopy; 1472 data += tocopy; 1473 blk++; 1474 } 1475 return len; 1476 } 1477 1478 /* Write to quotafile */ 1479 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1480 const char *data, size_t len, loff_t off) 1481 { 1482 struct inode *inode = sb_dqopt(sb)->files[type]; 1483 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1484 int err = 0; 1485 int offset = off & (sb->s_blocksize - 1); 1486 int tocopy; 1487 size_t towrite = len; 1488 struct buffer_head tmp_bh; 1489 struct buffer_head *bh; 1490 1491 while (towrite > 0) { 1492 tocopy = sb->s_blocksize - offset < towrite ? 1493 sb->s_blocksize - offset : towrite; 1494 1495 tmp_bh.b_state = 0; 1496 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1497 if (err < 0) 1498 goto out; 1499 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1500 bh = sb_bread(sb, tmp_bh.b_blocknr); 1501 else 1502 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1503 if (!bh) { 1504 err = -EIO; 1505 goto out; 1506 } 1507 lock_buffer(bh); 1508 memcpy(bh->b_data+offset, data, tocopy); 1509 flush_dcache_page(bh->b_page); 1510 set_buffer_uptodate(bh); 1511 mark_buffer_dirty(bh); 1512 unlock_buffer(bh); 1513 brelse(bh); 1514 offset = 0; 1515 towrite -= tocopy; 1516 data += tocopy; 1517 blk++; 1518 } 1519 out: 1520 if (len == towrite) 1521 return err; 1522 if (inode->i_size < off+len-towrite) 1523 i_size_write(inode, off+len-towrite); 1524 inode->i_version++; 1525 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1526 mark_inode_dirty(inode); 1527 return len - towrite; 1528 } 1529 1530 #endif 1531 1532 static struct file_system_type ext2_fs_type = { 1533 .owner = THIS_MODULE, 1534 .name = "ext2", 1535 .mount = ext2_mount, 1536 .kill_sb = kill_block_super, 1537 .fs_flags = FS_REQUIRES_DEV, 1538 }; 1539 1540 static int __init init_ext2_fs(void) 1541 { 1542 int err = init_ext2_xattr(); 1543 if (err) 1544 return err; 1545 err = init_inodecache(); 1546 if (err) 1547 goto out1; 1548 err = register_filesystem(&ext2_fs_type); 1549 if (err) 1550 goto out; 1551 return 0; 1552 out: 1553 destroy_inodecache(); 1554 out1: 1555 exit_ext2_xattr(); 1556 return err; 1557 } 1558 1559 static void __exit exit_ext2_fs(void) 1560 { 1561 unregister_filesystem(&ext2_fs_type); 1562 destroy_inodecache(); 1563 exit_ext2_xattr(); 1564 } 1565 1566 MODULE_AUTHOR("Remy Card and others"); 1567 MODULE_DESCRIPTION("Second Extended Filesystem"); 1568 MODULE_LICENSE("GPL"); 1569 module_init(init_ext2_fs) 1570 module_exit(exit_ext2_fs) 1571