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