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/config.h> 20 #include <linux/module.h> 21 #include <linux/string.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/smp_lock.h> 29 #include <linux/vfs.h> 30 #include <asm/uaccess.h> 31 #include "ext2.h" 32 #include "xattr.h" 33 #include "acl.h" 34 35 static void ext2_sync_super(struct super_block *sb, 36 struct ext2_super_block *es); 37 static int ext2_remount (struct super_block * sb, int * flags, char * data); 38 static int ext2_statfs (struct super_block * sb, struct kstatfs * buf); 39 40 void ext2_error (struct super_block * sb, const char * function, 41 const char * fmt, ...) 42 { 43 va_list args; 44 struct ext2_sb_info *sbi = EXT2_SB(sb); 45 struct ext2_super_block *es = sbi->s_es; 46 47 if (!(sb->s_flags & MS_RDONLY)) { 48 sbi->s_mount_state |= EXT2_ERROR_FS; 49 es->s_state = 50 cpu_to_le16(le16_to_cpu(es->s_state) | EXT2_ERROR_FS); 51 ext2_sync_super(sb, es); 52 } 53 54 va_start(args, fmt); 55 printk(KERN_CRIT "EXT2-fs error (device %s): %s: ",sb->s_id, function); 56 vprintk(fmt, args); 57 printk("\n"); 58 va_end(args); 59 60 if (test_opt(sb, ERRORS_PANIC)) 61 panic("EXT2-fs panic from previous error\n"); 62 if (test_opt(sb, ERRORS_RO)) { 63 printk("Remounting filesystem read-only\n"); 64 sb->s_flags |= MS_RDONLY; 65 } 66 } 67 68 void ext2_warning (struct super_block * sb, const char * function, 69 const char * fmt, ...) 70 { 71 va_list args; 72 73 va_start(args, fmt); 74 printk(KERN_WARNING "EXT2-fs warning (device %s): %s: ", 75 sb->s_id, function); 76 vprintk(fmt, args); 77 printk("\n"); 78 va_end(args); 79 } 80 81 void ext2_update_dynamic_rev(struct super_block *sb) 82 { 83 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 84 85 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) 86 return; 87 88 ext2_warning(sb, __FUNCTION__, 89 "updating to rev %d because of new feature flag, " 90 "running e2fsck is recommended", 91 EXT2_DYNAMIC_REV); 92 93 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); 94 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); 95 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); 96 /* leave es->s_feature_*compat flags alone */ 97 /* es->s_uuid will be set by e2fsck if empty */ 98 99 /* 100 * The rest of the superblock fields should be zero, and if not it 101 * means they are likely already in use, so leave them alone. We 102 * can leave it up to e2fsck to clean up any inconsistencies there. 103 */ 104 } 105 106 static void ext2_put_super (struct super_block * sb) 107 { 108 int db_count; 109 int i; 110 struct ext2_sb_info *sbi = EXT2_SB(sb); 111 112 ext2_xattr_put_super(sb); 113 if (!(sb->s_flags & MS_RDONLY)) { 114 struct ext2_super_block *es = sbi->s_es; 115 116 es->s_state = cpu_to_le16(sbi->s_mount_state); 117 ext2_sync_super(sb, es); 118 } 119 db_count = sbi->s_gdb_count; 120 for (i = 0; i < db_count; i++) 121 if (sbi->s_group_desc[i]) 122 brelse (sbi->s_group_desc[i]); 123 kfree(sbi->s_group_desc); 124 kfree(sbi->s_debts); 125 percpu_counter_destroy(&sbi->s_freeblocks_counter); 126 percpu_counter_destroy(&sbi->s_freeinodes_counter); 127 percpu_counter_destroy(&sbi->s_dirs_counter); 128 brelse (sbi->s_sbh); 129 sb->s_fs_info = NULL; 130 kfree(sbi); 131 132 return; 133 } 134 135 static kmem_cache_t * ext2_inode_cachep; 136 137 static struct inode *ext2_alloc_inode(struct super_block *sb) 138 { 139 struct ext2_inode_info *ei; 140 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, SLAB_KERNEL); 141 if (!ei) 142 return NULL; 143 #ifdef CONFIG_EXT2_FS_POSIX_ACL 144 ei->i_acl = EXT2_ACL_NOT_CACHED; 145 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 146 #endif 147 ei->vfs_inode.i_version = 1; 148 return &ei->vfs_inode; 149 } 150 151 static void ext2_destroy_inode(struct inode *inode) 152 { 153 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 154 } 155 156 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags) 157 { 158 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 159 160 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == 161 SLAB_CTOR_CONSTRUCTOR) { 162 rwlock_init(&ei->i_meta_lock); 163 #ifdef CONFIG_EXT2_FS_XATTR 164 init_rwsem(&ei->xattr_sem); 165 #endif 166 inode_init_once(&ei->vfs_inode); 167 } 168 } 169 170 static int init_inodecache(void) 171 { 172 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 173 sizeof(struct ext2_inode_info), 174 0, SLAB_RECLAIM_ACCOUNT, 175 init_once, NULL); 176 if (ext2_inode_cachep == NULL) 177 return -ENOMEM; 178 return 0; 179 } 180 181 static void destroy_inodecache(void) 182 { 183 if (kmem_cache_destroy(ext2_inode_cachep)) 184 printk(KERN_INFO "ext2_inode_cache: not all structures were freed\n"); 185 } 186 187 static void ext2_clear_inode(struct inode *inode) 188 { 189 #ifdef CONFIG_EXT2_FS_POSIX_ACL 190 struct ext2_inode_info *ei = EXT2_I(inode); 191 192 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) { 193 posix_acl_release(ei->i_acl); 194 ei->i_acl = EXT2_ACL_NOT_CACHED; 195 } 196 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) { 197 posix_acl_release(ei->i_default_acl); 198 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 199 } 200 #endif 201 } 202 203 #ifdef CONFIG_QUOTA 204 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 205 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 206 #endif 207 208 static struct super_operations ext2_sops = { 209 .alloc_inode = ext2_alloc_inode, 210 .destroy_inode = ext2_destroy_inode, 211 .read_inode = ext2_read_inode, 212 .write_inode = ext2_write_inode, 213 .put_inode = ext2_put_inode, 214 .delete_inode = ext2_delete_inode, 215 .put_super = ext2_put_super, 216 .write_super = ext2_write_super, 217 .statfs = ext2_statfs, 218 .remount_fs = ext2_remount, 219 .clear_inode = ext2_clear_inode, 220 #ifdef CONFIG_QUOTA 221 .quota_read = ext2_quota_read, 222 .quota_write = ext2_quota_write, 223 #endif 224 }; 225 226 /* Yes, most of these are left as NULL!! 227 * A NULL value implies the default, which works with ext2-like file 228 * systems, but can be improved upon. 229 * Currently only get_parent is required. 230 */ 231 struct dentry *ext2_get_parent(struct dentry *child); 232 static struct export_operations ext2_export_ops = { 233 .get_parent = ext2_get_parent, 234 }; 235 236 static unsigned long get_sb_block(void **data) 237 { 238 unsigned long sb_block; 239 char *options = (char *) *data; 240 241 if (!options || strncmp(options, "sb=", 3) != 0) 242 return 1; /* Default location */ 243 options += 3; 244 sb_block = simple_strtoul(options, &options, 0); 245 if (*options && *options != ',') { 246 printk("EXT2-fs: Invalid sb specification: %s\n", 247 (char *) *data); 248 return 1; 249 } 250 if (*options == ',') 251 options++; 252 *data = (void *) options; 253 return sb_block; 254 } 255 256 enum { 257 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 258 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro, 259 Opt_nouid32, Opt_check, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov, Opt_nobh, 260 Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl, 261 Opt_ignore, Opt_err, 262 }; 263 264 static match_table_t tokens = { 265 {Opt_bsd_df, "bsddf"}, 266 {Opt_minix_df, "minixdf"}, 267 {Opt_grpid, "grpid"}, 268 {Opt_grpid, "bsdgroups"}, 269 {Opt_nogrpid, "nogrpid"}, 270 {Opt_nogrpid, "sysvgroups"}, 271 {Opt_resgid, "resgid=%u"}, 272 {Opt_resuid, "resuid=%u"}, 273 {Opt_sb, "sb=%u"}, 274 {Opt_err_cont, "errors=continue"}, 275 {Opt_err_panic, "errors=panic"}, 276 {Opt_err_ro, "errors=remount-ro"}, 277 {Opt_nouid32, "nouid32"}, 278 {Opt_nocheck, "check=none"}, 279 {Opt_nocheck, "nocheck"}, 280 {Opt_check, "check"}, 281 {Opt_debug, "debug"}, 282 {Opt_oldalloc, "oldalloc"}, 283 {Opt_orlov, "orlov"}, 284 {Opt_nobh, "nobh"}, 285 {Opt_user_xattr, "user_xattr"}, 286 {Opt_nouser_xattr, "nouser_xattr"}, 287 {Opt_acl, "acl"}, 288 {Opt_noacl, "noacl"}, 289 {Opt_ignore, "grpquota"}, 290 {Opt_ignore, "noquota"}, 291 {Opt_ignore, "quota"}, 292 {Opt_ignore, "usrquota"}, 293 {Opt_err, NULL} 294 }; 295 296 static int parse_options (char * options, 297 struct ext2_sb_info *sbi) 298 { 299 char * p; 300 substring_t args[MAX_OPT_ARGS]; 301 unsigned long kind = EXT2_MOUNT_ERRORS_CONT; 302 int option; 303 304 if (!options) 305 return 1; 306 307 while ((p = strsep (&options, ",")) != NULL) { 308 int token; 309 if (!*p) 310 continue; 311 312 token = match_token(p, tokens, args); 313 switch (token) { 314 case Opt_bsd_df: 315 clear_opt (sbi->s_mount_opt, MINIX_DF); 316 break; 317 case Opt_minix_df: 318 set_opt (sbi->s_mount_opt, MINIX_DF); 319 break; 320 case Opt_grpid: 321 set_opt (sbi->s_mount_opt, GRPID); 322 break; 323 case Opt_nogrpid: 324 clear_opt (sbi->s_mount_opt, GRPID); 325 break; 326 case Opt_resuid: 327 if (match_int(&args[0], &option)) 328 return 0; 329 sbi->s_resuid = option; 330 break; 331 case Opt_resgid: 332 if (match_int(&args[0], &option)) 333 return 0; 334 sbi->s_resgid = option; 335 break; 336 case Opt_sb: 337 /* handled by get_sb_block() instead of here */ 338 /* *sb_block = match_int(&args[0]); */ 339 break; 340 case Opt_err_panic: 341 kind = EXT2_MOUNT_ERRORS_PANIC; 342 break; 343 case Opt_err_ro: 344 kind = EXT2_MOUNT_ERRORS_RO; 345 break; 346 case Opt_err_cont: 347 kind = EXT2_MOUNT_ERRORS_CONT; 348 break; 349 case Opt_nouid32: 350 set_opt (sbi->s_mount_opt, NO_UID32); 351 break; 352 case Opt_check: 353 #ifdef CONFIG_EXT2_CHECK 354 set_opt (sbi->s_mount_opt, CHECK); 355 #else 356 printk("EXT2 Check option not supported\n"); 357 #endif 358 break; 359 case Opt_nocheck: 360 clear_opt (sbi->s_mount_opt, CHECK); 361 break; 362 case Opt_debug: 363 set_opt (sbi->s_mount_opt, DEBUG); 364 break; 365 case Opt_oldalloc: 366 set_opt (sbi->s_mount_opt, OLDALLOC); 367 break; 368 case Opt_orlov: 369 clear_opt (sbi->s_mount_opt, OLDALLOC); 370 break; 371 case Opt_nobh: 372 set_opt (sbi->s_mount_opt, NOBH); 373 break; 374 #ifdef CONFIG_EXT2_FS_XATTR 375 case Opt_user_xattr: 376 set_opt (sbi->s_mount_opt, XATTR_USER); 377 break; 378 case Opt_nouser_xattr: 379 clear_opt (sbi->s_mount_opt, XATTR_USER); 380 break; 381 #else 382 case Opt_user_xattr: 383 case Opt_nouser_xattr: 384 printk("EXT2 (no)user_xattr options not supported\n"); 385 break; 386 #endif 387 #ifdef CONFIG_EXT2_FS_POSIX_ACL 388 case Opt_acl: 389 set_opt(sbi->s_mount_opt, POSIX_ACL); 390 break; 391 case Opt_noacl: 392 clear_opt(sbi->s_mount_opt, POSIX_ACL); 393 break; 394 #else 395 case Opt_acl: 396 case Opt_noacl: 397 printk("EXT2 (no)acl options not supported\n"); 398 break; 399 #endif 400 case Opt_ignore: 401 break; 402 default: 403 return 0; 404 } 405 } 406 sbi->s_mount_opt |= kind; 407 return 1; 408 } 409 410 static int ext2_setup_super (struct super_block * sb, 411 struct ext2_super_block * es, 412 int read_only) 413 { 414 int res = 0; 415 struct ext2_sb_info *sbi = EXT2_SB(sb); 416 417 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 418 printk ("EXT2-fs warning: revision level too high, " 419 "forcing read-only mode\n"); 420 res = MS_RDONLY; 421 } 422 if (read_only) 423 return res; 424 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 425 printk ("EXT2-fs warning: mounting unchecked fs, " 426 "running e2fsck is recommended\n"); 427 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 428 printk ("EXT2-fs warning: mounting fs with errors, " 429 "running e2fsck is recommended\n"); 430 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 431 le16_to_cpu(es->s_mnt_count) >= 432 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 433 printk ("EXT2-fs warning: maximal mount count reached, " 434 "running e2fsck is recommended\n"); 435 else if (le32_to_cpu(es->s_checkinterval) && 436 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds())) 437 printk ("EXT2-fs warning: checktime reached, " 438 "running e2fsck is recommended\n"); 439 if (!le16_to_cpu(es->s_max_mnt_count)) 440 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 441 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1); 442 ext2_write_super(sb); 443 if (test_opt (sb, DEBUG)) 444 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, " 445 "bpg=%lu, ipg=%lu, mo=%04lx]\n", 446 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 447 sbi->s_frag_size, 448 sbi->s_groups_count, 449 EXT2_BLOCKS_PER_GROUP(sb), 450 EXT2_INODES_PER_GROUP(sb), 451 sbi->s_mount_opt); 452 #ifdef CONFIG_EXT2_CHECK 453 if (test_opt (sb, CHECK)) { 454 ext2_check_blocks_bitmap (sb); 455 ext2_check_inodes_bitmap (sb); 456 } 457 #endif 458 return res; 459 } 460 461 static int ext2_check_descriptors (struct super_block * sb) 462 { 463 int i; 464 int desc_block = 0; 465 struct ext2_sb_info *sbi = EXT2_SB(sb); 466 unsigned long block = le32_to_cpu(sbi->s_es->s_first_data_block); 467 struct ext2_group_desc * gdp = NULL; 468 469 ext2_debug ("Checking group descriptors"); 470 471 for (i = 0; i < sbi->s_groups_count; i++) 472 { 473 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0) 474 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data; 475 if (le32_to_cpu(gdp->bg_block_bitmap) < block || 476 le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb)) 477 { 478 ext2_error (sb, "ext2_check_descriptors", 479 "Block bitmap for group %d" 480 " not in group (block %lu)!", 481 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 482 return 0; 483 } 484 if (le32_to_cpu(gdp->bg_inode_bitmap) < block || 485 le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb)) 486 { 487 ext2_error (sb, "ext2_check_descriptors", 488 "Inode bitmap for group %d" 489 " not in group (block %lu)!", 490 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 491 return 0; 492 } 493 if (le32_to_cpu(gdp->bg_inode_table) < block || 494 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >= 495 block + EXT2_BLOCKS_PER_GROUP(sb)) 496 { 497 ext2_error (sb, "ext2_check_descriptors", 498 "Inode table for group %d" 499 " not in group (block %lu)!", 500 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 501 return 0; 502 } 503 block += EXT2_BLOCKS_PER_GROUP(sb); 504 gdp++; 505 } 506 return 1; 507 } 508 509 #define log2(n) ffz(~(n)) 510 511 /* 512 * Maximal file size. There is a direct, and {,double-,triple-}indirect 513 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 514 * We need to be 1 filesystem block less than the 2^32 sector limit. 515 */ 516 static loff_t ext2_max_size(int bits) 517 { 518 loff_t res = EXT2_NDIR_BLOCKS; 519 /* This constant is calculated to be the largest file size for a 520 * dense, 4k-blocksize file such that the total number of 521 * sectors in the file, including data and all indirect blocks, 522 * does not exceed 2^32. */ 523 const loff_t upper_limit = 0x1ff7fffd000LL; 524 525 res += 1LL << (bits-2); 526 res += 1LL << (2*(bits-2)); 527 res += 1LL << (3*(bits-2)); 528 res <<= bits; 529 if (res > upper_limit) 530 res = upper_limit; 531 return res; 532 } 533 534 static unsigned long descriptor_loc(struct super_block *sb, 535 unsigned long logic_sb_block, 536 int nr) 537 { 538 struct ext2_sb_info *sbi = EXT2_SB(sb); 539 unsigned long bg, first_data_block, first_meta_bg; 540 int has_super = 0; 541 542 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block); 543 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 544 545 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 546 nr < first_meta_bg) 547 return (logic_sb_block + nr + 1); 548 bg = sbi->s_desc_per_block * nr; 549 if (ext2_bg_has_super(sb, bg)) 550 has_super = 1; 551 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group)); 552 } 553 554 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 555 { 556 struct buffer_head * bh; 557 struct ext2_sb_info * sbi; 558 struct ext2_super_block * es; 559 struct inode *root; 560 unsigned long block; 561 unsigned long sb_block = get_sb_block(&data); 562 unsigned long logic_sb_block; 563 unsigned long offset = 0; 564 unsigned long def_mount_opts; 565 int blocksize = BLOCK_SIZE; 566 int db_count; 567 int i, j; 568 __le32 features; 569 570 sbi = kmalloc(sizeof(*sbi), GFP_KERNEL); 571 if (!sbi) 572 return -ENOMEM; 573 sb->s_fs_info = sbi; 574 memset(sbi, 0, sizeof(*sbi)); 575 576 /* 577 * See what the current blocksize for the device is, and 578 * use that as the blocksize. Otherwise (or if the blocksize 579 * is smaller than the default) use the default. 580 * This is important for devices that have a hardware 581 * sectorsize that is larger than the default. 582 */ 583 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 584 if (!blocksize) { 585 printk ("EXT2-fs: unable to set blocksize\n"); 586 goto failed_sbi; 587 } 588 589 /* 590 * If the superblock doesn't start on a hardware sector boundary, 591 * calculate the offset. 592 */ 593 if (blocksize != BLOCK_SIZE) { 594 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 595 offset = (sb_block*BLOCK_SIZE) % blocksize; 596 } else { 597 logic_sb_block = sb_block; 598 } 599 600 if (!(bh = sb_bread(sb, logic_sb_block))) { 601 printk ("EXT2-fs: unable to read superblock\n"); 602 goto failed_sbi; 603 } 604 /* 605 * Note: s_es must be initialized as soon as possible because 606 * some ext2 macro-instructions depend on its value 607 */ 608 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 609 sbi->s_es = es; 610 sb->s_magic = le16_to_cpu(es->s_magic); 611 612 if (sb->s_magic != EXT2_SUPER_MAGIC) 613 goto cantfind_ext2; 614 615 /* Set defaults before we parse the mount options */ 616 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 617 if (def_mount_opts & EXT2_DEFM_DEBUG) 618 set_opt(sbi->s_mount_opt, DEBUG); 619 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 620 set_opt(sbi->s_mount_opt, GRPID); 621 if (def_mount_opts & EXT2_DEFM_UID16) 622 set_opt(sbi->s_mount_opt, NO_UID32); 623 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 624 set_opt(sbi->s_mount_opt, XATTR_USER); 625 if (def_mount_opts & EXT2_DEFM_ACL) 626 set_opt(sbi->s_mount_opt, POSIX_ACL); 627 628 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 629 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 630 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO) 631 set_opt(sbi->s_mount_opt, ERRORS_RO); 632 633 sbi->s_resuid = le16_to_cpu(es->s_def_resuid); 634 sbi->s_resgid = le16_to_cpu(es->s_def_resgid); 635 636 if (!parse_options ((char *) data, sbi)) 637 goto failed_mount; 638 639 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 640 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 641 MS_POSIXACL : 0); 642 643 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 644 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 645 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 646 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 647 printk("EXT2-fs warning: feature flags set on rev 0 fs, " 648 "running e2fsck is recommended\n"); 649 /* 650 * Check feature flags regardless of the revision level, since we 651 * previously didn't change the revision level when setting the flags, 652 * so there is a chance incompat flags are set on a rev 0 filesystem. 653 */ 654 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 655 if (features) { 656 printk("EXT2-fs: %s: couldn't mount because of " 657 "unsupported optional features (%x).\n", 658 sb->s_id, le32_to_cpu(features)); 659 goto failed_mount; 660 } 661 if (!(sb->s_flags & MS_RDONLY) && 662 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 663 printk("EXT2-fs: %s: couldn't mount RDWR because of " 664 "unsupported optional features (%x).\n", 665 sb->s_id, le32_to_cpu(features)); 666 goto failed_mount; 667 } 668 669 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 670 671 /* If the blocksize doesn't match, re-read the thing.. */ 672 if (sb->s_blocksize != blocksize) { 673 brelse(bh); 674 675 if (!sb_set_blocksize(sb, blocksize)) { 676 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); 677 goto failed_sbi; 678 } 679 680 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 681 offset = (sb_block*BLOCK_SIZE) % blocksize; 682 bh = sb_bread(sb, logic_sb_block); 683 if(!bh) { 684 printk("EXT2-fs: Couldn't read superblock on " 685 "2nd try.\n"); 686 goto failed_sbi; 687 } 688 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 689 sbi->s_es = es; 690 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 691 printk ("EXT2-fs: Magic mismatch, very weird !\n"); 692 goto failed_mount; 693 } 694 } 695 696 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 697 698 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 699 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 700 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 701 } else { 702 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 703 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 704 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 705 (sbi->s_inode_size & (sbi->s_inode_size - 1)) || 706 (sbi->s_inode_size > blocksize)) { 707 printk ("EXT2-fs: unsupported inode size: %d\n", 708 sbi->s_inode_size); 709 goto failed_mount; 710 } 711 } 712 713 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 714 le32_to_cpu(es->s_log_frag_size); 715 if (sbi->s_frag_size == 0) 716 goto cantfind_ext2; 717 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 718 719 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 720 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 721 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 722 723 if (EXT2_INODE_SIZE(sb) == 0) 724 goto cantfind_ext2; 725 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 726 if (sbi->s_inodes_per_block == 0) 727 goto cantfind_ext2; 728 sbi->s_itb_per_group = sbi->s_inodes_per_group / 729 sbi->s_inodes_per_block; 730 sbi->s_desc_per_block = sb->s_blocksize / 731 sizeof (struct ext2_group_desc); 732 sbi->s_sbh = bh; 733 sbi->s_mount_state = le16_to_cpu(es->s_state); 734 sbi->s_addr_per_block_bits = 735 log2 (EXT2_ADDR_PER_BLOCK(sb)); 736 sbi->s_desc_per_block_bits = 737 log2 (EXT2_DESC_PER_BLOCK(sb)); 738 739 if (sb->s_magic != EXT2_SUPER_MAGIC) 740 goto cantfind_ext2; 741 742 if (sb->s_blocksize != bh->b_size) { 743 if (!silent) 744 printk ("VFS: Unsupported blocksize on dev " 745 "%s.\n", sb->s_id); 746 goto failed_mount; 747 } 748 749 if (sb->s_blocksize != sbi->s_frag_size) { 750 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n", 751 sbi->s_frag_size, sb->s_blocksize); 752 goto failed_mount; 753 } 754 755 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 756 printk ("EXT2-fs: #blocks per group too big: %lu\n", 757 sbi->s_blocks_per_group); 758 goto failed_mount; 759 } 760 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 761 printk ("EXT2-fs: #fragments per group too big: %lu\n", 762 sbi->s_frags_per_group); 763 goto failed_mount; 764 } 765 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 766 printk ("EXT2-fs: #inodes per group too big: %lu\n", 767 sbi->s_inodes_per_group); 768 goto failed_mount; 769 } 770 771 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 772 goto cantfind_ext2; 773 sbi->s_groups_count = (le32_to_cpu(es->s_blocks_count) - 774 le32_to_cpu(es->s_first_data_block) + 775 EXT2_BLOCKS_PER_GROUP(sb) - 1) / 776 EXT2_BLOCKS_PER_GROUP(sb); 777 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 778 EXT2_DESC_PER_BLOCK(sb); 779 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 780 if (sbi->s_group_desc == NULL) { 781 printk ("EXT2-fs: not enough memory\n"); 782 goto failed_mount; 783 } 784 percpu_counter_init(&sbi->s_freeblocks_counter); 785 percpu_counter_init(&sbi->s_freeinodes_counter); 786 percpu_counter_init(&sbi->s_dirs_counter); 787 bgl_lock_init(&sbi->s_blockgroup_lock); 788 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts), 789 GFP_KERNEL); 790 if (!sbi->s_debts) { 791 printk ("EXT2-fs: not enough memory\n"); 792 goto failed_mount_group_desc; 793 } 794 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts)); 795 for (i = 0; i < db_count; i++) { 796 block = descriptor_loc(sb, logic_sb_block, i); 797 sbi->s_group_desc[i] = sb_bread(sb, block); 798 if (!sbi->s_group_desc[i]) { 799 for (j = 0; j < i; j++) 800 brelse (sbi->s_group_desc[j]); 801 printk ("EXT2-fs: unable to read group descriptors\n"); 802 goto failed_mount_group_desc; 803 } 804 } 805 if (!ext2_check_descriptors (sb)) { 806 printk ("EXT2-fs: group descriptors corrupted!\n"); 807 db_count = i; 808 goto failed_mount2; 809 } 810 sbi->s_gdb_count = db_count; 811 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 812 spin_lock_init(&sbi->s_next_gen_lock); 813 /* 814 * set up enough so that it can read an inode 815 */ 816 sb->s_op = &ext2_sops; 817 sb->s_export_op = &ext2_export_ops; 818 sb->s_xattr = ext2_xattr_handlers; 819 root = iget(sb, EXT2_ROOT_INO); 820 sb->s_root = d_alloc_root(root); 821 if (!sb->s_root) { 822 iput(root); 823 printk(KERN_ERR "EXT2-fs: get root inode failed\n"); 824 goto failed_mount2; 825 } 826 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 827 dput(sb->s_root); 828 sb->s_root = NULL; 829 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n"); 830 goto failed_mount2; 831 } 832 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 833 ext2_warning(sb, __FUNCTION__, 834 "mounting ext3 filesystem as ext2\n"); 835 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); 836 percpu_counter_mod(&sbi->s_freeblocks_counter, 837 ext2_count_free_blocks(sb)); 838 percpu_counter_mod(&sbi->s_freeinodes_counter, 839 ext2_count_free_inodes(sb)); 840 percpu_counter_mod(&sbi->s_dirs_counter, 841 ext2_count_dirs(sb)); 842 return 0; 843 844 cantfind_ext2: 845 if (!silent) 846 printk("VFS: Can't find an ext2 filesystem on dev %s.\n", 847 sb->s_id); 848 goto failed_mount; 849 850 failed_mount2: 851 for (i = 0; i < db_count; i++) 852 brelse(sbi->s_group_desc[i]); 853 failed_mount_group_desc: 854 kfree(sbi->s_group_desc); 855 kfree(sbi->s_debts); 856 failed_mount: 857 brelse(bh); 858 failed_sbi: 859 sb->s_fs_info = NULL; 860 kfree(sbi); 861 return -EINVAL; 862 } 863 864 static void ext2_commit_super (struct super_block * sb, 865 struct ext2_super_block * es) 866 { 867 es->s_wtime = cpu_to_le32(get_seconds()); 868 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 869 sb->s_dirt = 0; 870 } 871 872 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) 873 { 874 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 875 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 876 es->s_wtime = cpu_to_le32(get_seconds()); 877 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 878 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 879 sb->s_dirt = 0; 880 } 881 882 /* 883 * In the second extended file system, it is not necessary to 884 * write the super block since we use a mapping of the 885 * disk super block in a buffer. 886 * 887 * However, this function is still used to set the fs valid 888 * flags to 0. We need to set this flag to 0 since the fs 889 * may have been checked while mounted and e2fsck may have 890 * set s_state to EXT2_VALID_FS after some corrections. 891 */ 892 893 void ext2_write_super (struct super_block * sb) 894 { 895 struct ext2_super_block * es; 896 lock_kernel(); 897 if (!(sb->s_flags & MS_RDONLY)) { 898 es = EXT2_SB(sb)->s_es; 899 900 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) { 901 ext2_debug ("setting valid to 0\n"); 902 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & 903 ~EXT2_VALID_FS); 904 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 905 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 906 es->s_mtime = cpu_to_le32(get_seconds()); 907 ext2_sync_super(sb, es); 908 } else 909 ext2_commit_super (sb, es); 910 } 911 sb->s_dirt = 0; 912 unlock_kernel(); 913 } 914 915 static int ext2_remount (struct super_block * sb, int * flags, char * data) 916 { 917 struct ext2_sb_info * sbi = EXT2_SB(sb); 918 struct ext2_super_block * es; 919 920 /* 921 * Allow the "check" option to be passed as a remount option. 922 */ 923 if (!parse_options (data, sbi)) 924 return -EINVAL; 925 926 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 927 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 928 929 es = sbi->s_es; 930 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 931 return 0; 932 if (*flags & MS_RDONLY) { 933 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 934 !(sbi->s_mount_state & EXT2_VALID_FS)) 935 return 0; 936 /* 937 * OK, we are remounting a valid rw partition rdonly, so set 938 * the rdonly flag and then mark the partition as valid again. 939 */ 940 es->s_state = cpu_to_le16(sbi->s_mount_state); 941 es->s_mtime = cpu_to_le32(get_seconds()); 942 } else { 943 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 944 ~EXT2_FEATURE_RO_COMPAT_SUPP); 945 if (ret) { 946 printk("EXT2-fs: %s: couldn't remount RDWR because of " 947 "unsupported optional features (%x).\n", 948 sb->s_id, le32_to_cpu(ret)); 949 return -EROFS; 950 } 951 /* 952 * Mounting a RDONLY partition read-write, so reread and 953 * store the current valid flag. (It may have been changed 954 * by e2fsck since we originally mounted the partition.) 955 */ 956 sbi->s_mount_state = le16_to_cpu(es->s_state); 957 if (!ext2_setup_super (sb, es, 0)) 958 sb->s_flags &= ~MS_RDONLY; 959 } 960 ext2_sync_super(sb, es); 961 return 0; 962 } 963 964 static int ext2_statfs (struct super_block * sb, struct kstatfs * buf) 965 { 966 struct ext2_sb_info *sbi = EXT2_SB(sb); 967 unsigned long overhead; 968 int i; 969 970 if (test_opt (sb, MINIX_DF)) 971 overhead = 0; 972 else { 973 /* 974 * Compute the overhead (FS structures) 975 */ 976 977 /* 978 * All of the blocks before first_data_block are 979 * overhead 980 */ 981 overhead = le32_to_cpu(sbi->s_es->s_first_data_block); 982 983 /* 984 * Add the overhead attributed to the superblock and 985 * block group descriptors. If the sparse superblocks 986 * feature is turned on, then not all groups have this. 987 */ 988 for (i = 0; i < sbi->s_groups_count; i++) 989 overhead += ext2_bg_has_super(sb, i) + 990 ext2_bg_num_gdb(sb, i); 991 992 /* 993 * Every block group has an inode bitmap, a block 994 * bitmap, and an inode table. 995 */ 996 overhead += (sbi->s_groups_count * 997 (2 + sbi->s_itb_per_group)); 998 } 999 1000 buf->f_type = EXT2_SUPER_MAGIC; 1001 buf->f_bsize = sb->s_blocksize; 1002 buf->f_blocks = le32_to_cpu(sbi->s_es->s_blocks_count) - overhead; 1003 buf->f_bfree = ext2_count_free_blocks(sb); 1004 buf->f_bavail = buf->f_bfree - le32_to_cpu(sbi->s_es->s_r_blocks_count); 1005 if (buf->f_bfree < le32_to_cpu(sbi->s_es->s_r_blocks_count)) 1006 buf->f_bavail = 0; 1007 buf->f_files = le32_to_cpu(sbi->s_es->s_inodes_count); 1008 buf->f_ffree = ext2_count_free_inodes (sb); 1009 buf->f_namelen = EXT2_NAME_LEN; 1010 return 0; 1011 } 1012 1013 static struct super_block *ext2_get_sb(struct file_system_type *fs_type, 1014 int flags, const char *dev_name, void *data) 1015 { 1016 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super); 1017 } 1018 1019 #ifdef CONFIG_QUOTA 1020 1021 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1022 * acquiring the locks... As quota files are never truncated and quota code 1023 * itself serializes the operations (and noone else should touch the files) 1024 * we don't have to be afraid of races */ 1025 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1026 size_t len, loff_t off) 1027 { 1028 struct inode *inode = sb_dqopt(sb)->files[type]; 1029 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1030 int err = 0; 1031 int offset = off & (sb->s_blocksize - 1); 1032 int tocopy; 1033 size_t toread; 1034 struct buffer_head tmp_bh; 1035 struct buffer_head *bh; 1036 loff_t i_size = i_size_read(inode); 1037 1038 if (off > i_size) 1039 return 0; 1040 if (off+len > i_size) 1041 len = i_size-off; 1042 toread = len; 1043 while (toread > 0) { 1044 tocopy = sb->s_blocksize - offset < toread ? 1045 sb->s_blocksize - offset : toread; 1046 1047 tmp_bh.b_state = 0; 1048 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1049 if (err) 1050 return err; 1051 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1052 memset(data, 0, tocopy); 1053 else { 1054 bh = sb_bread(sb, tmp_bh.b_blocknr); 1055 if (!bh) 1056 return -EIO; 1057 memcpy(data, bh->b_data+offset, tocopy); 1058 brelse(bh); 1059 } 1060 offset = 0; 1061 toread -= tocopy; 1062 data += tocopy; 1063 blk++; 1064 } 1065 return len; 1066 } 1067 1068 /* Write to quotafile */ 1069 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1070 const char *data, size_t len, loff_t off) 1071 { 1072 struct inode *inode = sb_dqopt(sb)->files[type]; 1073 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1074 int err = 0; 1075 int offset = off & (sb->s_blocksize - 1); 1076 int tocopy; 1077 size_t towrite = len; 1078 struct buffer_head tmp_bh; 1079 struct buffer_head *bh; 1080 1081 down(&inode->i_sem); 1082 while (towrite > 0) { 1083 tocopy = sb->s_blocksize - offset < towrite ? 1084 sb->s_blocksize - offset : towrite; 1085 1086 tmp_bh.b_state = 0; 1087 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1088 if (err) 1089 goto out; 1090 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1091 bh = sb_bread(sb, tmp_bh.b_blocknr); 1092 else 1093 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1094 if (!bh) { 1095 err = -EIO; 1096 goto out; 1097 } 1098 lock_buffer(bh); 1099 memcpy(bh->b_data+offset, data, tocopy); 1100 flush_dcache_page(bh->b_page); 1101 set_buffer_uptodate(bh); 1102 mark_buffer_dirty(bh); 1103 unlock_buffer(bh); 1104 brelse(bh); 1105 offset = 0; 1106 towrite -= tocopy; 1107 data += tocopy; 1108 blk++; 1109 } 1110 out: 1111 if (len == towrite) 1112 return err; 1113 if (inode->i_size < off+len-towrite) 1114 i_size_write(inode, off+len-towrite); 1115 inode->i_version++; 1116 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1117 mark_inode_dirty(inode); 1118 up(&inode->i_sem); 1119 return len - towrite; 1120 } 1121 1122 #endif 1123 1124 static struct file_system_type ext2_fs_type = { 1125 .owner = THIS_MODULE, 1126 .name = "ext2", 1127 .get_sb = ext2_get_sb, 1128 .kill_sb = kill_block_super, 1129 .fs_flags = FS_REQUIRES_DEV, 1130 }; 1131 1132 static int __init init_ext2_fs(void) 1133 { 1134 int err = init_ext2_xattr(); 1135 if (err) 1136 return err; 1137 err = init_inodecache(); 1138 if (err) 1139 goto out1; 1140 err = register_filesystem(&ext2_fs_type); 1141 if (err) 1142 goto out; 1143 return 0; 1144 out: 1145 destroy_inodecache(); 1146 out1: 1147 exit_ext2_xattr(); 1148 return err; 1149 } 1150 1151 static void __exit exit_ext2_fs(void) 1152 { 1153 unregister_filesystem(&ext2_fs_type); 1154 destroy_inodecache(); 1155 exit_ext2_xattr(); 1156 } 1157 1158 module_init(init_ext2_fs) 1159 module_exit(exit_ext2_fs) 1160