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/smp_lock.h> 30 #include <linux/vfs.h> 31 #include <linux/seq_file.h> 32 #include <linux/mount.h> 33 #include <linux/log2.h> 34 #include <linux/quotaops.h> 35 #include <asm/uaccess.h> 36 #include "ext2.h" 37 #include "xattr.h" 38 #include "acl.h" 39 #include "xip.h" 40 41 static void ext2_sync_super(struct super_block *sb, 42 struct ext2_super_block *es); 43 static int ext2_remount (struct super_block * sb, int * flags, char * data); 44 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf); 45 static int ext2_sync_fs(struct super_block *sb, int wait); 46 47 void ext2_error (struct super_block * sb, const char * function, 48 const char * fmt, ...) 49 { 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 sbi->s_mount_state |= EXT2_ERROR_FS; 56 es->s_state |= cpu_to_le16(EXT2_ERROR_FS); 57 ext2_sync_super(sb, es); 58 } 59 60 va_start(args, fmt); 61 printk(KERN_CRIT "EXT2-fs (%s): error: %s: ", sb->s_id, function); 62 vprintk(fmt, args); 63 printk("\n"); 64 va_end(args); 65 66 if (test_opt(sb, ERRORS_PANIC)) 67 panic("EXT2-fs: panic from previous error\n"); 68 if (test_opt(sb, ERRORS_RO)) { 69 ext2_msg(sb, KERN_CRIT, 70 "error: remounting filesystem read-only"); 71 sb->s_flags |= MS_RDONLY; 72 } 73 } 74 75 void ext2_msg(struct super_block *sb, const char *prefix, 76 const char *fmt, ...) 77 { 78 va_list args; 79 80 va_start(args, fmt); 81 printk("%sEXT2-fs (%s): ", prefix, sb->s_id); 82 vprintk(fmt, args); 83 printk("\n"); 84 va_end(args); 85 } 86 87 void ext2_update_dynamic_rev(struct super_block *sb) 88 { 89 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 90 91 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) 92 return; 93 94 ext2_msg(sb, KERN_WARNING, 95 "warning: updating to rev %d because of " 96 "new feature flag, running e2fsck is recommended", 97 EXT2_DYNAMIC_REV); 98 99 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); 100 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); 101 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); 102 /* leave es->s_feature_*compat flags alone */ 103 /* es->s_uuid will be set by e2fsck if empty */ 104 105 /* 106 * The rest of the superblock fields should be zero, and if not it 107 * means they are likely already in use, so leave them alone. We 108 * can leave it up to e2fsck to clean up any inconsistencies there. 109 */ 110 } 111 112 static void ext2_put_super (struct super_block * sb) 113 { 114 int db_count; 115 int i; 116 struct ext2_sb_info *sbi = EXT2_SB(sb); 117 118 lock_kernel(); 119 120 if (sb->s_dirt) 121 ext2_write_super(sb); 122 123 ext2_xattr_put_super(sb); 124 if (!(sb->s_flags & MS_RDONLY)) { 125 struct ext2_super_block *es = sbi->s_es; 126 127 es->s_state = cpu_to_le16(sbi->s_mount_state); 128 ext2_sync_super(sb, es); 129 } 130 db_count = sbi->s_gdb_count; 131 for (i = 0; i < db_count; i++) 132 if (sbi->s_group_desc[i]) 133 brelse (sbi->s_group_desc[i]); 134 kfree(sbi->s_group_desc); 135 kfree(sbi->s_debts); 136 percpu_counter_destroy(&sbi->s_freeblocks_counter); 137 percpu_counter_destroy(&sbi->s_freeinodes_counter); 138 percpu_counter_destroy(&sbi->s_dirs_counter); 139 brelse (sbi->s_sbh); 140 sb->s_fs_info = NULL; 141 kfree(sbi->s_blockgroup_lock); 142 kfree(sbi); 143 144 unlock_kernel(); 145 } 146 147 static struct kmem_cache * ext2_inode_cachep; 148 149 static struct inode *ext2_alloc_inode(struct super_block *sb) 150 { 151 struct ext2_inode_info *ei; 152 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL); 153 if (!ei) 154 return NULL; 155 ei->i_block_alloc_info = NULL; 156 ei->vfs_inode.i_version = 1; 157 return &ei->vfs_inode; 158 } 159 160 static void ext2_destroy_inode(struct inode *inode) 161 { 162 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 163 } 164 165 static void init_once(void *foo) 166 { 167 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 168 169 rwlock_init(&ei->i_meta_lock); 170 #ifdef CONFIG_EXT2_FS_XATTR 171 init_rwsem(&ei->xattr_sem); 172 #endif 173 mutex_init(&ei->truncate_mutex); 174 inode_init_once(&ei->vfs_inode); 175 } 176 177 static int init_inodecache(void) 178 { 179 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 180 sizeof(struct ext2_inode_info), 181 0, (SLAB_RECLAIM_ACCOUNT| 182 SLAB_MEM_SPREAD), 183 init_once); 184 if (ext2_inode_cachep == NULL) 185 return -ENOMEM; 186 return 0; 187 } 188 189 static void destroy_inodecache(void) 190 { 191 kmem_cache_destroy(ext2_inode_cachep); 192 } 193 194 static void ext2_clear_inode(struct inode *inode) 195 { 196 struct ext2_block_alloc_info *rsv = EXT2_I(inode)->i_block_alloc_info; 197 198 dquot_drop(inode); 199 ext2_discard_reservation(inode); 200 EXT2_I(inode)->i_block_alloc_info = NULL; 201 if (unlikely(rsv)) 202 kfree(rsv); 203 } 204 205 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs) 206 { 207 struct super_block *sb = vfs->mnt_sb; 208 struct ext2_sb_info *sbi = EXT2_SB(sb); 209 struct ext2_super_block *es = sbi->s_es; 210 unsigned long def_mount_opts; 211 212 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 213 214 if (sbi->s_sb_block != 1) 215 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 216 if (test_opt(sb, MINIX_DF)) 217 seq_puts(seq, ",minixdf"); 218 if (test_opt(sb, GRPID)) 219 seq_puts(seq, ",grpid"); 220 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 221 seq_puts(seq, ",nogrpid"); 222 if (sbi->s_resuid != EXT2_DEF_RESUID || 223 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 224 seq_printf(seq, ",resuid=%u", sbi->s_resuid); 225 } 226 if (sbi->s_resgid != EXT2_DEF_RESGID || 227 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 228 seq_printf(seq, ",resgid=%u", sbi->s_resgid); 229 } 230 if (test_opt(sb, ERRORS_RO)) { 231 int def_errors = le16_to_cpu(es->s_errors); 232 233 if (def_errors == EXT2_ERRORS_PANIC || 234 def_errors == EXT2_ERRORS_CONTINUE) { 235 seq_puts(seq, ",errors=remount-ro"); 236 } 237 } 238 if (test_opt(sb, ERRORS_CONT)) 239 seq_puts(seq, ",errors=continue"); 240 if (test_opt(sb, ERRORS_PANIC)) 241 seq_puts(seq, ",errors=panic"); 242 if (test_opt(sb, NO_UID32)) 243 seq_puts(seq, ",nouid32"); 244 if (test_opt(sb, DEBUG)) 245 seq_puts(seq, ",debug"); 246 if (test_opt(sb, OLDALLOC)) 247 seq_puts(seq, ",oldalloc"); 248 249 #ifdef CONFIG_EXT2_FS_XATTR 250 if (test_opt(sb, XATTR_USER)) 251 seq_puts(seq, ",user_xattr"); 252 if (!test_opt(sb, XATTR_USER) && 253 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 254 seq_puts(seq, ",nouser_xattr"); 255 } 256 #endif 257 258 #ifdef CONFIG_EXT2_FS_POSIX_ACL 259 if (test_opt(sb, POSIX_ACL)) 260 seq_puts(seq, ",acl"); 261 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 262 seq_puts(seq, ",noacl"); 263 #endif 264 265 if (test_opt(sb, NOBH)) 266 seq_puts(seq, ",nobh"); 267 268 #if defined(CONFIG_QUOTA) 269 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 270 seq_puts(seq, ",usrquota"); 271 272 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 273 seq_puts(seq, ",grpquota"); 274 #endif 275 276 #if defined(CONFIG_EXT2_FS_XIP) 277 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 278 seq_puts(seq, ",xip"); 279 #endif 280 281 if (!test_opt(sb, RESERVATION)) 282 seq_puts(seq, ",noreservation"); 283 284 return 0; 285 } 286 287 #ifdef CONFIG_QUOTA 288 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 289 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 290 #endif 291 292 static const struct super_operations ext2_sops = { 293 .alloc_inode = ext2_alloc_inode, 294 .destroy_inode = ext2_destroy_inode, 295 .write_inode = ext2_write_inode, 296 .delete_inode = ext2_delete_inode, 297 .put_super = ext2_put_super, 298 .write_super = ext2_write_super, 299 .sync_fs = ext2_sync_fs, 300 .statfs = ext2_statfs, 301 .remount_fs = ext2_remount, 302 .clear_inode = ext2_clear_inode, 303 .show_options = ext2_show_options, 304 #ifdef CONFIG_QUOTA 305 .quota_read = ext2_quota_read, 306 .quota_write = ext2_quota_write, 307 #endif 308 }; 309 310 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 311 u64 ino, u32 generation) 312 { 313 struct inode *inode; 314 315 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 316 return ERR_PTR(-ESTALE); 317 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 318 return ERR_PTR(-ESTALE); 319 320 /* iget isn't really right if the inode is currently unallocated!! 321 * ext2_read_inode currently does appropriate checks, but 322 * it might be "neater" to call ext2_get_inode first and check 323 * if the inode is valid..... 324 */ 325 inode = ext2_iget(sb, ino); 326 if (IS_ERR(inode)) 327 return ERR_CAST(inode); 328 if (generation && inode->i_generation != generation) { 329 /* we didn't find the right inode.. */ 330 iput(inode); 331 return ERR_PTR(-ESTALE); 332 } 333 return inode; 334 } 335 336 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 337 int fh_len, int fh_type) 338 { 339 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 340 ext2_nfs_get_inode); 341 } 342 343 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 344 int fh_len, int fh_type) 345 { 346 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 347 ext2_nfs_get_inode); 348 } 349 350 /* Yes, most of these are left as NULL!! 351 * A NULL value implies the default, which works with ext2-like file 352 * systems, but can be improved upon. 353 * Currently only get_parent is required. 354 */ 355 static const struct export_operations ext2_export_ops = { 356 .fh_to_dentry = ext2_fh_to_dentry, 357 .fh_to_parent = ext2_fh_to_parent, 358 .get_parent = ext2_get_parent, 359 }; 360 361 static unsigned long get_sb_block(void **data) 362 { 363 unsigned long sb_block; 364 char *options = (char *) *data; 365 366 if (!options || strncmp(options, "sb=", 3) != 0) 367 return 1; /* Default location */ 368 options += 3; 369 sb_block = simple_strtoul(options, &options, 0); 370 if (*options && *options != ',') { 371 printk("EXT2-fs: Invalid sb specification: %s\n", 372 (char *) *data); 373 return 1; 374 } 375 if (*options == ',') 376 options++; 377 *data = (void *) options; 378 return sb_block; 379 } 380 381 enum { 382 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 383 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 384 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 385 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 386 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, 387 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 388 }; 389 390 static const match_table_t tokens = { 391 {Opt_bsd_df, "bsddf"}, 392 {Opt_minix_df, "minixdf"}, 393 {Opt_grpid, "grpid"}, 394 {Opt_grpid, "bsdgroups"}, 395 {Opt_nogrpid, "nogrpid"}, 396 {Opt_nogrpid, "sysvgroups"}, 397 {Opt_resgid, "resgid=%u"}, 398 {Opt_resuid, "resuid=%u"}, 399 {Opt_sb, "sb=%u"}, 400 {Opt_err_cont, "errors=continue"}, 401 {Opt_err_panic, "errors=panic"}, 402 {Opt_err_ro, "errors=remount-ro"}, 403 {Opt_nouid32, "nouid32"}, 404 {Opt_nocheck, "check=none"}, 405 {Opt_nocheck, "nocheck"}, 406 {Opt_debug, "debug"}, 407 {Opt_oldalloc, "oldalloc"}, 408 {Opt_orlov, "orlov"}, 409 {Opt_nobh, "nobh"}, 410 {Opt_user_xattr, "user_xattr"}, 411 {Opt_nouser_xattr, "nouser_xattr"}, 412 {Opt_acl, "acl"}, 413 {Opt_noacl, "noacl"}, 414 {Opt_xip, "xip"}, 415 {Opt_grpquota, "grpquota"}, 416 {Opt_ignore, "noquota"}, 417 {Opt_quota, "quota"}, 418 {Opt_usrquota, "usrquota"}, 419 {Opt_reservation, "reservation"}, 420 {Opt_noreservation, "noreservation"}, 421 {Opt_err, NULL} 422 }; 423 424 static int parse_options(char *options, struct super_block *sb) 425 { 426 char *p; 427 struct ext2_sb_info *sbi = EXT2_SB(sb); 428 substring_t args[MAX_OPT_ARGS]; 429 int option; 430 431 if (!options) 432 return 1; 433 434 while ((p = strsep (&options, ",")) != NULL) { 435 int token; 436 if (!*p) 437 continue; 438 439 token = match_token(p, tokens, args); 440 switch (token) { 441 case Opt_bsd_df: 442 clear_opt (sbi->s_mount_opt, MINIX_DF); 443 break; 444 case Opt_minix_df: 445 set_opt (sbi->s_mount_opt, MINIX_DF); 446 break; 447 case Opt_grpid: 448 set_opt (sbi->s_mount_opt, GRPID); 449 break; 450 case Opt_nogrpid: 451 clear_opt (sbi->s_mount_opt, GRPID); 452 break; 453 case Opt_resuid: 454 if (match_int(&args[0], &option)) 455 return 0; 456 sbi->s_resuid = option; 457 break; 458 case Opt_resgid: 459 if (match_int(&args[0], &option)) 460 return 0; 461 sbi->s_resgid = option; 462 break; 463 case Opt_sb: 464 /* handled by get_sb_block() instead of here */ 465 /* *sb_block = match_int(&args[0]); */ 466 break; 467 case Opt_err_panic: 468 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 469 clear_opt (sbi->s_mount_opt, ERRORS_RO); 470 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 471 break; 472 case Opt_err_ro: 473 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 474 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 475 set_opt (sbi->s_mount_opt, ERRORS_RO); 476 break; 477 case Opt_err_cont: 478 clear_opt (sbi->s_mount_opt, ERRORS_RO); 479 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 480 set_opt (sbi->s_mount_opt, ERRORS_CONT); 481 break; 482 case Opt_nouid32: 483 set_opt (sbi->s_mount_opt, NO_UID32); 484 break; 485 case Opt_nocheck: 486 clear_opt (sbi->s_mount_opt, CHECK); 487 break; 488 case Opt_debug: 489 set_opt (sbi->s_mount_opt, DEBUG); 490 break; 491 case Opt_oldalloc: 492 set_opt (sbi->s_mount_opt, OLDALLOC); 493 break; 494 case Opt_orlov: 495 clear_opt (sbi->s_mount_opt, OLDALLOC); 496 break; 497 case Opt_nobh: 498 set_opt (sbi->s_mount_opt, NOBH); 499 break; 500 #ifdef CONFIG_EXT2_FS_XATTR 501 case Opt_user_xattr: 502 set_opt (sbi->s_mount_opt, XATTR_USER); 503 break; 504 case Opt_nouser_xattr: 505 clear_opt (sbi->s_mount_opt, XATTR_USER); 506 break; 507 #else 508 case Opt_user_xattr: 509 case Opt_nouser_xattr: 510 ext2_msg(sb, KERN_INFO, "(no)user_xattr options" 511 "not supported"); 512 break; 513 #endif 514 #ifdef CONFIG_EXT2_FS_POSIX_ACL 515 case Opt_acl: 516 set_opt(sbi->s_mount_opt, POSIX_ACL); 517 break; 518 case Opt_noacl: 519 clear_opt(sbi->s_mount_opt, POSIX_ACL); 520 break; 521 #else 522 case Opt_acl: 523 case Opt_noacl: 524 ext2_msg(sb, KERN_INFO, 525 "(no)acl options not supported"); 526 break; 527 #endif 528 case Opt_xip: 529 #ifdef CONFIG_EXT2_FS_XIP 530 set_opt (sbi->s_mount_opt, XIP); 531 #else 532 ext2_msg(sb, KERN_INFO, "xip option not supported"); 533 #endif 534 break; 535 536 #if defined(CONFIG_QUOTA) 537 case Opt_quota: 538 case Opt_usrquota: 539 set_opt(sbi->s_mount_opt, USRQUOTA); 540 break; 541 542 case Opt_grpquota: 543 set_opt(sbi->s_mount_opt, GRPQUOTA); 544 break; 545 #else 546 case Opt_quota: 547 case Opt_usrquota: 548 case Opt_grpquota: 549 ext2_msg(sb, KERN_INFO, 550 "quota operations not supported"); 551 break; 552 #endif 553 554 case Opt_reservation: 555 set_opt(sbi->s_mount_opt, RESERVATION); 556 ext2_msg(sb, KERN_INFO, "reservations ON"); 557 break; 558 case Opt_noreservation: 559 clear_opt(sbi->s_mount_opt, RESERVATION); 560 ext2_msg(sb, KERN_INFO, "reservations OFF"); 561 break; 562 case Opt_ignore: 563 break; 564 default: 565 return 0; 566 } 567 } 568 return 1; 569 } 570 571 static int ext2_setup_super (struct super_block * sb, 572 struct ext2_super_block * es, 573 int read_only) 574 { 575 int res = 0; 576 struct ext2_sb_info *sbi = EXT2_SB(sb); 577 578 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 579 ext2_msg(sb, KERN_ERR, 580 "error: revision level too high, " 581 "forcing read-only mode"); 582 res = MS_RDONLY; 583 } 584 if (read_only) 585 return res; 586 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 587 ext2_msg(sb, KERN_WARNING, 588 "warning: mounting unchecked fs, " 589 "running e2fsck is recommended"); 590 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 591 ext2_msg(sb, KERN_WARNING, 592 "warning: mounting fs with errors, " 593 "running e2fsck is recommended"); 594 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 595 le16_to_cpu(es->s_mnt_count) >= 596 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 597 ext2_msg(sb, KERN_WARNING, 598 "warning: maximal mount count reached, " 599 "running e2fsck is recommended"); 600 else if (le32_to_cpu(es->s_checkinterval) && 601 (le32_to_cpu(es->s_lastcheck) + 602 le32_to_cpu(es->s_checkinterval) <= get_seconds())) 603 ext2_msg(sb, KERN_WARNING, 604 "warning: checktime reached, " 605 "running e2fsck is recommended"); 606 if (!le16_to_cpu(es->s_max_mnt_count)) 607 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 608 le16_add_cpu(&es->s_mnt_count, 1); 609 ext2_write_super(sb); 610 if (test_opt (sb, DEBUG)) 611 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, " 612 "bpg=%lu, ipg=%lu, mo=%04lx]", 613 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 614 sbi->s_frag_size, 615 sbi->s_groups_count, 616 EXT2_BLOCKS_PER_GROUP(sb), 617 EXT2_INODES_PER_GROUP(sb), 618 sbi->s_mount_opt); 619 return res; 620 } 621 622 static int ext2_check_descriptors(struct super_block *sb) 623 { 624 int i; 625 struct ext2_sb_info *sbi = EXT2_SB(sb); 626 627 ext2_debug ("Checking group descriptors"); 628 629 for (i = 0; i < sbi->s_groups_count; i++) { 630 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 631 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 632 ext2_fsblk_t last_block; 633 634 if (i == sbi->s_groups_count - 1) 635 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 636 else 637 last_block = first_block + 638 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 639 640 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 641 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 642 { 643 ext2_error (sb, "ext2_check_descriptors", 644 "Block bitmap for group %d" 645 " not in group (block %lu)!", 646 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 647 return 0; 648 } 649 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 650 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 651 { 652 ext2_error (sb, "ext2_check_descriptors", 653 "Inode bitmap for group %d" 654 " not in group (block %lu)!", 655 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 656 return 0; 657 } 658 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 659 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 660 last_block) 661 { 662 ext2_error (sb, "ext2_check_descriptors", 663 "Inode table for group %d" 664 " not in group (block %lu)!", 665 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 666 return 0; 667 } 668 } 669 return 1; 670 } 671 672 /* 673 * Maximal file size. There is a direct, and {,double-,triple-}indirect 674 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 675 * We need to be 1 filesystem block less than the 2^32 sector limit. 676 */ 677 static loff_t ext2_max_size(int bits) 678 { 679 loff_t res = EXT2_NDIR_BLOCKS; 680 int meta_blocks; 681 loff_t upper_limit; 682 683 /* This is calculated to be the largest file size for a 684 * dense, file such that the total number of 685 * sectors in the file, including data and all indirect blocks, 686 * does not exceed 2^32 -1 687 * __u32 i_blocks representing the total number of 688 * 512 bytes blocks of the file 689 */ 690 upper_limit = (1LL << 32) - 1; 691 692 /* total blocks in file system block size */ 693 upper_limit >>= (bits - 9); 694 695 696 /* indirect blocks */ 697 meta_blocks = 1; 698 /* double indirect blocks */ 699 meta_blocks += 1 + (1LL << (bits-2)); 700 /* tripple indirect blocks */ 701 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2))); 702 703 upper_limit -= meta_blocks; 704 upper_limit <<= bits; 705 706 res += 1LL << (bits-2); 707 res += 1LL << (2*(bits-2)); 708 res += 1LL << (3*(bits-2)); 709 res <<= bits; 710 if (res > upper_limit) 711 res = upper_limit; 712 713 if (res > MAX_LFS_FILESIZE) 714 res = MAX_LFS_FILESIZE; 715 716 return res; 717 } 718 719 static unsigned long descriptor_loc(struct super_block *sb, 720 unsigned long logic_sb_block, 721 int nr) 722 { 723 struct ext2_sb_info *sbi = EXT2_SB(sb); 724 unsigned long bg, first_meta_bg; 725 int has_super = 0; 726 727 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 728 729 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 730 nr < first_meta_bg) 731 return (logic_sb_block + nr + 1); 732 bg = sbi->s_desc_per_block * nr; 733 if (ext2_bg_has_super(sb, bg)) 734 has_super = 1; 735 736 return ext2_group_first_block_no(sb, bg) + has_super; 737 } 738 739 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 740 { 741 struct buffer_head * bh; 742 struct ext2_sb_info * sbi; 743 struct ext2_super_block * es; 744 struct inode *root; 745 unsigned long block; 746 unsigned long sb_block = get_sb_block(&data); 747 unsigned long logic_sb_block; 748 unsigned long offset = 0; 749 unsigned long def_mount_opts; 750 long ret = -EINVAL; 751 int blocksize = BLOCK_SIZE; 752 int db_count; 753 int i, j; 754 __le32 features; 755 int err; 756 757 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 758 if (!sbi) 759 return -ENOMEM; 760 761 sbi->s_blockgroup_lock = 762 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 763 if (!sbi->s_blockgroup_lock) { 764 kfree(sbi); 765 return -ENOMEM; 766 } 767 sb->s_fs_info = sbi; 768 sbi->s_sb_block = sb_block; 769 770 /* 771 * See what the current blocksize for the device is, and 772 * use that as the blocksize. Otherwise (or if the blocksize 773 * is smaller than the default) use the default. 774 * This is important for devices that have a hardware 775 * sectorsize that is larger than the default. 776 */ 777 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 778 if (!blocksize) { 779 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize"); 780 goto failed_sbi; 781 } 782 783 /* 784 * If the superblock doesn't start on a hardware sector boundary, 785 * calculate the offset. 786 */ 787 if (blocksize != BLOCK_SIZE) { 788 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 789 offset = (sb_block*BLOCK_SIZE) % blocksize; 790 } else { 791 logic_sb_block = sb_block; 792 } 793 794 if (!(bh = sb_bread(sb, logic_sb_block))) { 795 ext2_msg(sb, KERN_ERR, "error: unable to read superblock"); 796 goto failed_sbi; 797 } 798 /* 799 * Note: s_es must be initialized as soon as possible because 800 * some ext2 macro-instructions depend on its value 801 */ 802 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 803 sbi->s_es = es; 804 sb->s_magic = le16_to_cpu(es->s_magic); 805 806 if (sb->s_magic != EXT2_SUPER_MAGIC) 807 goto cantfind_ext2; 808 809 /* Set defaults before we parse the mount options */ 810 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 811 if (def_mount_opts & EXT2_DEFM_DEBUG) 812 set_opt(sbi->s_mount_opt, DEBUG); 813 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 814 set_opt(sbi->s_mount_opt, GRPID); 815 if (def_mount_opts & EXT2_DEFM_UID16) 816 set_opt(sbi->s_mount_opt, NO_UID32); 817 #ifdef CONFIG_EXT2_FS_XATTR 818 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 819 set_opt(sbi->s_mount_opt, XATTR_USER); 820 #endif 821 #ifdef CONFIG_EXT2_FS_POSIX_ACL 822 if (def_mount_opts & EXT2_DEFM_ACL) 823 set_opt(sbi->s_mount_opt, POSIX_ACL); 824 #endif 825 826 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 827 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 828 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 829 set_opt(sbi->s_mount_opt, ERRORS_CONT); 830 else 831 set_opt(sbi->s_mount_opt, ERRORS_RO); 832 833 sbi->s_resuid = le16_to_cpu(es->s_def_resuid); 834 sbi->s_resgid = le16_to_cpu(es->s_def_resgid); 835 836 set_opt(sbi->s_mount_opt, RESERVATION); 837 838 if (!parse_options((char *) data, sb)) 839 goto failed_mount; 840 841 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 842 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 843 MS_POSIXACL : 0); 844 845 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 846 EXT2_MOUNT_XIP if not */ 847 848 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 849 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 850 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 851 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 852 ext2_msg(sb, KERN_WARNING, 853 "warning: feature flags set on rev 0 fs, " 854 "running e2fsck is recommended"); 855 /* 856 * Check feature flags regardless of the revision level, since we 857 * previously didn't change the revision level when setting the flags, 858 * so there is a chance incompat flags are set on a rev 0 filesystem. 859 */ 860 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 861 if (features) { 862 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of " 863 "unsupported optional features (%x)", 864 le32_to_cpu(features)); 865 goto failed_mount; 866 } 867 if (!(sb->s_flags & MS_RDONLY) && 868 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 869 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of " 870 "unsupported optional features (%x)", 871 le32_to_cpu(features)); 872 goto failed_mount; 873 } 874 875 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 876 877 if (ext2_use_xip(sb) && blocksize != PAGE_SIZE) { 878 if (!silent) 879 ext2_msg(sb, KERN_ERR, 880 "error: unsupported blocksize for xip"); 881 goto failed_mount; 882 } 883 884 /* If the blocksize doesn't match, re-read the thing.. */ 885 if (sb->s_blocksize != blocksize) { 886 brelse(bh); 887 888 if (!sb_set_blocksize(sb, blocksize)) { 889 ext2_msg(sb, KERN_ERR, "error: blocksize is too small"); 890 goto failed_sbi; 891 } 892 893 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 894 offset = (sb_block*BLOCK_SIZE) % blocksize; 895 bh = sb_bread(sb, logic_sb_block); 896 if(!bh) { 897 ext2_msg(sb, KERN_ERR, "error: couldn't read" 898 "superblock on 2nd try"); 899 goto failed_sbi; 900 } 901 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 902 sbi->s_es = es; 903 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 904 ext2_msg(sb, KERN_ERR, "error: magic mismatch"); 905 goto failed_mount; 906 } 907 } 908 909 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 910 911 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 912 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 913 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 914 } else { 915 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 916 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 917 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 918 !is_power_of_2(sbi->s_inode_size) || 919 (sbi->s_inode_size > blocksize)) { 920 ext2_msg(sb, KERN_ERR, 921 "error: unsupported inode size: %d", 922 sbi->s_inode_size); 923 goto failed_mount; 924 } 925 } 926 927 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 928 le32_to_cpu(es->s_log_frag_size); 929 if (sbi->s_frag_size == 0) 930 goto cantfind_ext2; 931 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 932 933 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 934 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 935 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 936 937 if (EXT2_INODE_SIZE(sb) == 0) 938 goto cantfind_ext2; 939 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 940 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 941 goto cantfind_ext2; 942 sbi->s_itb_per_group = sbi->s_inodes_per_group / 943 sbi->s_inodes_per_block; 944 sbi->s_desc_per_block = sb->s_blocksize / 945 sizeof (struct ext2_group_desc); 946 sbi->s_sbh = bh; 947 sbi->s_mount_state = le16_to_cpu(es->s_state); 948 sbi->s_addr_per_block_bits = 949 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 950 sbi->s_desc_per_block_bits = 951 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 952 953 if (sb->s_magic != EXT2_SUPER_MAGIC) 954 goto cantfind_ext2; 955 956 if (sb->s_blocksize != bh->b_size) { 957 if (!silent) 958 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize"); 959 goto failed_mount; 960 } 961 962 if (sb->s_blocksize != sbi->s_frag_size) { 963 ext2_msg(sb, KERN_ERR, 964 "error: fragsize %lu != blocksize %lu" 965 "(not supported yet)", 966 sbi->s_frag_size, sb->s_blocksize); 967 goto failed_mount; 968 } 969 970 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 971 ext2_msg(sb, KERN_ERR, 972 "error: #blocks per group too big: %lu", 973 sbi->s_blocks_per_group); 974 goto failed_mount; 975 } 976 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 977 ext2_msg(sb, KERN_ERR, 978 "error: #fragments per group too big: %lu", 979 sbi->s_frags_per_group); 980 goto failed_mount; 981 } 982 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 983 ext2_msg(sb, KERN_ERR, 984 "error: #inodes per group too big: %lu", 985 sbi->s_inodes_per_group); 986 goto failed_mount; 987 } 988 989 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 990 goto cantfind_ext2; 991 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 992 le32_to_cpu(es->s_first_data_block) - 1) 993 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 994 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 995 EXT2_DESC_PER_BLOCK(sb); 996 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 997 if (sbi->s_group_desc == NULL) { 998 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 999 goto failed_mount; 1000 } 1001 bgl_lock_init(sbi->s_blockgroup_lock); 1002 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 1003 if (!sbi->s_debts) { 1004 ext2_msg(sb, KERN_ERR, "error: not enough memory"); 1005 goto failed_mount_group_desc; 1006 } 1007 for (i = 0; i < db_count; i++) { 1008 block = descriptor_loc(sb, logic_sb_block, i); 1009 sbi->s_group_desc[i] = sb_bread(sb, block); 1010 if (!sbi->s_group_desc[i]) { 1011 for (j = 0; j < i; j++) 1012 brelse (sbi->s_group_desc[j]); 1013 ext2_msg(sb, KERN_ERR, 1014 "error: unable to read group descriptors"); 1015 goto failed_mount_group_desc; 1016 } 1017 } 1018 if (!ext2_check_descriptors (sb)) { 1019 ext2_msg(sb, KERN_ERR, "group descriptors corrupted"); 1020 goto failed_mount2; 1021 } 1022 sbi->s_gdb_count = db_count; 1023 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1024 spin_lock_init(&sbi->s_next_gen_lock); 1025 1026 /* per fileystem reservation list head & lock */ 1027 spin_lock_init(&sbi->s_rsv_window_lock); 1028 sbi->s_rsv_window_root = RB_ROOT; 1029 /* 1030 * Add a single, static dummy reservation to the start of the 1031 * reservation window list --- it gives us a placeholder for 1032 * append-at-start-of-list which makes the allocation logic 1033 * _much_ simpler. 1034 */ 1035 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1036 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1037 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1038 sbi->s_rsv_window_head.rsv_goal_size = 0; 1039 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1040 1041 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1042 ext2_count_free_blocks(sb)); 1043 if (!err) { 1044 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1045 ext2_count_free_inodes(sb)); 1046 } 1047 if (!err) { 1048 err = percpu_counter_init(&sbi->s_dirs_counter, 1049 ext2_count_dirs(sb)); 1050 } 1051 if (err) { 1052 ext2_msg(sb, KERN_ERR, "error: insufficient memory"); 1053 goto failed_mount3; 1054 } 1055 /* 1056 * set up enough so that it can read an inode 1057 */ 1058 sb->s_op = &ext2_sops; 1059 sb->s_export_op = &ext2_export_ops; 1060 sb->s_xattr = ext2_xattr_handlers; 1061 root = ext2_iget(sb, EXT2_ROOT_INO); 1062 if (IS_ERR(root)) { 1063 ret = PTR_ERR(root); 1064 goto failed_mount3; 1065 } 1066 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1067 iput(root); 1068 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck"); 1069 goto failed_mount3; 1070 } 1071 1072 sb->s_root = d_alloc_root(root); 1073 if (!sb->s_root) { 1074 iput(root); 1075 ext2_msg(sb, KERN_ERR, "error: get root inode failed"); 1076 ret = -ENOMEM; 1077 goto failed_mount3; 1078 } 1079 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1080 ext2_msg(sb, KERN_WARNING, 1081 "warning: mounting ext3 filesystem as ext2"); 1082 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); 1083 return 0; 1084 1085 cantfind_ext2: 1086 if (!silent) 1087 ext2_msg(sb, KERN_ERR, 1088 "error: can't find an ext2 filesystem on dev %s.", 1089 sb->s_id); 1090 goto failed_mount; 1091 failed_mount3: 1092 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1093 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1094 percpu_counter_destroy(&sbi->s_dirs_counter); 1095 failed_mount2: 1096 for (i = 0; i < db_count; i++) 1097 brelse(sbi->s_group_desc[i]); 1098 failed_mount_group_desc: 1099 kfree(sbi->s_group_desc); 1100 kfree(sbi->s_debts); 1101 failed_mount: 1102 brelse(bh); 1103 failed_sbi: 1104 sb->s_fs_info = NULL; 1105 kfree(sbi->s_blockgroup_lock); 1106 kfree(sbi); 1107 return ret; 1108 } 1109 1110 static void ext2_clear_super_error(struct super_block *sb) 1111 { 1112 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1113 1114 if (buffer_write_io_error(sbh)) { 1115 /* 1116 * Oh, dear. A previous attempt to write the 1117 * superblock failed. This could happen because the 1118 * USB device was yanked out. Or it could happen to 1119 * be a transient write error and maybe the block will 1120 * be remapped. Nothing we can do but to retry the 1121 * write and hope for the best. 1122 */ 1123 printk(KERN_ERR "EXT2-fs: %s previous I/O error to " 1124 "superblock detected", sb->s_id); 1125 clear_buffer_write_io_error(sbh); 1126 set_buffer_uptodate(sbh); 1127 } 1128 } 1129 1130 static void ext2_commit_super (struct super_block * sb, 1131 struct ext2_super_block * es) 1132 { 1133 ext2_clear_super_error(sb); 1134 es->s_wtime = cpu_to_le32(get_seconds()); 1135 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1136 sb->s_dirt = 0; 1137 } 1138 1139 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) 1140 { 1141 ext2_clear_super_error(sb); 1142 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1143 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1144 es->s_wtime = cpu_to_le32(get_seconds()); 1145 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1146 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1147 sb->s_dirt = 0; 1148 } 1149 1150 /* 1151 * In the second extended file system, it is not necessary to 1152 * write the super block since we use a mapping of the 1153 * disk super block in a buffer. 1154 * 1155 * However, this function is still used to set the fs valid 1156 * flags to 0. We need to set this flag to 0 since the fs 1157 * may have been checked while mounted and e2fsck may have 1158 * set s_state to EXT2_VALID_FS after some corrections. 1159 */ 1160 1161 static int ext2_sync_fs(struct super_block *sb, int wait) 1162 { 1163 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1164 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh; 1165 1166 lock_kernel(); 1167 if (buffer_write_io_error(sbh)) { 1168 /* 1169 * Oh, dear. A previous attempt to write the 1170 * superblock failed. This could happen because the 1171 * USB device was yanked out. Or it could happen to 1172 * be a transient write error and maybe the block will 1173 * be remapped. Nothing we can do but to retry the 1174 * write and hope for the best. 1175 */ 1176 ext2_msg(sb, KERN_ERR, 1177 "previous I/O error to superblock detected\n"); 1178 clear_buffer_write_io_error(sbh); 1179 set_buffer_uptodate(sbh); 1180 } 1181 1182 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1183 ext2_debug("setting valid to 0\n"); 1184 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1185 es->s_free_blocks_count = 1186 cpu_to_le32(ext2_count_free_blocks(sb)); 1187 es->s_free_inodes_count = 1188 cpu_to_le32(ext2_count_free_inodes(sb)); 1189 es->s_mtime = cpu_to_le32(get_seconds()); 1190 ext2_sync_super(sb, es); 1191 } else { 1192 ext2_commit_super(sb, es); 1193 } 1194 sb->s_dirt = 0; 1195 unlock_kernel(); 1196 1197 return 0; 1198 } 1199 1200 1201 void ext2_write_super(struct super_block *sb) 1202 { 1203 if (!(sb->s_flags & MS_RDONLY)) 1204 ext2_sync_fs(sb, 1); 1205 else 1206 sb->s_dirt = 0; 1207 } 1208 1209 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1210 { 1211 struct ext2_sb_info * sbi = EXT2_SB(sb); 1212 struct ext2_super_block * es; 1213 unsigned long old_mount_opt = sbi->s_mount_opt; 1214 struct ext2_mount_options old_opts; 1215 unsigned long old_sb_flags; 1216 int err; 1217 1218 lock_kernel(); 1219 1220 /* Store the old options */ 1221 old_sb_flags = sb->s_flags; 1222 old_opts.s_mount_opt = sbi->s_mount_opt; 1223 old_opts.s_resuid = sbi->s_resuid; 1224 old_opts.s_resgid = sbi->s_resgid; 1225 1226 /* 1227 * Allow the "check" option to be passed as a remount option. 1228 */ 1229 if (!parse_options(data, sb)) { 1230 err = -EINVAL; 1231 goto restore_opts; 1232 } 1233 1234 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1235 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1236 1237 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 1238 EXT2_MOUNT_XIP if not */ 1239 1240 if ((ext2_use_xip(sb)) && (sb->s_blocksize != PAGE_SIZE)) { 1241 ext2_msg(sb, KERN_WARNING, 1242 "warning: unsupported blocksize for xip"); 1243 err = -EINVAL; 1244 goto restore_opts; 1245 } 1246 1247 es = sbi->s_es; 1248 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) != 1249 (old_mount_opt & EXT2_MOUNT_XIP)) && 1250 invalidate_inodes(sb)) { 1251 ext2_msg(sb, KERN_WARNING, "warning: refusing change of " 1252 "xip flag with busy inodes while remounting"); 1253 sbi->s_mount_opt &= ~EXT2_MOUNT_XIP; 1254 sbi->s_mount_opt |= old_mount_opt & EXT2_MOUNT_XIP; 1255 } 1256 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { 1257 unlock_kernel(); 1258 return 0; 1259 } 1260 if (*flags & MS_RDONLY) { 1261 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1262 !(sbi->s_mount_state & EXT2_VALID_FS)) { 1263 unlock_kernel(); 1264 return 0; 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 } else { 1273 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1274 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1275 if (ret) { 1276 ext2_msg(sb, KERN_WARNING, 1277 "warning: couldn't remount RDWR because of " 1278 "unsupported optional features (%x).", 1279 le32_to_cpu(ret)); 1280 err = -EROFS; 1281 goto restore_opts; 1282 } 1283 /* 1284 * Mounting a RDONLY partition read-write, so reread and 1285 * store the current valid flag. (It may have been changed 1286 * by e2fsck since we originally mounted the partition.) 1287 */ 1288 sbi->s_mount_state = le16_to_cpu(es->s_state); 1289 if (!ext2_setup_super (sb, es, 0)) 1290 sb->s_flags &= ~MS_RDONLY; 1291 } 1292 ext2_sync_super(sb, es); 1293 unlock_kernel(); 1294 return 0; 1295 restore_opts: 1296 sbi->s_mount_opt = old_opts.s_mount_opt; 1297 sbi->s_resuid = old_opts.s_resuid; 1298 sbi->s_resgid = old_opts.s_resgid; 1299 sb->s_flags = old_sb_flags; 1300 unlock_kernel(); 1301 return err; 1302 } 1303 1304 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1305 { 1306 struct super_block *sb = dentry->d_sb; 1307 struct ext2_sb_info *sbi = EXT2_SB(sb); 1308 struct ext2_super_block *es = sbi->s_es; 1309 u64 fsid; 1310 1311 if (test_opt (sb, MINIX_DF)) 1312 sbi->s_overhead_last = 0; 1313 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1314 unsigned long i, overhead = 0; 1315 smp_rmb(); 1316 1317 /* 1318 * Compute the overhead (FS structures). This is constant 1319 * for a given filesystem unless the number of block groups 1320 * changes so we cache the previous value until it does. 1321 */ 1322 1323 /* 1324 * All of the blocks before first_data_block are 1325 * overhead 1326 */ 1327 overhead = le32_to_cpu(es->s_first_data_block); 1328 1329 /* 1330 * Add the overhead attributed to the superblock and 1331 * block group descriptors. If the sparse superblocks 1332 * feature is turned on, then not all groups have this. 1333 */ 1334 for (i = 0; i < sbi->s_groups_count; i++) 1335 overhead += ext2_bg_has_super(sb, i) + 1336 ext2_bg_num_gdb(sb, i); 1337 1338 /* 1339 * Every block group has an inode bitmap, a block 1340 * bitmap, and an inode table. 1341 */ 1342 overhead += (sbi->s_groups_count * 1343 (2 + sbi->s_itb_per_group)); 1344 sbi->s_overhead_last = overhead; 1345 smp_wmb(); 1346 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1347 } 1348 1349 buf->f_type = EXT2_SUPER_MAGIC; 1350 buf->f_bsize = sb->s_blocksize; 1351 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1352 buf->f_bfree = ext2_count_free_blocks(sb); 1353 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1354 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1355 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1356 buf->f_bavail = 0; 1357 buf->f_files = le32_to_cpu(es->s_inodes_count); 1358 buf->f_ffree = ext2_count_free_inodes(sb); 1359 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1360 buf->f_namelen = EXT2_NAME_LEN; 1361 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1362 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1363 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1364 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1365 return 0; 1366 } 1367 1368 static int ext2_get_sb(struct file_system_type *fs_type, 1369 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 1370 { 1371 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt); 1372 } 1373 1374 #ifdef CONFIG_QUOTA 1375 1376 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1377 * acquiring the locks... As quota files are never truncated and quota code 1378 * itself serializes the operations (and noone else should touch the files) 1379 * we don't have to be afraid of races */ 1380 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1381 size_t len, loff_t off) 1382 { 1383 struct inode *inode = sb_dqopt(sb)->files[type]; 1384 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1385 int err = 0; 1386 int offset = off & (sb->s_blocksize - 1); 1387 int tocopy; 1388 size_t toread; 1389 struct buffer_head tmp_bh; 1390 struct buffer_head *bh; 1391 loff_t i_size = i_size_read(inode); 1392 1393 if (off > i_size) 1394 return 0; 1395 if (off+len > i_size) 1396 len = i_size-off; 1397 toread = len; 1398 while (toread > 0) { 1399 tocopy = sb->s_blocksize - offset < toread ? 1400 sb->s_blocksize - offset : toread; 1401 1402 tmp_bh.b_state = 0; 1403 tmp_bh.b_size = sb->s_blocksize; 1404 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1405 if (err < 0) 1406 return err; 1407 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1408 memset(data, 0, tocopy); 1409 else { 1410 bh = sb_bread(sb, tmp_bh.b_blocknr); 1411 if (!bh) 1412 return -EIO; 1413 memcpy(data, bh->b_data+offset, tocopy); 1414 brelse(bh); 1415 } 1416 offset = 0; 1417 toread -= tocopy; 1418 data += tocopy; 1419 blk++; 1420 } 1421 return len; 1422 } 1423 1424 /* Write to quotafile */ 1425 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1426 const char *data, size_t len, loff_t off) 1427 { 1428 struct inode *inode = sb_dqopt(sb)->files[type]; 1429 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1430 int err = 0; 1431 int offset = off & (sb->s_blocksize - 1); 1432 int tocopy; 1433 size_t towrite = len; 1434 struct buffer_head tmp_bh; 1435 struct buffer_head *bh; 1436 1437 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 1438 while (towrite > 0) { 1439 tocopy = sb->s_blocksize - offset < towrite ? 1440 sb->s_blocksize - offset : towrite; 1441 1442 tmp_bh.b_state = 0; 1443 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1444 if (err < 0) 1445 goto out; 1446 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1447 bh = sb_bread(sb, tmp_bh.b_blocknr); 1448 else 1449 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1450 if (!bh) { 1451 err = -EIO; 1452 goto out; 1453 } 1454 lock_buffer(bh); 1455 memcpy(bh->b_data+offset, data, tocopy); 1456 flush_dcache_page(bh->b_page); 1457 set_buffer_uptodate(bh); 1458 mark_buffer_dirty(bh); 1459 unlock_buffer(bh); 1460 brelse(bh); 1461 offset = 0; 1462 towrite -= tocopy; 1463 data += tocopy; 1464 blk++; 1465 } 1466 out: 1467 if (len == towrite) { 1468 mutex_unlock(&inode->i_mutex); 1469 return err; 1470 } 1471 if (inode->i_size < off+len-towrite) 1472 i_size_write(inode, off+len-towrite); 1473 inode->i_version++; 1474 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1475 mark_inode_dirty(inode); 1476 mutex_unlock(&inode->i_mutex); 1477 return len - towrite; 1478 } 1479 1480 #endif 1481 1482 static struct file_system_type ext2_fs_type = { 1483 .owner = THIS_MODULE, 1484 .name = "ext2", 1485 .get_sb = ext2_get_sb, 1486 .kill_sb = kill_block_super, 1487 .fs_flags = FS_REQUIRES_DEV, 1488 }; 1489 1490 static int __init init_ext2_fs(void) 1491 { 1492 int err = init_ext2_xattr(); 1493 if (err) 1494 return err; 1495 err = init_inodecache(); 1496 if (err) 1497 goto out1; 1498 err = register_filesystem(&ext2_fs_type); 1499 if (err) 1500 goto out; 1501 return 0; 1502 out: 1503 destroy_inodecache(); 1504 out1: 1505 exit_ext2_xattr(); 1506 return err; 1507 } 1508 1509 static void __exit exit_ext2_fs(void) 1510 { 1511 unregister_filesystem(&ext2_fs_type); 1512 destroy_inodecache(); 1513 exit_ext2_xattr(); 1514 } 1515 1516 module_init(init_ext2_fs) 1517 module_exit(exit_ext2_fs) 1518