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 <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); 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 45 void ext2_error (struct super_block * sb, const char * function, 46 const char * fmt, ...) 47 { 48 va_list args; 49 struct ext2_sb_info *sbi = EXT2_SB(sb); 50 struct ext2_super_block *es = sbi->s_es; 51 52 if (!(sb->s_flags & MS_RDONLY)) { 53 sbi->s_mount_state |= EXT2_ERROR_FS; 54 es->s_state = 55 cpu_to_le16(le16_to_cpu(es->s_state) | EXT2_ERROR_FS); 56 ext2_sync_super(sb, es); 57 } 58 59 va_start(args, fmt); 60 printk(KERN_CRIT "EXT2-fs error (device %s): %s: ",sb->s_id, function); 61 vprintk(fmt, args); 62 printk("\n"); 63 va_end(args); 64 65 if (test_opt(sb, ERRORS_PANIC)) 66 panic("EXT2-fs panic from previous error\n"); 67 if (test_opt(sb, ERRORS_RO)) { 68 printk("Remounting filesystem read-only\n"); 69 sb->s_flags |= MS_RDONLY; 70 } 71 } 72 73 void ext2_warning (struct super_block * sb, const char * function, 74 const char * fmt, ...) 75 { 76 va_list args; 77 78 va_start(args, fmt); 79 printk(KERN_WARNING "EXT2-fs warning (device %s): %s: ", 80 sb->s_id, function); 81 vprintk(fmt, args); 82 printk("\n"); 83 va_end(args); 84 } 85 86 void ext2_update_dynamic_rev(struct super_block *sb) 87 { 88 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 89 90 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) 91 return; 92 93 ext2_warning(sb, __FUNCTION__, 94 "updating to rev %d because of new feature flag, " 95 "running e2fsck is recommended", 96 EXT2_DYNAMIC_REV); 97 98 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); 99 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); 100 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); 101 /* leave es->s_feature_*compat flags alone */ 102 /* es->s_uuid will be set by e2fsck if empty */ 103 104 /* 105 * The rest of the superblock fields should be zero, and if not it 106 * means they are likely already in use, so leave them alone. We 107 * can leave it up to e2fsck to clean up any inconsistencies there. 108 */ 109 } 110 111 static void ext2_put_super (struct super_block * sb) 112 { 113 int db_count; 114 int i; 115 struct ext2_sb_info *sbi = EXT2_SB(sb); 116 117 ext2_xattr_put_super(sb); 118 if (!(sb->s_flags & MS_RDONLY)) { 119 struct ext2_super_block *es = sbi->s_es; 120 121 es->s_state = cpu_to_le16(sbi->s_mount_state); 122 ext2_sync_super(sb, es); 123 } 124 db_count = sbi->s_gdb_count; 125 for (i = 0; i < db_count; i++) 126 if (sbi->s_group_desc[i]) 127 brelse (sbi->s_group_desc[i]); 128 kfree(sbi->s_group_desc); 129 kfree(sbi->s_debts); 130 percpu_counter_destroy(&sbi->s_freeblocks_counter); 131 percpu_counter_destroy(&sbi->s_freeinodes_counter); 132 percpu_counter_destroy(&sbi->s_dirs_counter); 133 brelse (sbi->s_sbh); 134 sb->s_fs_info = NULL; 135 kfree(sbi); 136 137 return; 138 } 139 140 static struct kmem_cache * ext2_inode_cachep; 141 142 static struct inode *ext2_alloc_inode(struct super_block *sb) 143 { 144 struct ext2_inode_info *ei; 145 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL); 146 if (!ei) 147 return NULL; 148 #ifdef CONFIG_EXT2_FS_POSIX_ACL 149 ei->i_acl = EXT2_ACL_NOT_CACHED; 150 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 151 #endif 152 ei->i_block_alloc_info = NULL; 153 ei->vfs_inode.i_version = 1; 154 return &ei->vfs_inode; 155 } 156 157 static void ext2_destroy_inode(struct inode *inode) 158 { 159 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 160 } 161 162 static void init_once(struct kmem_cache * cachep, void *foo) 163 { 164 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 165 166 rwlock_init(&ei->i_meta_lock); 167 #ifdef CONFIG_EXT2_FS_XATTR 168 init_rwsem(&ei->xattr_sem); 169 #endif 170 mutex_init(&ei->truncate_mutex); 171 inode_init_once(&ei->vfs_inode); 172 } 173 174 static int init_inodecache(void) 175 { 176 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 177 sizeof(struct ext2_inode_info), 178 0, (SLAB_RECLAIM_ACCOUNT| 179 SLAB_MEM_SPREAD), 180 init_once); 181 if (ext2_inode_cachep == NULL) 182 return -ENOMEM; 183 return 0; 184 } 185 186 static void destroy_inodecache(void) 187 { 188 kmem_cache_destroy(ext2_inode_cachep); 189 } 190 191 static void ext2_clear_inode(struct inode *inode) 192 { 193 struct ext2_block_alloc_info *rsv = EXT2_I(inode)->i_block_alloc_info; 194 #ifdef CONFIG_EXT2_FS_POSIX_ACL 195 struct ext2_inode_info *ei = EXT2_I(inode); 196 197 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) { 198 posix_acl_release(ei->i_acl); 199 ei->i_acl = EXT2_ACL_NOT_CACHED; 200 } 201 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) { 202 posix_acl_release(ei->i_default_acl); 203 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 204 } 205 #endif 206 ext2_discard_reservation(inode); 207 EXT2_I(inode)->i_block_alloc_info = NULL; 208 if (unlikely(rsv)) 209 kfree(rsv); 210 } 211 212 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs) 213 { 214 struct super_block *sb = vfs->mnt_sb; 215 struct ext2_sb_info *sbi = EXT2_SB(sb); 216 struct ext2_super_block *es = sbi->s_es; 217 unsigned long def_mount_opts; 218 219 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 220 221 if (sbi->s_sb_block != 1) 222 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 223 if (test_opt(sb, MINIX_DF)) 224 seq_puts(seq, ",minixdf"); 225 if (test_opt(sb, GRPID)) 226 seq_puts(seq, ",grpid"); 227 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 228 seq_puts(seq, ",nogrpid"); 229 if (sbi->s_resuid != EXT2_DEF_RESUID || 230 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 231 seq_printf(seq, ",resuid=%u", sbi->s_resuid); 232 } 233 if (sbi->s_resgid != EXT2_DEF_RESGID || 234 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 235 seq_printf(seq, ",resgid=%u", sbi->s_resgid); 236 } 237 if (test_opt(sb, ERRORS_CONT)) { 238 int def_errors = le16_to_cpu(es->s_errors); 239 240 if (def_errors == EXT2_ERRORS_PANIC || 241 def_errors == EXT2_ERRORS_RO) { 242 seq_puts(seq, ",errors=continue"); 243 } 244 } 245 if (test_opt(sb, ERRORS_RO)) 246 seq_puts(seq, ",errors=remount-ro"); 247 if (test_opt(sb, ERRORS_PANIC)) 248 seq_puts(seq, ",errors=panic"); 249 if (test_opt(sb, NO_UID32)) 250 seq_puts(seq, ",nouid32"); 251 if (test_opt(sb, DEBUG)) 252 seq_puts(seq, ",debug"); 253 if (test_opt(sb, OLDALLOC)) 254 seq_puts(seq, ",oldalloc"); 255 256 #ifdef CONFIG_EXT2_FS_XATTR 257 if (test_opt(sb, XATTR_USER)) 258 seq_puts(seq, ",user_xattr"); 259 if (!test_opt(sb, XATTR_USER) && 260 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 261 seq_puts(seq, ",nouser_xattr"); 262 } 263 #endif 264 265 #ifdef CONFIG_EXT2_FS_POSIX_ACL 266 if (test_opt(sb, POSIX_ACL)) 267 seq_puts(seq, ",acl"); 268 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 269 seq_puts(seq, ",noacl"); 270 #endif 271 272 if (test_opt(sb, NOBH)) 273 seq_puts(seq, ",nobh"); 274 275 #if defined(CONFIG_QUOTA) 276 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 277 seq_puts(seq, ",usrquota"); 278 279 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 280 seq_puts(seq, ",grpquota"); 281 #endif 282 283 #if defined(CONFIG_EXT2_FS_XIP) 284 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 285 seq_puts(seq, ",xip"); 286 #endif 287 288 return 0; 289 } 290 291 #ifdef CONFIG_QUOTA 292 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 293 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 294 #endif 295 296 static const struct super_operations ext2_sops = { 297 .alloc_inode = ext2_alloc_inode, 298 .destroy_inode = ext2_destroy_inode, 299 .read_inode = ext2_read_inode, 300 .write_inode = ext2_write_inode, 301 .delete_inode = ext2_delete_inode, 302 .put_super = ext2_put_super, 303 .write_super = ext2_write_super, 304 .statfs = ext2_statfs, 305 .remount_fs = ext2_remount, 306 .clear_inode = ext2_clear_inode, 307 .show_options = ext2_show_options, 308 #ifdef CONFIG_QUOTA 309 .quota_read = ext2_quota_read, 310 .quota_write = ext2_quota_write, 311 #endif 312 }; 313 314 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp) 315 { 316 __u32 *objp = vobjp; 317 unsigned long ino = objp[0]; 318 __u32 generation = objp[1]; 319 struct inode *inode; 320 struct dentry *result; 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 /* iget isn't really right if the inode is currently unallocated!! 328 * ext2_read_inode currently does appropriate checks, but 329 * it might be "neater" to call ext2_get_inode first and check 330 * if the inode is valid..... 331 */ 332 inode = iget(sb, ino); 333 if (inode == NULL) 334 return ERR_PTR(-ENOMEM); 335 if (is_bad_inode(inode) || 336 (generation && inode->i_generation != generation)) { 337 /* we didn't find the right inode.. */ 338 iput(inode); 339 return ERR_PTR(-ESTALE); 340 } 341 /* now to find a dentry. 342 * If possible, get a well-connected one 343 */ 344 result = d_alloc_anon(inode); 345 if (!result) { 346 iput(inode); 347 return ERR_PTR(-ENOMEM); 348 } 349 return result; 350 } 351 352 /* Yes, most of these are left as NULL!! 353 * A NULL value implies the default, which works with ext2-like file 354 * systems, but can be improved upon. 355 * Currently only get_parent is required. 356 */ 357 static struct export_operations ext2_export_ops = { 358 .get_parent = ext2_get_parent, 359 .get_dentry = ext2_get_dentry, 360 }; 361 362 static unsigned long get_sb_block(void **data) 363 { 364 unsigned long sb_block; 365 char *options = (char *) *data; 366 367 if (!options || strncmp(options, "sb=", 3) != 0) 368 return 1; /* Default location */ 369 options += 3; 370 sb_block = simple_strtoul(options, &options, 0); 371 if (*options && *options != ',') { 372 printk("EXT2-fs: Invalid sb specification: %s\n", 373 (char *) *data); 374 return 1; 375 } 376 if (*options == ',') 377 options++; 378 *data = (void *) options; 379 return sb_block; 380 } 381 382 enum { 383 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 384 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 385 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 386 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 387 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, 388 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 389 }; 390 391 static match_table_t tokens = { 392 {Opt_bsd_df, "bsddf"}, 393 {Opt_minix_df, "minixdf"}, 394 {Opt_grpid, "grpid"}, 395 {Opt_grpid, "bsdgroups"}, 396 {Opt_nogrpid, "nogrpid"}, 397 {Opt_nogrpid, "sysvgroups"}, 398 {Opt_resgid, "resgid=%u"}, 399 {Opt_resuid, "resuid=%u"}, 400 {Opt_sb, "sb=%u"}, 401 {Opt_err_cont, "errors=continue"}, 402 {Opt_err_panic, "errors=panic"}, 403 {Opt_err_ro, "errors=remount-ro"}, 404 {Opt_nouid32, "nouid32"}, 405 {Opt_nocheck, "check=none"}, 406 {Opt_nocheck, "nocheck"}, 407 {Opt_debug, "debug"}, 408 {Opt_oldalloc, "oldalloc"}, 409 {Opt_orlov, "orlov"}, 410 {Opt_nobh, "nobh"}, 411 {Opt_user_xattr, "user_xattr"}, 412 {Opt_nouser_xattr, "nouser_xattr"}, 413 {Opt_acl, "acl"}, 414 {Opt_noacl, "noacl"}, 415 {Opt_xip, "xip"}, 416 {Opt_grpquota, "grpquota"}, 417 {Opt_ignore, "noquota"}, 418 {Opt_quota, "quota"}, 419 {Opt_usrquota, "usrquota"}, 420 {Opt_reservation, "reservation"}, 421 {Opt_noreservation, "noreservation"}, 422 {Opt_err, NULL} 423 }; 424 425 static int parse_options (char * options, 426 struct ext2_sb_info *sbi) 427 { 428 char * p; 429 substring_t args[MAX_OPT_ARGS]; 430 int option; 431 432 if (!options) 433 return 1; 434 435 while ((p = strsep (&options, ",")) != NULL) { 436 int token; 437 if (!*p) 438 continue; 439 440 token = match_token(p, tokens, args); 441 switch (token) { 442 case Opt_bsd_df: 443 clear_opt (sbi->s_mount_opt, MINIX_DF); 444 break; 445 case Opt_minix_df: 446 set_opt (sbi->s_mount_opt, MINIX_DF); 447 break; 448 case Opt_grpid: 449 set_opt (sbi->s_mount_opt, GRPID); 450 break; 451 case Opt_nogrpid: 452 clear_opt (sbi->s_mount_opt, GRPID); 453 break; 454 case Opt_resuid: 455 if (match_int(&args[0], &option)) 456 return 0; 457 sbi->s_resuid = option; 458 break; 459 case Opt_resgid: 460 if (match_int(&args[0], &option)) 461 return 0; 462 sbi->s_resgid = option; 463 break; 464 case Opt_sb: 465 /* handled by get_sb_block() instead of here */ 466 /* *sb_block = match_int(&args[0]); */ 467 break; 468 case Opt_err_panic: 469 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 470 clear_opt (sbi->s_mount_opt, ERRORS_RO); 471 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 472 break; 473 case Opt_err_ro: 474 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 475 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 476 set_opt (sbi->s_mount_opt, ERRORS_RO); 477 break; 478 case Opt_err_cont: 479 clear_opt (sbi->s_mount_opt, ERRORS_RO); 480 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 481 set_opt (sbi->s_mount_opt, ERRORS_CONT); 482 break; 483 case Opt_nouid32: 484 set_opt (sbi->s_mount_opt, NO_UID32); 485 break; 486 case Opt_nocheck: 487 clear_opt (sbi->s_mount_opt, CHECK); 488 break; 489 case Opt_debug: 490 set_opt (sbi->s_mount_opt, DEBUG); 491 break; 492 case Opt_oldalloc: 493 set_opt (sbi->s_mount_opt, OLDALLOC); 494 break; 495 case Opt_orlov: 496 clear_opt (sbi->s_mount_opt, OLDALLOC); 497 break; 498 case Opt_nobh: 499 set_opt (sbi->s_mount_opt, NOBH); 500 break; 501 #ifdef CONFIG_EXT2_FS_XATTR 502 case Opt_user_xattr: 503 set_opt (sbi->s_mount_opt, XATTR_USER); 504 break; 505 case Opt_nouser_xattr: 506 clear_opt (sbi->s_mount_opt, XATTR_USER); 507 break; 508 #else 509 case Opt_user_xattr: 510 case Opt_nouser_xattr: 511 printk("EXT2 (no)user_xattr options not supported\n"); 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 printk("EXT2 (no)acl options not supported\n"); 525 break; 526 #endif 527 case Opt_xip: 528 #ifdef CONFIG_EXT2_FS_XIP 529 set_opt (sbi->s_mount_opt, XIP); 530 #else 531 printk("EXT2 xip option not supported\n"); 532 #endif 533 break; 534 535 #if defined(CONFIG_QUOTA) 536 case Opt_quota: 537 case Opt_usrquota: 538 set_opt(sbi->s_mount_opt, USRQUOTA); 539 break; 540 541 case Opt_grpquota: 542 set_opt(sbi->s_mount_opt, GRPQUOTA); 543 break; 544 #else 545 case Opt_quota: 546 case Opt_usrquota: 547 case Opt_grpquota: 548 printk(KERN_ERR 549 "EXT2-fs: quota operations not supported.\n"); 550 551 break; 552 #endif 553 554 case Opt_reservation: 555 set_opt(sbi->s_mount_opt, RESERVATION); 556 printk("reservations ON\n"); 557 break; 558 case Opt_noreservation: 559 clear_opt(sbi->s_mount_opt, RESERVATION); 560 printk("reservations OFF\n"); 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 printk ("EXT2-fs warning: revision level too high, " 580 "forcing read-only mode\n"); 581 res = MS_RDONLY; 582 } 583 if (read_only) 584 return res; 585 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 586 printk ("EXT2-fs warning: mounting unchecked fs, " 587 "running e2fsck is recommended\n"); 588 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 589 printk ("EXT2-fs warning: mounting fs with errors, " 590 "running e2fsck is recommended\n"); 591 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 592 le16_to_cpu(es->s_mnt_count) >= 593 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 594 printk ("EXT2-fs warning: maximal mount count reached, " 595 "running e2fsck is recommended\n"); 596 else if (le32_to_cpu(es->s_checkinterval) && 597 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds())) 598 printk ("EXT2-fs warning: checktime reached, " 599 "running e2fsck is recommended\n"); 600 if (!le16_to_cpu(es->s_max_mnt_count)) 601 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 602 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1); 603 ext2_write_super(sb); 604 if (test_opt (sb, DEBUG)) 605 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, " 606 "bpg=%lu, ipg=%lu, mo=%04lx]\n", 607 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 608 sbi->s_frag_size, 609 sbi->s_groups_count, 610 EXT2_BLOCKS_PER_GROUP(sb), 611 EXT2_INODES_PER_GROUP(sb), 612 sbi->s_mount_opt); 613 return res; 614 } 615 616 static int ext2_check_descriptors (struct super_block * sb) 617 { 618 int i; 619 int desc_block = 0; 620 struct ext2_sb_info *sbi = EXT2_SB(sb); 621 unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block); 622 unsigned long last_block; 623 struct ext2_group_desc * gdp = NULL; 624 625 ext2_debug ("Checking group descriptors"); 626 627 for (i = 0; i < sbi->s_groups_count; i++) 628 { 629 if (i == sbi->s_groups_count - 1) 630 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 631 else 632 last_block = first_block + 633 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 634 635 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0) 636 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data; 637 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 638 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 639 { 640 ext2_error (sb, "ext2_check_descriptors", 641 "Block bitmap for group %d" 642 " not in group (block %lu)!", 643 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 644 return 0; 645 } 646 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 647 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 648 { 649 ext2_error (sb, "ext2_check_descriptors", 650 "Inode bitmap for group %d" 651 " not in group (block %lu)!", 652 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 653 return 0; 654 } 655 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 656 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 657 last_block) 658 { 659 ext2_error (sb, "ext2_check_descriptors", 660 "Inode table for group %d" 661 " not in group (block %lu)!", 662 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 663 return 0; 664 } 665 first_block += EXT2_BLOCKS_PER_GROUP(sb); 666 gdp++; 667 } 668 return 1; 669 } 670 671 /* 672 * Maximal file size. There is a direct, and {,double-,triple-}indirect 673 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 674 * We need to be 1 filesystem block less than the 2^32 sector limit. 675 */ 676 static loff_t ext2_max_size(int bits) 677 { 678 loff_t res = EXT2_NDIR_BLOCKS; 679 /* This constant is calculated to be the largest file size for a 680 * dense, 4k-blocksize file such that the total number of 681 * sectors in the file, including data and all indirect blocks, 682 * does not exceed 2^32. */ 683 const loff_t upper_limit = 0x1ff7fffd000LL; 684 685 res += 1LL << (bits-2); 686 res += 1LL << (2*(bits-2)); 687 res += 1LL << (3*(bits-2)); 688 res <<= bits; 689 if (res > upper_limit) 690 res = upper_limit; 691 return res; 692 } 693 694 static unsigned long descriptor_loc(struct super_block *sb, 695 unsigned long logic_sb_block, 696 int nr) 697 { 698 struct ext2_sb_info *sbi = EXT2_SB(sb); 699 unsigned long bg, first_data_block, first_meta_bg; 700 int has_super = 0; 701 702 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block); 703 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 704 705 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 706 nr < first_meta_bg) 707 return (logic_sb_block + nr + 1); 708 bg = sbi->s_desc_per_block * nr; 709 if (ext2_bg_has_super(sb, bg)) 710 has_super = 1; 711 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group)); 712 } 713 714 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 715 { 716 struct buffer_head * bh; 717 struct ext2_sb_info * sbi; 718 struct ext2_super_block * es; 719 struct inode *root; 720 unsigned long block; 721 unsigned long sb_block = get_sb_block(&data); 722 unsigned long logic_sb_block; 723 unsigned long offset = 0; 724 unsigned long def_mount_opts; 725 int blocksize = BLOCK_SIZE; 726 int db_count; 727 int i, j; 728 __le32 features; 729 int err; 730 731 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 732 if (!sbi) 733 return -ENOMEM; 734 sb->s_fs_info = sbi; 735 sbi->s_sb_block = sb_block; 736 737 /* 738 * See what the current blocksize for the device is, and 739 * use that as the blocksize. Otherwise (or if the blocksize 740 * is smaller than the default) use the default. 741 * This is important for devices that have a hardware 742 * sectorsize that is larger than the default. 743 */ 744 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 745 if (!blocksize) { 746 printk ("EXT2-fs: unable to set blocksize\n"); 747 goto failed_sbi; 748 } 749 750 /* 751 * If the superblock doesn't start on a hardware sector boundary, 752 * calculate the offset. 753 */ 754 if (blocksize != BLOCK_SIZE) { 755 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 756 offset = (sb_block*BLOCK_SIZE) % blocksize; 757 } else { 758 logic_sb_block = sb_block; 759 } 760 761 if (!(bh = sb_bread(sb, logic_sb_block))) { 762 printk ("EXT2-fs: unable to read superblock\n"); 763 goto failed_sbi; 764 } 765 /* 766 * Note: s_es must be initialized as soon as possible because 767 * some ext2 macro-instructions depend on its value 768 */ 769 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 770 sbi->s_es = es; 771 sb->s_magic = le16_to_cpu(es->s_magic); 772 773 if (sb->s_magic != EXT2_SUPER_MAGIC) 774 goto cantfind_ext2; 775 776 /* Set defaults before we parse the mount options */ 777 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 778 if (def_mount_opts & EXT2_DEFM_DEBUG) 779 set_opt(sbi->s_mount_opt, DEBUG); 780 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 781 set_opt(sbi->s_mount_opt, GRPID); 782 if (def_mount_opts & EXT2_DEFM_UID16) 783 set_opt(sbi->s_mount_opt, NO_UID32); 784 #ifdef CONFIG_EXT2_FS_XATTR 785 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 786 set_opt(sbi->s_mount_opt, XATTR_USER); 787 #endif 788 #ifdef CONFIG_EXT2_FS_POSIX_ACL 789 if (def_mount_opts & EXT2_DEFM_ACL) 790 set_opt(sbi->s_mount_opt, POSIX_ACL); 791 #endif 792 793 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 794 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 795 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO) 796 set_opt(sbi->s_mount_opt, ERRORS_RO); 797 else 798 set_opt(sbi->s_mount_opt, ERRORS_CONT); 799 800 sbi->s_resuid = le16_to_cpu(es->s_def_resuid); 801 sbi->s_resgid = le16_to_cpu(es->s_def_resgid); 802 803 set_opt(sbi->s_mount_opt, RESERVATION); 804 805 if (!parse_options ((char *) data, sbi)) 806 goto failed_mount; 807 808 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 809 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 810 MS_POSIXACL : 0); 811 812 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 813 EXT2_MOUNT_XIP if not */ 814 815 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 816 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 817 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 818 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 819 printk("EXT2-fs warning: feature flags set on rev 0 fs, " 820 "running e2fsck is recommended\n"); 821 /* 822 * Check feature flags regardless of the revision level, since we 823 * previously didn't change the revision level when setting the flags, 824 * so there is a chance incompat flags are set on a rev 0 filesystem. 825 */ 826 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 827 if (features) { 828 printk("EXT2-fs: %s: couldn't mount because of " 829 "unsupported optional features (%x).\n", 830 sb->s_id, le32_to_cpu(features)); 831 goto failed_mount; 832 } 833 if (!(sb->s_flags & MS_RDONLY) && 834 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 835 printk("EXT2-fs: %s: couldn't mount RDWR because of " 836 "unsupported optional features (%x).\n", 837 sb->s_id, le32_to_cpu(features)); 838 goto failed_mount; 839 } 840 841 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 842 843 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) || 844 (sb->s_blocksize != blocksize))) { 845 if (!silent) 846 printk("XIP: Unsupported blocksize\n"); 847 goto failed_mount; 848 } 849 850 /* If the blocksize doesn't match, re-read the thing.. */ 851 if (sb->s_blocksize != blocksize) { 852 brelse(bh); 853 854 if (!sb_set_blocksize(sb, blocksize)) { 855 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); 856 goto failed_sbi; 857 } 858 859 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 860 offset = (sb_block*BLOCK_SIZE) % blocksize; 861 bh = sb_bread(sb, logic_sb_block); 862 if(!bh) { 863 printk("EXT2-fs: Couldn't read superblock on " 864 "2nd try.\n"); 865 goto failed_sbi; 866 } 867 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 868 sbi->s_es = es; 869 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 870 printk ("EXT2-fs: Magic mismatch, very weird !\n"); 871 goto failed_mount; 872 } 873 } 874 875 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 876 877 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 878 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 879 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 880 } else { 881 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 882 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 883 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 884 !is_power_of_2(sbi->s_inode_size) || 885 (sbi->s_inode_size > blocksize)) { 886 printk ("EXT2-fs: unsupported inode size: %d\n", 887 sbi->s_inode_size); 888 goto failed_mount; 889 } 890 } 891 892 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 893 le32_to_cpu(es->s_log_frag_size); 894 if (sbi->s_frag_size == 0) 895 goto cantfind_ext2; 896 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 897 898 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 899 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 900 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 901 902 if (EXT2_INODE_SIZE(sb) == 0) 903 goto cantfind_ext2; 904 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 905 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 906 goto cantfind_ext2; 907 sbi->s_itb_per_group = sbi->s_inodes_per_group / 908 sbi->s_inodes_per_block; 909 sbi->s_desc_per_block = sb->s_blocksize / 910 sizeof (struct ext2_group_desc); 911 sbi->s_sbh = bh; 912 sbi->s_mount_state = le16_to_cpu(es->s_state); 913 sbi->s_addr_per_block_bits = 914 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 915 sbi->s_desc_per_block_bits = 916 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 917 918 if (sb->s_magic != EXT2_SUPER_MAGIC) 919 goto cantfind_ext2; 920 921 if (sb->s_blocksize != bh->b_size) { 922 if (!silent) 923 printk ("VFS: Unsupported blocksize on dev " 924 "%s.\n", sb->s_id); 925 goto failed_mount; 926 } 927 928 if (sb->s_blocksize != sbi->s_frag_size) { 929 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n", 930 sbi->s_frag_size, sb->s_blocksize); 931 goto failed_mount; 932 } 933 934 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 935 printk ("EXT2-fs: #blocks per group too big: %lu\n", 936 sbi->s_blocks_per_group); 937 goto failed_mount; 938 } 939 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 940 printk ("EXT2-fs: #fragments per group too big: %lu\n", 941 sbi->s_frags_per_group); 942 goto failed_mount; 943 } 944 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 945 printk ("EXT2-fs: #inodes per group too big: %lu\n", 946 sbi->s_inodes_per_group); 947 goto failed_mount; 948 } 949 950 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 951 goto cantfind_ext2; 952 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 953 le32_to_cpu(es->s_first_data_block) - 1) 954 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 955 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 956 EXT2_DESC_PER_BLOCK(sb); 957 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 958 if (sbi->s_group_desc == NULL) { 959 printk ("EXT2-fs: not enough memory\n"); 960 goto failed_mount; 961 } 962 bgl_lock_init(&sbi->s_blockgroup_lock); 963 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL); 964 if (!sbi->s_debts) { 965 printk ("EXT2-fs: not enough memory\n"); 966 goto failed_mount_group_desc; 967 } 968 for (i = 0; i < db_count; i++) { 969 block = descriptor_loc(sb, logic_sb_block, i); 970 sbi->s_group_desc[i] = sb_bread(sb, block); 971 if (!sbi->s_group_desc[i]) { 972 for (j = 0; j < i; j++) 973 brelse (sbi->s_group_desc[j]); 974 printk ("EXT2-fs: unable to read group descriptors\n"); 975 goto failed_mount_group_desc; 976 } 977 } 978 if (!ext2_check_descriptors (sb)) { 979 printk ("EXT2-fs: group descriptors corrupted!\n"); 980 goto failed_mount2; 981 } 982 sbi->s_gdb_count = db_count; 983 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 984 spin_lock_init(&sbi->s_next_gen_lock); 985 986 /* per fileystem reservation list head & lock */ 987 spin_lock_init(&sbi->s_rsv_window_lock); 988 sbi->s_rsv_window_root = RB_ROOT; 989 /* 990 * Add a single, static dummy reservation to the start of the 991 * reservation window list --- it gives us a placeholder for 992 * append-at-start-of-list which makes the allocation logic 993 * _much_ simpler. 994 */ 995 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 996 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 997 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 998 sbi->s_rsv_window_head.rsv_goal_size = 0; 999 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1000 1001 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1002 ext2_count_free_blocks(sb)); 1003 if (!err) { 1004 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1005 ext2_count_free_inodes(sb)); 1006 } 1007 if (!err) { 1008 err = percpu_counter_init(&sbi->s_dirs_counter, 1009 ext2_count_dirs(sb)); 1010 } 1011 if (err) { 1012 printk(KERN_ERR "EXT2-fs: insufficient memory\n"); 1013 goto failed_mount3; 1014 } 1015 /* 1016 * set up enough so that it can read an inode 1017 */ 1018 sb->s_op = &ext2_sops; 1019 sb->s_export_op = &ext2_export_ops; 1020 sb->s_xattr = ext2_xattr_handlers; 1021 root = iget(sb, EXT2_ROOT_INO); 1022 sb->s_root = d_alloc_root(root); 1023 if (!sb->s_root) { 1024 iput(root); 1025 printk(KERN_ERR "EXT2-fs: get root inode failed\n"); 1026 goto failed_mount3; 1027 } 1028 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1029 dput(sb->s_root); 1030 sb->s_root = NULL; 1031 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n"); 1032 goto failed_mount3; 1033 } 1034 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1035 ext2_warning(sb, __FUNCTION__, 1036 "mounting ext3 filesystem as ext2"); 1037 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); 1038 return 0; 1039 1040 cantfind_ext2: 1041 if (!silent) 1042 printk("VFS: Can't find an ext2 filesystem on dev %s.\n", 1043 sb->s_id); 1044 goto failed_mount; 1045 failed_mount3: 1046 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1047 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1048 percpu_counter_destroy(&sbi->s_dirs_counter); 1049 failed_mount2: 1050 for (i = 0; i < db_count; i++) 1051 brelse(sbi->s_group_desc[i]); 1052 failed_mount_group_desc: 1053 kfree(sbi->s_group_desc); 1054 kfree(sbi->s_debts); 1055 failed_mount: 1056 brelse(bh); 1057 failed_sbi: 1058 sb->s_fs_info = NULL; 1059 kfree(sbi); 1060 return -EINVAL; 1061 } 1062 1063 static void ext2_commit_super (struct super_block * sb, 1064 struct ext2_super_block * es) 1065 { 1066 es->s_wtime = cpu_to_le32(get_seconds()); 1067 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1068 sb->s_dirt = 0; 1069 } 1070 1071 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) 1072 { 1073 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1074 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1075 es->s_wtime = cpu_to_le32(get_seconds()); 1076 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1077 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1078 sb->s_dirt = 0; 1079 } 1080 1081 /* 1082 * In the second extended file system, it is not necessary to 1083 * write the super block since we use a mapping of the 1084 * disk super block in a buffer. 1085 * 1086 * However, this function is still used to set the fs valid 1087 * flags to 0. We need to set this flag to 0 since the fs 1088 * may have been checked while mounted and e2fsck may have 1089 * set s_state to EXT2_VALID_FS after some corrections. 1090 */ 1091 1092 void ext2_write_super (struct super_block * sb) 1093 { 1094 struct ext2_super_block * es; 1095 lock_kernel(); 1096 if (!(sb->s_flags & MS_RDONLY)) { 1097 es = EXT2_SB(sb)->s_es; 1098 1099 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) { 1100 ext2_debug ("setting valid to 0\n"); 1101 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & 1102 ~EXT2_VALID_FS); 1103 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1104 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1105 es->s_mtime = cpu_to_le32(get_seconds()); 1106 ext2_sync_super(sb, es); 1107 } else 1108 ext2_commit_super (sb, es); 1109 } 1110 sb->s_dirt = 0; 1111 unlock_kernel(); 1112 } 1113 1114 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1115 { 1116 struct ext2_sb_info * sbi = EXT2_SB(sb); 1117 struct ext2_super_block * es; 1118 unsigned long old_mount_opt = sbi->s_mount_opt; 1119 struct ext2_mount_options old_opts; 1120 unsigned long old_sb_flags; 1121 int err; 1122 1123 /* Store the old options */ 1124 old_sb_flags = sb->s_flags; 1125 old_opts.s_mount_opt = sbi->s_mount_opt; 1126 old_opts.s_resuid = sbi->s_resuid; 1127 old_opts.s_resgid = sbi->s_resgid; 1128 1129 /* 1130 * Allow the "check" option to be passed as a remount option. 1131 */ 1132 if (!parse_options (data, sbi)) { 1133 err = -EINVAL; 1134 goto restore_opts; 1135 } 1136 1137 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1138 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1139 1140 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 1141 EXT2_MOUNT_XIP if not */ 1142 1143 if ((ext2_use_xip(sb)) && (sb->s_blocksize != PAGE_SIZE)) { 1144 printk("XIP: Unsupported blocksize\n"); 1145 err = -EINVAL; 1146 goto restore_opts; 1147 } 1148 1149 es = sbi->s_es; 1150 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) != 1151 (old_mount_opt & EXT2_MOUNT_XIP)) && 1152 invalidate_inodes(sb)) 1153 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\ 1154 "xip remain in cache (no functional problem)"); 1155 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 1156 return 0; 1157 if (*flags & MS_RDONLY) { 1158 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1159 !(sbi->s_mount_state & EXT2_VALID_FS)) 1160 return 0; 1161 /* 1162 * OK, we are remounting a valid rw partition rdonly, so set 1163 * the rdonly flag and then mark the partition as valid again. 1164 */ 1165 es->s_state = cpu_to_le16(sbi->s_mount_state); 1166 es->s_mtime = cpu_to_le32(get_seconds()); 1167 } else { 1168 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1169 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1170 if (ret) { 1171 printk("EXT2-fs: %s: couldn't remount RDWR because of " 1172 "unsupported optional features (%x).\n", 1173 sb->s_id, le32_to_cpu(ret)); 1174 err = -EROFS; 1175 goto restore_opts; 1176 } 1177 /* 1178 * Mounting a RDONLY partition read-write, so reread and 1179 * store the current valid flag. (It may have been changed 1180 * by e2fsck since we originally mounted the partition.) 1181 */ 1182 sbi->s_mount_state = le16_to_cpu(es->s_state); 1183 if (!ext2_setup_super (sb, es, 0)) 1184 sb->s_flags &= ~MS_RDONLY; 1185 } 1186 ext2_sync_super(sb, es); 1187 return 0; 1188 restore_opts: 1189 sbi->s_mount_opt = old_opts.s_mount_opt; 1190 sbi->s_resuid = old_opts.s_resuid; 1191 sbi->s_resgid = old_opts.s_resgid; 1192 sb->s_flags = old_sb_flags; 1193 return err; 1194 } 1195 1196 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1197 { 1198 struct super_block *sb = dentry->d_sb; 1199 struct ext2_sb_info *sbi = EXT2_SB(sb); 1200 struct ext2_super_block *es = sbi->s_es; 1201 u64 fsid; 1202 1203 if (test_opt (sb, MINIX_DF)) 1204 sbi->s_overhead_last = 0; 1205 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1206 unsigned long i, overhead = 0; 1207 smp_rmb(); 1208 1209 /* 1210 * Compute the overhead (FS structures). This is constant 1211 * for a given filesystem unless the number of block groups 1212 * changes so we cache the previous value until it does. 1213 */ 1214 1215 /* 1216 * All of the blocks before first_data_block are 1217 * overhead 1218 */ 1219 overhead = le32_to_cpu(es->s_first_data_block); 1220 1221 /* 1222 * Add the overhead attributed to the superblock and 1223 * block group descriptors. If the sparse superblocks 1224 * feature is turned on, then not all groups have this. 1225 */ 1226 for (i = 0; i < sbi->s_groups_count; i++) 1227 overhead += ext2_bg_has_super(sb, i) + 1228 ext2_bg_num_gdb(sb, i); 1229 1230 /* 1231 * Every block group has an inode bitmap, a block 1232 * bitmap, and an inode table. 1233 */ 1234 overhead += (sbi->s_groups_count * 1235 (2 + sbi->s_itb_per_group)); 1236 sbi->s_overhead_last = overhead; 1237 smp_wmb(); 1238 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1239 } 1240 1241 buf->f_type = EXT2_SUPER_MAGIC; 1242 buf->f_bsize = sb->s_blocksize; 1243 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1244 buf->f_bfree = ext2_count_free_blocks(sb); 1245 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1246 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1247 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1248 buf->f_bavail = 0; 1249 buf->f_files = le32_to_cpu(es->s_inodes_count); 1250 buf->f_ffree = ext2_count_free_inodes(sb); 1251 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1252 buf->f_namelen = EXT2_NAME_LEN; 1253 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1254 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1255 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1256 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1257 return 0; 1258 } 1259 1260 static int ext2_get_sb(struct file_system_type *fs_type, 1261 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 1262 { 1263 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt); 1264 } 1265 1266 #ifdef CONFIG_QUOTA 1267 1268 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1269 * acquiring the locks... As quota files are never truncated and quota code 1270 * itself serializes the operations (and noone else should touch the files) 1271 * we don't have to be afraid of races */ 1272 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1273 size_t len, loff_t off) 1274 { 1275 struct inode *inode = sb_dqopt(sb)->files[type]; 1276 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1277 int err = 0; 1278 int offset = off & (sb->s_blocksize - 1); 1279 int tocopy; 1280 size_t toread; 1281 struct buffer_head tmp_bh; 1282 struct buffer_head *bh; 1283 loff_t i_size = i_size_read(inode); 1284 1285 if (off > i_size) 1286 return 0; 1287 if (off+len > i_size) 1288 len = i_size-off; 1289 toread = len; 1290 while (toread > 0) { 1291 tocopy = sb->s_blocksize - offset < toread ? 1292 sb->s_blocksize - offset : toread; 1293 1294 tmp_bh.b_state = 0; 1295 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1296 if (err < 0) 1297 return err; 1298 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1299 memset(data, 0, tocopy); 1300 else { 1301 bh = sb_bread(sb, tmp_bh.b_blocknr); 1302 if (!bh) 1303 return -EIO; 1304 memcpy(data, bh->b_data+offset, tocopy); 1305 brelse(bh); 1306 } 1307 offset = 0; 1308 toread -= tocopy; 1309 data += tocopy; 1310 blk++; 1311 } 1312 return len; 1313 } 1314 1315 /* Write to quotafile */ 1316 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1317 const char *data, size_t len, loff_t off) 1318 { 1319 struct inode *inode = sb_dqopt(sb)->files[type]; 1320 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1321 int err = 0; 1322 int offset = off & (sb->s_blocksize - 1); 1323 int tocopy; 1324 size_t towrite = len; 1325 struct buffer_head tmp_bh; 1326 struct buffer_head *bh; 1327 1328 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 1329 while (towrite > 0) { 1330 tocopy = sb->s_blocksize - offset < towrite ? 1331 sb->s_blocksize - offset : towrite; 1332 1333 tmp_bh.b_state = 0; 1334 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1335 if (err < 0) 1336 goto out; 1337 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1338 bh = sb_bread(sb, tmp_bh.b_blocknr); 1339 else 1340 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1341 if (!bh) { 1342 err = -EIO; 1343 goto out; 1344 } 1345 lock_buffer(bh); 1346 memcpy(bh->b_data+offset, data, tocopy); 1347 flush_dcache_page(bh->b_page); 1348 set_buffer_uptodate(bh); 1349 mark_buffer_dirty(bh); 1350 unlock_buffer(bh); 1351 brelse(bh); 1352 offset = 0; 1353 towrite -= tocopy; 1354 data += tocopy; 1355 blk++; 1356 } 1357 out: 1358 if (len == towrite) 1359 return err; 1360 if (inode->i_size < off+len-towrite) 1361 i_size_write(inode, off+len-towrite); 1362 inode->i_version++; 1363 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1364 mark_inode_dirty(inode); 1365 mutex_unlock(&inode->i_mutex); 1366 return len - towrite; 1367 } 1368 1369 #endif 1370 1371 static struct file_system_type ext2_fs_type = { 1372 .owner = THIS_MODULE, 1373 .name = "ext2", 1374 .get_sb = ext2_get_sb, 1375 .kill_sb = kill_block_super, 1376 .fs_flags = FS_REQUIRES_DEV, 1377 }; 1378 1379 static int __init init_ext2_fs(void) 1380 { 1381 int err = init_ext2_xattr(); 1382 if (err) 1383 return err; 1384 err = init_inodecache(); 1385 if (err) 1386 goto out1; 1387 err = register_filesystem(&ext2_fs_type); 1388 if (err) 1389 goto out; 1390 return 0; 1391 out: 1392 destroy_inodecache(); 1393 out1: 1394 exit_ext2_xattr(); 1395 return err; 1396 } 1397 1398 static void __exit exit_ext2_fs(void) 1399 { 1400 unregister_filesystem(&ext2_fs_type); 1401 destroy_inodecache(); 1402 exit_ext2_xattr(); 1403 } 1404 1405 module_init(init_ext2_fs) 1406 module_exit(exit_ext2_fs) 1407