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 error (device %s): %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 printk("Remounting filesystem read-only\n"); 70 sb->s_flags |= MS_RDONLY; 71 } 72 } 73 74 void ext2_warning (struct super_block * sb, const char * function, 75 const char * fmt, ...) 76 { 77 va_list args; 78 79 va_start(args, fmt); 80 printk(KERN_WARNING "EXT2-fs warning (device %s): %s: ", 81 sb->s_id, function); 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_warning(sb, __func__, 95 "updating to rev %d because of new feature flag, " 96 "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 #ifdef CONFIG_EXT2_FS_POSIX_ACL 156 ei->i_acl = EXT2_ACL_NOT_CACHED; 157 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 158 #endif 159 ei->i_block_alloc_info = NULL; 160 ei->vfs_inode.i_version = 1; 161 return &ei->vfs_inode; 162 } 163 164 static void ext2_destroy_inode(struct inode *inode) 165 { 166 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 167 } 168 169 static void init_once(void *foo) 170 { 171 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 172 173 rwlock_init(&ei->i_meta_lock); 174 #ifdef CONFIG_EXT2_FS_XATTR 175 init_rwsem(&ei->xattr_sem); 176 #endif 177 mutex_init(&ei->truncate_mutex); 178 inode_init_once(&ei->vfs_inode); 179 } 180 181 static int init_inodecache(void) 182 { 183 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 184 sizeof(struct ext2_inode_info), 185 0, (SLAB_RECLAIM_ACCOUNT| 186 SLAB_MEM_SPREAD), 187 init_once); 188 if (ext2_inode_cachep == NULL) 189 return -ENOMEM; 190 return 0; 191 } 192 193 static void destroy_inodecache(void) 194 { 195 kmem_cache_destroy(ext2_inode_cachep); 196 } 197 198 static void ext2_clear_inode(struct inode *inode) 199 { 200 struct ext2_block_alloc_info *rsv = EXT2_I(inode)->i_block_alloc_info; 201 #ifdef CONFIG_EXT2_FS_POSIX_ACL 202 struct ext2_inode_info *ei = EXT2_I(inode); 203 204 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) { 205 posix_acl_release(ei->i_acl); 206 ei->i_acl = EXT2_ACL_NOT_CACHED; 207 } 208 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) { 209 posix_acl_release(ei->i_default_acl); 210 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 211 } 212 #endif 213 ext2_discard_reservation(inode); 214 EXT2_I(inode)->i_block_alloc_info = NULL; 215 if (unlikely(rsv)) 216 kfree(rsv); 217 } 218 219 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs) 220 { 221 struct super_block *sb = vfs->mnt_sb; 222 struct ext2_sb_info *sbi = EXT2_SB(sb); 223 struct ext2_super_block *es = sbi->s_es; 224 unsigned long def_mount_opts; 225 226 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 227 228 if (sbi->s_sb_block != 1) 229 seq_printf(seq, ",sb=%lu", sbi->s_sb_block); 230 if (test_opt(sb, MINIX_DF)) 231 seq_puts(seq, ",minixdf"); 232 if (test_opt(sb, GRPID)) 233 seq_puts(seq, ",grpid"); 234 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS)) 235 seq_puts(seq, ",nogrpid"); 236 if (sbi->s_resuid != EXT2_DEF_RESUID || 237 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) { 238 seq_printf(seq, ",resuid=%u", sbi->s_resuid); 239 } 240 if (sbi->s_resgid != EXT2_DEF_RESGID || 241 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) { 242 seq_printf(seq, ",resgid=%u", sbi->s_resgid); 243 } 244 if (test_opt(sb, ERRORS_RO)) { 245 int def_errors = le16_to_cpu(es->s_errors); 246 247 if (def_errors == EXT2_ERRORS_PANIC || 248 def_errors == EXT2_ERRORS_CONTINUE) { 249 seq_puts(seq, ",errors=remount-ro"); 250 } 251 } 252 if (test_opt(sb, ERRORS_CONT)) 253 seq_puts(seq, ",errors=continue"); 254 if (test_opt(sb, ERRORS_PANIC)) 255 seq_puts(seq, ",errors=panic"); 256 if (test_opt(sb, NO_UID32)) 257 seq_puts(seq, ",nouid32"); 258 if (test_opt(sb, DEBUG)) 259 seq_puts(seq, ",debug"); 260 if (test_opt(sb, OLDALLOC)) 261 seq_puts(seq, ",oldalloc"); 262 263 #ifdef CONFIG_EXT2_FS_XATTR 264 if (test_opt(sb, XATTR_USER)) 265 seq_puts(seq, ",user_xattr"); 266 if (!test_opt(sb, XATTR_USER) && 267 (def_mount_opts & EXT2_DEFM_XATTR_USER)) { 268 seq_puts(seq, ",nouser_xattr"); 269 } 270 #endif 271 272 #ifdef CONFIG_EXT2_FS_POSIX_ACL 273 if (test_opt(sb, POSIX_ACL)) 274 seq_puts(seq, ",acl"); 275 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL)) 276 seq_puts(seq, ",noacl"); 277 #endif 278 279 if (test_opt(sb, NOBH)) 280 seq_puts(seq, ",nobh"); 281 282 #if defined(CONFIG_QUOTA) 283 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 284 seq_puts(seq, ",usrquota"); 285 286 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 287 seq_puts(seq, ",grpquota"); 288 #endif 289 290 #if defined(CONFIG_EXT2_FS_XIP) 291 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 292 seq_puts(seq, ",xip"); 293 #endif 294 295 if (!test_opt(sb, RESERVATION)) 296 seq_puts(seq, ",noreservation"); 297 298 return 0; 299 } 300 301 #ifdef CONFIG_QUOTA 302 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 303 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 304 #endif 305 306 static const struct super_operations ext2_sops = { 307 .alloc_inode = ext2_alloc_inode, 308 .destroy_inode = ext2_destroy_inode, 309 .write_inode = ext2_write_inode, 310 .delete_inode = ext2_delete_inode, 311 .put_super = ext2_put_super, 312 .write_super = ext2_write_super, 313 .sync_fs = ext2_sync_fs, 314 .statfs = ext2_statfs, 315 .remount_fs = ext2_remount, 316 .clear_inode = ext2_clear_inode, 317 .show_options = ext2_show_options, 318 #ifdef CONFIG_QUOTA 319 .quota_read = ext2_quota_read, 320 .quota_write = ext2_quota_write, 321 #endif 322 }; 323 324 static struct inode *ext2_nfs_get_inode(struct super_block *sb, 325 u64 ino, u32 generation) 326 { 327 struct inode *inode; 328 329 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 330 return ERR_PTR(-ESTALE); 331 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 332 return ERR_PTR(-ESTALE); 333 334 /* iget isn't really right if the inode is currently unallocated!! 335 * ext2_read_inode currently does appropriate checks, but 336 * it might be "neater" to call ext2_get_inode first and check 337 * if the inode is valid..... 338 */ 339 inode = ext2_iget(sb, ino); 340 if (IS_ERR(inode)) 341 return ERR_CAST(inode); 342 if (generation && inode->i_generation != generation) { 343 /* we didn't find the right inode.. */ 344 iput(inode); 345 return ERR_PTR(-ESTALE); 346 } 347 return inode; 348 } 349 350 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid, 351 int fh_len, int fh_type) 352 { 353 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 354 ext2_nfs_get_inode); 355 } 356 357 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, 358 int fh_len, int fh_type) 359 { 360 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 361 ext2_nfs_get_inode); 362 } 363 364 /* Yes, most of these are left as NULL!! 365 * A NULL value implies the default, which works with ext2-like file 366 * systems, but can be improved upon. 367 * Currently only get_parent is required. 368 */ 369 static const struct export_operations ext2_export_ops = { 370 .fh_to_dentry = ext2_fh_to_dentry, 371 .fh_to_parent = ext2_fh_to_parent, 372 .get_parent = ext2_get_parent, 373 }; 374 375 static unsigned long get_sb_block(void **data) 376 { 377 unsigned long sb_block; 378 char *options = (char *) *data; 379 380 if (!options || strncmp(options, "sb=", 3) != 0) 381 return 1; /* Default location */ 382 options += 3; 383 sb_block = simple_strtoul(options, &options, 0); 384 if (*options && *options != ',') { 385 printk("EXT2-fs: Invalid sb specification: %s\n", 386 (char *) *data); 387 return 1; 388 } 389 if (*options == ',') 390 options++; 391 *data = (void *) options; 392 return sb_block; 393 } 394 395 enum { 396 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 397 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 398 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 399 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 400 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, 401 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation 402 }; 403 404 static const match_table_t tokens = { 405 {Opt_bsd_df, "bsddf"}, 406 {Opt_minix_df, "minixdf"}, 407 {Opt_grpid, "grpid"}, 408 {Opt_grpid, "bsdgroups"}, 409 {Opt_nogrpid, "nogrpid"}, 410 {Opt_nogrpid, "sysvgroups"}, 411 {Opt_resgid, "resgid=%u"}, 412 {Opt_resuid, "resuid=%u"}, 413 {Opt_sb, "sb=%u"}, 414 {Opt_err_cont, "errors=continue"}, 415 {Opt_err_panic, "errors=panic"}, 416 {Opt_err_ro, "errors=remount-ro"}, 417 {Opt_nouid32, "nouid32"}, 418 {Opt_nocheck, "check=none"}, 419 {Opt_nocheck, "nocheck"}, 420 {Opt_debug, "debug"}, 421 {Opt_oldalloc, "oldalloc"}, 422 {Opt_orlov, "orlov"}, 423 {Opt_nobh, "nobh"}, 424 {Opt_user_xattr, "user_xattr"}, 425 {Opt_nouser_xattr, "nouser_xattr"}, 426 {Opt_acl, "acl"}, 427 {Opt_noacl, "noacl"}, 428 {Opt_xip, "xip"}, 429 {Opt_grpquota, "grpquota"}, 430 {Opt_ignore, "noquota"}, 431 {Opt_quota, "quota"}, 432 {Opt_usrquota, "usrquota"}, 433 {Opt_reservation, "reservation"}, 434 {Opt_noreservation, "noreservation"}, 435 {Opt_err, NULL} 436 }; 437 438 static int parse_options (char * options, 439 struct ext2_sb_info *sbi) 440 { 441 char * p; 442 substring_t args[MAX_OPT_ARGS]; 443 int option; 444 445 if (!options) 446 return 1; 447 448 while ((p = strsep (&options, ",")) != NULL) { 449 int token; 450 if (!*p) 451 continue; 452 453 token = match_token(p, tokens, args); 454 switch (token) { 455 case Opt_bsd_df: 456 clear_opt (sbi->s_mount_opt, MINIX_DF); 457 break; 458 case Opt_minix_df: 459 set_opt (sbi->s_mount_opt, MINIX_DF); 460 break; 461 case Opt_grpid: 462 set_opt (sbi->s_mount_opt, GRPID); 463 break; 464 case Opt_nogrpid: 465 clear_opt (sbi->s_mount_opt, GRPID); 466 break; 467 case Opt_resuid: 468 if (match_int(&args[0], &option)) 469 return 0; 470 sbi->s_resuid = option; 471 break; 472 case Opt_resgid: 473 if (match_int(&args[0], &option)) 474 return 0; 475 sbi->s_resgid = option; 476 break; 477 case Opt_sb: 478 /* handled by get_sb_block() instead of here */ 479 /* *sb_block = match_int(&args[0]); */ 480 break; 481 case Opt_err_panic: 482 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 483 clear_opt (sbi->s_mount_opt, ERRORS_RO); 484 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 485 break; 486 case Opt_err_ro: 487 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 488 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 489 set_opt (sbi->s_mount_opt, ERRORS_RO); 490 break; 491 case Opt_err_cont: 492 clear_opt (sbi->s_mount_opt, ERRORS_RO); 493 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 494 set_opt (sbi->s_mount_opt, ERRORS_CONT); 495 break; 496 case Opt_nouid32: 497 set_opt (sbi->s_mount_opt, NO_UID32); 498 break; 499 case Opt_nocheck: 500 clear_opt (sbi->s_mount_opt, CHECK); 501 break; 502 case Opt_debug: 503 set_opt (sbi->s_mount_opt, DEBUG); 504 break; 505 case Opt_oldalloc: 506 set_opt (sbi->s_mount_opt, OLDALLOC); 507 break; 508 case Opt_orlov: 509 clear_opt (sbi->s_mount_opt, OLDALLOC); 510 break; 511 case Opt_nobh: 512 set_opt (sbi->s_mount_opt, NOBH); 513 break; 514 #ifdef CONFIG_EXT2_FS_XATTR 515 case Opt_user_xattr: 516 set_opt (sbi->s_mount_opt, XATTR_USER); 517 break; 518 case Opt_nouser_xattr: 519 clear_opt (sbi->s_mount_opt, XATTR_USER); 520 break; 521 #else 522 case Opt_user_xattr: 523 case Opt_nouser_xattr: 524 printk("EXT2 (no)user_xattr options not supported\n"); 525 break; 526 #endif 527 #ifdef CONFIG_EXT2_FS_POSIX_ACL 528 case Opt_acl: 529 set_opt(sbi->s_mount_opt, POSIX_ACL); 530 break; 531 case Opt_noacl: 532 clear_opt(sbi->s_mount_opt, POSIX_ACL); 533 break; 534 #else 535 case Opt_acl: 536 case Opt_noacl: 537 printk("EXT2 (no)acl options not supported\n"); 538 break; 539 #endif 540 case Opt_xip: 541 #ifdef CONFIG_EXT2_FS_XIP 542 set_opt (sbi->s_mount_opt, XIP); 543 #else 544 printk("EXT2 xip option not supported\n"); 545 #endif 546 break; 547 548 #if defined(CONFIG_QUOTA) 549 case Opt_quota: 550 case Opt_usrquota: 551 set_opt(sbi->s_mount_opt, USRQUOTA); 552 break; 553 554 case Opt_grpquota: 555 set_opt(sbi->s_mount_opt, GRPQUOTA); 556 break; 557 #else 558 case Opt_quota: 559 case Opt_usrquota: 560 case Opt_grpquota: 561 printk(KERN_ERR 562 "EXT2-fs: quota operations not supported.\n"); 563 564 break; 565 #endif 566 567 case Opt_reservation: 568 set_opt(sbi->s_mount_opt, RESERVATION); 569 printk("reservations ON\n"); 570 break; 571 case Opt_noreservation: 572 clear_opt(sbi->s_mount_opt, RESERVATION); 573 printk("reservations OFF\n"); 574 break; 575 case Opt_ignore: 576 break; 577 default: 578 return 0; 579 } 580 } 581 return 1; 582 } 583 584 static int ext2_setup_super (struct super_block * sb, 585 struct ext2_super_block * es, 586 int read_only) 587 { 588 int res = 0; 589 struct ext2_sb_info *sbi = EXT2_SB(sb); 590 591 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 592 printk ("EXT2-fs warning: revision level too high, " 593 "forcing read-only mode\n"); 594 res = MS_RDONLY; 595 } 596 if (read_only) 597 return res; 598 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 599 printk ("EXT2-fs warning: mounting unchecked fs, " 600 "running e2fsck is recommended\n"); 601 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 602 printk ("EXT2-fs warning: mounting fs with errors, " 603 "running e2fsck is recommended\n"); 604 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 605 le16_to_cpu(es->s_mnt_count) >= 606 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 607 printk ("EXT2-fs warning: maximal mount count reached, " 608 "running e2fsck is recommended\n"); 609 else if (le32_to_cpu(es->s_checkinterval) && 610 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds())) 611 printk ("EXT2-fs warning: checktime reached, " 612 "running e2fsck is recommended\n"); 613 if (!le16_to_cpu(es->s_max_mnt_count)) 614 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 615 le16_add_cpu(&es->s_mnt_count, 1); 616 ext2_write_super(sb); 617 if (test_opt (sb, DEBUG)) 618 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, " 619 "bpg=%lu, ipg=%lu, mo=%04lx]\n", 620 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 621 sbi->s_frag_size, 622 sbi->s_groups_count, 623 EXT2_BLOCKS_PER_GROUP(sb), 624 EXT2_INODES_PER_GROUP(sb), 625 sbi->s_mount_opt); 626 return res; 627 } 628 629 static int ext2_check_descriptors(struct super_block *sb) 630 { 631 int i; 632 struct ext2_sb_info *sbi = EXT2_SB(sb); 633 634 ext2_debug ("Checking group descriptors"); 635 636 for (i = 0; i < sbi->s_groups_count; i++) { 637 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL); 638 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i); 639 ext2_fsblk_t last_block; 640 641 if (i == sbi->s_groups_count - 1) 642 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 643 else 644 last_block = first_block + 645 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 646 647 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 648 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 649 { 650 ext2_error (sb, "ext2_check_descriptors", 651 "Block bitmap for group %d" 652 " not in group (block %lu)!", 653 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 654 return 0; 655 } 656 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 657 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 658 { 659 ext2_error (sb, "ext2_check_descriptors", 660 "Inode bitmap for group %d" 661 " not in group (block %lu)!", 662 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 663 return 0; 664 } 665 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 666 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 > 667 last_block) 668 { 669 ext2_error (sb, "ext2_check_descriptors", 670 "Inode table for group %d" 671 " not in group (block %lu)!", 672 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 673 return 0; 674 } 675 } 676 return 1; 677 } 678 679 /* 680 * Maximal file size. There is a direct, and {,double-,triple-}indirect 681 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 682 * We need to be 1 filesystem block less than the 2^32 sector limit. 683 */ 684 static loff_t ext2_max_size(int bits) 685 { 686 loff_t res = EXT2_NDIR_BLOCKS; 687 int meta_blocks; 688 loff_t upper_limit; 689 690 /* This is calculated to be the largest file size for a 691 * dense, file such that the total number of 692 * sectors in the file, including data and all indirect blocks, 693 * does not exceed 2^32 -1 694 * __u32 i_blocks representing the total number of 695 * 512 bytes blocks of the file 696 */ 697 upper_limit = (1LL << 32) - 1; 698 699 /* total blocks in file system block size */ 700 upper_limit >>= (bits - 9); 701 702 703 /* indirect blocks */ 704 meta_blocks = 1; 705 /* double indirect blocks */ 706 meta_blocks += 1 + (1LL << (bits-2)); 707 /* tripple indirect blocks */ 708 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2))); 709 710 upper_limit -= meta_blocks; 711 upper_limit <<= bits; 712 713 res += 1LL << (bits-2); 714 res += 1LL << (2*(bits-2)); 715 res += 1LL << (3*(bits-2)); 716 res <<= bits; 717 if (res > upper_limit) 718 res = upper_limit; 719 720 if (res > MAX_LFS_FILESIZE) 721 res = MAX_LFS_FILESIZE; 722 723 return res; 724 } 725 726 static unsigned long descriptor_loc(struct super_block *sb, 727 unsigned long logic_sb_block, 728 int nr) 729 { 730 struct ext2_sb_info *sbi = EXT2_SB(sb); 731 unsigned long bg, first_meta_bg; 732 int has_super = 0; 733 734 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 735 736 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 737 nr < first_meta_bg) 738 return (logic_sb_block + nr + 1); 739 bg = sbi->s_desc_per_block * nr; 740 if (ext2_bg_has_super(sb, bg)) 741 has_super = 1; 742 743 return ext2_group_first_block_no(sb, bg) + has_super; 744 } 745 746 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 747 { 748 struct buffer_head * bh; 749 struct ext2_sb_info * sbi; 750 struct ext2_super_block * es; 751 struct inode *root; 752 unsigned long block; 753 unsigned long sb_block = get_sb_block(&data); 754 unsigned long logic_sb_block; 755 unsigned long offset = 0; 756 unsigned long def_mount_opts; 757 long ret = -EINVAL; 758 int blocksize = BLOCK_SIZE; 759 int db_count; 760 int i, j; 761 __le32 features; 762 int err; 763 764 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 765 if (!sbi) 766 return -ENOMEM; 767 768 sbi->s_blockgroup_lock = 769 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); 770 if (!sbi->s_blockgroup_lock) { 771 kfree(sbi); 772 return -ENOMEM; 773 } 774 sb->s_fs_info = sbi; 775 sbi->s_sb_block = sb_block; 776 777 /* 778 * See what the current blocksize for the device is, and 779 * use that as the blocksize. Otherwise (or if the blocksize 780 * is smaller than the default) use the default. 781 * This is important for devices that have a hardware 782 * sectorsize that is larger than the default. 783 */ 784 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 785 if (!blocksize) { 786 printk ("EXT2-fs: unable to set blocksize\n"); 787 goto failed_sbi; 788 } 789 790 /* 791 * If the superblock doesn't start on a hardware sector boundary, 792 * calculate the offset. 793 */ 794 if (blocksize != BLOCK_SIZE) { 795 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 796 offset = (sb_block*BLOCK_SIZE) % blocksize; 797 } else { 798 logic_sb_block = sb_block; 799 } 800 801 if (!(bh = sb_bread(sb, logic_sb_block))) { 802 printk ("EXT2-fs: unable to read superblock\n"); 803 goto failed_sbi; 804 } 805 /* 806 * Note: s_es must be initialized as soon as possible because 807 * some ext2 macro-instructions depend on its value 808 */ 809 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 810 sbi->s_es = es; 811 sb->s_magic = le16_to_cpu(es->s_magic); 812 813 if (sb->s_magic != EXT2_SUPER_MAGIC) 814 goto cantfind_ext2; 815 816 /* Set defaults before we parse the mount options */ 817 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 818 if (def_mount_opts & EXT2_DEFM_DEBUG) 819 set_opt(sbi->s_mount_opt, DEBUG); 820 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 821 set_opt(sbi->s_mount_opt, GRPID); 822 if (def_mount_opts & EXT2_DEFM_UID16) 823 set_opt(sbi->s_mount_opt, NO_UID32); 824 #ifdef CONFIG_EXT2_FS_XATTR 825 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 826 set_opt(sbi->s_mount_opt, XATTR_USER); 827 #endif 828 #ifdef CONFIG_EXT2_FS_POSIX_ACL 829 if (def_mount_opts & EXT2_DEFM_ACL) 830 set_opt(sbi->s_mount_opt, POSIX_ACL); 831 #endif 832 833 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 834 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 835 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE) 836 set_opt(sbi->s_mount_opt, ERRORS_CONT); 837 else 838 set_opt(sbi->s_mount_opt, ERRORS_RO); 839 840 sbi->s_resuid = le16_to_cpu(es->s_def_resuid); 841 sbi->s_resgid = le16_to_cpu(es->s_def_resgid); 842 843 set_opt(sbi->s_mount_opt, RESERVATION); 844 845 if (!parse_options ((char *) data, sbi)) 846 goto failed_mount; 847 848 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 849 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 850 MS_POSIXACL : 0); 851 852 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 853 EXT2_MOUNT_XIP if not */ 854 855 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 856 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 857 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 858 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 859 printk("EXT2-fs warning: feature flags set on rev 0 fs, " 860 "running e2fsck is recommended\n"); 861 /* 862 * Check feature flags regardless of the revision level, since we 863 * previously didn't change the revision level when setting the flags, 864 * so there is a chance incompat flags are set on a rev 0 filesystem. 865 */ 866 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 867 if (features) { 868 printk("EXT2-fs: %s: couldn't mount because of " 869 "unsupported optional features (%x).\n", 870 sb->s_id, le32_to_cpu(features)); 871 goto failed_mount; 872 } 873 if (!(sb->s_flags & MS_RDONLY) && 874 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 875 printk("EXT2-fs: %s: couldn't mount RDWR because of " 876 "unsupported optional features (%x).\n", 877 sb->s_id, le32_to_cpu(features)); 878 goto failed_mount; 879 } 880 881 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 882 883 if (ext2_use_xip(sb) && blocksize != PAGE_SIZE) { 884 if (!silent) 885 printk("XIP: Unsupported blocksize\n"); 886 goto failed_mount; 887 } 888 889 /* If the blocksize doesn't match, re-read the thing.. */ 890 if (sb->s_blocksize != blocksize) { 891 brelse(bh); 892 893 if (!sb_set_blocksize(sb, blocksize)) { 894 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); 895 goto failed_sbi; 896 } 897 898 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 899 offset = (sb_block*BLOCK_SIZE) % blocksize; 900 bh = sb_bread(sb, logic_sb_block); 901 if(!bh) { 902 printk("EXT2-fs: Couldn't read superblock on " 903 "2nd try.\n"); 904 goto failed_sbi; 905 } 906 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 907 sbi->s_es = es; 908 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 909 printk ("EXT2-fs: Magic mismatch, very weird !\n"); 910 goto failed_mount; 911 } 912 } 913 914 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 915 916 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 917 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 918 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 919 } else { 920 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 921 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 922 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 923 !is_power_of_2(sbi->s_inode_size) || 924 (sbi->s_inode_size > blocksize)) { 925 printk ("EXT2-fs: unsupported inode size: %d\n", 926 sbi->s_inode_size); 927 goto failed_mount; 928 } 929 } 930 931 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 932 le32_to_cpu(es->s_log_frag_size); 933 if (sbi->s_frag_size == 0) 934 goto cantfind_ext2; 935 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 936 937 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 938 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 939 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 940 941 if (EXT2_INODE_SIZE(sb) == 0) 942 goto cantfind_ext2; 943 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 944 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 945 goto cantfind_ext2; 946 sbi->s_itb_per_group = sbi->s_inodes_per_group / 947 sbi->s_inodes_per_block; 948 sbi->s_desc_per_block = sb->s_blocksize / 949 sizeof (struct ext2_group_desc); 950 sbi->s_sbh = bh; 951 sbi->s_mount_state = le16_to_cpu(es->s_state); 952 sbi->s_addr_per_block_bits = 953 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 954 sbi->s_desc_per_block_bits = 955 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 956 957 if (sb->s_magic != EXT2_SUPER_MAGIC) 958 goto cantfind_ext2; 959 960 if (sb->s_blocksize != bh->b_size) { 961 if (!silent) 962 printk ("VFS: Unsupported blocksize on dev " 963 "%s.\n", sb->s_id); 964 goto failed_mount; 965 } 966 967 if (sb->s_blocksize != sbi->s_frag_size) { 968 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n", 969 sbi->s_frag_size, sb->s_blocksize); 970 goto failed_mount; 971 } 972 973 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 974 printk ("EXT2-fs: #blocks per group too big: %lu\n", 975 sbi->s_blocks_per_group); 976 goto failed_mount; 977 } 978 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 979 printk ("EXT2-fs: #fragments per group too big: %lu\n", 980 sbi->s_frags_per_group); 981 goto failed_mount; 982 } 983 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 984 printk ("EXT2-fs: #inodes per group too big: %lu\n", 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 printk ("EXT2-fs: not enough memory\n"); 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 printk ("EXT2-fs: not enough memory\n"); 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 printk ("EXT2-fs: unable to read group descriptors\n"); 1014 goto failed_mount_group_desc; 1015 } 1016 } 1017 if (!ext2_check_descriptors (sb)) { 1018 printk ("EXT2-fs: group descriptors corrupted!\n"); 1019 goto failed_mount2; 1020 } 1021 sbi->s_gdb_count = db_count; 1022 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 1023 spin_lock_init(&sbi->s_next_gen_lock); 1024 1025 /* per fileystem reservation list head & lock */ 1026 spin_lock_init(&sbi->s_rsv_window_lock); 1027 sbi->s_rsv_window_root = RB_ROOT; 1028 /* 1029 * Add a single, static dummy reservation to the start of the 1030 * reservation window list --- it gives us a placeholder for 1031 * append-at-start-of-list which makes the allocation logic 1032 * _much_ simpler. 1033 */ 1034 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1035 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED; 1036 sbi->s_rsv_window_head.rsv_alloc_hit = 0; 1037 sbi->s_rsv_window_head.rsv_goal_size = 0; 1038 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head); 1039 1040 err = percpu_counter_init(&sbi->s_freeblocks_counter, 1041 ext2_count_free_blocks(sb)); 1042 if (!err) { 1043 err = percpu_counter_init(&sbi->s_freeinodes_counter, 1044 ext2_count_free_inodes(sb)); 1045 } 1046 if (!err) { 1047 err = percpu_counter_init(&sbi->s_dirs_counter, 1048 ext2_count_dirs(sb)); 1049 } 1050 if (err) { 1051 printk(KERN_ERR "EXT2-fs: insufficient memory\n"); 1052 goto failed_mount3; 1053 } 1054 /* 1055 * set up enough so that it can read an inode 1056 */ 1057 sb->s_op = &ext2_sops; 1058 sb->s_export_op = &ext2_export_ops; 1059 sb->s_xattr = ext2_xattr_handlers; 1060 root = ext2_iget(sb, EXT2_ROOT_INO); 1061 if (IS_ERR(root)) { 1062 ret = PTR_ERR(root); 1063 goto failed_mount3; 1064 } 1065 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 1066 iput(root); 1067 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n"); 1068 goto failed_mount3; 1069 } 1070 1071 sb->s_root = d_alloc_root(root); 1072 if (!sb->s_root) { 1073 iput(root); 1074 printk(KERN_ERR "EXT2-fs: get root inode failed\n"); 1075 ret = -ENOMEM; 1076 goto failed_mount3; 1077 } 1078 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 1079 ext2_warning(sb, __func__, 1080 "mounting ext3 filesystem as ext2"); 1081 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); 1082 return 0; 1083 1084 cantfind_ext2: 1085 if (!silent) 1086 printk("VFS: Can't find an ext2 filesystem on dev %s.\n", 1087 sb->s_id); 1088 goto failed_mount; 1089 failed_mount3: 1090 percpu_counter_destroy(&sbi->s_freeblocks_counter); 1091 percpu_counter_destroy(&sbi->s_freeinodes_counter); 1092 percpu_counter_destroy(&sbi->s_dirs_counter); 1093 failed_mount2: 1094 for (i = 0; i < db_count; i++) 1095 brelse(sbi->s_group_desc[i]); 1096 failed_mount_group_desc: 1097 kfree(sbi->s_group_desc); 1098 kfree(sbi->s_debts); 1099 failed_mount: 1100 brelse(bh); 1101 failed_sbi: 1102 sb->s_fs_info = NULL; 1103 kfree(sbi->s_blockgroup_lock); 1104 kfree(sbi); 1105 return ret; 1106 } 1107 1108 static void ext2_commit_super (struct super_block * sb, 1109 struct ext2_super_block * es) 1110 { 1111 es->s_wtime = cpu_to_le32(get_seconds()); 1112 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1113 sb->s_dirt = 0; 1114 } 1115 1116 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) 1117 { 1118 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1119 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1120 es->s_wtime = cpu_to_le32(get_seconds()); 1121 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 1122 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 1123 sb->s_dirt = 0; 1124 } 1125 1126 /* 1127 * In the second extended file system, it is not necessary to 1128 * write the super block since we use a mapping of the 1129 * disk super block in a buffer. 1130 * 1131 * However, this function is still used to set the fs valid 1132 * flags to 0. We need to set this flag to 0 since the fs 1133 * may have been checked while mounted and e2fsck may have 1134 * set s_state to EXT2_VALID_FS after some corrections. 1135 */ 1136 1137 static int ext2_sync_fs(struct super_block *sb, int wait) 1138 { 1139 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 1140 1141 lock_kernel(); 1142 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { 1143 ext2_debug("setting valid to 0\n"); 1144 es->s_state &= cpu_to_le16(~EXT2_VALID_FS); 1145 es->s_free_blocks_count = 1146 cpu_to_le32(ext2_count_free_blocks(sb)); 1147 es->s_free_inodes_count = 1148 cpu_to_le32(ext2_count_free_inodes(sb)); 1149 es->s_mtime = cpu_to_le32(get_seconds()); 1150 ext2_sync_super(sb, es); 1151 } else { 1152 ext2_commit_super(sb, es); 1153 } 1154 sb->s_dirt = 0; 1155 unlock_kernel(); 1156 1157 return 0; 1158 } 1159 1160 1161 void ext2_write_super(struct super_block *sb) 1162 { 1163 if (!(sb->s_flags & MS_RDONLY)) 1164 ext2_sync_fs(sb, 1); 1165 else 1166 sb->s_dirt = 0; 1167 } 1168 1169 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1170 { 1171 struct ext2_sb_info * sbi = EXT2_SB(sb); 1172 struct ext2_super_block * es; 1173 unsigned long old_mount_opt = sbi->s_mount_opt; 1174 struct ext2_mount_options old_opts; 1175 unsigned long old_sb_flags; 1176 int err; 1177 1178 lock_kernel(); 1179 1180 /* Store the old options */ 1181 old_sb_flags = sb->s_flags; 1182 old_opts.s_mount_opt = sbi->s_mount_opt; 1183 old_opts.s_resuid = sbi->s_resuid; 1184 old_opts.s_resgid = sbi->s_resgid; 1185 1186 /* 1187 * Allow the "check" option to be passed as a remount option. 1188 */ 1189 if (!parse_options (data, sbi)) { 1190 err = -EINVAL; 1191 goto restore_opts; 1192 } 1193 1194 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1195 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1196 1197 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 1198 EXT2_MOUNT_XIP if not */ 1199 1200 if ((ext2_use_xip(sb)) && (sb->s_blocksize != PAGE_SIZE)) { 1201 printk("XIP: Unsupported blocksize\n"); 1202 err = -EINVAL; 1203 goto restore_opts; 1204 } 1205 1206 es = sbi->s_es; 1207 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) != 1208 (old_mount_opt & EXT2_MOUNT_XIP)) && 1209 invalidate_inodes(sb)) { 1210 ext2_warning(sb, __func__, "refusing change of xip flag " 1211 "with busy inodes while remounting"); 1212 sbi->s_mount_opt &= ~EXT2_MOUNT_XIP; 1213 sbi->s_mount_opt |= old_mount_opt & EXT2_MOUNT_XIP; 1214 } 1215 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { 1216 unlock_kernel(); 1217 return 0; 1218 } 1219 if (*flags & MS_RDONLY) { 1220 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1221 !(sbi->s_mount_state & EXT2_VALID_FS)) { 1222 unlock_kernel(); 1223 return 0; 1224 } 1225 /* 1226 * OK, we are remounting a valid rw partition rdonly, so set 1227 * the rdonly flag and then mark the partition as valid again. 1228 */ 1229 es->s_state = cpu_to_le16(sbi->s_mount_state); 1230 es->s_mtime = cpu_to_le32(get_seconds()); 1231 } else { 1232 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1233 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1234 if (ret) { 1235 printk("EXT2-fs: %s: couldn't remount RDWR because of " 1236 "unsupported optional features (%x).\n", 1237 sb->s_id, le32_to_cpu(ret)); 1238 err = -EROFS; 1239 goto restore_opts; 1240 } 1241 /* 1242 * Mounting a RDONLY partition read-write, so reread and 1243 * store the current valid flag. (It may have been changed 1244 * by e2fsck since we originally mounted the partition.) 1245 */ 1246 sbi->s_mount_state = le16_to_cpu(es->s_state); 1247 if (!ext2_setup_super (sb, es, 0)) 1248 sb->s_flags &= ~MS_RDONLY; 1249 } 1250 ext2_sync_super(sb, es); 1251 unlock_kernel(); 1252 return 0; 1253 restore_opts: 1254 sbi->s_mount_opt = old_opts.s_mount_opt; 1255 sbi->s_resuid = old_opts.s_resuid; 1256 sbi->s_resgid = old_opts.s_resgid; 1257 sb->s_flags = old_sb_flags; 1258 unlock_kernel(); 1259 return err; 1260 } 1261 1262 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1263 { 1264 struct super_block *sb = dentry->d_sb; 1265 struct ext2_sb_info *sbi = EXT2_SB(sb); 1266 struct ext2_super_block *es = sbi->s_es; 1267 u64 fsid; 1268 1269 if (test_opt (sb, MINIX_DF)) 1270 sbi->s_overhead_last = 0; 1271 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) { 1272 unsigned long i, overhead = 0; 1273 smp_rmb(); 1274 1275 /* 1276 * Compute the overhead (FS structures). This is constant 1277 * for a given filesystem unless the number of block groups 1278 * changes so we cache the previous value until it does. 1279 */ 1280 1281 /* 1282 * All of the blocks before first_data_block are 1283 * overhead 1284 */ 1285 overhead = le32_to_cpu(es->s_first_data_block); 1286 1287 /* 1288 * Add the overhead attributed to the superblock and 1289 * block group descriptors. If the sparse superblocks 1290 * feature is turned on, then not all groups have this. 1291 */ 1292 for (i = 0; i < sbi->s_groups_count; i++) 1293 overhead += ext2_bg_has_super(sb, i) + 1294 ext2_bg_num_gdb(sb, i); 1295 1296 /* 1297 * Every block group has an inode bitmap, a block 1298 * bitmap, and an inode table. 1299 */ 1300 overhead += (sbi->s_groups_count * 1301 (2 + sbi->s_itb_per_group)); 1302 sbi->s_overhead_last = overhead; 1303 smp_wmb(); 1304 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count); 1305 } 1306 1307 buf->f_type = EXT2_SUPER_MAGIC; 1308 buf->f_bsize = sb->s_blocksize; 1309 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last; 1310 buf->f_bfree = ext2_count_free_blocks(sb); 1311 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree); 1312 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1313 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1314 buf->f_bavail = 0; 1315 buf->f_files = le32_to_cpu(es->s_inodes_count); 1316 buf->f_ffree = ext2_count_free_inodes(sb); 1317 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree); 1318 buf->f_namelen = EXT2_NAME_LEN; 1319 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1320 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1321 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1322 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1323 return 0; 1324 } 1325 1326 static int ext2_get_sb(struct file_system_type *fs_type, 1327 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 1328 { 1329 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt); 1330 } 1331 1332 #ifdef CONFIG_QUOTA 1333 1334 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1335 * acquiring the locks... As quota files are never truncated and quota code 1336 * itself serializes the operations (and noone else should touch the files) 1337 * we don't have to be afraid of races */ 1338 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1339 size_t len, loff_t off) 1340 { 1341 struct inode *inode = sb_dqopt(sb)->files[type]; 1342 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1343 int err = 0; 1344 int offset = off & (sb->s_blocksize - 1); 1345 int tocopy; 1346 size_t toread; 1347 struct buffer_head tmp_bh; 1348 struct buffer_head *bh; 1349 loff_t i_size = i_size_read(inode); 1350 1351 if (off > i_size) 1352 return 0; 1353 if (off+len > i_size) 1354 len = i_size-off; 1355 toread = len; 1356 while (toread > 0) { 1357 tocopy = sb->s_blocksize - offset < toread ? 1358 sb->s_blocksize - offset : toread; 1359 1360 tmp_bh.b_state = 0; 1361 tmp_bh.b_size = sb->s_blocksize; 1362 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1363 if (err < 0) 1364 return err; 1365 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1366 memset(data, 0, tocopy); 1367 else { 1368 bh = sb_bread(sb, tmp_bh.b_blocknr); 1369 if (!bh) 1370 return -EIO; 1371 memcpy(data, bh->b_data+offset, tocopy); 1372 brelse(bh); 1373 } 1374 offset = 0; 1375 toread -= tocopy; 1376 data += tocopy; 1377 blk++; 1378 } 1379 return len; 1380 } 1381 1382 /* Write to quotafile */ 1383 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1384 const char *data, size_t len, loff_t off) 1385 { 1386 struct inode *inode = sb_dqopt(sb)->files[type]; 1387 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1388 int err = 0; 1389 int offset = off & (sb->s_blocksize - 1); 1390 int tocopy; 1391 size_t towrite = len; 1392 struct buffer_head tmp_bh; 1393 struct buffer_head *bh; 1394 1395 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 1396 while (towrite > 0) { 1397 tocopy = sb->s_blocksize - offset < towrite ? 1398 sb->s_blocksize - offset : towrite; 1399 1400 tmp_bh.b_state = 0; 1401 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1402 if (err < 0) 1403 goto out; 1404 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1405 bh = sb_bread(sb, tmp_bh.b_blocknr); 1406 else 1407 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1408 if (!bh) { 1409 err = -EIO; 1410 goto out; 1411 } 1412 lock_buffer(bh); 1413 memcpy(bh->b_data+offset, data, tocopy); 1414 flush_dcache_page(bh->b_page); 1415 set_buffer_uptodate(bh); 1416 mark_buffer_dirty(bh); 1417 unlock_buffer(bh); 1418 brelse(bh); 1419 offset = 0; 1420 towrite -= tocopy; 1421 data += tocopy; 1422 blk++; 1423 } 1424 out: 1425 if (len == towrite) { 1426 mutex_unlock(&inode->i_mutex); 1427 return err; 1428 } 1429 if (inode->i_size < off+len-towrite) 1430 i_size_write(inode, off+len-towrite); 1431 inode->i_version++; 1432 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1433 mark_inode_dirty(inode); 1434 mutex_unlock(&inode->i_mutex); 1435 return len - towrite; 1436 } 1437 1438 #endif 1439 1440 static struct file_system_type ext2_fs_type = { 1441 .owner = THIS_MODULE, 1442 .name = "ext2", 1443 .get_sb = ext2_get_sb, 1444 .kill_sb = kill_block_super, 1445 .fs_flags = FS_REQUIRES_DEV, 1446 }; 1447 1448 static int __init init_ext2_fs(void) 1449 { 1450 int err = init_ext2_xattr(); 1451 if (err) 1452 return err; 1453 err = init_inodecache(); 1454 if (err) 1455 goto out1; 1456 err = register_filesystem(&ext2_fs_type); 1457 if (err) 1458 goto out; 1459 return 0; 1460 out: 1461 destroy_inodecache(); 1462 out1: 1463 exit_ext2_xattr(); 1464 return err; 1465 } 1466 1467 static void __exit exit_ext2_fs(void) 1468 { 1469 unregister_filesystem(&ext2_fs_type); 1470 destroy_inodecache(); 1471 exit_ext2_xattr(); 1472 } 1473 1474 module_init(init_ext2_fs) 1475 module_exit(exit_ext2_fs) 1476