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/smp_lock.h> 29 #include <linux/vfs.h> 30 #include <linux/seq_file.h> 31 #include <linux/mount.h> 32 #include <asm/uaccess.h> 33 #include "ext2.h" 34 #include "xattr.h" 35 #include "acl.h" 36 #include "xip.h" 37 38 static void ext2_sync_super(struct super_block *sb, 39 struct ext2_super_block *es); 40 static int ext2_remount (struct super_block * sb, int * flags, char * data); 41 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf); 42 43 void ext2_error (struct super_block * sb, const char * function, 44 const char * fmt, ...) 45 { 46 va_list args; 47 struct ext2_sb_info *sbi = EXT2_SB(sb); 48 struct ext2_super_block *es = sbi->s_es; 49 50 if (!(sb->s_flags & MS_RDONLY)) { 51 sbi->s_mount_state |= EXT2_ERROR_FS; 52 es->s_state = 53 cpu_to_le16(le16_to_cpu(es->s_state) | EXT2_ERROR_FS); 54 ext2_sync_super(sb, es); 55 } 56 57 va_start(args, fmt); 58 printk(KERN_CRIT "EXT2-fs error (device %s): %s: ",sb->s_id, function); 59 vprintk(fmt, args); 60 printk("\n"); 61 va_end(args); 62 63 if (test_opt(sb, ERRORS_PANIC)) 64 panic("EXT2-fs panic from previous error\n"); 65 if (test_opt(sb, ERRORS_RO)) { 66 printk("Remounting filesystem read-only\n"); 67 sb->s_flags |= MS_RDONLY; 68 } 69 } 70 71 void ext2_warning (struct super_block * sb, const char * function, 72 const char * fmt, ...) 73 { 74 va_list args; 75 76 va_start(args, fmt); 77 printk(KERN_WARNING "EXT2-fs warning (device %s): %s: ", 78 sb->s_id, function); 79 vprintk(fmt, args); 80 printk("\n"); 81 va_end(args); 82 } 83 84 void ext2_update_dynamic_rev(struct super_block *sb) 85 { 86 struct ext2_super_block *es = EXT2_SB(sb)->s_es; 87 88 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) 89 return; 90 91 ext2_warning(sb, __FUNCTION__, 92 "updating to rev %d because of new feature flag, " 93 "running e2fsck is recommended", 94 EXT2_DYNAMIC_REV); 95 96 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); 97 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); 98 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); 99 /* leave es->s_feature_*compat flags alone */ 100 /* es->s_uuid will be set by e2fsck if empty */ 101 102 /* 103 * The rest of the superblock fields should be zero, and if not it 104 * means they are likely already in use, so leave them alone. We 105 * can leave it up to e2fsck to clean up any inconsistencies there. 106 */ 107 } 108 109 static void ext2_put_super (struct super_block * sb) 110 { 111 int db_count; 112 int i; 113 struct ext2_sb_info *sbi = EXT2_SB(sb); 114 115 ext2_xattr_put_super(sb); 116 if (!(sb->s_flags & MS_RDONLY)) { 117 struct ext2_super_block *es = sbi->s_es; 118 119 es->s_state = cpu_to_le16(sbi->s_mount_state); 120 ext2_sync_super(sb, es); 121 } 122 db_count = sbi->s_gdb_count; 123 for (i = 0; i < db_count; i++) 124 if (sbi->s_group_desc[i]) 125 brelse (sbi->s_group_desc[i]); 126 kfree(sbi->s_group_desc); 127 kfree(sbi->s_debts); 128 percpu_counter_destroy(&sbi->s_freeblocks_counter); 129 percpu_counter_destroy(&sbi->s_freeinodes_counter); 130 percpu_counter_destroy(&sbi->s_dirs_counter); 131 brelse (sbi->s_sbh); 132 sb->s_fs_info = NULL; 133 kfree(sbi); 134 135 return; 136 } 137 138 static kmem_cache_t * ext2_inode_cachep; 139 140 static struct inode *ext2_alloc_inode(struct super_block *sb) 141 { 142 struct ext2_inode_info *ei; 143 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, SLAB_KERNEL); 144 if (!ei) 145 return NULL; 146 #ifdef CONFIG_EXT2_FS_POSIX_ACL 147 ei->i_acl = EXT2_ACL_NOT_CACHED; 148 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 149 #endif 150 ei->vfs_inode.i_version = 1; 151 return &ei->vfs_inode; 152 } 153 154 static void ext2_destroy_inode(struct inode *inode) 155 { 156 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode)); 157 } 158 159 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags) 160 { 161 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 162 163 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == 164 SLAB_CTOR_CONSTRUCTOR) { 165 rwlock_init(&ei->i_meta_lock); 166 #ifdef CONFIG_EXT2_FS_XATTR 167 init_rwsem(&ei->xattr_sem); 168 #endif 169 inode_init_once(&ei->vfs_inode); 170 } 171 } 172 173 static int init_inodecache(void) 174 { 175 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 176 sizeof(struct ext2_inode_info), 177 0, (SLAB_RECLAIM_ACCOUNT| 178 SLAB_MEM_SPREAD), 179 init_once, NULL); 180 if (ext2_inode_cachep == NULL) 181 return -ENOMEM; 182 return 0; 183 } 184 185 static void destroy_inodecache(void) 186 { 187 kmem_cache_destroy(ext2_inode_cachep); 188 } 189 190 static void ext2_clear_inode(struct inode *inode) 191 { 192 #ifdef CONFIG_EXT2_FS_POSIX_ACL 193 struct ext2_inode_info *ei = EXT2_I(inode); 194 195 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) { 196 posix_acl_release(ei->i_acl); 197 ei->i_acl = EXT2_ACL_NOT_CACHED; 198 } 199 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) { 200 posix_acl_release(ei->i_default_acl); 201 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 202 } 203 #endif 204 } 205 206 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs) 207 { 208 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb); 209 210 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID) 211 seq_puts(seq, ",grpid"); 212 213 #if defined(CONFIG_QUOTA) 214 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 215 seq_puts(seq, ",usrquota"); 216 217 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 218 seq_puts(seq, ",grpquota"); 219 #endif 220 221 #if defined(CONFIG_EXT2_FS_XIP) 222 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 223 seq_puts(seq, ",xip"); 224 #endif 225 226 return 0; 227 } 228 229 #ifdef CONFIG_QUOTA 230 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 231 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 232 #endif 233 234 static struct super_operations ext2_sops = { 235 .alloc_inode = ext2_alloc_inode, 236 .destroy_inode = ext2_destroy_inode, 237 .read_inode = ext2_read_inode, 238 .write_inode = ext2_write_inode, 239 .put_inode = ext2_put_inode, 240 .delete_inode = ext2_delete_inode, 241 .put_super = ext2_put_super, 242 .write_super = ext2_write_super, 243 .statfs = ext2_statfs, 244 .remount_fs = ext2_remount, 245 .clear_inode = ext2_clear_inode, 246 .show_options = ext2_show_options, 247 #ifdef CONFIG_QUOTA 248 .quota_read = ext2_quota_read, 249 .quota_write = ext2_quota_write, 250 #endif 251 }; 252 253 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp) 254 { 255 __u32 *objp = vobjp; 256 unsigned long ino = objp[0]; 257 __u32 generation = objp[1]; 258 struct inode *inode; 259 struct dentry *result; 260 261 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 262 return ERR_PTR(-ESTALE); 263 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 264 return ERR_PTR(-ESTALE); 265 266 /* iget isn't really right if the inode is currently unallocated!! 267 * ext2_read_inode currently does appropriate checks, but 268 * it might be "neater" to call ext2_get_inode first and check 269 * if the inode is valid..... 270 */ 271 inode = iget(sb, ino); 272 if (inode == NULL) 273 return ERR_PTR(-ENOMEM); 274 if (is_bad_inode(inode) || 275 (generation && inode->i_generation != generation)) { 276 /* we didn't find the right inode.. */ 277 iput(inode); 278 return ERR_PTR(-ESTALE); 279 } 280 /* now to find a dentry. 281 * If possible, get a well-connected one 282 */ 283 result = d_alloc_anon(inode); 284 if (!result) { 285 iput(inode); 286 return ERR_PTR(-ENOMEM); 287 } 288 return result; 289 } 290 291 /* Yes, most of these are left as NULL!! 292 * A NULL value implies the default, which works with ext2-like file 293 * systems, but can be improved upon. 294 * Currently only get_parent is required. 295 */ 296 static struct export_operations ext2_export_ops = { 297 .get_parent = ext2_get_parent, 298 .get_dentry = ext2_get_dentry, 299 }; 300 301 static unsigned long get_sb_block(void **data) 302 { 303 unsigned long sb_block; 304 char *options = (char *) *data; 305 306 if (!options || strncmp(options, "sb=", 3) != 0) 307 return 1; /* Default location */ 308 options += 3; 309 sb_block = simple_strtoul(options, &options, 0); 310 if (*options && *options != ',') { 311 printk("EXT2-fs: Invalid sb specification: %s\n", 312 (char *) *data); 313 return 1; 314 } 315 if (*options == ',') 316 options++; 317 *data = (void *) options; 318 return sb_block; 319 } 320 321 enum { 322 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 323 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 324 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 325 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 326 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, 327 Opt_usrquota, Opt_grpquota 328 }; 329 330 static match_table_t tokens = { 331 {Opt_bsd_df, "bsddf"}, 332 {Opt_minix_df, "minixdf"}, 333 {Opt_grpid, "grpid"}, 334 {Opt_grpid, "bsdgroups"}, 335 {Opt_nogrpid, "nogrpid"}, 336 {Opt_nogrpid, "sysvgroups"}, 337 {Opt_resgid, "resgid=%u"}, 338 {Opt_resuid, "resuid=%u"}, 339 {Opt_sb, "sb=%u"}, 340 {Opt_err_cont, "errors=continue"}, 341 {Opt_err_panic, "errors=panic"}, 342 {Opt_err_ro, "errors=remount-ro"}, 343 {Opt_nouid32, "nouid32"}, 344 {Opt_nocheck, "check=none"}, 345 {Opt_nocheck, "nocheck"}, 346 {Opt_debug, "debug"}, 347 {Opt_oldalloc, "oldalloc"}, 348 {Opt_orlov, "orlov"}, 349 {Opt_nobh, "nobh"}, 350 {Opt_user_xattr, "user_xattr"}, 351 {Opt_nouser_xattr, "nouser_xattr"}, 352 {Opt_acl, "acl"}, 353 {Opt_noacl, "noacl"}, 354 {Opt_xip, "xip"}, 355 {Opt_grpquota, "grpquota"}, 356 {Opt_ignore, "noquota"}, 357 {Opt_quota, "quota"}, 358 {Opt_usrquota, "usrquota"}, 359 {Opt_err, NULL} 360 }; 361 362 static int parse_options (char * options, 363 struct ext2_sb_info *sbi) 364 { 365 char * p; 366 substring_t args[MAX_OPT_ARGS]; 367 unsigned long kind = EXT2_MOUNT_ERRORS_CONT; 368 int option; 369 370 if (!options) 371 return 1; 372 373 while ((p = strsep (&options, ",")) != NULL) { 374 int token; 375 if (!*p) 376 continue; 377 378 token = match_token(p, tokens, args); 379 switch (token) { 380 case Opt_bsd_df: 381 clear_opt (sbi->s_mount_opt, MINIX_DF); 382 break; 383 case Opt_minix_df: 384 set_opt (sbi->s_mount_opt, MINIX_DF); 385 break; 386 case Opt_grpid: 387 set_opt (sbi->s_mount_opt, GRPID); 388 break; 389 case Opt_nogrpid: 390 clear_opt (sbi->s_mount_opt, GRPID); 391 break; 392 case Opt_resuid: 393 if (match_int(&args[0], &option)) 394 return 0; 395 sbi->s_resuid = option; 396 break; 397 case Opt_resgid: 398 if (match_int(&args[0], &option)) 399 return 0; 400 sbi->s_resgid = option; 401 break; 402 case Opt_sb: 403 /* handled by get_sb_block() instead of here */ 404 /* *sb_block = match_int(&args[0]); */ 405 break; 406 case Opt_err_panic: 407 kind = EXT2_MOUNT_ERRORS_PANIC; 408 break; 409 case Opt_err_ro: 410 kind = EXT2_MOUNT_ERRORS_RO; 411 break; 412 case Opt_err_cont: 413 kind = EXT2_MOUNT_ERRORS_CONT; 414 break; 415 case Opt_nouid32: 416 set_opt (sbi->s_mount_opt, NO_UID32); 417 break; 418 case Opt_nocheck: 419 clear_opt (sbi->s_mount_opt, CHECK); 420 break; 421 case Opt_debug: 422 set_opt (sbi->s_mount_opt, DEBUG); 423 break; 424 case Opt_oldalloc: 425 set_opt (sbi->s_mount_opt, OLDALLOC); 426 break; 427 case Opt_orlov: 428 clear_opt (sbi->s_mount_opt, OLDALLOC); 429 break; 430 case Opt_nobh: 431 set_opt (sbi->s_mount_opt, NOBH); 432 break; 433 #ifdef CONFIG_EXT2_FS_XATTR 434 case Opt_user_xattr: 435 set_opt (sbi->s_mount_opt, XATTR_USER); 436 break; 437 case Opt_nouser_xattr: 438 clear_opt (sbi->s_mount_opt, XATTR_USER); 439 break; 440 #else 441 case Opt_user_xattr: 442 case Opt_nouser_xattr: 443 printk("EXT2 (no)user_xattr options not supported\n"); 444 break; 445 #endif 446 #ifdef CONFIG_EXT2_FS_POSIX_ACL 447 case Opt_acl: 448 set_opt(sbi->s_mount_opt, POSIX_ACL); 449 break; 450 case Opt_noacl: 451 clear_opt(sbi->s_mount_opt, POSIX_ACL); 452 break; 453 #else 454 case Opt_acl: 455 case Opt_noacl: 456 printk("EXT2 (no)acl options not supported\n"); 457 break; 458 #endif 459 case Opt_xip: 460 #ifdef CONFIG_EXT2_FS_XIP 461 set_opt (sbi->s_mount_opt, XIP); 462 #else 463 printk("EXT2 xip option not supported\n"); 464 #endif 465 break; 466 467 #if defined(CONFIG_QUOTA) 468 case Opt_quota: 469 case Opt_usrquota: 470 set_opt(sbi->s_mount_opt, USRQUOTA); 471 break; 472 473 case Opt_grpquota: 474 set_opt(sbi->s_mount_opt, GRPQUOTA); 475 break; 476 #else 477 case Opt_quota: 478 case Opt_usrquota: 479 case Opt_grpquota: 480 printk(KERN_ERR 481 "EXT2-fs: quota operations not supported.\n"); 482 483 break; 484 #endif 485 486 case Opt_ignore: 487 break; 488 default: 489 return 0; 490 } 491 } 492 sbi->s_mount_opt |= kind; 493 return 1; 494 } 495 496 static int ext2_setup_super (struct super_block * sb, 497 struct ext2_super_block * es, 498 int read_only) 499 { 500 int res = 0; 501 struct ext2_sb_info *sbi = EXT2_SB(sb); 502 503 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 504 printk ("EXT2-fs warning: revision level too high, " 505 "forcing read-only mode\n"); 506 res = MS_RDONLY; 507 } 508 if (read_only) 509 return res; 510 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 511 printk ("EXT2-fs warning: mounting unchecked fs, " 512 "running e2fsck is recommended\n"); 513 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 514 printk ("EXT2-fs warning: mounting fs with errors, " 515 "running e2fsck is recommended\n"); 516 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 517 le16_to_cpu(es->s_mnt_count) >= 518 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 519 printk ("EXT2-fs warning: maximal mount count reached, " 520 "running e2fsck is recommended\n"); 521 else if (le32_to_cpu(es->s_checkinterval) && 522 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds())) 523 printk ("EXT2-fs warning: checktime reached, " 524 "running e2fsck is recommended\n"); 525 if (!le16_to_cpu(es->s_max_mnt_count)) 526 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 527 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1); 528 ext2_write_super(sb); 529 if (test_opt (sb, DEBUG)) 530 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, " 531 "bpg=%lu, ipg=%lu, mo=%04lx]\n", 532 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 533 sbi->s_frag_size, 534 sbi->s_groups_count, 535 EXT2_BLOCKS_PER_GROUP(sb), 536 EXT2_INODES_PER_GROUP(sb), 537 sbi->s_mount_opt); 538 return res; 539 } 540 541 static int ext2_check_descriptors (struct super_block * sb) 542 { 543 int i; 544 int desc_block = 0; 545 struct ext2_sb_info *sbi = EXT2_SB(sb); 546 unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block); 547 unsigned long last_block; 548 struct ext2_group_desc * gdp = NULL; 549 550 ext2_debug ("Checking group descriptors"); 551 552 for (i = 0; i < sbi->s_groups_count; i++) 553 { 554 if (i == sbi->s_groups_count - 1) 555 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 556 else 557 last_block = first_block + 558 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 559 560 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0) 561 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data; 562 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 563 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 564 { 565 ext2_error (sb, "ext2_check_descriptors", 566 "Block bitmap for group %d" 567 " not in group (block %lu)!", 568 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 569 return 0; 570 } 571 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 572 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 573 { 574 ext2_error (sb, "ext2_check_descriptors", 575 "Inode bitmap for group %d" 576 " not in group (block %lu)!", 577 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 578 return 0; 579 } 580 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 581 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group > 582 last_block) 583 { 584 ext2_error (sb, "ext2_check_descriptors", 585 "Inode table for group %d" 586 " not in group (block %lu)!", 587 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 588 return 0; 589 } 590 first_block += EXT2_BLOCKS_PER_GROUP(sb); 591 gdp++; 592 } 593 return 1; 594 } 595 596 #define log2(n) ffz(~(n)) 597 598 /* 599 * Maximal file size. There is a direct, and {,double-,triple-}indirect 600 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 601 * We need to be 1 filesystem block less than the 2^32 sector limit. 602 */ 603 static loff_t ext2_max_size(int bits) 604 { 605 loff_t res = EXT2_NDIR_BLOCKS; 606 /* This constant is calculated to be the largest file size for a 607 * dense, 4k-blocksize file such that the total number of 608 * sectors in the file, including data and all indirect blocks, 609 * does not exceed 2^32. */ 610 const loff_t upper_limit = 0x1ff7fffd000LL; 611 612 res += 1LL << (bits-2); 613 res += 1LL << (2*(bits-2)); 614 res += 1LL << (3*(bits-2)); 615 res <<= bits; 616 if (res > upper_limit) 617 res = upper_limit; 618 return res; 619 } 620 621 static unsigned long descriptor_loc(struct super_block *sb, 622 unsigned long logic_sb_block, 623 int nr) 624 { 625 struct ext2_sb_info *sbi = EXT2_SB(sb); 626 unsigned long bg, first_data_block, first_meta_bg; 627 int has_super = 0; 628 629 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block); 630 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 631 632 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 633 nr < first_meta_bg) 634 return (logic_sb_block + nr + 1); 635 bg = sbi->s_desc_per_block * nr; 636 if (ext2_bg_has_super(sb, bg)) 637 has_super = 1; 638 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group)); 639 } 640 641 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 642 { 643 struct buffer_head * bh; 644 struct ext2_sb_info * sbi; 645 struct ext2_super_block * es; 646 struct inode *root; 647 unsigned long block; 648 unsigned long sb_block = get_sb_block(&data); 649 unsigned long logic_sb_block; 650 unsigned long offset = 0; 651 unsigned long def_mount_opts; 652 int blocksize = BLOCK_SIZE; 653 int db_count; 654 int i, j; 655 __le32 features; 656 657 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 658 if (!sbi) 659 return -ENOMEM; 660 sb->s_fs_info = sbi; 661 662 /* 663 * See what the current blocksize for the device is, and 664 * use that as the blocksize. Otherwise (or if the blocksize 665 * is smaller than the default) use the default. 666 * This is important for devices that have a hardware 667 * sectorsize that is larger than the default. 668 */ 669 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 670 if (!blocksize) { 671 printk ("EXT2-fs: unable to set blocksize\n"); 672 goto failed_sbi; 673 } 674 675 /* 676 * If the superblock doesn't start on a hardware sector boundary, 677 * calculate the offset. 678 */ 679 if (blocksize != BLOCK_SIZE) { 680 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 681 offset = (sb_block*BLOCK_SIZE) % blocksize; 682 } else { 683 logic_sb_block = sb_block; 684 } 685 686 if (!(bh = sb_bread(sb, logic_sb_block))) { 687 printk ("EXT2-fs: unable to read superblock\n"); 688 goto failed_sbi; 689 } 690 /* 691 * Note: s_es must be initialized as soon as possible because 692 * some ext2 macro-instructions depend on its value 693 */ 694 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 695 sbi->s_es = es; 696 sb->s_magic = le16_to_cpu(es->s_magic); 697 698 if (sb->s_magic != EXT2_SUPER_MAGIC) 699 goto cantfind_ext2; 700 701 /* Set defaults before we parse the mount options */ 702 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 703 if (def_mount_opts & EXT2_DEFM_DEBUG) 704 set_opt(sbi->s_mount_opt, DEBUG); 705 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 706 set_opt(sbi->s_mount_opt, GRPID); 707 if (def_mount_opts & EXT2_DEFM_UID16) 708 set_opt(sbi->s_mount_opt, NO_UID32); 709 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 710 set_opt(sbi->s_mount_opt, XATTR_USER); 711 if (def_mount_opts & EXT2_DEFM_ACL) 712 set_opt(sbi->s_mount_opt, POSIX_ACL); 713 714 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 715 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 716 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO) 717 set_opt(sbi->s_mount_opt, ERRORS_RO); 718 719 sbi->s_resuid = le16_to_cpu(es->s_def_resuid); 720 sbi->s_resgid = le16_to_cpu(es->s_def_resgid); 721 722 if (!parse_options ((char *) data, sbi)) 723 goto failed_mount; 724 725 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 726 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 727 MS_POSIXACL : 0); 728 729 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 730 EXT2_MOUNT_XIP if not */ 731 732 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 733 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 734 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 735 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 736 printk("EXT2-fs warning: feature flags set on rev 0 fs, " 737 "running e2fsck is recommended\n"); 738 /* 739 * Check feature flags regardless of the revision level, since we 740 * previously didn't change the revision level when setting the flags, 741 * so there is a chance incompat flags are set on a rev 0 filesystem. 742 */ 743 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 744 if (features) { 745 printk("EXT2-fs: %s: couldn't mount because of " 746 "unsupported optional features (%x).\n", 747 sb->s_id, le32_to_cpu(features)); 748 goto failed_mount; 749 } 750 if (!(sb->s_flags & MS_RDONLY) && 751 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 752 printk("EXT2-fs: %s: couldn't mount RDWR because of " 753 "unsupported optional features (%x).\n", 754 sb->s_id, le32_to_cpu(features)); 755 goto failed_mount; 756 } 757 758 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 759 760 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) || 761 (sb->s_blocksize != blocksize))) { 762 if (!silent) 763 printk("XIP: Unsupported blocksize\n"); 764 goto failed_mount; 765 } 766 767 /* If the blocksize doesn't match, re-read the thing.. */ 768 if (sb->s_blocksize != blocksize) { 769 brelse(bh); 770 771 if (!sb_set_blocksize(sb, blocksize)) { 772 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); 773 goto failed_sbi; 774 } 775 776 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 777 offset = (sb_block*BLOCK_SIZE) % blocksize; 778 bh = sb_bread(sb, logic_sb_block); 779 if(!bh) { 780 printk("EXT2-fs: Couldn't read superblock on " 781 "2nd try.\n"); 782 goto failed_sbi; 783 } 784 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 785 sbi->s_es = es; 786 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 787 printk ("EXT2-fs: Magic mismatch, very weird !\n"); 788 goto failed_mount; 789 } 790 } 791 792 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 793 794 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 795 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 796 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 797 } else { 798 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 799 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 800 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 801 (sbi->s_inode_size & (sbi->s_inode_size - 1)) || 802 (sbi->s_inode_size > blocksize)) { 803 printk ("EXT2-fs: unsupported inode size: %d\n", 804 sbi->s_inode_size); 805 goto failed_mount; 806 } 807 } 808 809 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 810 le32_to_cpu(es->s_log_frag_size); 811 if (sbi->s_frag_size == 0) 812 goto cantfind_ext2; 813 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 814 815 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 816 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 817 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 818 819 if (EXT2_INODE_SIZE(sb) == 0) 820 goto cantfind_ext2; 821 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 822 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 823 goto cantfind_ext2; 824 sbi->s_itb_per_group = sbi->s_inodes_per_group / 825 sbi->s_inodes_per_block; 826 sbi->s_desc_per_block = sb->s_blocksize / 827 sizeof (struct ext2_group_desc); 828 sbi->s_sbh = bh; 829 sbi->s_mount_state = le16_to_cpu(es->s_state); 830 sbi->s_addr_per_block_bits = 831 log2 (EXT2_ADDR_PER_BLOCK(sb)); 832 sbi->s_desc_per_block_bits = 833 log2 (EXT2_DESC_PER_BLOCK(sb)); 834 835 if (sb->s_magic != EXT2_SUPER_MAGIC) 836 goto cantfind_ext2; 837 838 if (sb->s_blocksize != bh->b_size) { 839 if (!silent) 840 printk ("VFS: Unsupported blocksize on dev " 841 "%s.\n", sb->s_id); 842 goto failed_mount; 843 } 844 845 if (sb->s_blocksize != sbi->s_frag_size) { 846 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n", 847 sbi->s_frag_size, sb->s_blocksize); 848 goto failed_mount; 849 } 850 851 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 852 printk ("EXT2-fs: #blocks per group too big: %lu\n", 853 sbi->s_blocks_per_group); 854 goto failed_mount; 855 } 856 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 857 printk ("EXT2-fs: #fragments per group too big: %lu\n", 858 sbi->s_frags_per_group); 859 goto failed_mount; 860 } 861 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 862 printk ("EXT2-fs: #inodes per group too big: %lu\n", 863 sbi->s_inodes_per_group); 864 goto failed_mount; 865 } 866 867 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 868 goto cantfind_ext2; 869 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 870 le32_to_cpu(es->s_first_data_block) - 1) 871 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 872 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 873 EXT2_DESC_PER_BLOCK(sb); 874 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 875 if (sbi->s_group_desc == NULL) { 876 printk ("EXT2-fs: not enough memory\n"); 877 goto failed_mount; 878 } 879 bgl_lock_init(&sbi->s_blockgroup_lock); 880 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts), 881 GFP_KERNEL); 882 if (!sbi->s_debts) { 883 printk ("EXT2-fs: not enough memory\n"); 884 goto failed_mount_group_desc; 885 } 886 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts)); 887 for (i = 0; i < db_count; i++) { 888 block = descriptor_loc(sb, logic_sb_block, i); 889 sbi->s_group_desc[i] = sb_bread(sb, block); 890 if (!sbi->s_group_desc[i]) { 891 for (j = 0; j < i; j++) 892 brelse (sbi->s_group_desc[j]); 893 printk ("EXT2-fs: unable to read group descriptors\n"); 894 goto failed_mount_group_desc; 895 } 896 } 897 if (!ext2_check_descriptors (sb)) { 898 printk ("EXT2-fs: group descriptors corrupted!\n"); 899 goto failed_mount2; 900 } 901 sbi->s_gdb_count = db_count; 902 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 903 spin_lock_init(&sbi->s_next_gen_lock); 904 905 percpu_counter_init(&sbi->s_freeblocks_counter, 906 ext2_count_free_blocks(sb)); 907 percpu_counter_init(&sbi->s_freeinodes_counter, 908 ext2_count_free_inodes(sb)); 909 percpu_counter_init(&sbi->s_dirs_counter, 910 ext2_count_dirs(sb)); 911 /* 912 * set up enough so that it can read an inode 913 */ 914 sb->s_op = &ext2_sops; 915 sb->s_export_op = &ext2_export_ops; 916 sb->s_xattr = ext2_xattr_handlers; 917 root = iget(sb, EXT2_ROOT_INO); 918 sb->s_root = d_alloc_root(root); 919 if (!sb->s_root) { 920 iput(root); 921 printk(KERN_ERR "EXT2-fs: get root inode failed\n"); 922 goto failed_mount3; 923 } 924 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 925 dput(sb->s_root); 926 sb->s_root = NULL; 927 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n"); 928 goto failed_mount3; 929 } 930 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 931 ext2_warning(sb, __FUNCTION__, 932 "mounting ext3 filesystem as ext2"); 933 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); 934 return 0; 935 936 cantfind_ext2: 937 if (!silent) 938 printk("VFS: Can't find an ext2 filesystem on dev %s.\n", 939 sb->s_id); 940 goto failed_mount; 941 failed_mount3: 942 percpu_counter_destroy(&sbi->s_freeblocks_counter); 943 percpu_counter_destroy(&sbi->s_freeinodes_counter); 944 percpu_counter_destroy(&sbi->s_dirs_counter); 945 failed_mount2: 946 for (i = 0; i < db_count; i++) 947 brelse(sbi->s_group_desc[i]); 948 failed_mount_group_desc: 949 kfree(sbi->s_group_desc); 950 kfree(sbi->s_debts); 951 failed_mount: 952 brelse(bh); 953 failed_sbi: 954 sb->s_fs_info = NULL; 955 kfree(sbi); 956 return -EINVAL; 957 } 958 959 static void ext2_commit_super (struct super_block * sb, 960 struct ext2_super_block * es) 961 { 962 es->s_wtime = cpu_to_le32(get_seconds()); 963 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 964 sb->s_dirt = 0; 965 } 966 967 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) 968 { 969 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 970 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 971 es->s_wtime = cpu_to_le32(get_seconds()); 972 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 973 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 974 sb->s_dirt = 0; 975 } 976 977 /* 978 * In the second extended file system, it is not necessary to 979 * write the super block since we use a mapping of the 980 * disk super block in a buffer. 981 * 982 * However, this function is still used to set the fs valid 983 * flags to 0. We need to set this flag to 0 since the fs 984 * may have been checked while mounted and e2fsck may have 985 * set s_state to EXT2_VALID_FS after some corrections. 986 */ 987 988 void ext2_write_super (struct super_block * sb) 989 { 990 struct ext2_super_block * es; 991 lock_kernel(); 992 if (!(sb->s_flags & MS_RDONLY)) { 993 es = EXT2_SB(sb)->s_es; 994 995 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) { 996 ext2_debug ("setting valid to 0\n"); 997 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & 998 ~EXT2_VALID_FS); 999 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1000 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1001 es->s_mtime = cpu_to_le32(get_seconds()); 1002 ext2_sync_super(sb, es); 1003 } else 1004 ext2_commit_super (sb, es); 1005 } 1006 sb->s_dirt = 0; 1007 unlock_kernel(); 1008 } 1009 1010 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1011 { 1012 struct ext2_sb_info * sbi = EXT2_SB(sb); 1013 struct ext2_super_block * es; 1014 unsigned long old_mount_opt = sbi->s_mount_opt; 1015 struct ext2_mount_options old_opts; 1016 unsigned long old_sb_flags; 1017 int err; 1018 1019 /* Store the old options */ 1020 old_sb_flags = sb->s_flags; 1021 old_opts.s_mount_opt = sbi->s_mount_opt; 1022 old_opts.s_resuid = sbi->s_resuid; 1023 old_opts.s_resgid = sbi->s_resgid; 1024 1025 /* 1026 * Allow the "check" option to be passed as a remount option. 1027 */ 1028 if (!parse_options (data, sbi)) { 1029 err = -EINVAL; 1030 goto restore_opts; 1031 } 1032 1033 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1034 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1035 1036 es = sbi->s_es; 1037 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) != 1038 (old_mount_opt & EXT2_MOUNT_XIP)) && 1039 invalidate_inodes(sb)) 1040 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\ 1041 "xip remain in cache (no functional problem)"); 1042 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 1043 return 0; 1044 if (*flags & MS_RDONLY) { 1045 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1046 !(sbi->s_mount_state & EXT2_VALID_FS)) 1047 return 0; 1048 /* 1049 * OK, we are remounting a valid rw partition rdonly, so set 1050 * the rdonly flag and then mark the partition as valid again. 1051 */ 1052 es->s_state = cpu_to_le16(sbi->s_mount_state); 1053 es->s_mtime = cpu_to_le32(get_seconds()); 1054 } else { 1055 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1056 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1057 if (ret) { 1058 printk("EXT2-fs: %s: couldn't remount RDWR because of " 1059 "unsupported optional features (%x).\n", 1060 sb->s_id, le32_to_cpu(ret)); 1061 err = -EROFS; 1062 goto restore_opts; 1063 } 1064 /* 1065 * Mounting a RDONLY partition read-write, so reread and 1066 * store the current valid flag. (It may have been changed 1067 * by e2fsck since we originally mounted the partition.) 1068 */ 1069 sbi->s_mount_state = le16_to_cpu(es->s_state); 1070 if (!ext2_setup_super (sb, es, 0)) 1071 sb->s_flags &= ~MS_RDONLY; 1072 } 1073 ext2_sync_super(sb, es); 1074 return 0; 1075 restore_opts: 1076 sbi->s_mount_opt = old_opts.s_mount_opt; 1077 sbi->s_resuid = old_opts.s_resuid; 1078 sbi->s_resgid = old_opts.s_resgid; 1079 sb->s_flags = old_sb_flags; 1080 return err; 1081 } 1082 1083 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1084 { 1085 struct super_block *sb = dentry->d_sb; 1086 struct ext2_sb_info *sbi = EXT2_SB(sb); 1087 unsigned long overhead; 1088 int i; 1089 1090 if (test_opt (sb, MINIX_DF)) 1091 overhead = 0; 1092 else { 1093 /* 1094 * Compute the overhead (FS structures) 1095 */ 1096 1097 /* 1098 * All of the blocks before first_data_block are 1099 * overhead 1100 */ 1101 overhead = le32_to_cpu(sbi->s_es->s_first_data_block); 1102 1103 /* 1104 * Add the overhead attributed to the superblock and 1105 * block group descriptors. If the sparse superblocks 1106 * feature is turned on, then not all groups have this. 1107 */ 1108 for (i = 0; i < sbi->s_groups_count; i++) 1109 overhead += ext2_bg_has_super(sb, i) + 1110 ext2_bg_num_gdb(sb, i); 1111 1112 /* 1113 * Every block group has an inode bitmap, a block 1114 * bitmap, and an inode table. 1115 */ 1116 overhead += (sbi->s_groups_count * 1117 (2 + sbi->s_itb_per_group)); 1118 } 1119 1120 buf->f_type = EXT2_SUPER_MAGIC; 1121 buf->f_bsize = sb->s_blocksize; 1122 buf->f_blocks = le32_to_cpu(sbi->s_es->s_blocks_count) - overhead; 1123 buf->f_bfree = ext2_count_free_blocks(sb); 1124 buf->f_bavail = buf->f_bfree - le32_to_cpu(sbi->s_es->s_r_blocks_count); 1125 if (buf->f_bfree < le32_to_cpu(sbi->s_es->s_r_blocks_count)) 1126 buf->f_bavail = 0; 1127 buf->f_files = le32_to_cpu(sbi->s_es->s_inodes_count); 1128 buf->f_ffree = ext2_count_free_inodes (sb); 1129 buf->f_namelen = EXT2_NAME_LEN; 1130 return 0; 1131 } 1132 1133 static int ext2_get_sb(struct file_system_type *fs_type, 1134 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 1135 { 1136 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt); 1137 } 1138 1139 #ifdef CONFIG_QUOTA 1140 1141 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1142 * acquiring the locks... As quota files are never truncated and quota code 1143 * itself serializes the operations (and noone else should touch the files) 1144 * we don't have to be afraid of races */ 1145 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1146 size_t len, loff_t off) 1147 { 1148 struct inode *inode = sb_dqopt(sb)->files[type]; 1149 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1150 int err = 0; 1151 int offset = off & (sb->s_blocksize - 1); 1152 int tocopy; 1153 size_t toread; 1154 struct buffer_head tmp_bh; 1155 struct buffer_head *bh; 1156 loff_t i_size = i_size_read(inode); 1157 1158 if (off > i_size) 1159 return 0; 1160 if (off+len > i_size) 1161 len = i_size-off; 1162 toread = len; 1163 while (toread > 0) { 1164 tocopy = sb->s_blocksize - offset < toread ? 1165 sb->s_blocksize - offset : toread; 1166 1167 tmp_bh.b_state = 0; 1168 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1169 if (err) 1170 return err; 1171 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1172 memset(data, 0, tocopy); 1173 else { 1174 bh = sb_bread(sb, tmp_bh.b_blocknr); 1175 if (!bh) 1176 return -EIO; 1177 memcpy(data, bh->b_data+offset, tocopy); 1178 brelse(bh); 1179 } 1180 offset = 0; 1181 toread -= tocopy; 1182 data += tocopy; 1183 blk++; 1184 } 1185 return len; 1186 } 1187 1188 /* Write to quotafile */ 1189 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1190 const char *data, size_t len, loff_t off) 1191 { 1192 struct inode *inode = sb_dqopt(sb)->files[type]; 1193 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1194 int err = 0; 1195 int offset = off & (sb->s_blocksize - 1); 1196 int tocopy; 1197 size_t towrite = len; 1198 struct buffer_head tmp_bh; 1199 struct buffer_head *bh; 1200 1201 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 1202 while (towrite > 0) { 1203 tocopy = sb->s_blocksize - offset < towrite ? 1204 sb->s_blocksize - offset : towrite; 1205 1206 tmp_bh.b_state = 0; 1207 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1208 if (err) 1209 goto out; 1210 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1211 bh = sb_bread(sb, tmp_bh.b_blocknr); 1212 else 1213 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1214 if (!bh) { 1215 err = -EIO; 1216 goto out; 1217 } 1218 lock_buffer(bh); 1219 memcpy(bh->b_data+offset, data, tocopy); 1220 flush_dcache_page(bh->b_page); 1221 set_buffer_uptodate(bh); 1222 mark_buffer_dirty(bh); 1223 unlock_buffer(bh); 1224 brelse(bh); 1225 offset = 0; 1226 towrite -= tocopy; 1227 data += tocopy; 1228 blk++; 1229 } 1230 out: 1231 if (len == towrite) 1232 return err; 1233 if (inode->i_size < off+len-towrite) 1234 i_size_write(inode, off+len-towrite); 1235 inode->i_version++; 1236 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1237 mark_inode_dirty(inode); 1238 mutex_unlock(&inode->i_mutex); 1239 return len - towrite; 1240 } 1241 1242 #endif 1243 1244 static struct file_system_type ext2_fs_type = { 1245 .owner = THIS_MODULE, 1246 .name = "ext2", 1247 .get_sb = ext2_get_sb, 1248 .kill_sb = kill_block_super, 1249 .fs_flags = FS_REQUIRES_DEV, 1250 }; 1251 1252 static int __init init_ext2_fs(void) 1253 { 1254 int err = init_ext2_xattr(); 1255 if (err) 1256 return err; 1257 err = init_inodecache(); 1258 if (err) 1259 goto out1; 1260 err = register_filesystem(&ext2_fs_type); 1261 if (err) 1262 goto out; 1263 return 0; 1264 out: 1265 destroy_inodecache(); 1266 out1: 1267 exit_ext2_xattr(); 1268 return err; 1269 } 1270 1271 static void __exit exit_ext2_fs(void) 1272 { 1273 unregister_filesystem(&ext2_fs_type); 1274 destroy_inodecache(); 1275 exit_ext2_xattr(); 1276 } 1277 1278 module_init(init_ext2_fs) 1279 module_exit(exit_ext2_fs) 1280