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 if (kmem_cache_destroy(ext2_inode_cachep)) 188 printk(KERN_INFO "ext2_inode_cache: not all structures were freed\n"); 189 } 190 191 static void ext2_clear_inode(struct inode *inode) 192 { 193 #ifdef CONFIG_EXT2_FS_POSIX_ACL 194 struct ext2_inode_info *ei = EXT2_I(inode); 195 196 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) { 197 posix_acl_release(ei->i_acl); 198 ei->i_acl = EXT2_ACL_NOT_CACHED; 199 } 200 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) { 201 posix_acl_release(ei->i_default_acl); 202 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 203 } 204 #endif 205 } 206 207 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs) 208 { 209 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb); 210 211 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID) 212 seq_puts(seq, ",grpid"); 213 214 #if defined(CONFIG_QUOTA) 215 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 216 seq_puts(seq, ",usrquota"); 217 218 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 219 seq_puts(seq, ",grpquota"); 220 #endif 221 222 #if defined(CONFIG_EXT2_FS_XIP) 223 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 224 seq_puts(seq, ",xip"); 225 #endif 226 227 return 0; 228 } 229 230 #ifdef CONFIG_QUOTA 231 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 232 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 233 #endif 234 235 static struct super_operations ext2_sops = { 236 .alloc_inode = ext2_alloc_inode, 237 .destroy_inode = ext2_destroy_inode, 238 .read_inode = ext2_read_inode, 239 .write_inode = ext2_write_inode, 240 .put_inode = ext2_put_inode, 241 .delete_inode = ext2_delete_inode, 242 .put_super = ext2_put_super, 243 .write_super = ext2_write_super, 244 .statfs = ext2_statfs, 245 .remount_fs = ext2_remount, 246 .clear_inode = ext2_clear_inode, 247 .show_options = ext2_show_options, 248 #ifdef CONFIG_QUOTA 249 .quota_read = ext2_quota_read, 250 .quota_write = ext2_quota_write, 251 #endif 252 }; 253 254 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp) 255 { 256 __u32 *objp = vobjp; 257 unsigned long ino = objp[0]; 258 __u32 generation = objp[1]; 259 struct inode *inode; 260 struct dentry *result; 261 262 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 263 return ERR_PTR(-ESTALE); 264 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 265 return ERR_PTR(-ESTALE); 266 267 /* iget isn't really right if the inode is currently unallocated!! 268 * ext2_read_inode currently does appropriate checks, but 269 * it might be "neater" to call ext2_get_inode first and check 270 * if the inode is valid..... 271 */ 272 inode = iget(sb, ino); 273 if (inode == NULL) 274 return ERR_PTR(-ENOMEM); 275 if (is_bad_inode(inode) || 276 (generation && inode->i_generation != generation)) { 277 /* we didn't find the right inode.. */ 278 iput(inode); 279 return ERR_PTR(-ESTALE); 280 } 281 /* now to find a dentry. 282 * If possible, get a well-connected one 283 */ 284 result = d_alloc_anon(inode); 285 if (!result) { 286 iput(inode); 287 return ERR_PTR(-ENOMEM); 288 } 289 return result; 290 } 291 292 /* Yes, most of these are left as NULL!! 293 * A NULL value implies the default, which works with ext2-like file 294 * systems, but can be improved upon. 295 * Currently only get_parent is required. 296 */ 297 static struct export_operations ext2_export_ops = { 298 .get_parent = ext2_get_parent, 299 .get_dentry = ext2_get_dentry, 300 }; 301 302 static unsigned long get_sb_block(void **data) 303 { 304 unsigned long sb_block; 305 char *options = (char *) *data; 306 307 if (!options || strncmp(options, "sb=", 3) != 0) 308 return 1; /* Default location */ 309 options += 3; 310 sb_block = simple_strtoul(options, &options, 0); 311 if (*options && *options != ',') { 312 printk("EXT2-fs: Invalid sb specification: %s\n", 313 (char *) *data); 314 return 1; 315 } 316 if (*options == ',') 317 options++; 318 *data = (void *) options; 319 return sb_block; 320 } 321 322 enum { 323 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 324 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 325 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 326 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 327 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, 328 Opt_usrquota, Opt_grpquota 329 }; 330 331 static match_table_t tokens = { 332 {Opt_bsd_df, "bsddf"}, 333 {Opt_minix_df, "minixdf"}, 334 {Opt_grpid, "grpid"}, 335 {Opt_grpid, "bsdgroups"}, 336 {Opt_nogrpid, "nogrpid"}, 337 {Opt_nogrpid, "sysvgroups"}, 338 {Opt_resgid, "resgid=%u"}, 339 {Opt_resuid, "resuid=%u"}, 340 {Opt_sb, "sb=%u"}, 341 {Opt_err_cont, "errors=continue"}, 342 {Opt_err_panic, "errors=panic"}, 343 {Opt_err_ro, "errors=remount-ro"}, 344 {Opt_nouid32, "nouid32"}, 345 {Opt_nocheck, "check=none"}, 346 {Opt_nocheck, "nocheck"}, 347 {Opt_debug, "debug"}, 348 {Opt_oldalloc, "oldalloc"}, 349 {Opt_orlov, "orlov"}, 350 {Opt_nobh, "nobh"}, 351 {Opt_user_xattr, "user_xattr"}, 352 {Opt_nouser_xattr, "nouser_xattr"}, 353 {Opt_acl, "acl"}, 354 {Opt_noacl, "noacl"}, 355 {Opt_xip, "xip"}, 356 {Opt_grpquota, "grpquota"}, 357 {Opt_ignore, "noquota"}, 358 {Opt_quota, "quota"}, 359 {Opt_usrquota, "usrquota"}, 360 {Opt_err, NULL} 361 }; 362 363 static int parse_options (char * options, 364 struct ext2_sb_info *sbi) 365 { 366 char * p; 367 substring_t args[MAX_OPT_ARGS]; 368 unsigned long kind = EXT2_MOUNT_ERRORS_CONT; 369 int option; 370 371 if (!options) 372 return 1; 373 374 while ((p = strsep (&options, ",")) != NULL) { 375 int token; 376 if (!*p) 377 continue; 378 379 token = match_token(p, tokens, args); 380 switch (token) { 381 case Opt_bsd_df: 382 clear_opt (sbi->s_mount_opt, MINIX_DF); 383 break; 384 case Opt_minix_df: 385 set_opt (sbi->s_mount_opt, MINIX_DF); 386 break; 387 case Opt_grpid: 388 set_opt (sbi->s_mount_opt, GRPID); 389 break; 390 case Opt_nogrpid: 391 clear_opt (sbi->s_mount_opt, GRPID); 392 break; 393 case Opt_resuid: 394 if (match_int(&args[0], &option)) 395 return 0; 396 sbi->s_resuid = option; 397 break; 398 case Opt_resgid: 399 if (match_int(&args[0], &option)) 400 return 0; 401 sbi->s_resgid = option; 402 break; 403 case Opt_sb: 404 /* handled by get_sb_block() instead of here */ 405 /* *sb_block = match_int(&args[0]); */ 406 break; 407 case Opt_err_panic: 408 kind = EXT2_MOUNT_ERRORS_PANIC; 409 break; 410 case Opt_err_ro: 411 kind = EXT2_MOUNT_ERRORS_RO; 412 break; 413 case Opt_err_cont: 414 kind = EXT2_MOUNT_ERRORS_CONT; 415 break; 416 case Opt_nouid32: 417 set_opt (sbi->s_mount_opt, NO_UID32); 418 break; 419 case Opt_nocheck: 420 clear_opt (sbi->s_mount_opt, CHECK); 421 break; 422 case Opt_debug: 423 set_opt (sbi->s_mount_opt, DEBUG); 424 break; 425 case Opt_oldalloc: 426 set_opt (sbi->s_mount_opt, OLDALLOC); 427 break; 428 case Opt_orlov: 429 clear_opt (sbi->s_mount_opt, OLDALLOC); 430 break; 431 case Opt_nobh: 432 set_opt (sbi->s_mount_opt, NOBH); 433 break; 434 #ifdef CONFIG_EXT2_FS_XATTR 435 case Opt_user_xattr: 436 set_opt (sbi->s_mount_opt, XATTR_USER); 437 break; 438 case Opt_nouser_xattr: 439 clear_opt (sbi->s_mount_opt, XATTR_USER); 440 break; 441 #else 442 case Opt_user_xattr: 443 case Opt_nouser_xattr: 444 printk("EXT2 (no)user_xattr options not supported\n"); 445 break; 446 #endif 447 #ifdef CONFIG_EXT2_FS_POSIX_ACL 448 case Opt_acl: 449 set_opt(sbi->s_mount_opt, POSIX_ACL); 450 break; 451 case Opt_noacl: 452 clear_opt(sbi->s_mount_opt, POSIX_ACL); 453 break; 454 #else 455 case Opt_acl: 456 case Opt_noacl: 457 printk("EXT2 (no)acl options not supported\n"); 458 break; 459 #endif 460 case Opt_xip: 461 #ifdef CONFIG_EXT2_FS_XIP 462 set_opt (sbi->s_mount_opt, XIP); 463 #else 464 printk("EXT2 xip option not supported\n"); 465 #endif 466 break; 467 468 #if defined(CONFIG_QUOTA) 469 case Opt_quota: 470 case Opt_usrquota: 471 set_opt(sbi->s_mount_opt, USRQUOTA); 472 break; 473 474 case Opt_grpquota: 475 set_opt(sbi->s_mount_opt, GRPQUOTA); 476 break; 477 #else 478 case Opt_quota: 479 case Opt_usrquota: 480 case Opt_grpquota: 481 printk(KERN_ERR 482 "EXT2-fs: quota operations not supported.\n"); 483 484 break; 485 #endif 486 487 case Opt_ignore: 488 break; 489 default: 490 return 0; 491 } 492 } 493 sbi->s_mount_opt |= kind; 494 return 1; 495 } 496 497 static int ext2_setup_super (struct super_block * sb, 498 struct ext2_super_block * es, 499 int read_only) 500 { 501 int res = 0; 502 struct ext2_sb_info *sbi = EXT2_SB(sb); 503 504 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 505 printk ("EXT2-fs warning: revision level too high, " 506 "forcing read-only mode\n"); 507 res = MS_RDONLY; 508 } 509 if (read_only) 510 return res; 511 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 512 printk ("EXT2-fs warning: mounting unchecked fs, " 513 "running e2fsck is recommended\n"); 514 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 515 printk ("EXT2-fs warning: mounting fs with errors, " 516 "running e2fsck is recommended\n"); 517 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 518 le16_to_cpu(es->s_mnt_count) >= 519 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 520 printk ("EXT2-fs warning: maximal mount count reached, " 521 "running e2fsck is recommended\n"); 522 else if (le32_to_cpu(es->s_checkinterval) && 523 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds())) 524 printk ("EXT2-fs warning: checktime reached, " 525 "running e2fsck is recommended\n"); 526 if (!le16_to_cpu(es->s_max_mnt_count)) 527 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 528 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1); 529 ext2_write_super(sb); 530 if (test_opt (sb, DEBUG)) 531 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, " 532 "bpg=%lu, ipg=%lu, mo=%04lx]\n", 533 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 534 sbi->s_frag_size, 535 sbi->s_groups_count, 536 EXT2_BLOCKS_PER_GROUP(sb), 537 EXT2_INODES_PER_GROUP(sb), 538 sbi->s_mount_opt); 539 return res; 540 } 541 542 static int ext2_check_descriptors (struct super_block * sb) 543 { 544 int i; 545 int desc_block = 0; 546 struct ext2_sb_info *sbi = EXT2_SB(sb); 547 unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block); 548 unsigned long last_block; 549 struct ext2_group_desc * gdp = NULL; 550 551 ext2_debug ("Checking group descriptors"); 552 553 for (i = 0; i < sbi->s_groups_count; i++) 554 { 555 if (i == sbi->s_groups_count - 1) 556 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 557 else 558 last_block = first_block + 559 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 560 561 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0) 562 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data; 563 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 564 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 565 { 566 ext2_error (sb, "ext2_check_descriptors", 567 "Block bitmap for group %d" 568 " not in group (block %lu)!", 569 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 570 return 0; 571 } 572 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 573 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 574 { 575 ext2_error (sb, "ext2_check_descriptors", 576 "Inode bitmap for group %d" 577 " not in group (block %lu)!", 578 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 579 return 0; 580 } 581 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 582 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group > 583 last_block) 584 { 585 ext2_error (sb, "ext2_check_descriptors", 586 "Inode table for group %d" 587 " not in group (block %lu)!", 588 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 589 return 0; 590 } 591 first_block += EXT2_BLOCKS_PER_GROUP(sb); 592 gdp++; 593 } 594 return 1; 595 } 596 597 #define log2(n) ffz(~(n)) 598 599 /* 600 * Maximal file size. There is a direct, and {,double-,triple-}indirect 601 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 602 * We need to be 1 filesystem block less than the 2^32 sector limit. 603 */ 604 static loff_t ext2_max_size(int bits) 605 { 606 loff_t res = EXT2_NDIR_BLOCKS; 607 /* This constant is calculated to be the largest file size for a 608 * dense, 4k-blocksize file such that the total number of 609 * sectors in the file, including data and all indirect blocks, 610 * does not exceed 2^32. */ 611 const loff_t upper_limit = 0x1ff7fffd000LL; 612 613 res += 1LL << (bits-2); 614 res += 1LL << (2*(bits-2)); 615 res += 1LL << (3*(bits-2)); 616 res <<= bits; 617 if (res > upper_limit) 618 res = upper_limit; 619 return res; 620 } 621 622 static unsigned long descriptor_loc(struct super_block *sb, 623 unsigned long logic_sb_block, 624 int nr) 625 { 626 struct ext2_sb_info *sbi = EXT2_SB(sb); 627 unsigned long bg, first_data_block, first_meta_bg; 628 int has_super = 0; 629 630 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block); 631 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 632 633 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 634 nr < first_meta_bg) 635 return (logic_sb_block + nr + 1); 636 bg = sbi->s_desc_per_block * nr; 637 if (ext2_bg_has_super(sb, bg)) 638 has_super = 1; 639 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group)); 640 } 641 642 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 643 { 644 struct buffer_head * bh; 645 struct ext2_sb_info * sbi; 646 struct ext2_super_block * es; 647 struct inode *root; 648 unsigned long block; 649 unsigned long sb_block = get_sb_block(&data); 650 unsigned long logic_sb_block; 651 unsigned long offset = 0; 652 unsigned long def_mount_opts; 653 int blocksize = BLOCK_SIZE; 654 int db_count; 655 int i, j; 656 __le32 features; 657 658 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 659 if (!sbi) 660 return -ENOMEM; 661 sb->s_fs_info = sbi; 662 663 /* 664 * See what the current blocksize for the device is, and 665 * use that as the blocksize. Otherwise (or if the blocksize 666 * is smaller than the default) use the default. 667 * This is important for devices that have a hardware 668 * sectorsize that is larger than the default. 669 */ 670 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 671 if (!blocksize) { 672 printk ("EXT2-fs: unable to set blocksize\n"); 673 goto failed_sbi; 674 } 675 676 /* 677 * If the superblock doesn't start on a hardware sector boundary, 678 * calculate the offset. 679 */ 680 if (blocksize != BLOCK_SIZE) { 681 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 682 offset = (sb_block*BLOCK_SIZE) % blocksize; 683 } else { 684 logic_sb_block = sb_block; 685 } 686 687 if (!(bh = sb_bread(sb, logic_sb_block))) { 688 printk ("EXT2-fs: unable to read superblock\n"); 689 goto failed_sbi; 690 } 691 /* 692 * Note: s_es must be initialized as soon as possible because 693 * some ext2 macro-instructions depend on its value 694 */ 695 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 696 sbi->s_es = es; 697 sb->s_magic = le16_to_cpu(es->s_magic); 698 699 if (sb->s_magic != EXT2_SUPER_MAGIC) 700 goto cantfind_ext2; 701 702 /* Set defaults before we parse the mount options */ 703 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 704 if (def_mount_opts & EXT2_DEFM_DEBUG) 705 set_opt(sbi->s_mount_opt, DEBUG); 706 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 707 set_opt(sbi->s_mount_opt, GRPID); 708 if (def_mount_opts & EXT2_DEFM_UID16) 709 set_opt(sbi->s_mount_opt, NO_UID32); 710 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 711 set_opt(sbi->s_mount_opt, XATTR_USER); 712 if (def_mount_opts & EXT2_DEFM_ACL) 713 set_opt(sbi->s_mount_opt, POSIX_ACL); 714 715 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 716 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 717 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO) 718 set_opt(sbi->s_mount_opt, ERRORS_RO); 719 720 sbi->s_resuid = le16_to_cpu(es->s_def_resuid); 721 sbi->s_resgid = le16_to_cpu(es->s_def_resgid); 722 723 if (!parse_options ((char *) data, sbi)) 724 goto failed_mount; 725 726 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 727 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 728 MS_POSIXACL : 0); 729 730 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 731 EXT2_MOUNT_XIP if not */ 732 733 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 734 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 735 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 736 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 737 printk("EXT2-fs warning: feature flags set on rev 0 fs, " 738 "running e2fsck is recommended\n"); 739 /* 740 * Check feature flags regardless of the revision level, since we 741 * previously didn't change the revision level when setting the flags, 742 * so there is a chance incompat flags are set on a rev 0 filesystem. 743 */ 744 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 745 if (features) { 746 printk("EXT2-fs: %s: couldn't mount because of " 747 "unsupported optional features (%x).\n", 748 sb->s_id, le32_to_cpu(features)); 749 goto failed_mount; 750 } 751 if (!(sb->s_flags & MS_RDONLY) && 752 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 753 printk("EXT2-fs: %s: couldn't mount RDWR because of " 754 "unsupported optional features (%x).\n", 755 sb->s_id, le32_to_cpu(features)); 756 goto failed_mount; 757 } 758 759 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 760 761 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) || 762 (sb->s_blocksize != blocksize))) { 763 if (!silent) 764 printk("XIP: Unsupported blocksize\n"); 765 goto failed_mount; 766 } 767 768 /* If the blocksize doesn't match, re-read the thing.. */ 769 if (sb->s_blocksize != blocksize) { 770 brelse(bh); 771 772 if (!sb_set_blocksize(sb, blocksize)) { 773 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); 774 goto failed_sbi; 775 } 776 777 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 778 offset = (sb_block*BLOCK_SIZE) % blocksize; 779 bh = sb_bread(sb, logic_sb_block); 780 if(!bh) { 781 printk("EXT2-fs: Couldn't read superblock on " 782 "2nd try.\n"); 783 goto failed_sbi; 784 } 785 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 786 sbi->s_es = es; 787 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 788 printk ("EXT2-fs: Magic mismatch, very weird !\n"); 789 goto failed_mount; 790 } 791 } 792 793 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 794 795 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 796 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 797 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 798 } else { 799 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 800 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 801 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 802 (sbi->s_inode_size & (sbi->s_inode_size - 1)) || 803 (sbi->s_inode_size > blocksize)) { 804 printk ("EXT2-fs: unsupported inode size: %d\n", 805 sbi->s_inode_size); 806 goto failed_mount; 807 } 808 } 809 810 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 811 le32_to_cpu(es->s_log_frag_size); 812 if (sbi->s_frag_size == 0) 813 goto cantfind_ext2; 814 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 815 816 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 817 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 818 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 819 820 if (EXT2_INODE_SIZE(sb) == 0) 821 goto cantfind_ext2; 822 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 823 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 824 goto cantfind_ext2; 825 sbi->s_itb_per_group = sbi->s_inodes_per_group / 826 sbi->s_inodes_per_block; 827 sbi->s_desc_per_block = sb->s_blocksize / 828 sizeof (struct ext2_group_desc); 829 sbi->s_sbh = bh; 830 sbi->s_mount_state = le16_to_cpu(es->s_state); 831 sbi->s_addr_per_block_bits = 832 log2 (EXT2_ADDR_PER_BLOCK(sb)); 833 sbi->s_desc_per_block_bits = 834 log2 (EXT2_DESC_PER_BLOCK(sb)); 835 836 if (sb->s_magic != EXT2_SUPER_MAGIC) 837 goto cantfind_ext2; 838 839 if (sb->s_blocksize != bh->b_size) { 840 if (!silent) 841 printk ("VFS: Unsupported blocksize on dev " 842 "%s.\n", sb->s_id); 843 goto failed_mount; 844 } 845 846 if (sb->s_blocksize != sbi->s_frag_size) { 847 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n", 848 sbi->s_frag_size, sb->s_blocksize); 849 goto failed_mount; 850 } 851 852 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 853 printk ("EXT2-fs: #blocks per group too big: %lu\n", 854 sbi->s_blocks_per_group); 855 goto failed_mount; 856 } 857 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 858 printk ("EXT2-fs: #fragments per group too big: %lu\n", 859 sbi->s_frags_per_group); 860 goto failed_mount; 861 } 862 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 863 printk ("EXT2-fs: #inodes per group too big: %lu\n", 864 sbi->s_inodes_per_group); 865 goto failed_mount; 866 } 867 868 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 869 goto cantfind_ext2; 870 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 871 le32_to_cpu(es->s_first_data_block) - 1) 872 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 873 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 874 EXT2_DESC_PER_BLOCK(sb); 875 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 876 if (sbi->s_group_desc == NULL) { 877 printk ("EXT2-fs: not enough memory\n"); 878 goto failed_mount; 879 } 880 bgl_lock_init(&sbi->s_blockgroup_lock); 881 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts), 882 GFP_KERNEL); 883 if (!sbi->s_debts) { 884 printk ("EXT2-fs: not enough memory\n"); 885 goto failed_mount_group_desc; 886 } 887 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts)); 888 for (i = 0; i < db_count; i++) { 889 block = descriptor_loc(sb, logic_sb_block, i); 890 sbi->s_group_desc[i] = sb_bread(sb, block); 891 if (!sbi->s_group_desc[i]) { 892 for (j = 0; j < i; j++) 893 brelse (sbi->s_group_desc[j]); 894 printk ("EXT2-fs: unable to read group descriptors\n"); 895 goto failed_mount_group_desc; 896 } 897 } 898 if (!ext2_check_descriptors (sb)) { 899 printk ("EXT2-fs: group descriptors corrupted!\n"); 900 goto failed_mount2; 901 } 902 sbi->s_gdb_count = db_count; 903 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 904 spin_lock_init(&sbi->s_next_gen_lock); 905 906 percpu_counter_init(&sbi->s_freeblocks_counter, 907 ext2_count_free_blocks(sb)); 908 percpu_counter_init(&sbi->s_freeinodes_counter, 909 ext2_count_free_inodes(sb)); 910 percpu_counter_init(&sbi->s_dirs_counter, 911 ext2_count_dirs(sb)); 912 /* 913 * set up enough so that it can read an inode 914 */ 915 sb->s_op = &ext2_sops; 916 sb->s_export_op = &ext2_export_ops; 917 sb->s_xattr = ext2_xattr_handlers; 918 root = iget(sb, EXT2_ROOT_INO); 919 sb->s_root = d_alloc_root(root); 920 if (!sb->s_root) { 921 iput(root); 922 printk(KERN_ERR "EXT2-fs: get root inode failed\n"); 923 goto failed_mount3; 924 } 925 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 926 dput(sb->s_root); 927 sb->s_root = NULL; 928 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n"); 929 goto failed_mount3; 930 } 931 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 932 ext2_warning(sb, __FUNCTION__, 933 "mounting ext3 filesystem as ext2"); 934 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); 935 return 0; 936 937 cantfind_ext2: 938 if (!silent) 939 printk("VFS: Can't find an ext2 filesystem on dev %s.\n", 940 sb->s_id); 941 goto failed_mount; 942 failed_mount3: 943 percpu_counter_destroy(&sbi->s_freeblocks_counter); 944 percpu_counter_destroy(&sbi->s_freeinodes_counter); 945 percpu_counter_destroy(&sbi->s_dirs_counter); 946 failed_mount2: 947 for (i = 0; i < db_count; i++) 948 brelse(sbi->s_group_desc[i]); 949 failed_mount_group_desc: 950 kfree(sbi->s_group_desc); 951 kfree(sbi->s_debts); 952 failed_mount: 953 brelse(bh); 954 failed_sbi: 955 sb->s_fs_info = NULL; 956 kfree(sbi); 957 return -EINVAL; 958 } 959 960 static void ext2_commit_super (struct super_block * sb, 961 struct ext2_super_block * es) 962 { 963 es->s_wtime = cpu_to_le32(get_seconds()); 964 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 965 sb->s_dirt = 0; 966 } 967 968 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) 969 { 970 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 971 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 972 es->s_wtime = cpu_to_le32(get_seconds()); 973 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 974 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 975 sb->s_dirt = 0; 976 } 977 978 /* 979 * In the second extended file system, it is not necessary to 980 * write the super block since we use a mapping of the 981 * disk super block in a buffer. 982 * 983 * However, this function is still used to set the fs valid 984 * flags to 0. We need to set this flag to 0 since the fs 985 * may have been checked while mounted and e2fsck may have 986 * set s_state to EXT2_VALID_FS after some corrections. 987 */ 988 989 void ext2_write_super (struct super_block * sb) 990 { 991 struct ext2_super_block * es; 992 lock_kernel(); 993 if (!(sb->s_flags & MS_RDONLY)) { 994 es = EXT2_SB(sb)->s_es; 995 996 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) { 997 ext2_debug ("setting valid to 0\n"); 998 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & 999 ~EXT2_VALID_FS); 1000 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1001 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1002 es->s_mtime = cpu_to_le32(get_seconds()); 1003 ext2_sync_super(sb, es); 1004 } else 1005 ext2_commit_super (sb, es); 1006 } 1007 sb->s_dirt = 0; 1008 unlock_kernel(); 1009 } 1010 1011 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1012 { 1013 struct ext2_sb_info * sbi = EXT2_SB(sb); 1014 struct ext2_super_block * es; 1015 unsigned long old_mount_opt = sbi->s_mount_opt; 1016 struct ext2_mount_options old_opts; 1017 unsigned long old_sb_flags; 1018 int err; 1019 1020 /* Store the old options */ 1021 old_sb_flags = sb->s_flags; 1022 old_opts.s_mount_opt = sbi->s_mount_opt; 1023 old_opts.s_resuid = sbi->s_resuid; 1024 old_opts.s_resgid = sbi->s_resgid; 1025 1026 /* 1027 * Allow the "check" option to be passed as a remount option. 1028 */ 1029 if (!parse_options (data, sbi)) { 1030 err = -EINVAL; 1031 goto restore_opts; 1032 } 1033 1034 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1035 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1036 1037 es = sbi->s_es; 1038 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) != 1039 (old_mount_opt & EXT2_MOUNT_XIP)) && 1040 invalidate_inodes(sb)) 1041 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\ 1042 "xip remain in cache (no functional problem)"); 1043 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 1044 return 0; 1045 if (*flags & MS_RDONLY) { 1046 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1047 !(sbi->s_mount_state & EXT2_VALID_FS)) 1048 return 0; 1049 /* 1050 * OK, we are remounting a valid rw partition rdonly, so set 1051 * the rdonly flag and then mark the partition as valid again. 1052 */ 1053 es->s_state = cpu_to_le16(sbi->s_mount_state); 1054 es->s_mtime = cpu_to_le32(get_seconds()); 1055 } else { 1056 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1057 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1058 if (ret) { 1059 printk("EXT2-fs: %s: couldn't remount RDWR because of " 1060 "unsupported optional features (%x).\n", 1061 sb->s_id, le32_to_cpu(ret)); 1062 err = -EROFS; 1063 goto restore_opts; 1064 } 1065 /* 1066 * Mounting a RDONLY partition read-write, so reread and 1067 * store the current valid flag. (It may have been changed 1068 * by e2fsck since we originally mounted the partition.) 1069 */ 1070 sbi->s_mount_state = le16_to_cpu(es->s_state); 1071 if (!ext2_setup_super (sb, es, 0)) 1072 sb->s_flags &= ~MS_RDONLY; 1073 } 1074 ext2_sync_super(sb, es); 1075 return 0; 1076 restore_opts: 1077 sbi->s_mount_opt = old_opts.s_mount_opt; 1078 sbi->s_resuid = old_opts.s_resuid; 1079 sbi->s_resgid = old_opts.s_resgid; 1080 sb->s_flags = old_sb_flags; 1081 return err; 1082 } 1083 1084 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1085 { 1086 struct super_block *sb = dentry->d_sb; 1087 struct ext2_sb_info *sbi = EXT2_SB(sb); 1088 unsigned long overhead; 1089 int i; 1090 1091 if (test_opt (sb, MINIX_DF)) 1092 overhead = 0; 1093 else { 1094 /* 1095 * Compute the overhead (FS structures) 1096 */ 1097 1098 /* 1099 * All of the blocks before first_data_block are 1100 * overhead 1101 */ 1102 overhead = le32_to_cpu(sbi->s_es->s_first_data_block); 1103 1104 /* 1105 * Add the overhead attributed to the superblock and 1106 * block group descriptors. If the sparse superblocks 1107 * feature is turned on, then not all groups have this. 1108 */ 1109 for (i = 0; i < sbi->s_groups_count; i++) 1110 overhead += ext2_bg_has_super(sb, i) + 1111 ext2_bg_num_gdb(sb, i); 1112 1113 /* 1114 * Every block group has an inode bitmap, a block 1115 * bitmap, and an inode table. 1116 */ 1117 overhead += (sbi->s_groups_count * 1118 (2 + sbi->s_itb_per_group)); 1119 } 1120 1121 buf->f_type = EXT2_SUPER_MAGIC; 1122 buf->f_bsize = sb->s_blocksize; 1123 buf->f_blocks = le32_to_cpu(sbi->s_es->s_blocks_count) - overhead; 1124 buf->f_bfree = ext2_count_free_blocks(sb); 1125 buf->f_bavail = buf->f_bfree - le32_to_cpu(sbi->s_es->s_r_blocks_count); 1126 if (buf->f_bfree < le32_to_cpu(sbi->s_es->s_r_blocks_count)) 1127 buf->f_bavail = 0; 1128 buf->f_files = le32_to_cpu(sbi->s_es->s_inodes_count); 1129 buf->f_ffree = ext2_count_free_inodes (sb); 1130 buf->f_namelen = EXT2_NAME_LEN; 1131 return 0; 1132 } 1133 1134 static int ext2_get_sb(struct file_system_type *fs_type, 1135 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 1136 { 1137 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt); 1138 } 1139 1140 #ifdef CONFIG_QUOTA 1141 1142 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1143 * acquiring the locks... As quota files are never truncated and quota code 1144 * itself serializes the operations (and noone else should touch the files) 1145 * we don't have to be afraid of races */ 1146 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1147 size_t len, loff_t off) 1148 { 1149 struct inode *inode = sb_dqopt(sb)->files[type]; 1150 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1151 int err = 0; 1152 int offset = off & (sb->s_blocksize - 1); 1153 int tocopy; 1154 size_t toread; 1155 struct buffer_head tmp_bh; 1156 struct buffer_head *bh; 1157 loff_t i_size = i_size_read(inode); 1158 1159 if (off > i_size) 1160 return 0; 1161 if (off+len > i_size) 1162 len = i_size-off; 1163 toread = len; 1164 while (toread > 0) { 1165 tocopy = sb->s_blocksize - offset < toread ? 1166 sb->s_blocksize - offset : toread; 1167 1168 tmp_bh.b_state = 0; 1169 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1170 if (err) 1171 return err; 1172 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1173 memset(data, 0, tocopy); 1174 else { 1175 bh = sb_bread(sb, tmp_bh.b_blocknr); 1176 if (!bh) 1177 return -EIO; 1178 memcpy(data, bh->b_data+offset, tocopy); 1179 brelse(bh); 1180 } 1181 offset = 0; 1182 toread -= tocopy; 1183 data += tocopy; 1184 blk++; 1185 } 1186 return len; 1187 } 1188 1189 /* Write to quotafile */ 1190 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1191 const char *data, size_t len, loff_t off) 1192 { 1193 struct inode *inode = sb_dqopt(sb)->files[type]; 1194 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1195 int err = 0; 1196 int offset = off & (sb->s_blocksize - 1); 1197 int tocopy; 1198 size_t towrite = len; 1199 struct buffer_head tmp_bh; 1200 struct buffer_head *bh; 1201 1202 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 1203 while (towrite > 0) { 1204 tocopy = sb->s_blocksize - offset < towrite ? 1205 sb->s_blocksize - offset : towrite; 1206 1207 tmp_bh.b_state = 0; 1208 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1209 if (err) 1210 goto out; 1211 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1212 bh = sb_bread(sb, tmp_bh.b_blocknr); 1213 else 1214 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1215 if (!bh) { 1216 err = -EIO; 1217 goto out; 1218 } 1219 lock_buffer(bh); 1220 memcpy(bh->b_data+offset, data, tocopy); 1221 flush_dcache_page(bh->b_page); 1222 set_buffer_uptodate(bh); 1223 mark_buffer_dirty(bh); 1224 unlock_buffer(bh); 1225 brelse(bh); 1226 offset = 0; 1227 towrite -= tocopy; 1228 data += tocopy; 1229 blk++; 1230 } 1231 out: 1232 if (len == towrite) 1233 return err; 1234 if (inode->i_size < off+len-towrite) 1235 i_size_write(inode, off+len-towrite); 1236 inode->i_version++; 1237 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1238 mark_inode_dirty(inode); 1239 mutex_unlock(&inode->i_mutex); 1240 return len - towrite; 1241 } 1242 1243 #endif 1244 1245 static struct file_system_type ext2_fs_type = { 1246 .owner = THIS_MODULE, 1247 .name = "ext2", 1248 .get_sb = ext2_get_sb, 1249 .kill_sb = kill_block_super, 1250 .fs_flags = FS_REQUIRES_DEV, 1251 }; 1252 1253 static int __init init_ext2_fs(void) 1254 { 1255 int err = init_ext2_xattr(); 1256 if (err) 1257 return err; 1258 err = init_inodecache(); 1259 if (err) 1260 goto out1; 1261 err = register_filesystem(&ext2_fs_type); 1262 if (err) 1263 goto out; 1264 return 0; 1265 out: 1266 destroy_inodecache(); 1267 out1: 1268 exit_ext2_xattr(); 1269 return err; 1270 } 1271 1272 static void __exit exit_ext2_fs(void) 1273 { 1274 unregister_filesystem(&ext2_fs_type); 1275 destroy_inodecache(); 1276 exit_ext2_xattr(); 1277 } 1278 1279 module_init(init_ext2_fs) 1280 module_exit(exit_ext2_fs) 1281