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 struct kmem_cache * 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, GFP_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, struct kmem_cache * cachep, unsigned long flags) 160 { 161 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo; 162 163 if (flags & SLAB_CTOR_CONSTRUCTOR) { 164 rwlock_init(&ei->i_meta_lock); 165 #ifdef CONFIG_EXT2_FS_XATTR 166 init_rwsem(&ei->xattr_sem); 167 #endif 168 inode_init_once(&ei->vfs_inode); 169 } 170 } 171 172 static int init_inodecache(void) 173 { 174 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 175 sizeof(struct ext2_inode_info), 176 0, (SLAB_RECLAIM_ACCOUNT| 177 SLAB_MEM_SPREAD), 178 init_once, NULL); 179 if (ext2_inode_cachep == NULL) 180 return -ENOMEM; 181 return 0; 182 } 183 184 static void destroy_inodecache(void) 185 { 186 kmem_cache_destroy(ext2_inode_cachep); 187 } 188 189 static void ext2_clear_inode(struct inode *inode) 190 { 191 #ifdef CONFIG_EXT2_FS_POSIX_ACL 192 struct ext2_inode_info *ei = EXT2_I(inode); 193 194 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) { 195 posix_acl_release(ei->i_acl); 196 ei->i_acl = EXT2_ACL_NOT_CACHED; 197 } 198 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) { 199 posix_acl_release(ei->i_default_acl); 200 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 201 } 202 #endif 203 } 204 205 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs) 206 { 207 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb); 208 209 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID) 210 seq_puts(seq, ",grpid"); 211 212 #if defined(CONFIG_QUOTA) 213 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 214 seq_puts(seq, ",usrquota"); 215 216 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 217 seq_puts(seq, ",grpquota"); 218 #endif 219 220 #if defined(CONFIG_EXT2_FS_XIP) 221 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 222 seq_puts(seq, ",xip"); 223 #endif 224 225 return 0; 226 } 227 228 #ifdef CONFIG_QUOTA 229 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 230 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 231 #endif 232 233 static const struct super_operations ext2_sops = { 234 .alloc_inode = ext2_alloc_inode, 235 .destroy_inode = ext2_destroy_inode, 236 .read_inode = ext2_read_inode, 237 .write_inode = ext2_write_inode, 238 .put_inode = ext2_put_inode, 239 .delete_inode = ext2_delete_inode, 240 .put_super = ext2_put_super, 241 .write_super = ext2_write_super, 242 .statfs = ext2_statfs, 243 .remount_fs = ext2_remount, 244 .clear_inode = ext2_clear_inode, 245 .show_options = ext2_show_options, 246 #ifdef CONFIG_QUOTA 247 .quota_read = ext2_quota_read, 248 .quota_write = ext2_quota_write, 249 #endif 250 }; 251 252 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp) 253 { 254 __u32 *objp = vobjp; 255 unsigned long ino = objp[0]; 256 __u32 generation = objp[1]; 257 struct inode *inode; 258 struct dentry *result; 259 260 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 261 return ERR_PTR(-ESTALE); 262 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 263 return ERR_PTR(-ESTALE); 264 265 /* iget isn't really right if the inode is currently unallocated!! 266 * ext2_read_inode currently does appropriate checks, but 267 * it might be "neater" to call ext2_get_inode first and check 268 * if the inode is valid..... 269 */ 270 inode = iget(sb, ino); 271 if (inode == NULL) 272 return ERR_PTR(-ENOMEM); 273 if (is_bad_inode(inode) || 274 (generation && inode->i_generation != generation)) { 275 /* we didn't find the right inode.. */ 276 iput(inode); 277 return ERR_PTR(-ESTALE); 278 } 279 /* now to find a dentry. 280 * If possible, get a well-connected one 281 */ 282 result = d_alloc_anon(inode); 283 if (!result) { 284 iput(inode); 285 return ERR_PTR(-ENOMEM); 286 } 287 return result; 288 } 289 290 /* Yes, most of these are left as NULL!! 291 * A NULL value implies the default, which works with ext2-like file 292 * systems, but can be improved upon. 293 * Currently only get_parent is required. 294 */ 295 static struct export_operations ext2_export_ops = { 296 .get_parent = ext2_get_parent, 297 .get_dentry = ext2_get_dentry, 298 }; 299 300 static unsigned long get_sb_block(void **data) 301 { 302 unsigned long sb_block; 303 char *options = (char *) *data; 304 305 if (!options || strncmp(options, "sb=", 3) != 0) 306 return 1; /* Default location */ 307 options += 3; 308 sb_block = simple_strtoul(options, &options, 0); 309 if (*options && *options != ',') { 310 printk("EXT2-fs: Invalid sb specification: %s\n", 311 (char *) *data); 312 return 1; 313 } 314 if (*options == ',') 315 options++; 316 *data = (void *) options; 317 return sb_block; 318 } 319 320 enum { 321 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 322 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 323 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 324 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 325 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, 326 Opt_usrquota, Opt_grpquota 327 }; 328 329 static match_table_t tokens = { 330 {Opt_bsd_df, "bsddf"}, 331 {Opt_minix_df, "minixdf"}, 332 {Opt_grpid, "grpid"}, 333 {Opt_grpid, "bsdgroups"}, 334 {Opt_nogrpid, "nogrpid"}, 335 {Opt_nogrpid, "sysvgroups"}, 336 {Opt_resgid, "resgid=%u"}, 337 {Opt_resuid, "resuid=%u"}, 338 {Opt_sb, "sb=%u"}, 339 {Opt_err_cont, "errors=continue"}, 340 {Opt_err_panic, "errors=panic"}, 341 {Opt_err_ro, "errors=remount-ro"}, 342 {Opt_nouid32, "nouid32"}, 343 {Opt_nocheck, "check=none"}, 344 {Opt_nocheck, "nocheck"}, 345 {Opt_debug, "debug"}, 346 {Opt_oldalloc, "oldalloc"}, 347 {Opt_orlov, "orlov"}, 348 {Opt_nobh, "nobh"}, 349 {Opt_user_xattr, "user_xattr"}, 350 {Opt_nouser_xattr, "nouser_xattr"}, 351 {Opt_acl, "acl"}, 352 {Opt_noacl, "noacl"}, 353 {Opt_xip, "xip"}, 354 {Opt_grpquota, "grpquota"}, 355 {Opt_ignore, "noquota"}, 356 {Opt_quota, "quota"}, 357 {Opt_usrquota, "usrquota"}, 358 {Opt_err, NULL} 359 }; 360 361 static int parse_options (char * options, 362 struct ext2_sb_info *sbi) 363 { 364 char * p; 365 substring_t args[MAX_OPT_ARGS]; 366 int option; 367 368 if (!options) 369 return 1; 370 371 while ((p = strsep (&options, ",")) != NULL) { 372 int token; 373 if (!*p) 374 continue; 375 376 token = match_token(p, tokens, args); 377 switch (token) { 378 case Opt_bsd_df: 379 clear_opt (sbi->s_mount_opt, MINIX_DF); 380 break; 381 case Opt_minix_df: 382 set_opt (sbi->s_mount_opt, MINIX_DF); 383 break; 384 case Opt_grpid: 385 set_opt (sbi->s_mount_opt, GRPID); 386 break; 387 case Opt_nogrpid: 388 clear_opt (sbi->s_mount_opt, GRPID); 389 break; 390 case Opt_resuid: 391 if (match_int(&args[0], &option)) 392 return 0; 393 sbi->s_resuid = option; 394 break; 395 case Opt_resgid: 396 if (match_int(&args[0], &option)) 397 return 0; 398 sbi->s_resgid = option; 399 break; 400 case Opt_sb: 401 /* handled by get_sb_block() instead of here */ 402 /* *sb_block = match_int(&args[0]); */ 403 break; 404 case Opt_err_panic: 405 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 406 clear_opt (sbi->s_mount_opt, ERRORS_RO); 407 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 408 break; 409 case Opt_err_ro: 410 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 411 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 412 set_opt (sbi->s_mount_opt, ERRORS_RO); 413 break; 414 case Opt_err_cont: 415 clear_opt (sbi->s_mount_opt, ERRORS_RO); 416 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 417 set_opt (sbi->s_mount_opt, ERRORS_CONT); 418 break; 419 case Opt_nouid32: 420 set_opt (sbi->s_mount_opt, NO_UID32); 421 break; 422 case Opt_nocheck: 423 clear_opt (sbi->s_mount_opt, CHECK); 424 break; 425 case Opt_debug: 426 set_opt (sbi->s_mount_opt, DEBUG); 427 break; 428 case Opt_oldalloc: 429 set_opt (sbi->s_mount_opt, OLDALLOC); 430 break; 431 case Opt_orlov: 432 clear_opt (sbi->s_mount_opt, OLDALLOC); 433 break; 434 case Opt_nobh: 435 set_opt (sbi->s_mount_opt, NOBH); 436 break; 437 #ifdef CONFIG_EXT2_FS_XATTR 438 case Opt_user_xattr: 439 set_opt (sbi->s_mount_opt, XATTR_USER); 440 break; 441 case Opt_nouser_xattr: 442 clear_opt (sbi->s_mount_opt, XATTR_USER); 443 break; 444 #else 445 case Opt_user_xattr: 446 case Opt_nouser_xattr: 447 printk("EXT2 (no)user_xattr options not supported\n"); 448 break; 449 #endif 450 #ifdef CONFIG_EXT2_FS_POSIX_ACL 451 case Opt_acl: 452 set_opt(sbi->s_mount_opt, POSIX_ACL); 453 break; 454 case Opt_noacl: 455 clear_opt(sbi->s_mount_opt, POSIX_ACL); 456 break; 457 #else 458 case Opt_acl: 459 case Opt_noacl: 460 printk("EXT2 (no)acl options not supported\n"); 461 break; 462 #endif 463 case Opt_xip: 464 #ifdef CONFIG_EXT2_FS_XIP 465 set_opt (sbi->s_mount_opt, XIP); 466 #else 467 printk("EXT2 xip option not supported\n"); 468 #endif 469 break; 470 471 #if defined(CONFIG_QUOTA) 472 case Opt_quota: 473 case Opt_usrquota: 474 set_opt(sbi->s_mount_opt, USRQUOTA); 475 break; 476 477 case Opt_grpquota: 478 set_opt(sbi->s_mount_opt, GRPQUOTA); 479 break; 480 #else 481 case Opt_quota: 482 case Opt_usrquota: 483 case Opt_grpquota: 484 printk(KERN_ERR 485 "EXT2-fs: quota operations not supported.\n"); 486 487 break; 488 #endif 489 490 case Opt_ignore: 491 break; 492 default: 493 return 0; 494 } 495 } 496 return 1; 497 } 498 499 static int ext2_setup_super (struct super_block * sb, 500 struct ext2_super_block * es, 501 int read_only) 502 { 503 int res = 0; 504 struct ext2_sb_info *sbi = EXT2_SB(sb); 505 506 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 507 printk ("EXT2-fs warning: revision level too high, " 508 "forcing read-only mode\n"); 509 res = MS_RDONLY; 510 } 511 if (read_only) 512 return res; 513 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 514 printk ("EXT2-fs warning: mounting unchecked fs, " 515 "running e2fsck is recommended\n"); 516 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 517 printk ("EXT2-fs warning: mounting fs with errors, " 518 "running e2fsck is recommended\n"); 519 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 520 le16_to_cpu(es->s_mnt_count) >= 521 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 522 printk ("EXT2-fs warning: maximal mount count reached, " 523 "running e2fsck is recommended\n"); 524 else if (le32_to_cpu(es->s_checkinterval) && 525 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds())) 526 printk ("EXT2-fs warning: checktime reached, " 527 "running e2fsck is recommended\n"); 528 if (!le16_to_cpu(es->s_max_mnt_count)) 529 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 530 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1); 531 ext2_write_super(sb); 532 if (test_opt (sb, DEBUG)) 533 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, " 534 "bpg=%lu, ipg=%lu, mo=%04lx]\n", 535 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 536 sbi->s_frag_size, 537 sbi->s_groups_count, 538 EXT2_BLOCKS_PER_GROUP(sb), 539 EXT2_INODES_PER_GROUP(sb), 540 sbi->s_mount_opt); 541 return res; 542 } 543 544 static int ext2_check_descriptors (struct super_block * sb) 545 { 546 int i; 547 int desc_block = 0; 548 struct ext2_sb_info *sbi = EXT2_SB(sb); 549 unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block); 550 unsigned long last_block; 551 struct ext2_group_desc * gdp = NULL; 552 553 ext2_debug ("Checking group descriptors"); 554 555 for (i = 0; i < sbi->s_groups_count; i++) 556 { 557 if (i == sbi->s_groups_count - 1) 558 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 559 else 560 last_block = first_block + 561 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 562 563 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0) 564 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data; 565 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 566 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 567 { 568 ext2_error (sb, "ext2_check_descriptors", 569 "Block bitmap for group %d" 570 " not in group (block %lu)!", 571 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 572 return 0; 573 } 574 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 575 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 576 { 577 ext2_error (sb, "ext2_check_descriptors", 578 "Inode bitmap for group %d" 579 " not in group (block %lu)!", 580 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 581 return 0; 582 } 583 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 584 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group > 585 last_block) 586 { 587 ext2_error (sb, "ext2_check_descriptors", 588 "Inode table for group %d" 589 " not in group (block %lu)!", 590 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 591 return 0; 592 } 593 first_block += EXT2_BLOCKS_PER_GROUP(sb); 594 gdp++; 595 } 596 return 1; 597 } 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 #ifdef CONFIG_EXT2_FS_XATTR 711 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 712 set_opt(sbi->s_mount_opt, XATTR_USER); 713 #endif 714 #ifdef CONFIG_EXT2_FS_POSIX_ACL 715 if (def_mount_opts & EXT2_DEFM_ACL) 716 set_opt(sbi->s_mount_opt, POSIX_ACL); 717 #endif 718 719 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 720 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 721 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO) 722 set_opt(sbi->s_mount_opt, ERRORS_RO); 723 else 724 set_opt(sbi->s_mount_opt, ERRORS_CONT); 725 726 sbi->s_resuid = le16_to_cpu(es->s_def_resuid); 727 sbi->s_resgid = le16_to_cpu(es->s_def_resgid); 728 729 if (!parse_options ((char *) data, sbi)) 730 goto failed_mount; 731 732 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 733 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 734 MS_POSIXACL : 0); 735 736 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 737 EXT2_MOUNT_XIP if not */ 738 739 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 740 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 741 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 742 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 743 printk("EXT2-fs warning: feature flags set on rev 0 fs, " 744 "running e2fsck is recommended\n"); 745 /* 746 * Check feature flags regardless of the revision level, since we 747 * previously didn't change the revision level when setting the flags, 748 * so there is a chance incompat flags are set on a rev 0 filesystem. 749 */ 750 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 751 if (features) { 752 printk("EXT2-fs: %s: couldn't mount because of " 753 "unsupported optional features (%x).\n", 754 sb->s_id, le32_to_cpu(features)); 755 goto failed_mount; 756 } 757 if (!(sb->s_flags & MS_RDONLY) && 758 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 759 printk("EXT2-fs: %s: couldn't mount RDWR because of " 760 "unsupported optional features (%x).\n", 761 sb->s_id, le32_to_cpu(features)); 762 goto failed_mount; 763 } 764 765 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 766 767 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) || 768 (sb->s_blocksize != blocksize))) { 769 if (!silent) 770 printk("XIP: Unsupported blocksize\n"); 771 goto failed_mount; 772 } 773 774 /* If the blocksize doesn't match, re-read the thing.. */ 775 if (sb->s_blocksize != blocksize) { 776 brelse(bh); 777 778 if (!sb_set_blocksize(sb, blocksize)) { 779 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); 780 goto failed_sbi; 781 } 782 783 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 784 offset = (sb_block*BLOCK_SIZE) % blocksize; 785 bh = sb_bread(sb, logic_sb_block); 786 if(!bh) { 787 printk("EXT2-fs: Couldn't read superblock on " 788 "2nd try.\n"); 789 goto failed_sbi; 790 } 791 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 792 sbi->s_es = es; 793 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 794 printk ("EXT2-fs: Magic mismatch, very weird !\n"); 795 goto failed_mount; 796 } 797 } 798 799 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 800 801 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 802 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 803 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 804 } else { 805 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 806 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 807 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 808 (sbi->s_inode_size & (sbi->s_inode_size - 1)) || 809 (sbi->s_inode_size > blocksize)) { 810 printk ("EXT2-fs: unsupported inode size: %d\n", 811 sbi->s_inode_size); 812 goto failed_mount; 813 } 814 } 815 816 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 817 le32_to_cpu(es->s_log_frag_size); 818 if (sbi->s_frag_size == 0) 819 goto cantfind_ext2; 820 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 821 822 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 823 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 824 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 825 826 if (EXT2_INODE_SIZE(sb) == 0) 827 goto cantfind_ext2; 828 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 829 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 830 goto cantfind_ext2; 831 sbi->s_itb_per_group = sbi->s_inodes_per_group / 832 sbi->s_inodes_per_block; 833 sbi->s_desc_per_block = sb->s_blocksize / 834 sizeof (struct ext2_group_desc); 835 sbi->s_sbh = bh; 836 sbi->s_mount_state = le16_to_cpu(es->s_state); 837 sbi->s_addr_per_block_bits = 838 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 839 sbi->s_desc_per_block_bits = 840 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 841 842 if (sb->s_magic != EXT2_SUPER_MAGIC) 843 goto cantfind_ext2; 844 845 if (sb->s_blocksize != bh->b_size) { 846 if (!silent) 847 printk ("VFS: Unsupported blocksize on dev " 848 "%s.\n", sb->s_id); 849 goto failed_mount; 850 } 851 852 if (sb->s_blocksize != sbi->s_frag_size) { 853 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n", 854 sbi->s_frag_size, sb->s_blocksize); 855 goto failed_mount; 856 } 857 858 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 859 printk ("EXT2-fs: #blocks per group too big: %lu\n", 860 sbi->s_blocks_per_group); 861 goto failed_mount; 862 } 863 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 864 printk ("EXT2-fs: #fragments per group too big: %lu\n", 865 sbi->s_frags_per_group); 866 goto failed_mount; 867 } 868 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 869 printk ("EXT2-fs: #inodes per group too big: %lu\n", 870 sbi->s_inodes_per_group); 871 goto failed_mount; 872 } 873 874 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 875 goto cantfind_ext2; 876 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 877 le32_to_cpu(es->s_first_data_block) - 1) 878 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 879 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 880 EXT2_DESC_PER_BLOCK(sb); 881 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 882 if (sbi->s_group_desc == NULL) { 883 printk ("EXT2-fs: not enough memory\n"); 884 goto failed_mount; 885 } 886 bgl_lock_init(&sbi->s_blockgroup_lock); 887 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts), 888 GFP_KERNEL); 889 if (!sbi->s_debts) { 890 printk ("EXT2-fs: not enough memory\n"); 891 goto failed_mount_group_desc; 892 } 893 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts)); 894 for (i = 0; i < db_count; i++) { 895 block = descriptor_loc(sb, logic_sb_block, i); 896 sbi->s_group_desc[i] = sb_bread(sb, block); 897 if (!sbi->s_group_desc[i]) { 898 for (j = 0; j < i; j++) 899 brelse (sbi->s_group_desc[j]); 900 printk ("EXT2-fs: unable to read group descriptors\n"); 901 goto failed_mount_group_desc; 902 } 903 } 904 if (!ext2_check_descriptors (sb)) { 905 printk ("EXT2-fs: group descriptors corrupted!\n"); 906 goto failed_mount2; 907 } 908 sbi->s_gdb_count = db_count; 909 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 910 spin_lock_init(&sbi->s_next_gen_lock); 911 912 percpu_counter_init(&sbi->s_freeblocks_counter, 913 ext2_count_free_blocks(sb)); 914 percpu_counter_init(&sbi->s_freeinodes_counter, 915 ext2_count_free_inodes(sb)); 916 percpu_counter_init(&sbi->s_dirs_counter, 917 ext2_count_dirs(sb)); 918 /* 919 * set up enough so that it can read an inode 920 */ 921 sb->s_op = &ext2_sops; 922 sb->s_export_op = &ext2_export_ops; 923 sb->s_xattr = ext2_xattr_handlers; 924 root = iget(sb, EXT2_ROOT_INO); 925 sb->s_root = d_alloc_root(root); 926 if (!sb->s_root) { 927 iput(root); 928 printk(KERN_ERR "EXT2-fs: get root inode failed\n"); 929 goto failed_mount3; 930 } 931 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 932 dput(sb->s_root); 933 sb->s_root = NULL; 934 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n"); 935 goto failed_mount3; 936 } 937 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 938 ext2_warning(sb, __FUNCTION__, 939 "mounting ext3 filesystem as ext2"); 940 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); 941 return 0; 942 943 cantfind_ext2: 944 if (!silent) 945 printk("VFS: Can't find an ext2 filesystem on dev %s.\n", 946 sb->s_id); 947 goto failed_mount; 948 failed_mount3: 949 percpu_counter_destroy(&sbi->s_freeblocks_counter); 950 percpu_counter_destroy(&sbi->s_freeinodes_counter); 951 percpu_counter_destroy(&sbi->s_dirs_counter); 952 failed_mount2: 953 for (i = 0; i < db_count; i++) 954 brelse(sbi->s_group_desc[i]); 955 failed_mount_group_desc: 956 kfree(sbi->s_group_desc); 957 kfree(sbi->s_debts); 958 failed_mount: 959 brelse(bh); 960 failed_sbi: 961 sb->s_fs_info = NULL; 962 kfree(sbi); 963 return -EINVAL; 964 } 965 966 static void ext2_commit_super (struct super_block * sb, 967 struct ext2_super_block * es) 968 { 969 es->s_wtime = cpu_to_le32(get_seconds()); 970 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 971 sb->s_dirt = 0; 972 } 973 974 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) 975 { 976 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 977 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 978 es->s_wtime = cpu_to_le32(get_seconds()); 979 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 980 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 981 sb->s_dirt = 0; 982 } 983 984 /* 985 * In the second extended file system, it is not necessary to 986 * write the super block since we use a mapping of the 987 * disk super block in a buffer. 988 * 989 * However, this function is still used to set the fs valid 990 * flags to 0. We need to set this flag to 0 since the fs 991 * may have been checked while mounted and e2fsck may have 992 * set s_state to EXT2_VALID_FS after some corrections. 993 */ 994 995 void ext2_write_super (struct super_block * sb) 996 { 997 struct ext2_super_block * es; 998 lock_kernel(); 999 if (!(sb->s_flags & MS_RDONLY)) { 1000 es = EXT2_SB(sb)->s_es; 1001 1002 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) { 1003 ext2_debug ("setting valid to 0\n"); 1004 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & 1005 ~EXT2_VALID_FS); 1006 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1007 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1008 es->s_mtime = cpu_to_le32(get_seconds()); 1009 ext2_sync_super(sb, es); 1010 } else 1011 ext2_commit_super (sb, es); 1012 } 1013 sb->s_dirt = 0; 1014 unlock_kernel(); 1015 } 1016 1017 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1018 { 1019 struct ext2_sb_info * sbi = EXT2_SB(sb); 1020 struct ext2_super_block * es; 1021 unsigned long old_mount_opt = sbi->s_mount_opt; 1022 struct ext2_mount_options old_opts; 1023 unsigned long old_sb_flags; 1024 int err; 1025 1026 /* Store the old options */ 1027 old_sb_flags = sb->s_flags; 1028 old_opts.s_mount_opt = sbi->s_mount_opt; 1029 old_opts.s_resuid = sbi->s_resuid; 1030 old_opts.s_resgid = sbi->s_resgid; 1031 1032 /* 1033 * Allow the "check" option to be passed as a remount option. 1034 */ 1035 if (!parse_options (data, sbi)) { 1036 err = -EINVAL; 1037 goto restore_opts; 1038 } 1039 1040 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1041 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1042 1043 es = sbi->s_es; 1044 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) != 1045 (old_mount_opt & EXT2_MOUNT_XIP)) && 1046 invalidate_inodes(sb)) 1047 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\ 1048 "xip remain in cache (no functional problem)"); 1049 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 1050 return 0; 1051 if (*flags & MS_RDONLY) { 1052 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1053 !(sbi->s_mount_state & EXT2_VALID_FS)) 1054 return 0; 1055 /* 1056 * OK, we are remounting a valid rw partition rdonly, so set 1057 * the rdonly flag and then mark the partition as valid again. 1058 */ 1059 es->s_state = cpu_to_le16(sbi->s_mount_state); 1060 es->s_mtime = cpu_to_le32(get_seconds()); 1061 } else { 1062 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1063 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1064 if (ret) { 1065 printk("EXT2-fs: %s: couldn't remount RDWR because of " 1066 "unsupported optional features (%x).\n", 1067 sb->s_id, le32_to_cpu(ret)); 1068 err = -EROFS; 1069 goto restore_opts; 1070 } 1071 /* 1072 * Mounting a RDONLY partition read-write, so reread and 1073 * store the current valid flag. (It may have been changed 1074 * by e2fsck since we originally mounted the partition.) 1075 */ 1076 sbi->s_mount_state = le16_to_cpu(es->s_state); 1077 if (!ext2_setup_super (sb, es, 0)) 1078 sb->s_flags &= ~MS_RDONLY; 1079 } 1080 ext2_sync_super(sb, es); 1081 return 0; 1082 restore_opts: 1083 sbi->s_mount_opt = old_opts.s_mount_opt; 1084 sbi->s_resuid = old_opts.s_resuid; 1085 sbi->s_resgid = old_opts.s_resgid; 1086 sb->s_flags = old_sb_flags; 1087 return err; 1088 } 1089 1090 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1091 { 1092 struct super_block *sb = dentry->d_sb; 1093 struct ext2_sb_info *sbi = EXT2_SB(sb); 1094 struct ext2_super_block *es = sbi->s_es; 1095 unsigned long overhead; 1096 int i; 1097 u64 fsid; 1098 1099 if (test_opt (sb, MINIX_DF)) 1100 overhead = 0; 1101 else { 1102 /* 1103 * Compute the overhead (FS structures) 1104 */ 1105 1106 /* 1107 * All of the blocks before first_data_block are 1108 * overhead 1109 */ 1110 overhead = le32_to_cpu(es->s_first_data_block); 1111 1112 /* 1113 * Add the overhead attributed to the superblock and 1114 * block group descriptors. If the sparse superblocks 1115 * feature is turned on, then not all groups have this. 1116 */ 1117 for (i = 0; i < sbi->s_groups_count; i++) 1118 overhead += ext2_bg_has_super(sb, i) + 1119 ext2_bg_num_gdb(sb, i); 1120 1121 /* 1122 * Every block group has an inode bitmap, a block 1123 * bitmap, and an inode table. 1124 */ 1125 overhead += (sbi->s_groups_count * 1126 (2 + sbi->s_itb_per_group)); 1127 } 1128 1129 buf->f_type = EXT2_SUPER_MAGIC; 1130 buf->f_bsize = sb->s_blocksize; 1131 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - overhead; 1132 buf->f_bfree = ext2_count_free_blocks(sb); 1133 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1134 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1135 buf->f_bavail = 0; 1136 buf->f_files = le32_to_cpu(es->s_inodes_count); 1137 buf->f_ffree = ext2_count_free_inodes(sb); 1138 buf->f_namelen = EXT2_NAME_LEN; 1139 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1140 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1141 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1142 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1143 return 0; 1144 } 1145 1146 static int ext2_get_sb(struct file_system_type *fs_type, 1147 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 1148 { 1149 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt); 1150 } 1151 1152 #ifdef CONFIG_QUOTA 1153 1154 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1155 * acquiring the locks... As quota files are never truncated and quota code 1156 * itself serializes the operations (and noone else should touch the files) 1157 * we don't have to be afraid of races */ 1158 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1159 size_t len, loff_t off) 1160 { 1161 struct inode *inode = sb_dqopt(sb)->files[type]; 1162 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1163 int err = 0; 1164 int offset = off & (sb->s_blocksize - 1); 1165 int tocopy; 1166 size_t toread; 1167 struct buffer_head tmp_bh; 1168 struct buffer_head *bh; 1169 loff_t i_size = i_size_read(inode); 1170 1171 if (off > i_size) 1172 return 0; 1173 if (off+len > i_size) 1174 len = i_size-off; 1175 toread = len; 1176 while (toread > 0) { 1177 tocopy = sb->s_blocksize - offset < toread ? 1178 sb->s_blocksize - offset : toread; 1179 1180 tmp_bh.b_state = 0; 1181 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1182 if (err) 1183 return err; 1184 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1185 memset(data, 0, tocopy); 1186 else { 1187 bh = sb_bread(sb, tmp_bh.b_blocknr); 1188 if (!bh) 1189 return -EIO; 1190 memcpy(data, bh->b_data+offset, tocopy); 1191 brelse(bh); 1192 } 1193 offset = 0; 1194 toread -= tocopy; 1195 data += tocopy; 1196 blk++; 1197 } 1198 return len; 1199 } 1200 1201 /* Write to quotafile */ 1202 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1203 const char *data, size_t len, loff_t off) 1204 { 1205 struct inode *inode = sb_dqopt(sb)->files[type]; 1206 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1207 int err = 0; 1208 int offset = off & (sb->s_blocksize - 1); 1209 int tocopy; 1210 size_t towrite = len; 1211 struct buffer_head tmp_bh; 1212 struct buffer_head *bh; 1213 1214 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 1215 while (towrite > 0) { 1216 tocopy = sb->s_blocksize - offset < towrite ? 1217 sb->s_blocksize - offset : towrite; 1218 1219 tmp_bh.b_state = 0; 1220 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1221 if (err) 1222 goto out; 1223 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1224 bh = sb_bread(sb, tmp_bh.b_blocknr); 1225 else 1226 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1227 if (!bh) { 1228 err = -EIO; 1229 goto out; 1230 } 1231 lock_buffer(bh); 1232 memcpy(bh->b_data+offset, data, tocopy); 1233 flush_dcache_page(bh->b_page); 1234 set_buffer_uptodate(bh); 1235 mark_buffer_dirty(bh); 1236 unlock_buffer(bh); 1237 brelse(bh); 1238 offset = 0; 1239 towrite -= tocopy; 1240 data += tocopy; 1241 blk++; 1242 } 1243 out: 1244 if (len == towrite) 1245 return err; 1246 if (inode->i_size < off+len-towrite) 1247 i_size_write(inode, off+len-towrite); 1248 inode->i_version++; 1249 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1250 mark_inode_dirty(inode); 1251 mutex_unlock(&inode->i_mutex); 1252 return len - towrite; 1253 } 1254 1255 #endif 1256 1257 static struct file_system_type ext2_fs_type = { 1258 .owner = THIS_MODULE, 1259 .name = "ext2", 1260 .get_sb = ext2_get_sb, 1261 .kill_sb = kill_block_super, 1262 .fs_flags = FS_REQUIRES_DEV, 1263 }; 1264 1265 static int __init init_ext2_fs(void) 1266 { 1267 int err = init_ext2_xattr(); 1268 if (err) 1269 return err; 1270 err = init_inodecache(); 1271 if (err) 1272 goto out1; 1273 err = register_filesystem(&ext2_fs_type); 1274 if (err) 1275 goto out; 1276 return 0; 1277 out: 1278 destroy_inodecache(); 1279 out1: 1280 exit_ext2_xattr(); 1281 return err; 1282 } 1283 1284 static void __exit exit_ext2_fs(void) 1285 { 1286 unregister_filesystem(&ext2_fs_type); 1287 destroy_inodecache(); 1288 exit_ext2_xattr(); 1289 } 1290 1291 module_init(init_ext2_fs) 1292 module_exit(exit_ext2_fs) 1293