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 rwlock_init(&ei->i_meta_lock); 164 #ifdef CONFIG_EXT2_FS_XATTR 165 init_rwsem(&ei->xattr_sem); 166 #endif 167 inode_init_once(&ei->vfs_inode); 168 } 169 170 static int init_inodecache(void) 171 { 172 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 173 sizeof(struct ext2_inode_info), 174 0, (SLAB_RECLAIM_ACCOUNT| 175 SLAB_MEM_SPREAD), 176 init_once, NULL); 177 if (ext2_inode_cachep == NULL) 178 return -ENOMEM; 179 return 0; 180 } 181 182 static void destroy_inodecache(void) 183 { 184 kmem_cache_destroy(ext2_inode_cachep); 185 } 186 187 static void ext2_clear_inode(struct inode *inode) 188 { 189 #ifdef CONFIG_EXT2_FS_POSIX_ACL 190 struct ext2_inode_info *ei = EXT2_I(inode); 191 192 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) { 193 posix_acl_release(ei->i_acl); 194 ei->i_acl = EXT2_ACL_NOT_CACHED; 195 } 196 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) { 197 posix_acl_release(ei->i_default_acl); 198 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 199 } 200 #endif 201 } 202 203 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs) 204 { 205 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb); 206 207 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID) 208 seq_puts(seq, ",grpid"); 209 210 #if defined(CONFIG_QUOTA) 211 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 212 seq_puts(seq, ",usrquota"); 213 214 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 215 seq_puts(seq, ",grpquota"); 216 #endif 217 218 #if defined(CONFIG_EXT2_FS_XIP) 219 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 220 seq_puts(seq, ",xip"); 221 #endif 222 223 return 0; 224 } 225 226 #ifdef CONFIG_QUOTA 227 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 228 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 229 #endif 230 231 static const struct super_operations ext2_sops = { 232 .alloc_inode = ext2_alloc_inode, 233 .destroy_inode = ext2_destroy_inode, 234 .read_inode = ext2_read_inode, 235 .write_inode = ext2_write_inode, 236 .put_inode = ext2_put_inode, 237 .delete_inode = ext2_delete_inode, 238 .put_super = ext2_put_super, 239 .write_super = ext2_write_super, 240 .statfs = ext2_statfs, 241 .remount_fs = ext2_remount, 242 .clear_inode = ext2_clear_inode, 243 .show_options = ext2_show_options, 244 #ifdef CONFIG_QUOTA 245 .quota_read = ext2_quota_read, 246 .quota_write = ext2_quota_write, 247 #endif 248 }; 249 250 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp) 251 { 252 __u32 *objp = vobjp; 253 unsigned long ino = objp[0]; 254 __u32 generation = objp[1]; 255 struct inode *inode; 256 struct dentry *result; 257 258 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 259 return ERR_PTR(-ESTALE); 260 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 261 return ERR_PTR(-ESTALE); 262 263 /* iget isn't really right if the inode is currently unallocated!! 264 * ext2_read_inode currently does appropriate checks, but 265 * it might be "neater" to call ext2_get_inode first and check 266 * if the inode is valid..... 267 */ 268 inode = iget(sb, ino); 269 if (inode == NULL) 270 return ERR_PTR(-ENOMEM); 271 if (is_bad_inode(inode) || 272 (generation && inode->i_generation != generation)) { 273 /* we didn't find the right inode.. */ 274 iput(inode); 275 return ERR_PTR(-ESTALE); 276 } 277 /* now to find a dentry. 278 * If possible, get a well-connected one 279 */ 280 result = d_alloc_anon(inode); 281 if (!result) { 282 iput(inode); 283 return ERR_PTR(-ENOMEM); 284 } 285 return result; 286 } 287 288 /* Yes, most of these are left as NULL!! 289 * A NULL value implies the default, which works with ext2-like file 290 * systems, but can be improved upon. 291 * Currently only get_parent is required. 292 */ 293 static struct export_operations ext2_export_ops = { 294 .get_parent = ext2_get_parent, 295 .get_dentry = ext2_get_dentry, 296 }; 297 298 static unsigned long get_sb_block(void **data) 299 { 300 unsigned long sb_block; 301 char *options = (char *) *data; 302 303 if (!options || strncmp(options, "sb=", 3) != 0) 304 return 1; /* Default location */ 305 options += 3; 306 sb_block = simple_strtoul(options, &options, 0); 307 if (*options && *options != ',') { 308 printk("EXT2-fs: Invalid sb specification: %s\n", 309 (char *) *data); 310 return 1; 311 } 312 if (*options == ',') 313 options++; 314 *data = (void *) options; 315 return sb_block; 316 } 317 318 enum { 319 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 320 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 321 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 322 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 323 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, 324 Opt_usrquota, Opt_grpquota 325 }; 326 327 static match_table_t tokens = { 328 {Opt_bsd_df, "bsddf"}, 329 {Opt_minix_df, "minixdf"}, 330 {Opt_grpid, "grpid"}, 331 {Opt_grpid, "bsdgroups"}, 332 {Opt_nogrpid, "nogrpid"}, 333 {Opt_nogrpid, "sysvgroups"}, 334 {Opt_resgid, "resgid=%u"}, 335 {Opt_resuid, "resuid=%u"}, 336 {Opt_sb, "sb=%u"}, 337 {Opt_err_cont, "errors=continue"}, 338 {Opt_err_panic, "errors=panic"}, 339 {Opt_err_ro, "errors=remount-ro"}, 340 {Opt_nouid32, "nouid32"}, 341 {Opt_nocheck, "check=none"}, 342 {Opt_nocheck, "nocheck"}, 343 {Opt_debug, "debug"}, 344 {Opt_oldalloc, "oldalloc"}, 345 {Opt_orlov, "orlov"}, 346 {Opt_nobh, "nobh"}, 347 {Opt_user_xattr, "user_xattr"}, 348 {Opt_nouser_xattr, "nouser_xattr"}, 349 {Opt_acl, "acl"}, 350 {Opt_noacl, "noacl"}, 351 {Opt_xip, "xip"}, 352 {Opt_grpquota, "grpquota"}, 353 {Opt_ignore, "noquota"}, 354 {Opt_quota, "quota"}, 355 {Opt_usrquota, "usrquota"}, 356 {Opt_err, NULL} 357 }; 358 359 static int parse_options (char * options, 360 struct ext2_sb_info *sbi) 361 { 362 char * p; 363 substring_t args[MAX_OPT_ARGS]; 364 int option; 365 366 if (!options) 367 return 1; 368 369 while ((p = strsep (&options, ",")) != NULL) { 370 int token; 371 if (!*p) 372 continue; 373 374 token = match_token(p, tokens, args); 375 switch (token) { 376 case Opt_bsd_df: 377 clear_opt (sbi->s_mount_opt, MINIX_DF); 378 break; 379 case Opt_minix_df: 380 set_opt (sbi->s_mount_opt, MINIX_DF); 381 break; 382 case Opt_grpid: 383 set_opt (sbi->s_mount_opt, GRPID); 384 break; 385 case Opt_nogrpid: 386 clear_opt (sbi->s_mount_opt, GRPID); 387 break; 388 case Opt_resuid: 389 if (match_int(&args[0], &option)) 390 return 0; 391 sbi->s_resuid = option; 392 break; 393 case Opt_resgid: 394 if (match_int(&args[0], &option)) 395 return 0; 396 sbi->s_resgid = option; 397 break; 398 case Opt_sb: 399 /* handled by get_sb_block() instead of here */ 400 /* *sb_block = match_int(&args[0]); */ 401 break; 402 case Opt_err_panic: 403 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 404 clear_opt (sbi->s_mount_opt, ERRORS_RO); 405 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 406 break; 407 case Opt_err_ro: 408 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 409 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 410 set_opt (sbi->s_mount_opt, ERRORS_RO); 411 break; 412 case Opt_err_cont: 413 clear_opt (sbi->s_mount_opt, ERRORS_RO); 414 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 415 set_opt (sbi->s_mount_opt, ERRORS_CONT); 416 break; 417 case Opt_nouid32: 418 set_opt (sbi->s_mount_opt, NO_UID32); 419 break; 420 case Opt_nocheck: 421 clear_opt (sbi->s_mount_opt, CHECK); 422 break; 423 case Opt_debug: 424 set_opt (sbi->s_mount_opt, DEBUG); 425 break; 426 case Opt_oldalloc: 427 set_opt (sbi->s_mount_opt, OLDALLOC); 428 break; 429 case Opt_orlov: 430 clear_opt (sbi->s_mount_opt, OLDALLOC); 431 break; 432 case Opt_nobh: 433 set_opt (sbi->s_mount_opt, NOBH); 434 break; 435 #ifdef CONFIG_EXT2_FS_XATTR 436 case Opt_user_xattr: 437 set_opt (sbi->s_mount_opt, XATTR_USER); 438 break; 439 case Opt_nouser_xattr: 440 clear_opt (sbi->s_mount_opt, XATTR_USER); 441 break; 442 #else 443 case Opt_user_xattr: 444 case Opt_nouser_xattr: 445 printk("EXT2 (no)user_xattr options not supported\n"); 446 break; 447 #endif 448 #ifdef CONFIG_EXT2_FS_POSIX_ACL 449 case Opt_acl: 450 set_opt(sbi->s_mount_opt, POSIX_ACL); 451 break; 452 case Opt_noacl: 453 clear_opt(sbi->s_mount_opt, POSIX_ACL); 454 break; 455 #else 456 case Opt_acl: 457 case Opt_noacl: 458 printk("EXT2 (no)acl options not supported\n"); 459 break; 460 #endif 461 case Opt_xip: 462 #ifdef CONFIG_EXT2_FS_XIP 463 set_opt (sbi->s_mount_opt, XIP); 464 #else 465 printk("EXT2 xip option not supported\n"); 466 #endif 467 break; 468 469 #if defined(CONFIG_QUOTA) 470 case Opt_quota: 471 case Opt_usrquota: 472 set_opt(sbi->s_mount_opt, USRQUOTA); 473 break; 474 475 case Opt_grpquota: 476 set_opt(sbi->s_mount_opt, GRPQUOTA); 477 break; 478 #else 479 case Opt_quota: 480 case Opt_usrquota: 481 case Opt_grpquota: 482 printk(KERN_ERR 483 "EXT2-fs: quota operations not supported.\n"); 484 485 break; 486 #endif 487 488 case Opt_ignore: 489 break; 490 default: 491 return 0; 492 } 493 } 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 /* 598 * Maximal file size. There is a direct, and {,double-,triple-}indirect 599 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 600 * We need to be 1 filesystem block less than the 2^32 sector limit. 601 */ 602 static loff_t ext2_max_size(int bits) 603 { 604 loff_t res = EXT2_NDIR_BLOCKS; 605 /* This constant is calculated to be the largest file size for a 606 * dense, 4k-blocksize file such that the total number of 607 * sectors in the file, including data and all indirect blocks, 608 * does not exceed 2^32. */ 609 const loff_t upper_limit = 0x1ff7fffd000LL; 610 611 res += 1LL << (bits-2); 612 res += 1LL << (2*(bits-2)); 613 res += 1LL << (3*(bits-2)); 614 res <<= bits; 615 if (res > upper_limit) 616 res = upper_limit; 617 return res; 618 } 619 620 static unsigned long descriptor_loc(struct super_block *sb, 621 unsigned long logic_sb_block, 622 int nr) 623 { 624 struct ext2_sb_info *sbi = EXT2_SB(sb); 625 unsigned long bg, first_data_block, first_meta_bg; 626 int has_super = 0; 627 628 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block); 629 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 630 631 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 632 nr < first_meta_bg) 633 return (logic_sb_block + nr + 1); 634 bg = sbi->s_desc_per_block * nr; 635 if (ext2_bg_has_super(sb, bg)) 636 has_super = 1; 637 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group)); 638 } 639 640 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 641 { 642 struct buffer_head * bh; 643 struct ext2_sb_info * sbi; 644 struct ext2_super_block * es; 645 struct inode *root; 646 unsigned long block; 647 unsigned long sb_block = get_sb_block(&data); 648 unsigned long logic_sb_block; 649 unsigned long offset = 0; 650 unsigned long def_mount_opts; 651 int blocksize = BLOCK_SIZE; 652 int db_count; 653 int i, j; 654 __le32 features; 655 656 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 657 if (!sbi) 658 return -ENOMEM; 659 sb->s_fs_info = sbi; 660 661 /* 662 * See what the current blocksize for the device is, and 663 * use that as the blocksize. Otherwise (or if the blocksize 664 * is smaller than the default) use the default. 665 * This is important for devices that have a hardware 666 * sectorsize that is larger than the default. 667 */ 668 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 669 if (!blocksize) { 670 printk ("EXT2-fs: unable to set blocksize\n"); 671 goto failed_sbi; 672 } 673 674 /* 675 * If the superblock doesn't start on a hardware sector boundary, 676 * calculate the offset. 677 */ 678 if (blocksize != BLOCK_SIZE) { 679 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 680 offset = (sb_block*BLOCK_SIZE) % blocksize; 681 } else { 682 logic_sb_block = sb_block; 683 } 684 685 if (!(bh = sb_bread(sb, logic_sb_block))) { 686 printk ("EXT2-fs: unable to read superblock\n"); 687 goto failed_sbi; 688 } 689 /* 690 * Note: s_es must be initialized as soon as possible because 691 * some ext2 macro-instructions depend on its value 692 */ 693 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 694 sbi->s_es = es; 695 sb->s_magic = le16_to_cpu(es->s_magic); 696 697 if (sb->s_magic != EXT2_SUPER_MAGIC) 698 goto cantfind_ext2; 699 700 /* Set defaults before we parse the mount options */ 701 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 702 if (def_mount_opts & EXT2_DEFM_DEBUG) 703 set_opt(sbi->s_mount_opt, DEBUG); 704 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 705 set_opt(sbi->s_mount_opt, GRPID); 706 if (def_mount_opts & EXT2_DEFM_UID16) 707 set_opt(sbi->s_mount_opt, NO_UID32); 708 #ifdef CONFIG_EXT2_FS_XATTR 709 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 710 set_opt(sbi->s_mount_opt, XATTR_USER); 711 #endif 712 #ifdef CONFIG_EXT2_FS_POSIX_ACL 713 if (def_mount_opts & EXT2_DEFM_ACL) 714 set_opt(sbi->s_mount_opt, POSIX_ACL); 715 #endif 716 717 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 718 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 719 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO) 720 set_opt(sbi->s_mount_opt, ERRORS_RO); 721 else 722 set_opt(sbi->s_mount_opt, ERRORS_CONT); 723 724 sbi->s_resuid = le16_to_cpu(es->s_def_resuid); 725 sbi->s_resgid = le16_to_cpu(es->s_def_resgid); 726 727 if (!parse_options ((char *) data, sbi)) 728 goto failed_mount; 729 730 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 731 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 732 MS_POSIXACL : 0); 733 734 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 735 EXT2_MOUNT_XIP if not */ 736 737 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 738 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 739 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 740 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 741 printk("EXT2-fs warning: feature flags set on rev 0 fs, " 742 "running e2fsck is recommended\n"); 743 /* 744 * Check feature flags regardless of the revision level, since we 745 * previously didn't change the revision level when setting the flags, 746 * so there is a chance incompat flags are set on a rev 0 filesystem. 747 */ 748 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 749 if (features) { 750 printk("EXT2-fs: %s: couldn't mount because of " 751 "unsupported optional features (%x).\n", 752 sb->s_id, le32_to_cpu(features)); 753 goto failed_mount; 754 } 755 if (!(sb->s_flags & MS_RDONLY) && 756 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 757 printk("EXT2-fs: %s: couldn't mount RDWR because of " 758 "unsupported optional features (%x).\n", 759 sb->s_id, le32_to_cpu(features)); 760 goto failed_mount; 761 } 762 763 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 764 765 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) || 766 (sb->s_blocksize != blocksize))) { 767 if (!silent) 768 printk("XIP: Unsupported blocksize\n"); 769 goto failed_mount; 770 } 771 772 /* If the blocksize doesn't match, re-read the thing.. */ 773 if (sb->s_blocksize != blocksize) { 774 brelse(bh); 775 776 if (!sb_set_blocksize(sb, blocksize)) { 777 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); 778 goto failed_sbi; 779 } 780 781 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 782 offset = (sb_block*BLOCK_SIZE) % blocksize; 783 bh = sb_bread(sb, logic_sb_block); 784 if(!bh) { 785 printk("EXT2-fs: Couldn't read superblock on " 786 "2nd try.\n"); 787 goto failed_sbi; 788 } 789 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 790 sbi->s_es = es; 791 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 792 printk ("EXT2-fs: Magic mismatch, very weird !\n"); 793 goto failed_mount; 794 } 795 } 796 797 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 798 799 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 800 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 801 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 802 } else { 803 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 804 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 805 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 806 (sbi->s_inode_size & (sbi->s_inode_size - 1)) || 807 (sbi->s_inode_size > blocksize)) { 808 printk ("EXT2-fs: unsupported inode size: %d\n", 809 sbi->s_inode_size); 810 goto failed_mount; 811 } 812 } 813 814 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 815 le32_to_cpu(es->s_log_frag_size); 816 if (sbi->s_frag_size == 0) 817 goto cantfind_ext2; 818 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 819 820 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 821 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 822 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 823 824 if (EXT2_INODE_SIZE(sb) == 0) 825 goto cantfind_ext2; 826 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 827 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 828 goto cantfind_ext2; 829 sbi->s_itb_per_group = sbi->s_inodes_per_group / 830 sbi->s_inodes_per_block; 831 sbi->s_desc_per_block = sb->s_blocksize / 832 sizeof (struct ext2_group_desc); 833 sbi->s_sbh = bh; 834 sbi->s_mount_state = le16_to_cpu(es->s_state); 835 sbi->s_addr_per_block_bits = 836 ilog2 (EXT2_ADDR_PER_BLOCK(sb)); 837 sbi->s_desc_per_block_bits = 838 ilog2 (EXT2_DESC_PER_BLOCK(sb)); 839 840 if (sb->s_magic != EXT2_SUPER_MAGIC) 841 goto cantfind_ext2; 842 843 if (sb->s_blocksize != bh->b_size) { 844 if (!silent) 845 printk ("VFS: Unsupported blocksize on dev " 846 "%s.\n", sb->s_id); 847 goto failed_mount; 848 } 849 850 if (sb->s_blocksize != sbi->s_frag_size) { 851 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n", 852 sbi->s_frag_size, sb->s_blocksize); 853 goto failed_mount; 854 } 855 856 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 857 printk ("EXT2-fs: #blocks per group too big: %lu\n", 858 sbi->s_blocks_per_group); 859 goto failed_mount; 860 } 861 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 862 printk ("EXT2-fs: #fragments per group too big: %lu\n", 863 sbi->s_frags_per_group); 864 goto failed_mount; 865 } 866 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 867 printk ("EXT2-fs: #inodes per group too big: %lu\n", 868 sbi->s_inodes_per_group); 869 goto failed_mount; 870 } 871 872 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 873 goto cantfind_ext2; 874 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 875 le32_to_cpu(es->s_first_data_block) - 1) 876 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 877 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 878 EXT2_DESC_PER_BLOCK(sb); 879 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 880 if (sbi->s_group_desc == NULL) { 881 printk ("EXT2-fs: not enough memory\n"); 882 goto failed_mount; 883 } 884 bgl_lock_init(&sbi->s_blockgroup_lock); 885 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts), 886 GFP_KERNEL); 887 if (!sbi->s_debts) { 888 printk ("EXT2-fs: not enough memory\n"); 889 goto failed_mount_group_desc; 890 } 891 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts)); 892 for (i = 0; i < db_count; i++) { 893 block = descriptor_loc(sb, logic_sb_block, i); 894 sbi->s_group_desc[i] = sb_bread(sb, block); 895 if (!sbi->s_group_desc[i]) { 896 for (j = 0; j < i; j++) 897 brelse (sbi->s_group_desc[j]); 898 printk ("EXT2-fs: unable to read group descriptors\n"); 899 goto failed_mount_group_desc; 900 } 901 } 902 if (!ext2_check_descriptors (sb)) { 903 printk ("EXT2-fs: group descriptors corrupted!\n"); 904 goto failed_mount2; 905 } 906 sbi->s_gdb_count = db_count; 907 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 908 spin_lock_init(&sbi->s_next_gen_lock); 909 910 percpu_counter_init(&sbi->s_freeblocks_counter, 911 ext2_count_free_blocks(sb)); 912 percpu_counter_init(&sbi->s_freeinodes_counter, 913 ext2_count_free_inodes(sb)); 914 percpu_counter_init(&sbi->s_dirs_counter, 915 ext2_count_dirs(sb)); 916 /* 917 * set up enough so that it can read an inode 918 */ 919 sb->s_op = &ext2_sops; 920 sb->s_export_op = &ext2_export_ops; 921 sb->s_xattr = ext2_xattr_handlers; 922 root = iget(sb, EXT2_ROOT_INO); 923 sb->s_root = d_alloc_root(root); 924 if (!sb->s_root) { 925 iput(root); 926 printk(KERN_ERR "EXT2-fs: get root inode failed\n"); 927 goto failed_mount3; 928 } 929 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 930 dput(sb->s_root); 931 sb->s_root = NULL; 932 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n"); 933 goto failed_mount3; 934 } 935 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 936 ext2_warning(sb, __FUNCTION__, 937 "mounting ext3 filesystem as ext2"); 938 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); 939 return 0; 940 941 cantfind_ext2: 942 if (!silent) 943 printk("VFS: Can't find an ext2 filesystem on dev %s.\n", 944 sb->s_id); 945 goto failed_mount; 946 failed_mount3: 947 percpu_counter_destroy(&sbi->s_freeblocks_counter); 948 percpu_counter_destroy(&sbi->s_freeinodes_counter); 949 percpu_counter_destroy(&sbi->s_dirs_counter); 950 failed_mount2: 951 for (i = 0; i < db_count; i++) 952 brelse(sbi->s_group_desc[i]); 953 failed_mount_group_desc: 954 kfree(sbi->s_group_desc); 955 kfree(sbi->s_debts); 956 failed_mount: 957 brelse(bh); 958 failed_sbi: 959 sb->s_fs_info = NULL; 960 kfree(sbi); 961 return -EINVAL; 962 } 963 964 static void ext2_commit_super (struct super_block * sb, 965 struct ext2_super_block * es) 966 { 967 es->s_wtime = cpu_to_le32(get_seconds()); 968 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 969 sb->s_dirt = 0; 970 } 971 972 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) 973 { 974 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 975 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 976 es->s_wtime = cpu_to_le32(get_seconds()); 977 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 978 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 979 sb->s_dirt = 0; 980 } 981 982 /* 983 * In the second extended file system, it is not necessary to 984 * write the super block since we use a mapping of the 985 * disk super block in a buffer. 986 * 987 * However, this function is still used to set the fs valid 988 * flags to 0. We need to set this flag to 0 since the fs 989 * may have been checked while mounted and e2fsck may have 990 * set s_state to EXT2_VALID_FS after some corrections. 991 */ 992 993 void ext2_write_super (struct super_block * sb) 994 { 995 struct ext2_super_block * es; 996 lock_kernel(); 997 if (!(sb->s_flags & MS_RDONLY)) { 998 es = EXT2_SB(sb)->s_es; 999 1000 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) { 1001 ext2_debug ("setting valid to 0\n"); 1002 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & 1003 ~EXT2_VALID_FS); 1004 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1005 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1006 es->s_mtime = cpu_to_le32(get_seconds()); 1007 ext2_sync_super(sb, es); 1008 } else 1009 ext2_commit_super (sb, es); 1010 } 1011 sb->s_dirt = 0; 1012 unlock_kernel(); 1013 } 1014 1015 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1016 { 1017 struct ext2_sb_info * sbi = EXT2_SB(sb); 1018 struct ext2_super_block * es; 1019 unsigned long old_mount_opt = sbi->s_mount_opt; 1020 struct ext2_mount_options old_opts; 1021 unsigned long old_sb_flags; 1022 int err; 1023 1024 /* Store the old options */ 1025 old_sb_flags = sb->s_flags; 1026 old_opts.s_mount_opt = sbi->s_mount_opt; 1027 old_opts.s_resuid = sbi->s_resuid; 1028 old_opts.s_resgid = sbi->s_resgid; 1029 1030 /* 1031 * Allow the "check" option to be passed as a remount option. 1032 */ 1033 if (!parse_options (data, sbi)) { 1034 err = -EINVAL; 1035 goto restore_opts; 1036 } 1037 1038 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1039 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1040 1041 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 1042 EXT2_MOUNT_XIP if not */ 1043 1044 if ((ext2_use_xip(sb)) && (sb->s_blocksize != PAGE_SIZE)) { 1045 printk("XIP: Unsupported blocksize\n"); 1046 err = -EINVAL; 1047 goto restore_opts; 1048 } 1049 1050 es = sbi->s_es; 1051 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) != 1052 (old_mount_opt & EXT2_MOUNT_XIP)) && 1053 invalidate_inodes(sb)) 1054 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\ 1055 "xip remain in cache (no functional problem)"); 1056 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 1057 return 0; 1058 if (*flags & MS_RDONLY) { 1059 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1060 !(sbi->s_mount_state & EXT2_VALID_FS)) 1061 return 0; 1062 /* 1063 * OK, we are remounting a valid rw partition rdonly, so set 1064 * the rdonly flag and then mark the partition as valid again. 1065 */ 1066 es->s_state = cpu_to_le16(sbi->s_mount_state); 1067 es->s_mtime = cpu_to_le32(get_seconds()); 1068 } else { 1069 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1070 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1071 if (ret) { 1072 printk("EXT2-fs: %s: couldn't remount RDWR because of " 1073 "unsupported optional features (%x).\n", 1074 sb->s_id, le32_to_cpu(ret)); 1075 err = -EROFS; 1076 goto restore_opts; 1077 } 1078 /* 1079 * Mounting a RDONLY partition read-write, so reread and 1080 * store the current valid flag. (It may have been changed 1081 * by e2fsck since we originally mounted the partition.) 1082 */ 1083 sbi->s_mount_state = le16_to_cpu(es->s_state); 1084 if (!ext2_setup_super (sb, es, 0)) 1085 sb->s_flags &= ~MS_RDONLY; 1086 } 1087 ext2_sync_super(sb, es); 1088 return 0; 1089 restore_opts: 1090 sbi->s_mount_opt = old_opts.s_mount_opt; 1091 sbi->s_resuid = old_opts.s_resuid; 1092 sbi->s_resgid = old_opts.s_resgid; 1093 sb->s_flags = old_sb_flags; 1094 return err; 1095 } 1096 1097 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1098 { 1099 struct super_block *sb = dentry->d_sb; 1100 struct ext2_sb_info *sbi = EXT2_SB(sb); 1101 struct ext2_super_block *es = sbi->s_es; 1102 unsigned long overhead; 1103 int i; 1104 u64 fsid; 1105 1106 if (test_opt (sb, MINIX_DF)) 1107 overhead = 0; 1108 else { 1109 /* 1110 * Compute the overhead (FS structures) 1111 */ 1112 1113 /* 1114 * All of the blocks before first_data_block are 1115 * overhead 1116 */ 1117 overhead = le32_to_cpu(es->s_first_data_block); 1118 1119 /* 1120 * Add the overhead attributed to the superblock and 1121 * block group descriptors. If the sparse superblocks 1122 * feature is turned on, then not all groups have this. 1123 */ 1124 for (i = 0; i < sbi->s_groups_count; i++) 1125 overhead += ext2_bg_has_super(sb, i) + 1126 ext2_bg_num_gdb(sb, i); 1127 1128 /* 1129 * Every block group has an inode bitmap, a block 1130 * bitmap, and an inode table. 1131 */ 1132 overhead += (sbi->s_groups_count * 1133 (2 + sbi->s_itb_per_group)); 1134 } 1135 1136 buf->f_type = EXT2_SUPER_MAGIC; 1137 buf->f_bsize = sb->s_blocksize; 1138 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - overhead; 1139 buf->f_bfree = ext2_count_free_blocks(sb); 1140 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1141 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1142 buf->f_bavail = 0; 1143 buf->f_files = le32_to_cpu(es->s_inodes_count); 1144 buf->f_ffree = ext2_count_free_inodes(sb); 1145 buf->f_namelen = EXT2_NAME_LEN; 1146 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1147 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1148 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1149 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1150 return 0; 1151 } 1152 1153 static int ext2_get_sb(struct file_system_type *fs_type, 1154 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 1155 { 1156 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt); 1157 } 1158 1159 #ifdef CONFIG_QUOTA 1160 1161 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1162 * acquiring the locks... As quota files are never truncated and quota code 1163 * itself serializes the operations (and noone else should touch the files) 1164 * we don't have to be afraid of races */ 1165 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1166 size_t len, loff_t off) 1167 { 1168 struct inode *inode = sb_dqopt(sb)->files[type]; 1169 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1170 int err = 0; 1171 int offset = off & (sb->s_blocksize - 1); 1172 int tocopy; 1173 size_t toread; 1174 struct buffer_head tmp_bh; 1175 struct buffer_head *bh; 1176 loff_t i_size = i_size_read(inode); 1177 1178 if (off > i_size) 1179 return 0; 1180 if (off+len > i_size) 1181 len = i_size-off; 1182 toread = len; 1183 while (toread > 0) { 1184 tocopy = sb->s_blocksize - offset < toread ? 1185 sb->s_blocksize - offset : toread; 1186 1187 tmp_bh.b_state = 0; 1188 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1189 if (err) 1190 return err; 1191 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1192 memset(data, 0, tocopy); 1193 else { 1194 bh = sb_bread(sb, tmp_bh.b_blocknr); 1195 if (!bh) 1196 return -EIO; 1197 memcpy(data, bh->b_data+offset, tocopy); 1198 brelse(bh); 1199 } 1200 offset = 0; 1201 toread -= tocopy; 1202 data += tocopy; 1203 blk++; 1204 } 1205 return len; 1206 } 1207 1208 /* Write to quotafile */ 1209 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1210 const char *data, size_t len, loff_t off) 1211 { 1212 struct inode *inode = sb_dqopt(sb)->files[type]; 1213 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1214 int err = 0; 1215 int offset = off & (sb->s_blocksize - 1); 1216 int tocopy; 1217 size_t towrite = len; 1218 struct buffer_head tmp_bh; 1219 struct buffer_head *bh; 1220 1221 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 1222 while (towrite > 0) { 1223 tocopy = sb->s_blocksize - offset < towrite ? 1224 sb->s_blocksize - offset : towrite; 1225 1226 tmp_bh.b_state = 0; 1227 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1228 if (err) 1229 goto out; 1230 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1231 bh = sb_bread(sb, tmp_bh.b_blocknr); 1232 else 1233 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1234 if (!bh) { 1235 err = -EIO; 1236 goto out; 1237 } 1238 lock_buffer(bh); 1239 memcpy(bh->b_data+offset, data, tocopy); 1240 flush_dcache_page(bh->b_page); 1241 set_buffer_uptodate(bh); 1242 mark_buffer_dirty(bh); 1243 unlock_buffer(bh); 1244 brelse(bh); 1245 offset = 0; 1246 towrite -= tocopy; 1247 data += tocopy; 1248 blk++; 1249 } 1250 out: 1251 if (len == towrite) 1252 return err; 1253 if (inode->i_size < off+len-towrite) 1254 i_size_write(inode, off+len-towrite); 1255 inode->i_version++; 1256 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1257 mark_inode_dirty(inode); 1258 mutex_unlock(&inode->i_mutex); 1259 return len - towrite; 1260 } 1261 1262 #endif 1263 1264 static struct file_system_type ext2_fs_type = { 1265 .owner = THIS_MODULE, 1266 .name = "ext2", 1267 .get_sb = ext2_get_sb, 1268 .kill_sb = kill_block_super, 1269 .fs_flags = FS_REQUIRES_DEV, 1270 }; 1271 1272 static int __init init_ext2_fs(void) 1273 { 1274 int err = init_ext2_xattr(); 1275 if (err) 1276 return err; 1277 err = init_inodecache(); 1278 if (err) 1279 goto out1; 1280 err = register_filesystem(&ext2_fs_type); 1281 if (err) 1282 goto out; 1283 return 0; 1284 out: 1285 destroy_inodecache(); 1286 out1: 1287 exit_ext2_xattr(); 1288 return err; 1289 } 1290 1291 static void __exit exit_ext2_fs(void) 1292 { 1293 unregister_filesystem(&ext2_fs_type); 1294 destroy_inodecache(); 1295 exit_ext2_xattr(); 1296 } 1297 1298 module_init(init_ext2_fs) 1299 module_exit(exit_ext2_fs) 1300