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_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == 164 SLAB_CTOR_CONSTRUCTOR) { 165 rwlock_init(&ei->i_meta_lock); 166 #ifdef CONFIG_EXT2_FS_XATTR 167 init_rwsem(&ei->xattr_sem); 168 #endif 169 inode_init_once(&ei->vfs_inode); 170 } 171 } 172 173 static int init_inodecache(void) 174 { 175 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", 176 sizeof(struct ext2_inode_info), 177 0, (SLAB_RECLAIM_ACCOUNT| 178 SLAB_MEM_SPREAD), 179 init_once, NULL); 180 if (ext2_inode_cachep == NULL) 181 return -ENOMEM; 182 return 0; 183 } 184 185 static void destroy_inodecache(void) 186 { 187 kmem_cache_destroy(ext2_inode_cachep); 188 } 189 190 static void ext2_clear_inode(struct inode *inode) 191 { 192 #ifdef CONFIG_EXT2_FS_POSIX_ACL 193 struct ext2_inode_info *ei = EXT2_I(inode); 194 195 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) { 196 posix_acl_release(ei->i_acl); 197 ei->i_acl = EXT2_ACL_NOT_CACHED; 198 } 199 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) { 200 posix_acl_release(ei->i_default_acl); 201 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 202 } 203 #endif 204 } 205 206 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs) 207 { 208 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb); 209 210 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID) 211 seq_puts(seq, ",grpid"); 212 213 #if defined(CONFIG_QUOTA) 214 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA) 215 seq_puts(seq, ",usrquota"); 216 217 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA) 218 seq_puts(seq, ",grpquota"); 219 #endif 220 221 #if defined(CONFIG_EXT2_FS_XIP) 222 if (sbi->s_mount_opt & EXT2_MOUNT_XIP) 223 seq_puts(seq, ",xip"); 224 #endif 225 226 return 0; 227 } 228 229 #ifdef CONFIG_QUOTA 230 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off); 231 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off); 232 #endif 233 234 static struct super_operations ext2_sops = { 235 .alloc_inode = ext2_alloc_inode, 236 .destroy_inode = ext2_destroy_inode, 237 .read_inode = ext2_read_inode, 238 .write_inode = ext2_write_inode, 239 .put_inode = ext2_put_inode, 240 .delete_inode = ext2_delete_inode, 241 .put_super = ext2_put_super, 242 .write_super = ext2_write_super, 243 .statfs = ext2_statfs, 244 .remount_fs = ext2_remount, 245 .clear_inode = ext2_clear_inode, 246 .show_options = ext2_show_options, 247 #ifdef CONFIG_QUOTA 248 .quota_read = ext2_quota_read, 249 .quota_write = ext2_quota_write, 250 #endif 251 }; 252 253 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp) 254 { 255 __u32 *objp = vobjp; 256 unsigned long ino = objp[0]; 257 __u32 generation = objp[1]; 258 struct inode *inode; 259 struct dentry *result; 260 261 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) 262 return ERR_PTR(-ESTALE); 263 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 264 return ERR_PTR(-ESTALE); 265 266 /* iget isn't really right if the inode is currently unallocated!! 267 * ext2_read_inode currently does appropriate checks, but 268 * it might be "neater" to call ext2_get_inode first and check 269 * if the inode is valid..... 270 */ 271 inode = iget(sb, ino); 272 if (inode == NULL) 273 return ERR_PTR(-ENOMEM); 274 if (is_bad_inode(inode) || 275 (generation && inode->i_generation != generation)) { 276 /* we didn't find the right inode.. */ 277 iput(inode); 278 return ERR_PTR(-ESTALE); 279 } 280 /* now to find a dentry. 281 * If possible, get a well-connected one 282 */ 283 result = d_alloc_anon(inode); 284 if (!result) { 285 iput(inode); 286 return ERR_PTR(-ENOMEM); 287 } 288 return result; 289 } 290 291 /* Yes, most of these are left as NULL!! 292 * A NULL value implies the default, which works with ext2-like file 293 * systems, but can be improved upon. 294 * Currently only get_parent is required. 295 */ 296 static struct export_operations ext2_export_ops = { 297 .get_parent = ext2_get_parent, 298 .get_dentry = ext2_get_dentry, 299 }; 300 301 static unsigned long get_sb_block(void **data) 302 { 303 unsigned long sb_block; 304 char *options = (char *) *data; 305 306 if (!options || strncmp(options, "sb=", 3) != 0) 307 return 1; /* Default location */ 308 options += 3; 309 sb_block = simple_strtoul(options, &options, 0); 310 if (*options && *options != ',') { 311 printk("EXT2-fs: Invalid sb specification: %s\n", 312 (char *) *data); 313 return 1; 314 } 315 if (*options == ',') 316 options++; 317 *data = (void *) options; 318 return sb_block; 319 } 320 321 enum { 322 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid, 323 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, 324 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, 325 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, 326 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, 327 Opt_usrquota, Opt_grpquota 328 }; 329 330 static match_table_t tokens = { 331 {Opt_bsd_df, "bsddf"}, 332 {Opt_minix_df, "minixdf"}, 333 {Opt_grpid, "grpid"}, 334 {Opt_grpid, "bsdgroups"}, 335 {Opt_nogrpid, "nogrpid"}, 336 {Opt_nogrpid, "sysvgroups"}, 337 {Opt_resgid, "resgid=%u"}, 338 {Opt_resuid, "resuid=%u"}, 339 {Opt_sb, "sb=%u"}, 340 {Opt_err_cont, "errors=continue"}, 341 {Opt_err_panic, "errors=panic"}, 342 {Opt_err_ro, "errors=remount-ro"}, 343 {Opt_nouid32, "nouid32"}, 344 {Opt_nocheck, "check=none"}, 345 {Opt_nocheck, "nocheck"}, 346 {Opt_debug, "debug"}, 347 {Opt_oldalloc, "oldalloc"}, 348 {Opt_orlov, "orlov"}, 349 {Opt_nobh, "nobh"}, 350 {Opt_user_xattr, "user_xattr"}, 351 {Opt_nouser_xattr, "nouser_xattr"}, 352 {Opt_acl, "acl"}, 353 {Opt_noacl, "noacl"}, 354 {Opt_xip, "xip"}, 355 {Opt_grpquota, "grpquota"}, 356 {Opt_ignore, "noquota"}, 357 {Opt_quota, "quota"}, 358 {Opt_usrquota, "usrquota"}, 359 {Opt_err, NULL} 360 }; 361 362 static int parse_options (char * options, 363 struct ext2_sb_info *sbi) 364 { 365 char * p; 366 substring_t args[MAX_OPT_ARGS]; 367 int option; 368 369 if (!options) 370 return 1; 371 372 while ((p = strsep (&options, ",")) != NULL) { 373 int token; 374 if (!*p) 375 continue; 376 377 token = match_token(p, tokens, args); 378 switch (token) { 379 case Opt_bsd_df: 380 clear_opt (sbi->s_mount_opt, MINIX_DF); 381 break; 382 case Opt_minix_df: 383 set_opt (sbi->s_mount_opt, MINIX_DF); 384 break; 385 case Opt_grpid: 386 set_opt (sbi->s_mount_opt, GRPID); 387 break; 388 case Opt_nogrpid: 389 clear_opt (sbi->s_mount_opt, GRPID); 390 break; 391 case Opt_resuid: 392 if (match_int(&args[0], &option)) 393 return 0; 394 sbi->s_resuid = option; 395 break; 396 case Opt_resgid: 397 if (match_int(&args[0], &option)) 398 return 0; 399 sbi->s_resgid = option; 400 break; 401 case Opt_sb: 402 /* handled by get_sb_block() instead of here */ 403 /* *sb_block = match_int(&args[0]); */ 404 break; 405 case Opt_err_panic: 406 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 407 clear_opt (sbi->s_mount_opt, ERRORS_RO); 408 set_opt (sbi->s_mount_opt, ERRORS_PANIC); 409 break; 410 case Opt_err_ro: 411 clear_opt (sbi->s_mount_opt, ERRORS_CONT); 412 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 413 set_opt (sbi->s_mount_opt, ERRORS_RO); 414 break; 415 case Opt_err_cont: 416 clear_opt (sbi->s_mount_opt, ERRORS_RO); 417 clear_opt (sbi->s_mount_opt, ERRORS_PANIC); 418 set_opt (sbi->s_mount_opt, ERRORS_CONT); 419 break; 420 case Opt_nouid32: 421 set_opt (sbi->s_mount_opt, NO_UID32); 422 break; 423 case Opt_nocheck: 424 clear_opt (sbi->s_mount_opt, CHECK); 425 break; 426 case Opt_debug: 427 set_opt (sbi->s_mount_opt, DEBUG); 428 break; 429 case Opt_oldalloc: 430 set_opt (sbi->s_mount_opt, OLDALLOC); 431 break; 432 case Opt_orlov: 433 clear_opt (sbi->s_mount_opt, OLDALLOC); 434 break; 435 case Opt_nobh: 436 set_opt (sbi->s_mount_opt, NOBH); 437 break; 438 #ifdef CONFIG_EXT2_FS_XATTR 439 case Opt_user_xattr: 440 set_opt (sbi->s_mount_opt, XATTR_USER); 441 break; 442 case Opt_nouser_xattr: 443 clear_opt (sbi->s_mount_opt, XATTR_USER); 444 break; 445 #else 446 case Opt_user_xattr: 447 case Opt_nouser_xattr: 448 printk("EXT2 (no)user_xattr options not supported\n"); 449 break; 450 #endif 451 #ifdef CONFIG_EXT2_FS_POSIX_ACL 452 case Opt_acl: 453 set_opt(sbi->s_mount_opt, POSIX_ACL); 454 break; 455 case Opt_noacl: 456 clear_opt(sbi->s_mount_opt, POSIX_ACL); 457 break; 458 #else 459 case Opt_acl: 460 case Opt_noacl: 461 printk("EXT2 (no)acl options not supported\n"); 462 break; 463 #endif 464 case Opt_xip: 465 #ifdef CONFIG_EXT2_FS_XIP 466 set_opt (sbi->s_mount_opt, XIP); 467 #else 468 printk("EXT2 xip option not supported\n"); 469 #endif 470 break; 471 472 #if defined(CONFIG_QUOTA) 473 case Opt_quota: 474 case Opt_usrquota: 475 set_opt(sbi->s_mount_opt, USRQUOTA); 476 break; 477 478 case Opt_grpquota: 479 set_opt(sbi->s_mount_opt, GRPQUOTA); 480 break; 481 #else 482 case Opt_quota: 483 case Opt_usrquota: 484 case Opt_grpquota: 485 printk(KERN_ERR 486 "EXT2-fs: quota operations not supported.\n"); 487 488 break; 489 #endif 490 491 case Opt_ignore: 492 break; 493 default: 494 return 0; 495 } 496 } 497 return 1; 498 } 499 500 static int ext2_setup_super (struct super_block * sb, 501 struct ext2_super_block * es, 502 int read_only) 503 { 504 int res = 0; 505 struct ext2_sb_info *sbi = EXT2_SB(sb); 506 507 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { 508 printk ("EXT2-fs warning: revision level too high, " 509 "forcing read-only mode\n"); 510 res = MS_RDONLY; 511 } 512 if (read_only) 513 return res; 514 if (!(sbi->s_mount_state & EXT2_VALID_FS)) 515 printk ("EXT2-fs warning: mounting unchecked fs, " 516 "running e2fsck is recommended\n"); 517 else if ((sbi->s_mount_state & EXT2_ERROR_FS)) 518 printk ("EXT2-fs warning: mounting fs with errors, " 519 "running e2fsck is recommended\n"); 520 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && 521 le16_to_cpu(es->s_mnt_count) >= 522 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) 523 printk ("EXT2-fs warning: maximal mount count reached, " 524 "running e2fsck is recommended\n"); 525 else if (le32_to_cpu(es->s_checkinterval) && 526 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds())) 527 printk ("EXT2-fs warning: checktime reached, " 528 "running e2fsck is recommended\n"); 529 if (!le16_to_cpu(es->s_max_mnt_count)) 530 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); 531 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1); 532 ext2_write_super(sb); 533 if (test_opt (sb, DEBUG)) 534 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, " 535 "bpg=%lu, ipg=%lu, mo=%04lx]\n", 536 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize, 537 sbi->s_frag_size, 538 sbi->s_groups_count, 539 EXT2_BLOCKS_PER_GROUP(sb), 540 EXT2_INODES_PER_GROUP(sb), 541 sbi->s_mount_opt); 542 return res; 543 } 544 545 static int ext2_check_descriptors (struct super_block * sb) 546 { 547 int i; 548 int desc_block = 0; 549 struct ext2_sb_info *sbi = EXT2_SB(sb); 550 unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block); 551 unsigned long last_block; 552 struct ext2_group_desc * gdp = NULL; 553 554 ext2_debug ("Checking group descriptors"); 555 556 for (i = 0; i < sbi->s_groups_count; i++) 557 { 558 if (i == sbi->s_groups_count - 1) 559 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1; 560 else 561 last_block = first_block + 562 (EXT2_BLOCKS_PER_GROUP(sb) - 1); 563 564 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0) 565 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data; 566 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block || 567 le32_to_cpu(gdp->bg_block_bitmap) > last_block) 568 { 569 ext2_error (sb, "ext2_check_descriptors", 570 "Block bitmap for group %d" 571 " not in group (block %lu)!", 572 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap)); 573 return 0; 574 } 575 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block || 576 le32_to_cpu(gdp->bg_inode_bitmap) > last_block) 577 { 578 ext2_error (sb, "ext2_check_descriptors", 579 "Inode bitmap for group %d" 580 " not in group (block %lu)!", 581 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap)); 582 return 0; 583 } 584 if (le32_to_cpu(gdp->bg_inode_table) < first_block || 585 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group > 586 last_block) 587 { 588 ext2_error (sb, "ext2_check_descriptors", 589 "Inode table for group %d" 590 " not in group (block %lu)!", 591 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table)); 592 return 0; 593 } 594 first_block += EXT2_BLOCKS_PER_GROUP(sb); 595 gdp++; 596 } 597 return 1; 598 } 599 600 #define log2(n) ffz(~(n)) 601 602 /* 603 * Maximal file size. There is a direct, and {,double-,triple-}indirect 604 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. 605 * We need to be 1 filesystem block less than the 2^32 sector limit. 606 */ 607 static loff_t ext2_max_size(int bits) 608 { 609 loff_t res = EXT2_NDIR_BLOCKS; 610 /* This constant is calculated to be the largest file size for a 611 * dense, 4k-blocksize file such that the total number of 612 * sectors in the file, including data and all indirect blocks, 613 * does not exceed 2^32. */ 614 const loff_t upper_limit = 0x1ff7fffd000LL; 615 616 res += 1LL << (bits-2); 617 res += 1LL << (2*(bits-2)); 618 res += 1LL << (3*(bits-2)); 619 res <<= bits; 620 if (res > upper_limit) 621 res = upper_limit; 622 return res; 623 } 624 625 static unsigned long descriptor_loc(struct super_block *sb, 626 unsigned long logic_sb_block, 627 int nr) 628 { 629 struct ext2_sb_info *sbi = EXT2_SB(sb); 630 unsigned long bg, first_data_block, first_meta_bg; 631 int has_super = 0; 632 633 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block); 634 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg); 635 636 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) || 637 nr < first_meta_bg) 638 return (logic_sb_block + nr + 1); 639 bg = sbi->s_desc_per_block * nr; 640 if (ext2_bg_has_super(sb, bg)) 641 has_super = 1; 642 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group)); 643 } 644 645 static int ext2_fill_super(struct super_block *sb, void *data, int silent) 646 { 647 struct buffer_head * bh; 648 struct ext2_sb_info * sbi; 649 struct ext2_super_block * es; 650 struct inode *root; 651 unsigned long block; 652 unsigned long sb_block = get_sb_block(&data); 653 unsigned long logic_sb_block; 654 unsigned long offset = 0; 655 unsigned long def_mount_opts; 656 int blocksize = BLOCK_SIZE; 657 int db_count; 658 int i, j; 659 __le32 features; 660 661 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); 662 if (!sbi) 663 return -ENOMEM; 664 sb->s_fs_info = sbi; 665 666 /* 667 * See what the current blocksize for the device is, and 668 * use that as the blocksize. Otherwise (or if the blocksize 669 * is smaller than the default) use the default. 670 * This is important for devices that have a hardware 671 * sectorsize that is larger than the default. 672 */ 673 blocksize = sb_min_blocksize(sb, BLOCK_SIZE); 674 if (!blocksize) { 675 printk ("EXT2-fs: unable to set blocksize\n"); 676 goto failed_sbi; 677 } 678 679 /* 680 * If the superblock doesn't start on a hardware sector boundary, 681 * calculate the offset. 682 */ 683 if (blocksize != BLOCK_SIZE) { 684 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 685 offset = (sb_block*BLOCK_SIZE) % blocksize; 686 } else { 687 logic_sb_block = sb_block; 688 } 689 690 if (!(bh = sb_bread(sb, logic_sb_block))) { 691 printk ("EXT2-fs: unable to read superblock\n"); 692 goto failed_sbi; 693 } 694 /* 695 * Note: s_es must be initialized as soon as possible because 696 * some ext2 macro-instructions depend on its value 697 */ 698 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 699 sbi->s_es = es; 700 sb->s_magic = le16_to_cpu(es->s_magic); 701 702 if (sb->s_magic != EXT2_SUPER_MAGIC) 703 goto cantfind_ext2; 704 705 /* Set defaults before we parse the mount options */ 706 def_mount_opts = le32_to_cpu(es->s_default_mount_opts); 707 if (def_mount_opts & EXT2_DEFM_DEBUG) 708 set_opt(sbi->s_mount_opt, DEBUG); 709 if (def_mount_opts & EXT2_DEFM_BSDGROUPS) 710 set_opt(sbi->s_mount_opt, GRPID); 711 if (def_mount_opts & EXT2_DEFM_UID16) 712 set_opt(sbi->s_mount_opt, NO_UID32); 713 if (def_mount_opts & EXT2_DEFM_XATTR_USER) 714 set_opt(sbi->s_mount_opt, XATTR_USER); 715 if (def_mount_opts & EXT2_DEFM_ACL) 716 set_opt(sbi->s_mount_opt, POSIX_ACL); 717 718 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC) 719 set_opt(sbi->s_mount_opt, ERRORS_PANIC); 720 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO) 721 set_opt(sbi->s_mount_opt, ERRORS_RO); 722 else 723 set_opt(sbi->s_mount_opt, ERRORS_CONT); 724 725 sbi->s_resuid = le16_to_cpu(es->s_def_resuid); 726 sbi->s_resgid = le16_to_cpu(es->s_def_resgid); 727 728 if (!parse_options ((char *) data, sbi)) 729 goto failed_mount; 730 731 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 732 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? 733 MS_POSIXACL : 0); 734 735 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset 736 EXT2_MOUNT_XIP if not */ 737 738 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && 739 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || 740 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || 741 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) 742 printk("EXT2-fs warning: feature flags set on rev 0 fs, " 743 "running e2fsck is recommended\n"); 744 /* 745 * Check feature flags regardless of the revision level, since we 746 * previously didn't change the revision level when setting the flags, 747 * so there is a chance incompat flags are set on a rev 0 filesystem. 748 */ 749 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP); 750 if (features) { 751 printk("EXT2-fs: %s: couldn't mount because of " 752 "unsupported optional features (%x).\n", 753 sb->s_id, le32_to_cpu(features)); 754 goto failed_mount; 755 } 756 if (!(sb->s_flags & MS_RDONLY) && 757 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ 758 printk("EXT2-fs: %s: couldn't mount RDWR because of " 759 "unsupported optional features (%x).\n", 760 sb->s_id, le32_to_cpu(features)); 761 goto failed_mount; 762 } 763 764 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); 765 766 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) || 767 (sb->s_blocksize != blocksize))) { 768 if (!silent) 769 printk("XIP: Unsupported blocksize\n"); 770 goto failed_mount; 771 } 772 773 /* If the blocksize doesn't match, re-read the thing.. */ 774 if (sb->s_blocksize != blocksize) { 775 brelse(bh); 776 777 if (!sb_set_blocksize(sb, blocksize)) { 778 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); 779 goto failed_sbi; 780 } 781 782 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; 783 offset = (sb_block*BLOCK_SIZE) % blocksize; 784 bh = sb_bread(sb, logic_sb_block); 785 if(!bh) { 786 printk("EXT2-fs: Couldn't read superblock on " 787 "2nd try.\n"); 788 goto failed_sbi; 789 } 790 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); 791 sbi->s_es = es; 792 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) { 793 printk ("EXT2-fs: Magic mismatch, very weird !\n"); 794 goto failed_mount; 795 } 796 } 797 798 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); 799 800 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { 801 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; 802 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO; 803 } else { 804 sbi->s_inode_size = le16_to_cpu(es->s_inode_size); 805 sbi->s_first_ino = le32_to_cpu(es->s_first_ino); 806 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) || 807 (sbi->s_inode_size & (sbi->s_inode_size - 1)) || 808 (sbi->s_inode_size > blocksize)) { 809 printk ("EXT2-fs: unsupported inode size: %d\n", 810 sbi->s_inode_size); 811 goto failed_mount; 812 } 813 } 814 815 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE << 816 le32_to_cpu(es->s_log_frag_size); 817 if (sbi->s_frag_size == 0) 818 goto cantfind_ext2; 819 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size; 820 821 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group); 822 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group); 823 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); 824 825 if (EXT2_INODE_SIZE(sb) == 0) 826 goto cantfind_ext2; 827 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb); 828 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0) 829 goto cantfind_ext2; 830 sbi->s_itb_per_group = sbi->s_inodes_per_group / 831 sbi->s_inodes_per_block; 832 sbi->s_desc_per_block = sb->s_blocksize / 833 sizeof (struct ext2_group_desc); 834 sbi->s_sbh = bh; 835 sbi->s_mount_state = le16_to_cpu(es->s_state); 836 sbi->s_addr_per_block_bits = 837 log2 (EXT2_ADDR_PER_BLOCK(sb)); 838 sbi->s_desc_per_block_bits = 839 log2 (EXT2_DESC_PER_BLOCK(sb)); 840 841 if (sb->s_magic != EXT2_SUPER_MAGIC) 842 goto cantfind_ext2; 843 844 if (sb->s_blocksize != bh->b_size) { 845 if (!silent) 846 printk ("VFS: Unsupported blocksize on dev " 847 "%s.\n", sb->s_id); 848 goto failed_mount; 849 } 850 851 if (sb->s_blocksize != sbi->s_frag_size) { 852 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n", 853 sbi->s_frag_size, sb->s_blocksize); 854 goto failed_mount; 855 } 856 857 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) { 858 printk ("EXT2-fs: #blocks per group too big: %lu\n", 859 sbi->s_blocks_per_group); 860 goto failed_mount; 861 } 862 if (sbi->s_frags_per_group > sb->s_blocksize * 8) { 863 printk ("EXT2-fs: #fragments per group too big: %lu\n", 864 sbi->s_frags_per_group); 865 goto failed_mount; 866 } 867 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) { 868 printk ("EXT2-fs: #inodes per group too big: %lu\n", 869 sbi->s_inodes_per_group); 870 goto failed_mount; 871 } 872 873 if (EXT2_BLOCKS_PER_GROUP(sb) == 0) 874 goto cantfind_ext2; 875 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) - 876 le32_to_cpu(es->s_first_data_block) - 1) 877 / EXT2_BLOCKS_PER_GROUP(sb)) + 1; 878 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) / 879 EXT2_DESC_PER_BLOCK(sb); 880 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL); 881 if (sbi->s_group_desc == NULL) { 882 printk ("EXT2-fs: not enough memory\n"); 883 goto failed_mount; 884 } 885 bgl_lock_init(&sbi->s_blockgroup_lock); 886 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts), 887 GFP_KERNEL); 888 if (!sbi->s_debts) { 889 printk ("EXT2-fs: not enough memory\n"); 890 goto failed_mount_group_desc; 891 } 892 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts)); 893 for (i = 0; i < db_count; i++) { 894 block = descriptor_loc(sb, logic_sb_block, i); 895 sbi->s_group_desc[i] = sb_bread(sb, block); 896 if (!sbi->s_group_desc[i]) { 897 for (j = 0; j < i; j++) 898 brelse (sbi->s_group_desc[j]); 899 printk ("EXT2-fs: unable to read group descriptors\n"); 900 goto failed_mount_group_desc; 901 } 902 } 903 if (!ext2_check_descriptors (sb)) { 904 printk ("EXT2-fs: group descriptors corrupted!\n"); 905 goto failed_mount2; 906 } 907 sbi->s_gdb_count = db_count; 908 get_random_bytes(&sbi->s_next_generation, sizeof(u32)); 909 spin_lock_init(&sbi->s_next_gen_lock); 910 911 percpu_counter_init(&sbi->s_freeblocks_counter, 912 ext2_count_free_blocks(sb)); 913 percpu_counter_init(&sbi->s_freeinodes_counter, 914 ext2_count_free_inodes(sb)); 915 percpu_counter_init(&sbi->s_dirs_counter, 916 ext2_count_dirs(sb)); 917 /* 918 * set up enough so that it can read an inode 919 */ 920 sb->s_op = &ext2_sops; 921 sb->s_export_op = &ext2_export_ops; 922 sb->s_xattr = ext2_xattr_handlers; 923 root = iget(sb, EXT2_ROOT_INO); 924 sb->s_root = d_alloc_root(root); 925 if (!sb->s_root) { 926 iput(root); 927 printk(KERN_ERR "EXT2-fs: get root inode failed\n"); 928 goto failed_mount3; 929 } 930 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { 931 dput(sb->s_root); 932 sb->s_root = NULL; 933 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n"); 934 goto failed_mount3; 935 } 936 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) 937 ext2_warning(sb, __FUNCTION__, 938 "mounting ext3 filesystem as ext2"); 939 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); 940 return 0; 941 942 cantfind_ext2: 943 if (!silent) 944 printk("VFS: Can't find an ext2 filesystem on dev %s.\n", 945 sb->s_id); 946 goto failed_mount; 947 failed_mount3: 948 percpu_counter_destroy(&sbi->s_freeblocks_counter); 949 percpu_counter_destroy(&sbi->s_freeinodes_counter); 950 percpu_counter_destroy(&sbi->s_dirs_counter); 951 failed_mount2: 952 for (i = 0; i < db_count; i++) 953 brelse(sbi->s_group_desc[i]); 954 failed_mount_group_desc: 955 kfree(sbi->s_group_desc); 956 kfree(sbi->s_debts); 957 failed_mount: 958 brelse(bh); 959 failed_sbi: 960 sb->s_fs_info = NULL; 961 kfree(sbi); 962 return -EINVAL; 963 } 964 965 static void ext2_commit_super (struct super_block * sb, 966 struct ext2_super_block * es) 967 { 968 es->s_wtime = cpu_to_le32(get_seconds()); 969 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 970 sb->s_dirt = 0; 971 } 972 973 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es) 974 { 975 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 976 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 977 es->s_wtime = cpu_to_le32(get_seconds()); 978 mark_buffer_dirty(EXT2_SB(sb)->s_sbh); 979 sync_dirty_buffer(EXT2_SB(sb)->s_sbh); 980 sb->s_dirt = 0; 981 } 982 983 /* 984 * In the second extended file system, it is not necessary to 985 * write the super block since we use a mapping of the 986 * disk super block in a buffer. 987 * 988 * However, this function is still used to set the fs valid 989 * flags to 0. We need to set this flag to 0 since the fs 990 * may have been checked while mounted and e2fsck may have 991 * set s_state to EXT2_VALID_FS after some corrections. 992 */ 993 994 void ext2_write_super (struct super_block * sb) 995 { 996 struct ext2_super_block * es; 997 lock_kernel(); 998 if (!(sb->s_flags & MS_RDONLY)) { 999 es = EXT2_SB(sb)->s_es; 1000 1001 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) { 1002 ext2_debug ("setting valid to 0\n"); 1003 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & 1004 ~EXT2_VALID_FS); 1005 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb)); 1006 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb)); 1007 es->s_mtime = cpu_to_le32(get_seconds()); 1008 ext2_sync_super(sb, es); 1009 } else 1010 ext2_commit_super (sb, es); 1011 } 1012 sb->s_dirt = 0; 1013 unlock_kernel(); 1014 } 1015 1016 static int ext2_remount (struct super_block * sb, int * flags, char * data) 1017 { 1018 struct ext2_sb_info * sbi = EXT2_SB(sb); 1019 struct ext2_super_block * es; 1020 unsigned long old_mount_opt = sbi->s_mount_opt; 1021 struct ext2_mount_options old_opts; 1022 unsigned long old_sb_flags; 1023 int err; 1024 1025 /* Store the old options */ 1026 old_sb_flags = sb->s_flags; 1027 old_opts.s_mount_opt = sbi->s_mount_opt; 1028 old_opts.s_resuid = sbi->s_resuid; 1029 old_opts.s_resgid = sbi->s_resgid; 1030 1031 /* 1032 * Allow the "check" option to be passed as a remount option. 1033 */ 1034 if (!parse_options (data, sbi)) { 1035 err = -EINVAL; 1036 goto restore_opts; 1037 } 1038 1039 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | 1040 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); 1041 1042 es = sbi->s_es; 1043 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) != 1044 (old_mount_opt & EXT2_MOUNT_XIP)) && 1045 invalidate_inodes(sb)) 1046 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\ 1047 "xip remain in cache (no functional problem)"); 1048 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 1049 return 0; 1050 if (*flags & MS_RDONLY) { 1051 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || 1052 !(sbi->s_mount_state & EXT2_VALID_FS)) 1053 return 0; 1054 /* 1055 * OK, we are remounting a valid rw partition rdonly, so set 1056 * the rdonly flag and then mark the partition as valid again. 1057 */ 1058 es->s_state = cpu_to_le16(sbi->s_mount_state); 1059 es->s_mtime = cpu_to_le32(get_seconds()); 1060 } else { 1061 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, 1062 ~EXT2_FEATURE_RO_COMPAT_SUPP); 1063 if (ret) { 1064 printk("EXT2-fs: %s: couldn't remount RDWR because of " 1065 "unsupported optional features (%x).\n", 1066 sb->s_id, le32_to_cpu(ret)); 1067 err = -EROFS; 1068 goto restore_opts; 1069 } 1070 /* 1071 * Mounting a RDONLY partition read-write, so reread and 1072 * store the current valid flag. (It may have been changed 1073 * by e2fsck since we originally mounted the partition.) 1074 */ 1075 sbi->s_mount_state = le16_to_cpu(es->s_state); 1076 if (!ext2_setup_super (sb, es, 0)) 1077 sb->s_flags &= ~MS_RDONLY; 1078 } 1079 ext2_sync_super(sb, es); 1080 return 0; 1081 restore_opts: 1082 sbi->s_mount_opt = old_opts.s_mount_opt; 1083 sbi->s_resuid = old_opts.s_resuid; 1084 sbi->s_resgid = old_opts.s_resgid; 1085 sb->s_flags = old_sb_flags; 1086 return err; 1087 } 1088 1089 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) 1090 { 1091 struct super_block *sb = dentry->d_sb; 1092 struct ext2_sb_info *sbi = EXT2_SB(sb); 1093 struct ext2_super_block *es = sbi->s_es; 1094 unsigned long overhead; 1095 int i; 1096 u64 fsid; 1097 1098 if (test_opt (sb, MINIX_DF)) 1099 overhead = 0; 1100 else { 1101 /* 1102 * Compute the overhead (FS structures) 1103 */ 1104 1105 /* 1106 * All of the blocks before first_data_block are 1107 * overhead 1108 */ 1109 overhead = le32_to_cpu(es->s_first_data_block); 1110 1111 /* 1112 * Add the overhead attributed to the superblock and 1113 * block group descriptors. If the sparse superblocks 1114 * feature is turned on, then not all groups have this. 1115 */ 1116 for (i = 0; i < sbi->s_groups_count; i++) 1117 overhead += ext2_bg_has_super(sb, i) + 1118 ext2_bg_num_gdb(sb, i); 1119 1120 /* 1121 * Every block group has an inode bitmap, a block 1122 * bitmap, and an inode table. 1123 */ 1124 overhead += (sbi->s_groups_count * 1125 (2 + sbi->s_itb_per_group)); 1126 } 1127 1128 buf->f_type = EXT2_SUPER_MAGIC; 1129 buf->f_bsize = sb->s_blocksize; 1130 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - overhead; 1131 buf->f_bfree = ext2_count_free_blocks(sb); 1132 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count); 1133 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count)) 1134 buf->f_bavail = 0; 1135 buf->f_files = le32_to_cpu(es->s_inodes_count); 1136 buf->f_ffree = ext2_count_free_inodes(sb); 1137 buf->f_namelen = EXT2_NAME_LEN; 1138 fsid = le64_to_cpup((void *)es->s_uuid) ^ 1139 le64_to_cpup((void *)es->s_uuid + sizeof(u64)); 1140 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL; 1141 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL; 1142 return 0; 1143 } 1144 1145 static int ext2_get_sb(struct file_system_type *fs_type, 1146 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 1147 { 1148 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt); 1149 } 1150 1151 #ifdef CONFIG_QUOTA 1152 1153 /* Read data from quotafile - avoid pagecache and such because we cannot afford 1154 * acquiring the locks... As quota files are never truncated and quota code 1155 * itself serializes the operations (and noone else should touch the files) 1156 * we don't have to be afraid of races */ 1157 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, 1158 size_t len, loff_t off) 1159 { 1160 struct inode *inode = sb_dqopt(sb)->files[type]; 1161 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1162 int err = 0; 1163 int offset = off & (sb->s_blocksize - 1); 1164 int tocopy; 1165 size_t toread; 1166 struct buffer_head tmp_bh; 1167 struct buffer_head *bh; 1168 loff_t i_size = i_size_read(inode); 1169 1170 if (off > i_size) 1171 return 0; 1172 if (off+len > i_size) 1173 len = i_size-off; 1174 toread = len; 1175 while (toread > 0) { 1176 tocopy = sb->s_blocksize - offset < toread ? 1177 sb->s_blocksize - offset : toread; 1178 1179 tmp_bh.b_state = 0; 1180 err = ext2_get_block(inode, blk, &tmp_bh, 0); 1181 if (err) 1182 return err; 1183 if (!buffer_mapped(&tmp_bh)) /* A hole? */ 1184 memset(data, 0, tocopy); 1185 else { 1186 bh = sb_bread(sb, tmp_bh.b_blocknr); 1187 if (!bh) 1188 return -EIO; 1189 memcpy(data, bh->b_data+offset, tocopy); 1190 brelse(bh); 1191 } 1192 offset = 0; 1193 toread -= tocopy; 1194 data += tocopy; 1195 blk++; 1196 } 1197 return len; 1198 } 1199 1200 /* Write to quotafile */ 1201 static ssize_t ext2_quota_write(struct super_block *sb, int type, 1202 const char *data, size_t len, loff_t off) 1203 { 1204 struct inode *inode = sb_dqopt(sb)->files[type]; 1205 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb); 1206 int err = 0; 1207 int offset = off & (sb->s_blocksize - 1); 1208 int tocopy; 1209 size_t towrite = len; 1210 struct buffer_head tmp_bh; 1211 struct buffer_head *bh; 1212 1213 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA); 1214 while (towrite > 0) { 1215 tocopy = sb->s_blocksize - offset < towrite ? 1216 sb->s_blocksize - offset : towrite; 1217 1218 tmp_bh.b_state = 0; 1219 err = ext2_get_block(inode, blk, &tmp_bh, 1); 1220 if (err) 1221 goto out; 1222 if (offset || tocopy != EXT2_BLOCK_SIZE(sb)) 1223 bh = sb_bread(sb, tmp_bh.b_blocknr); 1224 else 1225 bh = sb_getblk(sb, tmp_bh.b_blocknr); 1226 if (!bh) { 1227 err = -EIO; 1228 goto out; 1229 } 1230 lock_buffer(bh); 1231 memcpy(bh->b_data+offset, data, tocopy); 1232 flush_dcache_page(bh->b_page); 1233 set_buffer_uptodate(bh); 1234 mark_buffer_dirty(bh); 1235 unlock_buffer(bh); 1236 brelse(bh); 1237 offset = 0; 1238 towrite -= tocopy; 1239 data += tocopy; 1240 blk++; 1241 } 1242 out: 1243 if (len == towrite) 1244 return err; 1245 if (inode->i_size < off+len-towrite) 1246 i_size_write(inode, off+len-towrite); 1247 inode->i_version++; 1248 inode->i_mtime = inode->i_ctime = CURRENT_TIME; 1249 mark_inode_dirty(inode); 1250 mutex_unlock(&inode->i_mutex); 1251 return len - towrite; 1252 } 1253 1254 #endif 1255 1256 static struct file_system_type ext2_fs_type = { 1257 .owner = THIS_MODULE, 1258 .name = "ext2", 1259 .get_sb = ext2_get_sb, 1260 .kill_sb = kill_block_super, 1261 .fs_flags = FS_REQUIRES_DEV, 1262 }; 1263 1264 static int __init init_ext2_fs(void) 1265 { 1266 int err = init_ext2_xattr(); 1267 if (err) 1268 return err; 1269 err = init_inodecache(); 1270 if (err) 1271 goto out1; 1272 err = register_filesystem(&ext2_fs_type); 1273 if (err) 1274 goto out; 1275 return 0; 1276 out: 1277 destroy_inodecache(); 1278 out1: 1279 exit_ext2_xattr(); 1280 return err; 1281 } 1282 1283 static void __exit exit_ext2_fs(void) 1284 { 1285 unregister_filesystem(&ext2_fs_type); 1286 destroy_inodecache(); 1287 exit_ext2_xattr(); 1288 } 1289 1290 module_init(init_ext2_fs) 1291 module_exit(exit_ext2_fs) 1292