1 /* 2 * linux/fs/ext4/ialloc.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 * BSD ufs-inspired inode and directory allocation by 10 * Stephen Tweedie (sct@redhat.com), 1993 11 * Big-endian to little-endian byte-swapping/bitmaps by 12 * David S. Miller (davem@caip.rutgers.edu), 1995 13 */ 14 15 #include <linux/time.h> 16 #include <linux/fs.h> 17 #include <linux/jbd2.h> 18 #include <linux/ext4_fs.h> 19 #include <linux/ext4_jbd2.h> 20 #include <linux/stat.h> 21 #include <linux/string.h> 22 #include <linux/quotaops.h> 23 #include <linux/buffer_head.h> 24 #include <linux/random.h> 25 #include <linux/bitops.h> 26 #include <linux/blkdev.h> 27 #include <asm/byteorder.h> 28 29 #include "xattr.h" 30 #include "acl.h" 31 #include "group.h" 32 33 /* 34 * ialloc.c contains the inodes allocation and deallocation routines 35 */ 36 37 /* 38 * The free inodes are managed by bitmaps. A file system contains several 39 * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap 40 * block for inodes, N blocks for the inode table and data blocks. 41 * 42 * The file system contains group descriptors which are located after the 43 * super block. Each descriptor contains the number of the bitmap block and 44 * the free blocks count in the block. 45 */ 46 47 /* 48 * To avoid calling the atomic setbit hundreds or thousands of times, we only 49 * need to use it within a single byte (to ensure we get endianness right). 50 * We can use memset for the rest of the bitmap as there are no other users. 51 */ 52 void mark_bitmap_end(int start_bit, int end_bit, char *bitmap) 53 { 54 int i; 55 56 if (start_bit >= end_bit) 57 return; 58 59 ext4_debug("mark end bits +%d through +%d used\n", start_bit, end_bit); 60 for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++) 61 ext4_set_bit(i, bitmap); 62 if (i < end_bit) 63 memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3); 64 } 65 66 /* Initializes an uninitialized inode bitmap */ 67 unsigned ext4_init_inode_bitmap(struct super_block *sb, 68 struct buffer_head *bh, int block_group, 69 struct ext4_group_desc *gdp) 70 { 71 struct ext4_sb_info *sbi = EXT4_SB(sb); 72 73 J_ASSERT_BH(bh, buffer_locked(bh)); 74 75 /* If checksum is bad mark all blocks and inodes use to prevent 76 * allocation, essentially implementing a per-group read-only flag. */ 77 if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) { 78 ext4_error(sb, __FUNCTION__, "Checksum bad for group %u\n", 79 block_group); 80 gdp->bg_free_blocks_count = 0; 81 gdp->bg_free_inodes_count = 0; 82 gdp->bg_itable_unused = 0; 83 memset(bh->b_data, 0xff, sb->s_blocksize); 84 return 0; 85 } 86 87 memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8); 88 mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), EXT4_BLOCKS_PER_GROUP(sb), 89 bh->b_data); 90 91 return EXT4_INODES_PER_GROUP(sb); 92 } 93 94 /* 95 * Read the inode allocation bitmap for a given block_group, reading 96 * into the specified slot in the superblock's bitmap cache. 97 * 98 * Return buffer_head of bitmap on success or NULL. 99 */ 100 static struct buffer_head * 101 read_inode_bitmap(struct super_block * sb, unsigned long block_group) 102 { 103 struct ext4_group_desc *desc; 104 struct buffer_head *bh = NULL; 105 106 desc = ext4_get_group_desc(sb, block_group, NULL); 107 if (!desc) 108 goto error_out; 109 if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) { 110 bh = sb_getblk(sb, ext4_inode_bitmap(sb, desc)); 111 if (!buffer_uptodate(bh)) { 112 lock_buffer(bh); 113 if (!buffer_uptodate(bh)) { 114 ext4_init_inode_bitmap(sb, bh, block_group, 115 desc); 116 set_buffer_uptodate(bh); 117 } 118 unlock_buffer(bh); 119 } 120 } else { 121 bh = sb_bread(sb, ext4_inode_bitmap(sb, desc)); 122 } 123 if (!bh) 124 ext4_error(sb, "read_inode_bitmap", 125 "Cannot read inode bitmap - " 126 "block_group = %lu, inode_bitmap = %llu", 127 block_group, ext4_inode_bitmap(sb, desc)); 128 error_out: 129 return bh; 130 } 131 132 /* 133 * NOTE! When we get the inode, we're the only people 134 * that have access to it, and as such there are no 135 * race conditions we have to worry about. The inode 136 * is not on the hash-lists, and it cannot be reached 137 * through the filesystem because the directory entry 138 * has been deleted earlier. 139 * 140 * HOWEVER: we must make sure that we get no aliases, 141 * which means that we have to call "clear_inode()" 142 * _before_ we mark the inode not in use in the inode 143 * bitmaps. Otherwise a newly created file might use 144 * the same inode number (not actually the same pointer 145 * though), and then we'd have two inodes sharing the 146 * same inode number and space on the harddisk. 147 */ 148 void ext4_free_inode (handle_t *handle, struct inode * inode) 149 { 150 struct super_block * sb = inode->i_sb; 151 int is_directory; 152 unsigned long ino; 153 struct buffer_head *bitmap_bh = NULL; 154 struct buffer_head *bh2; 155 unsigned long block_group; 156 unsigned long bit; 157 struct ext4_group_desc * gdp; 158 struct ext4_super_block * es; 159 struct ext4_sb_info *sbi; 160 int fatal = 0, err; 161 162 if (atomic_read(&inode->i_count) > 1) { 163 printk ("ext4_free_inode: inode has count=%d\n", 164 atomic_read(&inode->i_count)); 165 return; 166 } 167 if (inode->i_nlink) { 168 printk ("ext4_free_inode: inode has nlink=%d\n", 169 inode->i_nlink); 170 return; 171 } 172 if (!sb) { 173 printk("ext4_free_inode: inode on nonexistent device\n"); 174 return; 175 } 176 sbi = EXT4_SB(sb); 177 178 ino = inode->i_ino; 179 ext4_debug ("freeing inode %lu\n", ino); 180 181 /* 182 * Note: we must free any quota before locking the superblock, 183 * as writing the quota to disk may need the lock as well. 184 */ 185 DQUOT_INIT(inode); 186 ext4_xattr_delete_inode(handle, inode); 187 DQUOT_FREE_INODE(inode); 188 DQUOT_DROP(inode); 189 190 is_directory = S_ISDIR(inode->i_mode); 191 192 /* Do this BEFORE marking the inode not in use or returning an error */ 193 clear_inode (inode); 194 195 es = EXT4_SB(sb)->s_es; 196 if (ino < EXT4_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) { 197 ext4_error (sb, "ext4_free_inode", 198 "reserved or nonexistent inode %lu", ino); 199 goto error_return; 200 } 201 block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb); 202 bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb); 203 bitmap_bh = read_inode_bitmap(sb, block_group); 204 if (!bitmap_bh) 205 goto error_return; 206 207 BUFFER_TRACE(bitmap_bh, "get_write_access"); 208 fatal = ext4_journal_get_write_access(handle, bitmap_bh); 209 if (fatal) 210 goto error_return; 211 212 /* Ok, now we can actually update the inode bitmaps.. */ 213 if (!ext4_clear_bit_atomic(sb_bgl_lock(sbi, block_group), 214 bit, bitmap_bh->b_data)) 215 ext4_error (sb, "ext4_free_inode", 216 "bit already cleared for inode %lu", ino); 217 else { 218 gdp = ext4_get_group_desc (sb, block_group, &bh2); 219 220 BUFFER_TRACE(bh2, "get_write_access"); 221 fatal = ext4_journal_get_write_access(handle, bh2); 222 if (fatal) goto error_return; 223 224 if (gdp) { 225 spin_lock(sb_bgl_lock(sbi, block_group)); 226 gdp->bg_free_inodes_count = cpu_to_le16( 227 le16_to_cpu(gdp->bg_free_inodes_count) + 1); 228 if (is_directory) 229 gdp->bg_used_dirs_count = cpu_to_le16( 230 le16_to_cpu(gdp->bg_used_dirs_count) - 1); 231 gdp->bg_checksum = ext4_group_desc_csum(sbi, 232 block_group, gdp); 233 spin_unlock(sb_bgl_lock(sbi, block_group)); 234 percpu_counter_inc(&sbi->s_freeinodes_counter); 235 if (is_directory) 236 percpu_counter_dec(&sbi->s_dirs_counter); 237 238 } 239 BUFFER_TRACE(bh2, "call ext4_journal_dirty_metadata"); 240 err = ext4_journal_dirty_metadata(handle, bh2); 241 if (!fatal) fatal = err; 242 } 243 BUFFER_TRACE(bitmap_bh, "call ext4_journal_dirty_metadata"); 244 err = ext4_journal_dirty_metadata(handle, bitmap_bh); 245 if (!fatal) 246 fatal = err; 247 sb->s_dirt = 1; 248 error_return: 249 brelse(bitmap_bh); 250 ext4_std_error(sb, fatal); 251 } 252 253 /* 254 * There are two policies for allocating an inode. If the new inode is 255 * a directory, then a forward search is made for a block group with both 256 * free space and a low directory-to-inode ratio; if that fails, then of 257 * the groups with above-average free space, that group with the fewest 258 * directories already is chosen. 259 * 260 * For other inodes, search forward from the parent directory\'s block 261 * group to find a free inode. 262 */ 263 static int find_group_dir(struct super_block *sb, struct inode *parent) 264 { 265 int ngroups = EXT4_SB(sb)->s_groups_count; 266 unsigned int freei, avefreei; 267 struct ext4_group_desc *desc, *best_desc = NULL; 268 int group, best_group = -1; 269 270 freei = percpu_counter_read_positive(&EXT4_SB(sb)->s_freeinodes_counter); 271 avefreei = freei / ngroups; 272 273 for (group = 0; group < ngroups; group++) { 274 desc = ext4_get_group_desc (sb, group, NULL); 275 if (!desc || !desc->bg_free_inodes_count) 276 continue; 277 if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei) 278 continue; 279 if (!best_desc || 280 (le16_to_cpu(desc->bg_free_blocks_count) > 281 le16_to_cpu(best_desc->bg_free_blocks_count))) { 282 best_group = group; 283 best_desc = desc; 284 } 285 } 286 return best_group; 287 } 288 289 /* 290 * Orlov's allocator for directories. 291 * 292 * We always try to spread first-level directories. 293 * 294 * If there are blockgroups with both free inodes and free blocks counts 295 * not worse than average we return one with smallest directory count. 296 * Otherwise we simply return a random group. 297 * 298 * For the rest rules look so: 299 * 300 * It's OK to put directory into a group unless 301 * it has too many directories already (max_dirs) or 302 * it has too few free inodes left (min_inodes) or 303 * it has too few free blocks left (min_blocks) or 304 * it's already running too large debt (max_debt). 305 * Parent's group is prefered, if it doesn't satisfy these 306 * conditions we search cyclically through the rest. If none 307 * of the groups look good we just look for a group with more 308 * free inodes than average (starting at parent's group). 309 * 310 * Debt is incremented each time we allocate a directory and decremented 311 * when we allocate an inode, within 0--255. 312 */ 313 314 #define INODE_COST 64 315 #define BLOCK_COST 256 316 317 static int find_group_orlov(struct super_block *sb, struct inode *parent) 318 { 319 int parent_group = EXT4_I(parent)->i_block_group; 320 struct ext4_sb_info *sbi = EXT4_SB(sb); 321 struct ext4_super_block *es = sbi->s_es; 322 int ngroups = sbi->s_groups_count; 323 int inodes_per_group = EXT4_INODES_PER_GROUP(sb); 324 unsigned int freei, avefreei; 325 ext4_fsblk_t freeb, avefreeb; 326 ext4_fsblk_t blocks_per_dir; 327 unsigned int ndirs; 328 int max_debt, max_dirs, min_inodes; 329 ext4_grpblk_t min_blocks; 330 int group = -1, i; 331 struct ext4_group_desc *desc; 332 333 freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter); 334 avefreei = freei / ngroups; 335 freeb = percpu_counter_read_positive(&sbi->s_freeblocks_counter); 336 avefreeb = freeb; 337 do_div(avefreeb, ngroups); 338 ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter); 339 340 if ((parent == sb->s_root->d_inode) || 341 (EXT4_I(parent)->i_flags & EXT4_TOPDIR_FL)) { 342 int best_ndir = inodes_per_group; 343 int best_group = -1; 344 345 get_random_bytes(&group, sizeof(group)); 346 parent_group = (unsigned)group % ngroups; 347 for (i = 0; i < ngroups; i++) { 348 group = (parent_group + i) % ngroups; 349 desc = ext4_get_group_desc (sb, group, NULL); 350 if (!desc || !desc->bg_free_inodes_count) 351 continue; 352 if (le16_to_cpu(desc->bg_used_dirs_count) >= best_ndir) 353 continue; 354 if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei) 355 continue; 356 if (le16_to_cpu(desc->bg_free_blocks_count) < avefreeb) 357 continue; 358 best_group = group; 359 best_ndir = le16_to_cpu(desc->bg_used_dirs_count); 360 } 361 if (best_group >= 0) 362 return best_group; 363 goto fallback; 364 } 365 366 blocks_per_dir = ext4_blocks_count(es) - freeb; 367 do_div(blocks_per_dir, ndirs); 368 369 max_dirs = ndirs / ngroups + inodes_per_group / 16; 370 min_inodes = avefreei - inodes_per_group / 4; 371 min_blocks = avefreeb - EXT4_BLOCKS_PER_GROUP(sb) / 4; 372 373 max_debt = EXT4_BLOCKS_PER_GROUP(sb); 374 max_debt /= max_t(int, blocks_per_dir, BLOCK_COST); 375 if (max_debt * INODE_COST > inodes_per_group) 376 max_debt = inodes_per_group / INODE_COST; 377 if (max_debt > 255) 378 max_debt = 255; 379 if (max_debt == 0) 380 max_debt = 1; 381 382 for (i = 0; i < ngroups; i++) { 383 group = (parent_group + i) % ngroups; 384 desc = ext4_get_group_desc (sb, group, NULL); 385 if (!desc || !desc->bg_free_inodes_count) 386 continue; 387 if (le16_to_cpu(desc->bg_used_dirs_count) >= max_dirs) 388 continue; 389 if (le16_to_cpu(desc->bg_free_inodes_count) < min_inodes) 390 continue; 391 if (le16_to_cpu(desc->bg_free_blocks_count) < min_blocks) 392 continue; 393 return group; 394 } 395 396 fallback: 397 for (i = 0; i < ngroups; i++) { 398 group = (parent_group + i) % ngroups; 399 desc = ext4_get_group_desc (sb, group, NULL); 400 if (!desc || !desc->bg_free_inodes_count) 401 continue; 402 if (le16_to_cpu(desc->bg_free_inodes_count) >= avefreei) 403 return group; 404 } 405 406 if (avefreei) { 407 /* 408 * The free-inodes counter is approximate, and for really small 409 * filesystems the above test can fail to find any blockgroups 410 */ 411 avefreei = 0; 412 goto fallback; 413 } 414 415 return -1; 416 } 417 418 static int find_group_other(struct super_block *sb, struct inode *parent) 419 { 420 int parent_group = EXT4_I(parent)->i_block_group; 421 int ngroups = EXT4_SB(sb)->s_groups_count; 422 struct ext4_group_desc *desc; 423 int group, i; 424 425 /* 426 * Try to place the inode in its parent directory 427 */ 428 group = parent_group; 429 desc = ext4_get_group_desc (sb, group, NULL); 430 if (desc && le16_to_cpu(desc->bg_free_inodes_count) && 431 le16_to_cpu(desc->bg_free_blocks_count)) 432 return group; 433 434 /* 435 * We're going to place this inode in a different blockgroup from its 436 * parent. We want to cause files in a common directory to all land in 437 * the same blockgroup. But we want files which are in a different 438 * directory which shares a blockgroup with our parent to land in a 439 * different blockgroup. 440 * 441 * So add our directory's i_ino into the starting point for the hash. 442 */ 443 group = (group + parent->i_ino) % ngroups; 444 445 /* 446 * Use a quadratic hash to find a group with a free inode and some free 447 * blocks. 448 */ 449 for (i = 1; i < ngroups; i <<= 1) { 450 group += i; 451 if (group >= ngroups) 452 group -= ngroups; 453 desc = ext4_get_group_desc (sb, group, NULL); 454 if (desc && le16_to_cpu(desc->bg_free_inodes_count) && 455 le16_to_cpu(desc->bg_free_blocks_count)) 456 return group; 457 } 458 459 /* 460 * That failed: try linear search for a free inode, even if that group 461 * has no free blocks. 462 */ 463 group = parent_group; 464 for (i = 0; i < ngroups; i++) { 465 if (++group >= ngroups) 466 group = 0; 467 desc = ext4_get_group_desc (sb, group, NULL); 468 if (desc && le16_to_cpu(desc->bg_free_inodes_count)) 469 return group; 470 } 471 472 return -1; 473 } 474 475 /* 476 * There are two policies for allocating an inode. If the new inode is 477 * a directory, then a forward search is made for a block group with both 478 * free space and a low directory-to-inode ratio; if that fails, then of 479 * the groups with above-average free space, that group with the fewest 480 * directories already is chosen. 481 * 482 * For other inodes, search forward from the parent directory's block 483 * group to find a free inode. 484 */ 485 struct inode *ext4_new_inode(handle_t *handle, struct inode * dir, int mode) 486 { 487 struct super_block *sb; 488 struct buffer_head *bitmap_bh = NULL; 489 struct buffer_head *bh2; 490 int group; 491 unsigned long ino = 0; 492 struct inode * inode; 493 struct ext4_group_desc * gdp = NULL; 494 struct ext4_super_block * es; 495 struct ext4_inode_info *ei; 496 struct ext4_sb_info *sbi; 497 int err = 0; 498 struct inode *ret; 499 int i, free = 0; 500 501 /* Cannot create files in a deleted directory */ 502 if (!dir || !dir->i_nlink) 503 return ERR_PTR(-EPERM); 504 505 sb = dir->i_sb; 506 inode = new_inode(sb); 507 if (!inode) 508 return ERR_PTR(-ENOMEM); 509 ei = EXT4_I(inode); 510 511 sbi = EXT4_SB(sb); 512 es = sbi->s_es; 513 if (S_ISDIR(mode)) { 514 if (test_opt (sb, OLDALLOC)) 515 group = find_group_dir(sb, dir); 516 else 517 group = find_group_orlov(sb, dir); 518 } else 519 group = find_group_other(sb, dir); 520 521 err = -ENOSPC; 522 if (group == -1) 523 goto out; 524 525 for (i = 0; i < sbi->s_groups_count; i++) { 526 err = -EIO; 527 528 gdp = ext4_get_group_desc(sb, group, &bh2); 529 if (!gdp) 530 goto fail; 531 532 brelse(bitmap_bh); 533 bitmap_bh = read_inode_bitmap(sb, group); 534 if (!bitmap_bh) 535 goto fail; 536 537 ino = 0; 538 539 repeat_in_this_group: 540 ino = ext4_find_next_zero_bit((unsigned long *) 541 bitmap_bh->b_data, EXT4_INODES_PER_GROUP(sb), ino); 542 if (ino < EXT4_INODES_PER_GROUP(sb)) { 543 544 BUFFER_TRACE(bitmap_bh, "get_write_access"); 545 err = ext4_journal_get_write_access(handle, bitmap_bh); 546 if (err) 547 goto fail; 548 549 if (!ext4_set_bit_atomic(sb_bgl_lock(sbi, group), 550 ino, bitmap_bh->b_data)) { 551 /* we won it */ 552 BUFFER_TRACE(bitmap_bh, 553 "call ext4_journal_dirty_metadata"); 554 err = ext4_journal_dirty_metadata(handle, 555 bitmap_bh); 556 if (err) 557 goto fail; 558 goto got; 559 } 560 /* we lost it */ 561 jbd2_journal_release_buffer(handle, bitmap_bh); 562 563 if (++ino < EXT4_INODES_PER_GROUP(sb)) 564 goto repeat_in_this_group; 565 } 566 567 /* 568 * This case is possible in concurrent environment. It is very 569 * rare. We cannot repeat the find_group_xxx() call because 570 * that will simply return the same blockgroup, because the 571 * group descriptor metadata has not yet been updated. 572 * So we just go onto the next blockgroup. 573 */ 574 if (++group == sbi->s_groups_count) 575 group = 0; 576 } 577 err = -ENOSPC; 578 goto out; 579 580 got: 581 ino++; 582 if ((group == 0 && ino < EXT4_FIRST_INO(sb)) || 583 ino > EXT4_INODES_PER_GROUP(sb)) { 584 ext4_error(sb, __FUNCTION__, 585 "reserved inode or inode > inodes count - " 586 "block_group = %d, inode=%lu", group, 587 ino + group * EXT4_INODES_PER_GROUP(sb)); 588 err = -EIO; 589 goto fail; 590 } 591 592 BUFFER_TRACE(bh2, "get_write_access"); 593 err = ext4_journal_get_write_access(handle, bh2); 594 if (err) goto fail; 595 596 /* We may have to initialize the block bitmap if it isn't already */ 597 if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM) && 598 gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { 599 struct buffer_head *block_bh = read_block_bitmap(sb, group); 600 601 BUFFER_TRACE(block_bh, "get block bitmap access"); 602 err = ext4_journal_get_write_access(handle, block_bh); 603 if (err) { 604 brelse(block_bh); 605 goto fail; 606 } 607 608 free = 0; 609 spin_lock(sb_bgl_lock(sbi, group)); 610 /* recheck and clear flag under lock if we still need to */ 611 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { 612 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT); 613 free = ext4_free_blocks_after_init(sb, group, gdp); 614 gdp->bg_free_blocks_count = cpu_to_le16(free); 615 } 616 spin_unlock(sb_bgl_lock(sbi, group)); 617 618 /* Don't need to dirty bitmap block if we didn't change it */ 619 if (free) { 620 BUFFER_TRACE(block_bh, "dirty block bitmap"); 621 err = ext4_journal_dirty_metadata(handle, block_bh); 622 } 623 624 brelse(block_bh); 625 if (err) 626 goto fail; 627 } 628 629 spin_lock(sb_bgl_lock(sbi, group)); 630 /* If we didn't allocate from within the initialized part of the inode 631 * table then we need to initialize up to this inode. */ 632 if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) { 633 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) { 634 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT); 635 636 /* When marking the block group with 637 * ~EXT4_BG_INODE_UNINIT we don't want to depend 638 * on the value of bg_itable_unsed even though 639 * mke2fs could have initialized the same for us. 640 * Instead we calculated the value below 641 */ 642 643 free = 0; 644 } else { 645 free = EXT4_INODES_PER_GROUP(sb) - 646 le16_to_cpu(gdp->bg_itable_unused); 647 } 648 649 /* 650 * Check the relative inode number against the last used 651 * relative inode number in this group. if it is greater 652 * we need to update the bg_itable_unused count 653 * 654 */ 655 if (ino > free) 656 gdp->bg_itable_unused = 657 cpu_to_le16(EXT4_INODES_PER_GROUP(sb) - ino); 658 } 659 660 gdp->bg_free_inodes_count = 661 cpu_to_le16(le16_to_cpu(gdp->bg_free_inodes_count) - 1); 662 if (S_ISDIR(mode)) { 663 gdp->bg_used_dirs_count = 664 cpu_to_le16(le16_to_cpu(gdp->bg_used_dirs_count) + 1); 665 } 666 gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); 667 spin_unlock(sb_bgl_lock(sbi, group)); 668 BUFFER_TRACE(bh2, "call ext4_journal_dirty_metadata"); 669 err = ext4_journal_dirty_metadata(handle, bh2); 670 if (err) goto fail; 671 672 percpu_counter_dec(&sbi->s_freeinodes_counter); 673 if (S_ISDIR(mode)) 674 percpu_counter_inc(&sbi->s_dirs_counter); 675 sb->s_dirt = 1; 676 677 inode->i_uid = current->fsuid; 678 if (test_opt (sb, GRPID)) 679 inode->i_gid = dir->i_gid; 680 else if (dir->i_mode & S_ISGID) { 681 inode->i_gid = dir->i_gid; 682 if (S_ISDIR(mode)) 683 mode |= S_ISGID; 684 } else 685 inode->i_gid = current->fsgid; 686 inode->i_mode = mode; 687 688 inode->i_ino = ino + group * EXT4_INODES_PER_GROUP(sb); 689 /* This is the optimal IO size (for stat), not the fs block size */ 690 inode->i_blocks = 0; 691 inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime = 692 ext4_current_time(inode); 693 694 memset(ei->i_data, 0, sizeof(ei->i_data)); 695 ei->i_dir_start_lookup = 0; 696 ei->i_disksize = 0; 697 698 ei->i_flags = EXT4_I(dir)->i_flags & ~EXT4_INDEX_FL; 699 if (S_ISLNK(mode)) 700 ei->i_flags &= ~(EXT4_IMMUTABLE_FL|EXT4_APPEND_FL); 701 /* dirsync only applies to directories */ 702 if (!S_ISDIR(mode)) 703 ei->i_flags &= ~EXT4_DIRSYNC_FL; 704 ei->i_file_acl = 0; 705 ei->i_dir_acl = 0; 706 ei->i_dtime = 0; 707 ei->i_block_alloc_info = NULL; 708 ei->i_block_group = group; 709 710 ext4_set_inode_flags(inode); 711 if (IS_DIRSYNC(inode)) 712 handle->h_sync = 1; 713 insert_inode_hash(inode); 714 spin_lock(&sbi->s_next_gen_lock); 715 inode->i_generation = sbi->s_next_generation++; 716 spin_unlock(&sbi->s_next_gen_lock); 717 718 ei->i_state = EXT4_STATE_NEW; 719 720 ei->i_extra_isize = EXT4_SB(sb)->s_want_extra_isize; 721 722 ret = inode; 723 if(DQUOT_ALLOC_INODE(inode)) { 724 err = -EDQUOT; 725 goto fail_drop; 726 } 727 728 err = ext4_init_acl(handle, inode, dir); 729 if (err) 730 goto fail_free_drop; 731 732 err = ext4_init_security(handle,inode, dir); 733 if (err) 734 goto fail_free_drop; 735 736 err = ext4_mark_inode_dirty(handle, inode); 737 if (err) { 738 ext4_std_error(sb, err); 739 goto fail_free_drop; 740 } 741 if (test_opt(sb, EXTENTS)) { 742 EXT4_I(inode)->i_flags |= EXT4_EXTENTS_FL; 743 ext4_ext_tree_init(handle, inode); 744 if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) { 745 err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh); 746 if (err) goto fail; 747 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS); 748 BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "call ext4_journal_dirty_metadata"); 749 err = ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh); 750 } 751 } 752 753 ext4_debug("allocating inode %lu\n", inode->i_ino); 754 goto really_out; 755 fail: 756 ext4_std_error(sb, err); 757 out: 758 iput(inode); 759 ret = ERR_PTR(err); 760 really_out: 761 brelse(bitmap_bh); 762 return ret; 763 764 fail_free_drop: 765 DQUOT_FREE_INODE(inode); 766 767 fail_drop: 768 DQUOT_DROP(inode); 769 inode->i_flags |= S_NOQUOTA; 770 inode->i_nlink = 0; 771 iput(inode); 772 brelse(bitmap_bh); 773 return ERR_PTR(err); 774 } 775 776 /* Verify that we are loading a valid orphan from disk */ 777 struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino) 778 { 779 unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count); 780 unsigned long block_group; 781 int bit; 782 struct buffer_head *bitmap_bh = NULL; 783 struct inode *inode = NULL; 784 785 /* Error cases - e2fsck has already cleaned up for us */ 786 if (ino > max_ino) { 787 ext4_warning(sb, __FUNCTION__, 788 "bad orphan ino %lu! e2fsck was run?", ino); 789 goto out; 790 } 791 792 block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb); 793 bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb); 794 bitmap_bh = read_inode_bitmap(sb, block_group); 795 if (!bitmap_bh) { 796 ext4_warning(sb, __FUNCTION__, 797 "inode bitmap error for orphan %lu", ino); 798 goto out; 799 } 800 801 /* Having the inode bit set should be a 100% indicator that this 802 * is a valid orphan (no e2fsck run on fs). Orphans also include 803 * inodes that were being truncated, so we can't check i_nlink==0. 804 */ 805 if (!ext4_test_bit(bit, bitmap_bh->b_data) || 806 !(inode = iget(sb, ino)) || is_bad_inode(inode) || 807 NEXT_ORPHAN(inode) > max_ino) { 808 ext4_warning(sb, __FUNCTION__, 809 "bad orphan inode %lu! e2fsck was run?", ino); 810 printk(KERN_NOTICE "ext4_test_bit(bit=%d, block=%llu) = %d\n", 811 bit, (unsigned long long)bitmap_bh->b_blocknr, 812 ext4_test_bit(bit, bitmap_bh->b_data)); 813 printk(KERN_NOTICE "inode=%p\n", inode); 814 if (inode) { 815 printk(KERN_NOTICE "is_bad_inode(inode)=%d\n", 816 is_bad_inode(inode)); 817 printk(KERN_NOTICE "NEXT_ORPHAN(inode)=%u\n", 818 NEXT_ORPHAN(inode)); 819 printk(KERN_NOTICE "max_ino=%lu\n", max_ino); 820 } 821 /* Avoid freeing blocks if we got a bad deleted inode */ 822 if (inode && inode->i_nlink == 0) 823 inode->i_blocks = 0; 824 iput(inode); 825 inode = NULL; 826 } 827 out: 828 brelse(bitmap_bh); 829 return inode; 830 } 831 832 unsigned long ext4_count_free_inodes (struct super_block * sb) 833 { 834 unsigned long desc_count; 835 struct ext4_group_desc *gdp; 836 int i; 837 #ifdef EXT4FS_DEBUG 838 struct ext4_super_block *es; 839 unsigned long bitmap_count, x; 840 struct buffer_head *bitmap_bh = NULL; 841 842 es = EXT4_SB(sb)->s_es; 843 desc_count = 0; 844 bitmap_count = 0; 845 gdp = NULL; 846 for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) { 847 gdp = ext4_get_group_desc (sb, i, NULL); 848 if (!gdp) 849 continue; 850 desc_count += le16_to_cpu(gdp->bg_free_inodes_count); 851 brelse(bitmap_bh); 852 bitmap_bh = read_inode_bitmap(sb, i); 853 if (!bitmap_bh) 854 continue; 855 856 x = ext4_count_free(bitmap_bh, EXT4_INODES_PER_GROUP(sb) / 8); 857 printk("group %d: stored = %d, counted = %lu\n", 858 i, le16_to_cpu(gdp->bg_free_inodes_count), x); 859 bitmap_count += x; 860 } 861 brelse(bitmap_bh); 862 printk("ext4_count_free_inodes: stored = %u, computed = %lu, %lu\n", 863 le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count); 864 return desc_count; 865 #else 866 desc_count = 0; 867 for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) { 868 gdp = ext4_get_group_desc (sb, i, NULL); 869 if (!gdp) 870 continue; 871 desc_count += le16_to_cpu(gdp->bg_free_inodes_count); 872 cond_resched(); 873 } 874 return desc_count; 875 #endif 876 } 877 878 /* Called at mount-time, super-block is locked */ 879 unsigned long ext4_count_dirs (struct super_block * sb) 880 { 881 unsigned long count = 0; 882 int i; 883 884 for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) { 885 struct ext4_group_desc *gdp = ext4_get_group_desc (sb, i, NULL); 886 if (!gdp) 887 continue; 888 count += le16_to_cpu(gdp->bg_used_dirs_count); 889 } 890 return count; 891 } 892 893