extent.c revision 92e2d79cfbe67244eff8ded095491cba16e98dcc
1/* 2 * extent.c --- routines to implement extents support 3 * 4 * Copyright (C) 2007 Theodore Ts'o. 5 * 6 * %Begin-Header% 7 * This file may be redistributed under the terms of the GNU Library 8 * General Public License, version 2. 9 * %End-Header% 10 */ 11 12#include <stdio.h> 13#include <string.h> 14#if HAVE_UNISTD_H 15#include <unistd.h> 16#endif 17#if HAVE_ERRNO_H 18#include <errno.h> 19#endif 20#if HAVE_SYS_STAT_H 21#include <sys/stat.h> 22#endif 23#if HAVE_SYS_TYPES_H 24#include <sys/types.h> 25#endif 26 27#include "ext2_fs.h" 28#include "ext2fsP.h" 29#include "e2image.h" 30 31/* 32 * Definitions to be dropped in lib/ext2fs/ext2fs.h 33 */ 34 35/* 36 * Private definitions 37 */ 38 39struct extent_path { 40 char *buf; 41 int entries; 42 int max_entries; 43 int left; 44 int visit_num; 45 int flags; 46 blk64_t end_blk; 47 void *curr; 48}; 49 50 51struct ext2_extent_handle { 52 errcode_t magic; 53 ext2_filsys fs; 54 ext2_ino_t ino; 55 struct ext2_inode *inode; 56 int type; 57 int level; 58 int max_depth; 59 struct extent_path *path; 60}; 61 62struct ext2_extent_path { 63 errcode_t magic; 64 int leaf_height; 65 blk64_t lblk; 66}; 67 68/* 69 * Useful Debugging stuff 70 */ 71 72#ifdef DEBUG 73static void dbg_show_header(struct ext3_extent_header *eh) 74{ 75 printf("header: magic=%x entries=%u max=%u depth=%u generation=%u\n", 76 ext2fs_le16_to_cpu(eh->eh_magic), 77 ext2fs_le16_to_cpu(eh->eh_entries), 78 ext2fs_le16_to_cpu(eh->eh_max), 79 ext2fs_le16_to_cpu(eh->eh_depth), 80 ext2fs_le32_to_cpu(eh->eh_generation)); 81} 82 83static void dbg_show_index(struct ext3_extent_idx *ix) 84{ 85 printf("index: block=%u leaf=%u leaf_hi=%u unused=%u\n", 86 ext2fs_le32_to_cpu(ix->ei_block), 87 ext2fs_le32_to_cpu(ix->ei_leaf), 88 ext2fs_le16_to_cpu(ix->ei_leaf_hi), 89 ext2fs_le16_to_cpu(ix->ei_unused)); 90} 91 92static void dbg_show_extent(struct ext3_extent *ex) 93{ 94 printf("extent: block=%u-%u len=%u start=%u start_hi=%u\n", 95 ext2fs_le32_to_cpu(ex->ee_block), 96 ext2fs_le32_to_cpu(ex->ee_block) + 97 ext2fs_le16_to_cpu(ex->ee_len) - 1, 98 ext2fs_le16_to_cpu(ex->ee_len), 99 ext2fs_le32_to_cpu(ex->ee_start), 100 ext2fs_le16_to_cpu(ex->ee_start_hi)); 101} 102 103static void dbg_print_extent(char *desc, struct ext2fs_extent *extent) 104{ 105 if (desc) 106 printf("%s: ", desc); 107 printf("extent: lblk %llu--%llu, len %u, pblk %llu, flags: ", 108 extent->e_lblk, extent->e_lblk + extent->e_len - 1, 109 extent->e_len, extent->e_pblk); 110 if (extent->e_flags & EXT2_EXTENT_FLAGS_LEAF) 111 fputs("LEAF ", stdout); 112 if (extent->e_flags & EXT2_EXTENT_FLAGS_UNINIT) 113 fputs("UNINIT ", stdout); 114 if (extent->e_flags & EXT2_EXTENT_FLAGS_SECOND_VISIT) 115 fputs("2ND_VISIT ", stdout); 116 if (!extent->e_flags) 117 fputs("(none)", stdout); 118 fputc('\n', stdout); 119 120} 121 122#else 123#define dbg_show_header(eh) do { } while (0) 124#define dbg_show_index(ix) do { } while (0) 125#define dbg_show_extent(ex) do { } while (0) 126#define dbg_print_extent(desc, ex) do { } while (0) 127#endif 128 129/* 130 * Verify the extent header as being sane 131 */ 132errcode_t ext2fs_extent_header_verify(void *ptr, int size) 133{ 134 int eh_max, entry_size; 135 struct ext3_extent_header *eh = ptr; 136 137 dbg_show_header(eh); 138 if (ext2fs_le16_to_cpu(eh->eh_magic) != EXT3_EXT_MAGIC) 139 return EXT2_ET_EXTENT_HEADER_BAD; 140 if (ext2fs_le16_to_cpu(eh->eh_entries) > ext2fs_le16_to_cpu(eh->eh_max)) 141 return EXT2_ET_EXTENT_HEADER_BAD; 142 if (eh->eh_depth == 0) 143 entry_size = sizeof(struct ext3_extent); 144 else 145 entry_size = sizeof(struct ext3_extent_idx); 146 147 eh_max = (size - sizeof(*eh)) / entry_size; 148 /* Allow two extent-sized items at the end of the block, for 149 * ext4_extent_tail with checksum in the future. */ 150 if ((ext2fs_le16_to_cpu(eh->eh_max) > eh_max) || 151 (ext2fs_le16_to_cpu(eh->eh_max) < (eh_max - 2))) 152 return EXT2_ET_EXTENT_HEADER_BAD; 153 154 return 0; 155} 156 157 158/* 159 * Begin functions to handle an inode's extent information 160 */ 161extern void ext2fs_extent_free(ext2_extent_handle_t handle) 162{ 163 int i; 164 165 if (!handle) 166 return; 167 168 if (handle->inode) 169 ext2fs_free_mem(&handle->inode); 170 if (handle->path) { 171 for (i=1; i <= handle->max_depth; i++) { 172 if (handle->path[i].buf) 173 ext2fs_free_mem(&handle->path[i].buf); 174 } 175 ext2fs_free_mem(&handle->path); 176 } 177 ext2fs_free_mem(&handle); 178} 179 180extern errcode_t ext2fs_extent_open(ext2_filsys fs, ext2_ino_t ino, 181 ext2_extent_handle_t *ret_handle) 182{ 183 return ext2fs_extent_open2(fs, ino, NULL, ret_handle); 184} 185 186extern errcode_t ext2fs_extent_open2(ext2_filsys fs, ext2_ino_t ino, 187 struct ext2_inode *inode, 188 ext2_extent_handle_t *ret_handle) 189{ 190 struct ext2_extent_handle *handle; 191 errcode_t retval; 192 int i; 193 struct ext3_extent_header *eh; 194 195 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 196 197 if (!inode) 198 if ((ino == 0) || (ino > fs->super->s_inodes_count)) 199 return EXT2_ET_BAD_INODE_NUM; 200 201 retval = ext2fs_get_mem(sizeof(struct ext2_extent_handle), &handle); 202 if (retval) 203 return retval; 204 memset(handle, 0, sizeof(struct ext2_extent_handle)); 205 206 retval = ext2fs_get_mem(sizeof(struct ext2_inode), &handle->inode); 207 if (retval) 208 goto errout; 209 210 handle->ino = ino; 211 handle->fs = fs; 212 213 if (inode) { 214 memcpy(handle->inode, inode, sizeof(struct ext2_inode)); 215 } 216 else { 217 retval = ext2fs_read_inode(fs, ino, handle->inode); 218 if (retval) 219 goto errout; 220 } 221 222 eh = (struct ext3_extent_header *) &handle->inode->i_block[0]; 223 224 for (i=0; i < EXT2_N_BLOCKS; i++) 225 if (handle->inode->i_block[i]) 226 break; 227 if (i >= EXT2_N_BLOCKS) { 228 eh->eh_magic = ext2fs_cpu_to_le16(EXT3_EXT_MAGIC); 229 eh->eh_depth = 0; 230 eh->eh_entries = 0; 231 i = (sizeof(handle->inode->i_block) - sizeof(*eh)) / 232 sizeof(struct ext3_extent); 233 eh->eh_max = ext2fs_cpu_to_le16(i); 234 handle->inode->i_flags |= EXT4_EXTENTS_FL; 235 } 236 237 if (!(handle->inode->i_flags & EXT4_EXTENTS_FL)) { 238 retval = EXT2_ET_INODE_NOT_EXTENT; 239 goto errout; 240 } 241 242 retval = ext2fs_extent_header_verify(eh, sizeof(handle->inode->i_block)); 243 if (retval) 244 goto errout; 245 246 handle->max_depth = ext2fs_le16_to_cpu(eh->eh_depth); 247 handle->type = ext2fs_le16_to_cpu(eh->eh_magic); 248 249 retval = ext2fs_get_mem(((handle->max_depth+1) * 250 sizeof(struct extent_path)), 251 &handle->path); 252 memset(handle->path, 0, 253 (handle->max_depth+1) * sizeof(struct extent_path)); 254 handle->path[0].buf = (char *) handle->inode->i_block; 255 256 handle->path[0].left = handle->path[0].entries = 257 ext2fs_le16_to_cpu(eh->eh_entries); 258 handle->path[0].max_entries = ext2fs_le16_to_cpu(eh->eh_max); 259 handle->path[0].curr = 0; 260 handle->path[0].end_blk = 261 ((((__u64) handle->inode->i_size_high << 32) + 262 handle->inode->i_size + (fs->blocksize - 1)) 263 >> EXT2_BLOCK_SIZE_BITS(fs->super)); 264 handle->path[0].visit_num = 1; 265 handle->level = 0; 266 handle->magic = EXT2_ET_MAGIC_EXTENT_HANDLE; 267 268 *ret_handle = handle; 269 return 0; 270 271errout: 272 ext2fs_extent_free(handle); 273 return retval; 274} 275 276/* 277 * This function is responsible for (optionally) moving through the 278 * extent tree and then returning the current extent 279 */ 280errcode_t ext2fs_extent_get(ext2_extent_handle_t handle, 281 int flags, struct ext2fs_extent *extent) 282{ 283 struct extent_path *path, *newpath; 284 struct ext3_extent_header *eh; 285 struct ext3_extent_idx *ix = 0; 286 struct ext3_extent *ex; 287 errcode_t retval; 288 blk64_t blk; 289 blk64_t end_blk; 290 int orig_op, op; 291 292 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 293 294 if (!handle->path) 295 return EXT2_ET_NO_CURRENT_NODE; 296 297 orig_op = op = flags & EXT2_EXTENT_MOVE_MASK; 298 299retry: 300 path = handle->path + handle->level; 301 if ((orig_op == EXT2_EXTENT_NEXT) || 302 (orig_op == EXT2_EXTENT_NEXT_LEAF)) { 303 if (handle->level < handle->max_depth) { 304 /* interior node */ 305 if (path->visit_num == 0) { 306 path->visit_num++; 307 op = EXT2_EXTENT_DOWN; 308 } else if (path->left > 0) 309 op = EXT2_EXTENT_NEXT_SIB; 310 else if (handle->level > 0) 311 op = EXT2_EXTENT_UP; 312 else 313 return EXT2_ET_EXTENT_NO_NEXT; 314 } else { 315 /* leaf node */ 316 if (path->left > 0) 317 op = EXT2_EXTENT_NEXT_SIB; 318 else if (handle->level > 0) 319 op = EXT2_EXTENT_UP; 320 else 321 return EXT2_ET_EXTENT_NO_NEXT; 322 } 323 if (op != EXT2_EXTENT_NEXT_SIB) { 324#ifdef DEBUG_GET_EXTENT 325 printf("<<<< OP = %s\n", 326 (op == EXT2_EXTENT_DOWN) ? "down" : 327 ((op == EXT2_EXTENT_UP) ? "up" : "unknown")); 328#endif 329 } 330 } 331 332 if ((orig_op == EXT2_EXTENT_PREV) || 333 (orig_op == EXT2_EXTENT_PREV_LEAF)) { 334 if (handle->level < handle->max_depth) { 335 /* interior node */ 336 if (path->visit_num > 0 ) { 337 /* path->visit_num = 0; */ 338 op = EXT2_EXTENT_DOWN_AND_LAST; 339 } else if (path->left < path->entries-1) 340 op = EXT2_EXTENT_PREV_SIB; 341 else if (handle->level > 0) 342 op = EXT2_EXTENT_UP; 343 else 344 return EXT2_ET_EXTENT_NO_PREV; 345 } else { 346 /* leaf node */ 347 if (path->left < path->entries-1) 348 op = EXT2_EXTENT_PREV_SIB; 349 else if (handle->level > 0) 350 op = EXT2_EXTENT_UP; 351 else 352 return EXT2_ET_EXTENT_NO_PREV; 353 } 354 if (op != EXT2_EXTENT_PREV_SIB) { 355#ifdef DEBUG_GET_EXTENT 356 printf("<<<< OP = %s\n", 357 (op == EXT2_EXTENT_DOWN_AND_LAST) ? "down/last" : 358 ((op == EXT2_EXTENT_UP) ? "up" : "unknown")); 359#endif 360 } 361 } 362 363 if (orig_op == EXT2_EXTENT_LAST_LEAF) { 364 if ((handle->level < handle->max_depth) && 365 (path->left == 0)) 366 op = EXT2_EXTENT_DOWN; 367 else 368 op = EXT2_EXTENT_LAST_SIB; 369#ifdef DEBUG_GET_EXTENT 370 printf("<<<< OP = %s\n", 371 (op == EXT2_EXTENT_DOWN) ? "down" : "last_sib"); 372#endif 373 } 374 375 switch (op) { 376 case EXT2_EXTENT_CURRENT: 377 ix = path->curr; 378 break; 379 case EXT2_EXTENT_ROOT: 380 handle->level = 0; 381 path = handle->path + handle->level; 382 case EXT2_EXTENT_FIRST_SIB: 383 path->left = path->entries; 384 path->curr = 0; 385 case EXT2_EXTENT_NEXT_SIB: 386 if (path->left <= 0) 387 return EXT2_ET_EXTENT_NO_NEXT; 388 if (path->curr) { 389 ix = path->curr; 390 ix++; 391 } else { 392 eh = (struct ext3_extent_header *) path->buf; 393 ix = EXT_FIRST_INDEX(eh); 394 } 395 path->left--; 396 path->curr = ix; 397 path->visit_num = 0; 398 break; 399 case EXT2_EXTENT_PREV_SIB: 400 if (!path->curr || 401 path->left+1 >= path->entries) 402 return EXT2_ET_EXTENT_NO_PREV; 403 ix = path->curr; 404 ix--; 405 path->curr = ix; 406 path->left++; 407 if (handle->level < handle->max_depth) 408 path->visit_num = 1; 409 break; 410 case EXT2_EXTENT_LAST_SIB: 411 eh = (struct ext3_extent_header *) path->buf; 412 path->curr = EXT_LAST_EXTENT(eh); 413 ix = path->curr; 414 path->left = 0; 415 path->visit_num = 0; 416 break; 417 case EXT2_EXTENT_UP: 418 if (handle->level <= 0) 419 return EXT2_ET_EXTENT_NO_UP; 420 handle->level--; 421 path--; 422 ix = path->curr; 423 if ((orig_op == EXT2_EXTENT_PREV) || 424 (orig_op == EXT2_EXTENT_PREV_LEAF)) 425 path->visit_num = 0; 426 break; 427 case EXT2_EXTENT_DOWN: 428 case EXT2_EXTENT_DOWN_AND_LAST: 429 if (!path->curr ||(handle->level >= handle->max_depth)) 430 return EXT2_ET_EXTENT_NO_DOWN; 431 432 ix = path->curr; 433 newpath = path + 1; 434 if (!newpath->buf) { 435 retval = ext2fs_get_mem(handle->fs->blocksize, 436 &newpath->buf); 437 if (retval) 438 return retval; 439 } 440 blk = ext2fs_le32_to_cpu(ix->ei_leaf) + 441 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32); 442 if ((handle->fs->flags & EXT2_FLAG_IMAGE_FILE) && 443 (handle->fs->io != handle->fs->image_io)) 444 memset(newpath->buf, 0, handle->fs->blocksize); 445 else { 446 retval = io_channel_read_blk64(handle->fs->io, 447 blk, 1, newpath->buf); 448 if (retval) 449 return retval; 450 } 451 handle->level++; 452 453 eh = (struct ext3_extent_header *) newpath->buf; 454 455 retval = ext2fs_extent_header_verify(eh, handle->fs->blocksize); 456 if (retval) { 457 handle->level--; 458 return retval; 459 } 460 461 newpath->left = newpath->entries = 462 ext2fs_le16_to_cpu(eh->eh_entries); 463 newpath->max_entries = ext2fs_le16_to_cpu(eh->eh_max); 464 465 if (path->left > 0) { 466 ix++; 467 newpath->end_blk = ext2fs_le32_to_cpu(ix->ei_block); 468 } else 469 newpath->end_blk = path->end_blk; 470 471 path = newpath; 472 if (op == EXT2_EXTENT_DOWN) { 473 ix = EXT_FIRST_INDEX((struct ext3_extent_header *) eh); 474 path->curr = ix; 475 path->left = path->entries - 1; 476 path->visit_num = 0; 477 } else { 478 ix = EXT_LAST_INDEX((struct ext3_extent_header *) eh); 479 path->curr = ix; 480 path->left = 0; 481 if (handle->level < handle->max_depth) 482 path->visit_num = 1; 483 } 484#ifdef DEBUG_GET_EXTENT 485 printf("Down to level %d/%d, end_blk=%llu\n", 486 handle->level, handle->max_depth, 487 path->end_blk); 488#endif 489 break; 490 default: 491 return EXT2_ET_OP_NOT_SUPPORTED; 492 } 493 494 if (!ix) 495 return EXT2_ET_NO_CURRENT_NODE; 496 497 extent->e_flags = 0; 498#ifdef DEBUG_GET_EXTENT 499 printf("(Left %d)\n", path->left); 500#endif 501 502 if (handle->level == handle->max_depth) { 503 ex = (struct ext3_extent *) ix; 504 505 extent->e_pblk = ext2fs_le32_to_cpu(ex->ee_start) + 506 ((__u64) ext2fs_le16_to_cpu(ex->ee_start_hi) << 32); 507 extent->e_lblk = ext2fs_le32_to_cpu(ex->ee_block); 508 extent->e_len = ext2fs_le16_to_cpu(ex->ee_len); 509 extent->e_flags |= EXT2_EXTENT_FLAGS_LEAF; 510 if (extent->e_len > EXT_INIT_MAX_LEN) { 511 extent->e_len -= EXT_INIT_MAX_LEN; 512 extent->e_flags |= EXT2_EXTENT_FLAGS_UNINIT; 513 } 514 } else { 515 extent->e_pblk = ext2fs_le32_to_cpu(ix->ei_leaf) + 516 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32); 517 extent->e_lblk = ext2fs_le32_to_cpu(ix->ei_block); 518 if (path->left > 0) { 519 ix++; 520 end_blk = ext2fs_le32_to_cpu(ix->ei_block); 521 } else 522 end_blk = path->end_blk; 523 524 extent->e_len = end_blk - extent->e_lblk; 525 } 526 if (path->visit_num) 527 extent->e_flags |= EXT2_EXTENT_FLAGS_SECOND_VISIT; 528 529 if (((orig_op == EXT2_EXTENT_NEXT_LEAF) || 530 (orig_op == EXT2_EXTENT_PREV_LEAF)) && 531 (handle->level != handle->max_depth)) 532 goto retry; 533 534 if ((orig_op == EXT2_EXTENT_LAST_LEAF) && 535 ((handle->level != handle->max_depth) || 536 (path->left != 0))) 537 goto retry; 538 539 return 0; 540} 541 542static errcode_t update_path(ext2_extent_handle_t handle) 543{ 544 blk64_t blk; 545 errcode_t retval; 546 struct ext3_extent_idx *ix; 547 548 if (handle->level == 0) { 549 retval = ext2fs_write_inode(handle->fs, handle->ino, 550 handle->inode); 551 } else { 552 ix = handle->path[handle->level - 1].curr; 553 blk = ext2fs_le32_to_cpu(ix->ei_leaf) + 554 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32); 555 556 retval = io_channel_write_blk64(handle->fs->io, 557 blk, 1, handle->path[handle->level].buf); 558 } 559 return retval; 560} 561 562#if 0 563errcode_t ext2fs_extent_save_path(ext2_extent_handle_t handle, 564 ext2_extent_path_t *ret_path) 565{ 566 ext2_extent_path_t save_path; 567 struct ext2fs_extent extent; 568 struct ext2_extent_info info; 569 errcode_t retval; 570 571 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent); 572 if (retval) 573 return retval; 574 575 retval = ext2fs_extent_get_info(handle, &info); 576 if (retval) 577 return retval; 578 579 retval = ext2fs_get_mem(sizeof(struct ext2_extent_path), &save_path); 580 if (retval) 581 return retval; 582 memset(save_path, 0, sizeof(struct ext2_extent_path)); 583 584 save_path->magic = EXT2_ET_MAGIC_EXTENT_PATH; 585 save_path->leaf_height = info.max_depth - info.curr_level - 1; 586 save_path->lblk = extent.e_lblk; 587 588 *ret_path = save_path; 589 return 0; 590} 591 592errcode_t ext2fs_extent_free_path(ext2_extent_path_t path) 593{ 594 EXT2_CHECK_MAGIC(path, EXT2_ET_MAGIC_EXTENT_PATH); 595 596 ext2fs_free_mem(&path); 597 return 0; 598} 599#endif 600 601/* 602 * Go to the node at leaf_level which contains logical block blk. 603 * 604 * leaf_level is height from the leaf node level, i.e. 605 * leaf_level 0 is at leaf node, leaf_level 1 is 1 above etc. 606 * 607 * If "blk" has no mapping (hole) then handle is left at last 608 * extent before blk. 609 */ 610static errcode_t extent_goto(ext2_extent_handle_t handle, 611 int leaf_level, blk64_t blk) 612{ 613 struct ext2fs_extent extent; 614 errcode_t retval; 615 616 retval = ext2fs_extent_get(handle, EXT2_EXTENT_ROOT, &extent); 617 if (retval) { 618 if (retval == EXT2_ET_EXTENT_NO_NEXT) 619 retval = EXT2_ET_EXTENT_NOT_FOUND; 620 return retval; 621 } 622 623 if (leaf_level > handle->max_depth) { 624#ifdef DEBUG 625 printf("leaf level %d greater than tree depth %d\n", 626 leaf_level, handle->max_depth); 627#endif 628 return EXT2_ET_OP_NOT_SUPPORTED; 629 } 630 631#ifdef DEBUG 632 printf("goto extent ino %u, level %d, %llu\n", handle->ino, 633 leaf_level, blk); 634#endif 635 636#ifdef DEBUG_GOTO_EXTENTS 637 dbg_print_extent("root", &extent); 638#endif 639 while (1) { 640 if (handle->max_depth - handle->level == leaf_level) { 641 /* block is in this &extent */ 642 if ((blk >= extent.e_lblk) && 643 (blk < extent.e_lblk + extent.e_len)) 644 return 0; 645 if (blk < extent.e_lblk) { 646 retval = ext2fs_extent_get(handle, 647 EXT2_EXTENT_PREV_SIB, 648 &extent); 649 return EXT2_ET_EXTENT_NOT_FOUND; 650 } 651 retval = ext2fs_extent_get(handle, 652 EXT2_EXTENT_NEXT_SIB, 653 &extent); 654 if (retval == EXT2_ET_EXTENT_NO_NEXT) 655 return EXT2_ET_EXTENT_NOT_FOUND; 656 if (retval) 657 return retval; 658 continue; 659 } 660 661 retval = ext2fs_extent_get(handle, EXT2_EXTENT_NEXT_SIB, 662 &extent); 663 if (retval == EXT2_ET_EXTENT_NO_NEXT) 664 goto go_down; 665 if (retval) 666 return retval; 667 668#ifdef DEBUG_GOTO_EXTENTS 669 dbg_print_extent("next", &extent); 670#endif 671 if (blk == extent.e_lblk) 672 goto go_down; 673 if (blk > extent.e_lblk) 674 continue; 675 676 retval = ext2fs_extent_get(handle, EXT2_EXTENT_PREV_SIB, 677 &extent); 678 if (retval) 679 return retval; 680 681#ifdef DEBUG_GOTO_EXTENTS 682 dbg_print_extent("prev", &extent); 683#endif 684 685 go_down: 686 retval = ext2fs_extent_get(handle, EXT2_EXTENT_DOWN, 687 &extent); 688 if (retval) 689 return retval; 690 691#ifdef DEBUG_GOTO_EXTENTS 692 dbg_print_extent("down", &extent); 693#endif 694 } 695} 696 697errcode_t ext2fs_extent_goto(ext2_extent_handle_t handle, 698 blk64_t blk) 699{ 700 return extent_goto(handle, 0, blk); 701} 702 703/* 704 * Traverse back up to root fixing parents of current node as needed. 705 * 706 * If we changed start of first entry in a node, fix parent index start 707 * and so on. 708 * 709 * Safe to call for any position in node; if not at the first entry, 710 * will simply return. 711 */ 712static errcode_t ext2fs_extent_fix_parents(ext2_extent_handle_t handle) 713{ 714 int retval = 0; 715 blk64_t start; 716 struct extent_path *path; 717 struct ext2fs_extent extent; 718 719 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 720 721 if (!(handle->fs->flags & EXT2_FLAG_RW)) 722 return EXT2_ET_RO_FILSYS; 723 724 if (!handle->path) 725 return EXT2_ET_NO_CURRENT_NODE; 726 727 path = handle->path + handle->level; 728 if (!path->curr) 729 return EXT2_ET_NO_CURRENT_NODE; 730 731 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent); 732 if (retval) 733 goto done; 734 735 /* modified node's start block */ 736 start = extent.e_lblk; 737 738 /* traverse up until index not first, or startblk matches, or top */ 739 while (handle->level > 0 && 740 (path->left == path->entries - 1)) { 741 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP, &extent); 742 if (retval) 743 goto done; 744 if (extent.e_lblk == start) 745 break; 746 path = handle->path + handle->level; 747 extent.e_len += (extent.e_lblk - start); 748 extent.e_lblk = start; 749 retval = ext2fs_extent_replace(handle, 0, &extent); 750 if (retval) 751 goto done; 752 update_path(handle); 753 } 754 755 /* put handle back to where we started */ 756 retval = ext2fs_extent_goto(handle, start); 757done: 758 return retval; 759} 760 761errcode_t ext2fs_extent_replace(ext2_extent_handle_t handle, 762 int flags EXT2FS_ATTR((unused)), 763 struct ext2fs_extent *extent) 764{ 765 struct extent_path *path; 766 struct ext3_extent_idx *ix; 767 struct ext3_extent *ex; 768 769 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 770 771 if (!(handle->fs->flags & EXT2_FLAG_RW)) 772 return EXT2_ET_RO_FILSYS; 773 774 if (!handle->path) 775 return EXT2_ET_NO_CURRENT_NODE; 776 777 path = handle->path + handle->level; 778 if (!path->curr) 779 return EXT2_ET_NO_CURRENT_NODE; 780 781#ifdef DEBUG 782 printf("extent replace: %u ", handle->ino); 783 dbg_print_extent(0, extent); 784#endif 785 786 if (handle->level == handle->max_depth) { 787 ex = path->curr; 788 789 ex->ee_block = ext2fs_cpu_to_le32(extent->e_lblk); 790 ex->ee_start = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF); 791 ex->ee_start_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32); 792 if (extent->e_flags & EXT2_EXTENT_FLAGS_UNINIT) { 793 if (extent->e_len > EXT_UNINIT_MAX_LEN) 794 return EXT2_ET_EXTENT_INVALID_LENGTH; 795 ex->ee_len = ext2fs_cpu_to_le16(extent->e_len + 796 EXT_INIT_MAX_LEN); 797 } else { 798 if (extent->e_len > EXT_INIT_MAX_LEN) 799 return EXT2_ET_EXTENT_INVALID_LENGTH; 800 ex->ee_len = ext2fs_cpu_to_le16(extent->e_len); 801 } 802 } else { 803 ix = path->curr; 804 805 ix->ei_leaf = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF); 806 ix->ei_leaf_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32); 807 ix->ei_block = ext2fs_cpu_to_le32(extent->e_lblk); 808 ix->ei_unused = 0; 809 } 810 update_path(handle); 811 return 0; 812} 813 814/* 815 * allocate a new block, move half the current node to it, and update parent 816 * 817 * handle will be left pointing at original record. 818 */ 819static errcode_t extent_node_split(ext2_extent_handle_t handle) 820{ 821 errcode_t retval = 0; 822 blk64_t new_node_pblk; 823 blk64_t new_node_start; 824 blk64_t orig_lblk; 825 blk64_t goal_blk = 0; 826 int orig_height; 827 char *block_buf = NULL; 828 struct ext2fs_extent extent; 829 struct extent_path *path, *newpath = 0; 830 struct ext3_extent_header *eh, *neweh; 831 int tocopy; 832 int new_root = 0; 833 struct ext2_extent_info info; 834 835 /* basic sanity */ 836 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 837 838 if (!(handle->fs->flags & EXT2_FLAG_RW)) 839 return EXT2_ET_RO_FILSYS; 840 841 if (!handle->path) 842 return EXT2_ET_NO_CURRENT_NODE; 843 844#ifdef DEBUG 845 printf("splitting node at level %d\n", handle->level); 846#endif 847 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent); 848 if (retval) 849 goto done; 850 851 retval = ext2fs_extent_get_info(handle, &info); 852 if (retval) 853 goto done; 854 855 /* save the position we were originally splitting... */ 856 orig_height = info.max_depth - info.curr_level; 857 orig_lblk = extent.e_lblk; 858 859 /* Is there room in the parent for a new entry? */ 860 if (handle->level && 861 (handle->path[handle->level - 1].entries >= 862 handle->path[handle->level - 1].max_entries)) { 863 864#ifdef DEBUG 865 printf("parent level %d full; splitting it too\n", 866 handle->level - 1); 867#endif 868 /* split the parent */ 869 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP, &extent); 870 if (retval) 871 goto done; 872 goal_blk = extent.e_pblk; 873 874 retval = extent_node_split(handle); 875 if (retval) 876 goto done; 877 878 /* get handle back to our original split position */ 879 retval = extent_goto(handle, orig_height, orig_lblk); 880 if (retval) 881 goto done; 882 } 883 884 /* At this point, parent should have room for this split */ 885 path = handle->path + handle->level; 886 if (!path->curr) 887 return EXT2_ET_NO_CURRENT_NODE; 888 889 /* extent header of the current node we'll split */ 890 eh = (struct ext3_extent_header *)path->buf; 891 892 /* splitting root level means moving them all out */ 893 if (handle->level == 0) { 894 new_root = 1; 895 tocopy = ext2fs_le16_to_cpu(eh->eh_entries); 896 retval = ext2fs_get_mem(((handle->max_depth+2) * 897 sizeof(struct extent_path)), 898 &newpath); 899 if (retval) 900 goto done; 901 memset(newpath, 0, 902 ((handle->max_depth+2) * sizeof(struct extent_path))); 903 } else { 904 tocopy = ext2fs_le16_to_cpu(eh->eh_entries) / 2; 905 } 906 907#ifdef DEBUG 908 printf("will copy out %d of %d entries at level %d\n", 909 tocopy, ext2fs_le16_to_cpu(eh->eh_entries), 910 handle->level); 911#endif 912 913 if (!tocopy) { 914#ifdef DEBUG 915 printf("Nothing to copy to new block!\n"); 916#endif 917 retval = EXT2_ET_CANT_SPLIT_EXTENT; 918 goto done; 919 } 920 921 /* first we need a new block, or can do nothing. */ 922 block_buf = malloc(handle->fs->blocksize); 923 if (!block_buf) { 924 retval = ENOMEM; 925 goto done; 926 } 927 928 if (!goal_blk) { 929 dgrp_t group = ext2fs_group_of_ino(handle->fs, handle->ino); 930 __u8 log_flex = handle->fs->super->s_log_groups_per_flex; 931 932 if (log_flex) 933 group = group & ~((1 << (log_flex)) - 1); 934 goal_blk = (group * handle->fs->super->s_blocks_per_group) + 935 handle->fs->super->s_first_data_block; 936 } 937 retval = ext2fs_alloc_block2(handle->fs, goal_blk, block_buf, 938 &new_node_pblk); 939 if (retval) 940 goto done; 941 942#ifdef DEBUG 943 printf("will copy to new node at block %lu\n", 944 (unsigned long) new_node_pblk); 945#endif 946 947 /* Copy data into new block buffer */ 948 /* First the header for the new block... */ 949 neweh = (struct ext3_extent_header *) block_buf; 950 memcpy(neweh, eh, sizeof(struct ext3_extent_header)); 951 neweh->eh_entries = ext2fs_cpu_to_le16(tocopy); 952 neweh->eh_max = ext2fs_cpu_to_le16((handle->fs->blocksize - 953 sizeof(struct ext3_extent_header)) / 954 sizeof(struct ext3_extent)); 955 956 /* then the entries for the new block... */ 957 memcpy(EXT_FIRST_INDEX(neweh), 958 EXT_FIRST_INDEX(eh) + 959 (ext2fs_le16_to_cpu(eh->eh_entries) - tocopy), 960 sizeof(struct ext3_extent_idx) * tocopy); 961 962 new_node_start = ext2fs_le32_to_cpu(EXT_FIRST_INDEX(neweh)->ei_block); 963 964 /* ...and write the new node block out to disk. */ 965 retval = io_channel_write_blk64(handle->fs->io, new_node_pblk, 1, 966 block_buf); 967 968 if (retval) 969 goto done; 970 971 /* OK! we've created the new node; now adjust the tree */ 972 973 /* current path now has fewer active entries, we copied some out */ 974 if (handle->level == 0) { 975 memcpy(newpath, path, 976 sizeof(struct extent_path) * (handle->max_depth+1)); 977 handle->path = newpath; 978 newpath = path; 979 path = handle->path; 980 path->entries = 1; 981 path->left = path->max_entries - 1; 982 handle->max_depth++; 983 eh->eh_depth = ext2fs_cpu_to_le16(handle->max_depth); 984 } else { 985 path->entries -= tocopy; 986 path->left -= tocopy; 987 } 988 989 eh->eh_entries = ext2fs_cpu_to_le16(path->entries); 990 /* this writes out the node, incl. the modified header */ 991 retval = update_path(handle); 992 if (retval) 993 goto done; 994 995 /* now go up and insert/replace index for new node we created */ 996 if (new_root) { 997 retval = ext2fs_extent_get(handle, EXT2_EXTENT_FIRST_SIB, &extent); 998 if (retval) 999 goto done; 1000 1001 extent.e_lblk = new_node_start; 1002 extent.e_pblk = new_node_pblk; 1003 extent.e_len = handle->path[0].end_blk - extent.e_lblk; 1004 retval = ext2fs_extent_replace(handle, 0, &extent); 1005 if (retval) 1006 goto done; 1007 } else { 1008 __u32 new_node_length; 1009 1010 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP, &extent); 1011 /* will insert after this one; it's length is shorter now */ 1012 new_node_length = new_node_start - extent.e_lblk; 1013 extent.e_len -= new_node_length; 1014 retval = ext2fs_extent_replace(handle, 0, &extent); 1015 if (retval) 1016 goto done; 1017 1018 /* now set up the new extent and insert it */ 1019 extent.e_lblk = new_node_start; 1020 extent.e_pblk = new_node_pblk; 1021 extent.e_len = new_node_length; 1022 retval = ext2fs_extent_insert(handle, EXT2_EXTENT_INSERT_AFTER, &extent); 1023 if (retval) 1024 goto done; 1025 } 1026 1027 /* get handle back to our original position */ 1028 retval = extent_goto(handle, orig_height, orig_lblk); 1029 if (retval) 1030 goto done; 1031 1032 /* new node hooked in, so update inode block count (do this here?) */ 1033 handle->inode->i_blocks += handle->fs->blocksize / 512; 1034 retval = ext2fs_write_inode(handle->fs, handle->ino, 1035 handle->inode); 1036 if (retval) 1037 goto done; 1038 1039done: 1040 if (newpath) 1041 ext2fs_free_mem(&newpath); 1042 free(block_buf); 1043 1044 return retval; 1045} 1046 1047errcode_t ext2fs_extent_insert(ext2_extent_handle_t handle, int flags, 1048 struct ext2fs_extent *extent) 1049{ 1050 struct extent_path *path; 1051 struct ext3_extent_idx *ix; 1052 struct ext3_extent_header *eh; 1053 errcode_t retval; 1054 1055 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 1056 1057 if (!(handle->fs->flags & EXT2_FLAG_RW)) 1058 return EXT2_ET_RO_FILSYS; 1059 1060 if (!handle->path) 1061 return EXT2_ET_NO_CURRENT_NODE; 1062 1063#ifdef DEBUG 1064 printf("extent insert: %u ", handle->ino); 1065 dbg_print_extent(0, extent); 1066#endif 1067 1068 path = handle->path + handle->level; 1069 1070 if (path->entries >= path->max_entries) { 1071 if (flags & EXT2_EXTENT_INSERT_NOSPLIT) { 1072 return EXT2_ET_CANT_INSERT_EXTENT; 1073 } else { 1074#ifdef DEBUG 1075 printf("node full (level %d) - splitting\n", 1076 handle->level); 1077#endif 1078 retval = extent_node_split(handle); 1079 if (retval) 1080 return retval; 1081 path = handle->path + handle->level; 1082 } 1083 } 1084 1085 eh = (struct ext3_extent_header *) path->buf; 1086 if (path->curr) { 1087 ix = path->curr; 1088 if (flags & EXT2_EXTENT_INSERT_AFTER) { 1089 ix++; 1090 path->left--; 1091 } 1092 } else 1093 ix = EXT_FIRST_INDEX(eh); 1094 1095 path->curr = ix; 1096 1097 if (path->left >= 0) 1098 memmove(ix + 1, ix, 1099 (path->left+1) * sizeof(struct ext3_extent_idx)); 1100 path->left++; 1101 path->entries++; 1102 1103 eh = (struct ext3_extent_header *) path->buf; 1104 eh->eh_entries = ext2fs_cpu_to_le16(path->entries); 1105 1106 retval = ext2fs_extent_replace(handle, 0, extent); 1107 if (retval) 1108 goto errout; 1109 1110 retval = update_path(handle); 1111 if (retval) 1112 goto errout; 1113 1114 return 0; 1115 1116errout: 1117 ext2fs_extent_delete(handle, 0); 1118 return retval; 1119} 1120 1121/* 1122 * Sets the physical block for a logical file block in the extent tree. 1123 * 1124 * May: map unmapped, unmap mapped, or remap mapped blocks. 1125 * 1126 * Mapping an unmapped block adds a single-block extent. 1127 * 1128 * Unmapping first or last block modifies extent in-place 1129 * - But may need to fix parent's starts too in first-block case 1130 * 1131 * Mapping any unmapped block requires adding a (single-block) extent 1132 * and inserting into proper point in tree. 1133 * 1134 * Modifying (unmapping or remapping) a block in the middle 1135 * of an extent requires splitting the extent. 1136 * - Remapping case requires new single-block extent. 1137 * 1138 * Remapping first or last block adds an extent. 1139 * 1140 * We really need extent adding to be smart about merging. 1141 */ 1142 1143errcode_t ext2fs_extent_set_bmap(ext2_extent_handle_t handle, 1144 blk64_t logical, blk64_t physical, int flags) 1145{ 1146 errcode_t ec, retval = 0; 1147 int mapped = 1; /* logical is mapped? */ 1148 int orig_height; 1149 int extent_uninit = 0; 1150 int prev_uninit = 0; 1151 int next_uninit = 0; 1152 int new_uninit = 0; 1153 int max_len = EXT_INIT_MAX_LEN; 1154 int has_prev, has_next; 1155 blk64_t orig_lblk; 1156 struct extent_path *path; 1157 struct ext2fs_extent extent, next_extent, prev_extent; 1158 struct ext2fs_extent newextent; 1159 struct ext2_extent_info info; 1160 1161 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 1162 1163#ifdef DEBUG 1164 printf("set_bmap ino %u log %lld phys %lld flags %d\n", 1165 handle->ino, logical, physical, flags); 1166#endif 1167 1168 if (!(handle->fs->flags & EXT2_FLAG_RW)) 1169 return EXT2_ET_RO_FILSYS; 1170 1171 if (!handle->path) 1172 return EXT2_ET_NO_CURRENT_NODE; 1173 1174 path = handle->path + handle->level; 1175 1176 if (flags & EXT2_EXTENT_SET_BMAP_UNINIT) { 1177 new_uninit = 1; 1178 max_len = EXT_UNINIT_MAX_LEN; 1179 } 1180 1181 /* if (re)mapping, set up new extent to insert */ 1182 if (physical) { 1183 newextent.e_len = 1; 1184 newextent.e_pblk = physical; 1185 newextent.e_lblk = logical; 1186 newextent.e_flags = EXT2_EXTENT_FLAGS_LEAF; 1187 if (new_uninit) 1188 newextent.e_flags |= EXT2_EXTENT_FLAGS_UNINIT; 1189 } 1190 1191 /* special case if the extent tree is completely empty */ 1192 if ((handle->max_depth == 0) && (path->entries == 0)) { 1193 retval = ext2fs_extent_insert(handle, 0, &newextent); 1194 return retval; 1195 } 1196 1197 /* save our original location in the extent tree */ 1198 if ((retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, 1199 &extent))) { 1200 if (retval != EXT2_ET_NO_CURRENT_NODE) 1201 return retval; 1202 memset(&extent, 0, sizeof(extent)); 1203 } 1204 if ((retval = ext2fs_extent_get_info(handle, &info))) 1205 return retval; 1206 orig_height = info.max_depth - info.curr_level; 1207 orig_lblk = extent.e_lblk; 1208 1209 /* go to the logical spot we want to (re/un)map */ 1210 retval = ext2fs_extent_goto(handle, logical); 1211 if (retval) { 1212 if (retval == EXT2_ET_EXTENT_NOT_FOUND) { 1213 retval = 0; 1214 mapped = 0; 1215 if (!physical) { 1216#ifdef DEBUG 1217 printf("block %llu already unmapped\n", 1218 logical); 1219#endif 1220 goto done; 1221 } 1222 } else 1223 goto done; 1224 } 1225 1226 /* 1227 * This may be the extent *before* the requested logical, 1228 * if it's currently unmapped. 1229 * 1230 * Get the previous and next leaf extents, if they are present. 1231 */ 1232 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent); 1233 if (retval) 1234 goto done; 1235 if (extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT) 1236 extent_uninit = 1; 1237 retval = ext2fs_extent_get(handle, EXT2_EXTENT_NEXT_LEAF, &next_extent); 1238 if (retval) { 1239 has_next = 0; 1240 if (retval != EXT2_ET_EXTENT_NO_NEXT) 1241 goto done; 1242 } else { 1243 dbg_print_extent("set_bmap: next_extent", 1244 &next_extent); 1245 has_next = 1; 1246 if (next_extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT) 1247 next_uninit = 1; 1248 } 1249 retval = ext2fs_extent_goto(handle, logical); 1250 if (retval && retval != EXT2_ET_EXTENT_NOT_FOUND) 1251 goto done; 1252 retval = ext2fs_extent_get(handle, EXT2_EXTENT_PREV_LEAF, &prev_extent); 1253 if (retval) { 1254 has_prev = 0; 1255 if (retval != EXT2_ET_EXTENT_NO_PREV) 1256 goto done; 1257 } else { 1258 has_prev = 1; 1259 dbg_print_extent("set_bmap: prev_extent", 1260 &prev_extent); 1261 if (prev_extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT) 1262 prev_uninit = 1; 1263 } 1264 retval = ext2fs_extent_goto(handle, logical); 1265 if (retval && retval != EXT2_ET_EXTENT_NOT_FOUND) 1266 goto done; 1267 1268 /* check if already pointing to the requested physical */ 1269 if (mapped && (new_uninit == extent_uninit) && 1270 (extent.e_pblk + (logical - extent.e_lblk) == physical)) { 1271#ifdef DEBUG 1272 printf("physical block (at %llu) unchanged\n", logical); 1273#endif 1274 goto done; 1275 } 1276 1277 if (!mapped) { 1278#ifdef DEBUG 1279 printf("mapping unmapped logical block %llu\n", logical); 1280#endif 1281 if ((logical == extent.e_lblk + extent.e_len) && 1282 (physical == extent.e_pblk + extent.e_len) && 1283 (new_uninit == extent_uninit) && 1284 ((int) extent.e_len < max_len-1)) { 1285 extent.e_len++; 1286 retval = ext2fs_extent_replace(handle, 0, &extent); 1287 } else if ((logical == extent.e_lblk - 1) && 1288 (physical == extent.e_pblk - 1) && 1289 (new_uninit == extent_uninit) && 1290 ((int) extent.e_len < max_len - 1)) { 1291 extent.e_len++; 1292 extent.e_lblk--; 1293 extent.e_pblk--; 1294 retval = ext2fs_extent_replace(handle, 0, &extent); 1295 } else if (has_next && 1296 (logical == next_extent.e_lblk - 1) && 1297 (physical == next_extent.e_pblk - 1) && 1298 (new_uninit == next_uninit) && 1299 ((int) next_extent.e_len < max_len - 1)) { 1300 retval = ext2fs_extent_get(handle, 1301 EXT2_EXTENT_NEXT_LEAF, 1302 &next_extent); 1303 if (retval) 1304 goto done; 1305 next_extent.e_len++; 1306 next_extent.e_lblk--; 1307 next_extent.e_pblk--; 1308 retval = ext2fs_extent_replace(handle, 0, &next_extent); 1309 } else if (logical < extent.e_lblk) 1310 retval = ext2fs_extent_insert(handle, 0, &newextent); 1311 else 1312 retval = ext2fs_extent_insert(handle, 1313 EXT2_EXTENT_INSERT_AFTER, &newextent); 1314 if (retval) 1315 goto done; 1316 retval = ext2fs_extent_fix_parents(handle); 1317 if (retval) 1318 goto done; 1319 } else if ((logical == extent.e_lblk) && (extent.e_len == 1)) { 1320#ifdef DEBUG 1321 printf("(re/un)mapping only block in extent\n"); 1322#endif 1323 if (physical) { 1324 retval = ext2fs_extent_replace(handle, 0, &newextent); 1325 } else { 1326 retval = ext2fs_extent_delete(handle, 0); 1327 if (retval) 1328 goto done; 1329 ec = ext2fs_extent_fix_parents(handle); 1330 if (ec != EXT2_ET_NO_CURRENT_NODE) 1331 retval = ec; 1332 } 1333 1334 if (retval) 1335 goto done; 1336 } else if (logical == extent.e_lblk + extent.e_len - 1) { 1337#ifdef DEBUG 1338 printf("(re/un)mapping last block in extent\n"); 1339#endif 1340 if (physical) { 1341 if (has_next && 1342 (logical == (next_extent.e_lblk - 1)) && 1343 (physical == (next_extent.e_pblk - 1)) && 1344 (new_uninit == next_uninit) && 1345 ((int) next_extent.e_len < max_len - 1)) { 1346 retval = ext2fs_extent_get(handle, 1347 EXT2_EXTENT_NEXT_LEAF, &next_extent); 1348 if (retval) 1349 goto done; 1350 next_extent.e_len++; 1351 next_extent.e_lblk--; 1352 next_extent.e_pblk--; 1353 retval = ext2fs_extent_replace(handle, 0, 1354 &next_extent); 1355 if (retval) 1356 goto done; 1357 } else 1358 retval = ext2fs_extent_insert(handle, 1359 EXT2_EXTENT_INSERT_AFTER, &newextent); 1360 if (retval) 1361 goto done; 1362 /* Now pointing at inserted extent; move back to prev */ 1363 retval = ext2fs_extent_get(handle, 1364 EXT2_EXTENT_PREV_LEAF, 1365 &extent); 1366 if (retval) 1367 goto done; 1368 } 1369 extent.e_len--; 1370 retval = ext2fs_extent_replace(handle, 0, &extent); 1371 if (retval) 1372 goto done; 1373 } else if (logical == extent.e_lblk) { 1374#ifdef DEBUG 1375 printf("(re/un)mapping first block in extent\n"); 1376#endif 1377 if (physical) { 1378 if (has_prev && 1379 (logical == (prev_extent.e_lblk + 1380 prev_extent.e_len)) && 1381 (physical == (prev_extent.e_pblk + 1382 prev_extent.e_len)) && 1383 (new_uninit == prev_uninit) && 1384 ((int) prev_extent.e_len < max_len-1)) { 1385 retval = ext2fs_extent_get(handle, 1386 EXT2_EXTENT_PREV_LEAF, &prev_extent); 1387 if (retval) 1388 goto done; 1389 prev_extent.e_len++; 1390 retval = ext2fs_extent_replace(handle, 0, 1391 &prev_extent); 1392 } else 1393 retval = ext2fs_extent_insert(handle, 1394 0, &newextent); 1395 if (retval) 1396 goto done; 1397 retval = ext2fs_extent_get(handle, 1398 EXT2_EXTENT_NEXT_LEAF, 1399 &extent); 1400 if (retval) 1401 goto done; 1402 } 1403 extent.e_pblk++; 1404 extent.e_lblk++; 1405 extent.e_len--; 1406 retval = ext2fs_extent_replace(handle, 0, &extent); 1407 if (retval) 1408 goto done; 1409 } else { 1410 __u32 orig_length; 1411 1412#ifdef DEBUG 1413 printf("(re/un)mapping in middle of extent\n"); 1414#endif 1415 /* need to split this extent; later */ 1416 1417 orig_length = extent.e_len; 1418 1419 /* shorten pre-split extent */ 1420 extent.e_len = (logical - extent.e_lblk); 1421 retval = ext2fs_extent_replace(handle, 0, &extent); 1422 if (retval) 1423 goto done; 1424 /* insert our new extent, if any */ 1425 if (physical) { 1426 /* insert new extent after current */ 1427 retval = ext2fs_extent_insert(handle, 1428 EXT2_EXTENT_INSERT_AFTER, &newextent); 1429 if (retval) 1430 goto done; 1431 } 1432 /* add post-split extent */ 1433 extent.e_pblk += extent.e_len + 1; 1434 extent.e_lblk += extent.e_len + 1; 1435 extent.e_len = orig_length - extent.e_len - 1; 1436 retval = ext2fs_extent_insert(handle, 1437 EXT2_EXTENT_INSERT_AFTER, &extent); 1438 if (retval) 1439 goto done; 1440 } 1441 1442done: 1443 /* get handle back to its position */ 1444 if (orig_height > handle->max_depth) 1445 orig_height = handle->max_depth; /* In case we shortened the tree */ 1446 extent_goto(handle, orig_height, orig_lblk); 1447 return retval; 1448} 1449 1450errcode_t ext2fs_extent_delete(ext2_extent_handle_t handle, int flags) 1451{ 1452 struct extent_path *path; 1453 char *cp; 1454 struct ext3_extent_header *eh; 1455 errcode_t retval = 0; 1456 1457 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 1458 1459 if (!(handle->fs->flags & EXT2_FLAG_RW)) 1460 return EXT2_ET_RO_FILSYS; 1461 1462 if (!handle->path) 1463 return EXT2_ET_NO_CURRENT_NODE; 1464 1465#ifdef DEBUG 1466 { 1467 struct ext2fs_extent extent; 1468 1469 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, 1470 &extent); 1471 if (retval == 0) { 1472 printf("extent delete %u ", handle->ino); 1473 dbg_print_extent(0, &extent); 1474 } 1475 } 1476#endif 1477 1478 path = handle->path + handle->level; 1479 if (!path->curr) 1480 return EXT2_ET_NO_CURRENT_NODE; 1481 1482 cp = path->curr; 1483 1484 if (path->left) { 1485 memmove(cp, cp + sizeof(struct ext3_extent_idx), 1486 path->left * sizeof(struct ext3_extent_idx)); 1487 path->left--; 1488 } else { 1489 struct ext3_extent_idx *ix = path->curr; 1490 ix--; 1491 path->curr = ix; 1492 } 1493 if (--path->entries == 0) 1494 path->curr = 0; 1495 1496 /* if non-root node has no entries left, remove it & parent ptr to it */ 1497 if (path->entries == 0 && handle->level) { 1498 if (!(flags & EXT2_EXTENT_DELETE_KEEP_EMPTY)) { 1499 struct ext2fs_extent extent; 1500 1501 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP, 1502 &extent); 1503 if (retval) 1504 return retval; 1505 1506 retval = ext2fs_extent_delete(handle, flags); 1507 handle->inode->i_blocks -= handle->fs->blocksize / 512; 1508 retval = ext2fs_write_inode(handle->fs, handle->ino, 1509 handle->inode); 1510 ext2fs_block_alloc_stats2(handle->fs, 1511 extent.e_pblk, -1); 1512 } 1513 } else { 1514 eh = (struct ext3_extent_header *) path->buf; 1515 eh->eh_entries = ext2fs_cpu_to_le16(path->entries); 1516 if ((path->entries == 0) && (handle->level == 0)) 1517 eh->eh_depth = handle->max_depth = 0; 1518 retval = update_path(handle); 1519 } 1520 return retval; 1521} 1522 1523errcode_t ext2fs_extent_get_info(ext2_extent_handle_t handle, 1524 struct ext2_extent_info *info) 1525{ 1526 struct extent_path *path; 1527 1528 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 1529 1530 memset(info, 0, sizeof(struct ext2_extent_info)); 1531 1532 path = handle->path + handle->level; 1533 if (path) { 1534 if (path->curr) 1535 info->curr_entry = ((char *) path->curr - path->buf) / 1536 sizeof(struct ext3_extent_idx); 1537 else 1538 info->curr_entry = 0; 1539 info->num_entries = path->entries; 1540 info->max_entries = path->max_entries; 1541 info->bytes_avail = (path->max_entries - path->entries) * 1542 sizeof(struct ext3_extent); 1543 } 1544 1545 info->curr_level = handle->level; 1546 info->max_depth = handle->max_depth; 1547 info->max_lblk = ((__u64) 1 << 32) - 1; 1548 info->max_pblk = ((__u64) 1 << 48) - 1; 1549 info->max_len = (1UL << 15); 1550 info->max_uninit_len = (1UL << 15) - 1; 1551 1552 return 0; 1553} 1554 1555#ifdef DEBUG 1556 1557#include "ss/ss.h" 1558 1559#include "debugfs.h" 1560 1561/* 1562 * Hook in new commands into debugfs 1563 */ 1564const char *debug_prog_name = "tst_extents"; 1565extern ss_request_table extent_cmds; 1566ss_request_table *extra_cmds = &extent_cmds; 1567 1568ext2_ino_t current_ino = 0; 1569ext2_extent_handle_t current_handle; 1570 1571int common_extent_args_process(int argc, char *argv[], int min_argc, 1572 int max_argc, const char *cmd, 1573 const char *usage, int flags) 1574{ 1575 if (common_args_process(argc, argv, min_argc, max_argc, cmd, 1576 usage, flags)) 1577 return 1; 1578 1579 if (!current_handle) { 1580 com_err(cmd, 0, "Extent handle not open"); 1581 return 1; 1582 } 1583 return 0; 1584} 1585 1586void do_inode(int argc, char *argv[]) 1587{ 1588 ext2_ino_t inode; 1589 int i; 1590 struct ext3_extent_header *eh; 1591 errcode_t retval; 1592 1593 if (check_fs_open(argv[0])) 1594 return; 1595 1596 if (argc == 1) { 1597 if (current_ino) 1598 printf("Current inode is %d\n", current_ino); 1599 else 1600 printf("No current inode\n"); 1601 return; 1602 } 1603 1604 if (common_inode_args_process(argc, argv, &inode, 0)) { 1605 return; 1606 } 1607 1608 current_ino = 0; 1609 1610 retval = ext2fs_extent_open(current_fs, inode, ¤t_handle); 1611 if (retval) { 1612 com_err(argv[1], retval, "while opening extent handle"); 1613 return; 1614 } 1615 1616 current_ino = inode; 1617 1618 printf("Loaded inode %d\n", current_ino); 1619 1620 return; 1621} 1622 1623void generic_goto_node(char *cmd_name, int op) 1624{ 1625 struct ext2fs_extent extent; 1626 errcode_t retval; 1627 1628 if (check_fs_open(cmd_name)) 1629 return; 1630 1631 if (!current_handle) { 1632 com_err(cmd_name, 0, "Extent handle not open"); 1633 return; 1634 } 1635 1636 retval = ext2fs_extent_get(current_handle, op, &extent); 1637 if (retval) { 1638 com_err(cmd_name, retval, 0); 1639 return; 1640 } 1641 dbg_print_extent(0, &extent); 1642} 1643 1644void do_current_node(int argc, char *argv[]) 1645{ 1646 generic_goto_node(argv[0], EXT2_EXTENT_CURRENT); 1647} 1648 1649void do_root_node(int argc, char *argv[]) 1650{ 1651 generic_goto_node(argv[0], EXT2_EXTENT_ROOT); 1652} 1653 1654void do_last_leaf(int argc, char *argv[]) 1655{ 1656 generic_goto_node(argv[0], EXT2_EXTENT_LAST_LEAF); 1657} 1658 1659void do_first_sib(int argc, char *argv[]) 1660{ 1661 generic_goto_node(argv[0], EXT2_EXTENT_FIRST_SIB); 1662} 1663 1664void do_last_sib(int argc, char *argv[]) 1665{ 1666 generic_goto_node(argv[0], EXT2_EXTENT_LAST_SIB); 1667} 1668 1669void do_next_sib(int argc, char *argv[]) 1670{ 1671 generic_goto_node(argv[0], EXT2_EXTENT_NEXT_SIB); 1672} 1673 1674void do_prev_sib(int argc, char *argv[]) 1675{ 1676 generic_goto_node(argv[0], EXT2_EXTENT_PREV_SIB); 1677} 1678 1679void do_next_leaf(int argc, char *argv[]) 1680{ 1681 generic_goto_node(argv[0], EXT2_EXTENT_NEXT_LEAF); 1682} 1683 1684void do_prev_leaf(int argc, char *argv[]) 1685{ 1686 generic_goto_node(argv[0], EXT2_EXTENT_PREV_LEAF); 1687} 1688 1689void do_next(int argc, char *argv[]) 1690{ 1691 generic_goto_node(argv[0], EXT2_EXTENT_NEXT); 1692} 1693 1694void do_prev(int argc, char *argv[]) 1695{ 1696 generic_goto_node(argv[0], EXT2_EXTENT_PREV); 1697} 1698 1699void do_up(int argc, char *argv[]) 1700{ 1701 generic_goto_node(argv[0], EXT2_EXTENT_UP); 1702} 1703 1704void do_down(int argc, char *argv[]) 1705{ 1706 generic_goto_node(argv[0], EXT2_EXTENT_DOWN); 1707} 1708 1709void do_delete_node(int argc, char *argv[]) 1710{ 1711 errcode_t retval; 1712 int err; 1713 1714 if (common_extent_args_process(argc, argv, 1, 1, "delete_node", 1715 "", CHECK_FS_RW | CHECK_FS_BITMAPS)) 1716 return; 1717 1718 retval = ext2fs_extent_delete(current_handle, 0); 1719 if (retval) { 1720 com_err(argv[0], retval, 0); 1721 return; 1722 } 1723 if (current_handle->path && current_handle->path[0].curr) 1724 do_current_node(argc, argv); 1725} 1726 1727void do_replace_node(int argc, char *argv[]) 1728{ 1729 const char *usage = "[--uninit] <lblk> <len> <pblk>"; 1730 errcode_t retval; 1731 struct ext2fs_extent extent; 1732 int err; 1733 1734 if (common_extent_args_process(argc, argv, 3, 5, "replace_node", 1735 usage, CHECK_FS_RW | CHECK_FS_BITMAPS)) 1736 return; 1737 1738 extent.e_flags = 0; 1739 1740 if (!strcmp(argv[1], "--uninit")) { 1741 argc--; 1742 argv++; 1743 extent.e_flags |= EXT2_EXTENT_FLAGS_UNINIT; 1744 } 1745 1746 if (argc != 4) { 1747 fprintf(stderr, "Usage: %s %s\n", argv[0], usage); 1748 return; 1749 } 1750 1751 extent.e_lblk = parse_ulong(argv[1], argv[0], "logical block", &err); 1752 if (err) 1753 return; 1754 1755 extent.e_len = parse_ulong(argv[2], argv[0], "logical block", &err); 1756 if (err) 1757 return; 1758 1759 extent.e_pblk = parse_ulong(argv[3], argv[0], "logical block", &err); 1760 if (err) 1761 return; 1762 1763 retval = ext2fs_extent_replace(current_handle, 0, &extent); 1764 if (retval) { 1765 com_err(argv[0], retval, 0); 1766 return; 1767 } 1768 do_current_node(argc, argv); 1769} 1770 1771void do_split_node(int argc, char *argv[]) 1772{ 1773 errcode_t retval; 1774 struct ext2fs_extent extent; 1775 int err; 1776 1777 if (common_extent_args_process(argc, argv, 1, 1, "split_node", 1778 "", CHECK_FS_RW | CHECK_FS_BITMAPS)) 1779 return; 1780 1781 retval = extent_node_split(current_handle); 1782 if (retval) { 1783 com_err(argv[0], retval, 0); 1784 return; 1785 } 1786 do_current_node(argc, argv); 1787} 1788 1789void do_insert_node(int argc, char *argv[]) 1790{ 1791 const char *usage = "[--after] [--uninit] <lblk> <len> <pblk>"; 1792 errcode_t retval; 1793 struct ext2fs_extent extent; 1794 char *cmd; 1795 int err; 1796 int flags = 0; 1797 1798 if (common_extent_args_process(argc, argv, 3, 6, "insert_node", 1799 usage, CHECK_FS_RW | CHECK_FS_BITMAPS)) 1800 return; 1801 1802 cmd = argv[0]; 1803 1804 extent.e_flags = 0; 1805 1806 while (argc > 2) { 1807 if (!strcmp(argv[1], "--after")) { 1808 argc--; 1809 argv++; 1810 flags |= EXT2_EXTENT_INSERT_AFTER; 1811 continue; 1812 } 1813 if (!strcmp(argv[1], "--uninit")) { 1814 argc--; 1815 argv++; 1816 extent.e_flags |= EXT2_EXTENT_FLAGS_UNINIT; 1817 continue; 1818 } 1819 break; 1820 } 1821 1822 if (argc != 4) { 1823 fprintf(stderr, "usage: %s %s\n", cmd, usage); 1824 return; 1825 } 1826 1827 extent.e_lblk = parse_ulong(argv[1], cmd, 1828 "logical block", &err); 1829 if (err) 1830 return; 1831 1832 extent.e_len = parse_ulong(argv[2], cmd, 1833 "length", &err); 1834 if (err) 1835 return; 1836 1837 extent.e_pblk = parse_ulong(argv[3], cmd, 1838 "pysical block", &err); 1839 if (err) 1840 return; 1841 1842 retval = ext2fs_extent_insert(current_handle, flags, &extent); 1843 if (retval) { 1844 com_err(cmd, retval, 0); 1845 return; 1846 } 1847 do_current_node(argc, argv); 1848} 1849 1850void do_set_bmap(int argc, char **argv) 1851{ 1852 const char *usage = "[--uninit] <lblk> <pblk>"; 1853 errcode_t retval; 1854 blk_t logical; 1855 blk_t physical; 1856 char *cmd = argv[0]; 1857 int flags = 0; 1858 int err; 1859 1860 if (common_extent_args_process(argc, argv, 3, 5, "set_bmap", 1861 usage, CHECK_FS_RW | CHECK_FS_BITMAPS)) 1862 return; 1863 1864 if (argc > 2 && !strcmp(argv[1], "--uninit")) { 1865 argc--; 1866 argv++; 1867 flags |= EXT2_EXTENT_SET_BMAP_UNINIT; 1868 } 1869 1870 if (argc != 3) { 1871 fprintf(stderr, "Usage: %s %s\n", cmd, usage); 1872 return; 1873 } 1874 1875 logical = parse_ulong(argv[1], cmd, 1876 "logical block", &err); 1877 if (err) 1878 return; 1879 1880 physical = parse_ulong(argv[2], cmd, 1881 "physical block", &err); 1882 if (err) 1883 return; 1884 1885 retval = ext2fs_extent_set_bmap(current_handle, logical, 1886 (blk64_t) physical, flags); 1887 if (retval) { 1888 com_err(cmd, retval, 0); 1889 return; 1890 } 1891 if (current_handle->path && current_handle->path[0].curr) 1892 do_current_node(argc, argv); 1893} 1894 1895void do_print_all(int argc, char **argv) 1896{ 1897 const char *usage = "[--leaf-only|--reverse|--reverse-leaf]"; 1898 struct ext2fs_extent extent; 1899 errcode_t retval; 1900 errcode_t end_err = EXT2_ET_EXTENT_NO_NEXT; 1901 int op = EXT2_EXTENT_NEXT; 1902 int first_op = EXT2_EXTENT_ROOT; 1903 1904 1905 if (common_extent_args_process(argc, argv, 1, 2, "print_all", 1906 usage, 0)) 1907 return; 1908 1909 if (argc == 2) { 1910 if (!strcmp(argv[1], "--leaf-only")) 1911 op = EXT2_EXTENT_NEXT_LEAF; 1912 else if (!strcmp(argv[1], "--reverse")) { 1913 op = EXT2_EXTENT_PREV; 1914 first_op = EXT2_EXTENT_LAST_LEAF; 1915 end_err = EXT2_ET_EXTENT_NO_PREV; 1916 } else if (!strcmp(argv[1], "--reverse-leaf")) { 1917 op = EXT2_EXTENT_PREV_LEAF; 1918 first_op = EXT2_EXTENT_LAST_LEAF; 1919 end_err = EXT2_ET_EXTENT_NO_PREV; 1920 } else { 1921 fprintf(stderr, "Usage: %s %s\n", argv[0], usage); 1922 return; 1923 } 1924 } 1925 1926 retval = ext2fs_extent_get(current_handle, first_op, &extent); 1927 if (retval) { 1928 com_err(argv[0], retval, 0); 1929 return; 1930 } 1931 dbg_print_extent(0, &extent); 1932 1933 while (1) { 1934 retval = ext2fs_extent_get(current_handle, op, &extent); 1935 if (retval == end_err) 1936 break; 1937 1938 if (retval) { 1939 com_err(argv[0], retval, 0); 1940 return; 1941 } 1942 dbg_print_extent(0, &extent); 1943 } 1944} 1945 1946void do_info(int argc, char **argv) 1947{ 1948 struct ext2fs_extent extent; 1949 struct ext2_extent_info info; 1950 errcode_t retval; 1951 1952 if (common_extent_args_process(argc, argv, 1, 1, "info", "", 0)) 1953 return; 1954 1955 retval = ext2fs_extent_get_info(current_handle, &info); 1956 if (retval) { 1957 com_err(argv[0], retval, 0); 1958 return; 1959 } 1960 1961 retval = ext2fs_extent_get(current_handle, 1962 EXT2_EXTENT_CURRENT, &extent); 1963 if (retval) { 1964 com_err(argv[0], retval, 0); 1965 return; 1966 } 1967 1968 dbg_print_extent(0, &extent); 1969 1970 printf("Current handle location: %d/%d (max: %d, bytes %d), level %d/%d\n", 1971 info.curr_entry, info.num_entries, info.max_entries, 1972 info.bytes_avail, info.curr_level, info.max_depth); 1973 printf("\tmax lblk: %llu, max pblk: %llu\n", info.max_lblk, 1974 info.max_pblk); 1975 printf("\tmax_len: %u, max_uninit_len: %u\n", info.max_len, 1976 info.max_uninit_len); 1977} 1978 1979void do_goto_block(int argc, char **argv) 1980{ 1981 struct ext2fs_extent extent; 1982 errcode_t retval; 1983 int op = EXT2_EXTENT_NEXT_LEAF; 1984 blk64_t blk; 1985 int level = 0, err; 1986 1987 if (common_extent_args_process(argc, argv, 2, 3, "goto_block", 1988 "block [level]", 0)) 1989 return; 1990 1991 if (strtoblk(argv[0], argv[1], &blk)) 1992 return; 1993 1994 if (argc == 3) { 1995 level = parse_ulong(argv[2], argv[0], "level", &err); 1996 if (err) 1997 return; 1998 } 1999 2000 retval = extent_goto(current_handle, level, (blk64_t) blk); 2001 2002 if (retval) { 2003 com_err(argv[0], retval, 2004 "while trying to go to block %llu, level %d", 2005 (unsigned long long) blk, level); 2006 return; 2007 } 2008 2009 generic_goto_node(argv[0], EXT2_EXTENT_CURRENT); 2010} 2011#endif 2012 2013