extent.c revision 83d9be1d5daf170066dd0e74afdd8e7063c1855e
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 Public 8 * License. 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#include "ss/ss.h" 31 32/* 33 * Definitions to be dropped in lib/ext2fs/ext2fs.h 34 */ 35 36/* 37 * Private definitions 38 */ 39 40struct extent_path { 41 char *buf; 42 int entries; 43 int max_entries; 44 int left; 45 int visit_num; 46 int flags; 47 blk64_t end_blk; 48 void *curr; 49}; 50 51 52struct ext2_extent_handle { 53 errcode_t magic; 54 ext2_filsys fs; 55 ext2_ino_t ino; 56 struct ext2_inode *inode; 57 int type; 58 int level; 59 int max_depth; 60 struct extent_path *path; 61}; 62 63struct ext2_extent_path { 64 errcode_t magic; 65 int leaf_height; 66 blk64_t lblk; 67}; 68 69/* 70 * Useful Debugging stuff 71 */ 72 73#ifdef DEBUG 74static void dbg_show_header(struct ext3_extent_header *eh) 75{ 76 printf("header: magic=%x entries=%u max=%u depth=%u generation=%u\n", 77 eh->eh_magic, eh->eh_entries, eh->eh_max, eh->eh_depth, 78 eh->eh_generation); 79} 80 81static void dbg_show_index(struct ext3_extent_idx *ix) 82{ 83 printf("index: block=%u leaf=%u leaf_hi=%u unused=%u\n", 84 ix->ei_block, ix->ei_leaf, ix->ei_leaf_hi, ix->ei_unused); 85} 86 87static void dbg_show_extent(struct ext3_extent *ex) 88{ 89 printf("extent: block=%u-%u len=%u start=%u start_hi=%u\n", 90 ex->ee_block, ex->ee_block + ex->ee_len - 1, 91 ex->ee_len, ex->ee_start, ex->ee_start_hi); 92} 93 94static void dbg_print_extent(char *desc, struct ext2fs_extent *extent) 95{ 96 if (desc) 97 printf("%s: ", desc); 98 printf("extent: lblk %llu--%llu, len %lu, pblk %llu, flags: ", 99 extent->e_lblk, extent->e_lblk + extent->e_len - 1, 100 extent->e_len, extent->e_pblk); 101 if (extent->e_flags & EXT2_EXTENT_FLAGS_LEAF) 102 fputs("LEAF ", stdout); 103 if (extent->e_flags & EXT2_EXTENT_FLAGS_UNINIT) 104 fputs("UNINIT ", stdout); 105 if (extent->e_flags & EXT2_EXTENT_FLAGS_SECOND_VISIT) 106 fputs("2ND_VISIT ", stdout); 107 if (!extent->e_flags) 108 fputs("(none)", stdout); 109 fputc('\n', stdout); 110 111} 112 113#define dbg_printf(fmt, args...) printf(fmt, ## args) 114#else 115#define dbg_show_header(eh) do { } while (0) 116#define dbg_show_index(ix) do { } while (0) 117#define dbg_show_extent(ex) do { } while (0) 118#define dbg_print_extent(desc, ex) do { } while (0) 119#define dbg_printf(fmt, args...) do { } while (0) 120#endif 121 122/* 123 * Verify the extent header as being sane 124 */ 125errcode_t ext2fs_extent_header_verify(void *ptr, int size) 126{ 127 int eh_max, entry_size; 128 struct ext3_extent_header *eh = ptr; 129 130 dbg_show_header(eh); 131 if (ext2fs_le16_to_cpu(eh->eh_magic) != EXT3_EXT_MAGIC) 132 return EXT2_ET_EXTENT_HEADER_BAD; 133 if (ext2fs_le16_to_cpu(eh->eh_entries) > ext2fs_le16_to_cpu(eh->eh_max)) 134 return EXT2_ET_EXTENT_HEADER_BAD; 135 if (eh->eh_depth == 0) 136 entry_size = sizeof(struct ext3_extent); 137 else 138 entry_size = sizeof(struct ext3_extent_idx); 139 140 eh_max = (size - sizeof(*eh)) / entry_size; 141 /* Allow two extent-sized items at the end of the block, for 142 * ext4_extent_tail with checksum in the future. */ 143 if ((ext2fs_le16_to_cpu(eh->eh_max) > eh_max) || 144 (ext2fs_le16_to_cpu(eh->eh_max) < (eh_max - 2))) 145 return EXT2_ET_EXTENT_HEADER_BAD; 146 147 return 0; 148} 149 150 151/* 152 * Begin functions to handle an inode's extent information 153 */ 154 155extern void ext2fs_extent_free(ext2_extent_handle_t handle) 156{ 157 int i; 158 159 if (!handle) 160 return; 161 162 if (handle->inode) 163 ext2fs_free_mem(&handle->inode); 164 if (handle->path) { 165 for (i=1; i < handle->max_depth; i++) { 166 if (handle->path[i].buf) 167 ext2fs_free_mem(&handle->path[i].buf); 168 } 169 ext2fs_free_mem(&handle->path); 170 } 171 ext2fs_free_mem(&handle); 172} 173 174extern errcode_t ext2fs_extent_open(ext2_filsys fs, ext2_ino_t ino, 175 ext2_extent_handle_t *ret_handle) 176{ 177 struct ext2_extent_handle *handle; 178 errcode_t retval; 179 int isize = EXT2_INODE_SIZE(fs->super); 180 struct ext3_extent_header *eh; 181 struct ext3_extent_idx *ix; 182 183 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 184 185 if ((ino == 0) || (ino > fs->super->s_inodes_count)) 186 return EXT2_ET_BAD_INODE_NUM; 187 188 retval = ext2fs_get_mem(sizeof(struct ext2_extent_handle), &handle); 189 if (retval) 190 return retval; 191 memset(handle, 0, sizeof(struct ext2_extent_handle)); 192 193 retval = ext2fs_get_mem(isize, &handle->inode); 194 if (retval) 195 goto errout; 196 197 handle->ino = ino; 198 handle->fs = fs; 199 200 retval = ext2fs_read_inode_full(fs, ino, handle->inode, isize); 201 if (retval) 202 goto errout; 203 204 if (!(handle->inode->i_flags & EXT4_EXTENTS_FL)) 205 return EXT2_ET_INODE_NOT_EXTENT; 206 207 eh = (struct ext3_extent_header *) &handle->inode->i_block; 208 209 retval = ext2fs_extent_header_verify(eh, sizeof(handle->inode->i_block)); 210 if (retval) 211 return (retval); 212 213 handle->max_depth = ext2fs_le16_to_cpu(eh->eh_depth); 214 handle->type = ext2fs_le16_to_cpu(eh->eh_magic); 215 216 retval = ext2fs_get_mem(((handle->max_depth+1) * 217 sizeof(struct extent_path)), 218 &handle->path); 219 memset(handle->path, 0, 220 (handle->max_depth+1) * sizeof(struct extent_path)); 221 handle->path[0].buf = (char *) handle->inode->i_block; 222 223 handle->path[0].left = handle->path[0].entries = 224 ext2fs_le16_to_cpu(eh->eh_entries); 225 handle->path[0].max_entries = ext2fs_le16_to_cpu(eh->eh_max); 226 handle->path[0].curr = 0; 227 handle->path[0].end_blk = 228 ((((__u64) handle->inode->i_size_high << 32) + 229 handle->inode->i_size + (fs->blocksize - 1)) 230 >> EXT2_BLOCK_SIZE_BITS(fs->super)); 231 handle->path[0].visit_num = 1; 232 handle->level = 0; 233 handle->magic = EXT2_ET_MAGIC_EXTENT_HANDLE; 234 235 *ret_handle = handle; 236 return 0; 237 238errout: 239 ext2fs_extent_free(handle); 240 return retval; 241} 242 243/* 244 * This function is responsible for (optionally) moving through the 245 * extent tree and then returning the current extent 246 */ 247errcode_t ext2fs_extent_get(ext2_extent_handle_t handle, 248 int flags, struct ext2fs_extent *extent) 249{ 250 struct extent_path *path, *newpath; 251 struct ext3_extent_header *eh; 252 struct ext3_extent_idx *ix = 0; 253 struct ext3_extent *ex; 254 errcode_t retval; 255 blk_t blk; 256 blk64_t end_blk; 257 int orig_op, op; 258 259 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 260 261 if (!handle->path) 262 return EXT2_ET_NO_CURRENT_NODE; 263 264 orig_op = op = flags & EXT2_EXTENT_MOVE_MASK; 265 266retry: 267 path = handle->path + handle->level; 268 if ((orig_op == EXT2_EXTENT_NEXT) || 269 (orig_op == EXT2_EXTENT_NEXT_LEAF)) { 270 if (handle->level < handle->max_depth) { 271 /* interior node */ 272 if (path->visit_num == 0) { 273 path->visit_num++; 274 op = EXT2_EXTENT_DOWN; 275 } else if (path->left > 0) 276 op = EXT2_EXTENT_NEXT_SIB; 277 else if (handle->level > 0) 278 op = EXT2_EXTENT_UP; 279 else 280 return EXT2_ET_EXTENT_NO_NEXT; 281 } else { 282 /* leaf node */ 283 if (path->left > 0) 284 op = EXT2_EXTENT_NEXT_SIB; 285 else if (handle->level > 0) 286 op = EXT2_EXTENT_UP; 287 else 288 return EXT2_ET_EXTENT_NO_NEXT; 289 } 290 if (op != EXT2_EXTENT_NEXT_SIB) { 291 dbg_printf("<<<< OP = %s\n", 292 (op == EXT2_EXTENT_DOWN) ? "down" : 293 ((op == EXT2_EXTENT_UP) ? "up" : "unknown")); 294 } 295 } 296 297 if ((orig_op == EXT2_EXTENT_PREV) || 298 (orig_op == EXT2_EXTENT_PREV_LEAF)) { 299 if (handle->level < handle->max_depth) { 300 /* interior node */ 301 if (path->visit_num > 0 ) { 302 /* path->visit_num = 0; */ 303 op = EXT2_EXTENT_DOWN_AND_LAST; 304 } else if (path->left < path->entries-1) 305 op = EXT2_EXTENT_PREV_SIB; 306 else if (handle->level > 0) 307 op = EXT2_EXTENT_UP; 308 else 309 return EXT2_ET_EXTENT_NO_PREV; 310 } else { 311 /* leaf node */ 312 if (path->left < path->entries-1) 313 op = EXT2_EXTENT_PREV_SIB; 314 else if (handle->level > 0) 315 op = EXT2_EXTENT_UP; 316 else 317 return EXT2_ET_EXTENT_NO_PREV; 318 } 319 if (op != EXT2_EXTENT_PREV_SIB) { 320 dbg_printf("<<<< OP = %s\n", 321 (op == EXT2_EXTENT_DOWN_AND_LAST) ? "down/last" : 322 ((op == EXT2_EXTENT_UP) ? "up" : "unknown")); 323 } 324 } 325 326 if (orig_op == EXT2_EXTENT_LAST_LEAF) { 327 if ((handle->level < handle->max_depth) && 328 (path->left == 0)) 329 op = EXT2_EXTENT_DOWN; 330 else 331 op = EXT2_EXTENT_LAST_SIB; 332 dbg_printf("<<<< OP = %s\n", 333 (op == EXT2_EXTENT_DOWN) ? "down" : "last_sib"); 334 } 335 336 switch (op) { 337 case EXT2_EXTENT_CURRENT: 338 ix = path->curr; 339 break; 340 case EXT2_EXTENT_ROOT: 341 handle->level = 0; 342 path = handle->path + handle->level; 343 case EXT2_EXTENT_FIRST_SIB: 344 path->left = path->entries; 345 path->curr = 0; 346 case EXT2_EXTENT_NEXT_SIB: 347 if (path->left <= 0) 348 return EXT2_ET_EXTENT_NO_NEXT; 349 if (path->curr) { 350 ix = path->curr; 351 ix++; 352 } else { 353 eh = (struct ext3_extent_header *) path->buf; 354 ix = EXT_FIRST_INDEX(eh); 355 } 356 path->left--; 357 path->curr = ix; 358 path->visit_num = 0; 359 break; 360 case EXT2_EXTENT_PREV_SIB: 361 if (!path->curr || 362 path->left+1 >= path->entries) 363 return EXT2_ET_EXTENT_NO_PREV; 364 ix = path->curr; 365 ix--; 366 path->curr = ix; 367 path->left++; 368 if (handle->level < handle->max_depth) 369 path->visit_num = 1; 370 break; 371 case EXT2_EXTENT_LAST_SIB: 372 eh = (struct ext3_extent_header *) path->buf; 373 path->curr = EXT_LAST_EXTENT(eh); 374 ix = path->curr; 375 path->left = 0; 376 path->visit_num = 0; 377 break; 378 case EXT2_EXTENT_UP: 379 if (handle->level <= 0) 380 return EXT2_ET_EXTENT_NO_UP; 381 handle->level--; 382 path--; 383 ix = path->curr; 384 if ((orig_op == EXT2_EXTENT_PREV) || 385 (orig_op == EXT2_EXTENT_PREV_LEAF)) 386 path->visit_num = 0; 387 break; 388 case EXT2_EXTENT_DOWN: 389 case EXT2_EXTENT_DOWN_AND_LAST: 390 if (!path->curr ||(handle->level >= handle->max_depth)) 391 return EXT2_ET_EXTENT_NO_DOWN; 392 393 ix = path->curr; 394 newpath = path + 1; 395 if (!newpath->buf) { 396 retval = ext2fs_get_mem(handle->fs->blocksize, 397 &newpath->buf); 398 if (retval) 399 return retval; 400 } 401 blk = ext2fs_le32_to_cpu(ix->ei_leaf) + 402 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32); 403 if ((handle->fs->flags & EXT2_FLAG_IMAGE_FILE) && 404 (handle->fs->io != handle->fs->image_io)) 405 memset(newpath->buf, 0, handle->fs->blocksize); 406 else { 407 retval = io_channel_read_blk(handle->fs->io, 408 blk, 1, newpath->buf); 409 if (retval) 410 return retval; 411 } 412 handle->level++; 413 414 eh = (struct ext3_extent_header *) newpath->buf; 415 416 retval = ext2fs_extent_header_verify(eh, handle->fs->blocksize); 417 if (retval) 418 return retval; 419 420 newpath->left = newpath->entries = 421 ext2fs_le16_to_cpu(eh->eh_entries); 422 newpath->max_entries = ext2fs_le16_to_cpu(eh->eh_max); 423 424 if (path->left > 0) { 425 ix++; 426 newpath->end_blk = ext2fs_le32_to_cpu(ix->ei_block); 427 } else 428 newpath->end_blk = path->end_blk; 429 430 path = newpath; 431 if (op == EXT2_EXTENT_DOWN) { 432 ix = EXT_FIRST_INDEX((struct ext3_extent_header *) eh); 433 path->curr = ix; 434 path->left = path->entries - 1; 435 path->visit_num = 0; 436 } else { 437 ix = EXT_LAST_INDEX((struct ext3_extent_header *) eh); 438 path->curr = ix; 439 path->left = 0; 440 if (handle->level < handle->max_depth) 441 path->visit_num = 1; 442 } 443 444 dbg_printf("Down to level %d/%d, end_blk=%llu\n", 445 handle->level, handle->max_depth, 446 path->end_blk); 447 448 break; 449 default: 450 return EXT2_ET_OP_NOT_SUPPORTED; 451 } 452 453 if (!ix) 454 return EXT2_ET_NO_CURRENT_NODE; 455 456 extent->e_flags = 0; 457 458 if (handle->level == handle->max_depth) { 459 ex = (struct ext3_extent *) ix; 460 461 extent->e_pblk = ext2fs_le32_to_cpu(ex->ee_start) + 462 ((__u64) ext2fs_le16_to_cpu(ex->ee_start_hi) << 32); 463 extent->e_lblk = ext2fs_le32_to_cpu(ex->ee_block); 464 extent->e_len = ext2fs_le16_to_cpu(ex->ee_len); 465 extent->e_flags = EXT2_EXTENT_FLAGS_LEAF; 466 if (extent->e_len > EXT_INIT_MAX_LEN) { 467 extent->e_len -= EXT_INIT_MAX_LEN; 468 extent->e_flags = EXT2_EXTENT_FLAGS_UNINIT; 469 } 470 } else { 471 extent->e_pblk = ext2fs_le32_to_cpu(ix->ei_leaf) + 472 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32); 473 extent->e_lblk = ext2fs_le32_to_cpu(ix->ei_block); 474 if (path->left > 0) { 475 ix++; 476 end_blk = ext2fs_le32_to_cpu(ix->ei_block); 477 } else 478 end_blk = path->end_blk; 479 480 extent->e_len = end_blk - extent->e_lblk; 481 } 482 if (path->visit_num) 483 extent->e_flags |= EXT2_EXTENT_FLAGS_SECOND_VISIT; 484 485 if (((orig_op == EXT2_EXTENT_NEXT_LEAF) || 486 (orig_op == EXT2_EXTENT_PREV_LEAF)) && 487 (handle->level != handle->max_depth)) 488 goto retry; 489 490 if ((orig_op == EXT2_EXTENT_LAST_LEAF) && 491 ((handle->level != handle->max_depth) || 492 (path->left != 0))) 493 goto retry; 494 495 return 0; 496} 497 498static errcode_t update_path(ext2_extent_handle_t handle) 499{ 500 struct extent_path *path; 501 blk64_t blk; 502 errcode_t retval; 503 struct ext3_extent_idx *ix; 504 505 if (handle->level == 0) { 506 retval = ext2fs_write_inode_full(handle->fs, handle->ino, 507 handle->inode, EXT2_INODE_SIZE(handle->fs->super)); 508 } else { 509 ix = handle->path[handle->level - 1].curr; 510 blk = ext2fs_le32_to_cpu(ix->ei_leaf) + 511 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32); 512 513 retval = io_channel_write_blk(handle->fs->io, 514 blk, 1, handle->path[handle->level].buf); 515 } 516 return retval; 517} 518 519errcode_t ext2fs_extent_save_path(ext2_extent_handle_t handle, 520 ext2_extent_path_t *ret_path) 521{ 522 ext2_extent_path_t save_path; 523 struct ext2fs_extent extent; 524 struct ext2_extent_info info; 525 errcode_t retval; 526 527 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent); 528 if (retval) 529 return retval; 530 531 retval = ext2fs_extent_get_info(handle, &info); 532 if (retval) 533 return retval; 534 535 retval = ext2fs_get_mem(sizeof(struct ext2_extent_path), &save_path); 536 if (retval) 537 return retval; 538 memset(save_path, 0, sizeof(struct ext2_extent_path)); 539 540 save_path->magic = EXT2_ET_MAGIC_EXTENT_PATH; 541 save_path->leaf_height = info.max_depth - info.curr_level - 1; 542 save_path->lblk = extent.e_lblk; 543 544 *ret_path = save_path; 545 return 0; 546} 547 548errcode_t ext2fs_extent_free_path(ext2_extent_path_t path) 549{ 550 EXT2_CHECK_MAGIC(path, EXT2_ET_MAGIC_EXTENT_PATH); 551 552 ext2fs_free_mem(&path); 553 return 0; 554} 555 556static errcode_t extent_goto(ext2_extent_handle_t handle, 557 int leaf_level, blk64_t blk) 558{ 559 struct ext2fs_extent extent, next; 560 errcode_t retval; 561 562 retval = ext2fs_extent_get(handle, EXT2_EXTENT_ROOT, &extent); 563 if (retval) 564 return retval; 565 566 dbg_print_extent("root", &extent); 567 while (1) { 568 if (handle->level - leaf_level == handle->max_depth) { 569 if ((blk >= extent.e_lblk) && 570 (blk < extent.e_lblk + extent.e_len)) 571 return 0; 572 if (blk < extent.e_lblk) 573 return EXT2_ET_EXTENT_NOT_FOUND; 574 retval = ext2fs_extent_get(handle, 575 EXT2_EXTENT_NEXT_SIB, 576 &extent); 577 if (retval == EXT2_ET_EXTENT_NO_NEXT) 578 return EXT2_ET_EXTENT_NOT_FOUND; 579 if (retval) 580 return retval; 581 continue; 582 } 583 584 retval = ext2fs_extent_get(handle, EXT2_EXTENT_NEXT_SIB, 585 &extent); 586 if (retval == EXT2_ET_EXTENT_NO_NEXT) 587 goto go_down; 588 if (retval) 589 return retval; 590 591 dbg_print_extent("next", &extent); 592 if (blk == extent.e_lblk) 593 goto go_down; 594 if (blk > extent.e_lblk) 595 continue; 596 597 retval = ext2fs_extent_get(handle, EXT2_EXTENT_PREV_SIB, 598 &extent); 599 if (retval) 600 return retval; 601 602 dbg_print_extent("prev", &extent); 603 604 go_down: 605 retval = ext2fs_extent_get(handle, EXT2_EXTENT_DOWN, 606 &extent); 607 if (retval) 608 return retval; 609 610 dbg_print_extent("down", &extent); 611 } 612} 613 614errcode_t ext2fs_extent_goto(ext2_extent_handle_t handle, 615 blk64_t blk) 616{ 617 return extent_goto(handle, 0, blk); 618} 619 620errcode_t ext2fs_extent_replace(ext2_extent_handle_t handle, int flags, 621 struct ext2fs_extent *extent) 622{ 623 struct extent_path *path; 624 struct ext3_extent_idx *ix; 625 struct ext3_extent *ex; 626 627 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 628 629 if (!(handle->fs->flags & EXT2_FLAG_RW)) 630 return EXT2_ET_RO_FILSYS; 631 632 if (!handle->path) 633 return EXT2_ET_NO_CURRENT_NODE; 634 635 path = handle->path + handle->level; 636 if (!path->curr) 637 return EXT2_ET_NO_CURRENT_NODE; 638 639 if (handle->level == handle->max_depth) { 640 ex = path->curr; 641 642 ex->ee_block = ext2fs_cpu_to_le32(extent->e_lblk); 643 ex->ee_start = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF); 644 ex->ee_start_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32); 645 ex->ee_len = ext2fs_cpu_to_le16(extent->e_len); 646 } else { 647 ix = path->curr; 648 649 ix->ei_leaf = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF); 650 ix->ei_leaf_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32); 651 ix->ei_block = ext2fs_cpu_to_le32(extent->e_lblk); 652 ix->ei_unused = 0; 653 } 654 update_path(handle); 655 return 0; 656} 657 658errcode_t ext2fs_extent_insert(ext2_extent_handle_t handle, int flags, 659 struct ext2fs_extent *extent) 660{ 661 struct extent_path *path; 662 struct ext3_extent_idx *ix; 663 struct ext3_extent_header *eh; 664 errcode_t retval; 665 666 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 667 668 if (!(handle->fs->flags & EXT2_FLAG_RW)) 669 return EXT2_ET_RO_FILSYS; 670 671 if (!handle->path) 672 return EXT2_ET_NO_CURRENT_NODE; 673 674 path = handle->path + handle->level; 675 676 if (path->entries >= path->max_entries) 677 return EXT2_ET_CANT_INSERT_EXTENT; 678 679 eh = (struct ext3_extent_header *) path->buf; 680 if (path->curr) { 681 ix = path->curr; 682 if (flags & EXT2_EXTENT_INSERT_AFTER) { 683 ix++; 684 path->left--; 685 } 686 } else 687 ix = EXT_FIRST_INDEX(eh); 688 689 path->curr = ix; 690 691 if (path->left > 0) 692 memmove(ix + 1, ix, 693 path->left * sizeof(struct ext3_extent_idx)); 694 path->left++; 695 path->entries++; 696 697 eh = (struct ext3_extent_header *) path->buf; 698 eh->eh_entries = ext2fs_cpu_to_le16(path->entries); 699 700 retval = ext2fs_extent_replace(handle, 0, extent); 701 if (retval) 702 goto errout; 703 704 retval = update_path(handle); 705 if (retval) 706 goto errout; 707 708 return 0; 709 710errout: 711 ext2fs_extent_delete(handle, 0); 712 return retval; 713} 714 715errcode_t ext2fs_extent_delete(ext2_extent_handle_t handle, int flags) 716{ 717 struct extent_path *path; 718 char *cp; 719 struct ext3_extent_header *eh; 720 errcode_t retval; 721 722 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 723 724 if (!(handle->fs->flags & EXT2_FLAG_RW)) 725 return EXT2_ET_RO_FILSYS; 726 727 if (!handle->path) 728 return EXT2_ET_NO_CURRENT_NODE; 729 730 path = handle->path + handle->level; 731 if (!path->curr) 732 return EXT2_ET_NO_CURRENT_NODE; 733 734 cp = path->curr; 735 736 if (path->left) { 737 memmove(cp, cp + sizeof(struct ext3_extent_idx), 738 path->left * sizeof(struct ext3_extent_idx)); 739 path->left--; 740 } else { 741 struct ext3_extent_idx *ix = path->curr; 742 ix--; 743 path->curr = ix; 744 } 745 path->entries--; 746 if (path->entries == 0) 747 path->curr = 0; 748 749 eh = (struct ext3_extent_header *) path->buf; 750 eh->eh_entries = ext2fs_cpu_to_le16(path->entries); 751 752 retval = update_path(handle); 753 754 return retval; 755} 756 757errcode_t ext2fs_extent_get_info(ext2_extent_handle_t handle, 758 struct ext2_extent_info *info) 759{ 760 struct extent_path *path; 761 struct ext3_extent_idx *ix; 762 struct ext3_extent *ex; 763 764 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 765 766 memset(info, 0, sizeof(struct ext2_extent_info)); 767 768 path = handle->path + handle->level; 769 if (path) { 770 if (path->curr) 771 info->curr_entry = ((char *) path->curr - path->buf) / 772 sizeof(struct ext3_extent_idx); 773 else 774 info->curr_entry = 0; 775 info->num_entries = path->entries; 776 info->max_entries = path->max_entries; 777 info->bytes_avail = (path->max_entries - path->entries) * 778 sizeof(struct ext3_extent); 779 } 780 781 info->curr_level = handle->level; 782 info->max_depth = handle->max_depth; 783 info->max_lblk = ((__u64) 1 << 32) - 1; 784 info->max_pblk = ((__u64) 1 << 48) - 1; 785 info->max_len = (1UL << 15); 786 info->max_uninit_len = (1UL << 15) - 1; 787 788 return 0; 789} 790 791#ifdef DEBUG 792 793#include "debugfs.h" 794 795/* 796 * Hook in new commands into debugfs 797 */ 798char *debug_prog_name = "tst_extents"; 799extern ss_request_table extent_cmds; 800ss_request_table *extra_cmds = &extent_cmds; 801 802ext2_ino_t current_ino = 0; 803ext2_extent_handle_t current_handle; 804 805void do_inode(int argc, char *argv[]) 806{ 807 ext2_ino_t inode; 808 int i; 809 struct ext3_extent_header *eh; 810 errcode_t retval; 811 812 if (check_fs_open(argv[0])) 813 return; 814 815 if (argc == 1) { 816 if (current_ino) 817 printf("Current inode is %d\n", current_ino); 818 else 819 printf("No current inode\n"); 820 return; 821 } 822 823 if (common_inode_args_process(argc, argv, &inode, 0)) { 824 return; 825 } 826 827 current_ino = 0; 828 829 retval = ext2fs_extent_open(current_fs, inode, ¤t_handle); 830 if (retval) { 831 com_err(argv[1], retval, "while opening extent handle"); 832 return; 833 } 834 835 current_ino = inode; 836 837 printf("Loaded inode %d\n", current_ino); 838 839 return; 840} 841 842void generic_goto_node(char *cmd_name, int op) 843{ 844 struct ext2fs_extent extent; 845 errcode_t retval; 846 847 if (check_fs_open(cmd_name)) 848 return; 849 850 if (!current_handle) { 851 com_err(cmd_name, 0, "Extent handle not open"); 852 return; 853 } 854 855 retval = ext2fs_extent_get(current_handle, op, &extent); 856 if (retval) { 857 com_err(cmd_name, retval, 0); 858 return; 859 } 860 dbg_print_extent(0, &extent); 861} 862 863void do_current_node(int argc, char *argv[]) 864{ 865 generic_goto_node(argv[0], EXT2_EXTENT_CURRENT); 866} 867 868void do_root_node(int argc, char *argv[]) 869{ 870 generic_goto_node(argv[0], EXT2_EXTENT_ROOT); 871} 872 873void do_last_leaf(int argc, char *argv[]) 874{ 875 generic_goto_node(argv[0], EXT2_EXTENT_LAST_LEAF); 876} 877 878void do_first_sib(int argc, char *argv[]) 879{ 880 generic_goto_node(argv[0], EXT2_EXTENT_FIRST_SIB); 881} 882 883void do_last_sib(int argc, char *argv[]) 884{ 885 generic_goto_node(argv[0], EXT2_EXTENT_LAST_SIB); 886} 887 888void do_next_sib(int argc, char *argv[]) 889{ 890 generic_goto_node(argv[0], EXT2_EXTENT_NEXT_SIB); 891} 892 893void do_prev_sib(int argc, char *argv[]) 894{ 895 generic_goto_node(argv[0], EXT2_EXTENT_PREV_SIB); 896} 897 898void do_next_leaf(int argc, char *argv[]) 899{ 900 generic_goto_node(argv[0], EXT2_EXTENT_NEXT_LEAF); 901} 902 903void do_prev_leaf(int argc, char *argv[]) 904{ 905 generic_goto_node(argv[0], EXT2_EXTENT_PREV_LEAF); 906} 907 908void do_next(int argc, char *argv[]) 909{ 910 generic_goto_node(argv[0], EXT2_EXTENT_NEXT); 911} 912 913void do_prev(int argc, char *argv[]) 914{ 915 generic_goto_node(argv[0], EXT2_EXTENT_PREV); 916} 917 918void do_up(int argc, char *argv[]) 919{ 920 generic_goto_node(argv[0], EXT2_EXTENT_UP); 921} 922 923void do_down(int argc, char *argv[]) 924{ 925 generic_goto_node(argv[0], EXT2_EXTENT_DOWN); 926} 927 928void do_delete_node(int argc, char *argv[]) 929{ 930 errcode_t retval; 931 int err; 932 933 if (check_fs_read_write(argv[0])) 934 return; 935 936 retval = ext2fs_extent_delete(current_handle, 0); 937 if (retval) { 938 com_err(argv[0], retval, 0); 939 return; 940 } 941 do_current_node(argc, argv); 942} 943 944void do_replace_node(int argc, char *argv[]) 945{ 946 errcode_t retval; 947 struct ext2fs_extent extent; 948 int err; 949 950 if (check_fs_read_write(argv[0])) 951 return; 952 953 if (argc != 4) { 954 fprintf(stderr, "usage: %s <lblk> <len> <pblk>\n", argv[0]); 955 return; 956 } 957 958 extent.e_lblk = parse_ulong(argv[1], argv[0], 959 "logical block", &err); 960 if (err) 961 return; 962 963 extent.e_len = parse_ulong(argv[2], argv[0], 964 "logical block", &err); 965 if (err) 966 return; 967 968 extent.e_pblk = parse_ulong(argv[3], argv[0], 969 "logical block", &err); 970 if (err) 971 return; 972 973 retval = ext2fs_extent_replace(current_handle, 0, &extent); 974 if (retval) { 975 com_err(argv[0], retval, 0); 976 return; 977 } 978 do_current_node(argc, argv); 979} 980 981void do_insert_node(int argc, char *argv[]) 982{ 983 errcode_t retval; 984 struct ext2fs_extent extent; 985 char *cmd; 986 int err; 987 int flags = 0; 988 989 if (check_fs_read_write(argv[0])) 990 return; 991 992 cmd = argv[0]; 993 994 if (argc > 2 && !strcmp(argv[1], "--after")) { 995 argc--; 996 argv++; 997 flags |= EXT2_EXTENT_INSERT_AFTER; 998 } 999 1000 if (argc != 4) { 1001 fprintf(stderr, "usage: %s <lblk> <len> <pblk>\n", cmd); 1002 return; 1003 } 1004 1005 extent.e_lblk = parse_ulong(argv[1], cmd, 1006 "logical block", &err); 1007 if (err) 1008 return; 1009 1010 extent.e_len = parse_ulong(argv[2], cmd, 1011 "length", &err); 1012 if (err) 1013 return; 1014 1015 extent.e_pblk = parse_ulong(argv[3], cmd, 1016 "pysical block", &err); 1017 if (err) 1018 return; 1019 1020 retval = ext2fs_extent_insert(current_handle, flags, &extent); 1021 if (retval) { 1022 com_err(cmd, retval, 0); 1023 return; 1024 } 1025 do_current_node(argc, argv); 1026} 1027 1028void do_print_all(int argc, char **argv) 1029{ 1030 struct ext2fs_extent extent; 1031 errcode_t retval; 1032 errcode_t end_err = EXT2_ET_EXTENT_NO_NEXT; 1033 int op = EXT2_EXTENT_NEXT; 1034 int first_op = EXT2_EXTENT_ROOT; 1035 1036 1037 if (check_fs_open(argv[0])) 1038 return; 1039 1040 if (!current_handle) { 1041 com_err(argv[0], 0, "Extent handle not open"); 1042 return; 1043 } 1044 1045 if (argc > 2) { 1046 print_usage: 1047 fprintf(stderr, 1048 "Usage: %s [--leaf-only|--reverse|--reverse-leaf]\n", 1049 argv[0]); 1050 return; 1051 } 1052 1053 if (argc == 2) { 1054 if (!strcmp(argv[1], "--leaf-only")) 1055 op = EXT2_EXTENT_NEXT_LEAF; 1056 else if (!strcmp(argv[1], "--reverse")) { 1057 op = EXT2_EXTENT_PREV; 1058 first_op = EXT2_EXTENT_LAST_LEAF; 1059 end_err = EXT2_ET_EXTENT_NO_PREV; 1060 } else if (!strcmp(argv[1], "--reverse-leaf")) { 1061 op = EXT2_EXTENT_PREV_LEAF; 1062 first_op = EXT2_EXTENT_LAST_LEAF; 1063 end_err = EXT2_ET_EXTENT_NO_PREV; 1064 } else 1065 goto print_usage; 1066 } 1067 1068 retval = ext2fs_extent_get(current_handle, first_op, &extent); 1069 if (retval) { 1070 com_err(argv[0], retval, 0); 1071 return; 1072 } 1073 dbg_print_extent(0, &extent); 1074 1075 while (1) { 1076 retval = ext2fs_extent_get(current_handle, op, &extent); 1077 if (retval == end_err) 1078 break; 1079 1080 if (retval) { 1081 com_err(argv[0], retval, 0); 1082 return; 1083 } 1084 dbg_print_extent(0, &extent); 1085 } 1086} 1087 1088void do_info(int argc, char **argv) 1089{ 1090 struct ext2_extent_info info; 1091 errcode_t retval; 1092 1093 if (check_fs_open(argv[0])) 1094 return; 1095 1096 if (!current_handle) { 1097 com_err(argv[0], 0, "Extent handle not open"); 1098 return; 1099 } 1100 1101 retval = ext2fs_extent_get_info(current_handle, &info); 1102 if (retval) { 1103 com_err(argv[0], retval, 0); 1104 return; 1105 } 1106 1107 printf("Current handle location: %d/%d (max: %d, bytes %d), level %d/%d\n", 1108 info.curr_entry, info.num_entries, info.max_entries, 1109 info.bytes_avail, info.curr_level, info.max_depth); 1110 printf("\tmax lblk: %llu, max pblk: %llu\n", info.max_lblk, 1111 info.max_pblk); 1112 printf("\tmax_len: %u, max_uninit_len: %u\n", info.max_len, 1113 info.max_uninit_len); 1114} 1115 1116void do_goto_block(int argc, char **argv) 1117{ 1118 struct ext2fs_extent extent; 1119 errcode_t retval; 1120 int op = EXT2_EXTENT_NEXT_LEAF; 1121 blk_t blk; 1122 1123 if (check_fs_open(argv[0])) 1124 return; 1125 1126 if (!current_handle) { 1127 com_err(argv[0], 0, "Extent handle not open"); 1128 return; 1129 } 1130 1131 if (argc != 2) { 1132 fprintf(stderr, "%s block\n", argv[0]); 1133 return; 1134 } 1135 1136 if (strtoblk(argv[0], argv[1], &blk)) 1137 return; 1138 1139 retval = ext2fs_extent_goto(current_handle, (blk64_t) blk); 1140 if (retval) { 1141 com_err(argv[0], retval, "while trying to go to block %lu", 1142 blk); 1143 return; 1144 } 1145 1146 generic_goto_node(argv[0], EXT2_EXTENT_CURRENT); 1147} 1148#endif 1149 1150