extent.c revision 2d328bb76d2d63bdfdba923b54c28bd686bd8fec
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 */ 154extern void ext2fs_extent_free(ext2_extent_handle_t handle) 155{ 156 int i; 157 158 if (!handle) 159 return; 160 161 if (handle->inode) 162 ext2fs_free_mem(&handle->inode); 163 if (handle->path) { 164 for (i=1; i < handle->max_depth; i++) { 165 if (handle->path[i].buf) 166 ext2fs_free_mem(&handle->path[i].buf); 167 } 168 ext2fs_free_mem(&handle->path); 169 } 170 ext2fs_free_mem(&handle); 171} 172 173extern errcode_t ext2fs_extent_open(ext2_filsys fs, ext2_ino_t ino, 174 ext2_extent_handle_t *ret_handle) 175{ 176 struct ext2_extent_handle *handle; 177 errcode_t retval; 178 int isize = EXT2_INODE_SIZE(fs->super); 179 struct ext3_extent_header *eh; 180 181 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 182 183 if ((ino == 0) || (ino > fs->super->s_inodes_count)) 184 return EXT2_ET_BAD_INODE_NUM; 185 186 retval = ext2fs_get_mem(sizeof(struct ext2_extent_handle), &handle); 187 if (retval) 188 return retval; 189 memset(handle, 0, sizeof(struct ext2_extent_handle)); 190 191 retval = ext2fs_get_mem(isize, &handle->inode); 192 if (retval) 193 goto errout; 194 195 handle->ino = ino; 196 handle->fs = fs; 197 198 retval = ext2fs_read_inode_full(fs, ino, handle->inode, isize); 199 if (retval) 200 goto errout; 201 202 if (!(handle->inode->i_flags & EXT4_EXTENTS_FL)) 203 return EXT2_ET_INODE_NOT_EXTENT; 204 205 eh = (struct ext3_extent_header *) &handle->inode->i_block[0]; 206 207 retval = ext2fs_extent_header_verify(eh, sizeof(handle->inode->i_block)); 208 if (retval) 209 return (retval); 210 211 handle->max_depth = ext2fs_le16_to_cpu(eh->eh_depth); 212 handle->type = ext2fs_le16_to_cpu(eh->eh_magic); 213 214 retval = ext2fs_get_mem(((handle->max_depth+1) * 215 sizeof(struct extent_path)), 216 &handle->path); 217 memset(handle->path, 0, 218 (handle->max_depth+1) * sizeof(struct extent_path)); 219 handle->path[0].buf = (char *) handle->inode->i_block; 220 221 handle->path[0].left = handle->path[0].entries = 222 ext2fs_le16_to_cpu(eh->eh_entries); 223 handle->path[0].max_entries = ext2fs_le16_to_cpu(eh->eh_max); 224 handle->path[0].curr = 0; 225 handle->path[0].end_blk = 226 ((((__u64) handle->inode->i_size_high << 32) + 227 handle->inode->i_size + (fs->blocksize - 1)) 228 >> EXT2_BLOCK_SIZE_BITS(fs->super)); 229 handle->path[0].visit_num = 1; 230 handle->level = 0; 231 handle->magic = EXT2_ET_MAGIC_EXTENT_HANDLE; 232 233 *ret_handle = handle; 234 return 0; 235 236errout: 237 ext2fs_extent_free(handle); 238 return retval; 239} 240 241/* 242 * This function is responsible for (optionally) moving through the 243 * extent tree and then returning the current extent 244 */ 245errcode_t ext2fs_extent_get(ext2_extent_handle_t handle, 246 int flags, struct ext2fs_extent *extent) 247{ 248 struct extent_path *path, *newpath; 249 struct ext3_extent_header *eh; 250 struct ext3_extent_idx *ix = 0; 251 struct ext3_extent *ex; 252 errcode_t retval; 253 blk_t blk; 254 blk64_t end_blk; 255 int orig_op, op; 256 257 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 258 259 if (!handle->path) 260 return EXT2_ET_NO_CURRENT_NODE; 261 262 orig_op = op = flags & EXT2_EXTENT_MOVE_MASK; 263 264retry: 265 path = handle->path + handle->level; 266 if ((orig_op == EXT2_EXTENT_NEXT) || 267 (orig_op == EXT2_EXTENT_NEXT_LEAF)) { 268 if (handle->level < handle->max_depth) { 269 /* interior node */ 270 if (path->visit_num == 0) { 271 path->visit_num++; 272 op = EXT2_EXTENT_DOWN; 273 } else if (path->left > 0) 274 op = EXT2_EXTENT_NEXT_SIB; 275 else if (handle->level > 0) 276 op = EXT2_EXTENT_UP; 277 else 278 return EXT2_ET_EXTENT_NO_NEXT; 279 } else { 280 /* leaf node */ 281 if (path->left > 0) 282 op = EXT2_EXTENT_NEXT_SIB; 283 else if (handle->level > 0) 284 op = EXT2_EXTENT_UP; 285 else 286 return EXT2_ET_EXTENT_NO_NEXT; 287 } 288 if (op != EXT2_EXTENT_NEXT_SIB) { 289 dbg_printf("<<<< OP = %s\n", 290 (op == EXT2_EXTENT_DOWN) ? "down" : 291 ((op == EXT2_EXTENT_UP) ? "up" : "unknown")); 292 } 293 } 294 295 if ((orig_op == EXT2_EXTENT_PREV) || 296 (orig_op == EXT2_EXTENT_PREV_LEAF)) { 297 if (handle->level < handle->max_depth) { 298 /* interior node */ 299 if (path->visit_num > 0 ) { 300 /* path->visit_num = 0; */ 301 op = EXT2_EXTENT_DOWN_AND_LAST; 302 } else if (path->left < path->entries-1) 303 op = EXT2_EXTENT_PREV_SIB; 304 else if (handle->level > 0) 305 op = EXT2_EXTENT_UP; 306 else 307 return EXT2_ET_EXTENT_NO_PREV; 308 } else { 309 /* leaf node */ 310 if (path->left < path->entries-1) 311 op = EXT2_EXTENT_PREV_SIB; 312 else if (handle->level > 0) 313 op = EXT2_EXTENT_UP; 314 else 315 return EXT2_ET_EXTENT_NO_PREV; 316 } 317 if (op != EXT2_EXTENT_PREV_SIB) { 318 dbg_printf("<<<< OP = %s\n", 319 (op == EXT2_EXTENT_DOWN_AND_LAST) ? "down/last" : 320 ((op == EXT2_EXTENT_UP) ? "up" : "unknown")); 321 } 322 } 323 324 if (orig_op == EXT2_EXTENT_LAST_LEAF) { 325 if ((handle->level < handle->max_depth) && 326 (path->left == 0)) 327 op = EXT2_EXTENT_DOWN; 328 else 329 op = EXT2_EXTENT_LAST_SIB; 330 dbg_printf("<<<< OP = %s\n", 331 (op == EXT2_EXTENT_DOWN) ? "down" : "last_sib"); 332 } 333 334 switch (op) { 335 case EXT2_EXTENT_CURRENT: 336 ix = path->curr; 337 break; 338 case EXT2_EXTENT_ROOT: 339 handle->level = 0; 340 path = handle->path + handle->level; 341 case EXT2_EXTENT_FIRST_SIB: 342 path->left = path->entries; 343 path->curr = 0; 344 case EXT2_EXTENT_NEXT_SIB: 345 if (path->left <= 0) 346 return EXT2_ET_EXTENT_NO_NEXT; 347 if (path->curr) { 348 ix = path->curr; 349 ix++; 350 } else { 351 eh = (struct ext3_extent_header *) path->buf; 352 ix = EXT_FIRST_INDEX(eh); 353 } 354 path->left--; 355 path->curr = ix; 356 path->visit_num = 0; 357 break; 358 case EXT2_EXTENT_PREV_SIB: 359 if (!path->curr || 360 path->left+1 >= path->entries) 361 return EXT2_ET_EXTENT_NO_PREV; 362 ix = path->curr; 363 ix--; 364 path->curr = ix; 365 path->left++; 366 if (handle->level < handle->max_depth) 367 path->visit_num = 1; 368 break; 369 case EXT2_EXTENT_LAST_SIB: 370 eh = (struct ext3_extent_header *) path->buf; 371 path->curr = EXT_LAST_EXTENT(eh); 372 ix = path->curr; 373 path->left = 0; 374 path->visit_num = 0; 375 break; 376 case EXT2_EXTENT_UP: 377 if (handle->level <= 0) 378 return EXT2_ET_EXTENT_NO_UP; 379 handle->level--; 380 path--; 381 ix = path->curr; 382 if ((orig_op == EXT2_EXTENT_PREV) || 383 (orig_op == EXT2_EXTENT_PREV_LEAF)) 384 path->visit_num = 0; 385 break; 386 case EXT2_EXTENT_DOWN: 387 case EXT2_EXTENT_DOWN_AND_LAST: 388 if (!path->curr ||(handle->level >= handle->max_depth)) 389 return EXT2_ET_EXTENT_NO_DOWN; 390 391 ix = path->curr; 392 newpath = path + 1; 393 if (!newpath->buf) { 394 retval = ext2fs_get_mem(handle->fs->blocksize, 395 &newpath->buf); 396 if (retval) 397 return retval; 398 } 399 blk = ext2fs_le32_to_cpu(ix->ei_leaf) + 400 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32); 401 if ((handle->fs->flags & EXT2_FLAG_IMAGE_FILE) && 402 (handle->fs->io != handle->fs->image_io)) 403 memset(newpath->buf, 0, handle->fs->blocksize); 404 else { 405 retval = io_channel_read_blk(handle->fs->io, 406 blk, 1, newpath->buf); 407 if (retval) 408 return retval; 409 } 410 handle->level++; 411 412 eh = (struct ext3_extent_header *) newpath->buf; 413 414 retval = ext2fs_extent_header_verify(eh, handle->fs->blocksize); 415 if (retval) 416 return retval; 417 418 newpath->left = newpath->entries = 419 ext2fs_le16_to_cpu(eh->eh_entries); 420 newpath->max_entries = ext2fs_le16_to_cpu(eh->eh_max); 421 422 if (path->left > 0) { 423 ix++; 424 newpath->end_blk = ext2fs_le32_to_cpu(ix->ei_block); 425 } else 426 newpath->end_blk = path->end_blk; 427 428 path = newpath; 429 if (op == EXT2_EXTENT_DOWN) { 430 ix = EXT_FIRST_INDEX((struct ext3_extent_header *) eh); 431 path->curr = ix; 432 path->left = path->entries - 1; 433 path->visit_num = 0; 434 } else { 435 ix = EXT_LAST_INDEX((struct ext3_extent_header *) eh); 436 path->curr = ix; 437 path->left = 0; 438 if (handle->level < handle->max_depth) 439 path->visit_num = 1; 440 } 441 442 dbg_printf("Down to level %d/%d, end_blk=%llu\n", 443 handle->level, handle->max_depth, 444 path->end_blk); 445 446 break; 447 default: 448 return EXT2_ET_OP_NOT_SUPPORTED; 449 } 450 451 if (!ix) 452 return EXT2_ET_NO_CURRENT_NODE; 453 454 extent->e_flags = 0; 455 dbg_printf("(Left %d)\n", path->left); 456 457 if (handle->level == handle->max_depth) { 458 ex = (struct ext3_extent *) ix; 459 460 extent->e_pblk = ext2fs_le32_to_cpu(ex->ee_start) + 461 ((__u64) ext2fs_le16_to_cpu(ex->ee_start_hi) << 32); 462 extent->e_lblk = ext2fs_le32_to_cpu(ex->ee_block); 463 extent->e_len = ext2fs_le16_to_cpu(ex->ee_len); 464 extent->e_flags = EXT2_EXTENT_FLAGS_LEAF; 465 if (extent->e_len > EXT_INIT_MAX_LEN) { 466 extent->e_len -= EXT_INIT_MAX_LEN; 467 extent->e_flags = EXT2_EXTENT_FLAGS_UNINIT; 468 } 469 } else { 470 extent->e_pblk = ext2fs_le32_to_cpu(ix->ei_leaf) + 471 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32); 472 extent->e_lblk = ext2fs_le32_to_cpu(ix->ei_block); 473 if (path->left > 0) { 474 ix++; 475 end_blk = ext2fs_le32_to_cpu(ix->ei_block); 476 } else 477 end_blk = path->end_blk; 478 479 extent->e_len = end_blk - extent->e_lblk; 480 } 481 if (path->visit_num) 482 extent->e_flags |= EXT2_EXTENT_FLAGS_SECOND_VISIT; 483 484 if (((orig_op == EXT2_EXTENT_NEXT_LEAF) || 485 (orig_op == EXT2_EXTENT_PREV_LEAF)) && 486 (handle->level != handle->max_depth)) 487 goto retry; 488 489 if ((orig_op == EXT2_EXTENT_LAST_LEAF) && 490 ((handle->level != handle->max_depth) || 491 (path->left != 0))) 492 goto retry; 493 494 return 0; 495} 496 497static errcode_t update_path(ext2_extent_handle_t handle) 498{ 499 blk64_t blk; 500 errcode_t retval; 501 struct ext3_extent_idx *ix; 502 503 if (handle->level == 0) { 504 retval = ext2fs_write_inode_full(handle->fs, handle->ino, 505 handle->inode, EXT2_INODE_SIZE(handle->fs->super)); 506 } else { 507 ix = handle->path[handle->level - 1].curr; 508 blk = ext2fs_le32_to_cpu(ix->ei_leaf) + 509 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32); 510 511 retval = io_channel_write_blk(handle->fs->io, 512 blk, 1, handle->path[handle->level].buf); 513 } 514 return retval; 515} 516 517#if 0 518errcode_t ext2fs_extent_save_path(ext2_extent_handle_t handle, 519 ext2_extent_path_t *ret_path) 520{ 521 ext2_extent_path_t save_path; 522 struct ext2fs_extent extent; 523 struct ext2_extent_info info; 524 errcode_t retval; 525 526 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent); 527 if (retval) 528 return retval; 529 530 retval = ext2fs_extent_get_info(handle, &info); 531 if (retval) 532 return retval; 533 534 retval = ext2fs_get_mem(sizeof(struct ext2_extent_path), &save_path); 535 if (retval) 536 return retval; 537 memset(save_path, 0, sizeof(struct ext2_extent_path)); 538 539 save_path->magic = EXT2_ET_MAGIC_EXTENT_PATH; 540 save_path->leaf_height = info.max_depth - info.curr_level - 1; 541 save_path->lblk = extent.e_lblk; 542 543 *ret_path = save_path; 544 return 0; 545} 546 547errcode_t ext2fs_extent_free_path(ext2_extent_path_t path) 548{ 549 EXT2_CHECK_MAGIC(path, EXT2_ET_MAGIC_EXTENT_PATH); 550 551 ext2fs_free_mem(&path); 552 return 0; 553} 554#endif 555 556static errcode_t extent_goto(ext2_extent_handle_t handle, 557 int leaf_level, blk64_t blk) 558{ 559 struct ext2fs_extent extent; 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, 621 int flags EXT2FS_ATTR((unused)), 622 struct ext2fs_extent *extent) 623{ 624 struct extent_path *path; 625 struct ext3_extent_idx *ix; 626 struct ext3_extent *ex; 627 628 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 629 630 if (!(handle->fs->flags & EXT2_FLAG_RW)) 631 return EXT2_ET_RO_FILSYS; 632 633 if (!handle->path) 634 return EXT2_ET_NO_CURRENT_NODE; 635 636 path = handle->path + handle->level; 637 if (!path->curr) 638 return EXT2_ET_NO_CURRENT_NODE; 639 640 if (handle->level == handle->max_depth) { 641 ex = path->curr; 642 643 ex->ee_block = ext2fs_cpu_to_le32(extent->e_lblk); 644 ex->ee_start = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF); 645 ex->ee_start_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32); 646 ex->ee_len = ext2fs_cpu_to_le16(extent->e_len); 647 } else { 648 ix = path->curr; 649 650 ix->ei_leaf = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF); 651 ix->ei_leaf_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32); 652 ix->ei_block = ext2fs_cpu_to_le32(extent->e_lblk); 653 ix->ei_unused = 0; 654 } 655 update_path(handle); 656 return 0; 657} 658 659errcode_t ext2fs_extent_insert(ext2_extent_handle_t handle, int flags, 660 struct ext2fs_extent *extent) 661{ 662 struct extent_path *path; 663 struct ext3_extent_idx *ix; 664 struct ext3_extent_header *eh; 665 errcode_t retval; 666 667 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 668 669 if (!(handle->fs->flags & EXT2_FLAG_RW)) 670 return EXT2_ET_RO_FILSYS; 671 672 if (!handle->path) 673 return EXT2_ET_NO_CURRENT_NODE; 674 675 path = handle->path + handle->level; 676 677 if (path->entries >= path->max_entries) 678 return EXT2_ET_CANT_INSERT_EXTENT; 679 680 eh = (struct ext3_extent_header *) path->buf; 681 if (path->curr) { 682 ix = path->curr; 683 if (flags & EXT2_EXTENT_INSERT_AFTER) { 684 ix++; 685 path->left--; 686 } 687 } else 688 ix = EXT_FIRST_INDEX(eh); 689 690 path->curr = ix; 691 692 if (path->left > 0) 693 memmove(ix + 1, ix, 694 (path->left+1) * sizeof(struct ext3_extent_idx)); 695 path->left++; 696 path->entries++; 697 698 eh = (struct ext3_extent_header *) path->buf; 699 eh->eh_entries = ext2fs_cpu_to_le16(path->entries); 700 701 retval = ext2fs_extent_replace(handle, 0, extent); 702 if (retval) 703 goto errout; 704 705 retval = update_path(handle); 706 if (retval) 707 goto errout; 708 709 return 0; 710 711errout: 712 ext2fs_extent_delete(handle, 0); 713 return retval; 714} 715 716errcode_t ext2fs_extent_delete(ext2_extent_handle_t handle, 717 int flags EXT2FS_ATTR((unused))) 718{ 719 struct extent_path *path; 720 char *cp; 721 struct ext3_extent_header *eh; 722 errcode_t retval; 723 724 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE); 725 726 if (!(handle->fs->flags & EXT2_FLAG_RW)) 727 return EXT2_ET_RO_FILSYS; 728 729 if (!handle->path) 730 return EXT2_ET_NO_CURRENT_NODE; 731 732 path = handle->path + handle->level; 733 if (!path->curr) 734 return EXT2_ET_NO_CURRENT_NODE; 735 736 cp = path->curr; 737 738 if (path->left) { 739 memmove(cp, cp + sizeof(struct ext3_extent_idx), 740 path->left * sizeof(struct ext3_extent_idx)); 741 path->left--; 742 } else { 743 struct ext3_extent_idx *ix = path->curr; 744 ix--; 745 path->curr = ix; 746 } 747 path->entries--; 748 if (path->entries == 0) 749 path->curr = 0; 750 751 eh = (struct ext3_extent_header *) path->buf; 752 eh->eh_entries = ext2fs_cpu_to_le16(path->entries); 753 754 retval = update_path(handle); 755 756 return retval; 757} 758 759errcode_t ext2fs_extent_get_info(ext2_extent_handle_t handle, 760 struct ext2_extent_info *info) 761{ 762 struct extent_path *path; 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 */ 798const char *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