1/* 2 * lcnalloc.c - Cluster (de)allocation code. Part of the Linux-NTFS project. 3 * 4 * Copyright (c) 2004-2005 Anton Altaparmakov 5 * 6 * This program/include file is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as published 8 * by the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program/include file is distributed in the hope that it will be 12 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 13 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program (in the main directory of the Linux-NTFS 18 * distribution in the file COPYING); if not, write to the Free Software 19 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 22#ifdef NTFS_RW 23 24#include <linux/pagemap.h> 25 26#include "lcnalloc.h" 27#include "debug.h" 28#include "bitmap.h" 29#include "inode.h" 30#include "volume.h" 31#include "attrib.h" 32#include "malloc.h" 33#include "aops.h" 34#include "ntfs.h" 35 36/** 37 * ntfs_cluster_free_from_rl_nolock - free clusters from runlist 38 * @vol: mounted ntfs volume on which to free the clusters 39 * @rl: runlist describing the clusters to free 40 * 41 * Free all the clusters described by the runlist @rl on the volume @vol. In 42 * the case of an error being returned, at least some of the clusters were not 43 * freed. 44 * 45 * Return 0 on success and -errno on error. 46 * 47 * Locking: - The volume lcn bitmap must be locked for writing on entry and is 48 * left locked on return. 49 */ 50int ntfs_cluster_free_from_rl_nolock(ntfs_volume *vol, 51 const runlist_element *rl) 52{ 53 struct inode *lcnbmp_vi = vol->lcnbmp_ino; 54 int ret = 0; 55 56 ntfs_debug("Entering."); 57 if (!rl) 58 return 0; 59 for (; rl->length; rl++) { 60 int err; 61 62 if (rl->lcn < 0) 63 continue; 64 err = ntfs_bitmap_clear_run(lcnbmp_vi, rl->lcn, rl->length); 65 if (unlikely(err && (!ret || ret == -ENOMEM) && ret != err)) 66 ret = err; 67 } 68 ntfs_debug("Done."); 69 return ret; 70} 71 72runlist_element *ntfs_cluster_alloc(ntfs_volume *vol, const VCN start_vcn, 73 const s64 count, const LCN start_lcn, 74 const NTFS_CLUSTER_ALLOCATION_ZONES zone, 75 const bool is_extension) 76{ 77 LCN zone_start, zone_end, bmp_pos, bmp_initial_pos, last_read_pos, lcn; 78 LCN prev_lcn = 0, prev_run_len = 0, mft_zone_size; 79 s64 clusters; 80 loff_t i_size; 81 struct inode *lcnbmp_vi; 82 runlist_element *rl = NULL; 83 struct address_space *mapping; 84 struct page *page = NULL; 85 u8 *buf, *byte; 86 int err = 0, rlpos, rlsize, buf_size; 87 u8 pass, done_zones, search_zone, need_writeback = 0, bit; 88 89 ntfs_debug("Entering for start_vcn 0x%llx, count 0x%llx, start_lcn " 90 "0x%llx, zone %s_ZONE.", (unsigned long long)start_vcn, 91 (unsigned long long)count, 92 (unsigned long long)start_lcn, 93 zone == MFT_ZONE ? "MFT" : "DATA"); 94 BUG_ON(!vol); 95 lcnbmp_vi = vol->lcnbmp_ino; 96 BUG_ON(!lcnbmp_vi); 97 BUG_ON(start_vcn < 0); 98 BUG_ON(count < 0); 99 BUG_ON(start_lcn < -1); 100 BUG_ON(zone < FIRST_ZONE); 101 BUG_ON(zone > LAST_ZONE); 102 103 /* Return NULL if @count is zero. */ 104 if (!count) 105 return NULL; 106 /* Take the lcnbmp lock for writing. */ 107 down_write(&vol->lcnbmp_lock); 108 /* 109 * If no specific @start_lcn was requested, use the current data zone 110 * position, otherwise use the requested @start_lcn but make sure it 111 * lies outside the mft zone. Also set done_zones to 0 (no zones done) 112 * and pass depending on whether we are starting inside a zone (1) or 113 * at the beginning of a zone (2). If requesting from the MFT_ZONE, 114 * we either start at the current position within the mft zone or at 115 * the specified position. If the latter is out of bounds then we start 116 * at the beginning of the MFT_ZONE. 117 */ 118 done_zones = 0; 119 pass = 1; 120 /* 121 * zone_start and zone_end are the current search range. search_zone 122 * is 1 for mft zone, 2 for data zone 1 (end of mft zone till end of 123 * volume) and 4 for data zone 2 (start of volume till start of mft 124 * zone). 125 */ 126 zone_start = start_lcn; 127 if (zone_start < 0) { 128 if (zone == DATA_ZONE) 129 zone_start = vol->data1_zone_pos; 130 else 131 zone_start = vol->mft_zone_pos; 132 if (!zone_start) { 133 /* 134 * Zone starts at beginning of volume which means a 135 * single pass is sufficient. 136 */ 137 pass = 2; 138 } 139 } else if (zone == DATA_ZONE && zone_start >= vol->mft_zone_start && 140 zone_start < vol->mft_zone_end) { 141 zone_start = vol->mft_zone_end; 142 /* 143 * Starting at beginning of data1_zone which means a single 144 * pass in this zone is sufficient. 145 */ 146 pass = 2; 147 } else if (zone == MFT_ZONE && (zone_start < vol->mft_zone_start || 148 zone_start >= vol->mft_zone_end)) { 149 zone_start = vol->mft_lcn; 150 if (!vol->mft_zone_end) 151 zone_start = 0; 152 /* 153 * Starting at beginning of volume which means a single pass 154 * is sufficient. 155 */ 156 pass = 2; 157 } 158 if (zone == MFT_ZONE) { 159 zone_end = vol->mft_zone_end; 160 search_zone = 1; 161 } else /* if (zone == DATA_ZONE) */ { 162 /* Skip searching the mft zone. */ 163 done_zones |= 1; 164 if (zone_start >= vol->mft_zone_end) { 165 zone_end = vol->nr_clusters; 166 search_zone = 2; 167 } else { 168 zone_end = vol->mft_zone_start; 169 search_zone = 4; 170 } 171 } 172 /* 173 * bmp_pos is the current bit position inside the bitmap. We use 174 * bmp_initial_pos to determine whether or not to do a zone switch. 175 */ 176 bmp_pos = bmp_initial_pos = zone_start; 177 178 /* Loop until all clusters are allocated, i.e. clusters == 0. */ 179 clusters = count; 180 rlpos = rlsize = 0; 181 mapping = lcnbmp_vi->i_mapping; 182 i_size = i_size_read(lcnbmp_vi); 183 while (1) { 184 ntfs_debug("Start of outer while loop: done_zones 0x%x, " 185 "search_zone %i, pass %i, zone_start 0x%llx, " 186 "zone_end 0x%llx, bmp_initial_pos 0x%llx, " 187 "bmp_pos 0x%llx, rlpos %i, rlsize %i.", 188 done_zones, search_zone, pass, 189 (unsigned long long)zone_start, 190 (unsigned long long)zone_end, 191 (unsigned long long)bmp_initial_pos, 192 (unsigned long long)bmp_pos, rlpos, rlsize); 193 /* Loop until we run out of free clusters. */ 194 last_read_pos = bmp_pos >> 3; 195 ntfs_debug("last_read_pos 0x%llx.", 196 (unsigned long long)last_read_pos); 197 if (last_read_pos > i_size) { 198 ntfs_debug("End of attribute reached. " 199 "Skipping to zone_pass_done."); 200 goto zone_pass_done; 201 } 202 if (likely(page)) { 203 if (need_writeback) { 204 ntfs_debug("Marking page dirty."); 205 flush_dcache_page(page); 206 set_page_dirty(page); 207 need_writeback = 0; 208 } 209 ntfs_unmap_page(page); 210 } 211 page = ntfs_map_page(mapping, last_read_pos >> 212 PAGE_CACHE_SHIFT); 213 if (IS_ERR(page)) { 214 err = PTR_ERR(page); 215 ntfs_error(vol->sb, "Failed to map page."); 216 goto out; 217 } 218 buf_size = last_read_pos & ~PAGE_CACHE_MASK; 219 buf = page_address(page) + buf_size; 220 buf_size = PAGE_CACHE_SIZE - buf_size; 221 if (unlikely(last_read_pos + buf_size > i_size)) 222 buf_size = i_size - last_read_pos; 223 buf_size <<= 3; 224 lcn = bmp_pos & 7; 225 bmp_pos &= ~(LCN)7; 226 ntfs_debug("Before inner while loop: buf_size %i, lcn 0x%llx, " 227 "bmp_pos 0x%llx, need_writeback %i.", buf_size, 228 (unsigned long long)lcn, 229 (unsigned long long)bmp_pos, need_writeback); 230 while (lcn < buf_size && lcn + bmp_pos < zone_end) { 231 byte = buf + (lcn >> 3); 232 ntfs_debug("In inner while loop: buf_size %i, " 233 "lcn 0x%llx, bmp_pos 0x%llx, " 234 "need_writeback %i, byte ofs 0x%x, " 235 "*byte 0x%x.", buf_size, 236 (unsigned long long)lcn, 237 (unsigned long long)bmp_pos, 238 need_writeback, 239 (unsigned int)(lcn >> 3), 240 (unsigned int)*byte); 241 /* Skip full bytes. */ 242 if (*byte == 0xff) { 243 lcn = (lcn + 8) & ~(LCN)7; 244 ntfs_debug("Continuing while loop 1."); 245 continue; 246 } 247 bit = 1 << (lcn & 7); 248 ntfs_debug("bit 0x%x.", bit); 249 /* If the bit is already set, go onto the next one. */ 250 if (*byte & bit) { 251 lcn++; 252 ntfs_debug("Continuing while loop 2."); 253 continue; 254 } 255 /* 256 * Allocate more memory if needed, including space for 257 * the terminator element. 258 * ntfs_malloc_nofs() operates on whole pages only. 259 */ 260 if ((rlpos + 2) * sizeof(*rl) > rlsize) { 261 runlist_element *rl2; 262 263 ntfs_debug("Reallocating memory."); 264 if (!rl) 265 ntfs_debug("First free bit is at LCN " 266 "0x%llx.", 267 (unsigned long long) 268 (lcn + bmp_pos)); 269 rl2 = ntfs_malloc_nofs(rlsize + (int)PAGE_SIZE); 270 if (unlikely(!rl2)) { 271 err = -ENOMEM; 272 ntfs_error(vol->sb, "Failed to " 273 "allocate memory."); 274 goto out; 275 } 276 memcpy(rl2, rl, rlsize); 277 ntfs_free(rl); 278 rl = rl2; 279 rlsize += PAGE_SIZE; 280 ntfs_debug("Reallocated memory, rlsize 0x%x.", 281 rlsize); 282 } 283 /* Allocate the bitmap bit. */ 284 *byte |= bit; 285 /* We need to write this bitmap page to disk. */ 286 need_writeback = 1; 287 ntfs_debug("*byte 0x%x, need_writeback is set.", 288 (unsigned int)*byte); 289 /* 290 * Coalesce with previous run if adjacent LCNs. 291 * Otherwise, append a new run. 292 */ 293 ntfs_debug("Adding run (lcn 0x%llx, len 0x%llx), " 294 "prev_lcn 0x%llx, lcn 0x%llx, " 295 "bmp_pos 0x%llx, prev_run_len 0x%llx, " 296 "rlpos %i.", 297 (unsigned long long)(lcn + bmp_pos), 298 1ULL, (unsigned long long)prev_lcn, 299 (unsigned long long)lcn, 300 (unsigned long long)bmp_pos, 301 (unsigned long long)prev_run_len, 302 rlpos); 303 if (prev_lcn == lcn + bmp_pos - prev_run_len && rlpos) { 304 ntfs_debug("Coalescing to run (lcn 0x%llx, " 305 "len 0x%llx).", 306 (unsigned long long) 307 rl[rlpos - 1].lcn, 308 (unsigned long long) 309 rl[rlpos - 1].length); 310 rl[rlpos - 1].length = ++prev_run_len; 311 ntfs_debug("Run now (lcn 0x%llx, len 0x%llx), " 312 "prev_run_len 0x%llx.", 313 (unsigned long long) 314 rl[rlpos - 1].lcn, 315 (unsigned long long) 316 rl[rlpos - 1].length, 317 (unsigned long long) 318 prev_run_len); 319 } else { 320 if (likely(rlpos)) { 321 ntfs_debug("Adding new run, (previous " 322 "run lcn 0x%llx, " 323 "len 0x%llx).", 324 (unsigned long long) 325 rl[rlpos - 1].lcn, 326 (unsigned long long) 327 rl[rlpos - 1].length); 328 rl[rlpos].vcn = rl[rlpos - 1].vcn + 329 prev_run_len; 330 } else { 331 ntfs_debug("Adding new run, is first " 332 "run."); 333 rl[rlpos].vcn = start_vcn; 334 } 335 rl[rlpos].lcn = prev_lcn = lcn + bmp_pos; 336 rl[rlpos].length = prev_run_len = 1; 337 rlpos++; 338 } 339 /* Done? */ 340 if (!--clusters) { 341 LCN tc; 342 /* 343 * Update the current zone position. Positions 344 * of already scanned zones have been updated 345 * during the respective zone switches. 346 */ 347 tc = lcn + bmp_pos + 1; 348 ntfs_debug("Done. Updating current zone " 349 "position, tc 0x%llx, " 350 "search_zone %i.", 351 (unsigned long long)tc, 352 search_zone); 353 switch (search_zone) { 354 case 1: 355 ntfs_debug("Before checks, " 356 "vol->mft_zone_pos " 357 "0x%llx.", 358 (unsigned long long) 359 vol->mft_zone_pos); 360 if (tc >= vol->mft_zone_end) { 361 vol->mft_zone_pos = 362 vol->mft_lcn; 363 if (!vol->mft_zone_end) 364 vol->mft_zone_pos = 0; 365 } else if ((bmp_initial_pos >= 366 vol->mft_zone_pos || 367 tc > vol->mft_zone_pos) 368 && tc >= vol->mft_lcn) 369 vol->mft_zone_pos = tc; 370 ntfs_debug("After checks, " 371 "vol->mft_zone_pos " 372 "0x%llx.", 373 (unsigned long long) 374 vol->mft_zone_pos); 375 break; 376 case 2: 377 ntfs_debug("Before checks, " 378 "vol->data1_zone_pos " 379 "0x%llx.", 380 (unsigned long long) 381 vol->data1_zone_pos); 382 if (tc >= vol->nr_clusters) 383 vol->data1_zone_pos = 384 vol->mft_zone_end; 385 else if ((bmp_initial_pos >= 386 vol->data1_zone_pos || 387 tc > vol->data1_zone_pos) 388 && tc >= vol->mft_zone_end) 389 vol->data1_zone_pos = tc; 390 ntfs_debug("After checks, " 391 "vol->data1_zone_pos " 392 "0x%llx.", 393 (unsigned long long) 394 vol->data1_zone_pos); 395 break; 396 case 4: 397 ntfs_debug("Before checks, " 398 "vol->data2_zone_pos " 399 "0x%llx.", 400 (unsigned long long) 401 vol->data2_zone_pos); 402 if (tc >= vol->mft_zone_start) 403 vol->data2_zone_pos = 0; 404 else if (bmp_initial_pos >= 405 vol->data2_zone_pos || 406 tc > vol->data2_zone_pos) 407 vol->data2_zone_pos = tc; 408 ntfs_debug("After checks, " 409 "vol->data2_zone_pos " 410 "0x%llx.", 411 (unsigned long long) 412 vol->data2_zone_pos); 413 break; 414 default: 415 BUG(); 416 } 417 ntfs_debug("Finished. Going to out."); 418 goto out; 419 } 420 lcn++; 421 } 422 bmp_pos += buf_size; 423 ntfs_debug("After inner while loop: buf_size 0x%x, lcn " 424 "0x%llx, bmp_pos 0x%llx, need_writeback %i.", 425 buf_size, (unsigned long long)lcn, 426 (unsigned long long)bmp_pos, need_writeback); 427 if (bmp_pos < zone_end) { 428 ntfs_debug("Continuing outer while loop, " 429 "bmp_pos 0x%llx, zone_end 0x%llx.", 430 (unsigned long long)bmp_pos, 431 (unsigned long long)zone_end); 432 continue; 433 } 434zone_pass_done: /* Finished with the current zone pass. */ 435 ntfs_debug("At zone_pass_done, pass %i.", pass); 436 if (pass == 1) { 437 /* 438 * Now do pass 2, scanning the first part of the zone 439 * we omitted in pass 1. 440 */ 441 pass = 2; 442 zone_end = zone_start; 443 switch (search_zone) { 444 case 1: /* mft_zone */ 445 zone_start = vol->mft_zone_start; 446 break; 447 case 2: /* data1_zone */ 448 zone_start = vol->mft_zone_end; 449 break; 450 case 4: /* data2_zone */ 451 zone_start = 0; 452 break; 453 default: 454 BUG(); 455 } 456 /* Sanity check. */ 457 if (zone_end < zone_start) 458 zone_end = zone_start; 459 bmp_pos = zone_start; 460 ntfs_debug("Continuing outer while loop, pass 2, " 461 "zone_start 0x%llx, zone_end 0x%llx, " 462 "bmp_pos 0x%llx.", 463 (unsigned long long)zone_start, 464 (unsigned long long)zone_end, 465 (unsigned long long)bmp_pos); 466 continue; 467 } /* pass == 2 */ 468done_zones_check: 469 ntfs_debug("At done_zones_check, search_zone %i, done_zones " 470 "before 0x%x, done_zones after 0x%x.", 471 search_zone, done_zones, 472 done_zones | search_zone); 473 done_zones |= search_zone; 474 if (done_zones < 7) { 475 ntfs_debug("Switching zone."); 476 /* Now switch to the next zone we haven't done yet. */ 477 pass = 1; 478 switch (search_zone) { 479 case 1: 480 ntfs_debug("Switching from mft zone to data1 " 481 "zone."); 482 /* Update mft zone position. */ 483 if (rlpos) { 484 LCN tc; 485 486 ntfs_debug("Before checks, " 487 "vol->mft_zone_pos " 488 "0x%llx.", 489 (unsigned long long) 490 vol->mft_zone_pos); 491 tc = rl[rlpos - 1].lcn + 492 rl[rlpos - 1].length; 493 if (tc >= vol->mft_zone_end) { 494 vol->mft_zone_pos = 495 vol->mft_lcn; 496 if (!vol->mft_zone_end) 497 vol->mft_zone_pos = 0; 498 } else if ((bmp_initial_pos >= 499 vol->mft_zone_pos || 500 tc > vol->mft_zone_pos) 501 && tc >= vol->mft_lcn) 502 vol->mft_zone_pos = tc; 503 ntfs_debug("After checks, " 504 "vol->mft_zone_pos " 505 "0x%llx.", 506 (unsigned long long) 507 vol->mft_zone_pos); 508 } 509 /* Switch from mft zone to data1 zone. */ 510switch_to_data1_zone: search_zone = 2; 511 zone_start = bmp_initial_pos = 512 vol->data1_zone_pos; 513 zone_end = vol->nr_clusters; 514 if (zone_start == vol->mft_zone_end) 515 pass = 2; 516 if (zone_start >= zone_end) { 517 vol->data1_zone_pos = zone_start = 518 vol->mft_zone_end; 519 pass = 2; 520 } 521 break; 522 case 2: 523 ntfs_debug("Switching from data1 zone to " 524 "data2 zone."); 525 /* Update data1 zone position. */ 526 if (rlpos) { 527 LCN tc; 528 529 ntfs_debug("Before checks, " 530 "vol->data1_zone_pos " 531 "0x%llx.", 532 (unsigned long long) 533 vol->data1_zone_pos); 534 tc = rl[rlpos - 1].lcn + 535 rl[rlpos - 1].length; 536 if (tc >= vol->nr_clusters) 537 vol->data1_zone_pos = 538 vol->mft_zone_end; 539 else if ((bmp_initial_pos >= 540 vol->data1_zone_pos || 541 tc > vol->data1_zone_pos) 542 && tc >= vol->mft_zone_end) 543 vol->data1_zone_pos = tc; 544 ntfs_debug("After checks, " 545 "vol->data1_zone_pos " 546 "0x%llx.", 547 (unsigned long long) 548 vol->data1_zone_pos); 549 } 550 /* Switch from data1 zone to data2 zone. */ 551 search_zone = 4; 552 zone_start = bmp_initial_pos = 553 vol->data2_zone_pos; 554 zone_end = vol->mft_zone_start; 555 if (!zone_start) 556 pass = 2; 557 if (zone_start >= zone_end) { 558 vol->data2_zone_pos = zone_start = 559 bmp_initial_pos = 0; 560 pass = 2; 561 } 562 break; 563 case 4: 564 ntfs_debug("Switching from data2 zone to " 565 "data1 zone."); 566 /* Update data2 zone position. */ 567 if (rlpos) { 568 LCN tc; 569 570 ntfs_debug("Before checks, " 571 "vol->data2_zone_pos " 572 "0x%llx.", 573 (unsigned long long) 574 vol->data2_zone_pos); 575 tc = rl[rlpos - 1].lcn + 576 rl[rlpos - 1].length; 577 if (tc >= vol->mft_zone_start) 578 vol->data2_zone_pos = 0; 579 else if (bmp_initial_pos >= 580 vol->data2_zone_pos || 581 tc > vol->data2_zone_pos) 582 vol->data2_zone_pos = tc; 583 ntfs_debug("After checks, " 584 "vol->data2_zone_pos " 585 "0x%llx.", 586 (unsigned long long) 587 vol->data2_zone_pos); 588 } 589 /* Switch from data2 zone to data1 zone. */ 590 goto switch_to_data1_zone; 591 default: 592 BUG(); 593 } 594 ntfs_debug("After zone switch, search_zone %i, " 595 "pass %i, bmp_initial_pos 0x%llx, " 596 "zone_start 0x%llx, zone_end 0x%llx.", 597 search_zone, pass, 598 (unsigned long long)bmp_initial_pos, 599 (unsigned long long)zone_start, 600 (unsigned long long)zone_end); 601 bmp_pos = zone_start; 602 if (zone_start == zone_end) { 603 ntfs_debug("Empty zone, going to " 604 "done_zones_check."); 605 /* Empty zone. Don't bother searching it. */ 606 goto done_zones_check; 607 } 608 ntfs_debug("Continuing outer while loop."); 609 continue; 610 } /* done_zones == 7 */ 611 ntfs_debug("All zones are finished."); 612 /* 613 * All zones are finished! If DATA_ZONE, shrink mft zone. If 614 * MFT_ZONE, we have really run out of space. 615 */ 616 mft_zone_size = vol->mft_zone_end - vol->mft_zone_start; 617 ntfs_debug("vol->mft_zone_start 0x%llx, vol->mft_zone_end " 618 "0x%llx, mft_zone_size 0x%llx.", 619 (unsigned long long)vol->mft_zone_start, 620 (unsigned long long)vol->mft_zone_end, 621 (unsigned long long)mft_zone_size); 622 if (zone == MFT_ZONE || mft_zone_size <= 0) { 623 ntfs_debug("No free clusters left, going to out."); 624 /* Really no more space left on device. */ 625 err = -ENOSPC; 626 goto out; 627 } /* zone == DATA_ZONE && mft_zone_size > 0 */ 628 ntfs_debug("Shrinking mft zone."); 629 zone_end = vol->mft_zone_end; 630 mft_zone_size >>= 1; 631 if (mft_zone_size > 0) 632 vol->mft_zone_end = vol->mft_zone_start + mft_zone_size; 633 else /* mft zone and data2 zone no longer exist. */ 634 vol->data2_zone_pos = vol->mft_zone_start = 635 vol->mft_zone_end = 0; 636 if (vol->mft_zone_pos >= vol->mft_zone_end) { 637 vol->mft_zone_pos = vol->mft_lcn; 638 if (!vol->mft_zone_end) 639 vol->mft_zone_pos = 0; 640 } 641 bmp_pos = zone_start = bmp_initial_pos = 642 vol->data1_zone_pos = vol->mft_zone_end; 643 search_zone = 2; 644 pass = 2; 645 done_zones &= ~2; 646 ntfs_debug("After shrinking mft zone, mft_zone_size 0x%llx, " 647 "vol->mft_zone_start 0x%llx, " 648 "vol->mft_zone_end 0x%llx, " 649 "vol->mft_zone_pos 0x%llx, search_zone 2, " 650 "pass 2, dones_zones 0x%x, zone_start 0x%llx, " 651 "zone_end 0x%llx, vol->data1_zone_pos 0x%llx, " 652 "continuing outer while loop.", 653 (unsigned long long)mft_zone_size, 654 (unsigned long long)vol->mft_zone_start, 655 (unsigned long long)vol->mft_zone_end, 656 (unsigned long long)vol->mft_zone_pos, 657 done_zones, (unsigned long long)zone_start, 658 (unsigned long long)zone_end, 659 (unsigned long long)vol->data1_zone_pos); 660 } 661 ntfs_debug("After outer while loop."); 662out: 663 ntfs_debug("At out."); 664 /* Add runlist terminator element. */ 665 if (likely(rl)) { 666 rl[rlpos].vcn = rl[rlpos - 1].vcn + rl[rlpos - 1].length; 667 rl[rlpos].lcn = is_extension ? LCN_ENOENT : LCN_RL_NOT_MAPPED; 668 rl[rlpos].length = 0; 669 } 670 if (likely(page && !IS_ERR(page))) { 671 if (need_writeback) { 672 ntfs_debug("Marking page dirty."); 673 flush_dcache_page(page); 674 set_page_dirty(page); 675 need_writeback = 0; 676 } 677 ntfs_unmap_page(page); 678 } 679 if (likely(!err)) { 680 up_write(&vol->lcnbmp_lock); 681 ntfs_debug("Done."); 682 return rl; 683 } 684 ntfs_error(vol->sb, "Failed to allocate clusters, aborting " 685 "(error %i).", err); 686 if (rl) { 687 int err2; 688 689 if (err == -ENOSPC) 690 ntfs_debug("Not enough space to complete allocation, " 691 "err -ENOSPC, first free lcn 0x%llx, " 692 "could allocate up to 0x%llx " 693 "clusters.", 694 (unsigned long long)rl[0].lcn, 695 (unsigned long long)(count - clusters)); 696 /* Deallocate all allocated clusters. */ 697 ntfs_debug("Attempting rollback..."); 698 err2 = ntfs_cluster_free_from_rl_nolock(vol, rl); 699 if (err2) { 700 ntfs_error(vol->sb, "Failed to rollback (error %i). " 701 "Leaving inconsistent metadata! " 702 "Unmount and run chkdsk.", err2); 703 NVolSetErrors(vol); 704 } 705 /* Free the runlist. */ 706 ntfs_free(rl); 707 } else if (err == -ENOSPC) 708 ntfs_debug("No space left at all, err = -ENOSPC, first free " 709 "lcn = 0x%llx.", 710 (long long)vol->data1_zone_pos); 711 up_write(&vol->lcnbmp_lock); 712 return ERR_PTR(err); 713} 714 715/** 716 * __ntfs_cluster_free - free clusters on an ntfs volume 717 * @ni: ntfs inode whose runlist describes the clusters to free 718 * @start_vcn: vcn in the runlist of @ni at which to start freeing clusters 719 * @count: number of clusters to free or -1 for all clusters 720 * @ctx: active attribute search context if present or NULL if not 721 * @is_rollback: true if this is a rollback operation 722 * 723 * Free @count clusters starting at the cluster @start_vcn in the runlist 724 * described by the vfs inode @ni. 725 * 726 * If @count is -1, all clusters from @start_vcn to the end of the runlist are 727 * deallocated. Thus, to completely free all clusters in a runlist, use 728 * @start_vcn = 0 and @count = -1. 729 * 730 * If @ctx is specified, it is an active search context of @ni and its base mft 731 * record. This is needed when __ntfs_cluster_free() encounters unmapped 732 * runlist fragments and allows their mapping. If you do not have the mft 733 * record mapped, you can specify @ctx as NULL and __ntfs_cluster_free() will 734 * perform the necessary mapping and unmapping. 735 * 736 * Note, __ntfs_cluster_free() saves the state of @ctx on entry and restores it 737 * before returning. Thus, @ctx will be left pointing to the same attribute on 738 * return as on entry. However, the actual pointers in @ctx may point to 739 * different memory locations on return, so you must remember to reset any 740 * cached pointers from the @ctx, i.e. after the call to __ntfs_cluster_free(), 741 * you will probably want to do: 742 * m = ctx->mrec; 743 * a = ctx->attr; 744 * Assuming you cache ctx->attr in a variable @a of type ATTR_RECORD * and that 745 * you cache ctx->mrec in a variable @m of type MFT_RECORD *. 746 * 747 * @is_rollback should always be 'false', it is for internal use to rollback 748 * errors. You probably want to use ntfs_cluster_free() instead. 749 * 750 * Note, __ntfs_cluster_free() does not modify the runlist, so you have to 751 * remove from the runlist or mark sparse the freed runs later. 752 * 753 * Return the number of deallocated clusters (not counting sparse ones) on 754 * success and -errno on error. 755 * 756 * WARNING: If @ctx is supplied, regardless of whether success or failure is 757 * returned, you need to check IS_ERR(@ctx->mrec) and if 'true' the @ctx 758 * is no longer valid, i.e. you need to either call 759 * ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it. 760 * In that case PTR_ERR(@ctx->mrec) will give you the error code for 761 * why the mapping of the old inode failed. 762 * 763 * Locking: - The runlist described by @ni must be locked for writing on entry 764 * and is locked on return. Note the runlist may be modified when 765 * needed runlist fragments need to be mapped. 766 * - The volume lcn bitmap must be unlocked on entry and is unlocked 767 * on return. 768 * - This function takes the volume lcn bitmap lock for writing and 769 * modifies the bitmap contents. 770 * - If @ctx is NULL, the base mft record of @ni must not be mapped on 771 * entry and it will be left unmapped on return. 772 * - If @ctx is not NULL, the base mft record must be mapped on entry 773 * and it will be left mapped on return. 774 */ 775s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, s64 count, 776 ntfs_attr_search_ctx *ctx, const bool is_rollback) 777{ 778 s64 delta, to_free, total_freed, real_freed; 779 ntfs_volume *vol; 780 struct inode *lcnbmp_vi; 781 runlist_element *rl; 782 int err; 783 784 BUG_ON(!ni); 785 ntfs_debug("Entering for i_ino 0x%lx, start_vcn 0x%llx, count " 786 "0x%llx.%s", ni->mft_no, (unsigned long long)start_vcn, 787 (unsigned long long)count, 788 is_rollback ? " (rollback)" : ""); 789 vol = ni->vol; 790 lcnbmp_vi = vol->lcnbmp_ino; 791 BUG_ON(!lcnbmp_vi); 792 BUG_ON(start_vcn < 0); 793 BUG_ON(count < -1); 794 /* 795 * Lock the lcn bitmap for writing but only if not rolling back. We 796 * must hold the lock all the way including through rollback otherwise 797 * rollback is not possible because once we have cleared a bit and 798 * dropped the lock, anyone could have set the bit again, thus 799 * allocating the cluster for another use. 800 */ 801 if (likely(!is_rollback)) 802 down_write(&vol->lcnbmp_lock); 803 804 total_freed = real_freed = 0; 805 806 rl = ntfs_attr_find_vcn_nolock(ni, start_vcn, ctx); 807 if (IS_ERR(rl)) { 808 if (!is_rollback) 809 ntfs_error(vol->sb, "Failed to find first runlist " 810 "element (error %li), aborting.", 811 PTR_ERR(rl)); 812 err = PTR_ERR(rl); 813 goto err_out; 814 } 815 if (unlikely(rl->lcn < LCN_HOLE)) { 816 if (!is_rollback) 817 ntfs_error(vol->sb, "First runlist element has " 818 "invalid lcn, aborting."); 819 err = -EIO; 820 goto err_out; 821 } 822 /* Find the starting cluster inside the run that needs freeing. */ 823 delta = start_vcn - rl->vcn; 824 825 /* The number of clusters in this run that need freeing. */ 826 to_free = rl->length - delta; 827 if (count >= 0 && to_free > count) 828 to_free = count; 829 830 if (likely(rl->lcn >= 0)) { 831 /* Do the actual freeing of the clusters in this run. */ 832 err = ntfs_bitmap_set_bits_in_run(lcnbmp_vi, rl->lcn + delta, 833 to_free, likely(!is_rollback) ? 0 : 1); 834 if (unlikely(err)) { 835 if (!is_rollback) 836 ntfs_error(vol->sb, "Failed to clear first run " 837 "(error %i), aborting.", err); 838 goto err_out; 839 } 840 /* We have freed @to_free real clusters. */ 841 real_freed = to_free; 842 }; 843 /* Go to the next run and adjust the number of clusters left to free. */ 844 ++rl; 845 if (count >= 0) 846 count -= to_free; 847 848 /* Keep track of the total "freed" clusters, including sparse ones. */ 849 total_freed = to_free; 850 /* 851 * Loop over the remaining runs, using @count as a capping value, and 852 * free them. 853 */ 854 for (; rl->length && count != 0; ++rl) { 855 if (unlikely(rl->lcn < LCN_HOLE)) { 856 VCN vcn; 857 858 /* Attempt to map runlist. */ 859 vcn = rl->vcn; 860 rl = ntfs_attr_find_vcn_nolock(ni, vcn, ctx); 861 if (IS_ERR(rl)) { 862 err = PTR_ERR(rl); 863 if (!is_rollback) 864 ntfs_error(vol->sb, "Failed to map " 865 "runlist fragment or " 866 "failed to find " 867 "subsequent runlist " 868 "element."); 869 goto err_out; 870 } 871 if (unlikely(rl->lcn < LCN_HOLE)) { 872 if (!is_rollback) 873 ntfs_error(vol->sb, "Runlist element " 874 "has invalid lcn " 875 "(0x%llx).", 876 (unsigned long long) 877 rl->lcn); 878 err = -EIO; 879 goto err_out; 880 } 881 } 882 /* The number of clusters in this run that need freeing. */ 883 to_free = rl->length; 884 if (count >= 0 && to_free > count) 885 to_free = count; 886 887 if (likely(rl->lcn >= 0)) { 888 /* Do the actual freeing of the clusters in the run. */ 889 err = ntfs_bitmap_set_bits_in_run(lcnbmp_vi, rl->lcn, 890 to_free, likely(!is_rollback) ? 0 : 1); 891 if (unlikely(err)) { 892 if (!is_rollback) 893 ntfs_error(vol->sb, "Failed to clear " 894 "subsequent run."); 895 goto err_out; 896 } 897 /* We have freed @to_free real clusters. */ 898 real_freed += to_free; 899 } 900 /* Adjust the number of clusters left to free. */ 901 if (count >= 0) 902 count -= to_free; 903 904 /* Update the total done clusters. */ 905 total_freed += to_free; 906 } 907 if (likely(!is_rollback)) 908 up_write(&vol->lcnbmp_lock); 909 910 BUG_ON(count > 0); 911 912 /* We are done. Return the number of actually freed clusters. */ 913 ntfs_debug("Done."); 914 return real_freed; 915err_out: 916 if (is_rollback) 917 return err; 918 /* If no real clusters were freed, no need to rollback. */ 919 if (!real_freed) { 920 up_write(&vol->lcnbmp_lock); 921 return err; 922 } 923 /* 924 * Attempt to rollback and if that succeeds just return the error code. 925 * If rollback fails, set the volume errors flag, emit an error 926 * message, and return the error code. 927 */ 928 delta = __ntfs_cluster_free(ni, start_vcn, total_freed, ctx, true); 929 if (delta < 0) { 930 ntfs_error(vol->sb, "Failed to rollback (error %i). Leaving " 931 "inconsistent metadata! Unmount and run " 932 "chkdsk.", (int)delta); 933 NVolSetErrors(vol); 934 } 935 up_write(&vol->lcnbmp_lock); 936 ntfs_error(vol->sb, "Aborting (error %i).", err); 937 return err; 938} 939 940#endif /* NTFS_RW */ 941