1 /* 2 * balloc.c 3 * 4 * PURPOSE 5 * Block allocation handling routines for the OSTA-UDF(tm) filesystem. 6 * 7 * COPYRIGHT 8 * This file is distributed under the terms of the GNU General Public 9 * License (GPL). Copies of the GPL can be obtained from: 10 * ftp://prep.ai.mit.edu/pub/gnu/GPL 11 * Each contributing author retains all rights to their own work. 12 * 13 * (C) 1999-2001 Ben Fennema 14 * (C) 1999 Stelias Computing Inc 15 * 16 * HISTORY 17 * 18 * 02/24/99 blf Created. 19 * 20 */ 21 22 #include "udfdecl.h" 23 24 #include <linux/bitops.h> 25 26 #include "udf_i.h" 27 #include "udf_sb.h" 28 29 #define udf_clear_bit __test_and_clear_bit_le 30 #define udf_set_bit __test_and_set_bit_le 31 #define udf_test_bit test_bit_le 32 #define udf_find_next_one_bit find_next_bit_le 33 34 static int read_block_bitmap(struct super_block *sb, 35 struct udf_bitmap *bitmap, unsigned int block, 36 unsigned long bitmap_nr) 37 { 38 struct buffer_head *bh = NULL; 39 int retval = 0; 40 struct kernel_lb_addr loc; 41 42 loc.logicalBlockNum = bitmap->s_extPosition; 43 loc.partitionReferenceNum = UDF_SB(sb)->s_partition; 44 45 bh = udf_tread(sb, udf_get_lb_pblock(sb, &loc, block)); 46 if (!bh) 47 retval = -EIO; 48 49 bitmap->s_block_bitmap[bitmap_nr] = bh; 50 return retval; 51 } 52 53 static int __load_block_bitmap(struct super_block *sb, 54 struct udf_bitmap *bitmap, 55 unsigned int block_group) 56 { 57 int retval = 0; 58 int nr_groups = bitmap->s_nr_groups; 59 60 if (block_group >= nr_groups) { 61 udf_debug("block_group (%d) > nr_groups (%d)\n", 62 block_group, nr_groups); 63 } 64 65 if (bitmap->s_block_bitmap[block_group]) 66 return block_group; 67 68 retval = read_block_bitmap(sb, bitmap, block_group, block_group); 69 if (retval < 0) 70 return retval; 71 72 return block_group; 73 } 74 75 static inline int load_block_bitmap(struct super_block *sb, 76 struct udf_bitmap *bitmap, 77 unsigned int block_group) 78 { 79 int slot; 80 81 slot = __load_block_bitmap(sb, bitmap, block_group); 82 83 if (slot < 0) 84 return slot; 85 86 if (!bitmap->s_block_bitmap[slot]) 87 return -EIO; 88 89 return slot; 90 } 91 92 static void udf_add_free_space(struct super_block *sb, u16 partition, u32 cnt) 93 { 94 struct udf_sb_info *sbi = UDF_SB(sb); 95 struct logicalVolIntegrityDesc *lvid; 96 97 if (!sbi->s_lvid_bh) 98 return; 99 100 lvid = (struct logicalVolIntegrityDesc *)sbi->s_lvid_bh->b_data; 101 le32_add_cpu(&lvid->freeSpaceTable[partition], cnt); 102 udf_updated_lvid(sb); 103 } 104 105 static void udf_bitmap_free_blocks(struct super_block *sb, 106 struct udf_bitmap *bitmap, 107 struct kernel_lb_addr *bloc, 108 uint32_t offset, 109 uint32_t count) 110 { 111 struct udf_sb_info *sbi = UDF_SB(sb); 112 struct buffer_head *bh = NULL; 113 struct udf_part_map *partmap; 114 unsigned long block; 115 unsigned long block_group; 116 unsigned long bit; 117 unsigned long i; 118 int bitmap_nr; 119 unsigned long overflow; 120 121 mutex_lock(&sbi->s_alloc_mutex); 122 partmap = &sbi->s_partmaps[bloc->partitionReferenceNum]; 123 if (bloc->logicalBlockNum + count < count || 124 (bloc->logicalBlockNum + count) > partmap->s_partition_len) { 125 udf_debug("%d < %d || %d + %d > %d\n", 126 bloc->logicalBlockNum, 0, 127 bloc->logicalBlockNum, count, 128 partmap->s_partition_len); 129 goto error_return; 130 } 131 132 block = bloc->logicalBlockNum + offset + 133 (sizeof(struct spaceBitmapDesc) << 3); 134 135 do { 136 overflow = 0; 137 block_group = block >> (sb->s_blocksize_bits + 3); 138 bit = block % (sb->s_blocksize << 3); 139 140 /* 141 * Check to see if we are freeing blocks across a group boundary. 142 */ 143 if (bit + count > (sb->s_blocksize << 3)) { 144 overflow = bit + count - (sb->s_blocksize << 3); 145 count -= overflow; 146 } 147 bitmap_nr = load_block_bitmap(sb, bitmap, block_group); 148 if (bitmap_nr < 0) 149 goto error_return; 150 151 bh = bitmap->s_block_bitmap[bitmap_nr]; 152 for (i = 0; i < count; i++) { 153 if (udf_set_bit(bit + i, bh->b_data)) { 154 udf_debug("bit %ld already set\n", bit + i); 155 udf_debug("byte=%2x\n", 156 ((char *)bh->b_data)[(bit + i) >> 3]); 157 } 158 } 159 udf_add_free_space(sb, sbi->s_partition, count); 160 mark_buffer_dirty(bh); 161 if (overflow) { 162 block += count; 163 count = overflow; 164 } 165 } while (overflow); 166 167 error_return: 168 mutex_unlock(&sbi->s_alloc_mutex); 169 } 170 171 static int udf_bitmap_prealloc_blocks(struct super_block *sb, 172 struct udf_bitmap *bitmap, 173 uint16_t partition, uint32_t first_block, 174 uint32_t block_count) 175 { 176 struct udf_sb_info *sbi = UDF_SB(sb); 177 int alloc_count = 0; 178 int bit, block, block_group, group_start; 179 int nr_groups, bitmap_nr; 180 struct buffer_head *bh; 181 __u32 part_len; 182 183 mutex_lock(&sbi->s_alloc_mutex); 184 part_len = sbi->s_partmaps[partition].s_partition_len; 185 if (first_block >= part_len) 186 goto out; 187 188 if (first_block + block_count > part_len) 189 block_count = part_len - first_block; 190 191 do { 192 nr_groups = udf_compute_nr_groups(sb, partition); 193 block = first_block + (sizeof(struct spaceBitmapDesc) << 3); 194 block_group = block >> (sb->s_blocksize_bits + 3); 195 group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc); 196 197 bitmap_nr = load_block_bitmap(sb, bitmap, block_group); 198 if (bitmap_nr < 0) 199 goto out; 200 bh = bitmap->s_block_bitmap[bitmap_nr]; 201 202 bit = block % (sb->s_blocksize << 3); 203 204 while (bit < (sb->s_blocksize << 3) && block_count > 0) { 205 if (!udf_clear_bit(bit, bh->b_data)) 206 goto out; 207 block_count--; 208 alloc_count++; 209 bit++; 210 block++; 211 } 212 mark_buffer_dirty(bh); 213 } while (block_count > 0); 214 215 out: 216 udf_add_free_space(sb, partition, -alloc_count); 217 mutex_unlock(&sbi->s_alloc_mutex); 218 return alloc_count; 219 } 220 221 static int udf_bitmap_new_block(struct super_block *sb, 222 struct udf_bitmap *bitmap, uint16_t partition, 223 uint32_t goal, int *err) 224 { 225 struct udf_sb_info *sbi = UDF_SB(sb); 226 int newbit, bit = 0, block, block_group, group_start; 227 int end_goal, nr_groups, bitmap_nr, i; 228 struct buffer_head *bh = NULL; 229 char *ptr; 230 int newblock = 0; 231 232 *err = -ENOSPC; 233 mutex_lock(&sbi->s_alloc_mutex); 234 235 repeat: 236 if (goal >= sbi->s_partmaps[partition].s_partition_len) 237 goal = 0; 238 239 nr_groups = bitmap->s_nr_groups; 240 block = goal + (sizeof(struct spaceBitmapDesc) << 3); 241 block_group = block >> (sb->s_blocksize_bits + 3); 242 group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc); 243 244 bitmap_nr = load_block_bitmap(sb, bitmap, block_group); 245 if (bitmap_nr < 0) 246 goto error_return; 247 bh = bitmap->s_block_bitmap[bitmap_nr]; 248 ptr = memscan((char *)bh->b_data + group_start, 0xFF, 249 sb->s_blocksize - group_start); 250 251 if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) { 252 bit = block % (sb->s_blocksize << 3); 253 if (udf_test_bit(bit, bh->b_data)) 254 goto got_block; 255 256 end_goal = (bit + 63) & ~63; 257 bit = udf_find_next_one_bit(bh->b_data, end_goal, bit); 258 if (bit < end_goal) 259 goto got_block; 260 261 ptr = memscan((char *)bh->b_data + (bit >> 3), 0xFF, 262 sb->s_blocksize - ((bit + 7) >> 3)); 263 newbit = (ptr - ((char *)bh->b_data)) << 3; 264 if (newbit < sb->s_blocksize << 3) { 265 bit = newbit; 266 goto search_back; 267 } 268 269 newbit = udf_find_next_one_bit(bh->b_data, 270 sb->s_blocksize << 3, bit); 271 if (newbit < sb->s_blocksize << 3) { 272 bit = newbit; 273 goto got_block; 274 } 275 } 276 277 for (i = 0; i < (nr_groups * 2); i++) { 278 block_group++; 279 if (block_group >= nr_groups) 280 block_group = 0; 281 group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc); 282 283 bitmap_nr = load_block_bitmap(sb, bitmap, block_group); 284 if (bitmap_nr < 0) 285 goto error_return; 286 bh = bitmap->s_block_bitmap[bitmap_nr]; 287 if (i < nr_groups) { 288 ptr = memscan((char *)bh->b_data + group_start, 0xFF, 289 sb->s_blocksize - group_start); 290 if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) { 291 bit = (ptr - ((char *)bh->b_data)) << 3; 292 break; 293 } 294 } else { 295 bit = udf_find_next_one_bit(bh->b_data, 296 sb->s_blocksize << 3, 297 group_start << 3); 298 if (bit < sb->s_blocksize << 3) 299 break; 300 } 301 } 302 if (i >= (nr_groups * 2)) { 303 mutex_unlock(&sbi->s_alloc_mutex); 304 return newblock; 305 } 306 if (bit < sb->s_blocksize << 3) 307 goto search_back; 308 else 309 bit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3, 310 group_start << 3); 311 if (bit >= sb->s_blocksize << 3) { 312 mutex_unlock(&sbi->s_alloc_mutex); 313 return 0; 314 } 315 316 search_back: 317 i = 0; 318 while (i < 7 && bit > (group_start << 3) && 319 udf_test_bit(bit - 1, bh->b_data)) { 320 ++i; 321 --bit; 322 } 323 324 got_block: 325 newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) - 326 (sizeof(struct spaceBitmapDesc) << 3); 327 328 if (!udf_clear_bit(bit, bh->b_data)) { 329 udf_debug("bit already cleared for block %d\n", bit); 330 goto repeat; 331 } 332 333 mark_buffer_dirty(bh); 334 335 udf_add_free_space(sb, partition, -1); 336 mutex_unlock(&sbi->s_alloc_mutex); 337 *err = 0; 338 return newblock; 339 340 error_return: 341 *err = -EIO; 342 mutex_unlock(&sbi->s_alloc_mutex); 343 return 0; 344 } 345 346 static void udf_table_free_blocks(struct super_block *sb, 347 struct inode *table, 348 struct kernel_lb_addr *bloc, 349 uint32_t offset, 350 uint32_t count) 351 { 352 struct udf_sb_info *sbi = UDF_SB(sb); 353 struct udf_part_map *partmap; 354 uint32_t start, end; 355 uint32_t elen; 356 struct kernel_lb_addr eloc; 357 struct extent_position oepos, epos; 358 int8_t etype; 359 struct udf_inode_info *iinfo; 360 361 mutex_lock(&sbi->s_alloc_mutex); 362 partmap = &sbi->s_partmaps[bloc->partitionReferenceNum]; 363 if (bloc->logicalBlockNum + count < count || 364 (bloc->logicalBlockNum + count) > partmap->s_partition_len) { 365 udf_debug("%d < %d || %d + %d > %d\n", 366 bloc->logicalBlockNum, 0, 367 bloc->logicalBlockNum, count, 368 partmap->s_partition_len); 369 goto error_return; 370 } 371 372 iinfo = UDF_I(table); 373 udf_add_free_space(sb, sbi->s_partition, count); 374 375 start = bloc->logicalBlockNum + offset; 376 end = bloc->logicalBlockNum + offset + count - 1; 377 378 epos.offset = oepos.offset = sizeof(struct unallocSpaceEntry); 379 elen = 0; 380 epos.block = oepos.block = iinfo->i_location; 381 epos.bh = oepos.bh = NULL; 382 383 while (count && 384 (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) { 385 if (((eloc.logicalBlockNum + 386 (elen >> sb->s_blocksize_bits)) == start)) { 387 if ((0x3FFFFFFF - elen) < 388 (count << sb->s_blocksize_bits)) { 389 uint32_t tmp = ((0x3FFFFFFF - elen) >> 390 sb->s_blocksize_bits); 391 count -= tmp; 392 start += tmp; 393 elen = (etype << 30) | 394 (0x40000000 - sb->s_blocksize); 395 } else { 396 elen = (etype << 30) | 397 (elen + 398 (count << sb->s_blocksize_bits)); 399 start += count; 400 count = 0; 401 } 402 udf_write_aext(table, &oepos, &eloc, elen, 1); 403 } else if (eloc.logicalBlockNum == (end + 1)) { 404 if ((0x3FFFFFFF - elen) < 405 (count << sb->s_blocksize_bits)) { 406 uint32_t tmp = ((0x3FFFFFFF - elen) >> 407 sb->s_blocksize_bits); 408 count -= tmp; 409 end -= tmp; 410 eloc.logicalBlockNum -= tmp; 411 elen = (etype << 30) | 412 (0x40000000 - sb->s_blocksize); 413 } else { 414 eloc.logicalBlockNum = start; 415 elen = (etype << 30) | 416 (elen + 417 (count << sb->s_blocksize_bits)); 418 end -= count; 419 count = 0; 420 } 421 udf_write_aext(table, &oepos, &eloc, elen, 1); 422 } 423 424 if (epos.bh != oepos.bh) { 425 oepos.block = epos.block; 426 brelse(oepos.bh); 427 get_bh(epos.bh); 428 oepos.bh = epos.bh; 429 oepos.offset = 0; 430 } else { 431 oepos.offset = epos.offset; 432 } 433 } 434 435 if (count) { 436 /* 437 * NOTE: we CANNOT use udf_add_aext here, as it can try to 438 * allocate a new block, and since we hold the super block 439 * lock already very bad things would happen :) 440 * 441 * We copy the behavior of udf_add_aext, but instead of 442 * trying to allocate a new block close to the existing one, 443 * we just steal a block from the extent we are trying to add. 444 * 445 * It would be nice if the blocks were close together, but it 446 * isn't required. 447 */ 448 449 int adsize; 450 struct short_ad *sad = NULL; 451 struct long_ad *lad = NULL; 452 struct allocExtDesc *aed; 453 454 eloc.logicalBlockNum = start; 455 elen = EXT_RECORDED_ALLOCATED | 456 (count << sb->s_blocksize_bits); 457 458 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT) 459 adsize = sizeof(struct short_ad); 460 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG) 461 adsize = sizeof(struct long_ad); 462 else { 463 brelse(oepos.bh); 464 brelse(epos.bh); 465 goto error_return; 466 } 467 468 if (epos.offset + (2 * adsize) > sb->s_blocksize) { 469 unsigned char *sptr, *dptr; 470 int loffset; 471 472 brelse(oepos.bh); 473 oepos = epos; 474 475 /* Steal a block from the extent being free'd */ 476 epos.block.logicalBlockNum = eloc.logicalBlockNum; 477 eloc.logicalBlockNum++; 478 elen -= sb->s_blocksize; 479 480 epos.bh = udf_tread(sb, 481 udf_get_lb_pblock(sb, &epos.block, 0)); 482 if (!epos.bh) { 483 brelse(oepos.bh); 484 goto error_return; 485 } 486 aed = (struct allocExtDesc *)(epos.bh->b_data); 487 aed->previousAllocExtLocation = 488 cpu_to_le32(oepos.block.logicalBlockNum); 489 if (epos.offset + adsize > sb->s_blocksize) { 490 loffset = epos.offset; 491 aed->lengthAllocDescs = cpu_to_le32(adsize); 492 sptr = iinfo->i_ext.i_data + epos.offset 493 - adsize; 494 dptr = epos.bh->b_data + 495 sizeof(struct allocExtDesc); 496 memcpy(dptr, sptr, adsize); 497 epos.offset = sizeof(struct allocExtDesc) + 498 adsize; 499 } else { 500 loffset = epos.offset + adsize; 501 aed->lengthAllocDescs = cpu_to_le32(0); 502 if (oepos.bh) { 503 sptr = oepos.bh->b_data + epos.offset; 504 aed = (struct allocExtDesc *) 505 oepos.bh->b_data; 506 le32_add_cpu(&aed->lengthAllocDescs, 507 adsize); 508 } else { 509 sptr = iinfo->i_ext.i_data + 510 epos.offset; 511 iinfo->i_lenAlloc += adsize; 512 mark_inode_dirty(table); 513 } 514 epos.offset = sizeof(struct allocExtDesc); 515 } 516 if (sbi->s_udfrev >= 0x0200) 517 udf_new_tag(epos.bh->b_data, TAG_IDENT_AED, 518 3, 1, epos.block.logicalBlockNum, 519 sizeof(struct tag)); 520 else 521 udf_new_tag(epos.bh->b_data, TAG_IDENT_AED, 522 2, 1, epos.block.logicalBlockNum, 523 sizeof(struct tag)); 524 525 switch (iinfo->i_alloc_type) { 526 case ICBTAG_FLAG_AD_SHORT: 527 sad = (struct short_ad *)sptr; 528 sad->extLength = cpu_to_le32( 529 EXT_NEXT_EXTENT_ALLOCDECS | 530 sb->s_blocksize); 531 sad->extPosition = 532 cpu_to_le32(epos.block.logicalBlockNum); 533 break; 534 case ICBTAG_FLAG_AD_LONG: 535 lad = (struct long_ad *)sptr; 536 lad->extLength = cpu_to_le32( 537 EXT_NEXT_EXTENT_ALLOCDECS | 538 sb->s_blocksize); 539 lad->extLocation = 540 cpu_to_lelb(epos.block); 541 break; 542 } 543 if (oepos.bh) { 544 udf_update_tag(oepos.bh->b_data, loffset); 545 mark_buffer_dirty(oepos.bh); 546 } else { 547 mark_inode_dirty(table); 548 } 549 } 550 551 /* It's possible that stealing the block emptied the extent */ 552 if (elen) { 553 udf_write_aext(table, &epos, &eloc, elen, 1); 554 555 if (!epos.bh) { 556 iinfo->i_lenAlloc += adsize; 557 mark_inode_dirty(table); 558 } else { 559 aed = (struct allocExtDesc *)epos.bh->b_data; 560 le32_add_cpu(&aed->lengthAllocDescs, adsize); 561 udf_update_tag(epos.bh->b_data, epos.offset); 562 mark_buffer_dirty(epos.bh); 563 } 564 } 565 } 566 567 brelse(epos.bh); 568 brelse(oepos.bh); 569 570 error_return: 571 mutex_unlock(&sbi->s_alloc_mutex); 572 return; 573 } 574 575 static int udf_table_prealloc_blocks(struct super_block *sb, 576 struct inode *table, uint16_t partition, 577 uint32_t first_block, uint32_t block_count) 578 { 579 struct udf_sb_info *sbi = UDF_SB(sb); 580 int alloc_count = 0; 581 uint32_t elen, adsize; 582 struct kernel_lb_addr eloc; 583 struct extent_position epos; 584 int8_t etype = -1; 585 struct udf_inode_info *iinfo; 586 587 if (first_block >= sbi->s_partmaps[partition].s_partition_len) 588 return 0; 589 590 iinfo = UDF_I(table); 591 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT) 592 adsize = sizeof(struct short_ad); 593 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG) 594 adsize = sizeof(struct long_ad); 595 else 596 return 0; 597 598 mutex_lock(&sbi->s_alloc_mutex); 599 epos.offset = sizeof(struct unallocSpaceEntry); 600 epos.block = iinfo->i_location; 601 epos.bh = NULL; 602 eloc.logicalBlockNum = 0xFFFFFFFF; 603 604 while (first_block != eloc.logicalBlockNum && 605 (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) { 606 udf_debug("eloc=%d, elen=%d, first_block=%d\n", 607 eloc.logicalBlockNum, elen, first_block); 608 ; /* empty loop body */ 609 } 610 611 if (first_block == eloc.logicalBlockNum) { 612 epos.offset -= adsize; 613 614 alloc_count = (elen >> sb->s_blocksize_bits); 615 if (alloc_count > block_count) { 616 alloc_count = block_count; 617 eloc.logicalBlockNum += alloc_count; 618 elen -= (alloc_count << sb->s_blocksize_bits); 619 udf_write_aext(table, &epos, &eloc, 620 (etype << 30) | elen, 1); 621 } else 622 udf_delete_aext(table, epos, eloc, 623 (etype << 30) | elen); 624 } else { 625 alloc_count = 0; 626 } 627 628 brelse(epos.bh); 629 630 if (alloc_count) 631 udf_add_free_space(sb, partition, -alloc_count); 632 mutex_unlock(&sbi->s_alloc_mutex); 633 return alloc_count; 634 } 635 636 static int udf_table_new_block(struct super_block *sb, 637 struct inode *table, uint16_t partition, 638 uint32_t goal, int *err) 639 { 640 struct udf_sb_info *sbi = UDF_SB(sb); 641 uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF; 642 uint32_t newblock = 0, adsize; 643 uint32_t elen, goal_elen = 0; 644 struct kernel_lb_addr eloc, uninitialized_var(goal_eloc); 645 struct extent_position epos, goal_epos; 646 int8_t etype; 647 struct udf_inode_info *iinfo = UDF_I(table); 648 649 *err = -ENOSPC; 650 651 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT) 652 adsize = sizeof(struct short_ad); 653 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG) 654 adsize = sizeof(struct long_ad); 655 else 656 return newblock; 657 658 mutex_lock(&sbi->s_alloc_mutex); 659 if (goal >= sbi->s_partmaps[partition].s_partition_len) 660 goal = 0; 661 662 /* We search for the closest matching block to goal. If we find 663 a exact hit, we stop. Otherwise we keep going till we run out 664 of extents. We store the buffer_head, bloc, and extoffset 665 of the current closest match and use that when we are done. 666 */ 667 epos.offset = sizeof(struct unallocSpaceEntry); 668 epos.block = iinfo->i_location; 669 epos.bh = goal_epos.bh = NULL; 670 671 while (spread && 672 (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) { 673 if (goal >= eloc.logicalBlockNum) { 674 if (goal < eloc.logicalBlockNum + 675 (elen >> sb->s_blocksize_bits)) 676 nspread = 0; 677 else 678 nspread = goal - eloc.logicalBlockNum - 679 (elen >> sb->s_blocksize_bits); 680 } else { 681 nspread = eloc.logicalBlockNum - goal; 682 } 683 684 if (nspread < spread) { 685 spread = nspread; 686 if (goal_epos.bh != epos.bh) { 687 brelse(goal_epos.bh); 688 goal_epos.bh = epos.bh; 689 get_bh(goal_epos.bh); 690 } 691 goal_epos.block = epos.block; 692 goal_epos.offset = epos.offset - adsize; 693 goal_eloc = eloc; 694 goal_elen = (etype << 30) | elen; 695 } 696 } 697 698 brelse(epos.bh); 699 700 if (spread == 0xFFFFFFFF) { 701 brelse(goal_epos.bh); 702 mutex_unlock(&sbi->s_alloc_mutex); 703 return 0; 704 } 705 706 /* Only allocate blocks from the beginning of the extent. 707 That way, we only delete (empty) extents, never have to insert an 708 extent because of splitting */ 709 /* This works, but very poorly.... */ 710 711 newblock = goal_eloc.logicalBlockNum; 712 goal_eloc.logicalBlockNum++; 713 goal_elen -= sb->s_blocksize; 714 715 if (goal_elen) 716 udf_write_aext(table, &goal_epos, &goal_eloc, goal_elen, 1); 717 else 718 udf_delete_aext(table, goal_epos, goal_eloc, goal_elen); 719 brelse(goal_epos.bh); 720 721 udf_add_free_space(sb, partition, -1); 722 723 mutex_unlock(&sbi->s_alloc_mutex); 724 *err = 0; 725 return newblock; 726 } 727 728 void udf_free_blocks(struct super_block *sb, struct inode *inode, 729 struct kernel_lb_addr *bloc, uint32_t offset, 730 uint32_t count) 731 { 732 uint16_t partition = bloc->partitionReferenceNum; 733 struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition]; 734 735 if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) { 736 udf_bitmap_free_blocks(sb, map->s_uspace.s_bitmap, 737 bloc, offset, count); 738 } else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) { 739 udf_table_free_blocks(sb, map->s_uspace.s_table, 740 bloc, offset, count); 741 } else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) { 742 udf_bitmap_free_blocks(sb, map->s_fspace.s_bitmap, 743 bloc, offset, count); 744 } else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) { 745 udf_table_free_blocks(sb, map->s_fspace.s_table, 746 bloc, offset, count); 747 } 748 749 if (inode) { 750 inode_sub_bytes(inode, 751 ((sector_t)count) << sb->s_blocksize_bits); 752 } 753 } 754 755 inline int udf_prealloc_blocks(struct super_block *sb, 756 struct inode *inode, 757 uint16_t partition, uint32_t first_block, 758 uint32_t block_count) 759 { 760 struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition]; 761 int allocated; 762 763 if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) 764 allocated = udf_bitmap_prealloc_blocks(sb, 765 map->s_uspace.s_bitmap, 766 partition, first_block, 767 block_count); 768 else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) 769 allocated = udf_table_prealloc_blocks(sb, 770 map->s_uspace.s_table, 771 partition, first_block, 772 block_count); 773 else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) 774 allocated = udf_bitmap_prealloc_blocks(sb, 775 map->s_fspace.s_bitmap, 776 partition, first_block, 777 block_count); 778 else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) 779 allocated = udf_table_prealloc_blocks(sb, 780 map->s_fspace.s_table, 781 partition, first_block, 782 block_count); 783 else 784 return 0; 785 786 if (inode && allocated > 0) 787 inode_add_bytes(inode, allocated << sb->s_blocksize_bits); 788 return allocated; 789 } 790 791 inline int udf_new_block(struct super_block *sb, 792 struct inode *inode, 793 uint16_t partition, uint32_t goal, int *err) 794 { 795 struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition]; 796 int block; 797 798 if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) 799 block = udf_bitmap_new_block(sb, 800 map->s_uspace.s_bitmap, 801 partition, goal, err); 802 else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) 803 block = udf_table_new_block(sb, 804 map->s_uspace.s_table, 805 partition, goal, err); 806 else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) 807 block = udf_bitmap_new_block(sb, 808 map->s_fspace.s_bitmap, 809 partition, goal, err); 810 else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) 811 block = udf_table_new_block(sb, 812 map->s_fspace.s_table, 813 partition, goal, err); 814 else { 815 *err = -EIO; 816 return 0; 817 } 818 if (inode && block) 819 inode_add_bytes(inode, sb->s_blocksize); 820 return block; 821 } 822