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/quotaops.h> 25 #include <linux/buffer_head.h> 26 #include <linux/bitops.h> 27 28 #include "udf_i.h" 29 #include "udf_sb.h" 30 31 #define udf_clear_bit(nr,addr) ext2_clear_bit(nr,addr) 32 #define udf_set_bit(nr,addr) ext2_set_bit(nr,addr) 33 #define udf_test_bit(nr, addr) ext2_test_bit(nr, addr) 34 #define udf_find_first_one_bit(addr, size) find_first_one_bit(addr, size) 35 #define udf_find_next_one_bit(addr, size, offset) find_next_one_bit(addr, size, offset) 36 37 #define leBPL_to_cpup(x) leNUM_to_cpup(BITS_PER_LONG, x) 38 #define leNUM_to_cpup(x,y) xleNUM_to_cpup(x,y) 39 #define xleNUM_to_cpup(x,y) (le ## x ## _to_cpup(y)) 40 #define uintBPL_t uint(BITS_PER_LONG) 41 #define uint(x) xuint(x) 42 #define xuint(x) __le ## x 43 44 static inline int find_next_one_bit (void * addr, int size, int offset) 45 { 46 uintBPL_t * p = ((uintBPL_t *) addr) + (offset / BITS_PER_LONG); 47 int result = offset & ~(BITS_PER_LONG-1); 48 unsigned long tmp; 49 50 if (offset >= size) 51 return size; 52 size -= result; 53 offset &= (BITS_PER_LONG-1); 54 if (offset) 55 { 56 tmp = leBPL_to_cpup(p++); 57 tmp &= ~0UL << offset; 58 if (size < BITS_PER_LONG) 59 goto found_first; 60 if (tmp) 61 goto found_middle; 62 size -= BITS_PER_LONG; 63 result += BITS_PER_LONG; 64 } 65 while (size & ~(BITS_PER_LONG-1)) 66 { 67 if ((tmp = leBPL_to_cpup(p++))) 68 goto found_middle; 69 result += BITS_PER_LONG; 70 size -= BITS_PER_LONG; 71 } 72 if (!size) 73 return result; 74 tmp = leBPL_to_cpup(p); 75 found_first: 76 tmp &= ~0UL >> (BITS_PER_LONG-size); 77 found_middle: 78 return result + ffz(~tmp); 79 } 80 81 #define find_first_one_bit(addr, size)\ 82 find_next_one_bit((addr), (size), 0) 83 84 static int read_block_bitmap(struct super_block * sb, 85 struct udf_bitmap *bitmap, unsigned int block, unsigned long bitmap_nr) 86 { 87 struct buffer_head *bh = NULL; 88 int retval = 0; 89 kernel_lb_addr loc; 90 91 loc.logicalBlockNum = bitmap->s_extPosition; 92 loc.partitionReferenceNum = UDF_SB_PARTITION(sb); 93 94 bh = udf_tread(sb, udf_get_lb_pblock(sb, loc, block)); 95 if (!bh) 96 { 97 retval = -EIO; 98 } 99 bitmap->s_block_bitmap[bitmap_nr] = bh; 100 return retval; 101 } 102 103 static int __load_block_bitmap(struct super_block * sb, 104 struct udf_bitmap *bitmap, unsigned int block_group) 105 { 106 int retval = 0; 107 int nr_groups = bitmap->s_nr_groups; 108 109 if (block_group >= nr_groups) 110 { 111 udf_debug("block_group (%d) > nr_groups (%d)\n", block_group, nr_groups); 112 } 113 114 if (bitmap->s_block_bitmap[block_group]) 115 return block_group; 116 else 117 { 118 retval = read_block_bitmap(sb, bitmap, block_group, block_group); 119 if (retval < 0) 120 return retval; 121 return block_group; 122 } 123 } 124 125 static inline int load_block_bitmap(struct super_block * sb, 126 struct udf_bitmap *bitmap, unsigned int block_group) 127 { 128 int slot; 129 130 slot = __load_block_bitmap(sb, bitmap, block_group); 131 132 if (slot < 0) 133 return slot; 134 135 if (!bitmap->s_block_bitmap[slot]) 136 return -EIO; 137 138 return slot; 139 } 140 141 static void udf_bitmap_free_blocks(struct super_block * sb, 142 struct inode * inode, 143 struct udf_bitmap *bitmap, 144 kernel_lb_addr bloc, uint32_t offset, uint32_t count) 145 { 146 struct udf_sb_info *sbi = UDF_SB(sb); 147 struct buffer_head * bh = NULL; 148 unsigned long block; 149 unsigned long block_group; 150 unsigned long bit; 151 unsigned long i; 152 int bitmap_nr; 153 unsigned long overflow; 154 155 mutex_lock(&sbi->s_alloc_mutex); 156 if (bloc.logicalBlockNum < 0 || 157 (bloc.logicalBlockNum + count) > UDF_SB_PARTLEN(sb, bloc.partitionReferenceNum)) 158 { 159 udf_debug("%d < %d || %d + %d > %d\n", 160 bloc.logicalBlockNum, 0, bloc.logicalBlockNum, count, 161 UDF_SB_PARTLEN(sb, bloc.partitionReferenceNum)); 162 goto error_return; 163 } 164 165 block = bloc.logicalBlockNum + offset + (sizeof(struct spaceBitmapDesc) << 3); 166 167 do_more: 168 overflow = 0; 169 block_group = block >> (sb->s_blocksize_bits + 3); 170 bit = block % (sb->s_blocksize << 3); 171 172 /* 173 * Check to see if we are freeing blocks across a group boundary. 174 */ 175 if (bit + count > (sb->s_blocksize << 3)) 176 { 177 overflow = bit + count - (sb->s_blocksize << 3); 178 count -= overflow; 179 } 180 bitmap_nr = load_block_bitmap(sb, bitmap, block_group); 181 if (bitmap_nr < 0) 182 goto error_return; 183 184 bh = bitmap->s_block_bitmap[bitmap_nr]; 185 for (i=0; i < count; i++) 186 { 187 if (udf_set_bit(bit + i, bh->b_data)) 188 { 189 udf_debug("bit %ld already set\n", bit + i); 190 udf_debug("byte=%2x\n", ((char *)bh->b_data)[(bit + i) >> 3]); 191 } 192 else 193 { 194 if (inode) 195 DQUOT_FREE_BLOCK(inode, 1); 196 if (UDF_SB_LVIDBH(sb)) 197 { 198 UDF_SB_LVID(sb)->freeSpaceTable[UDF_SB_PARTITION(sb)] = 199 cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[UDF_SB_PARTITION(sb)])+1); 200 } 201 } 202 } 203 mark_buffer_dirty(bh); 204 if (overflow) 205 { 206 block += count; 207 count = overflow; 208 goto do_more; 209 } 210 error_return: 211 sb->s_dirt = 1; 212 if (UDF_SB_LVIDBH(sb)) 213 mark_buffer_dirty(UDF_SB_LVIDBH(sb)); 214 mutex_unlock(&sbi->s_alloc_mutex); 215 return; 216 } 217 218 static int udf_bitmap_prealloc_blocks(struct super_block * sb, 219 struct inode * inode, 220 struct udf_bitmap *bitmap, uint16_t partition, uint32_t first_block, 221 uint32_t block_count) 222 { 223 struct udf_sb_info *sbi = UDF_SB(sb); 224 int alloc_count = 0; 225 int bit, block, block_group, group_start; 226 int nr_groups, bitmap_nr; 227 struct buffer_head *bh; 228 229 mutex_lock(&sbi->s_alloc_mutex); 230 if (first_block < 0 || first_block >= UDF_SB_PARTLEN(sb, partition)) 231 goto out; 232 233 if (first_block + block_count > UDF_SB_PARTLEN(sb, partition)) 234 block_count = UDF_SB_PARTLEN(sb, partition) - first_block; 235 236 repeat: 237 nr_groups = (UDF_SB_PARTLEN(sb, partition) + 238 (sizeof(struct spaceBitmapDesc) << 3) + (sb->s_blocksize * 8) - 1) / (sb->s_blocksize * 8); 239 block = first_block + (sizeof(struct spaceBitmapDesc) << 3); 240 block_group = block >> (sb->s_blocksize_bits + 3); 241 group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc); 242 243 bitmap_nr = load_block_bitmap(sb, bitmap, block_group); 244 if (bitmap_nr < 0) 245 goto out; 246 bh = bitmap->s_block_bitmap[bitmap_nr]; 247 248 bit = block % (sb->s_blocksize << 3); 249 250 while (bit < (sb->s_blocksize << 3) && block_count > 0) 251 { 252 if (!udf_test_bit(bit, bh->b_data)) 253 goto out; 254 else if (DQUOT_PREALLOC_BLOCK(inode, 1)) 255 goto out; 256 else if (!udf_clear_bit(bit, bh->b_data)) 257 { 258 udf_debug("bit already cleared for block %d\n", bit); 259 DQUOT_FREE_BLOCK(inode, 1); 260 goto out; 261 } 262 block_count --; 263 alloc_count ++; 264 bit ++; 265 block ++; 266 } 267 mark_buffer_dirty(bh); 268 if (block_count > 0) 269 goto repeat; 270 out: 271 if (UDF_SB_LVIDBH(sb)) 272 { 273 UDF_SB_LVID(sb)->freeSpaceTable[partition] = 274 cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[partition])-alloc_count); 275 mark_buffer_dirty(UDF_SB_LVIDBH(sb)); 276 } 277 sb->s_dirt = 1; 278 mutex_unlock(&sbi->s_alloc_mutex); 279 return alloc_count; 280 } 281 282 static int udf_bitmap_new_block(struct super_block * sb, 283 struct inode * inode, 284 struct udf_bitmap *bitmap, uint16_t partition, uint32_t goal, int *err) 285 { 286 struct udf_sb_info *sbi = UDF_SB(sb); 287 int newbit, bit=0, block, block_group, group_start; 288 int end_goal, nr_groups, bitmap_nr, i; 289 struct buffer_head *bh = NULL; 290 char *ptr; 291 int newblock = 0; 292 293 *err = -ENOSPC; 294 mutex_lock(&sbi->s_alloc_mutex); 295 296 repeat: 297 if (goal < 0 || goal >= UDF_SB_PARTLEN(sb, partition)) 298 goal = 0; 299 300 nr_groups = bitmap->s_nr_groups; 301 block = goal + (sizeof(struct spaceBitmapDesc) << 3); 302 block_group = block >> (sb->s_blocksize_bits + 3); 303 group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc); 304 305 bitmap_nr = load_block_bitmap(sb, bitmap, block_group); 306 if (bitmap_nr < 0) 307 goto error_return; 308 bh = bitmap->s_block_bitmap[bitmap_nr]; 309 ptr = memscan((char *)bh->b_data + group_start, 0xFF, sb->s_blocksize - group_start); 310 311 if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) 312 { 313 bit = block % (sb->s_blocksize << 3); 314 315 if (udf_test_bit(bit, bh->b_data)) 316 { 317 goto got_block; 318 } 319 end_goal = (bit + 63) & ~63; 320 bit = udf_find_next_one_bit(bh->b_data, end_goal, bit); 321 if (bit < end_goal) 322 goto got_block; 323 ptr = memscan((char *)bh->b_data + (bit >> 3), 0xFF, sb->s_blocksize - ((bit + 7) >> 3)); 324 newbit = (ptr - ((char *)bh->b_data)) << 3; 325 if (newbit < sb->s_blocksize << 3) 326 { 327 bit = newbit; 328 goto search_back; 329 } 330 newbit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3, bit); 331 if (newbit < sb->s_blocksize << 3) 332 { 333 bit = newbit; 334 goto got_block; 335 } 336 } 337 338 for (i=0; i<(nr_groups*2); i++) 339 { 340 block_group ++; 341 if (block_group >= nr_groups) 342 block_group = 0; 343 group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc); 344 345 bitmap_nr = load_block_bitmap(sb, bitmap, block_group); 346 if (bitmap_nr < 0) 347 goto error_return; 348 bh = bitmap->s_block_bitmap[bitmap_nr]; 349 if (i < nr_groups) 350 { 351 ptr = memscan((char *)bh->b_data + group_start, 0xFF, sb->s_blocksize - group_start); 352 if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) 353 { 354 bit = (ptr - ((char *)bh->b_data)) << 3; 355 break; 356 } 357 } 358 else 359 { 360 bit = udf_find_next_one_bit((char *)bh->b_data, sb->s_blocksize << 3, group_start << 3); 361 if (bit < sb->s_blocksize << 3) 362 break; 363 } 364 } 365 if (i >= (nr_groups*2)) 366 { 367 mutex_unlock(&sbi->s_alloc_mutex); 368 return newblock; 369 } 370 if (bit < sb->s_blocksize << 3) 371 goto search_back; 372 else 373 bit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3, group_start << 3); 374 if (bit >= sb->s_blocksize << 3) 375 { 376 mutex_unlock(&sbi->s_alloc_mutex); 377 return 0; 378 } 379 380 search_back: 381 for (i=0; i<7 && bit > (group_start << 3) && udf_test_bit(bit - 1, bh->b_data); i++, bit--); 382 383 got_block: 384 385 /* 386 * Check quota for allocation of this block. 387 */ 388 if (inode && DQUOT_ALLOC_BLOCK(inode, 1)) 389 { 390 mutex_unlock(&sbi->s_alloc_mutex); 391 *err = -EDQUOT; 392 return 0; 393 } 394 395 newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) - 396 (sizeof(struct spaceBitmapDesc) << 3); 397 398 if (!udf_clear_bit(bit, bh->b_data)) 399 { 400 udf_debug("bit already cleared for block %d\n", bit); 401 goto repeat; 402 } 403 404 mark_buffer_dirty(bh); 405 406 if (UDF_SB_LVIDBH(sb)) 407 { 408 UDF_SB_LVID(sb)->freeSpaceTable[partition] = 409 cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[partition])-1); 410 mark_buffer_dirty(UDF_SB_LVIDBH(sb)); 411 } 412 sb->s_dirt = 1; 413 mutex_unlock(&sbi->s_alloc_mutex); 414 *err = 0; 415 return newblock; 416 417 error_return: 418 *err = -EIO; 419 mutex_unlock(&sbi->s_alloc_mutex); 420 return 0; 421 } 422 423 static void udf_table_free_blocks(struct super_block * sb, 424 struct inode * inode, 425 struct inode * table, 426 kernel_lb_addr bloc, uint32_t offset, uint32_t count) 427 { 428 struct udf_sb_info *sbi = UDF_SB(sb); 429 uint32_t start, end; 430 uint32_t elen; 431 kernel_lb_addr eloc; 432 struct extent_position oepos, epos; 433 int8_t etype; 434 int i; 435 436 mutex_lock(&sbi->s_alloc_mutex); 437 if (bloc.logicalBlockNum < 0 || 438 (bloc.logicalBlockNum + count) > UDF_SB_PARTLEN(sb, bloc.partitionReferenceNum)) 439 { 440 udf_debug("%d < %d || %d + %d > %d\n", 441 bloc.logicalBlockNum, 0, bloc.logicalBlockNum, count, 442 UDF_SB_PARTLEN(sb, bloc.partitionReferenceNum)); 443 goto error_return; 444 } 445 446 /* We do this up front - There are some error conditions that could occure, 447 but.. oh well */ 448 if (inode) 449 DQUOT_FREE_BLOCK(inode, count); 450 if (UDF_SB_LVIDBH(sb)) 451 { 452 UDF_SB_LVID(sb)->freeSpaceTable[UDF_SB_PARTITION(sb)] = 453 cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[UDF_SB_PARTITION(sb)])+count); 454 mark_buffer_dirty(UDF_SB_LVIDBH(sb)); 455 } 456 457 start = bloc.logicalBlockNum + offset; 458 end = bloc.logicalBlockNum + offset + count - 1; 459 460 epos.offset = oepos.offset = sizeof(struct unallocSpaceEntry); 461 elen = 0; 462 epos.block = oepos.block = UDF_I_LOCATION(table); 463 epos.bh = oepos.bh = NULL; 464 465 while (count && (etype = 466 udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) 467 { 468 if (((eloc.logicalBlockNum + (elen >> sb->s_blocksize_bits)) == 469 start)) 470 { 471 if ((0x3FFFFFFF - elen) < (count << sb->s_blocksize_bits)) 472 { 473 count -= ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits); 474 start += ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits); 475 elen = (etype << 30) | (0x40000000 - sb->s_blocksize); 476 } 477 else 478 { 479 elen = (etype << 30) | 480 (elen + (count << sb->s_blocksize_bits)); 481 start += count; 482 count = 0; 483 } 484 udf_write_aext(table, &oepos, eloc, elen, 1); 485 } 486 else if (eloc.logicalBlockNum == (end + 1)) 487 { 488 if ((0x3FFFFFFF - elen) < (count << sb->s_blocksize_bits)) 489 { 490 count -= ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits); 491 end -= ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits); 492 eloc.logicalBlockNum -= 493 ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits); 494 elen = (etype << 30) | (0x40000000 - sb->s_blocksize); 495 } 496 else 497 { 498 eloc.logicalBlockNum = start; 499 elen = (etype << 30) | 500 (elen + (count << sb->s_blocksize_bits)); 501 end -= count; 502 count = 0; 503 } 504 udf_write_aext(table, &oepos, eloc, elen, 1); 505 } 506 507 if (epos.bh != oepos.bh) 508 { 509 i = -1; 510 oepos.block = epos.block; 511 brelse(oepos.bh); 512 get_bh(epos.bh); 513 oepos.bh = epos.bh; 514 oepos.offset = 0; 515 } 516 else 517 oepos.offset = epos.offset; 518 } 519 520 if (count) 521 { 522 /* NOTE: we CANNOT use udf_add_aext here, as it can try to allocate 523 a new block, and since we hold the super block lock already 524 very bad things would happen :) 525 526 We copy the behavior of udf_add_aext, but instead of 527 trying to allocate a new block close to the existing one, 528 we just steal a block from the extent we are trying to add. 529 530 It would be nice if the blocks were close together, but it 531 isn't required. 532 */ 533 534 int adsize; 535 short_ad *sad = NULL; 536 long_ad *lad = NULL; 537 struct allocExtDesc *aed; 538 539 eloc.logicalBlockNum = start; 540 elen = EXT_RECORDED_ALLOCATED | 541 (count << sb->s_blocksize_bits); 542 543 if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_SHORT) 544 adsize = sizeof(short_ad); 545 else if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_LONG) 546 adsize = sizeof(long_ad); 547 else 548 { 549 brelse(oepos.bh); 550 brelse(epos.bh); 551 goto error_return; 552 } 553 554 if (epos.offset + (2 * adsize) > sb->s_blocksize) 555 { 556 char *sptr, *dptr; 557 int loffset; 558 559 brelse(oepos.bh); 560 oepos = epos; 561 562 /* Steal a block from the extent being free'd */ 563 epos.block.logicalBlockNum = eloc.logicalBlockNum; 564 eloc.logicalBlockNum ++; 565 elen -= sb->s_blocksize; 566 567 if (!(epos.bh = udf_tread(sb, 568 udf_get_lb_pblock(sb, epos.block, 0)))) 569 { 570 brelse(oepos.bh); 571 goto error_return; 572 } 573 aed = (struct allocExtDesc *)(epos.bh->b_data); 574 aed->previousAllocExtLocation = cpu_to_le32(oepos.block.logicalBlockNum); 575 if (epos.offset + adsize > sb->s_blocksize) 576 { 577 loffset = epos.offset; 578 aed->lengthAllocDescs = cpu_to_le32(adsize); 579 sptr = UDF_I_DATA(inode) + epos.offset - 580 udf_file_entry_alloc_offset(inode) + 581 UDF_I_LENEATTR(inode) - adsize; 582 dptr = epos.bh->b_data + sizeof(struct allocExtDesc); 583 memcpy(dptr, sptr, adsize); 584 epos.offset = sizeof(struct allocExtDesc) + adsize; 585 } 586 else 587 { 588 loffset = epos.offset + adsize; 589 aed->lengthAllocDescs = cpu_to_le32(0); 590 sptr = oepos.bh->b_data + epos.offset; 591 epos.offset = sizeof(struct allocExtDesc); 592 593 if (oepos.bh) 594 { 595 aed = (struct allocExtDesc *)oepos.bh->b_data; 596 aed->lengthAllocDescs = 597 cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) + adsize); 598 } 599 else 600 { 601 UDF_I_LENALLOC(table) += adsize; 602 mark_inode_dirty(table); 603 } 604 } 605 if (UDF_SB_UDFREV(sb) >= 0x0200) 606 udf_new_tag(epos.bh->b_data, TAG_IDENT_AED, 3, 1, 607 epos.block.logicalBlockNum, sizeof(tag)); 608 else 609 udf_new_tag(epos.bh->b_data, TAG_IDENT_AED, 2, 1, 610 epos.block.logicalBlockNum, sizeof(tag)); 611 switch (UDF_I_ALLOCTYPE(table)) 612 { 613 case ICBTAG_FLAG_AD_SHORT: 614 { 615 sad = (short_ad *)sptr; 616 sad->extLength = cpu_to_le32( 617 EXT_NEXT_EXTENT_ALLOCDECS | 618 sb->s_blocksize); 619 sad->extPosition = cpu_to_le32(epos.block.logicalBlockNum); 620 break; 621 } 622 case ICBTAG_FLAG_AD_LONG: 623 { 624 lad = (long_ad *)sptr; 625 lad->extLength = cpu_to_le32( 626 EXT_NEXT_EXTENT_ALLOCDECS | 627 sb->s_blocksize); 628 lad->extLocation = cpu_to_lelb(epos.block); 629 break; 630 } 631 } 632 if (oepos.bh) 633 { 634 udf_update_tag(oepos.bh->b_data, loffset); 635 mark_buffer_dirty(oepos.bh); 636 } 637 else 638 mark_inode_dirty(table); 639 } 640 641 if (elen) /* It's possible that stealing the block emptied the extent */ 642 { 643 udf_write_aext(table, &epos, eloc, elen, 1); 644 645 if (!epos.bh) 646 { 647 UDF_I_LENALLOC(table) += adsize; 648 mark_inode_dirty(table); 649 } 650 else 651 { 652 aed = (struct allocExtDesc *)epos.bh->b_data; 653 aed->lengthAllocDescs = 654 cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) + adsize); 655 udf_update_tag(epos.bh->b_data, epos.offset); 656 mark_buffer_dirty(epos.bh); 657 } 658 } 659 } 660 661 brelse(epos.bh); 662 brelse(oepos.bh); 663 664 error_return: 665 sb->s_dirt = 1; 666 mutex_unlock(&sbi->s_alloc_mutex); 667 return; 668 } 669 670 static int udf_table_prealloc_blocks(struct super_block * sb, 671 struct inode * inode, 672 struct inode *table, uint16_t partition, uint32_t first_block, 673 uint32_t block_count) 674 { 675 struct udf_sb_info *sbi = UDF_SB(sb); 676 int alloc_count = 0; 677 uint32_t elen, adsize; 678 kernel_lb_addr eloc; 679 struct extent_position epos; 680 int8_t etype = -1; 681 682 if (first_block < 0 || first_block >= UDF_SB_PARTLEN(sb, partition)) 683 return 0; 684 685 if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_SHORT) 686 adsize = sizeof(short_ad); 687 else if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_LONG) 688 adsize = sizeof(long_ad); 689 else 690 return 0; 691 692 mutex_lock(&sbi->s_alloc_mutex); 693 epos.offset = sizeof(struct unallocSpaceEntry); 694 epos.block = UDF_I_LOCATION(table); 695 epos.bh = NULL; 696 eloc.logicalBlockNum = 0xFFFFFFFF; 697 698 while (first_block != eloc.logicalBlockNum && (etype = 699 udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) 700 { 701 udf_debug("eloc=%d, elen=%d, first_block=%d\n", 702 eloc.logicalBlockNum, elen, first_block); 703 ; /* empty loop body */ 704 } 705 706 if (first_block == eloc.logicalBlockNum) 707 { 708 epos.offset -= adsize; 709 710 alloc_count = (elen >> sb->s_blocksize_bits); 711 if (inode && DQUOT_PREALLOC_BLOCK(inode, alloc_count > block_count ? block_count : alloc_count)) 712 alloc_count = 0; 713 else if (alloc_count > block_count) 714 { 715 alloc_count = block_count; 716 eloc.logicalBlockNum += alloc_count; 717 elen -= (alloc_count << sb->s_blocksize_bits); 718 udf_write_aext(table, &epos, eloc, (etype << 30) | elen, 1); 719 } 720 else 721 udf_delete_aext(table, epos, eloc, (etype << 30) | elen); 722 } 723 else 724 alloc_count = 0; 725 726 brelse(epos.bh); 727 728 if (alloc_count && UDF_SB_LVIDBH(sb)) 729 { 730 UDF_SB_LVID(sb)->freeSpaceTable[partition] = 731 cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[partition])-alloc_count); 732 mark_buffer_dirty(UDF_SB_LVIDBH(sb)); 733 sb->s_dirt = 1; 734 } 735 mutex_unlock(&sbi->s_alloc_mutex); 736 return alloc_count; 737 } 738 739 static int udf_table_new_block(struct super_block * sb, 740 struct inode * inode, 741 struct inode *table, uint16_t partition, uint32_t goal, int *err) 742 { 743 struct udf_sb_info *sbi = UDF_SB(sb); 744 uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF; 745 uint32_t newblock = 0, adsize; 746 uint32_t elen, goal_elen = 0; 747 kernel_lb_addr eloc, goal_eloc; 748 struct extent_position epos, goal_epos; 749 int8_t etype; 750 751 *err = -ENOSPC; 752 753 if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_SHORT) 754 adsize = sizeof(short_ad); 755 else if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_LONG) 756 adsize = sizeof(long_ad); 757 else 758 return newblock; 759 760 mutex_lock(&sbi->s_alloc_mutex); 761 if (goal < 0 || goal >= UDF_SB_PARTLEN(sb, partition)) 762 goal = 0; 763 764 /* We search for the closest matching block to goal. If we find a exact hit, 765 we stop. Otherwise we keep going till we run out of extents. 766 We store the buffer_head, bloc, and extoffset of the current closest 767 match and use that when we are done. 768 */ 769 epos.offset = sizeof(struct unallocSpaceEntry); 770 epos.block = UDF_I_LOCATION(table); 771 epos.bh = goal_epos.bh = NULL; 772 773 while (spread && (etype = 774 udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) 775 { 776 if (goal >= eloc.logicalBlockNum) 777 { 778 if (goal < eloc.logicalBlockNum + (elen >> sb->s_blocksize_bits)) 779 nspread = 0; 780 else 781 nspread = goal - eloc.logicalBlockNum - 782 (elen >> sb->s_blocksize_bits); 783 } 784 else 785 nspread = eloc.logicalBlockNum - goal; 786 787 if (nspread < spread) 788 { 789 spread = nspread; 790 if (goal_epos.bh != epos.bh) 791 { 792 brelse(goal_epos.bh); 793 goal_epos.bh = epos.bh; 794 get_bh(goal_epos.bh); 795 } 796 goal_epos.block = epos.block; 797 goal_epos.offset = epos.offset - adsize; 798 goal_eloc = eloc; 799 goal_elen = (etype << 30) | elen; 800 } 801 } 802 803 brelse(epos.bh); 804 805 if (spread == 0xFFFFFFFF) 806 { 807 brelse(goal_epos.bh); 808 mutex_unlock(&sbi->s_alloc_mutex); 809 return 0; 810 } 811 812 /* Only allocate blocks from the beginning of the extent. 813 That way, we only delete (empty) extents, never have to insert an 814 extent because of splitting */ 815 /* This works, but very poorly.... */ 816 817 newblock = goal_eloc.logicalBlockNum; 818 goal_eloc.logicalBlockNum ++; 819 goal_elen -= sb->s_blocksize; 820 821 if (inode && DQUOT_ALLOC_BLOCK(inode, 1)) 822 { 823 brelse(goal_epos.bh); 824 mutex_unlock(&sbi->s_alloc_mutex); 825 *err = -EDQUOT; 826 return 0; 827 } 828 829 if (goal_elen) 830 udf_write_aext(table, &goal_epos, goal_eloc, goal_elen, 1); 831 else 832 udf_delete_aext(table, goal_epos, goal_eloc, goal_elen); 833 brelse(goal_epos.bh); 834 835 if (UDF_SB_LVIDBH(sb)) 836 { 837 UDF_SB_LVID(sb)->freeSpaceTable[partition] = 838 cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[partition])-1); 839 mark_buffer_dirty(UDF_SB_LVIDBH(sb)); 840 } 841 842 sb->s_dirt = 1; 843 mutex_unlock(&sbi->s_alloc_mutex); 844 *err = 0; 845 return newblock; 846 } 847 848 inline void udf_free_blocks(struct super_block * sb, 849 struct inode * inode, 850 kernel_lb_addr bloc, uint32_t offset, uint32_t count) 851 { 852 uint16_t partition = bloc.partitionReferenceNum; 853 854 if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP) 855 { 856 return udf_bitmap_free_blocks(sb, inode, 857 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_bitmap, 858 bloc, offset, count); 859 } 860 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_TABLE) 861 { 862 return udf_table_free_blocks(sb, inode, 863 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_table, 864 bloc, offset, count); 865 } 866 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_BITMAP) 867 { 868 return udf_bitmap_free_blocks(sb, inode, 869 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_bitmap, 870 bloc, offset, count); 871 } 872 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_TABLE) 873 { 874 return udf_table_free_blocks(sb, inode, 875 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_table, 876 bloc, offset, count); 877 } 878 else 879 return; 880 } 881 882 inline int udf_prealloc_blocks(struct super_block * sb, 883 struct inode * inode, 884 uint16_t partition, uint32_t first_block, uint32_t block_count) 885 { 886 if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP) 887 { 888 return udf_bitmap_prealloc_blocks(sb, inode, 889 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_bitmap, 890 partition, first_block, block_count); 891 } 892 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_TABLE) 893 { 894 return udf_table_prealloc_blocks(sb, inode, 895 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_table, 896 partition, first_block, block_count); 897 } 898 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_BITMAP) 899 { 900 return udf_bitmap_prealloc_blocks(sb, inode, 901 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_bitmap, 902 partition, first_block, block_count); 903 } 904 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_TABLE) 905 { 906 return udf_table_prealloc_blocks(sb, inode, 907 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_table, 908 partition, first_block, block_count); 909 } 910 else 911 return 0; 912 } 913 914 inline int udf_new_block(struct super_block * sb, 915 struct inode * inode, 916 uint16_t partition, uint32_t goal, int *err) 917 { 918 int ret; 919 920 if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP) 921 { 922 ret = udf_bitmap_new_block(sb, inode, 923 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_bitmap, 924 partition, goal, err); 925 return ret; 926 } 927 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_TABLE) 928 { 929 return udf_table_new_block(sb, inode, 930 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_table, 931 partition, goal, err); 932 } 933 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_BITMAP) 934 { 935 return udf_bitmap_new_block(sb, inode, 936 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_bitmap, 937 partition, goal, err); 938 } 939 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_TABLE) 940 { 941 return udf_table_new_block(sb, inode, 942 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_table, 943 partition, goal, err); 944 } 945 else 946 { 947 *err = -EIO; 948 return 0; 949 } 950 } 951