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 down(&sbi->s_alloc_sem); 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 up(&sbi->s_alloc_sem); 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 down(&sbi->s_alloc_sem); 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 up(&sbi->s_alloc_sem); 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 down(&sbi->s_alloc_sem); 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 up(&sbi->s_alloc_sem); 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 up(&sbi->s_alloc_sem); 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 up(&sbi->s_alloc_sem); 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 up(&sbi->s_alloc_sem); 414 *err = 0; 415 return newblock; 416 417 error_return: 418 *err = -EIO; 419 up(&sbi->s_alloc_sem); 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 nextoffset, oextoffset, elen; 431 kernel_lb_addr nbloc, obloc, eloc; 432 struct buffer_head *obh, *nbh; 433 int8_t etype; 434 int i; 435 436 down(&sbi->s_alloc_sem); 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 oextoffset = nextoffset = sizeof(struct unallocSpaceEntry); 461 elen = 0; 462 obloc = nbloc = UDF_I_LOCATION(table); 463 464 obh = nbh = NULL; 465 466 while (count && (etype = 467 udf_next_aext(table, &nbloc, &nextoffset, &eloc, &elen, &nbh, 1)) != -1) 468 { 469 if (((eloc.logicalBlockNum + (elen >> sb->s_blocksize_bits)) == 470 start)) 471 { 472 if ((0x3FFFFFFF - elen) < (count << sb->s_blocksize_bits)) 473 { 474 count -= ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits); 475 start += ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits); 476 elen = (etype << 30) | (0x40000000 - sb->s_blocksize); 477 } 478 else 479 { 480 elen = (etype << 30) | 481 (elen + (count << sb->s_blocksize_bits)); 482 start += count; 483 count = 0; 484 } 485 udf_write_aext(table, obloc, &oextoffset, eloc, elen, obh, 1); 486 } 487 else if (eloc.logicalBlockNum == (end + 1)) 488 { 489 if ((0x3FFFFFFF - elen) < (count << sb->s_blocksize_bits)) 490 { 491 count -= ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits); 492 end -= ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits); 493 eloc.logicalBlockNum -= 494 ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits); 495 elen = (etype << 30) | (0x40000000 - sb->s_blocksize); 496 } 497 else 498 { 499 eloc.logicalBlockNum = start; 500 elen = (etype << 30) | 501 (elen + (count << sb->s_blocksize_bits)); 502 end -= count; 503 count = 0; 504 } 505 udf_write_aext(table, obloc, &oextoffset, eloc, elen, obh, 1); 506 } 507 508 if (nbh != obh) 509 { 510 i = -1; 511 obloc = nbloc; 512 udf_release_data(obh); 513 atomic_inc(&nbh->b_count); 514 obh = nbh; 515 oextoffset = 0; 516 } 517 else 518 oextoffset = nextoffset; 519 } 520 521 if (count) 522 { 523 /* NOTE: we CANNOT use udf_add_aext here, as it can try to allocate 524 a new block, and since we hold the super block lock already 525 very bad things would happen :) 526 527 We copy the behavior of udf_add_aext, but instead of 528 trying to allocate a new block close to the existing one, 529 we just steal a block from the extent we are trying to add. 530 531 It would be nice if the blocks were close together, but it 532 isn't required. 533 */ 534 535 int adsize; 536 short_ad *sad = NULL; 537 long_ad *lad = NULL; 538 struct allocExtDesc *aed; 539 540 eloc.logicalBlockNum = start; 541 elen = EXT_RECORDED_ALLOCATED | 542 (count << sb->s_blocksize_bits); 543 544 if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_SHORT) 545 adsize = sizeof(short_ad); 546 else if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_LONG) 547 adsize = sizeof(long_ad); 548 else 549 { 550 udf_release_data(obh); 551 udf_release_data(nbh); 552 goto error_return; 553 } 554 555 if (nextoffset + (2 * adsize) > sb->s_blocksize) 556 { 557 char *sptr, *dptr; 558 int loffset; 559 560 udf_release_data(obh); 561 obh = nbh; 562 obloc = nbloc; 563 oextoffset = nextoffset; 564 565 /* Steal a block from the extent being free'd */ 566 nbloc.logicalBlockNum = eloc.logicalBlockNum; 567 eloc.logicalBlockNum ++; 568 elen -= sb->s_blocksize; 569 570 if (!(nbh = udf_tread(sb, 571 udf_get_lb_pblock(sb, nbloc, 0)))) 572 { 573 udf_release_data(obh); 574 goto error_return; 575 } 576 aed = (struct allocExtDesc *)(nbh->b_data); 577 aed->previousAllocExtLocation = cpu_to_le32(obloc.logicalBlockNum); 578 if (nextoffset + adsize > sb->s_blocksize) 579 { 580 loffset = nextoffset; 581 aed->lengthAllocDescs = cpu_to_le32(adsize); 582 if (obh) 583 sptr = UDF_I_DATA(inode) + nextoffset - udf_file_entry_alloc_offset(inode) + UDF_I_LENEATTR(inode) - adsize; 584 else 585 sptr = obh->b_data + nextoffset - adsize; 586 dptr = nbh->b_data + sizeof(struct allocExtDesc); 587 memcpy(dptr, sptr, adsize); 588 nextoffset = sizeof(struct allocExtDesc) + adsize; 589 } 590 else 591 { 592 loffset = nextoffset + adsize; 593 aed->lengthAllocDescs = cpu_to_le32(0); 594 sptr = (obh)->b_data + nextoffset; 595 nextoffset = sizeof(struct allocExtDesc); 596 597 if (obh) 598 { 599 aed = (struct allocExtDesc *)(obh)->b_data; 600 aed->lengthAllocDescs = 601 cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) + adsize); 602 } 603 else 604 { 605 UDF_I_LENALLOC(table) += adsize; 606 mark_inode_dirty(table); 607 } 608 } 609 if (UDF_SB_UDFREV(sb) >= 0x0200) 610 udf_new_tag(nbh->b_data, TAG_IDENT_AED, 3, 1, 611 nbloc.logicalBlockNum, sizeof(tag)); 612 else 613 udf_new_tag(nbh->b_data, TAG_IDENT_AED, 2, 1, 614 nbloc.logicalBlockNum, sizeof(tag)); 615 switch (UDF_I_ALLOCTYPE(table)) 616 { 617 case ICBTAG_FLAG_AD_SHORT: 618 { 619 sad = (short_ad *)sptr; 620 sad->extLength = cpu_to_le32( 621 EXT_NEXT_EXTENT_ALLOCDECS | 622 sb->s_blocksize); 623 sad->extPosition = cpu_to_le32(nbloc.logicalBlockNum); 624 break; 625 } 626 case ICBTAG_FLAG_AD_LONG: 627 { 628 lad = (long_ad *)sptr; 629 lad->extLength = cpu_to_le32( 630 EXT_NEXT_EXTENT_ALLOCDECS | 631 sb->s_blocksize); 632 lad->extLocation = cpu_to_lelb(nbloc); 633 break; 634 } 635 } 636 if (obh) 637 { 638 udf_update_tag(obh->b_data, loffset); 639 mark_buffer_dirty(obh); 640 } 641 else 642 mark_inode_dirty(table); 643 } 644 645 if (elen) /* It's possible that stealing the block emptied the extent */ 646 { 647 udf_write_aext(table, nbloc, &nextoffset, eloc, elen, nbh, 1); 648 649 if (!nbh) 650 { 651 UDF_I_LENALLOC(table) += adsize; 652 mark_inode_dirty(table); 653 } 654 else 655 { 656 aed = (struct allocExtDesc *)nbh->b_data; 657 aed->lengthAllocDescs = 658 cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) + adsize); 659 udf_update_tag(nbh->b_data, nextoffset); 660 mark_buffer_dirty(nbh); 661 } 662 } 663 } 664 665 udf_release_data(nbh); 666 udf_release_data(obh); 667 668 error_return: 669 sb->s_dirt = 1; 670 up(&sbi->s_alloc_sem); 671 return; 672 } 673 674 static int udf_table_prealloc_blocks(struct super_block * sb, 675 struct inode * inode, 676 struct inode *table, uint16_t partition, uint32_t first_block, 677 uint32_t block_count) 678 { 679 struct udf_sb_info *sbi = UDF_SB(sb); 680 int alloc_count = 0; 681 uint32_t extoffset, elen, adsize; 682 kernel_lb_addr bloc, eloc; 683 struct buffer_head *bh; 684 int8_t etype = -1; 685 686 if (first_block < 0 || first_block >= UDF_SB_PARTLEN(sb, partition)) 687 return 0; 688 689 if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_SHORT) 690 adsize = sizeof(short_ad); 691 else if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_LONG) 692 adsize = sizeof(long_ad); 693 else 694 return 0; 695 696 down(&sbi->s_alloc_sem); 697 extoffset = sizeof(struct unallocSpaceEntry); 698 bloc = UDF_I_LOCATION(table); 699 700 bh = NULL; 701 eloc.logicalBlockNum = 0xFFFFFFFF; 702 703 while (first_block != eloc.logicalBlockNum && (etype = 704 udf_next_aext(table, &bloc, &extoffset, &eloc, &elen, &bh, 1)) != -1) 705 { 706 udf_debug("eloc=%d, elen=%d, first_block=%d\n", 707 eloc.logicalBlockNum, elen, first_block); 708 ; /* empty loop body */ 709 } 710 711 if (first_block == eloc.logicalBlockNum) 712 { 713 extoffset -= adsize; 714 715 alloc_count = (elen >> sb->s_blocksize_bits); 716 if (inode && DQUOT_PREALLOC_BLOCK(inode, alloc_count > block_count ? block_count : alloc_count)) 717 alloc_count = 0; 718 else if (alloc_count > block_count) 719 { 720 alloc_count = block_count; 721 eloc.logicalBlockNum += alloc_count; 722 elen -= (alloc_count << sb->s_blocksize_bits); 723 udf_write_aext(table, bloc, &extoffset, eloc, (etype << 30) | elen, bh, 1); 724 } 725 else 726 udf_delete_aext(table, bloc, extoffset, eloc, (etype << 30) | elen, bh); 727 } 728 else 729 alloc_count = 0; 730 731 udf_release_data(bh); 732 733 if (alloc_count && UDF_SB_LVIDBH(sb)) 734 { 735 UDF_SB_LVID(sb)->freeSpaceTable[partition] = 736 cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[partition])-alloc_count); 737 mark_buffer_dirty(UDF_SB_LVIDBH(sb)); 738 sb->s_dirt = 1; 739 } 740 up(&sbi->s_alloc_sem); 741 return alloc_count; 742 } 743 744 static int udf_table_new_block(struct super_block * sb, 745 struct inode * inode, 746 struct inode *table, uint16_t partition, uint32_t goal, int *err) 747 { 748 struct udf_sb_info *sbi = UDF_SB(sb); 749 uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF; 750 uint32_t newblock = 0, adsize; 751 uint32_t extoffset, goal_extoffset, elen, goal_elen = 0; 752 kernel_lb_addr bloc, goal_bloc, eloc, goal_eloc; 753 struct buffer_head *bh, *goal_bh; 754 int8_t etype; 755 756 *err = -ENOSPC; 757 758 if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_SHORT) 759 adsize = sizeof(short_ad); 760 else if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_LONG) 761 adsize = sizeof(long_ad); 762 else 763 return newblock; 764 765 down(&sbi->s_alloc_sem); 766 if (goal < 0 || goal >= UDF_SB_PARTLEN(sb, partition)) 767 goal = 0; 768 769 /* We search for the closest matching block to goal. If we find a exact hit, 770 we stop. Otherwise we keep going till we run out of extents. 771 We store the buffer_head, bloc, and extoffset of the current closest 772 match and use that when we are done. 773 */ 774 775 extoffset = sizeof(struct unallocSpaceEntry); 776 bloc = UDF_I_LOCATION(table); 777 778 goal_bh = bh = NULL; 779 780 while (spread && (etype = 781 udf_next_aext(table, &bloc, &extoffset, &eloc, &elen, &bh, 1)) != -1) 782 { 783 if (goal >= eloc.logicalBlockNum) 784 { 785 if (goal < eloc.logicalBlockNum + (elen >> sb->s_blocksize_bits)) 786 nspread = 0; 787 else 788 nspread = goal - eloc.logicalBlockNum - 789 (elen >> sb->s_blocksize_bits); 790 } 791 else 792 nspread = eloc.logicalBlockNum - goal; 793 794 if (nspread < spread) 795 { 796 spread = nspread; 797 if (goal_bh != bh) 798 { 799 udf_release_data(goal_bh); 800 goal_bh = bh; 801 atomic_inc(&goal_bh->b_count); 802 } 803 goal_bloc = bloc; 804 goal_extoffset = extoffset - adsize; 805 goal_eloc = eloc; 806 goal_elen = (etype << 30) | elen; 807 } 808 } 809 810 udf_release_data(bh); 811 812 if (spread == 0xFFFFFFFF) 813 { 814 udf_release_data(goal_bh); 815 up(&sbi->s_alloc_sem); 816 return 0; 817 } 818 819 /* Only allocate blocks from the beginning of the extent. 820 That way, we only delete (empty) extents, never have to insert an 821 extent because of splitting */ 822 /* This works, but very poorly.... */ 823 824 newblock = goal_eloc.logicalBlockNum; 825 goal_eloc.logicalBlockNum ++; 826 goal_elen -= sb->s_blocksize; 827 828 if (inode && DQUOT_ALLOC_BLOCK(inode, 1)) 829 { 830 udf_release_data(goal_bh); 831 up(&sbi->s_alloc_sem); 832 *err = -EDQUOT; 833 return 0; 834 } 835 836 if (goal_elen) 837 udf_write_aext(table, goal_bloc, &goal_extoffset, goal_eloc, goal_elen, goal_bh, 1); 838 else 839 udf_delete_aext(table, goal_bloc, goal_extoffset, goal_eloc, goal_elen, goal_bh); 840 udf_release_data(goal_bh); 841 842 if (UDF_SB_LVIDBH(sb)) 843 { 844 UDF_SB_LVID(sb)->freeSpaceTable[partition] = 845 cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[partition])-1); 846 mark_buffer_dirty(UDF_SB_LVIDBH(sb)); 847 } 848 849 sb->s_dirt = 1; 850 up(&sbi->s_alloc_sem); 851 *err = 0; 852 return newblock; 853 } 854 855 inline void udf_free_blocks(struct super_block * sb, 856 struct inode * inode, 857 kernel_lb_addr bloc, uint32_t offset, uint32_t count) 858 { 859 uint16_t partition = bloc.partitionReferenceNum; 860 861 if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP) 862 { 863 return udf_bitmap_free_blocks(sb, inode, 864 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_bitmap, 865 bloc, offset, count); 866 } 867 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_TABLE) 868 { 869 return udf_table_free_blocks(sb, inode, 870 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_table, 871 bloc, offset, count); 872 } 873 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_BITMAP) 874 { 875 return udf_bitmap_free_blocks(sb, inode, 876 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_bitmap, 877 bloc, offset, count); 878 } 879 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_TABLE) 880 { 881 return udf_table_free_blocks(sb, inode, 882 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_table, 883 bloc, offset, count); 884 } 885 else 886 return; 887 } 888 889 inline int udf_prealloc_blocks(struct super_block * sb, 890 struct inode * inode, 891 uint16_t partition, uint32_t first_block, uint32_t block_count) 892 { 893 if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP) 894 { 895 return udf_bitmap_prealloc_blocks(sb, inode, 896 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_bitmap, 897 partition, first_block, block_count); 898 } 899 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_TABLE) 900 { 901 return udf_table_prealloc_blocks(sb, inode, 902 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_table, 903 partition, first_block, block_count); 904 } 905 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_BITMAP) 906 { 907 return udf_bitmap_prealloc_blocks(sb, inode, 908 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_bitmap, 909 partition, first_block, block_count); 910 } 911 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_TABLE) 912 { 913 return udf_table_prealloc_blocks(sb, inode, 914 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_table, 915 partition, first_block, block_count); 916 } 917 else 918 return 0; 919 } 920 921 inline int udf_new_block(struct super_block * sb, 922 struct inode * inode, 923 uint16_t partition, uint32_t goal, int *err) 924 { 925 if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP) 926 { 927 return udf_bitmap_new_block(sb, inode, 928 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_bitmap, 929 partition, goal, err); 930 } 931 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_TABLE) 932 { 933 return udf_table_new_block(sb, inode, 934 UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_table, 935 partition, goal, err); 936 } 937 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_BITMAP) 938 { 939 return udf_bitmap_new_block(sb, inode, 940 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_bitmap, 941 partition, goal, err); 942 } 943 else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_TABLE) 944 { 945 return udf_table_new_block(sb, inode, 946 UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_table, 947 partition, goal, err); 948 } 949 else 950 { 951 *err = -EIO; 952 return 0; 953 } 954 } 955