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