| 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/buffer_head.h> |
| 25 | #include <linux/bitops.h> |
| 26 | |
| 27 | #include "udf_i.h" |
| 28 | #include "udf_sb.h" |
| 29 | |
| 30 | #define udf_clear_bit __test_and_clear_bit_le |
| 31 | #define udf_set_bit __test_and_set_bit_le |
| 32 | #define udf_test_bit test_bit_le |
| 33 | #define udf_find_next_one_bit find_next_bit_le |
| 34 | |
| 35 | static int read_block_bitmap(struct super_block *sb, |
| 36 | struct udf_bitmap *bitmap, unsigned int block, |
| 37 | unsigned long bitmap_nr) |
| 38 | { |
| 39 | struct buffer_head *bh = NULL; |
| 40 | int retval = 0; |
| 41 | struct kernel_lb_addr loc; |
| 42 | |
| 43 | loc.logicalBlockNum = bitmap->s_extPosition; |
| 44 | loc.partitionReferenceNum = UDF_SB(sb)->s_partition; |
| 45 | |
| 46 | bh = udf_tread(sb, udf_get_lb_pblock(sb, &loc, block)); |
| 47 | if (!bh) |
| 48 | retval = -EIO; |
| 49 | |
| 50 | bitmap->s_block_bitmap[bitmap_nr] = bh; |
| 51 | return retval; |
| 52 | } |
| 53 | |
| 54 | static int __load_block_bitmap(struct super_block *sb, |
| 55 | struct udf_bitmap *bitmap, |
| 56 | unsigned int block_group) |
| 57 | { |
| 58 | int retval = 0; |
| 59 | int nr_groups = bitmap->s_nr_groups; |
| 60 | |
| 61 | if (block_group >= nr_groups) { |
| 62 | udf_debug("block_group (%d) > nr_groups (%d)\n", |
| 63 | block_group, nr_groups); |
| 64 | } |
| 65 | |
| 66 | if (bitmap->s_block_bitmap[block_group]) { |
| 67 | return block_group; |
| 68 | } else { |
| 69 | retval = read_block_bitmap(sb, bitmap, block_group, |
| 70 | block_group); |
| 71 | if (retval < 0) |
| 72 | return retval; |
| 73 | return block_group; |
| 74 | } |
| 75 | } |
| 76 | |
| 77 | static inline int load_block_bitmap(struct super_block *sb, |
| 78 | struct udf_bitmap *bitmap, |
| 79 | unsigned int block_group) |
| 80 | { |
| 81 | int slot; |
| 82 | |
| 83 | slot = __load_block_bitmap(sb, bitmap, block_group); |
| 84 | |
| 85 | if (slot < 0) |
| 86 | return slot; |
| 87 | |
| 88 | if (!bitmap->s_block_bitmap[slot]) |
| 89 | return -EIO; |
| 90 | |
| 91 | return slot; |
| 92 | } |
| 93 | |
| 94 | static void udf_add_free_space(struct super_block *sb, u16 partition, u32 cnt) |
| 95 | { |
| 96 | struct udf_sb_info *sbi = UDF_SB(sb); |
| 97 | struct logicalVolIntegrityDesc *lvid; |
| 98 | |
| 99 | if (!sbi->s_lvid_bh) |
| 100 | return; |
| 101 | |
| 102 | lvid = (struct logicalVolIntegrityDesc *)sbi->s_lvid_bh->b_data; |
| 103 | le32_add_cpu(&lvid->freeSpaceTable[partition], cnt); |
| 104 | udf_updated_lvid(sb); |
| 105 | } |
| 106 | |
| 107 | static void udf_bitmap_free_blocks(struct super_block *sb, |
| 108 | struct udf_bitmap *bitmap, |
| 109 | struct kernel_lb_addr *bloc, |
| 110 | uint32_t offset, |
| 111 | uint32_t count) |
| 112 | { |
| 113 | struct udf_sb_info *sbi = UDF_SB(sb); |
| 114 | struct buffer_head *bh = NULL; |
| 115 | struct udf_part_map *partmap; |
| 116 | unsigned long block; |
| 117 | unsigned long block_group; |
| 118 | unsigned long bit; |
| 119 | unsigned long i; |
| 120 | int bitmap_nr; |
| 121 | unsigned long overflow; |
| 122 | |
| 123 | mutex_lock(&sbi->s_alloc_mutex); |
| 124 | partmap = &sbi->s_partmaps[bloc->partitionReferenceNum]; |
| 125 | if (bloc->logicalBlockNum + count < count || |
| 126 | (bloc->logicalBlockNum + count) > partmap->s_partition_len) { |
| 127 | udf_debug("%d < %d || %d + %d > %d\n", |
| 128 | bloc->logicalBlockNum, 0, |
| 129 | bloc->logicalBlockNum, count, |
| 130 | partmap->s_partition_len); |
| 131 | goto error_return; |
| 132 | } |
| 133 | |
| 134 | block = bloc->logicalBlockNum + offset + |
| 135 | (sizeof(struct spaceBitmapDesc) << 3); |
| 136 | |
| 137 | do { |
| 138 | overflow = 0; |
| 139 | block_group = block >> (sb->s_blocksize_bits + 3); |
| 140 | bit = block % (sb->s_blocksize << 3); |
| 141 | |
| 142 | /* |
| 143 | * Check to see if we are freeing blocks across a group boundary. |
| 144 | */ |
| 145 | if (bit + count > (sb->s_blocksize << 3)) { |
| 146 | overflow = bit + count - (sb->s_blocksize << 3); |
| 147 | count -= overflow; |
| 148 | } |
| 149 | bitmap_nr = load_block_bitmap(sb, bitmap, block_group); |
| 150 | if (bitmap_nr < 0) |
| 151 | goto error_return; |
| 152 | |
| 153 | bh = bitmap->s_block_bitmap[bitmap_nr]; |
| 154 | for (i = 0; i < count; i++) { |
| 155 | if (udf_set_bit(bit + i, bh->b_data)) { |
| 156 | udf_debug("bit %ld already set\n", bit + i); |
| 157 | udf_debug("byte=%2x\n", |
| 158 | ((char *)bh->b_data)[(bit + i) >> 3]); |
| 159 | } |
| 160 | } |
| 161 | udf_add_free_space(sb, sbi->s_partition, count); |
| 162 | mark_buffer_dirty(bh); |
| 163 | if (overflow) { |
| 164 | block += count; |
| 165 | count = overflow; |
| 166 | } |
| 167 | } while (overflow); |
| 168 | |
| 169 | error_return: |
| 170 | mutex_unlock(&sbi->s_alloc_mutex); |
| 171 | } |
| 172 | |
| 173 | static int udf_bitmap_prealloc_blocks(struct super_block *sb, |
| 174 | struct udf_bitmap *bitmap, |
| 175 | uint16_t partition, uint32_t first_block, |
| 176 | uint32_t block_count) |
| 177 | { |
| 178 | struct udf_sb_info *sbi = UDF_SB(sb); |
| 179 | int alloc_count = 0; |
| 180 | int bit, block, block_group, group_start; |
| 181 | int nr_groups, bitmap_nr; |
| 182 | struct buffer_head *bh; |
| 183 | __u32 part_len; |
| 184 | |
| 185 | mutex_lock(&sbi->s_alloc_mutex); |
| 186 | part_len = sbi->s_partmaps[partition].s_partition_len; |
| 187 | if (first_block >= part_len) |
| 188 | goto out; |
| 189 | |
| 190 | if (first_block + block_count > part_len) |
| 191 | block_count = part_len - first_block; |
| 192 | |
| 193 | do { |
| 194 | nr_groups = udf_compute_nr_groups(sb, partition); |
| 195 | block = first_block + (sizeof(struct spaceBitmapDesc) << 3); |
| 196 | block_group = block >> (sb->s_blocksize_bits + 3); |
| 197 | group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc); |
| 198 | |
| 199 | bitmap_nr = load_block_bitmap(sb, bitmap, block_group); |
| 200 | if (bitmap_nr < 0) |
| 201 | goto out; |
| 202 | bh = bitmap->s_block_bitmap[bitmap_nr]; |
| 203 | |
| 204 | bit = block % (sb->s_blocksize << 3); |
| 205 | |
| 206 | while (bit < (sb->s_blocksize << 3) && block_count > 0) { |
| 207 | if (!udf_clear_bit(bit, bh->b_data)) |
| 208 | goto out; |
| 209 | block_count--; |
| 210 | alloc_count++; |
| 211 | bit++; |
| 212 | block++; |
| 213 | } |
| 214 | mark_buffer_dirty(bh); |
| 215 | } while (block_count > 0); |
| 216 | |
| 217 | out: |
| 218 | udf_add_free_space(sb, partition, -alloc_count); |
| 219 | mutex_unlock(&sbi->s_alloc_mutex); |
| 220 | return alloc_count; |
| 221 | } |
| 222 | |
| 223 | static int udf_bitmap_new_block(struct super_block *sb, |
| 224 | struct udf_bitmap *bitmap, uint16_t partition, |
| 225 | uint32_t goal, int *err) |
| 226 | { |
| 227 | struct udf_sb_info *sbi = UDF_SB(sb); |
| 228 | int newbit, bit = 0, block, block_group, group_start; |
| 229 | int end_goal, nr_groups, bitmap_nr, i; |
| 230 | struct buffer_head *bh = NULL; |
| 231 | char *ptr; |
| 232 | int newblock = 0; |
| 233 | |
| 234 | *err = -ENOSPC; |
| 235 | mutex_lock(&sbi->s_alloc_mutex); |
| 236 | |
| 237 | repeat: |
| 238 | if (goal >= sbi->s_partmaps[partition].s_partition_len) |
| 239 | goal = 0; |
| 240 | |
| 241 | nr_groups = bitmap->s_nr_groups; |
| 242 | block = goal + (sizeof(struct spaceBitmapDesc) << 3); |
| 243 | block_group = block >> (sb->s_blocksize_bits + 3); |
| 244 | group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc); |
| 245 | |
| 246 | bitmap_nr = load_block_bitmap(sb, bitmap, block_group); |
| 247 | if (bitmap_nr < 0) |
| 248 | goto error_return; |
| 249 | bh = bitmap->s_block_bitmap[bitmap_nr]; |
| 250 | ptr = memscan((char *)bh->b_data + group_start, 0xFF, |
| 251 | sb->s_blocksize - group_start); |
| 252 | |
| 253 | if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) { |
| 254 | bit = block % (sb->s_blocksize << 3); |
| 255 | if (udf_test_bit(bit, bh->b_data)) |
| 256 | goto got_block; |
| 257 | |
| 258 | end_goal = (bit + 63) & ~63; |
| 259 | bit = udf_find_next_one_bit(bh->b_data, end_goal, bit); |
| 260 | if (bit < end_goal) |
| 261 | goto got_block; |
| 262 | |
| 263 | ptr = memscan((char *)bh->b_data + (bit >> 3), 0xFF, |
| 264 | sb->s_blocksize - ((bit + 7) >> 3)); |
| 265 | newbit = (ptr - ((char *)bh->b_data)) << 3; |
| 266 | if (newbit < sb->s_blocksize << 3) { |
| 267 | bit = newbit; |
| 268 | goto search_back; |
| 269 | } |
| 270 | |
| 271 | newbit = udf_find_next_one_bit(bh->b_data, |
| 272 | sb->s_blocksize << 3, bit); |
| 273 | if (newbit < sb->s_blocksize << 3) { |
| 274 | bit = newbit; |
| 275 | goto got_block; |
| 276 | } |
| 277 | } |
| 278 | |
| 279 | for (i = 0; i < (nr_groups * 2); i++) { |
| 280 | block_group++; |
| 281 | if (block_group >= nr_groups) |
| 282 | block_group = 0; |
| 283 | group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc); |
| 284 | |
| 285 | bitmap_nr = load_block_bitmap(sb, bitmap, block_group); |
| 286 | if (bitmap_nr < 0) |
| 287 | goto error_return; |
| 288 | bh = bitmap->s_block_bitmap[bitmap_nr]; |
| 289 | if (i < nr_groups) { |
| 290 | ptr = memscan((char *)bh->b_data + group_start, 0xFF, |
| 291 | sb->s_blocksize - group_start); |
| 292 | if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) { |
| 293 | bit = (ptr - ((char *)bh->b_data)) << 3; |
| 294 | break; |
| 295 | } |
| 296 | } else { |
| 297 | bit = udf_find_next_one_bit(bh->b_data, |
| 298 | sb->s_blocksize << 3, |
| 299 | group_start << 3); |
| 300 | if (bit < sb->s_blocksize << 3) |
| 301 | break; |
| 302 | } |
| 303 | } |
| 304 | if (i >= (nr_groups * 2)) { |
| 305 | mutex_unlock(&sbi->s_alloc_mutex); |
| 306 | return newblock; |
| 307 | } |
| 308 | if (bit < sb->s_blocksize << 3) |
| 309 | goto search_back; |
| 310 | else |
| 311 | bit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3, |
| 312 | group_start << 3); |
| 313 | if (bit >= sb->s_blocksize << 3) { |
| 314 | mutex_unlock(&sbi->s_alloc_mutex); |
| 315 | return 0; |
| 316 | } |
| 317 | |
| 318 | search_back: |
| 319 | i = 0; |
| 320 | while (i < 7 && bit > (group_start << 3) && |
| 321 | udf_test_bit(bit - 1, bh->b_data)) { |
| 322 | ++i; |
| 323 | --bit; |
| 324 | } |
| 325 | |
| 326 | got_block: |
| 327 | newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) - |
| 328 | (sizeof(struct spaceBitmapDesc) << 3); |
| 329 | |
| 330 | if (!udf_clear_bit(bit, bh->b_data)) { |
| 331 | udf_debug("bit already cleared for block %d\n", bit); |
| 332 | goto repeat; |
| 333 | } |
| 334 | |
| 335 | mark_buffer_dirty(bh); |
| 336 | |
| 337 | udf_add_free_space(sb, partition, -1); |
| 338 | mutex_unlock(&sbi->s_alloc_mutex); |
| 339 | *err = 0; |
| 340 | return newblock; |
| 341 | |
| 342 | error_return: |
| 343 | *err = -EIO; |
| 344 | mutex_unlock(&sbi->s_alloc_mutex); |
| 345 | return 0; |
| 346 | } |
| 347 | |
| 348 | static void udf_table_free_blocks(struct super_block *sb, |
| 349 | struct inode *table, |
| 350 | struct kernel_lb_addr *bloc, |
| 351 | uint32_t offset, |
| 352 | uint32_t count) |
| 353 | { |
| 354 | struct udf_sb_info *sbi = UDF_SB(sb); |
| 355 | struct udf_part_map *partmap; |
| 356 | uint32_t start, end; |
| 357 | uint32_t elen; |
| 358 | struct kernel_lb_addr eloc; |
| 359 | struct extent_position oepos, epos; |
| 360 | int8_t etype; |
| 361 | int i; |
| 362 | struct udf_inode_info *iinfo; |
| 363 | |
| 364 | mutex_lock(&sbi->s_alloc_mutex); |
| 365 | partmap = &sbi->s_partmaps[bloc->partitionReferenceNum]; |
| 366 | if (bloc->logicalBlockNum + count < count || |
| 367 | (bloc->logicalBlockNum + count) > partmap->s_partition_len) { |
| 368 | udf_debug("%d < %d || %d + %d > %d\n", |
| 369 | bloc->logicalBlockNum, 0, |
| 370 | bloc->logicalBlockNum, count, |
| 371 | partmap->s_partition_len); |
| 372 | goto error_return; |
| 373 | } |
| 374 | |
| 375 | iinfo = UDF_I(table); |
| 376 | udf_add_free_space(sb, sbi->s_partition, count); |
| 377 | |
| 378 | start = bloc->logicalBlockNum + offset; |
| 379 | end = bloc->logicalBlockNum + offset + count - 1; |
| 380 | |
| 381 | epos.offset = oepos.offset = sizeof(struct unallocSpaceEntry); |
| 382 | elen = 0; |
| 383 | epos.block = oepos.block = iinfo->i_location; |
| 384 | epos.bh = oepos.bh = NULL; |
| 385 | |
| 386 | while (count && |
| 387 | (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) { |
| 388 | if (((eloc.logicalBlockNum + |
| 389 | (elen >> sb->s_blocksize_bits)) == start)) { |
| 390 | if ((0x3FFFFFFF - elen) < |
| 391 | (count << sb->s_blocksize_bits)) { |
| 392 | uint32_t tmp = ((0x3FFFFFFF - elen) >> |
| 393 | sb->s_blocksize_bits); |
| 394 | count -= tmp; |
| 395 | start += tmp; |
| 396 | elen = (etype << 30) | |
| 397 | (0x40000000 - sb->s_blocksize); |
| 398 | } else { |
| 399 | elen = (etype << 30) | |
| 400 | (elen + |
| 401 | (count << sb->s_blocksize_bits)); |
| 402 | start += count; |
| 403 | count = 0; |
| 404 | } |
| 405 | udf_write_aext(table, &oepos, &eloc, elen, 1); |
| 406 | } else if (eloc.logicalBlockNum == (end + 1)) { |
| 407 | if ((0x3FFFFFFF - elen) < |
| 408 | (count << sb->s_blocksize_bits)) { |
| 409 | uint32_t tmp = ((0x3FFFFFFF - elen) >> |
| 410 | sb->s_blocksize_bits); |
| 411 | count -= tmp; |
| 412 | end -= tmp; |
| 413 | eloc.logicalBlockNum -= tmp; |
| 414 | elen = (etype << 30) | |
| 415 | (0x40000000 - sb->s_blocksize); |
| 416 | } else { |
| 417 | eloc.logicalBlockNum = start; |
| 418 | elen = (etype << 30) | |
| 419 | (elen + |
| 420 | (count << sb->s_blocksize_bits)); |
| 421 | end -= count; |
| 422 | count = 0; |
| 423 | } |
| 424 | udf_write_aext(table, &oepos, &eloc, elen, 1); |
| 425 | } |
| 426 | |
| 427 | if (epos.bh != oepos.bh) { |
| 428 | i = -1; |
| 429 | oepos.block = epos.block; |
| 430 | brelse(oepos.bh); |
| 431 | get_bh(epos.bh); |
| 432 | oepos.bh = epos.bh; |
| 433 | oepos.offset = 0; |
| 434 | } else { |
| 435 | oepos.offset = epos.offset; |
| 436 | } |
| 437 | } |
| 438 | |
| 439 | if (count) { |
| 440 | /* |
| 441 | * NOTE: we CANNOT use udf_add_aext here, as it can try to |
| 442 | * allocate a new block, and since we hold the super block |
| 443 | * lock already very bad things would happen :) |
| 444 | * |
| 445 | * We copy the behavior of udf_add_aext, but instead of |
| 446 | * trying to allocate a new block close to the existing one, |
| 447 | * we just steal a block from the extent we are trying to add. |
| 448 | * |
| 449 | * It would be nice if the blocks were close together, but it |
| 450 | * isn't required. |
| 451 | */ |
| 452 | |
| 453 | int adsize; |
| 454 | struct short_ad *sad = NULL; |
| 455 | struct long_ad *lad = NULL; |
| 456 | struct allocExtDesc *aed; |
| 457 | |
| 458 | eloc.logicalBlockNum = start; |
| 459 | elen = EXT_RECORDED_ALLOCATED | |
| 460 | (count << sb->s_blocksize_bits); |
| 461 | |
| 462 | if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT) |
| 463 | adsize = sizeof(struct short_ad); |
| 464 | else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG) |
| 465 | adsize = sizeof(struct long_ad); |
| 466 | else { |
| 467 | brelse(oepos.bh); |
| 468 | brelse(epos.bh); |
| 469 | goto error_return; |
| 470 | } |
| 471 | |
| 472 | if (epos.offset + (2 * adsize) > sb->s_blocksize) { |
| 473 | unsigned char *sptr, *dptr; |
| 474 | int loffset; |
| 475 | |
| 476 | brelse(oepos.bh); |
| 477 | oepos = epos; |
| 478 | |
| 479 | /* Steal a block from the extent being free'd */ |
| 480 | epos.block.logicalBlockNum = eloc.logicalBlockNum; |
| 481 | eloc.logicalBlockNum++; |
| 482 | elen -= sb->s_blocksize; |
| 483 | |
| 484 | epos.bh = udf_tread(sb, |
| 485 | udf_get_lb_pblock(sb, &epos.block, 0)); |
| 486 | if (!epos.bh) { |
| 487 | brelse(oepos.bh); |
| 488 | goto error_return; |
| 489 | } |
| 490 | aed = (struct allocExtDesc *)(epos.bh->b_data); |
| 491 | aed->previousAllocExtLocation = |
| 492 | cpu_to_le32(oepos.block.logicalBlockNum); |
| 493 | if (epos.offset + adsize > sb->s_blocksize) { |
| 494 | loffset = epos.offset; |
| 495 | aed->lengthAllocDescs = cpu_to_le32(adsize); |
| 496 | sptr = iinfo->i_ext.i_data + epos.offset |
| 497 | - adsize; |
| 498 | dptr = epos.bh->b_data + |
| 499 | sizeof(struct allocExtDesc); |
| 500 | memcpy(dptr, sptr, adsize); |
| 501 | epos.offset = sizeof(struct allocExtDesc) + |
| 502 | adsize; |
| 503 | } else { |
| 504 | loffset = epos.offset + adsize; |
| 505 | aed->lengthAllocDescs = cpu_to_le32(0); |
| 506 | if (oepos.bh) { |
| 507 | sptr = oepos.bh->b_data + epos.offset; |
| 508 | aed = (struct allocExtDesc *) |
| 509 | oepos.bh->b_data; |
| 510 | le32_add_cpu(&aed->lengthAllocDescs, |
| 511 | adsize); |
| 512 | } else { |
| 513 | sptr = iinfo->i_ext.i_data + |
| 514 | epos.offset; |
| 515 | iinfo->i_lenAlloc += adsize; |
| 516 | mark_inode_dirty(table); |
| 517 | } |
| 518 | epos.offset = sizeof(struct allocExtDesc); |
| 519 | } |
| 520 | if (sbi->s_udfrev >= 0x0200) |
| 521 | udf_new_tag(epos.bh->b_data, TAG_IDENT_AED, |
| 522 | 3, 1, epos.block.logicalBlockNum, |
| 523 | sizeof(struct tag)); |
| 524 | else |
| 525 | udf_new_tag(epos.bh->b_data, TAG_IDENT_AED, |
| 526 | 2, 1, epos.block.logicalBlockNum, |
| 527 | sizeof(struct tag)); |
| 528 | |
| 529 | switch (iinfo->i_alloc_type) { |
| 530 | case ICBTAG_FLAG_AD_SHORT: |
| 531 | sad = (struct short_ad *)sptr; |
| 532 | sad->extLength = cpu_to_le32( |
| 533 | EXT_NEXT_EXTENT_ALLOCDECS | |
| 534 | sb->s_blocksize); |
| 535 | sad->extPosition = |
| 536 | cpu_to_le32(epos.block.logicalBlockNum); |
| 537 | break; |
| 538 | case ICBTAG_FLAG_AD_LONG: |
| 539 | lad = (struct long_ad *)sptr; |
| 540 | lad->extLength = cpu_to_le32( |
| 541 | EXT_NEXT_EXTENT_ALLOCDECS | |
| 542 | sb->s_blocksize); |
| 543 | lad->extLocation = |
| 544 | cpu_to_lelb(epos.block); |
| 545 | break; |
| 546 | } |
| 547 | if (oepos.bh) { |
| 548 | udf_update_tag(oepos.bh->b_data, loffset); |
| 549 | mark_buffer_dirty(oepos.bh); |
| 550 | } else { |
| 551 | mark_inode_dirty(table); |
| 552 | } |
| 553 | } |
| 554 | |
| 555 | /* It's possible that stealing the block emptied the extent */ |
| 556 | if (elen) { |
| 557 | udf_write_aext(table, &epos, &eloc, elen, 1); |
| 558 | |
| 559 | if (!epos.bh) { |
| 560 | iinfo->i_lenAlloc += adsize; |
| 561 | mark_inode_dirty(table); |
| 562 | } else { |
| 563 | aed = (struct allocExtDesc *)epos.bh->b_data; |
| 564 | le32_add_cpu(&aed->lengthAllocDescs, adsize); |
| 565 | udf_update_tag(epos.bh->b_data, epos.offset); |
| 566 | mark_buffer_dirty(epos.bh); |
| 567 | } |
| 568 | } |
| 569 | } |
| 570 | |
| 571 | brelse(epos.bh); |
| 572 | brelse(oepos.bh); |
| 573 | |
| 574 | error_return: |
| 575 | mutex_unlock(&sbi->s_alloc_mutex); |
| 576 | return; |
| 577 | } |
| 578 | |
| 579 | static int udf_table_prealloc_blocks(struct super_block *sb, |
| 580 | struct inode *table, uint16_t partition, |
| 581 | uint32_t first_block, uint32_t block_count) |
| 582 | { |
| 583 | struct udf_sb_info *sbi = UDF_SB(sb); |
| 584 | int alloc_count = 0; |
| 585 | uint32_t elen, adsize; |
| 586 | struct kernel_lb_addr eloc; |
| 587 | struct extent_position epos; |
| 588 | int8_t etype = -1; |
| 589 | struct udf_inode_info *iinfo; |
| 590 | |
| 591 | if (first_block >= sbi->s_partmaps[partition].s_partition_len) |
| 592 | return 0; |
| 593 | |
| 594 | iinfo = UDF_I(table); |
| 595 | if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT) |
| 596 | adsize = sizeof(struct short_ad); |
| 597 | else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG) |
| 598 | adsize = sizeof(struct long_ad); |
| 599 | else |
| 600 | return 0; |
| 601 | |
| 602 | mutex_lock(&sbi->s_alloc_mutex); |
| 603 | epos.offset = sizeof(struct unallocSpaceEntry); |
| 604 | epos.block = iinfo->i_location; |
| 605 | epos.bh = NULL; |
| 606 | eloc.logicalBlockNum = 0xFFFFFFFF; |
| 607 | |
| 608 | while (first_block != eloc.logicalBlockNum && |
| 609 | (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) { |
| 610 | udf_debug("eloc=%d, elen=%d, first_block=%d\n", |
| 611 | eloc.logicalBlockNum, elen, first_block); |
| 612 | ; /* empty loop body */ |
| 613 | } |
| 614 | |
| 615 | if (first_block == eloc.logicalBlockNum) { |
| 616 | epos.offset -= adsize; |
| 617 | |
| 618 | alloc_count = (elen >> sb->s_blocksize_bits); |
| 619 | if (alloc_count > block_count) { |
| 620 | alloc_count = block_count; |
| 621 | eloc.logicalBlockNum += alloc_count; |
| 622 | elen -= (alloc_count << sb->s_blocksize_bits); |
| 623 | udf_write_aext(table, &epos, &eloc, |
| 624 | (etype << 30) | elen, 1); |
| 625 | } else |
| 626 | udf_delete_aext(table, epos, eloc, |
| 627 | (etype << 30) | elen); |
| 628 | } else { |
| 629 | alloc_count = 0; |
| 630 | } |
| 631 | |
| 632 | brelse(epos.bh); |
| 633 | |
| 634 | if (alloc_count) |
| 635 | udf_add_free_space(sb, partition, -alloc_count); |
| 636 | mutex_unlock(&sbi->s_alloc_mutex); |
| 637 | return alloc_count; |
| 638 | } |
| 639 | |
| 640 | static int udf_table_new_block(struct super_block *sb, |
| 641 | struct inode *table, uint16_t partition, |
| 642 | uint32_t goal, int *err) |
| 643 | { |
| 644 | struct udf_sb_info *sbi = UDF_SB(sb); |
| 645 | uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF; |
| 646 | uint32_t newblock = 0, adsize; |
| 647 | uint32_t elen, goal_elen = 0; |
| 648 | struct kernel_lb_addr eloc, uninitialized_var(goal_eloc); |
| 649 | struct extent_position epos, goal_epos; |
| 650 | int8_t etype; |
| 651 | struct udf_inode_info *iinfo = UDF_I(table); |
| 652 | |
| 653 | *err = -ENOSPC; |
| 654 | |
| 655 | if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT) |
| 656 | adsize = sizeof(struct short_ad); |
| 657 | else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG) |
| 658 | adsize = sizeof(struct long_ad); |
| 659 | else |
| 660 | return newblock; |
| 661 | |
| 662 | mutex_lock(&sbi->s_alloc_mutex); |
| 663 | if (goal >= sbi->s_partmaps[partition].s_partition_len) |
| 664 | goal = 0; |
| 665 | |
| 666 | /* We search for the closest matching block to goal. If we find |
| 667 | a exact hit, we stop. Otherwise we keep going till we run out |
| 668 | of extents. We store the buffer_head, bloc, and extoffset |
| 669 | of the current closest match and use that when we are done. |
| 670 | */ |
| 671 | epos.offset = sizeof(struct unallocSpaceEntry); |
| 672 | epos.block = iinfo->i_location; |
| 673 | epos.bh = goal_epos.bh = NULL; |
| 674 | |
| 675 | while (spread && |
| 676 | (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) { |
| 677 | if (goal >= eloc.logicalBlockNum) { |
| 678 | if (goal < eloc.logicalBlockNum + |
| 679 | (elen >> sb->s_blocksize_bits)) |
| 680 | nspread = 0; |
| 681 | else |
| 682 | nspread = goal - eloc.logicalBlockNum - |
| 683 | (elen >> sb->s_blocksize_bits); |
| 684 | } else { |
| 685 | nspread = eloc.logicalBlockNum - goal; |
| 686 | } |
| 687 | |
| 688 | if (nspread < spread) { |
| 689 | spread = nspread; |
| 690 | if (goal_epos.bh != epos.bh) { |
| 691 | brelse(goal_epos.bh); |
| 692 | goal_epos.bh = epos.bh; |
| 693 | get_bh(goal_epos.bh); |
| 694 | } |
| 695 | goal_epos.block = epos.block; |
| 696 | goal_epos.offset = epos.offset - adsize; |
| 697 | goal_eloc = eloc; |
| 698 | goal_elen = (etype << 30) | elen; |
| 699 | } |
| 700 | } |
| 701 | |
| 702 | brelse(epos.bh); |
| 703 | |
| 704 | if (spread == 0xFFFFFFFF) { |
| 705 | brelse(goal_epos.bh); |
| 706 | mutex_unlock(&sbi->s_alloc_mutex); |
| 707 | return 0; |
| 708 | } |
| 709 | |
| 710 | /* Only allocate blocks from the beginning of the extent. |
| 711 | That way, we only delete (empty) extents, never have to insert an |
| 712 | extent because of splitting */ |
| 713 | /* This works, but very poorly.... */ |
| 714 | |
| 715 | newblock = goal_eloc.logicalBlockNum; |
| 716 | goal_eloc.logicalBlockNum++; |
| 717 | goal_elen -= sb->s_blocksize; |
| 718 | |
| 719 | if (goal_elen) |
| 720 | udf_write_aext(table, &goal_epos, &goal_eloc, goal_elen, 1); |
| 721 | else |
| 722 | udf_delete_aext(table, goal_epos, goal_eloc, goal_elen); |
| 723 | brelse(goal_epos.bh); |
| 724 | |
| 725 | udf_add_free_space(sb, partition, -1); |
| 726 | |
| 727 | mutex_unlock(&sbi->s_alloc_mutex); |
| 728 | *err = 0; |
| 729 | return newblock; |
| 730 | } |
| 731 | |
| 732 | void udf_free_blocks(struct super_block *sb, struct inode *inode, |
| 733 | struct kernel_lb_addr *bloc, uint32_t offset, |
| 734 | uint32_t count) |
| 735 | { |
| 736 | uint16_t partition = bloc->partitionReferenceNum; |
| 737 | struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition]; |
| 738 | |
| 739 | if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) { |
| 740 | udf_bitmap_free_blocks(sb, map->s_uspace.s_bitmap, |
| 741 | bloc, offset, count); |
| 742 | } else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) { |
| 743 | udf_table_free_blocks(sb, map->s_uspace.s_table, |
| 744 | bloc, offset, count); |
| 745 | } else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) { |
| 746 | udf_bitmap_free_blocks(sb, map->s_fspace.s_bitmap, |
| 747 | bloc, offset, count); |
| 748 | } else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) { |
| 749 | udf_table_free_blocks(sb, map->s_fspace.s_table, |
| 750 | bloc, offset, count); |
| 751 | } |
| 752 | |
| 753 | if (inode) { |
| 754 | inode_sub_bytes(inode, |
| 755 | ((sector_t)count) << sb->s_blocksize_bits); |
| 756 | } |
| 757 | } |
| 758 | |
| 759 | inline int udf_prealloc_blocks(struct super_block *sb, |
| 760 | struct inode *inode, |
| 761 | uint16_t partition, uint32_t first_block, |
| 762 | uint32_t block_count) |
| 763 | { |
| 764 | struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition]; |
| 765 | sector_t allocated; |
| 766 | |
| 767 | if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) |
| 768 | allocated = udf_bitmap_prealloc_blocks(sb, |
| 769 | map->s_uspace.s_bitmap, |
| 770 | partition, first_block, |
| 771 | block_count); |
| 772 | else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) |
| 773 | allocated = udf_table_prealloc_blocks(sb, |
| 774 | map->s_uspace.s_table, |
| 775 | partition, first_block, |
| 776 | block_count); |
| 777 | else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) |
| 778 | allocated = udf_bitmap_prealloc_blocks(sb, |
| 779 | map->s_fspace.s_bitmap, |
| 780 | partition, first_block, |
| 781 | block_count); |
| 782 | else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) |
| 783 | allocated = udf_table_prealloc_blocks(sb, |
| 784 | map->s_fspace.s_table, |
| 785 | partition, first_block, |
| 786 | block_count); |
| 787 | else |
| 788 | return 0; |
| 789 | |
| 790 | if (inode && allocated > 0) |
| 791 | inode_add_bytes(inode, allocated << sb->s_blocksize_bits); |
| 792 | return allocated; |
| 793 | } |
| 794 | |
| 795 | inline int udf_new_block(struct super_block *sb, |
| 796 | struct inode *inode, |
| 797 | uint16_t partition, uint32_t goal, int *err) |
| 798 | { |
| 799 | struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition]; |
| 800 | int block; |
| 801 | |
| 802 | if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) |
| 803 | block = udf_bitmap_new_block(sb, |
| 804 | map->s_uspace.s_bitmap, |
| 805 | partition, goal, err); |
| 806 | else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) |
| 807 | block = udf_table_new_block(sb, |
| 808 | map->s_uspace.s_table, |
| 809 | partition, goal, err); |
| 810 | else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) |
| 811 | block = udf_bitmap_new_block(sb, |
| 812 | map->s_fspace.s_bitmap, |
| 813 | partition, goal, err); |
| 814 | else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) |
| 815 | block = udf_table_new_block(sb, |
| 816 | map->s_fspace.s_table, |
| 817 | partition, goal, err); |
| 818 | else { |
| 819 | *err = -EIO; |
| 820 | return 0; |
| 821 | } |
| 822 | if (inode && block) |
| 823 | inode_add_bytes(inode, sb->s_blocksize); |
| 824 | return block; |
| 825 | } |