1 /* 2 * Copyright (c) 2011-2018 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@dragonflybsd.org> 6 * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org> 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in 16 * the documentation and/or other materials provided with the 17 * distribution. 18 * 3. Neither the name of The DragonFly Project nor the names of its 19 * contributors may be used to endorse or promote products derived 20 * from this software without specific, prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/kernel.h> 38 #include <sys/fcntl.h> 39 #include <sys/buf.h> 40 #include <sys/proc.h> 41 #include <sys/namei.h> 42 #include <sys/mount.h> 43 #include <sys/vnode.h> 44 #include <sys/mountctl.h> 45 46 #include "hammer2.h" 47 48 #define FREEMAP_DEBUG 0 49 50 struct hammer2_fiterate { 51 hammer2_off_t bpref; 52 hammer2_off_t bnext; 53 int loops; 54 int relaxed; 55 }; 56 57 typedef struct hammer2_fiterate hammer2_fiterate_t; 58 59 static int hammer2_freemap_try_alloc(hammer2_chain_t **parentp, 60 hammer2_blockref_t *bref, int radix, 61 hammer2_fiterate_t *iter, hammer2_tid_t mtid); 62 static void hammer2_freemap_init(hammer2_dev_t *hmp, 63 hammer2_key_t key, hammer2_chain_t *chain); 64 static int hammer2_bmap_alloc(hammer2_dev_t *hmp, 65 hammer2_bmap_data_t *bmap, uint16_t class, 66 int n, int sub_key, int radix, hammer2_key_t *basep); 67 static int hammer2_freemap_iterate(hammer2_chain_t **parentp, 68 hammer2_chain_t **chainp, 69 hammer2_fiterate_t *iter); 70 71 /* 72 * Calculate the device offset for the specified FREEMAP_NODE or FREEMAP_LEAF 73 * bref. Return a combined media offset and physical size radix. Freemap 74 * chains use fixed storage offsets in the 4MB reserved area at the 75 * beginning of each 2GB zone 76 * 77 * Rotate between four possibilities. Theoretically this means we have three 78 * good freemaps in case of a crash which we can use as a base for the fixup 79 * scan at mount-time. 80 */ 81 static 82 int 83 hammer2_freemap_reserve(hammer2_chain_t *chain, int radix) 84 { 85 hammer2_blockref_t *bref = &chain->bref; 86 hammer2_off_t off; 87 int index; 88 int index_inc; 89 size_t bytes; 90 91 /* 92 * Physical allocation size. 93 */ 94 bytes = (size_t)1 << radix; 95 96 /* 97 * Calculate block selection index 0..7 of current block. If this 98 * is the first allocation of the block (verses a modification of an 99 * existing block), we use index 0, otherwise we use the next rotating 100 * index. 101 */ 102 if ((bref->data_off & ~HAMMER2_OFF_MASK_RADIX) == 0) { 103 index = 0; 104 } else { 105 off = bref->data_off & ~HAMMER2_OFF_MASK_RADIX & 106 HAMMER2_SEGMASK; 107 off = off / HAMMER2_PBUFSIZE; 108 KKASSERT(off >= HAMMER2_ZONE_FREEMAP_00 && 109 off < HAMMER2_ZONE_FREEMAP_END); 110 index = (int)(off - HAMMER2_ZONE_FREEMAP_00) / 111 HAMMER2_ZONE_FREEMAP_INC; 112 KKASSERT(index >= 0 && index < HAMMER2_NFREEMAPS); 113 if (++index == HAMMER2_NFREEMAPS) 114 index = 0; 115 } 116 117 /* 118 * Calculate the block offset of the reserved block. This will 119 * point into the 4MB reserved area at the base of the appropriate 120 * 2GB zone, once added to the FREEMAP_x selection above. 121 */ 122 index_inc = index * HAMMER2_ZONE_FREEMAP_INC; 123 124 switch(bref->keybits) { 125 /* case HAMMER2_FREEMAP_LEVEL6_RADIX: not applicable */ 126 case HAMMER2_FREEMAP_LEVEL5_RADIX: /* 4EB */ 127 KKASSERT(bref->type == HAMMER2_BREF_TYPE_FREEMAP_NODE); 128 KKASSERT(bytes == HAMMER2_FREEMAP_LEVELN_PSIZE); 129 off = H2FMBASE(bref->key, HAMMER2_FREEMAP_LEVEL5_RADIX) + 130 (index_inc + HAMMER2_ZONE_FREEMAP_00 + 131 HAMMER2_ZONEFM_LEVEL5) * HAMMER2_PBUFSIZE; 132 break; 133 case HAMMER2_FREEMAP_LEVEL4_RADIX: /* 16PB */ 134 KKASSERT(bref->type == HAMMER2_BREF_TYPE_FREEMAP_NODE); 135 KKASSERT(bytes == HAMMER2_FREEMAP_LEVELN_PSIZE); 136 off = H2FMBASE(bref->key, HAMMER2_FREEMAP_LEVEL4_RADIX) + 137 (index_inc + HAMMER2_ZONE_FREEMAP_00 + 138 HAMMER2_ZONEFM_LEVEL4) * HAMMER2_PBUFSIZE; 139 break; 140 case HAMMER2_FREEMAP_LEVEL3_RADIX: /* 64TB */ 141 KKASSERT(bref->type == HAMMER2_BREF_TYPE_FREEMAP_NODE); 142 KKASSERT(bytes == HAMMER2_FREEMAP_LEVELN_PSIZE); 143 off = H2FMBASE(bref->key, HAMMER2_FREEMAP_LEVEL3_RADIX) + 144 (index_inc + HAMMER2_ZONE_FREEMAP_00 + 145 HAMMER2_ZONEFM_LEVEL3) * HAMMER2_PBUFSIZE; 146 break; 147 case HAMMER2_FREEMAP_LEVEL2_RADIX: /* 256GB */ 148 KKASSERT(bref->type == HAMMER2_BREF_TYPE_FREEMAP_NODE); 149 KKASSERT(bytes == HAMMER2_FREEMAP_LEVELN_PSIZE); 150 off = H2FMBASE(bref->key, HAMMER2_FREEMAP_LEVEL2_RADIX) + 151 (index_inc + HAMMER2_ZONE_FREEMAP_00 + 152 HAMMER2_ZONEFM_LEVEL2) * HAMMER2_PBUFSIZE; 153 break; 154 case HAMMER2_FREEMAP_LEVEL1_RADIX: /* 1GB */ 155 KKASSERT(bref->type == HAMMER2_BREF_TYPE_FREEMAP_LEAF); 156 KKASSERT(bytes == HAMMER2_FREEMAP_LEVELN_PSIZE); 157 off = H2FMBASE(bref->key, HAMMER2_FREEMAP_LEVEL1_RADIX) + 158 (index_inc + HAMMER2_ZONE_FREEMAP_00 + 159 HAMMER2_ZONEFM_LEVEL1) * HAMMER2_PBUFSIZE; 160 break; 161 default: 162 panic("freemap: bad radix(2) %p %d\n", bref, bref->keybits); 163 /* NOT REACHED */ 164 off = (hammer2_off_t)-1; 165 break; 166 } 167 bref->data_off = off | radix; 168 #if FREEMAP_DEBUG 169 kprintf("FREEMAP BLOCK TYPE %d %016jx/%d DATA_OFF=%016jx\n", 170 bref->type, bref->key, bref->keybits, bref->data_off); 171 #endif 172 return (0); 173 } 174 175 /* 176 * Normal freemap allocator 177 * 178 * Use available hints to allocate space using the freemap. Create missing 179 * freemap infrastructure on-the-fly as needed (including marking initial 180 * allocations using the iterator as allocated, instantiating new 2GB zones, 181 * and dealing with the end-of-media edge case). 182 * 183 * ip and bpref are only used as a heuristic to determine locality of 184 * reference. bref->key may also be used heuristically. 185 * 186 * This function is a NOP if bytes is 0. 187 */ 188 int 189 hammer2_freemap_alloc(hammer2_chain_t *chain, size_t bytes) 190 { 191 hammer2_dev_t *hmp = chain->hmp; 192 hammer2_blockref_t *bref = &chain->bref; 193 hammer2_chain_t *parent; 194 hammer2_tid_t mtid; 195 int radix; 196 int error; 197 unsigned int hindex; 198 hammer2_fiterate_t iter; 199 200 /* 201 * If allocating or downsizing to zero we just get rid of whatever 202 * data_off we had. 203 */ 204 if (bytes == 0) { 205 chain->bref.data_off = 0; 206 return 0; 207 } 208 209 KKASSERT(hmp->spmp); 210 mtid = hammer2_trans_sub(hmp->spmp); 211 212 /* 213 * Validate the allocation size. It must be a power of 2. 214 * 215 * For now require that the caller be aware of the minimum 216 * allocation (1K). 217 */ 218 radix = hammer2_getradix(bytes); 219 KKASSERT((size_t)1 << radix == bytes); 220 221 if (bref->type == HAMMER2_BREF_TYPE_FREEMAP_NODE || 222 bref->type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) { 223 /* 224 * Freemap blocks themselves are assigned from the reserve 225 * area, not allocated from the freemap. 226 */ 227 error = hammer2_freemap_reserve(chain, radix); 228 229 return error; 230 } 231 232 KKASSERT(bytes >= HAMMER2_ALLOC_MIN && bytes <= HAMMER2_ALLOC_MAX); 233 234 /* 235 * Calculate the starting point for our allocation search. 236 * 237 * Each freemap leaf is dedicated to a specific freemap_radix. 238 * The freemap_radix can be more fine-grained than the device buffer 239 * radix which results in inodes being grouped together in their 240 * own segment, terminal-data (16K or less) and initial indirect 241 * block being grouped together, and then full-indirect and full-data 242 * blocks (64K) being grouped together. 243 * 244 * The single most important aspect of this is the inode grouping 245 * because that is what allows 'find' and 'ls' and other filesystem 246 * topology operations to run fast. 247 */ 248 #if 0 249 if (bref->data_off & ~HAMMER2_OFF_MASK_RADIX) 250 bpref = bref->data_off & ~HAMMER2_OFF_MASK_RADIX; 251 else if (trans->tmp_bpref) 252 bpref = trans->tmp_bpref; 253 else if (trans->tmp_ip) 254 bpref = trans->tmp_ip->chain->bref.data_off; 255 else 256 #endif 257 /* 258 * Heuristic tracking index. We would like one for each distinct 259 * bref type if possible. heur_freemap[] has room for two classes 260 * for each type. At a minimum we have to break-up our heuristic 261 * by device block sizes. 262 */ 263 hindex = hammer2_devblkradix(radix) - HAMMER2_MINIORADIX; 264 KKASSERT(hindex < HAMMER2_FREEMAP_HEUR_NRADIX); 265 hindex += bref->type * HAMMER2_FREEMAP_HEUR_NRADIX; 266 hindex &= HAMMER2_FREEMAP_HEUR_TYPES * HAMMER2_FREEMAP_HEUR_NRADIX - 1; 267 KKASSERT(hindex < HAMMER2_FREEMAP_HEUR_SIZE); 268 269 iter.bpref = hmp->heur_freemap[hindex]; 270 iter.relaxed = hmp->freemap_relaxed; 271 272 /* 273 * Make sure bpref is in-bounds. It's ok if bpref covers a zone's 274 * reserved area, the try code will iterate past it. 275 */ 276 if (iter.bpref > hmp->voldata.volu_size) 277 iter.bpref = hmp->voldata.volu_size - 1; 278 279 /* 280 * Iterate the freemap looking for free space before and after. 281 */ 282 parent = &hmp->fchain; 283 hammer2_chain_ref(parent); 284 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS); 285 error = HAMMER2_ERROR_EAGAIN; 286 iter.bnext = iter.bpref; 287 iter.loops = 0; 288 289 while (error == HAMMER2_ERROR_EAGAIN) { 290 error = hammer2_freemap_try_alloc(&parent, bref, radix, 291 &iter, mtid); 292 } 293 hmp->freemap_relaxed |= iter.relaxed; /* heuristical, SMP race ok */ 294 hmp->heur_freemap[hindex] = iter.bnext; 295 hammer2_chain_unlock(parent); 296 hammer2_chain_drop(parent); 297 298 return (error); 299 } 300 301 static int 302 hammer2_freemap_try_alloc(hammer2_chain_t **parentp, 303 hammer2_blockref_t *bref, int radix, 304 hammer2_fiterate_t *iter, hammer2_tid_t mtid) 305 { 306 hammer2_dev_t *hmp = (*parentp)->hmp; 307 hammer2_off_t l0size; 308 hammer2_off_t l1size; 309 hammer2_off_t l1mask; 310 hammer2_key_t key_dummy; 311 hammer2_chain_t *chain; 312 hammer2_off_t key; 313 size_t bytes; 314 uint16_t class; 315 int error; 316 317 /* 318 * Calculate the number of bytes being allocated, the number 319 * of contiguous bits of bitmap being allocated, and the bitmap 320 * mask. 321 * 322 * WARNING! cpu hardware may mask bits == 64 -> 0 and blow up the 323 * mask calculation. 324 */ 325 bytes = (size_t)1 << radix; 326 class = (bref->type << 8) | hammer2_devblkradix(radix); 327 328 /* 329 * Lookup the level1 freemap chain, creating and initializing one 330 * if necessary. Intermediate levels will be created automatically 331 * when necessary by hammer2_chain_create(). 332 */ 333 key = H2FMBASE(iter->bnext, HAMMER2_FREEMAP_LEVEL1_RADIX); 334 l0size = HAMMER2_FREEMAP_LEVEL0_SIZE; 335 l1size = HAMMER2_FREEMAP_LEVEL1_SIZE; 336 l1mask = l1size - 1; 337 338 chain = hammer2_chain_lookup(parentp, &key_dummy, key, key + l1mask, 339 &error, 340 HAMMER2_LOOKUP_ALWAYS | 341 HAMMER2_LOOKUP_MATCHIND); 342 343 if (chain == NULL) { 344 /* 345 * Create the missing leaf, be sure to initialize 346 * the auxillary freemap tracking information in 347 * the bref.check.freemap structure. 348 */ 349 #if 0 350 kprintf("freemap create L1 @ %016jx bpref %016jx\n", 351 key, iter->bpref); 352 #endif 353 error = hammer2_chain_create(parentp, &chain, NULL, hmp->spmp, 354 HAMMER2_METH_DEFAULT, 355 key, HAMMER2_FREEMAP_LEVEL1_RADIX, 356 HAMMER2_BREF_TYPE_FREEMAP_LEAF, 357 HAMMER2_FREEMAP_LEVELN_PSIZE, 358 mtid, 0, 0); 359 KKASSERT(error == 0); 360 if (error == 0) { 361 hammer2_chain_modify(chain, mtid, 0, 0); 362 bzero(&chain->data->bmdata[0], 363 HAMMER2_FREEMAP_LEVELN_PSIZE); 364 chain->bref.check.freemap.bigmask = (uint32_t)-1; 365 chain->bref.check.freemap.avail = l1size; 366 /* bref.methods should already be inherited */ 367 368 hammer2_freemap_init(hmp, key, chain); 369 } 370 } else if (chain->error) { 371 /* 372 * Error during lookup. 373 */ 374 kprintf("hammer2_freemap_try_alloc: %016jx: error %s\n", 375 (intmax_t)bref->data_off, 376 hammer2_error_str(chain->error)); 377 error = HAMMER2_ERROR_EIO; 378 } else if ((chain->bref.check.freemap.bigmask & 379 ((size_t)1 << radix)) == 0) { 380 /* 381 * Already flagged as not having enough space 382 */ 383 error = HAMMER2_ERROR_ENOSPC; 384 } else { 385 /* 386 * Modify existing chain to setup for adjustment. 387 */ 388 hammer2_chain_modify(chain, mtid, 0, 0); 389 } 390 391 /* 392 * Scan 4MB entries. 393 */ 394 if (error == 0) { 395 hammer2_bmap_data_t *bmap; 396 hammer2_key_t base_key; 397 int count; 398 int start; 399 int n; 400 401 KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF); 402 start = (int)((iter->bnext - key) >> 403 HAMMER2_FREEMAP_LEVEL0_RADIX); 404 KKASSERT(start >= 0 && start < HAMMER2_FREEMAP_COUNT); 405 hammer2_chain_modify(chain, mtid, 0, 0); 406 407 error = HAMMER2_ERROR_ENOSPC; 408 for (count = 0; count < HAMMER2_FREEMAP_COUNT; ++count) { 409 int availchk; 410 411 if (start + count >= HAMMER2_FREEMAP_COUNT && 412 start - count < 0) { 413 break; 414 } 415 416 /* 417 * Calculate bmap pointer from thart starting index 418 * forwards. 419 * 420 * NOTE: bmap pointer is invalid if n >= FREEMAP_COUNT. 421 */ 422 n = start + count; 423 bmap = &chain->data->bmdata[n]; 424 425 if (n >= HAMMER2_FREEMAP_COUNT) { 426 availchk = 0; 427 } else if (bmap->avail) { 428 availchk = 1; 429 } else if (radix < HAMMER2_FREEMAP_BLOCK_RADIX && 430 (bmap->linear & HAMMER2_FREEMAP_BLOCK_MASK)) { 431 availchk = 1; 432 } else { 433 availchk = 0; 434 } 435 436 /* 437 * Try to allocate from a matching freemap class 438 * superblock. If we are in relaxed mode we allocate 439 * from any freemap class superblock. 440 */ 441 if (availchk && 442 (bmap->class == 0 || bmap->class == class || 443 iter->relaxed)) { 444 base_key = key + n * l0size; 445 error = hammer2_bmap_alloc(hmp, bmap, 446 class, n, 447 (int)bref->key, 448 radix, 449 &base_key); 450 if (error != HAMMER2_ERROR_ENOSPC) { 451 key = base_key; 452 break; 453 } 454 } 455 456 /* 457 * Calculate bmap pointer from thart starting index 458 * backwards (locality). 459 * 460 * Must recalculate after potentially having called 461 * hammer2_bmap_alloc() above in case chain was 462 * reallocated. 463 * 464 * NOTE: bmap pointer is invalid if n < 0. 465 */ 466 n = start - count; 467 bmap = &chain->data->bmdata[n]; 468 if (n < 0) { 469 availchk = 0; 470 } else if (bmap->avail) { 471 availchk = 1; 472 } else if (radix < HAMMER2_FREEMAP_BLOCK_RADIX && 473 (bmap->linear & HAMMER2_FREEMAP_BLOCK_MASK)) { 474 availchk = 1; 475 } else { 476 availchk = 0; 477 } 478 479 /* 480 * Try to allocate from a matching freemap class 481 * superblock. If we are in relaxed mode we allocate 482 * from any freemap class superblock. 483 */ 484 if (availchk && 485 (bmap->class == 0 || bmap->class == class || 486 iter->relaxed)) { 487 base_key = key + n * l0size; 488 error = hammer2_bmap_alloc(hmp, bmap, 489 class, n, 490 (int)bref->key, 491 radix, 492 &base_key); 493 if (error != HAMMER2_ERROR_ENOSPC) { 494 key = base_key; 495 break; 496 } 497 } 498 } 499 500 /* 501 * We only know for sure that we can clear the bitmap bit 502 * if we scanned the entire array (start == 0). 503 */ 504 if (error == HAMMER2_ERROR_ENOSPC && start == 0) { 505 chain->bref.check.freemap.bigmask &= 506 (uint32_t)~((size_t)1 << radix); 507 } 508 /* XXX also scan down from original count */ 509 } 510 511 if (error == 0) { 512 /* 513 * Assert validity. Must be beyond the static allocator used 514 * by newfs_hammer2 (and thus also beyond the aux area), 515 * not go past the volume size, and must not be in the 516 * reserved segment area for a zone. 517 */ 518 KKASSERT(key >= hmp->voldata.allocator_beg && 519 key + bytes <= hmp->voldata.volu_size); 520 KKASSERT((key & HAMMER2_ZONE_MASK64) >= HAMMER2_ZONE_SEG); 521 bref->data_off = key | radix; 522 523 /* 524 * Record dedupability. The dedup bits are cleared 525 * when bulkfree transitions the freemap from 11->10, 526 * and asserted to be clear on the 10->00 transition. 527 * 528 * We must record the bitmask with the chain locked 529 * at the time we set the allocation bits to avoid 530 * racing a bulkfree. 531 */ 532 if (bref->type == HAMMER2_BREF_TYPE_DATA) 533 hammer2_io_dedup_set(hmp, bref); 534 #if 0 535 kprintf("alloc cp=%p %016jx %016jx using %016jx\n", 536 chain, 537 bref->key, bref->data_off, chain->bref.data_off); 538 #endif 539 } else if (error == HAMMER2_ERROR_ENOSPC) { 540 /* 541 * Return EAGAIN with next iteration in iter->bnext, or 542 * return ENOSPC if the allocation map has been exhausted. 543 */ 544 error = hammer2_freemap_iterate(parentp, &chain, iter); 545 } 546 547 /* 548 * Cleanup 549 */ 550 if (chain) { 551 hammer2_chain_unlock(chain); 552 hammer2_chain_drop(chain); 553 } 554 return (error); 555 } 556 557 /* 558 * Allocate (1<<radix) bytes from the bmap whos base data offset is (*basep). 559 * 560 * If the linear iterator is mid-block we use it directly (the bitmap should 561 * already be marked allocated), otherwise we search for a block in the 562 * bitmap that fits the allocation request. 563 * 564 * A partial bitmap allocation sets the minimum bitmap granularity (16KB) 565 * to fully allocated and adjusts the linear allocator to allow the 566 * remaining space to be allocated. 567 * 568 * sub_key is the lower 32 bits of the chain->bref.key for the chain whos 569 * bref is being allocated. If the radix represents an allocation >= 16KB 570 * (aka HAMMER2_FREEMAP_BLOCK_RADIX) we try to use this key to select the 571 * blocks directly out of the bmap. 572 */ 573 static 574 int 575 hammer2_bmap_alloc(hammer2_dev_t *hmp, hammer2_bmap_data_t *bmap, 576 uint16_t class, int n, int sub_key, 577 int radix, hammer2_key_t *basep) 578 { 579 size_t size; 580 size_t bgsize; 581 int bmradix; 582 hammer2_bitmap_t bmmask; 583 int offset; 584 int i; 585 int j; 586 587 /* 588 * Take into account 2-bits per block when calculating bmradix. 589 */ 590 size = (size_t)1 << radix; 591 592 if (radix <= HAMMER2_FREEMAP_BLOCK_RADIX) { 593 bmradix = 2; 594 /* (16K) 2 bits per allocation block */ 595 } else { 596 bmradix = (hammer2_bitmap_t)2 << 597 (radix - HAMMER2_FREEMAP_BLOCK_RADIX); 598 /* (32K-256K) 4, 8, 16, 32 bits per allocation block */ 599 } 600 601 /* 602 * Use the linear iterator to pack small allocations, otherwise 603 * fall-back to finding a free 16KB chunk. The linear iterator 604 * is only valid when *NOT* on a freemap chunking boundary (16KB). 605 * If it is the bitmap must be scanned. It can become invalid 606 * once we pack to the boundary. We adjust it after a bitmap 607 * allocation only for sub-16KB allocations (so the perfectly good 608 * previous value can still be used for fragments when 16KB+ 609 * allocations are made inbetween fragmentary allocations). 610 * 611 * Beware of hardware artifacts when bmradix == 64 (intermediate 612 * result can wind up being '1' instead of '0' if hardware masks 613 * bit-count & 63). 614 * 615 * NOTE: j needs to be even in the j= calculation. As an artifact 616 * of the /2 division, our bitmask has to clear bit 0. 617 * 618 * NOTE: TODO this can leave little unallocatable fragments lying 619 * around. 620 */ 621 if (((uint32_t)bmap->linear & HAMMER2_FREEMAP_BLOCK_MASK) + size <= 622 HAMMER2_FREEMAP_BLOCK_SIZE && 623 (bmap->linear & HAMMER2_FREEMAP_BLOCK_MASK) && 624 bmap->linear < HAMMER2_SEGSIZE) { 625 /* 626 * Use linear iterator if it is not block-aligned to avoid 627 * wasting space. 628 * 629 * Calculate the bitmapq[] index (i) and calculate the 630 * shift count within the 64-bit bitmapq[] entry. 631 * 632 * The freemap block size is 16KB, but each bitmap 633 * entry is two bits so use a little trick to get 634 * a (j) shift of 0, 2, 4, ... 62 in 16KB chunks. 635 */ 636 KKASSERT(bmap->linear >= 0 && 637 bmap->linear + size <= HAMMER2_SEGSIZE && 638 (bmap->linear & (HAMMER2_ALLOC_MIN - 1)) == 0); 639 offset = bmap->linear; 640 i = offset / (HAMMER2_SEGSIZE / HAMMER2_BMAP_ELEMENTS); 641 j = (offset / (HAMMER2_FREEMAP_BLOCK_SIZE / 2)) & 62; 642 bmmask = (bmradix == HAMMER2_BMAP_BITS_PER_ELEMENT) ? 643 HAMMER2_BMAP_ALLONES : 644 ((hammer2_bitmap_t)1 << bmradix) - 1; 645 bmmask <<= j; 646 bmap->linear = offset + size; 647 } else { 648 /* 649 * Try to index a starting point based on sub_key. This 650 * attempts to restore sequential block ordering on-disk 651 * whenever possible, even if data is committed out of 652 * order. 653 * 654 * i - Index bitmapq[], full data range represented is 655 * HAMMER2_BMAP_SIZE. 656 * 657 * j - Index within bitmapq[i], full data range represented is 658 * HAMMER2_BMAP_INDEX_SIZE. 659 * 660 * WARNING! 661 */ 662 i = -1; 663 j = -1; 664 665 switch(class >> 8) { 666 case HAMMER2_BREF_TYPE_DATA: 667 if (radix >= HAMMER2_FREEMAP_BLOCK_RADIX) { 668 i = (sub_key & HAMMER2_BMAP_MASK) / 669 (HAMMER2_BMAP_SIZE / HAMMER2_BMAP_ELEMENTS); 670 j = (sub_key & HAMMER2_BMAP_INDEX_MASK) / 671 (HAMMER2_BMAP_INDEX_SIZE / 672 HAMMER2_BMAP_BLOCKS_PER_ELEMENT); 673 j = j * 2; 674 } 675 break; 676 case HAMMER2_BREF_TYPE_INODE: 677 break; 678 default: 679 break; 680 } 681 if (i >= 0) { 682 KKASSERT(i < HAMMER2_BMAP_ELEMENTS && 683 j < 2 * HAMMER2_BMAP_BLOCKS_PER_ELEMENT); 684 KKASSERT(j + bmradix <= HAMMER2_BMAP_BITS_PER_ELEMENT); 685 bmmask = (bmradix == HAMMER2_BMAP_BITS_PER_ELEMENT) ? 686 HAMMER2_BMAP_ALLONES : 687 ((hammer2_bitmap_t)1 << bmradix) - 1; 688 bmmask <<= j; 689 690 if ((bmap->bitmapq[i] & bmmask) == 0) 691 goto success; 692 } 693 694 /* 695 * General element scan. 696 * 697 * WARNING: (j) is iterating a bit index (by 2's) 698 */ 699 for (i = 0; i < HAMMER2_BMAP_ELEMENTS; ++i) { 700 bmmask = (bmradix == HAMMER2_BMAP_BITS_PER_ELEMENT) ? 701 HAMMER2_BMAP_ALLONES : 702 ((hammer2_bitmap_t)1 << bmradix) - 1; 703 for (j = 0; 704 j < HAMMER2_BMAP_BITS_PER_ELEMENT; 705 j += bmradix) { 706 if ((bmap->bitmapq[i] & bmmask) == 0) 707 goto success; 708 bmmask <<= bmradix; 709 } 710 } 711 /*fragments might remain*/ 712 /*KKASSERT(bmap->avail == 0);*/ 713 return (HAMMER2_ERROR_ENOSPC); 714 success: 715 offset = i * (HAMMER2_SEGSIZE / HAMMER2_BMAP_ELEMENTS) + 716 (j * (HAMMER2_FREEMAP_BLOCK_SIZE / 2)); 717 if (size & HAMMER2_FREEMAP_BLOCK_MASK) 718 bmap->linear = offset + size; 719 } 720 721 /* 8 x (64/2) -> 256 x 16K -> 4MB */ 722 KKASSERT(i >= 0 && i < HAMMER2_BMAP_ELEMENTS); 723 724 /* 725 * Optimize the buffer cache to avoid unnecessary read-before-write 726 * operations. 727 * 728 * The device block size could be larger than the allocation size 729 * so the actual bitmap test is somewhat more involved. We have 730 * to use a compatible buffer size for this operation. 731 */ 732 if ((bmap->bitmapq[i] & bmmask) == 0 && 733 hammer2_devblksize(size) != size) { 734 size_t psize = hammer2_devblksize(size); 735 hammer2_off_t pmask = (hammer2_off_t)psize - 1; 736 int pbmradix = (hammer2_bitmap_t)2 << 737 (hammer2_devblkradix(radix) - 738 HAMMER2_FREEMAP_BLOCK_RADIX); 739 hammer2_bitmap_t pbmmask; 740 int pradix = hammer2_getradix(psize); 741 742 pbmmask = (pbmradix == HAMMER2_BMAP_BITS_PER_ELEMENT) ? 743 HAMMER2_BMAP_ALLONES : 744 ((hammer2_bitmap_t)1 << pbmradix) - 1; 745 while ((pbmmask & bmmask) == 0) 746 pbmmask <<= pbmradix; 747 748 #if 0 749 kprintf("%016jx mask %016jx %016jx %016jx (%zd/%zd)\n", 750 *basep + offset, bmap->bitmapq[i], 751 pbmmask, bmmask, size, psize); 752 #endif 753 754 if ((bmap->bitmapq[i] & pbmmask) == 0) { 755 hammer2_io_t *dio; 756 757 hammer2_io_newnz(hmp, class >> 8, 758 (*basep + (offset & ~pmask)) | 759 pradix, psize, &dio); 760 hammer2_io_putblk(&dio); 761 } 762 } 763 764 #if 0 765 /* 766 * When initializing a new inode segment also attempt to initialize 767 * an adjacent segment. Be careful not to index beyond the array 768 * bounds. 769 * 770 * We do this to try to localize inode accesses to improve 771 * directory scan rates. XXX doesn't improve scan rates. 772 */ 773 if (size == HAMMER2_INODE_BYTES) { 774 if (n & 1) { 775 if (bmap[-1].radix == 0 && bmap[-1].avail) 776 bmap[-1].radix = radix; 777 } else { 778 if (bmap[1].radix == 0 && bmap[1].avail) 779 bmap[1].radix = radix; 780 } 781 } 782 #endif 783 /* 784 * Calculate the bitmap-granular change in bgsize for the volume 785 * header. We cannot use the fine-grained change here because 786 * the bulkfree code can't undo it. If the bitmap element is already 787 * marked allocated it has already been accounted for. 788 */ 789 if (radix < HAMMER2_FREEMAP_BLOCK_RADIX) { 790 if (bmap->bitmapq[i] & bmmask) 791 bgsize = 0; 792 else 793 bgsize = HAMMER2_FREEMAP_BLOCK_SIZE; 794 } else { 795 bgsize = size; 796 } 797 798 /* 799 * Adjust the bitmap, set the class (it might have been 0), 800 * and available bytes, update the allocation offset (*basep) 801 * from the L0 base to the actual offset. 802 * 803 * Do not override the class if doing a relaxed class allocation. 804 * 805 * avail must reflect the bitmap-granular availability. The allocator 806 * tests will also check the linear iterator. 807 */ 808 bmap->bitmapq[i] |= bmmask; 809 if (bmap->class == 0) 810 bmap->class = class; 811 bmap->avail -= bgsize; 812 *basep += offset; 813 814 /* 815 * Adjust the volume header's allocator_free parameter. This 816 * parameter has to be fixed up by bulkfree which has no way to 817 * figure out sub-16K chunking, so it must be adjusted by the 818 * bitmap-granular size. 819 */ 820 if (bgsize) { 821 hammer2_voldata_lock(hmp); 822 hammer2_voldata_modify(hmp); 823 hmp->voldata.allocator_free -= bgsize; 824 hammer2_voldata_unlock(hmp); 825 } 826 827 return(0); 828 } 829 830 /* 831 * Initialize a freemap for the storage area (in bytes) that begins at (key). 832 */ 833 static 834 void 835 hammer2_freemap_init(hammer2_dev_t *hmp, hammer2_key_t key, 836 hammer2_chain_t *chain) 837 { 838 hammer2_off_t l1size; 839 hammer2_off_t lokey; 840 hammer2_off_t hikey; 841 hammer2_bmap_data_t *bmap; 842 int count; 843 844 /* 845 * LEVEL1 is 1GB, there are two level1 1GB freemaps per 2GB zone. 846 */ 847 l1size = HAMMER2_FREEMAP_LEVEL1_SIZE; 848 849 /* 850 * Calculate the portion of the 1GB map that should be initialized 851 * as free. Portions below or after will be initialized as allocated. 852 * SEGMASK-align the areas so we don't have to worry about sub-scans 853 * or endianess when using memset. 854 * 855 * WARNING! It is possible for lokey to be larger than hikey if the 856 * entire 2GB segment is within the static allocation. 857 */ 858 /* 859 * (1) Ensure that all statically allocated space from newfs_hammer2 860 * is marked allocated, and take it up to the level1 base for 861 * this key. 862 */ 863 lokey = (hmp->voldata.allocator_beg + HAMMER2_SEGMASK64) & 864 ~HAMMER2_SEGMASK64; 865 if (lokey < H2FMBASE(key, HAMMER2_FREEMAP_LEVEL1_RADIX)) 866 lokey = H2FMBASE(key, HAMMER2_FREEMAP_LEVEL1_RADIX); 867 868 /* 869 * (2) Ensure that the reserved area is marked allocated (typically 870 * the first 4MB of each 2GB area being represented). Since 871 * each LEAF represents 1GB of storage and the zone is 2GB, we 872 * have to adjust lowkey upward every other LEAF sequentially. 873 */ 874 if (lokey < H2FMZONEBASE(key) + HAMMER2_ZONE_SEG64) 875 lokey = H2FMZONEBASE(key) + HAMMER2_ZONE_SEG64; 876 877 /* 878 * (3) Ensure that any trailing space at the end-of-volume is marked 879 * allocated. 880 */ 881 hikey = key + HAMMER2_FREEMAP_LEVEL1_SIZE; 882 if (hikey > hmp->voldata.volu_size) { 883 hikey = hmp->voldata.volu_size & ~HAMMER2_SEGMASK64; 884 } 885 886 /* 887 * Heuristic highest possible value 888 */ 889 chain->bref.check.freemap.avail = HAMMER2_FREEMAP_LEVEL1_SIZE; 890 bmap = &chain->data->bmdata[0]; 891 892 /* 893 * Initialize bitmap (bzero'd by caller) 894 */ 895 for (count = 0; count < HAMMER2_FREEMAP_COUNT; ++count) { 896 if (key < lokey || key >= hikey) { 897 memset(bmap->bitmapq, -1, 898 sizeof(bmap->bitmapq)); 899 bmap->avail = 0; 900 bmap->linear = HAMMER2_SEGSIZE; 901 chain->bref.check.freemap.avail -= 902 HAMMER2_FREEMAP_LEVEL0_SIZE; 903 } else { 904 bmap->avail = HAMMER2_FREEMAP_LEVEL0_SIZE; 905 } 906 key += HAMMER2_FREEMAP_LEVEL0_SIZE; 907 ++bmap; 908 } 909 } 910 911 /* 912 * The current Level 1 freemap has been exhausted, iterate to the next 913 * one, return ENOSPC if no freemaps remain. 914 * 915 * At least two loops are required. If we are not in relaxed mode and 916 * we run out of storage we enter relaxed mode and do a third loop. 917 * The relaxed mode is recorded back in the hmp so once we enter the mode 918 * we remain relaxed until stuff begins to get freed and only do 2 loops. 919 * 920 * XXX this should rotate back to the beginning to handle freed-up space 921 * XXX or use intermediate entries to locate free space. TODO 922 */ 923 static int 924 hammer2_freemap_iterate(hammer2_chain_t **parentp, hammer2_chain_t **chainp, 925 hammer2_fiterate_t *iter) 926 { 927 hammer2_dev_t *hmp = (*parentp)->hmp; 928 929 iter->bnext &= ~HAMMER2_FREEMAP_LEVEL1_MASK; 930 iter->bnext += HAMMER2_FREEMAP_LEVEL1_SIZE; 931 if (iter->bnext >= hmp->voldata.volu_size) { 932 iter->bnext = 0; 933 if (++iter->loops >= 2) { 934 if (iter->relaxed == 0) 935 iter->relaxed = 1; 936 else 937 return (HAMMER2_ERROR_ENOSPC); 938 } 939 } 940 return(HAMMER2_ERROR_EAGAIN); 941 } 942 943 /* 944 * Adjust the bit-pattern for data in the freemap bitmap according to 945 * (how). This code is called from on-mount recovery to fixup (mark 946 * as allocated) blocks whos freemap upates might not have been committed 947 * in the last crash and is used by the bulk freemap scan to stage frees. 948 * 949 * WARNING! Cannot be called with a empty-data bref (radix == 0). 950 * 951 * XXX currently disabled when how == 0 (the normal real-time case). At 952 * the moment we depend on the bulk freescan to actually free blocks. It 953 * will still call this routine with a non-zero how to stage possible frees 954 * and to do the actual free. 955 */ 956 void 957 hammer2_freemap_adjust(hammer2_dev_t *hmp, hammer2_blockref_t *bref, 958 int how) 959 { 960 hammer2_off_t data_off = bref->data_off; 961 hammer2_chain_t *chain; 962 hammer2_chain_t *parent; 963 hammer2_bmap_data_t *bmap; 964 hammer2_key_t key; 965 hammer2_key_t key_dummy; 966 hammer2_off_t l0size; 967 hammer2_off_t l1size; 968 hammer2_off_t l1mask; 969 hammer2_tid_t mtid; 970 hammer2_bitmap_t *bitmap; 971 const hammer2_bitmap_t bmmask00 = 0; 972 hammer2_bitmap_t bmmask01; 973 hammer2_bitmap_t bmmask10; 974 hammer2_bitmap_t bmmask11; 975 size_t bytes; 976 uint16_t class; 977 int radix; 978 int start; 979 int count; 980 int modified = 0; 981 int error; 982 size_t bgsize = 0; 983 984 KKASSERT(how == HAMMER2_FREEMAP_DORECOVER); 985 986 KKASSERT(hmp->spmp); 987 mtid = hammer2_trans_sub(hmp->spmp); 988 989 radix = (int)data_off & HAMMER2_OFF_MASK_RADIX; 990 KKASSERT(radix != 0); 991 data_off &= ~HAMMER2_OFF_MASK_RADIX; 992 KKASSERT(radix <= HAMMER2_RADIX_MAX); 993 994 if (radix) 995 bytes = (size_t)1 << radix; 996 else 997 bytes = 0; 998 class = (bref->type << 8) | hammer2_devblkradix(radix); 999 1000 /* 1001 * We can't adjust the freemap for data allocations made by 1002 * newfs_hammer2. 1003 */ 1004 if (data_off < hmp->voldata.allocator_beg) 1005 return; 1006 1007 KKASSERT((data_off & HAMMER2_ZONE_MASK64) >= HAMMER2_ZONE_SEG); 1008 1009 /* 1010 * Lookup the level1 freemap chain. The chain must exist. 1011 */ 1012 key = H2FMBASE(data_off, HAMMER2_FREEMAP_LEVEL1_RADIX); 1013 l0size = HAMMER2_FREEMAP_LEVEL0_SIZE; 1014 l1size = HAMMER2_FREEMAP_LEVEL1_SIZE; 1015 l1mask = l1size - 1; 1016 1017 parent = &hmp->fchain; 1018 hammer2_chain_ref(parent); 1019 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS); 1020 1021 chain = hammer2_chain_lookup(&parent, &key_dummy, key, key + l1mask, 1022 &error, 1023 HAMMER2_LOOKUP_ALWAYS | 1024 HAMMER2_LOOKUP_MATCHIND); 1025 1026 /* 1027 * Stop early if we are trying to free something but no leaf exists. 1028 */ 1029 if (chain == NULL && how != HAMMER2_FREEMAP_DORECOVER) { 1030 kprintf("hammer2_freemap_adjust: %016jx: no chain\n", 1031 (intmax_t)bref->data_off); 1032 goto done; 1033 } 1034 if (chain->error) { 1035 kprintf("hammer2_freemap_adjust: %016jx: error %s\n", 1036 (intmax_t)bref->data_off, 1037 hammer2_error_str(chain->error)); 1038 hammer2_chain_unlock(chain); 1039 hammer2_chain_drop(chain); 1040 chain = NULL; 1041 goto done; 1042 } 1043 1044 /* 1045 * Create any missing leaf(s) if we are doing a recovery (marking 1046 * the block(s) as being allocated instead of being freed). Be sure 1047 * to initialize the auxillary freemap tracking info in the 1048 * bref.check.freemap structure. 1049 */ 1050 if (chain == NULL && how == HAMMER2_FREEMAP_DORECOVER) { 1051 error = hammer2_chain_create(&parent, &chain, NULL, hmp->spmp, 1052 HAMMER2_METH_DEFAULT, 1053 key, HAMMER2_FREEMAP_LEVEL1_RADIX, 1054 HAMMER2_BREF_TYPE_FREEMAP_LEAF, 1055 HAMMER2_FREEMAP_LEVELN_PSIZE, 1056 mtid, 0, 0); 1057 1058 if (hammer2_debug & 0x0040) { 1059 kprintf("fixup create chain %p %016jx:%d\n", 1060 chain, chain->bref.key, chain->bref.keybits); 1061 } 1062 1063 if (error == 0) { 1064 error = hammer2_chain_modify(chain, mtid, 0, 0); 1065 KKASSERT(error == 0); 1066 bzero(&chain->data->bmdata[0], 1067 HAMMER2_FREEMAP_LEVELN_PSIZE); 1068 chain->bref.check.freemap.bigmask = (uint32_t)-1; 1069 chain->bref.check.freemap.avail = l1size; 1070 /* bref.methods should already be inherited */ 1071 1072 hammer2_freemap_init(hmp, key, chain); 1073 } 1074 /* XXX handle error */ 1075 } 1076 1077 #if FREEMAP_DEBUG 1078 kprintf("FREEMAP ADJUST TYPE %d %016jx/%d DATA_OFF=%016jx\n", 1079 chain->bref.type, chain->bref.key, 1080 chain->bref.keybits, chain->bref.data_off); 1081 #endif 1082 1083 /* 1084 * Calculate the bitmask (runs in 2-bit pairs). 1085 */ 1086 start = ((int)(data_off >> HAMMER2_FREEMAP_BLOCK_RADIX) & 15) * 2; 1087 bmmask01 = (hammer2_bitmap_t)1 << start; 1088 bmmask10 = (hammer2_bitmap_t)2 << start; 1089 bmmask11 = (hammer2_bitmap_t)3 << start; 1090 1091 /* 1092 * Fixup the bitmap. Partial blocks cannot be fully freed unless 1093 * a bulk scan is able to roll them up. 1094 */ 1095 if (radix < HAMMER2_FREEMAP_BLOCK_RADIX) { 1096 count = 1; 1097 if (how == HAMMER2_FREEMAP_DOREALFREE) 1098 how = HAMMER2_FREEMAP_DOMAYFREE; 1099 } else { 1100 count = 1 << (radix - HAMMER2_FREEMAP_BLOCK_RADIX); 1101 } 1102 1103 /* 1104 * [re]load the bmap and bitmap pointers. Each bmap entry covers 1105 * a 4MB swath. The bmap itself (LEVEL1) covers 2GB. 1106 * 1107 * Be sure to reset the linear iterator to ensure that the adjustment 1108 * is not ignored. 1109 */ 1110 again: 1111 bmap = &chain->data->bmdata[(int)(data_off >> HAMMER2_SEGRADIX) & 1112 (HAMMER2_FREEMAP_COUNT - 1)]; 1113 bitmap = &bmap->bitmapq[(int)(data_off >> (HAMMER2_SEGRADIX - 3)) & 7]; 1114 1115 if (modified) 1116 bmap->linear = 0; 1117 1118 while (count) { 1119 KKASSERT(bmmask11); 1120 if (how == HAMMER2_FREEMAP_DORECOVER) { 1121 /* 1122 * Recovery request, mark as allocated. 1123 */ 1124 if ((*bitmap & bmmask11) != bmmask11) { 1125 if (modified == 0) { 1126 hammer2_chain_modify(chain, mtid, 0, 0); 1127 modified = 1; 1128 goto again; 1129 } 1130 if ((*bitmap & bmmask11) == bmmask00) { 1131 bmap->avail -= 1132 HAMMER2_FREEMAP_BLOCK_SIZE; 1133 bgsize += HAMMER2_FREEMAP_BLOCK_SIZE; 1134 } 1135 if (bmap->class == 0) 1136 bmap->class = class; 1137 *bitmap |= bmmask11; 1138 if (hammer2_debug & 0x0040) { 1139 kprintf("hammer2_freemap_recover: " 1140 "fixup type=%02x " 1141 "block=%016jx/%zd\n", 1142 bref->type, data_off, bytes); 1143 } 1144 } else { 1145 /* 1146 kprintf("hammer2_freemap_recover: good " 1147 "type=%02x block=%016jx/%zd\n", 1148 bref->type, data_off, bytes); 1149 */ 1150 } 1151 } 1152 #if 0 1153 /* 1154 * XXX this stuff doesn't work, avail is miscalculated and 1155 * code 10 means something else now. 1156 */ 1157 else if ((*bitmap & bmmask11) == bmmask11) { 1158 /* 1159 * Mayfree/Realfree request and bitmap is currently 1160 * marked as being fully allocated. 1161 */ 1162 if (!modified) { 1163 hammer2_chain_modify(chain, 0); 1164 modified = 1; 1165 goto again; 1166 } 1167 if (how == HAMMER2_FREEMAP_DOREALFREE) 1168 *bitmap &= ~bmmask11; 1169 else 1170 *bitmap = (*bitmap & ~bmmask11) | bmmask10; 1171 } else if ((*bitmap & bmmask11) == bmmask10) { 1172 /* 1173 * Mayfree/Realfree request and bitmap is currently 1174 * marked as being possibly freeable. 1175 */ 1176 if (how == HAMMER2_FREEMAP_DOREALFREE) { 1177 if (!modified) { 1178 hammer2_chain_modify(chain, 0); 1179 modified = 1; 1180 goto again; 1181 } 1182 *bitmap &= ~bmmask11; 1183 } 1184 } else { 1185 /* 1186 * 01 - Not implemented, currently illegal state 1187 * 00 - Not allocated at all, illegal free. 1188 */ 1189 panic("hammer2_freemap_adjust: " 1190 "Illegal state %08x(%08x)", 1191 *bitmap, *bitmap & bmmask11); 1192 } 1193 #endif 1194 --count; 1195 bmmask01 <<= 2; 1196 bmmask10 <<= 2; 1197 bmmask11 <<= 2; 1198 } 1199 #if HAMMER2_BMAP_ELEMENTS != 8 1200 #error "hammer2_freemap.c: HAMMER2_BMAP_ELEMENTS expected to be 8" 1201 #endif 1202 if (how == HAMMER2_FREEMAP_DOREALFREE && modified) { 1203 bmap->avail += 1 << radix; 1204 KKASSERT(bmap->avail <= HAMMER2_SEGSIZE); 1205 if (bmap->avail == HAMMER2_SEGSIZE && 1206 bmap->bitmapq[0] == 0 && 1207 bmap->bitmapq[1] == 0 && 1208 bmap->bitmapq[2] == 0 && 1209 bmap->bitmapq[3] == 0 && 1210 bmap->bitmapq[4] == 0 && 1211 bmap->bitmapq[5] == 0 && 1212 bmap->bitmapq[6] == 0 && 1213 bmap->bitmapq[7] == 0) { 1214 key = H2FMBASE(data_off, HAMMER2_FREEMAP_LEVEL0_RADIX); 1215 kprintf("Freeseg %016jx\n", (intmax_t)key); 1216 bmap->class = 0; 1217 } 1218 } 1219 1220 /* 1221 * chain->bref.check.freemap.bigmask (XXX) 1222 * 1223 * Setting bigmask is a hint to the allocation code that there might 1224 * be something allocatable. We also set this in recovery... it 1225 * doesn't hurt and we might want to use the hint for other validation 1226 * operations later on. 1227 * 1228 * We could calculate the largest possible allocation and set the 1229 * radii that could fit, but its easier just to set bigmask to -1. 1230 */ 1231 if (modified) { 1232 chain->bref.check.freemap.bigmask = -1; 1233 hmp->freemap_relaxed = 0; /* reset heuristic */ 1234 } 1235 1236 hammer2_chain_unlock(chain); 1237 hammer2_chain_drop(chain); 1238 done: 1239 hammer2_chain_unlock(parent); 1240 hammer2_chain_drop(parent); 1241 1242 if (bgsize) { 1243 hammer2_voldata_lock(hmp); 1244 hammer2_voldata_modify(hmp); 1245 hmp->voldata.allocator_free -= bgsize; 1246 hammer2_voldata_unlock(hmp); 1247 } 1248 } 1249 1250 /* 1251 * Validate the freemap, in three stages. 1252 * 1253 * stage-1 ALLOCATED -> POSSIBLY FREE 1254 * POSSIBLY FREE -> POSSIBLY FREE (type corrected) 1255 * 1256 * This transitions bitmap entries from ALLOCATED to POSSIBLY FREE. 1257 * The POSSIBLY FREE state does not mean that a block is actually free 1258 * and may be transitioned back to ALLOCATED in stage-2. 1259 * 1260 * This is typically done during normal filesystem operations when 1261 * something is deleted or a block is replaced. 1262 * 1263 * This is done by bulkfree in-bulk after a memory-bounded meta-data 1264 * scan to try to determine what might be freeable. 1265 * 1266 * This can be done unconditionally through a freemap scan when the 1267 * intention is to brute-force recover the proper state of the freemap. 1268 * 1269 * stage-2 POSSIBLY FREE -> ALLOCATED (scan metadata topology) 1270 * 1271 * This is done by bulkfree during a meta-data scan to ensure that 1272 * all blocks still actually allocated by the filesystem are marked 1273 * as such. 1274 * 1275 * NOTE! Live filesystem transitions to POSSIBLY FREE can occur while 1276 * the bulkfree stage-2 and stage-3 is running. The live filesystem 1277 * will use the alternative POSSIBLY FREE type (2) to prevent 1278 * stage-3 from improperly transitioning unvetted possibly-free 1279 * blocks to FREE. 1280 * 1281 * stage-3 POSSIBLY FREE (type 1) -> FREE (scan freemap) 1282 * 1283 * This is done by bulkfree to finalize POSSIBLY FREE states. 1284 * 1285 */ 1286