1 /* 2 * Copyright (c) 2011-2015 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 * and 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 /* 36 * This subsystem implements most of the core support functions for 37 * the hammer2_chain structure. 38 * 39 * Chains are the in-memory version on media objects (volume header, inodes, 40 * indirect blocks, data blocks, etc). Chains represent a portion of the 41 * HAMMER2 topology. 42 * 43 * Chains are no-longer delete-duplicated. Instead, the original in-memory 44 * chain will be moved along with its block reference (e.g. for things like 45 * renames, hardlink operations, modifications, etc), and will be indexed 46 * on a secondary list for flush handling instead of propagating a flag 47 * upward to the root. 48 * 49 * Concurrent front-end operations can still run against backend flushes 50 * as long as they do not cross the current flush boundary. An operation 51 * running above the current flush (in areas not yet flushed) can become 52 * part of the current flush while ano peration running below the current 53 * flush can become part of the next flush. 54 */ 55 #include <sys/cdefs.h> 56 #include <sys/param.h> 57 #include <sys/systm.h> 58 #include <sys/types.h> 59 #include <sys/lock.h> 60 #include <sys/kern_syscall.h> 61 #include <sys/uuid.h> 62 63 #include <crypto/sha2/sha2.h> 64 65 #include "hammer2.h" 66 67 static int hammer2_indirect_optimize; /* XXX SYSCTL */ 68 69 static hammer2_chain_t *hammer2_chain_create_indirect( 70 hammer2_chain_t *parent, 71 hammer2_key_t key, int keybits, 72 hammer2_tid_t mtid, int for_type, int *errorp); 73 static void hammer2_chain_drop_data(hammer2_chain_t *chain, int lastdrop); 74 static hammer2_chain_t *hammer2_combined_find( 75 hammer2_chain_t *parent, 76 hammer2_blockref_t *base, int count, 77 int *cache_indexp, hammer2_key_t *key_nextp, 78 hammer2_key_t key_beg, hammer2_key_t key_end, 79 hammer2_blockref_t **bresp); 80 81 /* 82 * Basic RBTree for chains (core->rbtree and core->dbtree). Chains cannot 83 * overlap in the RB trees. Deleted chains are moved from rbtree to either 84 * dbtree or to dbq. 85 * 86 * Chains in delete-duplicate sequences can always iterate through core_entry 87 * to locate the live version of the chain. 88 */ 89 RB_GENERATE(hammer2_chain_tree, hammer2_chain, rbnode, hammer2_chain_cmp); 90 91 int 92 hammer2_chain_cmp(hammer2_chain_t *chain1, hammer2_chain_t *chain2) 93 { 94 hammer2_key_t c1_beg; 95 hammer2_key_t c1_end; 96 hammer2_key_t c2_beg; 97 hammer2_key_t c2_end; 98 99 /* 100 * Compare chains. Overlaps are not supposed to happen and catch 101 * any software issues early we count overlaps as a match. 102 */ 103 c1_beg = chain1->bref.key; 104 c1_end = c1_beg + ((hammer2_key_t)1 << chain1->bref.keybits) - 1; 105 c2_beg = chain2->bref.key; 106 c2_end = c2_beg + ((hammer2_key_t)1 << chain2->bref.keybits) - 1; 107 108 if (c1_end < c2_beg) /* fully to the left */ 109 return(-1); 110 if (c1_beg > c2_end) /* fully to the right */ 111 return(1); 112 return(0); /* overlap (must not cross edge boundary) */ 113 } 114 115 static __inline 116 int 117 hammer2_isclusterable(hammer2_chain_t *chain) 118 { 119 if (hammer2_cluster_enable) { 120 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT || 121 chain->bref.type == HAMMER2_BREF_TYPE_INODE || 122 chain->bref.type == HAMMER2_BREF_TYPE_DATA) { 123 return(1); 124 } 125 } 126 return(0); 127 } 128 129 /* 130 * Make a chain visible to the flusher. The flusher needs to be able to 131 * do flushes of subdirectory chains or single files so it does a top-down 132 * recursion using the ONFLUSH flag for the recursion. It locates MODIFIED 133 * or UPDATE chains and flushes back up the chain to the volume root. 134 * 135 * This routine sets ONFLUSH upward until it hits the volume root. For 136 * simplicity we ignore PFSROOT boundaries whos rules can be complex. 137 * Extra ONFLUSH flagging doesn't hurt the filesystem. 138 */ 139 void 140 hammer2_chain_setflush(hammer2_chain_t *chain) 141 { 142 hammer2_chain_t *parent; 143 144 if ((chain->flags & HAMMER2_CHAIN_ONFLUSH) == 0) { 145 hammer2_spin_sh(&chain->core.spin); 146 while ((chain->flags & HAMMER2_CHAIN_ONFLUSH) == 0) { 147 atomic_set_int(&chain->flags, HAMMER2_CHAIN_ONFLUSH); 148 if ((parent = chain->parent) == NULL) 149 break; 150 hammer2_spin_sh(&parent->core.spin); 151 hammer2_spin_unsh(&chain->core.spin); 152 chain = parent; 153 } 154 hammer2_spin_unsh(&chain->core.spin); 155 } 156 } 157 158 /* 159 * Allocate a new disconnected chain element representing the specified 160 * bref. chain->refs is set to 1 and the passed bref is copied to 161 * chain->bref. chain->bytes is derived from the bref. 162 * 163 * chain->pmp inherits pmp unless the chain is an inode (other than the 164 * super-root inode). 165 * 166 * NOTE: Returns a referenced but unlocked (because there is no core) chain. 167 */ 168 hammer2_chain_t * 169 hammer2_chain_alloc(hammer2_dev_t *hmp, hammer2_pfs_t *pmp, 170 hammer2_blockref_t *bref) 171 { 172 hammer2_chain_t *chain; 173 u_int bytes = 1U << (int)(bref->data_off & HAMMER2_OFF_MASK_RADIX); 174 175 /* 176 * Construct the appropriate system structure. 177 */ 178 switch(bref->type) { 179 case HAMMER2_BREF_TYPE_INODE: 180 case HAMMER2_BREF_TYPE_INDIRECT: 181 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 182 case HAMMER2_BREF_TYPE_DATA: 183 case HAMMER2_BREF_TYPE_FREEMAP_LEAF: 184 /* 185 * Chain's are really only associated with the hmp but we 186 * maintain a pmp association for per-mount memory tracking 187 * purposes. The pmp can be NULL. 188 */ 189 chain = kmalloc(sizeof(*chain), hmp->mchain, M_WAITOK | M_ZERO); 190 break; 191 case HAMMER2_BREF_TYPE_VOLUME: 192 case HAMMER2_BREF_TYPE_FREEMAP: 193 /* 194 * Only hammer2_chain_bulksnap() calls this function with these 195 * types. 196 */ 197 chain = kmalloc(sizeof(*chain), hmp->mchain, M_WAITOK | M_ZERO); 198 break; 199 default: 200 chain = NULL; 201 panic("hammer2_chain_alloc: unrecognized blockref type: %d", 202 bref->type); 203 } 204 205 /* 206 * Initialize the new chain structure. pmp must be set to NULL for 207 * chains belonging to the super-root topology of a device mount. 208 */ 209 if (pmp == hmp->spmp) 210 chain->pmp = NULL; 211 else 212 chain->pmp = pmp; 213 chain->hmp = hmp; 214 chain->bref = *bref; 215 chain->bytes = bytes; 216 chain->refs = 1; 217 chain->flags = HAMMER2_CHAIN_ALLOCATED; 218 219 /* 220 * Set the PFS boundary flag if this chain represents a PFS root. 221 */ 222 if (bref->flags & HAMMER2_BREF_FLAG_PFSROOT) 223 chain->flags |= HAMMER2_CHAIN_PFSBOUNDARY; 224 hammer2_chain_core_init(chain); 225 226 return (chain); 227 } 228 229 /* 230 * Initialize a chain's core structure. This structure used to be allocated 231 * but is now embedded. 232 * 233 * The core is not locked. No additional refs on the chain are made. 234 * (trans) must not be NULL if (core) is not NULL. 235 */ 236 void 237 hammer2_chain_core_init(hammer2_chain_t *chain) 238 { 239 /* 240 * Fresh core under nchain (no multi-homing of ochain's 241 * sub-tree). 242 */ 243 RB_INIT(&chain->core.rbtree); /* live chains */ 244 hammer2_mtx_init(&chain->lock, "h2chain"); 245 } 246 247 /* 248 * Add a reference to a chain element, preventing its destruction. 249 * 250 * (can be called with spinlock held) 251 */ 252 void 253 hammer2_chain_ref(hammer2_chain_t *chain) 254 { 255 atomic_add_int(&chain->refs, 1); 256 #if 0 257 kprintf("REFC %p %d %08x\n", chain, chain->refs - 1, chain->flags); 258 print_backtrace(8); 259 #endif 260 } 261 262 /* 263 * Insert the chain in the core rbtree. 264 * 265 * Normal insertions are placed in the live rbtree. Insertion of a deleted 266 * chain is a special case used by the flush code that is placed on the 267 * unstaged deleted list to avoid confusing the live view. 268 */ 269 #define HAMMER2_CHAIN_INSERT_SPIN 0x0001 270 #define HAMMER2_CHAIN_INSERT_LIVE 0x0002 271 #define HAMMER2_CHAIN_INSERT_RACE 0x0004 272 273 static 274 int 275 hammer2_chain_insert(hammer2_chain_t *parent, hammer2_chain_t *chain, 276 int flags, int generation) 277 { 278 hammer2_chain_t *xchain; 279 int error = 0; 280 281 if (flags & HAMMER2_CHAIN_INSERT_SPIN) 282 hammer2_spin_ex(&parent->core.spin); 283 284 /* 285 * Interlocked by spinlock, check for race 286 */ 287 if ((flags & HAMMER2_CHAIN_INSERT_RACE) && 288 parent->core.generation != generation) { 289 error = EAGAIN; 290 goto failed; 291 } 292 293 /* 294 * Insert chain 295 */ 296 xchain = RB_INSERT(hammer2_chain_tree, &parent->core.rbtree, chain); 297 KASSERT(xchain == NULL, 298 ("hammer2_chain_insert: collision %p %p", chain, xchain)); 299 atomic_set_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE); 300 chain->parent = parent; 301 ++parent->core.chain_count; 302 ++parent->core.generation; /* XXX incs for _get() too, XXX */ 303 304 /* 305 * We have to keep track of the effective live-view blockref count 306 * so the create code knows when to push an indirect block. 307 */ 308 if (flags & HAMMER2_CHAIN_INSERT_LIVE) 309 atomic_add_int(&parent->core.live_count, 1); 310 failed: 311 if (flags & HAMMER2_CHAIN_INSERT_SPIN) 312 hammer2_spin_unex(&parent->core.spin); 313 return error; 314 } 315 316 /* 317 * Drop the caller's reference to the chain. When the ref count drops to 318 * zero this function will try to disassociate the chain from its parent and 319 * deallocate it, then recursely drop the parent using the implied ref 320 * from the chain's chain->parent. 321 */ 322 static hammer2_chain_t *hammer2_chain_lastdrop(hammer2_chain_t *chain); 323 324 void 325 hammer2_chain_drop(hammer2_chain_t *chain) 326 { 327 u_int refs; 328 u_int need = 0; 329 330 if (hammer2_debug & 0x200000) 331 Debugger("drop"); 332 #if 0 333 kprintf("DROP %p %d %08x\n", chain, chain->refs - 1, chain->flags); 334 print_backtrace(8); 335 #endif 336 337 if (chain->flags & HAMMER2_CHAIN_UPDATE) 338 ++need; 339 if (chain->flags & HAMMER2_CHAIN_MODIFIED) 340 ++need; 341 KKASSERT(chain->refs > need); 342 343 while (chain) { 344 refs = chain->refs; 345 cpu_ccfence(); 346 KKASSERT(refs > 0); 347 348 if (refs == 1) { 349 chain = hammer2_chain_lastdrop(chain); 350 } else { 351 if (atomic_cmpset_int(&chain->refs, refs, refs - 1)) 352 break; 353 /* retry the same chain */ 354 } 355 } 356 } 357 358 /* 359 * Safe handling of the 1->0 transition on chain. Returns a chain for 360 * recursive drop or NULL, possibly returning the same chain if the atomic 361 * op fails. 362 * 363 * Whem two chains need to be recursively dropped we use the chain 364 * we would otherwise free to placehold the additional chain. It's a bit 365 * convoluted but we can't just recurse without potentially blowing out 366 * the kernel stack. 367 * 368 * The chain cannot be freed if it has any children. 369 * 370 * The core spinlock is allowed nest child-to-parent (not parent-to-child). 371 */ 372 static 373 hammer2_chain_t * 374 hammer2_chain_lastdrop(hammer2_chain_t *chain) 375 { 376 hammer2_pfs_t *pmp; 377 hammer2_dev_t *hmp; 378 hammer2_chain_t *parent; 379 hammer2_chain_t *rdrop; 380 381 /* 382 * Spinlock the core and check to see if it is empty. If it is 383 * not empty we leave chain intact with refs == 0. The elements 384 * in core->rbtree are associated with other chains contemporary 385 * with ours but not with our chain directly. 386 */ 387 hammer2_spin_ex(&chain->core.spin); 388 389 /* 390 * We can't free non-stale chains with children until we are 391 * able to free the children because there might be a flush 392 * dependency. Flushes of stale children (which should also 393 * have their deleted flag set) short-cut recursive flush 394 * dependencies and can be freed here. Any flushes which run 395 * through stale children due to the flush synchronization 396 * point should have a FLUSH_* bit set in the chain and not 397 * reach lastdrop at this time. 398 * 399 * NOTE: We return (chain) on failure to retry. 400 */ 401 if (chain->core.chain_count) { 402 if (atomic_cmpset_int(&chain->refs, 1, 0)) { 403 hammer2_spin_unex(&chain->core.spin); 404 chain = NULL; /* success */ 405 } else { 406 hammer2_spin_unex(&chain->core.spin); 407 } 408 return(chain); 409 } 410 /* no chains left under us */ 411 412 /* 413 * chain->core has no children left so no accessors can get to our 414 * chain from there. Now we have to lock the parent core to interlock 415 * remaining possible accessors that might bump chain's refs before 416 * we can safely drop chain's refs with intent to free the chain. 417 */ 418 hmp = chain->hmp; 419 pmp = chain->pmp; /* can be NULL */ 420 rdrop = NULL; 421 422 /* 423 * Spinlock the parent and try to drop the last ref on chain. 424 * On success remove chain from its parent, otherwise return NULL. 425 * 426 * (normal core locks are top-down recursive but we define core 427 * spinlocks as bottom-up recursive, so this is safe). 428 */ 429 if ((parent = chain->parent) != NULL) { 430 hammer2_spin_ex(&parent->core.spin); 431 if (atomic_cmpset_int(&chain->refs, 1, 0) == 0) { 432 /* 1->0 transition failed */ 433 hammer2_spin_unex(&parent->core.spin); 434 hammer2_spin_unex(&chain->core.spin); 435 return(chain); /* retry */ 436 } 437 438 /* 439 * 1->0 transition successful, remove chain from its 440 * above core. 441 */ 442 if (chain->flags & HAMMER2_CHAIN_ONRBTREE) { 443 RB_REMOVE(hammer2_chain_tree, 444 &parent->core.rbtree, chain); 445 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE); 446 --parent->core.chain_count; 447 chain->parent = NULL; 448 } 449 450 /* 451 * If our chain was the last chain in the parent's core the 452 * core is now empty and its parent might have to be 453 * re-dropped if it has 0 refs. 454 */ 455 if (parent->core.chain_count == 0) { 456 rdrop = parent; 457 if (atomic_cmpset_int(&rdrop->refs, 0, 1) == 0) { 458 rdrop = NULL; 459 } 460 } 461 hammer2_spin_unex(&parent->core.spin); 462 parent = NULL; /* safety */ 463 } 464 465 /* 466 * Successful 1->0 transition and the chain can be destroyed now. 467 * 468 * We still have the core spinlock, and core's chain_count is 0. 469 * Any parent spinlock is gone. 470 */ 471 hammer2_spin_unex(&chain->core.spin); 472 KKASSERT(RB_EMPTY(&chain->core.rbtree) && 473 chain->core.chain_count == 0); 474 475 /* 476 * All spin locks are gone, finish freeing stuff. 477 */ 478 KKASSERT((chain->flags & (HAMMER2_CHAIN_UPDATE | 479 HAMMER2_CHAIN_MODIFIED)) == 0); 480 hammer2_chain_drop_data(chain, 1); 481 482 KKASSERT(chain->dio == NULL); 483 484 /* 485 * Once chain resources are gone we can use the now dead chain 486 * structure to placehold what might otherwise require a recursive 487 * drop, because we have potentially two things to drop and can only 488 * return one directly. 489 */ 490 if (chain->flags & HAMMER2_CHAIN_ALLOCATED) { 491 chain->flags &= ~HAMMER2_CHAIN_ALLOCATED; 492 chain->hmp = NULL; 493 kfree(chain, hmp->mchain); 494 } 495 496 /* 497 * Possible chaining loop when parent re-drop needed. 498 */ 499 return(rdrop); 500 } 501 502 /* 503 * On either last lock release or last drop 504 */ 505 static void 506 hammer2_chain_drop_data(hammer2_chain_t *chain, int lastdrop) 507 { 508 /*hammer2_dev_t *hmp = chain->hmp;*/ 509 510 switch(chain->bref.type) { 511 case HAMMER2_BREF_TYPE_VOLUME: 512 case HAMMER2_BREF_TYPE_FREEMAP: 513 if (lastdrop) 514 chain->data = NULL; 515 break; 516 default: 517 KKASSERT(chain->data == NULL); 518 break; 519 } 520 } 521 522 /* 523 * Lock a referenced chain element, acquiring its data with I/O if necessary, 524 * and specify how you would like the data to be resolved. 525 * 526 * If an I/O or other fatal error occurs, chain->error will be set to non-zero. 527 * 528 * The lock is allowed to recurse, multiple locking ops will aggregate 529 * the requested resolve types. Once data is assigned it will not be 530 * removed until the last unlock. 531 * 532 * HAMMER2_RESOLVE_NEVER - Do not resolve the data element. 533 * (typically used to avoid device/logical buffer 534 * aliasing for data) 535 * 536 * HAMMER2_RESOLVE_MAYBE - Do not resolve data elements for chains in 537 * the INITIAL-create state (indirect blocks only). 538 * 539 * Do not resolve data elements for DATA chains. 540 * (typically used to avoid device/logical buffer 541 * aliasing for data) 542 * 543 * HAMMER2_RESOLVE_ALWAYS- Always resolve the data element. 544 * 545 * HAMMER2_RESOLVE_SHARED- (flag) The chain is locked shared, otherwise 546 * it will be locked exclusive. 547 * 548 * NOTE: Embedded elements (volume header, inodes) are always resolved 549 * regardless. 550 * 551 * NOTE: Specifying HAMMER2_RESOLVE_ALWAYS on a newly-created non-embedded 552 * element will instantiate and zero its buffer, and flush it on 553 * release. 554 * 555 * NOTE: (data) elements are normally locked RESOLVE_NEVER or RESOLVE_MAYBE 556 * so as not to instantiate a device buffer, which could alias against 557 * a logical file buffer. However, if ALWAYS is specified the 558 * device buffer will be instantiated anyway. 559 * 560 * WARNING! This function blocks on I/O if data needs to be fetched. This 561 * blocking can run concurrent with other compatible lock holders 562 * who do not need data returning. The lock is not upgraded to 563 * exclusive during a data fetch, a separate bit is used to 564 * interlock I/O. However, an exclusive lock holder can still count 565 * on being interlocked against an I/O fetch managed by a shared 566 * lock holder. 567 */ 568 void 569 hammer2_chain_lock(hammer2_chain_t *chain, int how) 570 { 571 /* 572 * Ref and lock the element. Recursive locks are allowed. 573 */ 574 KKASSERT(chain->refs > 0); 575 atomic_add_int(&chain->lockcnt, 1); 576 577 /* 578 * Get the appropriate lock. 579 */ 580 if (how & HAMMER2_RESOLVE_SHARED) 581 hammer2_mtx_sh(&chain->lock); 582 else 583 hammer2_mtx_ex(&chain->lock); 584 585 /* 586 * If we already have a valid data pointer no further action is 587 * necessary. 588 */ 589 if (chain->data) 590 return; 591 592 /* 593 * Do we have to resolve the data? 594 */ 595 switch(how & HAMMER2_RESOLVE_MASK) { 596 case HAMMER2_RESOLVE_NEVER: 597 return; 598 case HAMMER2_RESOLVE_MAYBE: 599 if (chain->flags & HAMMER2_CHAIN_INITIAL) 600 return; 601 if (chain->bref.type == HAMMER2_BREF_TYPE_DATA) 602 return; 603 #if 0 604 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) 605 return; 606 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) 607 return; 608 #endif 609 /* fall through */ 610 case HAMMER2_RESOLVE_ALWAYS: 611 default: 612 break; 613 } 614 615 /* 616 * Caller requires data 617 */ 618 hammer2_chain_load_data(chain); 619 } 620 621 /* 622 * Issue I/O and install chain->data. Caller must hold a chain lock, lock 623 * may be of any type. 624 * 625 * Once chain->data is set it cannot be disposed of until all locks are 626 * released. 627 */ 628 void 629 hammer2_chain_load_data(hammer2_chain_t *chain) 630 { 631 hammer2_blockref_t *bref; 632 hammer2_dev_t *hmp; 633 char *bdata; 634 int error; 635 636 /* 637 * Degenerate case, data already present. 638 */ 639 if (chain->data) 640 return; 641 642 hmp = chain->hmp; 643 KKASSERT(hmp != NULL); 644 645 /* 646 * Gain the IOINPROG bit, interlocked block. 647 */ 648 for (;;) { 649 u_int oflags; 650 u_int nflags; 651 652 oflags = chain->flags; 653 cpu_ccfence(); 654 if (oflags & HAMMER2_CHAIN_IOINPROG) { 655 nflags = oflags | HAMMER2_CHAIN_IOSIGNAL; 656 tsleep_interlock(&chain->flags, 0); 657 if (atomic_cmpset_int(&chain->flags, oflags, nflags)) { 658 tsleep(&chain->flags, PINTERLOCKED, 659 "h2iocw", 0); 660 } 661 /* retry */ 662 } else { 663 nflags = oflags | HAMMER2_CHAIN_IOINPROG; 664 if (atomic_cmpset_int(&chain->flags, oflags, nflags)) { 665 break; 666 } 667 /* retry */ 668 } 669 } 670 671 /* 672 * We own CHAIN_IOINPROG 673 * 674 * Degenerate case if we raced another load. 675 */ 676 if (chain->data) 677 goto done; 678 679 /* 680 * We must resolve to a device buffer, either by issuing I/O or 681 * by creating a zero-fill element. We do not mark the buffer 682 * dirty when creating a zero-fill element (the hammer2_chain_modify() 683 * API must still be used to do that). 684 * 685 * The device buffer is variable-sized in powers of 2 down 686 * to HAMMER2_MIN_ALLOC (typically 1K). A 64K physical storage 687 * chunk always contains buffers of the same size. (XXX) 688 * 689 * The minimum physical IO size may be larger than the variable 690 * block size. 691 */ 692 bref = &chain->bref; 693 694 /* 695 * The getblk() optimization can only be used on newly created 696 * elements if the physical block size matches the request. 697 */ 698 if (chain->flags & HAMMER2_CHAIN_INITIAL) { 699 error = hammer2_io_new(hmp, bref->data_off, chain->bytes, 700 &chain->dio); 701 } else { 702 error = hammer2_io_bread(hmp, bref->data_off, chain->bytes, 703 &chain->dio); 704 hammer2_adjreadcounter(&chain->bref, chain->bytes); 705 } 706 if (error) { 707 chain->error = HAMMER2_ERROR_IO; 708 kprintf("hammer2_chain_lock: I/O error %016jx: %d\n", 709 (intmax_t)bref->data_off, error); 710 hammer2_io_bqrelse(&chain->dio); 711 goto done; 712 } 713 chain->error = 0; 714 715 /* 716 * NOTE: A locked chain's data cannot be modified without first 717 * calling hammer2_chain_modify(). 718 */ 719 720 /* 721 * Clear INITIAL. In this case we used io_new() and the buffer has 722 * been zero'd and marked dirty. 723 */ 724 bdata = hammer2_io_data(chain->dio, chain->bref.data_off); 725 if (chain->flags & HAMMER2_CHAIN_INITIAL) { 726 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 727 chain->bref.flags |= HAMMER2_BREF_FLAG_ZERO; 728 } else if (chain->flags & HAMMER2_CHAIN_MODIFIED) { 729 /* 730 * check data not currently synchronized due to 731 * modification. XXX assumes data stays in the buffer 732 * cache, which might not be true (need biodep on flush 733 * to calculate crc? or simple crc?). 734 */ 735 } else { 736 if (hammer2_chain_testcheck(chain, bdata) == 0) { 737 kprintf("chain %016jx.%02x meth=%02x " 738 "CHECK FAIL %08x (flags=%08x)\n", 739 chain->bref.data_off, 740 chain->bref.type, 741 chain->bref.methods, 742 hammer2_icrc32(bdata, chain->bytes), 743 chain->flags); 744 chain->error = HAMMER2_ERROR_CHECK; 745 } 746 } 747 748 /* 749 * Setup the data pointer, either pointing it to an embedded data 750 * structure and copying the data from the buffer, or pointing it 751 * into the buffer. 752 * 753 * The buffer is not retained when copying to an embedded data 754 * structure in order to avoid potential deadlocks or recursions 755 * on the same physical buffer. 756 * 757 * WARNING! Other threads can start using the data the instant we 758 * set chain->data non-NULL. 759 */ 760 switch (bref->type) { 761 case HAMMER2_BREF_TYPE_VOLUME: 762 case HAMMER2_BREF_TYPE_FREEMAP: 763 /* 764 * Copy data from bp to embedded buffer 765 */ 766 panic("hammer2_chain_lock: called on unresolved volume header"); 767 break; 768 case HAMMER2_BREF_TYPE_INODE: 769 case HAMMER2_BREF_TYPE_FREEMAP_LEAF: 770 case HAMMER2_BREF_TYPE_INDIRECT: 771 case HAMMER2_BREF_TYPE_DATA: 772 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 773 default: 774 /* 775 * Point data at the device buffer and leave dio intact. 776 */ 777 chain->data = (void *)bdata; 778 break; 779 } 780 781 /* 782 * Release HAMMER2_CHAIN_IOINPROG and signal waiters if requested. 783 */ 784 done: 785 for (;;) { 786 u_int oflags; 787 u_int nflags; 788 789 oflags = chain->flags; 790 nflags = oflags & ~(HAMMER2_CHAIN_IOINPROG | 791 HAMMER2_CHAIN_IOSIGNAL); 792 KKASSERT(oflags & HAMMER2_CHAIN_IOINPROG); 793 if (atomic_cmpset_int(&chain->flags, oflags, nflags)) { 794 if (oflags & HAMMER2_CHAIN_IOSIGNAL) 795 wakeup(&chain->flags); 796 break; 797 } 798 } 799 } 800 801 /* 802 * Unlock and deref a chain element. 803 * 804 * On the last lock release any non-embedded data (chain->dio) will be 805 * retired. 806 */ 807 void 808 hammer2_chain_unlock(hammer2_chain_t *chain) 809 { 810 hammer2_mtx_state_t ostate; 811 long *counterp; 812 u_int lockcnt; 813 814 /* 815 * If multiple locks are present (or being attempted) on this 816 * particular chain we can just unlock, drop refs, and return. 817 * 818 * Otherwise fall-through on the 1->0 transition. 819 */ 820 for (;;) { 821 lockcnt = chain->lockcnt; 822 KKASSERT(lockcnt > 0); 823 cpu_ccfence(); 824 if (lockcnt > 1) { 825 if (atomic_cmpset_int(&chain->lockcnt, 826 lockcnt, lockcnt - 1)) { 827 hammer2_mtx_unlock(&chain->lock); 828 return; 829 } 830 } else { 831 if (atomic_cmpset_int(&chain->lockcnt, 1, 0)) 832 break; 833 } 834 /* retry */ 835 } 836 837 /* 838 * On the 1->0 transition we upgrade the core lock (if necessary) 839 * to exclusive for terminal processing. If after upgrading we find 840 * that lockcnt is non-zero, another thread is racing us and will 841 * handle the unload for us later on, so just cleanup and return 842 * leaving the data/io intact 843 * 844 * Otherwise if lockcnt is still 0 it is possible for it to become 845 * non-zero and race, but since we hold the core->lock exclusively 846 * all that will happen is that the chain will be reloaded after we 847 * unload it. 848 */ 849 ostate = hammer2_mtx_upgrade(&chain->lock); 850 if (chain->lockcnt) { 851 hammer2_mtx_unlock(&chain->lock); 852 return; 853 } 854 855 /* 856 * Shortcut the case if the data is embedded or not resolved. 857 * 858 * Do NOT NULL out chain->data (e.g. inode data), it might be 859 * dirty. 860 */ 861 if (chain->dio == NULL) { 862 if ((chain->flags & HAMMER2_CHAIN_MODIFIED) == 0) 863 hammer2_chain_drop_data(chain, 0); 864 hammer2_mtx_unlock(&chain->lock); 865 return; 866 } 867 868 /* 869 * Statistics 870 */ 871 if (hammer2_io_isdirty(chain->dio)) { 872 switch(chain->bref.type) { 873 case HAMMER2_BREF_TYPE_DATA: 874 counterp = &hammer2_iod_file_write; 875 break; 876 case HAMMER2_BREF_TYPE_INODE: 877 counterp = &hammer2_iod_meta_write; 878 break; 879 case HAMMER2_BREF_TYPE_INDIRECT: 880 counterp = &hammer2_iod_indr_write; 881 break; 882 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 883 case HAMMER2_BREF_TYPE_FREEMAP_LEAF: 884 counterp = &hammer2_iod_fmap_write; 885 break; 886 default: 887 counterp = &hammer2_iod_volu_write; 888 break; 889 } 890 *counterp += chain->bytes; 891 } 892 893 /* 894 * Clean out the dio. 895 * 896 * NOTE: Freemap leaf's use reserved blocks and thus no aliasing 897 * is possible. 898 */ 899 chain->data = NULL; 900 hammer2_io_bqrelse(&chain->dio); 901 hammer2_mtx_unlock(&chain->lock); 902 } 903 904 /* 905 * This counts the number of live blockrefs in a block array and 906 * also calculates the point at which all remaining blockrefs are empty. 907 * This routine can only be called on a live chain (DUPLICATED flag not set). 908 * 909 * NOTE: Flag is not set until after the count is complete, allowing 910 * callers to test the flag without holding the spinlock. 911 * 912 * NOTE: If base is NULL the related chain is still in the INITIAL 913 * state and there are no blockrefs to count. 914 * 915 * NOTE: live_count may already have some counts accumulated due to 916 * creation and deletion and could even be initially negative. 917 */ 918 void 919 hammer2_chain_countbrefs(hammer2_chain_t *chain, 920 hammer2_blockref_t *base, int count) 921 { 922 hammer2_spin_ex(&chain->core.spin); 923 if ((chain->flags & HAMMER2_CHAIN_COUNTEDBREFS) == 0) { 924 if (base) { 925 while (--count >= 0) { 926 if (base[count].type) 927 break; 928 } 929 chain->core.live_zero = count + 1; 930 while (count >= 0) { 931 if (base[count].type) 932 atomic_add_int(&chain->core.live_count, 933 1); 934 --count; 935 } 936 } else { 937 chain->core.live_zero = 0; 938 } 939 /* else do not modify live_count */ 940 atomic_set_int(&chain->flags, HAMMER2_CHAIN_COUNTEDBREFS); 941 } 942 hammer2_spin_unex(&chain->core.spin); 943 } 944 945 /* 946 * Resize the chain's physical storage allocation in-place. This function does 947 * not adjust the data pointer and must be followed by (typically) a 948 * hammer2_chain_modify() call to copy any old data over and adjust the 949 * data pointer. 950 * 951 * Chains can be resized smaller without reallocating the storage. Resizing 952 * larger will reallocate the storage. Excess or prior storage is reclaimed 953 * asynchronously at a later time. 954 * 955 * Must be passed an exclusively locked parent and chain. 956 * 957 * This function is mostly used with DATA blocks locked RESOLVE_NEVER in order 958 * to avoid instantiating a device buffer that conflicts with the vnode data 959 * buffer. However, because H2 can compress or encrypt data, the chain may 960 * have a dio assigned to it in those situations, and they do not conflict. 961 * 962 * XXX return error if cannot resize. 963 */ 964 void 965 hammer2_chain_resize(hammer2_inode_t *ip, 966 hammer2_chain_t *parent, hammer2_chain_t *chain, 967 hammer2_tid_t mtid, hammer2_off_t dedup_off, 968 int nradix, int flags) 969 { 970 hammer2_dev_t *hmp; 971 size_t obytes; 972 size_t nbytes; 973 974 hmp = chain->hmp; 975 976 /* 977 * Only data and indirect blocks can be resized for now. 978 * (The volu root, inodes, and freemap elements use a fixed size). 979 */ 980 KKASSERT(chain != &hmp->vchain); 981 KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_DATA || 982 chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT); 983 KKASSERT(chain->parent == parent); 984 985 /* 986 * Nothing to do if the element is already the proper size 987 */ 988 obytes = chain->bytes; 989 nbytes = 1U << nradix; 990 if (obytes == nbytes) 991 return; 992 993 /* 994 * Make sure the old data is instantiated so we can copy it. If this 995 * is a data block, the device data may be superfluous since the data 996 * might be in a logical block, but compressed or encrypted data is 997 * another matter. 998 * 999 * NOTE: The modify will set BMAPUPD for us if BMAPPED is set. 1000 */ 1001 hammer2_chain_modify(chain, mtid, dedup_off, 0); 1002 1003 /* 1004 * Relocate the block, even if making it smaller (because different 1005 * block sizes may be in different regions). 1006 * 1007 * (data blocks only, we aren't copying the storage here). 1008 */ 1009 hammer2_freemap_alloc(chain, nbytes); 1010 chain->bytes = nbytes; 1011 /*ip->delta_dcount += (ssize_t)(nbytes - obytes);*/ /* XXX atomic */ 1012 1013 /* 1014 * We don't want the followup chain_modify() to try to copy data 1015 * from the old (wrong-sized) buffer. It won't know how much to 1016 * copy. This case should only occur during writes when the 1017 * originator already has the data to write in-hand. 1018 */ 1019 if (chain->dio) { 1020 KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_DATA); 1021 hammer2_io_brelse(&chain->dio); 1022 chain->data = NULL; 1023 } 1024 } 1025 1026 /* 1027 * Set the chain modified so its data can be changed by the caller. 1028 * 1029 * Sets bref.modify_tid to mtid only if mtid != 0. Note that bref.modify_tid 1030 * is a CLC (cluster level change) field and is not updated by parent 1031 * propagation during a flush. 1032 * 1033 * If the caller passes a non-zero dedup_off we assign data_off to that 1034 * instead of allocating a ne block. Caller must not modify the data already 1035 * present at the target offset. 1036 */ 1037 void 1038 hammer2_chain_modify(hammer2_chain_t *chain, hammer2_tid_t mtid, 1039 hammer2_off_t dedup_off, int flags) 1040 { 1041 hammer2_blockref_t obref; 1042 hammer2_dev_t *hmp; 1043 hammer2_io_t *dio; 1044 int error; 1045 int wasinitial; 1046 int newmod; 1047 char *bdata; 1048 1049 hmp = chain->hmp; 1050 obref = chain->bref; 1051 KKASSERT((chain->flags & HAMMER2_CHAIN_FICTITIOUS) == 0); 1052 1053 /* 1054 * Data is not optional for freemap chains (we must always be sure 1055 * to copy the data on COW storage allocations). 1056 */ 1057 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE || 1058 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) { 1059 KKASSERT((chain->flags & HAMMER2_CHAIN_INITIAL) || 1060 (flags & HAMMER2_MODIFY_OPTDATA) == 0); 1061 } 1062 1063 /* 1064 * Data must be resolved if already assigned, unless explicitly 1065 * flagged otherwise. 1066 */ 1067 if (chain->data == NULL && (flags & HAMMER2_MODIFY_OPTDATA) == 0 && 1068 (chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX)) { 1069 hammer2_chain_load_data(chain); 1070 } 1071 1072 /* 1073 * Set MODIFIED to indicate that the chain has been modified. 1074 * Set UPDATE to ensure that the blockref is updated in the parent. 1075 */ 1076 if ((chain->flags & (HAMMER2_CHAIN_DEDUP | HAMMER2_CHAIN_MODIFIED)) == 1077 (HAMMER2_CHAIN_DEDUP | HAMMER2_CHAIN_MODIFIED)) { 1078 newmod = 1; 1079 } else if ((chain->flags & HAMMER2_CHAIN_MODIFIED) == 0) { 1080 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MODIFIED); 1081 hammer2_chain_ref(chain); 1082 hammer2_pfs_memory_inc(chain->pmp); /* can be NULL */ 1083 newmod = 1; 1084 } else { 1085 newmod = 0; 1086 } 1087 if ((chain->flags & HAMMER2_CHAIN_UPDATE) == 0) { 1088 atomic_set_int(&chain->flags, HAMMER2_CHAIN_UPDATE); 1089 hammer2_chain_ref(chain); 1090 } 1091 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_DEDUP); 1092 1093 /* 1094 * The modification or re-modification requires an allocation and 1095 * possible COW. 1096 * 1097 * If dedup_off is non-zero, caller already has a data offset 1098 * containing the caller's desired data. The dedup offset is 1099 * allowed to be in a partially free state and we must be sure 1100 * to reset it to a fully allocated state to force two bulkfree 1101 * passes to free it again. 1102 * 1103 * XXX can a chain already be marked MODIFIED without a data 1104 * assignment? If not, assert here instead of testing the case. 1105 */ 1106 if (chain != &hmp->vchain && chain != &hmp->fchain) { 1107 if ((chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX) == 0 || 1108 newmod 1109 ) { 1110 if (dedup_off) { 1111 chain->bref.data_off = dedup_off; 1112 atomic_set_int(&chain->flags, 1113 HAMMER2_CHAIN_DEDUP); 1114 hammer2_freemap_adjust(hmp, &chain->bref, 1115 HAMMER2_FREEMAP_DORECOVER); 1116 } else { 1117 hammer2_freemap_alloc(chain, chain->bytes); 1118 } 1119 /* XXX failed allocation */ 1120 } 1121 } 1122 1123 /* 1124 * Update mirror_tid and modify_tid. modify_tid is only updated 1125 * if not passed as zero (during flushes, parent propagation passes 1126 * the value 0). 1127 * 1128 * NOTE: chain->pmp could be the device spmp. 1129 */ 1130 chain->bref.mirror_tid = hmp->voldata.mirror_tid + 1; 1131 if (mtid) 1132 chain->bref.modify_tid = mtid; 1133 1134 /* 1135 * Set BMAPUPD to tell the flush code that an existing blockmap entry 1136 * requires updating as well as to tell the delete code that the 1137 * chain's blockref might not exactly match (in terms of physical size 1138 * or block offset) the one in the parent's blocktable. The base key 1139 * of course will still match. 1140 */ 1141 if (chain->flags & HAMMER2_CHAIN_BMAPPED) 1142 atomic_set_int(&chain->flags, HAMMER2_CHAIN_BMAPUPD); 1143 1144 /* 1145 * Short-cut data blocks which the caller does not need an actual 1146 * data reference to (aka OPTDATA), as long as the chain does not 1147 * already have a data pointer to the data. This generally means 1148 * that the modifications are being done via the logical buffer cache. 1149 * The INITIAL flag relates only to the device data buffer and thus 1150 * remains unchange in this situation. 1151 */ 1152 if (chain->bref.type == HAMMER2_BREF_TYPE_DATA && 1153 (flags & HAMMER2_MODIFY_OPTDATA) && 1154 chain->data == NULL) { 1155 goto skip2; 1156 } 1157 1158 /* 1159 * Clearing the INITIAL flag (for indirect blocks) indicates that 1160 * we've processed the uninitialized storage allocation. 1161 * 1162 * If this flag is already clear we are likely in a copy-on-write 1163 * situation but we have to be sure NOT to bzero the storage if 1164 * no data is present. 1165 */ 1166 if (chain->flags & HAMMER2_CHAIN_INITIAL) { 1167 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1168 wasinitial = 1; 1169 } else { 1170 wasinitial = 0; 1171 } 1172 1173 /* 1174 * Instantiate data buffer and possibly execute COW operation 1175 */ 1176 switch(chain->bref.type) { 1177 case HAMMER2_BREF_TYPE_VOLUME: 1178 case HAMMER2_BREF_TYPE_FREEMAP: 1179 /* 1180 * The data is embedded, no copy-on-write operation is 1181 * needed. 1182 */ 1183 KKASSERT(chain->dio == NULL); 1184 break; 1185 case HAMMER2_BREF_TYPE_INODE: 1186 case HAMMER2_BREF_TYPE_FREEMAP_LEAF: 1187 case HAMMER2_BREF_TYPE_DATA: 1188 case HAMMER2_BREF_TYPE_INDIRECT: 1189 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 1190 /* 1191 * Perform the copy-on-write operation 1192 * 1193 * zero-fill or copy-on-write depending on whether 1194 * chain->data exists or not and set the dirty state for 1195 * the new buffer. hammer2_io_new() will handle the 1196 * zero-fill. 1197 * 1198 * If a dedup_off was supplied this is an existing block 1199 * and no COW, copy, or further modification is required. 1200 */ 1201 KKASSERT(chain != &hmp->vchain && chain != &hmp->fchain); 1202 1203 if (wasinitial && dedup_off == 0) { 1204 error = hammer2_io_new(hmp, chain->bref.data_off, 1205 chain->bytes, &dio); 1206 } else { 1207 error = hammer2_io_bread(hmp, chain->bref.data_off, 1208 chain->bytes, &dio); 1209 } 1210 hammer2_adjreadcounter(&chain->bref, chain->bytes); 1211 1212 /* 1213 * If an I/O error occurs make sure callers cannot accidently 1214 * modify the old buffer's contents and corrupt the filesystem. 1215 */ 1216 if (error) { 1217 kprintf("hammer2_chain_modify: hmp=%p I/O error\n", 1218 hmp); 1219 chain->error = HAMMER2_ERROR_IO; 1220 hammer2_io_brelse(&dio); 1221 hammer2_io_brelse(&chain->dio); 1222 chain->data = NULL; 1223 break; 1224 } 1225 chain->error = 0; 1226 bdata = hammer2_io_data(dio, chain->bref.data_off); 1227 1228 if (chain->data) { 1229 /* 1230 * COW (unless a dedup). 1231 */ 1232 KKASSERT(chain->dio != NULL); 1233 if (chain->data != (void *)bdata && dedup_off == 0) { 1234 bcopy(chain->data, bdata, chain->bytes); 1235 } 1236 } else if (wasinitial == 0) { 1237 /* 1238 * We have a problem. We were asked to COW but 1239 * we don't have any data to COW with! 1240 */ 1241 panic("hammer2_chain_modify: having a COW %p\n", 1242 chain); 1243 } 1244 1245 /* 1246 * Retire the old buffer, replace with the new. Dirty or 1247 * redirty the new buffer. 1248 * 1249 * WARNING! The system buffer cache may have already flushed 1250 * the buffer, so we must be sure to [re]dirty it 1251 * for further modification. 1252 * 1253 * If dedup_off was supplied, the caller is not 1254 * expected to make any further modification to the 1255 * buffer. 1256 */ 1257 if (chain->dio) 1258 hammer2_io_bqrelse(&chain->dio); 1259 chain->data = (void *)bdata; 1260 chain->dio = dio; 1261 if (dedup_off == 0) 1262 hammer2_io_setdirty(dio); 1263 break; 1264 default: 1265 panic("hammer2_chain_modify: illegal non-embedded type %d", 1266 chain->bref.type); 1267 break; 1268 1269 } 1270 skip2: 1271 /* 1272 * setflush on parent indicating that the parent must recurse down 1273 * to us. Do not call on chain itself which might already have it 1274 * set. 1275 */ 1276 if (chain->parent) 1277 hammer2_chain_setflush(chain->parent); 1278 } 1279 1280 /* 1281 * Modify the chain associated with an inode. 1282 */ 1283 void 1284 hammer2_chain_modify_ip(hammer2_inode_t *ip, hammer2_chain_t *chain, 1285 hammer2_tid_t mtid, int flags) 1286 { 1287 hammer2_inode_modify(ip); 1288 hammer2_chain_modify(chain, mtid, 0, flags); 1289 } 1290 1291 /* 1292 * Volume header data locks 1293 */ 1294 void 1295 hammer2_voldata_lock(hammer2_dev_t *hmp) 1296 { 1297 lockmgr(&hmp->vollk, LK_EXCLUSIVE); 1298 } 1299 1300 void 1301 hammer2_voldata_unlock(hammer2_dev_t *hmp) 1302 { 1303 lockmgr(&hmp->vollk, LK_RELEASE); 1304 } 1305 1306 void 1307 hammer2_voldata_modify(hammer2_dev_t *hmp) 1308 { 1309 if ((hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) == 0) { 1310 atomic_set_int(&hmp->vchain.flags, HAMMER2_CHAIN_MODIFIED); 1311 hammer2_chain_ref(&hmp->vchain); 1312 hammer2_pfs_memory_inc(hmp->vchain.pmp); 1313 } 1314 } 1315 1316 /* 1317 * This function returns the chain at the nearest key within the specified 1318 * range. The returned chain will be referenced but not locked. 1319 * 1320 * This function will recurse through chain->rbtree as necessary and will 1321 * return a *key_nextp suitable for iteration. *key_nextp is only set if 1322 * the iteration value is less than the current value of *key_nextp. 1323 * 1324 * The caller should use (*key_nextp) to calculate the actual range of 1325 * the returned element, which will be (key_beg to *key_nextp - 1), because 1326 * there might be another element which is superior to the returned element 1327 * and overlaps it. 1328 * 1329 * (*key_nextp) can be passed as key_beg in an iteration only while non-NULL 1330 * chains continue to be returned. On EOF (*key_nextp) may overflow since 1331 * it will wind up being (key_end + 1). 1332 * 1333 * WARNING! Must be called with child's spinlock held. Spinlock remains 1334 * held through the operation. 1335 */ 1336 struct hammer2_chain_find_info { 1337 hammer2_chain_t *best; 1338 hammer2_key_t key_beg; 1339 hammer2_key_t key_end; 1340 hammer2_key_t key_next; 1341 }; 1342 1343 static int hammer2_chain_find_cmp(hammer2_chain_t *child, void *data); 1344 static int hammer2_chain_find_callback(hammer2_chain_t *child, void *data); 1345 1346 static 1347 hammer2_chain_t * 1348 hammer2_chain_find(hammer2_chain_t *parent, hammer2_key_t *key_nextp, 1349 hammer2_key_t key_beg, hammer2_key_t key_end) 1350 { 1351 struct hammer2_chain_find_info info; 1352 1353 info.best = NULL; 1354 info.key_beg = key_beg; 1355 info.key_end = key_end; 1356 info.key_next = *key_nextp; 1357 1358 RB_SCAN(hammer2_chain_tree, &parent->core.rbtree, 1359 hammer2_chain_find_cmp, hammer2_chain_find_callback, 1360 &info); 1361 *key_nextp = info.key_next; 1362 #if 0 1363 kprintf("chain_find %p %016jx:%016jx next=%016jx\n", 1364 parent, key_beg, key_end, *key_nextp); 1365 #endif 1366 1367 return (info.best); 1368 } 1369 1370 static 1371 int 1372 hammer2_chain_find_cmp(hammer2_chain_t *child, void *data) 1373 { 1374 struct hammer2_chain_find_info *info = data; 1375 hammer2_key_t child_beg; 1376 hammer2_key_t child_end; 1377 1378 child_beg = child->bref.key; 1379 child_end = child_beg + ((hammer2_key_t)1 << child->bref.keybits) - 1; 1380 1381 if (child_end < info->key_beg) 1382 return(-1); 1383 if (child_beg > info->key_end) 1384 return(1); 1385 return(0); 1386 } 1387 1388 static 1389 int 1390 hammer2_chain_find_callback(hammer2_chain_t *child, void *data) 1391 { 1392 struct hammer2_chain_find_info *info = data; 1393 hammer2_chain_t *best; 1394 hammer2_key_t child_end; 1395 1396 /* 1397 * WARNING! Do not discard DUPLICATED chains, it is possible that 1398 * we are catching an insertion half-way done. If a 1399 * duplicated chain turns out to be the best choice the 1400 * caller will re-check its flags after locking it. 1401 * 1402 * WARNING! Layerq is scanned forwards, exact matches should keep 1403 * the existing info->best. 1404 */ 1405 if ((best = info->best) == NULL) { 1406 /* 1407 * No previous best. Assign best 1408 */ 1409 info->best = child; 1410 } else if (best->bref.key <= info->key_beg && 1411 child->bref.key <= info->key_beg) { 1412 /* 1413 * Illegal overlap. 1414 */ 1415 KKASSERT(0); 1416 /*info->best = child;*/ 1417 } else if (child->bref.key < best->bref.key) { 1418 /* 1419 * Child has a nearer key and best is not flush with key_beg. 1420 * Set best to child. Truncate key_next to the old best key. 1421 */ 1422 info->best = child; 1423 if (info->key_next > best->bref.key || info->key_next == 0) 1424 info->key_next = best->bref.key; 1425 } else if (child->bref.key == best->bref.key) { 1426 /* 1427 * If our current best is flush with the child then this 1428 * is an illegal overlap. 1429 * 1430 * key_next will automatically be limited to the smaller of 1431 * the two end-points. 1432 */ 1433 KKASSERT(0); 1434 info->best = child; 1435 } else { 1436 /* 1437 * Keep the current best but truncate key_next to the child's 1438 * base. 1439 * 1440 * key_next will also automatically be limited to the smaller 1441 * of the two end-points (probably not necessary for this case 1442 * but we do it anyway). 1443 */ 1444 if (info->key_next > child->bref.key || info->key_next == 0) 1445 info->key_next = child->bref.key; 1446 } 1447 1448 /* 1449 * Always truncate key_next based on child's end-of-range. 1450 */ 1451 child_end = child->bref.key + ((hammer2_key_t)1 << child->bref.keybits); 1452 if (child_end && (info->key_next > child_end || info->key_next == 0)) 1453 info->key_next = child_end; 1454 1455 return(0); 1456 } 1457 1458 /* 1459 * Retrieve the specified chain from a media blockref, creating the 1460 * in-memory chain structure which reflects it. 1461 * 1462 * To handle insertion races pass the INSERT_RACE flag along with the 1463 * generation number of the core. NULL will be returned if the generation 1464 * number changes before we have a chance to insert the chain. Insert 1465 * races can occur because the parent might be held shared. 1466 * 1467 * Caller must hold the parent locked shared or exclusive since we may 1468 * need the parent's bref array to find our block. 1469 * 1470 * WARNING! chain->pmp is always set to NULL for any chain representing 1471 * part of the super-root topology. 1472 */ 1473 hammer2_chain_t * 1474 hammer2_chain_get(hammer2_chain_t *parent, int generation, 1475 hammer2_blockref_t *bref) 1476 { 1477 hammer2_dev_t *hmp = parent->hmp; 1478 hammer2_chain_t *chain; 1479 int error; 1480 1481 /* 1482 * Allocate a chain structure representing the existing media 1483 * entry. Resulting chain has one ref and is not locked. 1484 */ 1485 if (bref->flags & HAMMER2_BREF_FLAG_PFSROOT) 1486 chain = hammer2_chain_alloc(hmp, NULL, bref); 1487 else 1488 chain = hammer2_chain_alloc(hmp, parent->pmp, bref); 1489 /* ref'd chain returned */ 1490 1491 /* 1492 * Flag that the chain is in the parent's blockmap so delete/flush 1493 * knows what to do with it. 1494 */ 1495 atomic_set_int(&chain->flags, HAMMER2_CHAIN_BMAPPED); 1496 1497 /* 1498 * Link the chain into its parent. A spinlock is required to safely 1499 * access the RBTREE, and it is possible to collide with another 1500 * hammer2_chain_get() operation because the caller might only hold 1501 * a shared lock on the parent. 1502 */ 1503 KKASSERT(parent->refs > 0); 1504 error = hammer2_chain_insert(parent, chain, 1505 HAMMER2_CHAIN_INSERT_SPIN | 1506 HAMMER2_CHAIN_INSERT_RACE, 1507 generation); 1508 if (error) { 1509 KKASSERT((chain->flags & HAMMER2_CHAIN_ONRBTREE) == 0); 1510 kprintf("chain %p get race\n", chain); 1511 hammer2_chain_drop(chain); 1512 chain = NULL; 1513 } else { 1514 KKASSERT(chain->flags & HAMMER2_CHAIN_ONRBTREE); 1515 } 1516 1517 /* 1518 * Return our new chain referenced but not locked, or NULL if 1519 * a race occurred. 1520 */ 1521 return (chain); 1522 } 1523 1524 /* 1525 * Lookup initialization/completion API 1526 */ 1527 hammer2_chain_t * 1528 hammer2_chain_lookup_init(hammer2_chain_t *parent, int flags) 1529 { 1530 hammer2_chain_ref(parent); 1531 if (flags & HAMMER2_LOOKUP_SHARED) { 1532 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS | 1533 HAMMER2_RESOLVE_SHARED); 1534 } else { 1535 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS); 1536 } 1537 return (parent); 1538 } 1539 1540 void 1541 hammer2_chain_lookup_done(hammer2_chain_t *parent) 1542 { 1543 if (parent) { 1544 hammer2_chain_unlock(parent); 1545 hammer2_chain_drop(parent); 1546 } 1547 } 1548 1549 hammer2_chain_t * 1550 hammer2_chain_getparent(hammer2_chain_t **parentp, int how) 1551 { 1552 hammer2_chain_t *oparent; 1553 hammer2_chain_t *nparent; 1554 1555 /* 1556 * Be careful of order, oparent must be unlocked before nparent 1557 * is locked below to avoid a deadlock. 1558 */ 1559 oparent = *parentp; 1560 hammer2_spin_ex(&oparent->core.spin); 1561 nparent = oparent->parent; 1562 hammer2_chain_ref(nparent); 1563 hammer2_spin_unex(&oparent->core.spin); 1564 if (oparent) { 1565 hammer2_chain_unlock(oparent); 1566 hammer2_chain_drop(oparent); 1567 oparent = NULL; 1568 } 1569 1570 hammer2_chain_lock(nparent, how); 1571 *parentp = nparent; 1572 1573 return (nparent); 1574 } 1575 1576 /* 1577 * Locate the first chain whos key range overlaps (key_beg, key_end) inclusive. 1578 * (*parentp) typically points to an inode but can also point to a related 1579 * indirect block and this function will recurse upwards and find the inode 1580 * again. 1581 * 1582 * (*parentp) must be exclusively locked and referenced and can be an inode 1583 * or an existing indirect block within the inode. 1584 * 1585 * On return (*parentp) will be modified to point at the deepest parent chain 1586 * element encountered during the search, as a helper for an insertion or 1587 * deletion. The new (*parentp) will be locked and referenced and the old 1588 * will be unlocked and dereferenced (no change if they are both the same). 1589 * 1590 * The matching chain will be returned exclusively locked. If NOLOCK is 1591 * requested the chain will be returned only referenced. Note that the 1592 * parent chain must always be locked shared or exclusive, matching the 1593 * HAMMER2_LOOKUP_SHARED flag. We can conceivably lock it SHARED temporarily 1594 * when NOLOCK is specified but that complicates matters if *parentp must 1595 * inherit the chain. 1596 * 1597 * NOLOCK also implies NODATA, since an unlocked chain usually has a NULL 1598 * data pointer or can otherwise be in flux. 1599 * 1600 * NULL is returned if no match was found, but (*parentp) will still 1601 * potentially be adjusted. 1602 * 1603 * If a fatal error occurs (typically an I/O error), a dummy chain is 1604 * returned with chain->error and error-identifying information set. This 1605 * chain will assert if you try to do anything fancy with it. 1606 * 1607 * XXX Depending on where the error occurs we should allow continued iteration. 1608 * 1609 * On return (*key_nextp) will point to an iterative value for key_beg. 1610 * (If NULL is returned (*key_nextp) is set to (key_end + 1)). 1611 * 1612 * This function will also recurse up the chain if the key is not within the 1613 * current parent's range. (*parentp) can never be set to NULL. An iteration 1614 * can simply allow (*parentp) to float inside the loop. 1615 * 1616 * NOTE! chain->data is not always resolved. By default it will not be 1617 * resolved for BREF_TYPE_DATA, FREEMAP_NODE, or FREEMAP_LEAF. Use 1618 * HAMMER2_LOOKUP_ALWAYS to force resolution (but be careful w/ 1619 * BREF_TYPE_DATA as the device buffer can alias the logical file 1620 * buffer). 1621 */ 1622 hammer2_chain_t * 1623 hammer2_chain_lookup(hammer2_chain_t **parentp, hammer2_key_t *key_nextp, 1624 hammer2_key_t key_beg, hammer2_key_t key_end, 1625 int *cache_indexp, int flags) 1626 { 1627 hammer2_dev_t *hmp; 1628 hammer2_chain_t *parent; 1629 hammer2_chain_t *chain; 1630 hammer2_blockref_t *base; 1631 hammer2_blockref_t *bref; 1632 hammer2_blockref_t bcopy; 1633 hammer2_key_t scan_beg; 1634 hammer2_key_t scan_end; 1635 int count = 0; 1636 int how_always = HAMMER2_RESOLVE_ALWAYS; 1637 int how_maybe = HAMMER2_RESOLVE_MAYBE; 1638 int how; 1639 int generation; 1640 int maxloops = 300000; 1641 1642 if (flags & HAMMER2_LOOKUP_ALWAYS) { 1643 how_maybe = how_always; 1644 how = HAMMER2_RESOLVE_ALWAYS; 1645 } else if (flags & (HAMMER2_LOOKUP_NODATA | HAMMER2_LOOKUP_NOLOCK)) { 1646 how = HAMMER2_RESOLVE_NEVER; 1647 } else { 1648 how = HAMMER2_RESOLVE_MAYBE; 1649 } 1650 if (flags & HAMMER2_LOOKUP_SHARED) { 1651 how_maybe |= HAMMER2_RESOLVE_SHARED; 1652 how_always |= HAMMER2_RESOLVE_SHARED; 1653 how |= HAMMER2_RESOLVE_SHARED; 1654 } 1655 1656 /* 1657 * Recurse (*parentp) upward if necessary until the parent completely 1658 * encloses the key range or we hit the inode. 1659 * 1660 * This function handles races against the flusher doing a delete- 1661 * duplicate above us and re-homes the parent to the duplicate in 1662 * that case, otherwise we'd wind up recursing down a stale chain. 1663 */ 1664 parent = *parentp; 1665 hmp = parent->hmp; 1666 1667 while (parent->bref.type == HAMMER2_BREF_TYPE_INDIRECT || 1668 parent->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) { 1669 scan_beg = parent->bref.key; 1670 scan_end = scan_beg + 1671 ((hammer2_key_t)1 << parent->bref.keybits) - 1; 1672 if (key_beg >= scan_beg && key_end <= scan_end) 1673 break; 1674 parent = hammer2_chain_getparent(parentp, how_maybe); 1675 } 1676 1677 again: 1678 if (--maxloops == 0) 1679 panic("hammer2_chain_lookup: maxloops"); 1680 /* 1681 * Locate the blockref array. Currently we do a fully associative 1682 * search through the array. 1683 */ 1684 switch(parent->bref.type) { 1685 case HAMMER2_BREF_TYPE_INODE: 1686 /* 1687 * Special shortcut for embedded data returns the inode 1688 * itself. Callers must detect this condition and access 1689 * the embedded data (the strategy code does this for us). 1690 * 1691 * This is only applicable to regular files and softlinks. 1692 */ 1693 if (parent->data->ipdata.meta.op_flags & 1694 HAMMER2_OPFLAG_DIRECTDATA) { 1695 if (flags & HAMMER2_LOOKUP_NODIRECT) { 1696 chain = NULL; 1697 *key_nextp = key_end + 1; 1698 goto done; 1699 } 1700 hammer2_chain_ref(parent); 1701 if ((flags & HAMMER2_LOOKUP_NOLOCK) == 0) 1702 hammer2_chain_lock(parent, how_always); 1703 *key_nextp = key_end + 1; 1704 return (parent); 1705 } 1706 base = &parent->data->ipdata.u.blockset.blockref[0]; 1707 count = HAMMER2_SET_COUNT; 1708 break; 1709 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 1710 case HAMMER2_BREF_TYPE_INDIRECT: 1711 /* 1712 * Handle MATCHIND on the parent 1713 */ 1714 if (flags & HAMMER2_LOOKUP_MATCHIND) { 1715 scan_beg = parent->bref.key; 1716 scan_end = scan_beg + 1717 ((hammer2_key_t)1 << parent->bref.keybits) - 1; 1718 if (key_beg == scan_beg && key_end == scan_end) { 1719 chain = parent; 1720 hammer2_chain_ref(chain); 1721 hammer2_chain_lock(chain, how_maybe); 1722 *key_nextp = scan_end + 1; 1723 goto done; 1724 } 1725 } 1726 /* 1727 * Optimize indirect blocks in the INITIAL state to avoid 1728 * I/O. 1729 */ 1730 if (parent->flags & HAMMER2_CHAIN_INITIAL) { 1731 base = NULL; 1732 } else { 1733 if (parent->data == NULL) 1734 panic("parent->data is NULL"); 1735 base = &parent->data->npdata[0]; 1736 } 1737 count = parent->bytes / sizeof(hammer2_blockref_t); 1738 break; 1739 case HAMMER2_BREF_TYPE_VOLUME: 1740 base = &parent->data->voldata.sroot_blockset.blockref[0]; 1741 count = HAMMER2_SET_COUNT; 1742 break; 1743 case HAMMER2_BREF_TYPE_FREEMAP: 1744 base = &parent->data->blkset.blockref[0]; 1745 count = HAMMER2_SET_COUNT; 1746 break; 1747 default: 1748 kprintf("hammer2_chain_lookup: unrecognized " 1749 "blockref(B) type: %d", 1750 parent->bref.type); 1751 while (1) 1752 tsleep(&base, 0, "dead", 0); 1753 panic("hammer2_chain_lookup: unrecognized " 1754 "blockref(B) type: %d", 1755 parent->bref.type); 1756 base = NULL; /* safety */ 1757 count = 0; /* safety */ 1758 } 1759 1760 /* 1761 * Merged scan to find next candidate. 1762 * 1763 * hammer2_base_*() functions require the parent->core.live_* fields 1764 * to be synchronized. 1765 * 1766 * We need to hold the spinlock to access the block array and RB tree 1767 * and to interlock chain creation. 1768 */ 1769 if ((parent->flags & HAMMER2_CHAIN_COUNTEDBREFS) == 0) 1770 hammer2_chain_countbrefs(parent, base, count); 1771 1772 /* 1773 * Combined search 1774 */ 1775 hammer2_spin_ex(&parent->core.spin); 1776 chain = hammer2_combined_find(parent, base, count, 1777 cache_indexp, key_nextp, 1778 key_beg, key_end, 1779 &bref); 1780 generation = parent->core.generation; 1781 1782 /* 1783 * Exhausted parent chain, iterate. 1784 */ 1785 if (bref == NULL) { 1786 hammer2_spin_unex(&parent->core.spin); 1787 if (key_beg == key_end) /* short cut single-key case */ 1788 return (NULL); 1789 1790 /* 1791 * Stop if we reached the end of the iteration. 1792 */ 1793 if (parent->bref.type != HAMMER2_BREF_TYPE_INDIRECT && 1794 parent->bref.type != HAMMER2_BREF_TYPE_FREEMAP_NODE) { 1795 return (NULL); 1796 } 1797 1798 /* 1799 * Calculate next key, stop if we reached the end of the 1800 * iteration, otherwise go up one level and loop. 1801 */ 1802 key_beg = parent->bref.key + 1803 ((hammer2_key_t)1 << parent->bref.keybits); 1804 if (key_beg == 0 || key_beg > key_end) 1805 return (NULL); 1806 parent = hammer2_chain_getparent(parentp, how_maybe); 1807 goto again; 1808 } 1809 1810 /* 1811 * Selected from blockref or in-memory chain. 1812 */ 1813 if (chain == NULL) { 1814 bcopy = *bref; 1815 hammer2_spin_unex(&parent->core.spin); 1816 chain = hammer2_chain_get(parent, generation, 1817 &bcopy); 1818 if (chain == NULL) { 1819 kprintf("retry lookup parent %p keys %016jx:%016jx\n", 1820 parent, key_beg, key_end); 1821 goto again; 1822 } 1823 if (bcmp(&bcopy, bref, sizeof(bcopy))) { 1824 hammer2_chain_drop(chain); 1825 goto again; 1826 } 1827 } else { 1828 hammer2_chain_ref(chain); 1829 hammer2_spin_unex(&parent->core.spin); 1830 } 1831 1832 /* 1833 * chain is referenced but not locked. We must lock the chain 1834 * to obtain definitive DUPLICATED/DELETED state 1835 */ 1836 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT || 1837 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) { 1838 hammer2_chain_lock(chain, how_maybe); 1839 } else { 1840 hammer2_chain_lock(chain, how); 1841 } 1842 1843 /* 1844 * Skip deleted chains (XXX cache 'i' end-of-block-array? XXX) 1845 * 1846 * NOTE: Chain's key range is not relevant as there might be 1847 * one-offs within the range that are not deleted. 1848 * 1849 * NOTE: Lookups can race delete-duplicate because 1850 * delete-duplicate does not lock the parent's core 1851 * (they just use the spinlock on the core). We must 1852 * check for races by comparing the DUPLICATED flag before 1853 * releasing the spinlock with the flag after locking the 1854 * chain. 1855 */ 1856 if (chain->flags & HAMMER2_CHAIN_DELETED) { 1857 hammer2_chain_unlock(chain); 1858 hammer2_chain_drop(chain); 1859 key_beg = *key_nextp; 1860 if (key_beg == 0 || key_beg > key_end) 1861 return(NULL); 1862 goto again; 1863 } 1864 1865 /* 1866 * If the chain element is an indirect block it becomes the new 1867 * parent and we loop on it. We must maintain our top-down locks 1868 * to prevent the flusher from interfering (i.e. doing a 1869 * delete-duplicate and leaving us recursing down a deleted chain). 1870 * 1871 * The parent always has to be locked with at least RESOLVE_MAYBE 1872 * so we can access its data. It might need a fixup if the caller 1873 * passed incompatible flags. Be careful not to cause a deadlock 1874 * as a data-load requires an exclusive lock. 1875 * 1876 * If HAMMER2_LOOKUP_MATCHIND is set and the indirect block's key 1877 * range is within the requested key range we return the indirect 1878 * block and do NOT loop. This is usually only used to acquire 1879 * freemap nodes. 1880 */ 1881 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT || 1882 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) { 1883 hammer2_chain_unlock(parent); 1884 hammer2_chain_drop(parent); 1885 *parentp = parent = chain; 1886 goto again; 1887 } 1888 done: 1889 /* 1890 * All done, return the chain. 1891 * 1892 * If the caller does not want a locked chain, replace the lock with 1893 * a ref. Perhaps this can eventually be optimized to not obtain the 1894 * lock in the first place for situations where the data does not 1895 * need to be resolved. 1896 */ 1897 if (chain) { 1898 if (flags & HAMMER2_LOOKUP_NOLOCK) 1899 hammer2_chain_unlock(chain); 1900 } 1901 1902 return (chain); 1903 } 1904 1905 /* 1906 * After having issued a lookup we can iterate all matching keys. 1907 * 1908 * If chain is non-NULL we continue the iteration from just after it's index. 1909 * 1910 * If chain is NULL we assume the parent was exhausted and continue the 1911 * iteration at the next parent. 1912 * 1913 * If a fatal error occurs (typically an I/O error), a dummy chain is 1914 * returned with chain->error and error-identifying information set. This 1915 * chain will assert if you try to do anything fancy with it. 1916 * 1917 * XXX Depending on where the error occurs we should allow continued iteration. 1918 * 1919 * parent must be locked on entry and remains locked throughout. chain's 1920 * lock status must match flags. Chain is always at least referenced. 1921 * 1922 * WARNING! The MATCHIND flag does not apply to this function. 1923 */ 1924 hammer2_chain_t * 1925 hammer2_chain_next(hammer2_chain_t **parentp, hammer2_chain_t *chain, 1926 hammer2_key_t *key_nextp, 1927 hammer2_key_t key_beg, hammer2_key_t key_end, 1928 int *cache_indexp, int flags) 1929 { 1930 hammer2_chain_t *parent; 1931 int how_maybe; 1932 1933 /* 1934 * Calculate locking flags for upward recursion. 1935 */ 1936 how_maybe = HAMMER2_RESOLVE_MAYBE; 1937 if (flags & HAMMER2_LOOKUP_SHARED) 1938 how_maybe |= HAMMER2_RESOLVE_SHARED; 1939 1940 parent = *parentp; 1941 1942 /* 1943 * Calculate the next index and recalculate the parent if necessary. 1944 */ 1945 if (chain) { 1946 key_beg = chain->bref.key + 1947 ((hammer2_key_t)1 << chain->bref.keybits); 1948 if ((flags & (HAMMER2_LOOKUP_NOLOCK | 1949 HAMMER2_LOOKUP_NOUNLOCK)) == 0) { 1950 hammer2_chain_unlock(chain); 1951 } 1952 hammer2_chain_drop(chain); 1953 1954 /* 1955 * chain invalid past this point, but we can still do a 1956 * pointer comparison w/parent. 1957 * 1958 * Any scan where the lookup returned degenerate data embedded 1959 * in the inode has an invalid index and must terminate. 1960 */ 1961 if (chain == parent) 1962 return(NULL); 1963 if (key_beg == 0 || key_beg > key_end) 1964 return(NULL); 1965 chain = NULL; 1966 } else if (parent->bref.type != HAMMER2_BREF_TYPE_INDIRECT && 1967 parent->bref.type != HAMMER2_BREF_TYPE_FREEMAP_NODE) { 1968 /* 1969 * We reached the end of the iteration. 1970 */ 1971 return (NULL); 1972 } else { 1973 /* 1974 * Continue iteration with next parent unless the current 1975 * parent covers the range. 1976 */ 1977 key_beg = parent->bref.key + 1978 ((hammer2_key_t)1 << parent->bref.keybits); 1979 if (key_beg == 0 || key_beg > key_end) 1980 return (NULL); 1981 parent = hammer2_chain_getparent(parentp, how_maybe); 1982 } 1983 1984 /* 1985 * And execute 1986 */ 1987 return (hammer2_chain_lookup(parentp, key_nextp, 1988 key_beg, key_end, 1989 cache_indexp, flags)); 1990 } 1991 1992 /* 1993 * The raw scan function is similar to lookup/next but does not seek to a key. 1994 * Blockrefs are iterated via first_bref = (parent, NULL) and 1995 * next_chain = (parent, bref). 1996 * 1997 * The passed-in parent must be locked and its data resolved. The function 1998 * nominally returns a locked and referenced *chainp != NULL for chains 1999 * the caller might need to recurse on (and will dipose of any *chainp passed 2000 * in). The caller must check the chain->bref.type either way. 2001 * 2002 * *chainp is not set for leaf elements. 2003 * 2004 * This function takes a pointer to a stack-based bref structure whos 2005 * contents is updated for each iteration. The same pointer is returned, 2006 * or NULL when the iteration is complete. *firstp must be set to 1 for 2007 * the first ieration. This function will set it to 0. 2008 */ 2009 hammer2_blockref_t * 2010 hammer2_chain_scan(hammer2_chain_t *parent, hammer2_chain_t **chainp, 2011 hammer2_blockref_t *bref, int *firstp, 2012 int *cache_indexp, int flags) 2013 { 2014 hammer2_dev_t *hmp; 2015 hammer2_blockref_t *base; 2016 hammer2_blockref_t *bref_ptr; 2017 hammer2_key_t key; 2018 hammer2_key_t next_key; 2019 hammer2_chain_t *chain = NULL; 2020 int count = 0; 2021 int how_always = HAMMER2_RESOLVE_ALWAYS; 2022 int how_maybe = HAMMER2_RESOLVE_MAYBE; 2023 int how; 2024 int generation; 2025 int maxloops = 300000; 2026 2027 hmp = parent->hmp; 2028 2029 /* 2030 * Scan flags borrowed from lookup. 2031 */ 2032 if (flags & HAMMER2_LOOKUP_ALWAYS) { 2033 how_maybe = how_always; 2034 how = HAMMER2_RESOLVE_ALWAYS; 2035 } else if (flags & (HAMMER2_LOOKUP_NODATA | HAMMER2_LOOKUP_NOLOCK)) { 2036 how = HAMMER2_RESOLVE_NEVER; 2037 } else { 2038 how = HAMMER2_RESOLVE_MAYBE; 2039 } 2040 if (flags & HAMMER2_LOOKUP_SHARED) { 2041 how_maybe |= HAMMER2_RESOLVE_SHARED; 2042 how_always |= HAMMER2_RESOLVE_SHARED; 2043 how |= HAMMER2_RESOLVE_SHARED; 2044 } 2045 2046 /* 2047 * Calculate key to locate first/next element, unlocking the previous 2048 * element as we go. Be careful, the key calculation can overflow. 2049 * 2050 * (also reset bref to NULL) 2051 */ 2052 if (*firstp) { 2053 key = 0; 2054 *firstp = 0; 2055 } else { 2056 key = bref->key + ((hammer2_key_t)1 << bref->keybits); 2057 if ((chain = *chainp) != NULL) { 2058 *chainp = NULL; 2059 hammer2_chain_unlock(chain); 2060 hammer2_chain_drop(chain); 2061 chain = NULL; 2062 } 2063 if (key == 0) { 2064 bref = NULL; 2065 goto done; 2066 } 2067 } 2068 2069 again: 2070 KKASSERT(parent->error == 0); /* XXX case not handled yet */ 2071 if (--maxloops == 0) 2072 panic("hammer2_chain_scan: maxloops"); 2073 /* 2074 * Locate the blockref array. Currently we do a fully associative 2075 * search through the array. 2076 */ 2077 switch(parent->bref.type) { 2078 case HAMMER2_BREF_TYPE_INODE: 2079 /* 2080 * An inode with embedded data has no sub-chains. 2081 * 2082 * WARNING! Bulk scan code may pass a static chain marked 2083 * as BREF_TYPE_INODE with a copy of the volume 2084 * root blockset to snapshot the volume. 2085 */ 2086 if (parent->data->ipdata.meta.op_flags & 2087 HAMMER2_OPFLAG_DIRECTDATA) { 2088 bref = NULL; 2089 goto done; 2090 } 2091 base = &parent->data->ipdata.u.blockset.blockref[0]; 2092 count = HAMMER2_SET_COUNT; 2093 break; 2094 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 2095 case HAMMER2_BREF_TYPE_INDIRECT: 2096 /* 2097 * Optimize indirect blocks in the INITIAL state to avoid 2098 * I/O. 2099 */ 2100 if (parent->flags & HAMMER2_CHAIN_INITIAL) { 2101 base = NULL; 2102 } else { 2103 if (parent->data == NULL) 2104 panic("parent->data is NULL"); 2105 base = &parent->data->npdata[0]; 2106 } 2107 count = parent->bytes / sizeof(hammer2_blockref_t); 2108 break; 2109 case HAMMER2_BREF_TYPE_VOLUME: 2110 base = &parent->data->voldata.sroot_blockset.blockref[0]; 2111 count = HAMMER2_SET_COUNT; 2112 break; 2113 case HAMMER2_BREF_TYPE_FREEMAP: 2114 base = &parent->data->blkset.blockref[0]; 2115 count = HAMMER2_SET_COUNT; 2116 break; 2117 default: 2118 panic("hammer2_chain_lookup: unrecognized blockref type: %d", 2119 parent->bref.type); 2120 base = NULL; /* safety */ 2121 count = 0; /* safety */ 2122 } 2123 2124 /* 2125 * Merged scan to find next candidate. 2126 * 2127 * hammer2_base_*() functions require the parent->core.live_* fields 2128 * to be synchronized. 2129 * 2130 * We need to hold the spinlock to access the block array and RB tree 2131 * and to interlock chain creation. 2132 */ 2133 if ((parent->flags & HAMMER2_CHAIN_COUNTEDBREFS) == 0) 2134 hammer2_chain_countbrefs(parent, base, count); 2135 2136 next_key = 0; 2137 bref_ptr = NULL; 2138 hammer2_spin_ex(&parent->core.spin); 2139 chain = hammer2_combined_find(parent, base, count, 2140 cache_indexp, &next_key, 2141 key, HAMMER2_KEY_MAX, 2142 &bref_ptr); 2143 generation = parent->core.generation; 2144 2145 /* 2146 * Exhausted parent chain, we're done. 2147 */ 2148 if (bref_ptr == NULL) { 2149 hammer2_spin_unex(&parent->core.spin); 2150 KKASSERT(chain == NULL); 2151 bref = NULL; 2152 goto done; 2153 } 2154 2155 /* 2156 * Copy into the supplied stack-based blockref. 2157 */ 2158 *bref = *bref_ptr; 2159 2160 /* 2161 * Selected from blockref or in-memory chain. 2162 */ 2163 if (chain == NULL) { 2164 switch(bref->type) { 2165 case HAMMER2_BREF_TYPE_INODE: 2166 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 2167 case HAMMER2_BREF_TYPE_INDIRECT: 2168 case HAMMER2_BREF_TYPE_VOLUME: 2169 case HAMMER2_BREF_TYPE_FREEMAP: 2170 /* 2171 * Recursion, always get the chain 2172 */ 2173 hammer2_spin_unex(&parent->core.spin); 2174 chain = hammer2_chain_get(parent, generation, bref); 2175 if (chain == NULL) { 2176 kprintf("retry scan parent %p keys %016jx\n", 2177 parent, key); 2178 goto again; 2179 } 2180 if (bcmp(bref, bref_ptr, sizeof(*bref))) { 2181 hammer2_chain_drop(chain); 2182 chain = NULL; 2183 goto again; 2184 } 2185 break; 2186 default: 2187 /* 2188 * No recursion, do not waste time instantiating 2189 * a chain, just iterate using the bref. 2190 */ 2191 hammer2_spin_unex(&parent->core.spin); 2192 break; 2193 } 2194 } else { 2195 /* 2196 * Recursion or not we need the chain in order to supply 2197 * the bref. 2198 */ 2199 hammer2_chain_ref(chain); 2200 hammer2_spin_unex(&parent->core.spin); 2201 } 2202 2203 /* 2204 * chain is referenced but not locked. We must lock the chain 2205 * to obtain definitive DUPLICATED/DELETED state 2206 */ 2207 if (chain) 2208 hammer2_chain_lock(chain, how); 2209 2210 /* 2211 * Skip deleted chains (XXX cache 'i' end-of-block-array? XXX) 2212 * 2213 * NOTE: chain's key range is not relevant as there might be 2214 * one-offs within the range that are not deleted. 2215 * 2216 * NOTE: XXX this could create problems with scans used in 2217 * situations other than mount-time recovery. 2218 * 2219 * NOTE: Lookups can race delete-duplicate because 2220 * delete-duplicate does not lock the parent's core 2221 * (they just use the spinlock on the core). We must 2222 * check for races by comparing the DUPLICATED flag before 2223 * releasing the spinlock with the flag after locking the 2224 * chain. 2225 */ 2226 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) { 2227 hammer2_chain_unlock(chain); 2228 hammer2_chain_drop(chain); 2229 chain = NULL; 2230 2231 key = next_key; 2232 if (key == 0) { 2233 bref = NULL; 2234 goto done; 2235 } 2236 goto again; 2237 } 2238 2239 done: 2240 /* 2241 * All done, return the bref or NULL, supply chain if necessary. 2242 */ 2243 if (chain) 2244 *chainp = chain; 2245 return (bref); 2246 } 2247 2248 /* 2249 * Create and return a new hammer2 system memory structure of the specified 2250 * key, type and size and insert it under (*parentp). This is a full 2251 * insertion, based on the supplied key/keybits, and may involve creating 2252 * indirect blocks and moving other chains around via delete/duplicate. 2253 * 2254 * THE CALLER MUST HAVE ALREADY PROPERLY SEEKED (*parentp) TO THE INSERTION 2255 * POINT SANS ANY REQUIRED INDIRECT BLOCK CREATIONS DUE TO THE ARRAY BEING 2256 * FULL. This typically means that the caller is creating the chain after 2257 * doing a hammer2_chain_lookup(). 2258 * 2259 * (*parentp) must be exclusive locked and may be replaced on return 2260 * depending on how much work the function had to do. 2261 * 2262 * (*parentp) must not be errored or this function will assert. 2263 * 2264 * (*chainp) usually starts out NULL and returns the newly created chain, 2265 * but if the caller desires the caller may allocate a disconnected chain 2266 * and pass it in instead. 2267 * 2268 * This function should NOT be used to insert INDIRECT blocks. It is 2269 * typically used to create/insert inodes and data blocks. 2270 * 2271 * Caller must pass-in an exclusively locked parent the new chain is to 2272 * be inserted under, and optionally pass-in a disconnected, exclusively 2273 * locked chain to insert (else we create a new chain). The function will 2274 * adjust (*parentp) as necessary, create or connect the chain, and 2275 * return an exclusively locked chain in *chainp. 2276 * 2277 * When creating a PFSROOT inode under the super-root, pmp is typically NULL 2278 * and will be reassigned. 2279 */ 2280 int 2281 hammer2_chain_create(hammer2_chain_t **parentp, 2282 hammer2_chain_t **chainp, hammer2_pfs_t *pmp, 2283 hammer2_key_t key, int keybits, int type, size_t bytes, 2284 hammer2_tid_t mtid, hammer2_off_t dedup_off, int flags) 2285 { 2286 hammer2_dev_t *hmp; 2287 hammer2_chain_t *chain; 2288 hammer2_chain_t *parent; 2289 hammer2_blockref_t *base; 2290 hammer2_blockref_t dummy; 2291 int allocated = 0; 2292 int error = 0; 2293 int count; 2294 int maxloops = 300000; 2295 2296 /* 2297 * Topology may be crossing a PFS boundary. 2298 */ 2299 parent = *parentp; 2300 KKASSERT(hammer2_mtx_owned(&parent->lock)); 2301 KKASSERT(parent->error == 0); 2302 hmp = parent->hmp; 2303 chain = *chainp; 2304 2305 if (chain == NULL) { 2306 /* 2307 * First allocate media space and construct the dummy bref, 2308 * then allocate the in-memory chain structure. Set the 2309 * INITIAL flag for fresh chains which do not have embedded 2310 * data. 2311 * 2312 * XXX for now set the check mode of the child based on 2313 * the parent or, if the parent is an inode, the 2314 * specification in the inode. 2315 */ 2316 bzero(&dummy, sizeof(dummy)); 2317 dummy.type = type; 2318 dummy.key = key; 2319 dummy.keybits = keybits; 2320 dummy.data_off = hammer2_getradix(bytes); 2321 dummy.methods = parent->bref.methods; 2322 if (parent->bref.type == HAMMER2_BREF_TYPE_INODE && 2323 parent->data) { 2324 dummy.methods &= ~HAMMER2_ENC_CHECK(-1); 2325 dummy.methods |= HAMMER2_ENC_CHECK( 2326 parent->data->ipdata.meta.check_algo); 2327 } 2328 2329 chain = hammer2_chain_alloc(hmp, pmp, &dummy); 2330 2331 /* 2332 * Lock the chain manually, chain_lock will load the chain 2333 * which we do NOT want to do. (note: chain->refs is set 2334 * to 1 by chain_alloc() for us, but lockcnt is not). 2335 */ 2336 chain->lockcnt = 1; 2337 hammer2_mtx_ex(&chain->lock); 2338 allocated = 1; 2339 2340 /* 2341 * Set INITIAL to optimize I/O. The flag will generally be 2342 * processed when we call hammer2_chain_modify(). 2343 * 2344 * Recalculate bytes to reflect the actual media block 2345 * allocation. 2346 */ 2347 bytes = (hammer2_off_t)1 << 2348 (int)(chain->bref.data_off & HAMMER2_OFF_MASK_RADIX); 2349 chain->bytes = bytes; 2350 2351 switch(type) { 2352 case HAMMER2_BREF_TYPE_VOLUME: 2353 case HAMMER2_BREF_TYPE_FREEMAP: 2354 panic("hammer2_chain_create: called with volume type"); 2355 break; 2356 case HAMMER2_BREF_TYPE_INDIRECT: 2357 panic("hammer2_chain_create: cannot be used to" 2358 "create indirect block"); 2359 break; 2360 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 2361 panic("hammer2_chain_create: cannot be used to" 2362 "create freemap root or node"); 2363 break; 2364 case HAMMER2_BREF_TYPE_FREEMAP_LEAF: 2365 KKASSERT(bytes == sizeof(chain->data->bmdata)); 2366 /* fall through */ 2367 case HAMMER2_BREF_TYPE_INODE: 2368 case HAMMER2_BREF_TYPE_DATA: 2369 default: 2370 /* 2371 * leave chain->data NULL, set INITIAL 2372 */ 2373 KKASSERT(chain->data == NULL); 2374 atomic_set_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 2375 break; 2376 } 2377 } else { 2378 /* 2379 * We are reattaching a previously deleted chain, possibly 2380 * under a new parent and possibly with a new key/keybits. 2381 * The chain does not have to be in a modified state. The 2382 * UPDATE flag will be set later on in this routine. 2383 * 2384 * Do NOT mess with the current state of the INITIAL flag. 2385 */ 2386 chain->bref.key = key; 2387 chain->bref.keybits = keybits; 2388 if (chain->flags & HAMMER2_CHAIN_DELETED) 2389 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_DELETED); 2390 KKASSERT(chain->parent == NULL); 2391 } 2392 if (flags & HAMMER2_INSERT_PFSROOT) 2393 chain->bref.flags |= HAMMER2_BREF_FLAG_PFSROOT; 2394 else 2395 chain->bref.flags &= ~HAMMER2_BREF_FLAG_PFSROOT; 2396 2397 /* 2398 * Calculate how many entries we have in the blockref array and 2399 * determine if an indirect block is required. 2400 */ 2401 again: 2402 if (--maxloops == 0) 2403 panic("hammer2_chain_create: maxloops"); 2404 2405 switch(parent->bref.type) { 2406 case HAMMER2_BREF_TYPE_INODE: 2407 KKASSERT((parent->data->ipdata.meta.op_flags & 2408 HAMMER2_OPFLAG_DIRECTDATA) == 0); 2409 KKASSERT(parent->data != NULL); 2410 base = &parent->data->ipdata.u.blockset.blockref[0]; 2411 count = HAMMER2_SET_COUNT; 2412 break; 2413 case HAMMER2_BREF_TYPE_INDIRECT: 2414 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 2415 if (parent->flags & HAMMER2_CHAIN_INITIAL) 2416 base = NULL; 2417 else 2418 base = &parent->data->npdata[0]; 2419 count = parent->bytes / sizeof(hammer2_blockref_t); 2420 break; 2421 case HAMMER2_BREF_TYPE_VOLUME: 2422 KKASSERT(parent->data != NULL); 2423 base = &parent->data->voldata.sroot_blockset.blockref[0]; 2424 count = HAMMER2_SET_COUNT; 2425 break; 2426 case HAMMER2_BREF_TYPE_FREEMAP: 2427 KKASSERT(parent->data != NULL); 2428 base = &parent->data->blkset.blockref[0]; 2429 count = HAMMER2_SET_COUNT; 2430 break; 2431 default: 2432 panic("hammer2_chain_create: unrecognized blockref type: %d", 2433 parent->bref.type); 2434 base = NULL; 2435 count = 0; 2436 break; 2437 } 2438 2439 /* 2440 * Make sure we've counted the brefs 2441 */ 2442 if ((parent->flags & HAMMER2_CHAIN_COUNTEDBREFS) == 0) 2443 hammer2_chain_countbrefs(parent, base, count); 2444 2445 KKASSERT(parent->core.live_count >= 0 && 2446 parent->core.live_count <= count); 2447 2448 /* 2449 * If no free blockref could be found we must create an indirect 2450 * block and move a number of blockrefs into it. With the parent 2451 * locked we can safely lock each child in order to delete+duplicate 2452 * it without causing a deadlock. 2453 * 2454 * This may return the new indirect block or the old parent depending 2455 * on where the key falls. NULL is returned on error. 2456 */ 2457 if (parent->core.live_count == count) { 2458 hammer2_chain_t *nparent; 2459 2460 nparent = hammer2_chain_create_indirect(parent, key, keybits, 2461 mtid, type, &error); 2462 if (nparent == NULL) { 2463 if (allocated) 2464 hammer2_chain_drop(chain); 2465 chain = NULL; 2466 goto done; 2467 } 2468 if (parent != nparent) { 2469 hammer2_chain_unlock(parent); 2470 hammer2_chain_drop(parent); 2471 parent = *parentp = nparent; 2472 } 2473 goto again; 2474 } 2475 2476 /* 2477 * Link the chain into its parent. 2478 */ 2479 if (chain->parent != NULL) 2480 panic("hammer2: hammer2_chain_create: chain already connected"); 2481 KKASSERT(chain->parent == NULL); 2482 hammer2_chain_insert(parent, chain, 2483 HAMMER2_CHAIN_INSERT_SPIN | 2484 HAMMER2_CHAIN_INSERT_LIVE, 2485 0); 2486 2487 if (allocated) { 2488 /* 2489 * Mark the newly created chain modified. This will cause 2490 * UPDATE to be set and process the INITIAL flag. 2491 * 2492 * Device buffers are not instantiated for DATA elements 2493 * as these are handled by logical buffers. 2494 * 2495 * Indirect and freemap node indirect blocks are handled 2496 * by hammer2_chain_create_indirect() and not by this 2497 * function. 2498 * 2499 * Data for all other bref types is expected to be 2500 * instantiated (INODE, LEAF). 2501 */ 2502 switch(chain->bref.type) { 2503 case HAMMER2_BREF_TYPE_DATA: 2504 case HAMMER2_BREF_TYPE_FREEMAP_LEAF: 2505 case HAMMER2_BREF_TYPE_INODE: 2506 hammer2_chain_modify(chain, mtid, dedup_off, 2507 HAMMER2_MODIFY_OPTDATA); 2508 break; 2509 default: 2510 /* 2511 * Remaining types are not supported by this function. 2512 * In particular, INDIRECT and LEAF_NODE types are 2513 * handled by create_indirect(). 2514 */ 2515 panic("hammer2_chain_create: bad type: %d", 2516 chain->bref.type); 2517 /* NOT REACHED */ 2518 break; 2519 } 2520 } else { 2521 /* 2522 * When reconnecting a chain we must set UPDATE and 2523 * setflush so the flush recognizes that it must update 2524 * the bref in the parent. 2525 */ 2526 if ((chain->flags & HAMMER2_CHAIN_UPDATE) == 0) { 2527 hammer2_chain_ref(chain); 2528 atomic_set_int(&chain->flags, HAMMER2_CHAIN_UPDATE); 2529 } 2530 } 2531 2532 /* 2533 * We must setflush(parent) to ensure that it recurses through to 2534 * chain. setflush(chain) might not work because ONFLUSH is possibly 2535 * already set in the chain (so it won't recurse up to set it in the 2536 * parent). 2537 */ 2538 hammer2_chain_setflush(parent); 2539 2540 done: 2541 *chainp = chain; 2542 2543 return (error); 2544 } 2545 2546 /* 2547 * Move the chain from its old parent to a new parent. The chain must have 2548 * already been deleted or already disconnected (or never associated) with 2549 * a parent. The chain is reassociated with the new parent and the deleted 2550 * flag will be cleared (no longer deleted). The chain's modification state 2551 * is not altered. 2552 * 2553 * THE CALLER MUST HAVE ALREADY PROPERLY SEEKED (parent) TO THE INSERTION 2554 * POINT SANS ANY REQUIRED INDIRECT BLOCK CREATIONS DUE TO THE ARRAY BEING 2555 * FULL. This typically means that the caller is creating the chain after 2556 * doing a hammer2_chain_lookup(). 2557 * 2558 * A non-NULL bref is typically passed when key and keybits must be overridden. 2559 * Note that hammer2_cluster_duplicate() *ONLY* uses the key and keybits fields 2560 * from a passed-in bref and uses the old chain's bref for everything else. 2561 * 2562 * Neither (parent) or (chain) can be errored. 2563 * 2564 * If (parent) is non-NULL then the new duplicated chain is inserted under 2565 * the parent. 2566 * 2567 * If (parent) is NULL then the newly duplicated chain is not inserted 2568 * anywhere, similar to if it had just been chain_alloc()'d (suitable for 2569 * passing into hammer2_chain_create() after this function returns). 2570 * 2571 * WARNING! This function calls create which means it can insert indirect 2572 * blocks. This can cause other unrelated chains in the parent to 2573 * be moved to a newly inserted indirect block in addition to the 2574 * specific chain. 2575 */ 2576 void 2577 hammer2_chain_rename(hammer2_blockref_t *bref, 2578 hammer2_chain_t **parentp, hammer2_chain_t *chain, 2579 hammer2_tid_t mtid, int flags) 2580 { 2581 hammer2_dev_t *hmp; 2582 hammer2_chain_t *parent; 2583 size_t bytes; 2584 2585 /* 2586 * WARNING! We should never resolve DATA to device buffers 2587 * (XXX allow it if the caller did?), and since 2588 * we currently do not have the logical buffer cache 2589 * buffer in-hand to fix its cached physical offset 2590 * we also force the modify code to not COW it. XXX 2591 */ 2592 hmp = chain->hmp; 2593 KKASSERT(chain->parent == NULL); 2594 KKASSERT(chain->error == 0); 2595 2596 /* 2597 * Now create a duplicate of the chain structure, associating 2598 * it with the same core, making it the same size, pointing it 2599 * to the same bref (the same media block). 2600 */ 2601 if (bref == NULL) 2602 bref = &chain->bref; 2603 bytes = (hammer2_off_t)1 << 2604 (int)(bref->data_off & HAMMER2_OFF_MASK_RADIX); 2605 2606 /* 2607 * If parent is not NULL the duplicated chain will be entered under 2608 * the parent and the UPDATE bit set to tell flush to update 2609 * the blockref. 2610 * 2611 * We must setflush(parent) to ensure that it recurses through to 2612 * chain. setflush(chain) might not work because ONFLUSH is possibly 2613 * already set in the chain (so it won't recurse up to set it in the 2614 * parent). 2615 * 2616 * Having both chains locked is extremely important for atomicy. 2617 */ 2618 if (parentp && (parent = *parentp) != NULL) { 2619 KKASSERT(hammer2_mtx_owned(&parent->lock)); 2620 KKASSERT(parent->refs > 0); 2621 KKASSERT(parent->error == 0); 2622 2623 hammer2_chain_create(parentp, &chain, chain->pmp, 2624 bref->key, bref->keybits, bref->type, 2625 chain->bytes, mtid, 0, flags); 2626 KKASSERT(chain->flags & HAMMER2_CHAIN_UPDATE); 2627 hammer2_chain_setflush(*parentp); 2628 } 2629 } 2630 2631 /* 2632 * Helper function for deleting chains. 2633 * 2634 * The chain is removed from the live view (the RBTREE) as well as the parent's 2635 * blockmap. Both chain and its parent must be locked. 2636 * 2637 * parent may not be errored. chain can be errored. 2638 */ 2639 static void 2640 _hammer2_chain_delete_helper(hammer2_chain_t *parent, hammer2_chain_t *chain, 2641 hammer2_tid_t mtid, int flags) 2642 { 2643 hammer2_dev_t *hmp; 2644 2645 KKASSERT((chain->flags & (HAMMER2_CHAIN_DELETED | 2646 HAMMER2_CHAIN_FICTITIOUS)) == 0); 2647 KKASSERT(chain->parent == parent); 2648 hmp = chain->hmp; 2649 2650 if (chain->flags & HAMMER2_CHAIN_BMAPPED) { 2651 /* 2652 * Chain is blockmapped, so there must be a parent. 2653 * Atomically remove the chain from the parent and remove 2654 * the blockmap entry. 2655 */ 2656 hammer2_blockref_t *base; 2657 int count; 2658 2659 KKASSERT(parent != NULL); 2660 KKASSERT(parent->error == 0); 2661 KKASSERT((parent->flags & HAMMER2_CHAIN_INITIAL) == 0); 2662 hammer2_chain_modify(parent, mtid, 0, HAMMER2_MODIFY_OPTDATA); 2663 2664 /* 2665 * Calculate blockmap pointer 2666 */ 2667 KKASSERT(chain->flags & HAMMER2_CHAIN_ONRBTREE); 2668 hammer2_spin_ex(&parent->core.spin); 2669 2670 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DELETED); 2671 atomic_add_int(&parent->core.live_count, -1); 2672 ++parent->core.generation; 2673 RB_REMOVE(hammer2_chain_tree, &parent->core.rbtree, chain); 2674 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE); 2675 --parent->core.chain_count; 2676 chain->parent = NULL; 2677 2678 switch(parent->bref.type) { 2679 case HAMMER2_BREF_TYPE_INODE: 2680 /* 2681 * Access the inode's block array. However, there 2682 * is no block array if the inode is flagged 2683 * DIRECTDATA. The DIRECTDATA case typicaly only 2684 * occurs when a hardlink has been shifted up the 2685 * tree and the original inode gets replaced with 2686 * an OBJTYPE_HARDLINK placeholding inode. 2687 */ 2688 if (parent->data && 2689 (parent->data->ipdata.meta.op_flags & 2690 HAMMER2_OPFLAG_DIRECTDATA) == 0) { 2691 base = 2692 &parent->data->ipdata.u.blockset.blockref[0]; 2693 } else { 2694 base = NULL; 2695 } 2696 count = HAMMER2_SET_COUNT; 2697 break; 2698 case HAMMER2_BREF_TYPE_INDIRECT: 2699 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 2700 if (parent->data) 2701 base = &parent->data->npdata[0]; 2702 else 2703 base = NULL; 2704 count = parent->bytes / sizeof(hammer2_blockref_t); 2705 break; 2706 case HAMMER2_BREF_TYPE_VOLUME: 2707 base = &parent->data->voldata. 2708 sroot_blockset.blockref[0]; 2709 count = HAMMER2_SET_COUNT; 2710 break; 2711 case HAMMER2_BREF_TYPE_FREEMAP: 2712 base = &parent->data->blkset.blockref[0]; 2713 count = HAMMER2_SET_COUNT; 2714 break; 2715 default: 2716 base = NULL; 2717 count = 0; 2718 panic("hammer2_flush_pass2: " 2719 "unrecognized blockref type: %d", 2720 parent->bref.type); 2721 } 2722 2723 /* 2724 * delete blockmapped chain from its parent. 2725 * 2726 * The parent is not affected by any statistics in chain 2727 * which are pending synchronization. That is, there is 2728 * nothing to undo in the parent since they have not yet 2729 * been incorporated into the parent. 2730 * 2731 * The parent is affected by statistics stored in inodes. 2732 * Those have already been synchronized, so they must be 2733 * undone. XXX split update possible w/delete in middle? 2734 */ 2735 if (base) { 2736 int cache_index = -1; 2737 hammer2_base_delete(parent, base, count, 2738 &cache_index, chain); 2739 } 2740 hammer2_spin_unex(&parent->core.spin); 2741 } else if (chain->flags & HAMMER2_CHAIN_ONRBTREE) { 2742 /* 2743 * Chain is not blockmapped but a parent is present. 2744 * Atomically remove the chain from the parent. There is 2745 * no blockmap entry to remove. 2746 * 2747 * Because chain was associated with a parent but not 2748 * synchronized, the chain's *_count_up fields contain 2749 * inode adjustment statistics which must be undone. 2750 */ 2751 hammer2_spin_ex(&parent->core.spin); 2752 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DELETED); 2753 atomic_add_int(&parent->core.live_count, -1); 2754 ++parent->core.generation; 2755 RB_REMOVE(hammer2_chain_tree, &parent->core.rbtree, chain); 2756 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE); 2757 --parent->core.chain_count; 2758 chain->parent = NULL; 2759 hammer2_spin_unex(&parent->core.spin); 2760 } else { 2761 /* 2762 * Chain is not blockmapped and has no parent. This 2763 * is a degenerate case. 2764 */ 2765 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DELETED); 2766 } 2767 } 2768 2769 /* 2770 * Create an indirect block that covers one or more of the elements in the 2771 * current parent. Either returns the existing parent with no locking or 2772 * ref changes or returns the new indirect block locked and referenced 2773 * and leaving the original parent lock/ref intact as well. 2774 * 2775 * If an error occurs, NULL is returned and *errorp is set to the error. 2776 * 2777 * The returned chain depends on where the specified key falls. 2778 * 2779 * The key/keybits for the indirect mode only needs to follow three rules: 2780 * 2781 * (1) That all elements underneath it fit within its key space and 2782 * 2783 * (2) That all elements outside it are outside its key space. 2784 * 2785 * (3) When creating the new indirect block any elements in the current 2786 * parent that fit within the new indirect block's keyspace must be 2787 * moved into the new indirect block. 2788 * 2789 * (4) The keyspace chosen for the inserted indirect block CAN cover a wider 2790 * keyspace the the current parent, but lookup/iteration rules will 2791 * ensure (and must ensure) that rule (2) for all parents leading up 2792 * to the nearest inode or the root volume header is adhered to. This 2793 * is accomplished by always recursing through matching keyspaces in 2794 * the hammer2_chain_lookup() and hammer2_chain_next() API. 2795 * 2796 * The current implementation calculates the current worst-case keyspace by 2797 * iterating the current parent and then divides it into two halves, choosing 2798 * whichever half has the most elements (not necessarily the half containing 2799 * the requested key). 2800 * 2801 * We can also opt to use the half with the least number of elements. This 2802 * causes lower-numbered keys (aka logical file offsets) to recurse through 2803 * fewer indirect blocks and higher-numbered keys to recurse through more. 2804 * This also has the risk of not moving enough elements to the new indirect 2805 * block and being forced to create several indirect blocks before the element 2806 * can be inserted. 2807 * 2808 * Must be called with an exclusively locked parent. 2809 */ 2810 static int hammer2_chain_indkey_freemap(hammer2_chain_t *parent, 2811 hammer2_key_t *keyp, int keybits, 2812 hammer2_blockref_t *base, int count); 2813 static int hammer2_chain_indkey_normal(hammer2_chain_t *parent, 2814 hammer2_key_t *keyp, int keybits, 2815 hammer2_blockref_t *base, int count); 2816 static 2817 hammer2_chain_t * 2818 hammer2_chain_create_indirect(hammer2_chain_t *parent, 2819 hammer2_key_t create_key, int create_bits, 2820 hammer2_tid_t mtid, int for_type, int *errorp) 2821 { 2822 hammer2_dev_t *hmp; 2823 hammer2_blockref_t *base; 2824 hammer2_blockref_t *bref; 2825 hammer2_blockref_t bcopy; 2826 hammer2_chain_t *chain; 2827 hammer2_chain_t *ichain; 2828 hammer2_chain_t dummy; 2829 hammer2_key_t key = create_key; 2830 hammer2_key_t key_beg; 2831 hammer2_key_t key_end; 2832 hammer2_key_t key_next; 2833 int keybits = create_bits; 2834 int count; 2835 int nbytes; 2836 int cache_index; 2837 int loops; 2838 int reason; 2839 int generation; 2840 int maxloops = 300000; 2841 2842 /* 2843 * Calculate the base blockref pointer or NULL if the chain 2844 * is known to be empty. We need to calculate the array count 2845 * for RB lookups either way. 2846 */ 2847 hmp = parent->hmp; 2848 *errorp = 0; 2849 KKASSERT(hammer2_mtx_owned(&parent->lock)); 2850 2851 /*hammer2_chain_modify(&parent, HAMMER2_MODIFY_OPTDATA);*/ 2852 if (parent->flags & HAMMER2_CHAIN_INITIAL) { 2853 base = NULL; 2854 2855 switch(parent->bref.type) { 2856 case HAMMER2_BREF_TYPE_INODE: 2857 count = HAMMER2_SET_COUNT; 2858 break; 2859 case HAMMER2_BREF_TYPE_INDIRECT: 2860 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 2861 count = parent->bytes / sizeof(hammer2_blockref_t); 2862 break; 2863 case HAMMER2_BREF_TYPE_VOLUME: 2864 count = HAMMER2_SET_COUNT; 2865 break; 2866 case HAMMER2_BREF_TYPE_FREEMAP: 2867 count = HAMMER2_SET_COUNT; 2868 break; 2869 default: 2870 panic("hammer2_chain_create_indirect: " 2871 "unrecognized blockref type: %d", 2872 parent->bref.type); 2873 count = 0; 2874 break; 2875 } 2876 } else { 2877 switch(parent->bref.type) { 2878 case HAMMER2_BREF_TYPE_INODE: 2879 base = &parent->data->ipdata.u.blockset.blockref[0]; 2880 count = HAMMER2_SET_COUNT; 2881 break; 2882 case HAMMER2_BREF_TYPE_INDIRECT: 2883 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 2884 base = &parent->data->npdata[0]; 2885 count = parent->bytes / sizeof(hammer2_blockref_t); 2886 break; 2887 case HAMMER2_BREF_TYPE_VOLUME: 2888 base = &parent->data->voldata. 2889 sroot_blockset.blockref[0]; 2890 count = HAMMER2_SET_COUNT; 2891 break; 2892 case HAMMER2_BREF_TYPE_FREEMAP: 2893 base = &parent->data->blkset.blockref[0]; 2894 count = HAMMER2_SET_COUNT; 2895 break; 2896 default: 2897 panic("hammer2_chain_create_indirect: " 2898 "unrecognized blockref type: %d", 2899 parent->bref.type); 2900 count = 0; 2901 break; 2902 } 2903 } 2904 2905 /* 2906 * dummy used in later chain allocation (no longer used for lookups). 2907 */ 2908 bzero(&dummy, sizeof(dummy)); 2909 2910 /* 2911 * When creating an indirect block for a freemap node or leaf 2912 * the key/keybits must be fitted to static radix levels because 2913 * particular radix levels use particular reserved blocks in the 2914 * related zone. 2915 * 2916 * This routine calculates the key/radix of the indirect block 2917 * we need to create, and whether it is on the high-side or the 2918 * low-side. 2919 */ 2920 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE || 2921 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) { 2922 keybits = hammer2_chain_indkey_freemap(parent, &key, keybits, 2923 base, count); 2924 } else { 2925 keybits = hammer2_chain_indkey_normal(parent, &key, keybits, 2926 base, count); 2927 } 2928 2929 /* 2930 * Normalize the key for the radix being represented, keeping the 2931 * high bits and throwing away the low bits. 2932 */ 2933 key &= ~(((hammer2_key_t)1 << keybits) - 1); 2934 2935 /* 2936 * How big should our new indirect block be? It has to be at least 2937 * as large as its parent. 2938 * 2939 * The freemap uses a specific indirect block size. 2940 * 2941 * The first indirect block level down from an inode typically 2942 * uses LBUFSIZE (16384), else it uses PBUFSIZE (65536). 2943 */ 2944 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE || 2945 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) { 2946 nbytes = HAMMER2_FREEMAP_LEVELN_PSIZE; 2947 } else if (parent->bref.type == HAMMER2_BREF_TYPE_INODE) { 2948 nbytes = HAMMER2_IND_BYTES_MIN; 2949 } else { 2950 nbytes = HAMMER2_IND_BYTES_MAX; 2951 } 2952 if (nbytes < count * sizeof(hammer2_blockref_t)) { 2953 KKASSERT(for_type != HAMMER2_BREF_TYPE_FREEMAP_NODE && 2954 for_type != HAMMER2_BREF_TYPE_FREEMAP_LEAF); 2955 nbytes = count * sizeof(hammer2_blockref_t); 2956 } 2957 2958 /* 2959 * Ok, create our new indirect block 2960 */ 2961 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE || 2962 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) { 2963 dummy.bref.type = HAMMER2_BREF_TYPE_FREEMAP_NODE; 2964 } else { 2965 dummy.bref.type = HAMMER2_BREF_TYPE_INDIRECT; 2966 } 2967 dummy.bref.key = key; 2968 dummy.bref.keybits = keybits; 2969 dummy.bref.data_off = hammer2_getradix(nbytes); 2970 dummy.bref.methods = parent->bref.methods; 2971 2972 ichain = hammer2_chain_alloc(hmp, parent->pmp, &dummy.bref); 2973 atomic_set_int(&ichain->flags, HAMMER2_CHAIN_INITIAL); 2974 hammer2_chain_lock(ichain, HAMMER2_RESOLVE_MAYBE); 2975 /* ichain has one ref at this point */ 2976 2977 /* 2978 * We have to mark it modified to allocate its block, but use 2979 * OPTDATA to allow it to remain in the INITIAL state. Otherwise 2980 * it won't be acted upon by the flush code. 2981 */ 2982 hammer2_chain_modify(ichain, mtid, 0, HAMMER2_MODIFY_OPTDATA); 2983 2984 /* 2985 * Iterate the original parent and move the matching brefs into 2986 * the new indirect block. 2987 * 2988 * XXX handle flushes. 2989 */ 2990 key_beg = 0; 2991 key_end = HAMMER2_KEY_MAX; 2992 cache_index = 0; 2993 hammer2_spin_ex(&parent->core.spin); 2994 loops = 0; 2995 reason = 0; 2996 2997 for (;;) { 2998 if (++loops > 100000) { 2999 hammer2_spin_unex(&parent->core.spin); 3000 panic("excessive loops r=%d p=%p base/count %p:%d %016jx\n", 3001 reason, parent, base, count, key_next); 3002 } 3003 3004 /* 3005 * NOTE: spinlock stays intact, returned chain (if not NULL) 3006 * is not referenced or locked which means that we 3007 * cannot safely check its flagged / deletion status 3008 * until we lock it. 3009 */ 3010 chain = hammer2_combined_find(parent, base, count, 3011 &cache_index, &key_next, 3012 key_beg, key_end, 3013 &bref); 3014 generation = parent->core.generation; 3015 if (bref == NULL) 3016 break; 3017 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits); 3018 3019 /* 3020 * Skip keys that are not within the key/radix of the new 3021 * indirect block. They stay in the parent. 3022 */ 3023 if ((~(((hammer2_key_t)1 << keybits) - 1) & 3024 (key ^ bref->key)) != 0) { 3025 goto next_key_spinlocked; 3026 } 3027 3028 /* 3029 * Load the new indirect block by acquiring the related 3030 * chains (potentially from media as it might not be 3031 * in-memory). Then move it to the new parent (ichain) 3032 * via DELETE-DUPLICATE. 3033 * 3034 * chain is referenced but not locked. We must lock the 3035 * chain to obtain definitive DUPLICATED/DELETED state 3036 */ 3037 if (chain) { 3038 /* 3039 * Use chain already present in the RBTREE 3040 */ 3041 hammer2_chain_ref(chain); 3042 hammer2_spin_unex(&parent->core.spin); 3043 hammer2_chain_lock(chain, HAMMER2_RESOLVE_NEVER); 3044 } else { 3045 /* 3046 * Get chain for blockref element. _get returns NULL 3047 * on insertion race. 3048 */ 3049 bcopy = *bref; 3050 hammer2_spin_unex(&parent->core.spin); 3051 chain = hammer2_chain_get(parent, generation, &bcopy); 3052 if (chain == NULL) { 3053 reason = 1; 3054 hammer2_spin_ex(&parent->core.spin); 3055 continue; 3056 } 3057 if (bcmp(&bcopy, bref, sizeof(bcopy))) { 3058 kprintf("REASON 2\n"); 3059 reason = 2; 3060 hammer2_chain_drop(chain); 3061 hammer2_spin_ex(&parent->core.spin); 3062 continue; 3063 } 3064 hammer2_chain_lock(chain, HAMMER2_RESOLVE_NEVER); 3065 } 3066 3067 /* 3068 * This is always live so if the chain has been deleted 3069 * we raced someone and we have to retry. 3070 * 3071 * NOTE: Lookups can race delete-duplicate because 3072 * delete-duplicate does not lock the parent's core 3073 * (they just use the spinlock on the core). We must 3074 * check for races by comparing the DUPLICATED flag before 3075 * releasing the spinlock with the flag after locking the 3076 * chain. 3077 * 3078 * (note reversed logic for this one) 3079 */ 3080 if (chain->flags & HAMMER2_CHAIN_DELETED) { 3081 hammer2_chain_unlock(chain); 3082 hammer2_chain_drop(chain); 3083 goto next_key; 3084 } 3085 3086 /* 3087 * Shift the chain to the indirect block. 3088 * 3089 * WARNING! No reason for us to load chain data, pass NOSTATS 3090 * to prevent delete/insert from trying to access 3091 * inode stats (and thus asserting if there is no 3092 * chain->data loaded). 3093 */ 3094 hammer2_chain_delete(parent, chain, mtid, 0); 3095 hammer2_chain_rename(NULL, &ichain, chain, mtid, 0); 3096 hammer2_chain_unlock(chain); 3097 hammer2_chain_drop(chain); 3098 KKASSERT(parent->refs > 0); 3099 chain = NULL; 3100 next_key: 3101 hammer2_spin_ex(&parent->core.spin); 3102 next_key_spinlocked: 3103 if (--maxloops == 0) 3104 panic("hammer2_chain_create_indirect: maxloops"); 3105 reason = 4; 3106 if (key_next == 0 || key_next > key_end) 3107 break; 3108 key_beg = key_next; 3109 /* loop */ 3110 } 3111 hammer2_spin_unex(&parent->core.spin); 3112 3113 /* 3114 * Insert the new indirect block into the parent now that we've 3115 * cleared out some entries in the parent. We calculated a good 3116 * insertion index in the loop above (ichain->index). 3117 * 3118 * We don't have to set UPDATE here because we mark ichain 3119 * modified down below (so the normal modified -> flush -> set-moved 3120 * sequence applies). 3121 * 3122 * The insertion shouldn't race as this is a completely new block 3123 * and the parent is locked. 3124 */ 3125 KKASSERT((ichain->flags & HAMMER2_CHAIN_ONRBTREE) == 0); 3126 hammer2_chain_insert(parent, ichain, 3127 HAMMER2_CHAIN_INSERT_SPIN | 3128 HAMMER2_CHAIN_INSERT_LIVE, 3129 0); 3130 3131 /* 3132 * Make sure flushes propogate after our manual insertion. 3133 */ 3134 hammer2_chain_setflush(ichain); 3135 hammer2_chain_setflush(parent); 3136 3137 /* 3138 * Figure out what to return. 3139 */ 3140 if (~(((hammer2_key_t)1 << keybits) - 1) & 3141 (create_key ^ key)) { 3142 /* 3143 * Key being created is outside the key range, 3144 * return the original parent. 3145 */ 3146 hammer2_chain_unlock(ichain); 3147 hammer2_chain_drop(ichain); 3148 } else { 3149 /* 3150 * Otherwise its in the range, return the new parent. 3151 * (leave both the new and old parent locked). 3152 */ 3153 parent = ichain; 3154 } 3155 3156 return(parent); 3157 } 3158 3159 /* 3160 * Calculate the keybits and highside/lowside of the freemap node the 3161 * caller is creating. 3162 * 3163 * This routine will specify the next higher-level freemap key/radix 3164 * representing the lowest-ordered set. By doing so, eventually all 3165 * low-ordered sets will be moved one level down. 3166 * 3167 * We have to be careful here because the freemap reserves a limited 3168 * number of blocks for a limited number of levels. So we can't just 3169 * push indiscriminately. 3170 */ 3171 int 3172 hammer2_chain_indkey_freemap(hammer2_chain_t *parent, hammer2_key_t *keyp, 3173 int keybits, hammer2_blockref_t *base, int count) 3174 { 3175 hammer2_chain_t *chain; 3176 hammer2_blockref_t *bref; 3177 hammer2_key_t key; 3178 hammer2_key_t key_beg; 3179 hammer2_key_t key_end; 3180 hammer2_key_t key_next; 3181 int cache_index; 3182 int locount; 3183 int hicount; 3184 int maxloops = 300000; 3185 3186 key = *keyp; 3187 locount = 0; 3188 hicount = 0; 3189 keybits = 64; 3190 3191 /* 3192 * Calculate the range of keys in the array being careful to skip 3193 * slots which are overridden with a deletion. 3194 */ 3195 key_beg = 0; 3196 key_end = HAMMER2_KEY_MAX; 3197 cache_index = 0; 3198 hammer2_spin_ex(&parent->core.spin); 3199 3200 for (;;) { 3201 if (--maxloops == 0) { 3202 panic("indkey_freemap shit %p %p:%d\n", 3203 parent, base, count); 3204 } 3205 chain = hammer2_combined_find(parent, base, count, 3206 &cache_index, &key_next, 3207 key_beg, key_end, 3208 &bref); 3209 3210 /* 3211 * Exhausted search 3212 */ 3213 if (bref == NULL) 3214 break; 3215 3216 /* 3217 * Skip deleted chains. 3218 */ 3219 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) { 3220 if (key_next == 0 || key_next > key_end) 3221 break; 3222 key_beg = key_next; 3223 continue; 3224 } 3225 3226 /* 3227 * Use the full live (not deleted) element for the scan 3228 * iteration. HAMMER2 does not allow partial replacements. 3229 * 3230 * XXX should be built into hammer2_combined_find(). 3231 */ 3232 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits); 3233 3234 if (keybits > bref->keybits) { 3235 key = bref->key; 3236 keybits = bref->keybits; 3237 } else if (keybits == bref->keybits && bref->key < key) { 3238 key = bref->key; 3239 } 3240 if (key_next == 0) 3241 break; 3242 key_beg = key_next; 3243 } 3244 hammer2_spin_unex(&parent->core.spin); 3245 3246 /* 3247 * Return the keybits for a higher-level FREEMAP_NODE covering 3248 * this node. 3249 */ 3250 switch(keybits) { 3251 case HAMMER2_FREEMAP_LEVEL0_RADIX: 3252 keybits = HAMMER2_FREEMAP_LEVEL1_RADIX; 3253 break; 3254 case HAMMER2_FREEMAP_LEVEL1_RADIX: 3255 keybits = HAMMER2_FREEMAP_LEVEL2_RADIX; 3256 break; 3257 case HAMMER2_FREEMAP_LEVEL2_RADIX: 3258 keybits = HAMMER2_FREEMAP_LEVEL3_RADIX; 3259 break; 3260 case HAMMER2_FREEMAP_LEVEL3_RADIX: 3261 keybits = HAMMER2_FREEMAP_LEVEL4_RADIX; 3262 break; 3263 case HAMMER2_FREEMAP_LEVEL4_RADIX: 3264 keybits = HAMMER2_FREEMAP_LEVEL5_RADIX; 3265 break; 3266 case HAMMER2_FREEMAP_LEVEL5_RADIX: 3267 panic("hammer2_chain_indkey_freemap: level too high"); 3268 break; 3269 default: 3270 panic("hammer2_chain_indkey_freemap: bad radix"); 3271 break; 3272 } 3273 *keyp = key; 3274 3275 return (keybits); 3276 } 3277 3278 /* 3279 * Calculate the keybits and highside/lowside of the indirect block the 3280 * caller is creating. 3281 */ 3282 static int 3283 hammer2_chain_indkey_normal(hammer2_chain_t *parent, hammer2_key_t *keyp, 3284 int keybits, hammer2_blockref_t *base, int count) 3285 { 3286 hammer2_blockref_t *bref; 3287 hammer2_chain_t *chain; 3288 hammer2_key_t key_beg; 3289 hammer2_key_t key_end; 3290 hammer2_key_t key_next; 3291 hammer2_key_t key; 3292 int nkeybits; 3293 int locount; 3294 int hicount; 3295 int cache_index; 3296 int maxloops = 300000; 3297 3298 key = *keyp; 3299 locount = 0; 3300 hicount = 0; 3301 3302 /* 3303 * Calculate the range of keys in the array being careful to skip 3304 * slots which are overridden with a deletion. Once the scan 3305 * completes we will cut the key range in half and shift half the 3306 * range into the new indirect block. 3307 */ 3308 key_beg = 0; 3309 key_end = HAMMER2_KEY_MAX; 3310 cache_index = 0; 3311 hammer2_spin_ex(&parent->core.spin); 3312 3313 for (;;) { 3314 if (--maxloops == 0) { 3315 panic("indkey_freemap shit %p %p:%d\n", 3316 parent, base, count); 3317 } 3318 chain = hammer2_combined_find(parent, base, count, 3319 &cache_index, &key_next, 3320 key_beg, key_end, 3321 &bref); 3322 3323 /* 3324 * Exhausted search 3325 */ 3326 if (bref == NULL) 3327 break; 3328 3329 /* 3330 * NOTE: No need to check DUPLICATED here because we do 3331 * not release the spinlock. 3332 */ 3333 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) { 3334 if (key_next == 0 || key_next > key_end) 3335 break; 3336 key_beg = key_next; 3337 continue; 3338 } 3339 3340 /* 3341 * Use the full live (not deleted) element for the scan 3342 * iteration. HAMMER2 does not allow partial replacements. 3343 * 3344 * XXX should be built into hammer2_combined_find(). 3345 */ 3346 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits); 3347 3348 /* 3349 * Expand our calculated key range (key, keybits) to fit 3350 * the scanned key. nkeybits represents the full range 3351 * that we will later cut in half (two halves @ nkeybits - 1). 3352 */ 3353 nkeybits = keybits; 3354 if (nkeybits < bref->keybits) { 3355 if (bref->keybits > 64) { 3356 kprintf("bad bref chain %p bref %p\n", 3357 chain, bref); 3358 Debugger("fubar"); 3359 } 3360 nkeybits = bref->keybits; 3361 } 3362 while (nkeybits < 64 && 3363 (~(((hammer2_key_t)1 << nkeybits) - 1) & 3364 (key ^ bref->key)) != 0) { 3365 ++nkeybits; 3366 } 3367 3368 /* 3369 * If the new key range is larger we have to determine 3370 * which side of the new key range the existing keys fall 3371 * under by checking the high bit, then collapsing the 3372 * locount into the hicount or vise-versa. 3373 */ 3374 if (keybits != nkeybits) { 3375 if (((hammer2_key_t)1 << (nkeybits - 1)) & key) { 3376 hicount += locount; 3377 locount = 0; 3378 } else { 3379 locount += hicount; 3380 hicount = 0; 3381 } 3382 keybits = nkeybits; 3383 } 3384 3385 /* 3386 * The newly scanned key will be in the lower half or the 3387 * upper half of the (new) key range. 3388 */ 3389 if (((hammer2_key_t)1 << (nkeybits - 1)) & bref->key) 3390 ++hicount; 3391 else 3392 ++locount; 3393 3394 if (key_next == 0) 3395 break; 3396 key_beg = key_next; 3397 } 3398 hammer2_spin_unex(&parent->core.spin); 3399 bref = NULL; /* now invalid (safety) */ 3400 3401 /* 3402 * Adjust keybits to represent half of the full range calculated 3403 * above (radix 63 max) 3404 */ 3405 --keybits; 3406 3407 /* 3408 * Select whichever half contains the most elements. Theoretically 3409 * we can select either side as long as it contains at least one 3410 * element (in order to ensure that a free slot is present to hold 3411 * the indirect block). 3412 */ 3413 if (hammer2_indirect_optimize) { 3414 /* 3415 * Insert node for least number of keys, this will arrange 3416 * the first few blocks of a large file or the first few 3417 * inodes in a directory with fewer indirect blocks when 3418 * created linearly. 3419 */ 3420 if (hicount < locount && hicount != 0) 3421 key |= (hammer2_key_t)1 << keybits; 3422 else 3423 key &= ~(hammer2_key_t)1 << keybits; 3424 } else { 3425 /* 3426 * Insert node for most number of keys, best for heavily 3427 * fragmented files. 3428 */ 3429 if (hicount > locount) 3430 key |= (hammer2_key_t)1 << keybits; 3431 else 3432 key &= ~(hammer2_key_t)1 << keybits; 3433 } 3434 *keyp = key; 3435 3436 return (keybits); 3437 } 3438 3439 /* 3440 * Sets CHAIN_DELETED and remove the chain's blockref from the parent if 3441 * it exists. 3442 * 3443 * Both parent and chain must be locked exclusively. 3444 * 3445 * This function will modify the parent if the blockref requires removal 3446 * from the parent's block table. 3447 * 3448 * This function is NOT recursive. Any entity already pushed into the 3449 * chain (such as an inode) may still need visibility into its contents, 3450 * as well as the ability to read and modify the contents. For example, 3451 * for an unlinked file which is still open. 3452 */ 3453 void 3454 hammer2_chain_delete(hammer2_chain_t *parent, hammer2_chain_t *chain, 3455 hammer2_tid_t mtid, int flags) 3456 { 3457 KKASSERT(hammer2_mtx_owned(&chain->lock)); 3458 3459 /* 3460 * Nothing to do if already marked. 3461 * 3462 * We need the spinlock on the core whos RBTREE contains chain 3463 * to protect against races. 3464 */ 3465 if ((chain->flags & HAMMER2_CHAIN_DELETED) == 0) { 3466 KKASSERT((chain->flags & HAMMER2_CHAIN_DELETED) == 0 && 3467 chain->parent == parent); 3468 _hammer2_chain_delete_helper(parent, chain, mtid, flags); 3469 } 3470 3471 /* 3472 * To avoid losing track of a permanent deletion we add the chain 3473 * to the delayed flush queue. If were to flush it right now the 3474 * parent would end up in a modified state and generate I/O. 3475 * The delayed queue gives the parent a chance to be deleted to 3476 * (e.g. rm -rf). 3477 */ 3478 if (flags & HAMMER2_DELETE_PERMANENT) { 3479 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DESTROY); 3480 hammer2_delayed_flush(chain); 3481 } else { 3482 /* XXX might not be needed */ 3483 hammer2_chain_setflush(chain); 3484 } 3485 } 3486 3487 /* 3488 * Returns the index of the nearest element in the blockref array >= elm. 3489 * Returns (count) if no element could be found. 3490 * 3491 * Sets *key_nextp to the next key for loop purposes but does not modify 3492 * it if the next key would be higher than the current value of *key_nextp. 3493 * Note that *key_nexp can overflow to 0, which should be tested by the 3494 * caller. 3495 * 3496 * (*cache_indexp) is a heuristic and can be any value without effecting 3497 * the result. 3498 * 3499 * WARNING! Must be called with parent's spinlock held. Spinlock remains 3500 * held through the operation. 3501 */ 3502 static int 3503 hammer2_base_find(hammer2_chain_t *parent, 3504 hammer2_blockref_t *base, int count, 3505 int *cache_indexp, hammer2_key_t *key_nextp, 3506 hammer2_key_t key_beg, hammer2_key_t key_end) 3507 { 3508 hammer2_blockref_t *scan; 3509 hammer2_key_t scan_end; 3510 int i; 3511 int limit; 3512 3513 /* 3514 * Require the live chain's already have their core's counted 3515 * so we can optimize operations. 3516 */ 3517 KKASSERT(parent->flags & HAMMER2_CHAIN_COUNTEDBREFS); 3518 3519 /* 3520 * Degenerate case 3521 */ 3522 if (count == 0 || base == NULL) 3523 return(count); 3524 3525 /* 3526 * Sequential optimization using *cache_indexp. This is the most 3527 * likely scenario. 3528 * 3529 * We can avoid trailing empty entries on live chains, otherwise 3530 * we might have to check the whole block array. 3531 */ 3532 i = *cache_indexp; 3533 cpu_ccfence(); 3534 limit = parent->core.live_zero; 3535 if (i >= limit) 3536 i = limit - 1; 3537 if (i < 0) 3538 i = 0; 3539 KKASSERT(i < count); 3540 3541 /* 3542 * Search backwards 3543 */ 3544 scan = &base[i]; 3545 while (i > 0 && (scan->type == 0 || scan->key > key_beg)) { 3546 --scan; 3547 --i; 3548 } 3549 *cache_indexp = i; 3550 3551 /* 3552 * Search forwards, stop when we find a scan element which 3553 * encloses the key or until we know that there are no further 3554 * elements. 3555 */ 3556 while (i < count) { 3557 if (scan->type != 0) { 3558 scan_end = scan->key + 3559 ((hammer2_key_t)1 << scan->keybits) - 1; 3560 if (scan->key > key_beg || scan_end >= key_beg) 3561 break; 3562 } 3563 if (i >= limit) 3564 return (count); 3565 ++scan; 3566 ++i; 3567 } 3568 if (i != count) { 3569 *cache_indexp = i; 3570 if (i >= limit) { 3571 i = count; 3572 } else { 3573 scan_end = scan->key + 3574 ((hammer2_key_t)1 << scan->keybits); 3575 if (scan_end && (*key_nextp > scan_end || 3576 *key_nextp == 0)) { 3577 *key_nextp = scan_end; 3578 } 3579 } 3580 } 3581 return (i); 3582 } 3583 3584 /* 3585 * Do a combined search and return the next match either from the blockref 3586 * array or from the in-memory chain. Sets *bresp to the returned bref in 3587 * both cases, or sets it to NULL if the search exhausted. Only returns 3588 * a non-NULL chain if the search matched from the in-memory chain. 3589 * 3590 * When no in-memory chain has been found and a non-NULL bref is returned 3591 * in *bresp. 3592 * 3593 * 3594 * The returned chain is not locked or referenced. Use the returned bref 3595 * to determine if the search exhausted or not. Iterate if the base find 3596 * is chosen but matches a deleted chain. 3597 * 3598 * WARNING! Must be called with parent's spinlock held. Spinlock remains 3599 * held through the operation. 3600 */ 3601 static hammer2_chain_t * 3602 hammer2_combined_find(hammer2_chain_t *parent, 3603 hammer2_blockref_t *base, int count, 3604 int *cache_indexp, hammer2_key_t *key_nextp, 3605 hammer2_key_t key_beg, hammer2_key_t key_end, 3606 hammer2_blockref_t **bresp) 3607 { 3608 hammer2_blockref_t *bref; 3609 hammer2_chain_t *chain; 3610 int i; 3611 3612 /* 3613 * Lookup in block array and in rbtree. 3614 */ 3615 *key_nextp = key_end + 1; 3616 i = hammer2_base_find(parent, base, count, cache_indexp, 3617 key_nextp, key_beg, key_end); 3618 chain = hammer2_chain_find(parent, key_nextp, key_beg, key_end); 3619 3620 /* 3621 * Neither matched 3622 */ 3623 if (i == count && chain == NULL) { 3624 *bresp = NULL; 3625 return(NULL); 3626 } 3627 3628 /* 3629 * Only chain matched. 3630 */ 3631 if (i == count) { 3632 bref = &chain->bref; 3633 goto found; 3634 } 3635 3636 /* 3637 * Only blockref matched. 3638 */ 3639 if (chain == NULL) { 3640 bref = &base[i]; 3641 goto found; 3642 } 3643 3644 /* 3645 * Both in-memory and blockref matched, select the nearer element. 3646 * 3647 * If both are flush with the left-hand side or both are the 3648 * same distance away, select the chain. In this situation the 3649 * chain must have been loaded from the matching blockmap. 3650 */ 3651 if ((chain->bref.key <= key_beg && base[i].key <= key_beg) || 3652 chain->bref.key == base[i].key) { 3653 KKASSERT(chain->bref.key == base[i].key); 3654 bref = &chain->bref; 3655 goto found; 3656 } 3657 3658 /* 3659 * Select the nearer key 3660 */ 3661 if (chain->bref.key < base[i].key) { 3662 bref = &chain->bref; 3663 } else { 3664 bref = &base[i]; 3665 chain = NULL; 3666 } 3667 3668 /* 3669 * If the bref is out of bounds we've exhausted our search. 3670 */ 3671 found: 3672 if (bref->key > key_end) { 3673 *bresp = NULL; 3674 chain = NULL; 3675 } else { 3676 *bresp = bref; 3677 } 3678 return(chain); 3679 } 3680 3681 /* 3682 * Locate the specified block array element and delete it. The element 3683 * must exist. 3684 * 3685 * The spin lock on the related chain must be held. 3686 * 3687 * NOTE: live_count was adjusted when the chain was deleted, so it does not 3688 * need to be adjusted when we commit the media change. 3689 */ 3690 void 3691 hammer2_base_delete(hammer2_chain_t *parent, 3692 hammer2_blockref_t *base, int count, 3693 int *cache_indexp, hammer2_chain_t *chain) 3694 { 3695 hammer2_blockref_t *elm = &chain->bref; 3696 hammer2_key_t key_next; 3697 int i; 3698 3699 /* 3700 * Delete element. Expect the element to exist. 3701 * 3702 * XXX see caller, flush code not yet sophisticated enough to prevent 3703 * re-flushed in some cases. 3704 */ 3705 key_next = 0; /* max range */ 3706 i = hammer2_base_find(parent, base, count, cache_indexp, 3707 &key_next, elm->key, elm->key); 3708 if (i == count || base[i].type == 0 || 3709 base[i].key != elm->key || 3710 ((chain->flags & HAMMER2_CHAIN_BMAPUPD) == 0 && 3711 base[i].keybits != elm->keybits)) { 3712 hammer2_spin_unex(&parent->core.spin); 3713 panic("delete base %p element not found at %d/%d elm %p\n", 3714 base, i, count, elm); 3715 return; 3716 } 3717 3718 /* 3719 * Update stats and zero the entry 3720 */ 3721 parent->bref.data_count -= base[i].data_count; 3722 parent->bref.data_count -= (hammer2_off_t)1 << 3723 (int)(base[i].data_off & HAMMER2_OFF_MASK_RADIX); 3724 parent->bref.inode_count -= base[i].inode_count; 3725 if (base[i].type == HAMMER2_BREF_TYPE_INODE) 3726 parent->bref.inode_count -= 1; 3727 3728 bzero(&base[i], sizeof(*base)); 3729 3730 /* 3731 * We can only optimize parent->core.live_zero for live chains. 3732 */ 3733 if (parent->core.live_zero == i + 1) { 3734 while (--i >= 0 && base[i].type == 0) 3735 ; 3736 parent->core.live_zero = i + 1; 3737 } 3738 3739 /* 3740 * Clear appropriate blockmap flags in chain. 3741 */ 3742 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_BMAPPED | 3743 HAMMER2_CHAIN_BMAPUPD); 3744 } 3745 3746 /* 3747 * Insert the specified element. The block array must not already have the 3748 * element and must have space available for the insertion. 3749 * 3750 * The spin lock on the related chain must be held. 3751 * 3752 * NOTE: live_count was adjusted when the chain was deleted, so it does not 3753 * need to be adjusted when we commit the media change. 3754 */ 3755 void 3756 hammer2_base_insert(hammer2_chain_t *parent, 3757 hammer2_blockref_t *base, int count, 3758 int *cache_indexp, hammer2_chain_t *chain) 3759 { 3760 hammer2_blockref_t *elm = &chain->bref; 3761 hammer2_key_t key_next; 3762 hammer2_key_t xkey; 3763 int i; 3764 int j; 3765 int k; 3766 int l; 3767 int u = 1; 3768 3769 /* 3770 * Insert new element. Expect the element to not already exist 3771 * unless we are replacing it. 3772 * 3773 * XXX see caller, flush code not yet sophisticated enough to prevent 3774 * re-flushed in some cases. 3775 */ 3776 key_next = 0; /* max range */ 3777 i = hammer2_base_find(parent, base, count, cache_indexp, 3778 &key_next, elm->key, elm->key); 3779 3780 /* 3781 * Shortcut fill optimization, typical ordered insertion(s) may not 3782 * require a search. 3783 */ 3784 KKASSERT(i >= 0 && i <= count); 3785 3786 /* 3787 * Set appropriate blockmap flags in chain. 3788 */ 3789 atomic_set_int(&chain->flags, HAMMER2_CHAIN_BMAPPED); 3790 3791 /* 3792 * Update stats and zero the entry 3793 */ 3794 parent->bref.data_count += elm->data_count; 3795 parent->bref.data_count += (hammer2_off_t)1 << 3796 (int)(elm->data_off & HAMMER2_OFF_MASK_RADIX); 3797 parent->bref.inode_count += elm->inode_count; 3798 if (elm->type == HAMMER2_BREF_TYPE_INODE) 3799 parent->bref.inode_count += 1; 3800 3801 3802 /* 3803 * We can only optimize parent->core.live_zero for live chains. 3804 */ 3805 if (i == count && parent->core.live_zero < count) { 3806 i = parent->core.live_zero++; 3807 base[i] = *elm; 3808 return; 3809 } 3810 3811 xkey = elm->key + ((hammer2_key_t)1 << elm->keybits) - 1; 3812 if (i != count && (base[i].key < elm->key || xkey >= base[i].key)) { 3813 hammer2_spin_unex(&parent->core.spin); 3814 panic("insert base %p overlapping elements at %d elm %p\n", 3815 base, i, elm); 3816 } 3817 3818 /* 3819 * Try to find an empty slot before or after. 3820 */ 3821 j = i; 3822 k = i; 3823 while (j > 0 || k < count) { 3824 --j; 3825 if (j >= 0 && base[j].type == 0) { 3826 if (j == i - 1) { 3827 base[j] = *elm; 3828 } else { 3829 bcopy(&base[j+1], &base[j], 3830 (i - j - 1) * sizeof(*base)); 3831 base[i - 1] = *elm; 3832 } 3833 goto validate; 3834 } 3835 ++k; 3836 if (k < count && base[k].type == 0) { 3837 bcopy(&base[i], &base[i+1], 3838 (k - i) * sizeof(hammer2_blockref_t)); 3839 base[i] = *elm; 3840 3841 /* 3842 * We can only update parent->core.live_zero for live 3843 * chains. 3844 */ 3845 if (parent->core.live_zero <= k) 3846 parent->core.live_zero = k + 1; 3847 u = 2; 3848 goto validate; 3849 } 3850 } 3851 panic("hammer2_base_insert: no room!"); 3852 3853 /* 3854 * Debugging 3855 */ 3856 validate: 3857 key_next = 0; 3858 for (l = 0; l < count; ++l) { 3859 if (base[l].type) { 3860 key_next = base[l].key + 3861 ((hammer2_key_t)1 << base[l].keybits) - 1; 3862 break; 3863 } 3864 } 3865 while (++l < count) { 3866 if (base[l].type) { 3867 if (base[l].key <= key_next) 3868 panic("base_insert %d %d,%d,%d fail %p:%d", u, i, j, k, base, l); 3869 key_next = base[l].key + 3870 ((hammer2_key_t)1 << base[l].keybits) - 1; 3871 3872 } 3873 } 3874 3875 } 3876 3877 #if 0 3878 3879 /* 3880 * Sort the blockref array for the chain. Used by the flush code to 3881 * sort the blockref[] array. 3882 * 3883 * The chain must be exclusively locked AND spin-locked. 3884 */ 3885 typedef hammer2_blockref_t *hammer2_blockref_p; 3886 3887 static 3888 int 3889 hammer2_base_sort_callback(const void *v1, const void *v2) 3890 { 3891 hammer2_blockref_p bref1 = *(const hammer2_blockref_p *)v1; 3892 hammer2_blockref_p bref2 = *(const hammer2_blockref_p *)v2; 3893 3894 /* 3895 * Make sure empty elements are placed at the end of the array 3896 */ 3897 if (bref1->type == 0) { 3898 if (bref2->type == 0) 3899 return(0); 3900 return(1); 3901 } else if (bref2->type == 0) { 3902 return(-1); 3903 } 3904 3905 /* 3906 * Sort by key 3907 */ 3908 if (bref1->key < bref2->key) 3909 return(-1); 3910 if (bref1->key > bref2->key) 3911 return(1); 3912 return(0); 3913 } 3914 3915 void 3916 hammer2_base_sort(hammer2_chain_t *chain) 3917 { 3918 hammer2_blockref_t *base; 3919 int count; 3920 3921 switch(chain->bref.type) { 3922 case HAMMER2_BREF_TYPE_INODE: 3923 /* 3924 * Special shortcut for embedded data returns the inode 3925 * itself. Callers must detect this condition and access 3926 * the embedded data (the strategy code does this for us). 3927 * 3928 * This is only applicable to regular files and softlinks. 3929 */ 3930 if (chain->data->ipdata.meta.op_flags & 3931 HAMMER2_OPFLAG_DIRECTDATA) { 3932 return; 3933 } 3934 base = &chain->data->ipdata.u.blockset.blockref[0]; 3935 count = HAMMER2_SET_COUNT; 3936 break; 3937 case HAMMER2_BREF_TYPE_FREEMAP_NODE: 3938 case HAMMER2_BREF_TYPE_INDIRECT: 3939 /* 3940 * Optimize indirect blocks in the INITIAL state to avoid 3941 * I/O. 3942 */ 3943 KKASSERT((chain->flags & HAMMER2_CHAIN_INITIAL) == 0); 3944 base = &chain->data->npdata[0]; 3945 count = chain->bytes / sizeof(hammer2_blockref_t); 3946 break; 3947 case HAMMER2_BREF_TYPE_VOLUME: 3948 base = &chain->data->voldata.sroot_blockset.blockref[0]; 3949 count = HAMMER2_SET_COUNT; 3950 break; 3951 case HAMMER2_BREF_TYPE_FREEMAP: 3952 base = &chain->data->blkset.blockref[0]; 3953 count = HAMMER2_SET_COUNT; 3954 break; 3955 default: 3956 kprintf("hammer2_chain_lookup: unrecognized " 3957 "blockref(A) type: %d", 3958 chain->bref.type); 3959 while (1) 3960 tsleep(&base, 0, "dead", 0); 3961 panic("hammer2_chain_lookup: unrecognized " 3962 "blockref(A) type: %d", 3963 chain->bref.type); 3964 base = NULL; /* safety */ 3965 count = 0; /* safety */ 3966 } 3967 kqsort(base, count, sizeof(*base), hammer2_base_sort_callback); 3968 } 3969 3970 #endif 3971 3972 /* 3973 * Chain memory management 3974 */ 3975 void 3976 hammer2_chain_wait(hammer2_chain_t *chain) 3977 { 3978 tsleep(chain, 0, "chnflw", 1); 3979 } 3980 3981 const hammer2_media_data_t * 3982 hammer2_chain_rdata(hammer2_chain_t *chain) 3983 { 3984 KKASSERT(chain->data != NULL); 3985 return (chain->data); 3986 } 3987 3988 hammer2_media_data_t * 3989 hammer2_chain_wdata(hammer2_chain_t *chain) 3990 { 3991 KKASSERT(chain->data != NULL); 3992 return (chain->data); 3993 } 3994 3995 /* 3996 * Set the check data for a chain. This can be a heavy-weight operation 3997 * and typically only runs on-flush. For file data check data is calculated 3998 * when the logical buffers are flushed. 3999 */ 4000 void 4001 hammer2_chain_setcheck(hammer2_chain_t *chain, void *bdata) 4002 { 4003 chain->bref.flags &= ~HAMMER2_BREF_FLAG_ZERO; 4004 4005 switch(HAMMER2_DEC_CHECK(chain->bref.methods)) { 4006 case HAMMER2_CHECK_NONE: 4007 break; 4008 case HAMMER2_CHECK_DISABLED: 4009 break; 4010 case HAMMER2_CHECK_ISCSI32: 4011 chain->bref.check.iscsi32.value = 4012 hammer2_icrc32(bdata, chain->bytes); 4013 break; 4014 case HAMMER2_CHECK_CRC64: 4015 chain->bref.check.crc64.value = 0; 4016 /* XXX */ 4017 break; 4018 case HAMMER2_CHECK_SHA192: 4019 { 4020 SHA256_CTX hash_ctx; 4021 union { 4022 uint8_t digest[SHA256_DIGEST_LENGTH]; 4023 uint64_t digest64[SHA256_DIGEST_LENGTH/8]; 4024 } u; 4025 4026 SHA256_Init(&hash_ctx); 4027 SHA256_Update(&hash_ctx, bdata, chain->bytes); 4028 SHA256_Final(u.digest, &hash_ctx); 4029 u.digest64[2] ^= u.digest64[3]; 4030 bcopy(u.digest, 4031 chain->bref.check.sha192.data, 4032 sizeof(chain->bref.check.sha192.data)); 4033 } 4034 break; 4035 case HAMMER2_CHECK_FREEMAP: 4036 chain->bref.check.freemap.icrc32 = 4037 hammer2_icrc32(bdata, chain->bytes); 4038 break; 4039 default: 4040 kprintf("hammer2_chain_setcheck: unknown check type %02x\n", 4041 chain->bref.methods); 4042 break; 4043 } 4044 } 4045 4046 int 4047 hammer2_chain_testcheck(hammer2_chain_t *chain, void *bdata) 4048 { 4049 int r; 4050 4051 if (chain->bref.flags & HAMMER2_BREF_FLAG_ZERO) 4052 return 1; 4053 4054 switch(HAMMER2_DEC_CHECK(chain->bref.methods)) { 4055 case HAMMER2_CHECK_NONE: 4056 r = 1; 4057 break; 4058 case HAMMER2_CHECK_DISABLED: 4059 r = 1; 4060 break; 4061 case HAMMER2_CHECK_ISCSI32: 4062 r = (chain->bref.check.iscsi32.value == 4063 hammer2_icrc32(bdata, chain->bytes)); 4064 break; 4065 case HAMMER2_CHECK_CRC64: 4066 r = (chain->bref.check.crc64.value == 0); 4067 /* XXX */ 4068 break; 4069 case HAMMER2_CHECK_SHA192: 4070 { 4071 SHA256_CTX hash_ctx; 4072 union { 4073 uint8_t digest[SHA256_DIGEST_LENGTH]; 4074 uint64_t digest64[SHA256_DIGEST_LENGTH/8]; 4075 } u; 4076 4077 SHA256_Init(&hash_ctx); 4078 SHA256_Update(&hash_ctx, bdata, chain->bytes); 4079 SHA256_Final(u.digest, &hash_ctx); 4080 u.digest64[2] ^= u.digest64[3]; 4081 if (bcmp(u.digest, 4082 chain->bref.check.sha192.data, 4083 sizeof(chain->bref.check.sha192.data)) == 0) { 4084 r = 1; 4085 } else { 4086 r = 0; 4087 } 4088 } 4089 break; 4090 case HAMMER2_CHECK_FREEMAP: 4091 r = (chain->bref.check.freemap.icrc32 == 4092 hammer2_icrc32(bdata, chain->bytes)); 4093 if (r == 0) { 4094 kprintf("freemap.icrc %08x icrc32 %08x (%d)\n", 4095 chain->bref.check.freemap.icrc32, 4096 hammer2_icrc32(bdata, chain->bytes), chain->bytes); 4097 if (chain->dio) 4098 kprintf("dio %p buf %016jx,%d bdata %p/%p\n", 4099 chain->dio, chain->dio->bp->b_loffset, chain->dio->bp->b_bufsize, bdata, chain->dio->bp->b_data); 4100 } 4101 4102 break; 4103 default: 4104 kprintf("hammer2_chain_setcheck: unknown check type %02x\n", 4105 chain->bref.methods); 4106 r = 1; 4107 break; 4108 } 4109 return r; 4110 } 4111 4112 /* 4113 * The caller presents a shared-locked (parent, chain) where the chain 4114 * is of type HAMMER2_OBJTYPE_HARDLINK. The caller must hold the ip 4115 * structure representing the inode locked to prevent 4116 * consolidation/deconsolidation races. 4117 * 4118 * We locate the hardlink in the current or a common parent directory. 4119 * 4120 * If we are unable to locate the hardlink, EIO is returned and 4121 * (*chainp) is unlocked and dropped. 4122 */ 4123 int 4124 hammer2_chain_hardlink_find(hammer2_inode_t *dip, 4125 hammer2_chain_t **parentp, 4126 hammer2_chain_t **chainp, 4127 int flags) 4128 { 4129 hammer2_chain_t *parent; 4130 hammer2_chain_t *rchain; 4131 hammer2_key_t key_dummy; 4132 hammer2_key_t lhc; 4133 int cache_index = -1; 4134 4135 /* 4136 * Obtain the key for the hardlink from *chainp. 4137 */ 4138 rchain = *chainp; 4139 lhc = rchain->data->ipdata.meta.inum; 4140 hammer2_chain_unlock(rchain); 4141 hammer2_chain_drop(rchain); 4142 rchain = NULL; 4143 4144 for (;;) { 4145 int nloops; 4146 rchain = hammer2_chain_lookup(parentp, &key_dummy, 4147 lhc, lhc, 4148 &cache_index, flags); 4149 if (rchain) 4150 break; 4151 4152 /* 4153 * Iterate parents, handle parent rename races by retrying 4154 * the operation. 4155 */ 4156 nloops = -1; 4157 while (nloops) { 4158 --nloops; 4159 parent = *parentp; 4160 if (nloops < 0 && 4161 parent->bref.type == HAMMER2_BREF_TYPE_INODE) { 4162 nloops = 1; 4163 } 4164 if (parent->bref.flags & HAMMER2_BREF_FLAG_PFSROOT) 4165 goto done; 4166 if (parent->parent == NULL) 4167 goto done; 4168 parent = parent->parent; 4169 hammer2_chain_ref(parent); 4170 hammer2_chain_unlock(*parentp); 4171 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS | 4172 flags); 4173 if ((*parentp)->parent == parent) { 4174 hammer2_chain_drop(*parentp); 4175 *parentp = parent; 4176 } else { 4177 hammer2_chain_unlock(parent); 4178 hammer2_chain_drop(parent); 4179 hammer2_chain_lock(*parentp, 4180 HAMMER2_RESOLVE_ALWAYS | 4181 flags); 4182 parent = NULL; /* safety */ 4183 /* retry */ 4184 } 4185 } 4186 } 4187 done: 4188 4189 *chainp = rchain; 4190 return (rchain ? EINVAL : 0); 4191 } 4192 4193 /* 4194 * Used by the bulkscan code to snapshot the synchronized storage for 4195 * a volume, allowing it to be scanned concurrently against normal 4196 * operation. 4197 */ 4198 hammer2_chain_t * 4199 hammer2_chain_bulksnap(hammer2_chain_t *chain) 4200 { 4201 hammer2_chain_t *copy; 4202 4203 copy = hammer2_chain_alloc(chain->hmp, chain->pmp, &chain->bref); 4204 switch(chain->bref.type) { 4205 case HAMMER2_BREF_TYPE_VOLUME: 4206 copy->data = kmalloc(sizeof(copy->data->voldata), 4207 chain->hmp->mchain, 4208 M_WAITOK | M_ZERO); 4209 hammer2_spin_ex(&chain->core.spin); 4210 copy->data->voldata = chain->data->voldata; 4211 hammer2_spin_unex(&chain->core.spin); 4212 break; 4213 case HAMMER2_BREF_TYPE_FREEMAP: 4214 copy->data = kmalloc(sizeof(hammer2_blockset_t), 4215 chain->hmp->mchain, 4216 M_WAITOK | M_ZERO); 4217 hammer2_spin_ex(&chain->core.spin); 4218 copy->data->blkset = chain->data->blkset; 4219 hammer2_spin_unex(&chain->core.spin); 4220 break; 4221 default: 4222 break; 4223 } 4224 return copy; 4225 } 4226 4227 void 4228 hammer2_chain_bulkdrop(hammer2_chain_t *copy) 4229 { 4230 switch(copy->bref.type) { 4231 case HAMMER2_BREF_TYPE_VOLUME: 4232 case HAMMER2_BREF_TYPE_FREEMAP: 4233 KKASSERT(copy->data); 4234 kfree(copy->data, copy->hmp->mchain); 4235 copy->data = NULL; 4236 default: 4237 break; 4238 } 4239 hammer2_chain_drop(copy); 4240 } 4241 4242 /* 4243 * Create a snapshot of the specified {parent, ochain} with the specified 4244 * label. The originating hammer2_inode must be exclusively locked for 4245 * safety. 4246 * 4247 * The ioctl code has already synced the filesystem. 4248 */ 4249 int 4250 hammer2_chain_snapshot(hammer2_chain_t *chain, hammer2_ioc_pfs_t *pmp, 4251 hammer2_tid_t mtid) 4252 { 4253 hammer2_dev_t *hmp; 4254 const hammer2_inode_data_t *ripdata; 4255 hammer2_inode_data_t *wipdata; 4256 hammer2_chain_t *nchain; 4257 hammer2_inode_t *nip; 4258 size_t name_len; 4259 hammer2_key_t lhc; 4260 struct vattr vat; 4261 #if 0 4262 uuid_t opfs_clid; 4263 #endif 4264 int error; 4265 4266 kprintf("snapshot %s\n", pmp->name); 4267 4268 name_len = strlen(pmp->name); 4269 lhc = hammer2_dirhash(pmp->name, name_len); 4270 4271 /* 4272 * Get the clid 4273 */ 4274 ripdata = &chain->data->ipdata; 4275 #if 0 4276 opfs_clid = ripdata->meta.pfs_clid; 4277 #endif 4278 hmp = chain->hmp; 4279 4280 /* 4281 * Create the snapshot directory under the super-root 4282 * 4283 * Set PFS type, generate a unique filesystem id, and generate 4284 * a cluster id. Use the same clid when snapshotting a PFS root, 4285 * which theoretically allows the snapshot to be used as part of 4286 * the same cluster (perhaps as a cache). 4287 * 4288 * Copy the (flushed) blockref array. Theoretically we could use 4289 * chain_duplicate() but it becomes difficult to disentangle 4290 * the shared core so for now just brute-force it. 4291 */ 4292 VATTR_NULL(&vat); 4293 vat.va_type = VDIR; 4294 vat.va_mode = 0755; 4295 nip = hammer2_inode_create(hmp->spmp->iroot, &vat, proc0.p_ucred, 4296 pmp->name, name_len, 0, 4297 1, 0, 0, 4298 HAMMER2_INSERT_PFSROOT, &error); 4299 4300 if (nip) { 4301 hammer2_inode_modify(nip); 4302 nchain = hammer2_inode_chain(nip, 0, HAMMER2_RESOLVE_ALWAYS); 4303 hammer2_chain_modify(nchain, mtid, 0, 0); 4304 wipdata = &nchain->data->ipdata; 4305 4306 nip->meta.pfs_type = HAMMER2_PFSTYPE_MASTER; 4307 nip->meta.pfs_subtype = HAMMER2_PFSSUBTYPE_SNAPSHOT; 4308 nip->meta.op_flags |= HAMMER2_OPFLAG_PFSROOT; 4309 kern_uuidgen(&nip->meta.pfs_fsid, 1); 4310 4311 /* 4312 * Give the snapshot its own private cluster id. As a 4313 * snapshot no further synchronization with the original 4314 * cluster will be done. 4315 */ 4316 #if 0 4317 if (chain->flags & HAMMER2_CHAIN_PFSBOUNDARY) 4318 nip->meta.pfs_clid = opfs_clid; 4319 else 4320 kern_uuidgen(&nip->meta.pfs_clid, 1); 4321 #endif 4322 kern_uuidgen(&nip->meta.pfs_clid, 1); 4323 nchain->bref.flags |= HAMMER2_BREF_FLAG_PFSROOT; 4324 4325 /* XXX hack blockset copy */ 4326 /* XXX doesn't work with real cluster */ 4327 wipdata->meta = nip->meta; 4328 wipdata->u.blockset = ripdata->u.blockset; 4329 hammer2_flush(nchain, 1); 4330 hammer2_chain_unlock(nchain); 4331 hammer2_chain_drop(nchain); 4332 hammer2_inode_unlock(nip); 4333 } 4334 return (error); 4335 } 4336