1 /* 2 * Copyright (c) 2007-2008 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * $DragonFly: src/sys/vfs/hammer/hammer_object.c,v 1.97 2008/09/23 22:28:56 dillon Exp $ 35 */ 36 37 #include "hammer.h" 38 39 static int hammer_mem_lookup(hammer_cursor_t cursor); 40 static int hammer_mem_first(hammer_cursor_t cursor); 41 static int hammer_frontend_trunc_callback(hammer_record_t record, 42 void *data __unused); 43 static int hammer_bulk_scan_callback(hammer_record_t record, void *data); 44 static int hammer_record_needs_overwrite_delete(hammer_record_t record); 45 static int hammer_delete_general(hammer_cursor_t cursor, hammer_inode_t ip, 46 hammer_btree_leaf_elm_t leaf); 47 48 struct rec_trunc_info { 49 u_int16_t rec_type; 50 int64_t trunc_off; 51 }; 52 53 struct hammer_bulk_info { 54 hammer_record_t record; 55 struct hammer_btree_leaf_elm leaf; 56 }; 57 58 /* 59 * Red-black tree support. Comparison code for insertion. 60 */ 61 static int 62 hammer_rec_rb_compare(hammer_record_t rec1, hammer_record_t rec2) 63 { 64 if (rec1->leaf.base.rec_type < rec2->leaf.base.rec_type) 65 return(-1); 66 if (rec1->leaf.base.rec_type > rec2->leaf.base.rec_type) 67 return(1); 68 69 if (rec1->leaf.base.key < rec2->leaf.base.key) 70 return(-1); 71 if (rec1->leaf.base.key > rec2->leaf.base.key) 72 return(1); 73 74 /* 75 * Never match against an item deleted by the front-end. 76 * 77 * rec1 is greater then rec2 if rec1 is marked deleted. 78 * rec1 is less then rec2 if rec2 is marked deleted. 79 * 80 * Multiple deleted records may be present, do not return 0 81 * if both are marked deleted. 82 */ 83 if (rec1->flags & HAMMER_RECF_DELETED_FE) 84 return(1); 85 if (rec2->flags & HAMMER_RECF_DELETED_FE) 86 return(-1); 87 88 return(0); 89 } 90 91 /* 92 * Basic record comparison code similar to hammer_btree_cmp(). 93 */ 94 static int 95 hammer_rec_cmp(hammer_base_elm_t elm, hammer_record_t rec) 96 { 97 if (elm->rec_type < rec->leaf.base.rec_type) 98 return(-3); 99 if (elm->rec_type > rec->leaf.base.rec_type) 100 return(3); 101 102 if (elm->key < rec->leaf.base.key) 103 return(-2); 104 if (elm->key > rec->leaf.base.key) 105 return(2); 106 107 /* 108 * Never match against an item deleted by the front-end. 109 * elm is less then rec if rec is marked deleted. 110 */ 111 if (rec->flags & HAMMER_RECF_DELETED_FE) 112 return(-1); 113 return(0); 114 } 115 116 /* 117 * Ranged scan to locate overlapping record(s). This is used by 118 * hammer_ip_get_bulk() to locate an overlapping record. We have 119 * to use a ranged scan because the keys for data records with the 120 * same file base offset can be different due to differing data_len's. 121 * 122 * NOTE: The base file offset of a data record is (key - data_len), not (key). 123 */ 124 static int 125 hammer_rec_overlap_cmp(hammer_record_t rec, void *data) 126 { 127 struct hammer_bulk_info *info = data; 128 hammer_btree_leaf_elm_t leaf = &info->leaf; 129 130 if (rec->leaf.base.rec_type < leaf->base.rec_type) 131 return(-3); 132 if (rec->leaf.base.rec_type > leaf->base.rec_type) 133 return(3); 134 135 /* 136 * Overlap compare 137 */ 138 if (leaf->base.rec_type == HAMMER_RECTYPE_DATA) { 139 /* rec_beg >= leaf_end */ 140 if (rec->leaf.base.key - rec->leaf.data_len >= leaf->base.key) 141 return(2); 142 /* rec_end <= leaf_beg */ 143 if (rec->leaf.base.key <= leaf->base.key - leaf->data_len) 144 return(-2); 145 } else { 146 if (rec->leaf.base.key < leaf->base.key) 147 return(-2); 148 if (rec->leaf.base.key > leaf->base.key) 149 return(2); 150 } 151 152 /* 153 * We have to return 0 at this point, even if DELETED_FE is set, 154 * because returning anything else will cause the scan to ignore 155 * one of the branches when we really want it to check both. 156 */ 157 return(0); 158 } 159 160 /* 161 * RB_SCAN comparison code for hammer_mem_first(). The argument order 162 * is reversed so the comparison result has to be negated. key_beg and 163 * key_end are both range-inclusive. 164 * 165 * Localized deletions are not cached in-memory. 166 */ 167 static 168 int 169 hammer_rec_scan_cmp(hammer_record_t rec, void *data) 170 { 171 hammer_cursor_t cursor = data; 172 int r; 173 174 r = hammer_rec_cmp(&cursor->key_beg, rec); 175 if (r > 1) 176 return(-1); 177 r = hammer_rec_cmp(&cursor->key_end, rec); 178 if (r < -1) 179 return(1); 180 return(0); 181 } 182 183 /* 184 * This compare function is used when simply looking up key_beg. 185 */ 186 static 187 int 188 hammer_rec_find_cmp(hammer_record_t rec, void *data) 189 { 190 hammer_cursor_t cursor = data; 191 int r; 192 193 r = hammer_rec_cmp(&cursor->key_beg, rec); 194 if (r > 1) 195 return(-1); 196 if (r < -1) 197 return(1); 198 return(0); 199 } 200 201 /* 202 * Locate blocks within the truncation range. Partial blocks do not count. 203 */ 204 static 205 int 206 hammer_rec_trunc_cmp(hammer_record_t rec, void *data) 207 { 208 struct rec_trunc_info *info = data; 209 210 if (rec->leaf.base.rec_type < info->rec_type) 211 return(-1); 212 if (rec->leaf.base.rec_type > info->rec_type) 213 return(1); 214 215 switch(rec->leaf.base.rec_type) { 216 case HAMMER_RECTYPE_DB: 217 /* 218 * DB record key is not beyond the truncation point, retain. 219 */ 220 if (rec->leaf.base.key < info->trunc_off) 221 return(-1); 222 break; 223 case HAMMER_RECTYPE_DATA: 224 /* 225 * DATA record offset start is not beyond the truncation point, 226 * retain. 227 */ 228 if (rec->leaf.base.key - rec->leaf.data_len < info->trunc_off) 229 return(-1); 230 break; 231 default: 232 panic("hammer_rec_trunc_cmp: unexpected record type"); 233 } 234 235 /* 236 * The record start is >= the truncation point, return match, 237 * the record should be destroyed. 238 */ 239 return(0); 240 } 241 242 RB_GENERATE(hammer_rec_rb_tree, hammer_record, rb_node, hammer_rec_rb_compare); 243 244 /* 245 * Allocate a record for the caller to finish filling in. The record is 246 * returned referenced. 247 */ 248 hammer_record_t 249 hammer_alloc_mem_record(hammer_inode_t ip, int data_len) 250 { 251 hammer_record_t record; 252 hammer_mount_t hmp; 253 254 hmp = ip->hmp; 255 ++hammer_count_records; 256 record = kmalloc(sizeof(*record), hmp->m_misc, 257 M_WAITOK | M_ZERO | M_USE_RESERVE); 258 record->flush_state = HAMMER_FST_IDLE; 259 record->ip = ip; 260 record->leaf.base.btype = HAMMER_BTREE_TYPE_RECORD; 261 record->leaf.data_len = data_len; 262 hammer_ref(&record->lock); 263 264 if (data_len) { 265 record->data = kmalloc(data_len, hmp->m_misc, M_WAITOK | M_ZERO); 266 record->flags |= HAMMER_RECF_ALLOCDATA; 267 ++hammer_count_record_datas; 268 } 269 270 return (record); 271 } 272 273 void 274 hammer_wait_mem_record_ident(hammer_record_t record, const char *ident) 275 { 276 while (record->flush_state == HAMMER_FST_FLUSH) { 277 record->flags |= HAMMER_RECF_WANTED; 278 tsleep(record, 0, ident, 0); 279 } 280 } 281 282 /* 283 * Called from the backend, hammer_inode.c, after a record has been 284 * flushed to disk. The record has been exclusively locked by the 285 * caller and interlocked with BE. 286 * 287 * We clean up the state, unlock, and release the record (the record 288 * was referenced by the fact that it was in the HAMMER_FST_FLUSH state). 289 */ 290 void 291 hammer_flush_record_done(hammer_record_t record, int error) 292 { 293 hammer_inode_t target_ip; 294 295 KKASSERT(record->flush_state == HAMMER_FST_FLUSH); 296 KKASSERT(record->flags & HAMMER_RECF_INTERLOCK_BE); 297 298 if (error) { 299 /* 300 * An error occured, the backend was unable to sync the 301 * record to its media. Leave the record intact. 302 */ 303 hammer_critical_error(record->ip->hmp, record->ip, error, 304 "while flushing record"); 305 } 306 307 --record->flush_group->refs; 308 record->flush_group = NULL; 309 310 if (record->flags & HAMMER_RECF_DELETED_BE) { 311 if ((target_ip = record->target_ip) != NULL) { 312 TAILQ_REMOVE(&target_ip->target_list, record, 313 target_entry); 314 record->target_ip = NULL; 315 hammer_test_inode(target_ip); 316 } 317 record->flush_state = HAMMER_FST_IDLE; 318 } else { 319 if (record->target_ip) { 320 record->flush_state = HAMMER_FST_SETUP; 321 hammer_test_inode(record->ip); 322 hammer_test_inode(record->target_ip); 323 } else { 324 record->flush_state = HAMMER_FST_IDLE; 325 } 326 } 327 record->flags &= ~HAMMER_RECF_INTERLOCK_BE; 328 if (record->flags & HAMMER_RECF_WANTED) { 329 record->flags &= ~HAMMER_RECF_WANTED; 330 wakeup(record); 331 } 332 hammer_rel_mem_record(record); 333 } 334 335 /* 336 * Release a memory record. Records marked for deletion are immediately 337 * removed from the RB-Tree but otherwise left intact until the last ref 338 * goes away. 339 */ 340 void 341 hammer_rel_mem_record(struct hammer_record *record) 342 { 343 hammer_mount_t hmp; 344 hammer_reserve_t resv; 345 hammer_inode_t ip; 346 hammer_inode_t target_ip; 347 348 hammer_unref(&record->lock); 349 350 if (record->lock.refs == 0) { 351 /* 352 * Upon release of the last reference wakeup any waiters. 353 * The record structure may get destroyed so callers will 354 * loop up and do a relookup. 355 * 356 * WARNING! Record must be removed from RB-TREE before we 357 * might possibly block. hammer_test_inode() can block! 358 */ 359 ip = record->ip; 360 hmp = ip->hmp; 361 362 /* 363 * Upon release of the last reference a record marked deleted 364 * is destroyed. 365 */ 366 if (record->flags & HAMMER_RECF_DELETED_FE) { 367 KKASSERT(ip->lock.refs > 0); 368 KKASSERT(record->flush_state != HAMMER_FST_FLUSH); 369 370 /* 371 * target_ip may have zero refs, we have to ref it 372 * to prevent it from being ripped out from under 373 * us. 374 */ 375 if ((target_ip = record->target_ip) != NULL) { 376 TAILQ_REMOVE(&target_ip->target_list, 377 record, target_entry); 378 record->target_ip = NULL; 379 hammer_ref(&target_ip->lock); 380 } 381 382 if (record->flags & HAMMER_RECF_ONRBTREE) { 383 RB_REMOVE(hammer_rec_rb_tree, 384 &record->ip->rec_tree, 385 record); 386 KKASSERT(ip->rsv_recs > 0); 387 --hmp->rsv_recs; 388 --ip->rsv_recs; 389 hmp->rsv_databytes -= record->leaf.data_len; 390 record->flags &= ~HAMMER_RECF_ONRBTREE; 391 392 if (RB_EMPTY(&record->ip->rec_tree)) { 393 record->ip->flags &= ~HAMMER_INODE_XDIRTY; 394 record->ip->sync_flags &= ~HAMMER_INODE_XDIRTY; 395 hammer_test_inode(record->ip); 396 } 397 } 398 399 /* 400 * We must wait for any direct-IO to complete before 401 * we can destroy the record because the bio may 402 * have a reference to it. 403 */ 404 if (record->flags & 405 (HAMMER_RECF_DIRECT_IO | HAMMER_RECF_DIRECT_INVAL)) { 406 hammer_io_direct_wait(record); 407 } 408 409 410 /* 411 * Do this test after removing record from the B-Tree. 412 */ 413 if (target_ip) { 414 hammer_test_inode(target_ip); 415 hammer_rel_inode(target_ip, 0); 416 } 417 418 if (record->flags & HAMMER_RECF_ALLOCDATA) { 419 --hammer_count_record_datas; 420 kfree(record->data, hmp->m_misc); 421 record->flags &= ~HAMMER_RECF_ALLOCDATA; 422 } 423 424 /* 425 * Release the reservation. If the record was not 426 * committed return the reservation before 427 * releasing it. 428 */ 429 if ((resv = record->resv) != NULL) { 430 #if 0 431 if ((record->flags & HAMMER_RECF_COMMITTED) == 0) { 432 hammer_blockmap_reserve_undo( 433 hmp, resv, 434 record->leaf.data_offset, 435 record->leaf.data_len); 436 } 437 #endif 438 hammer_blockmap_reserve_complete(hmp, resv); 439 record->resv = NULL; 440 } 441 record->data = NULL; 442 --hammer_count_records; 443 kfree(record, hmp->m_misc); 444 } 445 } 446 } 447 448 /* 449 * Record visibility depends on whether the record is being accessed by 450 * the backend or the frontend. 451 * 452 * Return non-zero if the record is visible, zero if it isn't or if it is 453 * deleted. 454 * 455 * If HAMMER_CURSOR_DELETE_VISIBILITY is set we allow deleted memory 456 * records to be returned. This is so pending deletions are detected 457 * when using an iterator to locate an unused hash key, or when we need 458 * to locate historical records on-disk to destroy. 459 */ 460 static __inline 461 int 462 hammer_ip_iterate_mem_good(hammer_cursor_t cursor, hammer_record_t record) 463 { 464 if (cursor->flags & HAMMER_CURSOR_DELETE_VISIBILITY) 465 return(1); 466 if (cursor->flags & HAMMER_CURSOR_BACKEND) { 467 if (record->flags & HAMMER_RECF_DELETED_BE) 468 return(0); 469 } else { 470 if (record->flags & HAMMER_RECF_DELETED_FE) 471 return(0); 472 } 473 return(1); 474 } 475 476 /* 477 * This callback is used as part of the RB_SCAN function for in-memory 478 * records. We terminate it (return -1) as soon as we get a match. 479 * 480 * This routine is used by frontend code. 481 * 482 * The primary compare code does not account for ASOF lookups. This 483 * code handles that case as well as a few others. 484 */ 485 static 486 int 487 hammer_rec_scan_callback(hammer_record_t rec, void *data) 488 { 489 hammer_cursor_t cursor = data; 490 491 /* 492 * We terminate on success, so this should be NULL on entry. 493 */ 494 KKASSERT(cursor->iprec == NULL); 495 496 /* 497 * Skip if the record was marked deleted. 498 */ 499 if (hammer_ip_iterate_mem_good(cursor, rec) == 0) 500 return(0); 501 502 /* 503 * Skip if not visible due to our as-of TID 504 */ 505 if (cursor->flags & HAMMER_CURSOR_ASOF) { 506 if (cursor->asof < rec->leaf.base.create_tid) 507 return(0); 508 if (rec->leaf.base.delete_tid && 509 cursor->asof >= rec->leaf.base.delete_tid) { 510 return(0); 511 } 512 } 513 514 /* 515 * ref the record. The record is protected from backend B-Tree 516 * interactions by virtue of the cursor's IP lock. 517 */ 518 hammer_ref(&rec->lock); 519 520 /* 521 * The record may have been deleted while we were blocked. 522 */ 523 if (hammer_ip_iterate_mem_good(cursor, rec) == 0) { 524 hammer_rel_mem_record(rec); 525 return(0); 526 } 527 528 /* 529 * Set the matching record and stop the scan. 530 */ 531 cursor->iprec = rec; 532 return(-1); 533 } 534 535 536 /* 537 * Lookup an in-memory record given the key specified in the cursor. Works 538 * just like hammer_btree_lookup() but operates on an inode's in-memory 539 * record list. 540 * 541 * The lookup must fail if the record is marked for deferred deletion. 542 */ 543 static 544 int 545 hammer_mem_lookup(hammer_cursor_t cursor) 546 { 547 int error; 548 549 KKASSERT(cursor->ip); 550 if (cursor->iprec) { 551 hammer_rel_mem_record(cursor->iprec); 552 cursor->iprec = NULL; 553 } 554 hammer_rec_rb_tree_RB_SCAN(&cursor->ip->rec_tree, hammer_rec_find_cmp, 555 hammer_rec_scan_callback, cursor); 556 557 if (cursor->iprec == NULL) 558 error = ENOENT; 559 else 560 error = 0; 561 return(error); 562 } 563 564 /* 565 * hammer_mem_first() - locate the first in-memory record matching the 566 * cursor within the bounds of the key range. 567 */ 568 static 569 int 570 hammer_mem_first(hammer_cursor_t cursor) 571 { 572 hammer_inode_t ip; 573 574 ip = cursor->ip; 575 KKASSERT(ip != NULL); 576 577 if (cursor->iprec) { 578 hammer_rel_mem_record(cursor->iprec); 579 cursor->iprec = NULL; 580 } 581 582 hammer_rec_rb_tree_RB_SCAN(&ip->rec_tree, hammer_rec_scan_cmp, 583 hammer_rec_scan_callback, cursor); 584 585 /* 586 * Adjust scan.node and keep it linked into the RB-tree so we can 587 * hold the cursor through third party modifications of the RB-tree. 588 */ 589 if (cursor->iprec) 590 return(0); 591 return(ENOENT); 592 } 593 594 /************************************************************************ 595 * HAMMER IN-MEMORY RECORD FUNCTIONS * 596 ************************************************************************ 597 * 598 * These functions manipulate in-memory records. Such records typically 599 * exist prior to being committed to disk or indexed via the on-disk B-Tree. 600 */ 601 602 /* 603 * Add a directory entry (dip,ncp) which references inode (ip). 604 * 605 * Note that the low 32 bits of the namekey are set temporarily to create 606 * a unique in-memory record, and may be modified a second time when the 607 * record is synchronized to disk. In particular, the low 32 bits cannot be 608 * all 0's when synching to disk, which is not handled here. 609 * 610 * NOTE: bytes does not include any terminating \0 on name, and name might 611 * not be terminated. 612 */ 613 int 614 hammer_ip_add_directory(struct hammer_transaction *trans, 615 struct hammer_inode *dip, const char *name, int bytes, 616 struct hammer_inode *ip) 617 { 618 struct hammer_cursor cursor; 619 hammer_record_t record; 620 int error; 621 u_int32_t max_iterations; 622 623 record = hammer_alloc_mem_record(dip, HAMMER_ENTRY_SIZE(bytes)); 624 625 record->type = HAMMER_MEM_RECORD_ADD; 626 record->leaf.base.localization = dip->obj_localization + 627 HAMMER_LOCALIZE_MISC; 628 record->leaf.base.obj_id = dip->obj_id; 629 record->leaf.base.key = hammer_directory_namekey(dip, name, bytes, 630 &max_iterations); 631 record->leaf.base.rec_type = HAMMER_RECTYPE_DIRENTRY; 632 record->leaf.base.obj_type = ip->ino_leaf.base.obj_type; 633 record->data->entry.obj_id = ip->obj_id; 634 record->data->entry.localization = ip->obj_localization; 635 bcopy(name, record->data->entry.name, bytes); 636 637 ++ip->ino_data.nlinks; 638 hammer_modify_inode(ip, HAMMER_INODE_DDIRTY); 639 640 /* 641 * Find an unused namekey. Both the in-memory record tree and 642 * the B-Tree are checked. We do not want historically deleted 643 * names to create a collision as our iteration space may be limited, 644 * and since create_tid wouldn't match anyway an ASOF search 645 * must be used to locate collisions. 646 * 647 * delete-visibility is set so pending deletions do not give us 648 * a false-negative on our ability to use an iterator. 649 * 650 * The iterator must not rollover the key. Directory keys only 651 * use the positive key space. 652 */ 653 hammer_init_cursor(trans, &cursor, &dip->cache[1], dip); 654 cursor.key_beg = record->leaf.base; 655 cursor.flags |= HAMMER_CURSOR_ASOF; 656 cursor.flags |= HAMMER_CURSOR_DELETE_VISIBILITY; 657 cursor.asof = ip->obj_asof; 658 659 while (hammer_ip_lookup(&cursor) == 0) { 660 ++record->leaf.base.key; 661 KKASSERT(record->leaf.base.key > 0); 662 cursor.key_beg.key = record->leaf.base.key; 663 if (--max_iterations == 0) { 664 hammer_rel_mem_record(record); 665 error = ENOSPC; 666 goto failed; 667 } 668 } 669 670 /* 671 * The target inode and the directory entry are bound together. 672 */ 673 record->target_ip = ip; 674 record->flush_state = HAMMER_FST_SETUP; 675 TAILQ_INSERT_TAIL(&ip->target_list, record, target_entry); 676 677 /* 678 * The inode now has a dependancy and must be taken out of the idle 679 * state. An inode not in an idle state is given an extra reference. 680 * 681 * When transitioning to a SETUP state flag for an automatic reflush 682 * when the dependancies are disposed of if someone is waiting on 683 * the inode. 684 */ 685 if (ip->flush_state == HAMMER_FST_IDLE) { 686 hammer_ref(&ip->lock); 687 ip->flush_state = HAMMER_FST_SETUP; 688 if (ip->flags & HAMMER_INODE_FLUSHW) 689 ip->flags |= HAMMER_INODE_REFLUSH; 690 } 691 error = hammer_mem_add(record); 692 if (error == 0) { 693 dip->ino_data.mtime = trans->time; 694 hammer_modify_inode(dip, HAMMER_INODE_MTIME); 695 } 696 failed: 697 hammer_done_cursor(&cursor); 698 return(error); 699 } 700 701 /* 702 * Delete the directory entry and update the inode link count. The 703 * cursor must be seeked to the directory entry record being deleted. 704 * 705 * The related inode should be share-locked by the caller. The caller is 706 * on the frontend. 707 * 708 * This function can return EDEADLK requiring the caller to terminate 709 * the cursor, any locks, wait on the returned record, and retry. 710 */ 711 int 712 hammer_ip_del_directory(struct hammer_transaction *trans, 713 hammer_cursor_t cursor, struct hammer_inode *dip, 714 struct hammer_inode *ip) 715 { 716 hammer_record_t record; 717 int error; 718 719 if (hammer_cursor_inmem(cursor)) { 720 /* 721 * In-memory (unsynchronized) records can simply be freed. 722 * Even though the HAMMER_RECF_DELETED_FE flag is ignored 723 * by the backend, we must still avoid races against the 724 * backend potentially syncing the record to the media. 725 * 726 * We cannot call hammer_ip_delete_record(), that routine may 727 * only be called from the backend. 728 */ 729 record = cursor->iprec; 730 if (record->flags & HAMMER_RECF_INTERLOCK_BE) { 731 KKASSERT(cursor->deadlk_rec == NULL); 732 hammer_ref(&record->lock); 733 cursor->deadlk_rec = record; 734 error = EDEADLK; 735 } else { 736 KKASSERT(record->type == HAMMER_MEM_RECORD_ADD); 737 record->flags |= HAMMER_RECF_DELETED_FE; 738 error = 0; 739 } 740 } else { 741 /* 742 * If the record is on-disk we have to queue the deletion by 743 * the record's key. This also causes lookups to skip the 744 * record. 745 */ 746 KKASSERT(dip->flags & 747 (HAMMER_INODE_ONDISK | HAMMER_INODE_DONDISK)); 748 record = hammer_alloc_mem_record(dip, 0); 749 record->type = HAMMER_MEM_RECORD_DEL; 750 record->leaf.base = cursor->leaf->base; 751 752 record->target_ip = ip; 753 record->flush_state = HAMMER_FST_SETUP; 754 TAILQ_INSERT_TAIL(&ip->target_list, record, target_entry); 755 756 /* 757 * The inode now has a dependancy and must be taken out of 758 * the idle state. An inode not in an idle state is given 759 * an extra reference. 760 * 761 * When transitioning to a SETUP state flag for an automatic 762 * reflush when the dependancies are disposed of if someone 763 * is waiting on the inode. 764 */ 765 if (ip->flush_state == HAMMER_FST_IDLE) { 766 hammer_ref(&ip->lock); 767 ip->flush_state = HAMMER_FST_SETUP; 768 if (ip->flags & HAMMER_INODE_FLUSHW) 769 ip->flags |= HAMMER_INODE_REFLUSH; 770 } 771 772 error = hammer_mem_add(record); 773 } 774 775 /* 776 * One less link. The file may still be open in the OS even after 777 * all links have gone away. 778 * 779 * We have to terminate the cursor before syncing the inode to 780 * avoid deadlocking against ourselves. XXX this may no longer 781 * be true. 782 * 783 * If nlinks drops to zero and the vnode is inactive (or there is 784 * no vnode), call hammer_inode_unloadable_check() to zonk the 785 * inode. If we don't do this here the inode will not be destroyed 786 * on-media until we unmount. 787 */ 788 if (error == 0) { 789 --ip->ino_data.nlinks; 790 dip->ino_data.mtime = trans->time; 791 hammer_modify_inode(dip, HAMMER_INODE_MTIME); 792 hammer_modify_inode(ip, HAMMER_INODE_DDIRTY); 793 if (ip->ino_data.nlinks == 0 && 794 (ip->vp == NULL || (ip->vp->v_flag & VINACTIVE))) { 795 hammer_done_cursor(cursor); 796 hammer_inode_unloadable_check(ip, 1); 797 hammer_flush_inode(ip, 0); 798 } 799 800 } 801 return(error); 802 } 803 804 /* 805 * Add a record to an inode. 806 * 807 * The caller must allocate the record with hammer_alloc_mem_record(ip) and 808 * initialize the following additional fields: 809 * 810 * The related inode should be share-locked by the caller. The caller is 811 * on the frontend. 812 * 813 * record->rec.entry.base.base.key 814 * record->rec.entry.base.base.rec_type 815 * record->rec.entry.base.base.data_len 816 * record->data (a copy will be kmalloc'd if it cannot be embedded) 817 */ 818 int 819 hammer_ip_add_record(struct hammer_transaction *trans, hammer_record_t record) 820 { 821 hammer_inode_t ip = record->ip; 822 int error; 823 824 KKASSERT(record->leaf.base.localization != 0); 825 record->leaf.base.obj_id = ip->obj_id; 826 record->leaf.base.obj_type = ip->ino_leaf.base.obj_type; 827 error = hammer_mem_add(record); 828 return(error); 829 } 830 831 /* 832 * Locate a bulk record in-memory. Bulk records allow disk space to be 833 * reserved so the front-end can flush large data writes without having 834 * to queue the BIO to the flusher. Only the related record gets queued 835 * to the flusher. 836 */ 837 838 static hammer_record_t 839 hammer_ip_get_bulk(hammer_inode_t ip, off_t file_offset, int bytes) 840 { 841 struct hammer_bulk_info info; 842 843 bzero(&info, sizeof(info)); 844 info.leaf.base.obj_id = ip->obj_id; 845 info.leaf.base.key = file_offset + bytes; 846 info.leaf.base.create_tid = 0; 847 info.leaf.base.delete_tid = 0; 848 info.leaf.base.rec_type = HAMMER_RECTYPE_DATA; 849 info.leaf.base.obj_type = 0; /* unused */ 850 info.leaf.base.btype = HAMMER_BTREE_TYPE_RECORD; /* unused */ 851 info.leaf.base.localization = ip->obj_localization + /* unused */ 852 HAMMER_LOCALIZE_MISC; 853 info.leaf.data_len = bytes; 854 855 hammer_rec_rb_tree_RB_SCAN(&ip->rec_tree, hammer_rec_overlap_cmp, 856 hammer_bulk_scan_callback, &info); 857 858 return(info.record); /* may be NULL */ 859 } 860 861 /* 862 * Take records vetted by overlap_cmp. The first non-deleted record 863 * (if any) stops the scan. 864 */ 865 static int 866 hammer_bulk_scan_callback(hammer_record_t record, void *data) 867 { 868 struct hammer_bulk_info *info = data; 869 870 if (record->flags & HAMMER_RECF_DELETED_FE) 871 return(0); 872 hammer_ref(&record->lock); 873 info->record = record; 874 return(-1); /* stop scan */ 875 } 876 877 /* 878 * Reserve blockmap space placemarked with an in-memory record. 879 * 880 * This routine is called by the frontend in order to be able to directly 881 * flush a buffer cache buffer. The frontend has locked the related buffer 882 * cache buffers and we should be able to manipulate any overlapping 883 * in-memory records. 884 * 885 * The caller is responsible for adding the returned record. 886 */ 887 hammer_record_t 888 hammer_ip_add_bulk(hammer_inode_t ip, off_t file_offset, void *data, int bytes, 889 int *errorp) 890 { 891 hammer_record_t record; 892 hammer_record_t conflict; 893 int zone; 894 895 /* 896 * Deal with conflicting in-memory records. We cannot have multiple 897 * in-memory records for the same base offset without seriously 898 * confusing the backend, including but not limited to the backend 899 * issuing delete-create-delete or create-delete-create sequences 900 * and asserting on the delete_tid being the same as the create_tid. 901 * 902 * If we encounter a record with the backend interlock set we cannot 903 * immediately delete it without confusing the backend. 904 */ 905 while ((conflict = hammer_ip_get_bulk(ip, file_offset, bytes)) !=NULL) { 906 if (conflict->flags & HAMMER_RECF_INTERLOCK_BE) { 907 conflict->flags |= HAMMER_RECF_WANTED; 908 tsleep(conflict, 0, "hmrrc3", 0); 909 } else { 910 conflict->flags |= HAMMER_RECF_DELETED_FE; 911 } 912 hammer_rel_mem_record(conflict); 913 } 914 915 /* 916 * Create a record to cover the direct write. This is called with 917 * the related BIO locked so there should be no possible conflict. 918 * 919 * The backend is responsible for finalizing the space reserved in 920 * this record. 921 * 922 * XXX bytes not aligned, depend on the reservation code to 923 * align the reservation. 924 */ 925 record = hammer_alloc_mem_record(ip, 0); 926 zone = (bytes >= HAMMER_BUFSIZE) ? HAMMER_ZONE_LARGE_DATA_INDEX : 927 HAMMER_ZONE_SMALL_DATA_INDEX; 928 record->resv = hammer_blockmap_reserve(ip->hmp, zone, bytes, 929 &record->leaf.data_offset, 930 errorp); 931 if (record->resv == NULL) { 932 kprintf("hammer_ip_add_bulk: reservation failed\n"); 933 hammer_rel_mem_record(record); 934 return(NULL); 935 } 936 record->type = HAMMER_MEM_RECORD_DATA; 937 record->leaf.base.rec_type = HAMMER_RECTYPE_DATA; 938 record->leaf.base.obj_type = ip->ino_leaf.base.obj_type; 939 record->leaf.base.obj_id = ip->obj_id; 940 record->leaf.base.key = file_offset + bytes; 941 record->leaf.base.localization = ip->obj_localization + 942 HAMMER_LOCALIZE_MISC; 943 record->leaf.data_len = bytes; 944 hammer_crc_set_leaf(data, &record->leaf); 945 KKASSERT(*errorp == 0); 946 return(record); 947 } 948 949 /* 950 * Frontend truncation code. Scan in-memory records only. On-disk records 951 * and records in a flushing state are handled by the backend. The vnops 952 * setattr code will handle the block containing the truncation point. 953 * 954 * Partial blocks are not deleted. 955 */ 956 int 957 hammer_ip_frontend_trunc(struct hammer_inode *ip, off_t file_size) 958 { 959 struct rec_trunc_info info; 960 961 switch(ip->ino_data.obj_type) { 962 case HAMMER_OBJTYPE_REGFILE: 963 info.rec_type = HAMMER_RECTYPE_DATA; 964 break; 965 case HAMMER_OBJTYPE_DBFILE: 966 info.rec_type = HAMMER_RECTYPE_DB; 967 break; 968 default: 969 return(EINVAL); 970 } 971 info.trunc_off = file_size; 972 hammer_rec_rb_tree_RB_SCAN(&ip->rec_tree, hammer_rec_trunc_cmp, 973 hammer_frontend_trunc_callback, &info); 974 return(0); 975 } 976 977 static int 978 hammer_frontend_trunc_callback(hammer_record_t record, void *data __unused) 979 { 980 if (record->flags & HAMMER_RECF_DELETED_FE) 981 return(0); 982 if (record->flush_state == HAMMER_FST_FLUSH) 983 return(0); 984 KKASSERT((record->flags & HAMMER_RECF_INTERLOCK_BE) == 0); 985 hammer_ref(&record->lock); 986 record->flags |= HAMMER_RECF_DELETED_FE; 987 hammer_rel_mem_record(record); 988 return(0); 989 } 990 991 /* 992 * Return 1 if the caller must check for and delete existing records 993 * before writing out a new data record. 994 * 995 * Return 0 if the caller can just insert the record into the B-Tree without 996 * checking. 997 */ 998 static int 999 hammer_record_needs_overwrite_delete(hammer_record_t record) 1000 { 1001 hammer_inode_t ip = record->ip; 1002 int64_t file_offset; 1003 int r; 1004 1005 if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) 1006 file_offset = record->leaf.base.key; 1007 else 1008 file_offset = record->leaf.base.key - record->leaf.data_len; 1009 r = (file_offset < ip->save_trunc_off); 1010 if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) { 1011 if (ip->save_trunc_off <= record->leaf.base.key) 1012 ip->save_trunc_off = record->leaf.base.key + 1; 1013 } else { 1014 if (ip->save_trunc_off < record->leaf.base.key) 1015 ip->save_trunc_off = record->leaf.base.key; 1016 } 1017 return(r); 1018 } 1019 1020 /* 1021 * Backend code. Sync a record to the media. 1022 */ 1023 int 1024 hammer_ip_sync_record_cursor(hammer_cursor_t cursor, hammer_record_t record) 1025 { 1026 hammer_transaction_t trans = cursor->trans; 1027 int64_t file_offset; 1028 int bytes; 1029 void *bdata; 1030 int error; 1031 int doprop; 1032 1033 KKASSERT(record->flush_state == HAMMER_FST_FLUSH); 1034 KKASSERT(record->flags & HAMMER_RECF_INTERLOCK_BE); 1035 KKASSERT(record->leaf.base.localization != 0); 1036 1037 /* 1038 * Any direct-write related to the record must complete before we 1039 * can sync the record to the on-disk media. 1040 */ 1041 if (record->flags & (HAMMER_RECF_DIRECT_IO | HAMMER_RECF_DIRECT_INVAL)) 1042 hammer_io_direct_wait(record); 1043 1044 /* 1045 * If this is a bulk-data record placemarker there may be an existing 1046 * record on-disk, indicating a data overwrite. If there is the 1047 * on-disk record must be deleted before we can insert our new record. 1048 * 1049 * We've synthesized this record and do not know what the create_tid 1050 * on-disk is, nor how much data it represents. 1051 * 1052 * Keep in mind that (key) for data records is (base_offset + len), 1053 * not (base_offset). Also, we only want to get rid of on-disk 1054 * records since we are trying to sync our in-memory record, call 1055 * hammer_ip_delete_range() with truncating set to 1 to make sure 1056 * it skips in-memory records. 1057 * 1058 * It is ok for the lookup to return ENOENT. 1059 * 1060 * NOTE OPTIMIZATION: sync_trunc_off is used to determine if we have 1061 * to call hammer_ip_delete_range() or not. This also means we must 1062 * update sync_trunc_off() as we write. 1063 */ 1064 if (record->type == HAMMER_MEM_RECORD_DATA && 1065 hammer_record_needs_overwrite_delete(record)) { 1066 file_offset = record->leaf.base.key - record->leaf.data_len; 1067 bytes = (record->leaf.data_len + HAMMER_BUFMASK) & 1068 ~HAMMER_BUFMASK; 1069 KKASSERT((file_offset & HAMMER_BUFMASK) == 0); 1070 error = hammer_ip_delete_range( 1071 cursor, record->ip, 1072 file_offset, file_offset + bytes - 1, 1073 1); 1074 if (error && error != ENOENT) 1075 goto done; 1076 } 1077 1078 /* 1079 * If this is a general record there may be an on-disk version 1080 * that must be deleted before we can insert the new record. 1081 */ 1082 if (record->type == HAMMER_MEM_RECORD_GENERAL) { 1083 error = hammer_delete_general(cursor, record->ip, 1084 &record->leaf); 1085 if (error && error != ENOENT) 1086 goto done; 1087 } 1088 1089 /* 1090 * Setup the cursor. 1091 */ 1092 hammer_normalize_cursor(cursor); 1093 cursor->key_beg = record->leaf.base; 1094 cursor->flags &= ~HAMMER_CURSOR_INITMASK; 1095 cursor->flags |= HAMMER_CURSOR_BACKEND; 1096 cursor->flags &= ~HAMMER_CURSOR_INSERT; 1097 1098 /* 1099 * Records can wind up on-media before the inode itself is on-media. 1100 * Flag the case. 1101 */ 1102 record->ip->flags |= HAMMER_INODE_DONDISK; 1103 1104 /* 1105 * If we are deleting a directory entry an exact match must be 1106 * found on-disk. 1107 */ 1108 if (record->type == HAMMER_MEM_RECORD_DEL) { 1109 error = hammer_btree_lookup(cursor); 1110 if (error == 0) { 1111 KKASSERT(cursor->iprec == NULL); 1112 error = hammer_ip_delete_record(cursor, record->ip, 1113 trans->tid); 1114 if (error == 0) { 1115 record->flags |= HAMMER_RECF_DELETED_FE; 1116 record->flags |= HAMMER_RECF_DELETED_BE; 1117 record->flags |= HAMMER_RECF_COMMITTED; 1118 } 1119 } 1120 goto done; 1121 } 1122 1123 /* 1124 * We are inserting. 1125 * 1126 * Issue a lookup to position the cursor and locate the cluster. The 1127 * target key should not exist. If we are creating a directory entry 1128 * we may have to iterate the low 32 bits of the key to find an unused 1129 * key. 1130 */ 1131 hammer_sync_lock_sh(trans); 1132 cursor->flags |= HAMMER_CURSOR_INSERT; 1133 error = hammer_btree_lookup(cursor); 1134 if (hammer_debug_inode) 1135 kprintf("DOINSERT LOOKUP %d\n", error); 1136 if (error == 0) { 1137 kprintf("hammer_ip_sync_record: duplicate rec " 1138 "at (%016llx)\n", record->leaf.base.key); 1139 Debugger("duplicate record1"); 1140 error = EIO; 1141 } 1142 #if 0 1143 if (record->type == HAMMER_MEM_RECORD_DATA) 1144 kprintf("sync_record %016llx ---------------- %016llx %d\n", 1145 record->leaf.base.key - record->leaf.data_len, 1146 record->leaf.data_offset, error); 1147 #endif 1148 1149 if (error != ENOENT) 1150 goto done_unlock; 1151 1152 /* 1153 * Allocate the record and data. The result buffers will be 1154 * marked as being modified and further calls to 1155 * hammer_modify_buffer() will result in unneeded UNDO records. 1156 * 1157 * Support zero-fill records (data == NULL and data_len != 0) 1158 */ 1159 if (record->type == HAMMER_MEM_RECORD_DATA) { 1160 /* 1161 * The data portion of a bulk-data record has already been 1162 * committed to disk, we need only adjust the layer2 1163 * statistics in the same transaction as our B-Tree insert. 1164 */ 1165 KKASSERT(record->leaf.data_offset != 0); 1166 error = hammer_blockmap_finalize(trans, 1167 record->resv, 1168 record->leaf.data_offset, 1169 record->leaf.data_len); 1170 } else if (record->data && record->leaf.data_len) { 1171 /* 1172 * Wholely cached record, with data. Allocate the data. 1173 */ 1174 bdata = hammer_alloc_data(trans, record->leaf.data_len, 1175 record->leaf.base.rec_type, 1176 &record->leaf.data_offset, 1177 &cursor->data_buffer, &error); 1178 if (bdata == NULL) 1179 goto done_unlock; 1180 hammer_crc_set_leaf(record->data, &record->leaf); 1181 hammer_modify_buffer(trans, cursor->data_buffer, NULL, 0); 1182 bcopy(record->data, bdata, record->leaf.data_len); 1183 hammer_modify_buffer_done(cursor->data_buffer); 1184 } else { 1185 /* 1186 * Wholely cached record, without data. 1187 */ 1188 record->leaf.data_offset = 0; 1189 record->leaf.data_crc = 0; 1190 } 1191 1192 error = hammer_btree_insert(cursor, &record->leaf, &doprop); 1193 if (hammer_debug_inode && error) 1194 kprintf("BTREE INSERT error %d @ %016llx:%d key %016llx\n", error, cursor->node->node_offset, cursor->index, record->leaf.base.key); 1195 1196 /* 1197 * Our record is on-disk, normally mark the in-memory version as 1198 * deleted. If the record represented a directory deletion but 1199 * we had to sync a valid directory entry to disk we must convert 1200 * the record to a covering delete so the frontend does not have 1201 * visibility on the synced entry. 1202 */ 1203 if (error == 0) { 1204 if (doprop) { 1205 hammer_btree_do_propagation(cursor, 1206 record->ip->pfsm, 1207 &record->leaf); 1208 } 1209 if (record->flags & HAMMER_RECF_CONVERT_DELETE) { 1210 KKASSERT(record->type == HAMMER_MEM_RECORD_ADD); 1211 record->flags &= ~HAMMER_RECF_DELETED_FE; 1212 record->type = HAMMER_MEM_RECORD_DEL; 1213 KKASSERT(record->flush_state == HAMMER_FST_FLUSH); 1214 record->flags &= ~HAMMER_RECF_CONVERT_DELETE; 1215 /* hammer_flush_record_done takes care of the rest */ 1216 } else { 1217 record->flags |= HAMMER_RECF_DELETED_FE; 1218 record->flags |= HAMMER_RECF_DELETED_BE; 1219 } 1220 record->flags |= HAMMER_RECF_COMMITTED; 1221 } else { 1222 if (record->leaf.data_offset) { 1223 hammer_blockmap_free(trans, record->leaf.data_offset, 1224 record->leaf.data_len); 1225 } 1226 } 1227 done_unlock: 1228 hammer_sync_unlock(trans); 1229 done: 1230 return(error); 1231 } 1232 1233 /* 1234 * Add the record to the inode's rec_tree. The low 32 bits of a directory 1235 * entry's key is used to deal with hash collisions in the upper 32 bits. 1236 * A unique 64 bit key is generated in-memory and may be regenerated a 1237 * second time when the directory record is flushed to the on-disk B-Tree. 1238 * 1239 * A referenced record is passed to this function. This function 1240 * eats the reference. If an error occurs the record will be deleted. 1241 * 1242 * A copy of the temporary record->data pointer provided by the caller 1243 * will be made. 1244 */ 1245 int 1246 hammer_mem_add(hammer_record_t record) 1247 { 1248 hammer_mount_t hmp = record->ip->hmp; 1249 1250 /* 1251 * Make a private copy of record->data 1252 */ 1253 if (record->data) 1254 KKASSERT(record->flags & HAMMER_RECF_ALLOCDATA); 1255 1256 /* 1257 * Insert into the RB tree. A unique key should have already 1258 * been selected if this is a directory entry. 1259 */ 1260 if (RB_INSERT(hammer_rec_rb_tree, &record->ip->rec_tree, record)) { 1261 record->flags |= HAMMER_RECF_DELETED_FE; 1262 hammer_rel_mem_record(record); 1263 return (EEXIST); 1264 } 1265 ++hmp->count_newrecords; 1266 ++hmp->rsv_recs; 1267 ++record->ip->rsv_recs; 1268 record->ip->hmp->rsv_databytes += record->leaf.data_len; 1269 record->flags |= HAMMER_RECF_ONRBTREE; 1270 hammer_modify_inode(record->ip, HAMMER_INODE_XDIRTY); 1271 hammer_rel_mem_record(record); 1272 return(0); 1273 } 1274 1275 /************************************************************************ 1276 * HAMMER INODE MERGED-RECORD FUNCTIONS * 1277 ************************************************************************ 1278 * 1279 * These functions augment the B-Tree scanning functions in hammer_btree.c 1280 * by merging in-memory records with on-disk records. 1281 */ 1282 1283 /* 1284 * Locate a particular record either in-memory or on-disk. 1285 * 1286 * NOTE: This is basically a standalone routine, hammer_ip_next() may 1287 * NOT be called to iterate results. 1288 */ 1289 int 1290 hammer_ip_lookup(hammer_cursor_t cursor) 1291 { 1292 int error; 1293 1294 /* 1295 * If the element is in-memory return it without searching the 1296 * on-disk B-Tree 1297 */ 1298 KKASSERT(cursor->ip); 1299 error = hammer_mem_lookup(cursor); 1300 if (error == 0) { 1301 cursor->leaf = &cursor->iprec->leaf; 1302 return(error); 1303 } 1304 if (error != ENOENT) 1305 return(error); 1306 1307 /* 1308 * If the inode has on-disk components search the on-disk B-Tree. 1309 */ 1310 if ((cursor->ip->flags & (HAMMER_INODE_ONDISK|HAMMER_INODE_DONDISK)) == 0) 1311 return(error); 1312 error = hammer_btree_lookup(cursor); 1313 if (error == 0) 1314 error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_LEAF); 1315 return(error); 1316 } 1317 1318 /* 1319 * Locate the first record within the cursor's key_beg/key_end range, 1320 * restricted to a particular inode. 0 is returned on success, ENOENT 1321 * if no records matched the requested range, or some other error. 1322 * 1323 * When 0 is returned hammer_ip_next() may be used to iterate additional 1324 * records within the requested range. 1325 * 1326 * This function can return EDEADLK, requiring the caller to terminate 1327 * the cursor and try again. 1328 */ 1329 int 1330 hammer_ip_first(hammer_cursor_t cursor) 1331 { 1332 hammer_inode_t ip = cursor->ip; 1333 int error; 1334 1335 KKASSERT(ip != NULL); 1336 1337 /* 1338 * Clean up fields and setup for merged scan 1339 */ 1340 cursor->flags &= ~HAMMER_CURSOR_RETEST; 1341 cursor->flags |= HAMMER_CURSOR_ATEDISK | HAMMER_CURSOR_ATEMEM; 1342 cursor->flags |= HAMMER_CURSOR_DISKEOF | HAMMER_CURSOR_MEMEOF; 1343 if (cursor->iprec) { 1344 hammer_rel_mem_record(cursor->iprec); 1345 cursor->iprec = NULL; 1346 } 1347 1348 /* 1349 * Search the on-disk B-Tree. hammer_btree_lookup() only does an 1350 * exact lookup so if we get ENOENT we have to call the iterate 1351 * function to validate the first record after the begin key. 1352 * 1353 * The ATEDISK flag is used by hammer_btree_iterate to determine 1354 * whether it must index forwards or not. It is also used here 1355 * to select the next record from in-memory or on-disk. 1356 * 1357 * EDEADLK can only occur if the lookup hit an empty internal 1358 * element and couldn't delete it. Since this could only occur 1359 * in-range, we can just iterate from the failure point. 1360 */ 1361 if (ip->flags & (HAMMER_INODE_ONDISK|HAMMER_INODE_DONDISK)) { 1362 error = hammer_btree_lookup(cursor); 1363 if (error == ENOENT || error == EDEADLK) { 1364 cursor->flags &= ~HAMMER_CURSOR_ATEDISK; 1365 if (hammer_debug_general & 0x2000) 1366 kprintf("error %d node %p %016llx index %d\n", error, cursor->node, cursor->node->node_offset, cursor->index); 1367 error = hammer_btree_iterate(cursor); 1368 } 1369 if (error && error != ENOENT) 1370 return(error); 1371 if (error == 0) { 1372 cursor->flags &= ~HAMMER_CURSOR_DISKEOF; 1373 cursor->flags &= ~HAMMER_CURSOR_ATEDISK; 1374 } else { 1375 cursor->flags |= HAMMER_CURSOR_ATEDISK; 1376 } 1377 } 1378 1379 /* 1380 * Search the in-memory record list (Red-Black tree). Unlike the 1381 * B-Tree search, mem_first checks for records in the range. 1382 */ 1383 error = hammer_mem_first(cursor); 1384 if (error && error != ENOENT) 1385 return(error); 1386 if (error == 0) { 1387 cursor->flags &= ~HAMMER_CURSOR_MEMEOF; 1388 cursor->flags &= ~HAMMER_CURSOR_ATEMEM; 1389 if (hammer_ip_iterate_mem_good(cursor, cursor->iprec) == 0) 1390 cursor->flags |= HAMMER_CURSOR_ATEMEM; 1391 } 1392 1393 /* 1394 * This will return the first matching record. 1395 */ 1396 return(hammer_ip_next(cursor)); 1397 } 1398 1399 /* 1400 * Retrieve the next record in a merged iteration within the bounds of the 1401 * cursor. This call may be made multiple times after the cursor has been 1402 * initially searched with hammer_ip_first(). 1403 * 1404 * 0 is returned on success, ENOENT if no further records match the 1405 * requested range, or some other error code is returned. 1406 */ 1407 int 1408 hammer_ip_next(hammer_cursor_t cursor) 1409 { 1410 hammer_btree_elm_t elm; 1411 hammer_record_t rec, save; 1412 int error; 1413 int r; 1414 1415 next_btree: 1416 /* 1417 * Load the current on-disk and in-memory record. If we ate any 1418 * records we have to get the next one. 1419 * 1420 * If we deleted the last on-disk record we had scanned ATEDISK will 1421 * be clear and RETEST will be set, forcing a call to iterate. The 1422 * fact that ATEDISK is clear causes iterate to re-test the 'current' 1423 * element. If ATEDISK is set, iterate will skip the 'current' 1424 * element. 1425 * 1426 * Get the next on-disk record 1427 */ 1428 if (cursor->flags & (HAMMER_CURSOR_ATEDISK|HAMMER_CURSOR_RETEST)) { 1429 if ((cursor->flags & HAMMER_CURSOR_DISKEOF) == 0) { 1430 error = hammer_btree_iterate(cursor); 1431 cursor->flags &= ~HAMMER_CURSOR_RETEST; 1432 if (error == 0) { 1433 cursor->flags &= ~HAMMER_CURSOR_ATEDISK; 1434 hammer_cache_node(&cursor->ip->cache[1], 1435 cursor->node); 1436 } else { 1437 cursor->flags |= HAMMER_CURSOR_DISKEOF | 1438 HAMMER_CURSOR_ATEDISK; 1439 } 1440 } 1441 } 1442 1443 next_memory: 1444 /* 1445 * Get the next in-memory record. 1446 * 1447 * hammer_rec_scan_cmp: Is the record still in our general range, 1448 * (non-inclusive of snapshot exclusions)? 1449 * hammer_rec_scan_callback: Is the record in our snapshot? 1450 */ 1451 if (cursor->flags & HAMMER_CURSOR_ATEMEM) { 1452 if ((cursor->flags & HAMMER_CURSOR_MEMEOF) == 0) { 1453 save = cursor->iprec; 1454 cursor->iprec = NULL; 1455 rec = save ? hammer_rec_rb_tree_RB_NEXT(save) : NULL; 1456 while (rec) { 1457 if (hammer_rec_scan_cmp(rec, cursor) != 0) 1458 break; 1459 if (hammer_rec_scan_callback(rec, cursor) != 0) 1460 break; 1461 rec = hammer_rec_rb_tree_RB_NEXT(rec); 1462 } 1463 if (save) 1464 hammer_rel_mem_record(save); 1465 if (cursor->iprec) { 1466 KKASSERT(cursor->iprec == rec); 1467 cursor->flags &= ~HAMMER_CURSOR_ATEMEM; 1468 } else { 1469 cursor->flags |= HAMMER_CURSOR_MEMEOF; 1470 } 1471 } 1472 } 1473 1474 /* 1475 * The memory record may have become stale while being held in 1476 * cursor->iprec. We are interlocked against the backend on 1477 * with regards to B-Tree entries. 1478 */ 1479 if ((cursor->flags & HAMMER_CURSOR_ATEMEM) == 0) { 1480 if (hammer_ip_iterate_mem_good(cursor, cursor->iprec) == 0) { 1481 cursor->flags |= HAMMER_CURSOR_ATEMEM; 1482 goto next_memory; 1483 } 1484 } 1485 1486 /* 1487 * Extract either the disk or memory record depending on their 1488 * relative position. 1489 */ 1490 error = 0; 1491 switch(cursor->flags & (HAMMER_CURSOR_ATEDISK | HAMMER_CURSOR_ATEMEM)) { 1492 case 0: 1493 /* 1494 * Both entries valid. Compare the entries and nominally 1495 * return the first one in the sort order. Numerous cases 1496 * require special attention, however. 1497 */ 1498 elm = &cursor->node->ondisk->elms[cursor->index]; 1499 r = hammer_btree_cmp(&elm->base, &cursor->iprec->leaf.base); 1500 1501 /* 1502 * If the two entries differ only by their key (-2/2) or 1503 * create_tid (-1/1), and are DATA records, we may have a 1504 * nominal match. We have to calculate the base file 1505 * offset of the data. 1506 */ 1507 if (r <= 2 && r >= -2 && r != 0 && 1508 cursor->ip->ino_data.obj_type == HAMMER_OBJTYPE_REGFILE && 1509 cursor->iprec->type == HAMMER_MEM_RECORD_DATA) { 1510 int64_t base1 = elm->leaf.base.key - elm->leaf.data_len; 1511 int64_t base2 = cursor->iprec->leaf.base.key - 1512 cursor->iprec->leaf.data_len; 1513 if (base1 == base2) 1514 r = 0; 1515 } 1516 1517 if (r < 0) { 1518 error = hammer_btree_extract(cursor, 1519 HAMMER_CURSOR_GET_LEAF); 1520 cursor->flags |= HAMMER_CURSOR_ATEDISK; 1521 break; 1522 } 1523 1524 /* 1525 * If the entries match exactly the memory entry is either 1526 * an on-disk directory entry deletion or a bulk data 1527 * overwrite. If it is a directory entry deletion we eat 1528 * both entries. 1529 * 1530 * For the bulk-data overwrite case it is possible to have 1531 * visibility into both, which simply means the syncer 1532 * hasn't gotten around to doing the delete+insert sequence 1533 * on the B-Tree. Use the memory entry and throw away the 1534 * on-disk entry. 1535 * 1536 * If the in-memory record is not either of these we 1537 * probably caught the syncer while it was syncing it to 1538 * the media. Since we hold a shared lock on the cursor, 1539 * the in-memory record had better be marked deleted at 1540 * this point. 1541 */ 1542 if (r == 0) { 1543 if (cursor->iprec->type == HAMMER_MEM_RECORD_DEL) { 1544 if ((cursor->flags & HAMMER_CURSOR_DELETE_VISIBILITY) == 0) { 1545 cursor->flags |= HAMMER_CURSOR_ATEDISK; 1546 cursor->flags |= HAMMER_CURSOR_ATEMEM; 1547 goto next_btree; 1548 } 1549 } else if (cursor->iprec->type == HAMMER_MEM_RECORD_DATA) { 1550 if ((cursor->flags & HAMMER_CURSOR_DELETE_VISIBILITY) == 0) { 1551 cursor->flags |= HAMMER_CURSOR_ATEDISK; 1552 } 1553 /* fall through to memory entry */ 1554 } else { 1555 panic("hammer_ip_next: duplicate mem/b-tree entry %p %d %08x", cursor->iprec, cursor->iprec->type, cursor->iprec->flags); 1556 cursor->flags |= HAMMER_CURSOR_ATEMEM; 1557 goto next_memory; 1558 } 1559 } 1560 /* fall through to the memory entry */ 1561 case HAMMER_CURSOR_ATEDISK: 1562 /* 1563 * Only the memory entry is valid. 1564 */ 1565 cursor->leaf = &cursor->iprec->leaf; 1566 cursor->flags |= HAMMER_CURSOR_ATEMEM; 1567 1568 /* 1569 * If the memory entry is an on-disk deletion we should have 1570 * also had found a B-Tree record. If the backend beat us 1571 * to it it would have interlocked the cursor and we should 1572 * have seen the in-memory record marked DELETED_FE. 1573 */ 1574 if (cursor->iprec->type == HAMMER_MEM_RECORD_DEL && 1575 (cursor->flags & HAMMER_CURSOR_DELETE_VISIBILITY) == 0) { 1576 panic("hammer_ip_next: del-on-disk with no b-tree entry iprec %p flags %08x", cursor->iprec, cursor->iprec->flags); 1577 } 1578 break; 1579 case HAMMER_CURSOR_ATEMEM: 1580 /* 1581 * Only the disk entry is valid 1582 */ 1583 error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_LEAF); 1584 cursor->flags |= HAMMER_CURSOR_ATEDISK; 1585 break; 1586 default: 1587 /* 1588 * Neither entry is valid 1589 * 1590 * XXX error not set properly 1591 */ 1592 cursor->leaf = NULL; 1593 error = ENOENT; 1594 break; 1595 } 1596 return(error); 1597 } 1598 1599 /* 1600 * Resolve the cursor->data pointer for the current cursor position in 1601 * a merged iteration. 1602 */ 1603 int 1604 hammer_ip_resolve_data(hammer_cursor_t cursor) 1605 { 1606 hammer_record_t record; 1607 int error; 1608 1609 if (hammer_cursor_inmem(cursor)) { 1610 /* 1611 * The data associated with an in-memory record is usually 1612 * kmalloced, but reserve-ahead data records will have an 1613 * on-disk reference. 1614 * 1615 * NOTE: Reserve-ahead data records must be handled in the 1616 * context of the related high level buffer cache buffer 1617 * to interlock against async writes. 1618 */ 1619 record = cursor->iprec; 1620 cursor->data = record->data; 1621 error = 0; 1622 if (cursor->data == NULL) { 1623 KKASSERT(record->leaf.base.rec_type == 1624 HAMMER_RECTYPE_DATA); 1625 cursor->data = hammer_bread_ext(cursor->trans->hmp, 1626 record->leaf.data_offset, 1627 record->leaf.data_len, 1628 &error, 1629 &cursor->data_buffer); 1630 } 1631 } else { 1632 cursor->leaf = &cursor->node->ondisk->elms[cursor->index].leaf; 1633 error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_DATA); 1634 } 1635 return(error); 1636 } 1637 1638 /* 1639 * Backend truncation / record replacement - delete records in range. 1640 * 1641 * Delete all records within the specified range for inode ip. In-memory 1642 * records still associated with the frontend are ignored. 1643 * 1644 * If truncating is non-zero in-memory records associated with the back-end 1645 * are ignored. If truncating is > 1 we can return EWOULDBLOCK. 1646 * 1647 * NOTES: 1648 * 1649 * * An unaligned range will cause new records to be added to cover 1650 * the edge cases. (XXX not implemented yet). 1651 * 1652 * * Replacement via reservations (see hammer_ip_sync_record_cursor()) 1653 * also do not deal with unaligned ranges. 1654 * 1655 * * ran_end is inclusive (e.g. 0,1023 instead of 0,1024). 1656 * 1657 * * Record keys for regular file data have to be special-cased since 1658 * they indicate the end of the range (key = base + bytes). 1659 * 1660 * * This function may be asked to delete ridiculously huge ranges, for 1661 * example if someone truncates or removes a 1TB regular file. We 1662 * must be very careful on restarts and we may have to stop w/ 1663 * EWOULDBLOCK to avoid blowing out the buffer cache. 1664 */ 1665 int 1666 hammer_ip_delete_range(hammer_cursor_t cursor, hammer_inode_t ip, 1667 int64_t ran_beg, int64_t ran_end, int truncating) 1668 { 1669 hammer_transaction_t trans = cursor->trans; 1670 hammer_btree_leaf_elm_t leaf; 1671 int error; 1672 int64_t off; 1673 int64_t tmp64; 1674 1675 #if 0 1676 kprintf("delete_range %p %016llx-%016llx\n", ip, ran_beg, ran_end); 1677 #endif 1678 1679 KKASSERT(trans->type == HAMMER_TRANS_FLS); 1680 retry: 1681 hammer_normalize_cursor(cursor); 1682 cursor->key_beg.localization = ip->obj_localization + 1683 HAMMER_LOCALIZE_MISC; 1684 cursor->key_beg.obj_id = ip->obj_id; 1685 cursor->key_beg.create_tid = 0; 1686 cursor->key_beg.delete_tid = 0; 1687 cursor->key_beg.obj_type = 0; 1688 1689 if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) { 1690 cursor->key_beg.key = ran_beg; 1691 cursor->key_beg.rec_type = HAMMER_RECTYPE_DB; 1692 } else { 1693 /* 1694 * The key in the B-Tree is (base+bytes), so the first possible 1695 * matching key is ran_beg + 1. 1696 */ 1697 cursor->key_beg.key = ran_beg + 1; 1698 cursor->key_beg.rec_type = HAMMER_RECTYPE_DATA; 1699 } 1700 1701 cursor->key_end = cursor->key_beg; 1702 if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) { 1703 cursor->key_end.key = ran_end; 1704 } else { 1705 tmp64 = ran_end + MAXPHYS + 1; /* work around GCC-4 bug */ 1706 if (tmp64 < ran_end) 1707 cursor->key_end.key = 0x7FFFFFFFFFFFFFFFLL; 1708 else 1709 cursor->key_end.key = ran_end + MAXPHYS + 1; 1710 } 1711 1712 cursor->asof = ip->obj_asof; 1713 cursor->flags &= ~HAMMER_CURSOR_INITMASK; 1714 cursor->flags |= HAMMER_CURSOR_ASOF; 1715 cursor->flags |= HAMMER_CURSOR_DELETE_VISIBILITY; 1716 cursor->flags |= HAMMER_CURSOR_BACKEND; 1717 cursor->flags |= HAMMER_CURSOR_END_INCLUSIVE; 1718 1719 error = hammer_ip_first(cursor); 1720 1721 /* 1722 * Iterate through matching records and mark them as deleted. 1723 */ 1724 while (error == 0) { 1725 leaf = cursor->leaf; 1726 1727 KKASSERT(leaf->base.delete_tid == 0); 1728 KKASSERT(leaf->base.obj_id == ip->obj_id); 1729 1730 /* 1731 * There may be overlap cases for regular file data. Also 1732 * remember the key for a regular file record is (base + len), 1733 * NOT (base). 1734 * 1735 * Note that do to duplicates (mem & media) allowed by 1736 * DELETE_VISIBILITY, off can wind up less then ran_beg. 1737 */ 1738 if (leaf->base.rec_type == HAMMER_RECTYPE_DATA) { 1739 off = leaf->base.key - leaf->data_len; 1740 /* 1741 * Check the left edge case. We currently do not 1742 * split existing records. 1743 */ 1744 if (off < ran_beg && leaf->base.key > ran_beg) { 1745 panic("hammer left edge case %016llx %d\n", 1746 leaf->base.key, leaf->data_len); 1747 } 1748 1749 /* 1750 * Check the right edge case. Note that the 1751 * record can be completely out of bounds, which 1752 * terminates the search. 1753 * 1754 * base->key is exclusive of the right edge while 1755 * ran_end is inclusive of the right edge. The 1756 * (key - data_len) left boundary is inclusive. 1757 * 1758 * XXX theory-check this test at some point, are 1759 * we missing a + 1 somewhere? Note that ran_end 1760 * could overflow. 1761 */ 1762 if (leaf->base.key - 1 > ran_end) { 1763 if (leaf->base.key - leaf->data_len > ran_end) 1764 break; 1765 panic("hammer right edge case\n"); 1766 } 1767 } else { 1768 off = leaf->base.key; 1769 } 1770 1771 /* 1772 * Delete the record. When truncating we do not delete 1773 * in-memory (data) records because they represent data 1774 * written after the truncation. 1775 * 1776 * This will also physically destroy the B-Tree entry and 1777 * data if the retention policy dictates. The function 1778 * will set HAMMER_CURSOR_RETEST to cause hammer_ip_next() 1779 * to retest the new 'current' element. 1780 */ 1781 if (truncating == 0 || hammer_cursor_ondisk(cursor)) { 1782 error = hammer_ip_delete_record(cursor, ip, trans->tid); 1783 /* 1784 * If we have built up too many meta-buffers we risk 1785 * deadlocking the kernel and must stop. This can 1786 * occur when deleting ridiculously huge files. 1787 * sync_trunc_off is updated so the next cycle does 1788 * not re-iterate records we have already deleted. 1789 * 1790 * This is only done with formal truncations. 1791 */ 1792 if (truncating > 1 && error == 0 && 1793 hammer_flusher_meta_limit(ip->hmp)) { 1794 ip->sync_trunc_off = off; 1795 error = EWOULDBLOCK; 1796 } 1797 } 1798 if (error) 1799 break; 1800 ran_beg = off; /* for restart */ 1801 error = hammer_ip_next(cursor); 1802 } 1803 if (cursor->node) 1804 hammer_cache_node(&ip->cache[1], cursor->node); 1805 1806 if (error == EDEADLK) { 1807 hammer_done_cursor(cursor); 1808 error = hammer_init_cursor(trans, cursor, &ip->cache[1], ip); 1809 if (error == 0) 1810 goto retry; 1811 } 1812 if (error == ENOENT) 1813 error = 0; 1814 return(error); 1815 } 1816 1817 /* 1818 * This backend function deletes the specified record on-disk, similar to 1819 * delete_range but for a specific record. Unlike the exact deletions 1820 * used when deleting a directory entry this function uses an ASOF search 1821 * like delete_range. 1822 * 1823 * This function may be called with ip->obj_asof set for a slave snapshot, 1824 * so don't use it. We always delete non-historical records only. 1825 */ 1826 static int 1827 hammer_delete_general(hammer_cursor_t cursor, hammer_inode_t ip, 1828 hammer_btree_leaf_elm_t leaf) 1829 { 1830 hammer_transaction_t trans = cursor->trans; 1831 int error; 1832 1833 KKASSERT(trans->type == HAMMER_TRANS_FLS); 1834 retry: 1835 hammer_normalize_cursor(cursor); 1836 cursor->key_beg = leaf->base; 1837 cursor->asof = HAMMER_MAX_TID; 1838 cursor->flags &= ~HAMMER_CURSOR_INITMASK; 1839 cursor->flags |= HAMMER_CURSOR_ASOF; 1840 cursor->flags |= HAMMER_CURSOR_BACKEND; 1841 cursor->flags &= ~HAMMER_CURSOR_INSERT; 1842 1843 error = hammer_btree_lookup(cursor); 1844 if (error == 0) { 1845 error = hammer_ip_delete_record(cursor, ip, trans->tid); 1846 } 1847 if (error == EDEADLK) { 1848 hammer_done_cursor(cursor); 1849 error = hammer_init_cursor(trans, cursor, &ip->cache[1], ip); 1850 if (error == 0) 1851 goto retry; 1852 } 1853 return(error); 1854 } 1855 1856 /* 1857 * This function deletes remaining auxillary records when an inode is 1858 * being deleted. This function explicitly does not delete the 1859 * inode record, directory entry, data, or db records. Those must be 1860 * properly disposed of prior to this call. 1861 */ 1862 int 1863 hammer_ip_delete_clean(hammer_cursor_t cursor, hammer_inode_t ip, int *countp) 1864 { 1865 hammer_transaction_t trans = cursor->trans; 1866 hammer_btree_leaf_elm_t leaf; 1867 int error; 1868 1869 KKASSERT(trans->type == HAMMER_TRANS_FLS); 1870 retry: 1871 hammer_normalize_cursor(cursor); 1872 cursor->key_beg.localization = ip->obj_localization + 1873 HAMMER_LOCALIZE_MISC; 1874 cursor->key_beg.obj_id = ip->obj_id; 1875 cursor->key_beg.create_tid = 0; 1876 cursor->key_beg.delete_tid = 0; 1877 cursor->key_beg.obj_type = 0; 1878 cursor->key_beg.rec_type = HAMMER_RECTYPE_CLEAN_START; 1879 cursor->key_beg.key = HAMMER_MIN_KEY; 1880 1881 cursor->key_end = cursor->key_beg; 1882 cursor->key_end.rec_type = HAMMER_RECTYPE_MAX; 1883 cursor->key_end.key = HAMMER_MAX_KEY; 1884 1885 cursor->asof = ip->obj_asof; 1886 cursor->flags &= ~HAMMER_CURSOR_INITMASK; 1887 cursor->flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF; 1888 cursor->flags |= HAMMER_CURSOR_DELETE_VISIBILITY; 1889 cursor->flags |= HAMMER_CURSOR_BACKEND; 1890 1891 error = hammer_ip_first(cursor); 1892 1893 /* 1894 * Iterate through matching records and mark them as deleted. 1895 */ 1896 while (error == 0) { 1897 leaf = cursor->leaf; 1898 1899 KKASSERT(leaf->base.delete_tid == 0); 1900 1901 /* 1902 * Mark the record and B-Tree entry as deleted. This will 1903 * also physically delete the B-Tree entry, record, and 1904 * data if the retention policy dictates. The function 1905 * will set HAMMER_CURSOR_RETEST to cause hammer_ip_next() 1906 * to retest the new 'current' element. 1907 * 1908 * Directory entries (and delete-on-disk directory entries) 1909 * must be synced and cannot be deleted. 1910 */ 1911 error = hammer_ip_delete_record(cursor, ip, trans->tid); 1912 ++*countp; 1913 if (error) 1914 break; 1915 error = hammer_ip_next(cursor); 1916 } 1917 if (cursor->node) 1918 hammer_cache_node(&ip->cache[1], cursor->node); 1919 if (error == EDEADLK) { 1920 hammer_done_cursor(cursor); 1921 error = hammer_init_cursor(trans, cursor, &ip->cache[1], ip); 1922 if (error == 0) 1923 goto retry; 1924 } 1925 if (error == ENOENT) 1926 error = 0; 1927 return(error); 1928 } 1929 1930 /* 1931 * Delete the record at the current cursor. On success the cursor will 1932 * be positioned appropriately for an iteration but may no longer be at 1933 * a leaf node. 1934 * 1935 * This routine is only called from the backend. 1936 * 1937 * NOTE: This can return EDEADLK, requiring the caller to terminate the 1938 * cursor and retry. 1939 */ 1940 int 1941 hammer_ip_delete_record(hammer_cursor_t cursor, hammer_inode_t ip, 1942 hammer_tid_t tid) 1943 { 1944 hammer_record_t iprec; 1945 hammer_mount_t hmp; 1946 int error; 1947 1948 KKASSERT(cursor->flags & HAMMER_CURSOR_BACKEND); 1949 KKASSERT(tid != 0); 1950 hmp = cursor->node->hmp; 1951 1952 /* 1953 * In-memory (unsynchronized) records can simply be freed. This 1954 * only occurs in range iterations since all other records are 1955 * individually synchronized. Thus there should be no confusion with 1956 * the interlock. 1957 * 1958 * An in-memory record may be deleted before being committed to disk, 1959 * but could have been accessed in the mean time. The reservation 1960 * code will deal with the case. 1961 */ 1962 if (hammer_cursor_inmem(cursor)) { 1963 iprec = cursor->iprec; 1964 KKASSERT((iprec->flags & HAMMER_RECF_INTERLOCK_BE) ==0); 1965 iprec->flags |= HAMMER_RECF_DELETED_FE; 1966 iprec->flags |= HAMMER_RECF_DELETED_BE; 1967 return(0); 1968 } 1969 1970 /* 1971 * On-disk records are marked as deleted by updating their delete_tid. 1972 * This does not effect their position in the B-Tree (which is based 1973 * on their create_tid). 1974 * 1975 * Frontend B-Tree operations track inodes so we tell 1976 * hammer_delete_at_cursor() not to. 1977 */ 1978 error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_LEAF); 1979 1980 if (error == 0) { 1981 error = hammer_delete_at_cursor( 1982 cursor, 1983 HAMMER_DELETE_ADJUST | hammer_nohistory(ip), 1984 cursor->trans->tid, 1985 cursor->trans->time32, 1986 0, NULL); 1987 } 1988 return(error); 1989 } 1990 1991 /* 1992 * Delete the B-Tree element at the current cursor and do any necessary 1993 * mirror propagation. 1994 * 1995 * The cursor must be properly positioned for an iteration on return but 1996 * may be pointing at an internal element. 1997 * 1998 * An element can be un-deleted by passing a delete_tid of 0 with 1999 * HAMMER_DELETE_ADJUST. 2000 */ 2001 int 2002 hammer_delete_at_cursor(hammer_cursor_t cursor, int delete_flags, 2003 hammer_tid_t delete_tid, u_int32_t delete_ts, 2004 int track, int64_t *stat_bytes) 2005 { 2006 struct hammer_btree_leaf_elm save_leaf; 2007 hammer_transaction_t trans; 2008 hammer_btree_leaf_elm_t leaf; 2009 hammer_node_t node; 2010 hammer_btree_elm_t elm; 2011 hammer_off_t data_offset; 2012 int32_t data_len; 2013 u_int16_t rec_type; 2014 int error; 2015 int icount; 2016 int doprop; 2017 2018 error = hammer_cursor_upgrade(cursor); 2019 if (error) 2020 return(error); 2021 2022 trans = cursor->trans; 2023 node = cursor->node; 2024 elm = &node->ondisk->elms[cursor->index]; 2025 leaf = &elm->leaf; 2026 KKASSERT(elm->base.btype == HAMMER_BTREE_TYPE_RECORD); 2027 2028 hammer_sync_lock_sh(trans); 2029 doprop = 0; 2030 icount = 0; 2031 2032 /* 2033 * Adjust the delete_tid. Update the mirror_tid propagation field 2034 * as well. delete_tid can be 0 (undelete -- used by mirroring). 2035 */ 2036 if (delete_flags & HAMMER_DELETE_ADJUST) { 2037 if (elm->base.rec_type == HAMMER_RECTYPE_INODE) { 2038 if (elm->leaf.base.delete_tid == 0 && delete_tid) 2039 icount = -1; 2040 if (elm->leaf.base.delete_tid && delete_tid == 0) 2041 icount = 1; 2042 } 2043 2044 hammer_modify_node(trans, node, elm, sizeof(*elm)); 2045 elm->leaf.base.delete_tid = delete_tid; 2046 elm->leaf.delete_ts = delete_ts; 2047 hammer_modify_node_done(node); 2048 2049 if (elm->leaf.base.delete_tid > node->ondisk->mirror_tid) { 2050 hammer_modify_node_field(trans, node, mirror_tid); 2051 node->ondisk->mirror_tid = elm->leaf.base.delete_tid; 2052 hammer_modify_node_done(node); 2053 doprop = 1; 2054 if (hammer_debug_general & 0x0002) { 2055 kprintf("delete_at_cursor: propagate %016llx" 2056 " @%016llx\n", 2057 elm->leaf.base.delete_tid, 2058 node->node_offset); 2059 } 2060 } 2061 2062 /* 2063 * Adjust for the iteration. We have deleted the current 2064 * element and want to clear ATEDISK so the iteration does 2065 * not skip the element after, which now becomes the current 2066 * element. This element must be re-tested if doing an 2067 * iteration, which is handled by the RETEST flag. 2068 */ 2069 if ((cursor->flags & HAMMER_CURSOR_DISKEOF) == 0) { 2070 cursor->flags |= HAMMER_CURSOR_RETEST; 2071 cursor->flags &= ~HAMMER_CURSOR_ATEDISK; 2072 } 2073 2074 /* 2075 * An on-disk record cannot have the same delete_tid 2076 * as its create_tid. In a chain of record updates 2077 * this could result in a duplicate record. 2078 */ 2079 KKASSERT(elm->leaf.base.delete_tid != 2080 elm->leaf.base.create_tid); 2081 } 2082 2083 /* 2084 * Destroy the B-Tree element if asked (typically if a nohistory 2085 * file or mount, or when called by the pruning code). 2086 * 2087 * Adjust the ATEDISK flag to properly support iterations. 2088 */ 2089 if (delete_flags & HAMMER_DELETE_DESTROY) { 2090 data_offset = elm->leaf.data_offset; 2091 data_len = elm->leaf.data_len; 2092 rec_type = elm->leaf.base.rec_type; 2093 if (doprop) { 2094 save_leaf = elm->leaf; 2095 leaf = &save_leaf; 2096 } 2097 if (elm->base.rec_type == HAMMER_RECTYPE_INODE && 2098 elm->leaf.base.delete_tid == 0) { 2099 icount = -1; 2100 } 2101 2102 error = hammer_btree_delete(cursor); 2103 if (error == 0) { 2104 /* 2105 * The deletion moves the next element (if any) to 2106 * the current element position. We must clear 2107 * ATEDISK so this element is not skipped and we 2108 * must set RETEST to force any iteration to re-test 2109 * the element. 2110 */ 2111 if ((cursor->flags & HAMMER_CURSOR_DISKEOF) == 0) { 2112 cursor->flags |= HAMMER_CURSOR_RETEST; 2113 cursor->flags &= ~HAMMER_CURSOR_ATEDISK; 2114 } 2115 } 2116 if (error == 0) { 2117 switch(data_offset & HAMMER_OFF_ZONE_MASK) { 2118 case HAMMER_ZONE_LARGE_DATA: 2119 case HAMMER_ZONE_SMALL_DATA: 2120 case HAMMER_ZONE_META: 2121 hammer_blockmap_free(trans, 2122 data_offset, data_len); 2123 break; 2124 default: 2125 break; 2126 } 2127 } 2128 } 2129 2130 /* 2131 * Track inode count and next_tid. This is used by the mirroring 2132 * and PFS code. icount can be negative, zero, or positive. 2133 */ 2134 if (error == 0 && track) { 2135 if (icount) { 2136 hammer_modify_volume_field(trans, trans->rootvol, 2137 vol0_stat_inodes); 2138 trans->rootvol->ondisk->vol0_stat_inodes += icount; 2139 hammer_modify_volume_done(trans->rootvol); 2140 } 2141 if (trans->rootvol->ondisk->vol0_next_tid < delete_tid) { 2142 hammer_modify_volume(trans, trans->rootvol, NULL, 0); 2143 trans->rootvol->ondisk->vol0_next_tid = delete_tid; 2144 hammer_modify_volume_done(trans->rootvol); 2145 } 2146 } 2147 2148 /* 2149 * mirror_tid propagation occurs if the node's mirror_tid had to be 2150 * updated while adjusting the delete_tid. 2151 * 2152 * This occurs when deleting even in nohistory mode, but does not 2153 * occur when pruning an already-deleted node. 2154 * 2155 * cursor->ip is NULL when called from the pruning, mirroring, 2156 * and pfs code. If non-NULL propagation will be conditionalized 2157 * on whether the PFS is in no-history mode or not. 2158 */ 2159 if (doprop) { 2160 if (cursor->ip) 2161 hammer_btree_do_propagation(cursor, cursor->ip->pfsm, leaf); 2162 else 2163 hammer_btree_do_propagation(cursor, NULL, leaf); 2164 } 2165 hammer_sync_unlock(trans); 2166 return (error); 2167 } 2168 2169 /* 2170 * Determine whether we can remove a directory. This routine checks whether 2171 * a directory is empty or not and enforces flush connectivity. 2172 * 2173 * Flush connectivity requires that we block if the target directory is 2174 * currently flushing, otherwise it may not end up in the same flush group. 2175 * 2176 * Returns 0 on success, ENOTEMPTY or EDEADLK (or other errors) on failure. 2177 */ 2178 int 2179 hammer_ip_check_directory_empty(hammer_transaction_t trans, hammer_inode_t ip) 2180 { 2181 struct hammer_cursor cursor; 2182 int error; 2183 2184 /* 2185 * Check directory empty 2186 */ 2187 hammer_init_cursor(trans, &cursor, &ip->cache[1], ip); 2188 2189 cursor.key_beg.localization = ip->obj_localization + 2190 HAMMER_LOCALIZE_MISC; 2191 cursor.key_beg.obj_id = ip->obj_id; 2192 cursor.key_beg.create_tid = 0; 2193 cursor.key_beg.delete_tid = 0; 2194 cursor.key_beg.obj_type = 0; 2195 cursor.key_beg.rec_type = HAMMER_RECTYPE_INODE + 1; 2196 cursor.key_beg.key = HAMMER_MIN_KEY; 2197 2198 cursor.key_end = cursor.key_beg; 2199 cursor.key_end.rec_type = 0xFFFF; 2200 cursor.key_end.key = HAMMER_MAX_KEY; 2201 2202 cursor.asof = ip->obj_asof; 2203 cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF; 2204 2205 error = hammer_ip_first(&cursor); 2206 if (error == ENOENT) 2207 error = 0; 2208 else if (error == 0) 2209 error = ENOTEMPTY; 2210 hammer_done_cursor(&cursor); 2211 return(error); 2212 } 2213 2214