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. It could also be NULL indicating that the directory 707 * entry being removed has no related inode. 708 * 709 * This function can return EDEADLK requiring the caller to terminate 710 * the cursor, any locks, wait on the returned record, and retry. 711 */ 712 int 713 hammer_ip_del_directory(struct hammer_transaction *trans, 714 hammer_cursor_t cursor, struct hammer_inode *dip, 715 struct hammer_inode *ip) 716 { 717 hammer_record_t record; 718 int error; 719 720 if (hammer_cursor_inmem(cursor)) { 721 /* 722 * In-memory (unsynchronized) records can simply be freed. 723 * Even though the HAMMER_RECF_DELETED_FE flag is ignored 724 * by the backend, we must still avoid races against the 725 * backend potentially syncing the record to the media. 726 * 727 * We cannot call hammer_ip_delete_record(), that routine may 728 * only be called from the backend. 729 */ 730 record = cursor->iprec; 731 if (record->flags & HAMMER_RECF_INTERLOCK_BE) { 732 KKASSERT(cursor->deadlk_rec == NULL); 733 hammer_ref(&record->lock); 734 cursor->deadlk_rec = record; 735 error = EDEADLK; 736 } else { 737 KKASSERT(record->type == HAMMER_MEM_RECORD_ADD); 738 record->flags |= HAMMER_RECF_DELETED_FE; 739 error = 0; 740 } 741 } else { 742 /* 743 * If the record is on-disk we have to queue the deletion by 744 * the record's key. This also causes lookups to skip the 745 * record. 746 */ 747 KKASSERT(dip->flags & 748 (HAMMER_INODE_ONDISK | HAMMER_INODE_DONDISK)); 749 record = hammer_alloc_mem_record(dip, 0); 750 record->type = HAMMER_MEM_RECORD_DEL; 751 record->leaf.base = cursor->leaf->base; 752 753 /* 754 * ip may be NULL, indicating the deletion of a directory 755 * entry which has no related inode. 756 */ 757 record->target_ip = ip; 758 if (ip) { 759 record->flush_state = HAMMER_FST_SETUP; 760 TAILQ_INSERT_TAIL(&ip->target_list, record, 761 target_entry); 762 } else { 763 record->flush_state = HAMMER_FST_IDLE; 764 } 765 766 /* 767 * The inode now has a dependancy and must be taken out of 768 * the idle state. An inode not in an idle state is given 769 * an extra reference. 770 * 771 * When transitioning to a SETUP state flag for an automatic 772 * reflush when the dependancies are disposed of if someone 773 * is waiting on the inode. 774 */ 775 if (ip && ip->flush_state == HAMMER_FST_IDLE) { 776 hammer_ref(&ip->lock); 777 ip->flush_state = HAMMER_FST_SETUP; 778 if (ip->flags & HAMMER_INODE_FLUSHW) 779 ip->flags |= HAMMER_INODE_REFLUSH; 780 } 781 782 error = hammer_mem_add(record); 783 } 784 785 /* 786 * One less link. The file may still be open in the OS even after 787 * all links have gone away. 788 * 789 * We have to terminate the cursor before syncing the inode to 790 * avoid deadlocking against ourselves. XXX this may no longer 791 * be true. 792 * 793 * If nlinks drops to zero and the vnode is inactive (or there is 794 * no vnode), call hammer_inode_unloadable_check() to zonk the 795 * inode. If we don't do this here the inode will not be destroyed 796 * on-media until we unmount. 797 */ 798 if (error == 0) { 799 if (ip) 800 --ip->ino_data.nlinks; /* do before we might block */ 801 dip->ino_data.mtime = trans->time; 802 hammer_modify_inode(dip, HAMMER_INODE_MTIME); 803 if (ip) { 804 hammer_modify_inode(ip, HAMMER_INODE_DDIRTY); 805 if (ip->ino_data.nlinks == 0 && 806 (ip->vp == NULL || (ip->vp->v_flag & VINACTIVE))) { 807 hammer_done_cursor(cursor); 808 hammer_inode_unloadable_check(ip, 1); 809 hammer_flush_inode(ip, 0); 810 } 811 } 812 813 } 814 return(error); 815 } 816 817 /* 818 * Add a record to an inode. 819 * 820 * The caller must allocate the record with hammer_alloc_mem_record(ip) and 821 * initialize the following additional fields: 822 * 823 * The related inode should be share-locked by the caller. The caller is 824 * on the frontend. 825 * 826 * record->rec.entry.base.base.key 827 * record->rec.entry.base.base.rec_type 828 * record->rec.entry.base.base.data_len 829 * record->data (a copy will be kmalloc'd if it cannot be embedded) 830 */ 831 int 832 hammer_ip_add_record(struct hammer_transaction *trans, hammer_record_t record) 833 { 834 hammer_inode_t ip = record->ip; 835 int error; 836 837 KKASSERT(record->leaf.base.localization != 0); 838 record->leaf.base.obj_id = ip->obj_id; 839 record->leaf.base.obj_type = ip->ino_leaf.base.obj_type; 840 error = hammer_mem_add(record); 841 return(error); 842 } 843 844 /* 845 * Locate a bulk record in-memory. Bulk records allow disk space to be 846 * reserved so the front-end can flush large data writes without having 847 * to queue the BIO to the flusher. Only the related record gets queued 848 * to the flusher. 849 */ 850 851 static hammer_record_t 852 hammer_ip_get_bulk(hammer_inode_t ip, off_t file_offset, int bytes) 853 { 854 struct hammer_bulk_info info; 855 856 bzero(&info, sizeof(info)); 857 info.leaf.base.obj_id = ip->obj_id; 858 info.leaf.base.key = file_offset + bytes; 859 info.leaf.base.create_tid = 0; 860 info.leaf.base.delete_tid = 0; 861 info.leaf.base.rec_type = HAMMER_RECTYPE_DATA; 862 info.leaf.base.obj_type = 0; /* unused */ 863 info.leaf.base.btype = HAMMER_BTREE_TYPE_RECORD; /* unused */ 864 info.leaf.base.localization = ip->obj_localization + /* unused */ 865 HAMMER_LOCALIZE_MISC; 866 info.leaf.data_len = bytes; 867 868 hammer_rec_rb_tree_RB_SCAN(&ip->rec_tree, hammer_rec_overlap_cmp, 869 hammer_bulk_scan_callback, &info); 870 871 return(info.record); /* may be NULL */ 872 } 873 874 /* 875 * Take records vetted by overlap_cmp. The first non-deleted record 876 * (if any) stops the scan. 877 */ 878 static int 879 hammer_bulk_scan_callback(hammer_record_t record, void *data) 880 { 881 struct hammer_bulk_info *info = data; 882 883 if (record->flags & HAMMER_RECF_DELETED_FE) 884 return(0); 885 hammer_ref(&record->lock); 886 info->record = record; 887 return(-1); /* stop scan */ 888 } 889 890 /* 891 * Reserve blockmap space placemarked with an in-memory record. 892 * 893 * This routine is called by the frontend in order to be able to directly 894 * flush a buffer cache buffer. The frontend has locked the related buffer 895 * cache buffers and we should be able to manipulate any overlapping 896 * in-memory records. 897 * 898 * The caller is responsible for adding the returned record. 899 */ 900 hammer_record_t 901 hammer_ip_add_bulk(hammer_inode_t ip, off_t file_offset, void *data, int bytes, 902 int *errorp) 903 { 904 hammer_record_t record; 905 hammer_record_t conflict; 906 int zone; 907 908 /* 909 * Deal with conflicting in-memory records. We cannot have multiple 910 * in-memory records for the same base offset without seriously 911 * confusing the backend, including but not limited to the backend 912 * issuing delete-create-delete or create-delete-create sequences 913 * and asserting on the delete_tid being the same as the create_tid. 914 * 915 * If we encounter a record with the backend interlock set we cannot 916 * immediately delete it without confusing the backend. 917 */ 918 while ((conflict = hammer_ip_get_bulk(ip, file_offset, bytes)) !=NULL) { 919 if (conflict->flags & HAMMER_RECF_INTERLOCK_BE) { 920 conflict->flags |= HAMMER_RECF_WANTED; 921 tsleep(conflict, 0, "hmrrc3", 0); 922 } else { 923 conflict->flags |= HAMMER_RECF_DELETED_FE; 924 } 925 hammer_rel_mem_record(conflict); 926 } 927 928 /* 929 * Create a record to cover the direct write. This is called with 930 * the related BIO locked so there should be no possible conflict. 931 * 932 * The backend is responsible for finalizing the space reserved in 933 * this record. 934 * 935 * XXX bytes not aligned, depend on the reservation code to 936 * align the reservation. 937 */ 938 record = hammer_alloc_mem_record(ip, 0); 939 zone = (bytes >= HAMMER_BUFSIZE) ? HAMMER_ZONE_LARGE_DATA_INDEX : 940 HAMMER_ZONE_SMALL_DATA_INDEX; 941 record->resv = hammer_blockmap_reserve(ip->hmp, zone, bytes, 942 &record->leaf.data_offset, 943 errorp); 944 if (record->resv == NULL) { 945 kprintf("hammer_ip_add_bulk: reservation failed\n"); 946 hammer_rel_mem_record(record); 947 return(NULL); 948 } 949 record->type = HAMMER_MEM_RECORD_DATA; 950 record->leaf.base.rec_type = HAMMER_RECTYPE_DATA; 951 record->leaf.base.obj_type = ip->ino_leaf.base.obj_type; 952 record->leaf.base.obj_id = ip->obj_id; 953 record->leaf.base.key = file_offset + bytes; 954 record->leaf.base.localization = ip->obj_localization + 955 HAMMER_LOCALIZE_MISC; 956 record->leaf.data_len = bytes; 957 hammer_crc_set_leaf(data, &record->leaf); 958 KKASSERT(*errorp == 0); 959 return(record); 960 } 961 962 /* 963 * Frontend truncation code. Scan in-memory records only. On-disk records 964 * and records in a flushing state are handled by the backend. The vnops 965 * setattr code will handle the block containing the truncation point. 966 * 967 * Partial blocks are not deleted. 968 */ 969 int 970 hammer_ip_frontend_trunc(struct hammer_inode *ip, off_t file_size) 971 { 972 struct rec_trunc_info info; 973 974 switch(ip->ino_data.obj_type) { 975 case HAMMER_OBJTYPE_REGFILE: 976 info.rec_type = HAMMER_RECTYPE_DATA; 977 break; 978 case HAMMER_OBJTYPE_DBFILE: 979 info.rec_type = HAMMER_RECTYPE_DB; 980 break; 981 default: 982 return(EINVAL); 983 } 984 info.trunc_off = file_size; 985 hammer_rec_rb_tree_RB_SCAN(&ip->rec_tree, hammer_rec_trunc_cmp, 986 hammer_frontend_trunc_callback, &info); 987 return(0); 988 } 989 990 static int 991 hammer_frontend_trunc_callback(hammer_record_t record, void *data __unused) 992 { 993 if (record->flags & HAMMER_RECF_DELETED_FE) 994 return(0); 995 if (record->flush_state == HAMMER_FST_FLUSH) 996 return(0); 997 KKASSERT((record->flags & HAMMER_RECF_INTERLOCK_BE) == 0); 998 hammer_ref(&record->lock); 999 record->flags |= HAMMER_RECF_DELETED_FE; 1000 hammer_rel_mem_record(record); 1001 return(0); 1002 } 1003 1004 /* 1005 * Return 1 if the caller must check for and delete existing records 1006 * before writing out a new data record. 1007 * 1008 * Return 0 if the caller can just insert the record into the B-Tree without 1009 * checking. 1010 */ 1011 static int 1012 hammer_record_needs_overwrite_delete(hammer_record_t record) 1013 { 1014 hammer_inode_t ip = record->ip; 1015 int64_t file_offset; 1016 int r; 1017 1018 if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) 1019 file_offset = record->leaf.base.key; 1020 else 1021 file_offset = record->leaf.base.key - record->leaf.data_len; 1022 r = (file_offset < ip->save_trunc_off); 1023 if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) { 1024 if (ip->save_trunc_off <= record->leaf.base.key) 1025 ip->save_trunc_off = record->leaf.base.key + 1; 1026 } else { 1027 if (ip->save_trunc_off < record->leaf.base.key) 1028 ip->save_trunc_off = record->leaf.base.key; 1029 } 1030 return(r); 1031 } 1032 1033 /* 1034 * Backend code. Sync a record to the media. 1035 */ 1036 int 1037 hammer_ip_sync_record_cursor(hammer_cursor_t cursor, hammer_record_t record) 1038 { 1039 hammer_transaction_t trans = cursor->trans; 1040 int64_t file_offset; 1041 int bytes; 1042 void *bdata; 1043 int error; 1044 int doprop; 1045 1046 KKASSERT(record->flush_state == HAMMER_FST_FLUSH); 1047 KKASSERT(record->flags & HAMMER_RECF_INTERLOCK_BE); 1048 KKASSERT(record->leaf.base.localization != 0); 1049 1050 /* 1051 * Any direct-write related to the record must complete before we 1052 * can sync the record to the on-disk media. 1053 */ 1054 if (record->flags & (HAMMER_RECF_DIRECT_IO | HAMMER_RECF_DIRECT_INVAL)) 1055 hammer_io_direct_wait(record); 1056 1057 /* 1058 * If this is a bulk-data record placemarker there may be an existing 1059 * record on-disk, indicating a data overwrite. If there is the 1060 * on-disk record must be deleted before we can insert our new record. 1061 * 1062 * We've synthesized this record and do not know what the create_tid 1063 * on-disk is, nor how much data it represents. 1064 * 1065 * Keep in mind that (key) for data records is (base_offset + len), 1066 * not (base_offset). Also, we only want to get rid of on-disk 1067 * records since we are trying to sync our in-memory record, call 1068 * hammer_ip_delete_range() with truncating set to 1 to make sure 1069 * it skips in-memory records. 1070 * 1071 * It is ok for the lookup to return ENOENT. 1072 * 1073 * NOTE OPTIMIZATION: sync_trunc_off is used to determine if we have 1074 * to call hammer_ip_delete_range() or not. This also means we must 1075 * update sync_trunc_off() as we write. 1076 */ 1077 if (record->type == HAMMER_MEM_RECORD_DATA && 1078 hammer_record_needs_overwrite_delete(record)) { 1079 file_offset = record->leaf.base.key - record->leaf.data_len; 1080 bytes = (record->leaf.data_len + HAMMER_BUFMASK) & 1081 ~HAMMER_BUFMASK; 1082 KKASSERT((file_offset & HAMMER_BUFMASK) == 0); 1083 error = hammer_ip_delete_range( 1084 cursor, record->ip, 1085 file_offset, file_offset + bytes - 1, 1086 1); 1087 if (error && error != ENOENT) 1088 goto done; 1089 } 1090 1091 /* 1092 * If this is a general record there may be an on-disk version 1093 * that must be deleted before we can insert the new record. 1094 */ 1095 if (record->type == HAMMER_MEM_RECORD_GENERAL) { 1096 error = hammer_delete_general(cursor, record->ip, 1097 &record->leaf); 1098 if (error && error != ENOENT) 1099 goto done; 1100 } 1101 1102 /* 1103 * Setup the cursor. 1104 */ 1105 hammer_normalize_cursor(cursor); 1106 cursor->key_beg = record->leaf.base; 1107 cursor->flags &= ~HAMMER_CURSOR_INITMASK; 1108 cursor->flags |= HAMMER_CURSOR_BACKEND; 1109 cursor->flags &= ~HAMMER_CURSOR_INSERT; 1110 1111 /* 1112 * Records can wind up on-media before the inode itself is on-media. 1113 * Flag the case. 1114 */ 1115 record->ip->flags |= HAMMER_INODE_DONDISK; 1116 1117 /* 1118 * If we are deleting a directory entry an exact match must be 1119 * found on-disk. 1120 */ 1121 if (record->type == HAMMER_MEM_RECORD_DEL) { 1122 error = hammer_btree_lookup(cursor); 1123 if (error == 0) { 1124 KKASSERT(cursor->iprec == NULL); 1125 error = hammer_ip_delete_record(cursor, record->ip, 1126 trans->tid); 1127 if (error == 0) { 1128 record->flags |= HAMMER_RECF_DELETED_FE; 1129 record->flags |= HAMMER_RECF_DELETED_BE; 1130 record->flags |= HAMMER_RECF_COMMITTED; 1131 } 1132 } 1133 goto done; 1134 } 1135 1136 /* 1137 * We are inserting. 1138 * 1139 * Issue a lookup to position the cursor and locate the cluster. The 1140 * target key should not exist. If we are creating a directory entry 1141 * we may have to iterate the low 32 bits of the key to find an unused 1142 * key. 1143 */ 1144 hammer_sync_lock_sh(trans); 1145 cursor->flags |= HAMMER_CURSOR_INSERT; 1146 error = hammer_btree_lookup(cursor); 1147 if (hammer_debug_inode) 1148 kprintf("DOINSERT LOOKUP %d\n", error); 1149 if (error == 0) { 1150 kprintf("hammer_ip_sync_record: duplicate rec " 1151 "at (%016llx)\n", record->leaf.base.key); 1152 Debugger("duplicate record1"); 1153 error = EIO; 1154 } 1155 #if 0 1156 if (record->type == HAMMER_MEM_RECORD_DATA) 1157 kprintf("sync_record %016llx ---------------- %016llx %d\n", 1158 record->leaf.base.key - record->leaf.data_len, 1159 record->leaf.data_offset, error); 1160 #endif 1161 1162 if (error != ENOENT) 1163 goto done_unlock; 1164 1165 /* 1166 * Allocate the record and data. The result buffers will be 1167 * marked as being modified and further calls to 1168 * hammer_modify_buffer() will result in unneeded UNDO records. 1169 * 1170 * Support zero-fill records (data == NULL and data_len != 0) 1171 */ 1172 if (record->type == HAMMER_MEM_RECORD_DATA) { 1173 /* 1174 * The data portion of a bulk-data record has already been 1175 * committed to disk, we need only adjust the layer2 1176 * statistics in the same transaction as our B-Tree insert. 1177 */ 1178 KKASSERT(record->leaf.data_offset != 0); 1179 error = hammer_blockmap_finalize(trans, 1180 record->resv, 1181 record->leaf.data_offset, 1182 record->leaf.data_len); 1183 } else if (record->data && record->leaf.data_len) { 1184 /* 1185 * Wholely cached record, with data. Allocate the data. 1186 */ 1187 bdata = hammer_alloc_data(trans, record->leaf.data_len, 1188 record->leaf.base.rec_type, 1189 &record->leaf.data_offset, 1190 &cursor->data_buffer, &error); 1191 if (bdata == NULL) 1192 goto done_unlock; 1193 hammer_crc_set_leaf(record->data, &record->leaf); 1194 hammer_modify_buffer(trans, cursor->data_buffer, NULL, 0); 1195 bcopy(record->data, bdata, record->leaf.data_len); 1196 hammer_modify_buffer_done(cursor->data_buffer); 1197 } else { 1198 /* 1199 * Wholely cached record, without data. 1200 */ 1201 record->leaf.data_offset = 0; 1202 record->leaf.data_crc = 0; 1203 } 1204 1205 error = hammer_btree_insert(cursor, &record->leaf, &doprop); 1206 if (hammer_debug_inode && error) 1207 kprintf("BTREE INSERT error %d @ %016llx:%d key %016llx\n", error, cursor->node->node_offset, cursor->index, record->leaf.base.key); 1208 1209 /* 1210 * Our record is on-disk, normally mark the in-memory version as 1211 * deleted. If the record represented a directory deletion but 1212 * we had to sync a valid directory entry to disk we must convert 1213 * the record to a covering delete so the frontend does not have 1214 * visibility on the synced entry. 1215 */ 1216 if (error == 0) { 1217 if (doprop) { 1218 hammer_btree_do_propagation(cursor, 1219 record->ip->pfsm, 1220 &record->leaf); 1221 } 1222 if (record->flags & HAMMER_RECF_CONVERT_DELETE) { 1223 KKASSERT(record->type == HAMMER_MEM_RECORD_ADD); 1224 record->flags &= ~HAMMER_RECF_DELETED_FE; 1225 record->type = HAMMER_MEM_RECORD_DEL; 1226 KKASSERT(record->flush_state == HAMMER_FST_FLUSH); 1227 record->flags &= ~HAMMER_RECF_CONVERT_DELETE; 1228 /* hammer_flush_record_done takes care of the rest */ 1229 } else { 1230 record->flags |= HAMMER_RECF_DELETED_FE; 1231 record->flags |= HAMMER_RECF_DELETED_BE; 1232 } 1233 record->flags |= HAMMER_RECF_COMMITTED; 1234 } else { 1235 if (record->leaf.data_offset) { 1236 hammer_blockmap_free(trans, record->leaf.data_offset, 1237 record->leaf.data_len); 1238 } 1239 } 1240 done_unlock: 1241 hammer_sync_unlock(trans); 1242 done: 1243 return(error); 1244 } 1245 1246 /* 1247 * Add the record to the inode's rec_tree. The low 32 bits of a directory 1248 * entry's key is used to deal with hash collisions in the upper 32 bits. 1249 * A unique 64 bit key is generated in-memory and may be regenerated a 1250 * second time when the directory record is flushed to the on-disk B-Tree. 1251 * 1252 * A referenced record is passed to this function. This function 1253 * eats the reference. If an error occurs the record will be deleted. 1254 * 1255 * A copy of the temporary record->data pointer provided by the caller 1256 * will be made. 1257 */ 1258 int 1259 hammer_mem_add(hammer_record_t record) 1260 { 1261 hammer_mount_t hmp = record->ip->hmp; 1262 1263 /* 1264 * Make a private copy of record->data 1265 */ 1266 if (record->data) 1267 KKASSERT(record->flags & HAMMER_RECF_ALLOCDATA); 1268 1269 /* 1270 * Insert into the RB tree. A unique key should have already 1271 * been selected if this is a directory entry. 1272 */ 1273 if (RB_INSERT(hammer_rec_rb_tree, &record->ip->rec_tree, record)) { 1274 record->flags |= HAMMER_RECF_DELETED_FE; 1275 hammer_rel_mem_record(record); 1276 return (EEXIST); 1277 } 1278 ++hmp->count_newrecords; 1279 ++hmp->rsv_recs; 1280 ++record->ip->rsv_recs; 1281 record->ip->hmp->rsv_databytes += record->leaf.data_len; 1282 record->flags |= HAMMER_RECF_ONRBTREE; 1283 hammer_modify_inode(record->ip, HAMMER_INODE_XDIRTY); 1284 hammer_rel_mem_record(record); 1285 return(0); 1286 } 1287 1288 /************************************************************************ 1289 * HAMMER INODE MERGED-RECORD FUNCTIONS * 1290 ************************************************************************ 1291 * 1292 * These functions augment the B-Tree scanning functions in hammer_btree.c 1293 * by merging in-memory records with on-disk records. 1294 */ 1295 1296 /* 1297 * Locate a particular record either in-memory or on-disk. 1298 * 1299 * NOTE: This is basically a standalone routine, hammer_ip_next() may 1300 * NOT be called to iterate results. 1301 */ 1302 int 1303 hammer_ip_lookup(hammer_cursor_t cursor) 1304 { 1305 int error; 1306 1307 /* 1308 * If the element is in-memory return it without searching the 1309 * on-disk B-Tree 1310 */ 1311 KKASSERT(cursor->ip); 1312 error = hammer_mem_lookup(cursor); 1313 if (error == 0) { 1314 cursor->leaf = &cursor->iprec->leaf; 1315 return(error); 1316 } 1317 if (error != ENOENT) 1318 return(error); 1319 1320 /* 1321 * If the inode has on-disk components search the on-disk B-Tree. 1322 */ 1323 if ((cursor->ip->flags & (HAMMER_INODE_ONDISK|HAMMER_INODE_DONDISK)) == 0) 1324 return(error); 1325 error = hammer_btree_lookup(cursor); 1326 if (error == 0) 1327 error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_LEAF); 1328 return(error); 1329 } 1330 1331 /* 1332 * Locate the first record within the cursor's key_beg/key_end range, 1333 * restricted to a particular inode. 0 is returned on success, ENOENT 1334 * if no records matched the requested range, or some other error. 1335 * 1336 * When 0 is returned hammer_ip_next() may be used to iterate additional 1337 * records within the requested range. 1338 * 1339 * This function can return EDEADLK, requiring the caller to terminate 1340 * the cursor and try again. 1341 */ 1342 int 1343 hammer_ip_first(hammer_cursor_t cursor) 1344 { 1345 hammer_inode_t ip = cursor->ip; 1346 int error; 1347 1348 KKASSERT(ip != NULL); 1349 1350 /* 1351 * Clean up fields and setup for merged scan 1352 */ 1353 cursor->flags &= ~HAMMER_CURSOR_RETEST; 1354 cursor->flags |= HAMMER_CURSOR_ATEDISK | HAMMER_CURSOR_ATEMEM; 1355 cursor->flags |= HAMMER_CURSOR_DISKEOF | HAMMER_CURSOR_MEMEOF; 1356 if (cursor->iprec) { 1357 hammer_rel_mem_record(cursor->iprec); 1358 cursor->iprec = NULL; 1359 } 1360 1361 /* 1362 * Search the on-disk B-Tree. hammer_btree_lookup() only does an 1363 * exact lookup so if we get ENOENT we have to call the iterate 1364 * function to validate the first record after the begin key. 1365 * 1366 * The ATEDISK flag is used by hammer_btree_iterate to determine 1367 * whether it must index forwards or not. It is also used here 1368 * to select the next record from in-memory or on-disk. 1369 * 1370 * EDEADLK can only occur if the lookup hit an empty internal 1371 * element and couldn't delete it. Since this could only occur 1372 * in-range, we can just iterate from the failure point. 1373 */ 1374 if (ip->flags & (HAMMER_INODE_ONDISK|HAMMER_INODE_DONDISK)) { 1375 error = hammer_btree_lookup(cursor); 1376 if (error == ENOENT || error == EDEADLK) { 1377 cursor->flags &= ~HAMMER_CURSOR_ATEDISK; 1378 if (hammer_debug_general & 0x2000) 1379 kprintf("error %d node %p %016llx index %d\n", error, cursor->node, cursor->node->node_offset, cursor->index); 1380 error = hammer_btree_iterate(cursor); 1381 } 1382 if (error && error != ENOENT) 1383 return(error); 1384 if (error == 0) { 1385 cursor->flags &= ~HAMMER_CURSOR_DISKEOF; 1386 cursor->flags &= ~HAMMER_CURSOR_ATEDISK; 1387 } else { 1388 cursor->flags |= HAMMER_CURSOR_ATEDISK; 1389 } 1390 } 1391 1392 /* 1393 * Search the in-memory record list (Red-Black tree). Unlike the 1394 * B-Tree search, mem_first checks for records in the range. 1395 */ 1396 error = hammer_mem_first(cursor); 1397 if (error && error != ENOENT) 1398 return(error); 1399 if (error == 0) { 1400 cursor->flags &= ~HAMMER_CURSOR_MEMEOF; 1401 cursor->flags &= ~HAMMER_CURSOR_ATEMEM; 1402 if (hammer_ip_iterate_mem_good(cursor, cursor->iprec) == 0) 1403 cursor->flags |= HAMMER_CURSOR_ATEMEM; 1404 } 1405 1406 /* 1407 * This will return the first matching record. 1408 */ 1409 return(hammer_ip_next(cursor)); 1410 } 1411 1412 /* 1413 * Retrieve the next record in a merged iteration within the bounds of the 1414 * cursor. This call may be made multiple times after the cursor has been 1415 * initially searched with hammer_ip_first(). 1416 * 1417 * 0 is returned on success, ENOENT if no further records match the 1418 * requested range, or some other error code is returned. 1419 */ 1420 int 1421 hammer_ip_next(hammer_cursor_t cursor) 1422 { 1423 hammer_btree_elm_t elm; 1424 hammer_record_t rec, save; 1425 int error; 1426 int r; 1427 1428 next_btree: 1429 /* 1430 * Load the current on-disk and in-memory record. If we ate any 1431 * records we have to get the next one. 1432 * 1433 * If we deleted the last on-disk record we had scanned ATEDISK will 1434 * be clear and RETEST will be set, forcing a call to iterate. The 1435 * fact that ATEDISK is clear causes iterate to re-test the 'current' 1436 * element. If ATEDISK is set, iterate will skip the 'current' 1437 * element. 1438 * 1439 * Get the next on-disk record 1440 */ 1441 if (cursor->flags & (HAMMER_CURSOR_ATEDISK|HAMMER_CURSOR_RETEST)) { 1442 if ((cursor->flags & HAMMER_CURSOR_DISKEOF) == 0) { 1443 error = hammer_btree_iterate(cursor); 1444 cursor->flags &= ~HAMMER_CURSOR_RETEST; 1445 if (error == 0) { 1446 cursor->flags &= ~HAMMER_CURSOR_ATEDISK; 1447 hammer_cache_node(&cursor->ip->cache[1], 1448 cursor->node); 1449 } else { 1450 cursor->flags |= HAMMER_CURSOR_DISKEOF | 1451 HAMMER_CURSOR_ATEDISK; 1452 } 1453 } 1454 } 1455 1456 next_memory: 1457 /* 1458 * Get the next in-memory record. 1459 * 1460 * hammer_rec_scan_cmp: Is the record still in our general range, 1461 * (non-inclusive of snapshot exclusions)? 1462 * hammer_rec_scan_callback: Is the record in our snapshot? 1463 */ 1464 if (cursor->flags & HAMMER_CURSOR_ATEMEM) { 1465 if ((cursor->flags & HAMMER_CURSOR_MEMEOF) == 0) { 1466 save = cursor->iprec; 1467 cursor->iprec = NULL; 1468 rec = save ? hammer_rec_rb_tree_RB_NEXT(save) : NULL; 1469 while (rec) { 1470 if (hammer_rec_scan_cmp(rec, cursor) != 0) 1471 break; 1472 if (hammer_rec_scan_callback(rec, cursor) != 0) 1473 break; 1474 rec = hammer_rec_rb_tree_RB_NEXT(rec); 1475 } 1476 if (save) 1477 hammer_rel_mem_record(save); 1478 if (cursor->iprec) { 1479 KKASSERT(cursor->iprec == rec); 1480 cursor->flags &= ~HAMMER_CURSOR_ATEMEM; 1481 } else { 1482 cursor->flags |= HAMMER_CURSOR_MEMEOF; 1483 } 1484 } 1485 } 1486 1487 /* 1488 * The memory record may have become stale while being held in 1489 * cursor->iprec. We are interlocked against the backend on 1490 * with regards to B-Tree entries. 1491 */ 1492 if ((cursor->flags & HAMMER_CURSOR_ATEMEM) == 0) { 1493 if (hammer_ip_iterate_mem_good(cursor, cursor->iprec) == 0) { 1494 cursor->flags |= HAMMER_CURSOR_ATEMEM; 1495 goto next_memory; 1496 } 1497 } 1498 1499 /* 1500 * Extract either the disk or memory record depending on their 1501 * relative position. 1502 */ 1503 error = 0; 1504 switch(cursor->flags & (HAMMER_CURSOR_ATEDISK | HAMMER_CURSOR_ATEMEM)) { 1505 case 0: 1506 /* 1507 * Both entries valid. Compare the entries and nominally 1508 * return the first one in the sort order. Numerous cases 1509 * require special attention, however. 1510 */ 1511 elm = &cursor->node->ondisk->elms[cursor->index]; 1512 r = hammer_btree_cmp(&elm->base, &cursor->iprec->leaf.base); 1513 1514 /* 1515 * If the two entries differ only by their key (-2/2) or 1516 * create_tid (-1/1), and are DATA records, we may have a 1517 * nominal match. We have to calculate the base file 1518 * offset of the data. 1519 */ 1520 if (r <= 2 && r >= -2 && r != 0 && 1521 cursor->ip->ino_data.obj_type == HAMMER_OBJTYPE_REGFILE && 1522 cursor->iprec->type == HAMMER_MEM_RECORD_DATA) { 1523 int64_t base1 = elm->leaf.base.key - elm->leaf.data_len; 1524 int64_t base2 = cursor->iprec->leaf.base.key - 1525 cursor->iprec->leaf.data_len; 1526 if (base1 == base2) 1527 r = 0; 1528 } 1529 1530 if (r < 0) { 1531 error = hammer_btree_extract(cursor, 1532 HAMMER_CURSOR_GET_LEAF); 1533 cursor->flags |= HAMMER_CURSOR_ATEDISK; 1534 break; 1535 } 1536 1537 /* 1538 * If the entries match exactly the memory entry is either 1539 * an on-disk directory entry deletion or a bulk data 1540 * overwrite. If it is a directory entry deletion we eat 1541 * both entries. 1542 * 1543 * For the bulk-data overwrite case it is possible to have 1544 * visibility into both, which simply means the syncer 1545 * hasn't gotten around to doing the delete+insert sequence 1546 * on the B-Tree. Use the memory entry and throw away the 1547 * on-disk entry. 1548 * 1549 * If the in-memory record is not either of these we 1550 * probably caught the syncer while it was syncing it to 1551 * the media. Since we hold a shared lock on the cursor, 1552 * the in-memory record had better be marked deleted at 1553 * this point. 1554 */ 1555 if (r == 0) { 1556 if (cursor->iprec->type == HAMMER_MEM_RECORD_DEL) { 1557 if ((cursor->flags & HAMMER_CURSOR_DELETE_VISIBILITY) == 0) { 1558 cursor->flags |= HAMMER_CURSOR_ATEDISK; 1559 cursor->flags |= HAMMER_CURSOR_ATEMEM; 1560 goto next_btree; 1561 } 1562 } else if (cursor->iprec->type == HAMMER_MEM_RECORD_DATA) { 1563 if ((cursor->flags & HAMMER_CURSOR_DELETE_VISIBILITY) == 0) { 1564 cursor->flags |= HAMMER_CURSOR_ATEDISK; 1565 } 1566 /* fall through to memory entry */ 1567 } else { 1568 panic("hammer_ip_next: duplicate mem/b-tree entry %p %d %08x", cursor->iprec, cursor->iprec->type, cursor->iprec->flags); 1569 cursor->flags |= HAMMER_CURSOR_ATEMEM; 1570 goto next_memory; 1571 } 1572 } 1573 /* fall through to the memory entry */ 1574 case HAMMER_CURSOR_ATEDISK: 1575 /* 1576 * Only the memory entry is valid. 1577 */ 1578 cursor->leaf = &cursor->iprec->leaf; 1579 cursor->flags |= HAMMER_CURSOR_ATEMEM; 1580 1581 /* 1582 * If the memory entry is an on-disk deletion we should have 1583 * also had found a B-Tree record. If the backend beat us 1584 * to it it would have interlocked the cursor and we should 1585 * have seen the in-memory record marked DELETED_FE. 1586 */ 1587 if (cursor->iprec->type == HAMMER_MEM_RECORD_DEL && 1588 (cursor->flags & HAMMER_CURSOR_DELETE_VISIBILITY) == 0) { 1589 panic("hammer_ip_next: del-on-disk with no b-tree entry iprec %p flags %08x", cursor->iprec, cursor->iprec->flags); 1590 } 1591 break; 1592 case HAMMER_CURSOR_ATEMEM: 1593 /* 1594 * Only the disk entry is valid 1595 */ 1596 error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_LEAF); 1597 cursor->flags |= HAMMER_CURSOR_ATEDISK; 1598 break; 1599 default: 1600 /* 1601 * Neither entry is valid 1602 * 1603 * XXX error not set properly 1604 */ 1605 cursor->leaf = NULL; 1606 error = ENOENT; 1607 break; 1608 } 1609 return(error); 1610 } 1611 1612 /* 1613 * Resolve the cursor->data pointer for the current cursor position in 1614 * a merged iteration. 1615 */ 1616 int 1617 hammer_ip_resolve_data(hammer_cursor_t cursor) 1618 { 1619 hammer_record_t record; 1620 int error; 1621 1622 if (hammer_cursor_inmem(cursor)) { 1623 /* 1624 * The data associated with an in-memory record is usually 1625 * kmalloced, but reserve-ahead data records will have an 1626 * on-disk reference. 1627 * 1628 * NOTE: Reserve-ahead data records must be handled in the 1629 * context of the related high level buffer cache buffer 1630 * to interlock against async writes. 1631 */ 1632 record = cursor->iprec; 1633 cursor->data = record->data; 1634 error = 0; 1635 if (cursor->data == NULL) { 1636 KKASSERT(record->leaf.base.rec_type == 1637 HAMMER_RECTYPE_DATA); 1638 cursor->data = hammer_bread_ext(cursor->trans->hmp, 1639 record->leaf.data_offset, 1640 record->leaf.data_len, 1641 &error, 1642 &cursor->data_buffer); 1643 } 1644 } else { 1645 cursor->leaf = &cursor->node->ondisk->elms[cursor->index].leaf; 1646 error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_DATA); 1647 } 1648 return(error); 1649 } 1650 1651 /* 1652 * Backend truncation / record replacement - delete records in range. 1653 * 1654 * Delete all records within the specified range for inode ip. In-memory 1655 * records still associated with the frontend are ignored. 1656 * 1657 * If truncating is non-zero in-memory records associated with the back-end 1658 * are ignored. If truncating is > 1 we can return EWOULDBLOCK. 1659 * 1660 * NOTES: 1661 * 1662 * * An unaligned range will cause new records to be added to cover 1663 * the edge cases. (XXX not implemented yet). 1664 * 1665 * * Replacement via reservations (see hammer_ip_sync_record_cursor()) 1666 * also do not deal with unaligned ranges. 1667 * 1668 * * ran_end is inclusive (e.g. 0,1023 instead of 0,1024). 1669 * 1670 * * Record keys for regular file data have to be special-cased since 1671 * they indicate the end of the range (key = base + bytes). 1672 * 1673 * * This function may be asked to delete ridiculously huge ranges, for 1674 * example if someone truncates or removes a 1TB regular file. We 1675 * must be very careful on restarts and we may have to stop w/ 1676 * EWOULDBLOCK to avoid blowing out the buffer cache. 1677 */ 1678 int 1679 hammer_ip_delete_range(hammer_cursor_t cursor, hammer_inode_t ip, 1680 int64_t ran_beg, int64_t ran_end, int truncating) 1681 { 1682 hammer_transaction_t trans = cursor->trans; 1683 hammer_btree_leaf_elm_t leaf; 1684 int error; 1685 int64_t off; 1686 int64_t tmp64; 1687 1688 #if 0 1689 kprintf("delete_range %p %016llx-%016llx\n", ip, ran_beg, ran_end); 1690 #endif 1691 1692 KKASSERT(trans->type == HAMMER_TRANS_FLS); 1693 retry: 1694 hammer_normalize_cursor(cursor); 1695 cursor->key_beg.localization = ip->obj_localization + 1696 HAMMER_LOCALIZE_MISC; 1697 cursor->key_beg.obj_id = ip->obj_id; 1698 cursor->key_beg.create_tid = 0; 1699 cursor->key_beg.delete_tid = 0; 1700 cursor->key_beg.obj_type = 0; 1701 1702 if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) { 1703 cursor->key_beg.key = ran_beg; 1704 cursor->key_beg.rec_type = HAMMER_RECTYPE_DB; 1705 } else { 1706 /* 1707 * The key in the B-Tree is (base+bytes), so the first possible 1708 * matching key is ran_beg + 1. 1709 */ 1710 cursor->key_beg.key = ran_beg + 1; 1711 cursor->key_beg.rec_type = HAMMER_RECTYPE_DATA; 1712 } 1713 1714 cursor->key_end = cursor->key_beg; 1715 if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) { 1716 cursor->key_end.key = ran_end; 1717 } else { 1718 tmp64 = ran_end + MAXPHYS + 1; /* work around GCC-4 bug */ 1719 if (tmp64 < ran_end) 1720 cursor->key_end.key = 0x7FFFFFFFFFFFFFFFLL; 1721 else 1722 cursor->key_end.key = ran_end + MAXPHYS + 1; 1723 } 1724 1725 cursor->asof = ip->obj_asof; 1726 cursor->flags &= ~HAMMER_CURSOR_INITMASK; 1727 cursor->flags |= HAMMER_CURSOR_ASOF; 1728 cursor->flags |= HAMMER_CURSOR_DELETE_VISIBILITY; 1729 cursor->flags |= HAMMER_CURSOR_BACKEND; 1730 cursor->flags |= HAMMER_CURSOR_END_INCLUSIVE; 1731 1732 error = hammer_ip_first(cursor); 1733 1734 /* 1735 * Iterate through matching records and mark them as deleted. 1736 */ 1737 while (error == 0) { 1738 leaf = cursor->leaf; 1739 1740 KKASSERT(leaf->base.delete_tid == 0); 1741 KKASSERT(leaf->base.obj_id == ip->obj_id); 1742 1743 /* 1744 * There may be overlap cases for regular file data. Also 1745 * remember the key for a regular file record is (base + len), 1746 * NOT (base). 1747 * 1748 * Note that do to duplicates (mem & media) allowed by 1749 * DELETE_VISIBILITY, off can wind up less then ran_beg. 1750 */ 1751 if (leaf->base.rec_type == HAMMER_RECTYPE_DATA) { 1752 off = leaf->base.key - leaf->data_len; 1753 /* 1754 * Check the left edge case. We currently do not 1755 * split existing records. 1756 */ 1757 if (off < ran_beg && leaf->base.key > ran_beg) { 1758 panic("hammer left edge case %016llx %d\n", 1759 leaf->base.key, leaf->data_len); 1760 } 1761 1762 /* 1763 * Check the right edge case. Note that the 1764 * record can be completely out of bounds, which 1765 * terminates the search. 1766 * 1767 * base->key is exclusive of the right edge while 1768 * ran_end is inclusive of the right edge. The 1769 * (key - data_len) left boundary is inclusive. 1770 * 1771 * XXX theory-check this test at some point, are 1772 * we missing a + 1 somewhere? Note that ran_end 1773 * could overflow. 1774 */ 1775 if (leaf->base.key - 1 > ran_end) { 1776 if (leaf->base.key - leaf->data_len > ran_end) 1777 break; 1778 panic("hammer right edge case\n"); 1779 } 1780 } else { 1781 off = leaf->base.key; 1782 } 1783 1784 /* 1785 * Delete the record. When truncating we do not delete 1786 * in-memory (data) records because they represent data 1787 * written after the truncation. 1788 * 1789 * This will also physically destroy the B-Tree entry and 1790 * data if the retention policy dictates. The function 1791 * will set HAMMER_CURSOR_RETEST to cause hammer_ip_next() 1792 * to retest the new 'current' element. 1793 */ 1794 if (truncating == 0 || hammer_cursor_ondisk(cursor)) { 1795 error = hammer_ip_delete_record(cursor, ip, trans->tid); 1796 /* 1797 * If we have built up too many meta-buffers we risk 1798 * deadlocking the kernel and must stop. This can 1799 * occur when deleting ridiculously huge files. 1800 * sync_trunc_off is updated so the next cycle does 1801 * not re-iterate records we have already deleted. 1802 * 1803 * This is only done with formal truncations. 1804 */ 1805 if (truncating > 1 && error == 0 && 1806 hammer_flusher_meta_limit(ip->hmp)) { 1807 ip->sync_trunc_off = off; 1808 error = EWOULDBLOCK; 1809 } 1810 } 1811 if (error) 1812 break; 1813 ran_beg = off; /* for restart */ 1814 error = hammer_ip_next(cursor); 1815 } 1816 if (cursor->node) 1817 hammer_cache_node(&ip->cache[1], cursor->node); 1818 1819 if (error == EDEADLK) { 1820 hammer_done_cursor(cursor); 1821 error = hammer_init_cursor(trans, cursor, &ip->cache[1], ip); 1822 if (error == 0) 1823 goto retry; 1824 } 1825 if (error == ENOENT) 1826 error = 0; 1827 return(error); 1828 } 1829 1830 /* 1831 * This backend function deletes the specified record on-disk, similar to 1832 * delete_range but for a specific record. Unlike the exact deletions 1833 * used when deleting a directory entry this function uses an ASOF search 1834 * like delete_range. 1835 * 1836 * This function may be called with ip->obj_asof set for a slave snapshot, 1837 * so don't use it. We always delete non-historical records only. 1838 */ 1839 static int 1840 hammer_delete_general(hammer_cursor_t cursor, hammer_inode_t ip, 1841 hammer_btree_leaf_elm_t leaf) 1842 { 1843 hammer_transaction_t trans = cursor->trans; 1844 int error; 1845 1846 KKASSERT(trans->type == HAMMER_TRANS_FLS); 1847 retry: 1848 hammer_normalize_cursor(cursor); 1849 cursor->key_beg = leaf->base; 1850 cursor->asof = HAMMER_MAX_TID; 1851 cursor->flags &= ~HAMMER_CURSOR_INITMASK; 1852 cursor->flags |= HAMMER_CURSOR_ASOF; 1853 cursor->flags |= HAMMER_CURSOR_BACKEND; 1854 cursor->flags &= ~HAMMER_CURSOR_INSERT; 1855 1856 error = hammer_btree_lookup(cursor); 1857 if (error == 0) { 1858 error = hammer_ip_delete_record(cursor, ip, trans->tid); 1859 } 1860 if (error == EDEADLK) { 1861 hammer_done_cursor(cursor); 1862 error = hammer_init_cursor(trans, cursor, &ip->cache[1], ip); 1863 if (error == 0) 1864 goto retry; 1865 } 1866 return(error); 1867 } 1868 1869 /* 1870 * This function deletes remaining auxillary records when an inode is 1871 * being deleted. This function explicitly does not delete the 1872 * inode record, directory entry, data, or db records. Those must be 1873 * properly disposed of prior to this call. 1874 */ 1875 int 1876 hammer_ip_delete_clean(hammer_cursor_t cursor, hammer_inode_t ip, int *countp) 1877 { 1878 hammer_transaction_t trans = cursor->trans; 1879 hammer_btree_leaf_elm_t leaf; 1880 int error; 1881 1882 KKASSERT(trans->type == HAMMER_TRANS_FLS); 1883 retry: 1884 hammer_normalize_cursor(cursor); 1885 cursor->key_beg.localization = ip->obj_localization + 1886 HAMMER_LOCALIZE_MISC; 1887 cursor->key_beg.obj_id = ip->obj_id; 1888 cursor->key_beg.create_tid = 0; 1889 cursor->key_beg.delete_tid = 0; 1890 cursor->key_beg.obj_type = 0; 1891 cursor->key_beg.rec_type = HAMMER_RECTYPE_CLEAN_START; 1892 cursor->key_beg.key = HAMMER_MIN_KEY; 1893 1894 cursor->key_end = cursor->key_beg; 1895 cursor->key_end.rec_type = HAMMER_RECTYPE_MAX; 1896 cursor->key_end.key = HAMMER_MAX_KEY; 1897 1898 cursor->asof = ip->obj_asof; 1899 cursor->flags &= ~HAMMER_CURSOR_INITMASK; 1900 cursor->flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF; 1901 cursor->flags |= HAMMER_CURSOR_DELETE_VISIBILITY; 1902 cursor->flags |= HAMMER_CURSOR_BACKEND; 1903 1904 error = hammer_ip_first(cursor); 1905 1906 /* 1907 * Iterate through matching records and mark them as deleted. 1908 */ 1909 while (error == 0) { 1910 leaf = cursor->leaf; 1911 1912 KKASSERT(leaf->base.delete_tid == 0); 1913 1914 /* 1915 * Mark the record and B-Tree entry as deleted. This will 1916 * also physically delete the B-Tree entry, record, and 1917 * data if the retention policy dictates. The function 1918 * will set HAMMER_CURSOR_RETEST to cause hammer_ip_next() 1919 * to retest the new 'current' element. 1920 * 1921 * Directory entries (and delete-on-disk directory entries) 1922 * must be synced and cannot be deleted. 1923 */ 1924 error = hammer_ip_delete_record(cursor, ip, trans->tid); 1925 ++*countp; 1926 if (error) 1927 break; 1928 error = hammer_ip_next(cursor); 1929 } 1930 if (cursor->node) 1931 hammer_cache_node(&ip->cache[1], cursor->node); 1932 if (error == EDEADLK) { 1933 hammer_done_cursor(cursor); 1934 error = hammer_init_cursor(trans, cursor, &ip->cache[1], ip); 1935 if (error == 0) 1936 goto retry; 1937 } 1938 if (error == ENOENT) 1939 error = 0; 1940 return(error); 1941 } 1942 1943 /* 1944 * Delete the record at the current cursor. On success the cursor will 1945 * be positioned appropriately for an iteration but may no longer be at 1946 * a leaf node. 1947 * 1948 * This routine is only called from the backend. 1949 * 1950 * NOTE: This can return EDEADLK, requiring the caller to terminate the 1951 * cursor and retry. 1952 */ 1953 int 1954 hammer_ip_delete_record(hammer_cursor_t cursor, hammer_inode_t ip, 1955 hammer_tid_t tid) 1956 { 1957 hammer_record_t iprec; 1958 hammer_mount_t hmp; 1959 int error; 1960 1961 KKASSERT(cursor->flags & HAMMER_CURSOR_BACKEND); 1962 KKASSERT(tid != 0); 1963 hmp = cursor->node->hmp; 1964 1965 /* 1966 * In-memory (unsynchronized) records can simply be freed. This 1967 * only occurs in range iterations since all other records are 1968 * individually synchronized. Thus there should be no confusion with 1969 * the interlock. 1970 * 1971 * An in-memory record may be deleted before being committed to disk, 1972 * but could have been accessed in the mean time. The reservation 1973 * code will deal with the case. 1974 */ 1975 if (hammer_cursor_inmem(cursor)) { 1976 iprec = cursor->iprec; 1977 KKASSERT((iprec->flags & HAMMER_RECF_INTERLOCK_BE) ==0); 1978 iprec->flags |= HAMMER_RECF_DELETED_FE; 1979 iprec->flags |= HAMMER_RECF_DELETED_BE; 1980 return(0); 1981 } 1982 1983 /* 1984 * On-disk records are marked as deleted by updating their delete_tid. 1985 * This does not effect their position in the B-Tree (which is based 1986 * on their create_tid). 1987 * 1988 * Frontend B-Tree operations track inodes so we tell 1989 * hammer_delete_at_cursor() not to. 1990 */ 1991 error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_LEAF); 1992 1993 if (error == 0) { 1994 error = hammer_delete_at_cursor( 1995 cursor, 1996 HAMMER_DELETE_ADJUST | hammer_nohistory(ip), 1997 cursor->trans->tid, 1998 cursor->trans->time32, 1999 0, NULL); 2000 } 2001 return(error); 2002 } 2003 2004 /* 2005 * Delete the B-Tree element at the current cursor and do any necessary 2006 * mirror propagation. 2007 * 2008 * The cursor must be properly positioned for an iteration on return but 2009 * may be pointing at an internal element. 2010 * 2011 * An element can be un-deleted by passing a delete_tid of 0 with 2012 * HAMMER_DELETE_ADJUST. 2013 */ 2014 int 2015 hammer_delete_at_cursor(hammer_cursor_t cursor, int delete_flags, 2016 hammer_tid_t delete_tid, u_int32_t delete_ts, 2017 int track, int64_t *stat_bytes) 2018 { 2019 struct hammer_btree_leaf_elm save_leaf; 2020 hammer_transaction_t trans; 2021 hammer_btree_leaf_elm_t leaf; 2022 hammer_node_t node; 2023 hammer_btree_elm_t elm; 2024 hammer_off_t data_offset; 2025 int32_t data_len; 2026 u_int16_t rec_type; 2027 int error; 2028 int icount; 2029 int doprop; 2030 2031 error = hammer_cursor_upgrade(cursor); 2032 if (error) 2033 return(error); 2034 2035 trans = cursor->trans; 2036 node = cursor->node; 2037 elm = &node->ondisk->elms[cursor->index]; 2038 leaf = &elm->leaf; 2039 KKASSERT(elm->base.btype == HAMMER_BTREE_TYPE_RECORD); 2040 2041 hammer_sync_lock_sh(trans); 2042 doprop = 0; 2043 icount = 0; 2044 2045 /* 2046 * Adjust the delete_tid. Update the mirror_tid propagation field 2047 * as well. delete_tid can be 0 (undelete -- used by mirroring). 2048 */ 2049 if (delete_flags & HAMMER_DELETE_ADJUST) { 2050 if (elm->base.rec_type == HAMMER_RECTYPE_INODE) { 2051 if (elm->leaf.base.delete_tid == 0 && delete_tid) 2052 icount = -1; 2053 if (elm->leaf.base.delete_tid && delete_tid == 0) 2054 icount = 1; 2055 } 2056 2057 hammer_modify_node(trans, node, elm, sizeof(*elm)); 2058 elm->leaf.base.delete_tid = delete_tid; 2059 elm->leaf.delete_ts = delete_ts; 2060 hammer_modify_node_done(node); 2061 2062 if (elm->leaf.base.delete_tid > node->ondisk->mirror_tid) { 2063 hammer_modify_node_field(trans, node, mirror_tid); 2064 node->ondisk->mirror_tid = elm->leaf.base.delete_tid; 2065 hammer_modify_node_done(node); 2066 doprop = 1; 2067 if (hammer_debug_general & 0x0002) { 2068 kprintf("delete_at_cursor: propagate %016llx" 2069 " @%016llx\n", 2070 elm->leaf.base.delete_tid, 2071 node->node_offset); 2072 } 2073 } 2074 2075 /* 2076 * Adjust for the iteration. We have deleted the current 2077 * element and want to clear ATEDISK so the iteration does 2078 * not skip the element after, which now becomes the current 2079 * element. This element must be re-tested if doing an 2080 * iteration, which is handled by the RETEST flag. 2081 */ 2082 if ((cursor->flags & HAMMER_CURSOR_DISKEOF) == 0) { 2083 cursor->flags |= HAMMER_CURSOR_RETEST; 2084 cursor->flags &= ~HAMMER_CURSOR_ATEDISK; 2085 } 2086 2087 /* 2088 * An on-disk record cannot have the same delete_tid 2089 * as its create_tid. In a chain of record updates 2090 * this could result in a duplicate record. 2091 */ 2092 KKASSERT(elm->leaf.base.delete_tid != 2093 elm->leaf.base.create_tid); 2094 } 2095 2096 /* 2097 * Destroy the B-Tree element if asked (typically if a nohistory 2098 * file or mount, or when called by the pruning code). 2099 * 2100 * Adjust the ATEDISK flag to properly support iterations. 2101 */ 2102 if (delete_flags & HAMMER_DELETE_DESTROY) { 2103 data_offset = elm->leaf.data_offset; 2104 data_len = elm->leaf.data_len; 2105 rec_type = elm->leaf.base.rec_type; 2106 if (doprop) { 2107 save_leaf = elm->leaf; 2108 leaf = &save_leaf; 2109 } 2110 if (elm->base.rec_type == HAMMER_RECTYPE_INODE && 2111 elm->leaf.base.delete_tid == 0) { 2112 icount = -1; 2113 } 2114 2115 error = hammer_btree_delete(cursor); 2116 if (error == 0) { 2117 /* 2118 * The deletion moves the next element (if any) to 2119 * the current element position. We must clear 2120 * ATEDISK so this element is not skipped and we 2121 * must set RETEST to force any iteration to re-test 2122 * the element. 2123 */ 2124 if ((cursor->flags & HAMMER_CURSOR_DISKEOF) == 0) { 2125 cursor->flags |= HAMMER_CURSOR_RETEST; 2126 cursor->flags &= ~HAMMER_CURSOR_ATEDISK; 2127 } 2128 } 2129 if (error == 0) { 2130 switch(data_offset & HAMMER_OFF_ZONE_MASK) { 2131 case HAMMER_ZONE_LARGE_DATA: 2132 case HAMMER_ZONE_SMALL_DATA: 2133 case HAMMER_ZONE_META: 2134 hammer_blockmap_free(trans, 2135 data_offset, data_len); 2136 break; 2137 default: 2138 break; 2139 } 2140 } 2141 } 2142 2143 /* 2144 * Track inode count and next_tid. This is used by the mirroring 2145 * and PFS code. icount can be negative, zero, or positive. 2146 */ 2147 if (error == 0 && track) { 2148 if (icount) { 2149 hammer_modify_volume_field(trans, trans->rootvol, 2150 vol0_stat_inodes); 2151 trans->rootvol->ondisk->vol0_stat_inodes += icount; 2152 hammer_modify_volume_done(trans->rootvol); 2153 } 2154 if (trans->rootvol->ondisk->vol0_next_tid < delete_tid) { 2155 hammer_modify_volume(trans, trans->rootvol, NULL, 0); 2156 trans->rootvol->ondisk->vol0_next_tid = delete_tid; 2157 hammer_modify_volume_done(trans->rootvol); 2158 } 2159 } 2160 2161 /* 2162 * mirror_tid propagation occurs if the node's mirror_tid had to be 2163 * updated while adjusting the delete_tid. 2164 * 2165 * This occurs when deleting even in nohistory mode, but does not 2166 * occur when pruning an already-deleted node. 2167 * 2168 * cursor->ip is NULL when called from the pruning, mirroring, 2169 * and pfs code. If non-NULL propagation will be conditionalized 2170 * on whether the PFS is in no-history mode or not. 2171 */ 2172 if (doprop) { 2173 if (cursor->ip) 2174 hammer_btree_do_propagation(cursor, cursor->ip->pfsm, leaf); 2175 else 2176 hammer_btree_do_propagation(cursor, NULL, leaf); 2177 } 2178 hammer_sync_unlock(trans); 2179 return (error); 2180 } 2181 2182 /* 2183 * Determine whether we can remove a directory. This routine checks whether 2184 * a directory is empty or not and enforces flush connectivity. 2185 * 2186 * Flush connectivity requires that we block if the target directory is 2187 * currently flushing, otherwise it may not end up in the same flush group. 2188 * 2189 * Returns 0 on success, ENOTEMPTY or EDEADLK (or other errors) on failure. 2190 */ 2191 int 2192 hammer_ip_check_directory_empty(hammer_transaction_t trans, hammer_inode_t ip) 2193 { 2194 struct hammer_cursor cursor; 2195 int error; 2196 2197 /* 2198 * Check directory empty 2199 */ 2200 hammer_init_cursor(trans, &cursor, &ip->cache[1], ip); 2201 2202 cursor.key_beg.localization = ip->obj_localization + 2203 HAMMER_LOCALIZE_MISC; 2204 cursor.key_beg.obj_id = ip->obj_id; 2205 cursor.key_beg.create_tid = 0; 2206 cursor.key_beg.delete_tid = 0; 2207 cursor.key_beg.obj_type = 0; 2208 cursor.key_beg.rec_type = HAMMER_RECTYPE_INODE + 1; 2209 cursor.key_beg.key = HAMMER_MIN_KEY; 2210 2211 cursor.key_end = cursor.key_beg; 2212 cursor.key_end.rec_type = 0xFFFF; 2213 cursor.key_end.key = HAMMER_MAX_KEY; 2214 2215 cursor.asof = ip->obj_asof; 2216 cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF; 2217 2218 error = hammer_ip_first(&cursor); 2219 if (error == ENOENT) 2220 error = 0; 2221 else if (error == 0) 2222 error = ENOTEMPTY; 2223 hammer_done_cursor(&cursor); 2224 return(error); 2225 } 2226 2227