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_ondisk.c,v 1.76 2008/08/29 20:19:08 dillon Exp $ 35 */ 36 /* 37 * Manage HAMMER's on-disk structures. These routines are primarily 38 * responsible for interfacing with the kernel's I/O subsystem and for 39 * managing in-memory structures. 40 */ 41 42 #include "hammer.h" 43 #include <sys/fcntl.h> 44 #include <sys/nlookup.h> 45 #include <sys/buf.h> 46 47 #include <sys/buf2.h> 48 49 static void hammer_free_volume(hammer_volume_t volume); 50 static int hammer_load_volume(hammer_volume_t volume); 51 static int hammer_load_buffer(hammer_buffer_t buffer, int isnew); 52 static int hammer_load_node(hammer_transaction_t trans, 53 hammer_node_t node, int isnew); 54 static void _hammer_rel_node(hammer_node_t node, int locked); 55 56 static int 57 hammer_vol_rb_compare(hammer_volume_t vol1, hammer_volume_t vol2) 58 { 59 if (vol1->vol_no < vol2->vol_no) 60 return(-1); 61 if (vol1->vol_no > vol2->vol_no) 62 return(1); 63 return(0); 64 } 65 66 /* 67 * hammer_buffer structures are indexed via their zoneX_offset, not 68 * their zone2_offset. 69 */ 70 static int 71 hammer_buf_rb_compare(hammer_buffer_t buf1, hammer_buffer_t buf2) 72 { 73 if (buf1->zoneX_offset < buf2->zoneX_offset) 74 return(-1); 75 if (buf1->zoneX_offset > buf2->zoneX_offset) 76 return(1); 77 return(0); 78 } 79 80 static int 81 hammer_nod_rb_compare(hammer_node_t node1, hammer_node_t node2) 82 { 83 if (node1->node_offset < node2->node_offset) 84 return(-1); 85 if (node1->node_offset > node2->node_offset) 86 return(1); 87 return(0); 88 } 89 90 RB_GENERATE2(hammer_vol_rb_tree, hammer_volume, rb_node, 91 hammer_vol_rb_compare, int32_t, vol_no); 92 RB_GENERATE2(hammer_buf_rb_tree, hammer_buffer, rb_node, 93 hammer_buf_rb_compare, hammer_off_t, zoneX_offset); 94 RB_GENERATE2(hammer_nod_rb_tree, hammer_node, rb_node, 95 hammer_nod_rb_compare, hammer_off_t, node_offset); 96 97 /************************************************************************ 98 * VOLUMES * 99 ************************************************************************ 100 * 101 * Load a HAMMER volume by name. Returns 0 on success or a positive error 102 * code on failure. Volumes must be loaded at mount time, hammer_get_volume() 103 * will not load a new volume. 104 * 105 * The passed devvp is vref()'d but not locked. This function consumes the 106 * ref (typically by associating it with the volume structure). 107 * 108 * Calls made to hammer_load_volume() or single-threaded 109 */ 110 int 111 hammer_install_volume(struct hammer_mount *hmp, const char *volname, 112 struct vnode *devvp) 113 { 114 struct mount *mp; 115 hammer_volume_t volume; 116 struct hammer_volume_ondisk *ondisk; 117 struct nlookupdata nd; 118 struct buf *bp = NULL; 119 int error; 120 int ronly; 121 int setmp = 0; 122 123 mp = hmp->mp; 124 ronly = ((mp->mnt_flag & MNT_RDONLY) ? 1 : 0); 125 126 /* 127 * Allocate a volume structure 128 */ 129 ++hammer_count_volumes; 130 volume = kmalloc(sizeof(*volume), hmp->m_misc, M_WAITOK|M_ZERO); 131 volume->vol_name = kstrdup(volname, hmp->m_misc); 132 volume->io.hmp = hmp; /* bootstrap */ 133 hammer_io_init(&volume->io, volume, HAMMER_STRUCTURE_VOLUME); 134 volume->io.offset = 0LL; 135 volume->io.bytes = HAMMER_BUFSIZE; 136 137 /* 138 * Get the device vnode 139 */ 140 if (devvp == NULL) { 141 error = nlookup_init(&nd, volume->vol_name, UIO_SYSSPACE, NLC_FOLLOW); 142 if (error == 0) 143 error = nlookup(&nd); 144 if (error == 0) 145 error = cache_vref(&nd.nl_nch, nd.nl_cred, &volume->devvp); 146 nlookup_done(&nd); 147 } else { 148 error = 0; 149 volume->devvp = devvp; 150 } 151 152 if (error == 0) { 153 if (vn_isdisk(volume->devvp, &error)) { 154 error = vfs_mountedon(volume->devvp); 155 } 156 } 157 if (error == 0 && vcount(volume->devvp) > 0) 158 error = EBUSY; 159 if (error == 0) { 160 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 161 error = vinvalbuf(volume->devvp, V_SAVE, 0, 0); 162 if (error == 0) { 163 error = VOP_OPEN(volume->devvp, 164 (ronly ? FREAD : FREAD|FWRITE), 165 FSCRED, NULL); 166 } 167 vn_unlock(volume->devvp); 168 } 169 if (error) { 170 hammer_free_volume(volume); 171 return(error); 172 } 173 volume->devvp->v_rdev->si_mountpoint = mp; 174 setmp = 1; 175 176 /* 177 * Extract the volume number from the volume header and do various 178 * sanity checks. 179 */ 180 error = bread(volume->devvp, 0LL, HAMMER_BUFSIZE, &bp); 181 if (error) 182 goto late_failure; 183 ondisk = (void *)bp->b_data; 184 if (ondisk->vol_signature != HAMMER_FSBUF_VOLUME) { 185 kprintf("hammer_mount: volume %s has an invalid header\n", 186 volume->vol_name); 187 error = EFTYPE; 188 goto late_failure; 189 } 190 volume->vol_no = ondisk->vol_no; 191 volume->buffer_base = ondisk->vol_buf_beg; 192 volume->vol_flags = ondisk->vol_flags; 193 volume->nblocks = ondisk->vol_nblocks; 194 volume->maxbuf_off = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 195 ondisk->vol_buf_end - ondisk->vol_buf_beg); 196 volume->maxraw_off = ondisk->vol_buf_end; 197 198 if (RB_EMPTY(&hmp->rb_vols_root)) { 199 hmp->fsid = ondisk->vol_fsid; 200 } else if (bcmp(&hmp->fsid, &ondisk->vol_fsid, sizeof(uuid_t))) { 201 kprintf("hammer_mount: volume %s's fsid does not match " 202 "other volumes\n", volume->vol_name); 203 error = EFTYPE; 204 goto late_failure; 205 } 206 207 /* 208 * Insert the volume structure into the red-black tree. 209 */ 210 if (RB_INSERT(hammer_vol_rb_tree, &hmp->rb_vols_root, volume)) { 211 kprintf("hammer_mount: volume %s has a duplicate vol_no %d\n", 212 volume->vol_name, volume->vol_no); 213 error = EEXIST; 214 } 215 216 /* 217 * Set the root volume . HAMMER special cases rootvol the structure. 218 * We do not hold a ref because this would prevent related I/O 219 * from being flushed. 220 */ 221 if (error == 0 && ondisk->vol_rootvol == ondisk->vol_no) { 222 hmp->rootvol = volume; 223 hmp->nvolumes = ondisk->vol_count; 224 if (bp) { 225 brelse(bp); 226 bp = NULL; 227 } 228 hmp->mp->mnt_stat.f_blocks += ondisk->vol0_stat_bigblocks * 229 (HAMMER_BIGBLOCK_SIZE / HAMMER_BUFSIZE); 230 hmp->mp->mnt_vstat.f_blocks += ondisk->vol0_stat_bigblocks * 231 (HAMMER_BIGBLOCK_SIZE / HAMMER_BUFSIZE); 232 } 233 late_failure: 234 if (bp) 235 brelse(bp); 236 if (error) { 237 /*vinvalbuf(volume->devvp, V_SAVE, 0, 0);*/ 238 if (setmp) 239 volume->devvp->v_rdev->si_mountpoint = NULL; 240 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 241 VOP_CLOSE(volume->devvp, ronly ? FREAD : FREAD|FWRITE, NULL); 242 vn_unlock(volume->devvp); 243 hammer_free_volume(volume); 244 } 245 return (error); 246 } 247 248 /* 249 * This is called for each volume when updating the mount point from 250 * read-write to read-only or vise-versa. 251 */ 252 int 253 hammer_adjust_volume_mode(hammer_volume_t volume, void *data __unused) 254 { 255 if (volume->devvp) { 256 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 257 if (volume->io.hmp->ronly) { 258 /* do not call vinvalbuf */ 259 VOP_OPEN(volume->devvp, FREAD, FSCRED, NULL); 260 VOP_CLOSE(volume->devvp, FREAD|FWRITE, NULL); 261 } else { 262 /* do not call vinvalbuf */ 263 VOP_OPEN(volume->devvp, FREAD|FWRITE, FSCRED, NULL); 264 VOP_CLOSE(volume->devvp, FREAD, NULL); 265 } 266 vn_unlock(volume->devvp); 267 } 268 return(0); 269 } 270 271 /* 272 * Unload and free a HAMMER volume. Must return >= 0 to continue scan 273 * so returns -1 on failure. 274 */ 275 int 276 hammer_unload_volume(hammer_volume_t volume, void *data __unused) 277 { 278 hammer_mount_t hmp = volume->io.hmp; 279 int ronly = ((hmp->mp->mnt_flag & MNT_RDONLY) ? 1 : 0); 280 281 /* 282 * Clean up the root volume pointer, which is held unlocked in hmp. 283 */ 284 if (hmp->rootvol == volume) 285 hmp->rootvol = NULL; 286 287 /* 288 * We must not flush a dirty buffer to disk on umount. It should 289 * have already been dealt with by the flusher, or we may be in 290 * catastrophic failure. 291 */ 292 hammer_io_clear_modify(&volume->io, 1); 293 volume->io.waitdep = 1; 294 295 /* 296 * Clean up the persistent ref ioerror might have on the volume 297 */ 298 if (volume->io.ioerror) 299 hammer_io_clear_error_noassert(&volume->io); 300 301 /* 302 * This should release the bp. Releasing the volume with flush set 303 * implies the interlock is set. 304 */ 305 hammer_ref_interlock_true(&volume->io.lock); 306 hammer_rel_volume(volume, 1); 307 KKASSERT(volume->io.bp == NULL); 308 309 /* 310 * There should be no references on the volume, no clusters, and 311 * no super-clusters. 312 */ 313 KKASSERT(hammer_norefs(&volume->io.lock)); 314 315 volume->ondisk = NULL; 316 if (volume->devvp) { 317 if (volume->devvp->v_rdev && 318 volume->devvp->v_rdev->si_mountpoint == hmp->mp 319 ) { 320 volume->devvp->v_rdev->si_mountpoint = NULL; 321 } 322 if (ronly) { 323 /* 324 * Make sure we don't sync anything to disk if we 325 * are in read-only mode (1) or critically-errored 326 * (2). Note that there may be dirty buffers in 327 * normal read-only mode from crash recovery. 328 */ 329 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 330 vinvalbuf(volume->devvp, 0, 0, 0); 331 VOP_CLOSE(volume->devvp, FREAD, NULL); 332 vn_unlock(volume->devvp); 333 } else { 334 /* 335 * Normal termination, save any dirty buffers 336 * (XXX there really shouldn't be any). 337 */ 338 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 339 vinvalbuf(volume->devvp, V_SAVE, 0, 0); 340 VOP_CLOSE(volume->devvp, FREAD|FWRITE, NULL); 341 vn_unlock(volume->devvp); 342 } 343 } 344 345 /* 346 * Destroy the structure 347 */ 348 RB_REMOVE(hammer_vol_rb_tree, &hmp->rb_vols_root, volume); 349 hammer_free_volume(volume); 350 return(0); 351 } 352 353 static 354 void 355 hammer_free_volume(hammer_volume_t volume) 356 { 357 hammer_mount_t hmp = volume->io.hmp; 358 359 if (volume->vol_name) { 360 kfree(volume->vol_name, hmp->m_misc); 361 volume->vol_name = NULL; 362 } 363 if (volume->devvp) { 364 vrele(volume->devvp); 365 volume->devvp = NULL; 366 } 367 --hammer_count_volumes; 368 kfree(volume, hmp->m_misc); 369 } 370 371 /* 372 * Get a HAMMER volume. The volume must already exist. 373 */ 374 hammer_volume_t 375 hammer_get_volume(struct hammer_mount *hmp, int32_t vol_no, int *errorp) 376 { 377 struct hammer_volume *volume; 378 379 /* 380 * Locate the volume structure 381 */ 382 volume = RB_LOOKUP(hammer_vol_rb_tree, &hmp->rb_vols_root, vol_no); 383 if (volume == NULL) { 384 *errorp = ENOENT; 385 return(NULL); 386 } 387 388 /* 389 * Reference the volume, load/check the data on the 0->1 transition. 390 * hammer_load_volume() will dispose of the interlock on return, 391 * and also clean up the ref count on error. 392 */ 393 if (hammer_ref_interlock(&volume->io.lock)) { 394 *errorp = hammer_load_volume(volume); 395 if (*errorp) 396 volume = NULL; 397 } else { 398 KKASSERT(volume->ondisk); 399 *errorp = 0; 400 } 401 return(volume); 402 } 403 404 int 405 hammer_ref_volume(hammer_volume_t volume) 406 { 407 int error; 408 409 /* 410 * Reference the volume and deal with the check condition used to 411 * load its ondisk info. 412 */ 413 if (hammer_ref_interlock(&volume->io.lock)) { 414 error = hammer_load_volume(volume); 415 } else { 416 KKASSERT(volume->ondisk); 417 error = 0; 418 } 419 return (error); 420 } 421 422 /* 423 * May be called without fs_token 424 */ 425 hammer_volume_t 426 hammer_get_root_volume(struct hammer_mount *hmp, int *errorp) 427 { 428 hammer_volume_t volume; 429 430 volume = hmp->rootvol; 431 KKASSERT(volume != NULL); 432 433 /* 434 * Reference the volume and deal with the check condition used to 435 * load its ondisk info. 436 */ 437 if (hammer_ref_interlock(&volume->io.lock)) { 438 lwkt_gettoken(&volume->io.hmp->fs_token); 439 *errorp = hammer_load_volume(volume); 440 lwkt_reltoken(&volume->io.hmp->fs_token); 441 if (*errorp) 442 volume = NULL; 443 } else { 444 KKASSERT(volume->ondisk); 445 *errorp = 0; 446 } 447 return (volume); 448 } 449 450 /* 451 * Load a volume's on-disk information. The volume must be referenced and 452 * the interlock is held on call. The interlock will be released on return. 453 * The reference will also be released on return if an error occurs. 454 */ 455 static int 456 hammer_load_volume(hammer_volume_t volume) 457 { 458 int error; 459 460 if (volume->ondisk == NULL) { 461 error = hammer_io_read(volume->devvp, &volume->io, 462 HAMMER_BUFSIZE); 463 if (error == 0) { 464 volume->ondisk = (void *)volume->io.bp->b_data; 465 hammer_ref_interlock_done(&volume->io.lock); 466 } else { 467 hammer_rel_volume(volume, 1); 468 } 469 } else { 470 error = 0; 471 } 472 return(error); 473 } 474 475 /* 476 * Release a previously acquired reference on the volume. 477 * 478 * Volumes are not unloaded from memory during normal operation. 479 * 480 * May be called without fs_token 481 */ 482 void 483 hammer_rel_volume(hammer_volume_t volume, int locked) 484 { 485 struct buf *bp; 486 487 if (hammer_rel_interlock(&volume->io.lock, locked)) { 488 lwkt_gettoken(&volume->io.hmp->fs_token); 489 volume->ondisk = NULL; 490 bp = hammer_io_release(&volume->io, locked); 491 lwkt_reltoken(&volume->io.hmp->fs_token); 492 hammer_rel_interlock_done(&volume->io.lock, locked); 493 if (bp) 494 brelse(bp); 495 } 496 } 497 498 int 499 hammer_mountcheck_volumes(struct hammer_mount *hmp) 500 { 501 hammer_volume_t vol; 502 int i; 503 504 for (i = 0; i < hmp->nvolumes; ++i) { 505 vol = RB_LOOKUP(hammer_vol_rb_tree, &hmp->rb_vols_root, i); 506 if (vol == NULL) 507 return(EINVAL); 508 } 509 return(0); 510 } 511 512 /************************************************************************ 513 * BUFFERS * 514 ************************************************************************ 515 * 516 * Manage buffers. Currently most blockmap-backed zones are direct-mapped 517 * to zone-2 buffer offsets, without a translation stage. However, the 518 * hammer_buffer structure is indexed by its zoneX_offset, not its 519 * zone2_offset. 520 * 521 * The proper zone must be maintained throughout the code-base all the way 522 * through to the big-block allocator, or routines like hammer_del_buffers() 523 * will not be able to locate all potentially conflicting buffers. 524 */ 525 526 /* 527 * Helper function returns whether a zone offset can be directly translated 528 * to a raw buffer index or not. Really only the volume and undo zones 529 * can't be directly translated. Volumes are special-cased and undo zones 530 * shouldn't be aliased accessed in read-only mode. 531 * 532 * This function is ONLY used to detect aliased zones during a read-only 533 * mount. 534 */ 535 static __inline int 536 hammer_direct_zone(hammer_off_t buf_offset) 537 { 538 switch(HAMMER_ZONE_DECODE(buf_offset)) { 539 case HAMMER_ZONE_RAW_BUFFER_INDEX: 540 case HAMMER_ZONE_FREEMAP_INDEX: 541 case HAMMER_ZONE_BTREE_INDEX: 542 case HAMMER_ZONE_META_INDEX: 543 case HAMMER_ZONE_LARGE_DATA_INDEX: 544 case HAMMER_ZONE_SMALL_DATA_INDEX: 545 return(1); 546 default: 547 return(0); 548 } 549 /* NOT REACHED */ 550 } 551 552 hammer_buffer_t 553 hammer_get_buffer(hammer_mount_t hmp, hammer_off_t buf_offset, 554 int bytes, int isnew, int *errorp) 555 { 556 hammer_buffer_t buffer; 557 hammer_volume_t volume; 558 hammer_off_t zone2_offset; 559 hammer_io_type_t iotype; 560 int vol_no; 561 int zone; 562 563 buf_offset &= ~HAMMER_BUFMASK64; 564 again: 565 /* 566 * Shortcut if the buffer is already cached 567 */ 568 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, buf_offset); 569 if (buffer) { 570 /* 571 * Once refed the ondisk field will not be cleared by 572 * any other action. Shortcut the operation if the 573 * ondisk structure is valid. 574 */ 575 found_aliased: 576 if (hammer_ref_interlock(&buffer->io.lock) == 0) { 577 hammer_io_advance(&buffer->io); 578 KKASSERT(buffer->ondisk); 579 *errorp = 0; 580 return(buffer); 581 } 582 583 /* 584 * 0->1 transition or defered 0->1 transition (CHECK), 585 * interlock now held. Shortcut if ondisk is already 586 * assigned. 587 */ 588 atomic_add_int(&hammer_count_refedbufs, 1); 589 if (buffer->ondisk) { 590 hammer_io_advance(&buffer->io); 591 hammer_ref_interlock_done(&buffer->io.lock); 592 *errorp = 0; 593 return(buffer); 594 } 595 596 /* 597 * The buffer is no longer loose if it has a ref, and 598 * cannot become loose once it gains a ref. Loose 599 * buffers will never be in a modified state. This should 600 * only occur on the 0->1 transition of refs. 601 * 602 * lose_list can be modified via a biodone() interrupt 603 * so the io_token must be held. 604 */ 605 if (buffer->io.mod_root == &hmp->lose_root) { 606 lwkt_gettoken(&hmp->io_token); 607 if (buffer->io.mod_root == &hmp->lose_root) { 608 RB_REMOVE(hammer_mod_rb_tree, 609 buffer->io.mod_root, &buffer->io); 610 buffer->io.mod_root = NULL; 611 KKASSERT(buffer->io.modified == 0); 612 } 613 lwkt_reltoken(&hmp->io_token); 614 } 615 goto found; 616 } else if (hmp->ronly && hammer_direct_zone(buf_offset)) { 617 /* 618 * If this is a read-only mount there could be an alias 619 * in the raw-zone. If there is we use that buffer instead. 620 * 621 * rw mounts will not have aliases. Also note when going 622 * from ro -> rw the recovered raw buffers are flushed and 623 * reclaimed, so again there will not be any aliases once 624 * the mount is rw. 625 */ 626 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 627 hammer_xlate_to_zone2(buf_offset)); 628 if (buffer) { 629 kprintf("HAMMER: recovered aliased %016jx\n", 630 (intmax_t)buf_offset); 631 goto found_aliased; 632 } 633 } 634 635 /* 636 * What is the buffer class? 637 */ 638 zone = HAMMER_ZONE_DECODE(buf_offset); 639 640 switch(zone) { 641 case HAMMER_ZONE_LARGE_DATA_INDEX: 642 case HAMMER_ZONE_SMALL_DATA_INDEX: 643 iotype = HAMMER_STRUCTURE_DATA_BUFFER; 644 break; 645 case HAMMER_ZONE_UNDO_INDEX: 646 iotype = HAMMER_STRUCTURE_UNDO_BUFFER; 647 break; 648 case HAMMER_ZONE_META_INDEX: 649 default: 650 /* 651 * NOTE: inode data and directory entries are placed in this 652 * zone. inode atime/mtime is updated in-place and thus 653 * buffers containing inodes must be synchronized as 654 * meta-buffers, same as buffers containing B-Tree info. 655 */ 656 iotype = HAMMER_STRUCTURE_META_BUFFER; 657 break; 658 } 659 660 /* 661 * Handle blockmap offset translations 662 */ 663 if (zone >= HAMMER_ZONE_BTREE_INDEX) { 664 zone2_offset = hammer_blockmap_lookup(hmp, buf_offset, errorp); 665 } else if (zone == HAMMER_ZONE_UNDO_INDEX) { 666 zone2_offset = hammer_undo_lookup(hmp, buf_offset, errorp); 667 } else { 668 KKASSERT(zone == HAMMER_ZONE_RAW_BUFFER_INDEX); 669 zone2_offset = buf_offset; 670 *errorp = 0; 671 } 672 if (*errorp) 673 return(NULL); 674 675 /* 676 * NOTE: zone2_offset and maxbuf_off are both full zone-2 offset 677 * specifications. 678 */ 679 KKASSERT((zone2_offset & HAMMER_OFF_ZONE_MASK) == 680 HAMMER_ZONE_RAW_BUFFER); 681 vol_no = HAMMER_VOL_DECODE(zone2_offset); 682 volume = hammer_get_volume(hmp, vol_no, errorp); 683 if (volume == NULL) 684 return(NULL); 685 686 KKASSERT(zone2_offset < volume->maxbuf_off); 687 688 /* 689 * Allocate a new buffer structure. We will check for races later. 690 */ 691 ++hammer_count_buffers; 692 buffer = kmalloc(sizeof(*buffer), hmp->m_misc, 693 M_WAITOK|M_ZERO|M_USE_RESERVE); 694 buffer->zone2_offset = zone2_offset; 695 buffer->zoneX_offset = buf_offset; 696 697 hammer_io_init(&buffer->io, volume, iotype); 698 buffer->io.offset = volume->ondisk->vol_buf_beg + 699 (zone2_offset & HAMMER_OFF_SHORT_MASK); 700 buffer->io.bytes = bytes; 701 TAILQ_INIT(&buffer->clist); 702 hammer_ref_interlock_true(&buffer->io.lock); 703 704 /* 705 * Insert the buffer into the RB tree and handle late collisions. 706 */ 707 if (RB_INSERT(hammer_buf_rb_tree, &hmp->rb_bufs_root, buffer)) { 708 hammer_rel_volume(volume, 0); 709 buffer->io.volume = NULL; /* safety */ 710 if (hammer_rel_interlock(&buffer->io.lock, 1)) /* safety */ 711 hammer_rel_interlock_done(&buffer->io.lock, 1); 712 --hammer_count_buffers; 713 kfree(buffer, hmp->m_misc); 714 goto again; 715 } 716 atomic_add_int(&hammer_count_refedbufs, 1); 717 found: 718 719 /* 720 * The buffer is referenced and interlocked. Load the buffer 721 * if necessary. hammer_load_buffer() deals with the interlock 722 * and, if an error is returned, also deals with the ref. 723 */ 724 if (buffer->ondisk == NULL) { 725 *errorp = hammer_load_buffer(buffer, isnew); 726 if (*errorp) 727 buffer = NULL; 728 } else { 729 hammer_io_advance(&buffer->io); 730 hammer_ref_interlock_done(&buffer->io.lock); 731 *errorp = 0; 732 } 733 return(buffer); 734 } 735 736 /* 737 * This is used by the direct-read code to deal with large-data buffers 738 * created by the reblocker and mirror-write code. The direct-read code 739 * bypasses the HAMMER buffer subsystem and so any aliased dirty or write- 740 * running hammer buffers must be fully synced to disk before we can issue 741 * the direct-read. 742 * 743 * This code path is not considered critical as only the rebocker and 744 * mirror-write code will create large-data buffers via the HAMMER buffer 745 * subsystem. They do that because they operate at the B-Tree level and 746 * do not access the vnode/inode structures. 747 */ 748 void 749 hammer_sync_buffers(hammer_mount_t hmp, hammer_off_t base_offset, int bytes) 750 { 751 hammer_buffer_t buffer; 752 int error; 753 754 KKASSERT((base_offset & HAMMER_OFF_ZONE_MASK) == 755 HAMMER_ZONE_LARGE_DATA); 756 757 while (bytes > 0) { 758 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 759 base_offset); 760 if (buffer && (buffer->io.modified || buffer->io.running)) { 761 error = hammer_ref_buffer(buffer); 762 if (error == 0) { 763 hammer_io_wait(&buffer->io); 764 if (buffer->io.modified) { 765 hammer_io_write_interlock(&buffer->io); 766 hammer_io_flush(&buffer->io, 0); 767 hammer_io_done_interlock(&buffer->io); 768 hammer_io_wait(&buffer->io); 769 } 770 hammer_rel_buffer(buffer, 0); 771 } 772 } 773 base_offset += HAMMER_BUFSIZE; 774 bytes -= HAMMER_BUFSIZE; 775 } 776 } 777 778 /* 779 * Destroy all buffers covering the specified zoneX offset range. This 780 * is called when the related blockmap layer2 entry is freed or when 781 * a direct write bypasses our buffer/buffer-cache subsystem. 782 * 783 * The buffers may be referenced by the caller itself. Setting reclaim 784 * will cause the buffer to be destroyed when it's ref count reaches zero. 785 * 786 * Return 0 on success, EAGAIN if some buffers could not be destroyed due 787 * to additional references held by other threads, or some other (typically 788 * fatal) error. 789 */ 790 int 791 hammer_del_buffers(hammer_mount_t hmp, hammer_off_t base_offset, 792 hammer_off_t zone2_offset, int bytes, 793 int report_conflicts) 794 { 795 hammer_buffer_t buffer; 796 hammer_volume_t volume; 797 int vol_no; 798 int error; 799 int ret_error; 800 801 vol_no = HAMMER_VOL_DECODE(zone2_offset); 802 volume = hammer_get_volume(hmp, vol_no, &ret_error); 803 KKASSERT(ret_error == 0); 804 805 while (bytes > 0) { 806 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 807 base_offset); 808 if (buffer) { 809 error = hammer_ref_buffer(buffer); 810 if (hammer_debug_general & 0x20000) { 811 kprintf("hammer: delbufr %016jx " 812 "rerr=%d 1ref=%d\n", 813 (intmax_t)buffer->zoneX_offset, 814 error, 815 hammer_oneref(&buffer->io.lock)); 816 } 817 if (error == 0 && !hammer_oneref(&buffer->io.lock)) { 818 error = EAGAIN; 819 hammer_rel_buffer(buffer, 0); 820 } 821 if (error == 0) { 822 KKASSERT(buffer->zone2_offset == zone2_offset); 823 hammer_io_clear_modify(&buffer->io, 1); 824 buffer->io.reclaim = 1; 825 buffer->io.waitdep = 1; 826 KKASSERT(buffer->io.volume == volume); 827 hammer_rel_buffer(buffer, 0); 828 } 829 } else { 830 error = hammer_io_inval(volume, zone2_offset); 831 } 832 if (error) { 833 ret_error = error; 834 if (report_conflicts || 835 (hammer_debug_general & 0x8000)) { 836 kprintf("hammer_del_buffers: unable to " 837 "invalidate %016llx buffer=%p rep=%d\n", 838 (long long)base_offset, 839 buffer, report_conflicts); 840 } 841 } 842 base_offset += HAMMER_BUFSIZE; 843 zone2_offset += HAMMER_BUFSIZE; 844 bytes -= HAMMER_BUFSIZE; 845 } 846 hammer_rel_volume(volume, 0); 847 return (ret_error); 848 } 849 850 /* 851 * Given a referenced and interlocked buffer load/validate the data. 852 * 853 * The buffer interlock will be released on return. If an error is 854 * returned the buffer reference will also be released (and the buffer 855 * pointer will thus be stale). 856 */ 857 static int 858 hammer_load_buffer(hammer_buffer_t buffer, int isnew) 859 { 860 hammer_volume_t volume; 861 int error; 862 863 /* 864 * Load the buffer's on-disk info 865 */ 866 volume = buffer->io.volume; 867 868 if (hammer_debug_io & 0x0004) { 869 kprintf("load_buffer %016llx %016llx isnew=%d od=%p\n", 870 (long long)buffer->zoneX_offset, 871 (long long)buffer->zone2_offset, 872 isnew, buffer->ondisk); 873 } 874 875 if (buffer->ondisk == NULL) { 876 /* 877 * Issue the read or generate a new buffer. When reading 878 * the limit argument controls any read-ahead clustering 879 * hammer_io_read() is allowed to do. 880 * 881 * We cannot read-ahead in the large-data zone and we cannot 882 * cross a big-block boundary as the next big-block might 883 * use a different buffer size. 884 */ 885 if (isnew) { 886 error = hammer_io_new(volume->devvp, &buffer->io); 887 } else if ((buffer->zoneX_offset & HAMMER_OFF_ZONE_MASK) == 888 HAMMER_ZONE_LARGE_DATA) { 889 error = hammer_io_read(volume->devvp, &buffer->io, 890 buffer->io.bytes); 891 } else { 892 hammer_off_t limit; 893 894 limit = (buffer->zone2_offset + 895 HAMMER_BIGBLOCK_MASK64) & 896 ~HAMMER_BIGBLOCK_MASK64; 897 limit -= buffer->zone2_offset; 898 error = hammer_io_read(volume->devvp, &buffer->io, 899 limit); 900 } 901 if (error == 0) 902 buffer->ondisk = (void *)buffer->io.bp->b_data; 903 } else if (isnew) { 904 error = hammer_io_new(volume->devvp, &buffer->io); 905 } else { 906 error = 0; 907 } 908 if (error == 0) { 909 hammer_io_advance(&buffer->io); 910 hammer_ref_interlock_done(&buffer->io.lock); 911 } else { 912 hammer_rel_buffer(buffer, 1); 913 } 914 return (error); 915 } 916 917 /* 918 * NOTE: Called from RB_SCAN, must return >= 0 for scan to continue. 919 * This routine is only called during unmount or when a volume is 920 * removed. 921 * 922 * If data != NULL, it specifies a volume whoose buffers should 923 * be unloaded. 924 */ 925 int 926 hammer_unload_buffer(hammer_buffer_t buffer, void *data) 927 { 928 struct hammer_volume *volume = (struct hammer_volume *) data; 929 930 /* 931 * If volume != NULL we are only interested in unloading buffers 932 * associated with a particular volume. 933 */ 934 if (volume != NULL && volume != buffer->io.volume) 935 return 0; 936 937 /* 938 * Clean up the persistent ref ioerror might have on the buffer 939 * and acquire a ref. Expect a 0->1 transition. 940 */ 941 if (buffer->io.ioerror) { 942 hammer_io_clear_error_noassert(&buffer->io); 943 atomic_add_int(&hammer_count_refedbufs, -1); 944 } 945 hammer_ref_interlock_true(&buffer->io.lock); 946 atomic_add_int(&hammer_count_refedbufs, 1); 947 948 /* 949 * We must not flush a dirty buffer to disk on umount. It should 950 * have already been dealt with by the flusher, or we may be in 951 * catastrophic failure. 952 * 953 * We must set waitdep to ensure that a running buffer is waited 954 * on and released prior to us trying to unload the volume. 955 */ 956 hammer_io_clear_modify(&buffer->io, 1); 957 hammer_flush_buffer_nodes(buffer); 958 buffer->io.waitdep = 1; 959 hammer_rel_buffer(buffer, 1); 960 return(0); 961 } 962 963 /* 964 * Reference a buffer that is either already referenced or via a specially 965 * handled pointer (aka cursor->buffer). 966 */ 967 int 968 hammer_ref_buffer(hammer_buffer_t buffer) 969 { 970 hammer_mount_t hmp; 971 int error; 972 int locked; 973 974 /* 975 * Acquire a ref, plus the buffer will be interlocked on the 976 * 0->1 transition. 977 */ 978 locked = hammer_ref_interlock(&buffer->io.lock); 979 hmp = buffer->io.hmp; 980 981 /* 982 * At this point a biodone() will not touch the buffer other then 983 * incidental bits. However, lose_list can be modified via 984 * a biodone() interrupt. 985 * 986 * No longer loose. lose_list requires the io_token. 987 */ 988 if (buffer->io.mod_root == &hmp->lose_root) { 989 lwkt_gettoken(&hmp->io_token); 990 if (buffer->io.mod_root == &hmp->lose_root) { 991 RB_REMOVE(hammer_mod_rb_tree, 992 buffer->io.mod_root, &buffer->io); 993 buffer->io.mod_root = NULL; 994 } 995 lwkt_reltoken(&hmp->io_token); 996 } 997 998 if (locked) { 999 atomic_add_int(&hammer_count_refedbufs, 1); 1000 error = hammer_load_buffer(buffer, 0); 1001 /* NOTE: on error the buffer pointer is stale */ 1002 } else { 1003 error = 0; 1004 } 1005 return(error); 1006 } 1007 1008 /* 1009 * Release a reference on the buffer. On the 1->0 transition the 1010 * underlying IO will be released but the data reference is left 1011 * cached. 1012 * 1013 * Only destroy the structure itself if the related buffer cache buffer 1014 * was disassociated from it. This ties the management of the structure 1015 * to the buffer cache subsystem. buffer->ondisk determines whether the 1016 * embedded io is referenced or not. 1017 */ 1018 void 1019 hammer_rel_buffer(hammer_buffer_t buffer, int locked) 1020 { 1021 hammer_volume_t volume; 1022 hammer_mount_t hmp; 1023 struct buf *bp = NULL; 1024 int freeme = 0; 1025 1026 hmp = buffer->io.hmp; 1027 1028 if (hammer_rel_interlock(&buffer->io.lock, locked) == 0) 1029 return; 1030 1031 /* 1032 * hammer_count_refedbufs accounting. Decrement if we are in 1033 * the error path or if CHECK is clear. 1034 * 1035 * If we are not in the error path and CHECK is set the caller 1036 * probably just did a hammer_ref() and didn't account for it, 1037 * so we don't account for the loss here. 1038 */ 1039 if (locked || (buffer->io.lock.refs & HAMMER_REFS_CHECK) == 0) 1040 atomic_add_int(&hammer_count_refedbufs, -1); 1041 1042 /* 1043 * If the caller locked us or the normal released transitions 1044 * from 1->0 (and acquired the lock) attempt to release the 1045 * io. If the called locked us we tell hammer_io_release() 1046 * to flush (which would be the unload or failure path). 1047 */ 1048 bp = hammer_io_release(&buffer->io, locked); 1049 1050 /* 1051 * If the buffer has no bp association and no refs we can destroy 1052 * it. 1053 * 1054 * NOTE: It is impossible for any associated B-Tree nodes to have 1055 * refs if the buffer has no additional refs. 1056 */ 1057 if (buffer->io.bp == NULL && hammer_norefs(&buffer->io.lock)) { 1058 RB_REMOVE(hammer_buf_rb_tree, 1059 &buffer->io.hmp->rb_bufs_root, 1060 buffer); 1061 volume = buffer->io.volume; 1062 buffer->io.volume = NULL; /* sanity */ 1063 hammer_rel_volume(volume, 0); 1064 hammer_io_clear_modlist(&buffer->io); 1065 hammer_flush_buffer_nodes(buffer); 1066 KKASSERT(TAILQ_EMPTY(&buffer->clist)); 1067 freeme = 1; 1068 } 1069 1070 /* 1071 * Cleanup 1072 */ 1073 hammer_rel_interlock_done(&buffer->io.lock, locked); 1074 if (bp) 1075 brelse(bp); 1076 if (freeme) { 1077 --hammer_count_buffers; 1078 kfree(buffer, hmp->m_misc); 1079 } 1080 } 1081 1082 /* 1083 * Access the filesystem buffer containing the specified hammer offset. 1084 * buf_offset is a conglomeration of the volume number and vol_buf_beg 1085 * relative buffer offset. It must also have bit 55 set to be valid. 1086 * (see hammer_off_t in hammer_disk.h). 1087 * 1088 * Any prior buffer in *bufferp will be released and replaced by the 1089 * requested buffer. 1090 * 1091 * NOTE: The buffer is indexed via its zoneX_offset but we allow the 1092 * passed cached *bufferp to match against either zoneX or zone2. 1093 */ 1094 static __inline 1095 void * 1096 _hammer_bread(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1097 int *errorp, struct hammer_buffer **bufferp) 1098 { 1099 hammer_buffer_t buffer; 1100 int32_t xoff = (int32_t)buf_offset & HAMMER_BUFMASK; 1101 1102 buf_offset &= ~HAMMER_BUFMASK64; 1103 KKASSERT((buf_offset & HAMMER_OFF_ZONE_MASK) != 0); 1104 1105 buffer = *bufferp; 1106 if (buffer == NULL || (buffer->zone2_offset != buf_offset && 1107 buffer->zoneX_offset != buf_offset)) { 1108 if (buffer) 1109 hammer_rel_buffer(buffer, 0); 1110 buffer = hammer_get_buffer(hmp, buf_offset, bytes, 0, errorp); 1111 *bufferp = buffer; 1112 } else { 1113 *errorp = 0; 1114 } 1115 1116 /* 1117 * Return a pointer to the buffer data. 1118 */ 1119 if (buffer == NULL) 1120 return(NULL); 1121 else 1122 return((char *)buffer->ondisk + xoff); 1123 } 1124 1125 void * 1126 hammer_bread(hammer_mount_t hmp, hammer_off_t buf_offset, 1127 int *errorp, struct hammer_buffer **bufferp) 1128 { 1129 return(_hammer_bread(hmp, buf_offset, HAMMER_BUFSIZE, errorp, bufferp)); 1130 } 1131 1132 void * 1133 hammer_bread_ext(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1134 int *errorp, struct hammer_buffer **bufferp) 1135 { 1136 bytes = (bytes + HAMMER_BUFMASK) & ~HAMMER_BUFMASK; 1137 return(_hammer_bread(hmp, buf_offset, bytes, errorp, bufferp)); 1138 } 1139 1140 /* 1141 * Access the filesystem buffer containing the specified hammer offset. 1142 * No disk read operation occurs. The result buffer may contain garbage. 1143 * 1144 * Any prior buffer in *bufferp will be released and replaced by the 1145 * requested buffer. 1146 * 1147 * This function marks the buffer dirty but does not increment its 1148 * modify_refs count. 1149 */ 1150 static __inline 1151 void * 1152 _hammer_bnew(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1153 int *errorp, struct hammer_buffer **bufferp) 1154 { 1155 hammer_buffer_t buffer; 1156 int32_t xoff = (int32_t)buf_offset & HAMMER_BUFMASK; 1157 1158 buf_offset &= ~HAMMER_BUFMASK64; 1159 1160 buffer = *bufferp; 1161 if (buffer == NULL || (buffer->zone2_offset != buf_offset && 1162 buffer->zoneX_offset != buf_offset)) { 1163 if (buffer) 1164 hammer_rel_buffer(buffer, 0); 1165 buffer = hammer_get_buffer(hmp, buf_offset, bytes, 1, errorp); 1166 *bufferp = buffer; 1167 } else { 1168 *errorp = 0; 1169 } 1170 1171 /* 1172 * Return a pointer to the buffer data. 1173 */ 1174 if (buffer == NULL) 1175 return(NULL); 1176 else 1177 return((char *)buffer->ondisk + xoff); 1178 } 1179 1180 void * 1181 hammer_bnew(hammer_mount_t hmp, hammer_off_t buf_offset, 1182 int *errorp, struct hammer_buffer **bufferp) 1183 { 1184 return(_hammer_bnew(hmp, buf_offset, HAMMER_BUFSIZE, errorp, bufferp)); 1185 } 1186 1187 void * 1188 hammer_bnew_ext(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1189 int *errorp, struct hammer_buffer **bufferp) 1190 { 1191 bytes = (bytes + HAMMER_BUFMASK) & ~HAMMER_BUFMASK; 1192 return(_hammer_bnew(hmp, buf_offset, bytes, errorp, bufferp)); 1193 } 1194 1195 /************************************************************************ 1196 * NODES * 1197 ************************************************************************ 1198 * 1199 * Manage B-Tree nodes. B-Tree nodes represent the primary indexing 1200 * method used by the HAMMER filesystem. 1201 * 1202 * Unlike other HAMMER structures, a hammer_node can be PASSIVELY 1203 * associated with its buffer, and will only referenced the buffer while 1204 * the node itself is referenced. 1205 * 1206 * A hammer_node can also be passively associated with other HAMMER 1207 * structures, such as inodes, while retaining 0 references. These 1208 * associations can be cleared backwards using a pointer-to-pointer in 1209 * the hammer_node. 1210 * 1211 * This allows the HAMMER implementation to cache hammer_nodes long-term 1212 * and short-cut a great deal of the infrastructure's complexity. In 1213 * most cases a cached node can be reacquired without having to dip into 1214 * either the buffer or cluster management code. 1215 * 1216 * The caller must pass a referenced cluster on call and will retain 1217 * ownership of the reference on return. The node will acquire its own 1218 * additional references, if necessary. 1219 */ 1220 hammer_node_t 1221 hammer_get_node(hammer_transaction_t trans, hammer_off_t node_offset, 1222 int isnew, int *errorp) 1223 { 1224 hammer_mount_t hmp = trans->hmp; 1225 hammer_node_t node; 1226 int doload; 1227 1228 KKASSERT((node_offset & HAMMER_OFF_ZONE_MASK) == HAMMER_ZONE_BTREE); 1229 1230 /* 1231 * Locate the structure, allocating one if necessary. 1232 */ 1233 again: 1234 node = RB_LOOKUP(hammer_nod_rb_tree, &hmp->rb_nods_root, node_offset); 1235 if (node == NULL) { 1236 ++hammer_count_nodes; 1237 node = kmalloc(sizeof(*node), hmp->m_misc, M_WAITOK|M_ZERO|M_USE_RESERVE); 1238 node->node_offset = node_offset; 1239 node->hmp = hmp; 1240 TAILQ_INIT(&node->cursor_list); 1241 TAILQ_INIT(&node->cache_list); 1242 if (RB_INSERT(hammer_nod_rb_tree, &hmp->rb_nods_root, node)) { 1243 --hammer_count_nodes; 1244 kfree(node, hmp->m_misc); 1245 goto again; 1246 } 1247 doload = hammer_ref_interlock_true(&node->lock); 1248 } else { 1249 doload = hammer_ref_interlock(&node->lock); 1250 } 1251 if (doload) { 1252 *errorp = hammer_load_node(trans, node, isnew); 1253 trans->flags |= HAMMER_TRANSF_DIDIO; 1254 if (*errorp) 1255 node = NULL; 1256 } else { 1257 KKASSERT(node->ondisk); 1258 *errorp = 0; 1259 hammer_io_advance(&node->buffer->io); 1260 } 1261 return(node); 1262 } 1263 1264 /* 1265 * Reference an already-referenced node. 0->1 transitions should assert 1266 * so we do not have to deal with hammer_ref() setting CHECK. 1267 */ 1268 void 1269 hammer_ref_node(hammer_node_t node) 1270 { 1271 KKASSERT(hammer_isactive(&node->lock) && node->ondisk != NULL); 1272 hammer_ref(&node->lock); 1273 } 1274 1275 /* 1276 * Load a node's on-disk data reference. Called with the node referenced 1277 * and interlocked. 1278 * 1279 * On return the node interlock will be unlocked. If a non-zero error code 1280 * is returned the node will also be dereferenced (and the caller's pointer 1281 * will be stale). 1282 */ 1283 static int 1284 hammer_load_node(hammer_transaction_t trans, hammer_node_t node, int isnew) 1285 { 1286 hammer_buffer_t buffer; 1287 hammer_off_t buf_offset; 1288 int error; 1289 1290 error = 0; 1291 if (node->ondisk == NULL) { 1292 /* 1293 * This is a little confusing but the jist is that 1294 * node->buffer determines whether the node is on 1295 * the buffer's clist and node->ondisk determines 1296 * whether the buffer is referenced. 1297 * 1298 * We could be racing a buffer release, in which case 1299 * node->buffer may become NULL while we are blocked 1300 * referencing the buffer. 1301 */ 1302 if ((buffer = node->buffer) != NULL) { 1303 error = hammer_ref_buffer(buffer); 1304 if (error == 0 && node->buffer == NULL) { 1305 TAILQ_INSERT_TAIL(&buffer->clist, 1306 node, entry); 1307 node->buffer = buffer; 1308 } 1309 } else { 1310 buf_offset = node->node_offset & ~HAMMER_BUFMASK64; 1311 buffer = hammer_get_buffer(node->hmp, buf_offset, 1312 HAMMER_BUFSIZE, 0, &error); 1313 if (buffer) { 1314 KKASSERT(error == 0); 1315 TAILQ_INSERT_TAIL(&buffer->clist, 1316 node, entry); 1317 node->buffer = buffer; 1318 } 1319 } 1320 if (error) 1321 goto failed; 1322 node->ondisk = (void *)((char *)buffer->ondisk + 1323 (node->node_offset & HAMMER_BUFMASK)); 1324 1325 /* 1326 * Check CRC. NOTE: Neither flag is set and the CRC is not 1327 * generated on new B-Tree nodes. 1328 */ 1329 if (isnew == 0 && 1330 (node->flags & HAMMER_NODE_CRCANY) == 0) { 1331 if (hammer_crc_test_btree(node->ondisk) == 0) { 1332 if (hammer_debug_critical) 1333 Debugger("CRC FAILED: B-TREE NODE"); 1334 node->flags |= HAMMER_NODE_CRCBAD; 1335 } else { 1336 node->flags |= HAMMER_NODE_CRCGOOD; 1337 } 1338 } 1339 } 1340 if (node->flags & HAMMER_NODE_CRCBAD) { 1341 if (trans->flags & HAMMER_TRANSF_CRCDOM) 1342 error = EDOM; 1343 else 1344 error = EIO; 1345 } 1346 failed: 1347 if (error) { 1348 _hammer_rel_node(node, 1); 1349 } else { 1350 hammer_ref_interlock_done(&node->lock); 1351 } 1352 return (error); 1353 } 1354 1355 /* 1356 * Safely reference a node, interlock against flushes via the IO subsystem. 1357 */ 1358 hammer_node_t 1359 hammer_ref_node_safe(hammer_transaction_t trans, hammer_node_cache_t cache, 1360 int *errorp) 1361 { 1362 hammer_node_t node; 1363 int doload; 1364 1365 node = cache->node; 1366 if (node != NULL) { 1367 doload = hammer_ref_interlock(&node->lock); 1368 if (doload) { 1369 *errorp = hammer_load_node(trans, node, 0); 1370 if (*errorp) 1371 node = NULL; 1372 } else { 1373 KKASSERT(node->ondisk); 1374 if (node->flags & HAMMER_NODE_CRCBAD) { 1375 if (trans->flags & HAMMER_TRANSF_CRCDOM) 1376 *errorp = EDOM; 1377 else 1378 *errorp = EIO; 1379 _hammer_rel_node(node, 0); 1380 node = NULL; 1381 } else { 1382 *errorp = 0; 1383 } 1384 } 1385 } else { 1386 *errorp = ENOENT; 1387 } 1388 return(node); 1389 } 1390 1391 /* 1392 * Release a hammer_node. On the last release the node dereferences 1393 * its underlying buffer and may or may not be destroyed. 1394 * 1395 * If locked is non-zero the passed node has been interlocked by the 1396 * caller and we are in the failure/unload path, otherwise it has not and 1397 * we are doing a normal release. 1398 * 1399 * This function will dispose of the interlock and the reference. 1400 * On return the node pointer is stale. 1401 */ 1402 void 1403 _hammer_rel_node(hammer_node_t node, int locked) 1404 { 1405 hammer_buffer_t buffer; 1406 1407 /* 1408 * Deref the node. If this isn't the 1->0 transition we're basically 1409 * done. If locked is non-zero this function will just deref the 1410 * locked node and return TRUE, otherwise it will deref the locked 1411 * node and either lock and return TRUE on the 1->0 transition or 1412 * not lock and return FALSE. 1413 */ 1414 if (hammer_rel_interlock(&node->lock, locked) == 0) 1415 return; 1416 1417 /* 1418 * Either locked was non-zero and we are interlocked, or the 1419 * hammer_rel_interlock() call returned non-zero and we are 1420 * interlocked. 1421 * 1422 * The ref-count must still be decremented if locked != 0 so 1423 * the cleanup required still varies a bit. 1424 * 1425 * hammer_flush_node() when called with 1 or 2 will dispose of 1426 * the lock and possible ref-count. 1427 */ 1428 if (node->ondisk == NULL) { 1429 hammer_flush_node(node, locked + 1); 1430 /* node is stale now */ 1431 return; 1432 } 1433 1434 /* 1435 * Do not disassociate the node from the buffer if it represents 1436 * a modified B-Tree node that still needs its crc to be generated. 1437 */ 1438 if (node->flags & HAMMER_NODE_NEEDSCRC) { 1439 hammer_rel_interlock_done(&node->lock, locked); 1440 return; 1441 } 1442 1443 /* 1444 * Do final cleanups and then either destroy the node and leave it 1445 * passively cached. The buffer reference is removed regardless. 1446 */ 1447 buffer = node->buffer; 1448 node->ondisk = NULL; 1449 1450 if ((node->flags & HAMMER_NODE_FLUSH) == 0) { 1451 /* 1452 * Normal release. 1453 */ 1454 hammer_rel_interlock_done(&node->lock, locked); 1455 } else { 1456 /* 1457 * Destroy the node. 1458 */ 1459 hammer_flush_node(node, locked + 1); 1460 /* node is stale */ 1461 1462 } 1463 hammer_rel_buffer(buffer, 0); 1464 } 1465 1466 void 1467 hammer_rel_node(hammer_node_t node) 1468 { 1469 _hammer_rel_node(node, 0); 1470 } 1471 1472 /* 1473 * Free space on-media associated with a B-Tree node. 1474 */ 1475 void 1476 hammer_delete_node(hammer_transaction_t trans, hammer_node_t node) 1477 { 1478 KKASSERT((node->flags & HAMMER_NODE_DELETED) == 0); 1479 node->flags |= HAMMER_NODE_DELETED; 1480 hammer_blockmap_free(trans, node->node_offset, sizeof(*node->ondisk)); 1481 } 1482 1483 /* 1484 * Passively cache a referenced hammer_node. The caller may release 1485 * the node on return. 1486 */ 1487 void 1488 hammer_cache_node(hammer_node_cache_t cache, hammer_node_t node) 1489 { 1490 /* 1491 * If the node doesn't exist, or is being deleted, don't cache it! 1492 * 1493 * The node can only ever be NULL in the I/O failure path. 1494 */ 1495 if (node == NULL || (node->flags & HAMMER_NODE_DELETED)) 1496 return; 1497 if (cache->node == node) 1498 return; 1499 while (cache->node) 1500 hammer_uncache_node(cache); 1501 if (node->flags & HAMMER_NODE_DELETED) 1502 return; 1503 cache->node = node; 1504 TAILQ_INSERT_TAIL(&node->cache_list, cache, entry); 1505 } 1506 1507 void 1508 hammer_uncache_node(hammer_node_cache_t cache) 1509 { 1510 hammer_node_t node; 1511 1512 if ((node = cache->node) != NULL) { 1513 TAILQ_REMOVE(&node->cache_list, cache, entry); 1514 cache->node = NULL; 1515 if (TAILQ_EMPTY(&node->cache_list)) 1516 hammer_flush_node(node, 0); 1517 } 1518 } 1519 1520 /* 1521 * Remove a node's cache references and destroy the node if it has no 1522 * other references or backing store. 1523 * 1524 * locked == 0 Normal unlocked operation 1525 * locked == 1 Call hammer_rel_interlock_done(..., 0); 1526 * locked == 2 Call hammer_rel_interlock_done(..., 1); 1527 * 1528 * XXX for now this isn't even close to being MPSAFE so the refs check 1529 * is sufficient. 1530 */ 1531 void 1532 hammer_flush_node(hammer_node_t node, int locked) 1533 { 1534 hammer_node_cache_t cache; 1535 hammer_buffer_t buffer; 1536 hammer_mount_t hmp = node->hmp; 1537 int dofree; 1538 1539 while ((cache = TAILQ_FIRST(&node->cache_list)) != NULL) { 1540 TAILQ_REMOVE(&node->cache_list, cache, entry); 1541 cache->node = NULL; 1542 } 1543 1544 /* 1545 * NOTE: refs is predisposed if another thread is blocking and 1546 * will be larger than 0 in that case. We aren't MPSAFE 1547 * here. 1548 */ 1549 if (node->ondisk == NULL && hammer_norefs(&node->lock)) { 1550 KKASSERT((node->flags & HAMMER_NODE_NEEDSCRC) == 0); 1551 RB_REMOVE(hammer_nod_rb_tree, &node->hmp->rb_nods_root, node); 1552 if ((buffer = node->buffer) != NULL) { 1553 node->buffer = NULL; 1554 TAILQ_REMOVE(&buffer->clist, node, entry); 1555 /* buffer is unreferenced because ondisk is NULL */ 1556 } 1557 dofree = 1; 1558 } else { 1559 dofree = 0; 1560 } 1561 1562 /* 1563 * Deal with the interlock if locked == 1 or locked == 2. 1564 */ 1565 if (locked) 1566 hammer_rel_interlock_done(&node->lock, locked - 1); 1567 1568 /* 1569 * Destroy if requested 1570 */ 1571 if (dofree) { 1572 --hammer_count_nodes; 1573 kfree(node, hmp->m_misc); 1574 } 1575 } 1576 1577 /* 1578 * Flush passively cached B-Tree nodes associated with this buffer. 1579 * This is only called when the buffer is about to be destroyed, so 1580 * none of the nodes should have any references. The buffer is locked. 1581 * 1582 * We may be interlocked with the buffer. 1583 */ 1584 void 1585 hammer_flush_buffer_nodes(hammer_buffer_t buffer) 1586 { 1587 hammer_node_t node; 1588 1589 while ((node = TAILQ_FIRST(&buffer->clist)) != NULL) { 1590 KKASSERT(node->ondisk == NULL); 1591 KKASSERT((node->flags & HAMMER_NODE_NEEDSCRC) == 0); 1592 1593 if (hammer_try_interlock_norefs(&node->lock)) { 1594 hammer_ref(&node->lock); 1595 node->flags |= HAMMER_NODE_FLUSH; 1596 _hammer_rel_node(node, 1); 1597 } else { 1598 KKASSERT(node->buffer != NULL); 1599 buffer = node->buffer; 1600 node->buffer = NULL; 1601 TAILQ_REMOVE(&buffer->clist, node, entry); 1602 /* buffer is unreferenced because ondisk is NULL */ 1603 } 1604 } 1605 } 1606 1607 1608 /************************************************************************ 1609 * ALLOCATORS * 1610 ************************************************************************/ 1611 1612 /* 1613 * Allocate a B-Tree node. 1614 */ 1615 hammer_node_t 1616 hammer_alloc_btree(hammer_transaction_t trans, hammer_off_t hint, int *errorp) 1617 { 1618 hammer_buffer_t buffer = NULL; 1619 hammer_node_t node = NULL; 1620 hammer_off_t node_offset; 1621 1622 node_offset = hammer_blockmap_alloc(trans, HAMMER_ZONE_BTREE_INDEX, 1623 sizeof(struct hammer_node_ondisk), 1624 hint, errorp); 1625 if (*errorp == 0) { 1626 node = hammer_get_node(trans, node_offset, 1, errorp); 1627 hammer_modify_node_noundo(trans, node); 1628 bzero(node->ondisk, sizeof(*node->ondisk)); 1629 hammer_modify_node_done(node); 1630 } 1631 if (buffer) 1632 hammer_rel_buffer(buffer, 0); 1633 return(node); 1634 } 1635 1636 /* 1637 * Allocate data. If the address of a data buffer is supplied then 1638 * any prior non-NULL *data_bufferp will be released and *data_bufferp 1639 * will be set to the related buffer. The caller must release it when 1640 * finally done. The initial *data_bufferp should be set to NULL by 1641 * the caller. 1642 * 1643 * The caller is responsible for making hammer_modify*() calls on the 1644 * *data_bufferp. 1645 */ 1646 void * 1647 hammer_alloc_data(hammer_transaction_t trans, int32_t data_len, 1648 u_int16_t rec_type, hammer_off_t *data_offsetp, 1649 struct hammer_buffer **data_bufferp, 1650 hammer_off_t hint, int *errorp) 1651 { 1652 void *data; 1653 int zone; 1654 1655 /* 1656 * Allocate data 1657 */ 1658 if (data_len) { 1659 switch(rec_type) { 1660 case HAMMER_RECTYPE_INODE: 1661 case HAMMER_RECTYPE_DIRENTRY: 1662 case HAMMER_RECTYPE_EXT: 1663 case HAMMER_RECTYPE_FIX: 1664 case HAMMER_RECTYPE_PFS: 1665 case HAMMER_RECTYPE_SNAPSHOT: 1666 case HAMMER_RECTYPE_CONFIG: 1667 zone = HAMMER_ZONE_META_INDEX; 1668 break; 1669 case HAMMER_RECTYPE_DATA: 1670 case HAMMER_RECTYPE_DB: 1671 if (data_len <= HAMMER_BUFSIZE / 2) { 1672 zone = HAMMER_ZONE_SMALL_DATA_INDEX; 1673 } else { 1674 data_len = (data_len + HAMMER_BUFMASK) & 1675 ~HAMMER_BUFMASK; 1676 zone = HAMMER_ZONE_LARGE_DATA_INDEX; 1677 } 1678 break; 1679 default: 1680 panic("hammer_alloc_data: rec_type %04x unknown", 1681 rec_type); 1682 zone = 0; /* NOT REACHED */ 1683 break; 1684 } 1685 *data_offsetp = hammer_blockmap_alloc(trans, zone, data_len, 1686 hint, errorp); 1687 } else { 1688 *data_offsetp = 0; 1689 } 1690 if (*errorp == 0 && data_bufferp) { 1691 if (data_len) { 1692 data = hammer_bread_ext(trans->hmp, *data_offsetp, 1693 data_len, errorp, data_bufferp); 1694 } else { 1695 data = NULL; 1696 } 1697 } else { 1698 data = NULL; 1699 } 1700 return(data); 1701 } 1702 1703 /* 1704 * Sync dirty buffers to the media and clean-up any loose ends. 1705 * 1706 * These functions do not start the flusher going, they simply 1707 * queue everything up to the flusher. 1708 */ 1709 static int hammer_sync_scan2(struct mount *mp, struct vnode *vp, void *data); 1710 1711 int 1712 hammer_queue_inodes_flusher(hammer_mount_t hmp, int waitfor) 1713 { 1714 struct hammer_sync_info info; 1715 1716 info.error = 0; 1717 info.waitfor = waitfor; 1718 if (waitfor == MNT_WAIT) { 1719 vsyncscan(hmp->mp, VMSC_GETVP | VMSC_ONEPASS, 1720 hammer_sync_scan2, &info); 1721 } else { 1722 vsyncscan(hmp->mp, VMSC_GETVP | VMSC_ONEPASS | VMSC_NOWAIT, 1723 hammer_sync_scan2, &info); 1724 } 1725 return(info.error); 1726 } 1727 1728 /* 1729 * Filesystem sync. If doing a synchronous sync make a second pass on 1730 * the vnodes in case any were already flushing during the first pass, 1731 * and activate the flusher twice (the second time brings the UNDO FIFO's 1732 * start position up to the end position after the first call). 1733 * 1734 * If doing a lazy sync make just one pass on the vnode list, ignoring 1735 * any new vnodes added to the list while the sync is in progress. 1736 */ 1737 int 1738 hammer_sync_hmp(hammer_mount_t hmp, int waitfor) 1739 { 1740 struct hammer_sync_info info; 1741 int flags; 1742 1743 flags = VMSC_GETVP; 1744 if (waitfor & MNT_LAZY) 1745 flags |= VMSC_ONEPASS; 1746 1747 info.error = 0; 1748 info.waitfor = MNT_NOWAIT; 1749 vsyncscan(hmp->mp, flags | VMSC_NOWAIT, hammer_sync_scan2, &info); 1750 1751 if (info.error == 0 && (waitfor & MNT_WAIT)) { 1752 info.waitfor = waitfor; 1753 vsyncscan(hmp->mp, flags, hammer_sync_scan2, &info); 1754 } 1755 if (waitfor == MNT_WAIT) { 1756 hammer_flusher_sync(hmp); 1757 hammer_flusher_sync(hmp); 1758 } else { 1759 hammer_flusher_async(hmp, NULL); 1760 hammer_flusher_async(hmp, NULL); 1761 } 1762 return(info.error); 1763 } 1764 1765 static int 1766 hammer_sync_scan2(struct mount *mp, struct vnode *vp, void *data) 1767 { 1768 struct hammer_sync_info *info = data; 1769 struct hammer_inode *ip; 1770 int error; 1771 1772 ip = VTOI(vp); 1773 if (ip == NULL) 1774 return(0); 1775 if (vp->v_type == VNON || vp->v_type == VBAD) { 1776 vclrisdirty(vp); 1777 return(0); 1778 } 1779 if ((ip->flags & HAMMER_INODE_MODMASK) == 0 && 1780 RB_EMPTY(&vp->v_rbdirty_tree)) { 1781 vclrisdirty(vp); 1782 return(0); 1783 } 1784 error = VOP_FSYNC(vp, MNT_NOWAIT, 0); 1785 if (error) 1786 info->error = error; 1787 return(0); 1788 } 1789