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 <sys/nlookup.h> 43 #include <sys/buf2.h> 44 45 #include "hammer.h" 46 47 static void hammer_free_volume(hammer_volume_t volume); 48 static int hammer_load_volume(hammer_volume_t volume); 49 static int hammer_load_buffer(hammer_buffer_t buffer, int isnew); 50 static int hammer_load_node(hammer_transaction_t trans, 51 hammer_node_t node, int isnew); 52 static void _hammer_rel_node(hammer_node_t node, int locked); 53 54 static int 55 hammer_vol_rb_compare(hammer_volume_t vol1, hammer_volume_t vol2) 56 { 57 if (vol1->vol_no < vol2->vol_no) 58 return(-1); 59 if (vol1->vol_no > vol2->vol_no) 60 return(1); 61 return(0); 62 } 63 64 /* 65 * hammer_buffer structures are indexed via their zoneX_offset, not 66 * their zone2_offset. 67 */ 68 static int 69 hammer_buf_rb_compare(hammer_buffer_t buf1, hammer_buffer_t buf2) 70 { 71 if (buf1->zoneX_offset < buf2->zoneX_offset) 72 return(-1); 73 if (buf1->zoneX_offset > buf2->zoneX_offset) 74 return(1); 75 return(0); 76 } 77 78 static int 79 hammer_nod_rb_compare(hammer_node_t node1, hammer_node_t node2) 80 { 81 if (node1->node_offset < node2->node_offset) 82 return(-1); 83 if (node1->node_offset > node2->node_offset) 84 return(1); 85 return(0); 86 } 87 88 RB_GENERATE2(hammer_vol_rb_tree, hammer_volume, rb_node, 89 hammer_vol_rb_compare, int32_t, vol_no); 90 RB_GENERATE2(hammer_buf_rb_tree, hammer_buffer, rb_node, 91 hammer_buf_rb_compare, hammer_off_t, zoneX_offset); 92 RB_GENERATE2(hammer_nod_rb_tree, hammer_node, rb_node, 93 hammer_nod_rb_compare, hammer_off_t, node_offset); 94 95 /************************************************************************ 96 * VOLUMES * 97 ************************************************************************ 98 * 99 * Load a HAMMER volume by name. Returns 0 on success or a positive error 100 * code on failure. Volumes must be loaded at mount time or via hammer 101 * volume-add command, hammer_get_volume() will not load a new volume. 102 * 103 * The passed devvp is vref()'d but not locked. This function consumes the 104 * ref (typically by associating it with the volume structure). 105 * 106 * Calls made to hammer_load_volume() or single-threaded 107 */ 108 int 109 hammer_install_volume(hammer_mount_t hmp, const char *volname, 110 struct vnode *devvp, void *data) 111 { 112 struct mount *mp; 113 hammer_volume_t volume; 114 hammer_volume_ondisk_t ondisk; 115 hammer_volume_ondisk_t img; 116 struct nlookupdata nd; 117 struct buf *bp = NULL; 118 int error; 119 int ronly; 120 int setmp = 0; 121 int i; 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_IOTYPE_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; 184 185 /* 186 * Initialize the volume header with data if the data is specified. 187 */ 188 if (ronly == 0 && data) { 189 img = (hammer_volume_ondisk_t)data; 190 if (ondisk->vol_signature == HAMMER_FSBUF_VOLUME) { 191 hkprintf("Formatting of valid HAMMER volume %s denied. " 192 "Erase with hammer strip or dd!\n", volname); 193 error = EFTYPE; 194 goto late_failure; 195 } 196 bcopy(img, ondisk, sizeof(*img)); 197 } 198 199 if (ondisk->vol_signature != HAMMER_FSBUF_VOLUME) { 200 hkprintf("volume %s has an invalid header\n", volume->vol_name); 201 for (i = 0; i < (int)sizeof(ondisk->vol_signature); i++) { 202 kprintf("%02x", ((char*)&ondisk->vol_signature)[i] & 0xFF); 203 if (i != (int)sizeof(ondisk->vol_signature) - 1) 204 kprintf(" "); 205 } 206 kprintf("\n"); 207 error = EFTYPE; 208 goto late_failure; 209 } 210 volume->vol_no = ondisk->vol_no; 211 volume->vol_flags = ondisk->vol_flags; 212 volume->maxbuf_off = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 213 HAMMER_VOL_BUF_SIZE(ondisk)); 214 215 if (RB_EMPTY(&hmp->rb_vols_root)) { 216 hmp->fsid = ondisk->vol_fsid; 217 } else if (kuuid_compare(&hmp->fsid, &ondisk->vol_fsid)) { 218 hkprintf("volume %s's fsid does not match other volumes\n", 219 volume->vol_name); 220 error = EFTYPE; 221 goto late_failure; 222 } 223 224 /* 225 * Insert the volume structure into the red-black tree. 226 */ 227 if (RB_INSERT(hammer_vol_rb_tree, &hmp->rb_vols_root, volume)) { 228 hkprintf("volume %s has a duplicate vol_no %d\n", 229 volume->vol_name, volume->vol_no); 230 error = EEXIST; 231 } 232 233 if (error == 0) 234 hammer_volume_number_add(hmp, volume); 235 236 /* 237 * Set the root volume . HAMMER special cases rootvol the structure. 238 * We do not hold a ref because this would prevent related I/O 239 * from being flushed. 240 */ 241 if (error == 0 && ondisk->vol_rootvol == ondisk->vol_no) { 242 if (ondisk->vol_rootvol != HAMMER_ROOT_VOLNO) { 243 hkprintf("volume %s has invalid root vol_no %d\n", 244 volume->vol_name, ondisk->vol_rootvol); 245 error = EINVAL; 246 goto late_failure; 247 } 248 hmp->rootvol = volume; 249 hmp->nvolumes = ondisk->vol_count; 250 if (bp) { 251 brelse(bp); 252 bp = NULL; 253 } 254 hmp->mp->mnt_stat.f_blocks += ondisk->vol0_stat_bigblocks * 255 HAMMER_BUFFERS_PER_BIGBLOCK; 256 hmp->mp->mnt_vstat.f_blocks += ondisk->vol0_stat_bigblocks * 257 HAMMER_BUFFERS_PER_BIGBLOCK; 258 } 259 late_failure: 260 if (bp) 261 brelse(bp); 262 if (error) { 263 /*vinvalbuf(volume->devvp, V_SAVE, 0, 0);*/ 264 if (setmp) 265 volume->devvp->v_rdev->si_mountpoint = NULL; 266 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 267 VOP_CLOSE(volume->devvp, ronly ? FREAD : FREAD|FWRITE, NULL); 268 vn_unlock(volume->devvp); 269 hammer_free_volume(volume); 270 } 271 return (error); 272 } 273 274 /* 275 * This is called for each volume when updating the mount point from 276 * read-write to read-only or vise-versa. 277 */ 278 int 279 hammer_adjust_volume_mode(hammer_volume_t volume, void *data __unused) 280 { 281 if (volume->devvp) { 282 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 283 if (volume->io.hmp->ronly) { 284 /* do not call vinvalbuf */ 285 VOP_OPEN(volume->devvp, FREAD, FSCRED, NULL); 286 VOP_CLOSE(volume->devvp, FREAD|FWRITE, NULL); 287 } else { 288 /* do not call vinvalbuf */ 289 VOP_OPEN(volume->devvp, FREAD|FWRITE, FSCRED, NULL); 290 VOP_CLOSE(volume->devvp, FREAD, NULL); 291 } 292 vn_unlock(volume->devvp); 293 } 294 return(0); 295 } 296 297 /* 298 * Unload and free a HAMMER volume. Must return >= 0 to continue scan 299 * so returns -1 on failure. 300 */ 301 int 302 hammer_unload_volume(hammer_volume_t volume, void *data) 303 { 304 hammer_mount_t hmp = volume->io.hmp; 305 struct buf *bp = NULL; 306 hammer_volume_ondisk_t img; 307 int ronly = ((hmp->mp->mnt_flag & MNT_RDONLY) ? 1 : 0); 308 int error; 309 310 /* 311 * Clear the volume header with data if the data is specified. 312 */ 313 if (ronly == 0 && data && volume->devvp) { 314 img = (hammer_volume_ondisk_t)data; 315 error = bread(volume->devvp, 0LL, HAMMER_BUFSIZE, &bp); 316 if (error || bp->b_bcount < sizeof(*img)) { 317 hmkprintf(hmp, "Failed to read volume header: %d\n", error); 318 brelse(bp); 319 } else { 320 bcopy(img, bp->b_data, sizeof(*img)); 321 error = bwrite(bp); 322 if (error) 323 hmkprintf(hmp, "Failed to clear volume header: %d\n", 324 error); 325 } 326 } 327 328 /* 329 * Clean up the root volume pointer, which is held unlocked in hmp. 330 */ 331 if (hmp->rootvol == volume) 332 hmp->rootvol = NULL; 333 334 /* 335 * We must not flush a dirty buffer to disk on umount. It should 336 * have already been dealt with by the flusher, or we may be in 337 * catastrophic failure. 338 */ 339 hammer_io_clear_modify(&volume->io, 1); 340 volume->io.waitdep = 1; 341 342 /* 343 * Clean up the persistent ref ioerror might have on the volume 344 */ 345 if (volume->io.ioerror) 346 hammer_io_clear_error_noassert(&volume->io); 347 348 /* 349 * This should release the bp. Releasing the volume with flush set 350 * implies the interlock is set. 351 */ 352 hammer_ref_interlock_true(&volume->io.lock); 353 hammer_rel_volume(volume, 1); 354 KKASSERT(volume->io.bp == NULL); 355 356 /* 357 * There should be no references on the volume. 358 */ 359 KKASSERT(hammer_norefs(&volume->io.lock)); 360 361 volume->ondisk = NULL; 362 if (volume->devvp) { 363 if (volume->devvp->v_rdev && 364 volume->devvp->v_rdev->si_mountpoint == hmp->mp) { 365 volume->devvp->v_rdev->si_mountpoint = NULL; 366 } 367 if (ronly) { 368 /* 369 * Make sure we don't sync anything to disk if we 370 * are in read-only mode (1) or critically-errored 371 * (2). Note that there may be dirty buffers in 372 * normal read-only mode from crash recovery. 373 */ 374 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 375 vinvalbuf(volume->devvp, 0, 0, 0); 376 VOP_CLOSE(volume->devvp, FREAD, NULL); 377 vn_unlock(volume->devvp); 378 } else { 379 /* 380 * Normal termination, save any dirty buffers 381 * (XXX there really shouldn't be any). 382 */ 383 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 384 vinvalbuf(volume->devvp, V_SAVE, 0, 0); 385 VOP_CLOSE(volume->devvp, FREAD|FWRITE, NULL); 386 vn_unlock(volume->devvp); 387 } 388 } 389 390 /* 391 * Destroy the structure 392 */ 393 RB_REMOVE(hammer_vol_rb_tree, &hmp->rb_vols_root, volume); 394 hammer_volume_number_del(hmp, volume); 395 hammer_free_volume(volume); 396 return(0); 397 } 398 399 static 400 void 401 hammer_free_volume(hammer_volume_t volume) 402 { 403 hammer_mount_t hmp = volume->io.hmp; 404 405 if (volume->vol_name) { 406 kfree(volume->vol_name, hmp->m_misc); 407 volume->vol_name = NULL; 408 } 409 if (volume->devvp) { 410 vrele(volume->devvp); 411 volume->devvp = NULL; 412 } 413 --hammer_count_volumes; 414 kfree(volume, hmp->m_misc); 415 } 416 417 /* 418 * Get a HAMMER volume. The volume must already exist. 419 */ 420 hammer_volume_t 421 hammer_get_volume(hammer_mount_t hmp, int32_t vol_no, int *errorp) 422 { 423 hammer_volume_t volume; 424 425 /* 426 * Locate the volume structure 427 */ 428 volume = RB_LOOKUP(hammer_vol_rb_tree, &hmp->rb_vols_root, vol_no); 429 if (volume == NULL) { 430 *errorp = ENOENT; 431 return(NULL); 432 } 433 434 /* 435 * Reference the volume, load/check the data on the 0->1 transition. 436 * hammer_load_volume() will dispose of the interlock on return, 437 * and also clean up the ref count on error. 438 */ 439 if (hammer_ref_interlock(&volume->io.lock)) { 440 *errorp = hammer_load_volume(volume); 441 if (*errorp) 442 volume = NULL; 443 } else { 444 KKASSERT(volume->ondisk); 445 *errorp = 0; 446 } 447 return(volume); 448 } 449 450 int 451 hammer_ref_volume(hammer_volume_t volume) 452 { 453 int error; 454 455 /* 456 * Reference the volume and deal with the check condition used to 457 * load its ondisk info. 458 */ 459 if (hammer_ref_interlock(&volume->io.lock)) { 460 error = hammer_load_volume(volume); 461 } else { 462 KKASSERT(volume->ondisk); 463 error = 0; 464 } 465 return (error); 466 } 467 468 /* 469 * May be called without fs_token 470 */ 471 hammer_volume_t 472 hammer_get_root_volume(hammer_mount_t hmp, int *errorp) 473 { 474 hammer_volume_t volume; 475 476 volume = hmp->rootvol; 477 KKASSERT(volume != NULL); 478 479 /* 480 * Reference the volume and deal with the check condition used to 481 * load its ondisk info. 482 */ 483 if (hammer_ref_interlock(&volume->io.lock)) { 484 lwkt_gettoken(&volume->io.hmp->fs_token); 485 *errorp = hammer_load_volume(volume); 486 lwkt_reltoken(&volume->io.hmp->fs_token); 487 if (*errorp) 488 volume = NULL; 489 } else { 490 KKASSERT(volume->ondisk); 491 *errorp = 0; 492 } 493 return (volume); 494 } 495 496 /* 497 * Load a volume's on-disk information. The volume must be referenced and 498 * the interlock is held on call. The interlock will be released on return. 499 * The reference will also be released on return if an error occurs. 500 */ 501 static int 502 hammer_load_volume(hammer_volume_t volume) 503 { 504 int error; 505 506 if (volume->ondisk == NULL) { 507 error = hammer_io_read(volume->devvp, &volume->io, 508 HAMMER_BUFSIZE); 509 if (error == 0) { 510 volume->ondisk = (void *)volume->io.bp->b_data; 511 hammer_ref_interlock_done(&volume->io.lock); 512 } else { 513 hammer_rel_volume(volume, 1); 514 } 515 } else { 516 error = 0; 517 } 518 return(error); 519 } 520 521 /* 522 * Release a previously acquired reference on the volume. 523 * 524 * Volumes are not unloaded from memory during normal operation. 525 * 526 * May be called without fs_token 527 */ 528 void 529 hammer_rel_volume(hammer_volume_t volume, int locked) 530 { 531 struct buf *bp; 532 533 if (hammer_rel_interlock(&volume->io.lock, locked)) { 534 lwkt_gettoken(&volume->io.hmp->fs_token); 535 volume->ondisk = NULL; 536 bp = hammer_io_release(&volume->io, locked); 537 lwkt_reltoken(&volume->io.hmp->fs_token); 538 hammer_rel_interlock_done(&volume->io.lock, locked); 539 if (bp) 540 brelse(bp); 541 } 542 } 543 544 int 545 hammer_mountcheck_volumes(hammer_mount_t hmp) 546 { 547 hammer_volume_t vol; 548 int i; 549 550 HAMMER_VOLUME_NUMBER_FOREACH(hmp, i) { 551 vol = RB_LOOKUP(hammer_vol_rb_tree, &hmp->rb_vols_root, i); 552 if (vol == NULL) 553 return(EINVAL); 554 } 555 return(0); 556 } 557 558 int 559 hammer_get_installed_volumes(hammer_mount_t hmp) 560 { 561 int i, ret = 0; 562 563 HAMMER_VOLUME_NUMBER_FOREACH(hmp, i) 564 ret++; 565 return(ret); 566 } 567 568 /************************************************************************ 569 * BUFFERS * 570 ************************************************************************ 571 * 572 * Manage buffers. Currently most blockmap-backed zones are direct-mapped 573 * to zone-2 buffer offsets, without a translation stage. However, the 574 * hammer_buffer structure is indexed by its zoneX_offset, not its 575 * zone2_offset. 576 * 577 * The proper zone must be maintained throughout the code-base all the way 578 * through to the big-block allocator, or routines like hammer_del_buffers() 579 * will not be able to locate all potentially conflicting buffers. 580 */ 581 582 /* 583 * Helper function returns whether a zone offset can be directly translated 584 * to a raw buffer index or not. Really only the volume and undo zones 585 * can't be directly translated. Volumes are special-cased and undo zones 586 * shouldn't be aliased accessed in read-only mode. 587 * 588 * This function is ONLY used to detect aliased zones during a read-only 589 * mount. 590 */ 591 static __inline int 592 hammer_direct_zone(hammer_off_t buf_offset) 593 { 594 return(hammer_is_zone_direct_xlated(buf_offset)); 595 } 596 597 hammer_buffer_t 598 hammer_get_buffer(hammer_mount_t hmp, hammer_off_t buf_offset, 599 int bytes, int isnew, int *errorp) 600 { 601 hammer_buffer_t buffer; 602 hammer_volume_t volume; 603 hammer_off_t zone2_offset; 604 int vol_no; 605 int zone; 606 607 buf_offset &= ~HAMMER_BUFMASK64; 608 again: 609 /* 610 * Shortcut if the buffer is already cached 611 */ 612 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, buf_offset); 613 if (buffer) { 614 /* 615 * Once refed the ondisk field will not be cleared by 616 * any other action. Shortcut the operation if the 617 * ondisk structure is valid. 618 */ 619 found_aliased: 620 if (hammer_ref_interlock(&buffer->io.lock) == 0) { 621 hammer_io_advance(&buffer->io); 622 KKASSERT(buffer->ondisk); 623 *errorp = 0; 624 return(buffer); 625 } 626 627 /* 628 * 0->1 transition or defered 0->1 transition (CHECK), 629 * interlock now held. Shortcut if ondisk is already 630 * assigned. 631 */ 632 atomic_add_int(&hammer_count_refedbufs, 1); 633 if (buffer->ondisk) { 634 hammer_io_advance(&buffer->io); 635 hammer_ref_interlock_done(&buffer->io.lock); 636 *errorp = 0; 637 return(buffer); 638 } 639 640 /* 641 * The buffer is no longer loose if it has a ref, and 642 * cannot become loose once it gains a ref. Loose 643 * buffers will never be in a modified state. This should 644 * only occur on the 0->1 transition of refs. 645 * 646 * lose_root can be modified via a biodone() interrupt 647 * so the io_token must be held. 648 */ 649 if (buffer->io.mod_root == &hmp->lose_root) { 650 lwkt_gettoken(&hmp->io_token); 651 if (buffer->io.mod_root == &hmp->lose_root) { 652 RB_REMOVE(hammer_mod_rb_tree, 653 buffer->io.mod_root, &buffer->io); 654 buffer->io.mod_root = NULL; 655 KKASSERT(buffer->io.modified == 0); 656 } 657 lwkt_reltoken(&hmp->io_token); 658 } 659 goto found; 660 } else if (hmp->ronly && hammer_direct_zone(buf_offset)) { 661 /* 662 * If this is a read-only mount there could be an alias 663 * in the raw-zone. If there is we use that buffer instead. 664 * 665 * rw mounts will not have aliases. Also note when going 666 * from ro -> rw the recovered raw buffers are flushed and 667 * reclaimed, so again there will not be any aliases once 668 * the mount is rw. 669 */ 670 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 671 hammer_xlate_to_zone2(buf_offset)); 672 if (buffer) { 673 if (hammer_debug_general & 0x0001) { 674 hkrateprintf(&hmp->kdiag, 675 "recovered aliased %016jx\n", 676 (intmax_t)buf_offset); 677 } 678 goto found_aliased; 679 } 680 } 681 682 /* 683 * Handle blockmap offset translations 684 */ 685 zone = HAMMER_ZONE_DECODE(buf_offset); 686 if (hammer_is_index_record(zone)) { 687 zone2_offset = hammer_blockmap_lookup(hmp, buf_offset, errorp); 688 } else if (zone == HAMMER_ZONE_UNDO_INDEX) { 689 zone2_offset = hammer_undo_lookup(hmp, buf_offset, errorp); 690 } else { 691 /* Must be zone-2 (not 1 or 4 or 15) */ 692 KKASSERT(zone == HAMMER_ZONE_RAW_BUFFER_INDEX); 693 zone2_offset = buf_offset; 694 *errorp = 0; 695 } 696 if (*errorp) 697 return(NULL); 698 699 /* 700 * NOTE: zone2_offset and maxbuf_off are both full zone-2 offset 701 * specifications. 702 */ 703 KKASSERT(hammer_is_zone_raw_buffer(zone2_offset)); 704 vol_no = HAMMER_VOL_DECODE(zone2_offset); 705 volume = hammer_get_volume(hmp, vol_no, errorp); 706 if (volume == NULL) 707 return(NULL); 708 709 KKASSERT(zone2_offset < volume->maxbuf_off); 710 711 /* 712 * Allocate a new buffer structure. We will check for races later. 713 */ 714 ++hammer_count_buffers; 715 buffer = kmalloc(sizeof(*buffer), hmp->m_misc, 716 M_WAITOK|M_ZERO|M_USE_RESERVE); 717 buffer->zone2_offset = zone2_offset; 718 buffer->zoneX_offset = buf_offset; 719 720 hammer_io_init(&buffer->io, volume, hammer_zone_to_iotype(zone)); 721 buffer->io.offset = hammer_xlate_to_phys(volume->ondisk, zone2_offset); 722 buffer->io.bytes = bytes; 723 TAILQ_INIT(&buffer->node_list); 724 hammer_ref_interlock_true(&buffer->io.lock); 725 726 /* 727 * Insert the buffer into the RB tree and handle late collisions. 728 */ 729 if (RB_INSERT(hammer_buf_rb_tree, &hmp->rb_bufs_root, buffer)) { 730 hammer_rel_volume(volume, 0); 731 buffer->io.volume = NULL; /* safety */ 732 if (hammer_rel_interlock(&buffer->io.lock, 1)) /* safety */ 733 hammer_rel_interlock_done(&buffer->io.lock, 1); 734 --hammer_count_buffers; 735 kfree(buffer, hmp->m_misc); 736 goto again; 737 } 738 atomic_add_int(&hammer_count_refedbufs, 1); 739 found: 740 741 /* 742 * The buffer is referenced and interlocked. Load the buffer 743 * if necessary. hammer_load_buffer() deals with the interlock 744 * and, if an error is returned, also deals with the ref. 745 */ 746 if (buffer->ondisk == NULL) { 747 *errorp = hammer_load_buffer(buffer, isnew); 748 if (*errorp) 749 buffer = NULL; 750 } else { 751 hammer_io_advance(&buffer->io); 752 hammer_ref_interlock_done(&buffer->io.lock); 753 *errorp = 0; 754 } 755 return(buffer); 756 } 757 758 /* 759 * This is used by the direct-read code to deal with large-data buffers 760 * created by the reblocker and mirror-write code. The direct-read code 761 * bypasses the HAMMER buffer subsystem and so any aliased dirty or write- 762 * running hammer buffers must be fully synced to disk before we can issue 763 * the direct-read. 764 * 765 * This code path is not considered critical as only the rebocker and 766 * mirror-write code will create large-data buffers via the HAMMER buffer 767 * subsystem. They do that because they operate at the B-Tree level and 768 * do not access the vnode/inode structures. 769 */ 770 void 771 hammer_sync_buffers(hammer_mount_t hmp, hammer_off_t base_offset, int bytes) 772 { 773 hammer_buffer_t buffer; 774 int error; 775 776 KKASSERT(hammer_is_zone_large_data(base_offset)); 777 778 while (bytes > 0) { 779 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 780 base_offset); 781 if (buffer && (buffer->io.modified || buffer->io.running)) { 782 error = hammer_ref_buffer(buffer); 783 if (error == 0) { 784 hammer_io_wait(&buffer->io); 785 if (buffer->io.modified) { 786 hammer_io_write_interlock(&buffer->io); 787 hammer_io_flush(&buffer->io, 0); 788 hammer_io_done_interlock(&buffer->io); 789 hammer_io_wait(&buffer->io); 790 } 791 hammer_rel_buffer(buffer, 0); 792 } 793 } 794 base_offset += HAMMER_BUFSIZE; 795 bytes -= HAMMER_BUFSIZE; 796 } 797 } 798 799 /* 800 * Destroy all buffers covering the specified zoneX offset range. This 801 * is called when the related blockmap layer2 entry is freed or when 802 * a direct write bypasses our buffer/buffer-cache subsystem. 803 * 804 * The buffers may be referenced by the caller itself. Setting reclaim 805 * will cause the buffer to be destroyed when it's ref count reaches zero. 806 * 807 * Return 0 on success, EAGAIN if some buffers could not be destroyed due 808 * to additional references held by other threads, or some other (typically 809 * fatal) error. 810 */ 811 int 812 hammer_del_buffers(hammer_mount_t hmp, hammer_off_t base_offset, 813 hammer_off_t zone2_offset, int bytes, 814 int report_conflicts) 815 { 816 hammer_buffer_t buffer; 817 hammer_volume_t volume; 818 int vol_no; 819 int error; 820 int ret_error; 821 822 vol_no = HAMMER_VOL_DECODE(zone2_offset); 823 volume = hammer_get_volume(hmp, vol_no, &ret_error); 824 KKASSERT(ret_error == 0); 825 826 while (bytes > 0) { 827 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 828 base_offset); 829 if (buffer) { 830 error = hammer_ref_buffer(buffer); 831 if (hammer_debug_general & 0x20000) { 832 hkprintf("delbufr %016jx rerr=%d 1ref=%d\n", 833 (intmax_t)buffer->zoneX_offset, 834 error, 835 hammer_oneref(&buffer->io.lock)); 836 } 837 if (error == 0 && !hammer_oneref(&buffer->io.lock)) { 838 error = EAGAIN; 839 hammer_rel_buffer(buffer, 0); 840 } 841 if (error == 0) { 842 KKASSERT(buffer->zone2_offset == zone2_offset); 843 hammer_io_clear_modify(&buffer->io, 1); 844 buffer->io.reclaim = 1; 845 buffer->io.waitdep = 1; 846 KKASSERT(buffer->io.volume == volume); 847 hammer_rel_buffer(buffer, 0); 848 } 849 } else { 850 error = hammer_io_inval(volume, zone2_offset); 851 } 852 if (error) { 853 ret_error = error; 854 if (report_conflicts || 855 (hammer_debug_general & 0x8000)) { 856 krateprintf(&hmp->kdiag, 857 "hammer_del_buffers: unable to " 858 "invalidate %016jx buffer=%p " 859 "rep=%d lkrefs=%08x\n", 860 (intmax_t)base_offset, 861 buffer, report_conflicts, 862 (buffer ? buffer->io.lock.refs : -1)); 863 } 864 } 865 base_offset += HAMMER_BUFSIZE; 866 zone2_offset += HAMMER_BUFSIZE; 867 bytes -= HAMMER_BUFSIZE; 868 } 869 hammer_rel_volume(volume, 0); 870 return (ret_error); 871 } 872 873 /* 874 * Given a referenced and interlocked buffer load/validate the data. 875 * 876 * The buffer interlock will be released on return. If an error is 877 * returned the buffer reference will also be released (and the buffer 878 * pointer will thus be stale). 879 */ 880 static int 881 hammer_load_buffer(hammer_buffer_t buffer, int isnew) 882 { 883 hammer_volume_t volume; 884 int error; 885 886 /* 887 * Load the buffer's on-disk info 888 */ 889 volume = buffer->io.volume; 890 891 if (hammer_debug_io & 0x0004) { 892 hdkprintf("load_buffer %016jx %016jx isnew=%d od=%p\n", 893 (intmax_t)buffer->zoneX_offset, 894 (intmax_t)buffer->zone2_offset, 895 isnew, buffer->ondisk); 896 } 897 898 if (buffer->ondisk == NULL) { 899 /* 900 * Issue the read or generate a new buffer. When reading 901 * the limit argument controls any read-ahead clustering 902 * hammer_io_read() is allowed to do. 903 * 904 * We cannot read-ahead in the large-data zone and we cannot 905 * cross a big-block boundary as the next big-block might 906 * use a different buffer size. 907 */ 908 if (isnew) { 909 error = hammer_io_new(volume->devvp, &buffer->io); 910 } else if (hammer_is_zone_large_data(buffer->zoneX_offset)) { 911 error = hammer_io_read(volume->devvp, &buffer->io, 912 buffer->io.bytes); 913 } else { 914 hammer_off_t limit; 915 916 limit = HAMMER_BIGBLOCK_DOALIGN(buffer->zone2_offset); 917 limit -= buffer->zone2_offset; 918 error = hammer_io_read(volume->devvp, &buffer->io, 919 limit); 920 } 921 if (error == 0) 922 buffer->ondisk = (void *)buffer->io.bp->b_data; 923 } else if (isnew) { 924 error = hammer_io_new(volume->devvp, &buffer->io); 925 } else { 926 error = 0; 927 } 928 if (error == 0) { 929 hammer_io_advance(&buffer->io); 930 hammer_ref_interlock_done(&buffer->io.lock); 931 } else { 932 hammer_rel_buffer(buffer, 1); 933 } 934 return (error); 935 } 936 937 /* 938 * NOTE: Called from RB_SCAN, must return >= 0 for scan to continue. 939 * This routine is only called during unmount or when a volume is 940 * removed. 941 * 942 * If data != NULL, it specifies a volume whoose buffers should 943 * be unloaded. 944 */ 945 int 946 hammer_unload_buffer(hammer_buffer_t buffer, void *data) 947 { 948 hammer_volume_t volume = (hammer_volume_t)data; 949 950 /* 951 * If volume != NULL we are only interested in unloading buffers 952 * associated with a particular volume. 953 */ 954 if (volume != NULL && volume != buffer->io.volume) 955 return 0; 956 957 /* 958 * Clean up the persistent ref ioerror might have on the buffer 959 * and acquire a ref. Expect a 0->1 transition. 960 */ 961 if (buffer->io.ioerror) { 962 hammer_io_clear_error_noassert(&buffer->io); 963 atomic_add_int(&hammer_count_refedbufs, -1); 964 } 965 hammer_ref_interlock_true(&buffer->io.lock); 966 atomic_add_int(&hammer_count_refedbufs, 1); 967 968 /* 969 * We must not flush a dirty buffer to disk on umount. It should 970 * have already been dealt with by the flusher, or we may be in 971 * catastrophic failure. 972 * 973 * We must set waitdep to ensure that a running buffer is waited 974 * on and released prior to us trying to unload the volume. 975 */ 976 hammer_io_clear_modify(&buffer->io, 1); 977 hammer_flush_buffer_nodes(buffer); 978 buffer->io.waitdep = 1; 979 hammer_rel_buffer(buffer, 1); 980 return(0); 981 } 982 983 /* 984 * Reference a buffer that is either already referenced or via a specially 985 * handled pointer (aka cursor->buffer). 986 */ 987 int 988 hammer_ref_buffer(hammer_buffer_t buffer) 989 { 990 hammer_mount_t hmp; 991 int error; 992 int locked; 993 994 /* 995 * Acquire a ref, plus the buffer will be interlocked on the 996 * 0->1 transition. 997 */ 998 locked = hammer_ref_interlock(&buffer->io.lock); 999 hmp = buffer->io.hmp; 1000 1001 /* 1002 * At this point a biodone() will not touch the buffer other then 1003 * incidental bits. However, lose_root can be modified via 1004 * a biodone() interrupt. 1005 * 1006 * No longer loose. lose_root requires the io_token. 1007 */ 1008 if (buffer->io.mod_root == &hmp->lose_root) { 1009 lwkt_gettoken(&hmp->io_token); 1010 if (buffer->io.mod_root == &hmp->lose_root) { 1011 RB_REMOVE(hammer_mod_rb_tree, 1012 buffer->io.mod_root, &buffer->io); 1013 buffer->io.mod_root = NULL; 1014 } 1015 lwkt_reltoken(&hmp->io_token); 1016 } 1017 1018 if (locked) { 1019 atomic_add_int(&hammer_count_refedbufs, 1); 1020 error = hammer_load_buffer(buffer, 0); 1021 /* NOTE: on error the buffer pointer is stale */ 1022 } else { 1023 error = 0; 1024 } 1025 return(error); 1026 } 1027 1028 /* 1029 * Release a reference on the buffer. On the 1->0 transition the 1030 * underlying IO will be released but the data reference is left 1031 * cached. 1032 * 1033 * Only destroy the structure itself if the related buffer cache buffer 1034 * was disassociated from it. This ties the management of the structure 1035 * to the buffer cache subsystem. buffer->ondisk determines whether the 1036 * embedded io is referenced or not. 1037 */ 1038 void 1039 hammer_rel_buffer(hammer_buffer_t buffer, int locked) 1040 { 1041 hammer_volume_t volume; 1042 hammer_mount_t hmp; 1043 struct buf *bp = NULL; 1044 int freeme = 0; 1045 1046 hmp = buffer->io.hmp; 1047 1048 if (hammer_rel_interlock(&buffer->io.lock, locked) == 0) 1049 return; 1050 1051 /* 1052 * hammer_count_refedbufs accounting. Decrement if we are in 1053 * the error path or if CHECK is clear. 1054 * 1055 * If we are not in the error path and CHECK is set the caller 1056 * probably just did a hammer_ref() and didn't account for it, 1057 * so we don't account for the loss here. 1058 */ 1059 if (locked || (buffer->io.lock.refs & HAMMER_REFS_CHECK) == 0) 1060 atomic_add_int(&hammer_count_refedbufs, -1); 1061 1062 /* 1063 * If the caller locked us or the normal released transitions 1064 * from 1->0 (and acquired the lock) attempt to release the 1065 * io. If the called locked us we tell hammer_io_release() 1066 * to flush (which would be the unload or failure path). 1067 */ 1068 bp = hammer_io_release(&buffer->io, locked); 1069 1070 /* 1071 * If the buffer has no bp association and no refs we can destroy 1072 * it. 1073 * 1074 * NOTE: It is impossible for any associated B-Tree nodes to have 1075 * refs if the buffer has no additional refs. 1076 */ 1077 if (buffer->io.bp == NULL && hammer_norefs(&buffer->io.lock)) { 1078 RB_REMOVE(hammer_buf_rb_tree, 1079 &buffer->io.hmp->rb_bufs_root, 1080 buffer); 1081 volume = buffer->io.volume; 1082 buffer->io.volume = NULL; /* sanity */ 1083 hammer_rel_volume(volume, 0); 1084 hammer_io_clear_modlist(&buffer->io); 1085 hammer_flush_buffer_nodes(buffer); 1086 KKASSERT(TAILQ_EMPTY(&buffer->node_list)); 1087 freeme = 1; 1088 } 1089 1090 /* 1091 * Cleanup 1092 */ 1093 hammer_rel_interlock_done(&buffer->io.lock, locked); 1094 if (bp) 1095 brelse(bp); 1096 if (freeme) { 1097 --hammer_count_buffers; 1098 kfree(buffer, hmp->m_misc); 1099 } 1100 } 1101 1102 /* 1103 * Access the filesystem buffer containing the specified hammer offset. 1104 * buf_offset is a conglomeration of the volume number and vol_buf_beg 1105 * relative buffer offset. It must also have bit 55 set to be valid. 1106 * (see hammer_off_t in hammer_disk.h). 1107 * 1108 * Any prior buffer in *bufferp will be released and replaced by the 1109 * requested buffer. 1110 * 1111 * NOTE: The buffer is indexed via its zoneX_offset but we allow the 1112 * passed cached *bufferp to match against either zoneX or zone2. 1113 */ 1114 static __inline 1115 void * 1116 _hammer_bread(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1117 int isnew, int *errorp, hammer_buffer_t *bufferp) 1118 { 1119 hammer_buffer_t buffer; 1120 int32_t xoff = (int32_t)buf_offset & HAMMER_BUFMASK; 1121 1122 buf_offset &= ~HAMMER_BUFMASK64; 1123 KKASSERT(HAMMER_ZONE(buf_offset) != 0); 1124 1125 buffer = *bufferp; 1126 if (buffer == NULL || (buffer->zone2_offset != buf_offset && 1127 buffer->zoneX_offset != buf_offset)) { 1128 if (buffer) 1129 hammer_rel_buffer(buffer, 0); 1130 buffer = hammer_get_buffer(hmp, buf_offset, bytes, isnew, errorp); 1131 *bufferp = buffer; 1132 } else { 1133 *errorp = 0; 1134 } 1135 1136 /* 1137 * Return a pointer to the buffer data. 1138 */ 1139 if (buffer == NULL) 1140 return(NULL); 1141 else 1142 return((char *)buffer->ondisk + xoff); 1143 } 1144 1145 void * 1146 hammer_bread(hammer_mount_t hmp, hammer_off_t buf_offset, 1147 int *errorp, hammer_buffer_t *bufferp) 1148 { 1149 return(_hammer_bread(hmp, buf_offset, HAMMER_BUFSIZE, 0, errorp, bufferp)); 1150 } 1151 1152 void * 1153 hammer_bread_ext(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1154 int *errorp, hammer_buffer_t *bufferp) 1155 { 1156 bytes = HAMMER_BUFSIZE_DOALIGN(bytes); 1157 return(_hammer_bread(hmp, buf_offset, bytes, 0, errorp, bufferp)); 1158 } 1159 1160 /* 1161 * Access the filesystem buffer containing the specified hammer offset. 1162 * No disk read operation occurs. The result buffer may contain garbage. 1163 * 1164 * Any prior buffer in *bufferp will be released and replaced by the 1165 * requested buffer. 1166 * 1167 * This function marks the buffer dirty but does not increment its 1168 * modify_refs count. 1169 */ 1170 void * 1171 hammer_bnew(hammer_mount_t hmp, hammer_off_t buf_offset, 1172 int *errorp, hammer_buffer_t *bufferp) 1173 { 1174 return(_hammer_bread(hmp, buf_offset, HAMMER_BUFSIZE, 1, errorp, bufferp)); 1175 } 1176 1177 void * 1178 hammer_bnew_ext(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1179 int *errorp, hammer_buffer_t *bufferp) 1180 { 1181 bytes = HAMMER_BUFSIZE_DOALIGN(bytes); 1182 return(_hammer_bread(hmp, buf_offset, bytes, 1, errorp, bufferp)); 1183 } 1184 1185 /************************************************************************ 1186 * NODES * 1187 ************************************************************************ 1188 * 1189 * Manage B-Tree nodes. B-Tree nodes represent the primary indexing 1190 * method used by the HAMMER filesystem. 1191 * 1192 * Unlike other HAMMER structures, a hammer_node can be PASSIVELY 1193 * associated with its buffer, and will only referenced the buffer while 1194 * the node itself is referenced. 1195 * 1196 * A hammer_node can also be passively associated with other HAMMER 1197 * structures, such as inodes, while retaining 0 references. These 1198 * associations can be cleared backwards using a pointer-to-pointer in 1199 * the hammer_node. 1200 * 1201 * This allows the HAMMER implementation to cache hammer_nodes long-term 1202 * and short-cut a great deal of the infrastructure's complexity. In 1203 * most cases a cached node can be reacquired without having to dip into 1204 * the B-Tree. 1205 */ 1206 hammer_node_t 1207 hammer_get_node(hammer_transaction_t trans, hammer_off_t node_offset, 1208 int isnew, int *errorp) 1209 { 1210 hammer_mount_t hmp = trans->hmp; 1211 hammer_node_t node; 1212 int doload; 1213 1214 KKASSERT(hammer_is_zone_btree(node_offset)); 1215 1216 /* 1217 * Locate the structure, allocating one if necessary. 1218 */ 1219 again: 1220 node = RB_LOOKUP(hammer_nod_rb_tree, &hmp->rb_nods_root, node_offset); 1221 if (node == NULL) { 1222 ++hammer_count_nodes; 1223 node = kmalloc(sizeof(*node), hmp->m_misc, M_WAITOK|M_ZERO|M_USE_RESERVE); 1224 node->node_offset = node_offset; 1225 node->hmp = hmp; 1226 TAILQ_INIT(&node->cursor_list); 1227 TAILQ_INIT(&node->cache_list); 1228 if (RB_INSERT(hammer_nod_rb_tree, &hmp->rb_nods_root, node)) { 1229 --hammer_count_nodes; 1230 kfree(node, hmp->m_misc); 1231 goto again; 1232 } 1233 doload = hammer_ref_interlock_true(&node->lock); 1234 } else { 1235 doload = hammer_ref_interlock(&node->lock); 1236 } 1237 if (doload) { 1238 *errorp = hammer_load_node(trans, node, isnew); 1239 if (*errorp) 1240 node = NULL; 1241 } else { 1242 KKASSERT(node->ondisk); 1243 *errorp = 0; 1244 hammer_io_advance(&node->buffer->io); 1245 } 1246 return(node); 1247 } 1248 1249 /* 1250 * Reference an already-referenced node. 0->1 transitions should assert 1251 * so we do not have to deal with hammer_ref() setting CHECK. 1252 */ 1253 void 1254 hammer_ref_node(hammer_node_t node) 1255 { 1256 KKASSERT(hammer_isactive(&node->lock) && node->ondisk != NULL); 1257 hammer_ref(&node->lock); 1258 } 1259 1260 /* 1261 * Load a node's on-disk data reference. Called with the node referenced 1262 * and interlocked. 1263 * 1264 * On return the node interlock will be unlocked. If a non-zero error code 1265 * is returned the node will also be dereferenced (and the caller's pointer 1266 * will be stale). 1267 */ 1268 static int 1269 hammer_load_node(hammer_transaction_t trans, hammer_node_t node, int isnew) 1270 { 1271 hammer_buffer_t buffer; 1272 hammer_off_t buf_offset; 1273 hammer_mount_t hmp = trans->hmp; 1274 int error; 1275 1276 error = 0; 1277 if (node->ondisk == NULL) { 1278 /* 1279 * This is a little confusing but the jist is that 1280 * node->buffer determines whether the node is on 1281 * the buffer's node_list and node->ondisk determines 1282 * whether the buffer is referenced. 1283 * 1284 * We could be racing a buffer release, in which case 1285 * node->buffer may become NULL while we are blocked 1286 * referencing the buffer. 1287 */ 1288 if ((buffer = node->buffer) != NULL) { 1289 error = hammer_ref_buffer(buffer); 1290 if (error == 0 && node->buffer == NULL) { 1291 TAILQ_INSERT_TAIL(&buffer->node_list, node, entry); 1292 node->buffer = buffer; 1293 } 1294 } else { 1295 buf_offset = node->node_offset & ~HAMMER_BUFMASK64; 1296 buffer = hammer_get_buffer(node->hmp, buf_offset, 1297 HAMMER_BUFSIZE, 0, &error); 1298 if (buffer) { 1299 KKASSERT(error == 0); 1300 TAILQ_INSERT_TAIL(&buffer->node_list, node, entry); 1301 node->buffer = buffer; 1302 } 1303 } 1304 if (error) 1305 goto failed; 1306 node->ondisk = (void *)((char *)buffer->ondisk + 1307 (node->node_offset & HAMMER_BUFMASK)); 1308 1309 /* 1310 * Check CRC. NOTE: Neither flag is set and the CRC is not 1311 * generated on new B-Tree nodes. 1312 */ 1313 if (isnew == 0 && 1314 (node->flags & HAMMER_NODE_CRCANY) == 0) { 1315 if (hammer_crc_test_btree(hmp->version, node->ondisk) == 0) { 1316 hdkprintf("CRC B-TREE NODE @ %016jx/%lu FAILED\n", 1317 (intmax_t)node->node_offset, 1318 sizeof(*node->ondisk)); 1319 if (hammer_debug_critical) 1320 Debugger("CRC FAILED: B-TREE NODE"); 1321 node->flags |= HAMMER_NODE_CRCBAD; 1322 } else { 1323 node->flags |= HAMMER_NODE_CRCGOOD; 1324 } 1325 } 1326 } 1327 if (node->flags & HAMMER_NODE_CRCBAD) { 1328 if (trans->flags & HAMMER_TRANSF_CRCDOM) 1329 error = EDOM; 1330 else 1331 error = EIO; 1332 } 1333 failed: 1334 if (error) { 1335 _hammer_rel_node(node, 1); 1336 } else { 1337 hammer_ref_interlock_done(&node->lock); 1338 } 1339 return (error); 1340 } 1341 1342 /* 1343 * Safely reference a node, interlock against flushes via the IO subsystem. 1344 */ 1345 hammer_node_t 1346 hammer_ref_node_safe(hammer_transaction_t trans, hammer_node_cache_t cache, 1347 int *errorp) 1348 { 1349 hammer_node_t node; 1350 int doload; 1351 1352 node = cache->node; 1353 if (node != NULL) { 1354 doload = hammer_ref_interlock(&node->lock); 1355 if (doload) { 1356 *errorp = hammer_load_node(trans, node, 0); 1357 if (*errorp) 1358 node = NULL; 1359 } else { 1360 KKASSERT(node->ondisk); 1361 if (node->flags & HAMMER_NODE_CRCBAD) { 1362 if (trans->flags & HAMMER_TRANSF_CRCDOM) 1363 *errorp = EDOM; 1364 else 1365 *errorp = EIO; 1366 _hammer_rel_node(node, 0); 1367 node = NULL; 1368 } else { 1369 *errorp = 0; 1370 } 1371 } 1372 } else { 1373 *errorp = ENOENT; 1374 } 1375 return(node); 1376 } 1377 1378 /* 1379 * Release a hammer_node. On the last release the node dereferences 1380 * its underlying buffer and may or may not be destroyed. 1381 * 1382 * If locked is non-zero the passed node has been interlocked by the 1383 * caller and we are in the failure/unload path, otherwise it has not and 1384 * we are doing a normal release. 1385 * 1386 * This function will dispose of the interlock and the reference. 1387 * On return the node pointer is stale. 1388 */ 1389 void 1390 _hammer_rel_node(hammer_node_t node, int locked) 1391 { 1392 hammer_buffer_t buffer; 1393 1394 /* 1395 * Deref the node. If this isn't the 1->0 transition we're basically 1396 * done. If locked is non-zero this function will just deref the 1397 * locked node and return 1, otherwise it will deref the locked 1398 * node and either lock and return 1 on the 1->0 transition or 1399 * not lock and return 0. 1400 */ 1401 if (hammer_rel_interlock(&node->lock, locked) == 0) 1402 return; 1403 1404 /* 1405 * Either locked was non-zero and we are interlocked, or the 1406 * hammer_rel_interlock() call returned non-zero and we are 1407 * interlocked. 1408 * 1409 * The ref-count must still be decremented if locked != 0 so 1410 * the cleanup required still varies a bit. 1411 * 1412 * hammer_flush_node() when called with 1 or 2 will dispose of 1413 * the lock and possible ref-count. 1414 */ 1415 if (node->ondisk == NULL) { 1416 hammer_flush_node(node, locked + 1); 1417 /* node is stale now */ 1418 return; 1419 } 1420 1421 /* 1422 * Do not disassociate the node from the buffer if it represents 1423 * a modified B-Tree node that still needs its crc to be generated. 1424 */ 1425 if (node->flags & HAMMER_NODE_NEEDSCRC) { 1426 hammer_rel_interlock_done(&node->lock, locked); 1427 return; 1428 } 1429 1430 /* 1431 * Do final cleanups and then either destroy the node and leave it 1432 * passively cached. The buffer reference is removed regardless. 1433 */ 1434 buffer = node->buffer; 1435 node->ondisk = NULL; 1436 1437 if ((node->flags & HAMMER_NODE_FLUSH) == 0) { 1438 /* 1439 * Normal release. 1440 */ 1441 hammer_rel_interlock_done(&node->lock, locked); 1442 } else { 1443 /* 1444 * Destroy the node. 1445 */ 1446 hammer_flush_node(node, locked + 1); 1447 /* node is stale */ 1448 1449 } 1450 hammer_rel_buffer(buffer, 0); 1451 } 1452 1453 void 1454 hammer_rel_node(hammer_node_t node) 1455 { 1456 _hammer_rel_node(node, 0); 1457 } 1458 1459 /* 1460 * Free space on-media associated with a B-Tree node. 1461 */ 1462 void 1463 hammer_delete_node(hammer_transaction_t trans, hammer_node_t node) 1464 { 1465 KKASSERT((node->flags & HAMMER_NODE_DELETED) == 0); 1466 node->flags |= HAMMER_NODE_DELETED; 1467 hammer_blockmap_free(trans, node->node_offset, sizeof(*node->ondisk)); 1468 } 1469 1470 /* 1471 * Passively cache a referenced hammer_node. The caller may release 1472 * the node on return. 1473 */ 1474 void 1475 hammer_cache_node(hammer_node_cache_t cache, hammer_node_t node) 1476 { 1477 /* 1478 * If the node doesn't exist, or is being deleted, don't cache it! 1479 * 1480 * The node can only ever be NULL in the I/O failure path. 1481 */ 1482 if (node == NULL || (node->flags & HAMMER_NODE_DELETED)) 1483 return; 1484 if (cache->node == node) 1485 return; 1486 while (cache->node) 1487 hammer_uncache_node(cache); 1488 if (node->flags & HAMMER_NODE_DELETED) 1489 return; 1490 cache->node = node; 1491 TAILQ_INSERT_TAIL(&node->cache_list, cache, entry); 1492 } 1493 1494 void 1495 hammer_uncache_node(hammer_node_cache_t cache) 1496 { 1497 hammer_node_t node; 1498 1499 if ((node = cache->node) != NULL) { 1500 TAILQ_REMOVE(&node->cache_list, cache, entry); 1501 cache->node = NULL; 1502 if (TAILQ_EMPTY(&node->cache_list)) 1503 hammer_flush_node(node, 0); 1504 } 1505 } 1506 1507 /* 1508 * Remove a node's cache references and destroy the node if it has no 1509 * other references or backing store. 1510 * 1511 * locked == 0 Normal unlocked operation 1512 * locked == 1 Call hammer_rel_interlock_done(..., 0); 1513 * locked == 2 Call hammer_rel_interlock_done(..., 1); 1514 * 1515 * XXX for now this isn't even close to being MPSAFE so the refs check 1516 * is sufficient. 1517 */ 1518 void 1519 hammer_flush_node(hammer_node_t node, int locked) 1520 { 1521 hammer_node_cache_t cache; 1522 hammer_buffer_t buffer; 1523 hammer_mount_t hmp = node->hmp; 1524 int dofree; 1525 1526 while ((cache = TAILQ_FIRST(&node->cache_list)) != NULL) { 1527 TAILQ_REMOVE(&node->cache_list, cache, entry); 1528 cache->node = NULL; 1529 } 1530 1531 /* 1532 * NOTE: refs is predisposed if another thread is blocking and 1533 * will be larger than 0 in that case. We aren't MPSAFE 1534 * here. 1535 */ 1536 if (node->ondisk == NULL && hammer_norefs(&node->lock)) { 1537 KKASSERT((node->flags & HAMMER_NODE_NEEDSCRC) == 0); 1538 RB_REMOVE(hammer_nod_rb_tree, &node->hmp->rb_nods_root, node); 1539 if ((buffer = node->buffer) != NULL) { 1540 node->buffer = NULL; 1541 TAILQ_REMOVE(&buffer->node_list, node, entry); 1542 /* buffer is unreferenced because ondisk is NULL */ 1543 } 1544 dofree = 1; 1545 } else { 1546 dofree = 0; 1547 } 1548 1549 /* 1550 * Deal with the interlock if locked == 1 or locked == 2. 1551 */ 1552 if (locked) 1553 hammer_rel_interlock_done(&node->lock, locked - 1); 1554 1555 /* 1556 * Destroy if requested 1557 */ 1558 if (dofree) { 1559 --hammer_count_nodes; 1560 kfree(node, hmp->m_misc); 1561 } 1562 } 1563 1564 /* 1565 * Flush passively cached B-Tree nodes associated with this buffer. 1566 * This is only called when the buffer is about to be destroyed, so 1567 * none of the nodes should have any references. The buffer is locked. 1568 * 1569 * We may be interlocked with the buffer. 1570 */ 1571 void 1572 hammer_flush_buffer_nodes(hammer_buffer_t buffer) 1573 { 1574 hammer_node_t node; 1575 1576 while ((node = TAILQ_FIRST(&buffer->node_list)) != NULL) { 1577 KKASSERT(node->ondisk == NULL); 1578 KKASSERT((node->flags & HAMMER_NODE_NEEDSCRC) == 0); 1579 1580 if (hammer_try_interlock_norefs(&node->lock)) { 1581 hammer_ref(&node->lock); 1582 node->flags |= HAMMER_NODE_FLUSH; 1583 _hammer_rel_node(node, 1); 1584 } else { 1585 KKASSERT(node->buffer != NULL); 1586 buffer = node->buffer; 1587 node->buffer = NULL; 1588 TAILQ_REMOVE(&buffer->node_list, node, entry); 1589 /* buffer is unreferenced because ondisk is NULL */ 1590 } 1591 } 1592 } 1593 1594 1595 /************************************************************************ 1596 * ALLOCATORS * 1597 ************************************************************************/ 1598 1599 /* 1600 * Allocate a B-Tree node. 1601 */ 1602 hammer_node_t 1603 hammer_alloc_btree(hammer_transaction_t trans, hammer_off_t hint, int *errorp) 1604 { 1605 hammer_buffer_t buffer = NULL; 1606 hammer_node_t node = NULL; 1607 hammer_off_t node_offset; 1608 1609 node_offset = hammer_blockmap_alloc(trans, HAMMER_ZONE_BTREE_INDEX, 1610 sizeof(struct hammer_node_ondisk), 1611 hint, errorp); 1612 if (*errorp == 0) { 1613 node = hammer_get_node(trans, node_offset, 1, errorp); 1614 hammer_modify_node_noundo(trans, node); 1615 bzero(node->ondisk, sizeof(*node->ondisk)); 1616 hammer_modify_node_done(node); 1617 } 1618 if (buffer) 1619 hammer_rel_buffer(buffer, 0); 1620 return(node); 1621 } 1622 1623 /* 1624 * Allocate data. If the address of a data buffer is supplied then 1625 * any prior non-NULL *data_bufferp will be released and *data_bufferp 1626 * will be set to the related buffer. The caller must release it when 1627 * finally done. The initial *data_bufferp should be set to NULL by 1628 * the caller. 1629 * 1630 * The caller is responsible for making hammer_modify*() calls on the 1631 * *data_bufferp. 1632 */ 1633 void * 1634 hammer_alloc_data(hammer_transaction_t trans, int32_t data_len, 1635 uint16_t rec_type, hammer_off_t *data_offsetp, 1636 hammer_buffer_t *data_bufferp, 1637 hammer_off_t hint, int *errorp) 1638 { 1639 void *data; 1640 int zone; 1641 1642 /* 1643 * Allocate data directly from blockmap. 1644 */ 1645 if (data_len) { 1646 switch(rec_type) { 1647 case HAMMER_RECTYPE_INODE: 1648 case HAMMER_RECTYPE_DIRENTRY: 1649 case HAMMER_RECTYPE_EXT: 1650 case HAMMER_RECTYPE_FIX: 1651 case HAMMER_RECTYPE_PFS: 1652 case HAMMER_RECTYPE_SNAPSHOT: 1653 case HAMMER_RECTYPE_CONFIG: 1654 zone = HAMMER_ZONE_META_INDEX; 1655 break; 1656 case HAMMER_RECTYPE_DATA: 1657 case HAMMER_RECTYPE_DB: 1658 /* 1659 * Only mirror-write comes here. 1660 * Regular allocation path uses blockmap reservation. 1661 */ 1662 zone = hammer_data_zone_index(data_len); 1663 if (zone == HAMMER_ZONE_LARGE_DATA_INDEX) { 1664 /* round up */ 1665 data_len = HAMMER_BUFSIZE_DOALIGN(data_len); 1666 } 1667 break; 1668 default: 1669 hpanic("rec_type %04x unknown", rec_type); 1670 zone = HAMMER_ZONE_UNAVAIL_INDEX; /* NOT REACHED */ 1671 break; 1672 } 1673 *data_offsetp = hammer_blockmap_alloc(trans, zone, data_len, 1674 hint, errorp); 1675 } else { 1676 *data_offsetp = 0; 1677 } 1678 1679 data = NULL; 1680 if (*errorp == 0 && data_bufferp && data_len) 1681 data = hammer_bread_ext(trans->hmp, *data_offsetp, data_len, 1682 errorp, data_bufferp); 1683 return(data); 1684 } 1685 1686 /* 1687 * Sync dirty buffers to the media and clean-up any loose ends. 1688 * 1689 * These functions do not start the flusher going, they simply 1690 * queue everything up to the flusher. 1691 */ 1692 static int hammer_sync_scan2(struct mount *mp, struct vnode *vp, void *data); 1693 1694 struct hammer_sync_info { 1695 int error; 1696 }; 1697 1698 int 1699 hammer_queue_inodes_flusher(hammer_mount_t hmp, int waitfor) 1700 { 1701 struct hammer_sync_info info; 1702 1703 info.error = 0; 1704 if (waitfor == MNT_WAIT) { 1705 vsyncscan(hmp->mp, VMSC_GETVP | VMSC_ONEPASS, 1706 hammer_sync_scan2, &info); 1707 } else { 1708 vsyncscan(hmp->mp, VMSC_GETVP | VMSC_ONEPASS | VMSC_NOWAIT, 1709 hammer_sync_scan2, &info); 1710 } 1711 return(info.error); 1712 } 1713 1714 /* 1715 * Filesystem sync. If doing a synchronous sync make a second pass on 1716 * the vnodes in case any were already flushing during the first pass, 1717 * and activate the flusher twice (the second time brings the UNDO FIFO's 1718 * start position up to the end position after the first call). 1719 * 1720 * If doing a lazy sync make just one pass on the vnode list, ignoring 1721 * any new vnodes added to the list while the sync is in progress. 1722 */ 1723 int 1724 hammer_sync_hmp(hammer_mount_t hmp, int waitfor) 1725 { 1726 struct hammer_sync_info info; 1727 int flags; 1728 1729 flags = VMSC_GETVP; 1730 if (waitfor & MNT_LAZY) 1731 flags |= VMSC_ONEPASS; 1732 1733 info.error = 0; 1734 vsyncscan(hmp->mp, flags | VMSC_NOWAIT, hammer_sync_scan2, &info); 1735 1736 if (info.error == 0 && (waitfor & MNT_WAIT)) { 1737 vsyncscan(hmp->mp, flags, hammer_sync_scan2, &info); 1738 } 1739 if (waitfor == MNT_WAIT) { 1740 hammer_flusher_sync(hmp); 1741 hammer_flusher_sync(hmp); 1742 } else { 1743 hammer_flusher_async(hmp, NULL); 1744 hammer_flusher_async(hmp, NULL); 1745 } 1746 return(info.error); 1747 } 1748 1749 static int 1750 hammer_sync_scan2(struct mount *mp, struct vnode *vp, void *data) 1751 { 1752 struct hammer_sync_info *info = data; 1753 hammer_inode_t ip; 1754 int error; 1755 1756 ip = VTOI(vp); 1757 if (ip == NULL) 1758 return(0); 1759 if (vp->v_type == VNON || vp->v_type == VBAD) { 1760 vclrisdirty(vp); 1761 return(0); 1762 } 1763 if ((ip->flags & HAMMER_INODE_MODMASK) == 0 && 1764 RB_EMPTY(&vp->v_rbdirty_tree)) { 1765 vclrisdirty(vp); 1766 return(0); 1767 } 1768 error = VOP_FSYNC(vp, MNT_NOWAIT, 0); 1769 if (error) 1770 info->error = error; 1771 return(0); 1772 } 1773