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 struct hammer_volume_ondisk *ondisk; 115 struct hammer_volume_ondisk *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_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; 184 185 /* 186 * Initialize the volume header with data if the data is specified. 187 */ 188 if (ronly == 0 && data) { 189 img = (struct hammer_volume_ondisk *)data; 190 if (ondisk->vol_signature == HAMMER_FSBUF_VOLUME) { 191 hkprintf("Formatting of valid HAMMER volume " 192 "%s denied. Erase with 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", 201 volume->vol_name); 202 for (i = 0; i < (int)sizeof(ondisk->vol_signature); i++) { 203 kprintf("%02x", ((char*)&ondisk->vol_signature)[i] & 0xFF); 204 if (i != (int)sizeof(ondisk->vol_signature) - 1) 205 kprintf(" "); 206 } 207 kprintf("\n"); 208 error = EFTYPE; 209 goto late_failure; 210 } 211 volume->vol_no = ondisk->vol_no; 212 volume->vol_flags = ondisk->vol_flags; 213 volume->maxbuf_off = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 214 ondisk->vol_buf_end - ondisk->vol_buf_beg); 215 216 if (RB_EMPTY(&hmp->rb_vols_root)) { 217 hmp->fsid = ondisk->vol_fsid; 218 } else if (bcmp(&hmp->fsid, &ondisk->vol_fsid, sizeof(uuid_t))) { 219 hkprintf("volume %s's fsid does not match other volumes\n", 220 volume->vol_name); 221 error = EFTYPE; 222 goto late_failure; 223 } 224 225 /* 226 * Insert the volume structure into the red-black tree. 227 */ 228 if (RB_INSERT(hammer_vol_rb_tree, &hmp->rb_vols_root, volume)) { 229 hkprintf("volume %s has a duplicate vol_no %d\n", 230 volume->vol_name, volume->vol_no); 231 error = EEXIST; 232 } 233 234 if (error == 0) 235 HAMMER_VOLUME_NUMBER_ADD(hmp, volume); 236 237 /* 238 * Set the root volume . HAMMER special cases rootvol the structure. 239 * We do not hold a ref because this would prevent related I/O 240 * from being flushed. 241 */ 242 if (error == 0 && ondisk->vol_rootvol == ondisk->vol_no) { 243 hmp->rootvol = volume; 244 hmp->nvolumes = ondisk->vol_count; 245 if (bp) { 246 brelse(bp); 247 bp = NULL; 248 } 249 hmp->mp->mnt_stat.f_blocks += ondisk->vol0_stat_bigblocks * 250 HAMMER_BUFFERS_PER_BIGBLOCK; 251 hmp->mp->mnt_vstat.f_blocks += ondisk->vol0_stat_bigblocks * 252 HAMMER_BUFFERS_PER_BIGBLOCK; 253 } 254 late_failure: 255 if (bp) 256 brelse(bp); 257 if (error) { 258 /*vinvalbuf(volume->devvp, V_SAVE, 0, 0);*/ 259 if (setmp) 260 volume->devvp->v_rdev->si_mountpoint = NULL; 261 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 262 VOP_CLOSE(volume->devvp, ronly ? FREAD : FREAD|FWRITE, NULL); 263 vn_unlock(volume->devvp); 264 hammer_free_volume(volume); 265 } 266 return (error); 267 } 268 269 /* 270 * This is called for each volume when updating the mount point from 271 * read-write to read-only or vise-versa. 272 */ 273 int 274 hammer_adjust_volume_mode(hammer_volume_t volume, void *data __unused) 275 { 276 if (volume->devvp) { 277 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 278 if (volume->io.hmp->ronly) { 279 /* do not call vinvalbuf */ 280 VOP_OPEN(volume->devvp, FREAD, FSCRED, NULL); 281 VOP_CLOSE(volume->devvp, FREAD|FWRITE, NULL); 282 } else { 283 /* do not call vinvalbuf */ 284 VOP_OPEN(volume->devvp, FREAD|FWRITE, FSCRED, NULL); 285 VOP_CLOSE(volume->devvp, FREAD, NULL); 286 } 287 vn_unlock(volume->devvp); 288 } 289 return(0); 290 } 291 292 /* 293 * Unload and free a HAMMER volume. Must return >= 0 to continue scan 294 * so returns -1 on failure. 295 */ 296 int 297 hammer_unload_volume(hammer_volume_t volume, void *data) 298 { 299 hammer_mount_t hmp = volume->io.hmp; 300 struct buf *bp = NULL; 301 struct hammer_volume_ondisk *img; 302 int ronly = ((hmp->mp->mnt_flag & MNT_RDONLY) ? 1 : 0); 303 int error; 304 305 /* 306 * Clear the volume header with data if the data is specified. 307 */ 308 if (ronly == 0 && data && volume->devvp) { 309 img = (struct hammer_volume_ondisk *)data; 310 error = bread(volume->devvp, 0LL, HAMMER_BUFSIZE, &bp); 311 if (error || bp->b_bcount < sizeof(*img)) { 312 hmkprintf(hmp, "Failed to read volume header: %d\n", error); 313 brelse(bp); 314 } else { 315 bcopy(img, bp->b_data, sizeof(*img)); 316 error = bwrite(bp); 317 if (error) 318 hmkprintf(hmp, "Failed to clear volume header: %d\n", 319 error); 320 } 321 } 322 323 /* 324 * Clean up the root volume pointer, which is held unlocked in hmp. 325 */ 326 if (hmp->rootvol == volume) 327 hmp->rootvol = NULL; 328 329 /* 330 * We must not flush a dirty buffer to disk on umount. It should 331 * have already been dealt with by the flusher, or we may be in 332 * catastrophic failure. 333 */ 334 hammer_io_clear_modify(&volume->io, 1); 335 volume->io.waitdep = 1; 336 337 /* 338 * Clean up the persistent ref ioerror might have on the volume 339 */ 340 if (volume->io.ioerror) 341 hammer_io_clear_error_noassert(&volume->io); 342 343 /* 344 * This should release the bp. Releasing the volume with flush set 345 * implies the interlock is set. 346 */ 347 hammer_ref_interlock_true(&volume->io.lock); 348 hammer_rel_volume(volume, 1); 349 KKASSERT(volume->io.bp == NULL); 350 351 /* 352 * There should be no references on the volume. 353 */ 354 KKASSERT(hammer_norefs(&volume->io.lock)); 355 356 volume->ondisk = NULL; 357 if (volume->devvp) { 358 if (volume->devvp->v_rdev && 359 volume->devvp->v_rdev->si_mountpoint == hmp->mp) { 360 volume->devvp->v_rdev->si_mountpoint = NULL; 361 } 362 if (ronly) { 363 /* 364 * Make sure we don't sync anything to disk if we 365 * are in read-only mode (1) or critically-errored 366 * (2). Note that there may be dirty buffers in 367 * normal read-only mode from crash recovery. 368 */ 369 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 370 vinvalbuf(volume->devvp, 0, 0, 0); 371 VOP_CLOSE(volume->devvp, FREAD, NULL); 372 vn_unlock(volume->devvp); 373 } else { 374 /* 375 * Normal termination, save any dirty buffers 376 * (XXX there really shouldn't be any). 377 */ 378 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 379 vinvalbuf(volume->devvp, V_SAVE, 0, 0); 380 VOP_CLOSE(volume->devvp, FREAD|FWRITE, NULL); 381 vn_unlock(volume->devvp); 382 } 383 } 384 385 /* 386 * Destroy the structure 387 */ 388 RB_REMOVE(hammer_vol_rb_tree, &hmp->rb_vols_root, volume); 389 HAMMER_VOLUME_NUMBER_DEL(hmp, volume); 390 hammer_free_volume(volume); 391 return(0); 392 } 393 394 static 395 void 396 hammer_free_volume(hammer_volume_t volume) 397 { 398 hammer_mount_t hmp = volume->io.hmp; 399 400 if (volume->vol_name) { 401 kfree(volume->vol_name, hmp->m_misc); 402 volume->vol_name = NULL; 403 } 404 if (volume->devvp) { 405 vrele(volume->devvp); 406 volume->devvp = NULL; 407 } 408 --hammer_count_volumes; 409 kfree(volume, hmp->m_misc); 410 } 411 412 /* 413 * Get a HAMMER volume. The volume must already exist. 414 */ 415 hammer_volume_t 416 hammer_get_volume(hammer_mount_t hmp, int32_t vol_no, int *errorp) 417 { 418 struct hammer_volume *volume; 419 420 /* 421 * Locate the volume structure 422 */ 423 volume = RB_LOOKUP(hammer_vol_rb_tree, &hmp->rb_vols_root, vol_no); 424 if (volume == NULL) { 425 *errorp = ENOENT; 426 return(NULL); 427 } 428 429 /* 430 * Reference the volume, load/check the data on the 0->1 transition. 431 * hammer_load_volume() will dispose of the interlock on return, 432 * and also clean up the ref count on error. 433 */ 434 if (hammer_ref_interlock(&volume->io.lock)) { 435 *errorp = hammer_load_volume(volume); 436 if (*errorp) 437 volume = NULL; 438 } else { 439 KKASSERT(volume->ondisk); 440 *errorp = 0; 441 } 442 return(volume); 443 } 444 445 int 446 hammer_ref_volume(hammer_volume_t volume) 447 { 448 int error; 449 450 /* 451 * Reference the volume and deal with the check condition used to 452 * load its ondisk info. 453 */ 454 if (hammer_ref_interlock(&volume->io.lock)) { 455 error = hammer_load_volume(volume); 456 } else { 457 KKASSERT(volume->ondisk); 458 error = 0; 459 } 460 return (error); 461 } 462 463 /* 464 * May be called without fs_token 465 */ 466 hammer_volume_t 467 hammer_get_root_volume(hammer_mount_t hmp, int *errorp) 468 { 469 hammer_volume_t volume; 470 471 volume = hmp->rootvol; 472 KKASSERT(volume != NULL); 473 474 /* 475 * Reference the volume and deal with the check condition used to 476 * load its ondisk info. 477 */ 478 if (hammer_ref_interlock(&volume->io.lock)) { 479 lwkt_gettoken(&volume->io.hmp->fs_token); 480 *errorp = hammer_load_volume(volume); 481 lwkt_reltoken(&volume->io.hmp->fs_token); 482 if (*errorp) 483 volume = NULL; 484 } else { 485 KKASSERT(volume->ondisk); 486 *errorp = 0; 487 } 488 return (volume); 489 } 490 491 /* 492 * Load a volume's on-disk information. The volume must be referenced and 493 * the interlock is held on call. The interlock will be released on return. 494 * The reference will also be released on return if an error occurs. 495 */ 496 static int 497 hammer_load_volume(hammer_volume_t volume) 498 { 499 int error; 500 501 if (volume->ondisk == NULL) { 502 error = hammer_io_read(volume->devvp, &volume->io, 503 HAMMER_BUFSIZE); 504 if (error == 0) { 505 volume->ondisk = (void *)volume->io.bp->b_data; 506 hammer_ref_interlock_done(&volume->io.lock); 507 } else { 508 hammer_rel_volume(volume, 1); 509 } 510 } else { 511 error = 0; 512 } 513 return(error); 514 } 515 516 /* 517 * Release a previously acquired reference on the volume. 518 * 519 * Volumes are not unloaded from memory during normal operation. 520 * 521 * May be called without fs_token 522 */ 523 void 524 hammer_rel_volume(hammer_volume_t volume, int locked) 525 { 526 struct buf *bp; 527 528 if (hammer_rel_interlock(&volume->io.lock, locked)) { 529 lwkt_gettoken(&volume->io.hmp->fs_token); 530 volume->ondisk = NULL; 531 bp = hammer_io_release(&volume->io, locked); 532 lwkt_reltoken(&volume->io.hmp->fs_token); 533 hammer_rel_interlock_done(&volume->io.lock, locked); 534 if (bp) 535 brelse(bp); 536 } 537 } 538 539 int 540 hammer_mountcheck_volumes(hammer_mount_t hmp) 541 { 542 hammer_volume_t vol; 543 int i; 544 545 HAMMER_VOLUME_NUMBER_FOREACH(hmp, i) { 546 vol = RB_LOOKUP(hammer_vol_rb_tree, &hmp->rb_vols_root, i); 547 if (vol == NULL) 548 return(EINVAL); 549 } 550 return(0); 551 } 552 553 int 554 hammer_get_installed_volumes(hammer_mount_t hmp) 555 { 556 int i, ret = 0; 557 558 HAMMER_VOLUME_NUMBER_FOREACH(hmp, i) 559 ret++; 560 return(ret); 561 } 562 563 /************************************************************************ 564 * BUFFERS * 565 ************************************************************************ 566 * 567 * Manage buffers. Currently most blockmap-backed zones are direct-mapped 568 * to zone-2 buffer offsets, without a translation stage. However, the 569 * hammer_buffer structure is indexed by its zoneX_offset, not its 570 * zone2_offset. 571 * 572 * The proper zone must be maintained throughout the code-base all the way 573 * through to the big-block allocator, or routines like hammer_del_buffers() 574 * will not be able to locate all potentially conflicting buffers. 575 */ 576 577 /* 578 * Helper function returns whether a zone offset can be directly translated 579 * to a raw buffer index or not. Really only the volume and undo zones 580 * can't be directly translated. Volumes are special-cased and undo zones 581 * shouldn't be aliased accessed in read-only mode. 582 * 583 * This function is ONLY used to detect aliased zones during a read-only 584 * mount. 585 */ 586 static __inline int 587 hammer_direct_zone(hammer_off_t buf_offset) 588 { 589 int zone = HAMMER_ZONE_DECODE(buf_offset); 590 591 return(hammer_is_direct_mapped_index(zone)); 592 } 593 594 hammer_buffer_t 595 hammer_get_buffer(hammer_mount_t hmp, hammer_off_t buf_offset, 596 int bytes, int isnew, int *errorp) 597 { 598 hammer_buffer_t buffer; 599 hammer_volume_t volume; 600 hammer_off_t zone2_offset; 601 hammer_io_type_t iotype; 602 int vol_no; 603 int zone; 604 605 buf_offset &= ~HAMMER_BUFMASK64; 606 again: 607 /* 608 * Shortcut if the buffer is already cached 609 */ 610 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, buf_offset); 611 if (buffer) { 612 /* 613 * Once refed the ondisk field will not be cleared by 614 * any other action. Shortcut the operation if the 615 * ondisk structure is valid. 616 */ 617 found_aliased: 618 if (hammer_ref_interlock(&buffer->io.lock) == 0) { 619 hammer_io_advance(&buffer->io); 620 KKASSERT(buffer->ondisk); 621 *errorp = 0; 622 return(buffer); 623 } 624 625 /* 626 * 0->1 transition or defered 0->1 transition (CHECK), 627 * interlock now held. Shortcut if ondisk is already 628 * assigned. 629 */ 630 atomic_add_int(&hammer_count_refedbufs, 1); 631 if (buffer->ondisk) { 632 hammer_io_advance(&buffer->io); 633 hammer_ref_interlock_done(&buffer->io.lock); 634 *errorp = 0; 635 return(buffer); 636 } 637 638 /* 639 * The buffer is no longer loose if it has a ref, and 640 * cannot become loose once it gains a ref. Loose 641 * buffers will never be in a modified state. This should 642 * only occur on the 0->1 transition of refs. 643 * 644 * lose_root can be modified via a biodone() interrupt 645 * so the io_token must be held. 646 */ 647 if (buffer->io.mod_root == &hmp->lose_root) { 648 lwkt_gettoken(&hmp->io_token); 649 if (buffer->io.mod_root == &hmp->lose_root) { 650 RB_REMOVE(hammer_mod_rb_tree, 651 buffer->io.mod_root, &buffer->io); 652 buffer->io.mod_root = NULL; 653 KKASSERT(buffer->io.modified == 0); 654 } 655 lwkt_reltoken(&hmp->io_token); 656 } 657 goto found; 658 } else if (hmp->ronly && hammer_direct_zone(buf_offset)) { 659 /* 660 * If this is a read-only mount there could be an alias 661 * in the raw-zone. If there is we use that buffer instead. 662 * 663 * rw mounts will not have aliases. Also note when going 664 * from ro -> rw the recovered raw buffers are flushed and 665 * reclaimed, so again there will not be any aliases once 666 * the mount is rw. 667 */ 668 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 669 hammer_xlate_to_zone2(buf_offset)); 670 if (buffer) { 671 if (hammer_debug_general & 0x0001) { 672 hkrateprintf(&hmp->kdiag, 673 "recovered aliased %016jx\n", 674 (intmax_t)buf_offset); 675 } 676 goto found_aliased; 677 } 678 } 679 680 /* 681 * What is the buffer class? 682 */ 683 zone = HAMMER_ZONE_DECODE(buf_offset); 684 685 switch(zone) { 686 case HAMMER_ZONE_LARGE_DATA_INDEX: 687 case HAMMER_ZONE_SMALL_DATA_INDEX: 688 iotype = HAMMER_STRUCTURE_DATA_BUFFER; 689 break; 690 case HAMMER_ZONE_UNDO_INDEX: 691 iotype = HAMMER_STRUCTURE_UNDO_BUFFER; 692 break; 693 case HAMMER_ZONE_META_INDEX: 694 default: 695 /* 696 * NOTE: inode data and directory entries are placed in this 697 * zone. inode atime/mtime is updated in-place and thus 698 * buffers containing inodes must be synchronized as 699 * meta-buffers, same as buffers containing B-Tree info. 700 */ 701 iotype = HAMMER_STRUCTURE_META_BUFFER; 702 break; 703 } 704 705 /* 706 * Handle blockmap offset translations 707 */ 708 if (hammer_is_zone2_mapped_index(zone)) { 709 zone2_offset = hammer_blockmap_lookup(hmp, buf_offset, errorp); 710 } else if (zone == HAMMER_ZONE_UNDO_INDEX) { 711 zone2_offset = hammer_undo_lookup(hmp, buf_offset, errorp); 712 } else { 713 /* Must be zone-2 (not 1 or 4 or 15) */ 714 KKASSERT(zone == HAMMER_ZONE_RAW_BUFFER_INDEX); 715 zone2_offset = buf_offset; 716 *errorp = 0; 717 } 718 if (*errorp) 719 return(NULL); 720 721 /* 722 * NOTE: zone2_offset and maxbuf_off are both full zone-2 offset 723 * specifications. 724 */ 725 KKASSERT((zone2_offset & HAMMER_OFF_ZONE_MASK) == 726 HAMMER_ZONE_RAW_BUFFER); 727 vol_no = HAMMER_VOL_DECODE(zone2_offset); 728 volume = hammer_get_volume(hmp, vol_no, errorp); 729 if (volume == NULL) 730 return(NULL); 731 732 KKASSERT(zone2_offset < volume->maxbuf_off); 733 734 /* 735 * Allocate a new buffer structure. We will check for races later. 736 */ 737 ++hammer_count_buffers; 738 buffer = kmalloc(sizeof(*buffer), hmp->m_misc, 739 M_WAITOK|M_ZERO|M_USE_RESERVE); 740 buffer->zone2_offset = zone2_offset; 741 buffer->zoneX_offset = buf_offset; 742 743 hammer_io_init(&buffer->io, volume, iotype); 744 buffer->io.offset = hammer_xlate_to_phys(volume->ondisk, zone2_offset); 745 buffer->io.bytes = bytes; 746 TAILQ_INIT(&buffer->clist); 747 hammer_ref_interlock_true(&buffer->io.lock); 748 749 /* 750 * Insert the buffer into the RB tree and handle late collisions. 751 */ 752 if (RB_INSERT(hammer_buf_rb_tree, &hmp->rb_bufs_root, buffer)) { 753 hammer_rel_volume(volume, 0); 754 buffer->io.volume = NULL; /* safety */ 755 if (hammer_rel_interlock(&buffer->io.lock, 1)) /* safety */ 756 hammer_rel_interlock_done(&buffer->io.lock, 1); 757 --hammer_count_buffers; 758 kfree(buffer, hmp->m_misc); 759 goto again; 760 } 761 atomic_add_int(&hammer_count_refedbufs, 1); 762 found: 763 764 /* 765 * The buffer is referenced and interlocked. Load the buffer 766 * if necessary. hammer_load_buffer() deals with the interlock 767 * and, if an error is returned, also deals with the ref. 768 */ 769 if (buffer->ondisk == NULL) { 770 *errorp = hammer_load_buffer(buffer, isnew); 771 if (*errorp) 772 buffer = NULL; 773 } else { 774 hammer_io_advance(&buffer->io); 775 hammer_ref_interlock_done(&buffer->io.lock); 776 *errorp = 0; 777 } 778 return(buffer); 779 } 780 781 /* 782 * This is used by the direct-read code to deal with large-data buffers 783 * created by the reblocker and mirror-write code. The direct-read code 784 * bypasses the HAMMER buffer subsystem and so any aliased dirty or write- 785 * running hammer buffers must be fully synced to disk before we can issue 786 * the direct-read. 787 * 788 * This code path is not considered critical as only the rebocker and 789 * mirror-write code will create large-data buffers via the HAMMER buffer 790 * subsystem. They do that because they operate at the B-Tree level and 791 * do not access the vnode/inode structures. 792 */ 793 void 794 hammer_sync_buffers(hammer_mount_t hmp, hammer_off_t base_offset, int bytes) 795 { 796 hammer_buffer_t buffer; 797 int error; 798 799 KKASSERT((base_offset & HAMMER_OFF_ZONE_MASK) == 800 HAMMER_ZONE_LARGE_DATA); 801 802 while (bytes > 0) { 803 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 804 base_offset); 805 if (buffer && (buffer->io.modified || buffer->io.running)) { 806 error = hammer_ref_buffer(buffer); 807 if (error == 0) { 808 hammer_io_wait(&buffer->io); 809 if (buffer->io.modified) { 810 hammer_io_write_interlock(&buffer->io); 811 hammer_io_flush(&buffer->io, 0); 812 hammer_io_done_interlock(&buffer->io); 813 hammer_io_wait(&buffer->io); 814 } 815 hammer_rel_buffer(buffer, 0); 816 } 817 } 818 base_offset += HAMMER_BUFSIZE; 819 bytes -= HAMMER_BUFSIZE; 820 } 821 } 822 823 /* 824 * Destroy all buffers covering the specified zoneX offset range. This 825 * is called when the related blockmap layer2 entry is freed or when 826 * a direct write bypasses our buffer/buffer-cache subsystem. 827 * 828 * The buffers may be referenced by the caller itself. Setting reclaim 829 * will cause the buffer to be destroyed when it's ref count reaches zero. 830 * 831 * Return 0 on success, EAGAIN if some buffers could not be destroyed due 832 * to additional references held by other threads, or some other (typically 833 * fatal) error. 834 */ 835 int 836 hammer_del_buffers(hammer_mount_t hmp, hammer_off_t base_offset, 837 hammer_off_t zone2_offset, int bytes, 838 int report_conflicts) 839 { 840 hammer_buffer_t buffer; 841 hammer_volume_t volume; 842 int vol_no; 843 int error; 844 int ret_error; 845 846 vol_no = HAMMER_VOL_DECODE(zone2_offset); 847 volume = hammer_get_volume(hmp, vol_no, &ret_error); 848 KKASSERT(ret_error == 0); 849 850 while (bytes > 0) { 851 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 852 base_offset); 853 if (buffer) { 854 error = hammer_ref_buffer(buffer); 855 if (hammer_debug_general & 0x20000) { 856 hkprintf("delbufr %016jx rerr=%d 1ref=%d\n", 857 (intmax_t)buffer->zoneX_offset, 858 error, 859 hammer_oneref(&buffer->io.lock)); 860 } 861 if (error == 0 && !hammer_oneref(&buffer->io.lock)) { 862 error = EAGAIN; 863 hammer_rel_buffer(buffer, 0); 864 } 865 if (error == 0) { 866 KKASSERT(buffer->zone2_offset == zone2_offset); 867 hammer_io_clear_modify(&buffer->io, 1); 868 buffer->io.reclaim = 1; 869 buffer->io.waitdep = 1; 870 KKASSERT(buffer->io.volume == volume); 871 hammer_rel_buffer(buffer, 0); 872 } 873 } else { 874 error = hammer_io_inval(volume, zone2_offset); 875 } 876 if (error) { 877 ret_error = error; 878 if (report_conflicts || 879 (hammer_debug_general & 0x8000)) { 880 krateprintf(&hmp->kdiag, 881 "hammer_del_buffers: unable to " 882 "invalidate %016llx buffer=%p " 883 "rep=%d lkrefs=%08x\n", 884 (long long)base_offset, 885 buffer, report_conflicts, 886 (buffer ? buffer->io.lock.refs : -1)); 887 } 888 } 889 base_offset += HAMMER_BUFSIZE; 890 zone2_offset += HAMMER_BUFSIZE; 891 bytes -= HAMMER_BUFSIZE; 892 } 893 hammer_rel_volume(volume, 0); 894 return (ret_error); 895 } 896 897 /* 898 * Given a referenced and interlocked buffer load/validate the data. 899 * 900 * The buffer interlock will be released on return. If an error is 901 * returned the buffer reference will also be released (and the buffer 902 * pointer will thus be stale). 903 */ 904 static int 905 hammer_load_buffer(hammer_buffer_t buffer, int isnew) 906 { 907 hammer_volume_t volume; 908 int error; 909 910 /* 911 * Load the buffer's on-disk info 912 */ 913 volume = buffer->io.volume; 914 915 if (hammer_debug_io & 0x0004) { 916 hdkprintf("load_buffer %016llx %016llx isnew=%d od=%p\n", 917 (long long)buffer->zoneX_offset, 918 (long long)buffer->zone2_offset, 919 isnew, buffer->ondisk); 920 } 921 922 if (buffer->ondisk == NULL) { 923 /* 924 * Issue the read or generate a new buffer. When reading 925 * the limit argument controls any read-ahead clustering 926 * hammer_io_read() is allowed to do. 927 * 928 * We cannot read-ahead in the large-data zone and we cannot 929 * cross a big-block boundary as the next big-block might 930 * use a different buffer size. 931 */ 932 if (isnew) { 933 error = hammer_io_new(volume->devvp, &buffer->io); 934 } else if ((buffer->zoneX_offset & HAMMER_OFF_ZONE_MASK) == 935 HAMMER_ZONE_LARGE_DATA) { 936 error = hammer_io_read(volume->devvp, &buffer->io, 937 buffer->io.bytes); 938 } else { 939 hammer_off_t limit; 940 941 limit = (buffer->zone2_offset + 942 HAMMER_BIGBLOCK_MASK64) & 943 ~HAMMER_BIGBLOCK_MASK64; 944 limit -= buffer->zone2_offset; 945 error = hammer_io_read(volume->devvp, &buffer->io, 946 limit); 947 } 948 if (error == 0) 949 buffer->ondisk = (void *)buffer->io.bp->b_data; 950 } else if (isnew) { 951 error = hammer_io_new(volume->devvp, &buffer->io); 952 } else { 953 error = 0; 954 } 955 if (error == 0) { 956 hammer_io_advance(&buffer->io); 957 hammer_ref_interlock_done(&buffer->io.lock); 958 } else { 959 hammer_rel_buffer(buffer, 1); 960 } 961 return (error); 962 } 963 964 /* 965 * NOTE: Called from RB_SCAN, must return >= 0 for scan to continue. 966 * This routine is only called during unmount or when a volume is 967 * removed. 968 * 969 * If data != NULL, it specifies a volume whoose buffers should 970 * be unloaded. 971 */ 972 int 973 hammer_unload_buffer(hammer_buffer_t buffer, void *data) 974 { 975 struct hammer_volume *volume = (struct hammer_volume *) data; 976 977 /* 978 * If volume != NULL we are only interested in unloading buffers 979 * associated with a particular volume. 980 */ 981 if (volume != NULL && volume != buffer->io.volume) 982 return 0; 983 984 /* 985 * Clean up the persistent ref ioerror might have on the buffer 986 * and acquire a ref. Expect a 0->1 transition. 987 */ 988 if (buffer->io.ioerror) { 989 hammer_io_clear_error_noassert(&buffer->io); 990 atomic_add_int(&hammer_count_refedbufs, -1); 991 } 992 hammer_ref_interlock_true(&buffer->io.lock); 993 atomic_add_int(&hammer_count_refedbufs, 1); 994 995 /* 996 * We must not flush a dirty buffer to disk on umount. It should 997 * have already been dealt with by the flusher, or we may be in 998 * catastrophic failure. 999 * 1000 * We must set waitdep to ensure that a running buffer is waited 1001 * on and released prior to us trying to unload the volume. 1002 */ 1003 hammer_io_clear_modify(&buffer->io, 1); 1004 hammer_flush_buffer_nodes(buffer); 1005 buffer->io.waitdep = 1; 1006 hammer_rel_buffer(buffer, 1); 1007 return(0); 1008 } 1009 1010 /* 1011 * Reference a buffer that is either already referenced or via a specially 1012 * handled pointer (aka cursor->buffer). 1013 */ 1014 int 1015 hammer_ref_buffer(hammer_buffer_t buffer) 1016 { 1017 hammer_mount_t hmp; 1018 int error; 1019 int locked; 1020 1021 /* 1022 * Acquire a ref, plus the buffer will be interlocked on the 1023 * 0->1 transition. 1024 */ 1025 locked = hammer_ref_interlock(&buffer->io.lock); 1026 hmp = buffer->io.hmp; 1027 1028 /* 1029 * At this point a biodone() will not touch the buffer other then 1030 * incidental bits. However, lose_root can be modified via 1031 * a biodone() interrupt. 1032 * 1033 * No longer loose. lose_root requires the io_token. 1034 */ 1035 if (buffer->io.mod_root == &hmp->lose_root) { 1036 lwkt_gettoken(&hmp->io_token); 1037 if (buffer->io.mod_root == &hmp->lose_root) { 1038 RB_REMOVE(hammer_mod_rb_tree, 1039 buffer->io.mod_root, &buffer->io); 1040 buffer->io.mod_root = NULL; 1041 } 1042 lwkt_reltoken(&hmp->io_token); 1043 } 1044 1045 if (locked) { 1046 atomic_add_int(&hammer_count_refedbufs, 1); 1047 error = hammer_load_buffer(buffer, 0); 1048 /* NOTE: on error the buffer pointer is stale */ 1049 } else { 1050 error = 0; 1051 } 1052 return(error); 1053 } 1054 1055 /* 1056 * Release a reference on the buffer. On the 1->0 transition the 1057 * underlying IO will be released but the data reference is left 1058 * cached. 1059 * 1060 * Only destroy the structure itself if the related buffer cache buffer 1061 * was disassociated from it. This ties the management of the structure 1062 * to the buffer cache subsystem. buffer->ondisk determines whether the 1063 * embedded io is referenced or not. 1064 */ 1065 void 1066 hammer_rel_buffer(hammer_buffer_t buffer, int locked) 1067 { 1068 hammer_volume_t volume; 1069 hammer_mount_t hmp; 1070 struct buf *bp = NULL; 1071 int freeme = 0; 1072 1073 hmp = buffer->io.hmp; 1074 1075 if (hammer_rel_interlock(&buffer->io.lock, locked) == 0) 1076 return; 1077 1078 /* 1079 * hammer_count_refedbufs accounting. Decrement if we are in 1080 * the error path or if CHECK is clear. 1081 * 1082 * If we are not in the error path and CHECK is set the caller 1083 * probably just did a hammer_ref() and didn't account for it, 1084 * so we don't account for the loss here. 1085 */ 1086 if (locked || (buffer->io.lock.refs & HAMMER_REFS_CHECK) == 0) 1087 atomic_add_int(&hammer_count_refedbufs, -1); 1088 1089 /* 1090 * If the caller locked us or the normal released transitions 1091 * from 1->0 (and acquired the lock) attempt to release the 1092 * io. If the called locked us we tell hammer_io_release() 1093 * to flush (which would be the unload or failure path). 1094 */ 1095 bp = hammer_io_release(&buffer->io, locked); 1096 1097 /* 1098 * If the buffer has no bp association and no refs we can destroy 1099 * it. 1100 * 1101 * NOTE: It is impossible for any associated B-Tree nodes to have 1102 * refs if the buffer has no additional refs. 1103 */ 1104 if (buffer->io.bp == NULL && hammer_norefs(&buffer->io.lock)) { 1105 RB_REMOVE(hammer_buf_rb_tree, 1106 &buffer->io.hmp->rb_bufs_root, 1107 buffer); 1108 volume = buffer->io.volume; 1109 buffer->io.volume = NULL; /* sanity */ 1110 hammer_rel_volume(volume, 0); 1111 hammer_io_clear_modlist(&buffer->io); 1112 hammer_flush_buffer_nodes(buffer); 1113 KKASSERT(TAILQ_EMPTY(&buffer->clist)); 1114 freeme = 1; 1115 } 1116 1117 /* 1118 * Cleanup 1119 */ 1120 hammer_rel_interlock_done(&buffer->io.lock, locked); 1121 if (bp) 1122 brelse(bp); 1123 if (freeme) { 1124 --hammer_count_buffers; 1125 kfree(buffer, hmp->m_misc); 1126 } 1127 } 1128 1129 /* 1130 * Access the filesystem buffer containing the specified hammer offset. 1131 * buf_offset is a conglomeration of the volume number and vol_buf_beg 1132 * relative buffer offset. It must also have bit 55 set to be valid. 1133 * (see hammer_off_t in hammer_disk.h). 1134 * 1135 * Any prior buffer in *bufferp will be released and replaced by the 1136 * requested buffer. 1137 * 1138 * NOTE: The buffer is indexed via its zoneX_offset but we allow the 1139 * passed cached *bufferp to match against either zoneX or zone2. 1140 */ 1141 static __inline 1142 void * 1143 _hammer_bread(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1144 int isnew, int *errorp, struct hammer_buffer **bufferp) 1145 { 1146 hammer_buffer_t buffer; 1147 int32_t xoff = (int32_t)buf_offset & HAMMER_BUFMASK; 1148 1149 buf_offset &= ~HAMMER_BUFMASK64; 1150 KKASSERT((buf_offset & HAMMER_OFF_ZONE_MASK) != 0); 1151 1152 buffer = *bufferp; 1153 if (buffer == NULL || (buffer->zone2_offset != buf_offset && 1154 buffer->zoneX_offset != buf_offset)) { 1155 if (buffer) 1156 hammer_rel_buffer(buffer, 0); 1157 buffer = hammer_get_buffer(hmp, buf_offset, bytes, isnew, errorp); 1158 *bufferp = buffer; 1159 } else { 1160 *errorp = 0; 1161 } 1162 1163 /* 1164 * Return a pointer to the buffer data. 1165 */ 1166 if (buffer == NULL) 1167 return(NULL); 1168 else 1169 return((char *)buffer->ondisk + xoff); 1170 } 1171 1172 void * 1173 hammer_bread(hammer_mount_t hmp, hammer_off_t buf_offset, 1174 int *errorp, struct hammer_buffer **bufferp) 1175 { 1176 return(_hammer_bread(hmp, buf_offset, HAMMER_BUFSIZE, 0, errorp, bufferp)); 1177 } 1178 1179 void * 1180 hammer_bread_ext(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1181 int *errorp, struct hammer_buffer **bufferp) 1182 { 1183 bytes = (bytes + HAMMER_BUFMASK) & ~HAMMER_BUFMASK; 1184 return(_hammer_bread(hmp, buf_offset, bytes, 0, errorp, bufferp)); 1185 } 1186 1187 /* 1188 * Access the filesystem buffer containing the specified hammer offset. 1189 * No disk read operation occurs. The result buffer may contain garbage. 1190 * 1191 * Any prior buffer in *bufferp will be released and replaced by the 1192 * requested buffer. 1193 * 1194 * This function marks the buffer dirty but does not increment its 1195 * modify_refs count. 1196 */ 1197 void * 1198 hammer_bnew(hammer_mount_t hmp, hammer_off_t buf_offset, 1199 int *errorp, struct hammer_buffer **bufferp) 1200 { 1201 return(_hammer_bread(hmp, buf_offset, HAMMER_BUFSIZE, 1, errorp, bufferp)); 1202 } 1203 1204 void * 1205 hammer_bnew_ext(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1206 int *errorp, struct hammer_buffer **bufferp) 1207 { 1208 bytes = (bytes + HAMMER_BUFMASK) & ~HAMMER_BUFMASK; 1209 return(_hammer_bread(hmp, buf_offset, bytes, 1, errorp, bufferp)); 1210 } 1211 1212 /************************************************************************ 1213 * NODES * 1214 ************************************************************************ 1215 * 1216 * Manage B-Tree nodes. B-Tree nodes represent the primary indexing 1217 * method used by the HAMMER filesystem. 1218 * 1219 * Unlike other HAMMER structures, a hammer_node can be PASSIVELY 1220 * associated with its buffer, and will only referenced the buffer while 1221 * the node itself is referenced. 1222 * 1223 * A hammer_node can also be passively associated with other HAMMER 1224 * structures, such as inodes, while retaining 0 references. These 1225 * associations can be cleared backwards using a pointer-to-pointer in 1226 * the hammer_node. 1227 * 1228 * This allows the HAMMER implementation to cache hammer_nodes long-term 1229 * and short-cut a great deal of the infrastructure's complexity. In 1230 * most cases a cached node can be reacquired without having to dip into 1231 * the B-Tree. 1232 */ 1233 hammer_node_t 1234 hammer_get_node(hammer_transaction_t trans, hammer_off_t node_offset, 1235 int isnew, int *errorp) 1236 { 1237 hammer_mount_t hmp = trans->hmp; 1238 hammer_node_t node; 1239 int doload; 1240 1241 KKASSERT((node_offset & HAMMER_OFF_ZONE_MASK) == HAMMER_ZONE_BTREE); 1242 1243 /* 1244 * Locate the structure, allocating one if necessary. 1245 */ 1246 again: 1247 node = RB_LOOKUP(hammer_nod_rb_tree, &hmp->rb_nods_root, node_offset); 1248 if (node == NULL) { 1249 ++hammer_count_nodes; 1250 node = kmalloc(sizeof(*node), hmp->m_misc, M_WAITOK|M_ZERO|M_USE_RESERVE); 1251 node->node_offset = node_offset; 1252 node->hmp = hmp; 1253 TAILQ_INIT(&node->cursor_list); 1254 TAILQ_INIT(&node->cache_list); 1255 if (RB_INSERT(hammer_nod_rb_tree, &hmp->rb_nods_root, node)) { 1256 --hammer_count_nodes; 1257 kfree(node, hmp->m_misc); 1258 goto again; 1259 } 1260 doload = hammer_ref_interlock_true(&node->lock); 1261 } else { 1262 doload = hammer_ref_interlock(&node->lock); 1263 } 1264 if (doload) { 1265 *errorp = hammer_load_node(trans, node, isnew); 1266 trans->flags |= HAMMER_TRANSF_DIDIO; 1267 if (*errorp) 1268 node = NULL; 1269 } else { 1270 KKASSERT(node->ondisk); 1271 *errorp = 0; 1272 hammer_io_advance(&node->buffer->io); 1273 } 1274 return(node); 1275 } 1276 1277 /* 1278 * Reference an already-referenced node. 0->1 transitions should assert 1279 * so we do not have to deal with hammer_ref() setting CHECK. 1280 */ 1281 void 1282 hammer_ref_node(hammer_node_t node) 1283 { 1284 KKASSERT(hammer_isactive(&node->lock) && node->ondisk != NULL); 1285 hammer_ref(&node->lock); 1286 } 1287 1288 /* 1289 * Load a node's on-disk data reference. Called with the node referenced 1290 * and interlocked. 1291 * 1292 * On return the node interlock will be unlocked. If a non-zero error code 1293 * is returned the node will also be dereferenced (and the caller's pointer 1294 * will be stale). 1295 */ 1296 static int 1297 hammer_load_node(hammer_transaction_t trans, hammer_node_t node, int isnew) 1298 { 1299 hammer_buffer_t buffer; 1300 hammer_off_t buf_offset; 1301 int error; 1302 1303 error = 0; 1304 if (node->ondisk == NULL) { 1305 /* 1306 * This is a little confusing but the jist is that 1307 * node->buffer determines whether the node is on 1308 * the buffer's clist and node->ondisk determines 1309 * whether the buffer is referenced. 1310 * 1311 * We could be racing a buffer release, in which case 1312 * node->buffer may become NULL while we are blocked 1313 * referencing the buffer. 1314 */ 1315 if ((buffer = node->buffer) != NULL) { 1316 error = hammer_ref_buffer(buffer); 1317 if (error == 0 && node->buffer == NULL) { 1318 TAILQ_INSERT_TAIL(&buffer->clist, node, entry); 1319 node->buffer = buffer; 1320 } 1321 } else { 1322 buf_offset = node->node_offset & ~HAMMER_BUFMASK64; 1323 buffer = hammer_get_buffer(node->hmp, buf_offset, 1324 HAMMER_BUFSIZE, 0, &error); 1325 if (buffer) { 1326 KKASSERT(error == 0); 1327 TAILQ_INSERT_TAIL(&buffer->clist, node, entry); 1328 node->buffer = buffer; 1329 } 1330 } 1331 if (error) 1332 goto failed; 1333 node->ondisk = (void *)((char *)buffer->ondisk + 1334 (node->node_offset & HAMMER_BUFMASK)); 1335 1336 /* 1337 * Check CRC. NOTE: Neither flag is set and the CRC is not 1338 * generated on new B-Tree nodes. 1339 */ 1340 if (isnew == 0 && 1341 (node->flags & HAMMER_NODE_CRCANY) == 0) { 1342 if (hammer_crc_test_btree(node->ondisk) == 0) { 1343 hdkprintf("CRC B-TREE NODE @ %016llx/%lu FAILED\n", 1344 (long long)node->node_offset, 1345 sizeof(*node->ondisk)); 1346 if (hammer_debug_critical) 1347 Debugger("CRC FAILED: B-TREE NODE"); 1348 node->flags |= HAMMER_NODE_CRCBAD; 1349 } else { 1350 node->flags |= HAMMER_NODE_CRCGOOD; 1351 } 1352 } 1353 } 1354 if (node->flags & HAMMER_NODE_CRCBAD) { 1355 if (trans->flags & HAMMER_TRANSF_CRCDOM) 1356 error = EDOM; 1357 else 1358 error = EIO; 1359 } 1360 failed: 1361 if (error) { 1362 _hammer_rel_node(node, 1); 1363 } else { 1364 hammer_ref_interlock_done(&node->lock); 1365 } 1366 return (error); 1367 } 1368 1369 /* 1370 * Safely reference a node, interlock against flushes via the IO subsystem. 1371 */ 1372 hammer_node_t 1373 hammer_ref_node_safe(hammer_transaction_t trans, hammer_node_cache_t cache, 1374 int *errorp) 1375 { 1376 hammer_node_t node; 1377 int doload; 1378 1379 node = cache->node; 1380 if (node != NULL) { 1381 doload = hammer_ref_interlock(&node->lock); 1382 if (doload) { 1383 *errorp = hammer_load_node(trans, node, 0); 1384 if (*errorp) 1385 node = NULL; 1386 } else { 1387 KKASSERT(node->ondisk); 1388 if (node->flags & HAMMER_NODE_CRCBAD) { 1389 if (trans->flags & HAMMER_TRANSF_CRCDOM) 1390 *errorp = EDOM; 1391 else 1392 *errorp = EIO; 1393 _hammer_rel_node(node, 0); 1394 node = NULL; 1395 } else { 1396 *errorp = 0; 1397 } 1398 } 1399 } else { 1400 *errorp = ENOENT; 1401 } 1402 return(node); 1403 } 1404 1405 /* 1406 * Release a hammer_node. On the last release the node dereferences 1407 * its underlying buffer and may or may not be destroyed. 1408 * 1409 * If locked is non-zero the passed node has been interlocked by the 1410 * caller and we are in the failure/unload path, otherwise it has not and 1411 * we are doing a normal release. 1412 * 1413 * This function will dispose of the interlock and the reference. 1414 * On return the node pointer is stale. 1415 */ 1416 void 1417 _hammer_rel_node(hammer_node_t node, int locked) 1418 { 1419 hammer_buffer_t buffer; 1420 1421 /* 1422 * Deref the node. If this isn't the 1->0 transition we're basically 1423 * done. If locked is non-zero this function will just deref the 1424 * locked node and return 1, otherwise it will deref the locked 1425 * node and either lock and return 1 on the 1->0 transition or 1426 * not lock and return 0. 1427 */ 1428 if (hammer_rel_interlock(&node->lock, locked) == 0) 1429 return; 1430 1431 /* 1432 * Either locked was non-zero and we are interlocked, or the 1433 * hammer_rel_interlock() call returned non-zero and we are 1434 * interlocked. 1435 * 1436 * The ref-count must still be decremented if locked != 0 so 1437 * the cleanup required still varies a bit. 1438 * 1439 * hammer_flush_node() when called with 1 or 2 will dispose of 1440 * the lock and possible ref-count. 1441 */ 1442 if (node->ondisk == NULL) { 1443 hammer_flush_node(node, locked + 1); 1444 /* node is stale now */ 1445 return; 1446 } 1447 1448 /* 1449 * Do not disassociate the node from the buffer if it represents 1450 * a modified B-Tree node that still needs its crc to be generated. 1451 */ 1452 if (node->flags & HAMMER_NODE_NEEDSCRC) { 1453 hammer_rel_interlock_done(&node->lock, locked); 1454 return; 1455 } 1456 1457 /* 1458 * Do final cleanups and then either destroy the node and leave it 1459 * passively cached. The buffer reference is removed regardless. 1460 */ 1461 buffer = node->buffer; 1462 node->ondisk = NULL; 1463 1464 if ((node->flags & HAMMER_NODE_FLUSH) == 0) { 1465 /* 1466 * Normal release. 1467 */ 1468 hammer_rel_interlock_done(&node->lock, locked); 1469 } else { 1470 /* 1471 * Destroy the node. 1472 */ 1473 hammer_flush_node(node, locked + 1); 1474 /* node is stale */ 1475 1476 } 1477 hammer_rel_buffer(buffer, 0); 1478 } 1479 1480 void 1481 hammer_rel_node(hammer_node_t node) 1482 { 1483 _hammer_rel_node(node, 0); 1484 } 1485 1486 /* 1487 * Free space on-media associated with a B-Tree node. 1488 */ 1489 void 1490 hammer_delete_node(hammer_transaction_t trans, hammer_node_t node) 1491 { 1492 KKASSERT((node->flags & HAMMER_NODE_DELETED) == 0); 1493 node->flags |= HAMMER_NODE_DELETED; 1494 hammer_blockmap_free(trans, node->node_offset, sizeof(*node->ondisk)); 1495 } 1496 1497 /* 1498 * Passively cache a referenced hammer_node. The caller may release 1499 * the node on return. 1500 */ 1501 void 1502 hammer_cache_node(hammer_node_cache_t cache, hammer_node_t node) 1503 { 1504 /* 1505 * If the node doesn't exist, or is being deleted, don't cache it! 1506 * 1507 * The node can only ever be NULL in the I/O failure path. 1508 */ 1509 if (node == NULL || (node->flags & HAMMER_NODE_DELETED)) 1510 return; 1511 if (cache->node == node) 1512 return; 1513 while (cache->node) 1514 hammer_uncache_node(cache); 1515 if (node->flags & HAMMER_NODE_DELETED) 1516 return; 1517 cache->node = node; 1518 TAILQ_INSERT_TAIL(&node->cache_list, cache, entry); 1519 } 1520 1521 void 1522 hammer_uncache_node(hammer_node_cache_t cache) 1523 { 1524 hammer_node_t node; 1525 1526 if ((node = cache->node) != NULL) { 1527 TAILQ_REMOVE(&node->cache_list, cache, entry); 1528 cache->node = NULL; 1529 if (TAILQ_EMPTY(&node->cache_list)) 1530 hammer_flush_node(node, 0); 1531 } 1532 } 1533 1534 /* 1535 * Remove a node's cache references and destroy the node if it has no 1536 * other references or backing store. 1537 * 1538 * locked == 0 Normal unlocked operation 1539 * locked == 1 Call hammer_rel_interlock_done(..., 0); 1540 * locked == 2 Call hammer_rel_interlock_done(..., 1); 1541 * 1542 * XXX for now this isn't even close to being MPSAFE so the refs check 1543 * is sufficient. 1544 */ 1545 void 1546 hammer_flush_node(hammer_node_t node, int locked) 1547 { 1548 hammer_node_cache_t cache; 1549 hammer_buffer_t buffer; 1550 hammer_mount_t hmp = node->hmp; 1551 int dofree; 1552 1553 while ((cache = TAILQ_FIRST(&node->cache_list)) != NULL) { 1554 TAILQ_REMOVE(&node->cache_list, cache, entry); 1555 cache->node = NULL; 1556 } 1557 1558 /* 1559 * NOTE: refs is predisposed if another thread is blocking and 1560 * will be larger than 0 in that case. We aren't MPSAFE 1561 * here. 1562 */ 1563 if (node->ondisk == NULL && hammer_norefs(&node->lock)) { 1564 KKASSERT((node->flags & HAMMER_NODE_NEEDSCRC) == 0); 1565 RB_REMOVE(hammer_nod_rb_tree, &node->hmp->rb_nods_root, node); 1566 if ((buffer = node->buffer) != NULL) { 1567 node->buffer = NULL; 1568 TAILQ_REMOVE(&buffer->clist, node, entry); 1569 /* buffer is unreferenced because ondisk is NULL */ 1570 } 1571 dofree = 1; 1572 } else { 1573 dofree = 0; 1574 } 1575 1576 /* 1577 * Deal with the interlock if locked == 1 or locked == 2. 1578 */ 1579 if (locked) 1580 hammer_rel_interlock_done(&node->lock, locked - 1); 1581 1582 /* 1583 * Destroy if requested 1584 */ 1585 if (dofree) { 1586 --hammer_count_nodes; 1587 kfree(node, hmp->m_misc); 1588 } 1589 } 1590 1591 /* 1592 * Flush passively cached B-Tree nodes associated with this buffer. 1593 * This is only called when the buffer is about to be destroyed, so 1594 * none of the nodes should have any references. The buffer is locked. 1595 * 1596 * We may be interlocked with the buffer. 1597 */ 1598 void 1599 hammer_flush_buffer_nodes(hammer_buffer_t buffer) 1600 { 1601 hammer_node_t node; 1602 1603 while ((node = TAILQ_FIRST(&buffer->clist)) != NULL) { 1604 KKASSERT(node->ondisk == NULL); 1605 KKASSERT((node->flags & HAMMER_NODE_NEEDSCRC) == 0); 1606 1607 if (hammer_try_interlock_norefs(&node->lock)) { 1608 hammer_ref(&node->lock); 1609 node->flags |= HAMMER_NODE_FLUSH; 1610 _hammer_rel_node(node, 1); 1611 } else { 1612 KKASSERT(node->buffer != NULL); 1613 buffer = node->buffer; 1614 node->buffer = NULL; 1615 TAILQ_REMOVE(&buffer->clist, node, entry); 1616 /* buffer is unreferenced because ondisk is NULL */ 1617 } 1618 } 1619 } 1620 1621 1622 /************************************************************************ 1623 * ALLOCATORS * 1624 ************************************************************************/ 1625 1626 /* 1627 * Allocate a B-Tree node. 1628 */ 1629 hammer_node_t 1630 hammer_alloc_btree(hammer_transaction_t trans, hammer_off_t hint, int *errorp) 1631 { 1632 hammer_buffer_t buffer = NULL; 1633 hammer_node_t node = NULL; 1634 hammer_off_t node_offset; 1635 1636 node_offset = hammer_blockmap_alloc(trans, HAMMER_ZONE_BTREE_INDEX, 1637 sizeof(struct hammer_node_ondisk), 1638 hint, errorp); 1639 if (*errorp == 0) { 1640 node = hammer_get_node(trans, node_offset, 1, errorp); 1641 hammer_modify_node_noundo(trans, node); 1642 bzero(node->ondisk, sizeof(*node->ondisk)); 1643 hammer_modify_node_done(node); 1644 } 1645 if (buffer) 1646 hammer_rel_buffer(buffer, 0); 1647 return(node); 1648 } 1649 1650 /* 1651 * Allocate data. If the address of a data buffer is supplied then 1652 * any prior non-NULL *data_bufferp will be released and *data_bufferp 1653 * will be set to the related buffer. The caller must release it when 1654 * finally done. The initial *data_bufferp should be set to NULL by 1655 * the caller. 1656 * 1657 * The caller is responsible for making hammer_modify*() calls on the 1658 * *data_bufferp. 1659 */ 1660 void * 1661 hammer_alloc_data(hammer_transaction_t trans, int32_t data_len, 1662 uint16_t rec_type, hammer_off_t *data_offsetp, 1663 struct hammer_buffer **data_bufferp, 1664 hammer_off_t hint, int *errorp) 1665 { 1666 void *data; 1667 int zone; 1668 1669 /* 1670 * Allocate data directly from blockmap. 1671 */ 1672 if (data_len) { 1673 switch(rec_type) { 1674 case HAMMER_RECTYPE_INODE: 1675 case HAMMER_RECTYPE_DIRENTRY: 1676 case HAMMER_RECTYPE_EXT: 1677 case HAMMER_RECTYPE_FIX: 1678 case HAMMER_RECTYPE_PFS: 1679 case HAMMER_RECTYPE_SNAPSHOT: 1680 case HAMMER_RECTYPE_CONFIG: 1681 zone = HAMMER_ZONE_META_INDEX; 1682 break; 1683 case HAMMER_RECTYPE_DATA: 1684 case HAMMER_RECTYPE_DB: 1685 /* 1686 * Only mirror-write comes here. 1687 * Regular allocation path uses blockmap reservation. 1688 */ 1689 zone = hammer_data_zone_index(data_len); 1690 if (zone == HAMMER_ZONE_LARGE_DATA_INDEX) { 1691 /* round up */ 1692 data_len = (data_len + HAMMER_BUFMASK) & 1693 ~HAMMER_BUFMASK; 1694 } 1695 break; 1696 default: 1697 hpanic("rec_type %04x unknown", rec_type); 1698 zone = HAMMER_ZONE_UNAVAIL_INDEX; /* NOT REACHED */ 1699 break; 1700 } 1701 *data_offsetp = hammer_blockmap_alloc(trans, zone, data_len, 1702 hint, errorp); 1703 } else { 1704 *data_offsetp = 0; 1705 } 1706 1707 data = NULL; 1708 if (*errorp == 0 && data_bufferp && data_len) 1709 data = hammer_bread_ext(trans->hmp, *data_offsetp, data_len, 1710 errorp, data_bufferp); 1711 return(data); 1712 } 1713 1714 /* 1715 * Sync dirty buffers to the media and clean-up any loose ends. 1716 * 1717 * These functions do not start the flusher going, they simply 1718 * queue everything up to the flusher. 1719 */ 1720 static int hammer_sync_scan2(struct mount *mp, struct vnode *vp, void *data); 1721 1722 struct hammer_sync_info { 1723 int error; 1724 }; 1725 1726 int 1727 hammer_queue_inodes_flusher(hammer_mount_t hmp, int waitfor) 1728 { 1729 struct hammer_sync_info info; 1730 1731 info.error = 0; 1732 if (waitfor == MNT_WAIT) { 1733 vsyncscan(hmp->mp, VMSC_GETVP | VMSC_ONEPASS, 1734 hammer_sync_scan2, &info); 1735 } else { 1736 vsyncscan(hmp->mp, VMSC_GETVP | VMSC_ONEPASS | VMSC_NOWAIT, 1737 hammer_sync_scan2, &info); 1738 } 1739 return(info.error); 1740 } 1741 1742 /* 1743 * Filesystem sync. If doing a synchronous sync make a second pass on 1744 * the vnodes in case any were already flushing during the first pass, 1745 * and activate the flusher twice (the second time brings the UNDO FIFO's 1746 * start position up to the end position after the first call). 1747 * 1748 * If doing a lazy sync make just one pass on the vnode list, ignoring 1749 * any new vnodes added to the list while the sync is in progress. 1750 */ 1751 int 1752 hammer_sync_hmp(hammer_mount_t hmp, int waitfor) 1753 { 1754 struct hammer_sync_info info; 1755 int flags; 1756 1757 flags = VMSC_GETVP; 1758 if (waitfor & MNT_LAZY) 1759 flags |= VMSC_ONEPASS; 1760 1761 info.error = 0; 1762 vsyncscan(hmp->mp, flags | VMSC_NOWAIT, hammer_sync_scan2, &info); 1763 1764 if (info.error == 0 && (waitfor & MNT_WAIT)) { 1765 vsyncscan(hmp->mp, flags, hammer_sync_scan2, &info); 1766 } 1767 if (waitfor == MNT_WAIT) { 1768 hammer_flusher_sync(hmp); 1769 hammer_flusher_sync(hmp); 1770 } else { 1771 hammer_flusher_async(hmp, NULL); 1772 hammer_flusher_async(hmp, NULL); 1773 } 1774 return(info.error); 1775 } 1776 1777 static int 1778 hammer_sync_scan2(struct mount *mp, struct vnode *vp, void *data) 1779 { 1780 struct hammer_sync_info *info = data; 1781 struct hammer_inode *ip; 1782 int error; 1783 1784 ip = VTOI(vp); 1785 if (ip == NULL) 1786 return(0); 1787 if (vp->v_type == VNON || vp->v_type == VBAD) { 1788 vclrisdirty(vp); 1789 return(0); 1790 } 1791 if ((ip->flags & HAMMER_INODE_MODMASK) == 0 && 1792 RB_EMPTY(&vp->v_rbdirty_tree)) { 1793 vclrisdirty(vp); 1794 return(0); 1795 } 1796 error = VOP_FSYNC(vp, MNT_NOWAIT, 0); 1797 if (error) 1798 info->error = error; 1799 return(0); 1800 } 1801