1 /* 2 * Copyright (c) 2007-2008 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * $DragonFly: src/sys/vfs/hammer/hammer_ondisk.c,v 1.76 2008/08/29 20:19:08 dillon Exp $ 35 */ 36 /* 37 * Manage HAMMER's on-disk structures. These routines are primarily 38 * responsible for interfacing with the kernel's I/O subsystem and for 39 * managing in-memory structures. 40 */ 41 42 #include "hammer.h" 43 #include <sys/fcntl.h> 44 #include <sys/nlookup.h> 45 #include <sys/buf.h> 46 #include <sys/buf2.h> 47 48 static void hammer_free_volume(hammer_volume_t volume); 49 static int hammer_load_volume(hammer_volume_t volume); 50 static int hammer_load_buffer(hammer_buffer_t buffer, int isnew); 51 static int hammer_load_node(hammer_transaction_t trans, 52 hammer_node_t node, int isnew); 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, get_volume() will 101 * not load a new volume. 102 * 103 * Calls made to hammer_load_volume() or single-threaded 104 */ 105 int 106 hammer_install_volume(struct hammer_mount *hmp, const char *volname, 107 struct vnode *devvp) 108 { 109 struct mount *mp; 110 hammer_volume_t volume; 111 struct hammer_volume_ondisk *ondisk; 112 struct nlookupdata nd; 113 struct buf *bp = NULL; 114 int error; 115 int ronly; 116 int setmp = 0; 117 118 mp = hmp->mp; 119 ronly = ((mp->mnt_flag & MNT_RDONLY) ? 1 : 0); 120 121 /* 122 * Allocate a volume structure 123 */ 124 ++hammer_count_volumes; 125 volume = kmalloc(sizeof(*volume), hmp->m_misc, M_WAITOK|M_ZERO); 126 volume->vol_name = kstrdup(volname, hmp->m_misc); 127 volume->io.hmp = hmp; /* bootstrap */ 128 hammer_io_init(&volume->io, volume, HAMMER_STRUCTURE_VOLUME); 129 volume->io.offset = 0LL; 130 volume->io.bytes = HAMMER_BUFSIZE; 131 132 /* 133 * Get the device vnode 134 */ 135 if (devvp == NULL) { 136 error = nlookup_init(&nd, volume->vol_name, UIO_SYSSPACE, NLC_FOLLOW); 137 if (error == 0) 138 error = nlookup(&nd); 139 if (error == 0) 140 error = cache_vref(&nd.nl_nch, nd.nl_cred, &volume->devvp); 141 nlookup_done(&nd); 142 } else { 143 error = 0; 144 volume->devvp = devvp; 145 } 146 147 if (error == 0) { 148 if (vn_isdisk(volume->devvp, &error)) { 149 error = vfs_mountedon(volume->devvp); 150 } 151 } 152 if (error == 0 && 153 count_udev(volume->devvp->v_umajor, volume->devvp->v_uminor) > 0) { 154 error = EBUSY; 155 } 156 if (error == 0) { 157 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 158 error = vinvalbuf(volume->devvp, V_SAVE, 0, 0); 159 if (error == 0) { 160 error = VOP_OPEN(volume->devvp, 161 (ronly ? FREAD : FREAD|FWRITE), 162 FSCRED, NULL); 163 } 164 vn_unlock(volume->devvp); 165 } 166 if (error) { 167 hammer_free_volume(volume); 168 return(error); 169 } 170 volume->devvp->v_rdev->si_mountpoint = mp; 171 setmp = 1; 172 173 /* 174 * Extract the volume number from the volume header and do various 175 * sanity checks. 176 */ 177 error = bread(volume->devvp, 0LL, HAMMER_BUFSIZE, &bp); 178 if (error) 179 goto late_failure; 180 ondisk = (void *)bp->b_data; 181 if (ondisk->vol_signature != HAMMER_FSBUF_VOLUME) { 182 kprintf("hammer_mount: volume %s has an invalid header\n", 183 volume->vol_name); 184 error = EFTYPE; 185 goto late_failure; 186 } 187 volume->vol_no = ondisk->vol_no; 188 volume->buffer_base = ondisk->vol_buf_beg; 189 volume->vol_flags = ondisk->vol_flags; 190 volume->nblocks = ondisk->vol_nblocks; 191 volume->maxbuf_off = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 192 ondisk->vol_buf_end - ondisk->vol_buf_beg); 193 volume->maxraw_off = ondisk->vol_buf_end; 194 195 if (RB_EMPTY(&hmp->rb_vols_root)) { 196 hmp->fsid = ondisk->vol_fsid; 197 } else if (bcmp(&hmp->fsid, &ondisk->vol_fsid, sizeof(uuid_t))) { 198 kprintf("hammer_mount: volume %s's fsid does not match " 199 "other volumes\n", volume->vol_name); 200 error = EFTYPE; 201 goto late_failure; 202 } 203 204 /* 205 * Insert the volume structure into the red-black tree. 206 */ 207 if (RB_INSERT(hammer_vol_rb_tree, &hmp->rb_vols_root, volume)) { 208 kprintf("hammer_mount: volume %s has a duplicate vol_no %d\n", 209 volume->vol_name, volume->vol_no); 210 error = EEXIST; 211 } 212 213 /* 214 * Set the root volume . HAMMER special cases rootvol the structure. 215 * We do not hold a ref because this would prevent related I/O 216 * from being flushed. 217 */ 218 if (error == 0 && ondisk->vol_rootvol == ondisk->vol_no) { 219 hmp->rootvol = volume; 220 hmp->nvolumes = ondisk->vol_count; 221 if (bp) { 222 brelse(bp); 223 bp = NULL; 224 } 225 hmp->mp->mnt_stat.f_blocks += ondisk->vol0_stat_bigblocks * 226 (HAMMER_LARGEBLOCK_SIZE / HAMMER_BUFSIZE); 227 hmp->mp->mnt_vstat.f_blocks += ondisk->vol0_stat_bigblocks * 228 (HAMMER_LARGEBLOCK_SIZE / HAMMER_BUFSIZE); 229 } 230 late_failure: 231 if (bp) 232 brelse(bp); 233 if (error) { 234 /*vinvalbuf(volume->devvp, V_SAVE, 0, 0);*/ 235 if (setmp) 236 volume->devvp->v_rdev->si_mountpoint = NULL; 237 VOP_CLOSE(volume->devvp, ronly ? FREAD : FREAD|FWRITE); 238 hammer_free_volume(volume); 239 } 240 return (error); 241 } 242 243 /* 244 * This is called for each volume when updating the mount point from 245 * read-write to read-only or vise-versa. 246 */ 247 int 248 hammer_adjust_volume_mode(hammer_volume_t volume, void *data __unused) 249 { 250 if (volume->devvp) { 251 vn_lock(volume->devvp, LK_EXCLUSIVE | LK_RETRY); 252 if (volume->io.hmp->ronly) { 253 /* do not call vinvalbuf */ 254 VOP_OPEN(volume->devvp, FREAD, FSCRED, NULL); 255 VOP_CLOSE(volume->devvp, FREAD|FWRITE); 256 } else { 257 /* do not call vinvalbuf */ 258 VOP_OPEN(volume->devvp, FREAD|FWRITE, FSCRED, NULL); 259 VOP_CLOSE(volume->devvp, FREAD); 260 } 261 vn_unlock(volume->devvp); 262 } 263 return(0); 264 } 265 266 /* 267 * Unload and free a HAMMER volume. Must return >= 0 to continue scan 268 * so returns -1 on failure. 269 */ 270 int 271 hammer_unload_volume(hammer_volume_t volume, void *data __unused) 272 { 273 hammer_mount_t hmp = volume->io.hmp; 274 int ronly = ((hmp->mp->mnt_flag & MNT_RDONLY) ? 1 : 0); 275 struct buf *bp; 276 277 /* 278 * Clean up the root volume pointer, which is held unlocked in hmp. 279 */ 280 if (hmp->rootvol == volume) 281 hmp->rootvol = NULL; 282 283 /* 284 * We must not flush a dirty buffer to disk on umount. It should 285 * have already been dealt with by the flusher, or we may be in 286 * catastrophic failure. 287 */ 288 hammer_io_clear_modify(&volume->io, 1); 289 volume->io.waitdep = 1; 290 bp = hammer_io_release(&volume->io, 1); 291 292 /* 293 * Clean up the persistent ref ioerror might have on the volume 294 */ 295 if (volume->io.ioerror) { 296 volume->io.ioerror = 0; 297 hammer_unref(&volume->io.lock); 298 } 299 300 /* 301 * There should be no references on the volume, no clusters, and 302 * no super-clusters. 303 */ 304 KKASSERT(volume->io.lock.refs == 0); 305 if (bp) 306 brelse(bp); 307 308 volume->ondisk = NULL; 309 if (volume->devvp) { 310 if (volume->devvp->v_rdev && 311 volume->devvp->v_rdev->si_mountpoint == hmp->mp 312 ) { 313 volume->devvp->v_rdev->si_mountpoint = NULL; 314 } 315 if (ronly) { 316 /* 317 * Make sure we don't sync anything to disk if we 318 * are in read-only mode (1) or critically-errored 319 * (2). Note that there may be dirty buffers in 320 * normal read-only mode from crash recovery. 321 */ 322 vinvalbuf(volume->devvp, 0, 0, 0); 323 VOP_CLOSE(volume->devvp, FREAD); 324 } else { 325 /* 326 * Normal termination, save any dirty buffers 327 * (XXX there really shouldn't be any). 328 */ 329 vinvalbuf(volume->devvp, V_SAVE, 0, 0); 330 VOP_CLOSE(volume->devvp, FREAD|FWRITE); 331 } 332 } 333 334 /* 335 * Destroy the structure 336 */ 337 RB_REMOVE(hammer_vol_rb_tree, &hmp->rb_vols_root, volume); 338 hammer_free_volume(volume); 339 return(0); 340 } 341 342 static 343 void 344 hammer_free_volume(hammer_volume_t volume) 345 { 346 hammer_mount_t hmp = volume->io.hmp; 347 348 if (volume->vol_name) { 349 kfree(volume->vol_name, hmp->m_misc); 350 volume->vol_name = NULL; 351 } 352 if (volume->devvp) { 353 vrele(volume->devvp); 354 volume->devvp = NULL; 355 } 356 --hammer_count_volumes; 357 kfree(volume, hmp->m_misc); 358 } 359 360 /* 361 * Get a HAMMER volume. The volume must already exist. 362 */ 363 hammer_volume_t 364 hammer_get_volume(struct hammer_mount *hmp, int32_t vol_no, int *errorp) 365 { 366 struct hammer_volume *volume; 367 368 /* 369 * Locate the volume structure 370 */ 371 volume = RB_LOOKUP(hammer_vol_rb_tree, &hmp->rb_vols_root, vol_no); 372 if (volume == NULL) { 373 *errorp = ENOENT; 374 return(NULL); 375 } 376 hammer_ref(&volume->io.lock); 377 378 /* 379 * Deal with on-disk info 380 */ 381 if (volume->ondisk == NULL || volume->io.loading) { 382 *errorp = hammer_load_volume(volume); 383 if (*errorp) { 384 hammer_rel_volume(volume, 1); 385 volume = NULL; 386 } 387 } else { 388 *errorp = 0; 389 } 390 return(volume); 391 } 392 393 int 394 hammer_ref_volume(hammer_volume_t volume) 395 { 396 int error; 397 398 hammer_ref(&volume->io.lock); 399 400 /* 401 * Deal with on-disk info 402 */ 403 if (volume->ondisk == NULL || volume->io.loading) { 404 error = hammer_load_volume(volume); 405 if (error) 406 hammer_rel_volume(volume, 1); 407 } else { 408 error = 0; 409 } 410 return (error); 411 } 412 413 hammer_volume_t 414 hammer_get_root_volume(struct hammer_mount *hmp, int *errorp) 415 { 416 hammer_volume_t volume; 417 418 volume = hmp->rootvol; 419 KKASSERT(volume != NULL); 420 hammer_ref(&volume->io.lock); 421 422 /* 423 * Deal with on-disk info 424 */ 425 if (volume->ondisk == NULL || volume->io.loading) { 426 *errorp = hammer_load_volume(volume); 427 if (*errorp) { 428 hammer_rel_volume(volume, 1); 429 volume = NULL; 430 } 431 } else { 432 *errorp = 0; 433 } 434 return (volume); 435 } 436 437 /* 438 * Load a volume's on-disk information. The volume must be referenced and 439 * not locked. We temporarily acquire an exclusive lock to interlock 440 * against releases or multiple get's. 441 */ 442 static int 443 hammer_load_volume(hammer_volume_t volume) 444 { 445 int error; 446 447 ++volume->io.loading; 448 hammer_lock_ex(&volume->io.lock); 449 450 if (volume->ondisk == NULL) { 451 error = hammer_io_read(volume->devvp, &volume->io, 452 volume->maxraw_off); 453 if (error == 0) 454 volume->ondisk = (void *)volume->io.bp->b_data; 455 } else { 456 error = 0; 457 } 458 --volume->io.loading; 459 hammer_unlock(&volume->io.lock); 460 return(error); 461 } 462 463 /* 464 * Release a volume. Call hammer_io_release on the last reference. We have 465 * to acquire an exclusive lock to interlock against volume->ondisk tests 466 * in hammer_load_volume(), and hammer_io_release() also expects an exclusive 467 * lock to be held. 468 * 469 * Volumes are not unloaded from memory during normal operation. 470 */ 471 void 472 hammer_rel_volume(hammer_volume_t volume, int flush) 473 { 474 struct buf *bp = NULL; 475 476 crit_enter(); 477 if (volume->io.lock.refs == 1) { 478 ++volume->io.loading; 479 hammer_lock_ex(&volume->io.lock); 480 if (volume->io.lock.refs == 1) { 481 volume->ondisk = NULL; 482 bp = hammer_io_release(&volume->io, flush); 483 } 484 --volume->io.loading; 485 hammer_unlock(&volume->io.lock); 486 } 487 hammer_unref(&volume->io.lock); 488 if (bp) 489 brelse(bp); 490 crit_exit(); 491 } 492 493 int 494 hammer_mountcheck_volumes(struct hammer_mount *hmp) 495 { 496 hammer_volume_t vol; 497 int i; 498 499 for (i = 0; i < hmp->nvolumes; ++i) { 500 vol = RB_LOOKUP(hammer_vol_rb_tree, &hmp->rb_vols_root, i); 501 if (vol == NULL) 502 return(EINVAL); 503 } 504 return(0); 505 } 506 507 /************************************************************************ 508 * BUFFERS * 509 ************************************************************************ 510 * 511 * Manage buffers. Currently all blockmap-backed zones are direct-mapped 512 * to zone-2 buffer offsets, without a translation stage. However, the 513 * hammer_buffer structure is indexed by its zoneX_offset, not its 514 * zone2_offset. 515 * 516 * The proper zone must be maintained throughout the code-base all the way 517 * through to the big-block allocator, or routines like hammer_del_buffers() 518 * will not be able to locate all potentially conflicting buffers. 519 */ 520 hammer_buffer_t 521 hammer_get_buffer(hammer_mount_t hmp, hammer_off_t buf_offset, 522 int bytes, int isnew, int *errorp) 523 { 524 hammer_buffer_t buffer; 525 hammer_volume_t volume; 526 hammer_off_t zone2_offset; 527 hammer_io_type_t iotype; 528 int vol_no; 529 int zone; 530 531 buf_offset &= ~HAMMER_BUFMASK64; 532 again: 533 /* 534 * Shortcut if the buffer is already cached 535 */ 536 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, buf_offset); 537 if (buffer) { 538 if (buffer->io.lock.refs == 0) 539 ++hammer_count_refedbufs; 540 hammer_ref(&buffer->io.lock); 541 542 /* 543 * Once refed the ondisk field will not be cleared by 544 * any other action. 545 */ 546 if (buffer->ondisk && buffer->io.loading == 0) { 547 *errorp = 0; 548 return(buffer); 549 } 550 551 /* 552 * The buffer is no longer loose if it has a ref, and 553 * cannot become loose once it gains a ref. Loose 554 * buffers will never be in a modified state. This should 555 * only occur on the 0->1 transition of refs. 556 * 557 * lose_list can be modified via a biodone() interrupt. 558 */ 559 if (buffer->io.mod_list == &hmp->lose_list) { 560 crit_enter(); /* biodone race against list */ 561 TAILQ_REMOVE(buffer->io.mod_list, &buffer->io, 562 mod_entry); 563 crit_exit(); 564 buffer->io.mod_list = NULL; 565 KKASSERT(buffer->io.modified == 0); 566 } 567 goto found; 568 } 569 570 /* 571 * What is the buffer class? 572 */ 573 zone = HAMMER_ZONE_DECODE(buf_offset); 574 575 switch(zone) { 576 case HAMMER_ZONE_LARGE_DATA_INDEX: 577 case HAMMER_ZONE_SMALL_DATA_INDEX: 578 iotype = HAMMER_STRUCTURE_DATA_BUFFER; 579 break; 580 case HAMMER_ZONE_UNDO_INDEX: 581 iotype = HAMMER_STRUCTURE_UNDO_BUFFER; 582 break; 583 case HAMMER_ZONE_META_INDEX: 584 default: 585 /* 586 * NOTE: inode data and directory entries are placed in this 587 * zone. inode atime/mtime is updated in-place and thus 588 * buffers containing inodes must be synchronized as 589 * meta-buffers, same as buffers containing B-Tree info. 590 */ 591 iotype = HAMMER_STRUCTURE_META_BUFFER; 592 break; 593 } 594 595 /* 596 * Handle blockmap offset translations 597 */ 598 if (zone >= HAMMER_ZONE_BTREE_INDEX) { 599 zone2_offset = hammer_blockmap_lookup(hmp, buf_offset, errorp); 600 } else if (zone == HAMMER_ZONE_UNDO_INDEX) { 601 zone2_offset = hammer_undo_lookup(hmp, buf_offset, errorp); 602 } else { 603 KKASSERT(zone == HAMMER_ZONE_RAW_BUFFER_INDEX); 604 zone2_offset = buf_offset; 605 *errorp = 0; 606 } 607 if (*errorp) 608 return(NULL); 609 610 /* 611 * NOTE: zone2_offset and maxbuf_off are both full zone-2 offset 612 * specifications. 613 */ 614 KKASSERT((zone2_offset & HAMMER_OFF_ZONE_MASK) == 615 HAMMER_ZONE_RAW_BUFFER); 616 vol_no = HAMMER_VOL_DECODE(zone2_offset); 617 volume = hammer_get_volume(hmp, vol_no, errorp); 618 if (volume == NULL) 619 return(NULL); 620 621 KKASSERT(zone2_offset < volume->maxbuf_off); 622 623 /* 624 * Allocate a new buffer structure. We will check for races later. 625 */ 626 ++hammer_count_buffers; 627 buffer = kmalloc(sizeof(*buffer), hmp->m_misc, 628 M_WAITOK|M_ZERO|M_USE_RESERVE); 629 buffer->zone2_offset = zone2_offset; 630 buffer->zoneX_offset = buf_offset; 631 632 hammer_io_init(&buffer->io, volume, iotype); 633 buffer->io.offset = volume->ondisk->vol_buf_beg + 634 (zone2_offset & HAMMER_OFF_SHORT_MASK); 635 buffer->io.bytes = bytes; 636 TAILQ_INIT(&buffer->clist); 637 hammer_ref(&buffer->io.lock); 638 639 /* 640 * Insert the buffer into the RB tree and handle late collisions. 641 */ 642 if (RB_INSERT(hammer_buf_rb_tree, &hmp->rb_bufs_root, buffer)) { 643 hammer_unref(&buffer->io.lock); /* safety */ 644 --hammer_count_buffers; 645 hammer_rel_volume(volume, 0); 646 buffer->io.volume = NULL; /* safety */ 647 kfree(buffer, hmp->m_misc); 648 goto again; 649 } 650 ++hammer_count_refedbufs; 651 found: 652 653 /* 654 * Deal with on-disk info and loading races. 655 */ 656 if (buffer->ondisk == NULL || buffer->io.loading) { 657 *errorp = hammer_load_buffer(buffer, isnew); 658 if (*errorp) { 659 hammer_rel_buffer(buffer, 1); 660 buffer = NULL; 661 } 662 } else { 663 *errorp = 0; 664 } 665 return(buffer); 666 } 667 668 /* 669 * This is used by the direct-read code to deal with large-data buffers 670 * created by the reblocker and mirror-write code. The direct-read code 671 * bypasses the HAMMER buffer subsystem and so any aliased dirty or write- 672 * running hammer buffers must be fully synced to disk before we can issue 673 * the direct-read. 674 * 675 * This code path is not considered critical as only the rebocker and 676 * mirror-write code will create large-data buffers via the HAMMER buffer 677 * subsystem. They do that because they operate at the B-Tree level and 678 * do not access the vnode/inode structures. 679 */ 680 void 681 hammer_sync_buffers(hammer_mount_t hmp, hammer_off_t base_offset, int bytes) 682 { 683 hammer_buffer_t buffer; 684 int error; 685 686 KKASSERT((base_offset & HAMMER_OFF_ZONE_MASK) == 687 HAMMER_ZONE_LARGE_DATA); 688 689 while (bytes > 0) { 690 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 691 base_offset); 692 if (buffer && (buffer->io.modified || buffer->io.running)) { 693 error = hammer_ref_buffer(buffer); 694 if (error == 0) { 695 hammer_io_wait(&buffer->io); 696 if (buffer->io.modified) { 697 hammer_io_write_interlock(&buffer->io); 698 hammer_io_flush(&buffer->io); 699 hammer_io_done_interlock(&buffer->io); 700 hammer_io_wait(&buffer->io); 701 } 702 hammer_rel_buffer(buffer, 0); 703 } 704 } 705 base_offset += HAMMER_BUFSIZE; 706 bytes -= HAMMER_BUFSIZE; 707 } 708 } 709 710 /* 711 * Destroy all buffers covering the specified zoneX offset range. This 712 * is called when the related blockmap layer2 entry is freed or when 713 * a direct write bypasses our buffer/buffer-cache subsystem. 714 * 715 * The buffers may be referenced by the caller itself. Setting reclaim 716 * will cause the buffer to be destroyed when it's ref count reaches zero. 717 * 718 * Return 0 on success, EAGAIN if some buffers could not be destroyed due 719 * to additional references held by other threads, or some other (typically 720 * fatal) error. 721 */ 722 int 723 hammer_del_buffers(hammer_mount_t hmp, hammer_off_t base_offset, 724 hammer_off_t zone2_offset, int bytes, 725 int report_conflicts) 726 { 727 hammer_buffer_t buffer; 728 hammer_volume_t volume; 729 int vol_no; 730 int error; 731 int ret_error; 732 733 vol_no = HAMMER_VOL_DECODE(zone2_offset); 734 volume = hammer_get_volume(hmp, vol_no, &ret_error); 735 KKASSERT(ret_error == 0); 736 737 while (bytes > 0) { 738 buffer = RB_LOOKUP(hammer_buf_rb_tree, &hmp->rb_bufs_root, 739 base_offset); 740 if (buffer) { 741 error = hammer_ref_buffer(buffer); 742 if (error == 0 && buffer->io.lock.refs != 1) { 743 error = EAGAIN; 744 hammer_rel_buffer(buffer, 0); 745 } 746 if (error == 0) { 747 KKASSERT(buffer->zone2_offset == zone2_offset); 748 hammer_io_clear_modify(&buffer->io, 1); 749 buffer->io.reclaim = 1; 750 buffer->io.waitdep = 1; 751 KKASSERT(buffer->io.volume == volume); 752 hammer_rel_buffer(buffer, 0); 753 } 754 } else { 755 error = hammer_io_inval(volume, zone2_offset); 756 } 757 if (error) { 758 ret_error = error; 759 if (report_conflicts || 760 (hammer_debug_general & 0x8000)) { 761 kprintf("hammer_del_buffers: unable to " 762 "invalidate %016llx buffer=%p rep=%d\n", 763 (long long)base_offset, 764 buffer, report_conflicts); 765 } 766 } 767 base_offset += HAMMER_BUFSIZE; 768 zone2_offset += HAMMER_BUFSIZE; 769 bytes -= HAMMER_BUFSIZE; 770 } 771 hammer_rel_volume(volume, 0); 772 return (ret_error); 773 } 774 775 static int 776 hammer_load_buffer(hammer_buffer_t buffer, int isnew) 777 { 778 hammer_volume_t volume; 779 int error; 780 781 /* 782 * Load the buffer's on-disk info 783 */ 784 volume = buffer->io.volume; 785 ++buffer->io.loading; 786 hammer_lock_ex(&buffer->io.lock); 787 788 if (hammer_debug_io & 0x0001) { 789 kprintf("load_buffer %016llx %016llx isnew=%d od=%p\n", 790 (long long)buffer->zoneX_offset, 791 (long long)buffer->zone2_offset, 792 isnew, buffer->ondisk); 793 } 794 795 if (buffer->ondisk == NULL) { 796 if (isnew) { 797 error = hammer_io_new(volume->devvp, &buffer->io); 798 } else { 799 error = hammer_io_read(volume->devvp, &buffer->io, 800 volume->maxraw_off); 801 } 802 if (error == 0) 803 buffer->ondisk = (void *)buffer->io.bp->b_data; 804 } else if (isnew) { 805 error = hammer_io_new(volume->devvp, &buffer->io); 806 } else { 807 error = 0; 808 } 809 --buffer->io.loading; 810 hammer_unlock(&buffer->io.lock); 811 return (error); 812 } 813 814 /* 815 * NOTE: Called from RB_SCAN, must return >= 0 for scan to continue. 816 * This routine is only called during unmount. 817 */ 818 int 819 hammer_unload_buffer(hammer_buffer_t buffer, void *data __unused) 820 { 821 /* 822 * Clean up the persistent ref ioerror might have on the buffer 823 * and acquire a ref (steal ioerror's if we can). 824 */ 825 if (buffer->io.ioerror) { 826 buffer->io.ioerror = 0; 827 } else { 828 if (buffer->io.lock.refs == 0) 829 ++hammer_count_refedbufs; 830 hammer_ref(&buffer->io.lock); 831 } 832 833 /* 834 * We must not flush a dirty buffer to disk on umount. It should 835 * have already been dealt with by the flusher, or we may be in 836 * catastrophic failure. 837 * 838 * We must set waitdep to ensure that a running buffer is waited 839 * on and released prior to us trying to unload the volume. 840 */ 841 hammer_io_clear_modify(&buffer->io, 1); 842 hammer_flush_buffer_nodes(buffer); 843 KKASSERT(buffer->io.lock.refs == 1); 844 buffer->io.waitdep = 1; 845 hammer_rel_buffer(buffer, 2); 846 return(0); 847 } 848 849 /* 850 * Reference a buffer that is either already referenced or via a specially 851 * handled pointer (aka cursor->buffer). 852 */ 853 int 854 hammer_ref_buffer(hammer_buffer_t buffer) 855 { 856 int error; 857 858 if (buffer->io.lock.refs == 0) 859 ++hammer_count_refedbufs; 860 hammer_ref(&buffer->io.lock); 861 862 /* 863 * At this point a biodone() will not touch the buffer other then 864 * incidental bits. However, lose_list can be modified via 865 * a biodone() interrupt. 866 * 867 * No longer loose 868 */ 869 if (buffer->io.mod_list == &buffer->io.hmp->lose_list) { 870 crit_enter(); 871 TAILQ_REMOVE(buffer->io.mod_list, &buffer->io, mod_entry); 872 buffer->io.mod_list = NULL; 873 crit_exit(); 874 } 875 876 if (buffer->ondisk == NULL || buffer->io.loading) { 877 error = hammer_load_buffer(buffer, 0); 878 if (error) { 879 hammer_rel_buffer(buffer, 1); 880 /* 881 * NOTE: buffer pointer can become stale after 882 * the above release. 883 */ 884 } 885 } else { 886 error = 0; 887 } 888 return(error); 889 } 890 891 /* 892 * Release a buffer. We have to deal with several places where 893 * another thread can ref the buffer. 894 * 895 * Only destroy the structure itself if the related buffer cache buffer 896 * was disassociated from it. This ties the management of the structure 897 * to the buffer cache subsystem. buffer->ondisk determines whether the 898 * embedded io is referenced or not. 899 */ 900 void 901 hammer_rel_buffer(hammer_buffer_t buffer, int flush) 902 { 903 hammer_volume_t volume; 904 hammer_mount_t hmp; 905 struct buf *bp = NULL; 906 int freeme = 0; 907 908 hmp = buffer->io.hmp; 909 910 crit_enter(); 911 if (buffer->io.lock.refs == 1) { 912 ++buffer->io.loading; /* force interlock check */ 913 hammer_lock_ex(&buffer->io.lock); 914 if (buffer->io.lock.refs == 1) { 915 bp = hammer_io_release(&buffer->io, flush); 916 917 if (buffer->io.lock.refs == 1) 918 --hammer_count_refedbufs; 919 920 if (buffer->io.bp == NULL && 921 buffer->io.lock.refs == 1) { 922 /* 923 * Final cleanup 924 * 925 * NOTE: It is impossible for any associated 926 * B-Tree nodes to have refs if the buffer 927 * has no additional refs. 928 */ 929 RB_REMOVE(hammer_buf_rb_tree, 930 &buffer->io.hmp->rb_bufs_root, 931 buffer); 932 volume = buffer->io.volume; 933 buffer->io.volume = NULL; /* sanity */ 934 hammer_rel_volume(volume, 0); 935 hammer_io_clear_modlist(&buffer->io); 936 hammer_flush_buffer_nodes(buffer); 937 KKASSERT(TAILQ_EMPTY(&buffer->clist)); 938 freeme = 1; 939 } 940 } 941 --buffer->io.loading; 942 hammer_unlock(&buffer->io.lock); 943 } 944 hammer_unref(&buffer->io.lock); 945 crit_exit(); 946 if (bp) 947 brelse(bp); 948 if (freeme) { 949 --hammer_count_buffers; 950 kfree(buffer, hmp->m_misc); 951 } 952 } 953 954 /* 955 * Access the filesystem buffer containing the specified hammer offset. 956 * buf_offset is a conglomeration of the volume number and vol_buf_beg 957 * relative buffer offset. It must also have bit 55 set to be valid. 958 * (see hammer_off_t in hammer_disk.h). 959 * 960 * Any prior buffer in *bufferp will be released and replaced by the 961 * requested buffer. 962 * 963 * NOTE: The buffer is indexed via its zoneX_offset but we allow the 964 * passed cached *bufferp to match against either zoneX or zone2. 965 */ 966 static __inline 967 void * 968 _hammer_bread(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 969 int *errorp, struct hammer_buffer **bufferp) 970 { 971 hammer_buffer_t buffer; 972 int32_t xoff = (int32_t)buf_offset & HAMMER_BUFMASK; 973 974 buf_offset &= ~HAMMER_BUFMASK64; 975 KKASSERT((buf_offset & HAMMER_OFF_ZONE_MASK) != 0); 976 977 buffer = *bufferp; 978 if (buffer == NULL || (buffer->zone2_offset != buf_offset && 979 buffer->zoneX_offset != buf_offset)) { 980 if (buffer) 981 hammer_rel_buffer(buffer, 0); 982 buffer = hammer_get_buffer(hmp, buf_offset, bytes, 0, errorp); 983 *bufferp = buffer; 984 } else { 985 *errorp = 0; 986 } 987 988 /* 989 * Return a pointer to the buffer data. 990 */ 991 if (buffer == NULL) 992 return(NULL); 993 else 994 return((char *)buffer->ondisk + xoff); 995 } 996 997 void * 998 hammer_bread(hammer_mount_t hmp, hammer_off_t buf_offset, 999 int *errorp, struct hammer_buffer **bufferp) 1000 { 1001 return(_hammer_bread(hmp, buf_offset, HAMMER_BUFSIZE, errorp, bufferp)); 1002 } 1003 1004 void * 1005 hammer_bread_ext(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1006 int *errorp, struct hammer_buffer **bufferp) 1007 { 1008 bytes = (bytes + HAMMER_BUFMASK) & ~HAMMER_BUFMASK; 1009 return(_hammer_bread(hmp, buf_offset, bytes, errorp, bufferp)); 1010 } 1011 1012 /* 1013 * Access the filesystem buffer containing the specified hammer offset. 1014 * No disk read operation occurs. The result buffer may contain garbage. 1015 * 1016 * Any prior buffer in *bufferp will be released and replaced by the 1017 * requested buffer. 1018 * 1019 * This function marks the buffer dirty but does not increment its 1020 * modify_refs count. 1021 */ 1022 static __inline 1023 void * 1024 _hammer_bnew(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1025 int *errorp, struct hammer_buffer **bufferp) 1026 { 1027 hammer_buffer_t buffer; 1028 int32_t xoff = (int32_t)buf_offset & HAMMER_BUFMASK; 1029 1030 buf_offset &= ~HAMMER_BUFMASK64; 1031 1032 buffer = *bufferp; 1033 if (buffer == NULL || (buffer->zone2_offset != buf_offset && 1034 buffer->zoneX_offset != buf_offset)) { 1035 if (buffer) 1036 hammer_rel_buffer(buffer, 0); 1037 buffer = hammer_get_buffer(hmp, buf_offset, bytes, 1, errorp); 1038 *bufferp = buffer; 1039 } else { 1040 *errorp = 0; 1041 } 1042 1043 /* 1044 * Return a pointer to the buffer data. 1045 */ 1046 if (buffer == NULL) 1047 return(NULL); 1048 else 1049 return((char *)buffer->ondisk + xoff); 1050 } 1051 1052 void * 1053 hammer_bnew(hammer_mount_t hmp, hammer_off_t buf_offset, 1054 int *errorp, struct hammer_buffer **bufferp) 1055 { 1056 return(_hammer_bnew(hmp, buf_offset, HAMMER_BUFSIZE, errorp, bufferp)); 1057 } 1058 1059 void * 1060 hammer_bnew_ext(hammer_mount_t hmp, hammer_off_t buf_offset, int bytes, 1061 int *errorp, struct hammer_buffer **bufferp) 1062 { 1063 bytes = (bytes + HAMMER_BUFMASK) & ~HAMMER_BUFMASK; 1064 return(_hammer_bnew(hmp, buf_offset, bytes, errorp, bufferp)); 1065 } 1066 1067 /************************************************************************ 1068 * NODES * 1069 ************************************************************************ 1070 * 1071 * Manage B-Tree nodes. B-Tree nodes represent the primary indexing 1072 * method used by the HAMMER filesystem. 1073 * 1074 * Unlike other HAMMER structures, a hammer_node can be PASSIVELY 1075 * associated with its buffer, and will only referenced the buffer while 1076 * the node itself is referenced. 1077 * 1078 * A hammer_node can also be passively associated with other HAMMER 1079 * structures, such as inodes, while retaining 0 references. These 1080 * associations can be cleared backwards using a pointer-to-pointer in 1081 * the hammer_node. 1082 * 1083 * This allows the HAMMER implementation to cache hammer_nodes long-term 1084 * and short-cut a great deal of the infrastructure's complexity. In 1085 * most cases a cached node can be reacquired without having to dip into 1086 * either the buffer or cluster management code. 1087 * 1088 * The caller must pass a referenced cluster on call and will retain 1089 * ownership of the reference on return. The node will acquire its own 1090 * additional references, if necessary. 1091 */ 1092 hammer_node_t 1093 hammer_get_node(hammer_transaction_t trans, hammer_off_t node_offset, 1094 int isnew, int *errorp) 1095 { 1096 hammer_mount_t hmp = trans->hmp; 1097 hammer_node_t node; 1098 1099 KKASSERT((node_offset & HAMMER_OFF_ZONE_MASK) == HAMMER_ZONE_BTREE); 1100 1101 /* 1102 * Locate the structure, allocating one if necessary. 1103 */ 1104 again: 1105 node = RB_LOOKUP(hammer_nod_rb_tree, &hmp->rb_nods_root, node_offset); 1106 if (node == NULL) { 1107 ++hammer_count_nodes; 1108 node = kmalloc(sizeof(*node), hmp->m_misc, M_WAITOK|M_ZERO|M_USE_RESERVE); 1109 node->node_offset = node_offset; 1110 node->hmp = hmp; 1111 TAILQ_INIT(&node->cursor_list); 1112 TAILQ_INIT(&node->cache_list); 1113 if (RB_INSERT(hammer_nod_rb_tree, &hmp->rb_nods_root, node)) { 1114 --hammer_count_nodes; 1115 kfree(node, hmp->m_misc); 1116 goto again; 1117 } 1118 } 1119 hammer_ref(&node->lock); 1120 if (node->ondisk) { 1121 *errorp = 0; 1122 } else { 1123 *errorp = hammer_load_node(trans, node, isnew); 1124 trans->flags |= HAMMER_TRANSF_DIDIO; 1125 } 1126 if (*errorp) { 1127 hammer_rel_node(node); 1128 node = NULL; 1129 } 1130 return(node); 1131 } 1132 1133 /* 1134 * Reference an already-referenced node. 1135 */ 1136 void 1137 hammer_ref_node(hammer_node_t node) 1138 { 1139 KKASSERT(node->lock.refs > 0 && node->ondisk != NULL); 1140 hammer_ref(&node->lock); 1141 } 1142 1143 /* 1144 * Load a node's on-disk data reference. 1145 */ 1146 static int 1147 hammer_load_node(hammer_transaction_t trans, hammer_node_t node, int isnew) 1148 { 1149 hammer_buffer_t buffer; 1150 hammer_off_t buf_offset; 1151 int error; 1152 1153 error = 0; 1154 ++node->loading; 1155 hammer_lock_ex(&node->lock); 1156 if (node->ondisk == NULL) { 1157 /* 1158 * This is a little confusing but the jist is that 1159 * node->buffer determines whether the node is on 1160 * the buffer's clist and node->ondisk determines 1161 * whether the buffer is referenced. 1162 * 1163 * We could be racing a buffer release, in which case 1164 * node->buffer may become NULL while we are blocked 1165 * referencing the buffer. 1166 */ 1167 if ((buffer = node->buffer) != NULL) { 1168 error = hammer_ref_buffer(buffer); 1169 if (error == 0 && node->buffer == NULL) { 1170 TAILQ_INSERT_TAIL(&buffer->clist, 1171 node, entry); 1172 node->buffer = buffer; 1173 } 1174 } else { 1175 buf_offset = node->node_offset & ~HAMMER_BUFMASK64; 1176 buffer = hammer_get_buffer(node->hmp, buf_offset, 1177 HAMMER_BUFSIZE, 0, &error); 1178 if (buffer) { 1179 KKASSERT(error == 0); 1180 TAILQ_INSERT_TAIL(&buffer->clist, 1181 node, entry); 1182 node->buffer = buffer; 1183 } 1184 } 1185 if (error) 1186 goto failed; 1187 node->ondisk = (void *)((char *)buffer->ondisk + 1188 (node->node_offset & HAMMER_BUFMASK)); 1189 1190 /* 1191 * Check CRC. NOTE: Neither flag is set and the CRC is not 1192 * generated on new B-Tree nodes. 1193 */ 1194 if (isnew == 0 && 1195 (node->flags & HAMMER_NODE_CRCANY) == 0) { 1196 if (hammer_crc_test_btree(node->ondisk) == 0) { 1197 if (hammer_debug_debug & 0x0002) 1198 Debugger("CRC FAILED: B-TREE NODE"); 1199 node->flags |= HAMMER_NODE_CRCBAD; 1200 } else { 1201 node->flags |= HAMMER_NODE_CRCGOOD; 1202 } 1203 } 1204 } 1205 if (node->flags & HAMMER_NODE_CRCBAD) { 1206 if (trans->flags & HAMMER_TRANSF_CRCDOM) 1207 error = EDOM; 1208 else 1209 error = EIO; 1210 } 1211 failed: 1212 --node->loading; 1213 hammer_unlock(&node->lock); 1214 return (error); 1215 } 1216 1217 /* 1218 * Safely reference a node, interlock against flushes via the IO subsystem. 1219 */ 1220 hammer_node_t 1221 hammer_ref_node_safe(hammer_transaction_t trans, hammer_node_cache_t cache, 1222 int *errorp) 1223 { 1224 hammer_node_t node; 1225 1226 node = cache->node; 1227 if (node != NULL) { 1228 hammer_ref(&node->lock); 1229 if (node->ondisk) { 1230 if (node->flags & HAMMER_NODE_CRCBAD) { 1231 if (trans->flags & HAMMER_TRANSF_CRCDOM) 1232 *errorp = EDOM; 1233 else 1234 *errorp = EIO; 1235 } else { 1236 *errorp = 0; 1237 } 1238 } else { 1239 *errorp = hammer_load_node(trans, node, 0); 1240 } 1241 if (*errorp) { 1242 hammer_rel_node(node); 1243 node = NULL; 1244 } 1245 } else { 1246 *errorp = ENOENT; 1247 } 1248 return(node); 1249 } 1250 1251 /* 1252 * Release a hammer_node. On the last release the node dereferences 1253 * its underlying buffer and may or may not be destroyed. 1254 */ 1255 void 1256 hammer_rel_node(hammer_node_t node) 1257 { 1258 hammer_buffer_t buffer; 1259 1260 /* 1261 * If this isn't the last ref just decrement the ref count and 1262 * return. 1263 */ 1264 if (node->lock.refs > 1) { 1265 hammer_unref(&node->lock); 1266 return; 1267 } 1268 1269 /* 1270 * If there is no ondisk info or no buffer the node failed to load, 1271 * remove the last reference and destroy the node. 1272 */ 1273 if (node->ondisk == NULL) { 1274 hammer_unref(&node->lock); 1275 hammer_flush_node(node); 1276 /* node is stale now */ 1277 return; 1278 } 1279 1280 /* 1281 * Do not disassociate the node from the buffer if it represents 1282 * a modified B-Tree node that still needs its crc to be generated. 1283 */ 1284 if (node->flags & HAMMER_NODE_NEEDSCRC) 1285 return; 1286 1287 /* 1288 * Do final cleanups and then either destroy the node and leave it 1289 * passively cached. The buffer reference is removed regardless. 1290 */ 1291 buffer = node->buffer; 1292 node->ondisk = NULL; 1293 1294 if ((node->flags & HAMMER_NODE_FLUSH) == 0) { 1295 hammer_unref(&node->lock); 1296 hammer_rel_buffer(buffer, 0); 1297 return; 1298 } 1299 1300 /* 1301 * Destroy the node. 1302 */ 1303 hammer_unref(&node->lock); 1304 hammer_flush_node(node); 1305 /* node is stale */ 1306 hammer_rel_buffer(buffer, 0); 1307 } 1308 1309 /* 1310 * Free space on-media associated with a B-Tree node. 1311 */ 1312 void 1313 hammer_delete_node(hammer_transaction_t trans, hammer_node_t node) 1314 { 1315 KKASSERT((node->flags & HAMMER_NODE_DELETED) == 0); 1316 node->flags |= HAMMER_NODE_DELETED; 1317 hammer_blockmap_free(trans, node->node_offset, sizeof(*node->ondisk)); 1318 } 1319 1320 /* 1321 * Passively cache a referenced hammer_node. The caller may release 1322 * the node on return. 1323 */ 1324 void 1325 hammer_cache_node(hammer_node_cache_t cache, hammer_node_t node) 1326 { 1327 /* 1328 * If the node doesn't exist, or is being deleted, don't cache it! 1329 * 1330 * The node can only ever be NULL in the I/O failure path. 1331 */ 1332 if (node == NULL || (node->flags & HAMMER_NODE_DELETED)) 1333 return; 1334 if (cache->node == node) 1335 return; 1336 while (cache->node) 1337 hammer_uncache_node(cache); 1338 if (node->flags & HAMMER_NODE_DELETED) 1339 return; 1340 cache->node = node; 1341 TAILQ_INSERT_TAIL(&node->cache_list, cache, entry); 1342 } 1343 1344 void 1345 hammer_uncache_node(hammer_node_cache_t cache) 1346 { 1347 hammer_node_t node; 1348 1349 if ((node = cache->node) != NULL) { 1350 TAILQ_REMOVE(&node->cache_list, cache, entry); 1351 cache->node = NULL; 1352 if (TAILQ_EMPTY(&node->cache_list)) 1353 hammer_flush_node(node); 1354 } 1355 } 1356 1357 /* 1358 * Remove a node's cache references and destroy the node if it has no 1359 * other references or backing store. 1360 */ 1361 void 1362 hammer_flush_node(hammer_node_t node) 1363 { 1364 hammer_node_cache_t cache; 1365 hammer_buffer_t buffer; 1366 hammer_mount_t hmp = node->hmp; 1367 1368 while ((cache = TAILQ_FIRST(&node->cache_list)) != NULL) { 1369 TAILQ_REMOVE(&node->cache_list, cache, entry); 1370 cache->node = NULL; 1371 } 1372 if (node->lock.refs == 0 && node->ondisk == NULL) { 1373 KKASSERT((node->flags & HAMMER_NODE_NEEDSCRC) == 0); 1374 RB_REMOVE(hammer_nod_rb_tree, &node->hmp->rb_nods_root, node); 1375 if ((buffer = node->buffer) != NULL) { 1376 node->buffer = NULL; 1377 TAILQ_REMOVE(&buffer->clist, node, entry); 1378 /* buffer is unreferenced because ondisk is NULL */ 1379 } 1380 --hammer_count_nodes; 1381 kfree(node, hmp->m_misc); 1382 } 1383 } 1384 1385 /* 1386 * Flush passively cached B-Tree nodes associated with this buffer. 1387 * This is only called when the buffer is about to be destroyed, so 1388 * none of the nodes should have any references. The buffer is locked. 1389 * 1390 * We may be interlocked with the buffer. 1391 */ 1392 void 1393 hammer_flush_buffer_nodes(hammer_buffer_t buffer) 1394 { 1395 hammer_node_t node; 1396 1397 while ((node = TAILQ_FIRST(&buffer->clist)) != NULL) { 1398 KKASSERT(node->ondisk == NULL); 1399 KKASSERT((node->flags & HAMMER_NODE_NEEDSCRC) == 0); 1400 1401 if (node->lock.refs == 0) { 1402 hammer_ref(&node->lock); 1403 node->flags |= HAMMER_NODE_FLUSH; 1404 hammer_rel_node(node); 1405 } else { 1406 KKASSERT(node->loading != 0); 1407 KKASSERT(node->buffer != NULL); 1408 buffer = node->buffer; 1409 node->buffer = NULL; 1410 TAILQ_REMOVE(&buffer->clist, node, entry); 1411 /* buffer is unreferenced because ondisk is NULL */ 1412 } 1413 } 1414 } 1415 1416 1417 /************************************************************************ 1418 * ALLOCATORS * 1419 ************************************************************************/ 1420 1421 /* 1422 * Allocate a B-Tree node. 1423 */ 1424 hammer_node_t 1425 hammer_alloc_btree(hammer_transaction_t trans, hammer_off_t hint, int *errorp) 1426 { 1427 hammer_buffer_t buffer = NULL; 1428 hammer_node_t node = NULL; 1429 hammer_off_t node_offset; 1430 1431 node_offset = hammer_blockmap_alloc(trans, HAMMER_ZONE_BTREE_INDEX, 1432 sizeof(struct hammer_node_ondisk), 1433 hint, errorp); 1434 if (*errorp == 0) { 1435 node = hammer_get_node(trans, node_offset, 1, errorp); 1436 hammer_modify_node_noundo(trans, node); 1437 bzero(node->ondisk, sizeof(*node->ondisk)); 1438 hammer_modify_node_done(node); 1439 } 1440 if (buffer) 1441 hammer_rel_buffer(buffer, 0); 1442 return(node); 1443 } 1444 1445 /* 1446 * Allocate data. If the address of a data buffer is supplied then 1447 * any prior non-NULL *data_bufferp will be released and *data_bufferp 1448 * will be set to the related buffer. The caller must release it when 1449 * finally done. The initial *data_bufferp should be set to NULL by 1450 * the caller. 1451 * 1452 * The caller is responsible for making hammer_modify*() calls on the 1453 * *data_bufferp. 1454 */ 1455 void * 1456 hammer_alloc_data(hammer_transaction_t trans, int32_t data_len, 1457 u_int16_t rec_type, hammer_off_t *data_offsetp, 1458 struct hammer_buffer **data_bufferp, 1459 hammer_off_t hint, int *errorp) 1460 { 1461 void *data; 1462 int zone; 1463 1464 /* 1465 * Allocate data 1466 */ 1467 if (data_len) { 1468 switch(rec_type) { 1469 case HAMMER_RECTYPE_INODE: 1470 case HAMMER_RECTYPE_DIRENTRY: 1471 case HAMMER_RECTYPE_EXT: 1472 case HAMMER_RECTYPE_FIX: 1473 case HAMMER_RECTYPE_PFS: 1474 zone = HAMMER_ZONE_META_INDEX; 1475 break; 1476 case HAMMER_RECTYPE_DATA: 1477 case HAMMER_RECTYPE_DB: 1478 if (data_len <= HAMMER_BUFSIZE / 2) { 1479 zone = HAMMER_ZONE_SMALL_DATA_INDEX; 1480 } else { 1481 data_len = (data_len + HAMMER_BUFMASK) & 1482 ~HAMMER_BUFMASK; 1483 zone = HAMMER_ZONE_LARGE_DATA_INDEX; 1484 } 1485 break; 1486 default: 1487 panic("hammer_alloc_data: rec_type %04x unknown", 1488 rec_type); 1489 zone = 0; /* NOT REACHED */ 1490 break; 1491 } 1492 *data_offsetp = hammer_blockmap_alloc(trans, zone, data_len, 1493 hint, errorp); 1494 } else { 1495 *data_offsetp = 0; 1496 } 1497 if (*errorp == 0 && data_bufferp) { 1498 if (data_len) { 1499 data = hammer_bread_ext(trans->hmp, *data_offsetp, 1500 data_len, errorp, data_bufferp); 1501 } else { 1502 data = NULL; 1503 } 1504 } else { 1505 data = NULL; 1506 } 1507 return(data); 1508 } 1509 1510 /* 1511 * Sync dirty buffers to the media and clean-up any loose ends. 1512 * 1513 * These functions do not start the flusher going, they simply 1514 * queue everything up to the flusher. 1515 */ 1516 static int hammer_sync_scan1(struct mount *mp, struct vnode *vp, void *data); 1517 static int hammer_sync_scan2(struct mount *mp, struct vnode *vp, void *data); 1518 1519 int 1520 hammer_queue_inodes_flusher(hammer_mount_t hmp, int waitfor) 1521 { 1522 struct hammer_sync_info info; 1523 1524 info.error = 0; 1525 info.waitfor = waitfor; 1526 if (waitfor == MNT_WAIT) { 1527 vmntvnodescan(hmp->mp, VMSC_GETVP|VMSC_ONEPASS, 1528 hammer_sync_scan1, hammer_sync_scan2, &info); 1529 } else { 1530 vmntvnodescan(hmp->mp, VMSC_GETVP|VMSC_ONEPASS|VMSC_NOWAIT, 1531 hammer_sync_scan1, hammer_sync_scan2, &info); 1532 } 1533 return(info.error); 1534 } 1535 1536 /* 1537 * Filesystem sync. If doing a synchronous sync make a second pass on 1538 * the vnodes in case any were already flushing during the first pass, 1539 * and activate the flusher twice (the second time brings the UNDO FIFO's 1540 * start position up to the end position after the first call). 1541 */ 1542 int 1543 hammer_sync_hmp(hammer_mount_t hmp, int waitfor) 1544 { 1545 struct hammer_sync_info info; 1546 1547 info.error = 0; 1548 info.waitfor = MNT_NOWAIT; 1549 vmntvnodescan(hmp->mp, VMSC_GETVP|VMSC_NOWAIT, 1550 hammer_sync_scan1, hammer_sync_scan2, &info); 1551 if (info.error == 0 && waitfor == MNT_WAIT) { 1552 info.waitfor = waitfor; 1553 vmntvnodescan(hmp->mp, VMSC_GETVP, 1554 hammer_sync_scan1, hammer_sync_scan2, &info); 1555 } 1556 if (waitfor == MNT_WAIT) { 1557 hammer_flusher_sync(hmp); 1558 hammer_flusher_sync(hmp); 1559 } else { 1560 hammer_flusher_async(hmp, NULL); 1561 hammer_flusher_async(hmp, NULL); 1562 } 1563 return(info.error); 1564 } 1565 1566 static int 1567 hammer_sync_scan1(struct mount *mp, struct vnode *vp, void *data) 1568 { 1569 struct hammer_inode *ip; 1570 1571 ip = VTOI(vp); 1572 if (vp->v_type == VNON || ip == NULL || 1573 ((ip->flags & HAMMER_INODE_MODMASK) == 0 && 1574 RB_EMPTY(&vp->v_rbdirty_tree))) { 1575 return(-1); 1576 } 1577 return(0); 1578 } 1579 1580 static int 1581 hammer_sync_scan2(struct mount *mp, struct vnode *vp, void *data) 1582 { 1583 struct hammer_sync_info *info = data; 1584 struct hammer_inode *ip; 1585 int error; 1586 1587 ip = VTOI(vp); 1588 if (vp->v_type == VNON || vp->v_type == VBAD || 1589 ((ip->flags & HAMMER_INODE_MODMASK) == 0 && 1590 RB_EMPTY(&vp->v_rbdirty_tree))) { 1591 return(0); 1592 } 1593 error = VOP_FSYNC(vp, MNT_NOWAIT); 1594 if (error) 1595 info->error = error; 1596 return(0); 1597 } 1598 1599