1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2000-2005 Silicon Graphics, Inc. 4 * All Rights Reserved. 5 */ 6 #include "xfs.h" 7 #include "xfs_fs.h" 8 #include "xfs_shared.h" 9 #include "xfs_format.h" 10 #include "xfs_log_format.h" 11 #include "xfs_trans_resv.h" 12 #include "xfs_mount.h" 13 #include "xfs_errortag.h" 14 #include "xfs_error.h" 15 #include "xfs_trans.h" 16 #include "xfs_trans_priv.h" 17 #include "xfs_log.h" 18 #include "xfs_log_priv.h" 19 #include "xfs_log_recover.h" 20 #include "xfs_inode.h" 21 #include "xfs_trace.h" 22 #include "xfs_fsops.h" 23 #include "xfs_cksum.h" 24 #include "xfs_sysfs.h" 25 #include "xfs_sb.h" 26 #include "xfs_health.h" 27 28 kmem_zone_t *xfs_log_ticket_zone; 29 30 /* Local miscellaneous function prototypes */ 31 STATIC int 32 xlog_commit_record( 33 struct xlog *log, 34 struct xlog_ticket *ticket, 35 struct xlog_in_core **iclog, 36 xfs_lsn_t *commitlsnp); 37 38 STATIC struct xlog * 39 xlog_alloc_log( 40 struct xfs_mount *mp, 41 struct xfs_buftarg *log_target, 42 xfs_daddr_t blk_offset, 43 int num_bblks); 44 STATIC int 45 xlog_space_left( 46 struct xlog *log, 47 atomic64_t *head); 48 STATIC int 49 xlog_sync( 50 struct xlog *log, 51 struct xlog_in_core *iclog); 52 STATIC void 53 xlog_dealloc_log( 54 struct xlog *log); 55 56 /* local state machine functions */ 57 STATIC void xlog_state_done_syncing(xlog_in_core_t *iclog, int); 58 STATIC void 59 xlog_state_do_callback( 60 struct xlog *log, 61 int aborted, 62 struct xlog_in_core *iclog); 63 STATIC int 64 xlog_state_get_iclog_space( 65 struct xlog *log, 66 int len, 67 struct xlog_in_core **iclog, 68 struct xlog_ticket *ticket, 69 int *continued_write, 70 int *logoffsetp); 71 STATIC int 72 xlog_state_release_iclog( 73 struct xlog *log, 74 struct xlog_in_core *iclog); 75 STATIC void 76 xlog_state_switch_iclogs( 77 struct xlog *log, 78 struct xlog_in_core *iclog, 79 int eventual_size); 80 STATIC void 81 xlog_state_want_sync( 82 struct xlog *log, 83 struct xlog_in_core *iclog); 84 85 STATIC void 86 xlog_grant_push_ail( 87 struct xlog *log, 88 int need_bytes); 89 STATIC void 90 xlog_regrant_reserve_log_space( 91 struct xlog *log, 92 struct xlog_ticket *ticket); 93 STATIC void 94 xlog_ungrant_log_space( 95 struct xlog *log, 96 struct xlog_ticket *ticket); 97 98 #if defined(DEBUG) 99 STATIC void 100 xlog_verify_dest_ptr( 101 struct xlog *log, 102 void *ptr); 103 STATIC void 104 xlog_verify_grant_tail( 105 struct xlog *log); 106 STATIC void 107 xlog_verify_iclog( 108 struct xlog *log, 109 struct xlog_in_core *iclog, 110 int count, 111 bool syncing); 112 STATIC void 113 xlog_verify_tail_lsn( 114 struct xlog *log, 115 struct xlog_in_core *iclog, 116 xfs_lsn_t tail_lsn); 117 #else 118 #define xlog_verify_dest_ptr(a,b) 119 #define xlog_verify_grant_tail(a) 120 #define xlog_verify_iclog(a,b,c,d) 121 #define xlog_verify_tail_lsn(a,b,c) 122 #endif 123 124 STATIC int 125 xlog_iclogs_empty( 126 struct xlog *log); 127 128 static void 129 xlog_grant_sub_space( 130 struct xlog *log, 131 atomic64_t *head, 132 int bytes) 133 { 134 int64_t head_val = atomic64_read(head); 135 int64_t new, old; 136 137 do { 138 int cycle, space; 139 140 xlog_crack_grant_head_val(head_val, &cycle, &space); 141 142 space -= bytes; 143 if (space < 0) { 144 space += log->l_logsize; 145 cycle--; 146 } 147 148 old = head_val; 149 new = xlog_assign_grant_head_val(cycle, space); 150 head_val = atomic64_cmpxchg(head, old, new); 151 } while (head_val != old); 152 } 153 154 static void 155 xlog_grant_add_space( 156 struct xlog *log, 157 atomic64_t *head, 158 int bytes) 159 { 160 int64_t head_val = atomic64_read(head); 161 int64_t new, old; 162 163 do { 164 int tmp; 165 int cycle, space; 166 167 xlog_crack_grant_head_val(head_val, &cycle, &space); 168 169 tmp = log->l_logsize - space; 170 if (tmp > bytes) 171 space += bytes; 172 else { 173 space = bytes - tmp; 174 cycle++; 175 } 176 177 old = head_val; 178 new = xlog_assign_grant_head_val(cycle, space); 179 head_val = atomic64_cmpxchg(head, old, new); 180 } while (head_val != old); 181 } 182 183 STATIC void 184 xlog_grant_head_init( 185 struct xlog_grant_head *head) 186 { 187 xlog_assign_grant_head(&head->grant, 1, 0); 188 INIT_LIST_HEAD(&head->waiters); 189 spin_lock_init(&head->lock); 190 } 191 192 STATIC void 193 xlog_grant_head_wake_all( 194 struct xlog_grant_head *head) 195 { 196 struct xlog_ticket *tic; 197 198 spin_lock(&head->lock); 199 list_for_each_entry(tic, &head->waiters, t_queue) 200 wake_up_process(tic->t_task); 201 spin_unlock(&head->lock); 202 } 203 204 static inline int 205 xlog_ticket_reservation( 206 struct xlog *log, 207 struct xlog_grant_head *head, 208 struct xlog_ticket *tic) 209 { 210 if (head == &log->l_write_head) { 211 ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV); 212 return tic->t_unit_res; 213 } else { 214 if (tic->t_flags & XLOG_TIC_PERM_RESERV) 215 return tic->t_unit_res * tic->t_cnt; 216 else 217 return tic->t_unit_res; 218 } 219 } 220 221 STATIC bool 222 xlog_grant_head_wake( 223 struct xlog *log, 224 struct xlog_grant_head *head, 225 int *free_bytes) 226 { 227 struct xlog_ticket *tic; 228 int need_bytes; 229 230 list_for_each_entry(tic, &head->waiters, t_queue) { 231 need_bytes = xlog_ticket_reservation(log, head, tic); 232 if (*free_bytes < need_bytes) 233 return false; 234 235 *free_bytes -= need_bytes; 236 trace_xfs_log_grant_wake_up(log, tic); 237 wake_up_process(tic->t_task); 238 } 239 240 return true; 241 } 242 243 STATIC int 244 xlog_grant_head_wait( 245 struct xlog *log, 246 struct xlog_grant_head *head, 247 struct xlog_ticket *tic, 248 int need_bytes) __releases(&head->lock) 249 __acquires(&head->lock) 250 { 251 list_add_tail(&tic->t_queue, &head->waiters); 252 253 do { 254 if (XLOG_FORCED_SHUTDOWN(log)) 255 goto shutdown; 256 xlog_grant_push_ail(log, need_bytes); 257 258 __set_current_state(TASK_UNINTERRUPTIBLE); 259 spin_unlock(&head->lock); 260 261 XFS_STATS_INC(log->l_mp, xs_sleep_logspace); 262 263 trace_xfs_log_grant_sleep(log, tic); 264 schedule(); 265 trace_xfs_log_grant_wake(log, tic); 266 267 spin_lock(&head->lock); 268 if (XLOG_FORCED_SHUTDOWN(log)) 269 goto shutdown; 270 } while (xlog_space_left(log, &head->grant) < need_bytes); 271 272 list_del_init(&tic->t_queue); 273 return 0; 274 shutdown: 275 list_del_init(&tic->t_queue); 276 return -EIO; 277 } 278 279 /* 280 * Atomically get the log space required for a log ticket. 281 * 282 * Once a ticket gets put onto head->waiters, it will only return after the 283 * needed reservation is satisfied. 284 * 285 * This function is structured so that it has a lock free fast path. This is 286 * necessary because every new transaction reservation will come through this 287 * path. Hence any lock will be globally hot if we take it unconditionally on 288 * every pass. 289 * 290 * As tickets are only ever moved on and off head->waiters under head->lock, we 291 * only need to take that lock if we are going to add the ticket to the queue 292 * and sleep. We can avoid taking the lock if the ticket was never added to 293 * head->waiters because the t_queue list head will be empty and we hold the 294 * only reference to it so it can safely be checked unlocked. 295 */ 296 STATIC int 297 xlog_grant_head_check( 298 struct xlog *log, 299 struct xlog_grant_head *head, 300 struct xlog_ticket *tic, 301 int *need_bytes) 302 { 303 int free_bytes; 304 int error = 0; 305 306 ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY)); 307 308 /* 309 * If there are other waiters on the queue then give them a chance at 310 * logspace before us. Wake up the first waiters, if we do not wake 311 * up all the waiters then go to sleep waiting for more free space, 312 * otherwise try to get some space for this transaction. 313 */ 314 *need_bytes = xlog_ticket_reservation(log, head, tic); 315 free_bytes = xlog_space_left(log, &head->grant); 316 if (!list_empty_careful(&head->waiters)) { 317 spin_lock(&head->lock); 318 if (!xlog_grant_head_wake(log, head, &free_bytes) || 319 free_bytes < *need_bytes) { 320 error = xlog_grant_head_wait(log, head, tic, 321 *need_bytes); 322 } 323 spin_unlock(&head->lock); 324 } else if (free_bytes < *need_bytes) { 325 spin_lock(&head->lock); 326 error = xlog_grant_head_wait(log, head, tic, *need_bytes); 327 spin_unlock(&head->lock); 328 } 329 330 return error; 331 } 332 333 static void 334 xlog_tic_reset_res(xlog_ticket_t *tic) 335 { 336 tic->t_res_num = 0; 337 tic->t_res_arr_sum = 0; 338 tic->t_res_num_ophdrs = 0; 339 } 340 341 static void 342 xlog_tic_add_region(xlog_ticket_t *tic, uint len, uint type) 343 { 344 if (tic->t_res_num == XLOG_TIC_LEN_MAX) { 345 /* add to overflow and start again */ 346 tic->t_res_o_flow += tic->t_res_arr_sum; 347 tic->t_res_num = 0; 348 tic->t_res_arr_sum = 0; 349 } 350 351 tic->t_res_arr[tic->t_res_num].r_len = len; 352 tic->t_res_arr[tic->t_res_num].r_type = type; 353 tic->t_res_arr_sum += len; 354 tic->t_res_num++; 355 } 356 357 /* 358 * Replenish the byte reservation required by moving the grant write head. 359 */ 360 int 361 xfs_log_regrant( 362 struct xfs_mount *mp, 363 struct xlog_ticket *tic) 364 { 365 struct xlog *log = mp->m_log; 366 int need_bytes; 367 int error = 0; 368 369 if (XLOG_FORCED_SHUTDOWN(log)) 370 return -EIO; 371 372 XFS_STATS_INC(mp, xs_try_logspace); 373 374 /* 375 * This is a new transaction on the ticket, so we need to change the 376 * transaction ID so that the next transaction has a different TID in 377 * the log. Just add one to the existing tid so that we can see chains 378 * of rolling transactions in the log easily. 379 */ 380 tic->t_tid++; 381 382 xlog_grant_push_ail(log, tic->t_unit_res); 383 384 tic->t_curr_res = tic->t_unit_res; 385 xlog_tic_reset_res(tic); 386 387 if (tic->t_cnt > 0) 388 return 0; 389 390 trace_xfs_log_regrant(log, tic); 391 392 error = xlog_grant_head_check(log, &log->l_write_head, tic, 393 &need_bytes); 394 if (error) 395 goto out_error; 396 397 xlog_grant_add_space(log, &log->l_write_head.grant, need_bytes); 398 trace_xfs_log_regrant_exit(log, tic); 399 xlog_verify_grant_tail(log); 400 return 0; 401 402 out_error: 403 /* 404 * If we are failing, make sure the ticket doesn't have any current 405 * reservations. We don't want to add this back when the ticket/ 406 * transaction gets cancelled. 407 */ 408 tic->t_curr_res = 0; 409 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */ 410 return error; 411 } 412 413 /* 414 * Reserve log space and return a ticket corresponding to the reservation. 415 * 416 * Each reservation is going to reserve extra space for a log record header. 417 * When writes happen to the on-disk log, we don't subtract the length of the 418 * log record header from any reservation. By wasting space in each 419 * reservation, we prevent over allocation problems. 420 */ 421 int 422 xfs_log_reserve( 423 struct xfs_mount *mp, 424 int unit_bytes, 425 int cnt, 426 struct xlog_ticket **ticp, 427 uint8_t client, 428 bool permanent) 429 { 430 struct xlog *log = mp->m_log; 431 struct xlog_ticket *tic; 432 int need_bytes; 433 int error = 0; 434 435 ASSERT(client == XFS_TRANSACTION || client == XFS_LOG); 436 437 if (XLOG_FORCED_SHUTDOWN(log)) 438 return -EIO; 439 440 XFS_STATS_INC(mp, xs_try_logspace); 441 442 ASSERT(*ticp == NULL); 443 tic = xlog_ticket_alloc(log, unit_bytes, cnt, client, permanent, 444 KM_SLEEP | KM_MAYFAIL); 445 if (!tic) 446 return -ENOMEM; 447 448 *ticp = tic; 449 450 xlog_grant_push_ail(log, tic->t_cnt ? tic->t_unit_res * tic->t_cnt 451 : tic->t_unit_res); 452 453 trace_xfs_log_reserve(log, tic); 454 455 error = xlog_grant_head_check(log, &log->l_reserve_head, tic, 456 &need_bytes); 457 if (error) 458 goto out_error; 459 460 xlog_grant_add_space(log, &log->l_reserve_head.grant, need_bytes); 461 xlog_grant_add_space(log, &log->l_write_head.grant, need_bytes); 462 trace_xfs_log_reserve_exit(log, tic); 463 xlog_verify_grant_tail(log); 464 return 0; 465 466 out_error: 467 /* 468 * If we are failing, make sure the ticket doesn't have any current 469 * reservations. We don't want to add this back when the ticket/ 470 * transaction gets cancelled. 471 */ 472 tic->t_curr_res = 0; 473 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */ 474 return error; 475 } 476 477 478 /* 479 * NOTES: 480 * 481 * 1. currblock field gets updated at startup and after in-core logs 482 * marked as with WANT_SYNC. 483 */ 484 485 /* 486 * This routine is called when a user of a log manager ticket is done with 487 * the reservation. If the ticket was ever used, then a commit record for 488 * the associated transaction is written out as a log operation header with 489 * no data. The flag XLOG_TIC_INITED is set when the first write occurs with 490 * a given ticket. If the ticket was one with a permanent reservation, then 491 * a few operations are done differently. Permanent reservation tickets by 492 * default don't release the reservation. They just commit the current 493 * transaction with the belief that the reservation is still needed. A flag 494 * must be passed in before permanent reservations are actually released. 495 * When these type of tickets are not released, they need to be set into 496 * the inited state again. By doing this, a start record will be written 497 * out when the next write occurs. 498 */ 499 xfs_lsn_t 500 xfs_log_done( 501 struct xfs_mount *mp, 502 struct xlog_ticket *ticket, 503 struct xlog_in_core **iclog, 504 bool regrant) 505 { 506 struct xlog *log = mp->m_log; 507 xfs_lsn_t lsn = 0; 508 509 if (XLOG_FORCED_SHUTDOWN(log) || 510 /* 511 * If nothing was ever written, don't write out commit record. 512 * If we get an error, just continue and give back the log ticket. 513 */ 514 (((ticket->t_flags & XLOG_TIC_INITED) == 0) && 515 (xlog_commit_record(log, ticket, iclog, &lsn)))) { 516 lsn = (xfs_lsn_t) -1; 517 regrant = false; 518 } 519 520 521 if (!regrant) { 522 trace_xfs_log_done_nonperm(log, ticket); 523 524 /* 525 * Release ticket if not permanent reservation or a specific 526 * request has been made to release a permanent reservation. 527 */ 528 xlog_ungrant_log_space(log, ticket); 529 } else { 530 trace_xfs_log_done_perm(log, ticket); 531 532 xlog_regrant_reserve_log_space(log, ticket); 533 /* If this ticket was a permanent reservation and we aren't 534 * trying to release it, reset the inited flags; so next time 535 * we write, a start record will be written out. 536 */ 537 ticket->t_flags |= XLOG_TIC_INITED; 538 } 539 540 xfs_log_ticket_put(ticket); 541 return lsn; 542 } 543 544 /* 545 * Attaches a new iclog I/O completion callback routine during 546 * transaction commit. If the log is in error state, a non-zero 547 * return code is handed back and the caller is responsible for 548 * executing the callback at an appropriate time. 549 */ 550 int 551 xfs_log_notify( 552 struct xlog_in_core *iclog, 553 xfs_log_callback_t *cb) 554 { 555 int abortflg; 556 557 spin_lock(&iclog->ic_callback_lock); 558 abortflg = (iclog->ic_state & XLOG_STATE_IOERROR); 559 if (!abortflg) { 560 ASSERT_ALWAYS((iclog->ic_state == XLOG_STATE_ACTIVE) || 561 (iclog->ic_state == XLOG_STATE_WANT_SYNC)); 562 cb->cb_next = NULL; 563 *(iclog->ic_callback_tail) = cb; 564 iclog->ic_callback_tail = &(cb->cb_next); 565 } 566 spin_unlock(&iclog->ic_callback_lock); 567 return abortflg; 568 } 569 570 int 571 xfs_log_release_iclog( 572 struct xfs_mount *mp, 573 struct xlog_in_core *iclog) 574 { 575 if (xlog_state_release_iclog(mp->m_log, iclog)) { 576 xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR); 577 return -EIO; 578 } 579 580 return 0; 581 } 582 583 /* 584 * Mount a log filesystem 585 * 586 * mp - ubiquitous xfs mount point structure 587 * log_target - buftarg of on-disk log device 588 * blk_offset - Start block # where block size is 512 bytes (BBSIZE) 589 * num_bblocks - Number of BBSIZE blocks in on-disk log 590 * 591 * Return error or zero. 592 */ 593 int 594 xfs_log_mount( 595 xfs_mount_t *mp, 596 xfs_buftarg_t *log_target, 597 xfs_daddr_t blk_offset, 598 int num_bblks) 599 { 600 bool fatal = xfs_sb_version_hascrc(&mp->m_sb); 601 int error = 0; 602 int min_logfsbs; 603 604 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) { 605 xfs_notice(mp, "Mounting V%d Filesystem", 606 XFS_SB_VERSION_NUM(&mp->m_sb)); 607 } else { 608 xfs_notice(mp, 609 "Mounting V%d filesystem in no-recovery mode. Filesystem will be inconsistent.", 610 XFS_SB_VERSION_NUM(&mp->m_sb)); 611 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY); 612 } 613 614 mp->m_log = xlog_alloc_log(mp, log_target, blk_offset, num_bblks); 615 if (IS_ERR(mp->m_log)) { 616 error = PTR_ERR(mp->m_log); 617 goto out; 618 } 619 620 /* 621 * Validate the given log space and drop a critical message via syslog 622 * if the log size is too small that would lead to some unexpected 623 * situations in transaction log space reservation stage. 624 * 625 * Note: we can't just reject the mount if the validation fails. This 626 * would mean that people would have to downgrade their kernel just to 627 * remedy the situation as there is no way to grow the log (short of 628 * black magic surgery with xfs_db). 629 * 630 * We can, however, reject mounts for CRC format filesystems, as the 631 * mkfs binary being used to make the filesystem should never create a 632 * filesystem with a log that is too small. 633 */ 634 min_logfsbs = xfs_log_calc_minimum_size(mp); 635 636 if (mp->m_sb.sb_logblocks < min_logfsbs) { 637 xfs_warn(mp, 638 "Log size %d blocks too small, minimum size is %d blocks", 639 mp->m_sb.sb_logblocks, min_logfsbs); 640 error = -EINVAL; 641 } else if (mp->m_sb.sb_logblocks > XFS_MAX_LOG_BLOCKS) { 642 xfs_warn(mp, 643 "Log size %d blocks too large, maximum size is %lld blocks", 644 mp->m_sb.sb_logblocks, XFS_MAX_LOG_BLOCKS); 645 error = -EINVAL; 646 } else if (XFS_FSB_TO_B(mp, mp->m_sb.sb_logblocks) > XFS_MAX_LOG_BYTES) { 647 xfs_warn(mp, 648 "log size %lld bytes too large, maximum size is %lld bytes", 649 XFS_FSB_TO_B(mp, mp->m_sb.sb_logblocks), 650 XFS_MAX_LOG_BYTES); 651 error = -EINVAL; 652 } else if (mp->m_sb.sb_logsunit > 1 && 653 mp->m_sb.sb_logsunit % mp->m_sb.sb_blocksize) { 654 xfs_warn(mp, 655 "log stripe unit %u bytes must be a multiple of block size", 656 mp->m_sb.sb_logsunit); 657 error = -EINVAL; 658 fatal = true; 659 } 660 if (error) { 661 /* 662 * Log check errors are always fatal on v5; or whenever bad 663 * metadata leads to a crash. 664 */ 665 if (fatal) { 666 xfs_crit(mp, "AAIEEE! Log failed size checks. Abort!"); 667 ASSERT(0); 668 goto out_free_log; 669 } 670 xfs_crit(mp, "Log size out of supported range."); 671 xfs_crit(mp, 672 "Continuing onwards, but if log hangs are experienced then please report this message in the bug report."); 673 } 674 675 /* 676 * Initialize the AIL now we have a log. 677 */ 678 error = xfs_trans_ail_init(mp); 679 if (error) { 680 xfs_warn(mp, "AIL initialisation failed: error %d", error); 681 goto out_free_log; 682 } 683 mp->m_log->l_ailp = mp->m_ail; 684 685 /* 686 * skip log recovery on a norecovery mount. pretend it all 687 * just worked. 688 */ 689 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) { 690 int readonly = (mp->m_flags & XFS_MOUNT_RDONLY); 691 692 if (readonly) 693 mp->m_flags &= ~XFS_MOUNT_RDONLY; 694 695 error = xlog_recover(mp->m_log); 696 697 if (readonly) 698 mp->m_flags |= XFS_MOUNT_RDONLY; 699 if (error) { 700 xfs_warn(mp, "log mount/recovery failed: error %d", 701 error); 702 xlog_recover_cancel(mp->m_log); 703 goto out_destroy_ail; 704 } 705 } 706 707 error = xfs_sysfs_init(&mp->m_log->l_kobj, &xfs_log_ktype, &mp->m_kobj, 708 "log"); 709 if (error) 710 goto out_destroy_ail; 711 712 /* Normal transactions can now occur */ 713 mp->m_log->l_flags &= ~XLOG_ACTIVE_RECOVERY; 714 715 /* 716 * Now the log has been fully initialised and we know were our 717 * space grant counters are, we can initialise the permanent ticket 718 * needed for delayed logging to work. 719 */ 720 xlog_cil_init_post_recovery(mp->m_log); 721 722 return 0; 723 724 out_destroy_ail: 725 xfs_trans_ail_destroy(mp); 726 out_free_log: 727 xlog_dealloc_log(mp->m_log); 728 out: 729 return error; 730 } 731 732 /* 733 * Finish the recovery of the file system. This is separate from the 734 * xfs_log_mount() call, because it depends on the code in xfs_mountfs() to read 735 * in the root and real-time bitmap inodes between calling xfs_log_mount() and 736 * here. 737 * 738 * If we finish recovery successfully, start the background log work. If we are 739 * not doing recovery, then we have a RO filesystem and we don't need to start 740 * it. 741 */ 742 int 743 xfs_log_mount_finish( 744 struct xfs_mount *mp) 745 { 746 int error = 0; 747 bool readonly = (mp->m_flags & XFS_MOUNT_RDONLY); 748 bool recovered = mp->m_log->l_flags & XLOG_RECOVERY_NEEDED; 749 750 if (mp->m_flags & XFS_MOUNT_NORECOVERY) { 751 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY); 752 return 0; 753 } else if (readonly) { 754 /* Allow unlinked processing to proceed */ 755 mp->m_flags &= ~XFS_MOUNT_RDONLY; 756 } 757 758 /* 759 * During the second phase of log recovery, we need iget and 760 * iput to behave like they do for an active filesystem. 761 * xfs_fs_drop_inode needs to be able to prevent the deletion 762 * of inodes before we're done replaying log items on those 763 * inodes. Turn it off immediately after recovery finishes 764 * so that we don't leak the quota inodes if subsequent mount 765 * activities fail. 766 * 767 * We let all inodes involved in redo item processing end up on 768 * the LRU instead of being evicted immediately so that if we do 769 * something to an unlinked inode, the irele won't cause 770 * premature truncation and freeing of the inode, which results 771 * in log recovery failure. We have to evict the unreferenced 772 * lru inodes after clearing SB_ACTIVE because we don't 773 * otherwise clean up the lru if there's a subsequent failure in 774 * xfs_mountfs, which leads to us leaking the inodes if nothing 775 * else (e.g. quotacheck) references the inodes before the 776 * mount failure occurs. 777 */ 778 mp->m_super->s_flags |= SB_ACTIVE; 779 error = xlog_recover_finish(mp->m_log); 780 if (!error) 781 xfs_log_work_queue(mp); 782 mp->m_super->s_flags &= ~SB_ACTIVE; 783 evict_inodes(mp->m_super); 784 785 /* 786 * Drain the buffer LRU after log recovery. This is required for v4 787 * filesystems to avoid leaving around buffers with NULL verifier ops, 788 * but we do it unconditionally to make sure we're always in a clean 789 * cache state after mount. 790 * 791 * Don't push in the error case because the AIL may have pending intents 792 * that aren't removed until recovery is cancelled. 793 */ 794 if (!error && recovered) { 795 xfs_log_force(mp, XFS_LOG_SYNC); 796 xfs_ail_push_all_sync(mp->m_ail); 797 } 798 xfs_wait_buftarg(mp->m_ddev_targp); 799 800 if (readonly) 801 mp->m_flags |= XFS_MOUNT_RDONLY; 802 803 return error; 804 } 805 806 /* 807 * The mount has failed. Cancel the recovery if it hasn't completed and destroy 808 * the log. 809 */ 810 int 811 xfs_log_mount_cancel( 812 struct xfs_mount *mp) 813 { 814 int error; 815 816 error = xlog_recover_cancel(mp->m_log); 817 xfs_log_unmount(mp); 818 819 return error; 820 } 821 822 /* 823 * Final log writes as part of unmount. 824 * 825 * Mark the filesystem clean as unmount happens. Note that during relocation 826 * this routine needs to be executed as part of source-bag while the 827 * deallocation must not be done until source-end. 828 */ 829 830 /* Actually write the unmount record to disk. */ 831 static void 832 xfs_log_write_unmount_record( 833 struct xfs_mount *mp) 834 { 835 /* the data section must be 32 bit size aligned */ 836 struct xfs_unmount_log_format magic = { 837 .magic = XLOG_UNMOUNT_TYPE, 838 }; 839 struct xfs_log_iovec reg = { 840 .i_addr = &magic, 841 .i_len = sizeof(magic), 842 .i_type = XLOG_REG_TYPE_UNMOUNT, 843 }; 844 struct xfs_log_vec vec = { 845 .lv_niovecs = 1, 846 .lv_iovecp = ®, 847 }; 848 struct xlog *log = mp->m_log; 849 struct xlog_in_core *iclog; 850 struct xlog_ticket *tic = NULL; 851 xfs_lsn_t lsn; 852 uint flags = XLOG_UNMOUNT_TRANS; 853 int error; 854 855 error = xfs_log_reserve(mp, 600, 1, &tic, XFS_LOG, 0); 856 if (error) 857 goto out_err; 858 859 /* 860 * If we think the summary counters are bad, clear the unmount header 861 * flag in the unmount record so that the summary counters will be 862 * recalculated during log recovery at next mount. Refer to 863 * xlog_check_unmount_rec for more details. 864 */ 865 if (XFS_TEST_ERROR(xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS), mp, 866 XFS_ERRTAG_FORCE_SUMMARY_RECALC)) { 867 xfs_alert(mp, "%s: will fix summary counters at next mount", 868 __func__); 869 flags &= ~XLOG_UNMOUNT_TRANS; 870 } 871 872 /* remove inited flag, and account for space used */ 873 tic->t_flags = 0; 874 tic->t_curr_res -= sizeof(magic); 875 error = xlog_write(log, &vec, tic, &lsn, NULL, flags); 876 /* 877 * At this point, we're umounting anyway, so there's no point in 878 * transitioning log state to IOERROR. Just continue... 879 */ 880 out_err: 881 if (error) 882 xfs_alert(mp, "%s: unmount record failed", __func__); 883 884 spin_lock(&log->l_icloglock); 885 iclog = log->l_iclog; 886 atomic_inc(&iclog->ic_refcnt); 887 xlog_state_want_sync(log, iclog); 888 spin_unlock(&log->l_icloglock); 889 error = xlog_state_release_iclog(log, iclog); 890 891 spin_lock(&log->l_icloglock); 892 switch (iclog->ic_state) { 893 default: 894 if (!XLOG_FORCED_SHUTDOWN(log)) { 895 xlog_wait(&iclog->ic_force_wait, &log->l_icloglock); 896 break; 897 } 898 /* fall through */ 899 case XLOG_STATE_ACTIVE: 900 case XLOG_STATE_DIRTY: 901 spin_unlock(&log->l_icloglock); 902 break; 903 } 904 905 if (tic) { 906 trace_xfs_log_umount_write(log, tic); 907 xlog_ungrant_log_space(log, tic); 908 xfs_log_ticket_put(tic); 909 } 910 } 911 912 /* 913 * Unmount record used to have a string "Unmount filesystem--" in the 914 * data section where the "Un" was really a magic number (XLOG_UNMOUNT_TYPE). 915 * We just write the magic number now since that particular field isn't 916 * currently architecture converted and "Unmount" is a bit foo. 917 * As far as I know, there weren't any dependencies on the old behaviour. 918 */ 919 920 static int 921 xfs_log_unmount_write(xfs_mount_t *mp) 922 { 923 struct xlog *log = mp->m_log; 924 xlog_in_core_t *iclog; 925 #ifdef DEBUG 926 xlog_in_core_t *first_iclog; 927 #endif 928 int error; 929 930 /* 931 * Don't write out unmount record on norecovery mounts or ro devices. 932 * Or, if we are doing a forced umount (typically because of IO errors). 933 */ 934 if (mp->m_flags & XFS_MOUNT_NORECOVERY || 935 xfs_readonly_buftarg(log->l_mp->m_logdev_targp)) { 936 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY); 937 return 0; 938 } 939 940 error = xfs_log_force(mp, XFS_LOG_SYNC); 941 ASSERT(error || !(XLOG_FORCED_SHUTDOWN(log))); 942 943 #ifdef DEBUG 944 first_iclog = iclog = log->l_iclog; 945 do { 946 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) { 947 ASSERT(iclog->ic_state & XLOG_STATE_ACTIVE); 948 ASSERT(iclog->ic_offset == 0); 949 } 950 iclog = iclog->ic_next; 951 } while (iclog != first_iclog); 952 #endif 953 if (! (XLOG_FORCED_SHUTDOWN(log))) { 954 xfs_log_write_unmount_record(mp); 955 } else { 956 /* 957 * We're already in forced_shutdown mode, couldn't 958 * even attempt to write out the unmount transaction. 959 * 960 * Go through the motions of sync'ing and releasing 961 * the iclog, even though no I/O will actually happen, 962 * we need to wait for other log I/Os that may already 963 * be in progress. Do this as a separate section of 964 * code so we'll know if we ever get stuck here that 965 * we're in this odd situation of trying to unmount 966 * a file system that went into forced_shutdown as 967 * the result of an unmount.. 968 */ 969 spin_lock(&log->l_icloglock); 970 iclog = log->l_iclog; 971 atomic_inc(&iclog->ic_refcnt); 972 973 xlog_state_want_sync(log, iclog); 974 spin_unlock(&log->l_icloglock); 975 error = xlog_state_release_iclog(log, iclog); 976 977 spin_lock(&log->l_icloglock); 978 979 if ( ! ( iclog->ic_state == XLOG_STATE_ACTIVE 980 || iclog->ic_state == XLOG_STATE_DIRTY 981 || iclog->ic_state == XLOG_STATE_IOERROR) ) { 982 983 xlog_wait(&iclog->ic_force_wait, 984 &log->l_icloglock); 985 } else { 986 spin_unlock(&log->l_icloglock); 987 } 988 } 989 990 return error; 991 } /* xfs_log_unmount_write */ 992 993 /* 994 * Empty the log for unmount/freeze. 995 * 996 * To do this, we first need to shut down the background log work so it is not 997 * trying to cover the log as we clean up. We then need to unpin all objects in 998 * the log so we can then flush them out. Once they have completed their IO and 999 * run the callbacks removing themselves from the AIL, we can write the unmount 1000 * record. 1001 */ 1002 void 1003 xfs_log_quiesce( 1004 struct xfs_mount *mp) 1005 { 1006 cancel_delayed_work_sync(&mp->m_log->l_work); 1007 xfs_log_force(mp, XFS_LOG_SYNC); 1008 1009 /* 1010 * The superblock buffer is uncached and while xfs_ail_push_all_sync() 1011 * will push it, xfs_wait_buftarg() will not wait for it. Further, 1012 * xfs_buf_iowait() cannot be used because it was pushed with the 1013 * XBF_ASYNC flag set, so we need to use a lock/unlock pair to wait for 1014 * the IO to complete. 1015 */ 1016 xfs_ail_push_all_sync(mp->m_ail); 1017 xfs_wait_buftarg(mp->m_ddev_targp); 1018 xfs_buf_lock(mp->m_sb_bp); 1019 xfs_buf_unlock(mp->m_sb_bp); 1020 1021 xfs_log_unmount_write(mp); 1022 } 1023 1024 /* 1025 * Shut down and release the AIL and Log. 1026 * 1027 * During unmount, we need to ensure we flush all the dirty metadata objects 1028 * from the AIL so that the log is empty before we write the unmount record to 1029 * the log. Once this is done, we can tear down the AIL and the log. 1030 */ 1031 void 1032 xfs_log_unmount( 1033 struct xfs_mount *mp) 1034 { 1035 xfs_log_quiesce(mp); 1036 1037 xfs_trans_ail_destroy(mp); 1038 1039 xfs_sysfs_del(&mp->m_log->l_kobj); 1040 1041 xlog_dealloc_log(mp->m_log); 1042 } 1043 1044 void 1045 xfs_log_item_init( 1046 struct xfs_mount *mp, 1047 struct xfs_log_item *item, 1048 int type, 1049 const struct xfs_item_ops *ops) 1050 { 1051 item->li_mountp = mp; 1052 item->li_ailp = mp->m_ail; 1053 item->li_type = type; 1054 item->li_ops = ops; 1055 item->li_lv = NULL; 1056 1057 INIT_LIST_HEAD(&item->li_ail); 1058 INIT_LIST_HEAD(&item->li_cil); 1059 INIT_LIST_HEAD(&item->li_bio_list); 1060 INIT_LIST_HEAD(&item->li_trans); 1061 } 1062 1063 /* 1064 * Wake up processes waiting for log space after we have moved the log tail. 1065 */ 1066 void 1067 xfs_log_space_wake( 1068 struct xfs_mount *mp) 1069 { 1070 struct xlog *log = mp->m_log; 1071 int free_bytes; 1072 1073 if (XLOG_FORCED_SHUTDOWN(log)) 1074 return; 1075 1076 if (!list_empty_careful(&log->l_write_head.waiters)) { 1077 ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY)); 1078 1079 spin_lock(&log->l_write_head.lock); 1080 free_bytes = xlog_space_left(log, &log->l_write_head.grant); 1081 xlog_grant_head_wake(log, &log->l_write_head, &free_bytes); 1082 spin_unlock(&log->l_write_head.lock); 1083 } 1084 1085 if (!list_empty_careful(&log->l_reserve_head.waiters)) { 1086 ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY)); 1087 1088 spin_lock(&log->l_reserve_head.lock); 1089 free_bytes = xlog_space_left(log, &log->l_reserve_head.grant); 1090 xlog_grant_head_wake(log, &log->l_reserve_head, &free_bytes); 1091 spin_unlock(&log->l_reserve_head.lock); 1092 } 1093 } 1094 1095 /* 1096 * Determine if we have a transaction that has gone to disk that needs to be 1097 * covered. To begin the transition to the idle state firstly the log needs to 1098 * be idle. That means the CIL, the AIL and the iclogs needs to be empty before 1099 * we start attempting to cover the log. 1100 * 1101 * Only if we are then in a state where covering is needed, the caller is 1102 * informed that dummy transactions are required to move the log into the idle 1103 * state. 1104 * 1105 * If there are any items in the AIl or CIL, then we do not want to attempt to 1106 * cover the log as we may be in a situation where there isn't log space 1107 * available to run a dummy transaction and this can lead to deadlocks when the 1108 * tail of the log is pinned by an item that is modified in the CIL. Hence 1109 * there's no point in running a dummy transaction at this point because we 1110 * can't start trying to idle the log until both the CIL and AIL are empty. 1111 */ 1112 static int 1113 xfs_log_need_covered(xfs_mount_t *mp) 1114 { 1115 struct xlog *log = mp->m_log; 1116 int needed = 0; 1117 1118 if (!xfs_fs_writable(mp, SB_FREEZE_WRITE)) 1119 return 0; 1120 1121 if (!xlog_cil_empty(log)) 1122 return 0; 1123 1124 spin_lock(&log->l_icloglock); 1125 switch (log->l_covered_state) { 1126 case XLOG_STATE_COVER_DONE: 1127 case XLOG_STATE_COVER_DONE2: 1128 case XLOG_STATE_COVER_IDLE: 1129 break; 1130 case XLOG_STATE_COVER_NEED: 1131 case XLOG_STATE_COVER_NEED2: 1132 if (xfs_ail_min_lsn(log->l_ailp)) 1133 break; 1134 if (!xlog_iclogs_empty(log)) 1135 break; 1136 1137 needed = 1; 1138 if (log->l_covered_state == XLOG_STATE_COVER_NEED) 1139 log->l_covered_state = XLOG_STATE_COVER_DONE; 1140 else 1141 log->l_covered_state = XLOG_STATE_COVER_DONE2; 1142 break; 1143 default: 1144 needed = 1; 1145 break; 1146 } 1147 spin_unlock(&log->l_icloglock); 1148 return needed; 1149 } 1150 1151 /* 1152 * We may be holding the log iclog lock upon entering this routine. 1153 */ 1154 xfs_lsn_t 1155 xlog_assign_tail_lsn_locked( 1156 struct xfs_mount *mp) 1157 { 1158 struct xlog *log = mp->m_log; 1159 struct xfs_log_item *lip; 1160 xfs_lsn_t tail_lsn; 1161 1162 assert_spin_locked(&mp->m_ail->ail_lock); 1163 1164 /* 1165 * To make sure we always have a valid LSN for the log tail we keep 1166 * track of the last LSN which was committed in log->l_last_sync_lsn, 1167 * and use that when the AIL was empty. 1168 */ 1169 lip = xfs_ail_min(mp->m_ail); 1170 if (lip) 1171 tail_lsn = lip->li_lsn; 1172 else 1173 tail_lsn = atomic64_read(&log->l_last_sync_lsn); 1174 trace_xfs_log_assign_tail_lsn(log, tail_lsn); 1175 atomic64_set(&log->l_tail_lsn, tail_lsn); 1176 return tail_lsn; 1177 } 1178 1179 xfs_lsn_t 1180 xlog_assign_tail_lsn( 1181 struct xfs_mount *mp) 1182 { 1183 xfs_lsn_t tail_lsn; 1184 1185 spin_lock(&mp->m_ail->ail_lock); 1186 tail_lsn = xlog_assign_tail_lsn_locked(mp); 1187 spin_unlock(&mp->m_ail->ail_lock); 1188 1189 return tail_lsn; 1190 } 1191 1192 /* 1193 * Return the space in the log between the tail and the head. The head 1194 * is passed in the cycle/bytes formal parms. In the special case where 1195 * the reserve head has wrapped passed the tail, this calculation is no 1196 * longer valid. In this case, just return 0 which means there is no space 1197 * in the log. This works for all places where this function is called 1198 * with the reserve head. Of course, if the write head were to ever 1199 * wrap the tail, we should blow up. Rather than catch this case here, 1200 * we depend on other ASSERTions in other parts of the code. XXXmiken 1201 * 1202 * This code also handles the case where the reservation head is behind 1203 * the tail. The details of this case are described below, but the end 1204 * result is that we return the size of the log as the amount of space left. 1205 */ 1206 STATIC int 1207 xlog_space_left( 1208 struct xlog *log, 1209 atomic64_t *head) 1210 { 1211 int free_bytes; 1212 int tail_bytes; 1213 int tail_cycle; 1214 int head_cycle; 1215 int head_bytes; 1216 1217 xlog_crack_grant_head(head, &head_cycle, &head_bytes); 1218 xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_bytes); 1219 tail_bytes = BBTOB(tail_bytes); 1220 if (tail_cycle == head_cycle && head_bytes >= tail_bytes) 1221 free_bytes = log->l_logsize - (head_bytes - tail_bytes); 1222 else if (tail_cycle + 1 < head_cycle) 1223 return 0; 1224 else if (tail_cycle < head_cycle) { 1225 ASSERT(tail_cycle == (head_cycle - 1)); 1226 free_bytes = tail_bytes - head_bytes; 1227 } else { 1228 /* 1229 * The reservation head is behind the tail. 1230 * In this case we just want to return the size of the 1231 * log as the amount of space left. 1232 */ 1233 xfs_alert(log->l_mp, "xlog_space_left: head behind tail"); 1234 xfs_alert(log->l_mp, 1235 " tail_cycle = %d, tail_bytes = %d", 1236 tail_cycle, tail_bytes); 1237 xfs_alert(log->l_mp, 1238 " GH cycle = %d, GH bytes = %d", 1239 head_cycle, head_bytes); 1240 ASSERT(0); 1241 free_bytes = log->l_logsize; 1242 } 1243 return free_bytes; 1244 } 1245 1246 1247 /* 1248 * Log function which is called when an io completes. 1249 * 1250 * The log manager needs its own routine, in order to control what 1251 * happens with the buffer after the write completes. 1252 */ 1253 static void 1254 xlog_iodone(xfs_buf_t *bp) 1255 { 1256 struct xlog_in_core *iclog = bp->b_log_item; 1257 struct xlog *l = iclog->ic_log; 1258 int aborted = 0; 1259 1260 /* 1261 * Race to shutdown the filesystem if we see an error or the iclog is in 1262 * IOABORT state. The IOABORT state is only set in DEBUG mode to inject 1263 * CRC errors into log recovery. 1264 */ 1265 if (XFS_TEST_ERROR(bp->b_error, l->l_mp, XFS_ERRTAG_IODONE_IOERR) || 1266 iclog->ic_state & XLOG_STATE_IOABORT) { 1267 if (iclog->ic_state & XLOG_STATE_IOABORT) 1268 iclog->ic_state &= ~XLOG_STATE_IOABORT; 1269 1270 xfs_buf_ioerror_alert(bp, __func__); 1271 xfs_buf_stale(bp); 1272 xfs_force_shutdown(l->l_mp, SHUTDOWN_LOG_IO_ERROR); 1273 /* 1274 * This flag will be propagated to the trans-committed 1275 * callback routines to let them know that the log-commit 1276 * didn't succeed. 1277 */ 1278 aborted = XFS_LI_ABORTED; 1279 } else if (iclog->ic_state & XLOG_STATE_IOERROR) { 1280 aborted = XFS_LI_ABORTED; 1281 } 1282 1283 /* log I/O is always issued ASYNC */ 1284 ASSERT(bp->b_flags & XBF_ASYNC); 1285 xlog_state_done_syncing(iclog, aborted); 1286 1287 /* 1288 * drop the buffer lock now that we are done. Nothing references 1289 * the buffer after this, so an unmount waiting on this lock can now 1290 * tear it down safely. As such, it is unsafe to reference the buffer 1291 * (bp) after the unlock as we could race with it being freed. 1292 */ 1293 xfs_buf_unlock(bp); 1294 } 1295 1296 /* 1297 * Return size of each in-core log record buffer. 1298 * 1299 * All machines get 8 x 32kB buffers by default, unless tuned otherwise. 1300 * 1301 * If the filesystem blocksize is too large, we may need to choose a 1302 * larger size since the directory code currently logs entire blocks. 1303 */ 1304 1305 STATIC void 1306 xlog_get_iclog_buffer_size( 1307 struct xfs_mount *mp, 1308 struct xlog *log) 1309 { 1310 int size; 1311 int xhdrs; 1312 1313 if (mp->m_logbufs <= 0) 1314 log->l_iclog_bufs = XLOG_MAX_ICLOGS; 1315 else 1316 log->l_iclog_bufs = mp->m_logbufs; 1317 1318 /* 1319 * Buffer size passed in from mount system call. 1320 */ 1321 if (mp->m_logbsize > 0) { 1322 size = log->l_iclog_size = mp->m_logbsize; 1323 log->l_iclog_size_log = 0; 1324 while (size != 1) { 1325 log->l_iclog_size_log++; 1326 size >>= 1; 1327 } 1328 1329 if (xfs_sb_version_haslogv2(&mp->m_sb)) { 1330 /* # headers = size / 32k 1331 * one header holds cycles from 32k of data 1332 */ 1333 1334 xhdrs = mp->m_logbsize / XLOG_HEADER_CYCLE_SIZE; 1335 if (mp->m_logbsize % XLOG_HEADER_CYCLE_SIZE) 1336 xhdrs++; 1337 log->l_iclog_hsize = xhdrs << BBSHIFT; 1338 log->l_iclog_heads = xhdrs; 1339 } else { 1340 ASSERT(mp->m_logbsize <= XLOG_BIG_RECORD_BSIZE); 1341 log->l_iclog_hsize = BBSIZE; 1342 log->l_iclog_heads = 1; 1343 } 1344 goto done; 1345 } 1346 1347 /* All machines use 32kB buffers by default. */ 1348 log->l_iclog_size = XLOG_BIG_RECORD_BSIZE; 1349 log->l_iclog_size_log = XLOG_BIG_RECORD_BSHIFT; 1350 1351 /* the default log size is 16k or 32k which is one header sector */ 1352 log->l_iclog_hsize = BBSIZE; 1353 log->l_iclog_heads = 1; 1354 1355 done: 1356 /* are we being asked to make the sizes selected above visible? */ 1357 if (mp->m_logbufs == 0) 1358 mp->m_logbufs = log->l_iclog_bufs; 1359 if (mp->m_logbsize == 0) 1360 mp->m_logbsize = log->l_iclog_size; 1361 } /* xlog_get_iclog_buffer_size */ 1362 1363 1364 void 1365 xfs_log_work_queue( 1366 struct xfs_mount *mp) 1367 { 1368 queue_delayed_work(mp->m_sync_workqueue, &mp->m_log->l_work, 1369 msecs_to_jiffies(xfs_syncd_centisecs * 10)); 1370 } 1371 1372 /* 1373 * Every sync period we need to unpin all items in the AIL and push them to 1374 * disk. If there is nothing dirty, then we might need to cover the log to 1375 * indicate that the filesystem is idle. 1376 */ 1377 static void 1378 xfs_log_worker( 1379 struct work_struct *work) 1380 { 1381 struct xlog *log = container_of(to_delayed_work(work), 1382 struct xlog, l_work); 1383 struct xfs_mount *mp = log->l_mp; 1384 1385 /* dgc: errors ignored - not fatal and nowhere to report them */ 1386 if (xfs_log_need_covered(mp)) { 1387 /* 1388 * Dump a transaction into the log that contains no real change. 1389 * This is needed to stamp the current tail LSN into the log 1390 * during the covering operation. 1391 * 1392 * We cannot use an inode here for this - that will push dirty 1393 * state back up into the VFS and then periodic inode flushing 1394 * will prevent log covering from making progress. Hence we 1395 * synchronously log the superblock instead to ensure the 1396 * superblock is immediately unpinned and can be written back. 1397 */ 1398 xfs_sync_sb(mp, true); 1399 } else 1400 xfs_log_force(mp, 0); 1401 1402 /* start pushing all the metadata that is currently dirty */ 1403 xfs_ail_push_all(mp->m_ail); 1404 1405 /* queue us up again */ 1406 xfs_log_work_queue(mp); 1407 } 1408 1409 /* 1410 * This routine initializes some of the log structure for a given mount point. 1411 * Its primary purpose is to fill in enough, so recovery can occur. However, 1412 * some other stuff may be filled in too. 1413 */ 1414 STATIC struct xlog * 1415 xlog_alloc_log( 1416 struct xfs_mount *mp, 1417 struct xfs_buftarg *log_target, 1418 xfs_daddr_t blk_offset, 1419 int num_bblks) 1420 { 1421 struct xlog *log; 1422 xlog_rec_header_t *head; 1423 xlog_in_core_t **iclogp; 1424 xlog_in_core_t *iclog, *prev_iclog=NULL; 1425 xfs_buf_t *bp; 1426 int i; 1427 int error = -ENOMEM; 1428 uint log2_size = 0; 1429 1430 log = kmem_zalloc(sizeof(struct xlog), KM_MAYFAIL); 1431 if (!log) { 1432 xfs_warn(mp, "Log allocation failed: No memory!"); 1433 goto out; 1434 } 1435 1436 log->l_mp = mp; 1437 log->l_targ = log_target; 1438 log->l_logsize = BBTOB(num_bblks); 1439 log->l_logBBstart = blk_offset; 1440 log->l_logBBsize = num_bblks; 1441 log->l_covered_state = XLOG_STATE_COVER_IDLE; 1442 log->l_flags |= XLOG_ACTIVE_RECOVERY; 1443 INIT_DELAYED_WORK(&log->l_work, xfs_log_worker); 1444 1445 log->l_prev_block = -1; 1446 /* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */ 1447 xlog_assign_atomic_lsn(&log->l_tail_lsn, 1, 0); 1448 xlog_assign_atomic_lsn(&log->l_last_sync_lsn, 1, 0); 1449 log->l_curr_cycle = 1; /* 0 is bad since this is initial value */ 1450 1451 xlog_grant_head_init(&log->l_reserve_head); 1452 xlog_grant_head_init(&log->l_write_head); 1453 1454 error = -EFSCORRUPTED; 1455 if (xfs_sb_version_hassector(&mp->m_sb)) { 1456 log2_size = mp->m_sb.sb_logsectlog; 1457 if (log2_size < BBSHIFT) { 1458 xfs_warn(mp, "Log sector size too small (0x%x < 0x%x)", 1459 log2_size, BBSHIFT); 1460 goto out_free_log; 1461 } 1462 1463 log2_size -= BBSHIFT; 1464 if (log2_size > mp->m_sectbb_log) { 1465 xfs_warn(mp, "Log sector size too large (0x%x > 0x%x)", 1466 log2_size, mp->m_sectbb_log); 1467 goto out_free_log; 1468 } 1469 1470 /* for larger sector sizes, must have v2 or external log */ 1471 if (log2_size && log->l_logBBstart > 0 && 1472 !xfs_sb_version_haslogv2(&mp->m_sb)) { 1473 xfs_warn(mp, 1474 "log sector size (0x%x) invalid for configuration.", 1475 log2_size); 1476 goto out_free_log; 1477 } 1478 } 1479 log->l_sectBBsize = 1 << log2_size; 1480 1481 xlog_get_iclog_buffer_size(mp, log); 1482 1483 /* 1484 * Use a NULL block for the extra log buffer used during splits so that 1485 * it will trigger errors if we ever try to do IO on it without first 1486 * having set it up properly. 1487 */ 1488 error = -ENOMEM; 1489 bp = xfs_buf_alloc(mp->m_logdev_targp, XFS_BUF_DADDR_NULL, 1490 BTOBB(log->l_iclog_size), XBF_NO_IOACCT); 1491 if (!bp) 1492 goto out_free_log; 1493 1494 /* 1495 * The iclogbuf buffer locks are held over IO but we are not going to do 1496 * IO yet. Hence unlock the buffer so that the log IO path can grab it 1497 * when appropriately. 1498 */ 1499 ASSERT(xfs_buf_islocked(bp)); 1500 xfs_buf_unlock(bp); 1501 1502 /* use high priority wq for log I/O completion */ 1503 bp->b_ioend_wq = mp->m_log_workqueue; 1504 bp->b_iodone = xlog_iodone; 1505 log->l_xbuf = bp; 1506 1507 spin_lock_init(&log->l_icloglock); 1508 init_waitqueue_head(&log->l_flush_wait); 1509 1510 iclogp = &log->l_iclog; 1511 /* 1512 * The amount of memory to allocate for the iclog structure is 1513 * rather funky due to the way the structure is defined. It is 1514 * done this way so that we can use different sizes for machines 1515 * with different amounts of memory. See the definition of 1516 * xlog_in_core_t in xfs_log_priv.h for details. 1517 */ 1518 ASSERT(log->l_iclog_size >= 4096); 1519 for (i=0; i < log->l_iclog_bufs; i++) { 1520 *iclogp = kmem_zalloc(sizeof(xlog_in_core_t), KM_MAYFAIL); 1521 if (!*iclogp) 1522 goto out_free_iclog; 1523 1524 iclog = *iclogp; 1525 iclog->ic_prev = prev_iclog; 1526 prev_iclog = iclog; 1527 1528 bp = xfs_buf_get_uncached(mp->m_logdev_targp, 1529 BTOBB(log->l_iclog_size), 1530 XBF_NO_IOACCT); 1531 if (!bp) 1532 goto out_free_iclog; 1533 1534 ASSERT(xfs_buf_islocked(bp)); 1535 xfs_buf_unlock(bp); 1536 1537 /* use high priority wq for log I/O completion */ 1538 bp->b_ioend_wq = mp->m_log_workqueue; 1539 bp->b_iodone = xlog_iodone; 1540 iclog->ic_bp = bp; 1541 iclog->ic_data = bp->b_addr; 1542 #ifdef DEBUG 1543 log->l_iclog_bak[i] = &iclog->ic_header; 1544 #endif 1545 head = &iclog->ic_header; 1546 memset(head, 0, sizeof(xlog_rec_header_t)); 1547 head->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM); 1548 head->h_version = cpu_to_be32( 1549 xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1); 1550 head->h_size = cpu_to_be32(log->l_iclog_size); 1551 /* new fields */ 1552 head->h_fmt = cpu_to_be32(XLOG_FMT); 1553 memcpy(&head->h_fs_uuid, &mp->m_sb.sb_uuid, sizeof(uuid_t)); 1554 1555 iclog->ic_size = BBTOB(bp->b_length) - log->l_iclog_hsize; 1556 iclog->ic_state = XLOG_STATE_ACTIVE; 1557 iclog->ic_log = log; 1558 atomic_set(&iclog->ic_refcnt, 0); 1559 spin_lock_init(&iclog->ic_callback_lock); 1560 iclog->ic_callback_tail = &(iclog->ic_callback); 1561 iclog->ic_datap = (char *)iclog->ic_data + log->l_iclog_hsize; 1562 1563 init_waitqueue_head(&iclog->ic_force_wait); 1564 init_waitqueue_head(&iclog->ic_write_wait); 1565 1566 iclogp = &iclog->ic_next; 1567 } 1568 *iclogp = log->l_iclog; /* complete ring */ 1569 log->l_iclog->ic_prev = prev_iclog; /* re-write 1st prev ptr */ 1570 1571 error = xlog_cil_init(log); 1572 if (error) 1573 goto out_free_iclog; 1574 return log; 1575 1576 out_free_iclog: 1577 for (iclog = log->l_iclog; iclog; iclog = prev_iclog) { 1578 prev_iclog = iclog->ic_next; 1579 if (iclog->ic_bp) 1580 xfs_buf_free(iclog->ic_bp); 1581 kmem_free(iclog); 1582 } 1583 spinlock_destroy(&log->l_icloglock); 1584 xfs_buf_free(log->l_xbuf); 1585 out_free_log: 1586 kmem_free(log); 1587 out: 1588 return ERR_PTR(error); 1589 } /* xlog_alloc_log */ 1590 1591 1592 /* 1593 * Write out the commit record of a transaction associated with the given 1594 * ticket. Return the lsn of the commit record. 1595 */ 1596 STATIC int 1597 xlog_commit_record( 1598 struct xlog *log, 1599 struct xlog_ticket *ticket, 1600 struct xlog_in_core **iclog, 1601 xfs_lsn_t *commitlsnp) 1602 { 1603 struct xfs_mount *mp = log->l_mp; 1604 int error; 1605 struct xfs_log_iovec reg = { 1606 .i_addr = NULL, 1607 .i_len = 0, 1608 .i_type = XLOG_REG_TYPE_COMMIT, 1609 }; 1610 struct xfs_log_vec vec = { 1611 .lv_niovecs = 1, 1612 .lv_iovecp = ®, 1613 }; 1614 1615 ASSERT_ALWAYS(iclog); 1616 error = xlog_write(log, &vec, ticket, commitlsnp, iclog, 1617 XLOG_COMMIT_TRANS); 1618 if (error) 1619 xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR); 1620 return error; 1621 } 1622 1623 /* 1624 * Push on the buffer cache code if we ever use more than 75% of the on-disk 1625 * log space. This code pushes on the lsn which would supposedly free up 1626 * the 25% which we want to leave free. We may need to adopt a policy which 1627 * pushes on an lsn which is further along in the log once we reach the high 1628 * water mark. In this manner, we would be creating a low water mark. 1629 */ 1630 STATIC void 1631 xlog_grant_push_ail( 1632 struct xlog *log, 1633 int need_bytes) 1634 { 1635 xfs_lsn_t threshold_lsn = 0; 1636 xfs_lsn_t last_sync_lsn; 1637 int free_blocks; 1638 int free_bytes; 1639 int threshold_block; 1640 int threshold_cycle; 1641 int free_threshold; 1642 1643 ASSERT(BTOBB(need_bytes) < log->l_logBBsize); 1644 1645 free_bytes = xlog_space_left(log, &log->l_reserve_head.grant); 1646 free_blocks = BTOBBT(free_bytes); 1647 1648 /* 1649 * Set the threshold for the minimum number of free blocks in the 1650 * log to the maximum of what the caller needs, one quarter of the 1651 * log, and 256 blocks. 1652 */ 1653 free_threshold = BTOBB(need_bytes); 1654 free_threshold = max(free_threshold, (log->l_logBBsize >> 2)); 1655 free_threshold = max(free_threshold, 256); 1656 if (free_blocks >= free_threshold) 1657 return; 1658 1659 xlog_crack_atomic_lsn(&log->l_tail_lsn, &threshold_cycle, 1660 &threshold_block); 1661 threshold_block += free_threshold; 1662 if (threshold_block >= log->l_logBBsize) { 1663 threshold_block -= log->l_logBBsize; 1664 threshold_cycle += 1; 1665 } 1666 threshold_lsn = xlog_assign_lsn(threshold_cycle, 1667 threshold_block); 1668 /* 1669 * Don't pass in an lsn greater than the lsn of the last 1670 * log record known to be on disk. Use a snapshot of the last sync lsn 1671 * so that it doesn't change between the compare and the set. 1672 */ 1673 last_sync_lsn = atomic64_read(&log->l_last_sync_lsn); 1674 if (XFS_LSN_CMP(threshold_lsn, last_sync_lsn) > 0) 1675 threshold_lsn = last_sync_lsn; 1676 1677 /* 1678 * Get the transaction layer to kick the dirty buffers out to 1679 * disk asynchronously. No point in trying to do this if 1680 * the filesystem is shutting down. 1681 */ 1682 if (!XLOG_FORCED_SHUTDOWN(log)) 1683 xfs_ail_push(log->l_ailp, threshold_lsn); 1684 } 1685 1686 /* 1687 * Stamp cycle number in every block 1688 */ 1689 STATIC void 1690 xlog_pack_data( 1691 struct xlog *log, 1692 struct xlog_in_core *iclog, 1693 int roundoff) 1694 { 1695 int i, j, k; 1696 int size = iclog->ic_offset + roundoff; 1697 __be32 cycle_lsn; 1698 char *dp; 1699 1700 cycle_lsn = CYCLE_LSN_DISK(iclog->ic_header.h_lsn); 1701 1702 dp = iclog->ic_datap; 1703 for (i = 0; i < BTOBB(size); i++) { 1704 if (i >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) 1705 break; 1706 iclog->ic_header.h_cycle_data[i] = *(__be32 *)dp; 1707 *(__be32 *)dp = cycle_lsn; 1708 dp += BBSIZE; 1709 } 1710 1711 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) { 1712 xlog_in_core_2_t *xhdr = iclog->ic_data; 1713 1714 for ( ; i < BTOBB(size); i++) { 1715 j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 1716 k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 1717 xhdr[j].hic_xheader.xh_cycle_data[k] = *(__be32 *)dp; 1718 *(__be32 *)dp = cycle_lsn; 1719 dp += BBSIZE; 1720 } 1721 1722 for (i = 1; i < log->l_iclog_heads; i++) 1723 xhdr[i].hic_xheader.xh_cycle = cycle_lsn; 1724 } 1725 } 1726 1727 /* 1728 * Calculate the checksum for a log buffer. 1729 * 1730 * This is a little more complicated than it should be because the various 1731 * headers and the actual data are non-contiguous. 1732 */ 1733 __le32 1734 xlog_cksum( 1735 struct xlog *log, 1736 struct xlog_rec_header *rhead, 1737 char *dp, 1738 int size) 1739 { 1740 uint32_t crc; 1741 1742 /* first generate the crc for the record header ... */ 1743 crc = xfs_start_cksum_update((char *)rhead, 1744 sizeof(struct xlog_rec_header), 1745 offsetof(struct xlog_rec_header, h_crc)); 1746 1747 /* ... then for additional cycle data for v2 logs ... */ 1748 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) { 1749 union xlog_in_core2 *xhdr = (union xlog_in_core2 *)rhead; 1750 int i; 1751 int xheads; 1752 1753 xheads = size / XLOG_HEADER_CYCLE_SIZE; 1754 if (size % XLOG_HEADER_CYCLE_SIZE) 1755 xheads++; 1756 1757 for (i = 1; i < xheads; i++) { 1758 crc = crc32c(crc, &xhdr[i].hic_xheader, 1759 sizeof(struct xlog_rec_ext_header)); 1760 } 1761 } 1762 1763 /* ... and finally for the payload */ 1764 crc = crc32c(crc, dp, size); 1765 1766 return xfs_end_cksum(crc); 1767 } 1768 1769 /* 1770 * The bdstrat callback function for log bufs. This gives us a central 1771 * place to trap bufs in case we get hit by a log I/O error and need to 1772 * shutdown. Actually, in practice, even when we didn't get a log error, 1773 * we transition the iclogs to IOERROR state *after* flushing all existing 1774 * iclogs to disk. This is because we don't want anymore new transactions to be 1775 * started or completed afterwards. 1776 * 1777 * We lock the iclogbufs here so that we can serialise against IO completion 1778 * during unmount. We might be processing a shutdown triggered during unmount, 1779 * and that can occur asynchronously to the unmount thread, and hence we need to 1780 * ensure that completes before tearing down the iclogbufs. Hence we need to 1781 * hold the buffer lock across the log IO to acheive that. 1782 */ 1783 STATIC int 1784 xlog_bdstrat( 1785 struct xfs_buf *bp) 1786 { 1787 struct xlog_in_core *iclog = bp->b_log_item; 1788 1789 xfs_buf_lock(bp); 1790 if (iclog->ic_state & XLOG_STATE_IOERROR) { 1791 xfs_buf_ioerror(bp, -EIO); 1792 xfs_buf_stale(bp); 1793 xfs_buf_ioend(bp); 1794 /* 1795 * It would seem logical to return EIO here, but we rely on 1796 * the log state machine to propagate I/O errors instead of 1797 * doing it here. Similarly, IO completion will unlock the 1798 * buffer, so we don't do it here. 1799 */ 1800 return 0; 1801 } 1802 1803 xfs_buf_submit(bp); 1804 return 0; 1805 } 1806 1807 /* 1808 * Flush out the in-core log (iclog) to the on-disk log in an asynchronous 1809 * fashion. Previously, we should have moved the current iclog 1810 * ptr in the log to point to the next available iclog. This allows further 1811 * write to continue while this code syncs out an iclog ready to go. 1812 * Before an in-core log can be written out, the data section must be scanned 1813 * to save away the 1st word of each BBSIZE block into the header. We replace 1814 * it with the current cycle count. Each BBSIZE block is tagged with the 1815 * cycle count because there in an implicit assumption that drives will 1816 * guarantee that entire 512 byte blocks get written at once. In other words, 1817 * we can't have part of a 512 byte block written and part not written. By 1818 * tagging each block, we will know which blocks are valid when recovering 1819 * after an unclean shutdown. 1820 * 1821 * This routine is single threaded on the iclog. No other thread can be in 1822 * this routine with the same iclog. Changing contents of iclog can there- 1823 * fore be done without grabbing the state machine lock. Updating the global 1824 * log will require grabbing the lock though. 1825 * 1826 * The entire log manager uses a logical block numbering scheme. Only 1827 * log_sync (and then only bwrite()) know about the fact that the log may 1828 * not start with block zero on a given device. The log block start offset 1829 * is added immediately before calling bwrite(). 1830 */ 1831 1832 STATIC int 1833 xlog_sync( 1834 struct xlog *log, 1835 struct xlog_in_core *iclog) 1836 { 1837 xfs_buf_t *bp; 1838 int i; 1839 uint count; /* byte count of bwrite */ 1840 uint count_init; /* initial count before roundup */ 1841 int roundoff; /* roundoff to BB or stripe */ 1842 int split = 0; /* split write into two regions */ 1843 int error; 1844 int v2 = xfs_sb_version_haslogv2(&log->l_mp->m_sb); 1845 int size; 1846 1847 XFS_STATS_INC(log->l_mp, xs_log_writes); 1848 ASSERT(atomic_read(&iclog->ic_refcnt) == 0); 1849 1850 /* Add for LR header */ 1851 count_init = log->l_iclog_hsize + iclog->ic_offset; 1852 1853 /* Round out the log write size */ 1854 if (v2 && log->l_mp->m_sb.sb_logsunit > 1) { 1855 /* we have a v2 stripe unit to use */ 1856 count = XLOG_LSUNITTOB(log, XLOG_BTOLSUNIT(log, count_init)); 1857 } else { 1858 count = BBTOB(BTOBB(count_init)); 1859 } 1860 roundoff = count - count_init; 1861 ASSERT(roundoff >= 0); 1862 ASSERT((v2 && log->l_mp->m_sb.sb_logsunit > 1 && 1863 roundoff < log->l_mp->m_sb.sb_logsunit) 1864 || 1865 (log->l_mp->m_sb.sb_logsunit <= 1 && 1866 roundoff < BBTOB(1))); 1867 1868 /* move grant heads by roundoff in sync */ 1869 xlog_grant_add_space(log, &log->l_reserve_head.grant, roundoff); 1870 xlog_grant_add_space(log, &log->l_write_head.grant, roundoff); 1871 1872 /* put cycle number in every block */ 1873 xlog_pack_data(log, iclog, roundoff); 1874 1875 /* real byte length */ 1876 size = iclog->ic_offset; 1877 if (v2) 1878 size += roundoff; 1879 iclog->ic_header.h_len = cpu_to_be32(size); 1880 1881 bp = iclog->ic_bp; 1882 XFS_BUF_SET_ADDR(bp, BLOCK_LSN(be64_to_cpu(iclog->ic_header.h_lsn))); 1883 1884 XFS_STATS_ADD(log->l_mp, xs_log_blocks, BTOBB(count)); 1885 1886 /* Do we need to split this write into 2 parts? */ 1887 if (XFS_BUF_ADDR(bp) + BTOBB(count) > log->l_logBBsize) { 1888 char *dptr; 1889 1890 split = count - (BBTOB(log->l_logBBsize - XFS_BUF_ADDR(bp))); 1891 count = BBTOB(log->l_logBBsize - XFS_BUF_ADDR(bp)); 1892 iclog->ic_bwritecnt = 2; 1893 1894 /* 1895 * Bump the cycle numbers at the start of each block in the 1896 * part of the iclog that ends up in the buffer that gets 1897 * written to the start of the log. 1898 * 1899 * Watch out for the header magic number case, though. 1900 */ 1901 dptr = (char *)&iclog->ic_header + count; 1902 for (i = 0; i < split; i += BBSIZE) { 1903 uint32_t cycle = be32_to_cpu(*(__be32 *)dptr); 1904 if (++cycle == XLOG_HEADER_MAGIC_NUM) 1905 cycle++; 1906 *(__be32 *)dptr = cpu_to_be32(cycle); 1907 1908 dptr += BBSIZE; 1909 } 1910 } else { 1911 iclog->ic_bwritecnt = 1; 1912 } 1913 1914 /* calculcate the checksum */ 1915 iclog->ic_header.h_crc = xlog_cksum(log, &iclog->ic_header, 1916 iclog->ic_datap, size); 1917 /* 1918 * Intentionally corrupt the log record CRC based on the error injection 1919 * frequency, if defined. This facilitates testing log recovery in the 1920 * event of torn writes. Hence, set the IOABORT state to abort the log 1921 * write on I/O completion and shutdown the fs. The subsequent mount 1922 * detects the bad CRC and attempts to recover. 1923 */ 1924 if (XFS_TEST_ERROR(false, log->l_mp, XFS_ERRTAG_LOG_BAD_CRC)) { 1925 iclog->ic_header.h_crc &= cpu_to_le32(0xAAAAAAAA); 1926 iclog->ic_state |= XLOG_STATE_IOABORT; 1927 xfs_warn(log->l_mp, 1928 "Intentionally corrupted log record at LSN 0x%llx. Shutdown imminent.", 1929 be64_to_cpu(iclog->ic_header.h_lsn)); 1930 } 1931 1932 bp->b_io_length = BTOBB(count); 1933 bp->b_log_item = iclog; 1934 bp->b_flags &= ~XBF_FLUSH; 1935 bp->b_flags |= (XBF_ASYNC | XBF_SYNCIO | XBF_WRITE | XBF_FUA); 1936 1937 /* 1938 * Flush the data device before flushing the log to make sure all meta 1939 * data written back from the AIL actually made it to disk before 1940 * stamping the new log tail LSN into the log buffer. For an external 1941 * log we need to issue the flush explicitly, and unfortunately 1942 * synchronously here; for an internal log we can simply use the block 1943 * layer state machine for preflushes. 1944 */ 1945 if (log->l_mp->m_logdev_targp != log->l_mp->m_ddev_targp) 1946 xfs_blkdev_issue_flush(log->l_mp->m_ddev_targp); 1947 else 1948 bp->b_flags |= XBF_FLUSH; 1949 1950 ASSERT(XFS_BUF_ADDR(bp) <= log->l_logBBsize-1); 1951 ASSERT(XFS_BUF_ADDR(bp) + BTOBB(count) <= log->l_logBBsize); 1952 1953 xlog_verify_iclog(log, iclog, count, true); 1954 1955 /* account for log which doesn't start at block #0 */ 1956 XFS_BUF_SET_ADDR(bp, XFS_BUF_ADDR(bp) + log->l_logBBstart); 1957 1958 /* 1959 * Don't call xfs_bwrite here. We do log-syncs even when the filesystem 1960 * is shutting down. 1961 */ 1962 error = xlog_bdstrat(bp); 1963 if (error) { 1964 xfs_buf_ioerror_alert(bp, "xlog_sync"); 1965 return error; 1966 } 1967 if (split) { 1968 bp = iclog->ic_log->l_xbuf; 1969 XFS_BUF_SET_ADDR(bp, 0); /* logical 0 */ 1970 xfs_buf_associate_memory(bp, 1971 (char *)&iclog->ic_header + count, split); 1972 bp->b_log_item = iclog; 1973 bp->b_flags &= ~XBF_FLUSH; 1974 bp->b_flags |= (XBF_ASYNC | XBF_SYNCIO | XBF_WRITE | XBF_FUA); 1975 1976 ASSERT(XFS_BUF_ADDR(bp) <= log->l_logBBsize-1); 1977 ASSERT(XFS_BUF_ADDR(bp) + BTOBB(count) <= log->l_logBBsize); 1978 1979 /* account for internal log which doesn't start at block #0 */ 1980 XFS_BUF_SET_ADDR(bp, XFS_BUF_ADDR(bp) + log->l_logBBstart); 1981 error = xlog_bdstrat(bp); 1982 if (error) { 1983 xfs_buf_ioerror_alert(bp, "xlog_sync (split)"); 1984 return error; 1985 } 1986 } 1987 return 0; 1988 } /* xlog_sync */ 1989 1990 /* 1991 * Deallocate a log structure 1992 */ 1993 STATIC void 1994 xlog_dealloc_log( 1995 struct xlog *log) 1996 { 1997 xlog_in_core_t *iclog, *next_iclog; 1998 int i; 1999 2000 xlog_cil_destroy(log); 2001 2002 /* 2003 * Cycle all the iclogbuf locks to make sure all log IO completion 2004 * is done before we tear down these buffers. 2005 */ 2006 iclog = log->l_iclog; 2007 for (i = 0; i < log->l_iclog_bufs; i++) { 2008 xfs_buf_lock(iclog->ic_bp); 2009 xfs_buf_unlock(iclog->ic_bp); 2010 iclog = iclog->ic_next; 2011 } 2012 2013 /* 2014 * Always need to ensure that the extra buffer does not point to memory 2015 * owned by another log buffer before we free it. Also, cycle the lock 2016 * first to ensure we've completed IO on it. 2017 */ 2018 xfs_buf_lock(log->l_xbuf); 2019 xfs_buf_unlock(log->l_xbuf); 2020 xfs_buf_set_empty(log->l_xbuf, BTOBB(log->l_iclog_size)); 2021 xfs_buf_free(log->l_xbuf); 2022 2023 iclog = log->l_iclog; 2024 for (i = 0; i < log->l_iclog_bufs; i++) { 2025 xfs_buf_free(iclog->ic_bp); 2026 next_iclog = iclog->ic_next; 2027 kmem_free(iclog); 2028 iclog = next_iclog; 2029 } 2030 spinlock_destroy(&log->l_icloglock); 2031 2032 log->l_mp->m_log = NULL; 2033 kmem_free(log); 2034 } /* xlog_dealloc_log */ 2035 2036 /* 2037 * Update counters atomically now that memcpy is done. 2038 */ 2039 /* ARGSUSED */ 2040 static inline void 2041 xlog_state_finish_copy( 2042 struct xlog *log, 2043 struct xlog_in_core *iclog, 2044 int record_cnt, 2045 int copy_bytes) 2046 { 2047 spin_lock(&log->l_icloglock); 2048 2049 be32_add_cpu(&iclog->ic_header.h_num_logops, record_cnt); 2050 iclog->ic_offset += copy_bytes; 2051 2052 spin_unlock(&log->l_icloglock); 2053 } /* xlog_state_finish_copy */ 2054 2055 2056 2057 2058 /* 2059 * print out info relating to regions written which consume 2060 * the reservation 2061 */ 2062 void 2063 xlog_print_tic_res( 2064 struct xfs_mount *mp, 2065 struct xlog_ticket *ticket) 2066 { 2067 uint i; 2068 uint ophdr_spc = ticket->t_res_num_ophdrs * (uint)sizeof(xlog_op_header_t); 2069 2070 /* match with XLOG_REG_TYPE_* in xfs_log.h */ 2071 #define REG_TYPE_STR(type, str) [XLOG_REG_TYPE_##type] = str 2072 static char *res_type_str[] = { 2073 REG_TYPE_STR(BFORMAT, "bformat"), 2074 REG_TYPE_STR(BCHUNK, "bchunk"), 2075 REG_TYPE_STR(EFI_FORMAT, "efi_format"), 2076 REG_TYPE_STR(EFD_FORMAT, "efd_format"), 2077 REG_TYPE_STR(IFORMAT, "iformat"), 2078 REG_TYPE_STR(ICORE, "icore"), 2079 REG_TYPE_STR(IEXT, "iext"), 2080 REG_TYPE_STR(IBROOT, "ibroot"), 2081 REG_TYPE_STR(ILOCAL, "ilocal"), 2082 REG_TYPE_STR(IATTR_EXT, "iattr_ext"), 2083 REG_TYPE_STR(IATTR_BROOT, "iattr_broot"), 2084 REG_TYPE_STR(IATTR_LOCAL, "iattr_local"), 2085 REG_TYPE_STR(QFORMAT, "qformat"), 2086 REG_TYPE_STR(DQUOT, "dquot"), 2087 REG_TYPE_STR(QUOTAOFF, "quotaoff"), 2088 REG_TYPE_STR(LRHEADER, "LR header"), 2089 REG_TYPE_STR(UNMOUNT, "unmount"), 2090 REG_TYPE_STR(COMMIT, "commit"), 2091 REG_TYPE_STR(TRANSHDR, "trans header"), 2092 REG_TYPE_STR(ICREATE, "inode create"), 2093 REG_TYPE_STR(RUI_FORMAT, "rui_format"), 2094 REG_TYPE_STR(RUD_FORMAT, "rud_format"), 2095 REG_TYPE_STR(CUI_FORMAT, "cui_format"), 2096 REG_TYPE_STR(CUD_FORMAT, "cud_format"), 2097 REG_TYPE_STR(BUI_FORMAT, "bui_format"), 2098 REG_TYPE_STR(BUD_FORMAT, "bud_format"), 2099 }; 2100 BUILD_BUG_ON(ARRAY_SIZE(res_type_str) != XLOG_REG_TYPE_MAX + 1); 2101 #undef REG_TYPE_STR 2102 2103 xfs_warn(mp, "ticket reservation summary:"); 2104 xfs_warn(mp, " unit res = %d bytes", 2105 ticket->t_unit_res); 2106 xfs_warn(mp, " current res = %d bytes", 2107 ticket->t_curr_res); 2108 xfs_warn(mp, " total reg = %u bytes (o/flow = %u bytes)", 2109 ticket->t_res_arr_sum, ticket->t_res_o_flow); 2110 xfs_warn(mp, " ophdrs = %u (ophdr space = %u bytes)", 2111 ticket->t_res_num_ophdrs, ophdr_spc); 2112 xfs_warn(mp, " ophdr + reg = %u bytes", 2113 ticket->t_res_arr_sum + ticket->t_res_o_flow + ophdr_spc); 2114 xfs_warn(mp, " num regions = %u", 2115 ticket->t_res_num); 2116 2117 for (i = 0; i < ticket->t_res_num; i++) { 2118 uint r_type = ticket->t_res_arr[i].r_type; 2119 xfs_warn(mp, "region[%u]: %s - %u bytes", i, 2120 ((r_type <= 0 || r_type > XLOG_REG_TYPE_MAX) ? 2121 "bad-rtype" : res_type_str[r_type]), 2122 ticket->t_res_arr[i].r_len); 2123 } 2124 } 2125 2126 /* 2127 * Print a summary of the transaction. 2128 */ 2129 void 2130 xlog_print_trans( 2131 struct xfs_trans *tp) 2132 { 2133 struct xfs_mount *mp = tp->t_mountp; 2134 struct xfs_log_item *lip; 2135 2136 /* dump core transaction and ticket info */ 2137 xfs_warn(mp, "transaction summary:"); 2138 xfs_warn(mp, " log res = %d", tp->t_log_res); 2139 xfs_warn(mp, " log count = %d", tp->t_log_count); 2140 xfs_warn(mp, " flags = 0x%x", tp->t_flags); 2141 2142 xlog_print_tic_res(mp, tp->t_ticket); 2143 2144 /* dump each log item */ 2145 list_for_each_entry(lip, &tp->t_items, li_trans) { 2146 struct xfs_log_vec *lv = lip->li_lv; 2147 struct xfs_log_iovec *vec; 2148 int i; 2149 2150 xfs_warn(mp, "log item: "); 2151 xfs_warn(mp, " type = 0x%x", lip->li_type); 2152 xfs_warn(mp, " flags = 0x%lx", lip->li_flags); 2153 if (!lv) 2154 continue; 2155 xfs_warn(mp, " niovecs = %d", lv->lv_niovecs); 2156 xfs_warn(mp, " size = %d", lv->lv_size); 2157 xfs_warn(mp, " bytes = %d", lv->lv_bytes); 2158 xfs_warn(mp, " buf len = %d", lv->lv_buf_len); 2159 2160 /* dump each iovec for the log item */ 2161 vec = lv->lv_iovecp; 2162 for (i = 0; i < lv->lv_niovecs; i++) { 2163 int dumplen = min(vec->i_len, 32); 2164 2165 xfs_warn(mp, " iovec[%d]", i); 2166 xfs_warn(mp, " type = 0x%x", vec->i_type); 2167 xfs_warn(mp, " len = %d", vec->i_len); 2168 xfs_warn(mp, " first %d bytes of iovec[%d]:", dumplen, i); 2169 xfs_hex_dump(vec->i_addr, dumplen); 2170 2171 vec++; 2172 } 2173 } 2174 } 2175 2176 /* 2177 * Calculate the potential space needed by the log vector. Each region gets 2178 * its own xlog_op_header_t and may need to be double word aligned. 2179 */ 2180 static int 2181 xlog_write_calc_vec_length( 2182 struct xlog_ticket *ticket, 2183 struct xfs_log_vec *log_vector) 2184 { 2185 struct xfs_log_vec *lv; 2186 int headers = 0; 2187 int len = 0; 2188 int i; 2189 2190 /* acct for start rec of xact */ 2191 if (ticket->t_flags & XLOG_TIC_INITED) 2192 headers++; 2193 2194 for (lv = log_vector; lv; lv = lv->lv_next) { 2195 /* we don't write ordered log vectors */ 2196 if (lv->lv_buf_len == XFS_LOG_VEC_ORDERED) 2197 continue; 2198 2199 headers += lv->lv_niovecs; 2200 2201 for (i = 0; i < lv->lv_niovecs; i++) { 2202 struct xfs_log_iovec *vecp = &lv->lv_iovecp[i]; 2203 2204 len += vecp->i_len; 2205 xlog_tic_add_region(ticket, vecp->i_len, vecp->i_type); 2206 } 2207 } 2208 2209 ticket->t_res_num_ophdrs += headers; 2210 len += headers * sizeof(struct xlog_op_header); 2211 2212 return len; 2213 } 2214 2215 /* 2216 * If first write for transaction, insert start record We can't be trying to 2217 * commit if we are inited. We can't have any "partial_copy" if we are inited. 2218 */ 2219 static int 2220 xlog_write_start_rec( 2221 struct xlog_op_header *ophdr, 2222 struct xlog_ticket *ticket) 2223 { 2224 if (!(ticket->t_flags & XLOG_TIC_INITED)) 2225 return 0; 2226 2227 ophdr->oh_tid = cpu_to_be32(ticket->t_tid); 2228 ophdr->oh_clientid = ticket->t_clientid; 2229 ophdr->oh_len = 0; 2230 ophdr->oh_flags = XLOG_START_TRANS; 2231 ophdr->oh_res2 = 0; 2232 2233 ticket->t_flags &= ~XLOG_TIC_INITED; 2234 2235 return sizeof(struct xlog_op_header); 2236 } 2237 2238 static xlog_op_header_t * 2239 xlog_write_setup_ophdr( 2240 struct xlog *log, 2241 struct xlog_op_header *ophdr, 2242 struct xlog_ticket *ticket, 2243 uint flags) 2244 { 2245 ophdr->oh_tid = cpu_to_be32(ticket->t_tid); 2246 ophdr->oh_clientid = ticket->t_clientid; 2247 ophdr->oh_res2 = 0; 2248 2249 /* are we copying a commit or unmount record? */ 2250 ophdr->oh_flags = flags; 2251 2252 /* 2253 * We've seen logs corrupted with bad transaction client ids. This 2254 * makes sure that XFS doesn't generate them on. Turn this into an EIO 2255 * and shut down the filesystem. 2256 */ 2257 switch (ophdr->oh_clientid) { 2258 case XFS_TRANSACTION: 2259 case XFS_VOLUME: 2260 case XFS_LOG: 2261 break; 2262 default: 2263 xfs_warn(log->l_mp, 2264 "Bad XFS transaction clientid 0x%x in ticket "PTR_FMT, 2265 ophdr->oh_clientid, ticket); 2266 return NULL; 2267 } 2268 2269 return ophdr; 2270 } 2271 2272 /* 2273 * Set up the parameters of the region copy into the log. This has 2274 * to handle region write split across multiple log buffers - this 2275 * state is kept external to this function so that this code can 2276 * be written in an obvious, self documenting manner. 2277 */ 2278 static int 2279 xlog_write_setup_copy( 2280 struct xlog_ticket *ticket, 2281 struct xlog_op_header *ophdr, 2282 int space_available, 2283 int space_required, 2284 int *copy_off, 2285 int *copy_len, 2286 int *last_was_partial_copy, 2287 int *bytes_consumed) 2288 { 2289 int still_to_copy; 2290 2291 still_to_copy = space_required - *bytes_consumed; 2292 *copy_off = *bytes_consumed; 2293 2294 if (still_to_copy <= space_available) { 2295 /* write of region completes here */ 2296 *copy_len = still_to_copy; 2297 ophdr->oh_len = cpu_to_be32(*copy_len); 2298 if (*last_was_partial_copy) 2299 ophdr->oh_flags |= (XLOG_END_TRANS|XLOG_WAS_CONT_TRANS); 2300 *last_was_partial_copy = 0; 2301 *bytes_consumed = 0; 2302 return 0; 2303 } 2304 2305 /* partial write of region, needs extra log op header reservation */ 2306 *copy_len = space_available; 2307 ophdr->oh_len = cpu_to_be32(*copy_len); 2308 ophdr->oh_flags |= XLOG_CONTINUE_TRANS; 2309 if (*last_was_partial_copy) 2310 ophdr->oh_flags |= XLOG_WAS_CONT_TRANS; 2311 *bytes_consumed += *copy_len; 2312 (*last_was_partial_copy)++; 2313 2314 /* account for new log op header */ 2315 ticket->t_curr_res -= sizeof(struct xlog_op_header); 2316 ticket->t_res_num_ophdrs++; 2317 2318 return sizeof(struct xlog_op_header); 2319 } 2320 2321 static int 2322 xlog_write_copy_finish( 2323 struct xlog *log, 2324 struct xlog_in_core *iclog, 2325 uint flags, 2326 int *record_cnt, 2327 int *data_cnt, 2328 int *partial_copy, 2329 int *partial_copy_len, 2330 int log_offset, 2331 struct xlog_in_core **commit_iclog) 2332 { 2333 if (*partial_copy) { 2334 /* 2335 * This iclog has already been marked WANT_SYNC by 2336 * xlog_state_get_iclog_space. 2337 */ 2338 xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt); 2339 *record_cnt = 0; 2340 *data_cnt = 0; 2341 return xlog_state_release_iclog(log, iclog); 2342 } 2343 2344 *partial_copy = 0; 2345 *partial_copy_len = 0; 2346 2347 if (iclog->ic_size - log_offset <= sizeof(xlog_op_header_t)) { 2348 /* no more space in this iclog - push it. */ 2349 xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt); 2350 *record_cnt = 0; 2351 *data_cnt = 0; 2352 2353 spin_lock(&log->l_icloglock); 2354 xlog_state_want_sync(log, iclog); 2355 spin_unlock(&log->l_icloglock); 2356 2357 if (!commit_iclog) 2358 return xlog_state_release_iclog(log, iclog); 2359 ASSERT(flags & XLOG_COMMIT_TRANS); 2360 *commit_iclog = iclog; 2361 } 2362 2363 return 0; 2364 } 2365 2366 /* 2367 * Write some region out to in-core log 2368 * 2369 * This will be called when writing externally provided regions or when 2370 * writing out a commit record for a given transaction. 2371 * 2372 * General algorithm: 2373 * 1. Find total length of this write. This may include adding to the 2374 * lengths passed in. 2375 * 2. Check whether we violate the tickets reservation. 2376 * 3. While writing to this iclog 2377 * A. Reserve as much space in this iclog as can get 2378 * B. If this is first write, save away start lsn 2379 * C. While writing this region: 2380 * 1. If first write of transaction, write start record 2381 * 2. Write log operation header (header per region) 2382 * 3. Find out if we can fit entire region into this iclog 2383 * 4. Potentially, verify destination memcpy ptr 2384 * 5. Memcpy (partial) region 2385 * 6. If partial copy, release iclog; otherwise, continue 2386 * copying more regions into current iclog 2387 * 4. Mark want sync bit (in simulation mode) 2388 * 5. Release iclog for potential flush to on-disk log. 2389 * 2390 * ERRORS: 2391 * 1. Panic if reservation is overrun. This should never happen since 2392 * reservation amounts are generated internal to the filesystem. 2393 * NOTES: 2394 * 1. Tickets are single threaded data structures. 2395 * 2. The XLOG_END_TRANS & XLOG_CONTINUE_TRANS flags are passed down to the 2396 * syncing routine. When a single log_write region needs to span 2397 * multiple in-core logs, the XLOG_CONTINUE_TRANS bit should be set 2398 * on all log operation writes which don't contain the end of the 2399 * region. The XLOG_END_TRANS bit is used for the in-core log 2400 * operation which contains the end of the continued log_write region. 2401 * 3. When xlog_state_get_iclog_space() grabs the rest of the current iclog, 2402 * we don't really know exactly how much space will be used. As a result, 2403 * we don't update ic_offset until the end when we know exactly how many 2404 * bytes have been written out. 2405 */ 2406 int 2407 xlog_write( 2408 struct xlog *log, 2409 struct xfs_log_vec *log_vector, 2410 struct xlog_ticket *ticket, 2411 xfs_lsn_t *start_lsn, 2412 struct xlog_in_core **commit_iclog, 2413 uint flags) 2414 { 2415 struct xlog_in_core *iclog = NULL; 2416 struct xfs_log_iovec *vecp; 2417 struct xfs_log_vec *lv; 2418 int len; 2419 int index; 2420 int partial_copy = 0; 2421 int partial_copy_len = 0; 2422 int contwr = 0; 2423 int record_cnt = 0; 2424 int data_cnt = 0; 2425 int error; 2426 2427 *start_lsn = 0; 2428 2429 len = xlog_write_calc_vec_length(ticket, log_vector); 2430 2431 /* 2432 * Region headers and bytes are already accounted for. 2433 * We only need to take into account start records and 2434 * split regions in this function. 2435 */ 2436 if (ticket->t_flags & XLOG_TIC_INITED) 2437 ticket->t_curr_res -= sizeof(xlog_op_header_t); 2438 2439 /* 2440 * Commit record headers need to be accounted for. These 2441 * come in as separate writes so are easy to detect. 2442 */ 2443 if (flags & (XLOG_COMMIT_TRANS | XLOG_UNMOUNT_TRANS)) 2444 ticket->t_curr_res -= sizeof(xlog_op_header_t); 2445 2446 if (ticket->t_curr_res < 0) { 2447 xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES, 2448 "ctx ticket reservation ran out. Need to up reservation"); 2449 xlog_print_tic_res(log->l_mp, ticket); 2450 xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR); 2451 } 2452 2453 index = 0; 2454 lv = log_vector; 2455 vecp = lv->lv_iovecp; 2456 while (lv && (!lv->lv_niovecs || index < lv->lv_niovecs)) { 2457 void *ptr; 2458 int log_offset; 2459 2460 error = xlog_state_get_iclog_space(log, len, &iclog, ticket, 2461 &contwr, &log_offset); 2462 if (error) 2463 return error; 2464 2465 ASSERT(log_offset <= iclog->ic_size - 1); 2466 ptr = iclog->ic_datap + log_offset; 2467 2468 /* start_lsn is the first lsn written to. That's all we need. */ 2469 if (!*start_lsn) 2470 *start_lsn = be64_to_cpu(iclog->ic_header.h_lsn); 2471 2472 /* 2473 * This loop writes out as many regions as can fit in the amount 2474 * of space which was allocated by xlog_state_get_iclog_space(). 2475 */ 2476 while (lv && (!lv->lv_niovecs || index < lv->lv_niovecs)) { 2477 struct xfs_log_iovec *reg; 2478 struct xlog_op_header *ophdr; 2479 int start_rec_copy; 2480 int copy_len; 2481 int copy_off; 2482 bool ordered = false; 2483 2484 /* ordered log vectors have no regions to write */ 2485 if (lv->lv_buf_len == XFS_LOG_VEC_ORDERED) { 2486 ASSERT(lv->lv_niovecs == 0); 2487 ordered = true; 2488 goto next_lv; 2489 } 2490 2491 reg = &vecp[index]; 2492 ASSERT(reg->i_len % sizeof(int32_t) == 0); 2493 ASSERT((unsigned long)ptr % sizeof(int32_t) == 0); 2494 2495 start_rec_copy = xlog_write_start_rec(ptr, ticket); 2496 if (start_rec_copy) { 2497 record_cnt++; 2498 xlog_write_adv_cnt(&ptr, &len, &log_offset, 2499 start_rec_copy); 2500 } 2501 2502 ophdr = xlog_write_setup_ophdr(log, ptr, ticket, flags); 2503 if (!ophdr) 2504 return -EIO; 2505 2506 xlog_write_adv_cnt(&ptr, &len, &log_offset, 2507 sizeof(struct xlog_op_header)); 2508 2509 len += xlog_write_setup_copy(ticket, ophdr, 2510 iclog->ic_size-log_offset, 2511 reg->i_len, 2512 ©_off, ©_len, 2513 &partial_copy, 2514 &partial_copy_len); 2515 xlog_verify_dest_ptr(log, ptr); 2516 2517 /* 2518 * Copy region. 2519 * 2520 * Unmount records just log an opheader, so can have 2521 * empty payloads with no data region to copy. Hence we 2522 * only copy the payload if the vector says it has data 2523 * to copy. 2524 */ 2525 ASSERT(copy_len >= 0); 2526 if (copy_len > 0) { 2527 memcpy(ptr, reg->i_addr + copy_off, copy_len); 2528 xlog_write_adv_cnt(&ptr, &len, &log_offset, 2529 copy_len); 2530 } 2531 copy_len += start_rec_copy + sizeof(xlog_op_header_t); 2532 record_cnt++; 2533 data_cnt += contwr ? copy_len : 0; 2534 2535 error = xlog_write_copy_finish(log, iclog, flags, 2536 &record_cnt, &data_cnt, 2537 &partial_copy, 2538 &partial_copy_len, 2539 log_offset, 2540 commit_iclog); 2541 if (error) 2542 return error; 2543 2544 /* 2545 * if we had a partial copy, we need to get more iclog 2546 * space but we don't want to increment the region 2547 * index because there is still more is this region to 2548 * write. 2549 * 2550 * If we completed writing this region, and we flushed 2551 * the iclog (indicated by resetting of the record 2552 * count), then we also need to get more log space. If 2553 * this was the last record, though, we are done and 2554 * can just return. 2555 */ 2556 if (partial_copy) 2557 break; 2558 2559 if (++index == lv->lv_niovecs) { 2560 next_lv: 2561 lv = lv->lv_next; 2562 index = 0; 2563 if (lv) 2564 vecp = lv->lv_iovecp; 2565 } 2566 if (record_cnt == 0 && !ordered) { 2567 if (!lv) 2568 return 0; 2569 break; 2570 } 2571 } 2572 } 2573 2574 ASSERT(len == 0); 2575 2576 xlog_state_finish_copy(log, iclog, record_cnt, data_cnt); 2577 if (!commit_iclog) 2578 return xlog_state_release_iclog(log, iclog); 2579 2580 ASSERT(flags & XLOG_COMMIT_TRANS); 2581 *commit_iclog = iclog; 2582 return 0; 2583 } 2584 2585 2586 /***************************************************************************** 2587 * 2588 * State Machine functions 2589 * 2590 ***************************************************************************** 2591 */ 2592 2593 /* Clean iclogs starting from the head. This ordering must be 2594 * maintained, so an iclog doesn't become ACTIVE beyond one that 2595 * is SYNCING. This is also required to maintain the notion that we use 2596 * a ordered wait queue to hold off would be writers to the log when every 2597 * iclog is trying to sync to disk. 2598 * 2599 * State Change: DIRTY -> ACTIVE 2600 */ 2601 STATIC void 2602 xlog_state_clean_log( 2603 struct xlog *log) 2604 { 2605 xlog_in_core_t *iclog; 2606 int changed = 0; 2607 2608 iclog = log->l_iclog; 2609 do { 2610 if (iclog->ic_state == XLOG_STATE_DIRTY) { 2611 iclog->ic_state = XLOG_STATE_ACTIVE; 2612 iclog->ic_offset = 0; 2613 ASSERT(iclog->ic_callback == NULL); 2614 /* 2615 * If the number of ops in this iclog indicate it just 2616 * contains the dummy transaction, we can 2617 * change state into IDLE (the second time around). 2618 * Otherwise we should change the state into 2619 * NEED a dummy. 2620 * We don't need to cover the dummy. 2621 */ 2622 if (!changed && 2623 (be32_to_cpu(iclog->ic_header.h_num_logops) == 2624 XLOG_COVER_OPS)) { 2625 changed = 1; 2626 } else { 2627 /* 2628 * We have two dirty iclogs so start over 2629 * This could also be num of ops indicates 2630 * this is not the dummy going out. 2631 */ 2632 changed = 2; 2633 } 2634 iclog->ic_header.h_num_logops = 0; 2635 memset(iclog->ic_header.h_cycle_data, 0, 2636 sizeof(iclog->ic_header.h_cycle_data)); 2637 iclog->ic_header.h_lsn = 0; 2638 } else if (iclog->ic_state == XLOG_STATE_ACTIVE) 2639 /* do nothing */; 2640 else 2641 break; /* stop cleaning */ 2642 iclog = iclog->ic_next; 2643 } while (iclog != log->l_iclog); 2644 2645 /* log is locked when we are called */ 2646 /* 2647 * Change state for the dummy log recording. 2648 * We usually go to NEED. But we go to NEED2 if the changed indicates 2649 * we are done writing the dummy record. 2650 * If we are done with the second dummy recored (DONE2), then 2651 * we go to IDLE. 2652 */ 2653 if (changed) { 2654 switch (log->l_covered_state) { 2655 case XLOG_STATE_COVER_IDLE: 2656 case XLOG_STATE_COVER_NEED: 2657 case XLOG_STATE_COVER_NEED2: 2658 log->l_covered_state = XLOG_STATE_COVER_NEED; 2659 break; 2660 2661 case XLOG_STATE_COVER_DONE: 2662 if (changed == 1) 2663 log->l_covered_state = XLOG_STATE_COVER_NEED2; 2664 else 2665 log->l_covered_state = XLOG_STATE_COVER_NEED; 2666 break; 2667 2668 case XLOG_STATE_COVER_DONE2: 2669 if (changed == 1) 2670 log->l_covered_state = XLOG_STATE_COVER_IDLE; 2671 else 2672 log->l_covered_state = XLOG_STATE_COVER_NEED; 2673 break; 2674 2675 default: 2676 ASSERT(0); 2677 } 2678 } 2679 } /* xlog_state_clean_log */ 2680 2681 STATIC xfs_lsn_t 2682 xlog_get_lowest_lsn( 2683 struct xlog *log) 2684 { 2685 xlog_in_core_t *lsn_log; 2686 xfs_lsn_t lowest_lsn, lsn; 2687 2688 lsn_log = log->l_iclog; 2689 lowest_lsn = 0; 2690 do { 2691 if (!(lsn_log->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_DIRTY))) { 2692 lsn = be64_to_cpu(lsn_log->ic_header.h_lsn); 2693 if ((lsn && !lowest_lsn) || 2694 (XFS_LSN_CMP(lsn, lowest_lsn) < 0)) { 2695 lowest_lsn = lsn; 2696 } 2697 } 2698 lsn_log = lsn_log->ic_next; 2699 } while (lsn_log != log->l_iclog); 2700 return lowest_lsn; 2701 } 2702 2703 2704 STATIC void 2705 xlog_state_do_callback( 2706 struct xlog *log, 2707 int aborted, 2708 struct xlog_in_core *ciclog) 2709 { 2710 xlog_in_core_t *iclog; 2711 xlog_in_core_t *first_iclog; /* used to know when we've 2712 * processed all iclogs once */ 2713 xfs_log_callback_t *cb, *cb_next; 2714 int flushcnt = 0; 2715 xfs_lsn_t lowest_lsn; 2716 int ioerrors; /* counter: iclogs with errors */ 2717 int loopdidcallbacks; /* flag: inner loop did callbacks*/ 2718 int funcdidcallbacks; /* flag: function did callbacks */ 2719 int repeats; /* for issuing console warnings if 2720 * looping too many times */ 2721 int wake = 0; 2722 2723 spin_lock(&log->l_icloglock); 2724 first_iclog = iclog = log->l_iclog; 2725 ioerrors = 0; 2726 funcdidcallbacks = 0; 2727 repeats = 0; 2728 2729 do { 2730 /* 2731 * Scan all iclogs starting with the one pointed to by the 2732 * log. Reset this starting point each time the log is 2733 * unlocked (during callbacks). 2734 * 2735 * Keep looping through iclogs until one full pass is made 2736 * without running any callbacks. 2737 */ 2738 first_iclog = log->l_iclog; 2739 iclog = log->l_iclog; 2740 loopdidcallbacks = 0; 2741 repeats++; 2742 2743 do { 2744 2745 /* skip all iclogs in the ACTIVE & DIRTY states */ 2746 if (iclog->ic_state & 2747 (XLOG_STATE_ACTIVE|XLOG_STATE_DIRTY)) { 2748 iclog = iclog->ic_next; 2749 continue; 2750 } 2751 2752 /* 2753 * Between marking a filesystem SHUTDOWN and stopping 2754 * the log, we do flush all iclogs to disk (if there 2755 * wasn't a log I/O error). So, we do want things to 2756 * go smoothly in case of just a SHUTDOWN w/o a 2757 * LOG_IO_ERROR. 2758 */ 2759 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) { 2760 /* 2761 * Can only perform callbacks in order. Since 2762 * this iclog is not in the DONE_SYNC/ 2763 * DO_CALLBACK state, we skip the rest and 2764 * just try to clean up. If we set our iclog 2765 * to DO_CALLBACK, we will not process it when 2766 * we retry since a previous iclog is in the 2767 * CALLBACK and the state cannot change since 2768 * we are holding the l_icloglock. 2769 */ 2770 if (!(iclog->ic_state & 2771 (XLOG_STATE_DONE_SYNC | 2772 XLOG_STATE_DO_CALLBACK))) { 2773 if (ciclog && (ciclog->ic_state == 2774 XLOG_STATE_DONE_SYNC)) { 2775 ciclog->ic_state = XLOG_STATE_DO_CALLBACK; 2776 } 2777 break; 2778 } 2779 /* 2780 * We now have an iclog that is in either the 2781 * DO_CALLBACK or DONE_SYNC states. The other 2782 * states (WANT_SYNC, SYNCING, or CALLBACK were 2783 * caught by the above if and are going to 2784 * clean (i.e. we aren't doing their callbacks) 2785 * see the above if. 2786 */ 2787 2788 /* 2789 * We will do one more check here to see if we 2790 * have chased our tail around. 2791 */ 2792 2793 lowest_lsn = xlog_get_lowest_lsn(log); 2794 if (lowest_lsn && 2795 XFS_LSN_CMP(lowest_lsn, 2796 be64_to_cpu(iclog->ic_header.h_lsn)) < 0) { 2797 iclog = iclog->ic_next; 2798 continue; /* Leave this iclog for 2799 * another thread */ 2800 } 2801 2802 iclog->ic_state = XLOG_STATE_CALLBACK; 2803 2804 2805 /* 2806 * Completion of a iclog IO does not imply that 2807 * a transaction has completed, as transactions 2808 * can be large enough to span many iclogs. We 2809 * cannot change the tail of the log half way 2810 * through a transaction as this may be the only 2811 * transaction in the log and moving th etail to 2812 * point to the middle of it will prevent 2813 * recovery from finding the start of the 2814 * transaction. Hence we should only update the 2815 * last_sync_lsn if this iclog contains 2816 * transaction completion callbacks on it. 2817 * 2818 * We have to do this before we drop the 2819 * icloglock to ensure we are the only one that 2820 * can update it. 2821 */ 2822 ASSERT(XFS_LSN_CMP(atomic64_read(&log->l_last_sync_lsn), 2823 be64_to_cpu(iclog->ic_header.h_lsn)) <= 0); 2824 if (iclog->ic_callback) 2825 atomic64_set(&log->l_last_sync_lsn, 2826 be64_to_cpu(iclog->ic_header.h_lsn)); 2827 2828 } else 2829 ioerrors++; 2830 2831 spin_unlock(&log->l_icloglock); 2832 2833 /* 2834 * Keep processing entries in the callback list until 2835 * we come around and it is empty. We need to 2836 * atomically see that the list is empty and change the 2837 * state to DIRTY so that we don't miss any more 2838 * callbacks being added. 2839 */ 2840 spin_lock(&iclog->ic_callback_lock); 2841 cb = iclog->ic_callback; 2842 while (cb) { 2843 iclog->ic_callback_tail = &(iclog->ic_callback); 2844 iclog->ic_callback = NULL; 2845 spin_unlock(&iclog->ic_callback_lock); 2846 2847 /* perform callbacks in the order given */ 2848 for (; cb; cb = cb_next) { 2849 cb_next = cb->cb_next; 2850 cb->cb_func(cb->cb_arg, aborted); 2851 } 2852 spin_lock(&iclog->ic_callback_lock); 2853 cb = iclog->ic_callback; 2854 } 2855 2856 loopdidcallbacks++; 2857 funcdidcallbacks++; 2858 2859 spin_lock(&log->l_icloglock); 2860 ASSERT(iclog->ic_callback == NULL); 2861 spin_unlock(&iclog->ic_callback_lock); 2862 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) 2863 iclog->ic_state = XLOG_STATE_DIRTY; 2864 2865 /* 2866 * Transition from DIRTY to ACTIVE if applicable. 2867 * NOP if STATE_IOERROR. 2868 */ 2869 xlog_state_clean_log(log); 2870 2871 /* wake up threads waiting in xfs_log_force() */ 2872 wake_up_all(&iclog->ic_force_wait); 2873 2874 iclog = iclog->ic_next; 2875 } while (first_iclog != iclog); 2876 2877 if (repeats > 5000) { 2878 flushcnt += repeats; 2879 repeats = 0; 2880 xfs_warn(log->l_mp, 2881 "%s: possible infinite loop (%d iterations)", 2882 __func__, flushcnt); 2883 } 2884 } while (!ioerrors && loopdidcallbacks); 2885 2886 #ifdef DEBUG 2887 /* 2888 * Make one last gasp attempt to see if iclogs are being left in limbo. 2889 * If the above loop finds an iclog earlier than the current iclog and 2890 * in one of the syncing states, the current iclog is put into 2891 * DO_CALLBACK and the callbacks are deferred to the completion of the 2892 * earlier iclog. Walk the iclogs in order and make sure that no iclog 2893 * is in DO_CALLBACK unless an earlier iclog is in one of the syncing 2894 * states. 2895 * 2896 * Note that SYNCING|IOABORT is a valid state so we cannot just check 2897 * for ic_state == SYNCING. 2898 */ 2899 if (funcdidcallbacks) { 2900 first_iclog = iclog = log->l_iclog; 2901 do { 2902 ASSERT(iclog->ic_state != XLOG_STATE_DO_CALLBACK); 2903 /* 2904 * Terminate the loop if iclogs are found in states 2905 * which will cause other threads to clean up iclogs. 2906 * 2907 * SYNCING - i/o completion will go through logs 2908 * DONE_SYNC - interrupt thread should be waiting for 2909 * l_icloglock 2910 * IOERROR - give up hope all ye who enter here 2911 */ 2912 if (iclog->ic_state == XLOG_STATE_WANT_SYNC || 2913 iclog->ic_state & XLOG_STATE_SYNCING || 2914 iclog->ic_state == XLOG_STATE_DONE_SYNC || 2915 iclog->ic_state == XLOG_STATE_IOERROR ) 2916 break; 2917 iclog = iclog->ic_next; 2918 } while (first_iclog != iclog); 2919 } 2920 #endif 2921 2922 if (log->l_iclog->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_IOERROR)) 2923 wake = 1; 2924 spin_unlock(&log->l_icloglock); 2925 2926 if (wake) 2927 wake_up_all(&log->l_flush_wait); 2928 } 2929 2930 2931 /* 2932 * Finish transitioning this iclog to the dirty state. 2933 * 2934 * Make sure that we completely execute this routine only when this is 2935 * the last call to the iclog. There is a good chance that iclog flushes, 2936 * when we reach the end of the physical log, get turned into 2 separate 2937 * calls to bwrite. Hence, one iclog flush could generate two calls to this 2938 * routine. By using the reference count bwritecnt, we guarantee that only 2939 * the second completion goes through. 2940 * 2941 * Callbacks could take time, so they are done outside the scope of the 2942 * global state machine log lock. 2943 */ 2944 STATIC void 2945 xlog_state_done_syncing( 2946 xlog_in_core_t *iclog, 2947 int aborted) 2948 { 2949 struct xlog *log = iclog->ic_log; 2950 2951 spin_lock(&log->l_icloglock); 2952 2953 ASSERT(iclog->ic_state == XLOG_STATE_SYNCING || 2954 iclog->ic_state == XLOG_STATE_IOERROR); 2955 ASSERT(atomic_read(&iclog->ic_refcnt) == 0); 2956 ASSERT(iclog->ic_bwritecnt == 1 || iclog->ic_bwritecnt == 2); 2957 2958 2959 /* 2960 * If we got an error, either on the first buffer, or in the case of 2961 * split log writes, on the second, we mark ALL iclogs STATE_IOERROR, 2962 * and none should ever be attempted to be written to disk 2963 * again. 2964 */ 2965 if (iclog->ic_state != XLOG_STATE_IOERROR) { 2966 if (--iclog->ic_bwritecnt == 1) { 2967 spin_unlock(&log->l_icloglock); 2968 return; 2969 } 2970 iclog->ic_state = XLOG_STATE_DONE_SYNC; 2971 } 2972 2973 /* 2974 * Someone could be sleeping prior to writing out the next 2975 * iclog buffer, we wake them all, one will get to do the 2976 * I/O, the others get to wait for the result. 2977 */ 2978 wake_up_all(&iclog->ic_write_wait); 2979 spin_unlock(&log->l_icloglock); 2980 xlog_state_do_callback(log, aborted, iclog); /* also cleans log */ 2981 } /* xlog_state_done_syncing */ 2982 2983 2984 /* 2985 * If the head of the in-core log ring is not (ACTIVE or DIRTY), then we must 2986 * sleep. We wait on the flush queue on the head iclog as that should be 2987 * the first iclog to complete flushing. Hence if all iclogs are syncing, 2988 * we will wait here and all new writes will sleep until a sync completes. 2989 * 2990 * The in-core logs are used in a circular fashion. They are not used 2991 * out-of-order even when an iclog past the head is free. 2992 * 2993 * return: 2994 * * log_offset where xlog_write() can start writing into the in-core 2995 * log's data space. 2996 * * in-core log pointer to which xlog_write() should write. 2997 * * boolean indicating this is a continued write to an in-core log. 2998 * If this is the last write, then the in-core log's offset field 2999 * needs to be incremented, depending on the amount of data which 3000 * is copied. 3001 */ 3002 STATIC int 3003 xlog_state_get_iclog_space( 3004 struct xlog *log, 3005 int len, 3006 struct xlog_in_core **iclogp, 3007 struct xlog_ticket *ticket, 3008 int *continued_write, 3009 int *logoffsetp) 3010 { 3011 int log_offset; 3012 xlog_rec_header_t *head; 3013 xlog_in_core_t *iclog; 3014 int error; 3015 3016 restart: 3017 spin_lock(&log->l_icloglock); 3018 if (XLOG_FORCED_SHUTDOWN(log)) { 3019 spin_unlock(&log->l_icloglock); 3020 return -EIO; 3021 } 3022 3023 iclog = log->l_iclog; 3024 if (iclog->ic_state != XLOG_STATE_ACTIVE) { 3025 XFS_STATS_INC(log->l_mp, xs_log_noiclogs); 3026 3027 /* Wait for log writes to have flushed */ 3028 xlog_wait(&log->l_flush_wait, &log->l_icloglock); 3029 goto restart; 3030 } 3031 3032 head = &iclog->ic_header; 3033 3034 atomic_inc(&iclog->ic_refcnt); /* prevents sync */ 3035 log_offset = iclog->ic_offset; 3036 3037 /* On the 1st write to an iclog, figure out lsn. This works 3038 * if iclogs marked XLOG_STATE_WANT_SYNC always write out what they are 3039 * committing to. If the offset is set, that's how many blocks 3040 * must be written. 3041 */ 3042 if (log_offset == 0) { 3043 ticket->t_curr_res -= log->l_iclog_hsize; 3044 xlog_tic_add_region(ticket, 3045 log->l_iclog_hsize, 3046 XLOG_REG_TYPE_LRHEADER); 3047 head->h_cycle = cpu_to_be32(log->l_curr_cycle); 3048 head->h_lsn = cpu_to_be64( 3049 xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block)); 3050 ASSERT(log->l_curr_block >= 0); 3051 } 3052 3053 /* If there is enough room to write everything, then do it. Otherwise, 3054 * claim the rest of the region and make sure the XLOG_STATE_WANT_SYNC 3055 * bit is on, so this will get flushed out. Don't update ic_offset 3056 * until you know exactly how many bytes get copied. Therefore, wait 3057 * until later to update ic_offset. 3058 * 3059 * xlog_write() algorithm assumes that at least 2 xlog_op_header_t's 3060 * can fit into remaining data section. 3061 */ 3062 if (iclog->ic_size - iclog->ic_offset < 2*sizeof(xlog_op_header_t)) { 3063 xlog_state_switch_iclogs(log, iclog, iclog->ic_size); 3064 3065 /* 3066 * If I'm the only one writing to this iclog, sync it to disk. 3067 * We need to do an atomic compare and decrement here to avoid 3068 * racing with concurrent atomic_dec_and_lock() calls in 3069 * xlog_state_release_iclog() when there is more than one 3070 * reference to the iclog. 3071 */ 3072 if (!atomic_add_unless(&iclog->ic_refcnt, -1, 1)) { 3073 /* we are the only one */ 3074 spin_unlock(&log->l_icloglock); 3075 error = xlog_state_release_iclog(log, iclog); 3076 if (error) 3077 return error; 3078 } else { 3079 spin_unlock(&log->l_icloglock); 3080 } 3081 goto restart; 3082 } 3083 3084 /* Do we have enough room to write the full amount in the remainder 3085 * of this iclog? Or must we continue a write on the next iclog and 3086 * mark this iclog as completely taken? In the case where we switch 3087 * iclogs (to mark it taken), this particular iclog will release/sync 3088 * to disk in xlog_write(). 3089 */ 3090 if (len <= iclog->ic_size - iclog->ic_offset) { 3091 *continued_write = 0; 3092 iclog->ic_offset += len; 3093 } else { 3094 *continued_write = 1; 3095 xlog_state_switch_iclogs(log, iclog, iclog->ic_size); 3096 } 3097 *iclogp = iclog; 3098 3099 ASSERT(iclog->ic_offset <= iclog->ic_size); 3100 spin_unlock(&log->l_icloglock); 3101 3102 *logoffsetp = log_offset; 3103 return 0; 3104 } /* xlog_state_get_iclog_space */ 3105 3106 /* The first cnt-1 times through here we don't need to 3107 * move the grant write head because the permanent 3108 * reservation has reserved cnt times the unit amount. 3109 * Release part of current permanent unit reservation and 3110 * reset current reservation to be one units worth. Also 3111 * move grant reservation head forward. 3112 */ 3113 STATIC void 3114 xlog_regrant_reserve_log_space( 3115 struct xlog *log, 3116 struct xlog_ticket *ticket) 3117 { 3118 trace_xfs_log_regrant_reserve_enter(log, ticket); 3119 3120 if (ticket->t_cnt > 0) 3121 ticket->t_cnt--; 3122 3123 xlog_grant_sub_space(log, &log->l_reserve_head.grant, 3124 ticket->t_curr_res); 3125 xlog_grant_sub_space(log, &log->l_write_head.grant, 3126 ticket->t_curr_res); 3127 ticket->t_curr_res = ticket->t_unit_res; 3128 xlog_tic_reset_res(ticket); 3129 3130 trace_xfs_log_regrant_reserve_sub(log, ticket); 3131 3132 /* just return if we still have some of the pre-reserved space */ 3133 if (ticket->t_cnt > 0) 3134 return; 3135 3136 xlog_grant_add_space(log, &log->l_reserve_head.grant, 3137 ticket->t_unit_res); 3138 3139 trace_xfs_log_regrant_reserve_exit(log, ticket); 3140 3141 ticket->t_curr_res = ticket->t_unit_res; 3142 xlog_tic_reset_res(ticket); 3143 } /* xlog_regrant_reserve_log_space */ 3144 3145 3146 /* 3147 * Give back the space left from a reservation. 3148 * 3149 * All the information we need to make a correct determination of space left 3150 * is present. For non-permanent reservations, things are quite easy. The 3151 * count should have been decremented to zero. We only need to deal with the 3152 * space remaining in the current reservation part of the ticket. If the 3153 * ticket contains a permanent reservation, there may be left over space which 3154 * needs to be released. A count of N means that N-1 refills of the current 3155 * reservation can be done before we need to ask for more space. The first 3156 * one goes to fill up the first current reservation. Once we run out of 3157 * space, the count will stay at zero and the only space remaining will be 3158 * in the current reservation field. 3159 */ 3160 STATIC void 3161 xlog_ungrant_log_space( 3162 struct xlog *log, 3163 struct xlog_ticket *ticket) 3164 { 3165 int bytes; 3166 3167 if (ticket->t_cnt > 0) 3168 ticket->t_cnt--; 3169 3170 trace_xfs_log_ungrant_enter(log, ticket); 3171 trace_xfs_log_ungrant_sub(log, ticket); 3172 3173 /* 3174 * If this is a permanent reservation ticket, we may be able to free 3175 * up more space based on the remaining count. 3176 */ 3177 bytes = ticket->t_curr_res; 3178 if (ticket->t_cnt > 0) { 3179 ASSERT(ticket->t_flags & XLOG_TIC_PERM_RESERV); 3180 bytes += ticket->t_unit_res*ticket->t_cnt; 3181 } 3182 3183 xlog_grant_sub_space(log, &log->l_reserve_head.grant, bytes); 3184 xlog_grant_sub_space(log, &log->l_write_head.grant, bytes); 3185 3186 trace_xfs_log_ungrant_exit(log, ticket); 3187 3188 xfs_log_space_wake(log->l_mp); 3189 } 3190 3191 /* 3192 * Flush iclog to disk if this is the last reference to the given iclog and 3193 * the WANT_SYNC bit is set. 3194 * 3195 * When this function is entered, the iclog is not necessarily in the 3196 * WANT_SYNC state. It may be sitting around waiting to get filled. 3197 * 3198 * 3199 */ 3200 STATIC int 3201 xlog_state_release_iclog( 3202 struct xlog *log, 3203 struct xlog_in_core *iclog) 3204 { 3205 int sync = 0; /* do we sync? */ 3206 3207 if (iclog->ic_state & XLOG_STATE_IOERROR) 3208 return -EIO; 3209 3210 ASSERT(atomic_read(&iclog->ic_refcnt) > 0); 3211 if (!atomic_dec_and_lock(&iclog->ic_refcnt, &log->l_icloglock)) 3212 return 0; 3213 3214 if (iclog->ic_state & XLOG_STATE_IOERROR) { 3215 spin_unlock(&log->l_icloglock); 3216 return -EIO; 3217 } 3218 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE || 3219 iclog->ic_state == XLOG_STATE_WANT_SYNC); 3220 3221 if (iclog->ic_state == XLOG_STATE_WANT_SYNC) { 3222 /* update tail before writing to iclog */ 3223 xfs_lsn_t tail_lsn = xlog_assign_tail_lsn(log->l_mp); 3224 sync++; 3225 iclog->ic_state = XLOG_STATE_SYNCING; 3226 iclog->ic_header.h_tail_lsn = cpu_to_be64(tail_lsn); 3227 xlog_verify_tail_lsn(log, iclog, tail_lsn); 3228 /* cycle incremented when incrementing curr_block */ 3229 } 3230 spin_unlock(&log->l_icloglock); 3231 3232 /* 3233 * We let the log lock go, so it's possible that we hit a log I/O 3234 * error or some other SHUTDOWN condition that marks the iclog 3235 * as XLOG_STATE_IOERROR before the bwrite. However, we know that 3236 * this iclog has consistent data, so we ignore IOERROR 3237 * flags after this point. 3238 */ 3239 if (sync) 3240 return xlog_sync(log, iclog); 3241 return 0; 3242 } /* xlog_state_release_iclog */ 3243 3244 3245 /* 3246 * This routine will mark the current iclog in the ring as WANT_SYNC 3247 * and move the current iclog pointer to the next iclog in the ring. 3248 * When this routine is called from xlog_state_get_iclog_space(), the 3249 * exact size of the iclog has not yet been determined. All we know is 3250 * that every data block. We have run out of space in this log record. 3251 */ 3252 STATIC void 3253 xlog_state_switch_iclogs( 3254 struct xlog *log, 3255 struct xlog_in_core *iclog, 3256 int eventual_size) 3257 { 3258 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE); 3259 if (!eventual_size) 3260 eventual_size = iclog->ic_offset; 3261 iclog->ic_state = XLOG_STATE_WANT_SYNC; 3262 iclog->ic_header.h_prev_block = cpu_to_be32(log->l_prev_block); 3263 log->l_prev_block = log->l_curr_block; 3264 log->l_prev_cycle = log->l_curr_cycle; 3265 3266 /* roll log?: ic_offset changed later */ 3267 log->l_curr_block += BTOBB(eventual_size)+BTOBB(log->l_iclog_hsize); 3268 3269 /* Round up to next log-sunit */ 3270 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb) && 3271 log->l_mp->m_sb.sb_logsunit > 1) { 3272 uint32_t sunit_bb = BTOBB(log->l_mp->m_sb.sb_logsunit); 3273 log->l_curr_block = roundup(log->l_curr_block, sunit_bb); 3274 } 3275 3276 if (log->l_curr_block >= log->l_logBBsize) { 3277 /* 3278 * Rewind the current block before the cycle is bumped to make 3279 * sure that the combined LSN never transiently moves forward 3280 * when the log wraps to the next cycle. This is to support the 3281 * unlocked sample of these fields from xlog_valid_lsn(). Most 3282 * other cases should acquire l_icloglock. 3283 */ 3284 log->l_curr_block -= log->l_logBBsize; 3285 ASSERT(log->l_curr_block >= 0); 3286 smp_wmb(); 3287 log->l_curr_cycle++; 3288 if (log->l_curr_cycle == XLOG_HEADER_MAGIC_NUM) 3289 log->l_curr_cycle++; 3290 } 3291 ASSERT(iclog == log->l_iclog); 3292 log->l_iclog = iclog->ic_next; 3293 } /* xlog_state_switch_iclogs */ 3294 3295 /* 3296 * Write out all data in the in-core log as of this exact moment in time. 3297 * 3298 * Data may be written to the in-core log during this call. However, 3299 * we don't guarantee this data will be written out. A change from past 3300 * implementation means this routine will *not* write out zero length LRs. 3301 * 3302 * Basically, we try and perform an intelligent scan of the in-core logs. 3303 * If we determine there is no flushable data, we just return. There is no 3304 * flushable data if: 3305 * 3306 * 1. the current iclog is active and has no data; the previous iclog 3307 * is in the active or dirty state. 3308 * 2. the current iclog is drity, and the previous iclog is in the 3309 * active or dirty state. 3310 * 3311 * We may sleep if: 3312 * 3313 * 1. the current iclog is not in the active nor dirty state. 3314 * 2. the current iclog dirty, and the previous iclog is not in the 3315 * active nor dirty state. 3316 * 3. the current iclog is active, and there is another thread writing 3317 * to this particular iclog. 3318 * 4. a) the current iclog is active and has no other writers 3319 * b) when we return from flushing out this iclog, it is still 3320 * not in the active nor dirty state. 3321 */ 3322 int 3323 xfs_log_force( 3324 struct xfs_mount *mp, 3325 uint flags) 3326 { 3327 struct xlog *log = mp->m_log; 3328 struct xlog_in_core *iclog; 3329 xfs_lsn_t lsn; 3330 3331 XFS_STATS_INC(mp, xs_log_force); 3332 trace_xfs_log_force(mp, 0, _RET_IP_); 3333 3334 xlog_cil_force(log); 3335 3336 spin_lock(&log->l_icloglock); 3337 iclog = log->l_iclog; 3338 if (iclog->ic_state & XLOG_STATE_IOERROR) 3339 goto out_error; 3340 3341 if (iclog->ic_state == XLOG_STATE_DIRTY || 3342 (iclog->ic_state == XLOG_STATE_ACTIVE && 3343 atomic_read(&iclog->ic_refcnt) == 0 && iclog->ic_offset == 0)) { 3344 /* 3345 * If the head is dirty or (active and empty), then we need to 3346 * look at the previous iclog. 3347 * 3348 * If the previous iclog is active or dirty we are done. There 3349 * is nothing to sync out. Otherwise, we attach ourselves to the 3350 * previous iclog and go to sleep. 3351 */ 3352 iclog = iclog->ic_prev; 3353 if (iclog->ic_state == XLOG_STATE_ACTIVE || 3354 iclog->ic_state == XLOG_STATE_DIRTY) 3355 goto out_unlock; 3356 } else if (iclog->ic_state == XLOG_STATE_ACTIVE) { 3357 if (atomic_read(&iclog->ic_refcnt) == 0) { 3358 /* 3359 * We are the only one with access to this iclog. 3360 * 3361 * Flush it out now. There should be a roundoff of zero 3362 * to show that someone has already taken care of the 3363 * roundoff from the previous sync. 3364 */ 3365 atomic_inc(&iclog->ic_refcnt); 3366 lsn = be64_to_cpu(iclog->ic_header.h_lsn); 3367 xlog_state_switch_iclogs(log, iclog, 0); 3368 spin_unlock(&log->l_icloglock); 3369 3370 if (xlog_state_release_iclog(log, iclog)) 3371 return -EIO; 3372 3373 spin_lock(&log->l_icloglock); 3374 if (be64_to_cpu(iclog->ic_header.h_lsn) != lsn || 3375 iclog->ic_state == XLOG_STATE_DIRTY) 3376 goto out_unlock; 3377 } else { 3378 /* 3379 * Someone else is writing to this iclog. 3380 * 3381 * Use its call to flush out the data. However, the 3382 * other thread may not force out this LR, so we mark 3383 * it WANT_SYNC. 3384 */ 3385 xlog_state_switch_iclogs(log, iclog, 0); 3386 } 3387 } else { 3388 /* 3389 * If the head iclog is not active nor dirty, we just attach 3390 * ourselves to the head and go to sleep if necessary. 3391 */ 3392 ; 3393 } 3394 3395 if (!(flags & XFS_LOG_SYNC)) 3396 goto out_unlock; 3397 3398 if (iclog->ic_state & XLOG_STATE_IOERROR) 3399 goto out_error; 3400 XFS_STATS_INC(mp, xs_log_force_sleep); 3401 xlog_wait(&iclog->ic_force_wait, &log->l_icloglock); 3402 if (iclog->ic_state & XLOG_STATE_IOERROR) 3403 return -EIO; 3404 return 0; 3405 3406 out_unlock: 3407 spin_unlock(&log->l_icloglock); 3408 return 0; 3409 out_error: 3410 spin_unlock(&log->l_icloglock); 3411 return -EIO; 3412 } 3413 3414 static int 3415 __xfs_log_force_lsn( 3416 struct xfs_mount *mp, 3417 xfs_lsn_t lsn, 3418 uint flags, 3419 int *log_flushed, 3420 bool already_slept) 3421 { 3422 struct xlog *log = mp->m_log; 3423 struct xlog_in_core *iclog; 3424 3425 spin_lock(&log->l_icloglock); 3426 iclog = log->l_iclog; 3427 if (iclog->ic_state & XLOG_STATE_IOERROR) 3428 goto out_error; 3429 3430 while (be64_to_cpu(iclog->ic_header.h_lsn) != lsn) { 3431 iclog = iclog->ic_next; 3432 if (iclog == log->l_iclog) 3433 goto out_unlock; 3434 } 3435 3436 if (iclog->ic_state == XLOG_STATE_DIRTY) 3437 goto out_unlock; 3438 3439 if (iclog->ic_state == XLOG_STATE_ACTIVE) { 3440 /* 3441 * We sleep here if we haven't already slept (e.g. this is the 3442 * first time we've looked at the correct iclog buf) and the 3443 * buffer before us is going to be sync'ed. The reason for this 3444 * is that if we are doing sync transactions here, by waiting 3445 * for the previous I/O to complete, we can allow a few more 3446 * transactions into this iclog before we close it down. 3447 * 3448 * Otherwise, we mark the buffer WANT_SYNC, and bump up the 3449 * refcnt so we can release the log (which drops the ref count). 3450 * The state switch keeps new transaction commits from using 3451 * this buffer. When the current commits finish writing into 3452 * the buffer, the refcount will drop to zero and the buffer 3453 * will go out then. 3454 */ 3455 if (!already_slept && 3456 (iclog->ic_prev->ic_state & 3457 (XLOG_STATE_WANT_SYNC | XLOG_STATE_SYNCING))) { 3458 ASSERT(!(iclog->ic_state & XLOG_STATE_IOERROR)); 3459 3460 XFS_STATS_INC(mp, xs_log_force_sleep); 3461 3462 xlog_wait(&iclog->ic_prev->ic_write_wait, 3463 &log->l_icloglock); 3464 return -EAGAIN; 3465 } 3466 atomic_inc(&iclog->ic_refcnt); 3467 xlog_state_switch_iclogs(log, iclog, 0); 3468 spin_unlock(&log->l_icloglock); 3469 if (xlog_state_release_iclog(log, iclog)) 3470 return -EIO; 3471 if (log_flushed) 3472 *log_flushed = 1; 3473 spin_lock(&log->l_icloglock); 3474 } 3475 3476 if (!(flags & XFS_LOG_SYNC) || 3477 (iclog->ic_state & (XLOG_STATE_ACTIVE | XLOG_STATE_DIRTY))) 3478 goto out_unlock; 3479 3480 if (iclog->ic_state & XLOG_STATE_IOERROR) 3481 goto out_error; 3482 3483 XFS_STATS_INC(mp, xs_log_force_sleep); 3484 xlog_wait(&iclog->ic_force_wait, &log->l_icloglock); 3485 if (iclog->ic_state & XLOG_STATE_IOERROR) 3486 return -EIO; 3487 return 0; 3488 3489 out_unlock: 3490 spin_unlock(&log->l_icloglock); 3491 return 0; 3492 out_error: 3493 spin_unlock(&log->l_icloglock); 3494 return -EIO; 3495 } 3496 3497 /* 3498 * Force the in-core log to disk for a specific LSN. 3499 * 3500 * Find in-core log with lsn. 3501 * If it is in the DIRTY state, just return. 3502 * If it is in the ACTIVE state, move the in-core log into the WANT_SYNC 3503 * state and go to sleep or return. 3504 * If it is in any other state, go to sleep or return. 3505 * 3506 * Synchronous forces are implemented with a wait queue. All callers trying 3507 * to force a given lsn to disk must wait on the queue attached to the 3508 * specific in-core log. When given in-core log finally completes its write 3509 * to disk, that thread will wake up all threads waiting on the queue. 3510 */ 3511 int 3512 xfs_log_force_lsn( 3513 struct xfs_mount *mp, 3514 xfs_lsn_t lsn, 3515 uint flags, 3516 int *log_flushed) 3517 { 3518 int ret; 3519 ASSERT(lsn != 0); 3520 3521 XFS_STATS_INC(mp, xs_log_force); 3522 trace_xfs_log_force(mp, lsn, _RET_IP_); 3523 3524 lsn = xlog_cil_force_lsn(mp->m_log, lsn); 3525 if (lsn == NULLCOMMITLSN) 3526 return 0; 3527 3528 ret = __xfs_log_force_lsn(mp, lsn, flags, log_flushed, false); 3529 if (ret == -EAGAIN) 3530 ret = __xfs_log_force_lsn(mp, lsn, flags, log_flushed, true); 3531 return ret; 3532 } 3533 3534 /* 3535 * Called when we want to mark the current iclog as being ready to sync to 3536 * disk. 3537 */ 3538 STATIC void 3539 xlog_state_want_sync( 3540 struct xlog *log, 3541 struct xlog_in_core *iclog) 3542 { 3543 assert_spin_locked(&log->l_icloglock); 3544 3545 if (iclog->ic_state == XLOG_STATE_ACTIVE) { 3546 xlog_state_switch_iclogs(log, iclog, 0); 3547 } else { 3548 ASSERT(iclog->ic_state & 3549 (XLOG_STATE_WANT_SYNC|XLOG_STATE_IOERROR)); 3550 } 3551 } 3552 3553 3554 /***************************************************************************** 3555 * 3556 * TICKET functions 3557 * 3558 ***************************************************************************** 3559 */ 3560 3561 /* 3562 * Free a used ticket when its refcount falls to zero. 3563 */ 3564 void 3565 xfs_log_ticket_put( 3566 xlog_ticket_t *ticket) 3567 { 3568 ASSERT(atomic_read(&ticket->t_ref) > 0); 3569 if (atomic_dec_and_test(&ticket->t_ref)) 3570 kmem_zone_free(xfs_log_ticket_zone, ticket); 3571 } 3572 3573 xlog_ticket_t * 3574 xfs_log_ticket_get( 3575 xlog_ticket_t *ticket) 3576 { 3577 ASSERT(atomic_read(&ticket->t_ref) > 0); 3578 atomic_inc(&ticket->t_ref); 3579 return ticket; 3580 } 3581 3582 /* 3583 * Figure out the total log space unit (in bytes) that would be 3584 * required for a log ticket. 3585 */ 3586 int 3587 xfs_log_calc_unit_res( 3588 struct xfs_mount *mp, 3589 int unit_bytes) 3590 { 3591 struct xlog *log = mp->m_log; 3592 int iclog_space; 3593 uint num_headers; 3594 3595 /* 3596 * Permanent reservations have up to 'cnt'-1 active log operations 3597 * in the log. A unit in this case is the amount of space for one 3598 * of these log operations. Normal reservations have a cnt of 1 3599 * and their unit amount is the total amount of space required. 3600 * 3601 * The following lines of code account for non-transaction data 3602 * which occupy space in the on-disk log. 3603 * 3604 * Normal form of a transaction is: 3605 * <oph><trans-hdr><start-oph><reg1-oph><reg1><reg2-oph>...<commit-oph> 3606 * and then there are LR hdrs, split-recs and roundoff at end of syncs. 3607 * 3608 * We need to account for all the leadup data and trailer data 3609 * around the transaction data. 3610 * And then we need to account for the worst case in terms of using 3611 * more space. 3612 * The worst case will happen if: 3613 * - the placement of the transaction happens to be such that the 3614 * roundoff is at its maximum 3615 * - the transaction data is synced before the commit record is synced 3616 * i.e. <transaction-data><roundoff> | <commit-rec><roundoff> 3617 * Therefore the commit record is in its own Log Record. 3618 * This can happen as the commit record is called with its 3619 * own region to xlog_write(). 3620 * This then means that in the worst case, roundoff can happen for 3621 * the commit-rec as well. 3622 * The commit-rec is smaller than padding in this scenario and so it is 3623 * not added separately. 3624 */ 3625 3626 /* for trans header */ 3627 unit_bytes += sizeof(xlog_op_header_t); 3628 unit_bytes += sizeof(xfs_trans_header_t); 3629 3630 /* for start-rec */ 3631 unit_bytes += sizeof(xlog_op_header_t); 3632 3633 /* 3634 * for LR headers - the space for data in an iclog is the size minus 3635 * the space used for the headers. If we use the iclog size, then we 3636 * undercalculate the number of headers required. 3637 * 3638 * Furthermore - the addition of op headers for split-recs might 3639 * increase the space required enough to require more log and op 3640 * headers, so take that into account too. 3641 * 3642 * IMPORTANT: This reservation makes the assumption that if this 3643 * transaction is the first in an iclog and hence has the LR headers 3644 * accounted to it, then the remaining space in the iclog is 3645 * exclusively for this transaction. i.e. if the transaction is larger 3646 * than the iclog, it will be the only thing in that iclog. 3647 * Fundamentally, this means we must pass the entire log vector to 3648 * xlog_write to guarantee this. 3649 */ 3650 iclog_space = log->l_iclog_size - log->l_iclog_hsize; 3651 num_headers = howmany(unit_bytes, iclog_space); 3652 3653 /* for split-recs - ophdrs added when data split over LRs */ 3654 unit_bytes += sizeof(xlog_op_header_t) * num_headers; 3655 3656 /* add extra header reservations if we overrun */ 3657 while (!num_headers || 3658 howmany(unit_bytes, iclog_space) > num_headers) { 3659 unit_bytes += sizeof(xlog_op_header_t); 3660 num_headers++; 3661 } 3662 unit_bytes += log->l_iclog_hsize * num_headers; 3663 3664 /* for commit-rec LR header - note: padding will subsume the ophdr */ 3665 unit_bytes += log->l_iclog_hsize; 3666 3667 /* for roundoff padding for transaction data and one for commit record */ 3668 if (xfs_sb_version_haslogv2(&mp->m_sb) && mp->m_sb.sb_logsunit > 1) { 3669 /* log su roundoff */ 3670 unit_bytes += 2 * mp->m_sb.sb_logsunit; 3671 } else { 3672 /* BB roundoff */ 3673 unit_bytes += 2 * BBSIZE; 3674 } 3675 3676 return unit_bytes; 3677 } 3678 3679 /* 3680 * Allocate and initialise a new log ticket. 3681 */ 3682 struct xlog_ticket * 3683 xlog_ticket_alloc( 3684 struct xlog *log, 3685 int unit_bytes, 3686 int cnt, 3687 char client, 3688 bool permanent, 3689 xfs_km_flags_t alloc_flags) 3690 { 3691 struct xlog_ticket *tic; 3692 int unit_res; 3693 3694 tic = kmem_zone_zalloc(xfs_log_ticket_zone, alloc_flags); 3695 if (!tic) 3696 return NULL; 3697 3698 unit_res = xfs_log_calc_unit_res(log->l_mp, unit_bytes); 3699 3700 atomic_set(&tic->t_ref, 1); 3701 tic->t_task = current; 3702 INIT_LIST_HEAD(&tic->t_queue); 3703 tic->t_unit_res = unit_res; 3704 tic->t_curr_res = unit_res; 3705 tic->t_cnt = cnt; 3706 tic->t_ocnt = cnt; 3707 tic->t_tid = prandom_u32(); 3708 tic->t_clientid = client; 3709 tic->t_flags = XLOG_TIC_INITED; 3710 if (permanent) 3711 tic->t_flags |= XLOG_TIC_PERM_RESERV; 3712 3713 xlog_tic_reset_res(tic); 3714 3715 return tic; 3716 } 3717 3718 3719 /****************************************************************************** 3720 * 3721 * Log debug routines 3722 * 3723 ****************************************************************************** 3724 */ 3725 #if defined(DEBUG) 3726 /* 3727 * Make sure that the destination ptr is within the valid data region of 3728 * one of the iclogs. This uses backup pointers stored in a different 3729 * part of the log in case we trash the log structure. 3730 */ 3731 STATIC void 3732 xlog_verify_dest_ptr( 3733 struct xlog *log, 3734 void *ptr) 3735 { 3736 int i; 3737 int good_ptr = 0; 3738 3739 for (i = 0; i < log->l_iclog_bufs; i++) { 3740 if (ptr >= log->l_iclog_bak[i] && 3741 ptr <= log->l_iclog_bak[i] + log->l_iclog_size) 3742 good_ptr++; 3743 } 3744 3745 if (!good_ptr) 3746 xfs_emerg(log->l_mp, "%s: invalid ptr", __func__); 3747 } 3748 3749 /* 3750 * Check to make sure the grant write head didn't just over lap the tail. If 3751 * the cycles are the same, we can't be overlapping. Otherwise, make sure that 3752 * the cycles differ by exactly one and check the byte count. 3753 * 3754 * This check is run unlocked, so can give false positives. Rather than assert 3755 * on failures, use a warn-once flag and a panic tag to allow the admin to 3756 * determine if they want to panic the machine when such an error occurs. For 3757 * debug kernels this will have the same effect as using an assert but, unlinke 3758 * an assert, it can be turned off at runtime. 3759 */ 3760 STATIC void 3761 xlog_verify_grant_tail( 3762 struct xlog *log) 3763 { 3764 int tail_cycle, tail_blocks; 3765 int cycle, space; 3766 3767 xlog_crack_grant_head(&log->l_write_head.grant, &cycle, &space); 3768 xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_blocks); 3769 if (tail_cycle != cycle) { 3770 if (cycle - 1 != tail_cycle && 3771 !(log->l_flags & XLOG_TAIL_WARN)) { 3772 xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES, 3773 "%s: cycle - 1 != tail_cycle", __func__); 3774 log->l_flags |= XLOG_TAIL_WARN; 3775 } 3776 3777 if (space > BBTOB(tail_blocks) && 3778 !(log->l_flags & XLOG_TAIL_WARN)) { 3779 xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES, 3780 "%s: space > BBTOB(tail_blocks)", __func__); 3781 log->l_flags |= XLOG_TAIL_WARN; 3782 } 3783 } 3784 } 3785 3786 /* check if it will fit */ 3787 STATIC void 3788 xlog_verify_tail_lsn( 3789 struct xlog *log, 3790 struct xlog_in_core *iclog, 3791 xfs_lsn_t tail_lsn) 3792 { 3793 int blocks; 3794 3795 if (CYCLE_LSN(tail_lsn) == log->l_prev_cycle) { 3796 blocks = 3797 log->l_logBBsize - (log->l_prev_block - BLOCK_LSN(tail_lsn)); 3798 if (blocks < BTOBB(iclog->ic_offset)+BTOBB(log->l_iclog_hsize)) 3799 xfs_emerg(log->l_mp, "%s: ran out of log space", __func__); 3800 } else { 3801 ASSERT(CYCLE_LSN(tail_lsn)+1 == log->l_prev_cycle); 3802 3803 if (BLOCK_LSN(tail_lsn) == log->l_prev_block) 3804 xfs_emerg(log->l_mp, "%s: tail wrapped", __func__); 3805 3806 blocks = BLOCK_LSN(tail_lsn) - log->l_prev_block; 3807 if (blocks < BTOBB(iclog->ic_offset) + 1) 3808 xfs_emerg(log->l_mp, "%s: ran out of log space", __func__); 3809 } 3810 } /* xlog_verify_tail_lsn */ 3811 3812 /* 3813 * Perform a number of checks on the iclog before writing to disk. 3814 * 3815 * 1. Make sure the iclogs are still circular 3816 * 2. Make sure we have a good magic number 3817 * 3. Make sure we don't have magic numbers in the data 3818 * 4. Check fields of each log operation header for: 3819 * A. Valid client identifier 3820 * B. tid ptr value falls in valid ptr space (user space code) 3821 * C. Length in log record header is correct according to the 3822 * individual operation headers within record. 3823 * 5. When a bwrite will occur within 5 blocks of the front of the physical 3824 * log, check the preceding blocks of the physical log to make sure all 3825 * the cycle numbers agree with the current cycle number. 3826 */ 3827 STATIC void 3828 xlog_verify_iclog( 3829 struct xlog *log, 3830 struct xlog_in_core *iclog, 3831 int count, 3832 bool syncing) 3833 { 3834 xlog_op_header_t *ophead; 3835 xlog_in_core_t *icptr; 3836 xlog_in_core_2_t *xhdr; 3837 void *base_ptr, *ptr, *p; 3838 ptrdiff_t field_offset; 3839 uint8_t clientid; 3840 int len, i, j, k, op_len; 3841 int idx; 3842 3843 /* check validity of iclog pointers */ 3844 spin_lock(&log->l_icloglock); 3845 icptr = log->l_iclog; 3846 for (i = 0; i < log->l_iclog_bufs; i++, icptr = icptr->ic_next) 3847 ASSERT(icptr); 3848 3849 if (icptr != log->l_iclog) 3850 xfs_emerg(log->l_mp, "%s: corrupt iclog ring", __func__); 3851 spin_unlock(&log->l_icloglock); 3852 3853 /* check log magic numbers */ 3854 if (iclog->ic_header.h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) 3855 xfs_emerg(log->l_mp, "%s: invalid magic num", __func__); 3856 3857 base_ptr = ptr = &iclog->ic_header; 3858 p = &iclog->ic_header; 3859 for (ptr += BBSIZE; ptr < base_ptr + count; ptr += BBSIZE) { 3860 if (*(__be32 *)ptr == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) 3861 xfs_emerg(log->l_mp, "%s: unexpected magic num", 3862 __func__); 3863 } 3864 3865 /* check fields */ 3866 len = be32_to_cpu(iclog->ic_header.h_num_logops); 3867 base_ptr = ptr = iclog->ic_datap; 3868 ophead = ptr; 3869 xhdr = iclog->ic_data; 3870 for (i = 0; i < len; i++) { 3871 ophead = ptr; 3872 3873 /* clientid is only 1 byte */ 3874 p = &ophead->oh_clientid; 3875 field_offset = p - base_ptr; 3876 if (!syncing || (field_offset & 0x1ff)) { 3877 clientid = ophead->oh_clientid; 3878 } else { 3879 idx = BTOBBT((char *)&ophead->oh_clientid - iclog->ic_datap); 3880 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) { 3881 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3882 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3883 clientid = xlog_get_client_id( 3884 xhdr[j].hic_xheader.xh_cycle_data[k]); 3885 } else { 3886 clientid = xlog_get_client_id( 3887 iclog->ic_header.h_cycle_data[idx]); 3888 } 3889 } 3890 if (clientid != XFS_TRANSACTION && clientid != XFS_LOG) 3891 xfs_warn(log->l_mp, 3892 "%s: invalid clientid %d op "PTR_FMT" offset 0x%lx", 3893 __func__, clientid, ophead, 3894 (unsigned long)field_offset); 3895 3896 /* check length */ 3897 p = &ophead->oh_len; 3898 field_offset = p - base_ptr; 3899 if (!syncing || (field_offset & 0x1ff)) { 3900 op_len = be32_to_cpu(ophead->oh_len); 3901 } else { 3902 idx = BTOBBT((uintptr_t)&ophead->oh_len - 3903 (uintptr_t)iclog->ic_datap); 3904 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) { 3905 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3906 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3907 op_len = be32_to_cpu(xhdr[j].hic_xheader.xh_cycle_data[k]); 3908 } else { 3909 op_len = be32_to_cpu(iclog->ic_header.h_cycle_data[idx]); 3910 } 3911 } 3912 ptr += sizeof(xlog_op_header_t) + op_len; 3913 } 3914 } /* xlog_verify_iclog */ 3915 #endif 3916 3917 /* 3918 * Mark all iclogs IOERROR. l_icloglock is held by the caller. 3919 */ 3920 STATIC int 3921 xlog_state_ioerror( 3922 struct xlog *log) 3923 { 3924 xlog_in_core_t *iclog, *ic; 3925 3926 iclog = log->l_iclog; 3927 if (! (iclog->ic_state & XLOG_STATE_IOERROR)) { 3928 /* 3929 * Mark all the incore logs IOERROR. 3930 * From now on, no log flushes will result. 3931 */ 3932 ic = iclog; 3933 do { 3934 ic->ic_state = XLOG_STATE_IOERROR; 3935 ic = ic->ic_next; 3936 } while (ic != iclog); 3937 return 0; 3938 } 3939 /* 3940 * Return non-zero, if state transition has already happened. 3941 */ 3942 return 1; 3943 } 3944 3945 /* 3946 * This is called from xfs_force_shutdown, when we're forcibly 3947 * shutting down the filesystem, typically because of an IO error. 3948 * Our main objectives here are to make sure that: 3949 * a. if !logerror, flush the logs to disk. Anything modified 3950 * after this is ignored. 3951 * b. the filesystem gets marked 'SHUTDOWN' for all interested 3952 * parties to find out, 'atomically'. 3953 * c. those who're sleeping on log reservations, pinned objects and 3954 * other resources get woken up, and be told the bad news. 3955 * d. nothing new gets queued up after (b) and (c) are done. 3956 * 3957 * Note: for the !logerror case we need to flush the regions held in memory out 3958 * to disk first. This needs to be done before the log is marked as shutdown, 3959 * otherwise the iclog writes will fail. 3960 */ 3961 int 3962 xfs_log_force_umount( 3963 struct xfs_mount *mp, 3964 int logerror) 3965 { 3966 struct xlog *log; 3967 int retval; 3968 3969 log = mp->m_log; 3970 3971 /* 3972 * If this happens during log recovery, don't worry about 3973 * locking; the log isn't open for business yet. 3974 */ 3975 if (!log || 3976 log->l_flags & XLOG_ACTIVE_RECOVERY) { 3977 mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN; 3978 if (mp->m_sb_bp) 3979 mp->m_sb_bp->b_flags |= XBF_DONE; 3980 return 0; 3981 } 3982 3983 /* 3984 * Somebody could've already done the hard work for us. 3985 * No need to get locks for this. 3986 */ 3987 if (logerror && log->l_iclog->ic_state & XLOG_STATE_IOERROR) { 3988 ASSERT(XLOG_FORCED_SHUTDOWN(log)); 3989 return 1; 3990 } 3991 3992 /* 3993 * Flush all the completed transactions to disk before marking the log 3994 * being shut down. We need to do it in this order to ensure that 3995 * completed operations are safely on disk before we shut down, and that 3996 * we don't have to issue any buffer IO after the shutdown flags are set 3997 * to guarantee this. 3998 */ 3999 if (!logerror) 4000 xfs_log_force(mp, XFS_LOG_SYNC); 4001 4002 /* 4003 * mark the filesystem and the as in a shutdown state and wake 4004 * everybody up to tell them the bad news. 4005 */ 4006 spin_lock(&log->l_icloglock); 4007 mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN; 4008 if (mp->m_sb_bp) 4009 mp->m_sb_bp->b_flags |= XBF_DONE; 4010 4011 /* 4012 * Mark the log and the iclogs with IO error flags to prevent any 4013 * further log IO from being issued or completed. 4014 */ 4015 log->l_flags |= XLOG_IO_ERROR; 4016 retval = xlog_state_ioerror(log); 4017 spin_unlock(&log->l_icloglock); 4018 4019 /* 4020 * We don't want anybody waiting for log reservations after this. That 4021 * means we have to wake up everybody queued up on reserveq as well as 4022 * writeq. In addition, we make sure in xlog_{re}grant_log_space that 4023 * we don't enqueue anything once the SHUTDOWN flag is set, and this 4024 * action is protected by the grant locks. 4025 */ 4026 xlog_grant_head_wake_all(&log->l_reserve_head); 4027 xlog_grant_head_wake_all(&log->l_write_head); 4028 4029 /* 4030 * Wake up everybody waiting on xfs_log_force. Wake the CIL push first 4031 * as if the log writes were completed. The abort handling in the log 4032 * item committed callback functions will do this again under lock to 4033 * avoid races. 4034 */ 4035 wake_up_all(&log->l_cilp->xc_commit_wait); 4036 xlog_state_do_callback(log, XFS_LI_ABORTED, NULL); 4037 4038 #ifdef XFSERRORDEBUG 4039 { 4040 xlog_in_core_t *iclog; 4041 4042 spin_lock(&log->l_icloglock); 4043 iclog = log->l_iclog; 4044 do { 4045 ASSERT(iclog->ic_callback == 0); 4046 iclog = iclog->ic_next; 4047 } while (iclog != log->l_iclog); 4048 spin_unlock(&log->l_icloglock); 4049 } 4050 #endif 4051 /* return non-zero if log IOERROR transition had already happened */ 4052 return retval; 4053 } 4054 4055 STATIC int 4056 xlog_iclogs_empty( 4057 struct xlog *log) 4058 { 4059 xlog_in_core_t *iclog; 4060 4061 iclog = log->l_iclog; 4062 do { 4063 /* endianness does not matter here, zero is zero in 4064 * any language. 4065 */ 4066 if (iclog->ic_header.h_num_logops) 4067 return 0; 4068 iclog = iclog->ic_next; 4069 } while (iclog != log->l_iclog); 4070 return 1; 4071 } 4072 4073 /* 4074 * Verify that an LSN stamped into a piece of metadata is valid. This is 4075 * intended for use in read verifiers on v5 superblocks. 4076 */ 4077 bool 4078 xfs_log_check_lsn( 4079 struct xfs_mount *mp, 4080 xfs_lsn_t lsn) 4081 { 4082 struct xlog *log = mp->m_log; 4083 bool valid; 4084 4085 /* 4086 * norecovery mode skips mount-time log processing and unconditionally 4087 * resets the in-core LSN. We can't validate in this mode, but 4088 * modifications are not allowed anyways so just return true. 4089 */ 4090 if (mp->m_flags & XFS_MOUNT_NORECOVERY) 4091 return true; 4092 4093 /* 4094 * Some metadata LSNs are initialized to NULL (e.g., the agfl). This is 4095 * handled by recovery and thus safe to ignore here. 4096 */ 4097 if (lsn == NULLCOMMITLSN) 4098 return true; 4099 4100 valid = xlog_valid_lsn(mp->m_log, lsn); 4101 4102 /* warn the user about what's gone wrong before verifier failure */ 4103 if (!valid) { 4104 spin_lock(&log->l_icloglock); 4105 xfs_warn(mp, 4106 "Corruption warning: Metadata has LSN (%d:%d) ahead of current LSN (%d:%d). " 4107 "Please unmount and run xfs_repair (>= v4.3) to resolve.", 4108 CYCLE_LSN(lsn), BLOCK_LSN(lsn), 4109 log->l_curr_cycle, log->l_curr_block); 4110 spin_unlock(&log->l_icloglock); 4111 } 4112 4113 return valid; 4114 } 4115 4116 bool 4117 xfs_log_in_recovery( 4118 struct xfs_mount *mp) 4119 { 4120 struct xlog *log = mp->m_log; 4121 4122 return log->l_flags & XLOG_ACTIVE_RECOVERY; 4123 } 4124