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1// SPDX-License-Identifier: GPL-2.02/*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_trace.h"20#include "xfs_sysfs.h"21#include "xfs_sb.h"22#include "xfs_health.h"23 24struct kmem_cache *xfs_log_ticket_cache;25 26/* Local miscellaneous function prototypes */27STATIC struct xlog *28xlog_alloc_log(29 struct xfs_mount *mp,30 struct xfs_buftarg *log_target,31 xfs_daddr_t blk_offset,32 int num_bblks);33STATIC void34xlog_dealloc_log(35 struct xlog *log);36 37/* local state machine functions */38STATIC void xlog_state_done_syncing(39 struct xlog_in_core *iclog);40STATIC void xlog_state_do_callback(41 struct xlog *log);42STATIC int43xlog_state_get_iclog_space(44 struct xlog *log,45 int len,46 struct xlog_in_core **iclog,47 struct xlog_ticket *ticket,48 int *logoffsetp);49STATIC void50xlog_sync(51 struct xlog *log,52 struct xlog_in_core *iclog,53 struct xlog_ticket *ticket);54#if defined(DEBUG)55STATIC void56xlog_verify_iclog(57 struct xlog *log,58 struct xlog_in_core *iclog,59 int count);60STATIC void61xlog_verify_tail_lsn(62 struct xlog *log,63 struct xlog_in_core *iclog);64#else65#define xlog_verify_iclog(a,b,c)66#define xlog_verify_tail_lsn(a,b)67#endif68 69STATIC int70xlog_iclogs_empty(71 struct xlog *log);72 73static int74xfs_log_cover(struct xfs_mount *);75 76/*77 * We need to make sure the buffer pointer returned is naturally aligned for the78 * biggest basic data type we put into it. We have already accounted for this79 * padding when sizing the buffer.80 *81 * However, this padding does not get written into the log, and hence we have to82 * track the space used by the log vectors separately to prevent log space hangs83 * due to inaccurate accounting (i.e. a leak) of the used log space through the84 * CIL context ticket.85 *86 * We also add space for the xlog_op_header that describes this region in the87 * log. This prepends the data region we return to the caller to copy their data88 * into, so do all the static initialisation of the ophdr now. Because the ophdr89 * is not 8 byte aligned, we have to be careful to ensure that we align the90 * start of the buffer such that the region we return to the call is 8 byte91 * aligned and packed against the tail of the ophdr.92 */93void *94xlog_prepare_iovec(95 struct xfs_log_vec *lv,96 struct xfs_log_iovec **vecp,97 uint type)98{99 struct xfs_log_iovec *vec = *vecp;100 struct xlog_op_header *oph;101 uint32_t len;102 void *buf;103 104 if (vec) {105 ASSERT(vec - lv->lv_iovecp < lv->lv_niovecs);106 vec++;107 } else {108 vec = &lv->lv_iovecp[0];109 }110 111 len = lv->lv_buf_len + sizeof(struct xlog_op_header);112 if (!IS_ALIGNED(len, sizeof(uint64_t))) {113 lv->lv_buf_len = round_up(len, sizeof(uint64_t)) -114 sizeof(struct xlog_op_header);115 }116 117 vec->i_type = type;118 vec->i_addr = lv->lv_buf + lv->lv_buf_len;119 120 oph = vec->i_addr;121 oph->oh_clientid = XFS_TRANSACTION;122 oph->oh_res2 = 0;123 oph->oh_flags = 0;124 125 buf = vec->i_addr + sizeof(struct xlog_op_header);126 ASSERT(IS_ALIGNED((unsigned long)buf, sizeof(uint64_t)));127 128 *vecp = vec;129 return buf;130}131 132static inline void133xlog_grant_sub_space(134 struct xlog_grant_head *head,135 int64_t bytes)136{137 atomic64_sub(bytes, &head->grant);138}139 140static inline void141xlog_grant_add_space(142 struct xlog_grant_head *head,143 int64_t bytes)144{145 atomic64_add(bytes, &head->grant);146}147 148static void149xlog_grant_head_init(150 struct xlog_grant_head *head)151{152 atomic64_set(&head->grant, 0);153 INIT_LIST_HEAD(&head->waiters);154 spin_lock_init(&head->lock);155}156 157void158xlog_grant_return_space(159 struct xlog *log,160 xfs_lsn_t old_head,161 xfs_lsn_t new_head)162{163 int64_t diff = xlog_lsn_sub(log, new_head, old_head);164 165 xlog_grant_sub_space(&log->l_reserve_head, diff);166 xlog_grant_sub_space(&log->l_write_head, diff);167}168 169/*170 * Return the space in the log between the tail and the head. In the case where171 * we have overrun available reservation space, return 0. The memory barrier172 * pairs with the smp_wmb() in xlog_cil_ail_insert() to ensure that grant head173 * vs tail space updates are seen in the correct order and hence avoid174 * transients as space is transferred from the grant heads to the AIL on commit175 * completion.176 */177static uint64_t178xlog_grant_space_left(179 struct xlog *log,180 struct xlog_grant_head *head)181{182 int64_t free_bytes;183 184 smp_rmb(); /* paired with smp_wmb in xlog_cil_ail_insert() */185 free_bytes = log->l_logsize - READ_ONCE(log->l_tail_space) -186 atomic64_read(&head->grant);187 if (free_bytes > 0)188 return free_bytes;189 return 0;190}191 192STATIC void193xlog_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 204static inline int205xlog_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 }214 215 if (tic->t_flags & XLOG_TIC_PERM_RESERV)216 return tic->t_unit_res * tic->t_cnt;217 218 return tic->t_unit_res;219}220 221STATIC bool222xlog_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 243STATIC int244xlog_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_is_shutdown(log))255 goto shutdown;256 257 __set_current_state(TASK_UNINTERRUPTIBLE);258 spin_unlock(&head->lock);259 260 XFS_STATS_INC(log->l_mp, xs_sleep_logspace);261 262 /* Push on the AIL to free up all the log space. */263 xfs_ail_push_all(log->l_ailp);264 265 trace_xfs_log_grant_sleep(log, tic);266 schedule();267 trace_xfs_log_grant_wake(log, tic);268 269 spin_lock(&head->lock);270 if (xlog_is_shutdown(log))271 goto shutdown;272 } while (xlog_grant_space_left(log, head) < need_bytes);273 274 list_del_init(&tic->t_queue);275 return 0;276shutdown:277 list_del_init(&tic->t_queue);278 return -EIO;279}280 281/*282 * Atomically get the log space required for a log ticket.283 *284 * Once a ticket gets put onto head->waiters, it will only return after the285 * needed reservation is satisfied.286 *287 * This function is structured so that it has a lock free fast path. This is288 * necessary because every new transaction reservation will come through this289 * path. Hence any lock will be globally hot if we take it unconditionally on290 * every pass.291 *292 * As tickets are only ever moved on and off head->waiters under head->lock, we293 * only need to take that lock if we are going to add the ticket to the queue294 * and sleep. We can avoid taking the lock if the ticket was never added to295 * head->waiters because the t_queue list head will be empty and we hold the296 * only reference to it so it can safely be checked unlocked.297 */298STATIC int299xlog_grant_head_check(300 struct xlog *log,301 struct xlog_grant_head *head,302 struct xlog_ticket *tic,303 int *need_bytes)304{305 int free_bytes;306 int error = 0;307 308 ASSERT(!xlog_in_recovery(log));309 310 /*311 * If there are other waiters on the queue then give them a chance at312 * logspace before us. Wake up the first waiters, if we do not wake313 * up all the waiters then go to sleep waiting for more free space,314 * otherwise try to get some space for this transaction.315 */316 *need_bytes = xlog_ticket_reservation(log, head, tic);317 free_bytes = xlog_grant_space_left(log, head);318 if (!list_empty_careful(&head->waiters)) {319 spin_lock(&head->lock);320 if (!xlog_grant_head_wake(log, head, &free_bytes) ||321 free_bytes < *need_bytes) {322 error = xlog_grant_head_wait(log, head, tic,323 *need_bytes);324 }325 spin_unlock(&head->lock);326 } else if (free_bytes < *need_bytes) {327 spin_lock(&head->lock);328 error = xlog_grant_head_wait(log, head, tic, *need_bytes);329 spin_unlock(&head->lock);330 }331 332 return error;333}334 335bool336xfs_log_writable(337 struct xfs_mount *mp)338{339 /*340 * Do not write to the log on norecovery mounts, if the data or log341 * devices are read-only, or if the filesystem is shutdown. Read-only342 * mounts allow internal writes for log recovery and unmount purposes,343 * so don't restrict that case.344 */345 if (xfs_has_norecovery(mp))346 return false;347 if (xfs_readonly_buftarg(mp->m_ddev_targp))348 return false;349 if (xfs_readonly_buftarg(mp->m_log->l_targ))350 return false;351 if (xlog_is_shutdown(mp->m_log))352 return false;353 return true;354}355 356/*357 * Replenish the byte reservation required by moving the grant write head.358 */359int360xfs_log_regrant(361 struct xfs_mount *mp,362 struct xlog_ticket *tic)363{364 struct xlog *log = mp->m_log;365 int need_bytes;366 int error = 0;367 368 if (xlog_is_shutdown(log))369 return -EIO;370 371 XFS_STATS_INC(mp, xs_try_logspace);372 373 /*374 * This is a new transaction on the ticket, so we need to change the375 * transaction ID so that the next transaction has a different TID in376 * the log. Just add one to the existing tid so that we can see chains377 * of rolling transactions in the log easily.378 */379 tic->t_tid++;380 tic->t_curr_res = tic->t_unit_res;381 if (tic->t_cnt > 0)382 return 0;383 384 trace_xfs_log_regrant(log, tic);385 386 error = xlog_grant_head_check(log, &log->l_write_head, tic,387 &need_bytes);388 if (error)389 goto out_error;390 391 xlog_grant_add_space(&log->l_write_head, need_bytes);392 trace_xfs_log_regrant_exit(log, tic);393 return 0;394 395out_error:396 /*397 * If we are failing, make sure the ticket doesn't have any current398 * reservations. We don't want to add this back when the ticket/399 * transaction gets cancelled.400 */401 tic->t_curr_res = 0;402 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */403 return error;404}405 406/*407 * Reserve log space and return a ticket corresponding to the reservation.408 *409 * Each reservation is going to reserve extra space for a log record header.410 * When writes happen to the on-disk log, we don't subtract the length of the411 * log record header from any reservation. By wasting space in each412 * reservation, we prevent over allocation problems.413 */414int415xfs_log_reserve(416 struct xfs_mount *mp,417 int unit_bytes,418 int cnt,419 struct xlog_ticket **ticp,420 bool permanent)421{422 struct xlog *log = mp->m_log;423 struct xlog_ticket *tic;424 int need_bytes;425 int error = 0;426 427 if (xlog_is_shutdown(log))428 return -EIO;429 430 XFS_STATS_INC(mp, xs_try_logspace);431 432 ASSERT(*ticp == NULL);433 tic = xlog_ticket_alloc(log, unit_bytes, cnt, permanent);434 *ticp = tic;435 trace_xfs_log_reserve(log, tic);436 error = xlog_grant_head_check(log, &log->l_reserve_head, tic,437 &need_bytes);438 if (error)439 goto out_error;440 441 xlog_grant_add_space(&log->l_reserve_head, need_bytes);442 xlog_grant_add_space(&log->l_write_head, need_bytes);443 trace_xfs_log_reserve_exit(log, tic);444 return 0;445 446out_error:447 /*448 * If we are failing, make sure the ticket doesn't have any current449 * reservations. We don't want to add this back when the ticket/450 * transaction gets cancelled.451 */452 tic->t_curr_res = 0;453 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */454 return error;455}456 457/*458 * Run all the pending iclog callbacks and wake log force waiters and iclog459 * space waiters so they can process the newly set shutdown state. We really460 * don't care what order we process callbacks here because the log is shut down461 * and so state cannot change on disk anymore. However, we cannot wake waiters462 * until the callbacks have been processed because we may be in unmount and463 * we must ensure that all AIL operations the callbacks perform have completed464 * before we tear down the AIL.465 *466 * We avoid processing actively referenced iclogs so that we don't run callbacks467 * while the iclog owner might still be preparing the iclog for IO submssion.468 * These will be caught by xlog_state_iclog_release() and call this function469 * again to process any callbacks that may have been added to that iclog.470 */471static void472xlog_state_shutdown_callbacks(473 struct xlog *log)474{475 struct xlog_in_core *iclog;476 LIST_HEAD(cb_list);477 478 iclog = log->l_iclog;479 do {480 if (atomic_read(&iclog->ic_refcnt)) {481 /* Reference holder will re-run iclog callbacks. */482 continue;483 }484 list_splice_init(&iclog->ic_callbacks, &cb_list);485 spin_unlock(&log->l_icloglock);486 487 xlog_cil_process_committed(&cb_list);488 489 spin_lock(&log->l_icloglock);490 wake_up_all(&iclog->ic_write_wait);491 wake_up_all(&iclog->ic_force_wait);492 } while ((iclog = iclog->ic_next) != log->l_iclog);493 494 wake_up_all(&log->l_flush_wait);495}496 497/*498 * Flush iclog to disk if this is the last reference to the given iclog and the499 * it is in the WANT_SYNC state.500 *501 * If XLOG_ICL_NEED_FUA is already set on the iclog, we need to ensure that the502 * log tail is updated correctly. NEED_FUA indicates that the iclog will be503 * written to stable storage, and implies that a commit record is contained504 * within the iclog. We need to ensure that the log tail does not move beyond505 * the tail that the first commit record in the iclog ordered against, otherwise506 * correct recovery of that checkpoint becomes dependent on future operations507 * performed on this iclog.508 *509 * Hence if NEED_FUA is set and the current iclog tail lsn is empty, write the510 * current tail into iclog. Once the iclog tail is set, future operations must511 * not modify it, otherwise they potentially violate ordering constraints for512 * the checkpoint commit that wrote the initial tail lsn value. The tail lsn in513 * the iclog will get zeroed on activation of the iclog after sync, so we514 * always capture the tail lsn on the iclog on the first NEED_FUA release515 * regardless of the number of active reference counts on this iclog.516 */517int518xlog_state_release_iclog(519 struct xlog *log,520 struct xlog_in_core *iclog,521 struct xlog_ticket *ticket)522{523 bool last_ref;524 525 lockdep_assert_held(&log->l_icloglock);526 527 trace_xlog_iclog_release(iclog, _RET_IP_);528 /*529 * Grabbing the current log tail needs to be atomic w.r.t. the writing530 * of the tail LSN into the iclog so we guarantee that the log tail does531 * not move between the first time we know that the iclog needs to be532 * made stable and when we eventually submit it.533 */534 if ((iclog->ic_state == XLOG_STATE_WANT_SYNC ||535 (iclog->ic_flags & XLOG_ICL_NEED_FUA)) &&536 !iclog->ic_header.h_tail_lsn) {537 iclog->ic_header.h_tail_lsn =538 cpu_to_be64(atomic64_read(&log->l_tail_lsn));539 }540 541 last_ref = atomic_dec_and_test(&iclog->ic_refcnt);542 543 if (xlog_is_shutdown(log)) {544 /*545 * If there are no more references to this iclog, process the546 * pending iclog callbacks that were waiting on the release of547 * this iclog.548 */549 if (last_ref)550 xlog_state_shutdown_callbacks(log);551 return -EIO;552 }553 554 if (!last_ref)555 return 0;556 557 if (iclog->ic_state != XLOG_STATE_WANT_SYNC) {558 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);559 return 0;560 }561 562 iclog->ic_state = XLOG_STATE_SYNCING;563 xlog_verify_tail_lsn(log, iclog);564 trace_xlog_iclog_syncing(iclog, _RET_IP_);565 566 spin_unlock(&log->l_icloglock);567 xlog_sync(log, iclog, ticket);568 spin_lock(&log->l_icloglock);569 return 0;570}571 572/*573 * Mount a log filesystem574 *575 * mp - ubiquitous xfs mount point structure576 * log_target - buftarg of on-disk log device577 * blk_offset - Start block # where block size is 512 bytes (BBSIZE)578 * num_bblocks - Number of BBSIZE blocks in on-disk log579 *580 * Return error or zero.581 */582int583xfs_log_mount(584 xfs_mount_t *mp,585 struct xfs_buftarg *log_target,586 xfs_daddr_t blk_offset,587 int num_bblks)588{589 struct xlog *log;590 int error = 0;591 int min_logfsbs;592 593 if (!xfs_has_norecovery(mp)) {594 xfs_notice(mp, "Mounting V%d Filesystem %pU",595 XFS_SB_VERSION_NUM(&mp->m_sb),596 &mp->m_sb.sb_uuid);597 } else {598 xfs_notice(mp,599"Mounting V%d filesystem %pU in no-recovery mode. Filesystem will be inconsistent.",600 XFS_SB_VERSION_NUM(&mp->m_sb),601 &mp->m_sb.sb_uuid);602 ASSERT(xfs_is_readonly(mp));603 }604 605 log = xlog_alloc_log(mp, log_target, blk_offset, num_bblks);606 if (IS_ERR(log)) {607 error = PTR_ERR(log);608 goto out;609 }610 mp->m_log = log;611 612 /*613 * Now that we have set up the log and it's internal geometry614 * parameters, we can validate the given log space and drop a critical615 * message via syslog if the log size is too small. A log that is too616 * small can lead to unexpected situations in transaction log space617 * reservation stage. The superblock verifier has already validated all618 * the other log geometry constraints, so we don't have to check those619 * here.620 *621 * Note: For v4 filesystems, we can't just reject the mount if the622 * validation fails. This would mean that people would have to623 * downgrade their kernel just to remedy the situation as there is no624 * way to grow the log (short of black magic surgery with xfs_db).625 *626 * We can, however, reject mounts for V5 format filesystems, as the627 * mkfs binary being used to make the filesystem should never create a628 * filesystem with a log that is too small.629 */630 min_logfsbs = xfs_log_calc_minimum_size(mp);631 if (mp->m_sb.sb_logblocks < min_logfsbs) {632 xfs_warn(mp,633 "Log size %d blocks too small, minimum size is %d blocks",634 mp->m_sb.sb_logblocks, min_logfsbs);635 636 /*637 * Log check errors are always fatal on v5; or whenever bad638 * metadata leads to a crash.639 */640 if (xfs_has_crc(mp)) {641 xfs_crit(mp, "AAIEEE! Log failed size checks. Abort!");642 ASSERT(0);643 error = -EINVAL;644 goto out_free_log;645 }646 xfs_crit(mp, "Log size out of supported range.");647 xfs_crit(mp,648"Continuing onwards, but if log hangs are experienced then please report this message in the bug report.");649 }650 651 /*652 * Initialize the AIL now we have a log.653 */654 error = xfs_trans_ail_init(mp);655 if (error) {656 xfs_warn(mp, "AIL initialisation failed: error %d", error);657 goto out_free_log;658 }659 log->l_ailp = mp->m_ail;660 661 /*662 * skip log recovery on a norecovery mount. pretend it all663 * just worked.664 */665 if (!xfs_has_norecovery(mp)) {666 error = xlog_recover(log);667 if (error) {668 xfs_warn(mp, "log mount/recovery failed: error %d",669 error);670 xlog_recover_cancel(log);671 goto out_destroy_ail;672 }673 }674 675 error = xfs_sysfs_init(&log->l_kobj, &xfs_log_ktype, &mp->m_kobj,676 "log");677 if (error)678 goto out_destroy_ail;679 680 /* Normal transactions can now occur */681 clear_bit(XLOG_ACTIVE_RECOVERY, &log->l_opstate);682 683 /*684 * Now the log has been fully initialised and we know were our685 * space grant counters are, we can initialise the permanent ticket686 * needed for delayed logging to work.687 */688 xlog_cil_init_post_recovery(log);689 690 return 0;691 692out_destroy_ail:693 xfs_trans_ail_destroy(mp);694out_free_log:695 xlog_dealloc_log(log);696out:697 return error;698}699 700/*701 * Finish the recovery of the file system. This is separate from the702 * xfs_log_mount() call, because it depends on the code in xfs_mountfs() to read703 * in the root and real-time bitmap inodes between calling xfs_log_mount() and704 * here.705 *706 * If we finish recovery successfully, start the background log work. If we are707 * not doing recovery, then we have a RO filesystem and we don't need to start708 * it.709 */710int711xfs_log_mount_finish(712 struct xfs_mount *mp)713{714 struct xlog *log = mp->m_log;715 int error = 0;716 717 if (xfs_has_norecovery(mp)) {718 ASSERT(xfs_is_readonly(mp));719 return 0;720 }721 722 /*723 * During the second phase of log recovery, we need iget and724 * iput to behave like they do for an active filesystem.725 * xfs_fs_drop_inode needs to be able to prevent the deletion726 * of inodes before we're done replaying log items on those727 * inodes. Turn it off immediately after recovery finishes728 * so that we don't leak the quota inodes if subsequent mount729 * activities fail.730 *731 * We let all inodes involved in redo item processing end up on732 * the LRU instead of being evicted immediately so that if we do733 * something to an unlinked inode, the irele won't cause734 * premature truncation and freeing of the inode, which results735 * in log recovery failure. We have to evict the unreferenced736 * lru inodes after clearing SB_ACTIVE because we don't737 * otherwise clean up the lru if there's a subsequent failure in738 * xfs_mountfs, which leads to us leaking the inodes if nothing739 * else (e.g. quotacheck) references the inodes before the740 * mount failure occurs.741 */742 mp->m_super->s_flags |= SB_ACTIVE;743 xfs_log_work_queue(mp);744 if (xlog_recovery_needed(log))745 error = xlog_recover_finish(log);746 mp->m_super->s_flags &= ~SB_ACTIVE;747 evict_inodes(mp->m_super);748 749 /*750 * Drain the buffer LRU after log recovery. This is required for v4751 * filesystems to avoid leaving around buffers with NULL verifier ops,752 * but we do it unconditionally to make sure we're always in a clean753 * cache state after mount.754 *755 * Don't push in the error case because the AIL may have pending intents756 * that aren't removed until recovery is cancelled.757 */758 if (xlog_recovery_needed(log)) {759 if (!error) {760 xfs_log_force(mp, XFS_LOG_SYNC);761 xfs_ail_push_all_sync(mp->m_ail);762 }763 xfs_notice(mp, "Ending recovery (logdev: %s)",764 mp->m_logname ? mp->m_logname : "internal");765 } else {766 xfs_info(mp, "Ending clean mount");767 }768 xfs_buftarg_drain(mp->m_ddev_targp);769 770 clear_bit(XLOG_RECOVERY_NEEDED, &log->l_opstate);771 772 /* Make sure the log is dead if we're returning failure. */773 ASSERT(!error || xlog_is_shutdown(log));774 775 return error;776}777 778/*779 * The mount has failed. Cancel the recovery if it hasn't completed and destroy780 * the log.781 */782void783xfs_log_mount_cancel(784 struct xfs_mount *mp)785{786 xlog_recover_cancel(mp->m_log);787 xfs_log_unmount(mp);788}789 790/*791 * Flush out the iclog to disk ensuring that device caches are flushed and792 * the iclog hits stable storage before any completion waiters are woken.793 */794static inline int795xlog_force_iclog(796 struct xlog_in_core *iclog)797{798 atomic_inc(&iclog->ic_refcnt);799 iclog->ic_flags |= XLOG_ICL_NEED_FLUSH | XLOG_ICL_NEED_FUA;800 if (iclog->ic_state == XLOG_STATE_ACTIVE)801 xlog_state_switch_iclogs(iclog->ic_log, iclog, 0);802 return xlog_state_release_iclog(iclog->ic_log, iclog, NULL);803}804 805/*806 * Cycle all the iclogbuf locks to make sure all log IO completion807 * is done before we tear down these buffers.808 */809static void810xlog_wait_iclog_completion(struct xlog *log)811{812 int i;813 struct xlog_in_core *iclog = log->l_iclog;814 815 for (i = 0; i < log->l_iclog_bufs; i++) {816 down(&iclog->ic_sema);817 up(&iclog->ic_sema);818 iclog = iclog->ic_next;819 }820}821 822/*823 * Wait for the iclog and all prior iclogs to be written disk as required by the824 * log force state machine. Waiting on ic_force_wait ensures iclog completions825 * have been ordered and callbacks run before we are woken here, hence826 * guaranteeing that all the iclogs up to this one are on stable storage.827 */828int829xlog_wait_on_iclog(830 struct xlog_in_core *iclog)831 __releases(iclog->ic_log->l_icloglock)832{833 struct xlog *log = iclog->ic_log;834 835 trace_xlog_iclog_wait_on(iclog, _RET_IP_);836 if (!xlog_is_shutdown(log) &&837 iclog->ic_state != XLOG_STATE_ACTIVE &&838 iclog->ic_state != XLOG_STATE_DIRTY) {839 XFS_STATS_INC(log->l_mp, xs_log_force_sleep);840 xlog_wait(&iclog->ic_force_wait, &log->l_icloglock);841 } else {842 spin_unlock(&log->l_icloglock);843 }844 845 if (xlog_is_shutdown(log))846 return -EIO;847 return 0;848}849 850/*851 * Write out an unmount record using the ticket provided. We have to account for852 * the data space used in the unmount ticket as this write is not done from a853 * transaction context that has already done the accounting for us.854 */855static int856xlog_write_unmount_record(857 struct xlog *log,858 struct xlog_ticket *ticket)859{860 struct {861 struct xlog_op_header ophdr;862 struct xfs_unmount_log_format ulf;863 } unmount_rec = {864 .ophdr = {865 .oh_clientid = XFS_LOG,866 .oh_tid = cpu_to_be32(ticket->t_tid),867 .oh_flags = XLOG_UNMOUNT_TRANS,868 },869 .ulf = {870 .magic = XLOG_UNMOUNT_TYPE,871 },872 };873 struct xfs_log_iovec reg = {874 .i_addr = &unmount_rec,875 .i_len = sizeof(unmount_rec),876 .i_type = XLOG_REG_TYPE_UNMOUNT,877 };878 struct xfs_log_vec vec = {879 .lv_niovecs = 1,880 .lv_iovecp = ®,881 };882 LIST_HEAD(lv_chain);883 list_add(&vec.lv_list, &lv_chain);884 885 BUILD_BUG_ON((sizeof(struct xlog_op_header) +886 sizeof(struct xfs_unmount_log_format)) !=887 sizeof(unmount_rec));888 889 /* account for space used by record data */890 ticket->t_curr_res -= sizeof(unmount_rec);891 892 return xlog_write(log, NULL, &lv_chain, ticket, reg.i_len);893}894 895/*896 * Mark the filesystem clean by writing an unmount record to the head of the897 * log.898 */899static void900xlog_unmount_write(901 struct xlog *log)902{903 struct xfs_mount *mp = log->l_mp;904 struct xlog_in_core *iclog;905 struct xlog_ticket *tic = NULL;906 int error;907 908 error = xfs_log_reserve(mp, 600, 1, &tic, 0);909 if (error)910 goto out_err;911 912 error = xlog_write_unmount_record(log, tic);913 /*914 * At this point, we're umounting anyway, so there's no point in915 * transitioning log state to shutdown. Just continue...916 */917out_err:918 if (error)919 xfs_alert(mp, "%s: unmount record failed", __func__);920 921 spin_lock(&log->l_icloglock);922 iclog = log->l_iclog;923 error = xlog_force_iclog(iclog);924 xlog_wait_on_iclog(iclog);925 926 if (tic) {927 trace_xfs_log_umount_write(log, tic);928 xfs_log_ticket_ungrant(log, tic);929 }930}931 932static void933xfs_log_unmount_verify_iclog(934 struct xlog *log)935{936 struct xlog_in_core *iclog = log->l_iclog;937 938 do {939 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);940 ASSERT(iclog->ic_offset == 0);941 } while ((iclog = iclog->ic_next) != log->l_iclog);942}943 944/*945 * Unmount record used to have a string "Unmount filesystem--" in the946 * data section where the "Un" was really a magic number (XLOG_UNMOUNT_TYPE).947 * We just write the magic number now since that particular field isn't948 * currently architecture converted and "Unmount" is a bit foo.949 * As far as I know, there weren't any dependencies on the old behaviour.950 */951static void952xfs_log_unmount_write(953 struct xfs_mount *mp)954{955 struct xlog *log = mp->m_log;956 957 if (!xfs_log_writable(mp))958 return;959 960 xfs_log_force(mp, XFS_LOG_SYNC);961 962 if (xlog_is_shutdown(log))963 return;964 965 /*966 * If we think the summary counters are bad, avoid writing the unmount967 * record to force log recovery at next mount, after which the summary968 * counters will be recalculated. Refer to xlog_check_unmount_rec for969 * more details.970 */971 if (XFS_TEST_ERROR(xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS), mp,972 XFS_ERRTAG_FORCE_SUMMARY_RECALC)) {973 xfs_alert(mp, "%s: will fix summary counters at next mount",974 __func__);975 return;976 }977 978 xfs_log_unmount_verify_iclog(log);979 xlog_unmount_write(log);980}981 982/*983 * Empty the log for unmount/freeze.984 *985 * To do this, we first need to shut down the background log work so it is not986 * trying to cover the log as we clean up. We then need to unpin all objects in987 * the log so we can then flush them out. Once they have completed their IO and988 * run the callbacks removing themselves from the AIL, we can cover the log.989 */990int991xfs_log_quiesce(992 struct xfs_mount *mp)993{994 /*995 * Clear log incompat features since we're quiescing the log. Report996 * failures, though it's not fatal to have a higher log feature997 * protection level than the log contents actually require.998 */999 if (xfs_clear_incompat_log_features(mp)) {1000 int error;1001 1002 error = xfs_sync_sb(mp, false);1003 if (error)1004 xfs_warn(mp,1005 "Failed to clear log incompat features on quiesce");1006 }1007 1008 cancel_delayed_work_sync(&mp->m_log->l_work);1009 xfs_log_force(mp, XFS_LOG_SYNC);1010 1011 /*1012 * The superblock buffer is uncached and while xfs_ail_push_all_sync()1013 * will push it, xfs_buftarg_wait() will not wait for it. Further,1014 * xfs_buf_iowait() cannot be used because it was pushed with the1015 * XBF_ASYNC flag set, so we need to use a lock/unlock pair to wait for1016 * the IO to complete.1017 */1018 xfs_ail_push_all_sync(mp->m_ail);1019 xfs_buftarg_wait(mp->m_ddev_targp);1020 xfs_buf_lock(mp->m_sb_bp);1021 xfs_buf_unlock(mp->m_sb_bp);1022 1023 return xfs_log_cover(mp);1024}1025 1026void1027xfs_log_clean(1028 struct xfs_mount *mp)1029{1030 xfs_log_quiesce(mp);1031 xfs_log_unmount_write(mp);1032}1033 1034/*1035 * Shut down and release the AIL and Log.1036 *1037 * During unmount, we need to ensure we flush all the dirty metadata objects1038 * from the AIL so that the log is empty before we write the unmount record to1039 * the log. Once this is done, we can tear down the AIL and the log.1040 */1041void1042xfs_log_unmount(1043 struct xfs_mount *mp)1044{1045 xfs_log_clean(mp);1046 1047 /*1048 * If shutdown has come from iclog IO context, the log1049 * cleaning will have been skipped and so we need to wait1050 * for the iclog to complete shutdown processing before we1051 * tear anything down.1052 */1053 xlog_wait_iclog_completion(mp->m_log);1054 1055 xfs_buftarg_drain(mp->m_ddev_targp);1056 1057 xfs_trans_ail_destroy(mp);1058 1059 xfs_sysfs_del(&mp->m_log->l_kobj);1060 1061 xlog_dealloc_log(mp->m_log);1062}1063 1064void1065xfs_log_item_init(1066 struct xfs_mount *mp,1067 struct xfs_log_item *item,1068 int type,1069 const struct xfs_item_ops *ops)1070{1071 item->li_log = mp->m_log;1072 item->li_ailp = mp->m_ail;1073 item->li_type = type;1074 item->li_ops = ops;1075 item->li_lv = NULL;1076 1077 INIT_LIST_HEAD(&item->li_ail);1078 INIT_LIST_HEAD(&item->li_cil);1079 INIT_LIST_HEAD(&item->li_bio_list);1080 INIT_LIST_HEAD(&item->li_trans);1081}1082 1083/*1084 * Wake up processes waiting for log space after we have moved the log tail.1085 */1086void1087xfs_log_space_wake(1088 struct xfs_mount *mp)1089{1090 struct xlog *log = mp->m_log;1091 int free_bytes;1092 1093 if (xlog_is_shutdown(log))1094 return;1095 1096 if (!list_empty_careful(&log->l_write_head.waiters)) {1097 ASSERT(!xlog_in_recovery(log));1098 1099 spin_lock(&log->l_write_head.lock);1100 free_bytes = xlog_grant_space_left(log, &log->l_write_head);1101 xlog_grant_head_wake(log, &log->l_write_head, &free_bytes);1102 spin_unlock(&log->l_write_head.lock);1103 }1104 1105 if (!list_empty_careful(&log->l_reserve_head.waiters)) {1106 ASSERT(!xlog_in_recovery(log));1107 1108 spin_lock(&log->l_reserve_head.lock);1109 free_bytes = xlog_grant_space_left(log, &log->l_reserve_head);1110 xlog_grant_head_wake(log, &log->l_reserve_head, &free_bytes);1111 spin_unlock(&log->l_reserve_head.lock);1112 }1113}1114 1115/*1116 * Determine if we have a transaction that has gone to disk that needs to be1117 * covered. To begin the transition to the idle state firstly the log needs to1118 * be idle. That means the CIL, the AIL and the iclogs needs to be empty before1119 * we start attempting to cover the log.1120 *1121 * Only if we are then in a state where covering is needed, the caller is1122 * informed that dummy transactions are required to move the log into the idle1123 * state.1124 *1125 * If there are any items in the AIl or CIL, then we do not want to attempt to1126 * cover the log as we may be in a situation where there isn't log space1127 * available to run a dummy transaction and this can lead to deadlocks when the1128 * tail of the log is pinned by an item that is modified in the CIL. Hence1129 * there's no point in running a dummy transaction at this point because we1130 * can't start trying to idle the log until both the CIL and AIL are empty.1131 */1132static bool1133xfs_log_need_covered(1134 struct xfs_mount *mp)1135{1136 struct xlog *log = mp->m_log;1137 bool needed = false;1138 1139 if (!xlog_cil_empty(log))1140 return false;1141 1142 spin_lock(&log->l_icloglock);1143 switch (log->l_covered_state) {1144 case XLOG_STATE_COVER_DONE:1145 case XLOG_STATE_COVER_DONE2:1146 case XLOG_STATE_COVER_IDLE:1147 break;1148 case XLOG_STATE_COVER_NEED:1149 case XLOG_STATE_COVER_NEED2:1150 if (xfs_ail_min_lsn(log->l_ailp))1151 break;1152 if (!xlog_iclogs_empty(log))1153 break;1154 1155 needed = true;1156 if (log->l_covered_state == XLOG_STATE_COVER_NEED)1157 log->l_covered_state = XLOG_STATE_COVER_DONE;1158 else1159 log->l_covered_state = XLOG_STATE_COVER_DONE2;1160 break;1161 default:1162 needed = true;1163 break;1164 }1165 spin_unlock(&log->l_icloglock);1166 return needed;1167}1168 1169/*1170 * Explicitly cover the log. This is similar to background log covering but1171 * intended for usage in quiesce codepaths. The caller is responsible to ensure1172 * the log is idle and suitable for covering. The CIL, iclog buffers and AIL1173 * must all be empty.1174 */1175static int1176xfs_log_cover(1177 struct xfs_mount *mp)1178{1179 int error = 0;1180 bool need_covered;1181 1182 ASSERT((xlog_cil_empty(mp->m_log) && xlog_iclogs_empty(mp->m_log) &&1183 !xfs_ail_min_lsn(mp->m_log->l_ailp)) ||1184 xlog_is_shutdown(mp->m_log));1185 1186 if (!xfs_log_writable(mp))1187 return 0;1188 1189 /*1190 * xfs_log_need_covered() is not idempotent because it progresses the1191 * state machine if the log requires covering. Therefore, we must call1192 * this function once and use the result until we've issued an sb sync.1193 * Do so first to make that abundantly clear.1194 *1195 * Fall into the covering sequence if the log needs covering or the1196 * mount has lazy superblock accounting to sync to disk. The sb sync1197 * used for covering accumulates the in-core counters, so covering1198 * handles this for us.1199 */1200 need_covered = xfs_log_need_covered(mp);1201 if (!need_covered && !xfs_has_lazysbcount(mp))1202 return 0;1203 1204 /*1205 * To cover the log, commit the superblock twice (at most) in1206 * independent checkpoints. The first serves as a reference for the1207 * tail pointer. The sync transaction and AIL push empties the AIL and1208 * updates the in-core tail to the LSN of the first checkpoint. The1209 * second commit updates the on-disk tail with the in-core LSN,1210 * covering the log. Push the AIL one more time to leave it empty, as1211 * we found it.1212 */1213 do {1214 error = xfs_sync_sb(mp, true);1215 if (error)1216 break;1217 xfs_ail_push_all_sync(mp->m_ail);1218 } while (xfs_log_need_covered(mp));1219 1220 return error;1221}1222 1223static void1224xlog_ioend_work(1225 struct work_struct *work)1226{1227 struct xlog_in_core *iclog =1228 container_of(work, struct xlog_in_core, ic_end_io_work);1229 struct xlog *log = iclog->ic_log;1230 int error;1231 1232 error = blk_status_to_errno(iclog->ic_bio.bi_status);1233#ifdef DEBUG1234 /* treat writes with injected CRC errors as failed */1235 if (iclog->ic_fail_crc)1236 error = -EIO;1237#endif1238 1239 /*1240 * Race to shutdown the filesystem if we see an error.1241 */1242 if (XFS_TEST_ERROR(error, log->l_mp, XFS_ERRTAG_IODONE_IOERR)) {1243 xfs_alert(log->l_mp, "log I/O error %d", error);1244 xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);1245 }1246 1247 xlog_state_done_syncing(iclog);1248 bio_uninit(&iclog->ic_bio);1249 1250 /*1251 * Drop the lock to signal that we are done. Nothing references the1252 * iclog after this, so an unmount waiting on this lock can now tear it1253 * down safely. As such, it is unsafe to reference the iclog after the1254 * unlock as we could race with it being freed.1255 */1256 up(&iclog->ic_sema);1257}1258 1259/*1260 * Return size of each in-core log record buffer.1261 *1262 * All machines get 8 x 32kB buffers by default, unless tuned otherwise.1263 *1264 * If the filesystem blocksize is too large, we may need to choose a1265 * larger size since the directory code currently logs entire blocks.1266 */1267STATIC void1268xlog_get_iclog_buffer_size(1269 struct xfs_mount *mp,1270 struct xlog *log)1271{1272 if (mp->m_logbufs <= 0)1273 mp->m_logbufs = XLOG_MAX_ICLOGS;1274 if (mp->m_logbsize <= 0)1275 mp->m_logbsize = XLOG_BIG_RECORD_BSIZE;1276 1277 log->l_iclog_bufs = mp->m_logbufs;1278 log->l_iclog_size = mp->m_logbsize;1279 1280 /*1281 * # headers = size / 32k - one header holds cycles from 32k of data.1282 */1283 log->l_iclog_heads =1284 DIV_ROUND_UP(mp->m_logbsize, XLOG_HEADER_CYCLE_SIZE);1285 log->l_iclog_hsize = log->l_iclog_heads << BBSHIFT;1286}1287 1288void1289xfs_log_work_queue(1290 struct xfs_mount *mp)1291{1292 queue_delayed_work(mp->m_sync_workqueue, &mp->m_log->l_work,1293 msecs_to_jiffies(xfs_syncd_centisecs * 10));1294}1295 1296/*1297 * Clear the log incompat flags if we have the opportunity.1298 *1299 * This only happens if we're about to log the second dummy transaction as part1300 * of covering the log.1301 */1302static inline void1303xlog_clear_incompat(1304 struct xlog *log)1305{1306 struct xfs_mount *mp = log->l_mp;1307 1308 if (!xfs_sb_has_incompat_log_feature(&mp->m_sb,1309 XFS_SB_FEAT_INCOMPAT_LOG_ALL))1310 return;1311 1312 if (log->l_covered_state != XLOG_STATE_COVER_DONE2)1313 return;1314 1315 xfs_clear_incompat_log_features(mp);1316}1317 1318/*1319 * Every sync period we need to unpin all items in the AIL and push them to1320 * disk. If there is nothing dirty, then we might need to cover the log to1321 * indicate that the filesystem is idle.1322 */1323static void1324xfs_log_worker(1325 struct work_struct *work)1326{1327 struct xlog *log = container_of(to_delayed_work(work),1328 struct xlog, l_work);1329 struct xfs_mount *mp = log->l_mp;1330 1331 /* dgc: errors ignored - not fatal and nowhere to report them */1332 if (xfs_fs_writable(mp, SB_FREEZE_WRITE) && xfs_log_need_covered(mp)) {1333 /*1334 * Dump a transaction into the log that contains no real change.1335 * This is needed to stamp the current tail LSN into the log1336 * during the covering operation.1337 *1338 * We cannot use an inode here for this - that will push dirty1339 * state back up into the VFS and then periodic inode flushing1340 * will prevent log covering from making progress. Hence we1341 * synchronously log the superblock instead to ensure the1342 * superblock is immediately unpinned and can be written back.1343 */1344 xlog_clear_incompat(log);1345 xfs_sync_sb(mp, true);1346 } else1347 xfs_log_force(mp, 0);1348 1349 /* start pushing all the metadata that is currently dirty */1350 xfs_ail_push_all(mp->m_ail);1351 1352 /* queue us up again */1353 xfs_log_work_queue(mp);1354}1355 1356/*1357 * This routine initializes some of the log structure for a given mount point.1358 * Its primary purpose is to fill in enough, so recovery can occur. However,1359 * some other stuff may be filled in too.1360 */1361STATIC struct xlog *1362xlog_alloc_log(1363 struct xfs_mount *mp,1364 struct xfs_buftarg *log_target,1365 xfs_daddr_t blk_offset,1366 int num_bblks)1367{1368 struct xlog *log;1369 xlog_rec_header_t *head;1370 xlog_in_core_t **iclogp;1371 xlog_in_core_t *iclog, *prev_iclog=NULL;1372 int i;1373 int error = -ENOMEM;1374 uint log2_size = 0;1375 1376 log = kzalloc(sizeof(struct xlog), GFP_KERNEL | __GFP_RETRY_MAYFAIL);1377 if (!log) {1378 xfs_warn(mp, "Log allocation failed: No memory!");1379 goto out;1380 }1381 1382 log->l_mp = mp;1383 log->l_targ = log_target;1384 log->l_logsize = BBTOB(num_bblks);1385 log->l_logBBstart = blk_offset;1386 log->l_logBBsize = num_bblks;1387 log->l_covered_state = XLOG_STATE_COVER_IDLE;1388 set_bit(XLOG_ACTIVE_RECOVERY, &log->l_opstate);1389 INIT_DELAYED_WORK(&log->l_work, xfs_log_worker);1390 INIT_LIST_HEAD(&log->r_dfops);1391 1392 log->l_prev_block = -1;1393 /* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */1394 xlog_assign_atomic_lsn(&log->l_tail_lsn, 1, 0);1395 log->l_curr_cycle = 1; /* 0 is bad since this is initial value */1396 1397 if (xfs_has_logv2(mp) && mp->m_sb.sb_logsunit > 1)1398 log->l_iclog_roundoff = mp->m_sb.sb_logsunit;1399 else1400 log->l_iclog_roundoff = BBSIZE;1401 1402 xlog_grant_head_init(&log->l_reserve_head);1403 xlog_grant_head_init(&log->l_write_head);1404 1405 error = -EFSCORRUPTED;1406 if (xfs_has_sector(mp)) {1407 log2_size = mp->m_sb.sb_logsectlog;1408 if (log2_size < BBSHIFT) {1409 xfs_warn(mp, "Log sector size too small (0x%x < 0x%x)",1410 log2_size, BBSHIFT);1411 goto out_free_log;1412 }1413 1414 log2_size -= BBSHIFT;1415 if (log2_size > mp->m_sectbb_log) {1416 xfs_warn(mp, "Log sector size too large (0x%x > 0x%x)",1417 log2_size, mp->m_sectbb_log);1418 goto out_free_log;1419 }1420 1421 /* for larger sector sizes, must have v2 or external log */1422 if (log2_size && log->l_logBBstart > 0 &&1423 !xfs_has_logv2(mp)) {1424 xfs_warn(mp,1425 "log sector size (0x%x) invalid for configuration.",1426 log2_size);1427 goto out_free_log;1428 }1429 }1430 log->l_sectBBsize = 1 << log2_size;1431 1432 xlog_get_iclog_buffer_size(mp, log);1433 1434 spin_lock_init(&log->l_icloglock);1435 init_waitqueue_head(&log->l_flush_wait);1436 1437 iclogp = &log->l_iclog;1438 /*1439 * The amount of memory to allocate for the iclog structure is1440 * rather funky due to the way the structure is defined. It is1441 * done this way so that we can use different sizes for machines1442 * with different amounts of memory. See the definition of1443 * xlog_in_core_t in xfs_log_priv.h for details.1444 */1445 ASSERT(log->l_iclog_size >= 4096);1446 for (i = 0; i < log->l_iclog_bufs; i++) {1447 size_t bvec_size = howmany(log->l_iclog_size, PAGE_SIZE) *1448 sizeof(struct bio_vec);1449 1450 iclog = kzalloc(sizeof(*iclog) + bvec_size,1451 GFP_KERNEL | __GFP_RETRY_MAYFAIL);1452 if (!iclog)1453 goto out_free_iclog;1454 1455 *iclogp = iclog;1456 iclog->ic_prev = prev_iclog;1457 prev_iclog = iclog;1458 1459 iclog->ic_data = kvzalloc(log->l_iclog_size,1460 GFP_KERNEL | __GFP_RETRY_MAYFAIL);1461 if (!iclog->ic_data)1462 goto out_free_iclog;1463 head = &iclog->ic_header;1464 memset(head, 0, sizeof(xlog_rec_header_t));1465 head->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);1466 head->h_version = cpu_to_be32(1467 xfs_has_logv2(log->l_mp) ? 2 : 1);1468 head->h_size = cpu_to_be32(log->l_iclog_size);1469 /* new fields */1470 head->h_fmt = cpu_to_be32(XLOG_FMT);1471 memcpy(&head->h_fs_uuid, &mp->m_sb.sb_uuid, sizeof(uuid_t));1472 1473 iclog->ic_size = log->l_iclog_size - log->l_iclog_hsize;1474 iclog->ic_state = XLOG_STATE_ACTIVE;1475 iclog->ic_log = log;1476 atomic_set(&iclog->ic_refcnt, 0);1477 INIT_LIST_HEAD(&iclog->ic_callbacks);1478 iclog->ic_datap = (void *)iclog->ic_data + log->l_iclog_hsize;1479 1480 init_waitqueue_head(&iclog->ic_force_wait);1481 init_waitqueue_head(&iclog->ic_write_wait);1482 INIT_WORK(&iclog->ic_end_io_work, xlog_ioend_work);1483 sema_init(&iclog->ic_sema, 1);1484 1485 iclogp = &iclog->ic_next;1486 }1487 *iclogp = log->l_iclog; /* complete ring */1488 log->l_iclog->ic_prev = prev_iclog; /* re-write 1st prev ptr */1489 1490 log->l_ioend_workqueue = alloc_workqueue("xfs-log/%s",1491 XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM |1492 WQ_HIGHPRI),1493 0, mp->m_super->s_id);1494 if (!log->l_ioend_workqueue)1495 goto out_free_iclog;1496 1497 error = xlog_cil_init(log);1498 if (error)1499 goto out_destroy_workqueue;1500 return log;1501 1502out_destroy_workqueue:1503 destroy_workqueue(log->l_ioend_workqueue);1504out_free_iclog:1505 for (iclog = log->l_iclog; iclog; iclog = prev_iclog) {1506 prev_iclog = iclog->ic_next;1507 kvfree(iclog->ic_data);1508 kfree(iclog);1509 if (prev_iclog == log->l_iclog)1510 break;1511 }1512out_free_log:1513 kfree(log);1514out:1515 return ERR_PTR(error);1516} /* xlog_alloc_log */1517 1518/*1519 * Stamp cycle number in every block1520 */1521STATIC void1522xlog_pack_data(1523 struct xlog *log,1524 struct xlog_in_core *iclog,1525 int roundoff)1526{1527 int i, j, k;1528 int size = iclog->ic_offset + roundoff;1529 __be32 cycle_lsn;1530 char *dp;1531 1532 cycle_lsn = CYCLE_LSN_DISK(iclog->ic_header.h_lsn);1533 1534 dp = iclog->ic_datap;1535 for (i = 0; i < BTOBB(size); i++) {1536 if (i >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE))1537 break;1538 iclog->ic_header.h_cycle_data[i] = *(__be32 *)dp;1539 *(__be32 *)dp = cycle_lsn;1540 dp += BBSIZE;1541 }1542 1543 if (xfs_has_logv2(log->l_mp)) {1544 xlog_in_core_2_t *xhdr = iclog->ic_data;1545 1546 for ( ; i < BTOBB(size); i++) {1547 j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);1548 k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);1549 xhdr[j].hic_xheader.xh_cycle_data[k] = *(__be32 *)dp;1550 *(__be32 *)dp = cycle_lsn;1551 dp += BBSIZE;1552 }1553 1554 for (i = 1; i < log->l_iclog_heads; i++)1555 xhdr[i].hic_xheader.xh_cycle = cycle_lsn;1556 }1557}1558 1559/*1560 * Calculate the checksum for a log buffer.1561 *1562 * This is a little more complicated than it should be because the various1563 * headers and the actual data are non-contiguous.1564 */1565__le321566xlog_cksum(1567 struct xlog *log,1568 struct xlog_rec_header *rhead,1569 char *dp,1570 int size)1571{1572 uint32_t crc;1573 1574 /* first generate the crc for the record header ... */1575 crc = xfs_start_cksum_update((char *)rhead,1576 sizeof(struct xlog_rec_header),1577 offsetof(struct xlog_rec_header, h_crc));1578 1579 /* ... then for additional cycle data for v2 logs ... */1580 if (xfs_has_logv2(log->l_mp)) {1581 union xlog_in_core2 *xhdr = (union xlog_in_core2 *)rhead;1582 int i;1583 int xheads;1584 1585 xheads = DIV_ROUND_UP(size, XLOG_HEADER_CYCLE_SIZE);1586 1587 for (i = 1; i < xheads; i++) {1588 crc = crc32c(crc, &xhdr[i].hic_xheader,1589 sizeof(struct xlog_rec_ext_header));1590 }1591 }1592 1593 /* ... and finally for the payload */1594 crc = crc32c(crc, dp, size);1595 1596 return xfs_end_cksum(crc);1597}1598 1599static void1600xlog_bio_end_io(1601 struct bio *bio)1602{1603 struct xlog_in_core *iclog = bio->bi_private;1604 1605 queue_work(iclog->ic_log->l_ioend_workqueue,1606 &iclog->ic_end_io_work);1607}1608 1609static int1610xlog_map_iclog_data(1611 struct bio *bio,1612 void *data,1613 size_t count)1614{1615 do {1616 struct page *page = kmem_to_page(data);1617 unsigned int off = offset_in_page(data);1618 size_t len = min_t(size_t, count, PAGE_SIZE - off);1619 1620 if (bio_add_page(bio, page, len, off) != len)1621 return -EIO;1622 1623 data += len;1624 count -= len;1625 } while (count);1626 1627 return 0;1628}1629 1630STATIC void1631xlog_write_iclog(1632 struct xlog *log,1633 struct xlog_in_core *iclog,1634 uint64_t bno,1635 unsigned int count)1636{1637 ASSERT(bno < log->l_logBBsize);1638 trace_xlog_iclog_write(iclog, _RET_IP_);1639 1640 /*1641 * We lock the iclogbufs here so that we can serialise against I/O1642 * completion during unmount. We might be processing a shutdown1643 * triggered during unmount, and that can occur asynchronously to the1644 * unmount thread, and hence we need to ensure that completes before1645 * tearing down the iclogbufs. Hence we need to hold the buffer lock1646 * across the log IO to archieve that.1647 */1648 down(&iclog->ic_sema);1649 if (xlog_is_shutdown(log)) {1650 /*1651 * It would seem logical to return EIO here, but we rely on1652 * the log state machine to propagate I/O errors instead of1653 * doing it here. We kick of the state machine and unlock1654 * the buffer manually, the code needs to be kept in sync1655 * with the I/O completion path.1656 */1657 goto sync;1658 }1659 1660 /*1661 * We use REQ_SYNC | REQ_IDLE here to tell the block layer the are more1662 * IOs coming immediately after this one. This prevents the block layer1663 * writeback throttle from throttling log writes behind background1664 * metadata writeback and causing priority inversions.1665 */1666 bio_init(&iclog->ic_bio, log->l_targ->bt_bdev, iclog->ic_bvec,1667 howmany(count, PAGE_SIZE),1668 REQ_OP_WRITE | REQ_META | REQ_SYNC | REQ_IDLE);1669 iclog->ic_bio.bi_iter.bi_sector = log->l_logBBstart + bno;1670 iclog->ic_bio.bi_end_io = xlog_bio_end_io;1671 iclog->ic_bio.bi_private = iclog;1672 1673 if (iclog->ic_flags & XLOG_ICL_NEED_FLUSH) {1674 iclog->ic_bio.bi_opf |= REQ_PREFLUSH;1675 /*1676 * For external log devices, we also need to flush the data1677 * device cache first to ensure all metadata writeback covered1678 * by the LSN in this iclog is on stable storage. This is slow,1679 * but it *must* complete before we issue the external log IO.1680 *1681 * If the flush fails, we cannot conclude that past metadata1682 * writeback from the log succeeded. Repeating the flush is1683 * not possible, hence we must shut down with log IO error to1684 * avoid shutdown re-entering this path and erroring out again.1685 */1686 if (log->l_targ != log->l_mp->m_ddev_targp &&1687 blkdev_issue_flush(log->l_mp->m_ddev_targp->bt_bdev))1688 goto shutdown;1689 }1690 if (iclog->ic_flags & XLOG_ICL_NEED_FUA)1691 iclog->ic_bio.bi_opf |= REQ_FUA;1692 1693 iclog->ic_flags &= ~(XLOG_ICL_NEED_FLUSH | XLOG_ICL_NEED_FUA);1694 1695 if (xlog_map_iclog_data(&iclog->ic_bio, iclog->ic_data, count))1696 goto shutdown;1697 1698 if (is_vmalloc_addr(iclog->ic_data))1699 flush_kernel_vmap_range(iclog->ic_data, count);1700 1701 /*1702 * If this log buffer would straddle the end of the log we will have1703 * to split it up into two bios, so that we can continue at the start.1704 */1705 if (bno + BTOBB(count) > log->l_logBBsize) {1706 struct bio *split;1707 1708 split = bio_split(&iclog->ic_bio, log->l_logBBsize - bno,1709 GFP_NOIO, &fs_bio_set);1710 bio_chain(split, &iclog->ic_bio);1711 submit_bio(split);1712 1713 /* restart at logical offset zero for the remainder */1714 iclog->ic_bio.bi_iter.bi_sector = log->l_logBBstart;1715 }1716 1717 submit_bio(&iclog->ic_bio);1718 return;1719shutdown:1720 xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);1721sync:1722 xlog_state_done_syncing(iclog);1723 up(&iclog->ic_sema);1724}1725 1726/*1727 * We need to bump cycle number for the part of the iclog that is1728 * written to the start of the log. Watch out for the header magic1729 * number case, though.1730 */1731static void1732xlog_split_iclog(1733 struct xlog *log,1734 void *data,1735 uint64_t bno,1736 unsigned int count)1737{1738 unsigned int split_offset = BBTOB(log->l_logBBsize - bno);1739 unsigned int i;1740 1741 for (i = split_offset; i < count; i += BBSIZE) {1742 uint32_t cycle = get_unaligned_be32(data + i);1743 1744 if (++cycle == XLOG_HEADER_MAGIC_NUM)1745 cycle++;1746 put_unaligned_be32(cycle, data + i);1747 }1748}1749 1750static int1751xlog_calc_iclog_size(1752 struct xlog *log,1753 struct xlog_in_core *iclog,1754 uint32_t *roundoff)1755{1756 uint32_t count_init, count;1757 1758 /* Add for LR header */1759 count_init = log->l_iclog_hsize + iclog->ic_offset;1760 count = roundup(count_init, log->l_iclog_roundoff);1761 1762 *roundoff = count - count_init;1763 1764 ASSERT(count >= count_init);1765 ASSERT(*roundoff < log->l_iclog_roundoff);1766 return count;1767}1768 1769/*1770 * Flush out the in-core log (iclog) to the on-disk log in an asynchronous1771 * fashion. Previously, we should have moved the current iclog1772 * ptr in the log to point to the next available iclog. This allows further1773 * write to continue while this code syncs out an iclog ready to go.1774 * Before an in-core log can be written out, the data section must be scanned1775 * to save away the 1st word of each BBSIZE block into the header. We replace1776 * it with the current cycle count. Each BBSIZE block is tagged with the1777 * cycle count because there in an implicit assumption that drives will1778 * guarantee that entire 512 byte blocks get written at once. In other words,1779 * we can't have part of a 512 byte block written and part not written. By1780 * tagging each block, we will know which blocks are valid when recovering1781 * after an unclean shutdown.1782 *1783 * This routine is single threaded on the iclog. No other thread can be in1784 * this routine with the same iclog. Changing contents of iclog can there-1785 * fore be done without grabbing the state machine lock. Updating the global1786 * log will require grabbing the lock though.1787 *1788 * The entire log manager uses a logical block numbering scheme. Only1789 * xlog_write_iclog knows about the fact that the log may not start with1790 * block zero on a given device.1791 */1792STATIC void1793xlog_sync(1794 struct xlog *log,1795 struct xlog_in_core *iclog,1796 struct xlog_ticket *ticket)1797{1798 unsigned int count; /* byte count of bwrite */1799 unsigned int roundoff; /* roundoff to BB or stripe */1800 uint64_t bno;1801 unsigned int size;1802 1803 ASSERT(atomic_read(&iclog->ic_refcnt) == 0);1804 trace_xlog_iclog_sync(iclog, _RET_IP_);1805 1806 count = xlog_calc_iclog_size(log, iclog, &roundoff);1807 1808 /*1809 * If we have a ticket, account for the roundoff via the ticket1810 * reservation to avoid touching the hot grant heads needlessly.1811 * Otherwise, we have to move grant heads directly.1812 */1813 if (ticket) {1814 ticket->t_curr_res -= roundoff;1815 } else {1816 xlog_grant_add_space(&log->l_reserve_head, roundoff);1817 xlog_grant_add_space(&log->l_write_head, roundoff);1818 }1819 1820 /* put cycle number in every block */1821 xlog_pack_data(log, iclog, roundoff);1822 1823 /* real byte length */1824 size = iclog->ic_offset;1825 if (xfs_has_logv2(log->l_mp))1826 size += roundoff;1827 iclog->ic_header.h_len = cpu_to_be32(size);1828 1829 XFS_STATS_INC(log->l_mp, xs_log_writes);1830 XFS_STATS_ADD(log->l_mp, xs_log_blocks, BTOBB(count));1831 1832 bno = BLOCK_LSN(be64_to_cpu(iclog->ic_header.h_lsn));1833 1834 /* Do we need to split this write into 2 parts? */1835 if (bno + BTOBB(count) > log->l_logBBsize)1836 xlog_split_iclog(log, &iclog->ic_header, bno, count);1837 1838 /* calculcate the checksum */1839 iclog->ic_header.h_crc = xlog_cksum(log, &iclog->ic_header,1840 iclog->ic_datap, size);1841 /*1842 * Intentionally corrupt the log record CRC based on the error injection1843 * frequency, if defined. This facilitates testing log recovery in the1844 * event of torn writes. Hence, set the IOABORT state to abort the log1845 * write on I/O completion and shutdown the fs. The subsequent mount1846 * detects the bad CRC and attempts to recover.1847 */1848#ifdef DEBUG1849 if (XFS_TEST_ERROR(false, log->l_mp, XFS_ERRTAG_LOG_BAD_CRC)) {1850 iclog->ic_header.h_crc &= cpu_to_le32(0xAAAAAAAA);1851 iclog->ic_fail_crc = true;1852 xfs_warn(log->l_mp,1853 "Intentionally corrupted log record at LSN 0x%llx. Shutdown imminent.",1854 be64_to_cpu(iclog->ic_header.h_lsn));1855 }1856#endif1857 xlog_verify_iclog(log, iclog, count);1858 xlog_write_iclog(log, iclog, bno, count);1859}1860 1861/*1862 * Deallocate a log structure1863 */1864STATIC void1865xlog_dealloc_log(1866 struct xlog *log)1867{1868 xlog_in_core_t *iclog, *next_iclog;1869 int i;1870 1871 /*1872 * Destroy the CIL after waiting for iclog IO completion because an1873 * iclog EIO error will try to shut down the log, which accesses the1874 * CIL to wake up the waiters.1875 */1876 xlog_cil_destroy(log);1877 1878 iclog = log->l_iclog;1879 for (i = 0; i < log->l_iclog_bufs; i++) {1880 next_iclog = iclog->ic_next;1881 kvfree(iclog->ic_data);1882 kfree(iclog);1883 iclog = next_iclog;1884 }1885 1886 log->l_mp->m_log = NULL;1887 destroy_workqueue(log->l_ioend_workqueue);1888 kfree(log);1889}1890 1891/*1892 * Update counters atomically now that memcpy is done.1893 */1894static inline void1895xlog_state_finish_copy(1896 struct xlog *log,1897 struct xlog_in_core *iclog,1898 int record_cnt,1899 int copy_bytes)1900{1901 lockdep_assert_held(&log->l_icloglock);1902 1903 be32_add_cpu(&iclog->ic_header.h_num_logops, record_cnt);1904 iclog->ic_offset += copy_bytes;1905}1906 1907/*1908 * print out info relating to regions written which consume1909 * the reservation1910 */1911void1912xlog_print_tic_res(1913 struct xfs_mount *mp,1914 struct xlog_ticket *ticket)1915{1916 xfs_warn(mp, "ticket reservation summary:");1917 xfs_warn(mp, " unit res = %d bytes", ticket->t_unit_res);1918 xfs_warn(mp, " current res = %d bytes", ticket->t_curr_res);1919 xfs_warn(mp, " original count = %d", ticket->t_ocnt);1920 xfs_warn(mp, " remaining count = %d", ticket->t_cnt);1921}1922 1923/*1924 * Print a summary of the transaction.1925 */1926void1927xlog_print_trans(1928 struct xfs_trans *tp)1929{1930 struct xfs_mount *mp = tp->t_mountp;1931 struct xfs_log_item *lip;1932 1933 /* dump core transaction and ticket info */1934 xfs_warn(mp, "transaction summary:");1935 xfs_warn(mp, " log res = %d", tp->t_log_res);1936 xfs_warn(mp, " log count = %d", tp->t_log_count);1937 xfs_warn(mp, " flags = 0x%x", tp->t_flags);1938 1939 xlog_print_tic_res(mp, tp->t_ticket);1940 1941 /* dump each log item */1942 list_for_each_entry(lip, &tp->t_items, li_trans) {1943 struct xfs_log_vec *lv = lip->li_lv;1944 struct xfs_log_iovec *vec;1945 int i;1946 1947 xfs_warn(mp, "log item: ");1948 xfs_warn(mp, " type = 0x%x", lip->li_type);1949 xfs_warn(mp, " flags = 0x%lx", lip->li_flags);1950 if (!lv)1951 continue;1952 xfs_warn(mp, " niovecs = %d", lv->lv_niovecs);1953 xfs_warn(mp, " size = %d", lv->lv_size);1954 xfs_warn(mp, " bytes = %d", lv->lv_bytes);1955 xfs_warn(mp, " buf len = %d", lv->lv_buf_len);1956 1957 /* dump each iovec for the log item */1958 vec = lv->lv_iovecp;1959 for (i = 0; i < lv->lv_niovecs; i++) {1960 int dumplen = min(vec->i_len, 32);1961 1962 xfs_warn(mp, " iovec[%d]", i);1963 xfs_warn(mp, " type = 0x%x", vec->i_type);1964 xfs_warn(mp, " len = %d", vec->i_len);1965 xfs_warn(mp, " first %d bytes of iovec[%d]:", dumplen, i);1966 xfs_hex_dump(vec->i_addr, dumplen);1967 1968 vec++;1969 }1970 }1971}1972 1973static inline void1974xlog_write_iovec(1975 struct xlog_in_core *iclog,1976 uint32_t *log_offset,1977 void *data,1978 uint32_t write_len,1979 int *bytes_left,1980 uint32_t *record_cnt,1981 uint32_t *data_cnt)1982{1983 ASSERT(*log_offset < iclog->ic_log->l_iclog_size);1984 ASSERT(*log_offset % sizeof(int32_t) == 0);1985 ASSERT(write_len % sizeof(int32_t) == 0);1986 1987 memcpy(iclog->ic_datap + *log_offset, data, write_len);1988 *log_offset += write_len;1989 *bytes_left -= write_len;1990 (*record_cnt)++;1991 *data_cnt += write_len;1992}1993 1994/*1995 * Write log vectors into a single iclog which is guaranteed by the caller1996 * to have enough space to write the entire log vector into.1997 */1998static void1999xlog_write_full(2000 struct xfs_log_vec *lv,2001 struct xlog_ticket *ticket,2002 struct xlog_in_core *iclog,2003 uint32_t *log_offset,2004 uint32_t *len,2005 uint32_t *record_cnt,2006 uint32_t *data_cnt)2007{2008 int index;2009 2010 ASSERT(*log_offset + *len <= iclog->ic_size ||2011 iclog->ic_state == XLOG_STATE_WANT_SYNC);2012 2013 /*2014 * Ordered log vectors have no regions to write so this2015 * loop will naturally skip them.2016 */2017 for (index = 0; index < lv->lv_niovecs; index++) {2018 struct xfs_log_iovec *reg = &lv->lv_iovecp[index];2019 struct xlog_op_header *ophdr = reg->i_addr;2020 2021 ophdr->oh_tid = cpu_to_be32(ticket->t_tid);2022 xlog_write_iovec(iclog, log_offset, reg->i_addr,2023 reg->i_len, len, record_cnt, data_cnt);2024 }2025}2026 2027static int2028xlog_write_get_more_iclog_space(2029 struct xlog_ticket *ticket,2030 struct xlog_in_core **iclogp,2031 uint32_t *log_offset,2032 uint32_t len,2033 uint32_t *record_cnt,2034 uint32_t *data_cnt)2035{2036 struct xlog_in_core *iclog = *iclogp;2037 struct xlog *log = iclog->ic_log;2038 int error;2039 2040 spin_lock(&log->l_icloglock);2041 ASSERT(iclog->ic_state == XLOG_STATE_WANT_SYNC);2042 xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt);2043 error = xlog_state_release_iclog(log, iclog, ticket);2044 spin_unlock(&log->l_icloglock);2045 if (error)2046 return error;2047 2048 error = xlog_state_get_iclog_space(log, len, &iclog, ticket,2049 log_offset);2050 if (error)2051 return error;2052 *record_cnt = 0;2053 *data_cnt = 0;2054 *iclogp = iclog;2055 return 0;2056}2057 2058/*2059 * Write log vectors into a single iclog which is smaller than the current chain2060 * length. We write until we cannot fit a full record into the remaining space2061 * and then stop. We return the log vector that is to be written that cannot2062 * wholly fit in the iclog.2063 */2064static int2065xlog_write_partial(2066 struct xfs_log_vec *lv,2067 struct xlog_ticket *ticket,2068 struct xlog_in_core **iclogp,2069 uint32_t *log_offset,2070 uint32_t *len,2071 uint32_t *record_cnt,2072 uint32_t *data_cnt)2073{2074 struct xlog_in_core *iclog = *iclogp;2075 struct xlog_op_header *ophdr;2076 int index = 0;2077 uint32_t rlen;2078 int error;2079 2080 /* walk the logvec, copying until we run out of space in the iclog */2081 for (index = 0; index < lv->lv_niovecs; index++) {2082 struct xfs_log_iovec *reg = &lv->lv_iovecp[index];2083 uint32_t reg_offset = 0;2084 2085 /*2086 * The first region of a continuation must have a non-zero2087 * length otherwise log recovery will just skip over it and2088 * start recovering from the next opheader it finds. Because we2089 * mark the next opheader as a continuation, recovery will then2090 * incorrectly add the continuation to the previous region and2091 * that breaks stuff.2092 *2093 * Hence if there isn't space for region data after the2094 * opheader, then we need to start afresh with a new iclog.2095 */2096 if (iclog->ic_size - *log_offset <=2097 sizeof(struct xlog_op_header)) {2098 error = xlog_write_get_more_iclog_space(ticket,2099 &iclog, log_offset, *len, record_cnt,2100 data_cnt);2101 if (error)2102 return error;2103 }2104 2105 ophdr = reg->i_addr;2106 rlen = min_t(uint32_t, reg->i_len, iclog->ic_size - *log_offset);2107 2108 ophdr->oh_tid = cpu_to_be32(ticket->t_tid);2109 ophdr->oh_len = cpu_to_be32(rlen - sizeof(struct xlog_op_header));2110 if (rlen != reg->i_len)2111 ophdr->oh_flags |= XLOG_CONTINUE_TRANS;2112 2113 xlog_write_iovec(iclog, log_offset, reg->i_addr,2114 rlen, len, record_cnt, data_cnt);2115 2116 /* If we wrote the whole region, move to the next. */2117 if (rlen == reg->i_len)2118 continue;2119 2120 /*2121 * We now have a partially written iovec, but it can span2122 * multiple iclogs so we loop here. First we release the iclog2123 * we currently have, then we get a new iclog and add a new2124 * opheader. Then we continue copying from where we were until2125 * we either complete the iovec or fill the iclog. If we2126 * complete the iovec, then we increment the index and go right2127 * back to the top of the outer loop. if we fill the iclog, we2128 * run the inner loop again.2129 *2130 * This is complicated by the tail of a region using all the2131 * space in an iclog and hence requiring us to release the iclog2132 * and get a new one before returning to the outer loop. We must2133 * always guarantee that we exit this inner loop with at least2134 * space for log transaction opheaders left in the current2135 * iclog, hence we cannot just terminate the loop at the end2136 * of the of the continuation. So we loop while there is no2137 * space left in the current iclog, and check for the end of the2138 * continuation after getting a new iclog.2139 */2140 do {2141 /*2142 * Ensure we include the continuation opheader in the2143 * space we need in the new iclog by adding that size2144 * to the length we require. This continuation opheader2145 * needs to be accounted to the ticket as the space it2146 * consumes hasn't been accounted to the lv we are2147 * writing.2148 */2149 error = xlog_write_get_more_iclog_space(ticket,2150 &iclog, log_offset,2151 *len + sizeof(struct xlog_op_header),2152 record_cnt, data_cnt);2153 if (error)2154 return error;2155 2156 ophdr = iclog->ic_datap + *log_offset;2157 ophdr->oh_tid = cpu_to_be32(ticket->t_tid);2158 ophdr->oh_clientid = XFS_TRANSACTION;2159 ophdr->oh_res2 = 0;2160 ophdr->oh_flags = XLOG_WAS_CONT_TRANS;2161 2162 ticket->t_curr_res -= sizeof(struct xlog_op_header);2163 *log_offset += sizeof(struct xlog_op_header);2164 *data_cnt += sizeof(struct xlog_op_header);2165 2166 /*2167 * If rlen fits in the iclog, then end the region2168 * continuation. Otherwise we're going around again.2169 */2170 reg_offset += rlen;2171 rlen = reg->i_len - reg_offset;2172 if (rlen <= iclog->ic_size - *log_offset)2173 ophdr->oh_flags |= XLOG_END_TRANS;2174 else2175 ophdr->oh_flags |= XLOG_CONTINUE_TRANS;2176 2177 rlen = min_t(uint32_t, rlen, iclog->ic_size - *log_offset);2178 ophdr->oh_len = cpu_to_be32(rlen);2179 2180 xlog_write_iovec(iclog, log_offset,2181 reg->i_addr + reg_offset,2182 rlen, len, record_cnt, data_cnt);2183 2184 } while (ophdr->oh_flags & XLOG_CONTINUE_TRANS);2185 }2186 2187 /*2188 * No more iovecs remain in this logvec so return the next log vec to2189 * the caller so it can go back to fast path copying.2190 */2191 *iclogp = iclog;2192 return 0;2193}2194 2195/*2196 * Write some region out to in-core log2197 *2198 * This will be called when writing externally provided regions or when2199 * writing out a commit record for a given transaction.2200 *2201 * General algorithm:2202 * 1. Find total length of this write. This may include adding to the2203 * lengths passed in.2204 * 2. Check whether we violate the tickets reservation.2205 * 3. While writing to this iclog2206 * A. Reserve as much space in this iclog as can get2207 * B. If this is first write, save away start lsn2208 * C. While writing this region:2209 * 1. If first write of transaction, write start record2210 * 2. Write log operation header (header per region)2211 * 3. Find out if we can fit entire region into this iclog2212 * 4. Potentially, verify destination memcpy ptr2213 * 5. Memcpy (partial) region2214 * 6. If partial copy, release iclog; otherwise, continue2215 * copying more regions into current iclog2216 * 4. Mark want sync bit (in simulation mode)2217 * 5. Release iclog for potential flush to on-disk log.2218 *2219 * ERRORS:2220 * 1. Panic if reservation is overrun. This should never happen since2221 * reservation amounts are generated internal to the filesystem.2222 * NOTES:2223 * 1. Tickets are single threaded data structures.2224 * 2. The XLOG_END_TRANS & XLOG_CONTINUE_TRANS flags are passed down to the2225 * syncing routine. When a single log_write region needs to span2226 * multiple in-core logs, the XLOG_CONTINUE_TRANS bit should be set2227 * on all log operation writes which don't contain the end of the2228 * region. The XLOG_END_TRANS bit is used for the in-core log2229 * operation which contains the end of the continued log_write region.2230 * 3. When xlog_state_get_iclog_space() grabs the rest of the current iclog,2231 * we don't really know exactly how much space will be used. As a result,2232 * we don't update ic_offset until the end when we know exactly how many2233 * bytes have been written out.2234 */2235int2236xlog_write(2237 struct xlog *log,2238 struct xfs_cil_ctx *ctx,2239 struct list_head *lv_chain,2240 struct xlog_ticket *ticket,2241 uint32_t len)2242 2243{2244 struct xlog_in_core *iclog = NULL;2245 struct xfs_log_vec *lv;2246 uint32_t record_cnt = 0;2247 uint32_t data_cnt = 0;2248 int error = 0;2249 int log_offset;2250 2251 if (ticket->t_curr_res < 0) {2252 xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES,2253 "ctx ticket reservation ran out. Need to up reservation");2254 xlog_print_tic_res(log->l_mp, ticket);2255 xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);2256 }2257 2258 error = xlog_state_get_iclog_space(log, len, &iclog, ticket,2259 &log_offset);2260 if (error)2261 return error;2262 2263 ASSERT(log_offset <= iclog->ic_size - 1);2264 2265 /*2266 * If we have a context pointer, pass it the first iclog we are2267 * writing to so it can record state needed for iclog write2268 * ordering.2269 */2270 if (ctx)2271 xlog_cil_set_ctx_write_state(ctx, iclog);2272 2273 list_for_each_entry(lv, lv_chain, lv_list) {2274 /*2275 * If the entire log vec does not fit in the iclog, punt it to2276 * the partial copy loop which can handle this case.2277 */2278 if (lv->lv_niovecs &&2279 lv->lv_bytes > iclog->ic_size - log_offset) {2280 error = xlog_write_partial(lv, ticket, &iclog,2281 &log_offset, &len, &record_cnt,2282 &data_cnt);2283 if (error) {2284 /*2285 * We have no iclog to release, so just return2286 * the error immediately.2287 */2288 return error;2289 }2290 } else {2291 xlog_write_full(lv, ticket, iclog, &log_offset,2292 &len, &record_cnt, &data_cnt);2293 }2294 }2295 ASSERT(len == 0);2296 2297 /*2298 * We've already been guaranteed that the last writes will fit inside2299 * the current iclog, and hence it will already have the space used by2300 * those writes accounted to it. Hence we do not need to update the2301 * iclog with the number of bytes written here.2302 */2303 spin_lock(&log->l_icloglock);2304 xlog_state_finish_copy(log, iclog, record_cnt, 0);2305 error = xlog_state_release_iclog(log, iclog, ticket);2306 spin_unlock(&log->l_icloglock);2307 2308 return error;2309}2310 2311static void2312xlog_state_activate_iclog(2313 struct xlog_in_core *iclog,2314 int *iclogs_changed)2315{2316 ASSERT(list_empty_careful(&iclog->ic_callbacks));2317 trace_xlog_iclog_activate(iclog, _RET_IP_);2318 2319 /*2320 * If the number of ops in this iclog indicate it just contains the2321 * dummy transaction, we can change state into IDLE (the second time2322 * around). Otherwise we should change the state into NEED a dummy.2323 * We don't need to cover the dummy.2324 */2325 if (*iclogs_changed == 0 &&2326 iclog->ic_header.h_num_logops == cpu_to_be32(XLOG_COVER_OPS)) {2327 *iclogs_changed = 1;2328 } else {2329 /*2330 * We have two dirty iclogs so start over. This could also be2331 * num of ops indicating this is not the dummy going out.2332 */2333 *iclogs_changed = 2;2334 }2335 2336 iclog->ic_state = XLOG_STATE_ACTIVE;2337 iclog->ic_offset = 0;2338 iclog->ic_header.h_num_logops = 0;2339 memset(iclog->ic_header.h_cycle_data, 0,2340 sizeof(iclog->ic_header.h_cycle_data));2341 iclog->ic_header.h_lsn = 0;2342 iclog->ic_header.h_tail_lsn = 0;2343}2344 2345/*2346 * Loop through all iclogs and mark all iclogs currently marked DIRTY as2347 * ACTIVE after iclog I/O has completed.2348 */2349static void2350xlog_state_activate_iclogs(2351 struct xlog *log,2352 int *iclogs_changed)2353{2354 struct xlog_in_core *iclog = log->l_iclog;2355 2356 do {2357 if (iclog->ic_state == XLOG_STATE_DIRTY)2358 xlog_state_activate_iclog(iclog, iclogs_changed);2359 /*2360 * The ordering of marking iclogs ACTIVE must be maintained, so2361 * an iclog doesn't become ACTIVE beyond one that is SYNCING.2362 */2363 else if (iclog->ic_state != XLOG_STATE_ACTIVE)2364 break;2365 } while ((iclog = iclog->ic_next) != log->l_iclog);2366}2367 2368static int2369xlog_covered_state(2370 int prev_state,2371 int iclogs_changed)2372{2373 /*2374 * We go to NEED for any non-covering writes. We go to NEED2 if we just2375 * wrote the first covering record (DONE). We go to IDLE if we just2376 * wrote the second covering record (DONE2) and remain in IDLE until a2377 * non-covering write occurs.2378 */2379 switch (prev_state) {2380 case XLOG_STATE_COVER_IDLE:2381 if (iclogs_changed == 1)2382 return XLOG_STATE_COVER_IDLE;2383 fallthrough;2384 case XLOG_STATE_COVER_NEED:2385 case XLOG_STATE_COVER_NEED2:2386 break;2387 case XLOG_STATE_COVER_DONE:2388 if (iclogs_changed == 1)2389 return XLOG_STATE_COVER_NEED2;2390 break;2391 case XLOG_STATE_COVER_DONE2:2392 if (iclogs_changed == 1)2393 return XLOG_STATE_COVER_IDLE;2394 break;2395 default:2396 ASSERT(0);2397 }2398 2399 return XLOG_STATE_COVER_NEED;2400}2401 2402STATIC void2403xlog_state_clean_iclog(2404 struct xlog *log,2405 struct xlog_in_core *dirty_iclog)2406{2407 int iclogs_changed = 0;2408 2409 trace_xlog_iclog_clean(dirty_iclog, _RET_IP_);2410 2411 dirty_iclog->ic_state = XLOG_STATE_DIRTY;2412 2413 xlog_state_activate_iclogs(log, &iclogs_changed);2414 wake_up_all(&dirty_iclog->ic_force_wait);2415 2416 if (iclogs_changed) {2417 log->l_covered_state = xlog_covered_state(log->l_covered_state,2418 iclogs_changed);2419 }2420}2421 2422STATIC xfs_lsn_t2423xlog_get_lowest_lsn(2424 struct xlog *log)2425{2426 struct xlog_in_core *iclog = log->l_iclog;2427 xfs_lsn_t lowest_lsn = 0, lsn;2428 2429 do {2430 if (iclog->ic_state == XLOG_STATE_ACTIVE ||2431 iclog->ic_state == XLOG_STATE_DIRTY)2432 continue;2433 2434 lsn = be64_to_cpu(iclog->ic_header.h_lsn);2435 if ((lsn && !lowest_lsn) || XFS_LSN_CMP(lsn, lowest_lsn) < 0)2436 lowest_lsn = lsn;2437 } while ((iclog = iclog->ic_next) != log->l_iclog);2438 2439 return lowest_lsn;2440}2441 2442/*2443 * Return true if we need to stop processing, false to continue to the next2444 * iclog. The caller will need to run callbacks if the iclog is returned in the2445 * XLOG_STATE_CALLBACK state.2446 */2447static bool2448xlog_state_iodone_process_iclog(2449 struct xlog *log,2450 struct xlog_in_core *iclog)2451{2452 xfs_lsn_t lowest_lsn;2453 xfs_lsn_t header_lsn;2454 2455 switch (iclog->ic_state) {2456 case XLOG_STATE_ACTIVE:2457 case XLOG_STATE_DIRTY:2458 /*2459 * Skip all iclogs in the ACTIVE & DIRTY states:2460 */2461 return false;2462 case XLOG_STATE_DONE_SYNC:2463 /*2464 * Now that we have an iclog that is in the DONE_SYNC state, do2465 * one more check here to see if we have chased our tail around.2466 * If this is not the lowest lsn iclog, then we will leave it2467 * for another completion to process.2468 */2469 header_lsn = be64_to_cpu(iclog->ic_header.h_lsn);2470 lowest_lsn = xlog_get_lowest_lsn(log);2471 if (lowest_lsn && XFS_LSN_CMP(lowest_lsn, header_lsn) < 0)2472 return false;2473 /*2474 * If there are no callbacks on this iclog, we can mark it clean2475 * immediately and return. Otherwise we need to run the2476 * callbacks.2477 */2478 if (list_empty(&iclog->ic_callbacks)) {2479 xlog_state_clean_iclog(log, iclog);2480 return false;2481 }2482 trace_xlog_iclog_callback(iclog, _RET_IP_);2483 iclog->ic_state = XLOG_STATE_CALLBACK;2484 return false;2485 default:2486 /*2487 * Can only perform callbacks in order. Since this iclog is not2488 * in the DONE_SYNC state, we skip the rest and just try to2489 * clean up.2490 */2491 return true;2492 }2493}2494 2495/*2496 * Loop over all the iclogs, running attached callbacks on them. Return true if2497 * we ran any callbacks, indicating that we dropped the icloglock. We don't need2498 * to handle transient shutdown state here at all because2499 * xlog_state_shutdown_callbacks() will be run to do the necessary shutdown2500 * cleanup of the callbacks.2501 */2502static bool2503xlog_state_do_iclog_callbacks(2504 struct xlog *log)2505 __releases(&log->l_icloglock)2506 __acquires(&log->l_icloglock)2507{2508 struct xlog_in_core *first_iclog = log->l_iclog;2509 struct xlog_in_core *iclog = first_iclog;2510 bool ran_callback = false;2511 2512 do {2513 LIST_HEAD(cb_list);2514 2515 if (xlog_state_iodone_process_iclog(log, iclog))2516 break;2517 if (iclog->ic_state != XLOG_STATE_CALLBACK) {2518 iclog = iclog->ic_next;2519 continue;2520 }2521 list_splice_init(&iclog->ic_callbacks, &cb_list);2522 spin_unlock(&log->l_icloglock);2523 2524 trace_xlog_iclog_callbacks_start(iclog, _RET_IP_);2525 xlog_cil_process_committed(&cb_list);2526 trace_xlog_iclog_callbacks_done(iclog, _RET_IP_);2527 ran_callback = true;2528 2529 spin_lock(&log->l_icloglock);2530 xlog_state_clean_iclog(log, iclog);2531 iclog = iclog->ic_next;2532 } while (iclog != first_iclog);2533 2534 return ran_callback;2535}2536 2537 2538/*2539 * Loop running iclog completion callbacks until there are no more iclogs in a2540 * state that can run callbacks.2541 */2542STATIC void2543xlog_state_do_callback(2544 struct xlog *log)2545{2546 int flushcnt = 0;2547 int repeats = 0;2548 2549 spin_lock(&log->l_icloglock);2550 while (xlog_state_do_iclog_callbacks(log)) {2551 if (xlog_is_shutdown(log))2552 break;2553 2554 if (++repeats > 5000) {2555 flushcnt += repeats;2556 repeats = 0;2557 xfs_warn(log->l_mp,2558 "%s: possible infinite loop (%d iterations)",2559 __func__, flushcnt);2560 }2561 }2562 2563 if (log->l_iclog->ic_state == XLOG_STATE_ACTIVE)2564 wake_up_all(&log->l_flush_wait);2565 2566 spin_unlock(&log->l_icloglock);2567}2568 2569 2570/*2571 * Finish transitioning this iclog to the dirty state.2572 *2573 * Callbacks could take time, so they are done outside the scope of the2574 * global state machine log lock.2575 */2576STATIC void2577xlog_state_done_syncing(2578 struct xlog_in_core *iclog)2579{2580 struct xlog *log = iclog->ic_log;2581 2582 spin_lock(&log->l_icloglock);2583 ASSERT(atomic_read(&iclog->ic_refcnt) == 0);2584 trace_xlog_iclog_sync_done(iclog, _RET_IP_);2585 2586 /*2587 * If we got an error, either on the first buffer, or in the case of2588 * split log writes, on the second, we shut down the file system and2589 * no iclogs should ever be attempted to be written to disk again.2590 */2591 if (!xlog_is_shutdown(log)) {2592 ASSERT(iclog->ic_state == XLOG_STATE_SYNCING);2593 iclog->ic_state = XLOG_STATE_DONE_SYNC;2594 }2595 2596 /*2597 * Someone could be sleeping prior to writing out the next2598 * iclog buffer, we wake them all, one will get to do the2599 * I/O, the others get to wait for the result.2600 */2601 wake_up_all(&iclog->ic_write_wait);2602 spin_unlock(&log->l_icloglock);2603 xlog_state_do_callback(log);2604}2605 2606/*2607 * If the head of the in-core log ring is not (ACTIVE or DIRTY), then we must2608 * sleep. We wait on the flush queue on the head iclog as that should be2609 * the first iclog to complete flushing. Hence if all iclogs are syncing,2610 * we will wait here and all new writes will sleep until a sync completes.2611 *2612 * The in-core logs are used in a circular fashion. They are not used2613 * out-of-order even when an iclog past the head is free.2614 *2615 * return:2616 * * log_offset where xlog_write() can start writing into the in-core2617 * log's data space.2618 * * in-core log pointer to which xlog_write() should write.2619 * * boolean indicating this is a continued write to an in-core log.2620 * If this is the last write, then the in-core log's offset field2621 * needs to be incremented, depending on the amount of data which2622 * is copied.2623 */2624STATIC int2625xlog_state_get_iclog_space(2626 struct xlog *log,2627 int len,2628 struct xlog_in_core **iclogp,2629 struct xlog_ticket *ticket,2630 int *logoffsetp)2631{2632 int log_offset;2633 xlog_rec_header_t *head;2634 xlog_in_core_t *iclog;2635 2636restart:2637 spin_lock(&log->l_icloglock);2638 if (xlog_is_shutdown(log)) {2639 spin_unlock(&log->l_icloglock);2640 return -EIO;2641 }2642 2643 iclog = log->l_iclog;2644 if (iclog->ic_state != XLOG_STATE_ACTIVE) {2645 XFS_STATS_INC(log->l_mp, xs_log_noiclogs);2646 2647 /* Wait for log writes to have flushed */2648 xlog_wait(&log->l_flush_wait, &log->l_icloglock);2649 goto restart;2650 }2651 2652 head = &iclog->ic_header;2653 2654 atomic_inc(&iclog->ic_refcnt); /* prevents sync */2655 log_offset = iclog->ic_offset;2656 2657 trace_xlog_iclog_get_space(iclog, _RET_IP_);2658 2659 /* On the 1st write to an iclog, figure out lsn. This works2660 * if iclogs marked XLOG_STATE_WANT_SYNC always write out what they are2661 * committing to. If the offset is set, that's how many blocks2662 * must be written.2663 */2664 if (log_offset == 0) {2665 ticket->t_curr_res -= log->l_iclog_hsize;2666 head->h_cycle = cpu_to_be32(log->l_curr_cycle);2667 head->h_lsn = cpu_to_be64(2668 xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block));2669 ASSERT(log->l_curr_block >= 0);2670 }2671 2672 /* If there is enough room to write everything, then do it. Otherwise,2673 * claim the rest of the region and make sure the XLOG_STATE_WANT_SYNC2674 * bit is on, so this will get flushed out. Don't update ic_offset2675 * until you know exactly how many bytes get copied. Therefore, wait2676 * until later to update ic_offset.2677 *2678 * xlog_write() algorithm assumes that at least 2 xlog_op_header_t's2679 * can fit into remaining data section.2680 */2681 if (iclog->ic_size - iclog->ic_offset < 2*sizeof(xlog_op_header_t)) {2682 int error = 0;2683 2684 xlog_state_switch_iclogs(log, iclog, iclog->ic_size);2685 2686 /*2687 * If we are the only one writing to this iclog, sync it to2688 * disk. We need to do an atomic compare and decrement here to2689 * avoid racing with concurrent atomic_dec_and_lock() calls in2690 * xlog_state_release_iclog() when there is more than one2691 * reference to the iclog.2692 */2693 if (!atomic_add_unless(&iclog->ic_refcnt, -1, 1))2694 error = xlog_state_release_iclog(log, iclog, ticket);2695 spin_unlock(&log->l_icloglock);2696 if (error)2697 return error;2698 goto restart;2699 }2700 2701 /* Do we have enough room to write the full amount in the remainder2702 * of this iclog? Or must we continue a write on the next iclog and2703 * mark this iclog as completely taken? In the case where we switch2704 * iclogs (to mark it taken), this particular iclog will release/sync2705 * to disk in xlog_write().2706 */2707 if (len <= iclog->ic_size - iclog->ic_offset)2708 iclog->ic_offset += len;2709 else2710 xlog_state_switch_iclogs(log, iclog, iclog->ic_size);2711 *iclogp = iclog;2712 2713 ASSERT(iclog->ic_offset <= iclog->ic_size);2714 spin_unlock(&log->l_icloglock);2715 2716 *logoffsetp = log_offset;2717 return 0;2718}2719 2720/*2721 * The first cnt-1 times a ticket goes through here we don't need to move the2722 * grant write head because the permanent reservation has reserved cnt times the2723 * unit amount. Release part of current permanent unit reservation and reset2724 * current reservation to be one units worth. Also move grant reservation head2725 * forward.2726 */2727void2728xfs_log_ticket_regrant(2729 struct xlog *log,2730 struct xlog_ticket *ticket)2731{2732 trace_xfs_log_ticket_regrant(log, ticket);2733 2734 if (ticket->t_cnt > 0)2735 ticket->t_cnt--;2736 2737 xlog_grant_sub_space(&log->l_reserve_head, ticket->t_curr_res);2738 xlog_grant_sub_space(&log->l_write_head, ticket->t_curr_res);2739 ticket->t_curr_res = ticket->t_unit_res;2740 2741 trace_xfs_log_ticket_regrant_sub(log, ticket);2742 2743 /* just return if we still have some of the pre-reserved space */2744 if (!ticket->t_cnt) {2745 xlog_grant_add_space(&log->l_reserve_head, ticket->t_unit_res);2746 trace_xfs_log_ticket_regrant_exit(log, ticket);2747 2748 ticket->t_curr_res = ticket->t_unit_res;2749 }2750 2751 xfs_log_ticket_put(ticket);2752}2753 2754/*2755 * Give back the space left from a reservation.2756 *2757 * All the information we need to make a correct determination of space left2758 * is present. For non-permanent reservations, things are quite easy. The2759 * count should have been decremented to zero. We only need to deal with the2760 * space remaining in the current reservation part of the ticket. If the2761 * ticket contains a permanent reservation, there may be left over space which2762 * needs to be released. A count of N means that N-1 refills of the current2763 * reservation can be done before we need to ask for more space. The first2764 * one goes to fill up the first current reservation. Once we run out of2765 * space, the count will stay at zero and the only space remaining will be2766 * in the current reservation field.2767 */2768void2769xfs_log_ticket_ungrant(2770 struct xlog *log,2771 struct xlog_ticket *ticket)2772{2773 int bytes;2774 2775 trace_xfs_log_ticket_ungrant(log, ticket);2776 2777 if (ticket->t_cnt > 0)2778 ticket->t_cnt--;2779 2780 trace_xfs_log_ticket_ungrant_sub(log, ticket);2781 2782 /*2783 * If this is a permanent reservation ticket, we may be able to free2784 * up more space based on the remaining count.2785 */2786 bytes = ticket->t_curr_res;2787 if (ticket->t_cnt > 0) {2788 ASSERT(ticket->t_flags & XLOG_TIC_PERM_RESERV);2789 bytes += ticket->t_unit_res*ticket->t_cnt;2790 }2791 2792 xlog_grant_sub_space(&log->l_reserve_head, bytes);2793 xlog_grant_sub_space(&log->l_write_head, bytes);2794 2795 trace_xfs_log_ticket_ungrant_exit(log, ticket);2796 2797 xfs_log_space_wake(log->l_mp);2798 xfs_log_ticket_put(ticket);2799}2800 2801/*2802 * This routine will mark the current iclog in the ring as WANT_SYNC and move2803 * the current iclog pointer to the next iclog in the ring.2804 */2805void2806xlog_state_switch_iclogs(2807 struct xlog *log,2808 struct xlog_in_core *iclog,2809 int eventual_size)2810{2811 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);2812 assert_spin_locked(&log->l_icloglock);2813 trace_xlog_iclog_switch(iclog, _RET_IP_);2814 2815 if (!eventual_size)2816 eventual_size = iclog->ic_offset;2817 iclog->ic_state = XLOG_STATE_WANT_SYNC;2818 iclog->ic_header.h_prev_block = cpu_to_be32(log->l_prev_block);2819 log->l_prev_block = log->l_curr_block;2820 log->l_prev_cycle = log->l_curr_cycle;2821 2822 /* roll log?: ic_offset changed later */2823 log->l_curr_block += BTOBB(eventual_size)+BTOBB(log->l_iclog_hsize);2824 2825 /* Round up to next log-sunit */2826 if (log->l_iclog_roundoff > BBSIZE) {2827 uint32_t sunit_bb = BTOBB(log->l_iclog_roundoff);2828 log->l_curr_block = roundup(log->l_curr_block, sunit_bb);2829 }2830 2831 if (log->l_curr_block >= log->l_logBBsize) {2832 /*2833 * Rewind the current block before the cycle is bumped to make2834 * sure that the combined LSN never transiently moves forward2835 * when the log wraps to the next cycle. This is to support the2836 * unlocked sample of these fields from xlog_valid_lsn(). Most2837 * other cases should acquire l_icloglock.2838 */2839 log->l_curr_block -= log->l_logBBsize;2840 ASSERT(log->l_curr_block >= 0);2841 smp_wmb();2842 log->l_curr_cycle++;2843 if (log->l_curr_cycle == XLOG_HEADER_MAGIC_NUM)2844 log->l_curr_cycle++;2845 }2846 ASSERT(iclog == log->l_iclog);2847 log->l_iclog = iclog->ic_next;2848}2849 2850/*2851 * Force the iclog to disk and check if the iclog has been completed before2852 * xlog_force_iclog() returns. This can happen on synchronous (e.g.2853 * pmem) or fast async storage because we drop the icloglock to issue the IO.2854 * If completion has already occurred, tell the caller so that it can avoid an2855 * unnecessary wait on the iclog.2856 */2857static int2858xlog_force_and_check_iclog(2859 struct xlog_in_core *iclog,2860 bool *completed)2861{2862 xfs_lsn_t lsn = be64_to_cpu(iclog->ic_header.h_lsn);2863 int error;2864 2865 *completed = false;2866 error = xlog_force_iclog(iclog);2867 if (error)2868 return error;2869 2870 /*2871 * If the iclog has already been completed and reused the header LSN2872 * will have been rewritten by completion2873 */2874 if (be64_to_cpu(iclog->ic_header.h_lsn) != lsn)2875 *completed = true;2876 return 0;2877}2878 2879/*2880 * Write out all data in the in-core log as of this exact moment in time.2881 *2882 * Data may be written to the in-core log during this call. However,2883 * we don't guarantee this data will be written out. A change from past2884 * implementation means this routine will *not* write out zero length LRs.2885 *2886 * Basically, we try and perform an intelligent scan of the in-core logs.2887 * If we determine there is no flushable data, we just return. There is no2888 * flushable data if:2889 *2890 * 1. the current iclog is active and has no data; the previous iclog2891 * is in the active or dirty state.2892 * 2. the current iclog is drity, and the previous iclog is in the2893 * active or dirty state.2894 *2895 * We may sleep if:2896 *2897 * 1. the current iclog is not in the active nor dirty state.2898 * 2. the current iclog dirty, and the previous iclog is not in the2899 * active nor dirty state.2900 * 3. the current iclog is active, and there is another thread writing2901 * to this particular iclog.2902 * 4. a) the current iclog is active and has no other writers2903 * b) when we return from flushing out this iclog, it is still2904 * not in the active nor dirty state.2905 */2906int2907xfs_log_force(2908 struct xfs_mount *mp,2909 uint flags)2910{2911 struct xlog *log = mp->m_log;2912 struct xlog_in_core *iclog;2913 2914 XFS_STATS_INC(mp, xs_log_force);2915 trace_xfs_log_force(mp, 0, _RET_IP_);2916 2917 xlog_cil_force(log);2918 2919 spin_lock(&log->l_icloglock);2920 if (xlog_is_shutdown(log))2921 goto out_error;2922 2923 iclog = log->l_iclog;2924 trace_xlog_iclog_force(iclog, _RET_IP_);2925 2926 if (iclog->ic_state == XLOG_STATE_DIRTY ||2927 (iclog->ic_state == XLOG_STATE_ACTIVE &&2928 atomic_read(&iclog->ic_refcnt) == 0 && iclog->ic_offset == 0)) {2929 /*2930 * If the head is dirty or (active and empty), then we need to2931 * look at the previous iclog.2932 *2933 * If the previous iclog is active or dirty we are done. There2934 * is nothing to sync out. Otherwise, we attach ourselves to the2935 * previous iclog and go to sleep.2936 */2937 iclog = iclog->ic_prev;2938 } else if (iclog->ic_state == XLOG_STATE_ACTIVE) {2939 if (atomic_read(&iclog->ic_refcnt) == 0) {2940 /* We have exclusive access to this iclog. */2941 bool completed;2942 2943 if (xlog_force_and_check_iclog(iclog, &completed))2944 goto out_error;2945 2946 if (completed)2947 goto out_unlock;2948 } else {2949 /*2950 * Someone else is still writing to this iclog, so we2951 * need to ensure that when they release the iclog it2952 * gets synced immediately as we may be waiting on it.2953 */2954 xlog_state_switch_iclogs(log, iclog, 0);2955 }2956 }2957 2958 /*2959 * The iclog we are about to wait on may contain the checkpoint pushed2960 * by the above xlog_cil_force() call, but it may not have been pushed2961 * to disk yet. Like the ACTIVE case above, we need to make sure caches2962 * are flushed when this iclog is written.2963 */2964 if (iclog->ic_state == XLOG_STATE_WANT_SYNC)2965 iclog->ic_flags |= XLOG_ICL_NEED_FLUSH | XLOG_ICL_NEED_FUA;2966 2967 if (flags & XFS_LOG_SYNC)2968 return xlog_wait_on_iclog(iclog);2969out_unlock:2970 spin_unlock(&log->l_icloglock);2971 return 0;2972out_error:2973 spin_unlock(&log->l_icloglock);2974 return -EIO;2975}2976 2977/*2978 * Force the log to a specific LSN.2979 *2980 * If an iclog with that lsn can be found:2981 * If it is in the DIRTY state, just return.2982 * If it is in the ACTIVE state, move the in-core log into the WANT_SYNC2983 * state and go to sleep or return.2984 * If it is in any other state, go to sleep or return.2985 *2986 * Synchronous forces are implemented with a wait queue. All callers trying2987 * to force a given lsn to disk must wait on the queue attached to the2988 * specific in-core log. When given in-core log finally completes its write2989 * to disk, that thread will wake up all threads waiting on the queue.2990 */2991static int2992xlog_force_lsn(2993 struct xlog *log,2994 xfs_lsn_t lsn,2995 uint flags,2996 int *log_flushed,2997 bool already_slept)2998{2999 struct xlog_in_core *iclog;3000 bool completed;3001 3002 spin_lock(&log->l_icloglock);3003 if (xlog_is_shutdown(log))3004 goto out_error;3005 3006 iclog = log->l_iclog;3007 while (be64_to_cpu(iclog->ic_header.h_lsn) != lsn) {3008 trace_xlog_iclog_force_lsn(iclog, _RET_IP_);3009 iclog = iclog->ic_next;3010 if (iclog == log->l_iclog)3011 goto out_unlock;3012 }3013 3014 switch (iclog->ic_state) {3015 case XLOG_STATE_ACTIVE:3016 /*3017 * We sleep here if we haven't already slept (e.g. this is the3018 * first time we've looked at the correct iclog buf) and the3019 * buffer before us is going to be sync'ed. The reason for this3020 * is that if we are doing sync transactions here, by waiting3021 * for the previous I/O to complete, we can allow a few more3022 * transactions into this iclog before we close it down.3023 *3024 * Otherwise, we mark the buffer WANT_SYNC, and bump up the3025 * refcnt so we can release the log (which drops the ref count).3026 * The state switch keeps new transaction commits from using3027 * this buffer. When the current commits finish writing into3028 * the buffer, the refcount will drop to zero and the buffer3029 * will go out then.3030 */3031 if (!already_slept &&3032 (iclog->ic_prev->ic_state == XLOG_STATE_WANT_SYNC ||3033 iclog->ic_prev->ic_state == XLOG_STATE_SYNCING)) {3034 xlog_wait(&iclog->ic_prev->ic_write_wait,3035 &log->l_icloglock);3036 return -EAGAIN;3037 }3038 if (xlog_force_and_check_iclog(iclog, &completed))3039 goto out_error;3040 if (log_flushed)3041 *log_flushed = 1;3042 if (completed)3043 goto out_unlock;3044 break;3045 case XLOG_STATE_WANT_SYNC:3046 /*3047 * This iclog may contain the checkpoint pushed by the3048 * xlog_cil_force_seq() call, but there are other writers still3049 * accessing it so it hasn't been pushed to disk yet. Like the3050 * ACTIVE case above, we need to make sure caches are flushed3051 * when this iclog is written.3052 */3053 iclog->ic_flags |= XLOG_ICL_NEED_FLUSH | XLOG_ICL_NEED_FUA;3054 break;3055 default:3056 /*3057 * The entire checkpoint was written by the CIL force and is on3058 * its way to disk already. It will be stable when it3059 * completes, so we don't need to manipulate caches here at all.3060 * We just need to wait for completion if necessary.3061 */3062 break;3063 }3064 3065 if (flags & XFS_LOG_SYNC)3066 return xlog_wait_on_iclog(iclog);3067out_unlock:3068 spin_unlock(&log->l_icloglock);3069 return 0;3070out_error:3071 spin_unlock(&log->l_icloglock);3072 return -EIO;3073}3074 3075/*3076 * Force the log to a specific checkpoint sequence.3077 *3078 * First force the CIL so that all the required changes have been flushed to the3079 * iclogs. If the CIL force completed it will return a commit LSN that indicates3080 * the iclog that needs to be flushed to stable storage. If the caller needs3081 * a synchronous log force, we will wait on the iclog with the LSN returned by3082 * xlog_cil_force_seq() to be completed.3083 */3084int3085xfs_log_force_seq(3086 struct xfs_mount *mp,3087 xfs_csn_t seq,3088 uint flags,3089 int *log_flushed)3090{3091 struct xlog *log = mp->m_log;3092 xfs_lsn_t lsn;3093 int ret;3094 ASSERT(seq != 0);3095 3096 XFS_STATS_INC(mp, xs_log_force);3097 trace_xfs_log_force(mp, seq, _RET_IP_);3098 3099 lsn = xlog_cil_force_seq(log, seq);3100 if (lsn == NULLCOMMITLSN)3101 return 0;3102 3103 ret = xlog_force_lsn(log, lsn, flags, log_flushed, false);3104 if (ret == -EAGAIN) {3105 XFS_STATS_INC(mp, xs_log_force_sleep);3106 ret = xlog_force_lsn(log, lsn, flags, log_flushed, true);3107 }3108 return ret;3109}3110 3111/*3112 * Free a used ticket when its refcount falls to zero.3113 */3114void3115xfs_log_ticket_put(3116 xlog_ticket_t *ticket)3117{3118 ASSERT(atomic_read(&ticket->t_ref) > 0);3119 if (atomic_dec_and_test(&ticket->t_ref))3120 kmem_cache_free(xfs_log_ticket_cache, ticket);3121}3122 3123xlog_ticket_t *3124xfs_log_ticket_get(3125 xlog_ticket_t *ticket)3126{3127 ASSERT(atomic_read(&ticket->t_ref) > 0);3128 atomic_inc(&ticket->t_ref);3129 return ticket;3130}3131 3132/*3133 * Figure out the total log space unit (in bytes) that would be3134 * required for a log ticket.3135 */3136static int3137xlog_calc_unit_res(3138 struct xlog *log,3139 int unit_bytes,3140 int *niclogs)3141{3142 int iclog_space;3143 uint num_headers;3144 3145 /*3146 * Permanent reservations have up to 'cnt'-1 active log operations3147 * in the log. A unit in this case is the amount of space for one3148 * of these log operations. Normal reservations have a cnt of 13149 * and their unit amount is the total amount of space required.3150 *3151 * The following lines of code account for non-transaction data3152 * which occupy space in the on-disk log.3153 *3154 * Normal form of a transaction is:3155 * <oph><trans-hdr><start-oph><reg1-oph><reg1><reg2-oph>...<commit-oph>3156 * and then there are LR hdrs, split-recs and roundoff at end of syncs.3157 *3158 * We need to account for all the leadup data and trailer data3159 * around the transaction data.3160 * And then we need to account for the worst case in terms of using3161 * more space.3162 * The worst case will happen if:3163 * - the placement of the transaction happens to be such that the3164 * roundoff is at its maximum3165 * - the transaction data is synced before the commit record is synced3166 * i.e. <transaction-data><roundoff> | <commit-rec><roundoff>3167 * Therefore the commit record is in its own Log Record.3168 * This can happen as the commit record is called with its3169 * own region to xlog_write().3170 * This then means that in the worst case, roundoff can happen for3171 * the commit-rec as well.3172 * The commit-rec is smaller than padding in this scenario and so it is3173 * not added separately.3174 */3175 3176 /* for trans header */3177 unit_bytes += sizeof(xlog_op_header_t);3178 unit_bytes += sizeof(xfs_trans_header_t);3179 3180 /* for start-rec */3181 unit_bytes += sizeof(xlog_op_header_t);3182 3183 /*3184 * for LR headers - the space for data in an iclog is the size minus3185 * the space used for the headers. If we use the iclog size, then we3186 * undercalculate the number of headers required.3187 *3188 * Furthermore - the addition of op headers for split-recs might3189 * increase the space required enough to require more log and op3190 * headers, so take that into account too.3191 *3192 * IMPORTANT: This reservation makes the assumption that if this3193 * transaction is the first in an iclog and hence has the LR headers3194 * accounted to it, then the remaining space in the iclog is3195 * exclusively for this transaction. i.e. if the transaction is larger3196 * than the iclog, it will be the only thing in that iclog.3197 * Fundamentally, this means we must pass the entire log vector to3198 * xlog_write to guarantee this.3199 */3200 iclog_space = log->l_iclog_size - log->l_iclog_hsize;3201 num_headers = howmany(unit_bytes, iclog_space);3202 3203 /* for split-recs - ophdrs added when data split over LRs */3204 unit_bytes += sizeof(xlog_op_header_t) * num_headers;3205 3206 /* add extra header reservations if we overrun */3207 while (!num_headers ||3208 howmany(unit_bytes, iclog_space) > num_headers) {3209 unit_bytes += sizeof(xlog_op_header_t);3210 num_headers++;3211 }3212 unit_bytes += log->l_iclog_hsize * num_headers;3213 3214 /* for commit-rec LR header - note: padding will subsume the ophdr */3215 unit_bytes += log->l_iclog_hsize;3216 3217 /* roundoff padding for transaction data and one for commit record */3218 unit_bytes += 2 * log->l_iclog_roundoff;3219 3220 if (niclogs)3221 *niclogs = num_headers;3222 return unit_bytes;3223}3224 3225int3226xfs_log_calc_unit_res(3227 struct xfs_mount *mp,3228 int unit_bytes)3229{3230 return xlog_calc_unit_res(mp->m_log, unit_bytes, NULL);3231}3232 3233/*3234 * Allocate and initialise a new log ticket.3235 */3236struct xlog_ticket *3237xlog_ticket_alloc(3238 struct xlog *log,3239 int unit_bytes,3240 int cnt,3241 bool permanent)3242{3243 struct xlog_ticket *tic;3244 int unit_res;3245 3246 tic = kmem_cache_zalloc(xfs_log_ticket_cache,3247 GFP_KERNEL | __GFP_NOFAIL);3248 3249 unit_res = xlog_calc_unit_res(log, unit_bytes, &tic->t_iclog_hdrs);3250 3251 atomic_set(&tic->t_ref, 1);3252 tic->t_task = current;3253 INIT_LIST_HEAD(&tic->t_queue);3254 tic->t_unit_res = unit_res;3255 tic->t_curr_res = unit_res;3256 tic->t_cnt = cnt;3257 tic->t_ocnt = cnt;3258 tic->t_tid = get_random_u32();3259 if (permanent)3260 tic->t_flags |= XLOG_TIC_PERM_RESERV;3261 3262 return tic;3263}3264 3265#if defined(DEBUG)3266static void3267xlog_verify_dump_tail(3268 struct xlog *log,3269 struct xlog_in_core *iclog)3270{3271 xfs_alert(log->l_mp,3272"ran out of log space tail 0x%llx/0x%llx, head lsn 0x%llx, head 0x%x/0x%x, prev head 0x%x/0x%x",3273 iclog ? be64_to_cpu(iclog->ic_header.h_tail_lsn) : -1,3274 atomic64_read(&log->l_tail_lsn),3275 log->l_ailp->ail_head_lsn,3276 log->l_curr_cycle, log->l_curr_block,3277 log->l_prev_cycle, log->l_prev_block);3278 xfs_alert(log->l_mp,3279"write grant 0x%llx, reserve grant 0x%llx, tail_space 0x%llx, size 0x%x, iclog flags 0x%x",3280 atomic64_read(&log->l_write_head.grant),3281 atomic64_read(&log->l_reserve_head.grant),3282 log->l_tail_space, log->l_logsize,3283 iclog ? iclog->ic_flags : -1);3284}3285 3286/* Check if the new iclog will fit in the log. */3287STATIC void3288xlog_verify_tail_lsn(3289 struct xlog *log,3290 struct xlog_in_core *iclog)3291{3292 xfs_lsn_t tail_lsn = be64_to_cpu(iclog->ic_header.h_tail_lsn);3293 int blocks;3294 3295 if (CYCLE_LSN(tail_lsn) == log->l_prev_cycle) {3296 blocks = log->l_logBBsize -3297 (log->l_prev_block - BLOCK_LSN(tail_lsn));3298 if (blocks < BTOBB(iclog->ic_offset) +3299 BTOBB(log->l_iclog_hsize)) {3300 xfs_emerg(log->l_mp,3301 "%s: ran out of log space", __func__);3302 xlog_verify_dump_tail(log, iclog);3303 }3304 return;3305 }3306 3307 if (CYCLE_LSN(tail_lsn) + 1 != log->l_prev_cycle) {3308 xfs_emerg(log->l_mp, "%s: head has wrapped tail.", __func__);3309 xlog_verify_dump_tail(log, iclog);3310 return;3311 }3312 if (BLOCK_LSN(tail_lsn) == log->l_prev_block) {3313 xfs_emerg(log->l_mp, "%s: tail wrapped", __func__);3314 xlog_verify_dump_tail(log, iclog);3315 return;3316 }3317 3318 blocks = BLOCK_LSN(tail_lsn) - log->l_prev_block;3319 if (blocks < BTOBB(iclog->ic_offset) + 1) {3320 xfs_emerg(log->l_mp, "%s: ran out of iclog space", __func__);3321 xlog_verify_dump_tail(log, iclog);3322 }3323}3324 3325/*3326 * Perform a number of checks on the iclog before writing to disk.3327 *3328 * 1. Make sure the iclogs are still circular3329 * 2. Make sure we have a good magic number3330 * 3. Make sure we don't have magic numbers in the data3331 * 4. Check fields of each log operation header for:3332 * A. Valid client identifier3333 * B. tid ptr value falls in valid ptr space (user space code)3334 * C. Length in log record header is correct according to the3335 * individual operation headers within record.3336 * 5. When a bwrite will occur within 5 blocks of the front of the physical3337 * log, check the preceding blocks of the physical log to make sure all3338 * the cycle numbers agree with the current cycle number.3339 */3340STATIC void3341xlog_verify_iclog(3342 struct xlog *log,3343 struct xlog_in_core *iclog,3344 int count)3345{3346 xlog_op_header_t *ophead;3347 xlog_in_core_t *icptr;3348 xlog_in_core_2_t *xhdr;3349 void *base_ptr, *ptr, *p;3350 ptrdiff_t field_offset;3351 uint8_t clientid;3352 int len, i, j, k, op_len;3353 int idx;3354 3355 /* check validity of iclog pointers */3356 spin_lock(&log->l_icloglock);3357 icptr = log->l_iclog;3358 for (i = 0; i < log->l_iclog_bufs; i++, icptr = icptr->ic_next)3359 ASSERT(icptr);3360 3361 if (icptr != log->l_iclog)3362 xfs_emerg(log->l_mp, "%s: corrupt iclog ring", __func__);3363 spin_unlock(&log->l_icloglock);3364 3365 /* check log magic numbers */3366 if (iclog->ic_header.h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))3367 xfs_emerg(log->l_mp, "%s: invalid magic num", __func__);3368 3369 base_ptr = ptr = &iclog->ic_header;3370 p = &iclog->ic_header;3371 for (ptr += BBSIZE; ptr < base_ptr + count; ptr += BBSIZE) {3372 if (*(__be32 *)ptr == cpu_to_be32(XLOG_HEADER_MAGIC_NUM))3373 xfs_emerg(log->l_mp, "%s: unexpected magic num",3374 __func__);3375 }3376 3377 /* check fields */3378 len = be32_to_cpu(iclog->ic_header.h_num_logops);3379 base_ptr = ptr = iclog->ic_datap;3380 ophead = ptr;3381 xhdr = iclog->ic_data;3382 for (i = 0; i < len; i++) {3383 ophead = ptr;3384 3385 /* clientid is only 1 byte */3386 p = &ophead->oh_clientid;3387 field_offset = p - base_ptr;3388 if (field_offset & 0x1ff) {3389 clientid = ophead->oh_clientid;3390 } else {3391 idx = BTOBBT((void *)&ophead->oh_clientid - iclog->ic_datap);3392 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) {3393 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);3394 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);3395 clientid = xlog_get_client_id(3396 xhdr[j].hic_xheader.xh_cycle_data[k]);3397 } else {3398 clientid = xlog_get_client_id(3399 iclog->ic_header.h_cycle_data[idx]);3400 }3401 }3402 if (clientid != XFS_TRANSACTION && clientid != XFS_LOG) {3403 xfs_warn(log->l_mp,3404 "%s: op %d invalid clientid %d op "PTR_FMT" offset 0x%lx",3405 __func__, i, clientid, ophead,3406 (unsigned long)field_offset);3407 }3408 3409 /* check length */3410 p = &ophead->oh_len;3411 field_offset = p - base_ptr;3412 if (field_offset & 0x1ff) {3413 op_len = be32_to_cpu(ophead->oh_len);3414 } else {3415 idx = BTOBBT((void *)&ophead->oh_len - iclog->ic_datap);3416 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) {3417 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);3418 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);3419 op_len = be32_to_cpu(xhdr[j].hic_xheader.xh_cycle_data[k]);3420 } else {3421 op_len = be32_to_cpu(iclog->ic_header.h_cycle_data[idx]);3422 }3423 }3424 ptr += sizeof(xlog_op_header_t) + op_len;3425 }3426}3427#endif3428 3429/*3430 * Perform a forced shutdown on the log.3431 *3432 * This can be called from low level log code to trigger a shutdown, or from the3433 * high level mount shutdown code when the mount shuts down.3434 *3435 * Our main objectives here are to make sure that:3436 * a. if the shutdown was not due to a log IO error, flush the logs to3437 * disk. Anything modified after this is ignored.3438 * b. the log gets atomically marked 'XLOG_IO_ERROR' for all interested3439 * parties to find out. Nothing new gets queued after this is done.3440 * c. Tasks sleeping on log reservations, pinned objects and3441 * other resources get woken up.3442 * d. The mount is also marked as shut down so that log triggered shutdowns3443 * still behave the same as if they called xfs_forced_shutdown().3444 *3445 * Return true if the shutdown cause was a log IO error and we actually shut the3446 * log down.3447 */3448bool3449xlog_force_shutdown(3450 struct xlog *log,3451 uint32_t shutdown_flags)3452{3453 bool log_error = (shutdown_flags & SHUTDOWN_LOG_IO_ERROR);3454 3455 if (!log)3456 return false;3457 3458 /*3459 * Flush all the completed transactions to disk before marking the log3460 * being shut down. We need to do this first as shutting down the log3461 * before the force will prevent the log force from flushing the iclogs3462 * to disk.3463 *3464 * When we are in recovery, there are no transactions to flush, and3465 * we don't want to touch the log because we don't want to perturb the3466 * current head/tail for future recovery attempts. Hence we need to3467 * avoid a log force in this case.3468 *3469 * If we are shutting down due to a log IO error, then we must avoid3470 * trying to write the log as that may just result in more IO errors and3471 * an endless shutdown/force loop.3472 */3473 if (!log_error && !xlog_in_recovery(log))3474 xfs_log_force(log->l_mp, XFS_LOG_SYNC);3475 3476 /*3477 * Atomically set the shutdown state. If the shutdown state is already3478 * set, there someone else is performing the shutdown and so we are done3479 * here. This should never happen because we should only ever get called3480 * once by the first shutdown caller.3481 *3482 * Much of the log state machine transitions assume that shutdown state3483 * cannot change once they hold the log->l_icloglock. Hence we need to3484 * hold that lock here, even though we use the atomic test_and_set_bit()3485 * operation to set the shutdown state.3486 */3487 spin_lock(&log->l_icloglock);3488 if (test_and_set_bit(XLOG_IO_ERROR, &log->l_opstate)) {3489 spin_unlock(&log->l_icloglock);3490 return false;3491 }3492 spin_unlock(&log->l_icloglock);3493 3494 /*3495 * If this log shutdown also sets the mount shutdown state, issue a3496 * shutdown warning message.3497 */3498 if (!xfs_set_shutdown(log->l_mp)) {3499 xfs_alert_tag(log->l_mp, XFS_PTAG_SHUTDOWN_LOGERROR,3500"Filesystem has been shut down due to log error (0x%x).",3501 shutdown_flags);3502 xfs_alert(log->l_mp,3503"Please unmount the filesystem and rectify the problem(s).");3504 if (xfs_error_level >= XFS_ERRLEVEL_HIGH)3505 xfs_stack_trace();3506 }3507 3508 /*3509 * We don't want anybody waiting for log reservations after this. That3510 * means we have to wake up everybody queued up on reserveq as well as3511 * writeq. In addition, we make sure in xlog_{re}grant_log_space that3512 * we don't enqueue anything once the SHUTDOWN flag is set, and this3513 * action is protected by the grant locks.3514 */3515 xlog_grant_head_wake_all(&log->l_reserve_head);3516 xlog_grant_head_wake_all(&log->l_write_head);3517 3518 /*3519 * Wake up everybody waiting on xfs_log_force. Wake the CIL push first3520 * as if the log writes were completed. The abort handling in the log3521 * item committed callback functions will do this again under lock to3522 * avoid races.3523 */3524 spin_lock(&log->l_cilp->xc_push_lock);3525 wake_up_all(&log->l_cilp->xc_start_wait);3526 wake_up_all(&log->l_cilp->xc_commit_wait);3527 spin_unlock(&log->l_cilp->xc_push_lock);3528 3529 spin_lock(&log->l_icloglock);3530 xlog_state_shutdown_callbacks(log);3531 spin_unlock(&log->l_icloglock);3532 3533 wake_up_var(&log->l_opstate);3534 return log_error;3535}3536 3537STATIC int3538xlog_iclogs_empty(3539 struct xlog *log)3540{3541 xlog_in_core_t *iclog;3542 3543 iclog = log->l_iclog;3544 do {3545 /* endianness does not matter here, zero is zero in3546 * any language.3547 */3548 if (iclog->ic_header.h_num_logops)3549 return 0;3550 iclog = iclog->ic_next;3551 } while (iclog != log->l_iclog);3552 return 1;3553}3554 3555/*3556 * Verify that an LSN stamped into a piece of metadata is valid. This is3557 * intended for use in read verifiers on v5 superblocks.3558 */3559bool3560xfs_log_check_lsn(3561 struct xfs_mount *mp,3562 xfs_lsn_t lsn)3563{3564 struct xlog *log = mp->m_log;3565 bool valid;3566 3567 /*3568 * norecovery mode skips mount-time log processing and unconditionally3569 * resets the in-core LSN. We can't validate in this mode, but3570 * modifications are not allowed anyways so just return true.3571 */3572 if (xfs_has_norecovery(mp))3573 return true;3574 3575 /*3576 * Some metadata LSNs are initialized to NULL (e.g., the agfl). This is3577 * handled by recovery and thus safe to ignore here.3578 */3579 if (lsn == NULLCOMMITLSN)3580 return true;3581 3582 valid = xlog_valid_lsn(mp->m_log, lsn);3583 3584 /* warn the user about what's gone wrong before verifier failure */3585 if (!valid) {3586 spin_lock(&log->l_icloglock);3587 xfs_warn(mp,3588"Corruption warning: Metadata has LSN (%d:%d) ahead of current LSN (%d:%d). "3589"Please unmount and run xfs_repair (>= v4.3) to resolve.",3590 CYCLE_LSN(lsn), BLOCK_LSN(lsn),3591 log->l_curr_cycle, log->l_curr_block);3592 spin_unlock(&log->l_icloglock);3593 }3594 3595 return valid;3596}3597