1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
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"
18 #include "xfs_log_priv.h"
19 #include "xfs_trace.h"
20 #include "xfs_sysfs.h"
22 #include "xfs_health.h"
24 kmem_zone_t *xfs_log_ticket_zone;
26 /* Local miscellaneous function prototypes */
30 struct xfs_buftarg *log_target,
31 xfs_daddr_t blk_offset,
41 /* local state machine functions */
42 STATIC void xlog_state_done_syncing(
43 struct xlog_in_core *iclog);
45 xlog_state_get_iclog_space(
48 struct xlog_in_core **iclog,
49 struct xlog_ticket *ticket,
53 xlog_state_switch_iclogs(
55 struct xlog_in_core *iclog,
64 struct xlog_in_core *iclog);
71 xlog_verify_grant_tail(
76 struct xlog_in_core *iclog,
81 struct xlog_in_core *iclog,
84 #define xlog_verify_dest_ptr(a,b)
85 #define xlog_verify_grant_tail(a)
86 #define xlog_verify_iclog(a,b,c)
87 #define xlog_verify_tail_lsn(a,b,c)
95 xfs_log_cover(struct xfs_mount *);
103 int64_t head_val = atomic64_read(head);
109 xlog_crack_grant_head_val(head_val, &cycle, &space);
113 space += log->l_logsize;
118 new = xlog_assign_grant_head_val(cycle, space);
119 head_val = atomic64_cmpxchg(head, old, new);
120 } while (head_val != old);
124 xlog_grant_add_space(
129 int64_t head_val = atomic64_read(head);
136 xlog_crack_grant_head_val(head_val, &cycle, &space);
138 tmp = log->l_logsize - space;
147 new = xlog_assign_grant_head_val(cycle, space);
148 head_val = atomic64_cmpxchg(head, old, new);
149 } while (head_val != old);
153 xlog_grant_head_init(
154 struct xlog_grant_head *head)
156 xlog_assign_grant_head(&head->grant, 1, 0);
157 INIT_LIST_HEAD(&head->waiters);
158 spin_lock_init(&head->lock);
162 xlog_grant_head_wake_all(
163 struct xlog_grant_head *head)
165 struct xlog_ticket *tic;
167 spin_lock(&head->lock);
168 list_for_each_entry(tic, &head->waiters, t_queue)
169 wake_up_process(tic->t_task);
170 spin_unlock(&head->lock);
174 xlog_ticket_reservation(
176 struct xlog_grant_head *head,
177 struct xlog_ticket *tic)
179 if (head == &log->l_write_head) {
180 ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV);
181 return tic->t_unit_res;
183 if (tic->t_flags & XLOG_TIC_PERM_RESERV)
184 return tic->t_unit_res * tic->t_cnt;
186 return tic->t_unit_res;
191 xlog_grant_head_wake(
193 struct xlog_grant_head *head,
196 struct xlog_ticket *tic;
198 bool woken_task = false;
200 list_for_each_entry(tic, &head->waiters, t_queue) {
203 * There is a chance that the size of the CIL checkpoints in
204 * progress at the last AIL push target calculation resulted in
205 * limiting the target to the log head (l_last_sync_lsn) at the
206 * time. This may not reflect where the log head is now as the
207 * CIL checkpoints may have completed.
209 * Hence when we are woken here, it may be that the head of the
210 * log that has moved rather than the tail. As the tail didn't
211 * move, there still won't be space available for the
212 * reservation we require. However, if the AIL has already
213 * pushed to the target defined by the old log head location, we
214 * will hang here waiting for something else to update the AIL
217 * Therefore, if there isn't space to wake the first waiter on
218 * the grant head, we need to push the AIL again to ensure the
219 * target reflects both the current log tail and log head
220 * position before we wait for the tail to move again.
223 need_bytes = xlog_ticket_reservation(log, head, tic);
224 if (*free_bytes < need_bytes) {
226 xlog_grant_push_ail(log, need_bytes);
230 *free_bytes -= need_bytes;
231 trace_xfs_log_grant_wake_up(log, tic);
232 wake_up_process(tic->t_task);
240 xlog_grant_head_wait(
242 struct xlog_grant_head *head,
243 struct xlog_ticket *tic,
244 int need_bytes) __releases(&head->lock)
245 __acquires(&head->lock)
247 list_add_tail(&tic->t_queue, &head->waiters);
250 if (XLOG_FORCED_SHUTDOWN(log))
252 xlog_grant_push_ail(log, need_bytes);
254 __set_current_state(TASK_UNINTERRUPTIBLE);
255 spin_unlock(&head->lock);
257 XFS_STATS_INC(log->l_mp, xs_sleep_logspace);
259 trace_xfs_log_grant_sleep(log, tic);
261 trace_xfs_log_grant_wake(log, tic);
263 spin_lock(&head->lock);
264 if (XLOG_FORCED_SHUTDOWN(log))
266 } while (xlog_space_left(log, &head->grant) < need_bytes);
268 list_del_init(&tic->t_queue);
271 list_del_init(&tic->t_queue);
276 * Atomically get the log space required for a log ticket.
278 * Once a ticket gets put onto head->waiters, it will only return after the
279 * needed reservation is satisfied.
281 * This function is structured so that it has a lock free fast path. This is
282 * necessary because every new transaction reservation will come through this
283 * path. Hence any lock will be globally hot if we take it unconditionally on
286 * As tickets are only ever moved on and off head->waiters under head->lock, we
287 * only need to take that lock if we are going to add the ticket to the queue
288 * and sleep. We can avoid taking the lock if the ticket was never added to
289 * head->waiters because the t_queue list head will be empty and we hold the
290 * only reference to it so it can safely be checked unlocked.
293 xlog_grant_head_check(
295 struct xlog_grant_head *head,
296 struct xlog_ticket *tic,
302 ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY));
305 * If there are other waiters on the queue then give them a chance at
306 * logspace before us. Wake up the first waiters, if we do not wake
307 * up all the waiters then go to sleep waiting for more free space,
308 * otherwise try to get some space for this transaction.
310 *need_bytes = xlog_ticket_reservation(log, head, tic);
311 free_bytes = xlog_space_left(log, &head->grant);
312 if (!list_empty_careful(&head->waiters)) {
313 spin_lock(&head->lock);
314 if (!xlog_grant_head_wake(log, head, &free_bytes) ||
315 free_bytes < *need_bytes) {
316 error = xlog_grant_head_wait(log, head, tic,
319 spin_unlock(&head->lock);
320 } else if (free_bytes < *need_bytes) {
321 spin_lock(&head->lock);
322 error = xlog_grant_head_wait(log, head, tic, *need_bytes);
323 spin_unlock(&head->lock);
330 xlog_tic_reset_res(xlog_ticket_t *tic)
333 tic->t_res_arr_sum = 0;
334 tic->t_res_num_ophdrs = 0;
338 xlog_tic_add_region(xlog_ticket_t *tic, uint len, uint type)
340 if (tic->t_res_num == XLOG_TIC_LEN_MAX) {
341 /* add to overflow and start again */
342 tic->t_res_o_flow += tic->t_res_arr_sum;
344 tic->t_res_arr_sum = 0;
347 tic->t_res_arr[tic->t_res_num].r_len = len;
348 tic->t_res_arr[tic->t_res_num].r_type = type;
349 tic->t_res_arr_sum += len;
355 struct xfs_mount *mp)
358 * Never write to the log on norecovery mounts, if the block device is
359 * read-only, or if the filesystem is shutdown. Read-only mounts still
360 * allow internal writes for log recovery and unmount purposes, so don't
361 * restrict that case here.
363 if (mp->m_flags & XFS_MOUNT_NORECOVERY)
365 if (xfs_readonly_buftarg(mp->m_log->l_targ))
367 if (XFS_FORCED_SHUTDOWN(mp))
373 * Replenish the byte reservation required by moving the grant write head.
377 struct xfs_mount *mp,
378 struct xlog_ticket *tic)
380 struct xlog *log = mp->m_log;
384 if (XLOG_FORCED_SHUTDOWN(log))
387 XFS_STATS_INC(mp, xs_try_logspace);
390 * This is a new transaction on the ticket, so we need to change the
391 * transaction ID so that the next transaction has a different TID in
392 * the log. Just add one to the existing tid so that we can see chains
393 * of rolling transactions in the log easily.
397 xlog_grant_push_ail(log, tic->t_unit_res);
399 tic->t_curr_res = tic->t_unit_res;
400 xlog_tic_reset_res(tic);
405 trace_xfs_log_regrant(log, tic);
407 error = xlog_grant_head_check(log, &log->l_write_head, tic,
412 xlog_grant_add_space(log, &log->l_write_head.grant, need_bytes);
413 trace_xfs_log_regrant_exit(log, tic);
414 xlog_verify_grant_tail(log);
419 * If we are failing, make sure the ticket doesn't have any current
420 * reservations. We don't want to add this back when the ticket/
421 * transaction gets cancelled.
424 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */
429 * Reserve log space and return a ticket corresponding to the reservation.
431 * Each reservation is going to reserve extra space for a log record header.
432 * When writes happen to the on-disk log, we don't subtract the length of the
433 * log record header from any reservation. By wasting space in each
434 * reservation, we prevent over allocation problems.
438 struct xfs_mount *mp,
441 struct xlog_ticket **ticp,
445 struct xlog *log = mp->m_log;
446 struct xlog_ticket *tic;
450 ASSERT(client == XFS_TRANSACTION || client == XFS_LOG);
452 if (XLOG_FORCED_SHUTDOWN(log))
455 XFS_STATS_INC(mp, xs_try_logspace);
457 ASSERT(*ticp == NULL);
458 tic = xlog_ticket_alloc(log, unit_bytes, cnt, client, permanent);
461 xlog_grant_push_ail(log, tic->t_cnt ? tic->t_unit_res * tic->t_cnt
464 trace_xfs_log_reserve(log, tic);
466 error = xlog_grant_head_check(log, &log->l_reserve_head, tic,
471 xlog_grant_add_space(log, &log->l_reserve_head.grant, need_bytes);
472 xlog_grant_add_space(log, &log->l_write_head.grant, need_bytes);
473 trace_xfs_log_reserve_exit(log, tic);
474 xlog_verify_grant_tail(log);
479 * If we are failing, make sure the ticket doesn't have any current
480 * reservations. We don't want to add this back when the ticket/
481 * transaction gets cancelled.
484 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */
489 __xlog_state_release_iclog(
491 struct xlog_in_core *iclog)
493 lockdep_assert_held(&log->l_icloglock);
495 if (iclog->ic_state == XLOG_STATE_WANT_SYNC) {
496 /* update tail before writing to iclog */
497 xfs_lsn_t tail_lsn = xlog_assign_tail_lsn(log->l_mp);
499 iclog->ic_state = XLOG_STATE_SYNCING;
500 iclog->ic_header.h_tail_lsn = cpu_to_be64(tail_lsn);
501 xlog_verify_tail_lsn(log, iclog, tail_lsn);
502 /* cycle incremented when incrementing curr_block */
506 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);
511 * Flush iclog to disk if this is the last reference to the given iclog and the
512 * it is in the WANT_SYNC state.
515 xlog_state_release_iclog(
517 struct xlog_in_core *iclog)
519 lockdep_assert_held(&log->l_icloglock);
521 if (iclog->ic_state == XLOG_STATE_IOERROR)
524 if (atomic_dec_and_test(&iclog->ic_refcnt) &&
525 __xlog_state_release_iclog(log, iclog)) {
526 spin_unlock(&log->l_icloglock);
527 xlog_sync(log, iclog);
528 spin_lock(&log->l_icloglock);
535 xfs_log_release_iclog(
536 struct xlog_in_core *iclog)
538 struct xlog *log = iclog->ic_log;
541 if (atomic_dec_and_lock(&iclog->ic_refcnt, &log->l_icloglock)) {
542 if (iclog->ic_state != XLOG_STATE_IOERROR)
543 sync = __xlog_state_release_iclog(log, iclog);
544 spin_unlock(&log->l_icloglock);
548 xlog_sync(log, iclog);
552 * Mount a log filesystem
554 * mp - ubiquitous xfs mount point structure
555 * log_target - buftarg of on-disk log device
556 * blk_offset - Start block # where block size is 512 bytes (BBSIZE)
557 * num_bblocks - Number of BBSIZE blocks in on-disk log
559 * Return error or zero.
564 xfs_buftarg_t *log_target,
565 xfs_daddr_t blk_offset,
568 bool fatal = xfs_sb_version_hascrc(&mp->m_sb);
572 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) {
573 xfs_notice(mp, "Mounting V%d Filesystem",
574 XFS_SB_VERSION_NUM(&mp->m_sb));
577 "Mounting V%d filesystem in no-recovery mode. Filesystem will be inconsistent.",
578 XFS_SB_VERSION_NUM(&mp->m_sb));
579 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
582 mp->m_log = xlog_alloc_log(mp, log_target, blk_offset, num_bblks);
583 if (IS_ERR(mp->m_log)) {
584 error = PTR_ERR(mp->m_log);
589 * Validate the given log space and drop a critical message via syslog
590 * if the log size is too small that would lead to some unexpected
591 * situations in transaction log space reservation stage.
593 * Note: we can't just reject the mount if the validation fails. This
594 * would mean that people would have to downgrade their kernel just to
595 * remedy the situation as there is no way to grow the log (short of
596 * black magic surgery with xfs_db).
598 * We can, however, reject mounts for CRC format filesystems, as the
599 * mkfs binary being used to make the filesystem should never create a
600 * filesystem with a log that is too small.
602 min_logfsbs = xfs_log_calc_minimum_size(mp);
604 if (mp->m_sb.sb_logblocks < min_logfsbs) {
606 "Log size %d blocks too small, minimum size is %d blocks",
607 mp->m_sb.sb_logblocks, min_logfsbs);
609 } else if (mp->m_sb.sb_logblocks > XFS_MAX_LOG_BLOCKS) {
611 "Log size %d blocks too large, maximum size is %lld blocks",
612 mp->m_sb.sb_logblocks, XFS_MAX_LOG_BLOCKS);
614 } else if (XFS_FSB_TO_B(mp, mp->m_sb.sb_logblocks) > XFS_MAX_LOG_BYTES) {
616 "log size %lld bytes too large, maximum size is %lld bytes",
617 XFS_FSB_TO_B(mp, mp->m_sb.sb_logblocks),
620 } else if (mp->m_sb.sb_logsunit > 1 &&
621 mp->m_sb.sb_logsunit % mp->m_sb.sb_blocksize) {
623 "log stripe unit %u bytes must be a multiple of block size",
624 mp->m_sb.sb_logsunit);
630 * Log check errors are always fatal on v5; or whenever bad
631 * metadata leads to a crash.
634 xfs_crit(mp, "AAIEEE! Log failed size checks. Abort!");
638 xfs_crit(mp, "Log size out of supported range.");
640 "Continuing onwards, but if log hangs are experienced then please report this message in the bug report.");
644 * Initialize the AIL now we have a log.
646 error = xfs_trans_ail_init(mp);
648 xfs_warn(mp, "AIL initialisation failed: error %d", error);
651 mp->m_log->l_ailp = mp->m_ail;
654 * skip log recovery on a norecovery mount. pretend it all
657 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) {
658 int readonly = (mp->m_flags & XFS_MOUNT_RDONLY);
661 mp->m_flags &= ~XFS_MOUNT_RDONLY;
663 error = xlog_recover(mp->m_log);
666 mp->m_flags |= XFS_MOUNT_RDONLY;
668 xfs_warn(mp, "log mount/recovery failed: error %d",
670 xlog_recover_cancel(mp->m_log);
671 goto out_destroy_ail;
675 error = xfs_sysfs_init(&mp->m_log->l_kobj, &xfs_log_ktype, &mp->m_kobj,
678 goto out_destroy_ail;
680 /* Normal transactions can now occur */
681 mp->m_log->l_flags &= ~XLOG_ACTIVE_RECOVERY;
684 * Now the log has been fully initialised and we know were our
685 * space grant counters are, we can initialise the permanent ticket
686 * needed for delayed logging to work.
688 xlog_cil_init_post_recovery(mp->m_log);
693 xfs_trans_ail_destroy(mp);
695 xlog_dealloc_log(mp->m_log);
701 * Finish the recovery of the file system. This is separate from the
702 * xfs_log_mount() call, because it depends on the code in xfs_mountfs() to read
703 * in the root and real-time bitmap inodes between calling xfs_log_mount() and
706 * If we finish recovery successfully, start the background log work. If we are
707 * not doing recovery, then we have a RO filesystem and we don't need to start
711 xfs_log_mount_finish(
712 struct xfs_mount *mp)
715 bool readonly = (mp->m_flags & XFS_MOUNT_RDONLY);
716 bool recovered = mp->m_log->l_flags & XLOG_RECOVERY_NEEDED;
718 if (mp->m_flags & XFS_MOUNT_NORECOVERY) {
719 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
721 } else if (readonly) {
722 /* Allow unlinked processing to proceed */
723 mp->m_flags &= ~XFS_MOUNT_RDONLY;
727 * During the second phase of log recovery, we need iget and
728 * iput to behave like they do for an active filesystem.
729 * xfs_fs_drop_inode needs to be able to prevent the deletion
730 * of inodes before we're done replaying log items on those
731 * inodes. Turn it off immediately after recovery finishes
732 * so that we don't leak the quota inodes if subsequent mount
735 * We let all inodes involved in redo item processing end up on
736 * the LRU instead of being evicted immediately so that if we do
737 * something to an unlinked inode, the irele won't cause
738 * premature truncation and freeing of the inode, which results
739 * in log recovery failure. We have to evict the unreferenced
740 * lru inodes after clearing SB_ACTIVE because we don't
741 * otherwise clean up the lru if there's a subsequent failure in
742 * xfs_mountfs, which leads to us leaking the inodes if nothing
743 * else (e.g. quotacheck) references the inodes before the
744 * mount failure occurs.
746 mp->m_super->s_flags |= SB_ACTIVE;
747 error = xlog_recover_finish(mp->m_log);
749 xfs_log_work_queue(mp);
750 mp->m_super->s_flags &= ~SB_ACTIVE;
751 evict_inodes(mp->m_super);
754 * Drain the buffer LRU after log recovery. This is required for v4
755 * filesystems to avoid leaving around buffers with NULL verifier ops,
756 * but we do it unconditionally to make sure we're always in a clean
757 * cache state after mount.
759 * Don't push in the error case because the AIL may have pending intents
760 * that aren't removed until recovery is cancelled.
762 if (!error && recovered) {
763 xfs_log_force(mp, XFS_LOG_SYNC);
764 xfs_ail_push_all_sync(mp->m_ail);
766 xfs_buftarg_drain(mp->m_ddev_targp);
769 mp->m_flags |= XFS_MOUNT_RDONLY;
775 * The mount has failed. Cancel the recovery if it hasn't completed and destroy
779 xfs_log_mount_cancel(
780 struct xfs_mount *mp)
782 xlog_recover_cancel(mp->m_log);
787 * Wait for the iclog to be written disk, or return an error if the log has been
792 struct xlog_in_core *iclog)
793 __releases(iclog->ic_log->l_icloglock)
795 struct xlog *log = iclog->ic_log;
797 if (!XLOG_FORCED_SHUTDOWN(log) &&
798 iclog->ic_state != XLOG_STATE_ACTIVE &&
799 iclog->ic_state != XLOG_STATE_DIRTY) {
800 XFS_STATS_INC(log->l_mp, xs_log_force_sleep);
801 xlog_wait(&iclog->ic_force_wait, &log->l_icloglock);
803 spin_unlock(&log->l_icloglock);
806 if (XLOG_FORCED_SHUTDOWN(log))
812 * Write out an unmount record using the ticket provided. We have to account for
813 * the data space used in the unmount ticket as this write is not done from a
814 * transaction context that has already done the accounting for us.
817 xlog_write_unmount_record(
819 struct xlog_ticket *ticket,
823 struct xfs_unmount_log_format ulf = {
824 .magic = XLOG_UNMOUNT_TYPE,
826 struct xfs_log_iovec reg = {
828 .i_len = sizeof(ulf),
829 .i_type = XLOG_REG_TYPE_UNMOUNT,
831 struct xfs_log_vec vec = {
836 /* account for space used by record data */
837 ticket->t_curr_res -= sizeof(ulf);
838 return xlog_write(log, &vec, ticket, lsn, NULL, flags, false);
842 * Mark the filesystem clean by writing an unmount record to the head of the
849 struct xfs_mount *mp = log->l_mp;
850 struct xlog_in_core *iclog;
851 struct xlog_ticket *tic = NULL;
853 uint flags = XLOG_UNMOUNT_TRANS;
856 error = xfs_log_reserve(mp, 600, 1, &tic, XFS_LOG, 0);
860 error = xlog_write_unmount_record(log, tic, &lsn, flags);
862 * At this point, we're umounting anyway, so there's no point in
863 * transitioning log state to IOERROR. Just continue...
867 xfs_alert(mp, "%s: unmount record failed", __func__);
869 spin_lock(&log->l_icloglock);
870 iclog = log->l_iclog;
871 atomic_inc(&iclog->ic_refcnt);
872 if (iclog->ic_state == XLOG_STATE_ACTIVE)
873 xlog_state_switch_iclogs(log, iclog, 0);
875 ASSERT(iclog->ic_state == XLOG_STATE_WANT_SYNC ||
876 iclog->ic_state == XLOG_STATE_IOERROR);
877 error = xlog_state_release_iclog(log, iclog);
878 xlog_wait_on_iclog(iclog);
881 trace_xfs_log_umount_write(log, tic);
882 xfs_log_ticket_ungrant(log, tic);
887 xfs_log_unmount_verify_iclog(
890 struct xlog_in_core *iclog = log->l_iclog;
893 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);
894 ASSERT(iclog->ic_offset == 0);
895 } while ((iclog = iclog->ic_next) != log->l_iclog);
899 * Unmount record used to have a string "Unmount filesystem--" in the
900 * data section where the "Un" was really a magic number (XLOG_UNMOUNT_TYPE).
901 * We just write the magic number now since that particular field isn't
902 * currently architecture converted and "Unmount" is a bit foo.
903 * As far as I know, there weren't any dependencies on the old behaviour.
906 xfs_log_unmount_write(
907 struct xfs_mount *mp)
909 struct xlog *log = mp->m_log;
911 if (!xfs_log_writable(mp))
914 xfs_log_force(mp, XFS_LOG_SYNC);
916 if (XLOG_FORCED_SHUTDOWN(log))
920 * If we think the summary counters are bad, avoid writing the unmount
921 * record to force log recovery at next mount, after which the summary
922 * counters will be recalculated. Refer to xlog_check_unmount_rec for
925 if (XFS_TEST_ERROR(xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS), mp,
926 XFS_ERRTAG_FORCE_SUMMARY_RECALC)) {
927 xfs_alert(mp, "%s: will fix summary counters at next mount",
932 xfs_log_unmount_verify_iclog(log);
933 xlog_unmount_write(log);
937 * Empty the log for unmount/freeze.
939 * To do this, we first need to shut down the background log work so it is not
940 * trying to cover the log as we clean up. We then need to unpin all objects in
941 * the log so we can then flush them out. Once they have completed their IO and
942 * run the callbacks removing themselves from the AIL, we can cover the log.
946 struct xfs_mount *mp)
948 cancel_delayed_work_sync(&mp->m_log->l_work);
949 xfs_log_force(mp, XFS_LOG_SYNC);
952 * The superblock buffer is uncached and while xfs_ail_push_all_sync()
953 * will push it, xfs_buftarg_wait() will not wait for it. Further,
954 * xfs_buf_iowait() cannot be used because it was pushed with the
955 * XBF_ASYNC flag set, so we need to use a lock/unlock pair to wait for
956 * the IO to complete.
958 xfs_ail_push_all_sync(mp->m_ail);
959 xfs_buftarg_wait(mp->m_ddev_targp);
960 xfs_buf_lock(mp->m_sb_bp);
961 xfs_buf_unlock(mp->m_sb_bp);
963 return xfs_log_cover(mp);
968 struct xfs_mount *mp)
971 xfs_log_unmount_write(mp);
975 * Shut down and release the AIL and Log.
977 * During unmount, we need to ensure we flush all the dirty metadata objects
978 * from the AIL so that the log is empty before we write the unmount record to
979 * the log. Once this is done, we can tear down the AIL and the log.
983 struct xfs_mount *mp)
987 xfs_buftarg_drain(mp->m_ddev_targp);
989 xfs_trans_ail_destroy(mp);
991 xfs_sysfs_del(&mp->m_log->l_kobj);
993 xlog_dealloc_log(mp->m_log);
998 struct xfs_mount *mp,
999 struct xfs_log_item *item,
1001 const struct xfs_item_ops *ops)
1003 item->li_mountp = mp;
1004 item->li_ailp = mp->m_ail;
1005 item->li_type = type;
1009 INIT_LIST_HEAD(&item->li_ail);
1010 INIT_LIST_HEAD(&item->li_cil);
1011 INIT_LIST_HEAD(&item->li_bio_list);
1012 INIT_LIST_HEAD(&item->li_trans);
1016 * Wake up processes waiting for log space after we have moved the log tail.
1020 struct xfs_mount *mp)
1022 struct xlog *log = mp->m_log;
1025 if (XLOG_FORCED_SHUTDOWN(log))
1028 if (!list_empty_careful(&log->l_write_head.waiters)) {
1029 ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY));
1031 spin_lock(&log->l_write_head.lock);
1032 free_bytes = xlog_space_left(log, &log->l_write_head.grant);
1033 xlog_grant_head_wake(log, &log->l_write_head, &free_bytes);
1034 spin_unlock(&log->l_write_head.lock);
1037 if (!list_empty_careful(&log->l_reserve_head.waiters)) {
1038 ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY));
1040 spin_lock(&log->l_reserve_head.lock);
1041 free_bytes = xlog_space_left(log, &log->l_reserve_head.grant);
1042 xlog_grant_head_wake(log, &log->l_reserve_head, &free_bytes);
1043 spin_unlock(&log->l_reserve_head.lock);
1048 * Determine if we have a transaction that has gone to disk that needs to be
1049 * covered. To begin the transition to the idle state firstly the log needs to
1050 * be idle. That means the CIL, the AIL and the iclogs needs to be empty before
1051 * we start attempting to cover the log.
1053 * Only if we are then in a state where covering is needed, the caller is
1054 * informed that dummy transactions are required to move the log into the idle
1057 * If there are any items in the AIl or CIL, then we do not want to attempt to
1058 * cover the log as we may be in a situation where there isn't log space
1059 * available to run a dummy transaction and this can lead to deadlocks when the
1060 * tail of the log is pinned by an item that is modified in the CIL. Hence
1061 * there's no point in running a dummy transaction at this point because we
1062 * can't start trying to idle the log until both the CIL and AIL are empty.
1065 xfs_log_need_covered(
1066 struct xfs_mount *mp)
1068 struct xlog *log = mp->m_log;
1069 bool needed = false;
1071 if (!xlog_cil_empty(log))
1074 spin_lock(&log->l_icloglock);
1075 switch (log->l_covered_state) {
1076 case XLOG_STATE_COVER_DONE:
1077 case XLOG_STATE_COVER_DONE2:
1078 case XLOG_STATE_COVER_IDLE:
1080 case XLOG_STATE_COVER_NEED:
1081 case XLOG_STATE_COVER_NEED2:
1082 if (xfs_ail_min_lsn(log->l_ailp))
1084 if (!xlog_iclogs_empty(log))
1088 if (log->l_covered_state == XLOG_STATE_COVER_NEED)
1089 log->l_covered_state = XLOG_STATE_COVER_DONE;
1091 log->l_covered_state = XLOG_STATE_COVER_DONE2;
1097 spin_unlock(&log->l_icloglock);
1102 * Explicitly cover the log. This is similar to background log covering but
1103 * intended for usage in quiesce codepaths. The caller is responsible to ensure
1104 * the log is idle and suitable for covering. The CIL, iclog buffers and AIL
1105 * must all be empty.
1109 struct xfs_mount *mp)
1114 ASSERT((xlog_cil_empty(mp->m_log) && xlog_iclogs_empty(mp->m_log) &&
1115 !xfs_ail_min_lsn(mp->m_log->l_ailp)) ||
1116 XFS_FORCED_SHUTDOWN(mp));
1118 if (!xfs_log_writable(mp))
1122 * xfs_log_need_covered() is not idempotent because it progresses the
1123 * state machine if the log requires covering. Therefore, we must call
1124 * this function once and use the result until we've issued an sb sync.
1125 * Do so first to make that abundantly clear.
1127 * Fall into the covering sequence if the log needs covering or the
1128 * mount has lazy superblock accounting to sync to disk. The sb sync
1129 * used for covering accumulates the in-core counters, so covering
1130 * handles this for us.
1132 need_covered = xfs_log_need_covered(mp);
1133 if (!need_covered && !xfs_sb_version_haslazysbcount(&mp->m_sb))
1137 * To cover the log, commit the superblock twice (at most) in
1138 * independent checkpoints. The first serves as a reference for the
1139 * tail pointer. The sync transaction and AIL push empties the AIL and
1140 * updates the in-core tail to the LSN of the first checkpoint. The
1141 * second commit updates the on-disk tail with the in-core LSN,
1142 * covering the log. Push the AIL one more time to leave it empty, as
1146 error = xfs_sync_sb(mp, true);
1149 xfs_ail_push_all_sync(mp->m_ail);
1150 } while (xfs_log_need_covered(mp));
1156 * We may be holding the log iclog lock upon entering this routine.
1159 xlog_assign_tail_lsn_locked(
1160 struct xfs_mount *mp)
1162 struct xlog *log = mp->m_log;
1163 struct xfs_log_item *lip;
1166 assert_spin_locked(&mp->m_ail->ail_lock);
1169 * To make sure we always have a valid LSN for the log tail we keep
1170 * track of the last LSN which was committed in log->l_last_sync_lsn,
1171 * and use that when the AIL was empty.
1173 lip = xfs_ail_min(mp->m_ail);
1175 tail_lsn = lip->li_lsn;
1177 tail_lsn = atomic64_read(&log->l_last_sync_lsn);
1178 trace_xfs_log_assign_tail_lsn(log, tail_lsn);
1179 atomic64_set(&log->l_tail_lsn, tail_lsn);
1184 xlog_assign_tail_lsn(
1185 struct xfs_mount *mp)
1189 spin_lock(&mp->m_ail->ail_lock);
1190 tail_lsn = xlog_assign_tail_lsn_locked(mp);
1191 spin_unlock(&mp->m_ail->ail_lock);
1197 * Return the space in the log between the tail and the head. The head
1198 * is passed in the cycle/bytes formal parms. In the special case where
1199 * the reserve head has wrapped passed the tail, this calculation is no
1200 * longer valid. In this case, just return 0 which means there is no space
1201 * in the log. This works for all places where this function is called
1202 * with the reserve head. Of course, if the write head were to ever
1203 * wrap the tail, we should blow up. Rather than catch this case here,
1204 * we depend on other ASSERTions in other parts of the code. XXXmiken
1206 * This code also handles the case where the reservation head is behind
1207 * the tail. The details of this case are described below, but the end
1208 * result is that we return the size of the log as the amount of space left.
1221 xlog_crack_grant_head(head, &head_cycle, &head_bytes);
1222 xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_bytes);
1223 tail_bytes = BBTOB(tail_bytes);
1224 if (tail_cycle == head_cycle && head_bytes >= tail_bytes)
1225 free_bytes = log->l_logsize - (head_bytes - tail_bytes);
1226 else if (tail_cycle + 1 < head_cycle)
1228 else if (tail_cycle < head_cycle) {
1229 ASSERT(tail_cycle == (head_cycle - 1));
1230 free_bytes = tail_bytes - head_bytes;
1233 * The reservation head is behind the tail.
1234 * In this case we just want to return the size of the
1235 * log as the amount of space left.
1237 xfs_alert(log->l_mp, "xlog_space_left: head behind tail");
1238 xfs_alert(log->l_mp,
1239 " tail_cycle = %d, tail_bytes = %d",
1240 tail_cycle, tail_bytes);
1241 xfs_alert(log->l_mp,
1242 " GH cycle = %d, GH bytes = %d",
1243 head_cycle, head_bytes);
1245 free_bytes = log->l_logsize;
1253 struct work_struct *work)
1255 struct xlog_in_core *iclog =
1256 container_of(work, struct xlog_in_core, ic_end_io_work);
1257 struct xlog *log = iclog->ic_log;
1260 error = blk_status_to_errno(iclog->ic_bio.bi_status);
1262 /* treat writes with injected CRC errors as failed */
1263 if (iclog->ic_fail_crc)
1268 * Race to shutdown the filesystem if we see an error.
1270 if (XFS_TEST_ERROR(error, log->l_mp, XFS_ERRTAG_IODONE_IOERR)) {
1271 xfs_alert(log->l_mp, "log I/O error %d", error);
1272 xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
1275 xlog_state_done_syncing(iclog);
1276 bio_uninit(&iclog->ic_bio);
1279 * Drop the lock to signal that we are done. Nothing references the
1280 * iclog after this, so an unmount waiting on this lock can now tear it
1281 * down safely. As such, it is unsafe to reference the iclog after the
1282 * unlock as we could race with it being freed.
1284 up(&iclog->ic_sema);
1288 * Return size of each in-core log record buffer.
1290 * All machines get 8 x 32kB buffers by default, unless tuned otherwise.
1292 * If the filesystem blocksize is too large, we may need to choose a
1293 * larger size since the directory code currently logs entire blocks.
1296 xlog_get_iclog_buffer_size(
1297 struct xfs_mount *mp,
1300 if (mp->m_logbufs <= 0)
1301 mp->m_logbufs = XLOG_MAX_ICLOGS;
1302 if (mp->m_logbsize <= 0)
1303 mp->m_logbsize = XLOG_BIG_RECORD_BSIZE;
1305 log->l_iclog_bufs = mp->m_logbufs;
1306 log->l_iclog_size = mp->m_logbsize;
1309 * # headers = size / 32k - one header holds cycles from 32k of data.
1311 log->l_iclog_heads =
1312 DIV_ROUND_UP(mp->m_logbsize, XLOG_HEADER_CYCLE_SIZE);
1313 log->l_iclog_hsize = log->l_iclog_heads << BBSHIFT;
1318 struct xfs_mount *mp)
1320 queue_delayed_work(mp->m_sync_workqueue, &mp->m_log->l_work,
1321 msecs_to_jiffies(xfs_syncd_centisecs * 10));
1325 * Every sync period we need to unpin all items in the AIL and push them to
1326 * disk. If there is nothing dirty, then we might need to cover the log to
1327 * indicate that the filesystem is idle.
1331 struct work_struct *work)
1333 struct xlog *log = container_of(to_delayed_work(work),
1334 struct xlog, l_work);
1335 struct xfs_mount *mp = log->l_mp;
1337 /* dgc: errors ignored - not fatal and nowhere to report them */
1338 if (xfs_fs_writable(mp, SB_FREEZE_WRITE) && xfs_log_need_covered(mp)) {
1340 * Dump a transaction into the log that contains no real change.
1341 * This is needed to stamp the current tail LSN into the log
1342 * during the covering operation.
1344 * We cannot use an inode here for this - that will push dirty
1345 * state back up into the VFS and then periodic inode flushing
1346 * will prevent log covering from making progress. Hence we
1347 * synchronously log the superblock instead to ensure the
1348 * superblock is immediately unpinned and can be written back.
1350 xfs_sync_sb(mp, true);
1352 xfs_log_force(mp, 0);
1354 /* start pushing all the metadata that is currently dirty */
1355 xfs_ail_push_all(mp->m_ail);
1357 /* queue us up again */
1358 xfs_log_work_queue(mp);
1362 * This routine initializes some of the log structure for a given mount point.
1363 * Its primary purpose is to fill in enough, so recovery can occur. However,
1364 * some other stuff may be filled in too.
1366 STATIC struct xlog *
1368 struct xfs_mount *mp,
1369 struct xfs_buftarg *log_target,
1370 xfs_daddr_t blk_offset,
1374 xlog_rec_header_t *head;
1375 xlog_in_core_t **iclogp;
1376 xlog_in_core_t *iclog, *prev_iclog=NULL;
1378 int error = -ENOMEM;
1381 log = kmem_zalloc(sizeof(struct xlog), KM_MAYFAIL);
1383 xfs_warn(mp, "Log allocation failed: No memory!");
1388 log->l_targ = log_target;
1389 log->l_logsize = BBTOB(num_bblks);
1390 log->l_logBBstart = blk_offset;
1391 log->l_logBBsize = num_bblks;
1392 log->l_covered_state = XLOG_STATE_COVER_IDLE;
1393 log->l_flags |= XLOG_ACTIVE_RECOVERY;
1394 INIT_DELAYED_WORK(&log->l_work, xfs_log_worker);
1396 log->l_prev_block = -1;
1397 /* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */
1398 xlog_assign_atomic_lsn(&log->l_tail_lsn, 1, 0);
1399 xlog_assign_atomic_lsn(&log->l_last_sync_lsn, 1, 0);
1400 log->l_curr_cycle = 1; /* 0 is bad since this is initial value */
1402 xlog_grant_head_init(&log->l_reserve_head);
1403 xlog_grant_head_init(&log->l_write_head);
1405 error = -EFSCORRUPTED;
1406 if (xfs_sb_version_hassector(&mp->m_sb)) {
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);
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);
1421 /* for larger sector sizes, must have v2 or external log */
1422 if (log2_size && log->l_logBBstart > 0 &&
1423 !xfs_sb_version_haslogv2(&mp->m_sb)) {
1425 "log sector size (0x%x) invalid for configuration.",
1430 log->l_sectBBsize = 1 << log2_size;
1432 xlog_get_iclog_buffer_size(mp, log);
1434 spin_lock_init(&log->l_icloglock);
1435 init_waitqueue_head(&log->l_flush_wait);
1437 iclogp = &log->l_iclog;
1439 * The amount of memory to allocate for the iclog structure is
1440 * rather funky due to the way the structure is defined. It is
1441 * done this way so that we can use different sizes for machines
1442 * with different amounts of memory. See the definition of
1443 * xlog_in_core_t in xfs_log_priv.h for details.
1445 ASSERT(log->l_iclog_size >= 4096);
1446 for (i = 0; i < log->l_iclog_bufs; i++) {
1447 int align_mask = xfs_buftarg_dma_alignment(mp->m_logdev_targp);
1448 size_t bvec_size = howmany(log->l_iclog_size, PAGE_SIZE) *
1449 sizeof(struct bio_vec);
1451 iclog = kmem_zalloc(sizeof(*iclog) + bvec_size, KM_MAYFAIL);
1453 goto out_free_iclog;
1456 iclog->ic_prev = prev_iclog;
1459 iclog->ic_data = kmem_alloc_io(log->l_iclog_size, align_mask,
1460 KM_MAYFAIL | KM_ZERO);
1461 if (!iclog->ic_data)
1462 goto out_free_iclog;
1464 log->l_iclog_bak[i] = &iclog->ic_header;
1466 head = &iclog->ic_header;
1467 memset(head, 0, sizeof(xlog_rec_header_t));
1468 head->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);
1469 head->h_version = cpu_to_be32(
1470 xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1);
1471 head->h_size = cpu_to_be32(log->l_iclog_size);
1473 head->h_fmt = cpu_to_be32(XLOG_FMT);
1474 memcpy(&head->h_fs_uuid, &mp->m_sb.sb_uuid, sizeof(uuid_t));
1476 iclog->ic_size = log->l_iclog_size - log->l_iclog_hsize;
1477 iclog->ic_state = XLOG_STATE_ACTIVE;
1478 iclog->ic_log = log;
1479 atomic_set(&iclog->ic_refcnt, 0);
1480 spin_lock_init(&iclog->ic_callback_lock);
1481 INIT_LIST_HEAD(&iclog->ic_callbacks);
1482 iclog->ic_datap = (char *)iclog->ic_data + log->l_iclog_hsize;
1484 init_waitqueue_head(&iclog->ic_force_wait);
1485 init_waitqueue_head(&iclog->ic_write_wait);
1486 INIT_WORK(&iclog->ic_end_io_work, xlog_ioend_work);
1487 sema_init(&iclog->ic_sema, 1);
1489 iclogp = &iclog->ic_next;
1491 *iclogp = log->l_iclog; /* complete ring */
1492 log->l_iclog->ic_prev = prev_iclog; /* re-write 1st prev ptr */
1494 log->l_ioend_workqueue = alloc_workqueue("xfs-log/%s",
1495 XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM |
1497 0, mp->m_super->s_id);
1498 if (!log->l_ioend_workqueue)
1499 goto out_free_iclog;
1501 error = xlog_cil_init(log);
1503 goto out_destroy_workqueue;
1506 out_destroy_workqueue:
1507 destroy_workqueue(log->l_ioend_workqueue);
1509 for (iclog = log->l_iclog; iclog; iclog = prev_iclog) {
1510 prev_iclog = iclog->ic_next;
1511 kmem_free(iclog->ic_data);
1513 if (prev_iclog == log->l_iclog)
1519 return ERR_PTR(error);
1520 } /* xlog_alloc_log */
1523 * Write out the commit record of a transaction associated with the given
1524 * ticket to close off a running log write. Return the lsn of the commit record.
1529 struct xlog_ticket *ticket,
1530 struct xlog_in_core **iclog,
1533 struct xfs_log_iovec reg = {
1536 .i_type = XLOG_REG_TYPE_COMMIT,
1538 struct xfs_log_vec vec = {
1544 if (XLOG_FORCED_SHUTDOWN(log))
1547 error = xlog_write(log, &vec, ticket, lsn, iclog, XLOG_COMMIT_TRANS,
1550 xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
1555 * Compute the LSN that we'd need to push the log tail towards in order to have
1556 * (a) enough on-disk log space to log the number of bytes specified, (b) at
1557 * least 25% of the log space free, and (c) at least 256 blocks free. If the
1558 * log free space already meets all three thresholds, this function returns
1562 xlog_grant_push_threshold(
1566 xfs_lsn_t threshold_lsn = 0;
1567 xfs_lsn_t last_sync_lsn;
1570 int threshold_block;
1571 int threshold_cycle;
1574 ASSERT(BTOBB(need_bytes) < log->l_logBBsize);
1576 free_bytes = xlog_space_left(log, &log->l_reserve_head.grant);
1577 free_blocks = BTOBBT(free_bytes);
1580 * Set the threshold for the minimum number of free blocks in the
1581 * log to the maximum of what the caller needs, one quarter of the
1582 * log, and 256 blocks.
1584 free_threshold = BTOBB(need_bytes);
1585 free_threshold = max(free_threshold, (log->l_logBBsize >> 2));
1586 free_threshold = max(free_threshold, 256);
1587 if (free_blocks >= free_threshold)
1588 return NULLCOMMITLSN;
1590 xlog_crack_atomic_lsn(&log->l_tail_lsn, &threshold_cycle,
1592 threshold_block += free_threshold;
1593 if (threshold_block >= log->l_logBBsize) {
1594 threshold_block -= log->l_logBBsize;
1595 threshold_cycle += 1;
1597 threshold_lsn = xlog_assign_lsn(threshold_cycle,
1600 * Don't pass in an lsn greater than the lsn of the last
1601 * log record known to be on disk. Use a snapshot of the last sync lsn
1602 * so that it doesn't change between the compare and the set.
1604 last_sync_lsn = atomic64_read(&log->l_last_sync_lsn);
1605 if (XFS_LSN_CMP(threshold_lsn, last_sync_lsn) > 0)
1606 threshold_lsn = last_sync_lsn;
1608 return threshold_lsn;
1612 * Push the tail of the log if we need to do so to maintain the free log space
1613 * thresholds set out by xlog_grant_push_threshold. We may need to adopt a
1614 * policy which pushes on an lsn which is further along in the log once we
1615 * reach the high water mark. In this manner, we would be creating a low water
1619 xlog_grant_push_ail(
1623 xfs_lsn_t threshold_lsn;
1625 threshold_lsn = xlog_grant_push_threshold(log, need_bytes);
1626 if (threshold_lsn == NULLCOMMITLSN || XLOG_FORCED_SHUTDOWN(log))
1630 * Get the transaction layer to kick the dirty buffers out to
1631 * disk asynchronously. No point in trying to do this if
1632 * the filesystem is shutting down.
1634 xfs_ail_push(log->l_ailp, threshold_lsn);
1638 * Stamp cycle number in every block
1643 struct xlog_in_core *iclog,
1647 int size = iclog->ic_offset + roundoff;
1651 cycle_lsn = CYCLE_LSN_DISK(iclog->ic_header.h_lsn);
1653 dp = iclog->ic_datap;
1654 for (i = 0; i < BTOBB(size); i++) {
1655 if (i >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE))
1657 iclog->ic_header.h_cycle_data[i] = *(__be32 *)dp;
1658 *(__be32 *)dp = cycle_lsn;
1662 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
1663 xlog_in_core_2_t *xhdr = iclog->ic_data;
1665 for ( ; i < BTOBB(size); i++) {
1666 j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
1667 k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
1668 xhdr[j].hic_xheader.xh_cycle_data[k] = *(__be32 *)dp;
1669 *(__be32 *)dp = cycle_lsn;
1673 for (i = 1; i < log->l_iclog_heads; i++)
1674 xhdr[i].hic_xheader.xh_cycle = cycle_lsn;
1679 * Calculate the checksum for a log buffer.
1681 * This is a little more complicated than it should be because the various
1682 * headers and the actual data are non-contiguous.
1687 struct xlog_rec_header *rhead,
1693 /* first generate the crc for the record header ... */
1694 crc = xfs_start_cksum_update((char *)rhead,
1695 sizeof(struct xlog_rec_header),
1696 offsetof(struct xlog_rec_header, h_crc));
1698 /* ... then for additional cycle data for v2 logs ... */
1699 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
1700 union xlog_in_core2 *xhdr = (union xlog_in_core2 *)rhead;
1704 xheads = DIV_ROUND_UP(size, XLOG_HEADER_CYCLE_SIZE);
1706 for (i = 1; i < xheads; i++) {
1707 crc = crc32c(crc, &xhdr[i].hic_xheader,
1708 sizeof(struct xlog_rec_ext_header));
1712 /* ... and finally for the payload */
1713 crc = crc32c(crc, dp, size);
1715 return xfs_end_cksum(crc);
1722 struct xlog_in_core *iclog = bio->bi_private;
1724 queue_work(iclog->ic_log->l_ioend_workqueue,
1725 &iclog->ic_end_io_work);
1729 xlog_map_iclog_data(
1735 struct page *page = kmem_to_page(data);
1736 unsigned int off = offset_in_page(data);
1737 size_t len = min_t(size_t, count, PAGE_SIZE - off);
1739 if (bio_add_page(bio, page, len, off) != len)
1752 struct xlog_in_core *iclog,
1757 ASSERT(bno < log->l_logBBsize);
1760 * We lock the iclogbufs here so that we can serialise against I/O
1761 * completion during unmount. We might be processing a shutdown
1762 * triggered during unmount, and that can occur asynchronously to the
1763 * unmount thread, and hence we need to ensure that completes before
1764 * tearing down the iclogbufs. Hence we need to hold the buffer lock
1765 * across the log IO to archieve that.
1767 down(&iclog->ic_sema);
1768 if (unlikely(iclog->ic_state == XLOG_STATE_IOERROR)) {
1770 * It would seem logical to return EIO here, but we rely on
1771 * the log state machine to propagate I/O errors instead of
1772 * doing it here. We kick of the state machine and unlock
1773 * the buffer manually, the code needs to be kept in sync
1774 * with the I/O completion path.
1776 xlog_state_done_syncing(iclog);
1777 up(&iclog->ic_sema);
1781 bio_init(&iclog->ic_bio, iclog->ic_bvec, howmany(count, PAGE_SIZE));
1782 bio_set_dev(&iclog->ic_bio, log->l_targ->bt_bdev);
1783 iclog->ic_bio.bi_iter.bi_sector = log->l_logBBstart + bno;
1784 iclog->ic_bio.bi_end_io = xlog_bio_end_io;
1785 iclog->ic_bio.bi_private = iclog;
1788 * We use REQ_SYNC | REQ_IDLE here to tell the block layer the are more
1789 * IOs coming immediately after this one. This prevents the block layer
1790 * writeback throttle from throttling log writes behind background
1791 * metadata writeback and causing priority inversions.
1793 iclog->ic_bio.bi_opf = REQ_OP_WRITE | REQ_META | REQ_SYNC |
1796 iclog->ic_bio.bi_opf |= REQ_PREFLUSH;
1798 if (xlog_map_iclog_data(&iclog->ic_bio, iclog->ic_data, count)) {
1799 xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
1802 if (is_vmalloc_addr(iclog->ic_data))
1803 flush_kernel_vmap_range(iclog->ic_data, count);
1806 * If this log buffer would straddle the end of the log we will have
1807 * to split it up into two bios, so that we can continue at the start.
1809 if (bno + BTOBB(count) > log->l_logBBsize) {
1812 split = bio_split(&iclog->ic_bio, log->l_logBBsize - bno,
1813 GFP_NOIO, &fs_bio_set);
1814 bio_chain(split, &iclog->ic_bio);
1817 /* restart at logical offset zero for the remainder */
1818 iclog->ic_bio.bi_iter.bi_sector = log->l_logBBstart;
1821 submit_bio(&iclog->ic_bio);
1825 * We need to bump cycle number for the part of the iclog that is
1826 * written to the start of the log. Watch out for the header magic
1827 * number case, though.
1836 unsigned int split_offset = BBTOB(log->l_logBBsize - bno);
1839 for (i = split_offset; i < count; i += BBSIZE) {
1840 uint32_t cycle = get_unaligned_be32(data + i);
1842 if (++cycle == XLOG_HEADER_MAGIC_NUM)
1844 put_unaligned_be32(cycle, data + i);
1849 xlog_calc_iclog_size(
1851 struct xlog_in_core *iclog,
1854 uint32_t count_init, count;
1857 use_lsunit = xfs_sb_version_haslogv2(&log->l_mp->m_sb) &&
1858 log->l_mp->m_sb.sb_logsunit > 1;
1860 /* Add for LR header */
1861 count_init = log->l_iclog_hsize + iclog->ic_offset;
1863 /* Round out the log write size */
1865 /* we have a v2 stripe unit to use */
1866 count = XLOG_LSUNITTOB(log, XLOG_BTOLSUNIT(log, count_init));
1868 count = BBTOB(BTOBB(count_init));
1871 ASSERT(count >= count_init);
1872 *roundoff = count - count_init;
1875 ASSERT(*roundoff < log->l_mp->m_sb.sb_logsunit);
1877 ASSERT(*roundoff < BBTOB(1));
1882 * Flush out the in-core log (iclog) to the on-disk log in an asynchronous
1883 * fashion. Previously, we should have moved the current iclog
1884 * ptr in the log to point to the next available iclog. This allows further
1885 * write to continue while this code syncs out an iclog ready to go.
1886 * Before an in-core log can be written out, the data section must be scanned
1887 * to save away the 1st word of each BBSIZE block into the header. We replace
1888 * it with the current cycle count. Each BBSIZE block is tagged with the
1889 * cycle count because there in an implicit assumption that drives will
1890 * guarantee that entire 512 byte blocks get written at once. In other words,
1891 * we can't have part of a 512 byte block written and part not written. By
1892 * tagging each block, we will know which blocks are valid when recovering
1893 * after an unclean shutdown.
1895 * This routine is single threaded on the iclog. No other thread can be in
1896 * this routine with the same iclog. Changing contents of iclog can there-
1897 * fore be done without grabbing the state machine lock. Updating the global
1898 * log will require grabbing the lock though.
1900 * The entire log manager uses a logical block numbering scheme. Only
1901 * xlog_write_iclog knows about the fact that the log may not start with
1902 * block zero on a given device.
1907 struct xlog_in_core *iclog)
1909 unsigned int count; /* byte count of bwrite */
1910 unsigned int roundoff; /* roundoff to BB or stripe */
1913 bool need_flush = true, split = false;
1915 ASSERT(atomic_read(&iclog->ic_refcnt) == 0);
1917 count = xlog_calc_iclog_size(log, iclog, &roundoff);
1919 /* move grant heads by roundoff in sync */
1920 xlog_grant_add_space(log, &log->l_reserve_head.grant, roundoff);
1921 xlog_grant_add_space(log, &log->l_write_head.grant, roundoff);
1923 /* put cycle number in every block */
1924 xlog_pack_data(log, iclog, roundoff);
1926 /* real byte length */
1927 size = iclog->ic_offset;
1928 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb))
1930 iclog->ic_header.h_len = cpu_to_be32(size);
1932 XFS_STATS_INC(log->l_mp, xs_log_writes);
1933 XFS_STATS_ADD(log->l_mp, xs_log_blocks, BTOBB(count));
1935 bno = BLOCK_LSN(be64_to_cpu(iclog->ic_header.h_lsn));
1937 /* Do we need to split this write into 2 parts? */
1938 if (bno + BTOBB(count) > log->l_logBBsize) {
1939 xlog_split_iclog(log, &iclog->ic_header, bno, count);
1943 /* calculcate the checksum */
1944 iclog->ic_header.h_crc = xlog_cksum(log, &iclog->ic_header,
1945 iclog->ic_datap, size);
1947 * Intentionally corrupt the log record CRC based on the error injection
1948 * frequency, if defined. This facilitates testing log recovery in the
1949 * event of torn writes. Hence, set the IOABORT state to abort the log
1950 * write on I/O completion and shutdown the fs. The subsequent mount
1951 * detects the bad CRC and attempts to recover.
1954 if (XFS_TEST_ERROR(false, log->l_mp, XFS_ERRTAG_LOG_BAD_CRC)) {
1955 iclog->ic_header.h_crc &= cpu_to_le32(0xAAAAAAAA);
1956 iclog->ic_fail_crc = true;
1958 "Intentionally corrupted log record at LSN 0x%llx. Shutdown imminent.",
1959 be64_to_cpu(iclog->ic_header.h_lsn));
1964 * Flush the data device before flushing the log to make sure all meta
1965 * data written back from the AIL actually made it to disk before
1966 * stamping the new log tail LSN into the log buffer. For an external
1967 * log we need to issue the flush explicitly, and unfortunately
1968 * synchronously here; for an internal log we can simply use the block
1969 * layer state machine for preflushes.
1971 if (log->l_targ != log->l_mp->m_ddev_targp || split) {
1972 xfs_blkdev_issue_flush(log->l_mp->m_ddev_targp);
1976 xlog_verify_iclog(log, iclog, count);
1977 xlog_write_iclog(log, iclog, bno, count, need_flush);
1981 * Deallocate a log structure
1987 xlog_in_core_t *iclog, *next_iclog;
1990 xlog_cil_destroy(log);
1993 * Cycle all the iclogbuf locks to make sure all log IO completion
1994 * is done before we tear down these buffers.
1996 iclog = log->l_iclog;
1997 for (i = 0; i < log->l_iclog_bufs; i++) {
1998 down(&iclog->ic_sema);
1999 up(&iclog->ic_sema);
2000 iclog = iclog->ic_next;
2003 iclog = log->l_iclog;
2004 for (i = 0; i < log->l_iclog_bufs; i++) {
2005 next_iclog = iclog->ic_next;
2006 kmem_free(iclog->ic_data);
2011 log->l_mp->m_log = NULL;
2012 destroy_workqueue(log->l_ioend_workqueue);
2017 * Update counters atomically now that memcpy is done.
2020 xlog_state_finish_copy(
2022 struct xlog_in_core *iclog,
2026 lockdep_assert_held(&log->l_icloglock);
2028 be32_add_cpu(&iclog->ic_header.h_num_logops, record_cnt);
2029 iclog->ic_offset += copy_bytes;
2033 * print out info relating to regions written which consume
2038 struct xfs_mount *mp,
2039 struct xlog_ticket *ticket)
2042 uint ophdr_spc = ticket->t_res_num_ophdrs * (uint)sizeof(xlog_op_header_t);
2044 /* match with XLOG_REG_TYPE_* in xfs_log.h */
2045 #define REG_TYPE_STR(type, str) [XLOG_REG_TYPE_##type] = str
2046 static char *res_type_str[] = {
2047 REG_TYPE_STR(BFORMAT, "bformat"),
2048 REG_TYPE_STR(BCHUNK, "bchunk"),
2049 REG_TYPE_STR(EFI_FORMAT, "efi_format"),
2050 REG_TYPE_STR(EFD_FORMAT, "efd_format"),
2051 REG_TYPE_STR(IFORMAT, "iformat"),
2052 REG_TYPE_STR(ICORE, "icore"),
2053 REG_TYPE_STR(IEXT, "iext"),
2054 REG_TYPE_STR(IBROOT, "ibroot"),
2055 REG_TYPE_STR(ILOCAL, "ilocal"),
2056 REG_TYPE_STR(IATTR_EXT, "iattr_ext"),
2057 REG_TYPE_STR(IATTR_BROOT, "iattr_broot"),
2058 REG_TYPE_STR(IATTR_LOCAL, "iattr_local"),
2059 REG_TYPE_STR(QFORMAT, "qformat"),
2060 REG_TYPE_STR(DQUOT, "dquot"),
2061 REG_TYPE_STR(QUOTAOFF, "quotaoff"),
2062 REG_TYPE_STR(LRHEADER, "LR header"),
2063 REG_TYPE_STR(UNMOUNT, "unmount"),
2064 REG_TYPE_STR(COMMIT, "commit"),
2065 REG_TYPE_STR(TRANSHDR, "trans header"),
2066 REG_TYPE_STR(ICREATE, "inode create"),
2067 REG_TYPE_STR(RUI_FORMAT, "rui_format"),
2068 REG_TYPE_STR(RUD_FORMAT, "rud_format"),
2069 REG_TYPE_STR(CUI_FORMAT, "cui_format"),
2070 REG_TYPE_STR(CUD_FORMAT, "cud_format"),
2071 REG_TYPE_STR(BUI_FORMAT, "bui_format"),
2072 REG_TYPE_STR(BUD_FORMAT, "bud_format"),
2074 BUILD_BUG_ON(ARRAY_SIZE(res_type_str) != XLOG_REG_TYPE_MAX + 1);
2077 xfs_warn(mp, "ticket reservation summary:");
2078 xfs_warn(mp, " unit res = %d bytes",
2079 ticket->t_unit_res);
2080 xfs_warn(mp, " current res = %d bytes",
2081 ticket->t_curr_res);
2082 xfs_warn(mp, " total reg = %u bytes (o/flow = %u bytes)",
2083 ticket->t_res_arr_sum, ticket->t_res_o_flow);
2084 xfs_warn(mp, " ophdrs = %u (ophdr space = %u bytes)",
2085 ticket->t_res_num_ophdrs, ophdr_spc);
2086 xfs_warn(mp, " ophdr + reg = %u bytes",
2087 ticket->t_res_arr_sum + ticket->t_res_o_flow + ophdr_spc);
2088 xfs_warn(mp, " num regions = %u",
2091 for (i = 0; i < ticket->t_res_num; i++) {
2092 uint r_type = ticket->t_res_arr[i].r_type;
2093 xfs_warn(mp, "region[%u]: %s - %u bytes", i,
2094 ((r_type <= 0 || r_type > XLOG_REG_TYPE_MAX) ?
2095 "bad-rtype" : res_type_str[r_type]),
2096 ticket->t_res_arr[i].r_len);
2101 * Print a summary of the transaction.
2105 struct xfs_trans *tp)
2107 struct xfs_mount *mp = tp->t_mountp;
2108 struct xfs_log_item *lip;
2110 /* dump core transaction and ticket info */
2111 xfs_warn(mp, "transaction summary:");
2112 xfs_warn(mp, " log res = %d", tp->t_log_res);
2113 xfs_warn(mp, " log count = %d", tp->t_log_count);
2114 xfs_warn(mp, " flags = 0x%x", tp->t_flags);
2116 xlog_print_tic_res(mp, tp->t_ticket);
2118 /* dump each log item */
2119 list_for_each_entry(lip, &tp->t_items, li_trans) {
2120 struct xfs_log_vec *lv = lip->li_lv;
2121 struct xfs_log_iovec *vec;
2124 xfs_warn(mp, "log item: ");
2125 xfs_warn(mp, " type = 0x%x", lip->li_type);
2126 xfs_warn(mp, " flags = 0x%lx", lip->li_flags);
2129 xfs_warn(mp, " niovecs = %d", lv->lv_niovecs);
2130 xfs_warn(mp, " size = %d", lv->lv_size);
2131 xfs_warn(mp, " bytes = %d", lv->lv_bytes);
2132 xfs_warn(mp, " buf len = %d", lv->lv_buf_len);
2134 /* dump each iovec for the log item */
2135 vec = lv->lv_iovecp;
2136 for (i = 0; i < lv->lv_niovecs; i++) {
2137 int dumplen = min(vec->i_len, 32);
2139 xfs_warn(mp, " iovec[%d]", i);
2140 xfs_warn(mp, " type = 0x%x", vec->i_type);
2141 xfs_warn(mp, " len = %d", vec->i_len);
2142 xfs_warn(mp, " first %d bytes of iovec[%d]:", dumplen, i);
2143 xfs_hex_dump(vec->i_addr, dumplen);
2151 * Calculate the potential space needed by the log vector. We may need a start
2152 * record, and each region gets its own struct xlog_op_header and may need to be
2153 * double word aligned.
2156 xlog_write_calc_vec_length(
2157 struct xlog_ticket *ticket,
2158 struct xfs_log_vec *log_vector,
2159 bool need_start_rec)
2161 struct xfs_log_vec *lv;
2162 int headers = need_start_rec ? 1 : 0;
2166 for (lv = log_vector; lv; lv = lv->lv_next) {
2167 /* we don't write ordered log vectors */
2168 if (lv->lv_buf_len == XFS_LOG_VEC_ORDERED)
2171 headers += lv->lv_niovecs;
2173 for (i = 0; i < lv->lv_niovecs; i++) {
2174 struct xfs_log_iovec *vecp = &lv->lv_iovecp[i];
2177 xlog_tic_add_region(ticket, vecp->i_len, vecp->i_type);
2181 ticket->t_res_num_ophdrs += headers;
2182 len += headers * sizeof(struct xlog_op_header);
2188 xlog_write_start_rec(
2189 struct xlog_op_header *ophdr,
2190 struct xlog_ticket *ticket)
2192 ophdr->oh_tid = cpu_to_be32(ticket->t_tid);
2193 ophdr->oh_clientid = ticket->t_clientid;
2195 ophdr->oh_flags = XLOG_START_TRANS;
2199 static xlog_op_header_t *
2200 xlog_write_setup_ophdr(
2202 struct xlog_op_header *ophdr,
2203 struct xlog_ticket *ticket,
2206 ophdr->oh_tid = cpu_to_be32(ticket->t_tid);
2207 ophdr->oh_clientid = ticket->t_clientid;
2210 /* are we copying a commit or unmount record? */
2211 ophdr->oh_flags = flags;
2214 * We've seen logs corrupted with bad transaction client ids. This
2215 * makes sure that XFS doesn't generate them on. Turn this into an EIO
2216 * and shut down the filesystem.
2218 switch (ophdr->oh_clientid) {
2219 case XFS_TRANSACTION:
2225 "Bad XFS transaction clientid 0x%x in ticket "PTR_FMT,
2226 ophdr->oh_clientid, ticket);
2234 * Set up the parameters of the region copy into the log. This has
2235 * to handle region write split across multiple log buffers - this
2236 * state is kept external to this function so that this code can
2237 * be written in an obvious, self documenting manner.
2240 xlog_write_setup_copy(
2241 struct xlog_ticket *ticket,
2242 struct xlog_op_header *ophdr,
2243 int space_available,
2247 int *last_was_partial_copy,
2248 int *bytes_consumed)
2252 still_to_copy = space_required - *bytes_consumed;
2253 *copy_off = *bytes_consumed;
2255 if (still_to_copy <= space_available) {
2256 /* write of region completes here */
2257 *copy_len = still_to_copy;
2258 ophdr->oh_len = cpu_to_be32(*copy_len);
2259 if (*last_was_partial_copy)
2260 ophdr->oh_flags |= (XLOG_END_TRANS|XLOG_WAS_CONT_TRANS);
2261 *last_was_partial_copy = 0;
2262 *bytes_consumed = 0;
2266 /* partial write of region, needs extra log op header reservation */
2267 *copy_len = space_available;
2268 ophdr->oh_len = cpu_to_be32(*copy_len);
2269 ophdr->oh_flags |= XLOG_CONTINUE_TRANS;
2270 if (*last_was_partial_copy)
2271 ophdr->oh_flags |= XLOG_WAS_CONT_TRANS;
2272 *bytes_consumed += *copy_len;
2273 (*last_was_partial_copy)++;
2275 /* account for new log op header */
2276 ticket->t_curr_res -= sizeof(struct xlog_op_header);
2277 ticket->t_res_num_ophdrs++;
2279 return sizeof(struct xlog_op_header);
2283 xlog_write_copy_finish(
2285 struct xlog_in_core *iclog,
2290 int *partial_copy_len,
2292 struct xlog_in_core **commit_iclog)
2296 if (*partial_copy) {
2298 * This iclog has already been marked WANT_SYNC by
2299 * xlog_state_get_iclog_space.
2301 spin_lock(&log->l_icloglock);
2302 xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt);
2309 *partial_copy_len = 0;
2311 if (iclog->ic_size - log_offset <= sizeof(xlog_op_header_t)) {
2312 /* no more space in this iclog - push it. */
2313 spin_lock(&log->l_icloglock);
2314 xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt);
2318 if (iclog->ic_state == XLOG_STATE_ACTIVE)
2319 xlog_state_switch_iclogs(log, iclog, 0);
2321 ASSERT(iclog->ic_state == XLOG_STATE_WANT_SYNC ||
2322 iclog->ic_state == XLOG_STATE_IOERROR);
2325 spin_unlock(&log->l_icloglock);
2326 ASSERT(flags & XLOG_COMMIT_TRANS);
2327 *commit_iclog = iclog;
2333 error = xlog_state_release_iclog(log, iclog);
2334 spin_unlock(&log->l_icloglock);
2339 * Write some region out to in-core log
2341 * This will be called when writing externally provided regions or when
2342 * writing out a commit record for a given transaction.
2344 * General algorithm:
2345 * 1. Find total length of this write. This may include adding to the
2346 * lengths passed in.
2347 * 2. Check whether we violate the tickets reservation.
2348 * 3. While writing to this iclog
2349 * A. Reserve as much space in this iclog as can get
2350 * B. If this is first write, save away start lsn
2351 * C. While writing this region:
2352 * 1. If first write of transaction, write start record
2353 * 2. Write log operation header (header per region)
2354 * 3. Find out if we can fit entire region into this iclog
2355 * 4. Potentially, verify destination memcpy ptr
2356 * 5. Memcpy (partial) region
2357 * 6. If partial copy, release iclog; otherwise, continue
2358 * copying more regions into current iclog
2359 * 4. Mark want sync bit (in simulation mode)
2360 * 5. Release iclog for potential flush to on-disk log.
2363 * 1. Panic if reservation is overrun. This should never happen since
2364 * reservation amounts are generated internal to the filesystem.
2366 * 1. Tickets are single threaded data structures.
2367 * 2. The XLOG_END_TRANS & XLOG_CONTINUE_TRANS flags are passed down to the
2368 * syncing routine. When a single log_write region needs to span
2369 * multiple in-core logs, the XLOG_CONTINUE_TRANS bit should be set
2370 * on all log operation writes which don't contain the end of the
2371 * region. The XLOG_END_TRANS bit is used for the in-core log
2372 * operation which contains the end of the continued log_write region.
2373 * 3. When xlog_state_get_iclog_space() grabs the rest of the current iclog,
2374 * we don't really know exactly how much space will be used. As a result,
2375 * we don't update ic_offset until the end when we know exactly how many
2376 * bytes have been written out.
2381 struct xfs_log_vec *log_vector,
2382 struct xlog_ticket *ticket,
2383 xfs_lsn_t *start_lsn,
2384 struct xlog_in_core **commit_iclog,
2386 bool need_start_rec)
2388 struct xlog_in_core *iclog = NULL;
2389 struct xfs_log_vec *lv = log_vector;
2390 struct xfs_log_iovec *vecp = lv->lv_iovecp;
2393 int partial_copy = 0;
2394 int partial_copy_len = 0;
2401 * If this is a commit or unmount transaction, we don't need a start
2402 * record to be written. We do, however, have to account for the
2403 * commit or unmount header that gets written. Hence we always have
2404 * to account for an extra xlog_op_header here.
2406 ticket->t_curr_res -= sizeof(struct xlog_op_header);
2407 if (ticket->t_curr_res < 0) {
2408 xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES,
2409 "ctx ticket reservation ran out. Need to up reservation");
2410 xlog_print_tic_res(log->l_mp, ticket);
2411 xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
2414 len = xlog_write_calc_vec_length(ticket, log_vector, need_start_rec);
2416 while (lv && (!lv->lv_niovecs || index < lv->lv_niovecs)) {
2420 error = xlog_state_get_iclog_space(log, len, &iclog, ticket,
2421 &contwr, &log_offset);
2425 ASSERT(log_offset <= iclog->ic_size - 1);
2426 ptr = iclog->ic_datap + log_offset;
2428 /* start_lsn is the first lsn written to. That's all we need. */
2430 *start_lsn = be64_to_cpu(iclog->ic_header.h_lsn);
2433 * This loop writes out as many regions as can fit in the amount
2434 * of space which was allocated by xlog_state_get_iclog_space().
2436 while (lv && (!lv->lv_niovecs || index < lv->lv_niovecs)) {
2437 struct xfs_log_iovec *reg;
2438 struct xlog_op_header *ophdr;
2441 bool ordered = false;
2443 /* ordered log vectors have no regions to write */
2444 if (lv->lv_buf_len == XFS_LOG_VEC_ORDERED) {
2445 ASSERT(lv->lv_niovecs == 0);
2451 ASSERT(reg->i_len % sizeof(int32_t) == 0);
2452 ASSERT((unsigned long)ptr % sizeof(int32_t) == 0);
2455 * Before we start formatting log vectors, we need to
2456 * write a start record. Only do this for the first
2457 * iclog we write to.
2459 if (need_start_rec) {
2460 xlog_write_start_rec(ptr, ticket);
2461 xlog_write_adv_cnt(&ptr, &len, &log_offset,
2462 sizeof(struct xlog_op_header));
2465 ophdr = xlog_write_setup_ophdr(log, ptr, ticket, flags);
2469 xlog_write_adv_cnt(&ptr, &len, &log_offset,
2470 sizeof(struct xlog_op_header));
2472 len += xlog_write_setup_copy(ticket, ophdr,
2473 iclog->ic_size-log_offset,
2475 ©_off, ©_len,
2478 xlog_verify_dest_ptr(log, ptr);
2483 * Unmount records just log an opheader, so can have
2484 * empty payloads with no data region to copy. Hence we
2485 * only copy the payload if the vector says it has data
2488 ASSERT(copy_len >= 0);
2490 memcpy(ptr, reg->i_addr + copy_off, copy_len);
2491 xlog_write_adv_cnt(&ptr, &len, &log_offset,
2494 copy_len += sizeof(struct xlog_op_header);
2496 if (need_start_rec) {
2497 copy_len += sizeof(struct xlog_op_header);
2499 need_start_rec = false;
2501 data_cnt += contwr ? copy_len : 0;
2503 error = xlog_write_copy_finish(log, iclog, flags,
2504 &record_cnt, &data_cnt,
2513 * if we had a partial copy, we need to get more iclog
2514 * space but we don't want to increment the region
2515 * index because there is still more is this region to
2518 * If we completed writing this region, and we flushed
2519 * the iclog (indicated by resetting of the record
2520 * count), then we also need to get more log space. If
2521 * this was the last record, though, we are done and
2527 if (++index == lv->lv_niovecs) {
2532 vecp = lv->lv_iovecp;
2534 if (record_cnt == 0 && !ordered) {
2544 spin_lock(&log->l_icloglock);
2545 xlog_state_finish_copy(log, iclog, record_cnt, data_cnt);
2547 ASSERT(flags & XLOG_COMMIT_TRANS);
2548 *commit_iclog = iclog;
2550 error = xlog_state_release_iclog(log, iclog);
2552 spin_unlock(&log->l_icloglock);
2558 xlog_state_activate_iclog(
2559 struct xlog_in_core *iclog,
2560 int *iclogs_changed)
2562 ASSERT(list_empty_careful(&iclog->ic_callbacks));
2565 * If the number of ops in this iclog indicate it just contains the
2566 * dummy transaction, we can change state into IDLE (the second time
2567 * around). Otherwise we should change the state into NEED a dummy.
2568 * We don't need to cover the dummy.
2570 if (*iclogs_changed == 0 &&
2571 iclog->ic_header.h_num_logops == cpu_to_be32(XLOG_COVER_OPS)) {
2572 *iclogs_changed = 1;
2575 * We have two dirty iclogs so start over. This could also be
2576 * num of ops indicating this is not the dummy going out.
2578 *iclogs_changed = 2;
2581 iclog->ic_state = XLOG_STATE_ACTIVE;
2582 iclog->ic_offset = 0;
2583 iclog->ic_header.h_num_logops = 0;
2584 memset(iclog->ic_header.h_cycle_data, 0,
2585 sizeof(iclog->ic_header.h_cycle_data));
2586 iclog->ic_header.h_lsn = 0;
2590 * Loop through all iclogs and mark all iclogs currently marked DIRTY as
2591 * ACTIVE after iclog I/O has completed.
2594 xlog_state_activate_iclogs(
2596 int *iclogs_changed)
2598 struct xlog_in_core *iclog = log->l_iclog;
2601 if (iclog->ic_state == XLOG_STATE_DIRTY)
2602 xlog_state_activate_iclog(iclog, iclogs_changed);
2604 * The ordering of marking iclogs ACTIVE must be maintained, so
2605 * an iclog doesn't become ACTIVE beyond one that is SYNCING.
2607 else if (iclog->ic_state != XLOG_STATE_ACTIVE)
2609 } while ((iclog = iclog->ic_next) != log->l_iclog);
2618 * We go to NEED for any non-covering writes. We go to NEED2 if we just
2619 * wrote the first covering record (DONE). We go to IDLE if we just
2620 * wrote the second covering record (DONE2) and remain in IDLE until a
2621 * non-covering write occurs.
2623 switch (prev_state) {
2624 case XLOG_STATE_COVER_IDLE:
2625 if (iclogs_changed == 1)
2626 return XLOG_STATE_COVER_IDLE;
2627 case XLOG_STATE_COVER_NEED:
2628 case XLOG_STATE_COVER_NEED2:
2630 case XLOG_STATE_COVER_DONE:
2631 if (iclogs_changed == 1)
2632 return XLOG_STATE_COVER_NEED2;
2634 case XLOG_STATE_COVER_DONE2:
2635 if (iclogs_changed == 1)
2636 return XLOG_STATE_COVER_IDLE;
2642 return XLOG_STATE_COVER_NEED;
2646 xlog_state_clean_iclog(
2648 struct xlog_in_core *dirty_iclog)
2650 int iclogs_changed = 0;
2652 dirty_iclog->ic_state = XLOG_STATE_DIRTY;
2654 xlog_state_activate_iclogs(log, &iclogs_changed);
2655 wake_up_all(&dirty_iclog->ic_force_wait);
2657 if (iclogs_changed) {
2658 log->l_covered_state = xlog_covered_state(log->l_covered_state,
2664 xlog_get_lowest_lsn(
2667 struct xlog_in_core *iclog = log->l_iclog;
2668 xfs_lsn_t lowest_lsn = 0, lsn;
2671 if (iclog->ic_state == XLOG_STATE_ACTIVE ||
2672 iclog->ic_state == XLOG_STATE_DIRTY)
2675 lsn = be64_to_cpu(iclog->ic_header.h_lsn);
2676 if ((lsn && !lowest_lsn) || XFS_LSN_CMP(lsn, lowest_lsn) < 0)
2678 } while ((iclog = iclog->ic_next) != log->l_iclog);
2684 * Completion of a iclog IO does not imply that a transaction has completed, as
2685 * transactions can be large enough to span many iclogs. We cannot change the
2686 * tail of the log half way through a transaction as this may be the only
2687 * transaction in the log and moving the tail to point to the middle of it
2688 * will prevent recovery from finding the start of the transaction. Hence we
2689 * should only update the last_sync_lsn if this iclog contains transaction
2690 * completion callbacks on it.
2692 * We have to do this before we drop the icloglock to ensure we are the only one
2693 * that can update it.
2695 * If we are moving the last_sync_lsn forwards, we also need to ensure we kick
2696 * the reservation grant head pushing. This is due to the fact that the push
2697 * target is bound by the current last_sync_lsn value. Hence if we have a large
2698 * amount of log space bound up in this committing transaction then the
2699 * last_sync_lsn value may be the limiting factor preventing tail pushing from
2700 * freeing space in the log. Hence once we've updated the last_sync_lsn we
2701 * should push the AIL to ensure the push target (and hence the grant head) is
2702 * no longer bound by the old log head location and can move forwards and make
2706 xlog_state_set_callback(
2708 struct xlog_in_core *iclog,
2709 xfs_lsn_t header_lsn)
2711 iclog->ic_state = XLOG_STATE_CALLBACK;
2713 ASSERT(XFS_LSN_CMP(atomic64_read(&log->l_last_sync_lsn),
2716 if (list_empty_careful(&iclog->ic_callbacks))
2719 atomic64_set(&log->l_last_sync_lsn, header_lsn);
2720 xlog_grant_push_ail(log, 0);
2724 * Return true if we need to stop processing, false to continue to the next
2725 * iclog. The caller will need to run callbacks if the iclog is returned in the
2726 * XLOG_STATE_CALLBACK state.
2729 xlog_state_iodone_process_iclog(
2731 struct xlog_in_core *iclog,
2734 xfs_lsn_t lowest_lsn;
2735 xfs_lsn_t header_lsn;
2737 switch (iclog->ic_state) {
2738 case XLOG_STATE_ACTIVE:
2739 case XLOG_STATE_DIRTY:
2741 * Skip all iclogs in the ACTIVE & DIRTY states:
2744 case XLOG_STATE_IOERROR:
2746 * Between marking a filesystem SHUTDOWN and stopping the log,
2747 * we do flush all iclogs to disk (if there wasn't a log I/O
2748 * error). So, we do want things to go smoothly in case of just
2749 * a SHUTDOWN w/o a LOG_IO_ERROR.
2753 case XLOG_STATE_DONE_SYNC:
2755 * Now that we have an iclog that is in the DONE_SYNC state, do
2756 * one more check here to see if we have chased our tail around.
2757 * If this is not the lowest lsn iclog, then we will leave it
2758 * for another completion to process.
2760 header_lsn = be64_to_cpu(iclog->ic_header.h_lsn);
2761 lowest_lsn = xlog_get_lowest_lsn(log);
2762 if (lowest_lsn && XFS_LSN_CMP(lowest_lsn, header_lsn) < 0)
2764 xlog_state_set_callback(log, iclog, header_lsn);
2768 * Can only perform callbacks in order. Since this iclog is not
2769 * in the DONE_SYNC state, we skip the rest and just try to
2777 * Keep processing entries in the iclog callback list until we come around and
2778 * it is empty. We need to atomically see that the list is empty and change the
2779 * state to DIRTY so that we don't miss any more callbacks being added.
2781 * This function is called with the icloglock held and returns with it held. We
2782 * drop it while running callbacks, however, as holding it over thousands of
2783 * callbacks is unnecessary and causes excessive contention if we do.
2786 xlog_state_do_iclog_callbacks(
2788 struct xlog_in_core *iclog)
2789 __releases(&log->l_icloglock)
2790 __acquires(&log->l_icloglock)
2792 spin_unlock(&log->l_icloglock);
2793 spin_lock(&iclog->ic_callback_lock);
2794 while (!list_empty(&iclog->ic_callbacks)) {
2797 list_splice_init(&iclog->ic_callbacks, &tmp);
2799 spin_unlock(&iclog->ic_callback_lock);
2800 xlog_cil_process_committed(&tmp);
2801 spin_lock(&iclog->ic_callback_lock);
2805 * Pick up the icloglock while still holding the callback lock so we
2806 * serialise against anyone trying to add more callbacks to this iclog
2807 * now we've finished processing.
2809 spin_lock(&log->l_icloglock);
2810 spin_unlock(&iclog->ic_callback_lock);
2814 xlog_state_do_callback(
2817 struct xlog_in_core *iclog;
2818 struct xlog_in_core *first_iclog;
2819 bool cycled_icloglock;
2824 spin_lock(&log->l_icloglock);
2827 * Scan all iclogs starting with the one pointed to by the
2828 * log. Reset this starting point each time the log is
2829 * unlocked (during callbacks).
2831 * Keep looping through iclogs until one full pass is made
2832 * without running any callbacks.
2834 first_iclog = log->l_iclog;
2835 iclog = log->l_iclog;
2836 cycled_icloglock = false;
2841 if (xlog_state_iodone_process_iclog(log, iclog,
2845 if (iclog->ic_state != XLOG_STATE_CALLBACK &&
2846 iclog->ic_state != XLOG_STATE_IOERROR) {
2847 iclog = iclog->ic_next;
2852 * Running callbacks will drop the icloglock which means
2853 * we'll have to run at least one more complete loop.
2855 cycled_icloglock = true;
2856 xlog_state_do_iclog_callbacks(log, iclog);
2857 if (XLOG_FORCED_SHUTDOWN(log))
2858 wake_up_all(&iclog->ic_force_wait);
2860 xlog_state_clean_iclog(log, iclog);
2861 iclog = iclog->ic_next;
2862 } while (first_iclog != iclog);
2864 if (repeats > 5000) {
2865 flushcnt += repeats;
2868 "%s: possible infinite loop (%d iterations)",
2869 __func__, flushcnt);
2871 } while (!ioerror && cycled_icloglock);
2873 if (log->l_iclog->ic_state == XLOG_STATE_ACTIVE ||
2874 log->l_iclog->ic_state == XLOG_STATE_IOERROR)
2875 wake_up_all(&log->l_flush_wait);
2877 spin_unlock(&log->l_icloglock);
2882 * Finish transitioning this iclog to the dirty state.
2884 * Make sure that we completely execute this routine only when this is
2885 * the last call to the iclog. There is a good chance that iclog flushes,
2886 * when we reach the end of the physical log, get turned into 2 separate
2887 * calls to bwrite. Hence, one iclog flush could generate two calls to this
2888 * routine. By using the reference count bwritecnt, we guarantee that only
2889 * the second completion goes through.
2891 * Callbacks could take time, so they are done outside the scope of the
2892 * global state machine log lock.
2895 xlog_state_done_syncing(
2896 struct xlog_in_core *iclog)
2898 struct xlog *log = iclog->ic_log;
2900 spin_lock(&log->l_icloglock);
2901 ASSERT(atomic_read(&iclog->ic_refcnt) == 0);
2904 * If we got an error, either on the first buffer, or in the case of
2905 * split log writes, on the second, we shut down the file system and
2906 * no iclogs should ever be attempted to be written to disk again.
2908 if (!XLOG_FORCED_SHUTDOWN(log)) {
2909 ASSERT(iclog->ic_state == XLOG_STATE_SYNCING);
2910 iclog->ic_state = XLOG_STATE_DONE_SYNC;
2914 * Someone could be sleeping prior to writing out the next
2915 * iclog buffer, we wake them all, one will get to do the
2916 * I/O, the others get to wait for the result.
2918 wake_up_all(&iclog->ic_write_wait);
2919 spin_unlock(&log->l_icloglock);
2920 xlog_state_do_callback(log);
2924 * If the head of the in-core log ring is not (ACTIVE or DIRTY), then we must
2925 * sleep. We wait on the flush queue on the head iclog as that should be
2926 * the first iclog to complete flushing. Hence if all iclogs are syncing,
2927 * we will wait here and all new writes will sleep until a sync completes.
2929 * The in-core logs are used in a circular fashion. They are not used
2930 * out-of-order even when an iclog past the head is free.
2933 * * log_offset where xlog_write() can start writing into the in-core
2935 * * in-core log pointer to which xlog_write() should write.
2936 * * boolean indicating this is a continued write to an in-core log.
2937 * If this is the last write, then the in-core log's offset field
2938 * needs to be incremented, depending on the amount of data which
2942 xlog_state_get_iclog_space(
2945 struct xlog_in_core **iclogp,
2946 struct xlog_ticket *ticket,
2947 int *continued_write,
2951 xlog_rec_header_t *head;
2952 xlog_in_core_t *iclog;
2955 spin_lock(&log->l_icloglock);
2956 if (XLOG_FORCED_SHUTDOWN(log)) {
2957 spin_unlock(&log->l_icloglock);
2961 iclog = log->l_iclog;
2962 if (iclog->ic_state != XLOG_STATE_ACTIVE) {
2963 XFS_STATS_INC(log->l_mp, xs_log_noiclogs);
2965 /* Wait for log writes to have flushed */
2966 xlog_wait(&log->l_flush_wait, &log->l_icloglock);
2970 head = &iclog->ic_header;
2972 atomic_inc(&iclog->ic_refcnt); /* prevents sync */
2973 log_offset = iclog->ic_offset;
2975 /* On the 1st write to an iclog, figure out lsn. This works
2976 * if iclogs marked XLOG_STATE_WANT_SYNC always write out what they are
2977 * committing to. If the offset is set, that's how many blocks
2980 if (log_offset == 0) {
2981 ticket->t_curr_res -= log->l_iclog_hsize;
2982 xlog_tic_add_region(ticket,
2984 XLOG_REG_TYPE_LRHEADER);
2985 head->h_cycle = cpu_to_be32(log->l_curr_cycle);
2986 head->h_lsn = cpu_to_be64(
2987 xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block));
2988 ASSERT(log->l_curr_block >= 0);
2991 /* If there is enough room to write everything, then do it. Otherwise,
2992 * claim the rest of the region and make sure the XLOG_STATE_WANT_SYNC
2993 * bit is on, so this will get flushed out. Don't update ic_offset
2994 * until you know exactly how many bytes get copied. Therefore, wait
2995 * until later to update ic_offset.
2997 * xlog_write() algorithm assumes that at least 2 xlog_op_header_t's
2998 * can fit into remaining data section.
3000 if (iclog->ic_size - iclog->ic_offset < 2*sizeof(xlog_op_header_t)) {
3003 xlog_state_switch_iclogs(log, iclog, iclog->ic_size);
3006 * If we are the only one writing to this iclog, sync it to
3007 * disk. We need to do an atomic compare and decrement here to
3008 * avoid racing with concurrent atomic_dec_and_lock() calls in
3009 * xlog_state_release_iclog() when there is more than one
3010 * reference to the iclog.
3012 if (!atomic_add_unless(&iclog->ic_refcnt, -1, 1))
3013 error = xlog_state_release_iclog(log, iclog);
3014 spin_unlock(&log->l_icloglock);
3020 /* Do we have enough room to write the full amount in the remainder
3021 * of this iclog? Or must we continue a write on the next iclog and
3022 * mark this iclog as completely taken? In the case where we switch
3023 * iclogs (to mark it taken), this particular iclog will release/sync
3024 * to disk in xlog_write().
3026 if (len <= iclog->ic_size - iclog->ic_offset) {
3027 *continued_write = 0;
3028 iclog->ic_offset += len;
3030 *continued_write = 1;
3031 xlog_state_switch_iclogs(log, iclog, iclog->ic_size);
3035 ASSERT(iclog->ic_offset <= iclog->ic_size);
3036 spin_unlock(&log->l_icloglock);
3038 *logoffsetp = log_offset;
3043 * The first cnt-1 times a ticket goes through here we don't need to move the
3044 * grant write head because the permanent reservation has reserved cnt times the
3045 * unit amount. Release part of current permanent unit reservation and reset
3046 * current reservation to be one units worth. Also move grant reservation head
3050 xfs_log_ticket_regrant(
3052 struct xlog_ticket *ticket)
3054 trace_xfs_log_ticket_regrant(log, ticket);
3056 if (ticket->t_cnt > 0)
3059 xlog_grant_sub_space(log, &log->l_reserve_head.grant,
3060 ticket->t_curr_res);
3061 xlog_grant_sub_space(log, &log->l_write_head.grant,
3062 ticket->t_curr_res);
3063 ticket->t_curr_res = ticket->t_unit_res;
3064 xlog_tic_reset_res(ticket);
3066 trace_xfs_log_ticket_regrant_sub(log, ticket);
3068 /* just return if we still have some of the pre-reserved space */
3069 if (!ticket->t_cnt) {
3070 xlog_grant_add_space(log, &log->l_reserve_head.grant,
3071 ticket->t_unit_res);
3072 trace_xfs_log_ticket_regrant_exit(log, ticket);
3074 ticket->t_curr_res = ticket->t_unit_res;
3075 xlog_tic_reset_res(ticket);
3078 xfs_log_ticket_put(ticket);
3082 * Give back the space left from a reservation.
3084 * All the information we need to make a correct determination of space left
3085 * is present. For non-permanent reservations, things are quite easy. The
3086 * count should have been decremented to zero. We only need to deal with the
3087 * space remaining in the current reservation part of the ticket. If the
3088 * ticket contains a permanent reservation, there may be left over space which
3089 * needs to be released. A count of N means that N-1 refills of the current
3090 * reservation can be done before we need to ask for more space. The first
3091 * one goes to fill up the first current reservation. Once we run out of
3092 * space, the count will stay at zero and the only space remaining will be
3093 * in the current reservation field.
3096 xfs_log_ticket_ungrant(
3098 struct xlog_ticket *ticket)
3102 trace_xfs_log_ticket_ungrant(log, ticket);
3104 if (ticket->t_cnt > 0)
3107 trace_xfs_log_ticket_ungrant_sub(log, ticket);
3110 * If this is a permanent reservation ticket, we may be able to free
3111 * up more space based on the remaining count.
3113 bytes = ticket->t_curr_res;
3114 if (ticket->t_cnt > 0) {
3115 ASSERT(ticket->t_flags & XLOG_TIC_PERM_RESERV);
3116 bytes += ticket->t_unit_res*ticket->t_cnt;
3119 xlog_grant_sub_space(log, &log->l_reserve_head.grant, bytes);
3120 xlog_grant_sub_space(log, &log->l_write_head.grant, bytes);
3122 trace_xfs_log_ticket_ungrant_exit(log, ticket);
3124 xfs_log_space_wake(log->l_mp);
3125 xfs_log_ticket_put(ticket);
3129 * This routine will mark the current iclog in the ring as WANT_SYNC and move
3130 * the current iclog pointer to the next iclog in the ring.
3133 xlog_state_switch_iclogs(
3135 struct xlog_in_core *iclog,
3138 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);
3139 assert_spin_locked(&log->l_icloglock);
3142 eventual_size = iclog->ic_offset;
3143 iclog->ic_state = XLOG_STATE_WANT_SYNC;
3144 iclog->ic_header.h_prev_block = cpu_to_be32(log->l_prev_block);
3145 log->l_prev_block = log->l_curr_block;
3146 log->l_prev_cycle = log->l_curr_cycle;
3148 /* roll log?: ic_offset changed later */
3149 log->l_curr_block += BTOBB(eventual_size)+BTOBB(log->l_iclog_hsize);
3151 /* Round up to next log-sunit */
3152 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb) &&
3153 log->l_mp->m_sb.sb_logsunit > 1) {
3154 uint32_t sunit_bb = BTOBB(log->l_mp->m_sb.sb_logsunit);
3155 log->l_curr_block = roundup(log->l_curr_block, sunit_bb);
3158 if (log->l_curr_block >= log->l_logBBsize) {
3160 * Rewind the current block before the cycle is bumped to make
3161 * sure that the combined LSN never transiently moves forward
3162 * when the log wraps to the next cycle. This is to support the
3163 * unlocked sample of these fields from xlog_valid_lsn(). Most
3164 * other cases should acquire l_icloglock.
3166 log->l_curr_block -= log->l_logBBsize;
3167 ASSERT(log->l_curr_block >= 0);
3169 log->l_curr_cycle++;
3170 if (log->l_curr_cycle == XLOG_HEADER_MAGIC_NUM)
3171 log->l_curr_cycle++;
3173 ASSERT(iclog == log->l_iclog);
3174 log->l_iclog = iclog->ic_next;
3178 * Write out all data in the in-core log as of this exact moment in time.
3180 * Data may be written to the in-core log during this call. However,
3181 * we don't guarantee this data will be written out. A change from past
3182 * implementation means this routine will *not* write out zero length LRs.
3184 * Basically, we try and perform an intelligent scan of the in-core logs.
3185 * If we determine there is no flushable data, we just return. There is no
3186 * flushable data if:
3188 * 1. the current iclog is active and has no data; the previous iclog
3189 * is in the active or dirty state.
3190 * 2. the current iclog is drity, and the previous iclog is in the
3191 * active or dirty state.
3195 * 1. the current iclog is not in the active nor dirty state.
3196 * 2. the current iclog dirty, and the previous iclog is not in the
3197 * active nor dirty state.
3198 * 3. the current iclog is active, and there is another thread writing
3199 * to this particular iclog.
3200 * 4. a) the current iclog is active and has no other writers
3201 * b) when we return from flushing out this iclog, it is still
3202 * not in the active nor dirty state.
3206 struct xfs_mount *mp,
3209 struct xlog *log = mp->m_log;
3210 struct xlog_in_core *iclog;
3213 XFS_STATS_INC(mp, xs_log_force);
3214 trace_xfs_log_force(mp, 0, _RET_IP_);
3216 xlog_cil_force(log);
3218 spin_lock(&log->l_icloglock);
3219 iclog = log->l_iclog;
3220 if (iclog->ic_state == XLOG_STATE_IOERROR)
3223 if (iclog->ic_state == XLOG_STATE_DIRTY ||
3224 (iclog->ic_state == XLOG_STATE_ACTIVE &&
3225 atomic_read(&iclog->ic_refcnt) == 0 && iclog->ic_offset == 0)) {
3227 * If the head is dirty or (active and empty), then we need to
3228 * look at the previous iclog.
3230 * If the previous iclog is active or dirty we are done. There
3231 * is nothing to sync out. Otherwise, we attach ourselves to the
3232 * previous iclog and go to sleep.
3234 iclog = iclog->ic_prev;
3235 } else if (iclog->ic_state == XLOG_STATE_ACTIVE) {
3236 if (atomic_read(&iclog->ic_refcnt) == 0) {
3238 * We are the only one with access to this iclog.
3240 * Flush it out now. There should be a roundoff of zero
3241 * to show that someone has already taken care of the
3242 * roundoff from the previous sync.
3244 atomic_inc(&iclog->ic_refcnt);
3245 lsn = be64_to_cpu(iclog->ic_header.h_lsn);
3246 xlog_state_switch_iclogs(log, iclog, 0);
3247 if (xlog_state_release_iclog(log, iclog))
3250 if (be64_to_cpu(iclog->ic_header.h_lsn) != lsn)
3254 * Someone else is writing to this iclog.
3256 * Use its call to flush out the data. However, the
3257 * other thread may not force out this LR, so we mark
3260 xlog_state_switch_iclogs(log, iclog, 0);
3264 * If the head iclog is not active nor dirty, we just attach
3265 * ourselves to the head and go to sleep if necessary.
3270 if (flags & XFS_LOG_SYNC)
3271 return xlog_wait_on_iclog(iclog);
3273 spin_unlock(&log->l_icloglock);
3276 spin_unlock(&log->l_icloglock);
3281 __xfs_log_force_lsn(
3282 struct xfs_mount *mp,
3288 struct xlog *log = mp->m_log;
3289 struct xlog_in_core *iclog;
3291 spin_lock(&log->l_icloglock);
3292 iclog = log->l_iclog;
3293 if (iclog->ic_state == XLOG_STATE_IOERROR)
3296 while (be64_to_cpu(iclog->ic_header.h_lsn) != lsn) {
3297 iclog = iclog->ic_next;
3298 if (iclog == log->l_iclog)
3302 if (iclog->ic_state == XLOG_STATE_ACTIVE) {
3304 * We sleep here if we haven't already slept (e.g. this is the
3305 * first time we've looked at the correct iclog buf) and the
3306 * buffer before us is going to be sync'ed. The reason for this
3307 * is that if we are doing sync transactions here, by waiting
3308 * for the previous I/O to complete, we can allow a few more
3309 * transactions into this iclog before we close it down.
3311 * Otherwise, we mark the buffer WANT_SYNC, and bump up the
3312 * refcnt so we can release the log (which drops the ref count).
3313 * The state switch keeps new transaction commits from using
3314 * this buffer. When the current commits finish writing into
3315 * the buffer, the refcount will drop to zero and the buffer
3318 if (!already_slept &&
3319 (iclog->ic_prev->ic_state == XLOG_STATE_WANT_SYNC ||
3320 iclog->ic_prev->ic_state == XLOG_STATE_SYNCING)) {
3321 XFS_STATS_INC(mp, xs_log_force_sleep);
3323 xlog_wait(&iclog->ic_prev->ic_write_wait,
3327 atomic_inc(&iclog->ic_refcnt);
3328 xlog_state_switch_iclogs(log, iclog, 0);
3329 if (xlog_state_release_iclog(log, iclog))
3335 if (flags & XFS_LOG_SYNC)
3336 return xlog_wait_on_iclog(iclog);
3338 spin_unlock(&log->l_icloglock);
3341 spin_unlock(&log->l_icloglock);
3346 * Force the in-core log to disk for a specific LSN.
3348 * Find in-core log with lsn.
3349 * If it is in the DIRTY state, just return.
3350 * If it is in the ACTIVE state, move the in-core log into the WANT_SYNC
3351 * state and go to sleep or return.
3352 * If it is in any other state, go to sleep or return.
3354 * Synchronous forces are implemented with a wait queue. All callers trying
3355 * to force a given lsn to disk must wait on the queue attached to the
3356 * specific in-core log. When given in-core log finally completes its write
3357 * to disk, that thread will wake up all threads waiting on the queue.
3361 struct xfs_mount *mp,
3369 XFS_STATS_INC(mp, xs_log_force);
3370 trace_xfs_log_force(mp, lsn, _RET_IP_);
3372 lsn = xlog_cil_force_lsn(mp->m_log, lsn);
3373 if (lsn == NULLCOMMITLSN)
3376 ret = __xfs_log_force_lsn(mp, lsn, flags, log_flushed, false);
3378 ret = __xfs_log_force_lsn(mp, lsn, flags, log_flushed, true);
3383 * Free a used ticket when its refcount falls to zero.
3387 xlog_ticket_t *ticket)
3389 ASSERT(atomic_read(&ticket->t_ref) > 0);
3390 if (atomic_dec_and_test(&ticket->t_ref))
3391 kmem_cache_free(xfs_log_ticket_zone, ticket);
3396 xlog_ticket_t *ticket)
3398 ASSERT(atomic_read(&ticket->t_ref) > 0);
3399 atomic_inc(&ticket->t_ref);
3404 * Figure out the total log space unit (in bytes) that would be
3405 * required for a log ticket.
3408 xfs_log_calc_unit_res(
3409 struct xfs_mount *mp,
3412 struct xlog *log = mp->m_log;
3417 * Permanent reservations have up to 'cnt'-1 active log operations
3418 * in the log. A unit in this case is the amount of space for one
3419 * of these log operations. Normal reservations have a cnt of 1
3420 * and their unit amount is the total amount of space required.
3422 * The following lines of code account for non-transaction data
3423 * which occupy space in the on-disk log.
3425 * Normal form of a transaction is:
3426 * <oph><trans-hdr><start-oph><reg1-oph><reg1><reg2-oph>...<commit-oph>
3427 * and then there are LR hdrs, split-recs and roundoff at end of syncs.
3429 * We need to account for all the leadup data and trailer data
3430 * around the transaction data.
3431 * And then we need to account for the worst case in terms of using
3433 * The worst case will happen if:
3434 * - the placement of the transaction happens to be such that the
3435 * roundoff is at its maximum
3436 * - the transaction data is synced before the commit record is synced
3437 * i.e. <transaction-data><roundoff> | <commit-rec><roundoff>
3438 * Therefore the commit record is in its own Log Record.
3439 * This can happen as the commit record is called with its
3440 * own region to xlog_write().
3441 * This then means that in the worst case, roundoff can happen for
3442 * the commit-rec as well.
3443 * The commit-rec is smaller than padding in this scenario and so it is
3444 * not added separately.
3447 /* for trans header */
3448 unit_bytes += sizeof(xlog_op_header_t);
3449 unit_bytes += sizeof(xfs_trans_header_t);
3452 unit_bytes += sizeof(xlog_op_header_t);
3455 * for LR headers - the space for data in an iclog is the size minus
3456 * the space used for the headers. If we use the iclog size, then we
3457 * undercalculate the number of headers required.
3459 * Furthermore - the addition of op headers for split-recs might
3460 * increase the space required enough to require more log and op
3461 * headers, so take that into account too.
3463 * IMPORTANT: This reservation makes the assumption that if this
3464 * transaction is the first in an iclog and hence has the LR headers
3465 * accounted to it, then the remaining space in the iclog is
3466 * exclusively for this transaction. i.e. if the transaction is larger
3467 * than the iclog, it will be the only thing in that iclog.
3468 * Fundamentally, this means we must pass the entire log vector to
3469 * xlog_write to guarantee this.
3471 iclog_space = log->l_iclog_size - log->l_iclog_hsize;
3472 num_headers = howmany(unit_bytes, iclog_space);
3474 /* for split-recs - ophdrs added when data split over LRs */
3475 unit_bytes += sizeof(xlog_op_header_t) * num_headers;
3477 /* add extra header reservations if we overrun */
3478 while (!num_headers ||
3479 howmany(unit_bytes, iclog_space) > num_headers) {
3480 unit_bytes += sizeof(xlog_op_header_t);
3483 unit_bytes += log->l_iclog_hsize * num_headers;
3485 /* for commit-rec LR header - note: padding will subsume the ophdr */
3486 unit_bytes += log->l_iclog_hsize;
3488 /* for roundoff padding for transaction data and one for commit record */
3489 if (xfs_sb_version_haslogv2(&mp->m_sb) && mp->m_sb.sb_logsunit > 1) {
3490 /* log su roundoff */
3491 unit_bytes += 2 * mp->m_sb.sb_logsunit;
3494 unit_bytes += 2 * BBSIZE;
3501 * Allocate and initialise a new log ticket.
3503 struct xlog_ticket *
3511 struct xlog_ticket *tic;
3514 tic = kmem_cache_zalloc(xfs_log_ticket_zone, GFP_NOFS | __GFP_NOFAIL);
3516 unit_res = xfs_log_calc_unit_res(log->l_mp, unit_bytes);
3518 atomic_set(&tic->t_ref, 1);
3519 tic->t_task = current;
3520 INIT_LIST_HEAD(&tic->t_queue);
3521 tic->t_unit_res = unit_res;
3522 tic->t_curr_res = unit_res;
3525 tic->t_tid = prandom_u32();
3526 tic->t_clientid = client;
3528 tic->t_flags |= XLOG_TIC_PERM_RESERV;
3530 xlog_tic_reset_res(tic);
3537 * Make sure that the destination ptr is within the valid data region of
3538 * one of the iclogs. This uses backup pointers stored in a different
3539 * part of the log in case we trash the log structure.
3542 xlog_verify_dest_ptr(
3549 for (i = 0; i < log->l_iclog_bufs; i++) {
3550 if (ptr >= log->l_iclog_bak[i] &&
3551 ptr <= log->l_iclog_bak[i] + log->l_iclog_size)
3556 xfs_emerg(log->l_mp, "%s: invalid ptr", __func__);
3560 * Check to make sure the grant write head didn't just over lap the tail. If
3561 * the cycles are the same, we can't be overlapping. Otherwise, make sure that
3562 * the cycles differ by exactly one and check the byte count.
3564 * This check is run unlocked, so can give false positives. Rather than assert
3565 * on failures, use a warn-once flag and a panic tag to allow the admin to
3566 * determine if they want to panic the machine when such an error occurs. For
3567 * debug kernels this will have the same effect as using an assert but, unlinke
3568 * an assert, it can be turned off at runtime.
3571 xlog_verify_grant_tail(
3574 int tail_cycle, tail_blocks;
3577 xlog_crack_grant_head(&log->l_write_head.grant, &cycle, &space);
3578 xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_blocks);
3579 if (tail_cycle != cycle) {
3580 if (cycle - 1 != tail_cycle &&
3581 !(log->l_flags & XLOG_TAIL_WARN)) {
3582 xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES,
3583 "%s: cycle - 1 != tail_cycle", __func__);
3584 log->l_flags |= XLOG_TAIL_WARN;
3587 if (space > BBTOB(tail_blocks) &&
3588 !(log->l_flags & XLOG_TAIL_WARN)) {
3589 xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES,
3590 "%s: space > BBTOB(tail_blocks)", __func__);
3591 log->l_flags |= XLOG_TAIL_WARN;
3596 /* check if it will fit */
3598 xlog_verify_tail_lsn(
3600 struct xlog_in_core *iclog,
3605 if (CYCLE_LSN(tail_lsn) == log->l_prev_cycle) {
3607 log->l_logBBsize - (log->l_prev_block - BLOCK_LSN(tail_lsn));
3608 if (blocks < BTOBB(iclog->ic_offset)+BTOBB(log->l_iclog_hsize))
3609 xfs_emerg(log->l_mp, "%s: ran out of log space", __func__);
3611 ASSERT(CYCLE_LSN(tail_lsn)+1 == log->l_prev_cycle);
3613 if (BLOCK_LSN(tail_lsn) == log->l_prev_block)
3614 xfs_emerg(log->l_mp, "%s: tail wrapped", __func__);
3616 blocks = BLOCK_LSN(tail_lsn) - log->l_prev_block;
3617 if (blocks < BTOBB(iclog->ic_offset) + 1)
3618 xfs_emerg(log->l_mp, "%s: ran out of log space", __func__);
3623 * Perform a number of checks on the iclog before writing to disk.
3625 * 1. Make sure the iclogs are still circular
3626 * 2. Make sure we have a good magic number
3627 * 3. Make sure we don't have magic numbers in the data
3628 * 4. Check fields of each log operation header for:
3629 * A. Valid client identifier
3630 * B. tid ptr value falls in valid ptr space (user space code)
3631 * C. Length in log record header is correct according to the
3632 * individual operation headers within record.
3633 * 5. When a bwrite will occur within 5 blocks of the front of the physical
3634 * log, check the preceding blocks of the physical log to make sure all
3635 * the cycle numbers agree with the current cycle number.
3640 struct xlog_in_core *iclog,
3643 xlog_op_header_t *ophead;
3644 xlog_in_core_t *icptr;
3645 xlog_in_core_2_t *xhdr;
3646 void *base_ptr, *ptr, *p;
3647 ptrdiff_t field_offset;
3649 int len, i, j, k, op_len;
3652 /* check validity of iclog pointers */
3653 spin_lock(&log->l_icloglock);
3654 icptr = log->l_iclog;
3655 for (i = 0; i < log->l_iclog_bufs; i++, icptr = icptr->ic_next)
3658 if (icptr != log->l_iclog)
3659 xfs_emerg(log->l_mp, "%s: corrupt iclog ring", __func__);
3660 spin_unlock(&log->l_icloglock);
3662 /* check log magic numbers */
3663 if (iclog->ic_header.h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
3664 xfs_emerg(log->l_mp, "%s: invalid magic num", __func__);
3666 base_ptr = ptr = &iclog->ic_header;
3667 p = &iclog->ic_header;
3668 for (ptr += BBSIZE; ptr < base_ptr + count; ptr += BBSIZE) {
3669 if (*(__be32 *)ptr == cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
3670 xfs_emerg(log->l_mp, "%s: unexpected magic num",
3675 len = be32_to_cpu(iclog->ic_header.h_num_logops);
3676 base_ptr = ptr = iclog->ic_datap;
3678 xhdr = iclog->ic_data;
3679 for (i = 0; i < len; i++) {
3682 /* clientid is only 1 byte */
3683 p = &ophead->oh_clientid;
3684 field_offset = p - base_ptr;
3685 if (field_offset & 0x1ff) {
3686 clientid = ophead->oh_clientid;
3688 idx = BTOBBT((char *)&ophead->oh_clientid - iclog->ic_datap);
3689 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) {
3690 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3691 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3692 clientid = xlog_get_client_id(
3693 xhdr[j].hic_xheader.xh_cycle_data[k]);
3695 clientid = xlog_get_client_id(
3696 iclog->ic_header.h_cycle_data[idx]);
3699 if (clientid != XFS_TRANSACTION && clientid != XFS_LOG)
3701 "%s: invalid clientid %d op "PTR_FMT" offset 0x%lx",
3702 __func__, clientid, ophead,
3703 (unsigned long)field_offset);
3706 p = &ophead->oh_len;
3707 field_offset = p - base_ptr;
3708 if (field_offset & 0x1ff) {
3709 op_len = be32_to_cpu(ophead->oh_len);
3711 idx = BTOBBT((uintptr_t)&ophead->oh_len -
3712 (uintptr_t)iclog->ic_datap);
3713 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) {
3714 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3715 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3716 op_len = be32_to_cpu(xhdr[j].hic_xheader.xh_cycle_data[k]);
3718 op_len = be32_to_cpu(iclog->ic_header.h_cycle_data[idx]);
3721 ptr += sizeof(xlog_op_header_t) + op_len;
3727 * Mark all iclogs IOERROR. l_icloglock is held by the caller.
3733 xlog_in_core_t *iclog, *ic;
3735 iclog = log->l_iclog;
3736 if (iclog->ic_state != XLOG_STATE_IOERROR) {
3738 * Mark all the incore logs IOERROR.
3739 * From now on, no log flushes will result.
3743 ic->ic_state = XLOG_STATE_IOERROR;
3745 } while (ic != iclog);
3749 * Return non-zero, if state transition has already happened.
3755 * This is called from xfs_force_shutdown, when we're forcibly
3756 * shutting down the filesystem, typically because of an IO error.
3757 * Our main objectives here are to make sure that:
3758 * a. if !logerror, flush the logs to disk. Anything modified
3759 * after this is ignored.
3760 * b. the filesystem gets marked 'SHUTDOWN' for all interested
3761 * parties to find out, 'atomically'.
3762 * c. those who're sleeping on log reservations, pinned objects and
3763 * other resources get woken up, and be told the bad news.
3764 * d. nothing new gets queued up after (b) and (c) are done.
3766 * Note: for the !logerror case we need to flush the regions held in memory out
3767 * to disk first. This needs to be done before the log is marked as shutdown,
3768 * otherwise the iclog writes will fail.
3771 xfs_log_force_umount(
3772 struct xfs_mount *mp,
3781 * If this happens during log recovery, don't worry about
3782 * locking; the log isn't open for business yet.
3785 log->l_flags & XLOG_ACTIVE_RECOVERY) {
3786 mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN;
3788 mp->m_sb_bp->b_flags |= XBF_DONE;
3793 * Somebody could've already done the hard work for us.
3794 * No need to get locks for this.
3796 if (logerror && log->l_iclog->ic_state == XLOG_STATE_IOERROR) {
3797 ASSERT(XLOG_FORCED_SHUTDOWN(log));
3802 * Flush all the completed transactions to disk before marking the log
3803 * being shut down. We need to do it in this order to ensure that
3804 * completed operations are safely on disk before we shut down, and that
3805 * we don't have to issue any buffer IO after the shutdown flags are set
3806 * to guarantee this.
3809 xfs_log_force(mp, XFS_LOG_SYNC);
3812 * mark the filesystem and the as in a shutdown state and wake
3813 * everybody up to tell them the bad news.
3815 spin_lock(&log->l_icloglock);
3816 mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN;
3818 mp->m_sb_bp->b_flags |= XBF_DONE;
3821 * Mark the log and the iclogs with IO error flags to prevent any
3822 * further log IO from being issued or completed.
3824 log->l_flags |= XLOG_IO_ERROR;
3825 retval = xlog_state_ioerror(log);
3826 spin_unlock(&log->l_icloglock);
3829 * We don't want anybody waiting for log reservations after this. That
3830 * means we have to wake up everybody queued up on reserveq as well as
3831 * writeq. In addition, we make sure in xlog_{re}grant_log_space that
3832 * we don't enqueue anything once the SHUTDOWN flag is set, and this
3833 * action is protected by the grant locks.
3835 xlog_grant_head_wake_all(&log->l_reserve_head);
3836 xlog_grant_head_wake_all(&log->l_write_head);
3839 * Wake up everybody waiting on xfs_log_force. Wake the CIL push first
3840 * as if the log writes were completed. The abort handling in the log
3841 * item committed callback functions will do this again under lock to
3844 spin_lock(&log->l_cilp->xc_push_lock);
3845 wake_up_all(&log->l_cilp->xc_commit_wait);
3846 spin_unlock(&log->l_cilp->xc_push_lock);
3847 xlog_state_do_callback(log);
3849 /* return non-zero if log IOERROR transition had already happened */
3857 xlog_in_core_t *iclog;
3859 iclog = log->l_iclog;
3861 /* endianness does not matter here, zero is zero in
3864 if (iclog->ic_header.h_num_logops)
3866 iclog = iclog->ic_next;
3867 } while (iclog != log->l_iclog);
3872 * Verify that an LSN stamped into a piece of metadata is valid. This is
3873 * intended for use in read verifiers on v5 superblocks.
3877 struct xfs_mount *mp,
3880 struct xlog *log = mp->m_log;
3884 * norecovery mode skips mount-time log processing and unconditionally
3885 * resets the in-core LSN. We can't validate in this mode, but
3886 * modifications are not allowed anyways so just return true.
3888 if (mp->m_flags & XFS_MOUNT_NORECOVERY)
3892 * Some metadata LSNs are initialized to NULL (e.g., the agfl). This is
3893 * handled by recovery and thus safe to ignore here.
3895 if (lsn == NULLCOMMITLSN)
3898 valid = xlog_valid_lsn(mp->m_log, lsn);
3900 /* warn the user about what's gone wrong before verifier failure */
3902 spin_lock(&log->l_icloglock);
3904 "Corruption warning: Metadata has LSN (%d:%d) ahead of current LSN (%d:%d). "
3905 "Please unmount and run xfs_repair (>= v4.3) to resolve.",
3906 CYCLE_LSN(lsn), BLOCK_LSN(lsn),
3907 log->l_curr_cycle, log->l_curr_block);
3908 spin_unlock(&log->l_icloglock);
3915 xfs_log_in_recovery(
3916 struct xfs_mount *mp)
3918 struct xlog *log = mp->m_log;
3920 return log->l_flags & XLOG_ACTIVE_RECOVERY;