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- // SPDX-License-Identifier: GPL-2.0
- /*
- * Copyright (c) 2000-2005 Silicon Graphics, Inc.
- * All Rights Reserved.
- */
- #include "xfs.h"
- #include "xfs_fs.h"
- #include "xfs_shared.h"
- #include "xfs_format.h"
- #include "xfs_log_format.h"
- #include "xfs_trans_resv.h"
- #include "xfs_mount.h"
- #include "xfs_errortag.h"
- #include "xfs_error.h"
- #include "xfs_trans.h"
- #include "xfs_trans_priv.h"
- #include "xfs_log.h"
- #include "xfs_log_priv.h"
- #include "xfs_trace.h"
- #include "xfs_sysfs.h"
- #include "xfs_sb.h"
- #include "xfs_health.h"
- kmem_zone_t *xfs_log_ticket_zone;
- /* Local miscellaneous function prototypes */
- STATIC struct xlog *
- xlog_alloc_log(
- struct xfs_mount *mp,
- struct xfs_buftarg *log_target,
- xfs_daddr_t blk_offset,
- int num_bblks);
- STATIC int
- xlog_space_left(
- struct xlog *log,
- atomic64_t *head);
- STATIC void
- xlog_dealloc_log(
- struct xlog *log);
- /* local state machine functions */
- STATIC void xlog_state_done_syncing(
- struct xlog_in_core *iclog);
- STATIC int
- xlog_state_get_iclog_space(
- struct xlog *log,
- int len,
- struct xlog_in_core **iclog,
- struct xlog_ticket *ticket,
- int *continued_write,
- int *logoffsetp);
- STATIC void
- xlog_state_switch_iclogs(
- struct xlog *log,
- struct xlog_in_core *iclog,
- int eventual_size);
- STATIC void
- xlog_grant_push_ail(
- struct xlog *log,
- int need_bytes);
- STATIC void
- xlog_sync(
- struct xlog *log,
- struct xlog_in_core *iclog);
- #if defined(DEBUG)
- STATIC void
- xlog_verify_dest_ptr(
- struct xlog *log,
- void *ptr);
- STATIC void
- xlog_verify_grant_tail(
- struct xlog *log);
- STATIC void
- xlog_verify_iclog(
- struct xlog *log,
- struct xlog_in_core *iclog,
- int count);
- STATIC void
- xlog_verify_tail_lsn(
- struct xlog *log,
- struct xlog_in_core *iclog,
- xfs_lsn_t tail_lsn);
- #else
- #define xlog_verify_dest_ptr(a,b)
- #define xlog_verify_grant_tail(a)
- #define xlog_verify_iclog(a,b,c)
- #define xlog_verify_tail_lsn(a,b,c)
- #endif
- STATIC int
- xlog_iclogs_empty(
- struct xlog *log);
- static void
- xlog_grant_sub_space(
- struct xlog *log,
- atomic64_t *head,
- int bytes)
- {
- int64_t head_val = atomic64_read(head);
- int64_t new, old;
- do {
- int cycle, space;
- xlog_crack_grant_head_val(head_val, &cycle, &space);
- space -= bytes;
- if (space < 0) {
- space += log->l_logsize;
- cycle--;
- }
- old = head_val;
- new = xlog_assign_grant_head_val(cycle, space);
- head_val = atomic64_cmpxchg(head, old, new);
- } while (head_val != old);
- }
- static void
- xlog_grant_add_space(
- struct xlog *log,
- atomic64_t *head,
- int bytes)
- {
- int64_t head_val = atomic64_read(head);
- int64_t new, old;
- do {
- int tmp;
- int cycle, space;
- xlog_crack_grant_head_val(head_val, &cycle, &space);
- tmp = log->l_logsize - space;
- if (tmp > bytes)
- space += bytes;
- else {
- space = bytes - tmp;
- cycle++;
- }
- old = head_val;
- new = xlog_assign_grant_head_val(cycle, space);
- head_val = atomic64_cmpxchg(head, old, new);
- } while (head_val != old);
- }
- STATIC void
- xlog_grant_head_init(
- struct xlog_grant_head *head)
- {
- xlog_assign_grant_head(&head->grant, 1, 0);
- INIT_LIST_HEAD(&head->waiters);
- spin_lock_init(&head->lock);
- }
- STATIC void
- xlog_grant_head_wake_all(
- struct xlog_grant_head *head)
- {
- struct xlog_ticket *tic;
- spin_lock(&head->lock);
- list_for_each_entry(tic, &head->waiters, t_queue)
- wake_up_process(tic->t_task);
- spin_unlock(&head->lock);
- }
- static inline int
- xlog_ticket_reservation(
- struct xlog *log,
- struct xlog_grant_head *head,
- struct xlog_ticket *tic)
- {
- if (head == &log->l_write_head) {
- ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV);
- return tic->t_unit_res;
- } else {
- if (tic->t_flags & XLOG_TIC_PERM_RESERV)
- return tic->t_unit_res * tic->t_cnt;
- else
- return tic->t_unit_res;
- }
- }
- STATIC bool
- xlog_grant_head_wake(
- struct xlog *log,
- struct xlog_grant_head *head,
- int *free_bytes)
- {
- struct xlog_ticket *tic;
- int need_bytes;
- bool woken_task = false;
- list_for_each_entry(tic, &head->waiters, t_queue) {
- /*
- * There is a chance that the size of the CIL checkpoints in
- * progress at the last AIL push target calculation resulted in
- * limiting the target to the log head (l_last_sync_lsn) at the
- * time. This may not reflect where the log head is now as the
- * CIL checkpoints may have completed.
- *
- * Hence when we are woken here, it may be that the head of the
- * log that has moved rather than the tail. As the tail didn't
- * move, there still won't be space available for the
- * reservation we require. However, if the AIL has already
- * pushed to the target defined by the old log head location, we
- * will hang here waiting for something else to update the AIL
- * push target.
- *
- * Therefore, if there isn't space to wake the first waiter on
- * the grant head, we need to push the AIL again to ensure the
- * target reflects both the current log tail and log head
- * position before we wait for the tail to move again.
- */
- need_bytes = xlog_ticket_reservation(log, head, tic);
- if (*free_bytes < need_bytes) {
- if (!woken_task)
- xlog_grant_push_ail(log, need_bytes);
- return false;
- }
- *free_bytes -= need_bytes;
- trace_xfs_log_grant_wake_up(log, tic);
- wake_up_process(tic->t_task);
- woken_task = true;
- }
- return true;
- }
- STATIC int
- xlog_grant_head_wait(
- struct xlog *log,
- struct xlog_grant_head *head,
- struct xlog_ticket *tic,
- int need_bytes) __releases(&head->lock)
- __acquires(&head->lock)
- {
- list_add_tail(&tic->t_queue, &head->waiters);
- do {
- if (XLOG_FORCED_SHUTDOWN(log))
- goto shutdown;
- xlog_grant_push_ail(log, need_bytes);
- __set_current_state(TASK_UNINTERRUPTIBLE);
- spin_unlock(&head->lock);
- XFS_STATS_INC(log->l_mp, xs_sleep_logspace);
- trace_xfs_log_grant_sleep(log, tic);
- schedule();
- trace_xfs_log_grant_wake(log, tic);
- spin_lock(&head->lock);
- if (XLOG_FORCED_SHUTDOWN(log))
- goto shutdown;
- } while (xlog_space_left(log, &head->grant) < need_bytes);
- list_del_init(&tic->t_queue);
- return 0;
- shutdown:
- list_del_init(&tic->t_queue);
- return -EIO;
- }
- /*
- * Atomically get the log space required for a log ticket.
- *
- * Once a ticket gets put onto head->waiters, it will only return after the
- * needed reservation is satisfied.
- *
- * This function is structured so that it has a lock free fast path. This is
- * necessary because every new transaction reservation will come through this
- * path. Hence any lock will be globally hot if we take it unconditionally on
- * every pass.
- *
- * As tickets are only ever moved on and off head->waiters under head->lock, we
- * only need to take that lock if we are going to add the ticket to the queue
- * and sleep. We can avoid taking the lock if the ticket was never added to
- * head->waiters because the t_queue list head will be empty and we hold the
- * only reference to it so it can safely be checked unlocked.
- */
- STATIC int
- xlog_grant_head_check(
- struct xlog *log,
- struct xlog_grant_head *head,
- struct xlog_ticket *tic,
- int *need_bytes)
- {
- int free_bytes;
- int error = 0;
- ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY));
- /*
- * If there are other waiters on the queue then give them a chance at
- * logspace before us. Wake up the first waiters, if we do not wake
- * up all the waiters then go to sleep waiting for more free space,
- * otherwise try to get some space for this transaction.
- */
- *need_bytes = xlog_ticket_reservation(log, head, tic);
- free_bytes = xlog_space_left(log, &head->grant);
- if (!list_empty_careful(&head->waiters)) {
- spin_lock(&head->lock);
- if (!xlog_grant_head_wake(log, head, &free_bytes) ||
- free_bytes < *need_bytes) {
- error = xlog_grant_head_wait(log, head, tic,
- *need_bytes);
- }
- spin_unlock(&head->lock);
- } else if (free_bytes < *need_bytes) {
- spin_lock(&head->lock);
- error = xlog_grant_head_wait(log, head, tic, *need_bytes);
- spin_unlock(&head->lock);
- }
- return error;
- }
- static void
- xlog_tic_reset_res(xlog_ticket_t *tic)
- {
- tic->t_res_num = 0;
- tic->t_res_arr_sum = 0;
- tic->t_res_num_ophdrs = 0;
- }
- static void
- xlog_tic_add_region(xlog_ticket_t *tic, uint len, uint type)
- {
- if (tic->t_res_num == XLOG_TIC_LEN_MAX) {
- /* add to overflow and start again */
- tic->t_res_o_flow += tic->t_res_arr_sum;
- tic->t_res_num = 0;
- tic->t_res_arr_sum = 0;
- }
- tic->t_res_arr[tic->t_res_num].r_len = len;
- tic->t_res_arr[tic->t_res_num].r_type = type;
- tic->t_res_arr_sum += len;
- tic->t_res_num++;
- }
- /*
- * Replenish the byte reservation required by moving the grant write head.
- */
- int
- xfs_log_regrant(
- struct xfs_mount *mp,
- struct xlog_ticket *tic)
- {
- struct xlog *log = mp->m_log;
- int need_bytes;
- int error = 0;
- if (XLOG_FORCED_SHUTDOWN(log))
- return -EIO;
- XFS_STATS_INC(mp, xs_try_logspace);
- /*
- * This is a new transaction on the ticket, so we need to change the
- * transaction ID so that the next transaction has a different TID in
- * the log. Just add one to the existing tid so that we can see chains
- * of rolling transactions in the log easily.
- */
- tic->t_tid++;
- xlog_grant_push_ail(log, tic->t_unit_res);
- tic->t_curr_res = tic->t_unit_res;
- xlog_tic_reset_res(tic);
- if (tic->t_cnt > 0)
- return 0;
- trace_xfs_log_regrant(log, tic);
- error = xlog_grant_head_check(log, &log->l_write_head, tic,
- &need_bytes);
- if (error)
- goto out_error;
- xlog_grant_add_space(log, &log->l_write_head.grant, need_bytes);
- trace_xfs_log_regrant_exit(log, tic);
- xlog_verify_grant_tail(log);
- return 0;
- out_error:
- /*
- * If we are failing, make sure the ticket doesn't have any current
- * reservations. We don't want to add this back when the ticket/
- * transaction gets cancelled.
- */
- tic->t_curr_res = 0;
- tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */
- return error;
- }
- /*
- * Reserve log space and return a ticket corresponding to the reservation.
- *
- * Each reservation is going to reserve extra space for a log record header.
- * When writes happen to the on-disk log, we don't subtract the length of the
- * log record header from any reservation. By wasting space in each
- * reservation, we prevent over allocation problems.
- */
- int
- xfs_log_reserve(
- struct xfs_mount *mp,
- int unit_bytes,
- int cnt,
- struct xlog_ticket **ticp,
- uint8_t client,
- bool permanent)
- {
- struct xlog *log = mp->m_log;
- struct xlog_ticket *tic;
- int need_bytes;
- int error = 0;
- ASSERT(client == XFS_TRANSACTION || client == XFS_LOG);
- if (XLOG_FORCED_SHUTDOWN(log))
- return -EIO;
- XFS_STATS_INC(mp, xs_try_logspace);
- ASSERT(*ticp == NULL);
- tic = xlog_ticket_alloc(log, unit_bytes, cnt, client, permanent);
- *ticp = tic;
- xlog_grant_push_ail(log, tic->t_cnt ? tic->t_unit_res * tic->t_cnt
- : tic->t_unit_res);
- trace_xfs_log_reserve(log, tic);
- error = xlog_grant_head_check(log, &log->l_reserve_head, tic,
- &need_bytes);
- if (error)
- goto out_error;
- xlog_grant_add_space(log, &log->l_reserve_head.grant, need_bytes);
- xlog_grant_add_space(log, &log->l_write_head.grant, need_bytes);
- trace_xfs_log_reserve_exit(log, tic);
- xlog_verify_grant_tail(log);
- return 0;
- out_error:
- /*
- * If we are failing, make sure the ticket doesn't have any current
- * reservations. We don't want to add this back when the ticket/
- * transaction gets cancelled.
- */
- tic->t_curr_res = 0;
- tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */
- return error;
- }
- static bool
- __xlog_state_release_iclog(
- struct xlog *log,
- struct xlog_in_core *iclog)
- {
- lockdep_assert_held(&log->l_icloglock);
- if (iclog->ic_state == XLOG_STATE_WANT_SYNC) {
- /* update tail before writing to iclog */
- xfs_lsn_t tail_lsn = xlog_assign_tail_lsn(log->l_mp);
- iclog->ic_state = XLOG_STATE_SYNCING;
- iclog->ic_header.h_tail_lsn = cpu_to_be64(tail_lsn);
- xlog_verify_tail_lsn(log, iclog, tail_lsn);
- /* cycle incremented when incrementing curr_block */
- return true;
- }
- ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);
- return false;
- }
- /*
- * Flush iclog to disk if this is the last reference to the given iclog and the
- * it is in the WANT_SYNC state.
- */
- static int
- xlog_state_release_iclog(
- struct xlog *log,
- struct xlog_in_core *iclog)
- {
- lockdep_assert_held(&log->l_icloglock);
- if (iclog->ic_state == XLOG_STATE_IOERROR)
- return -EIO;
- if (atomic_dec_and_test(&iclog->ic_refcnt) &&
- __xlog_state_release_iclog(log, iclog)) {
- spin_unlock(&log->l_icloglock);
- xlog_sync(log, iclog);
- spin_lock(&log->l_icloglock);
- }
- return 0;
- }
- void
- xfs_log_release_iclog(
- struct xlog_in_core *iclog)
- {
- struct xlog *log = iclog->ic_log;
- bool sync = false;
- if (atomic_dec_and_lock(&iclog->ic_refcnt, &log->l_icloglock)) {
- if (iclog->ic_state != XLOG_STATE_IOERROR)
- sync = __xlog_state_release_iclog(log, iclog);
- spin_unlock(&log->l_icloglock);
- }
- if (sync)
- xlog_sync(log, iclog);
- }
- /*
- * Mount a log filesystem
- *
- * mp - ubiquitous xfs mount point structure
- * log_target - buftarg of on-disk log device
- * blk_offset - Start block # where block size is 512 bytes (BBSIZE)
- * num_bblocks - Number of BBSIZE blocks in on-disk log
- *
- * Return error or zero.
- */
- int
- xfs_log_mount(
- xfs_mount_t *mp,
- xfs_buftarg_t *log_target,
- xfs_daddr_t blk_offset,
- int num_bblks)
- {
- bool fatal = xfs_sb_version_hascrc(&mp->m_sb);
- int error = 0;
- int min_logfsbs;
- if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) {
- xfs_notice(mp, "Mounting V%d Filesystem",
- XFS_SB_VERSION_NUM(&mp->m_sb));
- } else {
- xfs_notice(mp,
- "Mounting V%d filesystem in no-recovery mode. Filesystem will be inconsistent.",
- XFS_SB_VERSION_NUM(&mp->m_sb));
- ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
- }
- mp->m_log = xlog_alloc_log(mp, log_target, blk_offset, num_bblks);
- if (IS_ERR(mp->m_log)) {
- error = PTR_ERR(mp->m_log);
- goto out;
- }
- /*
- * Validate the given log space and drop a critical message via syslog
- * if the log size is too small that would lead to some unexpected
- * situations in transaction log space reservation stage.
- *
- * Note: we can't just reject the mount if the validation fails. This
- * would mean that people would have to downgrade their kernel just to
- * remedy the situation as there is no way to grow the log (short of
- * black magic surgery with xfs_db).
- *
- * We can, however, reject mounts for CRC format filesystems, as the
- * mkfs binary being used to make the filesystem should never create a
- * filesystem with a log that is too small.
- */
- min_logfsbs = xfs_log_calc_minimum_size(mp);
- if (mp->m_sb.sb_logblocks < min_logfsbs) {
- xfs_warn(mp,
- "Log size %d blocks too small, minimum size is %d blocks",
- mp->m_sb.sb_logblocks, min_logfsbs);
- error = -EINVAL;
- } else if (mp->m_sb.sb_logblocks > XFS_MAX_LOG_BLOCKS) {
- xfs_warn(mp,
- "Log size %d blocks too large, maximum size is %lld blocks",
- mp->m_sb.sb_logblocks, XFS_MAX_LOG_BLOCKS);
- error = -EINVAL;
- } else if (XFS_FSB_TO_B(mp, mp->m_sb.sb_logblocks) > XFS_MAX_LOG_BYTES) {
- xfs_warn(mp,
- "log size %lld bytes too large, maximum size is %lld bytes",
- XFS_FSB_TO_B(mp, mp->m_sb.sb_logblocks),
- XFS_MAX_LOG_BYTES);
- error = -EINVAL;
- } else if (mp->m_sb.sb_logsunit > 1 &&
- mp->m_sb.sb_logsunit % mp->m_sb.sb_blocksize) {
- xfs_warn(mp,
- "log stripe unit %u bytes must be a multiple of block size",
- mp->m_sb.sb_logsunit);
- error = -EINVAL;
- fatal = true;
- }
- if (error) {
- /*
- * Log check errors are always fatal on v5; or whenever bad
- * metadata leads to a crash.
- */
- if (fatal) {
- xfs_crit(mp, "AAIEEE! Log failed size checks. Abort!");
- ASSERT(0);
- goto out_free_log;
- }
- xfs_crit(mp, "Log size out of supported range.");
- xfs_crit(mp,
- "Continuing onwards, but if log hangs are experienced then please report this message in the bug report.");
- }
- /*
- * Initialize the AIL now we have a log.
- */
- error = xfs_trans_ail_init(mp);
- if (error) {
- xfs_warn(mp, "AIL initialisation failed: error %d", error);
- goto out_free_log;
- }
- mp->m_log->l_ailp = mp->m_ail;
- /*
- * skip log recovery on a norecovery mount. pretend it all
- * just worked.
- */
- if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) {
- int readonly = (mp->m_flags & XFS_MOUNT_RDONLY);
- if (readonly)
- mp->m_flags &= ~XFS_MOUNT_RDONLY;
- error = xlog_recover(mp->m_log);
- if (readonly)
- mp->m_flags |= XFS_MOUNT_RDONLY;
- if (error) {
- xfs_warn(mp, "log mount/recovery failed: error %d",
- error);
- xlog_recover_cancel(mp->m_log);
- goto out_destroy_ail;
- }
- }
- error = xfs_sysfs_init(&mp->m_log->l_kobj, &xfs_log_ktype, &mp->m_kobj,
- "log");
- if (error)
- goto out_destroy_ail;
- /* Normal transactions can now occur */
- mp->m_log->l_flags &= ~XLOG_ACTIVE_RECOVERY;
- /*
- * Now the log has been fully initialised and we know were our
- * space grant counters are, we can initialise the permanent ticket
- * needed for delayed logging to work.
- */
- xlog_cil_init_post_recovery(mp->m_log);
- return 0;
- out_destroy_ail:
- xfs_trans_ail_destroy(mp);
- out_free_log:
- xlog_dealloc_log(mp->m_log);
- out:
- return error;
- }
- /*
- * Finish the recovery of the file system. This is separate from the
- * xfs_log_mount() call, because it depends on the code in xfs_mountfs() to read
- * in the root and real-time bitmap inodes between calling xfs_log_mount() and
- * here.
- *
- * If we finish recovery successfully, start the background log work. If we are
- * not doing recovery, then we have a RO filesystem and we don't need to start
- * it.
- */
- int
- xfs_log_mount_finish(
- struct xfs_mount *mp)
- {
- int error = 0;
- bool readonly = (mp->m_flags & XFS_MOUNT_RDONLY);
- bool recovered = mp->m_log->l_flags & XLOG_RECOVERY_NEEDED;
- if (mp->m_flags & XFS_MOUNT_NORECOVERY) {
- ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
- return 0;
- } else if (readonly) {
- /* Allow unlinked processing to proceed */
- mp->m_flags &= ~XFS_MOUNT_RDONLY;
- }
- /*
- * During the second phase of log recovery, we need iget and
- * iput to behave like they do for an active filesystem.
- * xfs_fs_drop_inode needs to be able to prevent the deletion
- * of inodes before we're done replaying log items on those
- * inodes. Turn it off immediately after recovery finishes
- * so that we don't leak the quota inodes if subsequent mount
- * activities fail.
- *
- * We let all inodes involved in redo item processing end up on
- * the LRU instead of being evicted immediately so that if we do
- * something to an unlinked inode, the irele won't cause
- * premature truncation and freeing of the inode, which results
- * in log recovery failure. We have to evict the unreferenced
- * lru inodes after clearing SB_ACTIVE because we don't
- * otherwise clean up the lru if there's a subsequent failure in
- * xfs_mountfs, which leads to us leaking the inodes if nothing
- * else (e.g. quotacheck) references the inodes before the
- * mount failure occurs.
- */
- mp->m_super->s_flags |= SB_ACTIVE;
- error = xlog_recover_finish(mp->m_log);
- if (!error)
- xfs_log_work_queue(mp);
- mp->m_super->s_flags &= ~SB_ACTIVE;
- evict_inodes(mp->m_super);
- /*
- * Drain the buffer LRU after log recovery. This is required for v4
- * filesystems to avoid leaving around buffers with NULL verifier ops,
- * but we do it unconditionally to make sure we're always in a clean
- * cache state after mount.
- *
- * Don't push in the error case because the AIL may have pending intents
- * that aren't removed until recovery is cancelled.
- */
- if (!error && recovered) {
- xfs_log_force(mp, XFS_LOG_SYNC);
- xfs_ail_push_all_sync(mp->m_ail);
- }
- xfs_wait_buftarg(mp->m_ddev_targp);
- if (readonly)
- mp->m_flags |= XFS_MOUNT_RDONLY;
- return error;
- }
- /*
- * The mount has failed. Cancel the recovery if it hasn't completed and destroy
- * the log.
- */
- void
- xfs_log_mount_cancel(
- struct xfs_mount *mp)
- {
- xlog_recover_cancel(mp->m_log);
- xfs_log_unmount(mp);
- }
- /*
- * Wait for the iclog to be written disk, or return an error if the log has been
- * shut down.
- */
- static int
- xlog_wait_on_iclog(
- struct xlog_in_core *iclog)
- __releases(iclog->ic_log->l_icloglock)
- {
- struct xlog *log = iclog->ic_log;
- if (!XLOG_FORCED_SHUTDOWN(log) &&
- iclog->ic_state != XLOG_STATE_ACTIVE &&
- iclog->ic_state != XLOG_STATE_DIRTY) {
- XFS_STATS_INC(log->l_mp, xs_log_force_sleep);
- xlog_wait(&iclog->ic_force_wait, &log->l_icloglock);
- } else {
- spin_unlock(&log->l_icloglock);
- }
- if (XLOG_FORCED_SHUTDOWN(log))
- return -EIO;
- return 0;
- }
- /*
- * Write out an unmount record using the ticket provided. We have to account for
- * the data space used in the unmount ticket as this write is not done from a
- * transaction context that has already done the accounting for us.
- */
- static int
- xlog_write_unmount_record(
- struct xlog *log,
- struct xlog_ticket *ticket,
- xfs_lsn_t *lsn,
- uint flags)
- {
- struct xfs_unmount_log_format ulf = {
- .magic = XLOG_UNMOUNT_TYPE,
- };
- struct xfs_log_iovec reg = {
- .i_addr = &ulf,
- .i_len = sizeof(ulf),
- .i_type = XLOG_REG_TYPE_UNMOUNT,
- };
- struct xfs_log_vec vec = {
- .lv_niovecs = 1,
- .lv_iovecp = ®,
- };
- /* account for space used by record data */
- ticket->t_curr_res -= sizeof(ulf);
- return xlog_write(log, &vec, ticket, lsn, NULL, flags, false);
- }
- /*
- * Mark the filesystem clean by writing an unmount record to the head of the
- * log.
- */
- static void
- xlog_unmount_write(
- struct xlog *log)
- {
- struct xfs_mount *mp = log->l_mp;
- struct xlog_in_core *iclog;
- struct xlog_ticket *tic = NULL;
- xfs_lsn_t lsn;
- uint flags = XLOG_UNMOUNT_TRANS;
- int error;
- error = xfs_log_reserve(mp, 600, 1, &tic, XFS_LOG, 0);
- if (error)
- goto out_err;
- error = xlog_write_unmount_record(log, tic, &lsn, flags);
- /*
- * At this point, we're umounting anyway, so there's no point in
- * transitioning log state to IOERROR. Just continue...
- */
- out_err:
- if (error)
- xfs_alert(mp, "%s: unmount record failed", __func__);
- spin_lock(&log->l_icloglock);
- iclog = log->l_iclog;
- atomic_inc(&iclog->ic_refcnt);
- if (iclog->ic_state == XLOG_STATE_ACTIVE)
- xlog_state_switch_iclogs(log, iclog, 0);
- else
- ASSERT(iclog->ic_state == XLOG_STATE_WANT_SYNC ||
- iclog->ic_state == XLOG_STATE_IOERROR);
- error = xlog_state_release_iclog(log, iclog);
- xlog_wait_on_iclog(iclog);
- if (tic) {
- trace_xfs_log_umount_write(log, tic);
- xfs_log_ticket_ungrant(log, tic);
- }
- }
- static void
- xfs_log_unmount_verify_iclog(
- struct xlog *log)
- {
- struct xlog_in_core *iclog = log->l_iclog;
- do {
- ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);
- ASSERT(iclog->ic_offset == 0);
- } while ((iclog = iclog->ic_next) != log->l_iclog);
- }
- /*
- * Unmount record used to have a string "Unmount filesystem--" in the
- * data section where the "Un" was really a magic number (XLOG_UNMOUNT_TYPE).
- * We just write the magic number now since that particular field isn't
- * currently architecture converted and "Unmount" is a bit foo.
- * As far as I know, there weren't any dependencies on the old behaviour.
- */
- static void
- xfs_log_unmount_write(
- struct xfs_mount *mp)
- {
- struct xlog *log = mp->m_log;
- /*
- * Don't write out unmount record on norecovery mounts or ro devices.
- * Or, if we are doing a forced umount (typically because of IO errors).
- */
- if (mp->m_flags & XFS_MOUNT_NORECOVERY ||
- xfs_readonly_buftarg(log->l_targ)) {
- ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
- return;
- }
- xfs_log_force(mp, XFS_LOG_SYNC);
- if (XLOG_FORCED_SHUTDOWN(log))
- return;
- /*
- * If we think the summary counters are bad, avoid writing the unmount
- * record to force log recovery at next mount, after which the summary
- * counters will be recalculated. Refer to xlog_check_unmount_rec for
- * more details.
- */
- if (XFS_TEST_ERROR(xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS), mp,
- XFS_ERRTAG_FORCE_SUMMARY_RECALC)) {
- xfs_alert(mp, "%s: will fix summary counters at next mount",
- __func__);
- return;
- }
- xfs_log_unmount_verify_iclog(log);
- xlog_unmount_write(log);
- }
- /*
- * Empty the log for unmount/freeze.
- *
- * To do this, we first need to shut down the background log work so it is not
- * trying to cover the log as we clean up. We then need to unpin all objects in
- * the log so we can then flush them out. Once they have completed their IO and
- * run the callbacks removing themselves from the AIL, we can write the unmount
- * record.
- */
- void
- xfs_log_quiesce(
- struct xfs_mount *mp)
- {
- cancel_delayed_work_sync(&mp->m_log->l_work);
- xfs_log_force(mp, XFS_LOG_SYNC);
- /*
- * The superblock buffer is uncached and while xfs_ail_push_all_sync()
- * will push it, xfs_wait_buftarg() will not wait for it. Further,
- * xfs_buf_iowait() cannot be used because it was pushed with the
- * XBF_ASYNC flag set, so we need to use a lock/unlock pair to wait for
- * the IO to complete.
- */
- xfs_ail_push_all_sync(mp->m_ail);
- xfs_wait_buftarg(mp->m_ddev_targp);
- xfs_buf_lock(mp->m_sb_bp);
- xfs_buf_unlock(mp->m_sb_bp);
- xfs_log_unmount_write(mp);
- }
- /*
- * Shut down and release the AIL and Log.
- *
- * During unmount, we need to ensure we flush all the dirty metadata objects
- * from the AIL so that the log is empty before we write the unmount record to
- * the log. Once this is done, we can tear down the AIL and the log.
- */
- void
- xfs_log_unmount(
- struct xfs_mount *mp)
- {
- xfs_log_quiesce(mp);
- xfs_trans_ail_destroy(mp);
- xfs_sysfs_del(&mp->m_log->l_kobj);
- xlog_dealloc_log(mp->m_log);
- }
- void
- xfs_log_item_init(
- struct xfs_mount *mp,
- struct xfs_log_item *item,
- int type,
- const struct xfs_item_ops *ops)
- {
- item->li_mountp = mp;
- item->li_ailp = mp->m_ail;
- item->li_type = type;
- item->li_ops = ops;
- item->li_lv = NULL;
- INIT_LIST_HEAD(&item->li_ail);
- INIT_LIST_HEAD(&item->li_cil);
- INIT_LIST_HEAD(&item->li_bio_list);
- INIT_LIST_HEAD(&item->li_trans);
- }
- /*
- * Wake up processes waiting for log space after we have moved the log tail.
- */
- void
- xfs_log_space_wake(
- struct xfs_mount *mp)
- {
- struct xlog *log = mp->m_log;
- int free_bytes;
- if (XLOG_FORCED_SHUTDOWN(log))
- return;
- if (!list_empty_careful(&log->l_write_head.waiters)) {
- ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY));
- spin_lock(&log->l_write_head.lock);
- free_bytes = xlog_space_left(log, &log->l_write_head.grant);
- xlog_grant_head_wake(log, &log->l_write_head, &free_bytes);
- spin_unlock(&log->l_write_head.lock);
- }
- if (!list_empty_careful(&log->l_reserve_head.waiters)) {
- ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY));
- spin_lock(&log->l_reserve_head.lock);
- free_bytes = xlog_space_left(log, &log->l_reserve_head.grant);
- xlog_grant_head_wake(log, &log->l_reserve_head, &free_bytes);
- spin_unlock(&log->l_reserve_head.lock);
- }
- }
- /*
- * Determine if we have a transaction that has gone to disk that needs to be
- * covered. To begin the transition to the idle state firstly the log needs to
- * be idle. That means the CIL, the AIL and the iclogs needs to be empty before
- * we start attempting to cover the log.
- *
- * Only if we are then in a state where covering is needed, the caller is
- * informed that dummy transactions are required to move the log into the idle
- * state.
- *
- * If there are any items in the AIl or CIL, then we do not want to attempt to
- * cover the log as we may be in a situation where there isn't log space
- * available to run a dummy transaction and this can lead to deadlocks when the
- * tail of the log is pinned by an item that is modified in the CIL. Hence
- * there's no point in running a dummy transaction at this point because we
- * can't start trying to idle the log until both the CIL and AIL are empty.
- */
- static int
- xfs_log_need_covered(xfs_mount_t *mp)
- {
- struct xlog *log = mp->m_log;
- int needed = 0;
- if (!xfs_fs_writable(mp, SB_FREEZE_WRITE))
- return 0;
- if (!xlog_cil_empty(log))
- return 0;
- spin_lock(&log->l_icloglock);
- switch (log->l_covered_state) {
- case XLOG_STATE_COVER_DONE:
- case XLOG_STATE_COVER_DONE2:
- case XLOG_STATE_COVER_IDLE:
- break;
- case XLOG_STATE_COVER_NEED:
- case XLOG_STATE_COVER_NEED2:
- if (xfs_ail_min_lsn(log->l_ailp))
- break;
- if (!xlog_iclogs_empty(log))
- break;
- needed = 1;
- if (log->l_covered_state == XLOG_STATE_COVER_NEED)
- log->l_covered_state = XLOG_STATE_COVER_DONE;
- else
- log->l_covered_state = XLOG_STATE_COVER_DONE2;
- break;
- default:
- needed = 1;
- break;
- }
- spin_unlock(&log->l_icloglock);
- return needed;
- }
- /*
- * We may be holding the log iclog lock upon entering this routine.
- */
- xfs_lsn_t
- xlog_assign_tail_lsn_locked(
- struct xfs_mount *mp)
- {
- struct xlog *log = mp->m_log;
- struct xfs_log_item *lip;
- xfs_lsn_t tail_lsn;
- assert_spin_locked(&mp->m_ail->ail_lock);
- /*
- * To make sure we always have a valid LSN for the log tail we keep
- * track of the last LSN which was committed in log->l_last_sync_lsn,
- * and use that when the AIL was empty.
- */
- lip = xfs_ail_min(mp->m_ail);
- if (lip)
- tail_lsn = lip->li_lsn;
- else
- tail_lsn = atomic64_read(&log->l_last_sync_lsn);
- trace_xfs_log_assign_tail_lsn(log, tail_lsn);
- atomic64_set(&log->l_tail_lsn, tail_lsn);
- return tail_lsn;
- }
- xfs_lsn_t
- xlog_assign_tail_lsn(
- struct xfs_mount *mp)
- {
- xfs_lsn_t tail_lsn;
- spin_lock(&mp->m_ail->ail_lock);
- tail_lsn = xlog_assign_tail_lsn_locked(mp);
- spin_unlock(&mp->m_ail->ail_lock);
- return tail_lsn;
- }
- /*
- * Return the space in the log between the tail and the head. The head
- * is passed in the cycle/bytes formal parms. In the special case where
- * the reserve head has wrapped passed the tail, this calculation is no
- * longer valid. In this case, just return 0 which means there is no space
- * in the log. This works for all places where this function is called
- * with the reserve head. Of course, if the write head were to ever
- * wrap the tail, we should blow up. Rather than catch this case here,
- * we depend on other ASSERTions in other parts of the code. XXXmiken
- *
- * This code also handles the case where the reservation head is behind
- * the tail. The details of this case are described below, but the end
- * result is that we return the size of the log as the amount of space left.
- */
- STATIC int
- xlog_space_left(
- struct xlog *log,
- atomic64_t *head)
- {
- int free_bytes;
- int tail_bytes;
- int tail_cycle;
- int head_cycle;
- int head_bytes;
- xlog_crack_grant_head(head, &head_cycle, &head_bytes);
- xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_bytes);
- tail_bytes = BBTOB(tail_bytes);
- if (tail_cycle == head_cycle && head_bytes >= tail_bytes)
- free_bytes = log->l_logsize - (head_bytes - tail_bytes);
- else if (tail_cycle + 1 < head_cycle)
- return 0;
- else if (tail_cycle < head_cycle) {
- ASSERT(tail_cycle == (head_cycle - 1));
- free_bytes = tail_bytes - head_bytes;
- } else {
- /*
- * The reservation head is behind the tail.
- * In this case we just want to return the size of the
- * log as the amount of space left.
- */
- xfs_alert(log->l_mp, "xlog_space_left: head behind tail");
- xfs_alert(log->l_mp,
- " tail_cycle = %d, tail_bytes = %d",
- tail_cycle, tail_bytes);
- xfs_alert(log->l_mp,
- " GH cycle = %d, GH bytes = %d",
- head_cycle, head_bytes);
- ASSERT(0);
- free_bytes = log->l_logsize;
- }
- return free_bytes;
- }
- static void
- xlog_ioend_work(
- struct work_struct *work)
- {
- struct xlog_in_core *iclog =
- container_of(work, struct xlog_in_core, ic_end_io_work);
- struct xlog *log = iclog->ic_log;
- int error;
- error = blk_status_to_errno(iclog->ic_bio.bi_status);
- #ifdef DEBUG
- /* treat writes with injected CRC errors as failed */
- if (iclog->ic_fail_crc)
- error = -EIO;
- #endif
- /*
- * Race to shutdown the filesystem if we see an error.
- */
- if (XFS_TEST_ERROR(error, log->l_mp, XFS_ERRTAG_IODONE_IOERR)) {
- xfs_alert(log->l_mp, "log I/O error %d", error);
- xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
- }
- xlog_state_done_syncing(iclog);
- bio_uninit(&iclog->ic_bio);
- /*
- * Drop the lock to signal that we are done. Nothing references the
- * iclog after this, so an unmount waiting on this lock can now tear it
- * down safely. As such, it is unsafe to reference the iclog after the
- * unlock as we could race with it being freed.
- */
- up(&iclog->ic_sema);
- }
- /*
- * Return size of each in-core log record buffer.
- *
- * All machines get 8 x 32kB buffers by default, unless tuned otherwise.
- *
- * If the filesystem blocksize is too large, we may need to choose a
- * larger size since the directory code currently logs entire blocks.
- */
- STATIC void
- xlog_get_iclog_buffer_size(
- struct xfs_mount *mp,
- struct xlog *log)
- {
- if (mp->m_logbufs <= 0)
- mp->m_logbufs = XLOG_MAX_ICLOGS;
- if (mp->m_logbsize <= 0)
- mp->m_logbsize = XLOG_BIG_RECORD_BSIZE;
- log->l_iclog_bufs = mp->m_logbufs;
- log->l_iclog_size = mp->m_logbsize;
- /*
- * # headers = size / 32k - one header holds cycles from 32k of data.
- */
- log->l_iclog_heads =
- DIV_ROUND_UP(mp->m_logbsize, XLOG_HEADER_CYCLE_SIZE);
- log->l_iclog_hsize = log->l_iclog_heads << BBSHIFT;
- }
- void
- xfs_log_work_queue(
- struct xfs_mount *mp)
- {
- queue_delayed_work(mp->m_sync_workqueue, &mp->m_log->l_work,
- msecs_to_jiffies(xfs_syncd_centisecs * 10));
- }
- /*
- * Every sync period we need to unpin all items in the AIL and push them to
- * disk. If there is nothing dirty, then we might need to cover the log to
- * indicate that the filesystem is idle.
- */
- static void
- xfs_log_worker(
- struct work_struct *work)
- {
- struct xlog *log = container_of(to_delayed_work(work),
- struct xlog, l_work);
- struct xfs_mount *mp = log->l_mp;
- /* dgc: errors ignored - not fatal and nowhere to report them */
- if (xfs_log_need_covered(mp)) {
- /*
- * Dump a transaction into the log that contains no real change.
- * This is needed to stamp the current tail LSN into the log
- * during the covering operation.
- *
- * We cannot use an inode here for this - that will push dirty
- * state back up into the VFS and then periodic inode flushing
- * will prevent log covering from making progress. Hence we
- * synchronously log the superblock instead to ensure the
- * superblock is immediately unpinned and can be written back.
- */
- xfs_sync_sb(mp, true);
- } else
- xfs_log_force(mp, 0);
- /* start pushing all the metadata that is currently dirty */
- xfs_ail_push_all(mp->m_ail);
- /* queue us up again */
- xfs_log_work_queue(mp);
- }
- /*
- * This routine initializes some of the log structure for a given mount point.
- * Its primary purpose is to fill in enough, so recovery can occur. However,
- * some other stuff may be filled in too.
- */
- STATIC struct xlog *
- xlog_alloc_log(
- struct xfs_mount *mp,
- struct xfs_buftarg *log_target,
- xfs_daddr_t blk_offset,
- int num_bblks)
- {
- struct xlog *log;
- xlog_rec_header_t *head;
- xlog_in_core_t **iclogp;
- xlog_in_core_t *iclog, *prev_iclog=NULL;
- int i;
- int error = -ENOMEM;
- uint log2_size = 0;
- log = kmem_zalloc(sizeof(struct xlog), KM_MAYFAIL);
- if (!log) {
- xfs_warn(mp, "Log allocation failed: No memory!");
- goto out;
- }
- log->l_mp = mp;
- log->l_targ = log_target;
- log->l_logsize = BBTOB(num_bblks);
- log->l_logBBstart = blk_offset;
- log->l_logBBsize = num_bblks;
- log->l_covered_state = XLOG_STATE_COVER_IDLE;
- log->l_flags |= XLOG_ACTIVE_RECOVERY;
- INIT_DELAYED_WORK(&log->l_work, xfs_log_worker);
- log->l_prev_block = -1;
- /* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */
- xlog_assign_atomic_lsn(&log->l_tail_lsn, 1, 0);
- xlog_assign_atomic_lsn(&log->l_last_sync_lsn, 1, 0);
- log->l_curr_cycle = 1; /* 0 is bad since this is initial value */
- xlog_grant_head_init(&log->l_reserve_head);
- xlog_grant_head_init(&log->l_write_head);
- error = -EFSCORRUPTED;
- if (xfs_sb_version_hassector(&mp->m_sb)) {
- log2_size = mp->m_sb.sb_logsectlog;
- if (log2_size < BBSHIFT) {
- xfs_warn(mp, "Log sector size too small (0x%x < 0x%x)",
- log2_size, BBSHIFT);
- goto out_free_log;
- }
- log2_size -= BBSHIFT;
- if (log2_size > mp->m_sectbb_log) {
- xfs_warn(mp, "Log sector size too large (0x%x > 0x%x)",
- log2_size, mp->m_sectbb_log);
- goto out_free_log;
- }
- /* for larger sector sizes, must have v2 or external log */
- if (log2_size && log->l_logBBstart > 0 &&
- !xfs_sb_version_haslogv2(&mp->m_sb)) {
- xfs_warn(mp,
- "log sector size (0x%x) invalid for configuration.",
- log2_size);
- goto out_free_log;
- }
- }
- log->l_sectBBsize = 1 << log2_size;
- xlog_get_iclog_buffer_size(mp, log);
- spin_lock_init(&log->l_icloglock);
- init_waitqueue_head(&log->l_flush_wait);
- iclogp = &log->l_iclog;
- /*
- * The amount of memory to allocate for the iclog structure is
- * rather funky due to the way the structure is defined. It is
- * done this way so that we can use different sizes for machines
- * with different amounts of memory. See the definition of
- * xlog_in_core_t in xfs_log_priv.h for details.
- */
- ASSERT(log->l_iclog_size >= 4096);
- for (i = 0; i < log->l_iclog_bufs; i++) {
- int align_mask = xfs_buftarg_dma_alignment(mp->m_logdev_targp);
- size_t bvec_size = howmany(log->l_iclog_size, PAGE_SIZE) *
- sizeof(struct bio_vec);
- iclog = kmem_zalloc(sizeof(*iclog) + bvec_size, KM_MAYFAIL);
- if (!iclog)
- goto out_free_iclog;
- *iclogp = iclog;
- iclog->ic_prev = prev_iclog;
- prev_iclog = iclog;
- iclog->ic_data = kmem_alloc_io(log->l_iclog_size, align_mask,
- KM_MAYFAIL | KM_ZERO);
- if (!iclog->ic_data)
- goto out_free_iclog;
- #ifdef DEBUG
- log->l_iclog_bak[i] = &iclog->ic_header;
- #endif
- head = &iclog->ic_header;
- memset(head, 0, sizeof(xlog_rec_header_t));
- head->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);
- head->h_version = cpu_to_be32(
- xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1);
- head->h_size = cpu_to_be32(log->l_iclog_size);
- /* new fields */
- head->h_fmt = cpu_to_be32(XLOG_FMT);
- memcpy(&head->h_fs_uuid, &mp->m_sb.sb_uuid, sizeof(uuid_t));
- iclog->ic_size = log->l_iclog_size - log->l_iclog_hsize;
- iclog->ic_state = XLOG_STATE_ACTIVE;
- iclog->ic_log = log;
- atomic_set(&iclog->ic_refcnt, 0);
- spin_lock_init(&iclog->ic_callback_lock);
- INIT_LIST_HEAD(&iclog->ic_callbacks);
- iclog->ic_datap = (char *)iclog->ic_data + log->l_iclog_hsize;
- init_waitqueue_head(&iclog->ic_force_wait);
- init_waitqueue_head(&iclog->ic_write_wait);
- INIT_WORK(&iclog->ic_end_io_work, xlog_ioend_work);
- sema_init(&iclog->ic_sema, 1);
- iclogp = &iclog->ic_next;
- }
- *iclogp = log->l_iclog; /* complete ring */
- log->l_iclog->ic_prev = prev_iclog; /* re-write 1st prev ptr */
- log->l_ioend_workqueue = alloc_workqueue("xfs-log/%s",
- WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_HIGHPRI, 0,
- mp->m_super->s_id);
- if (!log->l_ioend_workqueue)
- goto out_free_iclog;
- error = xlog_cil_init(log);
- if (error)
- goto out_destroy_workqueue;
- return log;
- out_destroy_workqueue:
- destroy_workqueue(log->l_ioend_workqueue);
- out_free_iclog:
- for (iclog = log->l_iclog; iclog; iclog = prev_iclog) {
- prev_iclog = iclog->ic_next;
- kmem_free(iclog->ic_data);
- kmem_free(iclog);
- if (prev_iclog == log->l_iclog)
- break;
- }
- out_free_log:
- kmem_free(log);
- out:
- return ERR_PTR(error);
- } /* xlog_alloc_log */
- /*
- * Write out the commit record of a transaction associated with the given
- * ticket to close off a running log write. Return the lsn of the commit record.
- */
- int
- xlog_commit_record(
- struct xlog *log,
- struct xlog_ticket *ticket,
- struct xlog_in_core **iclog,
- xfs_lsn_t *lsn)
- {
- struct xfs_log_iovec reg = {
- .i_addr = NULL,
- .i_len = 0,
- .i_type = XLOG_REG_TYPE_COMMIT,
- };
- struct xfs_log_vec vec = {
- .lv_niovecs = 1,
- .lv_iovecp = ®,
- };
- int error;
- if (XLOG_FORCED_SHUTDOWN(log))
- return -EIO;
- error = xlog_write(log, &vec, ticket, lsn, iclog, XLOG_COMMIT_TRANS,
- false);
- if (error)
- xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
- return error;
- }
- /*
- * Compute the LSN that we'd need to push the log tail towards in order to have
- * (a) enough on-disk log space to log the number of bytes specified, (b) at
- * least 25% of the log space free, and (c) at least 256 blocks free. If the
- * log free space already meets all three thresholds, this function returns
- * NULLCOMMITLSN.
- */
- xfs_lsn_t
- xlog_grant_push_threshold(
- struct xlog *log,
- int need_bytes)
- {
- xfs_lsn_t threshold_lsn = 0;
- xfs_lsn_t last_sync_lsn;
- int free_blocks;
- int free_bytes;
- int threshold_block;
- int threshold_cycle;
- int free_threshold;
- ASSERT(BTOBB(need_bytes) < log->l_logBBsize);
- free_bytes = xlog_space_left(log, &log->l_reserve_head.grant);
- free_blocks = BTOBBT(free_bytes);
- /*
- * Set the threshold for the minimum number of free blocks in the
- * log to the maximum of what the caller needs, one quarter of the
- * log, and 256 blocks.
- */
- free_threshold = BTOBB(need_bytes);
- free_threshold = max(free_threshold, (log->l_logBBsize >> 2));
- free_threshold = max(free_threshold, 256);
- if (free_blocks >= free_threshold)
- return NULLCOMMITLSN;
- xlog_crack_atomic_lsn(&log->l_tail_lsn, &threshold_cycle,
- &threshold_block);
- threshold_block += free_threshold;
- if (threshold_block >= log->l_logBBsize) {
- threshold_block -= log->l_logBBsize;
- threshold_cycle += 1;
- }
- threshold_lsn = xlog_assign_lsn(threshold_cycle,
- threshold_block);
- /*
- * Don't pass in an lsn greater than the lsn of the last
- * log record known to be on disk. Use a snapshot of the last sync lsn
- * so that it doesn't change between the compare and the set.
- */
- last_sync_lsn = atomic64_read(&log->l_last_sync_lsn);
- if (XFS_LSN_CMP(threshold_lsn, last_sync_lsn) > 0)
- threshold_lsn = last_sync_lsn;
- return threshold_lsn;
- }
- /*
- * Push the tail of the log if we need to do so to maintain the free log space
- * thresholds set out by xlog_grant_push_threshold. We may need to adopt a
- * policy which pushes on an lsn which is further along in the log once we
- * reach the high water mark. In this manner, we would be creating a low water
- * mark.
- */
- STATIC void
- xlog_grant_push_ail(
- struct xlog *log,
- int need_bytes)
- {
- xfs_lsn_t threshold_lsn;
- threshold_lsn = xlog_grant_push_threshold(log, need_bytes);
- if (threshold_lsn == NULLCOMMITLSN || XLOG_FORCED_SHUTDOWN(log))
- return;
- /*
- * Get the transaction layer to kick the dirty buffers out to
- * disk asynchronously. No point in trying to do this if
- * the filesystem is shutting down.
- */
- xfs_ail_push(log->l_ailp, threshold_lsn);
- }
- /*
- * Stamp cycle number in every block
- */
- STATIC void
- xlog_pack_data(
- struct xlog *log,
- struct xlog_in_core *iclog,
- int roundoff)
- {
- int i, j, k;
- int size = iclog->ic_offset + roundoff;
- __be32 cycle_lsn;
- char *dp;
- cycle_lsn = CYCLE_LSN_DISK(iclog->ic_header.h_lsn);
- dp = iclog->ic_datap;
- for (i = 0; i < BTOBB(size); i++) {
- if (i >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE))
- break;
- iclog->ic_header.h_cycle_data[i] = *(__be32 *)dp;
- *(__be32 *)dp = cycle_lsn;
- dp += BBSIZE;
- }
- if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
- xlog_in_core_2_t *xhdr = iclog->ic_data;
- for ( ; i < BTOBB(size); i++) {
- j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
- k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
- xhdr[j].hic_xheader.xh_cycle_data[k] = *(__be32 *)dp;
- *(__be32 *)dp = cycle_lsn;
- dp += BBSIZE;
- }
- for (i = 1; i < log->l_iclog_heads; i++)
- xhdr[i].hic_xheader.xh_cycle = cycle_lsn;
- }
- }
- /*
- * Calculate the checksum for a log buffer.
- *
- * This is a little more complicated than it should be because the various
- * headers and the actual data are non-contiguous.
- */
- __le32
- xlog_cksum(
- struct xlog *log,
- struct xlog_rec_header *rhead,
- char *dp,
- int size)
- {
- uint32_t crc;
- /* first generate the crc for the record header ... */
- crc = xfs_start_cksum_update((char *)rhead,
- sizeof(struct xlog_rec_header),
- offsetof(struct xlog_rec_header, h_crc));
- /* ... then for additional cycle data for v2 logs ... */
- if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
- union xlog_in_core2 *xhdr = (union xlog_in_core2 *)rhead;
- int i;
- int xheads;
- xheads = DIV_ROUND_UP(size, XLOG_HEADER_CYCLE_SIZE);
- for (i = 1; i < xheads; i++) {
- crc = crc32c(crc, &xhdr[i].hic_xheader,
- sizeof(struct xlog_rec_ext_header));
- }
- }
- /* ... and finally for the payload */
- crc = crc32c(crc, dp, size);
- return xfs_end_cksum(crc);
- }
- static void
- xlog_bio_end_io(
- struct bio *bio)
- {
- struct xlog_in_core *iclog = bio->bi_private;
- queue_work(iclog->ic_log->l_ioend_workqueue,
- &iclog->ic_end_io_work);
- }
- static int
- xlog_map_iclog_data(
- struct bio *bio,
- void *data,
- size_t count)
- {
- do {
- struct page *page = kmem_to_page(data);
- unsigned int off = offset_in_page(data);
- size_t len = min_t(size_t, count, PAGE_SIZE - off);
- if (bio_add_page(bio, page, len, off) != len)
- return -EIO;
- data += len;
- count -= len;
- } while (count);
- return 0;
- }
- STATIC void
- xlog_write_iclog(
- struct xlog *log,
- struct xlog_in_core *iclog,
- uint64_t bno,
- unsigned int count,
- bool need_flush)
- {
- ASSERT(bno < log->l_logBBsize);
- /*
- * We lock the iclogbufs here so that we can serialise against I/O
- * completion during unmount. We might be processing a shutdown
- * triggered during unmount, and that can occur asynchronously to the
- * unmount thread, and hence we need to ensure that completes before
- * tearing down the iclogbufs. Hence we need to hold the buffer lock
- * across the log IO to archieve that.
- */
- down(&iclog->ic_sema);
- if (unlikely(iclog->ic_state == XLOG_STATE_IOERROR)) {
- /*
- * It would seem logical to return EIO here, but we rely on
- * the log state machine to propagate I/O errors instead of
- * doing it here. We kick of the state machine and unlock
- * the buffer manually, the code needs to be kept in sync
- * with the I/O completion path.
- */
- xlog_state_done_syncing(iclog);
- up(&iclog->ic_sema);
- return;
- }
- bio_init(&iclog->ic_bio, iclog->ic_bvec, howmany(count, PAGE_SIZE));
- bio_set_dev(&iclog->ic_bio, log->l_targ->bt_bdev);
- iclog->ic_bio.bi_iter.bi_sector = log->l_logBBstart + bno;
- iclog->ic_bio.bi_end_io = xlog_bio_end_io;
- iclog->ic_bio.bi_private = iclog;
- /*
- * We use REQ_SYNC | REQ_IDLE here to tell the block layer the are more
- * IOs coming immediately after this one. This prevents the block layer
- * writeback throttle from throttling log writes behind background
- * metadata writeback and causing priority inversions.
- */
- iclog->ic_bio.bi_opf = REQ_OP_WRITE | REQ_META | REQ_SYNC |
- REQ_IDLE | REQ_FUA;
- if (need_flush)
- iclog->ic_bio.bi_opf |= REQ_PREFLUSH;
- if (xlog_map_iclog_data(&iclog->ic_bio, iclog->ic_data, count)) {
- xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
- return;
- }
- if (is_vmalloc_addr(iclog->ic_data))
- flush_kernel_vmap_range(iclog->ic_data, count);
- /*
- * If this log buffer would straddle the end of the log we will have
- * to split it up into two bios, so that we can continue at the start.
- */
- if (bno + BTOBB(count) > log->l_logBBsize) {
- struct bio *split;
- split = bio_split(&iclog->ic_bio, log->l_logBBsize - bno,
- GFP_NOIO, &fs_bio_set);
- bio_chain(split, &iclog->ic_bio);
- submit_bio(split);
- /* restart at logical offset zero for the remainder */
- iclog->ic_bio.bi_iter.bi_sector = log->l_logBBstart;
- }
- submit_bio(&iclog->ic_bio);
- }
- /*
- * We need to bump cycle number for the part of the iclog that is
- * written to the start of the log. Watch out for the header magic
- * number case, though.
- */
- static void
- xlog_split_iclog(
- struct xlog *log,
- void *data,
- uint64_t bno,
- unsigned int count)
- {
- unsigned int split_offset = BBTOB(log->l_logBBsize - bno);
- unsigned int i;
- for (i = split_offset; i < count; i += BBSIZE) {
- uint32_t cycle = get_unaligned_be32(data + i);
- if (++cycle == XLOG_HEADER_MAGIC_NUM)
- cycle++;
- put_unaligned_be32(cycle, data + i);
- }
- }
- static int
- xlog_calc_iclog_size(
- struct xlog *log,
- struct xlog_in_core *iclog,
- uint32_t *roundoff)
- {
- uint32_t count_init, count;
- bool use_lsunit;
- use_lsunit = xfs_sb_version_haslogv2(&log->l_mp->m_sb) &&
- log->l_mp->m_sb.sb_logsunit > 1;
- /* Add for LR header */
- count_init = log->l_iclog_hsize + iclog->ic_offset;
- /* Round out the log write size */
- if (use_lsunit) {
- /* we have a v2 stripe unit to use */
- count = XLOG_LSUNITTOB(log, XLOG_BTOLSUNIT(log, count_init));
- } else {
- count = BBTOB(BTOBB(count_init));
- }
- ASSERT(count >= count_init);
- *roundoff = count - count_init;
- if (use_lsunit)
- ASSERT(*roundoff < log->l_mp->m_sb.sb_logsunit);
- else
- ASSERT(*roundoff < BBTOB(1));
- return count;
- }
- /*
- * Flush out the in-core log (iclog) to the on-disk log in an asynchronous
- * fashion. Previously, we should have moved the current iclog
- * ptr in the log to point to the next available iclog. This allows further
- * write to continue while this code syncs out an iclog ready to go.
- * Before an in-core log can be written out, the data section must be scanned
- * to save away the 1st word of each BBSIZE block into the header. We replace
- * it with the current cycle count. Each BBSIZE block is tagged with the
- * cycle count because there in an implicit assumption that drives will
- * guarantee that entire 512 byte blocks get written at once. In other words,
- * we can't have part of a 512 byte block written and part not written. By
- * tagging each block, we will know which blocks are valid when recovering
- * after an unclean shutdown.
- *
- * This routine is single threaded on the iclog. No other thread can be in
- * this routine with the same iclog. Changing contents of iclog can there-
- * fore be done without grabbing the state machine lock. Updating the global
- * log will require grabbing the lock though.
- *
- * The entire log manager uses a logical block numbering scheme. Only
- * xlog_write_iclog knows about the fact that the log may not start with
- * block zero on a given device.
- */
- STATIC void
- xlog_sync(
- struct xlog *log,
- struct xlog_in_core *iclog)
- {
- unsigned int count; /* byte count of bwrite */
- unsigned int roundoff; /* roundoff to BB or stripe */
- uint64_t bno;
- unsigned int size;
- bool need_flush = true, split = false;
- ASSERT(atomic_read(&iclog->ic_refcnt) == 0);
- count = xlog_calc_iclog_size(log, iclog, &roundoff);
- /* move grant heads by roundoff in sync */
- xlog_grant_add_space(log, &log->l_reserve_head.grant, roundoff);
- xlog_grant_add_space(log, &log->l_write_head.grant, roundoff);
- /* put cycle number in every block */
- xlog_pack_data(log, iclog, roundoff);
- /* real byte length */
- size = iclog->ic_offset;
- if (xfs_sb_version_haslogv2(&log->l_mp->m_sb))
- size += roundoff;
- iclog->ic_header.h_len = cpu_to_be32(size);
- XFS_STATS_INC(log->l_mp, xs_log_writes);
- XFS_STATS_ADD(log->l_mp, xs_log_blocks, BTOBB(count));
- bno = BLOCK_LSN(be64_to_cpu(iclog->ic_header.h_lsn));
- /* Do we need to split this write into 2 parts? */
- if (bno + BTOBB(count) > log->l_logBBsize) {
- xlog_split_iclog(log, &iclog->ic_header, bno, count);
- split = true;
- }
- /* calculcate the checksum */
- iclog->ic_header.h_crc = xlog_cksum(log, &iclog->ic_header,
- iclog->ic_datap, size);
- /*
- * Intentionally corrupt the log record CRC based on the error injection
- * frequency, if defined. This facilitates testing log recovery in the
- * event of torn writes. Hence, set the IOABORT state to abort the log
- * write on I/O completion and shutdown the fs. The subsequent mount
- * detects the bad CRC and attempts to recover.
- */
- #ifdef DEBUG
- if (XFS_TEST_ERROR(false, log->l_mp, XFS_ERRTAG_LOG_BAD_CRC)) {
- iclog->ic_header.h_crc &= cpu_to_le32(0xAAAAAAAA);
- iclog->ic_fail_crc = true;
- xfs_warn(log->l_mp,
- "Intentionally corrupted log record at LSN 0x%llx. Shutdown imminent.",
- be64_to_cpu(iclog->ic_header.h_lsn));
- }
- #endif
- /*
- * Flush the data device before flushing the log to make sure all meta
- * data written back from the AIL actually made it to disk before
- * stamping the new log tail LSN into the log buffer. For an external
- * log we need to issue the flush explicitly, and unfortunately
- * synchronously here; for an internal log we can simply use the block
- * layer state machine for preflushes.
- */
- if (log->l_targ != log->l_mp->m_ddev_targp || split) {
- xfs_blkdev_issue_flush(log->l_mp->m_ddev_targp);
- need_flush = false;
- }
- xlog_verify_iclog(log, iclog, count);
- xlog_write_iclog(log, iclog, bno, count, need_flush);
- }
- /*
- * Deallocate a log structure
- */
- STATIC void
- xlog_dealloc_log(
- struct xlog *log)
- {
- xlog_in_core_t *iclog, *next_iclog;
- int i;
- xlog_cil_destroy(log);
- /*
- * Cycle all the iclogbuf locks to make sure all log IO completion
- * is done before we tear down these buffers.
- */
- iclog = log->l_iclog;
- for (i = 0; i < log->l_iclog_bufs; i++) {
- down(&iclog->ic_sema);
- up(&iclog->ic_sema);
- iclog = iclog->ic_next;
- }
- iclog = log->l_iclog;
- for (i = 0; i < log->l_iclog_bufs; i++) {
- next_iclog = iclog->ic_next;
- kmem_free(iclog->ic_data);
- kmem_free(iclog);
- iclog = next_iclog;
- }
- log->l_mp->m_log = NULL;
- destroy_workqueue(log->l_ioend_workqueue);
- kmem_free(log);
- }
- /*
- * Update counters atomically now that memcpy is done.
- */
- static inline void
- xlog_state_finish_copy(
- struct xlog *log,
- struct xlog_in_core *iclog,
- int record_cnt,
- int copy_bytes)
- {
- lockdep_assert_held(&log->l_icloglock);
- be32_add_cpu(&iclog->ic_header.h_num_logops, record_cnt);
- iclog->ic_offset += copy_bytes;
- }
- /*
- * print out info relating to regions written which consume
- * the reservation
- */
- void
- xlog_print_tic_res(
- struct xfs_mount *mp,
- struct xlog_ticket *ticket)
- {
- uint i;
- uint ophdr_spc = ticket->t_res_num_ophdrs * (uint)sizeof(xlog_op_header_t);
- /* match with XLOG_REG_TYPE_* in xfs_log.h */
- #define REG_TYPE_STR(type, str) [XLOG_REG_TYPE_##type] = str
- static char *res_type_str[] = {
- REG_TYPE_STR(BFORMAT, "bformat"),
- REG_TYPE_STR(BCHUNK, "bchunk"),
- REG_TYPE_STR(EFI_FORMAT, "efi_format"),
- REG_TYPE_STR(EFD_FORMAT, "efd_format"),
- REG_TYPE_STR(IFORMAT, "iformat"),
- REG_TYPE_STR(ICORE, "icore"),
- REG_TYPE_STR(IEXT, "iext"),
- REG_TYPE_STR(IBROOT, "ibroot"),
- REG_TYPE_STR(ILOCAL, "ilocal"),
- REG_TYPE_STR(IATTR_EXT, "iattr_ext"),
- REG_TYPE_STR(IATTR_BROOT, "iattr_broot"),
- REG_TYPE_STR(IATTR_LOCAL, "iattr_local"),
- REG_TYPE_STR(QFORMAT, "qformat"),
- REG_TYPE_STR(DQUOT, "dquot"),
- REG_TYPE_STR(QUOTAOFF, "quotaoff"),
- REG_TYPE_STR(LRHEADER, "LR header"),
- REG_TYPE_STR(UNMOUNT, "unmount"),
- REG_TYPE_STR(COMMIT, "commit"),
- REG_TYPE_STR(TRANSHDR, "trans header"),
- REG_TYPE_STR(ICREATE, "inode create"),
- REG_TYPE_STR(RUI_FORMAT, "rui_format"),
- REG_TYPE_STR(RUD_FORMAT, "rud_format"),
- REG_TYPE_STR(CUI_FORMAT, "cui_format"),
- REG_TYPE_STR(CUD_FORMAT, "cud_format"),
- REG_TYPE_STR(BUI_FORMAT, "bui_format"),
- REG_TYPE_STR(BUD_FORMAT, "bud_format"),
- };
- BUILD_BUG_ON(ARRAY_SIZE(res_type_str) != XLOG_REG_TYPE_MAX + 1);
- #undef REG_TYPE_STR
- xfs_warn(mp, "ticket reservation summary:");
- xfs_warn(mp, " unit res = %d bytes",
- ticket->t_unit_res);
- xfs_warn(mp, " current res = %d bytes",
- ticket->t_curr_res);
- xfs_warn(mp, " total reg = %u bytes (o/flow = %u bytes)",
- ticket->t_res_arr_sum, ticket->t_res_o_flow);
- xfs_warn(mp, " ophdrs = %u (ophdr space = %u bytes)",
- ticket->t_res_num_ophdrs, ophdr_spc);
- xfs_warn(mp, " ophdr + reg = %u bytes",
- ticket->t_res_arr_sum + ticket->t_res_o_flow + ophdr_spc);
- xfs_warn(mp, " num regions = %u",
- ticket->t_res_num);
- for (i = 0; i < ticket->t_res_num; i++) {
- uint r_type = ticket->t_res_arr[i].r_type;
- xfs_warn(mp, "region[%u]: %s - %u bytes", i,
- ((r_type <= 0 || r_type > XLOG_REG_TYPE_MAX) ?
- "bad-rtype" : res_type_str[r_type]),
- ticket->t_res_arr[i].r_len);
- }
- }
- /*
- * Print a summary of the transaction.
- */
- void
- xlog_print_trans(
- struct xfs_trans *tp)
- {
- struct xfs_mount *mp = tp->t_mountp;
- struct xfs_log_item *lip;
- /* dump core transaction and ticket info */
- xfs_warn(mp, "transaction summary:");
- xfs_warn(mp, " log res = %d", tp->t_log_res);
- xfs_warn(mp, " log count = %d", tp->t_log_count);
- xfs_warn(mp, " flags = 0x%x", tp->t_flags);
- xlog_print_tic_res(mp, tp->t_ticket);
- /* dump each log item */
- list_for_each_entry(lip, &tp->t_items, li_trans) {
- struct xfs_log_vec *lv = lip->li_lv;
- struct xfs_log_iovec *vec;
- int i;
- xfs_warn(mp, "log item: ");
- xfs_warn(mp, " type = 0x%x", lip->li_type);
- xfs_warn(mp, " flags = 0x%lx", lip->li_flags);
- if (!lv)
- continue;
- xfs_warn(mp, " niovecs = %d", lv->lv_niovecs);
- xfs_warn(mp, " size = %d", lv->lv_size);
- xfs_warn(mp, " bytes = %d", lv->lv_bytes);
- xfs_warn(mp, " buf len = %d", lv->lv_buf_len);
- /* dump each iovec for the log item */
- vec = lv->lv_iovecp;
- for (i = 0; i < lv->lv_niovecs; i++) {
- int dumplen = min(vec->i_len, 32);
- xfs_warn(mp, " iovec[%d]", i);
- xfs_warn(mp, " type = 0x%x", vec->i_type);
- xfs_warn(mp, " len = %d", vec->i_len);
- xfs_warn(mp, " first %d bytes of iovec[%d]:", dumplen, i);
- xfs_hex_dump(vec->i_addr, dumplen);
- vec++;
- }
- }
- }
- /*
- * Calculate the potential space needed by the log vector. We may need a start
- * record, and each region gets its own struct xlog_op_header and may need to be
- * double word aligned.
- */
- static int
- xlog_write_calc_vec_length(
- struct xlog_ticket *ticket,
- struct xfs_log_vec *log_vector,
- bool need_start_rec)
- {
- struct xfs_log_vec *lv;
- int headers = need_start_rec ? 1 : 0;
- int len = 0;
- int i;
- for (lv = log_vector; lv; lv = lv->lv_next) {
- /* we don't write ordered log vectors */
- if (lv->lv_buf_len == XFS_LOG_VEC_ORDERED)
- continue;
- headers += lv->lv_niovecs;
- for (i = 0; i < lv->lv_niovecs; i++) {
- struct xfs_log_iovec *vecp = &lv->lv_iovecp[i];
- len += vecp->i_len;
- xlog_tic_add_region(ticket, vecp->i_len, vecp->i_type);
- }
- }
- ticket->t_res_num_ophdrs += headers;
- len += headers * sizeof(struct xlog_op_header);
- return len;
- }
- static void
- xlog_write_start_rec(
- struct xlog_op_header *ophdr,
- struct xlog_ticket *ticket)
- {
- ophdr->oh_tid = cpu_to_be32(ticket->t_tid);
- ophdr->oh_clientid = ticket->t_clientid;
- ophdr->oh_len = 0;
- ophdr->oh_flags = XLOG_START_TRANS;
- ophdr->oh_res2 = 0;
- }
- static xlog_op_header_t *
- xlog_write_setup_ophdr(
- struct xlog *log,
- struct xlog_op_header *ophdr,
- struct xlog_ticket *ticket,
- uint flags)
- {
- ophdr->oh_tid = cpu_to_be32(ticket->t_tid);
- ophdr->oh_clientid = ticket->t_clientid;
- ophdr->oh_res2 = 0;
- /* are we copying a commit or unmount record? */
- ophdr->oh_flags = flags;
- /*
- * We've seen logs corrupted with bad transaction client ids. This
- * makes sure that XFS doesn't generate them on. Turn this into an EIO
- * and shut down the filesystem.
- */
- switch (ophdr->oh_clientid) {
- case XFS_TRANSACTION:
- case XFS_VOLUME:
- case XFS_LOG:
- break;
- default:
- xfs_warn(log->l_mp,
- "Bad XFS transaction clientid 0x%x in ticket "PTR_FMT,
- ophdr->oh_clientid, ticket);
- return NULL;
- }
- return ophdr;
- }
- /*
- * Set up the parameters of the region copy into the log. This has
- * to handle region write split across multiple log buffers - this
- * state is kept external to this function so that this code can
- * be written in an obvious, self documenting manner.
- */
- static int
- xlog_write_setup_copy(
- struct xlog_ticket *ticket,
- struct xlog_op_header *ophdr,
- int space_available,
- int space_required,
- int *copy_off,
- int *copy_len,
- int *last_was_partial_copy,
- int *bytes_consumed)
- {
- int still_to_copy;
- still_to_copy = space_required - *bytes_consumed;
- *copy_off = *bytes_consumed;
- if (still_to_copy <= space_available) {
- /* write of region completes here */
- *copy_len = still_to_copy;
- ophdr->oh_len = cpu_to_be32(*copy_len);
- if (*last_was_partial_copy)
- ophdr->oh_flags |= (XLOG_END_TRANS|XLOG_WAS_CONT_TRANS);
- *last_was_partial_copy = 0;
- *bytes_consumed = 0;
- return 0;
- }
- /* partial write of region, needs extra log op header reservation */
- *copy_len = space_available;
- ophdr->oh_len = cpu_to_be32(*copy_len);
- ophdr->oh_flags |= XLOG_CONTINUE_TRANS;
- if (*last_was_partial_copy)
- ophdr->oh_flags |= XLOG_WAS_CONT_TRANS;
- *bytes_consumed += *copy_len;
- (*last_was_partial_copy)++;
- /* account for new log op header */
- ticket->t_curr_res -= sizeof(struct xlog_op_header);
- ticket->t_res_num_ophdrs++;
- return sizeof(struct xlog_op_header);
- }
- static int
- xlog_write_copy_finish(
- struct xlog *log,
- struct xlog_in_core *iclog,
- uint flags,
- int *record_cnt,
- int *data_cnt,
- int *partial_copy,
- int *partial_copy_len,
- int log_offset,
- struct xlog_in_core **commit_iclog)
- {
- int error;
- if (*partial_copy) {
- /*
- * This iclog has already been marked WANT_SYNC by
- * xlog_state_get_iclog_space.
- */
- spin_lock(&log->l_icloglock);
- xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt);
- *record_cnt = 0;
- *data_cnt = 0;
- goto release_iclog;
- }
- *partial_copy = 0;
- *partial_copy_len = 0;
- if (iclog->ic_size - log_offset <= sizeof(xlog_op_header_t)) {
- /* no more space in this iclog - push it. */
- spin_lock(&log->l_icloglock);
- xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt);
- *record_cnt = 0;
- *data_cnt = 0;
- if (iclog->ic_state == XLOG_STATE_ACTIVE)
- xlog_state_switch_iclogs(log, iclog, 0);
- else
- ASSERT(iclog->ic_state == XLOG_STATE_WANT_SYNC ||
- iclog->ic_state == XLOG_STATE_IOERROR);
- if (!commit_iclog)
- goto release_iclog;
- spin_unlock(&log->l_icloglock);
- ASSERT(flags & XLOG_COMMIT_TRANS);
- *commit_iclog = iclog;
- }
- return 0;
- release_iclog:
- error = xlog_state_release_iclog(log, iclog);
- spin_unlock(&log->l_icloglock);
- return error;
- }
- /*
- * Write some region out to in-core log
- *
- * This will be called when writing externally provided regions or when
- * writing out a commit record for a given transaction.
- *
- * General algorithm:
- * 1. Find total length of this write. This may include adding to the
- * lengths passed in.
- * 2. Check whether we violate the tickets reservation.
- * 3. While writing to this iclog
- * A. Reserve as much space in this iclog as can get
- * B. If this is first write, save away start lsn
- * C. While writing this region:
- * 1. If first write of transaction, write start record
- * 2. Write log operation header (header per region)
- * 3. Find out if we can fit entire region into this iclog
- * 4. Potentially, verify destination memcpy ptr
- * 5. Memcpy (partial) region
- * 6. If partial copy, release iclog; otherwise, continue
- * copying more regions into current iclog
- * 4. Mark want sync bit (in simulation mode)
- * 5. Release iclog for potential flush to on-disk log.
- *
- * ERRORS:
- * 1. Panic if reservation is overrun. This should never happen since
- * reservation amounts are generated internal to the filesystem.
- * NOTES:
- * 1. Tickets are single threaded data structures.
- * 2. The XLOG_END_TRANS & XLOG_CONTINUE_TRANS flags are passed down to the
- * syncing routine. When a single log_write region needs to span
- * multiple in-core logs, the XLOG_CONTINUE_TRANS bit should be set
- * on all log operation writes which don't contain the end of the
- * region. The XLOG_END_TRANS bit is used for the in-core log
- * operation which contains the end of the continued log_write region.
- * 3. When xlog_state_get_iclog_space() grabs the rest of the current iclog,
- * we don't really know exactly how much space will be used. As a result,
- * we don't update ic_offset until the end when we know exactly how many
- * bytes have been written out.
- */
- int
- xlog_write(
- struct xlog *log,
- struct xfs_log_vec *log_vector,
- struct xlog_ticket *ticket,
- xfs_lsn_t *start_lsn,
- struct xlog_in_core **commit_iclog,
- uint flags,
- bool need_start_rec)
- {
- struct xlog_in_core *iclog = NULL;
- struct xfs_log_vec *lv = log_vector;
- struct xfs_log_iovec *vecp = lv->lv_iovecp;
- int index = 0;
- int len;
- int partial_copy = 0;
- int partial_copy_len = 0;
- int contwr = 0;
- int record_cnt = 0;
- int data_cnt = 0;
- int error = 0;
- /*
- * If this is a commit or unmount transaction, we don't need a start
- * record to be written. We do, however, have to account for the
- * commit or unmount header that gets written. Hence we always have
- * to account for an extra xlog_op_header here.
- */
- ticket->t_curr_res -= sizeof(struct xlog_op_header);
- if (ticket->t_curr_res < 0) {
- xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES,
- "ctx ticket reservation ran out. Need to up reservation");
- xlog_print_tic_res(log->l_mp, ticket);
- xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
- }
- len = xlog_write_calc_vec_length(ticket, log_vector, need_start_rec);
- *start_lsn = 0;
- while (lv && (!lv->lv_niovecs || index < lv->lv_niovecs)) {
- void *ptr;
- int log_offset;
- error = xlog_state_get_iclog_space(log, len, &iclog, ticket,
- &contwr, &log_offset);
- if (error)
- return error;
- ASSERT(log_offset <= iclog->ic_size - 1);
- ptr = iclog->ic_datap + log_offset;
- /* start_lsn is the first lsn written to. That's all we need. */
- if (!*start_lsn)
- *start_lsn = be64_to_cpu(iclog->ic_header.h_lsn);
- /*
- * This loop writes out as many regions as can fit in the amount
- * of space which was allocated by xlog_state_get_iclog_space().
- */
- while (lv && (!lv->lv_niovecs || index < lv->lv_niovecs)) {
- struct xfs_log_iovec *reg;
- struct xlog_op_header *ophdr;
- int copy_len;
- int copy_off;
- bool ordered = false;
- /* ordered log vectors have no regions to write */
- if (lv->lv_buf_len == XFS_LOG_VEC_ORDERED) {
- ASSERT(lv->lv_niovecs == 0);
- ordered = true;
- goto next_lv;
- }
- reg = &vecp[index];
- ASSERT(reg->i_len % sizeof(int32_t) == 0);
- ASSERT((unsigned long)ptr % sizeof(int32_t) == 0);
- /*
- * Before we start formatting log vectors, we need to
- * write a start record. Only do this for the first
- * iclog we write to.
- */
- if (need_start_rec) {
- xlog_write_start_rec(ptr, ticket);
- xlog_write_adv_cnt(&ptr, &len, &log_offset,
- sizeof(struct xlog_op_header));
- }
- ophdr = xlog_write_setup_ophdr(log, ptr, ticket, flags);
- if (!ophdr)
- return -EIO;
- xlog_write_adv_cnt(&ptr, &len, &log_offset,
- sizeof(struct xlog_op_header));
- len += xlog_write_setup_copy(ticket, ophdr,
- iclog->ic_size-log_offset,
- reg->i_len,
- ©_off, ©_len,
- &partial_copy,
- &partial_copy_len);
- xlog_verify_dest_ptr(log, ptr);
- /*
- * Copy region.
- *
- * Unmount records just log an opheader, so can have
- * empty payloads with no data region to copy. Hence we
- * only copy the payload if the vector says it has data
- * to copy.
- */
- ASSERT(copy_len >= 0);
- if (copy_len > 0) {
- memcpy(ptr, reg->i_addr + copy_off, copy_len);
- xlog_write_adv_cnt(&ptr, &len, &log_offset,
- copy_len);
- }
- copy_len += sizeof(struct xlog_op_header);
- record_cnt++;
- if (need_start_rec) {
- copy_len += sizeof(struct xlog_op_header);
- record_cnt++;
- need_start_rec = false;
- }
- data_cnt += contwr ? copy_len : 0;
- error = xlog_write_copy_finish(log, iclog, flags,
- &record_cnt, &data_cnt,
- &partial_copy,
- &partial_copy_len,
- log_offset,
- commit_iclog);
- if (error)
- return error;
- /*
- * if we had a partial copy, we need to get more iclog
- * space but we don't want to increment the region
- * index because there is still more is this region to
- * write.
- *
- * If we completed writing this region, and we flushed
- * the iclog (indicated by resetting of the record
- * count), then we also need to get more log space. If
- * this was the last record, though, we are done and
- * can just return.
- */
- if (partial_copy)
- break;
- if (++index == lv->lv_niovecs) {
- next_lv:
- lv = lv->lv_next;
- index = 0;
- if (lv)
- vecp = lv->lv_iovecp;
- }
- if (record_cnt == 0 && !ordered) {
- if (!lv)
- return 0;
- break;
- }
- }
- }
- ASSERT(len == 0);
- spin_lock(&log->l_icloglock);
- xlog_state_finish_copy(log, iclog, record_cnt, data_cnt);
- if (commit_iclog) {
- ASSERT(flags & XLOG_COMMIT_TRANS);
- *commit_iclog = iclog;
- } else {
- error = xlog_state_release_iclog(log, iclog);
- }
- spin_unlock(&log->l_icloglock);
- return error;
- }
- static void
- xlog_state_activate_iclog(
- struct xlog_in_core *iclog,
- int *iclogs_changed)
- {
- ASSERT(list_empty_careful(&iclog->ic_callbacks));
- /*
- * If the number of ops in this iclog indicate it just contains the
- * dummy transaction, we can change state into IDLE (the second time
- * around). Otherwise we should change the state into NEED a dummy.
- * We don't need to cover the dummy.
- */
- if (*iclogs_changed == 0 &&
- iclog->ic_header.h_num_logops == cpu_to_be32(XLOG_COVER_OPS)) {
- *iclogs_changed = 1;
- } else {
- /*
- * We have two dirty iclogs so start over. This could also be
- * num of ops indicating this is not the dummy going out.
- */
- *iclogs_changed = 2;
- }
- iclog->ic_state = XLOG_STATE_ACTIVE;
- iclog->ic_offset = 0;
- iclog->ic_header.h_num_logops = 0;
- memset(iclog->ic_header.h_cycle_data, 0,
- sizeof(iclog->ic_header.h_cycle_data));
- iclog->ic_header.h_lsn = 0;
- }
- /*
- * Loop through all iclogs and mark all iclogs currently marked DIRTY as
- * ACTIVE after iclog I/O has completed.
- */
- static void
- xlog_state_activate_iclogs(
- struct xlog *log,
- int *iclogs_changed)
- {
- struct xlog_in_core *iclog = log->l_iclog;
- do {
- if (iclog->ic_state == XLOG_STATE_DIRTY)
- xlog_state_activate_iclog(iclog, iclogs_changed);
- /*
- * The ordering of marking iclogs ACTIVE must be maintained, so
- * an iclog doesn't become ACTIVE beyond one that is SYNCING.
- */
- else if (iclog->ic_state != XLOG_STATE_ACTIVE)
- break;
- } while ((iclog = iclog->ic_next) != log->l_iclog);
- }
- static int
- xlog_covered_state(
- int prev_state,
- int iclogs_changed)
- {
- /*
- * We usually go to NEED. But we go to NEED2 if the changed indicates we
- * are done writing the dummy record. If we are done with the second
- * dummy recored (DONE2), then we go to IDLE.
- */
- switch (prev_state) {
- case XLOG_STATE_COVER_IDLE:
- case XLOG_STATE_COVER_NEED:
- case XLOG_STATE_COVER_NEED2:
- break;
- case XLOG_STATE_COVER_DONE:
- if (iclogs_changed == 1)
- return XLOG_STATE_COVER_NEED2;
- break;
- case XLOG_STATE_COVER_DONE2:
- if (iclogs_changed == 1)
- return XLOG_STATE_COVER_IDLE;
- break;
- default:
- ASSERT(0);
- }
- return XLOG_STATE_COVER_NEED;
- }
- STATIC void
- xlog_state_clean_iclog(
- struct xlog *log,
- struct xlog_in_core *dirty_iclog)
- {
- int iclogs_changed = 0;
- dirty_iclog->ic_state = XLOG_STATE_DIRTY;
- xlog_state_activate_iclogs(log, &iclogs_changed);
- wake_up_all(&dirty_iclog->ic_force_wait);
- if (iclogs_changed) {
- log->l_covered_state = xlog_covered_state(log->l_covered_state,
- iclogs_changed);
- }
- }
- STATIC xfs_lsn_t
- xlog_get_lowest_lsn(
- struct xlog *log)
- {
- struct xlog_in_core *iclog = log->l_iclog;
- xfs_lsn_t lowest_lsn = 0, lsn;
- do {
- if (iclog->ic_state == XLOG_STATE_ACTIVE ||
- iclog->ic_state == XLOG_STATE_DIRTY)
- continue;
- lsn = be64_to_cpu(iclog->ic_header.h_lsn);
- if ((lsn && !lowest_lsn) || XFS_LSN_CMP(lsn, lowest_lsn) < 0)
- lowest_lsn = lsn;
- } while ((iclog = iclog->ic_next) != log->l_iclog);
- return lowest_lsn;
- }
- /*
- * Completion of a iclog IO does not imply that a transaction has completed, as
- * transactions can be large enough to span many iclogs. We cannot change the
- * tail of the log half way through a transaction as this may be the only
- * transaction in the log and moving the tail to point to the middle of it
- * will prevent recovery from finding the start of the transaction. Hence we
- * should only update the last_sync_lsn if this iclog contains transaction
- * completion callbacks on it.
- *
- * We have to do this before we drop the icloglock to ensure we are the only one
- * that can update it.
- *
- * If we are moving the last_sync_lsn forwards, we also need to ensure we kick
- * the reservation grant head pushing. This is due to the fact that the push
- * target is bound by the current last_sync_lsn value. Hence if we have a large
- * amount of log space bound up in this committing transaction then the
- * last_sync_lsn value may be the limiting factor preventing tail pushing from
- * freeing space in the log. Hence once we've updated the last_sync_lsn we
- * should push the AIL to ensure the push target (and hence the grant head) is
- * no longer bound by the old log head location and can move forwards and make
- * progress again.
- */
- static void
- xlog_state_set_callback(
- struct xlog *log,
- struct xlog_in_core *iclog,
- xfs_lsn_t header_lsn)
- {
- iclog->ic_state = XLOG_STATE_CALLBACK;
- ASSERT(XFS_LSN_CMP(atomic64_read(&log->l_last_sync_lsn),
- header_lsn) <= 0);
- if (list_empty_careful(&iclog->ic_callbacks))
- return;
- atomic64_set(&log->l_last_sync_lsn, header_lsn);
- xlog_grant_push_ail(log, 0);
- }
- /*
- * Return true if we need to stop processing, false to continue to the next
- * iclog. The caller will need to run callbacks if the iclog is returned in the
- * XLOG_STATE_CALLBACK state.
- */
- static bool
- xlog_state_iodone_process_iclog(
- struct xlog *log,
- struct xlog_in_core *iclog,
- bool *ioerror)
- {
- xfs_lsn_t lowest_lsn;
- xfs_lsn_t header_lsn;
- switch (iclog->ic_state) {
- case XLOG_STATE_ACTIVE:
- case XLOG_STATE_DIRTY:
- /*
- * Skip all iclogs in the ACTIVE & DIRTY states:
- */
- return false;
- case XLOG_STATE_IOERROR:
- /*
- * Between marking a filesystem SHUTDOWN and stopping the log,
- * we do flush all iclogs to disk (if there wasn't a log I/O
- * error). So, we do want things to go smoothly in case of just
- * a SHUTDOWN w/o a LOG_IO_ERROR.
- */
- *ioerror = true;
- return false;
- case XLOG_STATE_DONE_SYNC:
- /*
- * Now that we have an iclog that is in the DONE_SYNC state, do
- * one more check here to see if we have chased our tail around.
- * If this is not the lowest lsn iclog, then we will leave it
- * for another completion to process.
- */
- header_lsn = be64_to_cpu(iclog->ic_header.h_lsn);
- lowest_lsn = xlog_get_lowest_lsn(log);
- if (lowest_lsn && XFS_LSN_CMP(lowest_lsn, header_lsn) < 0)
- return false;
- xlog_state_set_callback(log, iclog, header_lsn);
- return false;
- default:
- /*
- * Can only perform callbacks in order. Since this iclog is not
- * in the DONE_SYNC state, we skip the rest and just try to
- * clean up.
- */
- return true;
- }
- }
- /*
- * Keep processing entries in the iclog callback list until we come around and
- * it is empty. We need to atomically see that the list is empty and change the
- * state to DIRTY so that we don't miss any more callbacks being added.
- *
- * This function is called with the icloglock held and returns with it held. We
- * drop it while running callbacks, however, as holding it over thousands of
- * callbacks is unnecessary and causes excessive contention if we do.
- */
- static void
- xlog_state_do_iclog_callbacks(
- struct xlog *log,
- struct xlog_in_core *iclog)
- __releases(&log->l_icloglock)
- __acquires(&log->l_icloglock)
- {
- spin_unlock(&log->l_icloglock);
- spin_lock(&iclog->ic_callback_lock);
- while (!list_empty(&iclog->ic_callbacks)) {
- LIST_HEAD(tmp);
- list_splice_init(&iclog->ic_callbacks, &tmp);
- spin_unlock(&iclog->ic_callback_lock);
- xlog_cil_process_committed(&tmp);
- spin_lock(&iclog->ic_callback_lock);
- }
- /*
- * Pick up the icloglock while still holding the callback lock so we
- * serialise against anyone trying to add more callbacks to this iclog
- * now we've finished processing.
- */
- spin_lock(&log->l_icloglock);
- spin_unlock(&iclog->ic_callback_lock);
- }
- STATIC void
- xlog_state_do_callback(
- struct xlog *log)
- {
- struct xlog_in_core *iclog;
- struct xlog_in_core *first_iclog;
- bool cycled_icloglock;
- bool ioerror;
- int flushcnt = 0;
- int repeats = 0;
- spin_lock(&log->l_icloglock);
- do {
- /*
- * Scan all iclogs starting with the one pointed to by the
- * log. Reset this starting point each time the log is
- * unlocked (during callbacks).
- *
- * Keep looping through iclogs until one full pass is made
- * without running any callbacks.
- */
- first_iclog = log->l_iclog;
- iclog = log->l_iclog;
- cycled_icloglock = false;
- ioerror = false;
- repeats++;
- do {
- if (xlog_state_iodone_process_iclog(log, iclog,
- &ioerror))
- break;
- if (iclog->ic_state != XLOG_STATE_CALLBACK &&
- iclog->ic_state != XLOG_STATE_IOERROR) {
- iclog = iclog->ic_next;
- continue;
- }
- /*
- * Running callbacks will drop the icloglock which means
- * we'll have to run at least one more complete loop.
- */
- cycled_icloglock = true;
- xlog_state_do_iclog_callbacks(log, iclog);
- if (XLOG_FORCED_SHUTDOWN(log))
- wake_up_all(&iclog->ic_force_wait);
- else
- xlog_state_clean_iclog(log, iclog);
- iclog = iclog->ic_next;
- } while (first_iclog != iclog);
- if (repeats > 5000) {
- flushcnt += repeats;
- repeats = 0;
- xfs_warn(log->l_mp,
- "%s: possible infinite loop (%d iterations)",
- __func__, flushcnt);
- }
- } while (!ioerror && cycled_icloglock);
- if (log->l_iclog->ic_state == XLOG_STATE_ACTIVE ||
- log->l_iclog->ic_state == XLOG_STATE_IOERROR)
- wake_up_all(&log->l_flush_wait);
- spin_unlock(&log->l_icloglock);
- }
- /*
- * Finish transitioning this iclog to the dirty state.
- *
- * Make sure that we completely execute this routine only when this is
- * the last call to the iclog. There is a good chance that iclog flushes,
- * when we reach the end of the physical log, get turned into 2 separate
- * calls to bwrite. Hence, one iclog flush could generate two calls to this
- * routine. By using the reference count bwritecnt, we guarantee that only
- * the second completion goes through.
- *
- * Callbacks could take time, so they are done outside the scope of the
- * global state machine log lock.
- */
- STATIC void
- xlog_state_done_syncing(
- struct xlog_in_core *iclog)
- {
- struct xlog *log = iclog->ic_log;
- spin_lock(&log->l_icloglock);
- ASSERT(atomic_read(&iclog->ic_refcnt) == 0);
- /*
- * If we got an error, either on the first buffer, or in the case of
- * split log writes, on the second, we shut down the file system and
- * no iclogs should ever be attempted to be written to disk again.
- */
- if (!XLOG_FORCED_SHUTDOWN(log)) {
- ASSERT(iclog->ic_state == XLOG_STATE_SYNCING);
- iclog->ic_state = XLOG_STATE_DONE_SYNC;
- }
- /*
- * Someone could be sleeping prior to writing out the next
- * iclog buffer, we wake them all, one will get to do the
- * I/O, the others get to wait for the result.
- */
- wake_up_all(&iclog->ic_write_wait);
- spin_unlock(&log->l_icloglock);
- xlog_state_do_callback(log);
- }
- /*
- * If the head of the in-core log ring is not (ACTIVE or DIRTY), then we must
- * sleep. We wait on the flush queue on the head iclog as that should be
- * the first iclog to complete flushing. Hence if all iclogs are syncing,
- * we will wait here and all new writes will sleep until a sync completes.
- *
- * The in-core logs are used in a circular fashion. They are not used
- * out-of-order even when an iclog past the head is free.
- *
- * return:
- * * log_offset where xlog_write() can start writing into the in-core
- * log's data space.
- * * in-core log pointer to which xlog_write() should write.
- * * boolean indicating this is a continued write to an in-core log.
- * If this is the last write, then the in-core log's offset field
- * needs to be incremented, depending on the amount of data which
- * is copied.
- */
- STATIC int
- xlog_state_get_iclog_space(
- struct xlog *log,
- int len,
- struct xlog_in_core **iclogp,
- struct xlog_ticket *ticket,
- int *continued_write,
- int *logoffsetp)
- {
- int log_offset;
- xlog_rec_header_t *head;
- xlog_in_core_t *iclog;
- restart:
- spin_lock(&log->l_icloglock);
- if (XLOG_FORCED_SHUTDOWN(log)) {
- spin_unlock(&log->l_icloglock);
- return -EIO;
- }
- iclog = log->l_iclog;
- if (iclog->ic_state != XLOG_STATE_ACTIVE) {
- XFS_STATS_INC(log->l_mp, xs_log_noiclogs);
- /* Wait for log writes to have flushed */
- xlog_wait(&log->l_flush_wait, &log->l_icloglock);
- goto restart;
- }
- head = &iclog->ic_header;
- atomic_inc(&iclog->ic_refcnt); /* prevents sync */
- log_offset = iclog->ic_offset;
- /* On the 1st write to an iclog, figure out lsn. This works
- * if iclogs marked XLOG_STATE_WANT_SYNC always write out what they are
- * committing to. If the offset is set, that's how many blocks
- * must be written.
- */
- if (log_offset == 0) {
- ticket->t_curr_res -= log->l_iclog_hsize;
- xlog_tic_add_region(ticket,
- log->l_iclog_hsize,
- XLOG_REG_TYPE_LRHEADER);
- head->h_cycle = cpu_to_be32(log->l_curr_cycle);
- head->h_lsn = cpu_to_be64(
- xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block));
- ASSERT(log->l_curr_block >= 0);
- }
- /* If there is enough room to write everything, then do it. Otherwise,
- * claim the rest of the region and make sure the XLOG_STATE_WANT_SYNC
- * bit is on, so this will get flushed out. Don't update ic_offset
- * until you know exactly how many bytes get copied. Therefore, wait
- * until later to update ic_offset.
- *
- * xlog_write() algorithm assumes that at least 2 xlog_op_header_t's
- * can fit into remaining data section.
- */
- if (iclog->ic_size - iclog->ic_offset < 2*sizeof(xlog_op_header_t)) {
- int error = 0;
- xlog_state_switch_iclogs(log, iclog, iclog->ic_size);
- /*
- * If we are the only one writing to this iclog, sync it to
- * disk. We need to do an atomic compare and decrement here to
- * avoid racing with concurrent atomic_dec_and_lock() calls in
- * xlog_state_release_iclog() when there is more than one
- * reference to the iclog.
- */
- if (!atomic_add_unless(&iclog->ic_refcnt, -1, 1))
- error = xlog_state_release_iclog(log, iclog);
- spin_unlock(&log->l_icloglock);
- if (error)
- return error;
- goto restart;
- }
- /* Do we have enough room to write the full amount in the remainder
- * of this iclog? Or must we continue a write on the next iclog and
- * mark this iclog as completely taken? In the case where we switch
- * iclogs (to mark it taken), this particular iclog will release/sync
- * to disk in xlog_write().
- */
- if (len <= iclog->ic_size - iclog->ic_offset) {
- *continued_write = 0;
- iclog->ic_offset += len;
- } else {
- *continued_write = 1;
- xlog_state_switch_iclogs(log, iclog, iclog->ic_size);
- }
- *iclogp = iclog;
- ASSERT(iclog->ic_offset <= iclog->ic_size);
- spin_unlock(&log->l_icloglock);
- *logoffsetp = log_offset;
- return 0;
- }
- /*
- * The first cnt-1 times a ticket goes through here we don't need to move the
- * grant write head because the permanent reservation has reserved cnt times the
- * unit amount. Release part of current permanent unit reservation and reset
- * current reservation to be one units worth. Also move grant reservation head
- * forward.
- */
- void
- xfs_log_ticket_regrant(
- struct xlog *log,
- struct xlog_ticket *ticket)
- {
- trace_xfs_log_ticket_regrant(log, ticket);
- if (ticket->t_cnt > 0)
- ticket->t_cnt--;
- xlog_grant_sub_space(log, &log->l_reserve_head.grant,
- ticket->t_curr_res);
- xlog_grant_sub_space(log, &log->l_write_head.grant,
- ticket->t_curr_res);
- ticket->t_curr_res = ticket->t_unit_res;
- xlog_tic_reset_res(ticket);
- trace_xfs_log_ticket_regrant_sub(log, ticket);
- /* just return if we still have some of the pre-reserved space */
- if (!ticket->t_cnt) {
- xlog_grant_add_space(log, &log->l_reserve_head.grant,
- ticket->t_unit_res);
- trace_xfs_log_ticket_regrant_exit(log, ticket);
- ticket->t_curr_res = ticket->t_unit_res;
- xlog_tic_reset_res(ticket);
- }
- xfs_log_ticket_put(ticket);
- }
- /*
- * Give back the space left from a reservation.
- *
- * All the information we need to make a correct determination of space left
- * is present. For non-permanent reservations, things are quite easy. The
- * count should have been decremented to zero. We only need to deal with the
- * space remaining in the current reservation part of the ticket. If the
- * ticket contains a permanent reservation, there may be left over space which
- * needs to be released. A count of N means that N-1 refills of the current
- * reservation can be done before we need to ask for more space. The first
- * one goes to fill up the first current reservation. Once we run out of
- * space, the count will stay at zero and the only space remaining will be
- * in the current reservation field.
- */
- void
- xfs_log_ticket_ungrant(
- struct xlog *log,
- struct xlog_ticket *ticket)
- {
- int bytes;
- trace_xfs_log_ticket_ungrant(log, ticket);
- if (ticket->t_cnt > 0)
- ticket->t_cnt--;
- trace_xfs_log_ticket_ungrant_sub(log, ticket);
- /*
- * If this is a permanent reservation ticket, we may be able to free
- * up more space based on the remaining count.
- */
- bytes = ticket->t_curr_res;
- if (ticket->t_cnt > 0) {
- ASSERT(ticket->t_flags & XLOG_TIC_PERM_RESERV);
- bytes += ticket->t_unit_res*ticket->t_cnt;
- }
- xlog_grant_sub_space(log, &log->l_reserve_head.grant, bytes);
- xlog_grant_sub_space(log, &log->l_write_head.grant, bytes);
- trace_xfs_log_ticket_ungrant_exit(log, ticket);
- xfs_log_space_wake(log->l_mp);
- xfs_log_ticket_put(ticket);
- }
- /*
- * This routine will mark the current iclog in the ring as WANT_SYNC and move
- * the current iclog pointer to the next iclog in the ring.
- */
- STATIC void
- xlog_state_switch_iclogs(
- struct xlog *log,
- struct xlog_in_core *iclog,
- int eventual_size)
- {
- ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);
- assert_spin_locked(&log->l_icloglock);
- if (!eventual_size)
- eventual_size = iclog->ic_offset;
- iclog->ic_state = XLOG_STATE_WANT_SYNC;
- iclog->ic_header.h_prev_block = cpu_to_be32(log->l_prev_block);
- log->l_prev_block = log->l_curr_block;
- log->l_prev_cycle = log->l_curr_cycle;
- /* roll log?: ic_offset changed later */
- log->l_curr_block += BTOBB(eventual_size)+BTOBB(log->l_iclog_hsize);
- /* Round up to next log-sunit */
- if (xfs_sb_version_haslogv2(&log->l_mp->m_sb) &&
- log->l_mp->m_sb.sb_logsunit > 1) {
- uint32_t sunit_bb = BTOBB(log->l_mp->m_sb.sb_logsunit);
- log->l_curr_block = roundup(log->l_curr_block, sunit_bb);
- }
- if (log->l_curr_block >= log->l_logBBsize) {
- /*
- * Rewind the current block before the cycle is bumped to make
- * sure that the combined LSN never transiently moves forward
- * when the log wraps to the next cycle. This is to support the
- * unlocked sample of these fields from xlog_valid_lsn(). Most
- * other cases should acquire l_icloglock.
- */
- log->l_curr_block -= log->l_logBBsize;
- ASSERT(log->l_curr_block >= 0);
- smp_wmb();
- log->l_curr_cycle++;
- if (log->l_curr_cycle == XLOG_HEADER_MAGIC_NUM)
- log->l_curr_cycle++;
- }
- ASSERT(iclog == log->l_iclog);
- log->l_iclog = iclog->ic_next;
- }
- /*
- * Write out all data in the in-core log as of this exact moment in time.
- *
- * Data may be written to the in-core log during this call. However,
- * we don't guarantee this data will be written out. A change from past
- * implementation means this routine will *not* write out zero length LRs.
- *
- * Basically, we try and perform an intelligent scan of the in-core logs.
- * If we determine there is no flushable data, we just return. There is no
- * flushable data if:
- *
- * 1. the current iclog is active and has no data; the previous iclog
- * is in the active or dirty state.
- * 2. the current iclog is drity, and the previous iclog is in the
- * active or dirty state.
- *
- * We may sleep if:
- *
- * 1. the current iclog is not in the active nor dirty state.
- * 2. the current iclog dirty, and the previous iclog is not in the
- * active nor dirty state.
- * 3. the current iclog is active, and there is another thread writing
- * to this particular iclog.
- * 4. a) the current iclog is active and has no other writers
- * b) when we return from flushing out this iclog, it is still
- * not in the active nor dirty state.
- */
- int
- xfs_log_force(
- struct xfs_mount *mp,
- uint flags)
- {
- struct xlog *log = mp->m_log;
- struct xlog_in_core *iclog;
- xfs_lsn_t lsn;
- XFS_STATS_INC(mp, xs_log_force);
- trace_xfs_log_force(mp, 0, _RET_IP_);
- xlog_cil_force(log);
- spin_lock(&log->l_icloglock);
- iclog = log->l_iclog;
- if (iclog->ic_state == XLOG_STATE_IOERROR)
- goto out_error;
- if (iclog->ic_state == XLOG_STATE_DIRTY ||
- (iclog->ic_state == XLOG_STATE_ACTIVE &&
- atomic_read(&iclog->ic_refcnt) == 0 && iclog->ic_offset == 0)) {
- /*
- * If the head is dirty or (active and empty), then we need to
- * look at the previous iclog.
- *
- * If the previous iclog is active or dirty we are done. There
- * is nothing to sync out. Otherwise, we attach ourselves to the
- * previous iclog and go to sleep.
- */
- iclog = iclog->ic_prev;
- } else if (iclog->ic_state == XLOG_STATE_ACTIVE) {
- if (atomic_read(&iclog->ic_refcnt) == 0) {
- /*
- * We are the only one with access to this iclog.
- *
- * Flush it out now. There should be a roundoff of zero
- * to show that someone has already taken care of the
- * roundoff from the previous sync.
- */
- atomic_inc(&iclog->ic_refcnt);
- lsn = be64_to_cpu(iclog->ic_header.h_lsn);
- xlog_state_switch_iclogs(log, iclog, 0);
- if (xlog_state_release_iclog(log, iclog))
- goto out_error;
- if (be64_to_cpu(iclog->ic_header.h_lsn) != lsn)
- goto out_unlock;
- } else {
- /*
- * Someone else is writing to this iclog.
- *
- * Use its call to flush out the data. However, the
- * other thread may not force out this LR, so we mark
- * it WANT_SYNC.
- */
- xlog_state_switch_iclogs(log, iclog, 0);
- }
- } else {
- /*
- * If the head iclog is not active nor dirty, we just attach
- * ourselves to the head and go to sleep if necessary.
- */
- ;
- }
- if (flags & XFS_LOG_SYNC)
- return xlog_wait_on_iclog(iclog);
- out_unlock:
- spin_unlock(&log->l_icloglock);
- return 0;
- out_error:
- spin_unlock(&log->l_icloglock);
- return -EIO;
- }
- static int
- __xfs_log_force_lsn(
- struct xfs_mount *mp,
- xfs_lsn_t lsn,
- uint flags,
- int *log_flushed,
- bool already_slept)
- {
- struct xlog *log = mp->m_log;
- struct xlog_in_core *iclog;
- spin_lock(&log->l_icloglock);
- iclog = log->l_iclog;
- if (iclog->ic_state == XLOG_STATE_IOERROR)
- goto out_error;
- while (be64_to_cpu(iclog->ic_header.h_lsn) != lsn) {
- iclog = iclog->ic_next;
- if (iclog == log->l_iclog)
- goto out_unlock;
- }
- if (iclog->ic_state == XLOG_STATE_ACTIVE) {
- /*
- * We sleep here if we haven't already slept (e.g. this is the
- * first time we've looked at the correct iclog buf) and the
- * buffer before us is going to be sync'ed. The reason for this
- * is that if we are doing sync transactions here, by waiting
- * for the previous I/O to complete, we can allow a few more
- * transactions into this iclog before we close it down.
- *
- * Otherwise, we mark the buffer WANT_SYNC, and bump up the
- * refcnt so we can release the log (which drops the ref count).
- * The state switch keeps new transaction commits from using
- * this buffer. When the current commits finish writing into
- * the buffer, the refcount will drop to zero and the buffer
- * will go out then.
- */
- if (!already_slept &&
- (iclog->ic_prev->ic_state == XLOG_STATE_WANT_SYNC ||
- iclog->ic_prev->ic_state == XLOG_STATE_SYNCING)) {
- XFS_STATS_INC(mp, xs_log_force_sleep);
- xlog_wait(&iclog->ic_prev->ic_write_wait,
- &log->l_icloglock);
- return -EAGAIN;
- }
- atomic_inc(&iclog->ic_refcnt);
- xlog_state_switch_iclogs(log, iclog, 0);
- if (xlog_state_release_iclog(log, iclog))
- goto out_error;
- if (log_flushed)
- *log_flushed = 1;
- }
- if (flags & XFS_LOG_SYNC)
- return xlog_wait_on_iclog(iclog);
- out_unlock:
- spin_unlock(&log->l_icloglock);
- return 0;
- out_error:
- spin_unlock(&log->l_icloglock);
- return -EIO;
- }
- /*
- * Force the in-core log to disk for a specific LSN.
- *
- * Find in-core log with lsn.
- * If it is in the DIRTY state, just return.
- * If it is in the ACTIVE state, move the in-core log into the WANT_SYNC
- * state and go to sleep or return.
- * If it is in any other state, go to sleep or return.
- *
- * Synchronous forces are implemented with a wait queue. All callers trying
- * to force a given lsn to disk must wait on the queue attached to the
- * specific in-core log. When given in-core log finally completes its write
- * to disk, that thread will wake up all threads waiting on the queue.
- */
- int
- xfs_log_force_lsn(
- struct xfs_mount *mp,
- xfs_lsn_t lsn,
- uint flags,
- int *log_flushed)
- {
- int ret;
- ASSERT(lsn != 0);
- XFS_STATS_INC(mp, xs_log_force);
- trace_xfs_log_force(mp, lsn, _RET_IP_);
- lsn = xlog_cil_force_lsn(mp->m_log, lsn);
- if (lsn == NULLCOMMITLSN)
- return 0;
- ret = __xfs_log_force_lsn(mp, lsn, flags, log_flushed, false);
- if (ret == -EAGAIN)
- ret = __xfs_log_force_lsn(mp, lsn, flags, log_flushed, true);
- return ret;
- }
- /*
- * Free a used ticket when its refcount falls to zero.
- */
- void
- xfs_log_ticket_put(
- xlog_ticket_t *ticket)
- {
- ASSERT(atomic_read(&ticket->t_ref) > 0);
- if (atomic_dec_and_test(&ticket->t_ref))
- kmem_cache_free(xfs_log_ticket_zone, ticket);
- }
- xlog_ticket_t *
- xfs_log_ticket_get(
- xlog_ticket_t *ticket)
- {
- ASSERT(atomic_read(&ticket->t_ref) > 0);
- atomic_inc(&ticket->t_ref);
- return ticket;
- }
- /*
- * Figure out the total log space unit (in bytes) that would be
- * required for a log ticket.
- */
- int
- xfs_log_calc_unit_res(
- struct xfs_mount *mp,
- int unit_bytes)
- {
- struct xlog *log = mp->m_log;
- int iclog_space;
- uint num_headers;
- /*
- * Permanent reservations have up to 'cnt'-1 active log operations
- * in the log. A unit in this case is the amount of space for one
- * of these log operations. Normal reservations have a cnt of 1
- * and their unit amount is the total amount of space required.
- *
- * The following lines of code account for non-transaction data
- * which occupy space in the on-disk log.
- *
- * Normal form of a transaction is:
- * <oph><trans-hdr><start-oph><reg1-oph><reg1><reg2-oph>...<commit-oph>
- * and then there are LR hdrs, split-recs and roundoff at end of syncs.
- *
- * We need to account for all the leadup data and trailer data
- * around the transaction data.
- * And then we need to account for the worst case in terms of using
- * more space.
- * The worst case will happen if:
- * - the placement of the transaction happens to be such that the
- * roundoff is at its maximum
- * - the transaction data is synced before the commit record is synced
- * i.e. <transaction-data><roundoff> | <commit-rec><roundoff>
- * Therefore the commit record is in its own Log Record.
- * This can happen as the commit record is called with its
- * own region to xlog_write().
- * This then means that in the worst case, roundoff can happen for
- * the commit-rec as well.
- * The commit-rec is smaller than padding in this scenario and so it is
- * not added separately.
- */
- /* for trans header */
- unit_bytes += sizeof(xlog_op_header_t);
- unit_bytes += sizeof(xfs_trans_header_t);
- /* for start-rec */
- unit_bytes += sizeof(xlog_op_header_t);
- /*
- * for LR headers - the space for data in an iclog is the size minus
- * the space used for the headers. If we use the iclog size, then we
- * undercalculate the number of headers required.
- *
- * Furthermore - the addition of op headers for split-recs might
- * increase the space required enough to require more log and op
- * headers, so take that into account too.
- *
- * IMPORTANT: This reservation makes the assumption that if this
- * transaction is the first in an iclog and hence has the LR headers
- * accounted to it, then the remaining space in the iclog is
- * exclusively for this transaction. i.e. if the transaction is larger
- * than the iclog, it will be the only thing in that iclog.
- * Fundamentally, this means we must pass the entire log vector to
- * xlog_write to guarantee this.
- */
- iclog_space = log->l_iclog_size - log->l_iclog_hsize;
- num_headers = howmany(unit_bytes, iclog_space);
- /* for split-recs - ophdrs added when data split over LRs */
- unit_bytes += sizeof(xlog_op_header_t) * num_headers;
- /* add extra header reservations if we overrun */
- while (!num_headers ||
- howmany(unit_bytes, iclog_space) > num_headers) {
- unit_bytes += sizeof(xlog_op_header_t);
- num_headers++;
- }
- unit_bytes += log->l_iclog_hsize * num_headers;
- /* for commit-rec LR header - note: padding will subsume the ophdr */
- unit_bytes += log->l_iclog_hsize;
- /* for roundoff padding for transaction data and one for commit record */
- if (xfs_sb_version_haslogv2(&mp->m_sb) && mp->m_sb.sb_logsunit > 1) {
- /* log su roundoff */
- unit_bytes += 2 * mp->m_sb.sb_logsunit;
- } else {
- /* BB roundoff */
- unit_bytes += 2 * BBSIZE;
- }
- return unit_bytes;
- }
- /*
- * Allocate and initialise a new log ticket.
- */
- struct xlog_ticket *
- xlog_ticket_alloc(
- struct xlog *log,
- int unit_bytes,
- int cnt,
- char client,
- bool permanent)
- {
- struct xlog_ticket *tic;
- int unit_res;
- tic = kmem_cache_zalloc(xfs_log_ticket_zone, GFP_NOFS | __GFP_NOFAIL);
- unit_res = xfs_log_calc_unit_res(log->l_mp, unit_bytes);
- atomic_set(&tic->t_ref, 1);
- tic->t_task = current;
- INIT_LIST_HEAD(&tic->t_queue);
- tic->t_unit_res = unit_res;
- tic->t_curr_res = unit_res;
- tic->t_cnt = cnt;
- tic->t_ocnt = cnt;
- tic->t_tid = prandom_u32();
- tic->t_clientid = client;
- if (permanent)
- tic->t_flags |= XLOG_TIC_PERM_RESERV;
- xlog_tic_reset_res(tic);
- return tic;
- }
- #if defined(DEBUG)
- /*
- * Make sure that the destination ptr is within the valid data region of
- * one of the iclogs. This uses backup pointers stored in a different
- * part of the log in case we trash the log structure.
- */
- STATIC void
- xlog_verify_dest_ptr(
- struct xlog *log,
- void *ptr)
- {
- int i;
- int good_ptr = 0;
- for (i = 0; i < log->l_iclog_bufs; i++) {
- if (ptr >= log->l_iclog_bak[i] &&
- ptr <= log->l_iclog_bak[i] + log->l_iclog_size)
- good_ptr++;
- }
- if (!good_ptr)
- xfs_emerg(log->l_mp, "%s: invalid ptr", __func__);
- }
- /*
- * Check to make sure the grant write head didn't just over lap the tail. If
- * the cycles are the same, we can't be overlapping. Otherwise, make sure that
- * the cycles differ by exactly one and check the byte count.
- *
- * This check is run unlocked, so can give false positives. Rather than assert
- * on failures, use a warn-once flag and a panic tag to allow the admin to
- * determine if they want to panic the machine when such an error occurs. For
- * debug kernels this will have the same effect as using an assert but, unlinke
- * an assert, it can be turned off at runtime.
- */
- STATIC void
- xlog_verify_grant_tail(
- struct xlog *log)
- {
- int tail_cycle, tail_blocks;
- int cycle, space;
- xlog_crack_grant_head(&log->l_write_head.grant, &cycle, &space);
- xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_blocks);
- if (tail_cycle != cycle) {
- if (cycle - 1 != tail_cycle &&
- !(log->l_flags & XLOG_TAIL_WARN)) {
- xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES,
- "%s: cycle - 1 != tail_cycle", __func__);
- log->l_flags |= XLOG_TAIL_WARN;
- }
- if (space > BBTOB(tail_blocks) &&
- !(log->l_flags & XLOG_TAIL_WARN)) {
- xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES,
- "%s: space > BBTOB(tail_blocks)", __func__);
- log->l_flags |= XLOG_TAIL_WARN;
- }
- }
- }
- /* check if it will fit */
- STATIC void
- xlog_verify_tail_lsn(
- struct xlog *log,
- struct xlog_in_core *iclog,
- xfs_lsn_t tail_lsn)
- {
- int blocks;
- if (CYCLE_LSN(tail_lsn) == log->l_prev_cycle) {
- blocks =
- log->l_logBBsize - (log->l_prev_block - BLOCK_LSN(tail_lsn));
- if (blocks < BTOBB(iclog->ic_offset)+BTOBB(log->l_iclog_hsize))
- xfs_emerg(log->l_mp, "%s: ran out of log space", __func__);
- } else {
- ASSERT(CYCLE_LSN(tail_lsn)+1 == log->l_prev_cycle);
- if (BLOCK_LSN(tail_lsn) == log->l_prev_block)
- xfs_emerg(log->l_mp, "%s: tail wrapped", __func__);
- blocks = BLOCK_LSN(tail_lsn) - log->l_prev_block;
- if (blocks < BTOBB(iclog->ic_offset) + 1)
- xfs_emerg(log->l_mp, "%s: ran out of log space", __func__);
- }
- }
- /*
- * Perform a number of checks on the iclog before writing to disk.
- *
- * 1. Make sure the iclogs are still circular
- * 2. Make sure we have a good magic number
- * 3. Make sure we don't have magic numbers in the data
- * 4. Check fields of each log operation header for:
- * A. Valid client identifier
- * B. tid ptr value falls in valid ptr space (user space code)
- * C. Length in log record header is correct according to the
- * individual operation headers within record.
- * 5. When a bwrite will occur within 5 blocks of the front of the physical
- * log, check the preceding blocks of the physical log to make sure all
- * the cycle numbers agree with the current cycle number.
- */
- STATIC void
- xlog_verify_iclog(
- struct xlog *log,
- struct xlog_in_core *iclog,
- int count)
- {
- xlog_op_header_t *ophead;
- xlog_in_core_t *icptr;
- xlog_in_core_2_t *xhdr;
- void *base_ptr, *ptr, *p;
- ptrdiff_t field_offset;
- uint8_t clientid;
- int len, i, j, k, op_len;
- int idx;
- /* check validity of iclog pointers */
- spin_lock(&log->l_icloglock);
- icptr = log->l_iclog;
- for (i = 0; i < log->l_iclog_bufs; i++, icptr = icptr->ic_next)
- ASSERT(icptr);
- if (icptr != log->l_iclog)
- xfs_emerg(log->l_mp, "%s: corrupt iclog ring", __func__);
- spin_unlock(&log->l_icloglock);
- /* check log magic numbers */
- if (iclog->ic_header.h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
- xfs_emerg(log->l_mp, "%s: invalid magic num", __func__);
- base_ptr = ptr = &iclog->ic_header;
- p = &iclog->ic_header;
- for (ptr += BBSIZE; ptr < base_ptr + count; ptr += BBSIZE) {
- if (*(__be32 *)ptr == cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
- xfs_emerg(log->l_mp, "%s: unexpected magic num",
- __func__);
- }
- /* check fields */
- len = be32_to_cpu(iclog->ic_header.h_num_logops);
- base_ptr = ptr = iclog->ic_datap;
- ophead = ptr;
- xhdr = iclog->ic_data;
- for (i = 0; i < len; i++) {
- ophead = ptr;
- /* clientid is only 1 byte */
- p = &ophead->oh_clientid;
- field_offset = p - base_ptr;
- if (field_offset & 0x1ff) {
- clientid = ophead->oh_clientid;
- } else {
- idx = BTOBBT((char *)&ophead->oh_clientid - iclog->ic_datap);
- if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) {
- j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
- k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
- clientid = xlog_get_client_id(
- xhdr[j].hic_xheader.xh_cycle_data[k]);
- } else {
- clientid = xlog_get_client_id(
- iclog->ic_header.h_cycle_data[idx]);
- }
- }
- if (clientid != XFS_TRANSACTION && clientid != XFS_LOG)
- xfs_warn(log->l_mp,
- "%s: invalid clientid %d op "PTR_FMT" offset 0x%lx",
- __func__, clientid, ophead,
- (unsigned long)field_offset);
- /* check length */
- p = &ophead->oh_len;
- field_offset = p - base_ptr;
- if (field_offset & 0x1ff) {
- op_len = be32_to_cpu(ophead->oh_len);
- } else {
- idx = BTOBBT((uintptr_t)&ophead->oh_len -
- (uintptr_t)iclog->ic_datap);
- if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) {
- j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
- k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
- op_len = be32_to_cpu(xhdr[j].hic_xheader.xh_cycle_data[k]);
- } else {
- op_len = be32_to_cpu(iclog->ic_header.h_cycle_data[idx]);
- }
- }
- ptr += sizeof(xlog_op_header_t) + op_len;
- }
- }
- #endif
- /*
- * Mark all iclogs IOERROR. l_icloglock is held by the caller.
- */
- STATIC int
- xlog_state_ioerror(
- struct xlog *log)
- {
- xlog_in_core_t *iclog, *ic;
- iclog = log->l_iclog;
- if (iclog->ic_state != XLOG_STATE_IOERROR) {
- /*
- * Mark all the incore logs IOERROR.
- * From now on, no log flushes will result.
- */
- ic = iclog;
- do {
- ic->ic_state = XLOG_STATE_IOERROR;
- ic = ic->ic_next;
- } while (ic != iclog);
- return 0;
- }
- /*
- * Return non-zero, if state transition has already happened.
- */
- return 1;
- }
- /*
- * This is called from xfs_force_shutdown, when we're forcibly
- * shutting down the filesystem, typically because of an IO error.
- * Our main objectives here are to make sure that:
- * a. if !logerror, flush the logs to disk. Anything modified
- * after this is ignored.
- * b. the filesystem gets marked 'SHUTDOWN' for all interested
- * parties to find out, 'atomically'.
- * c. those who're sleeping on log reservations, pinned objects and
- * other resources get woken up, and be told the bad news.
- * d. nothing new gets queued up after (b) and (c) are done.
- *
- * Note: for the !logerror case we need to flush the regions held in memory out
- * to disk first. This needs to be done before the log is marked as shutdown,
- * otherwise the iclog writes will fail.
- */
- int
- xfs_log_force_umount(
- struct xfs_mount *mp,
- int logerror)
- {
- struct xlog *log;
- int retval;
- log = mp->m_log;
- /*
- * If this happens during log recovery, don't worry about
- * locking; the log isn't open for business yet.
- */
- if (!log ||
- log->l_flags & XLOG_ACTIVE_RECOVERY) {
- mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN;
- if (mp->m_sb_bp)
- mp->m_sb_bp->b_flags |= XBF_DONE;
- return 0;
- }
- /*
- * Somebody could've already done the hard work for us.
- * No need to get locks for this.
- */
- if (logerror && log->l_iclog->ic_state == XLOG_STATE_IOERROR) {
- ASSERT(XLOG_FORCED_SHUTDOWN(log));
- return 1;
- }
- /*
- * Flush all the completed transactions to disk before marking the log
- * being shut down. We need to do it in this order to ensure that
- * completed operations are safely on disk before we shut down, and that
- * we don't have to issue any buffer IO after the shutdown flags are set
- * to guarantee this.
- */
- if (!logerror)
- xfs_log_force(mp, XFS_LOG_SYNC);
- /*
- * mark the filesystem and the as in a shutdown state and wake
- * everybody up to tell them the bad news.
- */
- spin_lock(&log->l_icloglock);
- mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN;
- if (mp->m_sb_bp)
- mp->m_sb_bp->b_flags |= XBF_DONE;
- /*
- * Mark the log and the iclogs with IO error flags to prevent any
- * further log IO from being issued or completed.
- */
- log->l_flags |= XLOG_IO_ERROR;
- retval = xlog_state_ioerror(log);
- spin_unlock(&log->l_icloglock);
- /*
- * We don't want anybody waiting for log reservations after this. That
- * means we have to wake up everybody queued up on reserveq as well as
- * writeq. In addition, we make sure in xlog_{re}grant_log_space that
- * we don't enqueue anything once the SHUTDOWN flag is set, and this
- * action is protected by the grant locks.
- */
- xlog_grant_head_wake_all(&log->l_reserve_head);
- xlog_grant_head_wake_all(&log->l_write_head);
- /*
- * Wake up everybody waiting on xfs_log_force. Wake the CIL push first
- * as if the log writes were completed. The abort handling in the log
- * item committed callback functions will do this again under lock to
- * avoid races.
- */
- spin_lock(&log->l_cilp->xc_push_lock);
- wake_up_all(&log->l_cilp->xc_commit_wait);
- spin_unlock(&log->l_cilp->xc_push_lock);
- xlog_state_do_callback(log);
- /* return non-zero if log IOERROR transition had already happened */
- return retval;
- }
- STATIC int
- xlog_iclogs_empty(
- struct xlog *log)
- {
- xlog_in_core_t *iclog;
- iclog = log->l_iclog;
- do {
- /* endianness does not matter here, zero is zero in
- * any language.
- */
- if (iclog->ic_header.h_num_logops)
- return 0;
- iclog = iclog->ic_next;
- } while (iclog != log->l_iclog);
- return 1;
- }
- /*
- * Verify that an LSN stamped into a piece of metadata is valid. This is
- * intended for use in read verifiers on v5 superblocks.
- */
- bool
- xfs_log_check_lsn(
- struct xfs_mount *mp,
- xfs_lsn_t lsn)
- {
- struct xlog *log = mp->m_log;
- bool valid;
- /*
- * norecovery mode skips mount-time log processing and unconditionally
- * resets the in-core LSN. We can't validate in this mode, but
- * modifications are not allowed anyways so just return true.
- */
- if (mp->m_flags & XFS_MOUNT_NORECOVERY)
- return true;
- /*
- * Some metadata LSNs are initialized to NULL (e.g., the agfl). This is
- * handled by recovery and thus safe to ignore here.
- */
- if (lsn == NULLCOMMITLSN)
- return true;
- valid = xlog_valid_lsn(mp->m_log, lsn);
- /* warn the user about what's gone wrong before verifier failure */
- if (!valid) {
- spin_lock(&log->l_icloglock);
- xfs_warn(mp,
- "Corruption warning: Metadata has LSN (%d:%d) ahead of current LSN (%d:%d). "
- "Please unmount and run xfs_repair (>= v4.3) to resolve.",
- CYCLE_LSN(lsn), BLOCK_LSN(lsn),
- log->l_curr_cycle, log->l_curr_block);
- spin_unlock(&log->l_icloglock);
- }
- return valid;
- }
- bool
- xfs_log_in_recovery(
- struct xfs_mount *mp)
- {
- struct xlog *log = mp->m_log;
- return log->l_flags & XLOG_ACTIVE_RECOVERY;
- }
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