From: Dave Chinner <dchinner@xxxxxxxxxx>
We force iclogs in several places - we need them all to have the
same cache flush semantics, so start by factoring out the iclog
force into a common helper.
Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
fs/xfs/xfs_log.c | 42 ++++++++++++++++++------------------------
1 file changed, 18 insertions(+), 24 deletions(-)
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index e8c6c96d4f7c..184c68ea62bb 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -778,6 +778,20 @@ xfs_log_mount_cancel(
xfs_log_unmount(mp);
}
+/*
+ * Flush out the iclog to disk ensuring that device caches are flushed and
+ * the iclog hits stable storage before any completion waiters are woken.
+ */
+static inline int
+xlog_force_iclog(
+ struct xlog_in_core *iclog)
+{
+ atomic_inc(&iclog->ic_refcnt);
+ if (iclog->ic_state == XLOG_STATE_ACTIVE)
+ xlog_state_switch_iclogs(iclog->ic_log, iclog, 0);
+ return xlog_state_release_iclog(iclog->ic_log, iclog, 0);
+}
+
/*
* Wait for the iclog and all prior iclogs to be written disk as required by the
* log force state machine. Waiting on ic_force_wait ensures iclog completions
@@ -863,18 +877,8 @@ xlog_unmount_write(
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);
- /*
- * Ensure the journal is fully flushed and on stable storage once the
- * iclog containing the unmount record is written.
- */
iclog->ic_flags |= (XLOG_ICL_NEED_FLUSH | XLOG_ICL_NEED_FUA);
- error = xlog_state_release_iclog(log, iclog, 0);
+ error = xlog_force_iclog(iclog);
xlog_wait_on_iclog(iclog);
if (tic) {
@@ -3201,17 +3205,9 @@ xfs_log_force(
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);
+ /* We have exclusive access to this iclog. */
lsn = be64_to_cpu(iclog->ic_header.h_lsn);
- xlog_state_switch_iclogs(log, iclog, 0);
- if (xlog_state_release_iclog(log, iclog, 0))
+ if (xlog_force_iclog(iclog))
goto out_error;
if (be64_to_cpu(iclog->ic_header.h_lsn) != lsn)
@@ -3289,9 +3285,7 @@ xlog_force_lsn(
&log->l_icloglock);
return -EAGAIN;
}
- atomic_inc(&iclog->ic_refcnt);
- xlog_state_switch_iclogs(log, iclog, 0);
- if (xlog_state_release_iclog(log, iclog, 0))
+ if (xlog_force_iclog(iclog))
goto out_error;
if (log_flushed)
*log_flushed = 1;
--
2.31.1
