Before this patch, journal replays could stomp on log flushes and each other because both log flushes and journal replays used the same sd_log_bio. Function gfs2_log_flush prevents other log flushes from interfering by taking the sd_log_flush_lock rwsem during the flush. However, it does not protect against journal replays. This patch allows the journal replay to take the same sd_log_flush_lock rwsem so use of the sd_log_bio is not stomped.
Signed-off-by: Bob Peterson <[email protected]> --- fs/gfs2/recovery.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c index 8cc26bef4e64..21fc44b31863 100644 --- a/fs/gfs2/recovery.c +++ b/fs/gfs2/recovery.c @@ -398,6 +398,10 @@ void gfs2_recover_func(struct work_struct *work) fs_info(sdp, "jid=%u: Replaying journal...0x%x to 0x%x\n", jd->jd_jid, head.lh_tail, head.lh_blkno); + /* We take the sd_log_flush_lock here primarily to prevent log + * flushes and simultaneous journal replays from stomping on + * each other wrt sd_log_bio. */ + down_write(&sdp->sd_log_flush_lock); for (pass = 0; pass < 2; pass++) { lops_before_scan(jd, &head, pass); error = foreach_descriptor(jd, head.lh_tail, @@ -408,6 +412,7 @@ void gfs2_recover_func(struct work_struct *work) } clean_journal(jd, &head); + up_write(&sdp->sd_log_flush_lock); gfs2_glock_dq_uninit(&thaw_gh); t_rep = ktime_get(); -- 2.24.1
