ocfs2: NFS hangs in __ocfs2_cluster_lock due to race with ocfs2_unblock_lock

[mirror_ubuntu-artful-kernel.git] / fs / ocfs2 / dlmglue.c

diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index f92612e4b9d61144b13021c83dd8b4b1e9553ac5..474e57f834e6caff12eaca03c8ece4d35303d1e0 100644 (file)
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -1390,6 +1390,7 @@ static int __ocfs2_cluster_lock(struct ocfs2_super *osb,
        unsigned int gen;
        int noqueue_attempted = 0;
        int dlm_locked = 0;
+       int kick_dc = 0;
 
        if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED)) {
                mlog_errno(-EINVAL);
@@ -1524,7 +1525,12 @@ update_holders:
 unlock:
        lockres_clear_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING);
 
+       /* ocfs2_unblock_lock reques on seeing OCFS2_LOCK_UPCONVERT_FINISHING */
+       kick_dc = (lockres->l_flags & OCFS2_LOCK_BLOCKED);
+
        spin_unlock_irqrestore(&lockres->l_lock, flags);
+       if (kick_dc)
+               ocfs2_wake_downconvert_thread(osb);
 out:
        /*
         * This is helping work around a lock inversion between the page lock