[Cluster-devel] [GFS2 PATCH] GFS2: Allow glocks to be unlocked after withdraw

Hi,

Before this patch, glocks could not be unlocked after a withdraw,
but that resulted in hangs during unmount. This patch allows GFS2
function do_xmote to demote locks to an unlocked state, but not
promoting any upward.

Signed-off-by: Bob Peterson <[email protected]>
---
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 9e81219..959a19c 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -449,7 +449,8 @@ __acquires(&gl->gl_lockref.lock)
 	unsigned int lck_flags = (unsigned int)(gh ? gh->gh_flags : 0);
 	int ret;
 
-	if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
+	if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) &&
+	    target != LM_ST_UNLOCKED)
 		return;
 	lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP |
 		      LM_FLAG_PRIORITY);
@@ -486,7 +487,8 @@ __acquires(&gl->gl_lockref.lock)
 		}
 		else if (ret) {
 			pr_err("lm_lock ret %d\n", ret);
-			GLOCK_BUG_ON(gl, 1);
+			GLOCK_BUG_ON(gl, !test_bit(SDF_SHUTDOWN,
+						   &sdp->sd_flags));
 		}
 	} else { /* lock_nolock */
 		finish_xmote(gl, target);