1 files changed, 28 insertions, 3 deletions

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 5afaf92057c0..6af1edabef05 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -622,6 +622,32 @@ __acquires(&gl->gl_lockref.lock)
 	}
 
 	gfs2_glock_hold(gl);
+	/*
+	 * Check for an error encountered since we called go_sync and go_inval.
+	 * If so, we can't withdraw from the glock code because the withdraw
+	 * code itself uses glocks (see function signal_our_withdraw) to
+	 * change the mount to read-only. Most importantly, we must not call
+	 * dlm to unlock the glock until the journal is in a known good state
+	 * (after journal replay) otherwise other nodes may use the object
+	 * (rgrp or dinode) and then later, journal replay will corrupt the
+	 * file system. The best we can do here is wait for the logd daemon
+	 * to see sd_log_error and withdraw, and in the meantime, requeue the
+	 * work for later.
+	 *
+	 * However, if we're just unlocking the lock (say, for unmount, when
+	 * gfs2_gl_hash_clear calls clear_glock) and recovery is complete
+	 * then it's okay to tell dlm to unlock it.
+	 */
+	if (unlikely(sdp->sd_log_error && !gfs2_withdrawn(sdp)))
+		gfs2_withdraw_delayed(sdp);
+	if (glock_blocked_by_withdraw(gl)) {
+		if (target != LM_ST_UNLOCKED ||
+		    test_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags)) {
+			gfs2_glock_queue_work(gl, GL_GLOCK_DFT_HOLD);
+			goto out;
+		}
+	}
+
 	if (sdp->sd_lockstruct.ls_ops->lm_lock)	{
 		/* lock_dlm */
 		ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags);
@@ -630,8 +656,7 @@ __acquires(&gl->gl_lockref.lock)
 		    test_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags)) {
 			finish_xmote(gl, target);
 			gfs2_glock_queue_work(gl, 0);
-		}
-		else if (ret) {
+		} else if (ret) {
 			fs_err(sdp, "lm_lock ret %d\n", ret);
 			GLOCK_BUG_ON(gl, !gfs2_withdrawn(sdp));
 		}
@@ -639,7 +664,7 @@ __acquires(&gl->gl_lockref.lock)
 		finish_xmote(gl, target);
 		gfs2_glock_queue_work(gl, 0);
 	}
-
+out:
 	spin_lock(&gl->gl_lockref.lock);
 }