From: Martin Schwenke <martin@meltin.net>
Date: Tue, 8 Feb 2022 01:23:42 +0000 (+1100)
Subject: ctdb-mutex: Test the lock by locking a 2nd byte range
X-Git-Tag: samba-4.17.0rc1~247
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=061315cc795d8615fd94d4b23934ca1bf3aecebc;p=thirdparty%2Fsamba.git

ctdb-mutex: Test the lock by locking a 2nd byte range

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>
---

diff --git a/ctdb/server/ctdb_mutex_fcntl_helper.c b/ctdb/server/ctdb_mutex_fcntl_helper.c
index 07f111a0d6b..84d3790db57 100644
--- a/ctdb/server/ctdb_mutex_fcntl_helper.c
+++ b/ctdb/server/ctdb_mutex_fcntl_helper.c
@@ -265,6 +265,23 @@ static void lock_io_check_loop(struct tevent_req *subreq)
 		goto done;
 	}
 
+	/*
+	 * Attempt to lock a 2nd byte range.  Using a blocking lock
+	 * encourages ping timeouts if the cluster filesystem is in a
+	 * bad state.  It also makes testing easier.
+	 */
+	ret = fcntl_lock_fd(fd, true, 1);
+	if (ret != 0) {
+		fprintf(stderr,
+			"%s: "
+			"lock fail - lock file \"%s\" test lock error (%d)\n",
+			progname,
+			state->lock_file,
+			ret);
+		goto done;
+	}
+
+	/* Unlock occurs on close */
 	close(fd);
 
 	subreq = tevent_wakeup_send(