ocfs2: Move o2hb functionality into the stack glue.

The last bit of classic stack used directly in ocfs2 code is o2hb.
Specifically, the check for heartbeat during mount and the call to
ocfs2_hb_ctl during unmount.

We create an extra API, ocfs2_cluster_hangup(), to encapsulate the call
to ocfs2_hb_ctl.  Other stacks will just leave hangup() empty.

The check for heartbeat is moved into ocfs2_cluster_connect().  It will
be matched by a similar check for other stacks.

With this change, only stackglue.c includes cluster/ headers.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

1 files changed, 50 insertions, 0 deletions

diff --git a/fs/ocfs2/stackglue.c b/fs/ocfs2/stackglue.c
index 814686356cc6..670fa945c212 100644
--- a/fs/ocfs2/stackglue.c
+++ b/fs/ocfs2/stackglue.c
@@ -20,12 +20,14 @@
 
 #include <linux/slab.h>
 #include <linux/crc32.h>
+#include <linux/kmod.h>
 
 /* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */
 #include <linux/fs.h>
 
 #include "cluster/masklog.h"
 #include "cluster/nodemanager.h"
+#include "cluster/heartbeat.h"
 
 #include "stackglue.h"
 
@@ -301,6 +303,13 @@ int ocfs2_cluster_connect(const char *group,
 		goto out;
 	}
 
+	/* for now we only have one cluster/node, make sure we see it
+	 * in the heartbeat universe */
+	if (!o2hb_check_local_node_heartbeating()) {
+		rc = -EINVAL;
+		goto out;
+	}
+
 	new_conn = kzalloc(sizeof(struct ocfs2_cluster_connection),
 			   GFP_KERNEL);
 	if (!new_conn) {
@@ -359,6 +368,7 @@ out:
 	return rc;
 }
 
+
 int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn)
 {
 	struct dlm_ctxt *dlm = conn->cc_lockspace;
@@ -373,6 +383,46 @@ int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn)
 	return 0;
 }
 
+static void o2hb_stop(const char *group)
+{
+	int ret;
+	char *argv[5], *envp[3];
+
+	argv[0] = (char *)o2nm_get_hb_ctl_path();
+	argv[1] = "-K";
+	argv[2] = "-u";
+	argv[3] = (char *)group;
+	argv[4] = NULL;
+
+	mlog(0, "Run: %s %s %s %s\n", argv[0], argv[1], argv[2], argv[3]);
+
+	/* minimal command environment taken from cpu_run_sbin_hotplug */
+	envp[0] = "HOME=/";
+	envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
+	envp[2] = NULL;
+
+	ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
+	if (ret < 0)
+		mlog_errno(ret);
+}
+
+/*
+ * Hangup is a hack for tools compatibility.  Older ocfs2-tools software
+ * expects the filesystem to call "ocfs2_hb_ctl" during unmount.  This
+ * happens regardless of whether the DLM got started, so we can't do it
+ * in ocfs2_cluster_disconnect().  We bring the o2hb_stop() function into
+ * the glue and provide a "hangup" API for super.c to call.
+ *
+ * Other stacks will eventually provide a NULL ->hangup() pointer.
+ */
+void ocfs2_cluster_hangup(const char *group, int grouplen)
+{
+	BUG_ON(group == NULL);
+	BUG_ON(group[grouplen] != '\0');
+
+	o2hb_stop(group);
+}
+
 int ocfs2_cluster_this_node(unsigned int *node)
 {
 	int node_num;