From 8785440f5255258b3c6df338f8b8605080662896 Mon Sep 17 00:00:00 2001
From: Simon Graham <sgraham@anna.sn.stratus.com>
Date: Sat, 22 Dec 2007 13:17:14 -0500
Subject: [PATCH] Add split-brain event to netlink

---
 drbd/drbd_int.h      |    1 +
 drbd/drbd_nl.c       |   35 +++++++++++++++++++++++++++++++++++
 drbd/drbd_receiver.c |    1 +
 drbd/linux/drbd_nl.h |    4 ++++
 user/drbdsetup.c     |    8 ++++++++
 5 files changed, 49 insertions(+), 0 deletions(-)

diff --git a/drbd/drbd_int.h b/drbd/drbd_int.h
index 01eeba6..b374dc7 100644
--- a/drbd/drbd_int.h
+++ b/drbd/drbd_int.h
@@ -1426,6 +1426,7 @@ void drbd_nl_cleanup(void);
 int __init drbd_nl_init(void);
 void drbd_bcast_state(drbd_dev *mdev, drbd_state_t state);
 void drbd_bcast_sync_progress(drbd_dev *mdev);
+void drbd_bcast_split_brain(drbd_dev *mdev,int flag);
 
 /*
  * inline helper functions
diff --git a/drbd/drbd_nl.c b/drbd/drbd_nl.c
index 61593ed..5ef1d89 100644
--- a/drbd/drbd_nl.c
+++ b/drbd/drbd_nl.c
@@ -1769,6 +1769,41 @@ void drbd_bcast_ev_helper(drbd_dev *mdev, char* helper_name)
 	cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_KERNEL);
 }
 
+void drbd_bcast_split_brain(drbd_dev *mdev,int flag)
+{
+	char buffer[sizeof(struct cn_msg)+
+		    sizeof(struct drbd_nl_cfg_reply)+
+		    sizeof(struct split_brain_tag_len_struct)+
+		    sizeof(short int)];
+	struct cn_msg *cn_reply = (struct cn_msg *) buffer;
+	struct drbd_nl_cfg_reply* reply = (struct drbd_nl_cfg_reply*)cn_reply->data;
+	unsigned short *tl = reply->tag_list;
+	int val = flag;
+       
+	*tl++ = T_split_brain;
+	*tl++ = sizeof(int);
+       memcpy(tl, &val, sizeof(int));
+	tl=(unsigned short*)((char*)tl + sizeof(int));
+	*tl++ = TT_END; /* Close the tag list */
+
+	cn_reply->id.idx = CN_IDX_DRBD;
+	cn_reply->id.val = CN_VAL_DRBD;
+
+	cn_reply->seq = atomic_add_return(1,&drbd_nl_seq);
+	cn_reply->ack = 0; // not used here.
+	cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
+		(int)((char*)tl - (char*)reply->tag_list);
+	cn_reply->flags = 0;
+
+	reply->packet_type = P_split_brain;
+	reply->minor = mdev_to_minor(mdev);
+	reply->ret_code = NoError;
+
+	TRACE(TraceTypeNl, TraceLvlSummary, nl_trace_reply(cn_reply););
+
+	cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_KERNEL);
+}
+
 void drbd_bcast_sync_progress(drbd_dev *mdev)
 {
 	char buffer[sizeof(struct cn_msg)+
diff --git a/drbd/drbd_receiver.c b/drbd/drbd_receiver.c
index 08ade49..a89921c 100644
--- a/drbd/drbd_receiver.c
+++ b/drbd/drbd_receiver.c
@@ -2023,6 +2023,7 @@ STATIC drbd_conns_t drbd_sync_handshake(drbd_dev *mdev, drbd_role_t peer_role,
 		drbd_uuid_dump(mdev,"self",mdev->bc->md.uuid);
 		drbd_uuid_dump(mdev,"peer",mdev->p_uuid);
 		drbd_force_state(mdev,NS(conn,Disconnecting));
+		drbd_bcast_split_brain(mdev,1);//Tell user we split brained 
 		drbd_khelper(mdev,"split-brain");
 		return conn_mask;
 	}
diff --git a/drbd/linux/drbd_nl.h b/drbd/linux/drbd_nl.h
index b0e770c..8c6168f 100644
--- a/drbd/linux/drbd_nl.h
+++ b/drbd/linux/drbd_nl.h
@@ -97,6 +97,10 @@ NL_PACKET(sync_progress, 23,
 	NL_INTEGER(	43,	T_MAY_IGNORE,	sync_progress)
 )
 
+NL_PACKET(split_brain, 24,
+	NL_INTEGER(	44,	T_MAY_IGNORE,	split_brain)
+)
+
 #undef NL_PACKET
 #undef NL_INTEGER
 #undef NL_INT64
diff --git a/user/drbdsetup.c b/user/drbdsetup.c
index 0f5ddc2..d088cd8 100644
--- a/user/drbdsetup.c
+++ b/user/drbdsetup.c
@@ -1238,6 +1238,14 @@ int print_state(unsigned int seq, int u __attribute((unused)),
 				synced % 10);
 		} else fprintf(stderr,"Missing tag !?\n");
 		break;
+	case P_split_brain:
+		if (consume_tag_int(T_split_brain, reply->tag_list, &synced)) {
+			printf("%u SB %d %d\n", 
+				seq,
+				reply->minor,
+				synced);
+		} else fprintf(stderr,"Missing tag !?\n");
+		break;
 	default:
 		printf("%u ?? %d <other message>\n",seq, reply->minor);
 		break;
-- 
1.5.4.rc1