From c5d85a071b33ac8a80ae8f6ddaf26f9fa7bc67a6 Mon Sep 17 00:00:00 2001
From: Martin Schwenke <martin@meltin.net>
Date: Tue, 21 Jun 2016 21:16:27 +1000
Subject: [PATCH] ctdb-ipalloc: New function ipalloc_can_host_ips()

Abstracts out code involving internals of IP allocation state.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>
---
 ctdb/server/ctdb_takeover.c | 12 ++----------
 ctdb/server/ipalloc.c       | 13 +++++++++++++
 ctdb/server/ipalloc.h       |  2 ++
 3 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/ctdb/server/ctdb_takeover.c b/ctdb/server/ctdb_takeover.c
index c45b218cc38..efa466a77a0 100644
--- a/ctdb/server/ctdb_takeover.c
+++ b/ctdb/server/ctdb_takeover.c
@@ -1543,7 +1543,7 @@ static void takeover_run_process_failures(struct ctdb_context *ctdb,
  *   values can be faked in unit testing)
  * - Use ipalloc_set_public_ips() to set known and available IP
      addresses for allocation
- * - If no available IP addresses then early exit
+ * - If cluster can't host IP addresses then early exit
  * - Populate list of nodes to force rebalance - internal structure,
  *   currently no way to fetch, only used by LCP2 for nodes that have
  *   had new IP addresses added
@@ -1567,7 +1567,6 @@ int ctdb_takeover_run(struct ctdb_context *ctdb, struct ctdb_node_map_old *nodem
 	struct ipalloc_state *ipalloc_state;
 	struct ctdb_public_ip_list *known_ips, *available_ips;
 	struct takeover_callback_data *takeover_data;
-	bool can_host_ips;
 
 	/* Initialise fail callback data to be used with
 	 * takeover_run_fail_callback().  A failure in any of the
@@ -1624,14 +1623,7 @@ int ctdb_takeover_run(struct ctdb_context *ctdb, struct ctdb_node_map_old *nodem
 		return -1;
 	}
 
-	/* Short-circuit IP allocation if no node has available IPs */
-	can_host_ips = false;
-	for (i=0; i < ipalloc_state->num; i++) {
-		if (ipalloc_state->available_public_ips[i].num != 0) {
-			can_host_ips = true;
-		}
-	}
-	if (!can_host_ips) {
+	if (! ipalloc_can_host_ips(ipalloc_state)) {
 		DEBUG(DEBUG_WARNING,("No nodes available to host public IPs yet\n"));
 		goto ipreallocated;
 	}
diff --git a/ctdb/server/ipalloc.c b/ctdb/server/ipalloc.c
index 72e0fc4d34f..868ac841bcb 100644
--- a/ctdb/server/ipalloc.c
+++ b/ctdb/server/ipalloc.c
@@ -129,6 +129,19 @@ bool ipalloc_set_public_ips(struct ipalloc_state *ipalloc_state,
 	return (ipalloc_state->all_ips != NULL);
 }
 
+bool ipalloc_can_host_ips(struct ipalloc_state *ipalloc_state)
+{
+	int i;
+
+	for (i=0; i < ipalloc_state->num; i++) {
+		if (ipalloc_state->available_public_ips[i].num != 0) {
+			return true;
+		}
+	}
+
+	return false;
+}
+
 /* The calculation part of the IP allocation algorithm. */
 bool ipalloc(struct ipalloc_state *ipalloc_state)
 {
diff --git a/ctdb/server/ipalloc.h b/ctdb/server/ipalloc.h
index 06c69f87d0c..3d7d783d887 100644
--- a/ctdb/server/ipalloc.h
+++ b/ctdb/server/ipalloc.h
@@ -59,6 +59,8 @@ bool ipalloc_set_public_ips(struct ipalloc_state *ipalloc_state,
 			    struct ctdb_public_ip_list *known_ips,
 			    struct ctdb_public_ip_list *available_ips);
 
+bool ipalloc_can_host_ips(struct ipalloc_state *ipalloc_state);
+
 bool ipalloc(struct ipalloc_state *ipalloc_state);
 
 #endif /* __CTDB_IPALLOC_H__ */