From 8341339ec44def87121360aa81bff2d8f8227e43 Mon Sep 17 00:00:00 2001
From: Dexuan Cui <decui@microsoft.com>
Date: Mon, 14 Dec 2015 16:01:50 -0800
Subject: [PATCH 20/44] Drivers: hv: vmbus: release relid on error in
 vmbus_process_offer()

We want to simplify vmbus_onoffer_rescind() by not invoking
hv_process_channel_removal(NULL, ...).

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit f52078cf5711ce47c113a58702b35c8ff5f212f5)
---
 drivers/hv/channel_mgmt.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 9b4525c56376..8529dd2ebc3d 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -178,19 +178,22 @@ static void percpu_channel_deq(void *arg)
 }
 
 
-void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
+static void vmbus_release_relid(u32 relid)
 {
 	struct vmbus_channel_relid_released msg;
-	unsigned long flags;
-	struct vmbus_channel *primary_channel;
 
 	memset(&msg, 0, sizeof(struct vmbus_channel_relid_released));
 	msg.child_relid = relid;
 	msg.header.msgtype = CHANNELMSG_RELID_RELEASED;
 	vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released));
+}
 
-	if (channel == NULL)
-		return;
+void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
+{
+	unsigned long flags;
+	struct vmbus_channel *primary_channel;
+
+	vmbus_release_relid(relid);
 
 	BUG_ON(!channel->rescind);
 
@@ -337,6 +340,8 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 	return;
 
 err_deq_chan:
+	vmbus_release_relid(newchannel->offermsg.child_relid);
+
 	spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 	list_del(&newchannel->listentry);
 	spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
@@ -640,7 +645,11 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 	channel = relid2channel(rescind->child_relid);
 
 	if (channel == NULL) {
-		hv_process_channel_removal(NULL, rescind->child_relid);
+		/*
+		 * This is very impossible, because in
+		 * vmbus_process_offer(), we have already invoked
+		 * vmbus_release_relid() on error.
+		 */
 		return;
 	}
 
-- 
2.13.0

