[SCSI] mptsas: support basic hotplug

Adds hotplug support for SAS end devices.  Unfortunately the fusion
firmware doesn't generate similar events for expanders addition/removal
so we can't support them yet.  Eric has an idea about a clever scheme to
find out about expander changes so that'll be added later on.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/message/fusion/mptbase.h b/drivers/message/fusion/mptbase.h
index 6c48d1f54ac9..af9007d498ee 100644
--- a/drivers/message/fusion/mptbase.h
+++ b/drivers/message/fusion/mptbase.h
@@ -612,6 +612,7 @@ typedef struct _MPT_ADAPTER
         struct list_head         list;
         struct net_device       *netdev;
         struct list_head         sas_topology;
+        struct mutex             sas_topology_mutex;
         MPT_SAS_MGMT             sas_mgmt;
 } MPT_ADAPTER;