[libvirt] [PATCH 1/2] storage: Check for valid fc_host parent at startup

[John Ferlan]

https://bugzilla.redhat.com/show_bug.cgi?id=1160565

If a 'parent' attribute is provided for the fchost, then at startup
time check to ensure it is a vport capable scsi_host. If the parent
is not vport capable, then disallow the startup. The following is the
expected results:

error: Failed to start pool fc_pool
error: XML error: parent 'scsi_host2' specified for vHBA is not vport capable

where the XML for the fc_pool is:

    <pool type='scsi'>
      <name>fc_pool</name>
      <source>
        <adapter type='fc_host' parent='scsi_host2' wwnn='5001a4aaf3ca174b' wwpn='5001a4a77192b864'/>
      </source>
...

and 'scsi_host2' is not vport capable.

Providing an incorrect parent and a correct wwnn/wwpn could lead to
failures at shutdown (deleteVport) where the assumption is the parent
is for the fchost.

NOTE: If the provided wwnn/wwpn doesn't resolve to an existing scsi_host,
      then we will be creating one with code (virManageVport) which
      assumes the parent is vport capable.

Signed-off-by: John Ferlan <jferlan at redhat.com>
---
 src/storage/storage_backend_scsi.c | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/src/storage/storage_backend_scsi.c b/src/storage/storage_backend_scsi.c
index 02160bc..549d8db 100644
--- a/src/storage/storage_backend_scsi.c
+++ b/src/storage/storage_backend_scsi.c
@@ -556,6 +556,20 @@ createVport(virStoragePoolSourceAdapter adapter)
     if (adapter.type != VIR_STORAGE_POOL_SOURCE_ADAPTER_TYPE_FC_HOST)
         return 0;
 
+    /* If a parent was provided, then let's make sure it's vhost capable */
+    if (adapter.data.fchost.parent) {
+        if (virGetSCSIHostNumber(adapter.data.fchost.parent, &parent_host) < 0)
+            return -1;
+
+        if (!virIsCapableFCHost(NULL, parent_host)) {
+            virReportError(VIR_ERR_XML_ERROR,
+                           _("parent '%s' specified for vHBA "
+                             "is not vport capable"),
+                           adapter.data.fchost.parent);
+            return -1;
+        }
+    }
+
     /* This filters either HBA or already created vHBA */
     if ((name = virGetFCHostNameByWWN(NULL, adapter.data.fchost.wwnn,
                                       adapter.data.fchost.wwpn))) {
@@ -565,14 +579,14 @@ createVport(virStoragePoolSourceAdapter adapter)
 
     if (!adapter.data.fchost.parent &&
         !(adapter.data.fchost.parent = virFindFCHostCapableVport(NULL))) {
-         virReportError(VIR_ERR_XML_ERROR, "%s",
+        virReportError(VIR_ERR_XML_ERROR, "%s",
                        _("'parent' for vHBA not specified, and "
                          "cannot find one on this host"));
          return -1;
-    }
 
-    if (virGetSCSIHostNumber(adapter.data.fchost.parent, &parent_host) < 0)
-        return -1;
+        if (virGetSCSIHostNumber(adapter.data.fchost.parent, &parent_host) < 0)
+            return -1;
+    }
 
     if (virManageVport(parent_host, adapter.data.fchost.wwpn,
                        adapter.data.fchost.wwnn, VPORT_CREATE) < 0)
-- 
1.9.3