[libvirt] [PATCH 1/4] Introduce API virNodeDeviceLookupSCSIHostByWWN

[Osier Yang]

Since the name (like scsi_host10) is not stable for vHBA, (it can
be changed either after recreating or system rebooting), current
API virNodeDeviceLookupByName is not nice to use for management app
in this case. (E.g. one wants to destroy the vHBA whose name has
been changed after system rebooting, he has to find out current
name first).

Later patches will support the persistent vHBA via storage pool,
with which one can identify the vHBA stably by the wwnn && wwpn
pair.

So this new API comes.
---
 include/libvirt/libvirt.h.in |    5 ++++
 src/driver.h                 |    6 +++++
 src/libvirt.c                |   46 ++++++++++++++++++++++++++++++++++++++++++
 src/libvirt_public.syms      |    1 +
 4 files changed, 58 insertions(+), 0 deletions(-)

diff --git a/include/libvirt/libvirt.h.in b/include/libvirt/libvirt.h.in
index c1233f6..563ca27 100644
--- a/include/libvirt/libvirt.h.in
+++ b/include/libvirt/libvirt.h.in
@@ -3156,6 +3156,11 @@ int                     virConnectListAllNodeDevices (virConnectPtr conn,
 virNodeDevicePtr        virNodeDeviceLookupByName (virConnectPtr conn,
                                                    const char *name);
 
+virNodeDevicePtr        virNodeDeviceLookupSCSIHostByWWN (virConnectPtr conn,
+                                                          const char *wwnn,
+                                                          const char *wwpn,
+                                                          unsigned int flags);
+
 const char *            virNodeDeviceGetName     (virNodeDevicePtr dev);
 
 const char *            virNodeDeviceGetParent   (virNodeDevicePtr dev);
diff --git a/src/driver.h b/src/driver.h
index 01c95cf..bdac101 100644
--- a/src/driver.h
+++ b/src/driver.h
@@ -1547,6 +1547,11 @@ typedef int (*virDevMonListAllNodeDevices)(virConnectPtr conn,
 typedef virNodeDevicePtr (*virDevMonDeviceLookupByName)(virConnectPtr conn,
                                                         const char *name);
 
+typedef virNodeDevicePtr (*virDevMonDeviceLookupSCSIHostByWWN)(virConnectPtr conn,
+                                                               const char *wwnn,
+                                                               const char *wwpn,
+                                                               unsigned int flags);
+
 typedef char * (*virDevMonDeviceGetXMLDesc)(virNodeDevicePtr dev,
                                             unsigned int flags);
 
@@ -1578,6 +1583,7 @@ struct _virDeviceMonitor {
     virDevMonListDevices        listDevices;
     virDevMonListAllNodeDevices listAllNodeDevices;
     virDevMonDeviceLookupByName deviceLookupByName;
+    virDevMonDeviceLookupSCSIHostByWWN  deviceLookupSCSIHostByWWN;
     virDevMonDeviceGetXMLDesc   deviceGetXMLDesc;
     virDevMonDeviceGetParent    deviceGetParent;
     virDevMonDeviceNumOfCaps    deviceNumOfCaps;
diff --git a/src/libvirt.c b/src/libvirt.c
index a783fa6..0a2ade7 100644
--- a/src/libvirt.c
+++ b/src/libvirt.c
@@ -14334,6 +14334,52 @@ error:
     return NULL;
 }
 
+/**
+ * virNodeDeviceLookupSCSIHostByWWN:
+ * @conn: pointer to the hypervisor connection
+ * @wwnn: WWNN of the SCSI Host.
+ * @wwpn: WWPN of the SCSI Host.
+ * @flags: extra flags; not used yet, so callers should always pass 0
+ *
+ * Lookup SCSI Host which is capable with 'fc_host' by its WWNN and WWPN.
+ *
+ * Returns a virNodeDevicePtr if found, NULL otherwise.
+ */
+virNodeDevicePtr
+virNodeDeviceLookupSCSIHostByWWN(virConnectPtr conn,
+                                 const char *wwnn,
+                                 const char *wwpn,
+                                 unsigned int flags)
+{
+    VIR_DEBUG("conn=%p, wwnn=%p, wwpn=%p, flags=%x", conn, wwnn, wwpn, flags);
+
+    virResetLastError();
+
+    if (!VIR_IS_CONNECT(conn)) {
+        virLibConnError(VIR_ERR_INVALID_CONN, __FUNCTION__);
+        virDispatchError(NULL);
+        return NULL;
+    }
+
+    virCheckNonNullArgGoto(wwnn, error);
+    virCheckNonNullArgGoto(wwpn, error);
+
+    if (conn->deviceMonitor &&
+        conn->deviceMonitor->deviceLookupSCSIHostByWWN) {
+        virNodeDevicePtr ret;
+        ret = conn->deviceMonitor->deviceLookupSCSIHostByWWN(conn, wwnn,
+                                                             wwpn, flags);
+        if (!ret)
+            goto error;
+        return ret;
+    }
+
+    virLibConnError(VIR_ERR_NO_SUPPORT, __FUNCTION__);
+
+error:
+    virDispatchError(conn);
+    return NULL;
+}
 
 /**
  * virNodeDeviceGetXMLDesc:
diff --git a/src/libvirt_public.syms b/src/libvirt_public.syms
index 2107519..abd5d4a 100644
--- a/src/libvirt_public.syms
+++ b/src/libvirt_public.syms
@@ -583,6 +583,7 @@ LIBVIRT_1.0.1 {
 LIBVIRT_1.0.2 {
     global:
         virDomainOpenChannel;
+        virNodeDeviceLookupSCSIHostByWWN;
 } LIBVIRT_1.0.1;
 
 # .... define new API here using predicted next version number ....
-- 
1.7.7.6