[libvirt] [PATCH v5] npiv: Auto-generate WWN if it's not specified

[Osier Yang]

The auto-generated WWN comply with the new addressing schema of WWN:

<quote>
the first nibble is either hex 5 or 6 followed by a 3-byte vendor
identifier and 36 bits for a vendor-specified serial number.
</quote>

We choose hex 5 for the first nibble. And use Qumranet's OUI
(00:1A:4A) as the 3-byte vendor indentifier. The last 36 bits
are auto-generated.
---
 src/conf/node_device_conf.c |   36 +++++++++++++++++++-----------------
 src/libvirt_private.syms    |    1 +
 src/util/virrandom.c        |   18 ++++++++++++++++++
 src/util/virrandom.h        |    1 +
 4 files changed, 39 insertions(+), 17 deletions(-)

diff --git a/src/conf/node_device_conf.c b/src/conf/node_device_conf.c
index d9dc9ac..127a4ae 100644
--- a/src/conf/node_device_conf.c
+++ b/src/conf/node_device_conf.c
@@ -37,6 +37,7 @@
 #include "buf.h"
 #include "uuid.h"
 #include "pci.h"
+#include "virrandom.h"
 
 #define VIR_FROM_THIS VIR_FROM_NODEDEV
 
@@ -63,19 +64,12 @@ VIR_ENUM_IMPL(virNodeDevHBACap, VIR_NODE_DEV_CAP_HBA_LAST,
 static int
 virNodeDevCapsDefParseString(const char *xpath,
                              xmlXPathContextPtr ctxt,
-                             char **string,
-                             virNodeDeviceDefPtr def,
-                             const char *missing_error_fmt)
+                             char **string)
 {
     char *s;
 
-    s = virXPathString(xpath, ctxt);
-    if (s == NULL) {
-        virNodeDeviceReportError(VIR_ERR_INTERNAL_ERROR,
-                                 missing_error_fmt,
-                                 def->name);
+    if (!(s = virXPathString(xpath, ctxt)))
         return -1;
-    }
 
     *string = s;
     return 0;
@@ -763,18 +757,26 @@ virNodeDevCapScsiHostParseXML(xmlXPathContextPtr ctxt,
 
             if (virNodeDevCapsDefParseString("string(./wwnn[1])",
                                              ctxt,
-                                             &data->scsi_host.wwnn,
-                                             def,
-                                             _("no WWNN supplied for '%s'")) < 0) {
-                goto out;
+                                             &data->scsi_host.wwnn) < 0) {
+                if (virRandomGenerateWWN(&data->scsi_host.wwnn) < 0) {
+                    virNodeDeviceReportError(VIR_ERR_INTERNAL_ERROR,
+                                             _("no WWNN supplied for '%s', and "
+                                               "auto-generation failed"),
+                                             def->name);
+                    goto out;
+                }
             }
 
             if (virNodeDevCapsDefParseString("string(./wwpn[1])",
                                              ctxt,
-                                             &data->scsi_host.wwpn,
-                                             def,
-                                             _("no WWPN supplied for '%s'")) < 0) {
-                goto out;
+                                             &data->scsi_host.wwpn) < 0) {
+                if (virRandomGenerateWWN(&data->scsi_host.wwpn) < 0) {
+                    virNodeDeviceReportError(VIR_ERR_INTERNAL_ERROR,
+                                             _("no WWPN supplied for '%s', and "
+                                               "auto-generation failed"),
+                                             def->name);
+                    goto out;
+                }
             }
 
             ctxt->node = orignode2;
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index d6ad36c..421986b 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -1373,6 +1373,7 @@ virPidFileDeletePath;
 
 # virrandom.h
 virRandomBits;
+virRandomGenerateWWN;
 virRandomInitialize;
 
 
diff --git a/src/util/virrandom.c b/src/util/virrandom.c
index ec0cf03..3116275 100644
--- a/src/util/virrandom.c
+++ b/src/util/virrandom.c
@@ -22,10 +22,15 @@
 #include <config.h>
 
 #include <stdlib.h>
+#include <inttypes.h>
 
 #include "virrandom.h"
 #include "threads.h"
 #include "count-one-bits.h"
+#include "util.h"
+#include "virterror_internal.h"
+
+#define VIR_FROM_THIS VIR_FROM_NONE
 
 static char randomState[128];
 static struct random_data randomData;
@@ -79,3 +84,16 @@ uint64_t virRandomBits(int nbits)
     virMutexUnlock(&randomLock);
     return ret;
 }
+
+#define QUMRANET_OUI "001a4a"
+
+int
+virRandomGenerateWWN(char **wwn) {
+   if (virAsprintf(wwn, "5" QUMRANET_OUI "%09" PRIx64,
+                   virRandomBits(36)) < 0) {
+       virReportOOMError();
+       return -1;
+   }
+
+   return 0;
+}
diff --git a/src/util/virrandom.h b/src/util/virrandom.h
index e180a2f..443451e 100644
--- a/src/util/virrandom.h
+++ b/src/util/virrandom.h
@@ -27,5 +27,6 @@
 
 int virRandomInitialize(uint32_t seed) ATTRIBUTE_RETURN_CHECK;
 uint64_t virRandomBits(int nbits);
+int virRandomGenerateWWN(char **wwn);
 
 #endif /* __VIR_RANDOM_H__ */
-- 
1.7.7.3