qemu: Allow the disk wwn to have "0x" prefix

The recent qemu requires "0x" prefix for the disk wwn, this patch
changes virValidateWWN to allow the prefix, and prepend "0x" if
it's not specified. E.g.

qemu-kvm: -device scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,\
drive=drive-scsi0-0-0-0,id=scsi0-0-0-0,wwn=6000c60016ea71ad:
Property 'scsi-hd.wwn' doesn't take value '6000c60016ea71ad'

Though it's a qemu regression, but it's nice to allow the prefix,
and doesn't hurt for us to always output "0x".

docs/schemas/basictypes.rng

@@ -280,7 +280,7 @@
 
   <define name='wwn'>
     <data type='string'>
-      <param name='pattern'>[0-9a-fA-F]{16}</param>
+      <param name='pattern'>(0x)?[0-9a-fA-F]{16}</param>
     </data>
   </define>
 

src/qemu/qemu_command.c

@@ -3358,8 +3358,12 @@ qemuBuildDriveDevStr(virDomainDefPtr def,
                               disk->blockio.physical_block_size);
     }
 
-    if (disk->wwn)
+    if (disk->wwn) {
+        if (STRPREFIX(disk->wwn, "0x"))
             virBufferAsprintf(&opt, ",wwn=%s", disk->wwn);
+        else
+            virBufferAsprintf(&opt, ",wwn=0x%s", disk->wwn);
+    }
 
     if (disk->vendor)
         virBufferAsprintf(&opt, ",vendor=%s", disk->vendor);

src/util/virutil.c

@@ -3228,12 +3228,18 @@ bool virIsDevMapperDevice(const char *dev_name ATTRIBUTE_UNUSED)
 bool
 virValidateWWN(const char *wwn) {
     int i;
+    const char *p = wwn;
 
-    for (i = 0; wwn[i]; i++)
+    if (STRPREFIX(wwn, "0x")) {
-        if (!c_isxdigit(wwn[i]))
+        p += 2;
+    }
+
+    for (i = 0; p[i]; i++) {
+        if (!c_isxdigit(p[i]))
             break;
+    }
 
-    if (i != 16 || wwn[i]) {
+    if (i != 16 || p[i]) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                        _("Malformed wwn: %s"));
         return false;

tests/qemuxml2argvdata/qemuxml2argv-disk-ide-wwn.args

@@ -2,5 +2,5 @@ LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test \
 /usr/bin/qemu -S -M pc -m 214 -smp 1 -nographic -nodefaults \
 -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot c -usb \
 -drive file=/dev/HostVG/QEMUGuest1,if=none,id=drive-ide0-0-1,serial=WD-WMAP9A966149 \
--device ide-hd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1,wwn=5000c50015ea71ad \
+-device ide-hd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1,wwn=0x5000c50015ea71ad \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3

tests/qemuxml2argvdata/qemuxml2argv-disk-scsi-disk-wwn.args

@@ -5,7 +5,7 @@ LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test \
 -device lsi,id=scsi1,bus=pci.0,addr=0x4 \
 -usb \
 -drive file=/dev/HostVG/QEMUGuest1,if=none,id=drive-scsi0-0-1-0 \
--device scsi-cd,bus=scsi0.0,channel=0,scsi-id=1,lun=0,drive=drive-scsi0-0-1-0,id=scsi0-0-1-0,wwn=5000c50015ea71ac \
+-device scsi-cd,bus=scsi0.0,channel=0,scsi-id=1,lun=0,drive=drive-scsi0-0-1-0,id=scsi0-0-1-0,wwn=0x5000c50015ea71ac \
 -drive file=/dev/HostVG/QEMUGuest2,if=none,id=drive-scsi0-0-0-0 \
--device scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0,wwn=5000c50015ea71ad \
+-device scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0,wwn=0x5000c50015ea71ad \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5

tests/qemuxml2argvdata/qemuxml2argv-disk-scsi-disk-wwn.xml

@@ -25,7 +25,7 @@
       <source dev='/dev/HostVG/QEMUGuest2'/>
       <target dev='sdb' bus='scsi'/>
       <address type='drive' controller='0' bus='0' target='0' unit='0'/>
-      <wwn>5000c50015ea71ad</wwn>
+      <wwn>0x5000c50015ea71ad</wwn>
     </disk>
     <controller type='usb' index='0'/>
     <controller type='scsi' index='0' model='virtio-scsi'/>