Do not drop kernel cmdline for xen pv domains

Kernel cmdline args can be passed to xen pv domains even when a
bootloader is specified.  The current config-to-sxpr mapping
ignores cmdline when bootloader is present.

Since the xend sub-driver is used with many xen toolstack versions,
this patch takes conservative approach of adding an else block to
existing !def->os.bootloader, and only appends sxpr if def->os.cmdline
is non-NULL.

V2: Fix existing testcase broken by this patch and add new testcases

docs/schemas/domain.rng

@@ -556,9 +556,11 @@
   </define>
   <define name="osbootkernel">
     <interleave>
-      <element name="kernel">
-        <ref name="absFilePath"/>
-      </element>
+      <optional>
+        <element name="kernel">
+          <ref name="absFilePath"/>
+        </element>
+      </optional>
       <optional>
         <element name="initrd">
           <ref name="absFilePath"/>

src/xenxs/xen_sxpr.c

@@ -2261,6 +2261,12 @@ xenFormatSxpr(virConnectPtr conn,
         }
 
         virBufferAddLit(&buf, "))");
+    } else {
+        /* PV domains accept kernel cmdline args */
+        if (def->os.cmdline) {
+            virBufferEscapeSexpr(&buf, "(image (linux (args '%s')))",
+                                 def->os.cmdline);
+        }
     }
 
     for (i = 0 ; i < def->ndisks ; i++)

tests/sexpr2xmldata/sexpr2xml-pv-bootloader-cmdline.sexpr

+(domain (domid 6)(name 'pvtest')(memory 420)(maxmem 420)(vcpus 2)\
+(uuid '596a5d2171f48fb2e068e2386a5c413e')(bootloader '/usr/bin/pygrub')\
+(bootloader_args '-q')(image (linux (args 'xenfb.video=8,1280,1024')))\
+(on_poweroff 'destroy')(on_reboot 'destroy')(on_crash 'destroy')\
+(device (vbd (dev 'xvda')(uname 'file:/root/some.img')(mode 'w'))))

tests/sexpr2xmldata/sexpr2xml-pv-bootloader-cmdline.xml

+<domain type='xen' id='6'>
+  <name>pvtest</name>
+  <uuid>596a5d21-71f4-8fb2-e068-e2386a5c413e</uuid>
+  <memory>430080</memory>
+  <currentMemory>430080</currentMemory>
+  <vcpu>2</vcpu>
+  <bootloader>/usr/bin/pygrub</bootloader>
+  <bootloader_args>-q</bootloader_args>
+  <os>
+    <type>linux</type>
+    <cmdline>xenfb.video=8,1280,1024</cmdline>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>destroy</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <disk type='file' device='disk'>
+      <driver name='file'/>
+      <source file='/root/some.img'/>
+      <target dev='xvda' bus='xen'/>
+    </disk>
+    <console type='pty'>
+      <target type='xen' port='0'/>
+    </console>
+  </devices>
+</domain>

tests/sexpr2xmltest.c

@@ -134,6 +134,7 @@ mymain(void)
     DO_TEST("pv-vfb-type-crash", "pv-vfb-type-crash", 3);
     DO_TEST("fv-autoport", "fv-autoport", 3);
     DO_TEST("pv-bootloader", "pv-bootloader", 1);
+    DO_TEST("pv-bootloader-cmdline", "pv-bootloader-cmdline", 1);
     DO_TEST("pv-vcpus", "pv-vcpus", 1);
 
     DO_TEST("disk-file", "disk-file", 2);

tests/xml2sexprdata/xml2sexpr-disk-block-shareable.sexpr

 (vm (name 'pvtest')(memory 384)(maxmem 512)(vcpus 1)\
 (uuid '49a0c6ff-c066-5392-6498-3632d093c2e7')(bootloader '/usr/bin/pygrub')\
 (on_poweroff 'destroy')(on_reboot 'restart')(on_crash 'restart')\
+(image (linux (args 'ro root=/dev/VolGroup00/LogVol00')))\
 (device (tap (dev 'xvda')(uname 'tap:aio:/var/lib/xen/images/rhel5pv.img')\
 (mode 'w!')))(device (vif (mac '00:16:3e:23:9e:eb')(bridge 'xenbr0')\
 (script 'vif-bridge'))))\

tests/xml2sexprdata/xml2sexpr-pv-bootloader-cmdline.sexpr

+(vm (name 'pvtest')(memory 420)(maxmem 420)(vcpus 2)\
+(uuid '596a5d21-71f4-8fb2-e068-e2386a5c413e')(bootloader '/usr/bin/pygrub')\
+(bootloader_args '-q')(on_poweroff 'destroy')(on_reboot 'destroy')\
+(on_crash 'destroy')(image (linux (args 'xenfb.video=8,1280,1024')))\
+(device (vbd (dev 'xvda')(uname 'file:/root/some.img')(mode 'w'))))\

tests/xml2sexprdata/xml2sexpr-pv-bootloader-cmdline.xml

+<domain type='xen' id='15'>
+  <name>pvtest</name>
+  <uuid>596a5d2171f48fb2e068e2386a5c413e</uuid>
+  <bootloader>/usr/bin/pygrub</bootloader>
+  <bootloader_args>-q</bootloader_args>
+ <os>
+    <type>linux</type>
+    <cmdline>xenfb.video=8,1280,1024</cmdline>
+  </os>
+  <memory>430080</memory>
+  <vcpu>2</vcpu>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>destroy</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <disk type='file' device='disk'>
+      <source file='/root/some.img'/>
+      <target dev='xvda'/>
+    </disk>
+    <console tty='/dev/pts/4'/>
+  </devices>
+</domain>

tests/xml2sexprtest.c

@@ -116,6 +116,7 @@ mymain(void)
     DO_TEST("pv-vfb-new", "pv-vfb-new", "pvtest", 3);
     DO_TEST("pv-vfb-new-auto", "pv-vfb-new-auto", "pvtest", 3);
     DO_TEST("pv-bootloader", "pv-bootloader", "pvtest", 1);
+    DO_TEST("pv-bootloader-cmdline", "pv-bootloader-cmdline", "pvtest", 1);
     DO_TEST("pv-vcpus", "pv-vcpus", "pvtest", 1);
 
     DO_TEST("disk-file", "disk-file", "pvtest", 2);