From 97ad621955e5be3ef3f8bbfc373f31b0027e7d6c Mon Sep 17 00:00:00 2001

From: "Richard W.M. Jones" <rjones@redhat.com>

Date: Fri, 31 Oct 2014 14:16:36 +0000

Subject: [PATCH] v2v: -o libvirt: Get the <features/> right in the output XML

 (RHBZ#1159258).

Implement what old virt-v2v did (from

lib/Sys/VirtConvert/Connection/LibVirtTarget.pm)

Thanks: Tingting Zheng, Matthew Booth

(cherry picked from commit 68dc488a4476caf742d5342307258dd72d0e2256)

---

 v2v/output_libvirt.ml  | 113 ++++++++++++++++++++++++++++++++++++++++++++++---

 v2v/output_libvirt.mli |   2 +-

 v2v/output_local.ml    |  13 +++++-

 v2v/test-v2v-i-ova.xml |   5 ++-

 4 files changed, 123 insertions(+), 10 deletions(-)

diff --git a/v2v/output_libvirt.ml b/v2v/output_libvirt.ml

index 59a390f..386d777 100644

--- a/v2v/output_libvirt.ml

+++ b/v2v/output_libvirt.ml

@@ -25,6 +25,42 @@ open Types

 open Utils

 open DOM

+module StringSet = Set.Make (String)

+

+let string_set_of_list =

+  List.fold_left (fun set x -> StringSet.add x set) StringSet.empty

+

+let target_features_of_capabilities_doc doc arch =

+  let xpathctx = Xml.xpath_new_context doc in

+  let expr =

+    (* NB: Pay attention to the square brackets.  This returns the

+     * <guest> nodes!

+     *)

+    sprintf "/capabilities/guest[arch[@name='%s']/domain/@type='kvm']" arch in

+  let obj = Xml.xpath_eval_expression xpathctx expr in

+

+  if Xml.xpathobj_nr_nodes obj < 1 then (

+    (* Old virt-v2v used to die here, but that seems unfair since the

+     * user has gone through conversion before we reach here.

+     *)

+    warning ~prog (f_"the target hypervisor does not support a %s KVM guest") arch;

+    []

+  ) else (

+    let node (* first matching <guest> *) = Xml.xpathobj_node doc obj 0 in

+    Xml.xpathctx_set_current_context xpathctx node;

+

+    (* Get guest/features/* nodes. *)

+    let obj = Xml.xpath_eval_expression xpathctx "features/*" in

+

+    let features = ref [] in

+    for i = 0 to Xml.xpathobj_nr_nodes obj - 1 do

+      let feature_node = Xml.xpathobj_node doc obj i in

+      let feature_name = Xml.node_name feature_node in

+      features := feature_name :: !features

+    done;

+    !features

+  )

+

 let append_child child = function

   | PCData _ | Comment _  -> assert false

   | Element e -> e.e_children <- e.e_children @ [child]

@@ -33,15 +69,43 @@ let append_attr attr = function

   | PCData _ | Comment _ -> assert false

   | Element e -> e.e_attrs <- e.e_attrs @ [attr]

-let create_libvirt_xml ?pool source targets guestcaps =

+let create_libvirt_xml ?pool source targets guestcaps target_features =

   let memory_k = source.s_memory /^ 1024L in

+  (* We have the machine features of the guest when it was on the

+   * source hypervisor (source.s_features).  We have the acpi flag

+   * which tells us whether acpi is required by this guest

+   * (guestcaps.gcaps_acpi).  And we have the set of hypervisor

+   * features supported by the target (target_features).  Combine all

+   * this into a final list of features.

+   *)

+  let features = string_set_of_list source.s_features in

+  let target_features = string_set_of_list target_features in

+

+  (* If the guest supports ACPI, add it to the output XML.  Conversely

+   * if the guest does not support ACPI, then we must drop it.

+   * (RHBZ#1159258)

+   *)

   let features =

-    List.filter (

-      fun feature ->

-        (* drop acpi if the guest doesn't support it *)

-        feature <> "acpi" || guestcaps.gcaps_acpi

-    ) source.s_features in

+    if guestcaps.gcaps_acpi then

+      StringSet.add "acpi" features

+    else

+      StringSet.remove "acpi" features in

+

+  (* Make sure we don't add any features which are not supported by

+   * the target hypervisor.

+   *)

+  let features = StringSet.inter(*section*) features target_features in

+

+  (* But if the target supports apic or pae then we should add them

+   * anyway (old virt-v2v did this).

+   *)

+  let force_features = string_set_of_list ["apic"; "pae"] in

+  let force_features =

+    StringSet.inter(*section*) force_features target_features in

+  let features = StringSet.union features force_features in

+

+  let features = List.sort compare (StringSet.elements features) in

   let disks =

     let block_prefix =

@@ -202,12 +266,36 @@ let create_libvirt_xml ?pool source targets guestcaps =

 class output_libvirt verbose oc output_pool = object

   inherit output verbose

+  val mutable capabilities_doc = None

+

   method as_options =

     match oc with

     | None -> sprintf "-o libvirt -os %s" output_pool

     | Some uri -> sprintf "-o libvirt -oc %s -os %s" uri output_pool

   method prepare_targets source targets =

+    (* Get the capabilities from libvirt. *)

+    let cmd =

+      match oc with

+      | None -> "virsh capabilities"

+      | Some uri -> sprintf "virsh -c %s capabilities" (quote uri) in

+    if verbose then printf "%s\n%!" cmd;

+    let xml = external_command ~prog cmd in

+    let xml = String.concat "\n" xml in

+

+    if verbose then printf "libvirt capabilities XML:\n%s\n%!" xml;

+

+    (* This just checks that the capabilities XML is well-formed,

+     * early so that we catch parsing errors before conversion.

+     *)

+    let doc = Xml.parse_memory xml in

+

+    (* Stash the capabilities XML, since we cannot get the bits we

+     * need from it until we know the guest architecture, which happens

+     * after conversion.

+     *)

+    capabilities_doc <- Some doc;

+

     (* Connect to output libvirt instance and check that the pool exists

      * and dump out its XML.

      *)

@@ -250,11 +338,22 @@ class output_libvirt verbose oc output_pool = object

       | Some uri ->

         sprintf "virsh -c %s pool-refresh %s"

           (quote uri) (quote output_pool) in

+    if verbose then printf "%s\n%!" cmd;

     if Sys.command cmd <> 0 then

       warning ~prog (f_"could not refresh libvirt pool %s") output_pool;

+    (* Parse the capabilities XML in order to get the supported features. *)

+    let doc =

+      match capabilities_doc with

+      | None -> assert false

+      | Some doc -> doc in

+    let target_features =

+      target_features_of_capabilities_doc doc guestcaps.gcaps_arch in

+

     (* Create the metadata. *)

-    let doc = create_libvirt_xml ~pool:output_pool source targets guestcaps in

+    let doc =

+      create_libvirt_xml ~pool:output_pool source targets

+        guestcaps target_features in

     let tmpfile, chan = Filename.open_temp_file "v2vlibvirt" ".xml" in

     DOM.doc_to_chan chan doc;

diff --git a/v2v/output_libvirt.mli b/v2v/output_libvirt.mli

index 25d4690..da41956 100644

--- a/v2v/output_libvirt.mli

+++ b/v2v/output_libvirt.mli

@@ -23,5 +23,5 @@ val output_libvirt : bool -> string option -> string -> Types.output

     {!Types.output} object specialized for writing output to

     libvirt. *)

-val create_libvirt_xml : ?pool:string -> Types.source -> Types.target list -> Types.guestcaps -> DOM.doc

+val create_libvirt_xml : ?pool:string -> Types.source -> Types.target list -> Types.guestcaps -> string list -> DOM.doc

 (** This is called from {!Output_local} to generate the libvirt XML. *)

diff --git a/v2v/output_local.ml b/v2v/output_local.ml

index db36f0e..ffcfad0 100644

--- a/v2v/output_local.ml

+++ b/v2v/output_local.ml

@@ -37,7 +37,18 @@ class output_local verbose dir = object

     ) targets

   method create_metadata source targets guestcaps _ =

-    let doc = Output_libvirt.create_libvirt_xml source targets guestcaps in

+    (* We don't know what target features the hypervisor supports, but

+     * assume a common set that libvirt supports.

+     *)

+    let target_features =

+      match guestcaps.gcaps_arch with

+      | "i686" -> [ "acpi"; "apic"; "pae" ]

+      | "x86_64" -> [ "acpi"; "apic" ]

+      | _ -> [] in

+

+    let doc =

+      Output_libvirt.create_libvirt_xml source targets

+        guestcaps target_features in

     let name = source.s_name in

     let file = dir // name ^ ".xml" in

diff --git a/v2v/test-v2v-i-ova.xml b/v2v/test-v2v-i-ova.xml

index ff83285..2d611f9 100644

--- a/v2v/test-v2v-i-ova.xml

+++ b/v2v/test-v2v-i-ova.xml

@@ -7,7 +7,10 @@

   <os>

     <type arch='x86_64'>hvm</type>

   </os>

-  <features/>

+  <features>

+    <acpi/>

+    <apic/>

+  </features>

   <on_poweroff>destroy</on_poweroff>

   <on_reboot>restart</on_reboot>

   <on_crash>restart</on_crash>

-- 

1.8.3.1