[Libguestfs] [PATCH] v2v: -o libvirt: Get the <features/> right in the output XML (RHBZ#1159258).
Richard W.M. Jones
rjones at redhat.com
Fri Oct 31 16:05:03 UTC 2014
Implement what old virt-v2v did (from
lib/Sys/VirtConvert/Connection/LibVirtTarget.pm)
Thanks: Tingting Zheng, Matthew Booth
---
v2v/output_libvirt.ml | 118 ++++++++++++++++++++++++++++++++++++++++++++++---
v2v/output_libvirt.mli | 2 +-
v2v/output_local.ml | 13 +++++-
v2v/test-v2v-i-ova.xml | 5 ++-
4 files changed, 128 insertions(+), 10 deletions(-)
diff --git a/v2v/output_libvirt.ml b/v2v/output_libvirt.ml
index 305ce35..7fdc0d9 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 (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 +69,48 @@ 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 features =
+ let features_force = ["apic"; "pae"] in
+ List.fold_left (
+ fun set force ->
+ if StringSet.mem force target_features then
+ StringSet.add "apic" set
+ else
+ set
+ ) features features_force in
+
+ let features = List.sort compare (StringSet.elements features) in
let disks =
let block_prefix =
@@ -202,12 +271,36 @@ 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 +343,22 @@ 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 (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>
--
2.0.4
More information about the Libguestfs
mailing list