[PATCH pve-manager v5 14/21] api: add endpoint querying available CPU flags cluster-wide

[Arthur Bied-Charreton <a.bied-charreton@proxmox.com>]

Add endpoint at `/cluster/qemu/cpu-flags` allowing to query the CPU
flags available on the whole cluster, filtered by acceleration type
(kvm/tcg).

For each flag, a list of nodes supporting it is returned. This gives an
accurate picture of which flags will actually be accepted by QEMU when
starting a VM.

Currently only return available flags for x86_64, see documentation of
query_available_cpu_flags.

Signed-off-by: Arthur Bied-Charreton <a.bied-charreton@proxmox.com>
---
 PVE/API2/Cluster.pm               |  7 ++++
 PVE/API2/Cluster/Makefile         |  6 ++-
 PVE/API2/Cluster/Qemu.pm          | 41 +++++++++++++++++++
 PVE/API2/Cluster/Qemu/CPUFlags.pm | 68 +++++++++++++++++++++++++++++++
 PVE/API2/Cluster/Qemu/Makefile    | 17 ++++++++
 5 files changed, 137 insertions(+), 2 deletions(-)
 create mode 100644 PVE/API2/Cluster/Qemu.pm
 create mode 100644 PVE/API2/Cluster/Qemu/CPUFlags.pm
 create mode 100644 PVE/API2/Cluster/Qemu/Makefile

diff --git a/PVE/API2/Cluster.pm b/PVE/API2/Cluster.pm
index a800dbbd..aa493013 100644
--- a/PVE/API2/Cluster.pm
+++ b/PVE/API2/Cluster.pm
@@ -31,6 +31,7 @@ use PVE::API2::Cluster::Jobs;
 use PVE::API2::Cluster::Mapping;
 use PVE::API2::Cluster::MetricServer;
 use PVE::API2::Cluster::Notifications;
+use PVE::API2::Cluster::Qemu;
 use PVE::API2::ClusterConfig;
 use PVE::API2::Firewall::Cluster;
 use PVE::API2::HAConfig;
@@ -59,6 +60,11 @@ __PACKAGE__->register_method({
     path => 'notifications',
 });
 
+__PACKAGE__->register_method({
+    subclass => "PVE::API2::Cluster::Qemu",
+    path => 'qemu',
+});
+
 __PACKAGE__->register_method({
     subclass => "PVE::API2::ClusterConfig",
     path => 'config',
@@ -166,6 +172,7 @@ __PACKAGE__->register_method({
             { name => 'notifications' },
             { name => 'nextid' },
             { name => 'options' },
+            { name => 'qemu' },
             { name => 'replication' },
             { name => 'resources' },
             { name => 'status' },
diff --git a/PVE/API2/Cluster/Makefile b/PVE/API2/Cluster/Makefile
index 1f9a95e6..d3a56830 100644
--- a/PVE/API2/Cluster/Makefile
+++ b/PVE/API2/Cluster/Makefile
@@ -1,7 +1,8 @@
 include ../../../defines.mk
 
 SUBDIRS=Mapping		\
-	BulkAction
+	BulkAction 		\
+	Qemu
 
 # for node independent, cluster-wide applicable, API endpoints
 # ensure we do not conflict with files shipped by pve-cluster!!
@@ -12,7 +13,8 @@ PERLSOURCE= 			\
 	Jobs.pm				\
 	Mapping.pm			\
 	MetricServer.pm		\
-	Notifications.pm
+	Notifications.pm	\
+	Qemu.pm
 
 all:
 
diff --git a/PVE/API2/Cluster/Qemu.pm b/PVE/API2/Cluster/Qemu.pm
new file mode 100644
index 00000000..f09481b2
--- /dev/null
+++ b/PVE/API2/Cluster/Qemu.pm
@@ -0,0 +1,41 @@
+package PVE::API2::Cluster::Qemu;
+
+use v5.36;
+
+use PVE::API2::Cluster::Qemu::CPUFlags;
+
+use base qw(PVE::RESTHandler);
+
+__PACKAGE__->register_method({
+    subclass => "PVE::API2::Cluster::Qemu::CPUFlags",
+    path => "cpu-flags",
+});
+
+__PACKAGE__->register_method({
+    name => 'index',
+    path => '',
+    method => 'GET',
+    description => "Cluster-wide QEMU index",
+    permissions => { user => 'all' },
+    parameters => {
+        additionalProperties => 0,
+        properties => {},
+    },
+    returns => {
+        type => 'array',
+        items => {
+            type => "object",
+            properties => {},
+        },
+        links => [{ rel => 'child', href => "{name}" }],
+    },
+    code => sub {
+        my ($param) = @_;
+
+        return [
+            { name => 'cpu-flags' },
+        ];
+    },
+});
+
+1;
diff --git a/PVE/API2/Cluster/Qemu/CPUFlags.pm b/PVE/API2/Cluster/Qemu/CPUFlags.pm
new file mode 100644
index 00000000..4d11197f
--- /dev/null
+++ b/PVE/API2/Cluster/Qemu/CPUFlags.pm
@@ -0,0 +1,68 @@
+package PVE::API2::Cluster::Qemu::CPUFlags;
+
+use v5.36;
+
+use PVE::JSONSchema qw(get_standard_option);
+use PVE::RESTHandler;
+use PVE::Tools qw(extract_param);
+
+use PVE::QemuServer::CPUFlags;
+use PVE::QemuServer::Helpers;
+
+use base qw(PVE::RESTHandler);
+
+__PACKAGE__->register_method({
+    name => 'index',
+    path => '',
+    method => 'GET',
+    description => "List of available CPU flags. Currently only implemented for x86_64,"
+        . " returns an empty list for aarch64.",
+    permissions => { check => ['perm', '/nodes', ['Sys.Audit']] },
+    parameters => {
+        additionalProperties => 0,
+        properties => {
+            arch => get_standard_option('pve-qm-cpu-arch', { optional => 1 }),
+            accel => {
+                description => 'Acceleration type to check node compatibility for.',
+                type => 'string',
+                enum => [qw(kvm tcg)],
+                optional => 1,
+                default => 'kvm',
+            },
+        },
+    },
+    returns => {
+        type => 'array',
+        items => {
+            type => 'object',
+            properties => {
+                name => {
+                    type => 'string',
+                    description => "Name of the CPU flag.",
+                },
+                description => {
+                    type => 'string',
+                    description => "Description of the CPU flag.",
+                    optional => 1,
+                },
+                'supported-on' => {
+                    description =>
+                        'List of nodes supporting the flag with the selected acceleration type ("accel").',
+                    type => 'array',
+                    items => get_standard_option('pve-node'),
+                    optional => 1,
+                },
+            },
+        },
+    },
+    code => sub {
+        my ($param) = @_;
+
+        my $arch = extract_param($param, 'arch') // PVE::QemuServer::Helpers::get_host_arch();
+        my $accel = extract_param($param, 'accel') // 'kvm';
+
+        return PVE::QemuServer::CPUFlags::query_available_cpu_flags($accel, 0, $arch);
+    },
+});
+
+1;
diff --git a/PVE/API2/Cluster/Qemu/Makefile b/PVE/API2/Cluster/Qemu/Makefile
new file mode 100644
index 00000000..2ab3e0b1
--- /dev/null
+++ b/PVE/API2/Cluster/Qemu/Makefile
@@ -0,0 +1,17 @@
+include ../../../../defines.mk
+
+# for node independent, cluster-wide applicable, API endpoints
+# ensure we do not conflict with files shipped by pve-cluster!!
+PERLSOURCE= 	\
+	CPUFlags.pm
+
+all:
+
+.PHONY: clean
+clean:
+	rm -rf *~
+
+.PHONY: install
+install: ${PERLSOURCE}
+	install -d ${PERLLIBDIR}/PVE/API2/Cluster/Qemu
+	install -m 0644 ${PERLSOURCE} ${PERLLIBDIR}/PVE/API2/Cluster/Qemu
-- 
2.47.3