plugin: add machine version to qemu_blockdev_options() interface

Plugins can guard based on the machine version to be able to switch
drivers or options in a safe way without the risk of breaking older
versions.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>

src/PVE/Storage.pm

@@ -721,7 +721,7 @@ sub abs_filesystem_path {
 
 # see the documentation for the plugin method
 sub qemu_blockdev_options {
-    my ($cfg, $volid, $options) = @_;
+    my ($cfg, $volid, $machine_version, $options) = @_;
 
     my ($storeid, $volname) = parse_volume_id($volid);
 
@@ -733,7 +733,7 @@ sub qemu_blockdev_options {
     die "cannot use volume of type '$vtype' as a QEMU blockdevice\n"
         if $vtype ne 'images' && $vtype ne 'iso' && $vtype ne 'import';
 
-    return $plugin->qemu_blockdev_options($scfg, $storeid, $volname, $options);
+    return $plugin->qemu_blockdev_options($scfg, $storeid, $volname, $machine_version, $options);
 }
 
 # used as last resort to adapt volnames when migrating

src/PVE/Storage/ISCSIDirectPlugin.pm

@@ -111,7 +111,7 @@ sub path {
 }
 
 sub qemu_blockdev_options {
-    my ($class, $scfg, $storeid, $volname, $options) = @_;
+    my ($class, $scfg, $storeid, $volname, $machine_version, $options) = @_;
 
     die "volume snapshot is not possible on iscsi device\n"
         if $options->{'snapshot-name'};

src/PVE/Storage/Plugin.pm

@@ -1965,7 +1965,8 @@ sub rename_volume {
 
 =head3 qemu_blockdev_options
 
-    $blockdev = $plugin->qemu_blockdev_options($scfg, $storeid, $volname, $options)
+    $blockdev =
+        $plugin->qemu_blockdev_options($scfg, $storeid, $volname, $machine_version, $options)
 
 Returns a hash reference with the basic options needed to open the volume via QEMU's C<-blockdev>
 API. This at least requires a C<< $blockdev->{driver} >> and a reference to the image, e.g.
@@ -1992,6 +1993,13 @@ Arguments:
 
 =item C<$volume>: The volume name.
 
+=item C<$machine_version>: The QEMU machine version for which the block device will be used. If you
+want to change drivers or change driver options, you should use this as a guard, so that only
+machines with a new enough version will use the new driver or options. Machines with an older
+version should still get the old driver and options. The version is a string
+C<${major}.${minor}+pve${pve_version}>. The pve version is used for certain downstream changes to
+machine models and should be (mostly) irrelevant for third-party plugins.
+
 =item C<$options>: A hash reference with additional options.
 
 =over
@@ -2019,7 +2027,7 @@ volume itself.
 =cut
 
 sub qemu_blockdev_options {
-    my ($class, $scfg, $storeid, $volname, $options) = @_;
+    my ($class, $scfg, $storeid, $volname, $machine_version, $options) = @_;
 
     my $blockdev = {};
 

src/PVE/Storage/RBDPlugin.pm

@@ -524,7 +524,7 @@ sub path {
 }
 
 sub qemu_blockdev_options {
-    my ($class, $scfg, $storeid, $volname, $options) = @_;
+    my ($class, $scfg, $storeid, $volname, $machine_version, $options) = @_;
 
     my $cmd_option = PVE::CephConfig::ceph_connect_option($scfg, $storeid);
     my ($name) = ($class->parse_volname($volname))[1];

src/PVE/Storage/ZFSPlugin.pm

@@ -248,7 +248,7 @@ sub path {
 }
 
 sub qemu_blockdev_options {
-    my ($class, $scfg, $storeid, $volname, $options) = @_;
+    my ($class, $scfg, $storeid, $volname, $machine_version, $options) = @_;
 
     die "direct access to snapshots not implemented\n"
         if $options->{'snapshot-name'};

src/PVE/Storage/ZFSPoolPlugin.pm

@@ -163,7 +163,7 @@ sub path {
 }
 
 sub qemu_blockdev_options {
-    my ($class, $scfg, $storeid, $volname, $options) = @_;
+    my ($class, $scfg, $storeid, $volname, $machine_version, $options) = @_;
 
     my $format = ($class->parse_volname($volname))[6];