[pve-devel] [PATCH qemu-server] fix #1934: add qemu fw_cfg variables via 'tags'

[Fabian Grünbichler]

On August 23, 2019 2:03 pm, Dominik Csapak wrote:
> this add the 'tags' property to vms, which has the format:

why 'tags'? seems rather generic for what it does ;)

> 
> key=value(;key=value)*
> 
> each value will be set as
> 
> -fw_cfg 'name=opt/com.proxmox/$key,string=$value'
> (qemu recommends using a unique rfqdn)
> 
> this way, users can tag the vm with that information available inside
> e.g. under linux the value can be read under
> 
> /sys/firmware/qemu_fw_cfg/by_name/opt/com.proxmox./$key/raw
> 
> see the file docs/specs/fw_cfg.txt in the qemu repository for more
> details

if we introduce this, wouldn't it also make sense to allow to pass in 
snippet files via this interface (via file=$path instead of string=$value)?

> 
> maybe we can also use this in the future to show/set in the gui
> e.g. some grouping/ordering etc.
> 
> Signed-off-by: Dominik Csapak <d.csapak at proxmox.com>
> ---
>  PVE/QemuServer.pm | 37 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 37 insertions(+)
> 
> diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
> index 9f5bf56..d55a1ae 100644
> --- a/PVE/QemuServer.pm
> +++ b/PVE/QemuServer.pm
> @@ -232,6 +232,29 @@ my $watchdog_fmt = {
>  };
>  PVE::JSONSchema::register_format('pve-qm-watchdog', $watchdog_fmt);
>  
> +PVE::JSONSchema::register_format('pve-qm-tags', \&verify_tag_format);
> +sub verify_tag_format {
> +    my ($tagstring, $noerr) = @_;
> +
> +    if (!$tagstring) {
> +	return '';
> +    }
> +
> +    # forbid all characters not in range 0x20-0x7E
> +    for my $tag (split(';', $tagstring)) {
> +	my ($key, $value) = ($tag =~ m/^(.*)=(.*)$/);
> +	if ($key =~ m/[\x00-\x1F\x7F-\xFF]/) {
> +	    die "invalid character in tag key\n" if !$noerr;
> +	    return undef;
> +	}
> +	if ($value =~ m/[\x00-\x1F\x7F-\xFF]/) {
> +	    die "invalid character in tag value\n" if !$noerr;
> +	    return undef;
> +	}
> +    }
> +
> +    return $tagstring;
> +}
>  my $agent_fmt = {
>      enabled => {
>  	description => "Enable/disable Qemu GuestAgent.",
> @@ -672,6 +695,13 @@ EODESCR
>  	description => "Configure a audio device, useful in combination with QXL/Spice.",
>  	optional => 1
>      },
> +    tags => {
> +	description => "Specify key/value pairs to be added to qemu fw_cfg.",
> +	type => 'string',
> +	maxLength => 4096,
> +	format => 'pve-qm-tags',
> +	optional => 1,
> +    },
>  };
>  
>  my $cicustom_fmt = {
> @@ -4152,6 +4182,13 @@ sub config_to_command {
>  	push @$cmd, '-loadstate', $statepath;
>      }
>  
> +    if ($conf->{tags}) {
> +	for my $tag (split(';', $conf->{tags})) {
> +	    my ($key, $value) = ($tag =~ m/^(.*)=(.*)$/);
> +	    push @$cmd, '-fw_cfg', "name=opt/com.proxmox/$key,string=$value";
> +	}
> +    }
> +
>      # add custom args
>      if ($conf->{args}) {
>  	my $aa = PVE::Tools::split_args($conf->{args});
> -- 
> 2.20.1
> 
> 
> _______________________________________________
> pve-devel mailing list
> pve-devel at pve.proxmox.com
> https://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
> 
>