Re: [pve-devel] [PATCH storage 1/2] rbd: fix #3286 add namespace support

[Thomas Lamprecht <t.lamprecht@proxmox.com>]

On 01.04.21 15:40, Aaron Lauterer wrote:
> This patch introduces support for Cephs RBD namespaces.
> 
> A new storage config parameter 'namespace' defines the namespace to be
> used for the RBD storage.
> 
> The namespace must already exist in the Ceph cluster as it is not
> automatically created.
> 
> The main intention is to use this for external Ceph clusters. With
> namespaces, each PVE cluster can get its own namespace and will not
> conflict with other PVE clusters.
> 
> Signed-off-by: Aaron Lauterer <a.lauterer@proxmox.com>
> 
> remove just style changes
> ---
> Changes from RFC:
> 
> add --namespace parameter centrally in sub $build_cmd. All commands
> except one (rbd unmap) support it. To handle commands that don't support
> it, a hash with them was introduced.
> 
> In a few places paths (FS, Ceph hierarchy) are needed. These are the
> places scattered throughout the plugin where the namespace is inserted
> if it is configured.
> 
>  PVE/Storage/RBDPlugin.pm | 34 ++++++++++++++++++++++++++++------
>  1 file changed, 28 insertions(+), 6 deletions(-)
> 
> diff --git a/PVE/Storage/RBDPlugin.pm b/PVE/Storage/RBDPlugin.pm
> index fab6d57..2d78f40 100644
> --- a/PVE/Storage/RBDPlugin.pm
> +++ b/PVE/Storage/RBDPlugin.pm
> @@ -27,7 +27,9 @@ my $add_pool_to_disk = sub {
>  
>      my $pool =  $scfg->{pool} ? $scfg->{pool} : 'rbd';
>  
> -    return "$pool/$disk";
> +    my $namespace = $scfg->{namespace} ? "/$scfg->{namespace}" : "";

can I have "0" as namespace? as then above check may break. Maybe do:

my $namespace = '/' . ($scfg->{namespace} // '');

return "${pool}${namespace}${disk}";



> +
> +    return "${pool}${namespace}/${disk}";
>  };
>  
>  my $build_cmd = sub {
> @@ -38,6 +40,14 @@ my $build_cmd = sub {
>  
>      my $cmd = [$binary, '-p', $pool];
>  
> +    # some subcommands will fail if the --namespace parameter is present
> +    my $no_namespace_parameter = {
> +	unmap => 1,
> +    };
> +
> +    push @$cmd, '--namespace', $scfg->{namespace}
> +	if ($scfg->{namespace} && !$no_namespace_parameter->{$op});
> +
>      push @$cmd, '-c', $cmd_option->{ceph_conf} if ($cmd_option->{ceph_conf});
>      push @$cmd, '-m', $cmd_option->{mon_host} if ($cmd_option->{mon_host});
>      push @$cmd, '--auth_supported', $cmd_option->{auth_supported} if ($cmd_option->{auth_supported});
> @@ -154,6 +164,7 @@ sub rbd_ls {
>  
>      my $cmd = &$rbd_cmd($scfg, $storeid, 'ls', '-l', '--format', 'json');
>      my $pool =  $scfg->{pool} ? $scfg->{pool} : 'rbd';
> +    $pool .= "/$scfg->{namespace}" if $scfg->{namespace};
>  
>      my $raw = '';
>      my $parser = sub { $raw .= shift };
> @@ -281,6 +292,10 @@ sub properties {
>  	    description => "Pool.",
>  	    type => 'string',
>  	},
> +	namespace=> {
> +	    description => "RBD Namespace.",
> +	    type => 'string',
> +	},
>  	username => {
>  	    description => "RBD Id.",
>  	    type => 'string',
> @@ -302,6 +317,7 @@ sub options {
>  	disable => { optional => 1 },
>  	monhost => { optional => 1},
>  	pool => { optional => 1 },
> +	namespace => { optional => 1 },
>  	username => { optional => 1 },
>  	content => { optional => 1 },
>  	krbd => { optional => 1 },
> @@ -349,9 +365,10 @@ sub path {
>      $name .= '@'.$snapname if $snapname;
>  
>      my $pool =  $scfg->{pool} ? $scfg->{pool} : 'rbd';
> -    return ("/dev/rbd/$pool/$name", $vmid, $vtype) if $scfg->{krbd};
> +    my $namespace = $scfg->{namespace} ? "/$scfg->{namespace}" : "";

same as above, a for perl falsy $ns value "breaks" this.

maybe we could use a `get_pool_ns_path($scfg)` (possible better name possible,
should be relatively short and not too misguiding) sub returning both of above? 

Or actually: maybe even a `get_rbd_path($scfg, $image)` returning
"${pool}${namespace}${image}"

(with $ns omitted/added depending on config)

There's seems to be more use for that one when looking at the changes made here.

> +    return ("/dev/rbd/${pool}${namespace}/${name}", $vmid, $vtype) if $scfg->{krbd};
>  
> -    my $path = "rbd:$pool/$name";
> +    my $path = "rbd:${pool}${namespace}/${name}";
>  
>      $path .= ":conf=$cmd_option->{ceph_conf}" if $cmd_option->{ceph_conf};
>      if (defined($scfg->{monhost})) {
> @@ -370,6 +387,7 @@ sub find_free_diskname {
>      my ($class, $storeid, $scfg, $vmid, $fmt, $add_fmt_suffix) = @_;
>  
>      my $cmd = &$rbd_cmd($scfg, $storeid, 'ls');
> +

unrelated new line added? (albeit this one may improve code readability, so fine for me)

>      my $disk_list = [];
>  
>      my $parser = sub {
> @@ -487,6 +505,7 @@ sub free_image {
>      my ($vtype, $name, $vmid, undef, undef, undef) =
>  	$class->parse_volname($volname);
>  
> +

bogus new lien added?

>      my $snaps = rbd_ls_snap($scfg, $storeid, $name);
>      foreach my $snap (keys %$snaps) {
>  	if ($snaps->{$snap}->{protected}) {
> @@ -511,6 +530,7 @@ sub list_images {
>  
>      $cache->{rbd} = rbd_ls($scfg, $storeid) if !$cache->{rbd};
>      my $pool =  $scfg->{pool} ? $scfg->{pool} : 'rbd';
> +    $pool .= "/$scfg->{namespace}" if $scfg->{namespace};
>  
>      my $res = [];
>  
> @@ -575,7 +595,9 @@ sub deactivate_storage {
>  }
>  
>  my $get_kernel_device_name = sub {
> -    my ($pool, $name) = @_;
> +    my ($pool, $name, $namespace) = @_;
> +
> +    return "/dev/rbd/${pool}/${namespace}/${name}" if $namespace;
>  
>      return "/dev/rbd/$pool/$name";
>  };
> @@ -590,7 +612,7 @@ sub map_volume {
>  
>      my $pool =  $scfg->{pool} ? $scfg->{pool} : 'rbd';
>  
> -    my $kerneldev = $get_kernel_device_name->($pool, $name);
> +    my $kerneldev = $get_kernel_device_name->($pool, $name, $scfg->{namespace});
>  
>      return $kerneldev if -b $kerneldev; # already mapped
>  
> @@ -611,7 +633,7 @@ sub unmap_volume {
>  
>      my $pool =  $scfg->{pool} ? $scfg->{pool} : 'rbd';
>  
> -    my $kerneldev = $get_kernel_device_name->($pool, $name);
> +    my $kerneldev = $get_kernel_device_name->($pool, $name, $scfg->{namespace});
>  
>      if (-b $kerneldev) {
>  	my $cmd = &$rbd_cmd($scfg, $storeid, 'unmap', $kerneldev);
>