Add device passthrough

[pve-container.git] / src / lxc-pve-prestart-hook

diff --git a/src/lxc-pve-prestart-hook b/src/lxc-pve-prestart-hook
index 936d0bfe8ee7f0bffdbbb107cb00f16afe3289fe..438ffad8c6b251bbdc90ed05996a787721589d6c 100755 (executable)
--- a/src/lxc-pve-prestart-hook
+++ b/src/lxc-pve-prestart-hook
@@ -6,6 +6,7 @@ use strict;
 use warnings;
 
 use Fcntl qw(O_DIRECTORY :mode);
+use File::Basename;
 use File::Path;
 use POSIX;
 
@@ -58,11 +59,13 @@ PVE::LXC::Tools::lxc_hook('pre-start', 'lxc', sub {
     # Delete any leftover reboot-trigger file
     unlink("/var/lib/lxc/$vmid/reboot");
 
-    my $devlist_file = "/var/lib/lxc/$vmid/devices";
-    unlink $devlist_file;
+    # Delete the old device list file
+    # in case it was left over from a previous version of pve-container.
+    unlink("/var/lib/lxc/$vmid/devices");
+
     my $devices = [];
 
-    my (undef, $rootuid, $rootgid) = PVE::LXC::parse_id_maps($conf);
+    my ($id_map, $rootuid, $rootgid) = PVE::LXC::parse_id_maps($conf);
 
     # Unmount first when the user mounted the container with "pct mount".
     eval {
@@ -118,6 +121,49 @@ PVE::LXC::Tools::lxc_hook('pre-start', 'lxc', sub {
 
     PVE::LXC::Config->foreach_volume($conf, $setup_mountpoint);
 
+    # Device passthrough
+    my $passthrough_devices = [];
+
+    my $passthrough_dir = "/var/lib/lxc/$vmid/passthrough";
+    File::Path::make_path($passthrough_dir);
+    PVE::Tools::mount("none", $passthrough_dir, "tmpfs", 0, "size=8k")
+        or die ("Could not mount tmpfs for device passthrough at $passthrough_dir: $!");
+
+    my $setup_passthrough_device = sub {
+       my ($key, $device) = @_;
+
+       my $absolute_path = $device->{path};
+       my ($mode, $rdev) = (stat($absolute_path))[2, 6];
+
+       die "Could not get mode or device ID of $absolute_path\n"
+           if (!defined($mode) || !defined($rdev));
+
+       my $passthrough_device_path = $passthrough_dir . $absolute_path;
+       File::Path::make_path(dirname($passthrough_device_path));
+       PVE::Tools::mknod($passthrough_device_path, $mode, $rdev)
+           or die("failed to mknod $passthrough_device_path: $!\n");
+
+       # Use chmod because umask could mess with the access mode on mknod
+       my $passthrough_mode = 0660;
+       $passthrough_mode = oct($device->{mode}) if defined($device->{mode});
+       chmod $passthrough_mode, $passthrough_device_path
+           or die "failed to chmod $passthrough_mode $passthrough_device_path: $!\n";
+
+       # Set uid and gid of the device node
+       my $uid = 0;
+       my $gid = 0;
+       $uid = $device->{uid} if defined($device->{uid});
+       $gid = $device->{gid} if defined($device->{gid});
+       $uid = PVE::LXC::map_ct_uid_to_host($uid, $id_map);
+       $gid = PVE::LXC::map_ct_gid_to_host($gid, $id_map);
+       chown $uid, $gid, $passthrough_device_path
+           or die("failed to chown $uid:$gid $passthrough_device_path: $!\n");
+
+       push @$passthrough_devices, [$absolute_path, $mode, $rdev];
+    };
+
+    PVE::LXC::Config->foreach_passthrough_device($conf, $setup_passthrough_device);
+
     my $lxc_setup = PVE::LXC::Setup->new($conf, $rootdir);
     $lxc_setup->pre_start_hook();
 
@@ -138,7 +184,19 @@ PVE::LXC::Tools::lxc_hook('pre-start', 'lxc', sub {
            my $minor = PVE::Tools::dev_t_minor($rdev);
            $devlist .= "b:$major:$minor:$dev\n";
        }
-       PVE::Tools::file_set_contents($devlist_file, $devlist);
+       PVE::Tools::file_set_contents("/var/lib/lxc/$vmid/passthrough/mounts", $devlist);
+    }
+
+    if (@$passthrough_devices) {
+       my $devlist = '';
+       for my $dev (@$passthrough_devices) {
+           my ($path, $mode, $rdev) = @$dev;
+           my $major = PVE::Tools::dev_t_major($rdev);
+           my $minor = PVE::Tools::dev_t_minor($rdev);
+           my $device_type_char = S_ISBLK($mode) ? 'b' : 'c';
+           $devlist .= "$device_type_char:$major:$minor:$path\n";
+       }
+       PVE::Tools::file_set_contents("/var/lib/lxc/$vmid/passthrough/devices", $devlist);
     }
 });