On Thu, Nov 16, 2023 at 12:50:44PM +0100, Filip Schauer wrote:
Add a dev[n] argument to the container config to pass devices through to
a container. A device can be passed by its path. Additionally the access
mode, uid and gid can be specified through their respective properties.
Signed-off-by: Filip Schauer <f.scha...@proxmox.com>
---
Changes since v4:
* Rename device lists to "mounts" and "devices" respectively
and move them into the tmpfs mounted to the passthrough directory
* Add detailed $! error messages
* Enforce stricter config formatting on passthrough devices
* Combine regex in verify_lxc_dev_string and describe what it does in
a comment
* Remove unnecessary int() in map_ct_id_to_host since Perl automatically
parses a string as a number when compared to a number
* Cosmetic changes (foreach --> for, unless --> if)
src/PVE/LXC.pm | 53 +++++++++++++++++++++++-
src/PVE/LXC/Config.pm | 84 +++++++++++++++++++++++++++++++++++++++
src/PVE/LXC/Tools.pm | 23 ++++++++---
src/lxc-pve-autodev-hook | 20 ++++++++--
src/lxc-pve-prestart-hook | 62 +++++++++++++++++++++++++++--
5 files changed, 229 insertions(+), 13 deletions(-)
diff --git a/src/PVE/LXC.pm b/src/PVE/LXC.pm
index 8f53b53..98eb909 100644
--- a/src/PVE/LXC.pm
+++ b/src/PVE/LXC.pm
@@ -5,7 +5,7 @@ use warnings;
use Cwd qw();
use Errno qw(ELOOP ENOTDIR EROFS ECONNREFUSED EEXIST);
-use Fcntl qw(O_RDONLY O_WRONLY O_NOFOLLOW O_DIRECTORY);
+use Fcntl qw(O_RDONLY O_WRONLY O_NOFOLLOW O_DIRECTORY :mode);
use File::Path;
use File::Spec;
use IO::Poll qw(POLLIN POLLHUP);
@@ -639,6 +639,27 @@ sub update_lxc_config {
$raw .= "lxc.mount.auto = sys:mixed\n";
}
+ PVE::LXC::Config->foreach_passthrough_device($conf, sub {
+ my ($key, $device) = @_;
+
+ die "Path is not defined for passthrough device $key"
+ unless (defined($device->{path}));
+
+ my $absolute_path = $device->{path};
+ my ($mode, $rdev) = (stat($absolute_path))[2, 6];
+
+ die "Device $absolute_path does not exist\n"
+ if (!defined($mode) || !defined($rdev));
^ The above is only true for ENOENT, either check it explicitly or use
something like "Error accessing device $absolute_path: $!\n".
+
+ die "$absolute_path is not a device\n"
+ if (!S_ISBLK($mode) && !S_ISCHR($mode));
+
+ 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';
+ $raw .= "lxc.cgroup2.devices.allow = $device_type_char $major:$minor
rw\n";
+ });
+
# WARNING: DO NOT REMOVE this without making sure that loop device nodes
# cannot be exposed to the container with r/w access (cgroup perms).
# When this is enabled mounts will still remain in the monitor's namespace
diff --git a/src/PVE/LXC/Config.pm b/src/PVE/LXC/Config.pm
index 56e1f10..4feae20 100644
--- a/src/PVE/LXC/Config.pm
+++ b/src/PVE/LXC/Config.pm
@@ -1255,6 +1313,20 @@ sub parse_volume {
return;
}
+sub parse_device {
+ my ($class, $device_string, $noerr) = @_;
+
+ my $res = eval { PVE::JSONSchema::parse_property_string($dev_desc,
$device_string) };
+ if ($@) {
+ return undef if $noerr;
+ die $@;
+ }
+
+ die "Path has to be defined" if (!$noerr && !defined($res->{path}));
^ an error with $noerr should still return `undef` - here we'd fall back
to `return $res` on error with $noerr currently, follow the same pattern
as above
+
+ return $res;
+}
+
sub print_volume {
my ($class, $key, $volume) = @_;
diff --git a/src/lxc-pve-autodev-hook b/src/lxc-pve-autodev-hook
index 3c45949..e860fef 100755
--- a/src/lxc-pve-autodev-hook
+++ b/src/lxc-pve-autodev-hook
@@ -3,18 +3,32 @@
use strict;
use warnings;
-use File::Path;
+use Fcntl qw(S_IFREG);
use File::Basename;
+use File::Path;
use PVE::LXC::Tools;
-use PVE::Tools;
+use PVE::Tools qw(MS_BIND);
PVE::LXC::Tools::lxc_hook('autodev', 'lxc', sub {
my ($vmid, $vars, undef, undef) = @_;
my $root = $vars->{ROOTFS_MOUNT};
- PVE::LXC::Tools::for_current_devices($vmid, sub {
+ PVE::LXC::Tools::for_current_passthrough_devices($vmid, sub {
+ my ($type, $major, $minor, $dev) = @_;
+
+ my $rel_devpath = "/dev/$dev";
+ my $rel_dir = dirname($rel_devpath);
+ File::Path::mkpath("$root/$rel_dir");
+ PVE::Tools::mknod("$root/dev/$dev", S_IFREG, 0)
+ or die("Could not mknod $root/dev/$dev: $!\n");
+
+ PVE::Tools::mount("/var/lib/lxc/$vmid/passthrough/dev/$dev",
"$root/dev/$dev", 0, MS_BIND, 0)
+ or die("Bind mount of device $dev into container failed: $!\n");
+ });
+
+ PVE::LXC::Tools::for_current_passthrough_mounts($vmid, sub {
my ($type, $major, $minor, $dev) = @_;
my $rel_devpath = "/dev/$dev";
diff --git a/src/lxc-pve-prestart-hook b/src/lxc-pve-prestart-hook
index 936d0bf..f0cc08d 100755
--- 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 +59,9 @@ 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";
^ It's now technically possible for a startup during a package upgrade
to have issues if we move this since in *theory* the prestart hook could
run with the old package code and the autodev hook with the new package.
Since the pre-start hook unlinks the file, we *could* potentially
fallback to that path in the autodev hook to catch this case...
But then we should keep `unlink`ing on the old path for a while to make
sure we don't fall back to an old leftover file.
- unlink $devlist_file;
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 {
