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mirror of git://git.proxmox.com/git/pve-guest-common.git synced 2025-01-14 19:24:18 +03:00
pve-guest-common/PVE/AbstractConfig.pm
2017-06-13 09:17:50 +02:00

685 lines
17 KiB
Perl

package PVE::AbstractConfig;
use strict;
use warnings;
use PVE::Tools qw(lock_file lock_file_full);
use PVE::INotify;
use PVE::Cluster;
use PVE::Storage;
use PVE::ReplicationConfig;
use PVE::Replication;
my $nodename = PVE::INotify::nodename();
# Printable string, currently either "VM" or "CT"
sub guest_type {
my ($class) = @_;
die "abstract method - implement me ";
}
sub __config_max_unused_disks {
my ($class) = @_;
die "implement me - abstract method\n";
}
# Path to the flock file for this VM/CT
sub config_file_lock {
my ($class, $vmid) = @_;
die "abstract method - implement me";
}
# Relative config file path for this VM/CT in CFS
sub cfs_config_path {
my ($class, $vmid, $node) = @_;
die "abstract method - implement me";
}
# Absolute config file path for this VM/CT
sub config_file {
my ($class, $vmid, $node) = @_;
my $cfspath = $class->cfs_config_path($vmid, $node);
return "/etc/pve/$cfspath";
}
# Read and parse config file for this VM/CT
sub load_config {
my ($class, $vmid, $node) = @_;
$node = $nodename if !$node;
my $cfspath = $class->cfs_config_path($vmid, $node);
my $conf = PVE::Cluster::cfs_read_file($cfspath);
die "Configuration file '$cfspath' does not exist\n"
if !defined($conf);
return $conf;
}
# Generate and write config file for this VM/CT
sub write_config {
my ($class, $vmid, $conf) = @_;
my $cfspath = $class->cfs_config_path($vmid);
PVE::Cluster::cfs_write_file($cfspath, $conf);
}
# Lock config file using flock, run $code with @param, unlock config file.
# $timeout is the maximum time to aquire the flock
sub lock_config_full {
my ($class, $vmid, $timeout, $code, @param) = @_;
my $filename = $class->config_file_lock($vmid);
my $res = lock_file($filename, $timeout, $code, @param);
die $@ if $@;
return $res;
}
# Lock config file using flock, run $code with @param, unlock config file.
# $timeout is the maximum time to aquire the flock
# $shared eq 1 creates a non-exclusive ("read") flock
sub lock_config_mode {
my ($class, $vmid, $timeout, $shared, $code, @param) = @_;
my $filename = $class->config_file_lock($vmid);
my $res = lock_file_full($filename, $timeout, $shared, $code, @param);
die $@ if $@;
return $res;
}
# Lock config file using flock, run $code with @param, unlock config file.
sub lock_config {
my ($class, $vmid, $code, @param) = @_;
return $class->lock_config_full($vmid, 10, $code, @param);
}
# Checks whether the config is locked with the lock parameter
sub check_lock {
my ($class, $conf) = @_;
die $class->guest_type()." is locked ($conf->{lock})\n" if $conf->{lock};
}
# Returns whether the config is locked with the lock parameter, also checks
# whether the lock value is correct if the optional $lock is set.
sub has_lock {
my ($class, $conf, $lock) = @_;
return $conf->{lock} && (!defined($lock) || $lock eq $conf->{lock});
}
# Sets the lock parameter for this VM/CT's config to $lock.
sub set_lock {
my ($class, $vmid, $lock) = @_;
my $conf;
$class->lock_config($vmid, sub {
$conf = $class->load_config($vmid);
$class->check_lock($conf);
$conf->{lock} = $lock;
$class->write_config($vmid, $conf);
});
return $conf;
}
# Removes the lock parameter for this VM/CT's config, also checks whether
# the lock value is correct if the optional $lock is set.
sub remove_lock {
my ($class, $vmid, $lock) = @_;
$class->lock_config($vmid, sub {
my $conf = $class->load_config($vmid);
if (!$conf->{lock}) {
my $lockstring = defined($lock) ? "'$lock' " : "any";
die "no lock found trying to remove $lockstring lock\n";
} elsif (defined($lock) && $conf->{lock} ne $lock) {
die "found lock '$conf->{lock}' trying to remove '$lock' lock\n";
}
delete $conf->{lock};
$class->write_config($vmid, $conf);
});
}
# Checks whether protection mode is enabled for this VM/CT.
sub check_protection {
my ($class, $conf, $err_msg) = @_;
if ($conf->{protection}) {
die "$err_msg - protection mode enabled\n";
}
}
# Adds an unused volume to $config, if possible.
sub add_unused_volume {
my ($class, $config, $volid) = @_;
my $key;
for (my $ind = $class->__config_max_unused_disks() - 1; $ind >= 0; $ind--) {
my $test = "unused$ind";
if (my $vid = $config->{$test}) {
return if $vid eq $volid; # do not add duplicates
} else {
$key = $test;
}
}
die "Too many unused volumes - please delete them first.\n" if !$key;
$config->{$key} = $volid;
return $key;
}
# Returns whether the template parameter is set in $conf.
sub is_template {
my ($class, $conf) = @_;
return 1 if defined $conf->{template} && $conf->{template} == 1;
}
# Checks whether $feature is availabe for the referenced volumes in $conf.
# Note: depending on the parameters, some volumes may be skipped!
sub has_feature {
my ($class, $feature, $conf, $storecfg, $snapname, $running, $backup_only) = @_;
die "implement me - abstract method\n";
}
# get all replicatable volume (hash $res->{$volid} = 1)
# $cleanup: for cleanup - simply ignores volumes without replicate feature
# $norerr: never raise exceptions - return undef instead
sub get_replicatable_volumes {
my ($class, $storecfg, $vmid, $conf, $cleanup, $noerr) = @_;
die "implement me - abstract method\n";
}
# Internal snapshots
# NOTE: Snapshot create/delete involves several non-atomic
# actions, and can take a long time.
# So we try to avoid locking the file and use the 'lock' variable
# inside the config file instead.
# Save the vmstate (RAM).
sub __snapshot_save_vmstate {
my ($class, $vmid, $conf, $snapname, $storecfg) = @_;
die "implement me - abstract method\n";
}
# Check whether the VM/CT is running.
sub __snapshot_check_running {
my ($class, $vmid) = @_;
die "implement me - abstract method\n";
}
# Check whether we need to freeze the VM/CT
sub __snapshot_check_freeze_needed {
my ($sself, $vmid, $config, $save_vmstate) = @_;
die "implement me - abstract method\n";
}
# Freeze or unfreeze the VM/CT.
sub __snapshot_freeze {
my ($class, $vmid, $unfreeze) = @_;
die "abstract method - implement me\n";
}
# Code run before and after creating all the volume snapshots
# base: noop
sub __snapshot_create_vol_snapshots_hook {
my ($class, $vmid, $snap, $running, $hook) = @_;
return;
}
# Create the volume snapshots for the VM/CT.
sub __snapshot_create_vol_snapshot {
my ($class, $vmid, $vs, $volume, $snapname) = @_;
die "abstract method - implement me\n";
}
# Remove a drive from the snapshot config.
sub __snapshot_delete_remove_drive {
my ($class, $snap, $drive) = @_;
die "abstract method - implement me\n";
}
# Delete the vmstate file/drive
sub __snapshot_delete_vmstate_file {
my ($class, $snap, $force) = @_;
die "abstract method - implement me\n";
}
# Delete a volume snapshot
sub __snapshot_delete_vol_snapshot {
my ($class, $vmid, $vs, $volume, $snapname) = @_;
die "abstract method - implement me\n";
}
# Checks whether a volume snapshot is possible for this volume.
sub __snapshot_rollback_vol_possible {
my ($class, $volume, $snapname) = @_;
die "abstract method - implement me\n";
}
# Rolls back this volume.
sub __snapshot_rollback_vol_rollback {
my ($class, $volume, $snapname) = @_;
die "abstract method - implement me\n";
}
# Stops the VM/CT for a rollback.
sub __snapshot_rollback_vm_stop {
my ($class, $vmid) = @_;
die "abstract method - implement me\n";
}
# Start the VM/CT after a rollback with restored vmstate.
sub __snapshot_rollback_vm_start {
my ($class, $vmid, $vmstate, $forcemachine);
die "abstract method - implement me\n";
}
# Get list of volume IDs which are referenced in $conf, but not in $snap.
sub __snapshot_rollback_get_unused {
my ($class, $conf, $snap) = @_;
die "abstract method - implement me\n";
}
# Iterate over all configured volumes, calling $func for each key/value pair.
sub __snapshot_foreach_volume {
my ($class, $conf, $func) = @_;
die "abstract method - implement me\n";
}
# Copy the current config $source to the snapshot config $dest
sub __snapshot_copy_config {
my ($class, $source, $dest) = @_;
foreach my $k (keys %$source) {
next if $k eq 'snapshots';
next if $k eq 'snapstate';
next if $k eq 'snaptime';
next if $k eq 'vmstate';
next if $k eq 'lock';
next if $k eq 'digest';
next if $k eq 'description';
next if $k =~ m/^unused\d+$/;
$dest->{$k} = $source->{$k};
}
};
# Apply the snapshot config $snap to the config $conf (rollback)
sub __snapshot_apply_config {
my ($class, $conf, $snap) = @_;
# copy snapshot list
my $newconf = {
snapshots => $conf->{snapshots},
};
# keep description and list of unused disks
foreach my $k (keys %$conf) {
next if !($k =~ m/^unused\d+$/ || $k eq 'description');
$newconf->{$k} = $conf->{$k};
}
$class->__snapshot_copy_config($snap, $newconf);
return $newconf;
}
# Prepares the configuration for snapshotting.
sub __snapshot_prepare {
my ($class, $vmid, $snapname, $save_vmstate, $comment) = @_;
my $snap;
my $updatefn = sub {
my $conf = $class->load_config($vmid);
die "you can't take a snapshot if it's a template\n"
if $class->is_template($conf);
$class->check_lock($conf);
$conf->{lock} = 'snapshot';
die "snapshot name '$snapname' already used\n"
if defined($conf->{snapshots}->{$snapname});
my $storecfg = PVE::Storage::config();
die "snapshot feature is not available\n"
if !$class->has_feature('snapshot', $conf, $storecfg, undef, undef, $snapname eq 'vzdump');
$snap = $conf->{snapshots}->{$snapname} = {};
if ($save_vmstate && $class->__snapshot_check_running($vmid)) {
$class->__snapshot_save_vmstate($vmid, $conf, $snapname, $storecfg);
}
$class->__snapshot_copy_config($conf, $snap);
$snap->{snapstate} = "prepare";
$snap->{snaptime} = time();
$snap->{description} = $comment if $comment;
$class->write_config($vmid, $conf);
};
$class->lock_config($vmid, $updatefn);
return $snap;
}
# Commits the configuration after snapshotting.
sub __snapshot_commit {
my ($class, $vmid, $snapname) = @_;
my $updatefn = sub {
my $conf = $class->load_config($vmid);
die "missing snapshot lock\n"
if !($conf->{lock} && $conf->{lock} eq 'snapshot');
my $snap = $conf->{snapshots}->{$snapname};
die "snapshot '$snapname' does not exist\n" if !defined($snap);
die "wrong snapshot state\n"
if !($snap->{snapstate} && $snap->{snapstate} eq "prepare");
delete $snap->{snapstate};
delete $conf->{lock};
$conf->{parent} = $snapname;
$class->write_config($vmid, $conf);
};
$class->lock_config($vmid, $updatefn);
}
# Creates a snapshot for the VM/CT.
sub snapshot_create {
my ($class, $vmid, $snapname, $save_vmstate, $comment) = @_;
my $snap = $class->__snapshot_prepare($vmid, $snapname, $save_vmstate, $comment);
$save_vmstate = 0 if !$snap->{vmstate};
my $conf = $class->load_config($vmid);
my ($running, $freezefs) = $class->__snapshot_check_freeze_needed($vmid, $conf, $snap->{vmstate});
my $drivehash = {};
eval {
if ($freezefs) {
$class->__snapshot_freeze($vmid, 0);
}
$class->__snapshot_create_vol_snapshots_hook($vmid, $snap, $running, "before");
$class->__snapshot_foreach_volume($snap, sub {
my ($vs, $volume) = @_;
$class->__snapshot_create_vol_snapshot($vmid, $vs, $volume, $snapname);
$drivehash->{$vs} = 1;
});
};
my $err = $@;
if ($running) {
$class->__snapshot_create_vol_snapshots_hook($vmid, $snap, $running, "after");
if ($freezefs) {
$class->__snapshot_freeze($vmid, 1);
}
$class->__snapshot_create_vol_snapshots_hook($vmid, $snap, $running, "after-unfreeze");
}
if ($err) {
warn "snapshot create failed: starting cleanup\n";
eval { $class->snapshot_delete($vmid, $snapname, 1, $drivehash); };
warn "$@" if $@;
die "$err\n";
}
$class->__snapshot_commit($vmid, $snapname);
}
# Deletes a snapshot.
# Note: $drivehash is only set when called from snapshot_create.
sub snapshot_delete {
my ($class, $vmid, $snapname, $force, $drivehash) = @_;
my $prepare = 1;
my $snap;
my $unused = [];
$class->set_lock($vmid, 'snapshot-delete')
if (!$drivehash); # doesn't already have a 'snapshot' lock
my $unlink_parent = sub {
my ($confref, $new_parent) = @_;
if ($confref->{parent} && $confref->{parent} eq $snapname) {
if ($new_parent) {
$confref->{parent} = $new_parent;
} else {
delete $confref->{parent};
}
}
};
my $remove_drive = sub {
my ($drive) = @_;
my $conf = $class->load_config($vmid);
$snap = $conf->{snapshots}->{$snapname};
die "snapshot '$snapname' does not exist\n" if !defined($snap);
$class->__snapshot_delete_remove_drive($snap, $drive);
$class->write_config($vmid, $conf);
};
#prepare
$class->lock_config($vmid, sub {
my $conf = $class->load_config($vmid);
die "you can't delete a snapshot if vm is a template\n"
if $class->is_template($conf);
$snap = $conf->{snapshots}->{$snapname};
die "snapshot '$snapname' does not exist\n" if !defined($snap);
$snap->{snapstate} = 'delete';
$class->write_config($vmid, $conf);
});
# now remove vmstate file
if ($snap->{vmstate}) {
$class->__snapshot_delete_vmstate_file($snap, $force);
# save changes (remove vmstate from snapshot)
$class->lock_config($vmid, $remove_drive, 'vmstate') if !$force;
};
# now remove all volume snapshots
$class->__snapshot_foreach_volume($snap, sub {
my ($vs, $volume) = @_;
return if $snapname eq 'vzdump' && $vs ne 'rootfs' && !$volume->{backup};
if (!$drivehash || $drivehash->{$vs}) {
eval { $class->__snapshot_delete_vol_snapshot($vmid, $vs, $volume, $snapname, $unused); };
if (my $err = $@) {
die $err if !$force;
warn $err;
}
}
# save changes (remove drive from snapshot)
$class->lock_config($vmid, $remove_drive, $vs) if !$force;
});
# now cleanup config
$class->lock_config($vmid, sub {
my $conf = $class->load_config($vmid);
$snap = $conf->{snapshots}->{$snapname};
die "snapshot '$snapname' does not exist\n" if !defined($snap);
# remove parent refs
&$unlink_parent($conf, $snap->{parent});
foreach my $sn (keys %{$conf->{snapshots}}) {
next if $sn eq $snapname;
&$unlink_parent($conf->{snapshots}->{$sn}, $snap->{parent});
}
delete $conf->{snapshots}->{$snapname};
delete $conf->{lock};
foreach my $volid (@$unused) {
$class->add_unused_volume($conf, $volid);
}
$class->write_config($vmid, $conf);
});
}
# Rolls back to a given snapshot.
sub snapshot_rollback {
my ($class, $vmid, $snapname) = @_;
my $prepare = 1;
my $storecfg = PVE::Storage::config();
my $conf = $class->load_config($vmid);
my $get_snapshot_config = sub {
die "you can't rollback if vm is a template\n" if $class->is_template($conf);
my $res = $conf->{snapshots}->{$snapname};
die "snapshot '$snapname' does not exist\n" if !defined($res);
return $res;
};
my $repl_conf = PVE::ReplicationConfig->new();
if ($repl_conf->check_for_existing_jobs($vmid, 1)) {
# remove all replication snapshots
my $volumes = $class->get_replicatable_volumes($storecfg, $vmid, $conf, 1);
my $sorted_volids = [ sort keys %$volumes ];
# remove all local replication snapshots (jobid => undef)
my $logfunc = sub { my $line = shift; chomp $line; print "$line\n"; };
PVE::Replication::prepare($storecfg, $sorted_volids, undef, 0, undef, $logfunc);
}
my $snap = &$get_snapshot_config();
$class->__snapshot_foreach_volume($snap, sub {
my ($vs, $volume) = @_;
$class->__snapshot_rollback_vol_possible($volume, $snapname);
});
my $updatefn = sub {
$conf = $class->load_config($vmid);
$snap = &$get_snapshot_config();
die "unable to rollback to incomplete snapshot (snapstate = $snap->{snapstate})\n"
if $snap->{snapstate};
if ($prepare) {
$class->check_lock($conf);
$class->__snapshot_rollback_vm_stop($vmid);
}
die "unable to rollback vm $vmid: vm is running\n"
if $class->__snapshot_check_running($vmid);
if ($prepare) {
$conf->{lock} = 'rollback';
} else {
die "got wrong lock\n" if !($conf->{lock} && $conf->{lock} eq 'rollback');
delete $conf->{lock};
}
# machine only relevant for Qemu
my $forcemachine;
if (!$prepare) {
my $unused = $class->__snapshot_rollback_get_unused($conf, $snap);
foreach my $volid (@$unused) {
$class->add_unused_volume($conf, $volid);
}
my $has_machine_config = defined($conf->{machine});
# copy snapshot config to current config
$conf = $class->__snapshot_apply_config($conf, $snap);
$conf->{parent} = $snapname;
# Note: old code did not store 'machine', so we try to be smart
# and guess the snapshot was generated with kvm 1.4 (pc-i440fx-1.4).
$forcemachine = $conf->{machine} || 'pc-i440fx-1.4';
# we remove the 'machine' configuration if not explicitly specified
# in the original config.
delete $conf->{machine} if $snap->{vmstate} && !$has_machine_config;
}
$class->write_config($vmid, $conf);
if (!$prepare && $snap->{vmstate}) {
$class->__snapshot_rollback_vm_start($vmid, $snap->{vmstate}, $forcemachine);
}
};
$class->lock_config($vmid, $updatefn);
$class->__snapshot_foreach_volume($snap, sub {
my ($vs, $volume) = @_;
$class->__snapshot_rollback_vol_rollback($volume, $snapname);
});
$prepare = 0;
$class->lock_config($vmid, $updatefn);
}
1;