[PATCH qemu-server 2/6] qm cli: add blockextend

[Alexandre Derumier]

Increase the underlay storage size to an higher value than current
max offset or 1 chunk bigger we max write offset is 0

Signed-off-by: Alexandre Derumier <alexandre.derumier at groupe-cyllene.com>
---
 PVE/CLI/qm.pm     | 31 ++++++++++++++++++++++++++++
 PVE/QemuServer.pm | 52 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 83 insertions(+)

diff --git a/PVE/CLI/qm.pm b/PVE/CLI/qm.pm
index d3dbf7b..1410ad5 100755
--- a/PVE/CLI/qm.pm
+++ b/PVE/CLI/qm.pm
@@ -608,6 +608,36 @@ __PACKAGE__->register_method ({
 	return;
     }});
 
+__PACKAGE__->register_method({
+    name => 'blockextend',
+    path => 'blockextend',
+    method => 'POST',
+    protected => 1,
+    description => "Extend underlay storage to higher value than write threshold.",
+    parameters => {
+	additionalProperties => 0,
+	properties => {
+	    node => get_standard_option('pve-node'),
+	    vmid => get_standard_option('pve-vmid', {
+		    completion => \&PVE::QemuServer::complete_vmid_running }),
+	    disk => {
+		type => 'string',
+		description => 'underlay blocknodeid or drive',
+	    },
+	},
+    },
+    returns => { type => 'null', },
+    code => sub {
+	my ($param) = @_;
+
+	my $vmid = PVE::Tools::extract_param($param, 'vmid');
+	my $disk = PVE::Tools::extract_param($param, 'disk');
+	PVE::QemuServer::block_extend($vmid, $disk);
+
+	return;
+    }
+});
+
 __PACKAGE__->register_method ({
     name => 'terminal',
     path => 'terminal',
@@ -1171,6 +1201,7 @@ our $cmddef = {
 	rescan => [ __PACKAGE__, 'rescan', []],
 	resize => [ "PVE::API2::Qemu", 'resize_vm', ['vmid', 'disk', 'size'], { %node } ],
 	unlink => [ "PVE::API2::Qemu", 'unlink', ['vmid'], { %node } ],
+	blockextend => [ __PACKAGE__, 'blockextend', ['vmid', 'disk'], { %node }],
     },
 
     monitor  => [ __PACKAGE__, 'monitor', ['vmid']],
diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
index 3acb32e..fb67ac9 100644
--- a/PVE/QemuServer.pm
+++ b/PVE/QemuServer.pm
@@ -8926,4 +8926,56 @@ sub set_disks_write_threshold {
     });
 }
 
+sub lock_blockextend {
+    my ($vmid, $timeout, $sub) = @_;
+
+    my $filename = "/var/lock/qemu-server/blockextend-$vmid.lck";
+
+    my $res = PVE::Tools::lock_file($filename, $timeout, $sub);
+    die $@ if $@;
+
+    return $res;
+}
+
+sub block_extend {
+    my ($vmid, $disk) = @_;
+
+    return if !PVE::QemuServer::check_running($vmid);
+
+    my $storecfg = PVE::Storage::config();
+
+    my $blockstats = mon_cmd($vmid, "query-blockstats");
+    $blockstats = { map { $_->{device} => $_ } $blockstats->@* };
+
+    lock_blockextend($vmid, 60, sub {
+
+	# return if we do not have the config anymore
+	return if !-f PVE::QemuConfig->config_file($vmid);
+
+	my $conf = PVE::QemuConfig->load_config($vmid);
+
+	my $blockinfo = get_block_info($vmid, $disk, $blockstats);
+	my $deviceid = $blockinfo->{deviceid};
+	my $drive = PVE::QemuServer::parse_drive($deviceid, $conf->{$deviceid});
+	my $volid = $drive->{file};
+
+	die "can't find volid" if !$volid;
+	my ($sid, $volname) = PVE::Storage::parse_volume_id($volid, 1);
+	die "can't find sid" if !$sid;
+	my $scfg = PVE::Storage::storage_config($storecfg, $sid);
+
+	my $size = PVE::Storage::volume_size_info($storecfg, $volid, 5);
+	my $chunksize = $scfg->{chunksize} // 1024 * 1024 * 1024;
+	my $newsize = $size + $chunksize;
+
+	#if write are really fast, wr_highest_offset could be already higher than the increment
+	if ($blockinfo->{wr_highest_offset} > $newsize) {
+	    $newsize = $blockinfo->{wr_highest_offset} + $chunksize;
+	}
+
+	PVE::Storage::volume_underlay_resize($storecfg, $volid, $newsize);
+	my $threshold = compute_write_threshold($newsize);
+	qemu_block_set_write_threshold($vmid, $blockinfo->{blocknodeid}, $threshold);
+    });
+}
 1;
-- 
2.39.2