[PATCH v2 pve-storage 1/2] add external snasphot support
Alexandre Derumier
alexandre.derumier at groupe-cyllene.com
Mon Sep 30 13:31:51 CEST 2024
Signed-off-by: Alexandre Derumier <alexandre.derumier at groupe-cyllene.com>
---
src/PVE/Storage/DirPlugin.pm | 1 +
src/PVE/Storage/Plugin.pm | 225 +++++++++++++++++++++++++++++++----
2 files changed, 201 insertions(+), 25 deletions(-)
diff --git a/src/PVE/Storage/DirPlugin.pm b/src/PVE/Storage/DirPlugin.pm
index 2efa8d5..2bef673 100644
--- a/src/PVE/Storage/DirPlugin.pm
+++ b/src/PVE/Storage/DirPlugin.pm
@@ -80,6 +80,7 @@ sub options {
is_mountpoint => { optional => 1 },
bwlimit => { optional => 1 },
preallocation => { optional => 1 },
+ snapext => { optional => 1 },
};
}
diff --git a/src/PVE/Storage/Plugin.pm b/src/PVE/Storage/Plugin.pm
index 6444390..5e5197a 100644
--- a/src/PVE/Storage/Plugin.pm
+++ b/src/PVE/Storage/Plugin.pm
@@ -214,6 +214,11 @@ my $defaultData = {
maximum => 65535,
optional => 1,
},
+ 'snapext' => {
+ type => 'boolean',
+ description => 'enable external snapshot.',
+ optional => 1,
+ },
},
};
@@ -695,7 +700,7 @@ sub get_subdir {
}
sub filesystem_path {
- my ($class, $scfg, $volname, $snapname) = @_;
+ my ($class, $scfg, $volname, $snapname, $current_snap) = @_;
my ($vtype, $name, $vmid, undef, undef, $isBase, $format) =
$class->parse_volname($volname);
@@ -703,7 +708,7 @@ sub filesystem_path {
# Note: qcow2/qed has internal snapshot, so path is always
# the same (with or without snapshot => same file).
die "can't snapshot this image format\n"
- if defined($snapname) && $format !~ m/^(qcow2|qed)$/;
+ if defined($snapname) && !$scfg->{snapext} && $format !~ m/^(qcow2|qed)$/;
my $dir = $class->get_subdir($scfg, $vtype);
@@ -711,13 +716,22 @@ sub filesystem_path {
my $path = "$dir/$name";
+ if($scfg->{snapext}) {
+ my $snappath = get_snap_path($path, $snapname);
+ if($snapname) {
+ $path = $snappath;
+ } elsif ($current_snap) {
+ $path = $current_snap->{file};
+ }
+ }
return wantarray ? ($path, $vmid, $vtype) : $path;
}
sub path {
my ($class, $scfg, $volname, $storeid, $snapname) = @_;
- return $class->filesystem_path($scfg, $volname, $snapname);
+ my $current_snapshot = $class->get_current_snapshot($scfg, $storeid, $volname);
+ return $class->filesystem_path($scfg, $volname, $snapname, $current_snapshot);
}
sub create_base {
@@ -1074,13 +1088,31 @@ sub volume_resize {
sub volume_snapshot {
my ($class, $scfg, $storeid, $volname, $snap) = @_;
- die "can't snapshot this image format\n" if $volname !~ m/\.(qcow2|qed)$/;
+ die "can't snapshot this image format\n" if $volname !~ m/\.(raw|qcow2|qed)$/;
- my $path = $class->filesystem_path($scfg, $volname);
+ die "external snapshot need to be enabled to snapshot .raw volumes\n" if !$scfg->{snapext};
- my $cmd = ['/usr/bin/qemu-img', 'snapshot','-c', $snap, $path];
+ if($scfg->{snapext}) {
- run_command($cmd);
+ my $path = $class->path($scfg, $volname, $storeid);
+
+ my $snappath = get_snap_path($path, $snap);
+ my $format = ($class->parse_volname($volname))[6];
+
+ my $cmd = ['/usr/bin/qemu-img', 'create', '-b', $path,
+ '-F', $format, '-f', 'qcow2', $snappath];
+
+ my $options = "extended_l2=on,";
+ $options .= preallocation_cmd_option($scfg, 'qcow2');
+ push @$cmd, '-o', $options;
+ run_command($cmd);
+
+ } else {
+
+ my $path = $class->filesystem_path($scfg, $volname);
+ my $cmd = ['/usr/bin/qemu-img', 'snapshot','-c', $snap, $path];
+ run_command($cmd);
+ }
return undef;
}
@@ -1091,19 +1123,39 @@ sub volume_snapshot {
sub volume_rollback_is_possible {
my ($class, $scfg, $storeid, $volname, $snap, $blockers) = @_;
+ if ($scfg->{snapext}) {
+ #technically, we could manage multibranch, we it need lot more work for snapshot delete
+ my $path = $class->filesystem_path($scfg, $volname);
+ my $snappath = get_snap_path($path, $snap);
+
+ my $snapshots = $class->volume_snapshot_info($scfg, $storeid, $volname);
+ my $currentpath = $snapshots->{current}->{file};
+ return 1 if !-e $snappath || $currentpath eq $snappath;
+
+ die "can't rollback, '$snap' is not most recent snapshot on '$volname'\n";
+ }
+
return 1;
}
sub volume_snapshot_rollback {
my ($class, $scfg, $storeid, $volname, $snap) = @_;
- die "can't rollback snapshot this image format\n" if $volname !~ m/\.(qcow2|qed)$/;
+ die "can't rollback snapshot this image format\n" if $volname !~ m/\.(raw|qcow2|qed)$/;
- my $path = $class->filesystem_path($scfg, $volname);
+ die "external snapshot need to be enabled to rollback snapshot .raw volumes\n" if $volname =~ m/\.(raw)$/ && !$scfg->{snapext};
- my $cmd = ['/usr/bin/qemu-img', 'snapshot','-a', $snap, $path];
+ my $path = $class->filesystem_path($scfg, $volname);
- run_command($cmd);
+ if ($scfg->{snapext}) {
+ #simply delete the current snapshot and recreate it
+ my $snappath = get_snap_path($path, $snap);
+ unlink($snappath);
+ $class->volume_snapshot($scfg, $storeid, $volname, $snap);
+ } else {
+ my $cmd = ['/usr/bin/qemu-img', 'snapshot','-a', $snap, $path];
+ run_command($cmd);
+ }
return undef;
}
@@ -1111,17 +1163,50 @@ sub volume_snapshot_rollback {
sub volume_snapshot_delete {
my ($class, $scfg, $storeid, $volname, $snap, $running) = @_;
- die "can't delete snapshot for this image format\n" if $volname !~ m/\.(qcow2|qed)$/;
+ die "can't delete snapshot for this image format\n" if $volname !~ m/\.(raw|qcow2|qed)$/;
+
+ die "external snapshot need to be enabled to delete snapshot of .raw volumes\n" if !$scfg->{snapext};
return 1 if $running;
- my $path = $class->filesystem_path($scfg, $volname);
+ my $cmd = "";
+ if ($scfg->{snapext}) {
+
+ my $snapshots = $class->volume_snapshot_info($scfg, $storeid, $volname);
+ my $snappath = $snapshots->{$snap}->{file};
+ return if !-e $snappath; #already deleted ?
+
+ my $parentsnap = $snapshots->{$snap}->{parent};
+ my $childsnap = $snapshots->{$snap}->{child};
+ die "error: can't find a parent for this snapshot" if !$parentsnap;
- $class->deactivate_volume($storeid, $scfg, $volname, $snap, {});
+ my $parentpath = $snapshots->{$parentsnap}->{file};
+ my $parentformat = $snapshots->{$parentsnap}->{'format'} if $parentsnap;
+ my $childpath = $snapshots->{$childsnap}->{file} if $childsnap;
+ my $childformat = $snapshots->{$childsnap}->{'format'} if $childsnap;
- my $cmd = ['/usr/bin/qemu-img', 'snapshot','-d', $snap, $path];
+ print "merge snapshot $snap to $parentsnap\n";
+ $cmd = ['/usr/bin/qemu-img', 'commit', $snappath];
+ run_command($cmd);
+
+ #if we delete an intermediate snapshot, we need to link upper snapshot to base snapshot
+ if($childpath && -e $childpath) {
+ die "missing parentsnap snapshot to rebase child $childpath\n" if !$parentpath;
+ print "link $childsnap to $parentsnap\n";
+ $cmd = ['/usr/bin/qemu-img', 'rebase', '-u', '-b', $parentpath, '-F', $parentformat, '-f', $childformat, $childpath];
+ run_command($cmd);
+ }
+
+ #delete the snapshot
+ unlink($snappath);
+ } else {
+ my $path = $class->filesystem_path($scfg, $volname);
- run_command($cmd);
+ $class->deactivate_volume($storeid, $scfg, $volname, $snap, {});
+
+ $cmd = ['/usr/bin/qemu-img', 'snapshot','-d', $snap, $path];
+ run_command($cmd);
+ }
return undef;
}
@@ -1140,10 +1225,6 @@ sub volume_has_feature {
my ($class, $scfg, $feature, $storeid, $volname, $snapname, $running, $opts) = @_;
my $features = {
- snapshot => {
- current => { qcow2 => 1 },
- snap => { qcow2 => 1 },
- },
clone => {
base => { qcow2 => 1, raw => 1, vmdk => 1 },
},
@@ -1159,11 +1240,23 @@ sub volume_has_feature {
base => { qcow2 => 1, raw => 1, vmdk => 1 },
current => { qcow2 => 1, raw => 1, vmdk => 1 },
},
- rename => {
- current => {qcow2 => 1, raw => 1, vmdk => 1},
- },
+ 'rename' => {
+ current => { qcow2 => 1, raw => 1, vmdk => 1},
+ }
};
+ if ($scfg->{snapext}) {
+ $features->{snapshot} = {
+ current => { raw => 1, qcow2 => 1 },
+ snap => { raw => 1, qcow2 => 1 },
+ }
+ } else {
+ $features->{snapshot} = {
+ current => { qcow2 => 1 },
+ snap => { qcow2 => 1 },
+ };
+ }
+
if ($feature eq 'clone') {
if (
defined($opts->{valid_target_formats})
@@ -1222,7 +1315,9 @@ sub list_images {
}
if ($vollist) {
- my $found = grep { $_ eq $volid } @$vollist;
+ my $search_volid = $volid;
+ $search_volid =~ s/-snap-.*\./\./;
+ my $found = grep { $_ eq $search_volid } @$vollist;
next if !$found;
}
@@ -1380,7 +1475,53 @@ sub status {
sub volume_snapshot_info {
my ($class, $scfg, $storeid, $volname) = @_;
- die "volume_snapshot_info is not implemented for $class";
+ die "volume_snapshot_info is not implemented for $class" if !$scfg->{snapext};
+
+ my $path = $class->filesystem_path($scfg, $volname);
+
+ my ($vtype, $name, $vmid, $basename, $basevmid, $isBase, $format) = $class->parse_volname($volname);
+
+ my $basevolname = $volname;
+ $basevolname =~ s/\.(raw|qcow2)$//;
+
+ my $snapshots = $class->list_images($storeid, $scfg, $vmid);
+ my $info = {};
+ for my $snap (@$snapshots) {
+
+ my $volid = $snap->{volid};
+ next if ($volid !~ m/$basevolname/);
+
+ my (undef, $snapvolname) = parse_volume_id($volid);
+ my $snapname = get_snapname_from_path($volid);
+ my $snapfile = $class->filesystem_path($scfg, $snapvolname, $snapname);
+ $snapname = 'base' if !$snapname;
+
+ my $format = $snap->{'format'};
+ my $parentfile = $snap->{parent};
+ my $parentname = get_snapname_from_path($parentfile) if $parentfile;
+ $parentname = 'base' if !$parentname && $parentfile;
+
+ $info->{$snapname}->{file} = $snapfile;
+ $info->{$snapname}->{volid} = $volid;
+ $info->{$snapname}->{'format'} = $format;
+ $info->{$snapname}->{parent} = $parentname if $parentname;
+ $info->{$parentname}->{child} = $snapname if $parentname;
+ }
+
+ my $current = undef;
+ for my $id (keys %$info) {
+ my $snap = $info->{$id};
+ die "error: snap $id: you can't have multiple current snapshot: current:$current\n" if !$snap->{child} && $current;
+ $current = $id if !$snap->{child};
+ }
+
+ if ($current) {
+ $info->{current}->{file} = $info->{$current}->{file};
+ $info->{current}->{'format'} = $info->{$current}->{'format'};
+ $info->{current}->{parent} = $info->{$current}->{parent};
+ }
+
+ return $info;
}
sub activate_storage {
@@ -1764,4 +1905,38 @@ sub config_aware_base_mkdir {
}
}
+sub get_snap_path {
+ my ($path, $snap) = @_;
+
+ my $basepath = "";
+ my $baseformat = "";
+ if ($path =~ m/^((.*)(vm-(\d+)-disk-(\d+)))(-snap-(.*))?\.(raw|qcow2)/) {
+ $basepath = $1;
+ $baseformat = $8;
+ }
+ my $format = $snap ? 'qcow2' : $baseformat;
+ my $snappath = $snap ? $basepath."-snap-$snap.$format" : undef;
+
+ return $snappath;
+}
+
+sub get_snapname_from_path {
+ my ($path) = @_;
+
+ if ($path =~ m/^((.*)(vm-(\d+)-disk-(\d+)))(-snap-(.*))?\.(raw|qcow2)/) {
+ my $snapname = $7;
+ return $snapname;
+ }
+ die "can't parse snapname from path";
+}
+
+sub get_current_snapshot {
+ my ($class, $scfg, $storeid, $volname) = @_;
+ #IMPROVE ME: faster way to find current snapshot? (search the most recent created snapshot file ? need to works with lvm volume too)
+
+ return if !$scfg->{snapext};
+ my $snapshots = $class->volume_snapshot_info($scfg, $storeid, $volname);
+ return $snapshots->{current};
+}
+
1;
--
2.39.2
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