[PATCH qemu-server 1/4] qemu_img convert : add external snapshot support

[Alexandre Derumier]

for external snapshot, we simply use snap volname as src.
don't use internal snapshot option in the command line.

Signed-off-by: Alexandre Derumier <alexandre.derumier at groupe-cyllene.com>
---
 src/PVE/QemuServer/QemuImage.pm        |  6 ++-
 src/test/run_qemu_img_convert_tests.pl | 59 ++++++++++++++++++++++++++
 2 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/src/PVE/QemuServer/QemuImage.pm b/src/PVE/QemuServer/QemuImage.pm
index 38f7d52b..2502a32d 100644
--- a/src/PVE/QemuServer/QemuImage.pm
+++ b/src/PVE/QemuServer/QemuImage.pm
@@ -71,11 +71,15 @@ sub convert {
     my $dst_format = checked_volume_format($storecfg, $dst_volid);
     my $dst_path = PVE::Storage::path($storecfg, $dst_volid);
     my $dst_is_iscsi = ($dst_path =~ m|^iscsi://|);
+    my $support_qemu_snapshots = PVE::Storage::volume_support_qemu_snapshot($storecfg, $src_volid);
 
     my $cmd = [];
     push @$cmd, '/usr/bin/qemu-img', 'convert', '-p', '-n';
     push @$cmd, '-l', "snapshot.name=$snapname"
-        if $snapname && $src_format && $src_format eq "qcow2";
+        if $snapname
+        && $src_format eq 'qcow2'
+        && $support_qemu_snapshots
+        && $support_qemu_snapshots eq 'internal';
     push @$cmd, '-t', 'none' if $dst_scfg->{type} eq 'zfspool';
     push @$cmd, '-T', $cachemode if defined($cachemode);
     push @$cmd, '-r', "${bwlimit}K" if defined($bwlimit);
diff --git a/src/test/run_qemu_img_convert_tests.pl b/src/test/run_qemu_img_convert_tests.pl
index b5a457c3..d6118b33 100755
--- a/src/test/run_qemu_img_convert_tests.pl
+++ b/src/test/run_qemu_img_convert_tests.pl
@@ -21,6 +21,15 @@ my $storage_config = {
             type => "dir",
             shared => 0,
         },
+        localsnapext => {
+            content => {
+                images => 1,
+            },
+            path => "/var/lib/vzsnapext",
+            type => "dir",
+            'external-snapshots' => 1,
+            shared => 0,
+        },
         btrfs => {
             content => {
                 images => 1,
@@ -61,6 +70,13 @@ my $storage_config = {
                 images => 1,
             },
         },
+        "lvm-store" => {
+            vgname => "pve",
+            type => "lvm",
+            content => {
+                images => 1,
+            },
+        },
         "zfs-over-iscsi" => {
             type => "zfs",
             iscsiprovider => "LIO",
@@ -469,6 +485,49 @@ my $tests = [
             "/var/lib/vz/images/$vmid/vm-$vmid-disk-0.raw",
         ],
     },
+    {
+        name => "qcow2_external_snapshot",
+        parameters => [
+            "localsnapext:$vmid/vm-$vmid-disk-0.qcow2",
+            "local:$vmid/vm-$vmid-disk-0.raw",
+            1024 * 10,
+            { snapname => 'foo' },
+        ],
+        expected => [
+            "/usr/bin/qemu-img",
+            "convert",
+            "-p",
+            "-n",
+            "-f",
+            "qcow2",
+            "-O",
+            "raw",
+            "/var/lib/vzsnapext/images/$vmid/snap-foo-vm-$vmid-disk-0.qcow2",
+            "/var/lib/vz/images/$vmid/vm-$vmid-disk-0.raw",
+        ],
+    },
+    {
+        name => "lvmqcow2_external_snapshot",
+        parameters => [
+            "lvm-store:vm-$vmid-disk-0.qcow2",
+            "local:$vmid/vm-$vmid-disk-0.raw",
+            1024 * 10,
+            { snapname => 'foo' },
+        ],
+        expected => [
+            "/usr/bin/qemu-img",
+            "convert",
+            "-p",
+            "-n",
+            "-f",
+            "qcow2",
+            "-O",
+            "raw",
+            "/dev/pve/snap_vm-8006-disk-0_foo.qcow2",
+            "/var/lib/vz/images/$vmid/vm-$vmid-disk-0.raw",
+        ],
+    },
+
 ];
 
 my $command;
-- 
2.39.5