[PATCH qemu-server 5/5] drive: rescan drives after migrating to different storage

[Thomas Ellmenreich <t.ellmenreich@proxmox.com>]

In some cases, migrating to a different storage can change the size of
disks due to the underlying granularity of the storage. In the case of a
storage with 64MiB granularity, this can increase a 4MiB TPM disk to
64MiB. To avoid out of sync ui, rescan all disks of the migrated vm after
such a storage change.

The rescan not only adjusts the disk size, but also shows all unused
disks that may not have been shown before.

Signed-off-by: Thomas Ellmenreich <t.ellmenreich@proxmox.com>
---
 src/PVE/QemuMigrate.pm | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/PVE/QemuMigrate.pm b/src/PVE/QemuMigrate.pm
index 3845fb41..fe5f422a 100644
--- a/src/PVE/QemuMigrate.pm
+++ b/src/PVE/QemuMigrate.pm
@@ -1905,6 +1905,18 @@ sub phase3_cleanup {
         $self->cmd_logerr($cmd, errmsg => "failed to clear migrate lock");
     }
 
+    if (!$self->{opts}->{remote} && scalar(keys %{ $self->{volume_map} })) {
+        my $cmd = [@{ $self->{rem_ssh} }, 'qm', 'disk', 'rescan', '--vmid', $vmid];
+        eval {
+            PVE::Tools::run_command(
+                $cmd,
+                outfunc => sub { },
+                errfunc => sub { $self->log('warn', shift) },
+            );
+        };
+        $self->log('warn', "failed to rescan disks after migration - $@") if $@;
+    }
+
     if ($self->{opts}->{remote} && $self->{opts}->{delete}) {
         eval { PVE::QemuServer::destroy_vm($self->{storecfg}, $vmid, 1, undef, 0) };
         warn "Failed to remove source VM - $@\n" if $@;
-- 
2.47.3