QMP command for block device reactivation after migration
Merge Request Required Information
Summary of Changes
This series adds a mechanism that allows the user or management tool to manually activate and inactivate block nodes instead of fully relying on the automatic management in the migration code.
One case where this is needed is for migration with shared storage and devices backed by qemu-storage-daemon, which as an external process is not involved in the VM migration. Management tools can manually orchestrate the handover in this scenario. The new qemu-iotests case qsd-migrate demonstrates this.
There are other cases without qemu-storage-daemon where manual management is necessary. For example, after migration, the destination VM only activates images on 'cont', but after migrating a paused VM, the user may want to perform operations on a block node while the VM is still paused.