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. This series adds support for block exports on an inactive node (needed for shared storage migration with qemu-storage-daemon) only to NBD. Adding it to other export types will be done in a future series. Kevin Wolf (9): block: Allow inactivating already inactive nodes block: Add option to create inactive nodes block: Support inactive nodes in blk_insert_bs() block/export: Don't ignore image activation error in blk_exp_add() block/export: Add option to allow export of inactive nodes nbd/server: Support inactive nodes block: Add blockdev-set-active QMP command iotests: Add filter_qtest() iotests: Add qsd-migrate case qapi/block-core.json | 38 +++++ qapi/block-export.json | 10 +- include/block/block-common.h | 1 + include/block/block-global-state.h | 6 + include/block/export.h | 3 + block.c | 50 ++++++- block/block-backend.c | 14 +- block/export/export.c | 29 +++- blockdev.c | 32 +++++ nbd/server.c | 17 +++ tests/qemu-iotests/iotests.py | 4 + tests/qemu-iotests/041 | 4 +- tests/qemu-iotests/165 | 4 +- tests/qemu-iotests/tests/copy-before-write | 3 +- tests/qemu-iotests/tests/migrate-bitmaps-test | 7 +- tests/qemu-iotests/tests/qsd-migrate | 132 ++++++++++++++++++ tests/qemu-iotests/tests/qsd-migrate.out | 51 +++++++ 17 files changed, 379 insertions(+), 26 deletions(-) create mode 100755 tests/qemu-iotests/tests/qsd-migrate create mode 100644 tests/qemu-iotests/tests/qsd-migrate.out -- 2.48.1
