[PATCH v3 0/6] qemu: implementation of transient disk option

Masayoshi Mizuma msys.mizuma at gmail.com
Thu Sep 17 13:30:39 UTC 2020

This patchset tries to implement transient option for qcow2 and raw
format disk.

It gets user available to set <transient/> to the domain xml file like as:

    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/guest.qcow2'/>
      <target dev='vda' bus='virtio'/>

Any changes which the Guest does to the disk is dropped when the Guest
is shutdowned.

There are some limitations for transient disk option so far:

- Supported disk format is qcow2 and raw
- blockdev capability is required for qemu
- Following features are blocked with transient disk option
  - blockjobs 
  - Migration
  - Disk hotplug

Masayoshi Mizuma (6):
  qemu: Block blockjobs when transient disk option is enabled
  qemu: Block disk hotplug when transient disk option is enabled
  qemu: Block migration when transient disk option is enabled
  qemu: update the validation for transient disk option
  qemu: Introduce to handle transient disk
  qemu: Add transient disk handler to start and stop the guest

 src/qemu/qemu_domain.c    |   7 +++
 src/qemu/qemu_hotplug.c   |   6 +++
 src/qemu/qemu_migration.c |  10 ++++
 src/qemu/qemu_process.c   |  10 ++++
 src/qemu/qemu_snapshot.c  | 103 +++++++++++++++++++++++++++++++++++---
 src/qemu/qemu_snapshot.h  |   5 ++
 src/qemu/qemu_validate.c  |  25 ++++++++-
 src/util/virstoragefile.c |   2 +
 src/util/virstoragefile.h |   4 ++
 9 files changed, 164 insertions(+), 8 deletions(-)


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