[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v3 4/8] add mode field to blockdev-snapshot-sync
From: |
Eric Blake |
Subject: |
Re: [Qemu-devel] [PATCH v3 4/8] add mode field to blockdev-snapshot-sync transaction item |
Date: |
Mon, 05 Mar 2012 11:45:33 -0700 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:10.0.1) Gecko/20120216 Thunderbird/10.0.1 |
On 03/05/2012 10:33 AM, Paolo Bonzini wrote:
> The mode field lets a management application create the snapshot
> destination outside QEMU.
>
> Right now, the only modes are "existing" and "absolute-paths". Mirroring
> introduces "no-backing-file". In the future "relative-paths" could be
> implemented too.
>
> Signed-off-by: Paolo Bonzini <address@hidden>
> ---
> blockdev.c | 25 ++++++++++++++++---------
> qapi-schema.json | 21 ++++++++++++++++++++-
> qmp-commands.hx | 10 ++++++++++
> 3 files changed, 46 insertions(+), 10 deletions(-)
>
>
> ##
> +# @NewImageMode
> +#
> +# An enumeration that tells QEMU how to set the backing file path in
> +# a new image file.
> +#
> +# @existing: QEMU should look for an existing image file.
> +#
> +# @absolute-paths: QEMU should create a new image with absolute paths
> +# for the backing file.
> +#
> +# @no-backing-file: QEMU should create a new image with no backing file.
Not present in this patch. Does it need to be rebased into the correct
part of the series?
> +#
> +# Since: 1.1
> +##
> +{ 'enum': 'NewImageMode'
> + 'data': [ 'existing', 'absolute-paths' ] }
> +
> +##
> # @BlockdevSnapshot
> #
> # @device: the name of the device to generate the snapshot from.
> @@ -1127,7 +1145,8 @@
> # @format: #optional the format of the snapshot image, default is 'qcow2'.
> ##
> { 'type': 'BlockdevSnapshot',
> - 'data': { 'device': 'str', 'snapshot-file': 'str', '*format': 'str' } }
> + 'data': { 'device': 'str', 'snapshot-file': 'str', '*format': 'str',
> + '*mode': 'NewImageMode' } }
>
> ##
> # @BlockdevAction
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index fb4f1df..7c03b62 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -705,6 +705,13 @@ A list of dictionaries is accepted, that contains the
> actions to be performed.
> For snapshots this is the device, the file to use for the new snapshot,
> and the format. The default format, if not specified, is qcow2.
>
> +Each new snapshot defaults to being created by QEMU (wiping any
> +contents if the file already exists),
so this is mode of 'absolute-paths', which is the default if mode is not
present,
> but it is also possible to reuse
> +an externally-created file. In the latter case, you should ensure that
> +the new image file has the same contents as the current one; QEMU cannot
> +perform any meaningful check. Typically this is achieved by using the
> +current image file as the backing file for the new image.
and this is mode 'existing'. Correct? If so, let's actually call that
out in the wording.
> +
> Arguments:
>
> actions array:
> @@ -715,6 +722,8 @@ actions array:
> - "device": device name to snapshot (json-string)
> - "snapshot-file": name of new image file (json-string)
> - "format": format of new image (json-string, optional)
> + - "mode": whether and how QEMU should create the snapshot file
> + (NewImageMode, optional, default "absolute-paths")
Well, this solves one of my two comments about the above wording, by
calling out the default.
--
Eric Blake address@hidden +1-919-301-3266
Libvirt virtualization library http://libvirt.org
signature.asc
Description: OpenPGP digital signature
- [Qemu-devel] [PATCH v3 5/8] qmp: convert blockdev-snapshot-sync to a wrapper around transactions, (continued)
- [Qemu-devel] [PATCH v3 1/8] fix format name for backing file, Paolo Bonzini, 2012/03/05
- [Qemu-devel] [PATCH v3 6/8] Add blkmirror block driver, Paolo Bonzini, 2012/03/05
- [Qemu-devel] [PATCH v3 7/8] add mirroring to transaction, Paolo Bonzini, 2012/03/05
- [Qemu-devel] [PATCH v3 4/8] add mode field to blockdev-snapshot-sync transaction item, Paolo Bonzini, 2012/03/05
- Re: [Qemu-devel] [PATCH v3 4/8] add mode field to blockdev-snapshot-sync transaction item,
Eric Blake <=
- [Qemu-devel] [PATCH v3 8/8] add drive-mirror command and HMP equivalent, Paolo Bonzini, 2012/03/05
- [Qemu-devel] [PATCH v3 9/8] Add the drive-reopen command, Paolo Bonzini, 2012/03/06
- [Qemu-devel] [PATCH v3 10/8] use QSIMPLEQ_FOREACH_SAFE when freeing list elements, Paolo Bonzini, 2012/03/06