Fabian Grünbichler <f.gruenbich...@proxmox.com> writes:
> From: John Snow <js...@redhat.com>
>
> This patch adds support for the "BITMAP" sync mode to drive-mirror and
> blockdev-mirror. It adds support only for the BitmapSyncMode "never,"
> because it's the simplest mode.
>
> This mode simply uses a user-provided bitmap as an initial copy
> manifest, and then does not clear any bits in the bitmap at the
> conclusion of the operation.
>
> Any new writes dirtied during the operation are copied out, in contrast
> to backup. Note that whether these writes are reflected in the bitmap
> at the conclusion of the operation depends on whether that bitmap is
> actually recording!
>
> This patch was originally based on one by Ma Haocong, but it has since
> been modified pretty heavily.
>
> Suggested-by: Ma Haocong <mahaoc...@didichuxing.com>
> Signed-off-by: Ma Haocong <mahaoc...@didichuxing.com>
> Signed-off-by: John Snow <js...@redhat.com>
> Signed-off-by: Fabian Grünbichler <f.gruenbich...@proxmox.com>
> ---
[...]
> diff --git a/qapi/block-core.json b/qapi/block-core.json
> index 2d94873ca0..dac5497084 100644
> --- a/qapi/block-core.json
> +++ b/qapi/block-core.json
> @@ -1961,10 +1961,19 @@
> # (all the disk, only the sectors allocated in the topmost image, or
> # only new I/O).
> #
> +# @bitmap: The name of a bitmap to use for sync=bitmap mode. This argument
> must
> +# be present for bitmap mode and absent otherwise. The bitmap's
What is "bitmap mode"? Do you mean "present when @bitmap-mode is, else
absent"?
> +# granularity is used instead of @granularity (since 5.2).
> +#
> +# @bitmap-mode: Specifies the type of data the bitmap should contain after
> +# the operation concludes. Must be present if sync is "bitmap".
> +# Must NOT be present otherwise. (Since 5.2)
> +#
> # @granularity: granularity of the dirty bitmap, default is 64K
> # if the image format doesn't have clusters, 4K if the clusters
> # are smaller than that, else the cluster size. Must be a
> -# power of 2 between 512 and 64M (since 1.4).
> +# power of 2 between 512 and 64M. Must not be specified if
> +# @bitmap is present (since 1.4).
> #
Is @granularity forbidden with @bitmap because it makes no sense?
If yes, then it doesn't actually default to anything then, does it?
Looks like we have
sync 'bitmap' anything else
-------------------------------------------------
bitmap required forbidden
bitmap-mode required forbidden
granularity forbidden optional
Correct?
> # @buf-size: maximum amount of data in flight from source to
> # target (since 1.4).
> @@ -2002,7 +2011,9 @@
> { 'struct': 'DriveMirror',
> 'data': { '*job-id': 'str', 'device': 'str', 'target': 'str',
> '*format': 'str', '*node-name': 'str', '*replaces': 'str',
> - 'sync': 'MirrorSyncMode', '*mode': 'NewImageMode',
> + 'sync': 'MirrorSyncMode', '*bitmap': 'str',
> + '*bitmap-mode': 'BitmapSyncMode',
> + '*mode': 'NewImageMode',
> '*speed': 'int', '*granularity': 'uint32',
> '*buf-size': 'int', '*on-source-error': 'BlockdevOnError',
> '*on-target-error': 'BlockdevOnError',
[Same for blockdev-mirror...]
