Re: [Qemu-devel] [PATCH v12 10/19] block: Add QMP support for streaming to an intermediate layer

[Alberto Garcia]

On Wed 26 Oct 2016 04:58:00 PM CEST, Kevin Wolf <address@hidden> wrote:
> Am 26.10.2016 um 12:29 hat Alberto Garcia geschrieben:
>> This patch makes the 'device' parameter of the 'block-stream' command
>> accept a node name that is not a root node.
>> 
>> In addition to that, operation blockers will be checked in all
>> intermediate nodes between the top and the base node.
>> 
>> Signed-off-by: Alberto Garcia <address@hidden>
>
>> --- a/qapi/block-core.json
>> +++ b/qapi/block-core.json
>> @@ -1464,6 +1464,10 @@
>>  # with query-block-jobs.  The operation can be stopped before it has 
>> completed
>>  # using the block-job-cancel command.
>>  #
>> +# The node that receives the data is called the top image, can be located in
>> +# any part of the chain (but always above the base image; see below) and 
>> can be
>> +# specified using its device or node name.
>> +#
>>  # If a base file is specified then sectors are not copied from that base 
>> file and
>>  # its backing chain.  When streaming completes the image file will have the 
>> base
>>  # file as its backing file.  This can be used to stream a subset of the 
>> backing
>> @@ -1475,12 +1479,12 @@
>>  # @job-id: #optional identifier for the newly-created block job. If
>>  #          omitted, the device name will be used. (Since 2.7)
>>  #
>> -# @device: the device name or node-name of a root node
>> +# @device: the device or node name of the top image
>>  #
>>  # @base:   #optional the common backing file name
>>  #
>> -# @backing-file: #optional The backing file string to write into the active
>> -#                          layer. This filename is not validated.
>> +# @backing-file: #optional The backing file string to write into the top
>> +#                          image. This filename is not validated.
>>  #
>>  #                          If a pathname string is such that it cannot be
>>  #                          resolved by QEMU, that means that subsequent QMP 
>> or
>
> As we discussed in v10, this is not discoverable through
> introspection.  You added patch 18 which introduces a base-node option
> and can serve as a witness for the changed semantics, which is
> good. Should this be documented here?

In the commit message I don't see why not, but in the JSON file?

"This feature was added together with the base-node parameter" ?

Berto