Re: [Qemu-devel] [PATCH 6/7] file-posix: Add dynamic-auto-read-only QAPI feature

[Markus Armbruster]

Eric Blake <address@hidden> writes:

> On 6/6/19 10:38 AM, Markus Armbruster wrote:
>> From: Kevin Wolf <address@hidden>
>> 
>> In commit 23dece19da4 ('file-posix: Make auto-read-only dynamic') ,
>> auto-read-only=on changed its behaviour in file-posix for the 4.0
>> release. This change cannot be detected through the usual mechanisms
>> like schema introspection. Add a new feature flag to the schema to
>> allow libvirt to detect the presence of the new behaviour.
>> 
>> Signed-off-by: Kevin Wolf <address@hidden>
>> ---
>>  qapi/block-core.json | 13 ++++++++++++-
>>  1 file changed, 12 insertions(+), 1 deletion(-)
>> 
>> diff --git a/qapi/block-core.json b/qapi/block-core.json
>> index 1defcde048..f5e1ee91f9 100644
>> --- a/qapi/block-core.json
>> +++ b/qapi/block-core.json
>> @@ -2859,6 +2859,15 @@
>>  #                         file is large, do not use in production.
>>  #                         (default: off) (since: 3.0)
>>  #
>> +# Features:
>> +# @dynamic-auto-read-only: If present, enabled auto-read-only means that the
>> +#                          driver will open the image read-only at first,
>> +#                          dynamically reopen the image file read-write when
>> +#                          the first writer is attached to the node and 
>> reopen
>> +#                          read-only when the last writer is detached. This
>> +#                          allows to give QEMU write permissions only on 
>> demand
>
> s/allows to give/allows giving/

Fixing, thanks!

>> +#                          when an operation actually needs write access.
>> +#
>>  # Since: 2.9
>>  ##
>>  { 'struct': 'BlockdevOptionsFile',
>> @@ -2868,7 +2877,9 @@
>>              '*aio': 'BlockdevAioOptions',
>>          '*drop-cache': {'type': 'bool',
>>                          'if': 'defined(CONFIG_LINUX)'},
>> -            '*x-check-cache-dropped': 'bool' } }
>> +            '*x-check-cache-dropped': 'bool' },
>> +  'features': [ { 'name': 'dynamic-auto-read-only',
>> +                  'if': 'defined(CONFIG_POSIX)' } ] }
>>  
>>  ##
>>  # @BlockdevOptionsNull:
>>