[libvirt] [PATCH 3/6] storage:dir: adapts .uploadVol .dowloadVol for ploop volume

[Olga Krishtal]

On 18/02/16 16:57, Ján Tomko wrote:
> On Wed, Feb 17, 2016 at 02:40:02PM +0300, Olga Krishtal wrote:
>> In case of ploop volume, target path of the volume is the path to the
>> directory that contains image file named root.hds and DiskDescriptor.xml.
>> While using uploadVol and downloadVol callbacks we need to open root.hds
>> itself. To accomplish this goal we must change path from
>> path/to/ploop directory to path/to/ploop/root.hds
>>
>> In case of .uploadVol, we have to additionaly update DiskDescriptor.xml
>>
>> Signed-off-by: Olga Krishtal <okrishtal at virtuozzo.com>
>> ---
>>   src/storage/storage_backend.c | 66 +++++++++++++++++++++++++++++++++++++++++--
>>   1 file changed, 64 insertions(+), 2 deletions(-)
>>
>> diff --git a/src/storage/storage_backend.c b/src/storage/storage_backend.c
>> index 9f0e020..ac44fdf 100644
>> --- a/src/storage/storage_backend.c
>> +++ b/src/storage/storage_backend.c
>> @@ -2023,12 +2023,63 @@ virStorageBackendVolUploadLocal(virConnectPtr conn ATTRIBUTE_UNUSED,
>>                                   unsigned long long len,
>>                                   unsigned int flags)
>>   {
>> +    char *path = NULL;
>> +    char *target_path = vol->target.path;
>> +    int ret;
>> +    virCommandPtr cmd = NULL;
>> +    char *create_tool = NULL;
>> +
>>       virCheckFlags(0, -1);
>>   
>>       /* Not using O_CREAT because the file is required to already exist at
>>        * this point */
>> -    return virFDStreamOpenBlockDevice(stream, vol->target.path,
>> +    if (vol->target.format != VIR_STORAGE_FILE_PLOOP) {
>> +        return virFDStreamOpenBlockDevice(stream, target_path,
>>                                         offset, len, O_WRONLY);
>> +    } else {
> Looking at the last patch, it seems a volume could be detected as
> VIR_STORAGE_FILE_PLOOP if it's a disk image matching the magic,
> but this code assumes it's a directory with "root.hds" image and the
> XML.
>
>> +        if (virAsprintf(&path, "%s/root.hds", vol->target.path) < 0)
>> +            return -1;
> I thought the target.path was already pointing to the image, not
> directory.
>
> Jan
The thing is that that volume target.path is path to folder with 
root.hds and DiskDescriptor.xml.
And after resize we have to update DiskDescriptor.xml. This can be done 
only after volume will be fully
upload, I mean after stream operations will be finished. Now I am 
looking for the correct place to do it.
I think about refreshPool.  But not quite sure yet.