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

[Ján Tomko]

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