[OE-core] [PATCH] wic: fallback to dd, if sparse_copy does not work

[Martin Hundebøll]

On 2017-11-16 12:49, Dogukan Ergun wrote:
> Docker's aufs filesystem doesn't support file ioctl operations like FIGETBSZ
> or FIEMAP.
> Sparse_copy operation will fail if those ioctls are not supported.
> If sparse_copy fails while generating wic images, fallback to dd for copying
> filesystems on final image.
> 
> Signed-off-by: Dogukan Ergun <dogukan.ergun at gmail.com>
> ---
>   scripts/lib/wic/plugins/imager/direct.py | 10 ++++++++--
>   1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/scripts/lib/wic/plugins/imager/direct.py b/scripts/lib/wic/plugins/imager/direct.py
> index da1c061..70f93ee 100644
> --- a/scripts/lib/wic/plugins/imager/direct.py
> +++ b/scripts/lib/wic/plugins/imager/direct.py
> @@ -577,8 +577,14 @@ class PartitionedImage():
>           for part in self.partitions:
>               source = part.source_file
>               if source:
> -                # install source_file contents into a partition
> -                sparse_copy(source, self.path, seek=part.start * self.sector_size)
> +                try:
> +                    # install source_file contents into a partition
> +                    sparse_copy(source, self.path, seek=part.start * self.sector_size)
> +                except:

I guess a failing sparse_copy() would raise an IOError. Shouldn't you 
limit the except to catching only those?

// Martin

> +                    # Sparse_copy failed, fallback to dd method
> +                    dd_cmd = "dd if=%s of=%s bs=%d seek=%d count=%d conv=notrunc" % \
> +                        (source, self.path, self.sector_size, part.start, part.size_sec)
> +                    exec_cmd(dd_cmd)
>   
>                   logger.debug("Installed %s in partition %d, sectors %d-%d, "
>                                "size %d sectors", source, part.num, part.start,
>