Am 22.08.2024 um 12:52 hat luzhipeng geschrieben:
> issue:https://gitlab.com/qemu-project/qemu/-/issues/1357
> empty vmdk only contains metadata, ovftool failed.
> So it allocates more one sector for empty disk. the ovftool
> command line: ovftool input.ovf output.ova
>
> Signed-off-by: luzhipeng <[email protected]>
I think this commit message needs more of the information from the bug
report, otherwise it seems unexplainable why adding an empty sector
should make a difference.
> diff --git a/block/vmdk.c b/block/vmdk.c
> index 78f6433607..283dee9b49 100644
> --- a/block/vmdk.c
> +++ b/block/vmdk.c
> @@ -2286,7 +2286,7 @@ vmdk_init_extent(BlockBackend *blk, int64_t filesize,
> bool flat, bool compress,
> goto exit;
> }
>
> - ret = blk_co_truncate(blk, le64_to_cpu(header.grain_offset) << 9, false,
> + ret = blk_co_truncate(blk, (le64_to_cpu(header.grain_offset) << 9) +
> BDRV_SECTOR_SIZE,
> + false, PREALLOC_MODE_OFF, 0, errp);
> if (ret < 0) {
> goto exit;
This is not a good fix. It means that we will always leave an empty
sector after the header, even if more data follows.
Does the problem really only happen with empty images? I think we don't
necessarily add an end-of-stream marker for other images either, we just
align the image size to full sectors at the end of 'qemu-img convert'.
I wonder if vmdk_co_pwritev_compressed() should be changed to write both
a footer and an explicit end-of-stream marker for streamOptimized images
in the bytes == 0 case.
Kevin
