Re: [Qemu-devel] [PATCH 4/6] qcow2: Update total_sectors when resizing the image

[Kevin Wolf <kwolf@redhat.com>]

Am 29.07.2018 um 23:27 hat Leonid Bloch geschrieben:
> Signed-off-by: Leonid Bloch <lbloch@janustech.com>
> ---
>  block/qcow2.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/block/qcow2.c b/block/qcow2.c
> index ec9e6238a0..223d351e40 100644
> --- a/block/qcow2.c
> +++ b/block/qcow2.c
> @@ -3646,6 +3646,8 @@ static int coroutine_fn qcow2_co_truncate(BlockDriverState *bs, int64_t offset,
>          }
>      }
>  
> +    bs->total_sectors = offset / 512;
> +
>      /* write updated header.size */
>      offset = cpu_to_be64(offset);
>      ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size),

This shouldn't be necessary, bdrv_co_truncate() already updates
bs->total_sectors after calling the block driver.

If this is needed by one of the following patches, we need a comment
that explains why this seemingly superfluous assignment is actually
necessary.

Also, 512 should be BDRV_SECTOR_SIZE.

Kevin