Re: [Qemu-devel] [PATCH 4/7] block/vpc: Improve vpc_open (optimisation and error handling)

[Kevin Wolf]

Am 01.02.2013 22:51, schrieb Stefan Weil:
> * Always read the footer at the end of the image.
>   The footer exists for all kinds of VHD images, so there is no need
>   to read its copy at the start of dynamic VHD images.
> 
> * Return error codes from bdrv_pread like in other block drivers.
> 
> * Return -EMEDIUMTYPE for wrong medium (missing signature).
> 
> * It's not necessary to return 0 on success, >= 0 is sufficient.
> 
> Signed-off-by: Stefan Weil <address@hidden>
> ---
>  block/vpc.c |   46 ++++++++++++++++++++++------------------------
>  1 file changed, 22 insertions(+), 24 deletions(-)

> @@ -271,9 +270,8 @@ static int vpc_open(BlockDriverState *bs, int flags)
>                "vpc", bs->device_name, "live migration");
>      migrate_add_blocker(s->migration_blocker);
>  
> -    return 0;
>   fail:
> -    return err;
> +    return ret;
>  }

I'd rather leave the return 0; there, it's more obvious than reusing a
return value from "somewhere", of which we just happen know that it
contains a non-negative number if we did the previous error handling right.

Kevin