Re: [Qemu-devel] [PATCH 1/2] block: Do not prematurely remove "filename"

["Benoît Canet" <benoit.canet@irqsave.net>]

The Wednesday 18 Jun 2014 à 00:14:09 (+0200), Max Reitz wrote :
> If "filename" is removed from the options QDict before entering
> bdrv_open_common(), it cannot be stored in the BDS. Therefore, wait
> until it has been copied there and remove it from the options only
> afterwards.
> 
> This fixes "filename" in the BDS being empty for block drivers which do
> not need the filename because they have parsed it already (e.g. NBD).
> 
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
>  block.c | 12 +++++++++---
>  1 file changed, 9 insertions(+), 3 deletions(-)
> 
> diff --git a/block.c b/block.c
> index 43abe96..1fdfa66 100644
> --- a/block.c
> +++ b/block.c
> @@ -954,6 +954,14 @@ static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
>          bs->filename[0] = '\0';
>      }
>  
> +    if (!drv->bdrv_needs_filename) {
> +        qdict_del(options, "filename");
> +        /* The pointer "filename" may reference the just deleted QDict entry; in
> +         * any case, it is no longer needed, so indicate that by setting it to
> +         * NULL. */
> +        filename = NULL;
> +    }
> +
>      bs->drv = drv;
>      bs->opaque = g_malloc0(drv->instance_size);
>  
> @@ -1070,9 +1078,7 @@ static int bdrv_file_open(BlockDriverState *bs, const char *filename,
>              goto fail;
>          }
>  
> -        if (!drv->bdrv_needs_filename) {
> -            qdict_del(*options, "filename");
> -        } else {
> +        if (drv->bdrv_needs_filename) {
>              filename = qdict_get_str(*options, "filename");
>          }
>      }
> -- 
> 2.0.0
> 
> 
Reviewed-by: Benoit Canet <benoit@irqsave.net>