[Qemu-devel] Re: [PATCH 07/13] blockdev: Means to destroy blockdev only if made with drive_init()

[Kevin Wolf <kwolf@redhat.com>]

Am 02.06.2010 18:55, schrieb Markus Armbruster:
> All drives are still made that way.  They get destroyed along with
> their device.  That's inappropriate for the alternative way to make
> blockdevs that will appear later in this series.  These won't have a
> DriveInfo.
> 
> blockdev_detach() destroys the blockdev only if it has a DriveInfo.
> 
> blockdev_attach() does nothing for now.  It'll be fleshed out later.
> 
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> ---
>  blockdev.c |   35 +++++++++++++++++++++++++++++++++++
>  blockdev.h |    7 +++++++
>  2 files changed, 42 insertions(+), 0 deletions(-)
> 
> diff --git a/blockdev.c b/blockdev.c
> index ace74e4..f90d4fc 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -1,8 +1,12 @@
>  /*
>   * QEMU host block devices
>   *
> + * Copyright (C) 2010 Red Hat Inc.
>   * Copyright (c) 2003-2008 Fabrice Bellard
>   *
> + * Authors:
> + *  Markus Armbruster <armbru@redhat.com>,
> + *
>   * This work is licensed under the terms of the GNU GPL, version 2 or
>   * later.  See the COPYING file in the top-level directory.
>   */
> @@ -17,6 +21,37 @@
>  
>  static QTAILQ_HEAD(drivelist, DriveInfo) drives = QTAILQ_HEAD_INITIALIZER(drives);
>  
> +static int blockdev_del_dinfo(BlockDriverState *bs)
> +{
> +    DriveInfo *dinfo, *next_dinfo;
> +    int res = 0;
> +
> +    QTAILQ_FOREACH_SAFE(dinfo, &drives, next, next_dinfo) {
> +        if (dinfo->bdrv == bs) {
> +            qemu_opts_del(dinfo->opts);
> +            QTAILQ_REMOVE(&drives, dinfo, next);
> +            qemu_free(dinfo);
> +            res = 1;
> +        }
> +    }
> +
> +    return res;

Can it happen that a BlockDriverState belongs to multiple DriveInfos? If
no, why not returning in the loop? Wouldn't need a FOREACH_SAFE then, too.

It's not worth respinning because of this one, but there were more
comments and I think you'll send a v2 for the actual -blockdev option
anyway once we have decided how to do it.

I have applied patches 1 to 6 now, and I think I could safely go on
until patch 9 if the minor improvements that were mentioned in comments
are made. I'd ignore patch 10 to 13 for now.

Is this what you would have expected or should I handle anything in a
different way?

Kevin