Re: [Qemu-devel] [PATCH V4 1/3] block: Add bdrv_are_busy()

[Luiz Capitulino <lcapitulino@redhat.com>]

On Mon, 23 Jul 2012 16:22:58 +0200
benoit.canet@gmail.com wrote:

> From: Benoît Canet <benoit@irqsave.net>
> 
> bdrv_are_busy will be used to check if any of the bs are in use
> or if one of them have a running block job.
> 
> The first user will be qmp_migrate().
> 
> Signed-off-by: Benoit Canet <benoit@irqsave.net>
> ---
>  block.c |   13 +++++++++++++
>  block.h |    2 ++
>  2 files changed, 15 insertions(+)
> 
> diff --git a/block.c b/block.c
> index ce7eb8f..bc8f160 100644
> --- a/block.c
> +++ b/block.c
> @@ -4027,6 +4027,19 @@ out:
>      return ret;
>  }
>  
> +int bdrv_are_busy(void)
> +{
> +    BlockDriverState *bs;
> +
> +    QTAILQ_FOREACH(bs, &bdrv_states, list) {
> +        if (bs->job || bdrv_in_use(bs)) {
> +            return -EBUSY;
> +        }
> +    }

IMO, this should return true/false. The name is a bit misleading too, as it
gives the impression that are existing bdrvs are busy. I'd call it
bdrv_any_busy() or bdrv_any_in_use().

> +
> +    return 0;
> +}
> +
>  void *block_job_create(const BlockJobType *job_type, BlockDriverState *bs,
>                         int64_t speed, BlockDriverCompletionFunc *cb,
>                         void *opaque, Error **errp)
> diff --git a/block.h b/block.h
> index c89590d..0a3de2f 100644
> --- a/block.h
> +++ b/block.h
> @@ -337,6 +337,8 @@ void bdrv_disable_copy_on_read(BlockDriverState *bs);
>  void bdrv_set_in_use(BlockDriverState *bs, int in_use);
>  int bdrv_in_use(BlockDriverState *bs);
>  
> +int bdrv_are_busy(void);
> +
>  enum BlockAcctType {
>      BDRV_ACCT_READ,
>      BDRV_ACCT_WRITE,