From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [PATCH RFC 1/7] virtio_ring: add new functions
	virtqueue{_set_broken()/_is_broken()}
Date: Wed, 23 Oct 2013 10:36:25 +1030
Message-ID: <87zjq0j1fi.fsf@rustcorp.com.au>
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To: Heinz Graalfs <graalfs@linux.vnet.ibm.com>, mst@redhat.com, virtualization@lists.linux-foundation.org
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Heinz Graalfs <graalfs@linux.vnet.ibm.com> writes:
> This patch adds 2 new functions:
>
> virtqueue_set_broken(): to be called when a virtqueue kick operation fails.
>
> virtqueue_is_broken(): can be called to query the virtqueue state after a host
> was kicked.
>
> Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>

Thanks for doing this!

But as shown by the following patches, the separation of kick and broken
test is a bad API.  We should make virtqueue_kick() and
virtqueue_notify() return a bool (ie. vq->broken).

We'll still need virtqueue_is_broken(), as it would be nice to make all
callers to virtqueue_get_buf() check it as well.

Cheers,
Rusty.