From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933716AbdCHE56 (ORCPT ); Tue, 7 Mar 2017 23:57:58 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58746 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756687AbdCHE5v (ORCPT ); Tue, 7 Mar 2017 23:57:51 -0500 Date: Wed, 8 Mar 2017 06:02:26 +0200 From: "Michael S. Tsirkin" To: Wei Wang Cc: virtio-dev@lists.oasis-open.org, kvm@vger.kernel.org, qemu-devel@nongnu.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-mm@kvack.org, Liang Li , Andrew Morton , Mel Gorman , Paolo Bonzini , Cornelia Huck , Amit Shah , Dave Hansen , Andrea Arcangeli , David Hildenbrand , Liang Li Subject: Re: [PATCH v7 kernel 4/5] virtio-balloon: define flags and head for host request vq Message-ID: <20170308060158-mutt-send-email-mst@kernel.org> References: <1488519630-89058-1-git-send-email-wei.w.wang@intel.com> <1488519630-89058-5-git-send-email-wei.w.wang@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1488519630-89058-5-git-send-email-wei.w.wang@intel.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Wed, 08 Mar 2017 04:02:30 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 03, 2017 at 01:40:29PM +0800, Wei Wang wrote: > From: Liang Li > > Define the flags and head struct for a new host request virtual > queue. Guest can get requests from host and then responds to > them on this new virtual queue. > Host can make use of this virtqueue to request the guest to do > some operations, e.g. drop page cache, synchronize file system, > etc. The hypervisor can get some of guest's runtime information > through this virtual queue too, e.g. the guest's unused page > information, which can be used for live migration optimization. > > Signed-off-by: Liang Li > Signed-off-by: Wei Wang > Cc: Andrew Morton > Cc: Mel Gorman > Cc: Michael S. Tsirkin > Cc: Paolo Bonzini > Cc: Cornelia Huck > Cc: Amit Shah > Cc: Dave Hansen > Cc: Andrea Arcangeli > Cc: David Hildenbrand > Cc: Liang Li > Cc: Wei Wang I prefer this squashed into next patch makes review easier. > --- > include/uapi/linux/virtio_balloon.h | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/include/uapi/linux/virtio_balloon.h b/include/uapi/linux/virtio_balloon.h > index ed627b2..630b0ef 100644 > --- a/include/uapi/linux/virtio_balloon.h > +++ b/include/uapi/linux/virtio_balloon.h > @@ -35,6 +35,7 @@ > #define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory Stats virtqueue */ > #define VIRTIO_BALLOON_F_DEFLATE_ON_OOM 2 /* Deflate balloon on OOM */ > #define VIRTIO_BALLOON_F_CHUNK_TRANSFER 3 /* Transfer pages in chunks */ > +#define VIRTIO_BALLOON_F_HOST_REQ_VQ 4 /* Host request virtqueue */ > > /* Size of a PFN in the balloon interface. */ > #define VIRTIO_BALLOON_PFN_SHIFT 12 > @@ -94,4 +95,25 @@ struct virtio_balloon_resp_hdr { > __le32 data_len; /* Payload len in bytes */ > }; > > +enum virtio_balloon_req_id { > + /* Get unused page information */ > + BALLOON_GET_UNUSED_PAGES, > +}; > + > +enum virtio_balloon_flag { > + /* Have more data for a request */ > + BALLOON_FLAG_CONT, > + /* No more data for a request */ > + BALLOON_FLAG_DONE, > +}; > + > +struct virtio_balloon_req_hdr { > + /* Used to distinguish different requests */ > + __le16 cmd; > + /* Reserved */ > + __le16 reserved[3]; > + /* Request parameter */ > + __le64 param; > +}; > + > #endif /* _LINUX_VIRTIO_BALLOON_H */ > -- > 2.7.4