On Fri, Oct 21, 2016 at 02:24:39PM +0800, Liang Li wrote:
> Define a new feature bit which supports a new virtual queue. This
> new virtual qeuque is for information exchange between hypervisor
> and guest. The VMM hypervisor can make use of this virtual queue
> to request the guest do some operations, e.g. drop page cache,
> synchronize file system, etc.
Can we call this something more informative pls?
host request vq?
> And the VMM hypervisor can get some
> of guest's runtime information through this virtual queue, e.g. the
> guest's unused page information, which can be used for live migration
> optimization.
I guess the idea is that guest gets requests from host and
then responds to them on this vq. Pls document.
>
> Signed-off-by: Liang Li <liang.z.li@xxxxxxxxx>
> Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: Cornelia Huck <cornelia.huck@xxxxxxxxxx>
> Cc: Amit Shah <amit.shah@xxxxxxxxxx>
> ---
> 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 d3b182a..3a9d633 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_PAGE_BITMAP 3 /* Send page info with bitmap */
> +#define VIRTIO_BALLOON_F_MISC_VQ 4 /* Misc info virtqueue */
>
> /* Size of a PFN in the balloon interface. */
> #define VIRTIO_BALLOON_PFN_SHIFT 12
> @@ -101,4 +102,25 @@ struct balloon_bmap_hdr {
> __virtio64 bmap_len;
> };
>
> +enum balloon_req_id {
> + /* Get unused pages information */
unused page information
> + BALLOON_GET_UNUSED_PAGES,
> +};
> +
> +enum balloon_flag {
> + /* Have more data for a request */
> + BALLOON_FLAG_CONT,
> + /* No more data for a request */
> + BALLOON_FLAG_DONE,
> +};
is this a bit number or a value? Pls name consistently.
> +
> +struct balloon_req_hdr {
> + /* Used to distinguish different request */
requests
> + __virtio16 cmd;
> + /* Reserved */
> + __virtio16 reserved[3];
> + /* Request parameter */
> + __virtio64 param;
> +};
> +
> #endif /* _LINUX_VIRTIO_BALLOON_H */
Prefix structs with virtio_ as well pls.
Also, wouldn't it simplify code if we use __le for new structs?
> --
> 1.8.3.1
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>