On Fri, Feb 16, 2018 at 01:16:20PM +0000, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <[email protected]>
>
> This message is sent just before the end of postcopy to get the
> client to stop using userfault since we wont respond to any more
> requests. It should close userfaultfd so that any other pages
> get mapped to the backing file automatically by the kernel, since
> at this point we know we've received everything.
>
> Signed-off-by: Dr. David Alan Gilbert <[email protected]>
> Reviewed-by: Peter Xu <[email protected]>
> ---
> contrib/libvhost-user/libvhost-user.c | 23 +++++++++++++++++++++++
> contrib/libvhost-user/libvhost-user.h | 1 +
> docs/interop/vhost-user.txt | 8 ++++++++
> hw/virtio/vhost-user.c | 1 +
> 4 files changed, 33 insertions(+)
>
> diff --git a/contrib/libvhost-user/libvhost-user.c
> b/contrib/libvhost-user/libvhost-user.c
> index 1b224af706..1f988ab787 100644
> --- a/contrib/libvhost-user/libvhost-user.c
> +++ b/contrib/libvhost-user/libvhost-user.c
> @@ -99,6 +99,7 @@ vu_request_to_string(unsigned int req)
> REQ(VHOST_USER_SET_CONFIG),
> REQ(VHOST_USER_POSTCOPY_ADVISE),
> REQ(VHOST_USER_POSTCOPY_LISTEN),
> + REQ(VHOST_USER_POSTCOPY_END),
> REQ(VHOST_USER_MAX),
> };
> #undef REQ
> @@ -1095,6 +1096,26 @@ vu_set_postcopy_listen(VuDev *dev, VhostUserMsg *vmsg)
> vmsg->payload.u64 = 0; /* Success */
> return true;
> }
> +
> +static bool
> +vu_set_postcopy_end(VuDev *dev, VhostUserMsg *vmsg)
> +{
> + DPRINT("%s: Entry\n", __func__);
> + dev->postcopy_listening = false;
> + if (dev->postcopy_ufd > 0) {
> + close(dev->postcopy_ufd);
> + dev->postcopy_ufd = -1;
> + DPRINT("%s: Done close\n", __func__);
> + }
> +
> + vmsg->fd_num = 0;
> + vmsg->payload.u64 = 0;
> + vmsg->size = sizeof(vmsg->payload.u64);
> + vmsg->flags = VHOST_USER_VERSION | VHOST_USER_REPLY_MASK;
> + DPRINT("%s: exit\n", __func__);
> + return true;
> +}
> +
> static bool
> vu_process_message(VuDev *dev, VhostUserMsg *vmsg)
> {
> @@ -1170,6 +1191,8 @@ vu_process_message(VuDev *dev, VhostUserMsg *vmsg)
> return vu_set_postcopy_advise(dev, vmsg);
> case VHOST_USER_POSTCOPY_LISTEN:
> return vu_set_postcopy_listen(dev, vmsg);
> + case VHOST_USER_POSTCOPY_END:
> + return vu_set_postcopy_end(dev, vmsg);
> default:
> vmsg_close_fds(vmsg);
> vu_panic(dev, "Unhandled request: %d", vmsg->request);
> diff --git a/contrib/libvhost-user/libvhost-user.h
> b/contrib/libvhost-user/libvhost-user.h
> index fcba53c3c3..9696b89f6e 100644
> --- a/contrib/libvhost-user/libvhost-user.h
> +++ b/contrib/libvhost-user/libvhost-user.h
> @@ -84,6 +84,7 @@ typedef enum VhostUserRequest {
> VHOST_USER_SET_CONFIG = 25,
> VHOST_USER_POSTCOPY_ADVISE = 26,
> VHOST_USER_POSTCOPY_LISTEN = 27,
> + VHOST_USER_POSTCOPY_END = 28,
> VHOST_USER_MAX
> } VhostUserRequest;
>
> diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt
> index 5bbcab2cc4..4bf7d8ef99 100644
> --- a/docs/interop/vhost-user.txt
> +++ b/docs/interop/vhost-user.txt
> @@ -697,6 +697,14 @@ Master message types
>
> Master advises slave that a transition to postcopy mode has happened.
>
> + * VHOST_USER_POSTCOPY_END
> + Id: 28
> + Slave payload: u64
> +
> + Master advises that postcopy migration has now completed. The
> + slave must disable the userfaultfd. The response is an acknowledgement
> + only.
> +
> Slave message types
> -------------------
>
Which protocol feature enables this message?
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index 74807091a0..cf7923b25f 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -78,6 +78,7 @@ typedef enum VhostUserRequest {
> VHOST_USER_SET_CONFIG = 25,
> VHOST_USER_POSTCOPY_ADVISE = 26,
> VHOST_USER_POSTCOPY_LISTEN = 27,
> + VHOST_USER_POSTCOPY_END = 28,
> VHOST_USER_MAX
> } VhostUserRequest;
>
> --
> 2.14.3
