From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <ian.campbell@citrix.com>
Subject: Re: [PATCH v3 20/24] xen/passthrough: Extend
 XEN_DOMCTL_assign_device to support DT device
Date: Fri, 20 Feb 2015 17:17:23 +0000
Message-ID: <1424452643.30924.368.camel@citrix.com>
References: <1421159133-31526-1-git-send-email-julien.grall@linaro.org>
	<1421159133-31526-21-git-send-email-julien.grall@linaro.org>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xen.org>
Received: from mail6.bemta4.messagelabs.com ([85.158.143.247])
	by lists.xen.org with esmtp (Exim 4.72)
	(envelope-from <Ian.Campbell@citrix.com>) id 1YOrp8-000186-Kg
	for xen-devel@lists.xenproject.org; Fri, 20 Feb 2015 17:57:10 +0000
In-Reply-To: <1421159133-31526-21-git-send-email-julien.grall@linaro.org>
List-Unsubscribe: <http://lists.xen.org/cgi-bin/mailman/options/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xen.org>
List-Help: <mailto:xen-devel-request@lists.xen.org?subject=help>
List-Subscribe: <http://lists.xen.org/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=subscribe>
Sender: xen-devel-bounces@lists.xen.org
Errors-To: xen-devel-bounces@lists.xen.org
To: Julien Grall <julien.grall@linaro.org>, Daniel De Graaf <dgdegra@tycho.nsa.gov>
Cc: Wei Liu <wei.liu2@citrix.com>, Ian Jackson <ian.jackson@eu.citrix.com>, tim@xen.org, stefano.stabellini@citrix.com, Jan Beulich <jbeulich@suse.com>, xen-devel@lists.xenproject.org
List-Id: xen-devel@lists.xenproject.org

On Tue, 2015-01-13 at 14:25 +0000, Julien Grall wrote:
> TODO: Update the commit message
> 
> A device node is described by a path. It will be used to retrieved the
> node in the device tree and assign the related device to the domain.
> 
> Only device protected by an IOMMU can be assigned to a guest.
> 
> Signed-off-by: Julien Grall <julien.grall@linaro.org>
> Cc: Ian Jackson <ian.jackson@eu.citrix.com>
> Cc: Wei Liu <wei.liu2@citrix.com>
> Cc: Jan Beulich <jbeulich@suse.com>
> 
> ---
>     Changes in v2:
>         - Use a different number for XEN_DOMCTL_assign_dt_device
> ---
>  tools/libxc/include/xenctrl.h         | 10 ++++
>  tools/libxc/xc_domain.c               | 95 ++++++++++++++++++++++++++++++++--

These bits all look fine.

> +int iommu_do_dt_domctl(struct xen_domctl *domctl, struct domain *d,
> +                       XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl)
> +{
> +    int ret;
> +    struct dt_device_node *dev;
> +
> +    /* TODO: How to deal with XSM? */

Adding Daniel.

It seems the PCI ones are protected by 
        xsm_test_assign_device(XSM_HOOK, domctl->u.assign_device.machine_sbdf);

So it seem that either this needs to become "test_assign_pci_device" and
a similar "test_assign_dt_device" needs to be added and plumbed through
or it needs to grow a type parameter and take the union for the
identifier.

The code to apply an XSM context to a DT node would need consideration
too I suppose?

> +    /* TODO: Do we need to check is_dying? Mostly to protect against
> +     * hypercall trying to passthrough a device while we are
> +     * dying.

FWIW the PCI case appears not to care...

> +     */
> +
> +    switch ( domctl->cmd )
> +    {
> +    case XEN_DOMCTL_assign_device:
> +        ret = -ENOSYS;
> +        if ( domctl->u.assign_device.dev != XEN_DOMCTL_DEV_DT )
> +            break;

You added something similar to iommu_do_pci_domctl, would it not be
preferable for the caller to switch on domctl->u.assign_device.dev and
call the correct iommu_do_*_domctl?

Ian.