Re: [Xen-devel] [PATCH v13 4/4] introduce a 'passthrough' configuration option to xl.cfg...

[Anthony PERARD <anthony.perard@xxxxxxxxxx>]

On Wed, Sep 18, 2019 at 11:41:13AM +0100, Paul Durrant wrote:
> ...and hence the ability to disable IOMMU mappings, and control EPT
> sharing.
> 
> This patch introduces a new 'libxl_passthrough' enumeration into
> libxl_domain_create_info. The value will be set by xl either when it parses
> a new 'passthrough' option in xl.cfg, or implicitly if there is passthrough
> hardware specified for the domain.
> 
> If the value of the passthrough configuration option is 'disabled' then
> the XEN_DOMCTL_CDF_iommu flag will be clear in the xen_domctl_createdomain
> flags, thus allowing the toolstack to control whether the domain gets
> IOMMU mappings or not (where previously they were globally set).
> 
> If the value of the passthrough configuration option is 'sync_pt' then
> a new 'iommu_opts' field in xen_domctl_createdomain will be set with the
> value XEN_DOMCTL_IOMMU_no_sharept. This will override the global default
> set in iommu_hap_pt_share, thus allowing the toolstack to control whether
> EPT sharing is used for the domain.
> 
> If the value of passthrough is 'enabled' then xl will choose an appropriate
> default according to the type of domain and hardware support.
> 
> NOTE: The 'iommu_memkb' overhead in libxl_domain_build_info will now only
>       be set if passthrough is 'sync_pt' (or xl has chosen this mode as
>       a default).
> 
> Signed-off-by: Paul Durrant <paul.durrant@xxxxxxxxxx>
> Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
> Acked-by: Christian Lindig <christian.lindig@xxxxxxxxxx>
> Acked-by: Julien Grall <julien.grall@xxxxxxx>

Reviewed-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>

Thanks,

-- 
Anthony PERARD

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel