Re: [PATCH RESEND v9 11/14] tools/libxl: handle the iomem parameter with the memory_mapping hcall

[Julien Grall <julien.grall@linaro.org>]

Hi Arianna,

On 07/14/2014 01:50 AM, Arianna Avanzini wrote:
> Currently, the configuration-parsing code concerning the handling of the
> iomem parameter only invokes the XEN_DOMCTL_iomem_permission hypercall.
> This commit lets the XEN_DOMCTL_memory_mapping hypercall be invoked
> after XEN_DOMCTL_iomem_permission when the iomem parameter is parsed
> from a domU configuration file, so that the address range can be mapped
> to the address space of the domU. The hypercall is invoked only in case
> of domains using an auto-translated physmap.
> 
> Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com>
> Acked-by: Ian Campbell <Ian.Campbell@eu.citrix.com>
Acked-by: Julien Grall <julien.grall@linaro.org>

Regards,

> Cc: Dario Faggioli <dario.faggioli@citrix.com>
> Cc: Paolo Valente <paolo.valente@unimore.it>
> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> Cc: Julien Grall <julien.grall@citrix.com>
> Cc: Jan Beulich <JBeulich@suse.com>
> Cc: Keir Fraser <keir@xen.org>
> Cc: Tim Deegan <tim@xen.org>
> Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>
> Cc: Andrew Cooper <andrew.cooper3@citrix.com>
> Cc: Eric Trudeau <etrudeau@broadcom.com>
> Cc: Viktor Kleinik <viktor.kleinik@globallogic.com>
> 
> ---
> 
>     v9:
>         - Enforce checks on return value of xc_domain_getinfo() as it could
>           return information concerning the wrong domain.
>         - Don't use PERROR for xc_core_* functions.
>         - Avoid emitting an error message if xc_core_auto_translated_physmap()
>           fails.
> 
>     v8:
>         - Fix wrong error message emitted when the memory_mapping DOMCTL is
>           called by a domain that is not auto-translated.
> 
>     v7:
>         - Move the check for an auto-translated physmap to xc to avoid having
>           to expose the information to libxl.
> 
>     v4:
>         - Let the hypercall be called only in case the guest uses an
>           auto-translated physmap.
> 
>     v3:
>         - Add ifdefs to let the hypercall be called only by ARM or x86
>           HVM guests, with a whitelist approach.
>         - Remove the NOTE comment.
> 
>     v2:
>         - Add a comment explaining outstanding issues.
> 
> ---
>  tools/libxc/xc_domain.c    | 10 ++++++++++
>  tools/libxl/libxl_create.c | 11 +++++++++++
>  2 files changed, 21 insertions(+)
> 
> diff --git a/tools/libxc/xc_domain.c b/tools/libxc/xc_domain.c
> index 0230c6c..27fe3b6 100644
> --- a/tools/libxc/xc_domain.c
> +++ b/tools/libxc/xc_domain.c
> @@ -1959,6 +1959,16 @@ int xc_domain_memory_mapping(
>      uint32_t add_mapping)
>  {
>      DECLARE_DOMCTL;
> +    xc_dominfo_t info;
> +
> +    if ( xc_domain_getinfo(xch, domid, 1, &info) != 1 ||
> +         info.domid != domid )
> +    {
> +        PERROR("Could not get info for domain");
> +        return -EINVAL;
> +    }
> +    if ( !xc_core_arch_auto_translated_physmap(&info) )
> +        return 0;
>  
>      domctl.cmd = XEN_DOMCTL_memory_mapping;
>      domctl.domain = domid;
> diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
> index 3bfe65b..1217310 100644
> --- a/tools/libxl/libxl_create.c
> +++ b/tools/libxl/libxl_create.c
> @@ -1158,6 +1158,17 @@ static void domcreate_launch_dm(libxl__egc *egc, libxl__multidev *multidev,
>                   "failed give dom%d access to iomem range %"PRIx64"-%"PRIx64,
>                   domid, io->start, io->start + io->number - 1);
>              ret = ERROR_FAIL;
> +            continue;
> +        }
> +        ret = xc_domain_memory_mapping(CTX->xch, domid,
> +                                       io->gfn, io->start,
> +                                       io->number, 1);
> +        if (ret < 0) {
> +            LOGE(ERROR,
> +                 "failed to map to dom%d iomem range %"PRIx64"-%"PRIx64
> +                 " to guest address %"PRIx64,
> +                 domid, io->start, io->start + io->number - 1, io->gfn);
> +            ret = ERROR_FAIL;
>          }
>      }
>  
> 


-- 
Julien Grall