Re: [PATCH V6.1 3/3] libxl: arm: make creation of iommu node independent of disk device

[Oleksandr <olekstysh@gmail.com>]

On 09.09.22 17:43, Viresh Kumar wrote:

Hello Viresh

> The iommu node will be required for other virtio device types too, not
> just disk device.
>
> Move the call to make_xen_iommu_node(), out of the disk device specific
> block and rename "iommu_created" variable to "iommu_needed", and set it
> to true for virtio disk device.
>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
> V6->V6.1:
> - Initialize iommu_needed at declaration time only.
> - Update comment.

Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>



>
>   tools/libs/light/libxl_arm.c | 17 ++++++++++-------
>   1 file changed, 10 insertions(+), 7 deletions(-)
>
> diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c
> index 55aee15c10b4..fe1c92383dd6 100644
> --- a/tools/libs/light/libxl_arm.c
> +++ b/tools/libs/light/libxl_arm.c
> @@ -1157,7 +1157,7 @@ static int libxl__prepare_dtb(libxl__gc *gc, libxl_domain_config *d_config,
>       size_t fdt_size = 0;
>       int pfdt_size = 0;
>       libxl_domain_build_info *const info = &d_config->b_info;
> -    bool iommu_created;
> +    bool iommu_needed = false;
>       unsigned int i;
>   
>       const libxl_version_info *vers;
> @@ -1265,22 +1265,25 @@ static int libxl__prepare_dtb(libxl__gc *gc, libxl_domain_config *d_config,
>           if (d_config->num_pcidevs)
>               FDT( make_vpci_node(gc, fdt, ainfo, dom) );
>   
> -        iommu_created = false;
>           for (i = 0; i < d_config->num_disks; i++) {
>               libxl_device_disk *disk = &d_config->disks[i];
>   
>               if (disk->specification == LIBXL_DISK_SPECIFICATION_VIRTIO) {
> -                if (disk->backend_domid != LIBXL_TOOLSTACK_DOMID &&
> -                    !iommu_created) {
> -                    FDT( make_xen_iommu_node(gc, fdt) );
> -                    iommu_created = true;
> -                }
> +                if (disk->backend_domid != LIBXL_TOOLSTACK_DOMID)
> +                    iommu_needed = true;
>   
>                   FDT( make_virtio_mmio_node(gc, fdt, disk->base, disk->irq,
>                                              disk->backend_domid) );
>               }
>           }
>   
> +        /*
> +         * The iommu node should be created only once for all virtio-mmio
> +         * devices.
> +         */
> +        if (iommu_needed)
> +            FDT( make_xen_iommu_node(gc, fdt) );
> +
>           if (pfdt)
>               FDT( copy_partial_fdt(gc, fdt, pfdt) );
>   

-- 
Regards,

Oleksandr Tyshchenko