On 06.07.2022 17:32, Marek Marczykowski-Górecki wrote:
> Add API similar to rmrr= and ivmd= arguments, but in a common code. This
> will allow drivers to register reserved memory regardless of the IOMMU
> vendor.
> The direct reason for this API is xhci-dbc console driver (aka xue),
> that needs to use DMA. But future change may unify command line
> arguments for user-supplied reserved memory, and it may be useful for
> other drivers in the future too.
I take it that I'll understand the purpose of this when making it to
later patches.
> --- a/xen/drivers/passthrough/iommu.c
> +++ b/xen/drivers/passthrough/iommu.c
> @@ -651,6 +651,46 @@ bool_t iommu_has_feature(struct domain *d, enum
> iommu_feature feature)
> return is_iommu_enabled(d) && test_bit(feature, dom_iommu(d)->features);
> }
>
> +#define MAX_EXTRA_RESERVED_RANGES 20
> +struct extra_reserved_range {
> + xen_pfn_t start;
Why not unsigned long?
> + xen_ulong_t nr;
Why not unsigned int or unsigned long?
> + u32 sbdf;
uint32_t please.
All these type related remarks apply elsewhere as well; others
below also apply wherever else applicable.
> +};
> +static unsigned int __initdata nr_extra_reserved_ranges;
> +static struct extra_reserved_range __initdata
> extra_reserved_ranges[MAX_EXTRA_RESERVED_RANGES];
Overly long line.
> +int iommu_add_extra_reserved_device_memory(xen_pfn_t start, xen_ulong_t nr,
> u32 sbdf)
> +{
> + unsigned int idx;
> +
> + if ( nr_extra_reserved_ranges >= MAX_EXTRA_RESERVED_RANGES )
> + return -ENOMEM;
> +
> + idx = nr_extra_reserved_ranges++;
> + extra_reserved_ranges[idx].start = start;
> + extra_reserved_ranges[idx].nr = nr;
> + extra_reserved_ranges[idx].sbdf = sbdf;
> + return 0;
> +}
Blank line please before final return statement.
Jan
