On Mon, Mar 07, 2016 at 02:41:12PM +1100, Alexey Kardashevskiy wrote:
> In real mode, TCE tables are invalidated using different
> cache-inhibited store instructions which is different from
> the virtual mode.
>
> This defines and implements exchange_rm() callback. This does not
> define set_rm/clear_rm/flush_rm callbacks as there is no user for those -
> exchange/exchange_rm are only to be used by KVM for VFIO.
>
> The exchange_rm callback is defined for IODA1/IODA2 powernv platforms.
>
> This replaces list_for_each_entry_rcu with its lockless version as
> from now on pnv_pci_ioda2_tce_invalidate() can be called in
> the real mode too.
[snip]
> @@ -1062,6 +1062,21 @@ void iommu_release_ownership(struct iommu_table *tbl)
> }
> EXPORT_SYMBOL_GPL(iommu_release_ownership);
>
> +long iommu_tce_xchg_rm(struct iommu_table *tbl, unsigned long entry,
> + unsigned long *hpa, enum dma_data_direction *direction)
> +{
> + long ret;
> +
> + ret = tbl->it_ops->exchange_rm(tbl, entry, hpa, direction);
> +
> + if (!ret && ((*direction == DMA_FROM_DEVICE) ||
> + (*direction == DMA_BIDIRECTIONAL)))
> + SetPageDirty(realmode_pfn_to_page(*hpa >> PAGE_SHIFT));
realmode_pfn_to_page can fail and return NULL, can't it? You need to
handle that situation somehow.
Paul.
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
