From a540aa56ba3d29084f28710c8b93cc9c3c422943 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Wed, 22 Mar 2017 15:21:48 +1100 Subject: powerpc/powernv/iommu: Add real mode version of iommu_table_ops::exchange() In real mode, TCE tables are invalidated using special cache-inhibited store instructions which are not available in 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. Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/iommu.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'arch/powerpc/kernel/iommu.c') diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c index 5f202a566ec5..685a4767b722 100644 --- a/arch/powerpc/kernel/iommu.c +++ b/arch/powerpc/kernel/iommu.c @@ -1004,6 +1004,31 @@ long iommu_tce_xchg(struct iommu_table *tbl, unsigned long entry, } EXPORT_SYMBOL_GPL(iommu_tce_xchg); +#ifdef CONFIG_PPC_BOOK3S_64 +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))) { + struct page *pg = realmode_pfn_to_page(*hpa >> PAGE_SHIFT); + + if (likely(pg)) { + SetPageDirty(pg); + } else { + tbl->it_ops->exchange_rm(tbl, entry, hpa, direction); + ret = -EFAULT; + } + } + + return ret; +} +EXPORT_SYMBOL_GPL(iommu_tce_xchg_rm); +#endif + int iommu_take_ownership(struct iommu_table *tbl) { unsigned long flags, i, sz = (tbl->it_size + 7) >> 3; -- cgit v1.2.3