On Mon, 28 Aug 2017 16:16:29 +0200
Filippo Sironi via iommu <io...@lists.linux-foundation.org> wrote:
> Previously, we were invalidating context cache and IOTLB globally when
> clearing one context entry. This is a tad too aggressive.
> Invalidate the context cache and IOTLB for the interested device only.
>
> Signed-off-by: Filippo Sironi <sir...@amazon.de>
> Cc: David Woodhouse <d...@amazon.co.uk>
> Cc: David Woodhouse <dw...@infradead.org>
> Cc: Joerg Roedel <j...@8bytes.org>
> Cc: io...@lists.linux-foundation.org
> Cc: linux-kernel@vger.kernel.org
> ---
> drivers/iommu/intel-iommu.c | 25 ++++++++++++++++++++++---
> 1 file changed, 22 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
> index 3e8636f1220e..4bf3e59b0929 100644
> --- a/drivers/iommu/intel-iommu.c
> +++ b/drivers/iommu/intel-iommu.c
> @@ -2351,13 +2351,32 @@ static inline int domain_pfn_mapping(struct
> dmar_domain *domain, unsigned long i
> static void domain_context_clear_one(struct intel_iommu *iommu, u8
> bus, u8 devfn) {
> + unsigned long flags;
> + struct context_entry *context;
> + u16 did_old;
> +
> if (!iommu)
> return;
>
> + spin_lock_irqsave(&iommu->lock, flags);
> + context = iommu_context_addr(iommu, bus, devfn, 0);
> + if (!context) {
> + spin_unlock_irqrestore(&iommu->lock, flags);
> + return;
> + }
perhaps check with device_context_mapped()?
> + did_old = context_domain_id(context);
> + spin_unlock_irqrestore(&iommu->lock, flags);
> clear_context_table(iommu, bus, devfn);
> - iommu->flush.flush_context(iommu, 0, 0, 0,
> - DMA_CCMD_GLOBAL_INVL);
> - iommu->flush.flush_iotlb(iommu, 0, 0, 0,
> DMA_TLB_GLOBAL_FLUSH);
> + iommu->flush.flush_context(iommu,
> + did_old,
> + (((u16)bus) << 8) | devfn,
> + DMA_CCMD_MASK_NOBIT,
> + DMA_CCMD_DEVICE_INVL);
> + iommu->flush.flush_iotlb(iommu,
> + did_old,
> + 0,
> + 0,
> + DMA_TLB_DSI_FLUSH);
> }
>
> static inline void unlink_domain_info(struct device_domain_info
> *info)
[Jacob Pan]
