From 5082219b6a61cab585765a2ce4cd2a1f2f15dcdc Mon Sep 17 00:00:00 2001 From: Filippo Sironi Date: Thu, 31 Aug 2017 10:58:11 +0200 Subject: [PATCH] iommu/vt-d: Don't be too aggressive when clearing one context entry 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 Cc: David Woodhouse Cc: David Woodhouse Cc: Joerg Roedel Cc: Jacob Pan Cc: iommu@lists.linux-foundation.org Cc: linux-kernel@vger.kernel.org Acked-by: David Woodhouse Signed-off-by: Joerg Roedel --- drivers/iommu/intel-iommu.c | 42 +++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 18 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 695f54ad07cc..5b112b6a2c9c 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -974,20 +974,6 @@ static int device_context_mapped(struct intel_iommu *iommu, u8 bus, u8 devfn) return ret; } -static void clear_context_table(struct intel_iommu *iommu, u8 bus, u8 devfn) -{ - struct context_entry *context; - unsigned long flags; - - spin_lock_irqsave(&iommu->lock, flags); - context = iommu_context_addr(iommu, bus, devfn, 0); - if (context) { - context_clear_entry(context); - __iommu_flush_cache(iommu, context, sizeof(*context)); - } - spin_unlock_irqrestore(&iommu->lock, flags); -} - static void free_context_table(struct intel_iommu *iommu) { int i; @@ -2361,13 +2347,33 @@ 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; - 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); + spin_lock_irqsave(&iommu->lock, flags); + context = iommu_context_addr(iommu, bus, devfn, 0); + if (!context) { + spin_unlock_irqrestore(&iommu->lock, flags); + return; + } + did_old = context_domain_id(context); + context_clear_entry(context); + __iommu_flush_cache(iommu, context, sizeof(*context)); + spin_unlock_irqrestore(&iommu->lock, flags); + 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)