From 4c25a2c1b90bf785fc2e2f0f0c74a80b3e070d39 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Sun, 10 May 2009 17:16:06 +0100 Subject: [PATCH] intel-iommu: Clean up handling of "caching mode" vs. context flushing. It really doesn't make a lot of sense to have some of the logic to handle caching vs. non-caching mode duplicated in qi_flush_context() and __iommu_flush_context(), while the return value indicates whether the caller should take other action which depends on the same thing. Especially since qi_flush_context() thought it was returning something entirely different anyway. This patch makes qi_flush_context() and __iommu_flush_context() both return void, removes the 'non_present_entry_flush' argument and makes the only call site which _set_ that argument to 1 do the right thing. Signed-off-by: David Woodhouse --- drivers/pci/dmar.c | 13 +++------- drivers/pci/intel-iommu.c | 52 +++++++++++++++---------------------- include/linux/intel-iommu.h | 8 +++--- 3 files changed, 28 insertions(+), 45 deletions(-) diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c index d3d86b749eee..10a071ba3232 100644 --- a/drivers/pci/dmar.c +++ b/drivers/pci/dmar.c @@ -723,23 +723,16 @@ void qi_global_iec(struct intel_iommu *iommu) qi_submit_sync(&desc, iommu); } -int qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm, - u64 type, int non_present_entry_flush) +void qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm, + u64 type) { struct qi_desc desc; - if (non_present_entry_flush) { - if (!cap_caching_mode(iommu->cap)) - return 1; - else - did = 0; - } - desc.low = QI_CC_FM(fm) | QI_CC_SID(sid) | QI_CC_DID(did) | QI_CC_GRAN(type) | QI_CC_TYPE; desc.high = 0; - return qi_submit_sync(&desc, iommu); + qi_submit_sync(&desc, iommu); } int qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr, diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index d6f4ee50924c..9f5d9151edc9 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -857,26 +857,13 @@ static void iommu_flush_write_buffer(struct intel_iommu *iommu) } /* return value determine if we need a write buffer flush */ -static int __iommu_flush_context(struct intel_iommu *iommu, - u16 did, u16 source_id, u8 function_mask, u64 type, - int non_present_entry_flush) +static void __iommu_flush_context(struct intel_iommu *iommu, + u16 did, u16 source_id, u8 function_mask, + u64 type) { u64 val = 0; unsigned long flag; - /* - * In the non-present entry flush case, if hardware doesn't cache - * non-present entry we do nothing and if hardware cache non-present - * entry, we flush entries of domain 0 (the domain id is used to cache - * any non-present entries) - */ - if (non_present_entry_flush) { - if (!cap_caching_mode(iommu->cap)) - return 1; - else - did = 0; - } - switch (type) { case DMA_CCMD_GLOBAL_INVL: val = DMA_CCMD_GLOBAL_INVL; @@ -901,9 +888,6 @@ static int __iommu_flush_context(struct intel_iommu *iommu, dmar_readq, (!(val & DMA_CCMD_ICC)), val); spin_unlock_irqrestore(&iommu->register_lock, flag); - - /* flush context entry will implicitly flush write buffer */ - return 0; } /* return value determine if we need a write buffer flush */ @@ -1428,14 +1412,21 @@ static int domain_context_mapping_one(struct dmar_domain *domain, int segment, context_set_present(context); domain_flush_cache(domain, context, sizeof(*context)); - /* it's a non-present to present mapping */ - if (iommu->flush.flush_context(iommu, id, - (((u16)bus) << 8) | devfn, DMA_CCMD_MASK_NOBIT, - DMA_CCMD_DEVICE_INVL, 1)) - iommu_flush_write_buffer(iommu); - else + /* + * It's a non-present to present mapping. If hardware doesn't cache + * non-present entry we only need to flush the write-buffer. If the + * _does_ cache non-present entries, then it does so in the special + * domain #0, which we have to flush: + */ + if (cap_caching_mode(iommu->cap)) { + iommu->flush.flush_context(iommu, 0, + (((u16)bus) << 8) | devfn, + DMA_CCMD_MASK_NOBIT, + DMA_CCMD_DEVICE_INVL); iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_DSI_FLUSH, 0); - + } else { + iommu_flush_write_buffer(iommu); + } spin_unlock_irqrestore(&iommu->lock, flags); spin_lock_irqsave(&domain->iommu_lock, flags); @@ -1566,7 +1557,7 @@ static void iommu_detach_dev(struct intel_iommu *iommu, u8 bus, u8 devfn) clear_context_table(iommu, bus, devfn); iommu->flush.flush_context(iommu, 0, 0, 0, - DMA_CCMD_GLOBAL_INVL, 0); + DMA_CCMD_GLOBAL_INVL); iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH, 0); } @@ -2104,8 +2095,7 @@ static int __init init_dmars(void) iommu_set_root_entry(iommu); - iommu->flush.flush_context(iommu, 0, 0, 0, DMA_CCMD_GLOBAL_INVL, - 0); + iommu->flush.flush_context(iommu, 0, 0, 0, DMA_CCMD_GLOBAL_INVL); iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH, 0); iommu_disable_protect_mem_regions(iommu); @@ -2721,7 +2711,7 @@ static int init_iommu_hw(void) iommu_set_root_entry(iommu); iommu->flush.flush_context(iommu, 0, 0, 0, - DMA_CCMD_GLOBAL_INVL, 0); + DMA_CCMD_GLOBAL_INVL); iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH, 0); iommu_disable_protect_mem_regions(iommu); @@ -2738,7 +2728,7 @@ static void iommu_flush_all(void) for_each_active_iommu(iommu, drhd) { iommu->flush.flush_context(iommu, 0, 0, 0, - DMA_CCMD_GLOBAL_INVL, 0); + DMA_CCMD_GLOBAL_INVL); iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH, 0); } diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h index 7246971a7feb..f2b94dafbf38 100644 --- a/include/linux/intel-iommu.h +++ b/include/linux/intel-iommu.h @@ -281,8 +281,8 @@ struct ir_table { #endif struct iommu_flush { - int (*flush_context)(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm, - u64 type, int non_present_entry_flush); + void (*flush_context)(struct intel_iommu *iommu, u16 did, u16 sid, + u8 fm, u64 type); int (*flush_iotlb)(struct intel_iommu *iommu, u16 did, u64 addr, unsigned int size_order, u64 type, int non_present_entry_flush); }; @@ -339,8 +339,8 @@ extern void dmar_disable_qi(struct intel_iommu *iommu); extern int dmar_reenable_qi(struct intel_iommu *iommu); extern void qi_global_iec(struct intel_iommu *iommu); -extern int qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, - u8 fm, u64 type, int non_present_entry_flush); +extern void qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, + u8 fm, u64 type); extern int qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr, unsigned int size_order, u64 type, int non_present_entry_flush);