From c459611424d8b8396060eb766e23bd0c70c993bc Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Fri, 20 Nov 2009 14:57:32 +0100 Subject: [PATCH] x86/amd-iommu: Add per IOMMU reference counting This patch adds reference counting for protection domains per IOMMU. This allows a smarter TLB flushing strategy. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/amd_iommu_types.h | 2 ++ arch/x86/kernel/amd_iommu.c | 12 +++++++++--- 2 files changed, 11 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h index ab3e7bf1af71..e68b14811380 100644 --- a/arch/x86/include/asm/amd_iommu_types.h +++ b/arch/x86/include/asm/amd_iommu_types.h @@ -238,7 +238,9 @@ struct protection_domain { unsigned long flags; /* flags to find out type of domain */ bool updated; /* complete domain flush required */ unsigned dev_cnt; /* devices assigned to this domain */ + unsigned dev_iommu[MAX_IOMMUS]; /* per-IOMMU reference count */ void *priv; /* private data */ + }; /* diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 7fe28be3b548..8c38f0085403 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -1175,7 +1175,9 @@ static void __attach_device(struct amd_iommu *iommu, /* update DTE entry */ set_dte_entry(devid, domain); - domain->dev_cnt += 1; + /* Do reference counting */ + domain->dev_iommu[iommu->index] += 1; + domain->dev_cnt += 1; /* ready */ spin_unlock(&domain->lock); @@ -1209,6 +1211,9 @@ static void attach_device(struct amd_iommu *iommu, */ static void __detach_device(struct protection_domain *domain, u16 devid) { + struct amd_iommu *iommu = amd_iommu_rlookup_table[devid]; + + BUG_ON(!iommu); /* lock domain */ spin_lock(&domain->lock); @@ -1223,8 +1228,9 @@ static void __detach_device(struct protection_domain *domain, u16 devid) amd_iommu_apply_erratum_63(devid); - /* decrease reference counter */ - domain->dev_cnt -= 1; + /* decrease reference counters */ + domain->dev_iommu[iommu->index] -= 1; + domain->dev_cnt -= 1; /* ready */ spin_unlock(&domain->lock);