kvm/x86: Convert iommu_flags to iommu_noncoherent

Default to operating in coherent mode.  This simplifies the logic when
we switch to a model of registering and unregistering noncoherent I/O
with KVM.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/ia64/include/asm/kvm_host.h b/arch/ia64/include/asm/kvm_host.h
index 95a3ff9..db95f57 100644 (file)
--- a/arch/ia64/include/asm/kvm_host.h
+++ b/arch/ia64/include/asm/kvm_host.h
@@ -476,7 +476,7 @@ struct kvm_arch {
 
        struct list_head assigned_dev_head;
        struct iommu_domain *iommu_domain;
-       int iommu_flags;
+       bool iommu_noncoherent;
 
        unsigned long irq_sources_bitmap;
        unsigned long irq_states[KVM_IOAPIC_NUM_PINS];

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 5cbf316..91b35e4 100644 (file)
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -564,7 +564,7 @@ struct kvm_arch {
 
        struct list_head assigned_dev_head;
        struct iommu_domain *iommu_domain;
-       int iommu_flags;
+       bool iommu_noncoherent;
        struct kvm_pic *vpic;
        struct kvm_ioapic *vioapic;
        struct kvm_pit *vpit;

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 6850b0f..727a5e9 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -7446,7 +7446,7 @@ static u64 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
        if (is_mmio)
                ret = MTRR_TYPE_UNCACHABLE << VMX_EPT_MT_EPTE_SHIFT;
        else if (vcpu->kvm->arch.iommu_domain &&
-               !(vcpu->kvm->arch.iommu_flags & KVM_IOMMU_CACHE_COHERENCY))
+                vcpu->kvm->arch.iommu_noncoherent)
                ret = kvm_get_guest_memory_type(vcpu, gfn) <<
                      VMX_EPT_MT_EPTE_SHIFT;
        else

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 15f9540..92ad83e 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2719,7 +2719,7 @@ static void wbinvd_ipi(void *garbage)
 static bool need_emulate_wbinvd(struct kvm_vcpu *vcpu)
 {
        return vcpu->kvm->arch.iommu_domain &&
-               !(vcpu->kvm->arch.iommu_flags & KVM_IOMMU_CACHE_COHERENCY);
+              vcpu->kvm->arch.iommu_noncoherent;
 }
 
 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 7beddbd..ed64880 100644 (file)
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -746,9 +746,6 @@ void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
 int kvm_request_irq_source_id(struct kvm *kvm);
 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id);
 
-/* For vcpu->arch.iommu_flags */
-#define KVM_IOMMU_CACHE_COHERENCY      0x1
-
 #ifdef CONFIG_KVM_DEVICE_ASSIGNMENT
 int kvm_iommu_map_pages(struct kvm *kvm, struct kvm_memory_slot *slot);
 void kvm_iommu_unmap_pages(struct kvm *kvm, struct kvm_memory_slot *slot);

diff --git a/virt/kvm/iommu.c b/virt/kvm/iommu.c
index a3b1410..d32d156 100644 (file)
--- a/virt/kvm/iommu.c
+++ b/virt/kvm/iommu.c
@@ -79,7 +79,7 @@ int kvm_iommu_map_pages(struct kvm *kvm, struct kvm_memory_slot *slot)
        flags = IOMMU_READ;
        if (!(slot->flags & KVM_MEM_READONLY))
                flags |= IOMMU_WRITE;
-       if (kvm->arch.iommu_flags & KVM_IOMMU_CACHE_COHERENCY)
+       if (!kvm->arch.iommu_noncoherent)
                flags |= IOMMU_CACHE;
 
 
@@ -158,7 +158,8 @@ int kvm_assign_device(struct kvm *kvm,
 {
        struct pci_dev *pdev = NULL;
        struct iommu_domain *domain = kvm->arch.iommu_domain;
-       int r, last_flags;
+       int r;
+       bool noncoherent;
 
        /* check if iommu exists and in use */
        if (!domain)
@@ -174,15 +175,13 @@ int kvm_assign_device(struct kvm *kvm,
                return r;
        }
 
-       last_flags = kvm->arch.iommu_flags;
-       if (iommu_domain_has_cap(kvm->arch.iommu_domain,
-                                IOMMU_CAP_CACHE_COHERENCY))
-               kvm->arch.iommu_flags |= KVM_IOMMU_CACHE_COHERENCY;
+       noncoherent = !iommu_domain_has_cap(kvm->arch.iommu_domain,
+                                           IOMMU_CAP_CACHE_COHERENCY);
 
        /* Check if need to update IOMMU page table for guest memory */
-       if ((last_flags ^ kvm->arch.iommu_flags) ==
-                       KVM_IOMMU_CACHE_COHERENCY) {
+       if (noncoherent != kvm->arch.iommu_noncoherent) {
                kvm_iommu_unmap_memslots(kvm);
+               kvm->arch.iommu_noncoherent = noncoherent;
                r = kvm_iommu_map_memslots(kvm);
                if (r)
                        goto out_unmap;
@@ -342,6 +341,7 @@ int kvm_iommu_unmap_guest(struct kvm *kvm)
        mutex_lock(&kvm->slots_lock);
        kvm_iommu_unmap_memslots(kvm);
        kvm->arch.iommu_domain = NULL;
+       kvm->arch.iommu_noncoherent = false;
        mutex_unlock(&kvm->slots_lock);
 
        iommu_domain_free(domain);