diff options
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 2 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx.c | 3 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 22 | ||||
| -rw-r--r-- | include/linux/kvm_host.h | 19 | ||||
| -rw-r--r-- | virt/kvm/iommu.c | 6 | ||||
| -rw-r--r-- | virt/kvm/vfio.c | 44 |
6 files changed, 92 insertions, 4 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 91b35e4005d3..de388c55e7ec 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -565,6 +565,8 @@ struct kvm_arch { struct list_head assigned_dev_head; struct iommu_domain *iommu_domain; bool iommu_noncoherent; +#define __KVM_HAVE_ARCH_NONCOHERENT_DMA + atomic_t noncoherent_dma_count; 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 727a5e980c43..fabf7421ec18 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -7445,8 +7445,7 @@ 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_noncoherent) + else if (kvm_arch_has_noncoherent_dma(vcpu->kvm)) 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 92ad83e5b132..ec35d09937da 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2718,8 +2718,7 @@ 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_noncoherent; + return kvm_arch_has_noncoherent_dma(vcpu->kvm); } void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) @@ -6998,6 +6997,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) INIT_LIST_HEAD(&kvm->arch.active_mmu_pages); INIT_LIST_HEAD(&kvm->arch.zapped_obsolete_pages); INIT_LIST_HEAD(&kvm->arch.assigned_dev_head); + atomic_set(&kvm->arch.noncoherent_dma_count, 0); /* Reserve bit 0 of irq_sources_bitmap for userspace irq source */ set_bit(KVM_USERSPACE_IRQ_SOURCE_ID, &kvm->arch.irq_sources_bitmap); @@ -7437,6 +7437,24 @@ bool kvm_arch_can_inject_async_page_present(struct kvm_vcpu *vcpu) kvm_x86_ops->interrupt_allowed(vcpu); } +void kvm_arch_register_noncoherent_dma(struct kvm *kvm) +{ + atomic_inc(&kvm->arch.noncoherent_dma_count); +} +EXPORT_SYMBOL_GPL(kvm_arch_register_noncoherent_dma); + +void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm) +{ + atomic_dec(&kvm->arch.noncoherent_dma_count); +} +EXPORT_SYMBOL_GPL(kvm_arch_unregister_noncoherent_dma); + +bool kvm_arch_has_noncoherent_dma(struct kvm *kvm) +{ + return atomic_read(&kvm->arch.noncoherent_dma_count); +} +EXPORT_SYMBOL_GPL(kvm_arch_has_noncoherent_dma); + EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index ed64880e4915..92aae88756db 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -670,6 +670,25 @@ static inline void kvm_arch_free_vm(struct kvm *kvm) } #endif +#ifdef __KVM_HAVE_ARCH_NONCOHERENT_DMA +void kvm_arch_register_noncoherent_dma(struct kvm *kvm); +void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm); +bool kvm_arch_has_noncoherent_dma(struct kvm *kvm); +#else +static inline void kvm_arch_register_noncoherent_dma(struct kvm *kvm) +{ +} + +static inline void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm) +{ +} + +static inline bool kvm_arch_has_noncoherent_dma(struct kvm *kvm) +{ + return false; +} +#endif + static inline wait_queue_head_t *kvm_arch_vcpu_wq(struct kvm_vcpu *vcpu) { #ifdef __KVM_HAVE_ARCH_WQP diff --git a/virt/kvm/iommu.c b/virt/kvm/iommu.c index d32d156a423a..c7d9ce122529 100644 --- a/virt/kvm/iommu.c +++ b/virt/kvm/iommu.c @@ -140,6 +140,9 @@ static int kvm_iommu_map_memslots(struct kvm *kvm) struct kvm_memslots *slots; struct kvm_memory_slot *memslot; + if (kvm->arch.iommu_noncoherent) + kvm_arch_register_noncoherent_dma(kvm); + idx = srcu_read_lock(&kvm->srcu); slots = kvm_memslots(kvm); @@ -327,6 +330,9 @@ static int kvm_iommu_unmap_memslots(struct kvm *kvm) srcu_read_unlock(&kvm->srcu, idx); + if (kvm->arch.iommu_noncoherent) + kvm_arch_unregister_noncoherent_dma(kvm); + return 0; } diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c index 597c258245ea..ca4260e35037 100644 --- a/virt/kvm/vfio.c +++ b/virt/kvm/vfio.c @@ -27,6 +27,7 @@ struct kvm_vfio_group { struct kvm_vfio { struct list_head group_list; struct mutex lock; + bool noncoherent; }; static struct vfio_group *kvm_vfio_group_get_external_user(struct file *filep) @@ -58,6 +59,43 @@ static void kvm_vfio_group_put_external_user(struct vfio_group *vfio_group) symbol_put(vfio_group_put_external_user); } +/* + * Groups can use the same or different IOMMU domains. If the same then + * adding a new group may change the coherency of groups we've previously + * been told about. We don't want to care about any of that so we retest + * each group and bail as soon as we find one that's noncoherent. This + * means we only ever [un]register_noncoherent_dma once for the whole device. + */ +static void kvm_vfio_update_coherency(struct kvm_device *dev) +{ + struct kvm_vfio *kv = dev->private; + bool noncoherent = false; + struct kvm_vfio_group *kvg; + + mutex_lock(&kv->lock); + + list_for_each_entry(kvg, &kv->group_list, node) { + /* + * TODO: We need an interface to check the coherency of + * the IOMMU domain this group is using. For now, assume + * it's always noncoherent. + */ + noncoherent = true; + break; + } + + if (noncoherent != kv->noncoherent) { + kv->noncoherent = noncoherent; + + if (kv->noncoherent) + kvm_arch_register_noncoherent_dma(dev->kvm); + else + kvm_arch_unregister_noncoherent_dma(dev->kvm); + } + + mutex_unlock(&kv->lock); +} + static int kvm_vfio_set_group(struct kvm_device *dev, long attr, u64 arg) { struct kvm_vfio *kv = dev->private; @@ -105,6 +143,8 @@ static int kvm_vfio_set_group(struct kvm_device *dev, long attr, u64 arg) mutex_unlock(&kv->lock); + kvm_vfio_update_coherency(dev); + return 0; case KVM_DEV_VFIO_GROUP_DEL: @@ -140,6 +180,8 @@ static int kvm_vfio_set_group(struct kvm_device *dev, long attr, u64 arg) kvm_vfio_group_put_external_user(vfio_group); + kvm_vfio_update_coherency(dev); + return ret; } @@ -185,6 +227,8 @@ static void kvm_vfio_destroy(struct kvm_device *dev) kfree(kvg); } + kvm_vfio_update_coherency(dev); + kfree(kv); kfree(dev); /* alloc by kvm_ioctl_create_device, free by .destroy */ } |