From 5881f73757cc3dbada878e67c119a801ed0f9a07 Mon Sep 17 00:00:00 2001 From: Suravee Suthikulpanit Date: Tue, 23 Aug 2016 13:52:42 -0500 Subject: [PATCH] svm: Introduce AMD IOMMU avic_ga_log_notifier MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This patch introduces avic_ga_log_notifier, which will be called by IOMMU driver whenever it handles the Guest vAPIC (GA) log entry. Reviewed-by: Radim Krčmář Signed-off-by: Suravee Suthikulpanit Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/svm.c | 70 ++++++++++++++++++++++++++++++++- 2 files changed, 69 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index d36176bb1b6d..4c738c206be3 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -785,6 +785,7 @@ struct kvm_arch { u32 ldr_mode; struct page *avic_logical_id_table_page; struct page *avic_physical_id_table_page; + struct hlist_node hnode; bool x2apic_format; bool x2apic_broadcast_quirk_disabled; diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 27e37d8044b3..0a9e43b2bd26 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -34,6 +34,8 @@ #include #include #include +#include +#include #include #include @@ -945,6 +947,55 @@ static void svm_disable_lbrv(struct vcpu_svm *svm) set_msr_interception(msrpm, MSR_IA32_LASTINTTOIP, 0, 0); } +/* Note: + * This hash table is used to map VM_ID to a struct kvm_arch, + * when handling AMD IOMMU GALOG notification to schedule in + * a particular vCPU. + */ +#define SVM_VM_DATA_HASH_BITS 8 +DECLARE_HASHTABLE(svm_vm_data_hash, SVM_VM_DATA_HASH_BITS); +static spinlock_t svm_vm_data_hash_lock; + +/* Note: + * This function is called from IOMMU driver to notify + * SVM to schedule in a particular vCPU of a particular VM. + */ +static int avic_ga_log_notifier(u32 ga_tag) +{ + unsigned long flags; + struct kvm_arch *ka = NULL; + struct kvm_vcpu *vcpu = NULL; + u32 vm_id = AVIC_GATAG_TO_VMID(ga_tag); + u32 vcpu_id = AVIC_GATAG_TO_VCPUID(ga_tag); + + pr_debug("SVM: %s: vm_id=%#x, vcpu_id=%#x\n", __func__, vm_id, vcpu_id); + + spin_lock_irqsave(&svm_vm_data_hash_lock, flags); + hash_for_each_possible(svm_vm_data_hash, ka, hnode, vm_id) { + struct kvm *kvm = container_of(ka, struct kvm, arch); + struct kvm_arch *vm_data = &kvm->arch; + + if (vm_data->avic_vm_id != vm_id) + continue; + vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id); + break; + } + spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags); + + if (!vcpu) + return 0; + + /* Note: + * At this point, the IOMMU should have already set the pending + * bit in the vAPIC backing page. So, we just need to schedule + * in the vcpu. + */ + if (vcpu->mode == OUTSIDE_GUEST_MODE) + kvm_vcpu_wake_up(vcpu); + + return 0; +} + static __init int svm_hardware_setup(void) { int cpu; @@ -1003,10 +1054,15 @@ static __init int svm_hardware_setup(void) if (avic) { if (!npt_enabled || !boot_cpu_has(X86_FEATURE_AVIC) || - !IS_ENABLED(CONFIG_X86_LOCAL_APIC)) + !IS_ENABLED(CONFIG_X86_LOCAL_APIC)) { avic = false; - else + } else { pr_info("AVIC enabled\n"); + + hash_init(svm_vm_data_hash); + spin_lock_init(&svm_vm_data_hash_lock); + amd_iommu_register_ga_log_notifier(&avic_ga_log_notifier); + } } return 0; @@ -1327,6 +1383,7 @@ static inline int avic_free_vm_id(int id) static void avic_vm_destroy(struct kvm *kvm) { + unsigned long flags; struct kvm_arch *vm_data = &kvm->arch; avic_free_vm_id(vm_data->avic_vm_id); @@ -1335,10 +1392,15 @@ static void avic_vm_destroy(struct kvm *kvm) __free_page(vm_data->avic_logical_id_table_page); if (vm_data->avic_physical_id_table_page) __free_page(vm_data->avic_physical_id_table_page); + + spin_lock_irqsave(&svm_vm_data_hash_lock, flags); + hash_del(&vm_data->hnode); + spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags); } static int avic_vm_init(struct kvm *kvm) { + unsigned long flags; int err = -ENOMEM; struct kvm_arch *vm_data = &kvm->arch; struct page *p_page; @@ -1367,6 +1429,10 @@ static int avic_vm_init(struct kvm *kvm) vm_data->avic_logical_id_table_page = l_page; clear_page(page_address(l_page)); + spin_lock_irqsave(&svm_vm_data_hash_lock, flags); + hash_add(svm_vm_data_hash, &vm_data->hnode, vm_data->avic_vm_id); + spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags); + return 0; free_avic: -- 2.20.1