[PART1 RFC v3 02/12] KVM: x86: Introducing kvm_x86_ops VM init/uninit hooks

[Suravee Suthikulpanit]

Adding function pointers in struct kvm_x86_ops for processor-specific
layer to provide hooks for when KVM initialize and un-initialize VM.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com>
---
 arch/x86/include/asm/kvm_host.h |  3 +++
 arch/x86/kvm/x86.c              | 10 +++++++++-
 virt/kvm/kvm_main.c             |  8 ++++----
 3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 44adbb8..4b0dd0f 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -828,6 +828,9 @@ struct kvm_x86_ops {
        bool (*cpu_has_high_real_mode_segbase)(void);
        void (*cpuid_update)(struct kvm_vcpu *vcpu);
 
+       int (*vm_init)(struct kvm *kvm);
+       void (*vm_uninit)(struct kvm *kvm);
+
        /* Create, but do not attach this VCPU */
        struct kvm_vcpu *(*vcpu_create)(struct kvm *kvm, unsigned id);
        void (*vcpu_free)(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 429c3f5..4d2961d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7700,6 +7700,8 @@ void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu)
 
 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 {
+       int ret = 0;
+
        if (type)
                return -EINVAL;
 
@@ -7724,7 +7726,10 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
        INIT_DELAYED_WORK(&kvm->arch.kvmclock_update_work, kvmclock_update_fn);
        INIT_DELAYED_WORK(&kvm->arch.kvmclock_sync_work, kvmclock_sync_fn);
 
-       return 0;
+       if (kvm_x86_ops->vm_init)
+               ret = kvm_x86_ops->vm_init(kvm);
+
+       return ret;
 }
 
 static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu)
@@ -7751,6 +7756,9 @@ static void kvm_free_vcpus(struct kvm *kvm)
        kvm_for_each_vcpu(i, vcpu, kvm)
                kvm_arch_vcpu_free(vcpu);
 
+       if (kvm_x86_ops->vm_uninit)
+               kvm_x86_ops->vm_uninit(kvm);
+
        mutex_lock(&kvm->lock);
        for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
                kvm->vcpus[i] = NULL;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 1ca0258..5460325 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -536,10 +536,6 @@ static struct kvm *kvm_create_vm(unsigned long type)
        if (!kvm)
                return ERR_PTR(-ENOMEM);
 
-       r = kvm_arch_init_vm(kvm, type);
-       if (r)
-               goto out_err_no_disable;
-
        r = hardware_enable_all();
        if (r)
                goto out_err_no_disable;
@@ -578,6 +574,10 @@ static struct kvm *kvm_create_vm(unsigned long type)
        atomic_set(&kvm->users_count, 1);
        INIT_LIST_HEAD(&kvm->devices);
 
+       r = kvm_arch_init_vm(kvm, type);
+       if (r)
+               goto out_err;
+
        r = kvm_init_mmu_notifier(kvm);
        if (r)
                goto out_err;
-- 
1.9.1