Host VM execute vmptrld(vmcs12) then vmlaunch to launch its guest, while
pKVM need to get corresponding shadow_vcpu_state based on vmcs12 to do
vmptrld emulation (real vmcs page of guest - vmcs02 shall be kept in
shadow_vcpu_state - it will be added in the following patches).
Take use of hash table shadow_vcpu_table to build the mapping between
vmcs12_pa and shadow_vcpu_state. Then pKVM is able to quick find out
shadow_vcpu_state from vmcs12_pa when emulating vmptrld.
Signed-off-by: Jason Chen CJ <jason.cj.chen@xxxxxxxxx>
Signed-off-by: Chuanxiao Dong <chuanxiao.dong@xxxxxxxxx>
---
arch/x86/kvm/vmx/pkvm/hyp/pkvm.c | 47 +++++++++++++++++++++++++++-
arch/x86/kvm/vmx/pkvm/hyp/pkvm_hyp.h | 4 +++
2 files changed, 50 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/pkvm/hyp/pkvm.c b/arch/x86/kvm/vmx/pkvm/hyp/pkvm.c
index b110ac43a792..9efedba2b3c9 100644
--- a/arch/x86/kvm/vmx/pkvm/hyp/pkvm.c
+++ b/arch/x86/kvm/vmx/pkvm/hyp/pkvm.c
@@ -3,6 +3,7 @@
* Copyright (C) 2022 Intel Corporation
*/
+#include <linux/hashtable.h>
#include <pkvm.h>
#include "pkvm_hyp.h"
@@ -26,6 +27,10 @@ static struct shadow_vm_ref shadow_vms_ref[MAX_SHADOW_VMS];
#define SHADOW_VCPU_ARRAY(vm) \
((struct shadow_vcpu_array *)((void *)(vm) + sizeof(struct pkvm_shadow_vm)))
+#define SHADOW_VCPU_HASH_BITS 10
+DEFINE_HASHTABLE(shadow_vcpu_table, SHADOW_VCPU_HASH_BITS);
+static pkvm_spinlock_t shadow_vcpu_table_lock = __PKVM_SPINLOCK_UNLOCKED;
+
static int allocate_shadow_vm_handle(struct pkvm_shadow_vm *vm)
{
struct shadow_vm_ref *vm_ref;
@@ -133,6 +138,37 @@ static void put_shadow_vm(int shadow_vm_handle)
WARN_ON(atomic_dec_if_positive(&vm_ref->refcount) <= 0);
}
+static void add_shadow_vcpu_vmcs12_map(struct shadow_vcpu_state *vcpu)
+{
+ pkvm_spin_lock(&shadow_vcpu_table_lock);
+ hash_add(shadow_vcpu_table, &vcpu->hnode, vcpu->vmcs12_pa);
+ pkvm_spin_unlock(&shadow_vcpu_table_lock);
+}
+
+static void remove_shadow_vcpu_vmcs12_map(struct shadow_vcpu_state *vcpu)
+{
+ pkvm_spin_lock(&shadow_vcpu_table_lock);
+ hash_del(&vcpu->hnode);
+ pkvm_spin_unlock(&shadow_vcpu_table_lock);
+}
+
+s64 find_shadow_vcpu_handle_by_vmcs(unsigned long vmcs12_pa)
+{
+ struct shadow_vcpu_state *shadow_vcpu;
+ s64 handle = -1;
+
+ pkvm_spin_lock(&shadow_vcpu_table_lock);
+ hash_for_each_possible(shadow_vcpu_table, shadow_vcpu, hnode, vmcs12_pa) {
+ if (shadow_vcpu->vmcs12_pa == vmcs12_pa) {
+ handle = shadow_vcpu->shadow_vcpu_handle;
+ break;
+ }
+ }
+ pkvm_spin_unlock(&shadow_vcpu_table_lock);
+
+ return handle;
+}
+
struct shadow_vcpu_state *get_shadow_vcpu(s64 shadow_vcpu_handle)
{
int shadow_vm_handle = to_shadow_vm_handle(shadow_vcpu_handle);
@@ -197,6 +233,8 @@ static s64 attach_shadow_vcpu_to_vm(struct pkvm_shadow_vm *vm,
if (!shadow_vcpu->vm)
return -EINVAL;
+ add_shadow_vcpu_vmcs12_map(shadow_vcpu);
+
pkvm_spin_lock(&vm->lock);
if (vm->created_vcpus == KVM_MAX_VCPUS) {
@@ -241,12 +279,14 @@ detach_shadow_vcpu_from_vm(struct pkvm_shadow_vm *vm, s64 shadow_vcpu_handle)
pkvm_spin_unlock(&vm->lock);
- if (shadow_vcpu)
+ if (shadow_vcpu) {
+ remove_shadow_vcpu_vmcs12_map(shadow_vcpu);
/*
* Paired with the get_shadow_vm when saving the shadow_vm pointer
* during attaching shadow_vcpu.
*/
put_shadow_vm(shadow_vcpu->vm->shadow_vm_handle);
+ }
return shadow_vcpu;
}
@@ -258,6 +298,7 @@ s64 __pkvm_init_shadow_vcpu(struct kvm_vcpu *hvcpu, int shadow_vm_handle,
struct pkvm_shadow_vm *vm;
struct shadow_vcpu_state *shadow_vcpu;
struct x86_exception e;
+ unsigned long vmcs12_va;
s64 shadow_vcpu_handle;
int ret;
@@ -273,6 +314,10 @@ s64 __pkvm_init_shadow_vcpu(struct kvm_vcpu *hvcpu, int shadow_vm_handle,
if (ret < 0)
return -EINVAL;
+ vmcs12_va = (unsigned long)shadow_vcpu->vmx.vmcs01.vmcs;
+ if (gva2gpa(hvcpu, vmcs12_va, (gpa_t *)&shadow_vcpu->vmcs12_pa, 0, &e))
+ return -EINVAL;
+
vm = get_shadow_vm(shadow_vm_handle);
if (!vm)
return -EINVAL;
diff --git a/arch/x86/kvm/vmx/pkvm/hyp/pkvm_hyp.h b/arch/x86/kvm/vmx/pkvm/hyp/pkvm_hyp.h
index f15a49b3be5d..c574831c6d18 100644
--- a/arch/x86/kvm/vmx/pkvm/hyp/pkvm_hyp.h
+++ b/arch/x86/kvm/vmx/pkvm/hyp/pkvm_hyp.h
@@ -21,6 +21,9 @@ struct shadow_vcpu_state {
struct pkvm_shadow_vm *vm;
+ struct hlist_node hnode;
+ unsigned long vmcs12_pa;
+
struct vcpu_vmx vmx;
} __aligned(PAGE_SIZE);
@@ -74,6 +77,7 @@ s64 __pkvm_init_shadow_vcpu(struct kvm_vcpu *hvcpu, int shadow_vm_handle,
unsigned long __pkvm_teardown_shadow_vcpu(s64 shadow_vcpu_handle);
struct shadow_vcpu_state *get_shadow_vcpu(s64 shadow_vcpu_handle);
void put_shadow_vcpu(s64 shadow_vcpu_handle);
+s64 find_shadow_vcpu_handle_by_vmcs(unsigned long vmcs12_pa);
extern struct pkvm_hyp *pkvm_hyp;
--
2.25.1
