KVM: x86: Modify struct kvm_nested_state to have explicit fields for data
Improve the KVM_{GET,SET}_NESTED_STATE structs by detailing the format
of VMX nested state data in a struct.
In order to avoid changing the ioctl values of
KVM_{GET,SET}_NESTED_STATE, there is a need to preserve
sizeof(struct kvm_nested_state). This is done by defining the data
struct as "data.vmx[0]". It was the most elegant way I found to
preserve struct size while still keeping struct readable and easy to
maintain. It does have a misfortunate side-effect that now it has to be
accessed as "data.vmx[0]" rather than just "data.vmx".
Because we are already modifying these structs, I also modified the
following:
* Define the "format" field values as macros.
* Rename vmcs_pa to vmcs12_pa for better readability.
Signed-off-by: Liran Alon <liran.alon@oracle.com>
[Remove SVM stubs, add KVM_STATE_NESTED_VMX_VMCS12_SIZE. - Paolo]
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index f5616b4..2a4531b 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -3857,43 +3857,59 @@
Parameters: struct kvm_nested_state (in/out)
Returns: 0 on success, -1 on error
Errors:
- E2BIG: the total state size (including the fixed-size part of struct
- kvm_nested_state) exceeds the value of 'size' specified by
+ E2BIG: the total state size exceeds the value of 'size' specified by
the user; the size required will be written into size.
struct kvm_nested_state {
__u16 flags;
__u16 format;
__u32 size;
+
union {
- struct kvm_vmx_nested_state vmx;
- struct kvm_svm_nested_state svm;
+ struct kvm_vmx_nested_state_hdr vmx;
+ struct kvm_svm_nested_state_hdr svm;
+
+ /* Pad the header to 128 bytes. */
__u8 pad[120];
- };
- __u8 data[0];
+ } hdr;
+
+ union {
+ struct kvm_vmx_nested_state_data vmx[0];
+ struct kvm_svm_nested_state_data svm[0];
+ } data;
};
#define KVM_STATE_NESTED_GUEST_MODE 0x00000001
#define KVM_STATE_NESTED_RUN_PENDING 0x00000002
+#define KVM_STATE_NESTED_EVMCS 0x00000004
-#define KVM_STATE_NESTED_SMM_GUEST_MODE 0x00000001
-#define KVM_STATE_NESTED_SMM_VMXON 0x00000002
+#define KVM_STATE_NESTED_FORMAT_VMX 0
+#define KVM_STATE_NESTED_FORMAT_SVM 1
-struct kvm_vmx_nested_state {
+#define KVM_STATE_NESTED_VMX_VMCS_SIZE 0x1000
+
+#define KVM_STATE_NESTED_VMX_SMM_GUEST_MODE 0x00000001
+#define KVM_STATE_NESTED_VMX_SMM_VMXON 0x00000002
+
+struct kvm_vmx_nested_state_hdr {
__u64 vmxon_pa;
- __u64 vmcs_pa;
+ __u64 vmcs12_pa;
struct {
__u16 flags;
} smm;
};
+struct kvm_vmx_nested_state_data {
+ __u8 vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE];
+ __u8 shadow_vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE];
+};
+
This ioctl copies the vcpu's nested virtualization state from the kernel to
userspace.
-The maximum size of the state, including the fixed-size part of struct
-kvm_nested_state, can be retrieved by passing KVM_CAP_NESTED_STATE to
-the KVM_CHECK_EXTENSION ioctl().
+The maximum size of the state can be retrieved by passing KVM_CAP_NESTED_STATE
+to the KVM_CHECK_EXTENSION ioctl().
4.115 KVM_SET_NESTED_STATE
@@ -3903,8 +3919,8 @@
Parameters: struct kvm_nested_state (in)
Returns: 0 on success, -1 on error
-This copies the vcpu's kvm_nested_state struct from userspace to the kernel. For
-the definition of struct kvm_nested_state, see KVM_GET_NESTED_STATE.
+This copies the vcpu's kvm_nested_state struct from userspace to the kernel.
+For the definition of struct kvm_nested_state, see KVM_GET_NESTED_STATE.
4.116 KVM_(UN)REGISTER_COALESCED_MMIO