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>
This commit is contained in:
Liran Alon
2019-06-16 15:03:10 +03:00
committed by Paolo Bonzini
parent 76e3bcdb61
commit 6ca00dfafd
6 changed files with 122 additions and 85 deletions

View File

@@ -3857,43 +3857,59 @@ Type: vcpu ioctl
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 @@ Type: vcpu ioctl
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