gvisor/pkg/sentry/platform/kvm/testutil/testutil_arm64.go

60 lines
1.6 KiB
Go

// Copyright 2019 The gVisor Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// +build arm64
package testutil
import (
"fmt"
"reflect"
"syscall"
)
// SetTestTarget sets the rip appropriately.
func SetTestTarget(regs *syscall.PtraceRegs, fn func()) {
regs.Pc = uint64(reflect.ValueOf(fn).Pointer())
}
// SetTouchTarget sets rax appropriately.
func SetTouchTarget(regs *syscall.PtraceRegs, target *uintptr) {
if target != nil {
regs.Regs[8] = uint64(reflect.ValueOf(target).Pointer())
} else {
regs.Regs[8] = 0
}
}
// RewindSyscall rewinds a syscall RIP.
func RewindSyscall(regs *syscall.PtraceRegs) {
regs.Pc -= 4
}
// SetTestRegs initializes registers to known values.
func SetTestRegs(regs *syscall.PtraceRegs) {
for i := 0; i <= 30; i++ {
regs.Regs[i] = uint64(i) + 1
}
}
// CheckTestRegs checks that registers were twiddled per TwiddleRegs.
func CheckTestRegs(regs *syscall.PtraceRegs, full bool) (err error) {
for i := 0; i <= 30; i++ {
if need := ^uint64(i + 1); regs.Regs[i] != need {
err = addRegisterMismatch(err, fmt.Sprintf("R%d", i), regs.Regs[i], need)
}
}
return
}