github.com/SagerNet/gvisor@v0.0.0-20210707092255-7731c139d75c/pkg/sentry/platform/kvm/kvm_arm64_unsafe.go (about) 1 // Copyright 2019 The gVisor Authors. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 // +build arm64 16 17 package kvm 18 19 import ( 20 "fmt" 21 22 "golang.org/x/sys/unix" 23 ) 24 25 var ( 26 runDataSize int 27 hasGuestPCID bool 28 ) 29 30 func updateSystemValues(fd int) error { 31 // Extract the mmap size. 32 sz, _, errno := unix.RawSyscall(unix.SYS_IOCTL, uintptr(fd), _KVM_GET_VCPU_MMAP_SIZE, 0) 33 if errno != 0 { 34 return fmt.Errorf("getting VCPU mmap size: %v", errno) 35 } 36 // Save the data. 37 runDataSize = int(sz) 38 hasGuestPCID = true 39 40 // Success. 41 return nil 42 }