gvisor/pkg/sentry/syscalls/linux/sys_sysinfo.go

44 lines
1.4 KiB
Go

// Copyright 2018 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.
package linux
import (
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/sentry/arch"
"gvisor.dev/gvisor/pkg/sentry/kernel"
"gvisor.dev/gvisor/pkg/sentry/usage"
)
// Sysinfo implements the sysinfo syscall as described in man 2 sysinfo.
func Sysinfo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
addr := args[0].Pointer()
mf := t.Kernel().MemoryFile()
mf.UpdateUsage()
_, totalUsage := usage.MemoryAccounting.Copy()
totalSize := usage.TotalMemory(mf.TotalSize(), totalUsage)
// Only a subset of the fields in sysinfo_t make sense to return.
si := linux.Sysinfo{
Procs: uint16(len(t.PIDNamespace().Tasks())),
Uptime: t.Kernel().MonotonicClock().Now().Seconds(),
TotalRAM: totalSize,
FreeRAM: totalSize - totalUsage,
Unit: 1,
}
_, err := t.CopyOut(addr, si)
return 0, nil, err
}