diff options
Diffstat (limited to 'pkg/sentry/syscalls/linux/sys_timerfd.go')
-rw-r--r-- | pkg/sentry/syscalls/linux/sys_timerfd.go | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/pkg/sentry/syscalls/linux/sys_timerfd.go b/pkg/sentry/syscalls/linux/sys_timerfd.go new file mode 100644 index 000000000..cb81d42b9 --- /dev/null +++ b/pkg/sentry/syscalls/linux/sys_timerfd.go @@ -0,0 +1,135 @@ +// Copyright 2018 Google Inc. +// +// 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.googlesource.com/gvisor/pkg/abi/linux" + "gvisor.googlesource.com/gvisor/pkg/sentry/arch" + "gvisor.googlesource.com/gvisor/pkg/sentry/fs" + "gvisor.googlesource.com/gvisor/pkg/sentry/fs/timerfd" + "gvisor.googlesource.com/gvisor/pkg/sentry/kernel" + "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/kdefs" + ktime "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/time" + "gvisor.googlesource.com/gvisor/pkg/syserror" +) + +// TimerfdCreate implements Linux syscall timerfd_create(2). +func TimerfdCreate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + clockID := args[0].Int() + flags := args[1].Int() + + if flags&^(linux.TFD_CLOEXEC|linux.TFD_NONBLOCK) != 0 { + return 0, nil, syserror.EINVAL + } + + var c ktime.Clock + switch clockID { + case linux.CLOCK_REALTIME: + c = t.Kernel().RealtimeClock() + case linux.CLOCK_MONOTONIC: + c = t.Kernel().MonotonicClock() + default: + return 0, nil, syserror.EINVAL + } + f := timerfd.NewFile(t, c) + defer f.DecRef() + f.SetFlags(fs.SettableFileFlags{ + NonBlocking: flags&linux.TFD_NONBLOCK != 0, + }) + + fd, err := t.FDMap().NewFDFrom(0, f, kernel.FDFlags{ + CloseOnExec: flags&linux.TFD_CLOEXEC != 0, + }, t.ThreadGroup().Limits()) + if err != nil { + return 0, nil, err + } + + return uintptr(fd), nil, nil +} + +// TimerfdSettime implements Linux syscall timerfd_settime(2). +func TimerfdSettime(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := kdefs.FD(args[0].Int()) + flags := args[1].Int() + newValAddr := args[2].Pointer() + oldValAddr := args[3].Pointer() + + if flags&^(linux.TFD_TIMER_ABSTIME) != 0 { + return 0, nil, syserror.EINVAL + } + + f := t.FDMap().GetFile(fd) + if f == nil { + return 0, nil, syserror.EBADF + } + defer f.DecRef() + + tf, ok := f.FileOperations.(*timerfd.TimerOperations) + if !ok { + return 0, nil, syserror.EINVAL + } + + var newVal linux.Itimerspec + if _, err := t.CopyIn(newValAddr, &newVal); err != nil { + return 0, nil, err + } + var s ktime.Setting + var err error + if flags&linux.TFD_TIMER_ABSTIME != 0 { + s, err = ktime.SettingFromAbsSpec(ktime.FromTimespec(newVal.Value), + newVal.Interval.ToDuration()) + } else { + s, err = ktime.SettingFromSpec(newVal.Value.ToDuration(), + newVal.Interval.ToDuration(), tf.Clock()) + } + if err != nil { + return 0, nil, err + } + valueNS, intervalNS := ktime.SpecFromSetting(tf.SetTime(s)) + if oldValAddr == 0 { + return 0, nil, nil + } + oldVal := linux.Itimerspec{ + Interval: linux.DurationToTimespec(intervalNS), + Value: linux.DurationToTimespec(valueNS), + } + _, err = t.CopyOut(oldValAddr, &oldVal) + return 0, nil, err +} + +// TimerfdGettime implements Linux syscall timerfd_gettime(2). +func TimerfdGettime(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := kdefs.FD(args[0].Int()) + curValAddr := args[1].Pointer() + + f := t.FDMap().GetFile(fd) + if f == nil { + return 0, nil, syserror.EBADF + } + defer f.DecRef() + + tf, ok := f.FileOperations.(*timerfd.TimerOperations) + if !ok { + return 0, nil, syserror.EINVAL + } + + valueNS, intervalNS := ktime.SpecFromSetting(tf.GetTime()) + curVal := linux.Itimerspec{ + Interval: linux.DurationToTimespec(intervalNS), + Value: linux.DurationToTimespec(valueNS), + } + _, err := t.CopyOut(curValAddr, &curVal) + return 0, nil, err +} |