1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
// 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 vfs2
import (
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/sentry/arch"
"gvisor.dev/gvisor/pkg/sentry/fsimpl/timerfd"
"gvisor.dev/gvisor/pkg/sentry/kernel"
ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time"
"gvisor.dev/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
}
// Timerfds aren't writable per se (their implementation of Write just
// returns EINVAL), but they are "opened for writing", which is necessary
// to actually reach said implementation of Write.
fileFlags := uint32(linux.O_RDWR)
if flags&linux.TFD_NONBLOCK != 0 {
fileFlags |= linux.O_NONBLOCK
}
var clock ktime.Clock
switch clockID {
case linux.CLOCK_REALTIME:
clock = t.Kernel().RealtimeClock()
case linux.CLOCK_MONOTONIC, linux.CLOCK_BOOTTIME:
clock = t.Kernel().MonotonicClock()
default:
return 0, nil, syserror.EINVAL
}
vfsObj := t.Kernel().VFS()
file, err := timerfd.New(t, vfsObj, clock, fileFlags)
if err != nil {
return 0, nil, err
}
defer file.DecRef(t)
fd, err := t.NewFDFromVFS2(0, file, kernel.FDFlags{
CloseOnExec: flags&linux.TFD_CLOEXEC != 0,
})
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 := 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
}
file := t.GetFileVFS2(fd)
if file == nil {
return 0, nil, syserror.EBADF
}
defer file.DecRef(t)
tfd, ok := file.Impl().(*timerfd.TimerFileDescription)
if !ok {
return 0, nil, syserror.EINVAL
}
var newVal linux.Itimerspec
if _, err := newVal.CopyIn(t, newValAddr); err != nil {
return 0, nil, err
}
newS, err := ktime.SettingFromItimerspec(newVal, flags&linux.TFD_TIMER_ABSTIME != 0, tfd.Clock())
if err != nil {
return 0, nil, err
}
tm, oldS := tfd.SetTime(newS)
if oldValAddr != 0 {
oldVal := ktime.ItimerspecFromSetting(tm, oldS)
if _, err := oldVal.CopyOut(t, oldValAddr); err != nil {
return 0, nil, err
}
}
return 0, nil, nil
}
// TimerfdGettime implements Linux syscall timerfd_gettime(2).
func TimerfdGettime(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
fd := args[0].Int()
curValAddr := args[1].Pointer()
file := t.GetFileVFS2(fd)
if file == nil {
return 0, nil, syserror.EBADF
}
defer file.DecRef(t)
tfd, ok := file.Impl().(*timerfd.TimerFileDescription)
if !ok {
return 0, nil, syserror.EINVAL
}
tm, s := tfd.GetTime()
curVal := ktime.ItimerspecFromSetting(tm, s)
_, err := curVal.CopyOut(t, curValAddr)
return 0, nil, err
}
|
