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
128
129
130
131
132
133
134
135
136
137
138
139
|
// Copyright 2023 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 tpuproxy
import (
"path/filepath"
"strconv"
"golang.org/x/sys/unix"
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/devutil"
"gvisor.dev/gvisor/pkg/errors/linuxerr"
"gvisor.dev/gvisor/pkg/fdnotifier"
"gvisor.dev/gvisor/pkg/log"
"gvisor.dev/gvisor/pkg/sentry/vfs"
"gvisor.dev/gvisor/pkg/sync"
)
const (
// VFIO_MINOR is the VFIO minor number from include/linux/miscdevice.h.
VFIO_MINOR = 196
// VFIOPath is the path to a VFIO device, it is usually used to
// construct a VFIO container.
VFIOPath = "/dev/vfio/vfio"
tpuDeviceGroupName = "vfio"
vfioDeviceGroupName = "vfio"
)
// device implements TPU's vfs.Device for /dev/vfio/[0-9]+
//
// +stateify savable
type tpuDevice struct {
mu sync.Mutex
// minor is the device minor number.
minor uint32
// num is the number of the device in the dev filesystem (e.g /dev/vfio/0).
num uint32
}
// Open implements vfs.Device.Open.
func (dev *tpuDevice) Open(ctx context.Context, mnt *vfs.Mount, d *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) {
devClient := devutil.GoferClientFromContext(ctx)
if devClient == nil {
log.Warningf("devutil.CtxDevGoferClient is not set")
return nil, linuxerr.ENOENT
}
dev.mu.Lock()
defer dev.mu.Unlock()
devName := filepath.Join("vfio", strconv.Itoa(int(dev.num)))
hostFD, err := devClient.OpenAt(ctx, devName, opts.Flags)
if err != nil {
ctx.Warningf("tpuDevice: failed to open host %s: %v", devName, err)
return nil, err
}
fd := &tpuFD{
hostFD: int32(hostFD),
device: dev,
}
if err := fd.vfsfd.Init(fd, opts.Flags, mnt, d, &vfs.FileDescriptionOptions{
UseDentryMetadata: true,
}); err != nil {
unix.Close(hostFD)
return nil, err
}
if err := fdnotifier.AddFD(int32(hostFD), &fd.queue); err != nil {
unix.Close(hostFD)
return nil, err
}
fd.memmapFile.fd = fd
return &fd.vfsfd, nil
}
// device implements vfs.Device for /dev/vfio/vfio.
type vfioDevice struct{}
// Open implements vfs.Device.Open.
func (dev *vfioDevice) Open(ctx context.Context, mnt *vfs.Mount, d *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) {
client := devutil.GoferClientFromContext(ctx)
if client == nil {
log.Warningf("devutil.CtxDevGoferClient is not set")
return nil, linuxerr.ENOENT
}
name := filepath.Join("vfio", filepath.Base(VFIOPath))
hostFD, err := client.OpenAt(ctx, name, opts.Flags)
if err != nil {
ctx.Warningf("failed to open host file %s: %v", name, err)
return nil, err
}
fd := &vfioFD{
hostFD: int32(hostFD),
device: dev,
}
if err := fd.vfsfd.Init(fd, opts.Flags, mnt, d, &vfs.FileDescriptionOptions{
UseDentryMetadata: true,
}); err != nil {
unix.Close(hostFD)
return nil, err
}
if err := fdnotifier.AddFD(int32(hostFD), &fd.queue); err != nil {
unix.Close(hostFD)
return nil, err
}
fd.memmapFile.fd = fd
return &fd.vfsfd, nil
}
// RegisterTPUDevice registers devices implemented by this package in vfsObj.
func RegisterTPUDevice(vfsObj *vfs.VirtualFilesystem, minor, deviceNum uint32) error {
return vfsObj.RegisterDevice(vfs.CharDevice, linux.VFIO_MAJOR, minor, &tpuDevice{
minor: minor,
num: deviceNum,
}, &vfs.RegisterDeviceOptions{
GroupName: tpuDeviceGroupName,
})
}
// RegisterVfioDevice registers VFIO devices that are implemented by this package in vfsObj.
func RegisterVfioDevice(vfsObj *vfs.VirtualFilesystem) error {
return vfsObj.RegisterDevice(vfs.CharDevice, linux.MISC_MAJOR, VFIO_MINOR, &vfioDevice{}, &vfs.RegisterDeviceOptions{
GroupName: vfioDeviceGroupName,
})
}
|
