Add support for device special files to VFS2 tmpfs.

PiperOrigin-RevId: 291471892

1 files changed, 39 insertions, 0 deletions

diff --git a/pkg/sentry/fsimpl/tmpfs/device_file.go b/pkg/sentry/fsimpl/tmpfs/device_file.go
new file mode 100644
index 000000000..84b181b90
--- /dev/null
+++ b/pkg/sentry/fsimpl/tmpfs/device_file.go
@@ -0,0 +1,39 @@
+// Copyright 2020 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 tmpfs
+
+import (
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
+	"gvisor.dev/gvisor/pkg/sentry/vfs"
+)
+
+type deviceFile struct {
+	inode inode
+	kind  vfs.DeviceKind
+	major uint32
+	minor uint32
+}
+
+func (fs *filesystem) newDeviceFile(creds *auth.Credentials, mode linux.FileMode, kind vfs.DeviceKind, major, minor uint32) *inode {
+	file := &deviceFile{
+		kind:  kind,
+		major: major,
+		minor: minor,
+	}
+	file.inode.init(file, fs, creds, mode)
+	file.inode.nlink = 1 // from parent directory
+	return &file.inode
+}