github.com/ttpreport/gvisor-ligolo@v0.0.0-20240123134145-a858404967ba/pkg/sentry/fsimpl/tmpfs/device_file.go (about)

     1  // Copyright 2020 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package tmpfs
    16  
    17  import (
    18  	"fmt"
    19  
    20  	"github.com/ttpreport/gvisor-ligolo/pkg/abi/linux"
    21  	"github.com/ttpreport/gvisor-ligolo/pkg/atomicbitops"
    22  	"github.com/ttpreport/gvisor-ligolo/pkg/sentry/kernel/auth"
    23  	"github.com/ttpreport/gvisor-ligolo/pkg/sentry/vfs"
    24  )
    25  
    26  // +stateify savable
    27  type deviceFile struct {
    28  	inode inode
    29  	kind  vfs.DeviceKind
    30  	major uint32
    31  	minor uint32
    32  }
    33  
    34  func (fs *filesystem) newDeviceFile(kuid auth.KUID, kgid auth.KGID, mode linux.FileMode, kind vfs.DeviceKind, major, minor uint32, parentDir *directory) *inode {
    35  	file := &deviceFile{
    36  		kind:  kind,
    37  		major: major,
    38  		minor: minor,
    39  	}
    40  	switch kind {
    41  	case vfs.BlockDevice:
    42  		mode |= linux.S_IFBLK
    43  	case vfs.CharDevice:
    44  		mode |= linux.S_IFCHR
    45  	default:
    46  		panic(fmt.Sprintf("invalid DeviceKind: %v", kind))
    47  	}
    48  	file.inode.init(file, fs, kuid, kgid, mode, parentDir)
    49  	file.inode.nlink = atomicbitops.FromUint32(1) // from parent directory
    50  	return &file.inode
    51  }