github.com/MerlinKodo/gvisor@v0.0.0-20231110090155-957f62ecf90e/pkg/sentry/fsimpl/tmpfs/named_pipe.go (about)

     1  // Copyright 2019 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  	"github.com/MerlinKodo/gvisor/pkg/abi/linux"
    19  	"github.com/MerlinKodo/gvisor/pkg/atomicbitops"
    20  	"github.com/MerlinKodo/gvisor/pkg/sentry/kernel/auth"
    21  	"github.com/MerlinKodo/gvisor/pkg/sentry/kernel/pipe"
    22  )
    23  
    24  // +stateify savable
    25  type namedPipe struct {
    26  	inode inode
    27  
    28  	pipe *pipe.VFSPipe
    29  }
    30  
    31  // Preconditions:
    32  //   - fs.mu must be locked.
    33  //   - rp.Mount().CheckBeginWrite() has been called successfully.
    34  func (fs *filesystem) newNamedPipe(kuid auth.KUID, kgid auth.KGID, mode linux.FileMode, parentDir *directory) *inode {
    35  	file := &namedPipe{pipe: pipe.NewVFSPipe(true /* isNamed */, pipe.DefaultPipeSize)}
    36  	file.inode.init(file, fs, kuid, kgid, linux.S_IFIFO|mode, parentDir)
    37  	file.inode.nlink = atomicbitops.FromUint32(1) // Only the parent has a link.
    38  	return &file.inode
    39  }