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Diffstat (limited to 'pkg/sentry/fsimpl/memfs/directory.go')
-rw-r--r--pkg/sentry/fsimpl/memfs/directory.go187
1 files changed, 0 insertions, 187 deletions
diff --git a/pkg/sentry/fsimpl/memfs/directory.go b/pkg/sentry/fsimpl/memfs/directory.go
deleted file mode 100644
index 0bd82e480..000000000
--- a/pkg/sentry/fsimpl/memfs/directory.go
+++ /dev/null
@@ -1,187 +0,0 @@
-// Copyright 2019 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 memfs
-
-import (
- "gvisor.dev/gvisor/pkg/abi/linux"
- "gvisor.dev/gvisor/pkg/sentry/context"
- "gvisor.dev/gvisor/pkg/sentry/kernel/auth"
- "gvisor.dev/gvisor/pkg/sentry/vfs"
- "gvisor.dev/gvisor/pkg/syserror"
-)
-
-type directory struct {
- inode inode
-
- // childList is a list containing (1) child Dentries and (2) fake Dentries
- // (with inode == nil) that represent the iteration position of
- // directoryFDs. childList is used to support directoryFD.IterDirents()
- // efficiently. childList is protected by filesystem.mu.
- childList dentryList
-}
-
-func (fs *filesystem) newDirectory(creds *auth.Credentials, mode linux.FileMode) *inode {
- dir := &directory{}
- dir.inode.init(dir, fs, creds, mode)
- dir.inode.nlink = 2 // from "." and parent directory or ".." for root
- return &dir.inode
-}
-
-func (i *inode) isDir() bool {
- _, ok := i.impl.(*directory)
- return ok
-}
-
-type directoryFD struct {
- fileDescription
- vfs.DirectoryFileDescriptionDefaultImpl
-
- // Protected by filesystem.mu.
- iter *dentry
- off int64
-}
-
-// Release implements vfs.FileDescriptionImpl.Release.
-func (fd *directoryFD) Release() {
- if fd.iter != nil {
- fs := fd.filesystem()
- dir := fd.inode().impl.(*directory)
- fs.mu.Lock()
- dir.childList.Remove(fd.iter)
- fs.mu.Unlock()
- fd.iter = nil
- }
-}
-
-// IterDirents implements vfs.FileDescriptionImpl.IterDirents.
-func (fd *directoryFD) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback) error {
- fs := fd.filesystem()
- vfsd := fd.vfsfd.VirtualDentry().Dentry()
-
- fs.mu.Lock()
- defer fs.mu.Unlock()
-
- if fd.off == 0 {
- if !cb.Handle(vfs.Dirent{
- Name: ".",
- Type: linux.DT_DIR,
- Ino: vfsd.Impl().(*dentry).inode.ino,
- NextOff: 1,
- }) {
- return nil
- }
- fd.off++
- }
- if fd.off == 1 {
- parentInode := vfsd.ParentOrSelf().Impl().(*dentry).inode
- if !cb.Handle(vfs.Dirent{
- Name: "..",
- Type: parentInode.direntType(),
- Ino: parentInode.ino,
- NextOff: 2,
- }) {
- return nil
- }
- fd.off++
- }
-
- dir := vfsd.Impl().(*dentry).inode.impl.(*directory)
- var child *dentry
- if fd.iter == nil {
- // Start iteration at the beginning of dir.
- child = dir.childList.Front()
- fd.iter = &dentry{}
- } else {
- // Continue iteration from where we left off.
- child = fd.iter.Next()
- dir.childList.Remove(fd.iter)
- }
- for child != nil {
- // Skip other directoryFD iterators.
- if child.inode != nil {
- if !cb.Handle(vfs.Dirent{
- Name: child.vfsd.Name(),
- Type: child.inode.direntType(),
- Ino: child.inode.ino,
- NextOff: fd.off + 1,
- }) {
- dir.childList.InsertBefore(child, fd.iter)
- return nil
- }
- fd.off++
- }
- child = child.Next()
- }
- dir.childList.PushBack(fd.iter)
- return nil
-}
-
-// Seek implements vfs.FileDescriptionImpl.Seek.
-func (fd *directoryFD) Seek(ctx context.Context, offset int64, whence int32) (int64, error) {
- fs := fd.filesystem()
- fs.mu.Lock()
- defer fs.mu.Unlock()
-
- switch whence {
- case linux.SEEK_SET:
- // Use offset as given.
- case linux.SEEK_CUR:
- offset += fd.off
- default:
- return 0, syserror.EINVAL
- }
- if offset < 0 {
- return 0, syserror.EINVAL
- }
-
- // If the offset isn't changing (e.g. due to lseek(0, SEEK_CUR)), don't
- // seek even if doing so might reposition the iterator due to concurrent
- // mutation of the directory. Compare fs/libfs.c:dcache_dir_lseek().
- if fd.off == offset {
- return offset, nil
- }
-
- fd.off = offset
- // Compensate for "." and "..".
- remChildren := int64(0)
- if offset >= 2 {
- remChildren = offset - 2
- }
-
- dir := fd.inode().impl.(*directory)
-
- // Ensure that fd.iter exists and is not linked into dir.childList.
- if fd.iter == nil {
- fd.iter = &dentry{}
- } else {
- dir.childList.Remove(fd.iter)
- }
- // Insert fd.iter before the remChildren'th child, or at the end of the
- // list if remChildren >= number of children.
- child := dir.childList.Front()
- for child != nil {
- // Skip other directoryFD iterators.
- if child.inode != nil {
- if remChildren == 0 {
- dir.childList.InsertBefore(child, fd.iter)
- return offset, nil
- }
- remChildren--
- }
- child = child.Next()
- }
- dir.childList.PushBack(fd.iter)
- return offset, nil
-}