diff options
Diffstat (limited to 'pkg/sentry/fsimpl/tmpfs/filesystem.go')
| -rw-r--r-- | pkg/sentry/fsimpl/tmpfs/filesystem.go | 712 |
1 files changed, 0 insertions, 712 deletions
diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go deleted file mode 100644 index 75d01b853..000000000 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ /dev/null @@ -1,712 +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 tmpfs - -import ( - "fmt" - - "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/context" - "gvisor.dev/gvisor/pkg/fspath" - "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/vfs" - "gvisor.dev/gvisor/pkg/syserror" -) - -// Sync implements vfs.FilesystemImpl.Sync. -func (fs *filesystem) Sync(ctx context.Context) error { - // All filesystem state is in-memory. - return nil -} - -// stepLocked resolves rp.Component() to an existing file, starting from the -// given directory. -// -// stepLocked is loosely analogous to fs/namei.c:walk_component(). -// -// Preconditions: filesystem.mu must be locked. !rp.Done(). -func stepLocked(rp *vfs.ResolvingPath, d *dentry) (*dentry, error) { - if !d.inode.isDir() { - return nil, syserror.ENOTDIR - } - if err := d.inode.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { - return nil, err - } -afterSymlink: - nextVFSD, err := rp.ResolveComponent(&d.vfsd) - if err != nil { - return nil, err - } - if nextVFSD == nil { - // Since the Dentry tree is the sole source of truth for tmpfs, if it's - // not in the Dentry tree, it doesn't exist. - return nil, syserror.ENOENT - } - next := nextVFSD.Impl().(*dentry) - if symlink, ok := next.inode.impl.(*symlink); ok && rp.ShouldFollowSymlink() { - // TODO(gvisor.dev/issues/1197): Symlink traversals updates - // access time. - if err := rp.HandleSymlink(symlink.target); err != nil { - return nil, err - } - goto afterSymlink // don't check the current directory again - } - rp.Advance() - return next, nil -} - -// walkParentDirLocked resolves all but the last path component of rp to an -// existing directory, starting from the given directory (which is usually -// rp.Start().Impl().(*dentry)). It does not check that the returned directory -// is searchable by the provider of rp. -// -// walkParentDirLocked is loosely analogous to Linux's -// fs/namei.c:path_parentat(). -// -// Preconditions: filesystem.mu must be locked. !rp.Done(). -func walkParentDirLocked(rp *vfs.ResolvingPath, d *dentry) (*dentry, error) { - for !rp.Final() { - next, err := stepLocked(rp, d) - if err != nil { - return nil, err - } - d = next - } - if !d.inode.isDir() { - return nil, syserror.ENOTDIR - } - return d, nil -} - -// resolveLocked resolves rp to an existing file. -// -// resolveLocked is loosely analogous to Linux's fs/namei.c:path_lookupat(). -// -// Preconditions: filesystem.mu must be locked. -func resolveLocked(rp *vfs.ResolvingPath) (*dentry, error) { - d := rp.Start().Impl().(*dentry) - for !rp.Done() { - next, err := stepLocked(rp, d) - if err != nil { - return nil, err - } - d = next - } - if rp.MustBeDir() && !d.inode.isDir() { - return nil, syserror.ENOTDIR - } - return d, nil -} - -// doCreateAt checks that creating a file at rp is permitted, then invokes -// create to do so. -// -// doCreateAt is loosely analogous to a conjunction of Linux's -// fs/namei.c:filename_create() and done_path_create(). -// -// Preconditions: !rp.Done(). For the final path component in rp, -// !rp.ShouldFollowSymlink(). -func (fs *filesystem) doCreateAt(rp *vfs.ResolvingPath, dir bool, create func(parent *dentry, name string) error) error { - fs.mu.Lock() - defer fs.mu.Unlock() - parent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) - if err != nil { - return err - } - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { - return err - } - name := rp.Component() - if name == "." || name == ".." { - return syserror.EEXIST - } - // Call parent.vfsd.Child() instead of stepLocked() or rp.ResolveChild(), - // because if the child exists we want to return EEXIST immediately instead - // of attempting symlink/mount traversal. - if parent.vfsd.Child(name) != nil { - return syserror.EEXIST - } - if !dir && rp.MustBeDir() { - return syserror.ENOENT - } - // In memfs, the only way to cause a dentry to be disowned is by removing - // it from the filesystem, so this check is equivalent to checking if - // parent has been removed. - if parent.vfsd.IsDisowned() { - return syserror.ENOENT - } - mnt := rp.Mount() - if err := mnt.CheckBeginWrite(); err != nil { - return err - } - defer mnt.EndWrite() - return create(parent, name) -} - -// AccessAt implements vfs.Filesystem.Impl.AccessAt. -func (fs *filesystem) AccessAt(ctx context.Context, rp *vfs.ResolvingPath, creds *auth.Credentials, ats vfs.AccessTypes) error { - fs.mu.RLock() - defer fs.mu.RUnlock() - d, err := resolveLocked(rp) - if err != nil { - return err - } - return d.inode.checkPermissions(creds, ats, d.inode.isDir()) -} - -// GetDentryAt implements vfs.FilesystemImpl.GetDentryAt. -func (fs *filesystem) GetDentryAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetDentryOptions) (*vfs.Dentry, error) { - fs.mu.RLock() - defer fs.mu.RUnlock() - d, err := resolveLocked(rp) - if err != nil { - return nil, err - } - if opts.CheckSearchable { - if !d.inode.isDir() { - return nil, syserror.ENOTDIR - } - if err := d.inode.checkPermissions(rp.Credentials(), vfs.MayExec, true /* isDir */); err != nil { - return nil, err - } - } - d.IncRef() - return &d.vfsd, nil -} - -// GetParentDentryAt implements vfs.FilesystemImpl.GetParentDentryAt. -func (fs *filesystem) GetParentDentryAt(ctx context.Context, rp *vfs.ResolvingPath) (*vfs.Dentry, error) { - fs.mu.RLock() - defer fs.mu.RUnlock() - d, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) - if err != nil { - return nil, err - } - d.IncRef() - return &d.vfsd, nil -} - -// LinkAt implements vfs.FilesystemImpl.LinkAt. -func (fs *filesystem) LinkAt(ctx context.Context, rp *vfs.ResolvingPath, vd vfs.VirtualDentry) error { - return fs.doCreateAt(rp, false /* dir */, func(parent *dentry, name string) error { - if rp.Mount() != vd.Mount() { - return syserror.EXDEV - } - d := vd.Dentry().Impl().(*dentry) - if d.inode.isDir() { - return syserror.EPERM - } - if d.inode.nlink == 0 { - return syserror.ENOENT - } - if d.inode.nlink == maxLinks { - return syserror.EMLINK - } - d.inode.incLinksLocked() - child := fs.newDentry(d.inode) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) - return nil - }) -} - -// MkdirAt implements vfs.FilesystemImpl.MkdirAt. -func (fs *filesystem) MkdirAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.MkdirOptions) error { - return fs.doCreateAt(rp, true /* dir */, func(parent *dentry, name string) error { - if parent.inode.nlink == maxLinks { - return syserror.EMLINK - } - parent.inode.incLinksLocked() // from child's ".." - child := fs.newDentry(fs.newDirectory(rp.Credentials(), opts.Mode)) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) - return nil - }) -} - -// MknodAt implements vfs.FilesystemImpl.MknodAt. -func (fs *filesystem) MknodAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.MknodOptions) error { - return fs.doCreateAt(rp, false /* dir */, func(parent *dentry, name string) error { - var childInode *inode - switch opts.Mode.FileType() { - case 0, linux.S_IFREG: - childInode = fs.newRegularFile(rp.Credentials(), opts.Mode) - case linux.S_IFIFO: - childInode = fs.newNamedPipe(rp.Credentials(), opts.Mode) - case linux.S_IFBLK: - childInode = fs.newDeviceFile(rp.Credentials(), opts.Mode, vfs.BlockDevice, opts.DevMajor, opts.DevMinor) - case linux.S_IFCHR: - childInode = fs.newDeviceFile(rp.Credentials(), opts.Mode, vfs.CharDevice, opts.DevMajor, opts.DevMinor) - case linux.S_IFSOCK: - // Not yet supported. - return syserror.EPERM - default: - return syserror.EINVAL - } - child := fs.newDentry(childInode) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) - return nil - }) -} - -// OpenAt implements vfs.FilesystemImpl.OpenAt. -func (fs *filesystem) OpenAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - if opts.Flags&linux.O_TMPFILE != 0 { - // Not yet supported. - return nil, syserror.EOPNOTSUPP - } - - // Handle O_CREAT and !O_CREAT separately, since in the latter case we - // don't need fs.mu for writing. - if opts.Flags&linux.O_CREAT == 0 { - fs.mu.RLock() - defer fs.mu.RUnlock() - d, err := resolveLocked(rp) - if err != nil { - return nil, err - } - return d.open(ctx, rp, &opts, false /* afterCreate */) - } - - mustCreate := opts.Flags&linux.O_EXCL != 0 - start := rp.Start().Impl().(*dentry) - fs.mu.Lock() - defer fs.mu.Unlock() - if rp.Done() { - // Reject attempts to open directories with O_CREAT. - if rp.MustBeDir() { - return nil, syserror.EISDIR - } - if mustCreate { - return nil, syserror.EEXIST - } - return start.open(ctx, rp, &opts, false /* afterCreate */) - } -afterTrailingSymlink: - parent, err := walkParentDirLocked(rp, start) - if err != nil { - return nil, err - } - // Check for search permission in the parent directory. - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayExec, true); err != nil { - return nil, err - } - // Reject attempts to open directories with O_CREAT. - if rp.MustBeDir() { - return nil, syserror.EISDIR - } - name := rp.Component() - if name == "." || name == ".." { - return nil, syserror.EISDIR - } - // Determine whether or not we need to create a file. - child, err := stepLocked(rp, parent) - if err == syserror.ENOENT { - // Already checked for searchability above; now check for writability. - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite, true); err != nil { - return nil, err - } - if err := rp.Mount().CheckBeginWrite(); err != nil { - return nil, err - } - defer rp.Mount().EndWrite() - // Create and open the child. - child := fs.newDentry(fs.newRegularFile(rp.Credentials(), opts.Mode)) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) - return child.open(ctx, rp, &opts, true) - } - if err != nil { - return nil, err - } - // Do we need to resolve a trailing symlink? - if !rp.Done() { - start = parent - goto afterTrailingSymlink - } - // Open existing file. - if mustCreate { - return nil, syserror.EEXIST - } - return child.open(ctx, rp, &opts, false) -} - -func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.OpenOptions, afterCreate bool) (*vfs.FileDescription, error) { - ats := vfs.AccessTypesForOpenFlags(opts) - if !afterCreate { - if err := d.inode.checkPermissions(rp.Credentials(), ats, d.inode.isDir()); err != nil { - return nil, err - } - } - switch impl := d.inode.impl.(type) { - case *regularFile: - var fd regularFileFD - if err := fd.vfsfd.Init(&fd, opts.Flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { - return nil, err - } - if opts.Flags&linux.O_TRUNC != 0 { - if _, err := impl.truncate(0); err != nil { - return nil, err - } - } - return &fd.vfsfd, nil - case *directory: - // Can't open directories writably. - if ats&vfs.MayWrite != 0 { - return nil, syserror.EISDIR - } - var fd directoryFD - if err := fd.vfsfd.Init(&fd, opts.Flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { - return nil, err - } - return &fd.vfsfd, nil - case *symlink: - // Can't open symlinks without O_PATH (which is unimplemented). - return nil, syserror.ELOOP - case *namedPipe: - return newNamedPipeFD(ctx, impl, rp, &d.vfsd, opts.Flags) - case *deviceFile: - return rp.VirtualFilesystem().OpenDeviceSpecialFile(ctx, rp.Mount(), &d.vfsd, impl.kind, impl.major, impl.minor, opts) - default: - panic(fmt.Sprintf("unknown inode type: %T", d.inode.impl)) - } -} - -// ReadlinkAt implements vfs.FilesystemImpl.ReadlinkAt. -func (fs *filesystem) ReadlinkAt(ctx context.Context, rp *vfs.ResolvingPath) (string, error) { - fs.mu.RLock() - defer fs.mu.RUnlock() - d, err := resolveLocked(rp) - if err != nil { - return "", err - } - symlink, ok := d.inode.impl.(*symlink) - if !ok { - return "", syserror.EINVAL - } - return symlink.target, nil -} - -// RenameAt implements vfs.FilesystemImpl.RenameAt. -func (fs *filesystem) RenameAt(ctx context.Context, rp *vfs.ResolvingPath, oldParentVD vfs.VirtualDentry, oldName string, opts vfs.RenameOptions) error { - if opts.Flags != 0 { - // TODO(b/145974740): Support renameat2 flags. - return syserror.EINVAL - } - - // Resolve newParent first to verify that it's on this Mount. - fs.mu.Lock() - defer fs.mu.Unlock() - newParent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) - if err != nil { - return err - } - newName := rp.Component() - if newName == "." || newName == ".." { - return syserror.EBUSY - } - mnt := rp.Mount() - if mnt != oldParentVD.Mount() { - return syserror.EXDEV - } - if err := mnt.CheckBeginWrite(); err != nil { - return err - } - defer mnt.EndWrite() - - oldParent := oldParentVD.Dentry().Impl().(*dentry) - if err := oldParent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { - return err - } - // Call vfs.Dentry.Child() instead of stepLocked() or rp.ResolveChild(), - // because if the existing child is a symlink or mount point then we want - // to rename over it rather than follow it. - renamedVFSD := oldParent.vfsd.Child(oldName) - if renamedVFSD == nil { - return syserror.ENOENT - } - renamed := renamedVFSD.Impl().(*dentry) - if renamed.inode.isDir() { - if renamed == newParent || renamedVFSD.IsAncestorOf(&newParent.vfsd) { - return syserror.EINVAL - } - if oldParent != newParent { - // Writability is needed to change renamed's "..". - if err := renamed.inode.checkPermissions(rp.Credentials(), vfs.MayWrite, true /* isDir */); err != nil { - return err - } - } - } else { - if opts.MustBeDir || rp.MustBeDir() { - return syserror.ENOTDIR - } - } - - if err := newParent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { - return err - } - replacedVFSD := newParent.vfsd.Child(newName) - var replaced *dentry - if replacedVFSD != nil { - replaced = replacedVFSD.Impl().(*dentry) - if replaced.inode.isDir() { - if !renamed.inode.isDir() { - return syserror.EISDIR - } - if replaced.vfsd.HasChildren() { - return syserror.ENOTEMPTY - } - } else { - if rp.MustBeDir() { - return syserror.ENOTDIR - } - if renamed.inode.isDir() { - return syserror.ENOTDIR - } - } - } else { - if renamed.inode.isDir() && newParent.inode.nlink == maxLinks { - return syserror.EMLINK - } - } - if newParent.vfsd.IsDisowned() { - return syserror.ENOENT - } - - // Linux places this check before some of those above; we do it here for - // simplicity, under the assumption that applications are not intentionally - // doing noop renames expecting them to succeed where non-noop renames - // would fail. - if renamedVFSD == replacedVFSD { - return nil - } - vfsObj := rp.VirtualFilesystem() - oldParentDir := oldParent.inode.impl.(*directory) - newParentDir := newParent.inode.impl.(*directory) - mntns := vfs.MountNamespaceFromContext(ctx) - defer mntns.DecRef() - if err := vfsObj.PrepareRenameDentry(mntns, renamedVFSD, replacedVFSD); err != nil { - return err - } - if replaced != nil { - newParentDir.childList.Remove(replaced) - if replaced.inode.isDir() { - newParent.inode.decLinksLocked() // from replaced's ".." - } - replaced.inode.decLinksLocked() - } - oldParentDir.childList.Remove(renamed) - newParentDir.childList.PushBack(renamed) - if renamed.inode.isDir() { - oldParent.inode.decLinksLocked() - newParent.inode.incLinksLocked() - } - // TODO(gvisor.dev/issues/1197): Update timestamps and parent directory - // sizes. - vfsObj.CommitRenameReplaceDentry(renamedVFSD, &newParent.vfsd, newName, replacedVFSD) - return nil -} - -// RmdirAt implements vfs.FilesystemImpl.RmdirAt. -func (fs *filesystem) RmdirAt(ctx context.Context, rp *vfs.ResolvingPath) error { - fs.mu.Lock() - defer fs.mu.Unlock() - parent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) - if err != nil { - return err - } - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { - return err - } - name := rp.Component() - if name == "." { - return syserror.EINVAL - } - if name == ".." { - return syserror.ENOTEMPTY - } - childVFSD := parent.vfsd.Child(name) - if childVFSD == nil { - return syserror.ENOENT - } - child := childVFSD.Impl().(*dentry) - if !child.inode.isDir() { - return syserror.ENOTDIR - } - if childVFSD.HasChildren() { - return syserror.ENOTEMPTY - } - mnt := rp.Mount() - if err := mnt.CheckBeginWrite(); err != nil { - return err - } - defer mnt.EndWrite() - vfsObj := rp.VirtualFilesystem() - mntns := vfs.MountNamespaceFromContext(ctx) - defer mntns.DecRef() - if err := vfsObj.PrepareDeleteDentry(mntns, childVFSD); err != nil { - return err - } - parent.inode.impl.(*directory).childList.Remove(child) - parent.inode.decLinksLocked() // from child's ".." - child.inode.decLinksLocked() - vfsObj.CommitDeleteDentry(childVFSD) - return nil -} - -// SetStatAt implements vfs.FilesystemImpl.SetStatAt. -func (fs *filesystem) SetStatAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.SetStatOptions) error { - fs.mu.RLock() - defer fs.mu.RUnlock() - d, err := resolveLocked(rp) - if err != nil { - return err - } - return d.inode.setStat(ctx, rp.Credentials(), &opts.Stat) -} - -// StatAt implements vfs.FilesystemImpl.StatAt. -func (fs *filesystem) StatAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.StatOptions) (linux.Statx, error) { - fs.mu.RLock() - defer fs.mu.RUnlock() - d, err := resolveLocked(rp) - if err != nil { - return linux.Statx{}, err - } - var stat linux.Statx - d.inode.statTo(&stat) - return stat, nil -} - -// StatFSAt implements vfs.FilesystemImpl.StatFSAt. -func (fs *filesystem) StatFSAt(ctx context.Context, rp *vfs.ResolvingPath) (linux.Statfs, error) { - fs.mu.RLock() - defer fs.mu.RUnlock() - _, err := resolveLocked(rp) - if err != nil { - return linux.Statfs{}, err - } - // TODO(gvisor.dev/issues/1197): Actually implement statfs. - return linux.Statfs{}, syserror.ENOSYS -} - -// SymlinkAt implements vfs.FilesystemImpl.SymlinkAt. -func (fs *filesystem) SymlinkAt(ctx context.Context, rp *vfs.ResolvingPath, target string) error { - return fs.doCreateAt(rp, false /* dir */, func(parent *dentry, name string) error { - child := fs.newDentry(fs.newSymlink(rp.Credentials(), target)) - parent.vfsd.InsertChild(&child.vfsd, name) - parent.inode.impl.(*directory).childList.PushBack(child) - return nil - }) -} - -// UnlinkAt implements vfs.FilesystemImpl.UnlinkAt. -func (fs *filesystem) UnlinkAt(ctx context.Context, rp *vfs.ResolvingPath) error { - fs.mu.Lock() - defer fs.mu.Unlock() - parent, err := walkParentDirLocked(rp, rp.Start().Impl().(*dentry)) - if err != nil { - return err - } - if err := parent.inode.checkPermissions(rp.Credentials(), vfs.MayWrite|vfs.MayExec, true /* isDir */); err != nil { - return err - } - name := rp.Component() - if name == "." || name == ".." { - return syserror.EISDIR - } - childVFSD := parent.vfsd.Child(name) - if childVFSD == nil { - return syserror.ENOENT - } - child := childVFSD.Impl().(*dentry) - if child.inode.isDir() { - return syserror.EISDIR - } - if rp.MustBeDir() { - return syserror.ENOTDIR - } - mnt := rp.Mount() - if err := mnt.CheckBeginWrite(); err != nil { - return err - } - defer mnt.EndWrite() - vfsObj := rp.VirtualFilesystem() - mntns := vfs.MountNamespaceFromContext(ctx) - defer mntns.DecRef() - if err := vfsObj.PrepareDeleteDentry(mntns, childVFSD); err != nil { - return err - } - parent.inode.impl.(*directory).childList.Remove(child) - child.inode.decLinksLocked() - vfsObj.CommitDeleteDentry(childVFSD) - return nil -} - -// ListxattrAt implements vfs.FilesystemImpl.ListxattrAt. -func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) { - fs.mu.RLock() - defer fs.mu.RUnlock() - _, err := resolveLocked(rp) - if err != nil { - return nil, err - } - // TODO(b/127675828): support extended attributes - return nil, syserror.ENOTSUP -} - -// GetxattrAt implements vfs.FilesystemImpl.GetxattrAt. -func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) { - fs.mu.RLock() - defer fs.mu.RUnlock() - _, err := resolveLocked(rp) - if err != nil { - return "", err - } - // TODO(b/127675828): support extended attributes - return "", syserror.ENOTSUP -} - -// SetxattrAt implements vfs.FilesystemImpl.SetxattrAt. -func (fs *filesystem) SetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.SetxattrOptions) error { - fs.mu.RLock() - defer fs.mu.RUnlock() - _, err := resolveLocked(rp) - if err != nil { - return err - } - // TODO(b/127675828): support extended attributes - return syserror.ENOTSUP -} - -// RemovexattrAt implements vfs.FilesystemImpl.RemovexattrAt. -func (fs *filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) error { - fs.mu.RLock() - defer fs.mu.RUnlock() - _, err := resolveLocked(rp) - if err != nil { - return err - } - // TODO(b/127675828): support extended attributes - return syserror.ENOTSUP -} - -// PrependPath implements vfs.FilesystemImpl.PrependPath. -func (fs *filesystem) PrependPath(ctx context.Context, vfsroot, vd vfs.VirtualDentry, b *fspath.Builder) error { - fs.mu.RLock() - defer fs.mu.RUnlock() - return vfs.GenericPrependPath(vfsroot, vd, b) -} |