v2api: delete (most) fusefrontend v1 files

All the functionality in these files has been reimplemented
for the v2 api. Drop the old files.

1 files changed, 0 insertions, 692 deletions

diff --git a/internal/fusefrontend/fs.go b/internal/fusefrontend/fs.go
deleted file mode 100644
index e8dae9f..0000000
--- a/internal/fusefrontend/fs.go
+++ /dev/null
@@ -1,692 +0,0 @@
-// Package fusefrontend interfaces directly with the go-fuse library.
-package fusefrontend
-
-// FUSE operations on paths
-
-import (
-	"os"
-	"sync"
-	"sync/atomic"
-	"syscall"
-	"time"
-
-	"golang.org/x/sys/unix"
-
-	"github.com/hanwen/go-fuse/v2/fuse"
-	"github.com/hanwen/go-fuse/v2/fuse/nodefs"
-	"github.com/hanwen/go-fuse/v2/fuse/pathfs"
-
-	"github.com/rfjakob/gocryptfs/internal/configfile"
-	"github.com/rfjakob/gocryptfs/internal/contentenc"
-	"github.com/rfjakob/gocryptfs/internal/inomap"
-	"github.com/rfjakob/gocryptfs/internal/nametransform"
-	"github.com/rfjakob/gocryptfs/internal/serialize_reads"
-	"github.com/rfjakob/gocryptfs/internal/syscallcompat"
-	"github.com/rfjakob/gocryptfs/internal/tlog"
-)
-
-// FS implements the go-fuse virtual filesystem interface.
-type FS struct {
-	// Embed pathfs.defaultFileSystem to avoid compile failure when the
-	// pathfs.FileSystem interface gets new functions. defaultFileSystem
-	// provides a no-op implementation for all functions.
-	pathfs.FileSystem
-	args Args // Stores configuration arguments
-	// dirIVLock: Lock()ed if any "gocryptfs.diriv" file is modified
-	// Readers must RLock() it to prevent them from seeing intermediate
-	// states
-	dirIVLock sync.RWMutex
-	// Filename encryption helper
-	nameTransform nametransform.NameTransformer
-	// Content encryption helper
-	contentEnc *contentenc.ContentEnc
-	// This lock is used by openWriteOnlyFile() to block concurrent opens while
-	// it relaxes the permissions on a file.
-	openWriteOnlyLock sync.RWMutex
-	// MitigatedCorruptions is used to report data corruption that is internally
-	// mitigated by ignoring the corrupt item. For example, when OpenDir() finds
-	// a corrupt filename, we still return the other valid filenames.
-	// The corruption is logged to syslog to inform the user,	and in addition,
-	// the corrupt filename is logged to this channel via
-	// reportMitigatedCorruption().
-	// "gocryptfs -fsck" reads from the channel to also catch these transparently-
-	// mitigated corruptions.
-	MitigatedCorruptions chan string
-	// This flag is set to zero each time fs.isFiltered() is called
-	// (uint32 so that it can be reset with CompareAndSwapUint32).
-	// When -idle was used when mounting, idleMonitor() sets it to 1
-	// periodically.
-	IsIdle uint32
-	// dirCache caches directory fds
-	dirCache dirCacheStruct
-	// inoMap translates inode numbers from different devices to unique inode
-	// numbers.
-	inoMap *inomap.InoMap
-}
-
-//var _ pathfs.FileSystem = &FS{} // Verify that interface is implemented.
-
-// NewFS returns a new encrypted FUSE overlay filesystem.
-func NewFS(args Args, c *contentenc.ContentEnc, n nametransform.NameTransformer) *FS {
-	if args.SerializeReads {
-		serialize_reads.InitSerializer()
-	}
-	if len(args.Exclude) > 0 {
-		tlog.Warn.Printf("Forward mode does not support -exclude")
-	}
-	var st syscall.Stat_t
-	err := syscall.Stat(args.Cipherdir, &st)
-	if err != nil {
-		tlog.Warn.Printf("NewFS: could not stat cipherdir: %v", err)
-		st.Dev = 0
-	}
-	return &FS{
-		FileSystem:    pathfs.NewDefaultFileSystem(),
-		args:          args,
-		nameTransform: n,
-		contentEnc:    c,
-		inoMap:        inomap.New(),
-	}
-}
-
-// GetAttr implements pathfs.Filesystem.
-//
-// GetAttr is symlink-safe through use of openBackingDir() and Fstatat().
-func (fs *FS) GetAttr(relPath string, context *fuse.Context) (*fuse.Attr, fuse.Status) {
-	tlog.Debug.Printf("FS.GetAttr(%q)", relPath)
-	if fs.isFiltered(relPath) {
-		return nil, fuse.EPERM
-	}
-	dirfd, cName, err := fs.openBackingDir(relPath)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	var st unix.Stat_t
-	err = syscallcompat.Fstatat(dirfd, cName, &st, unix.AT_SYMLINK_NOFOLLOW)
-	syscall.Close(dirfd)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	a := &fuse.Attr{}
-	st2 := syscallcompat.Unix2syscall(st)
-	fs.inoMap.TranslateStat(&st2)
-	a.FromStat(&st2)
-	if a.IsRegular() {
-		a.Size = fs.contentEnc.CipherSizeToPlainSize(a.Size)
-	} else if a.IsSymlink() {
-		target, _ := fs.Readlink(relPath, context)
-		a.Size = uint64(len(target))
-	}
-	if fs.args.ForceOwner != nil {
-		a.Owner = *fs.args.ForceOwner
-	}
-	return a, fuse.OK
-}
-
-// mangleOpenFlags is used by Create() and Open() to convert the open flags the user
-// wants to the flags we internally use to open the backing file.
-// The returned flags always contain O_NOFOLLOW.
-func (fs *FS) mangleOpenFlags(flags uint32) (newFlags int) {
-	newFlags = int(flags)
-	// Convert WRONLY to RDWR. We always need read access to do read-modify-write cycles.
-	if (newFlags & syscall.O_ACCMODE) == syscall.O_WRONLY {
-		newFlags = newFlags ^ os.O_WRONLY | os.O_RDWR
-	}
-	// We also cannot open the file in append mode, we need to seek back for RMW
-	newFlags = newFlags &^ os.O_APPEND
-	// O_DIRECT accesses must be aligned in both offset and length. Due to our
-	// crypto header, alignment will be off, even if userspace makes aligned
-	// accesses. Running xfstests generic/013 on ext4 used to trigger lots of
-	// EINVAL errors due to missing alignment. Just fall back to buffered IO.
-	newFlags = newFlags &^ syscallcompat.O_DIRECT
-	// Create and Open are two separate FUSE operations, so O_CREAT should not
-	// be part of the open flags.
-	newFlags = newFlags &^ syscall.O_CREAT
-	// We always want O_NOFOLLOW to be safe against symlink races
-	newFlags |= syscall.O_NOFOLLOW
-	return newFlags
-}
-
-// Open - FUSE call. Open already-existing file.
-//
-// Symlink-safe through Openat().
-func (fs *FS) Open(path string, flags uint32, context *fuse.Context) (fuseFile nodefs.File, status fuse.Status) {
-	if fs.isFiltered(path) {
-		return nil, fuse.EPERM
-	}
-	newFlags := fs.mangleOpenFlags(flags)
-	// Taking this lock makes sure we don't race openWriteOnlyFile()
-	fs.openWriteOnlyLock.RLock()
-	defer fs.openWriteOnlyLock.RUnlock()
-	// Symlink-safe open
-	dirfd, cName, err := fs.openBackingDir(path)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	defer syscall.Close(dirfd)
-	fd, err := syscallcompat.Openat(dirfd, cName, newFlags, 0)
-	// Handle a few specific errors
-	if err != nil {
-		if err == syscall.EMFILE {
-			var lim syscall.Rlimit
-			syscall.Getrlimit(syscall.RLIMIT_NOFILE, &lim)
-			tlog.Warn.Printf("Open %q: too many open files. Current \"ulimit -n\": %d", cName, lim.Cur)
-		}
-		if err == syscall.EACCES && (int(flags)&syscall.O_ACCMODE) == syscall.O_WRONLY {
-			return fs.openWriteOnlyFile(dirfd, cName, newFlags)
-		}
-		return nil, fuse.ToStatus(err)
-	}
-	f := os.NewFile(uintptr(fd), cName)
-	return NewFile(f, fs)
-}
-
-// openBackingFile opens the ciphertext file that backs relative plaintext
-// path "relPath". Always adds O_NOFOLLOW to the flags.
-func (fs *FS) openBackingFile(relPath string, flags int) (fd int, err error) {
-	dirfd, cName, err := fs.openBackingDir(relPath)
-	if err != nil {
-		return -1, err
-	}
-	defer syscall.Close(dirfd)
-	return syscallcompat.Openat(dirfd, cName, flags|syscall.O_NOFOLLOW, 0)
-}
-
-// Due to RMW, we always need read permissions on the backing file. This is a
-// problem if the file permissions do not allow reading (i.e. 0200 permissions).
-// This function works around that problem by chmod'ing the file, obtaining a fd,
-// and chmod'ing it back.
-func (fs *FS) openWriteOnlyFile(dirfd int, cName string, newFlags int) (*File, fuse.Status) {
-	woFd, err := syscallcompat.Openat(dirfd, cName, syscall.O_WRONLY|syscall.O_NOFOLLOW, 0)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	defer syscall.Close(woFd)
-	var st syscall.Stat_t
-	err = syscall.Fstat(woFd, &st)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	// The cast to uint32 fixes a build failure on Darwin, where st.Mode is uint16.
-	perms := uint32(st.Mode)
-	// Verify that we don't have read permissions
-	if perms&0400 != 0 {
-		tlog.Warn.Printf("openWriteOnlyFile: unexpected permissions %#o, returning EPERM", perms)
-		return nil, fuse.ToStatus(syscall.EPERM)
-	}
-	// Upgrade the lock to block other Open()s and downgrade again on return
-	fs.openWriteOnlyLock.RUnlock()
-	fs.openWriteOnlyLock.Lock()
-	defer func() {
-		fs.openWriteOnlyLock.Unlock()
-		fs.openWriteOnlyLock.RLock()
-	}()
-	// Relax permissions and revert on return
-	err = syscall.Fchmod(woFd, perms|0400)
-	if err != nil {
-		tlog.Warn.Printf("openWriteOnlyFile: changing permissions failed: %v", err)
-		return nil, fuse.ToStatus(err)
-	}
-	defer func() {
-		err2 := syscall.Fchmod(woFd, perms)
-		if err2 != nil {
-			tlog.Warn.Printf("openWriteOnlyFile: reverting permissions failed: %v", err2)
-		}
-	}()
-	rwFd, err := syscallcompat.Openat(dirfd, cName, newFlags, 0)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	f := os.NewFile(uintptr(rwFd), cName)
-	return NewFile(f, fs)
-}
-
-// Create - FUSE call. Creates a new file.
-//
-// Symlink-safe through the use of Openat().
-func (fs *FS) Create(path string, flags uint32, mode uint32, context *fuse.Context) (nodefs.File, fuse.Status) {
-	if fs.isFiltered(path) {
-		return nil, fuse.EPERM
-	}
-	newFlags := fs.mangleOpenFlags(flags)
-	dirfd, cName, err := fs.openBackingDir(path)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	defer syscall.Close(dirfd)
-	fd := -1
-	// Make sure context is nil if we don't want to preserve the owner
-	if !fs.args.PreserveOwner {
-		context = nil
-	}
-	// Handle long file name
-	if !fs.args.PlaintextNames && nametransform.IsLongContent(cName) {
-		// Create ".name"
-		err = fs.nameTransform.WriteLongNameAt(dirfd, cName, path)
-		if err != nil {
-			return nil, fuse.ToStatus(err)
-		}
-		// Create content
-		fd, err = syscallcompat.OpenatUser(dirfd, cName, newFlags|syscall.O_CREAT|syscall.O_EXCL, mode, context)
-		if err != nil {
-			nametransform.DeleteLongNameAt(dirfd, cName)
-		}
-	} else {
-		// Create content, normal (short) file name
-		fd, err = syscallcompat.OpenatUser(dirfd, cName, newFlags|syscall.O_CREAT|syscall.O_EXCL, mode, context)
-	}
-	if err != nil {
-		// xfstests generic/488 triggers this
-		if err == syscall.EMFILE {
-			var lim syscall.Rlimit
-			syscall.Getrlimit(syscall.RLIMIT_NOFILE, &lim)
-			tlog.Warn.Printf("Create %q: too many open files. Current \"ulimit -n\": %d", cName, lim.Cur)
-		}
-		return nil, fuse.ToStatus(err)
-	}
-	f := os.NewFile(uintptr(fd), cName)
-	return NewFile(f, fs)
-}
-
-// Chmod - FUSE call. Change permissions on "path".
-//
-// Symlink-safe through use of Fchmodat().
-func (fs *FS) Chmod(path string, mode uint32, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	dirfd, cName, err := fs.openBackingDir(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	defer syscall.Close(dirfd)
-	// os.Chmod goes through the "syscallMode" translation function that messes
-	// up the suid and sgid bits. So use a syscall directly.
-	err = syscallcompat.FchmodatNofollow(dirfd, cName, mode)
-	return fuse.ToStatus(err)
-}
-
-// Chown - FUSE call. Change the owner of "path".
-//
-// Symlink-safe through use of Fchownat().
-func (fs *FS) Chown(path string, uid uint32, gid uint32, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	dirfd, cName, err := fs.openBackingDir(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	defer syscall.Close(dirfd)
-	err = syscallcompat.Fchownat(dirfd, cName, int(uid), int(gid), unix.AT_SYMLINK_NOFOLLOW)
-	return fuse.ToStatus(err)
-}
-
-// Mknod - FUSE call. Create a device file.
-//
-// Symlink-safe through use of Mknodat().
-func (fs *FS) Mknod(path string, mode uint32, dev uint32, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	dirfd, cName, err := fs.openBackingDir(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	defer syscall.Close(dirfd)
-	// Make sure context is nil if we don't want to preserve the owner
-	if !fs.args.PreserveOwner {
-		context = nil
-	}
-	// Create ".name" file to store long file name (except in PlaintextNames mode)
-	if !fs.args.PlaintextNames && nametransform.IsLongContent(cName) {
-		err = fs.nameTransform.WriteLongNameAt(dirfd, cName, path)
-		if err != nil {
-			return fuse.ToStatus(err)
-		}
-		// Create "gocryptfs.longfile." device node
-		err = syscallcompat.MknodatUser(dirfd, cName, mode, int(dev), context)
-		if err != nil {
-			nametransform.DeleteLongNameAt(dirfd, cName)
-		}
-	} else {
-		// Create regular device node
-		err = syscallcompat.MknodatUser(dirfd, cName, mode, int(dev), context)
-	}
-	return fuse.ToStatus(err)
-}
-
-// Truncate - FUSE call. Truncates a file.
-//
-// Support truncate(2) by opening the file and calling ftruncate(2)
-// While the glibc "truncate" wrapper seems to always use ftruncate, fsstress from
-// xfstests uses this a lot by calling "truncate64" directly.
-//
-// Symlink-safe by letting file.Truncate() do all the work.
-func (fs *FS) Truncate(path string, offset uint64, context *fuse.Context) (code fuse.Status) {
-	file, code := fs.Open(path, uint32(os.O_RDWR), context)
-	if code != fuse.OK {
-		return code
-	}
-	code = file.Truncate(offset)
-	file.Release()
-	return code
-}
-
-// Utimens - FUSE call. Set the timestamps on file "path".
-//
-// Symlink-safe through UtimesNanoAt.
-func (fs *FS) Utimens(path string, a *time.Time, m *time.Time, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	dirfd, cName, err := fs.openBackingDir(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	defer syscall.Close(dirfd)
-	err = syscallcompat.UtimesNanoAtNofollow(dirfd, cName, a, m)
-	return fuse.ToStatus(err)
-}
-
-// StatFs - FUSE call. Returns information about the filesystem.
-//
-// Symlink-safe because the passed path is ignored.
-func (fs *FS) StatFs(path string) *fuse.StatfsOut {
-	var st syscall.Statfs_t
-	err := syscall.Statfs(fs.args.Cipherdir, &st)
-	if err == nil {
-		var out fuse.StatfsOut
-		out.FromStatfsT(&st)
-		return &out
-	}
-	return nil
-}
-
-// decryptSymlinkTarget: "cData64" is base64-decoded and decrypted
-// like file contents (GCM).
-// The empty string decrypts to the empty string.
-//
-// This function does not do any I/O and is hence symlink-safe.
-func (fs *FS) decryptSymlinkTarget(cData64 string) (string, error) {
-	if cData64 == "" {
-		return "", nil
-	}
-	cData, err := fs.nameTransform.B64DecodeString(cData64)
-	if err != nil {
-		return "", err
-	}
-	data, err := fs.contentEnc.DecryptBlock([]byte(cData), 0, nil)
-	if err != nil {
-		return "", err
-	}
-	return string(data), nil
-}
-
-// Readlink - FUSE call.
-//
-// Symlink-safe through openBackingDir() + Readlinkat().
-func (fs *FS) Readlink(relPath string, context *fuse.Context) (out string, status fuse.Status) {
-	dirfd, cName, err := fs.openBackingDir(relPath)
-	if err != nil {
-		return "", fuse.ToStatus(err)
-	}
-	defer syscall.Close(dirfd)
-	cTarget, err := syscallcompat.Readlinkat(dirfd, cName)
-	if err != nil {
-		return "", fuse.ToStatus(err)
-	}
-	if fs.args.PlaintextNames {
-		return cTarget, fuse.OK
-	}
-	// Symlinks are encrypted like file contents (GCM) and base64-encoded
-	target, err := fs.decryptSymlinkTarget(cTarget)
-	if err != nil {
-		tlog.Warn.Printf("Readlink %q: decrypting target failed: %v", cName, err)
-		return "", fuse.EIO
-	}
-	return string(target), fuse.OK
-}
-
-// Unlink - FUSE call. Delete a file.
-//
-// Symlink-safe through use of Unlinkat().
-func (fs *FS) Unlink(path string, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	dirfd, cName, err := fs.openBackingDir(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	defer syscall.Close(dirfd)
-	// Delete content
-	err = syscallcompat.Unlinkat(dirfd, cName, 0)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	// Delete ".name" file
-	if !fs.args.PlaintextNames && nametransform.IsLongContent(cName) {
-		err = nametransform.DeleteLongNameAt(dirfd, cName)
-		if err != nil {
-			tlog.Warn.Printf("Unlink: could not delete .name file: %v", err)
-		}
-	}
-	return fuse.ToStatus(err)
-}
-
-// encryptSymlinkTarget: "data" is encrypted like file contents (GCM)
-// and base64-encoded.
-// The empty string encrypts to the empty string.
-//
-// Symlink-safe because it does not do any I/O.
-func (fs *FS) encryptSymlinkTarget(data string) (cData64 string) {
-	if data == "" {
-		return ""
-	}
-	cData := fs.contentEnc.EncryptBlock([]byte(data), 0, nil)
-	cData64 = fs.nameTransform.B64EncodeToString(cData)
-	return cData64
-}
-
-// Symlink - FUSE call. Create a symlink.
-//
-// Symlink-safe through use of Symlinkat.
-func (fs *FS) Symlink(target string, linkName string, context *fuse.Context) (code fuse.Status) {
-	tlog.Debug.Printf("Symlink(\"%s\", \"%s\")", target, linkName)
-	if fs.isFiltered(linkName) {
-		return fuse.EPERM
-	}
-	dirfd, cName, err := fs.openBackingDir(linkName)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	defer syscall.Close(dirfd)
-	// Make sure context is nil if we don't want to preserve the owner
-	if !fs.args.PreserveOwner {
-		context = nil
-	}
-	cTarget := target
-	if !fs.args.PlaintextNames {
-		// Symlinks are encrypted like file contents (GCM) and base64-encoded
-		cTarget = fs.encryptSymlinkTarget(target)
-	}
-	// Create ".name" file to store long file name (except in PlaintextNames mode)
-	if !fs.args.PlaintextNames && nametransform.IsLongContent(cName) {
-		err = fs.nameTransform.WriteLongNameAt(dirfd, cName, linkName)
-		if err != nil {
-			return fuse.ToStatus(err)
-		}
-		// Create "gocryptfs.longfile." symlink
-		err = syscallcompat.SymlinkatUser(cTarget, dirfd, cName, context)
-		if err != nil {
-			nametransform.DeleteLongNameAt(dirfd, cName)
-		}
-	} else {
-		// Create symlink
-		err = syscallcompat.SymlinkatUser(cTarget, dirfd, cName, context)
-	}
-	return fuse.ToStatus(err)
-}
-
-// Rename - FUSE call.
-//
-// Symlink-safe through Renameat().
-func (fs *FS) Rename(oldPath string, newPath string, context *fuse.Context) (code fuse.Status) {
-	defer fs.dirCache.Clear()
-	if fs.isFiltered(newPath) {
-		return fuse.EPERM
-	}
-	oldDirfd, oldCName, err := fs.openBackingDir(oldPath)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	defer syscall.Close(oldDirfd)
-	newDirfd, newCName, err := fs.openBackingDir(newPath)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	defer syscall.Close(newDirfd)
-	// Easy case.
-	if fs.args.PlaintextNames {
-		return fuse.ToStatus(syscallcompat.Renameat(oldDirfd, oldCName, newDirfd, newCName))
-	}
-	// Long destination file name: create .name file
-	nameFileAlreadyThere := false
-	if nametransform.IsLongContent(newCName) {
-		err = fs.nameTransform.WriteLongNameAt(newDirfd, newCName, newPath)
-		// Failure to write the .name file is expected when the target path already
-		// exists. Since hashes are pretty unique, there is no need to modify the
-		// .name file in this case, and we ignore the error.
-		if err == syscall.EEXIST {
-			nameFileAlreadyThere = true
-		} else if err != nil {
-			return fuse.ToStatus(err)
-		}
-	}
-	// Actual rename
-	tlog.Debug.Printf("Renameat %d/%s -> %d/%s\n", oldDirfd, oldCName, newDirfd, newCName)
-	err = syscallcompat.Renameat(oldDirfd, oldCName, newDirfd, newCName)
-	if err == syscall.ENOTEMPTY || err == syscall.EEXIST {
-		// If an empty directory is overwritten we will always get an error as
-		// the "empty" directory will still contain gocryptfs.diriv.
-		// Interestingly, ext4 returns ENOTEMPTY while xfs returns EEXIST.
-		// We handle that by trying to fs.Rmdir() the target directory and trying
-		// again.
-		tlog.Debug.Printf("Rename: Handling ENOTEMPTY")
-		if fs.Rmdir(newPath, context) == fuse.OK {
-			err = syscallcompat.Renameat(oldDirfd, oldCName, newDirfd, newCName)
-		}
-	}
-	if err != nil {
-		if nametransform.IsLongContent(newCName) && nameFileAlreadyThere == false {
-			// Roll back .name creation unless the .name file was already there
-			nametransform.DeleteLongNameAt(newDirfd, newCName)
-		}
-		return fuse.ToStatus(err)
-	}
-	if nametransform.IsLongContent(oldCName) {
-		nametransform.DeleteLongNameAt(oldDirfd, oldCName)
-	}
-	return fuse.OK
-}
-
-// Link - FUSE call. Creates a hard link at "newPath" pointing to file
-// "oldPath".
-//
-// Symlink-safe through use of Linkat().
-func (fs *FS) Link(oldPath string, newPath string, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(newPath) {
-		return fuse.EPERM
-	}
-	oldDirFd, cOldName, err := fs.openBackingDir(oldPath)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	defer syscall.Close(oldDirFd)
-	newDirFd, cNewName, err := fs.openBackingDir(newPath)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	defer syscall.Close(newDirFd)
-	// Handle long file name (except in PlaintextNames mode)
-	if !fs.args.PlaintextNames && nametransform.IsLongContent(cNewName) {
-		err = fs.nameTransform.WriteLongNameAt(newDirFd, cNewName, newPath)
-		if err != nil {
-			return fuse.ToStatus(err)
-		}
-		// Create "gocryptfs.longfile." link
-		err = syscallcompat.Linkat(oldDirFd, cOldName, newDirFd, cNewName, 0)
-		if err != nil {
-			nametransform.DeleteLongNameAt(newDirFd, cNewName)
-		}
-	} else {
-		// Create regular link
-		err = syscallcompat.Linkat(oldDirFd, cOldName, newDirFd, cNewName, 0)
-	}
-	return fuse.ToStatus(err)
-}
-
-// Access - FUSE call. Check if a file can be accessed in the specified mode(s)
-// (read, write, execute).
-//
-// From https://github.com/libfuse/libfuse/blob/master/include/fuse.h :
-//
-// > Check file access permissions
-// >
-// > If the 'default_permissions' mount option is given, this method is not
-// > called.
-//
-// We always enable default_permissions when -allow_other is passed, so there
-// is no need for this function to check the uid in fuse.Context.
-//
-// Symlink-safe through use of faccessat.
-func (fs *FS) Access(relPath string, mode uint32, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(relPath) {
-		return fuse.EPERM
-	}
-	dirfd, cName, err := fs.openBackingDir(relPath)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	err = syscallcompat.Faccessat(dirfd, cName, mode)
-	syscall.Close(dirfd)
-	return fuse.ToStatus(err)
-}
-
-// reportMitigatedCorruption is used to report a corruption that was transparently
-// mitigated and did not return an error to the user. Pass the name of the corrupt
-// item (filename for OpenDir(), xattr name for ListXAttr() etc).
-// See the MitigatedCorruptions channel for more info.
-func (fs *FS) reportMitigatedCorruption(item string) {
-	if fs.MitigatedCorruptions == nil {
-		return
-	}
-	select {
-	case fs.MitigatedCorruptions <- item:
-	case <-time.After(1 * time.Second):
-		tlog.Warn.Printf("BUG: reportCorruptItem: timeout")
-		//debug.PrintStack()
-		return
-	}
-}
-
-// isFiltered - check if plaintext "path" should be forbidden
-//
-// Prevents name clashes with internal files when file names are not encrypted
-func (fs *FS) isFiltered(path string) bool {
-	atomic.StoreUint32(&fs.IsIdle, 0)
-
-	if !fs.args.PlaintextNames {
-		return false
-	}
-	// gocryptfs.conf in the root directory is forbidden
-	if path == configfile.ConfDefaultName {
-		tlog.Info.Printf("The name /%s is reserved when -plaintextnames is used\n",
-			configfile.ConfDefaultName)
-		return true
-	}
-	// Note: gocryptfs.diriv is NOT forbidden because diriv and plaintextnames
-	// are exclusive
-	return false
-}