Skip to content

Commit

Permalink
v2api: File2: implement Release, Read, Write, Fsync, Flush, Allocate
Browse files Browse the repository at this point in the history 
Fortunately, this just means fixing up the function
signatures.
  • Loading branch information
@rfjakob
rfjakob committed Jul 12, 2020
1 parent d539a4c commit 6196a5b
Show file tree
Hide file tree
Showing 5 changed files with 89 additions and 87 deletions.
78 changes: 40 additions & 38 deletions internal/fusefrontend/file2.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -25,6 +25,7 @@ import (
"github.com/rfjakob/gocryptfs/internal/tlog"
)

// File2 implements the go-fuse v2 API (github.com/hanwen/go-fuse/v2/fs)
type File2 struct {
fd *os.File
// Has Release() already been called on this file? This also means that the
Expand Down Expand Up @@ -129,7 +130,7 @@ func (f *File2) createHeader() (fileID []byte, err error) {
//
// Called by Read() for normal reading,
// by Write() and Truncate() via doWrite() for Read-Modify-Write.
func (f *File2) doRead(dst []byte, off uint64, length uint64) ([]byte, fuse.Status) {
func (f *File2) doRead(dst []byte, off uint64, length uint64) ([]byte, syscall.Errno) {
// Get the file ID, either from the open file table, or from disk.
var fileID []byte
f.fileTableEntry.IDLock.Lock()
Expand All @@ -144,15 +145,15 @@ func (f *File2) doRead(dst []byte, off uint64, length uint64) ([]byte, fuse.Stat
f.fileTableEntry.IDLock.Unlock()
if err == io.EOF {
// Empty file
return nil, fuse.OK
return nil, 0
}
buf := make([]byte, 100)
n, _ := f.fd.ReadAt(buf, 0)
buf = buf[:n]
hexdump := hex.EncodeToString(buf)
tlog.Warn.Printf("doRead %d: corrupt header: %v\nFile hexdump (%d bytes): %s",
f.qIno.Ino, err, n, hexdump)
return nil, fuse.EIO
return nil, syscall.EIO
}
// Save into the file table
f.fileTableEntry.ID = fileID
Expand All @@ -173,12 +174,12 @@ func (f *File2) doRead(dst []byte, off uint64, length uint64) ([]byte, fuse.Stat
n, err := f.fd.ReadAt(ciphertext, int64(alignedOffset))
if err != nil && err != io.EOF {
tlog.Warn.Printf("read: ReadAt: %s", err.Error())
return nil, fuse.ToStatus(err)
return nil, fs.ToErrno(err)
}
// The ReadAt came back empty. We can skip all the decryption and return early.
if n == 0 {
f.rootNode.contentEnc.CReqPool.Put(ciphertext)
return dst, fuse.OK
return dst, 0
}
// Truncate ciphertext buffer down to actually read bytes
ciphertext = ciphertext[0:n]
Expand All @@ -198,7 +199,7 @@ func (f *File2) doRead(dst []byte, off uint64, length uint64) ([]byte, fuse.Stat
} else {
curruptBlockNo := firstBlockNo + f.contentEnc.PlainOffToBlockNo(uint64(len(plaintext)))
tlog.Warn.Printf("doRead %d: corrupt block #%d: %v", f.qIno.Ino, curruptBlockNo, err)
return nil, fuse.EIO
return nil, syscall.EIO
}
}

Expand All @@ -216,15 +217,15 @@ func (f *File2) doRead(dst []byte, off uint64, length uint64) ([]byte, fuse.Stat
out = append(dst, out...)
f.rootNode.contentEnc.PReqPool.Put(plaintext)

return out, fuse.OK
return out, 0
}

// Read - FUSE call
func (f *File2) Read(buf []byte, off int64) (resultData fuse.ReadResult, code fuse.Status) {
func (f *File2) Read(ctx context.Context, buf []byte, off int64) (resultData fuse.ReadResult, errno syscall.Errno) {
if len(buf) > fuse.MAX_KERNEL_WRITE {
// This would crash us due to our fixed-size buffer pool
tlog.Warn.Printf("Read: rejecting oversized request with EMSGSIZE, len=%d", len(buf))
return nil, fuse.Status(syscall.EMSGSIZE)
return nil, syscall.EMSGSIZE
}
f.fdLock.RLock()
defer f.fdLock.RUnlock()
Expand All @@ -236,15 +237,15 @@ func (f *File2) Read(buf []byte, off int64) (resultData fuse.ReadResult, code fu
if f.rootNode.args.SerializeReads {
serialize_reads.Wait(off, len(buf))
}
out, status := f.doRead(buf[:0], uint64(off), uint64(len(buf)))
out, errno := f.doRead(buf[:0], uint64(off), uint64(len(buf)))
if f.rootNode.args.SerializeReads {
serialize_reads.Done()
}
if status != fuse.OK {
return nil, status
if errno != 0 {
return nil, errno
}
tlog.Debug.Printf("ino%d: Read: status %v, returning %d bytes", f.qIno.Ino, status, len(out))
return fuse.ReadResultData(out), status
tlog.Debug.Printf("ino%d: Read: errno=%d, returning %d bytes", f.qIno.Ino, errno, len(out))
return fuse.ReadResultData(out), errno
}

// doWrite - encrypt "data" and write it to plaintext offset "off"
Expand All @@ -256,7 +257,7 @@ func (f *File2) Read(buf []byte, off int64) (resultData fuse.ReadResult, code fu
// and by Truncate() to rewrite the last file block.
//
// Empty writes do nothing and are allowed.
func (f *File2) doWrite(data []byte, off int64) (uint32, fuse.Status) {
func (f *File2) doWrite(data []byte, off int64) (uint32, syscall.Errno) {
fileWasEmpty := false
// Get the file ID, create a new one if it does not exist yet.
var fileID []byte
Expand All @@ -274,7 +275,7 @@ func (f *File2) doWrite(data []byte, off int64) (uint32, fuse.Status) {
fileWasEmpty = true
}
if err != nil {
return 0, fuse.ToStatus(err)
return 0, fs.ToErrno(err)
}
f.fileTableEntry.ID = fileID
}
Expand All @@ -287,10 +288,10 @@ func (f *File2) doWrite(data []byte, off int64) (uint32, fuse.Status) {
// Incomplete block -> Read-Modify-Write
if b.IsPartial() {
// Read
oldData, status := f.doRead(nil, b.BlockPlainOff(), f.contentEnc.PlainBS())
if status != fuse.OK {
tlog.Warn.Printf("ino%d fh%d: RMW read failed: %s", f.qIno.Ino, f.intFd(), status.String())
return 0, status
oldData, errno := f.doRead(nil, b.BlockPlainOff(), f.contentEnc.PlainBS())
if errno != 0 {
tlog.Warn.Printf("ino%d fh%d: RMW read failed: errno=%d", f.qIno.Ino, f.intFd(), errno)
return 0, errno
}
// Modify
blockData = f.contentEnc.MergeBlocks(oldData, blockData, int(b.Skip))
Expand Down Expand Up @@ -321,7 +322,7 @@ func (f *File2) doWrite(data []byte, off int64) (uint32, fuse.Status) {
tlog.Warn.Printf("ino%d fh%d: doWrite: rollback failed: %v", f.qIno.Ino, f.intFd(), err2)
}
}
return 0, fuse.ToStatus(err)
return 0, fs.ToErrno(err)
}
}
// Write
Expand All @@ -331,9 +332,9 @@ func (f *File2) doWrite(data []byte, off int64) (uint32, fuse.Status) {
if err != nil {
tlog.Warn.Printf("ino%d fh%d: doWrite: WriteAt off=%d len=%d failed: %v",
f.qIno.Ino, f.intFd(), cOff, len(ciphertext), err)
return 0, fuse.ToStatus(err)
return 0, fs.ToErrno(err)
}
return uint32(len(data)), fuse.OK
return uint32(len(data)), 0
}

// isConsecutiveWrite returns true if the current write
Expand All @@ -349,18 +350,18 @@ func (f *File2) isConsecutiveWrite(off int64) bool {
// Write - FUSE call
//
// If the write creates a hole, pads the file to the next block boundary.
func (f *File2) Write(data []byte, off int64) (uint32, fuse.Status) {
func (f *File2) Write(ctx context.Context, data []byte, off int64) (uint32, syscall.Errno) {
if len(data) > fuse.MAX_KERNEL_WRITE {
// This would crash us due to our fixed-size buffer pool
tlog.Warn.Printf("Write: rejecting oversized request with EMSGSIZE, len=%d", len(data))
return 0, fuse.Status(syscall.EMSGSIZE)
return 0, syscall.EMSGSIZE
}
f.fdLock.RLock()
defer f.fdLock.RUnlock()
if f.released {
// The file descriptor has been closed concurrently
tlog.Warn.Printf("ino%d fh%d: Write on released file", f.qIno.Ino, f.intFd())
return 0, fuse.EBADF
return 0, syscall.EBADF
}
f.fileTableEntry.ContentLock.Lock()
defer f.fileTableEntry.ContentLock.Unlock()
Expand All @@ -369,21 +370,21 @@ func (f *File2) Write(data []byte, off int64) (uint32, fuse.Status) {
// But if the write directly follows an earlier write, it cannot create a
// hole, and we can save one Stat() call.
if !f.isConsecutiveWrite(off) {
status := f.writePadHole(off)
if !status.Ok() {
return 0, status
errno := f.writePadHole(off)
if errno != 0 {
return 0, errno
}
}
n, status := f.doWrite(data, off)
if status.Ok() {
n, errno := f.doWrite(data, off)
if errno != 0 {
f.lastOpCount = openfiletable.WriteOpCount()
f.lastWrittenOffset = off + int64(len(data)) - 1
}
return n, status
return n, errno
}

// Release - FUSE call, close file
func (f *File2) Release() {
func (f *File2) Release(ctx context.Context) syscall.Errno {
f.fdLock.Lock()
if f.released {
log.Panicf("ino%d fh%d: double release", f.qIno.Ino, f.intFd())
Expand All @@ -392,10 +393,11 @@ func (f *File2) Release() {
openfiletable.Unregister(f.qIno)
f.fd.Close()
f.fdLock.Unlock()
return 0
}

// Flush - FUSE call
func (f *File2) Flush() fuse.Status {
func (f *File2) Flush(ctx context.Context) syscall.Errno {
f.fdLock.RLock()
defer f.fdLock.RUnlock()

Expand All @@ -405,18 +407,18 @@ func (f *File2) Flush() fuse.Status {
newFd, err := syscall.Dup(f.intFd())

if err != nil {
return fuse.ToStatus(err)
return fs.ToErrno(err)
}
err = syscall.Close(newFd)
return fuse.ToStatus(err)
return fs.ToErrno(err)
}

// Fsync FUSE call
func (f *File2) Fsync(flags int) (code fuse.Status) {
func (f *File2) Fsync(ctx context.Context, flags uint32) (errno syscall.Errno) {
f.fdLock.RLock()
defer f.fdLock.RUnlock()

return fuse.ToStatus(syscall.Fsync(f.intFd()))
return fs.ToErrno(syscall.Fsync(f.intFd()))
}

// Getattr FUSE call (like stat)
Expand Down
Loading

0 comments on commit 6196a5b

Please sign in to comment.