Don't fail in grow() if the pair is big enough.

fuse/mountstate.go

@@ -423,7 +423,7 @@ func (ms *MountState) TrySplice(header []byte, req *request, fdData *ReadResultF
 
 	_, err = pair.WriteTo(ms.mountFile.Fd(), total)
 	if err != nil {
-		return fmt.Errorf("splice write: %v", err)
+		return err
 	}
 	return nil
 }

splice/pair.go

@@ -17,15 +17,15 @@ func (p *Pair) MaxGrow() {
 }
 
 func (p *Pair) Grow(n int) bool {
+	if n <= p.size {
+		return true
+	}
 	if !resizable {
 		return false
 	}
 	if n > maxPipeSize {
 		return false
 	}
-	if n <= p.size {
-		return true
-	}
 
 	newsize, errNo := fcntl(p.r.Fd(), F_SETPIPE_SZ, n)
 	if errNo != 0 {
@@ -85,7 +85,7 @@ func (p *Pair) LoadFrom(fd uintptr, sz int) (int, error) {
 func (p *Pair) WriteTo(fd uintptr, n int) (int, error) {
 	m, err := syscall.Splice(int(p.r.Fd()), nil, int(fd), nil, int(n), 0)
 	if err != nil {
-		err = os.NewSyscallError("Splice write to: ", err)
+		err = os.NewSyscallError("Splice write", err)
 	}
 	return int(m), err
 }