diff --git a/ttynvt.c b/ttynvt.c
index 6594b5f..5530e8b 100644
--- a/ttynvt.c
+++ b/ttynvt.c
@@ -559,6 +559,11 @@ static const char *_ioctl_name(int cmd)
     }
 }
 
+#define CHECK_BUF_IN(sz) \
+    if (in_bufsz < sz)  do { in_bufsz  = sz; goto retry_in;  } while(0)
+#define CHECK_BUF_OUT(sz) \
+    if (out_bufsz < sz) do { out_bufsz = sz; goto retry_out; } while(0)
+
 static void
 ttynvt_ioctl(fuse_req_t req, int cmd, void *arg,
              struct fuse_file_info *info, unsigned int flags,
@@ -581,12 +586,7 @@ ttynvt_ioctl(fuse_req_t req, int cmd, void *arg,
     case TCSETSF:
     case TCSETSW:
     case TCSETS:
-        if (!in_bufsz)
-        {
-            struct iovec    iov = { arg, sizeof(struct termios) };
-            fuse_reply_ioctl_retry(req, &iov, 1, NULL, 0);
-        }
-        else
+        CHECK_BUF_IN(sizeof(struct termios));
         {
             speed_t         speed;
             int             csize, par, sb;
@@ -650,45 +650,20 @@ ttynvt_ioctl(fuse_req_t req, int cmd, void *arg,
         }
         break;
     case TCGETS:
-        if (out_bufsz)
-        {
-            fuse_reply_ioctl(req, 0, &tio, sizeof(struct termio));
-        }
-        else
-        {
-            struct iovec    iov = { arg, sizeof(struct termio) };
-            fuse_reply_ioctl_retry(req, NULL, 0, &iov, 1);
-        }
+        CHECK_BUF_OUT(sizeof(struct termios));
+        fuse_reply_ioctl(req, 0, &tio, sizeof(struct termios));
         break;
-
     case TIOCINQ:              /* Get the number of bytes in the input
                                  * buffer */
-        if (out_bufsz)
-        {
-            size_t          rx_size = _read_avail(tty);
-
-            fuse_reply_ioctl(req, 0, &rx_size, sizeof(size_t));
-        }
-        else
-        {
-            struct iovec    iov = { arg, sizeof(size_t) };
-            fuse_reply_ioctl_retry(req, NULL, 0, &iov, 1);
-        }
-
+        CHECK_BUF_OUT(sizeof(int));
+        val = _read_avail(tty);
+        fuse_reply_ioctl(req, 0, &val, sizeof(int));
         break;
     case TIOCOUTQ:             /* Get the number of bytes in the output
                                  * buffer */
-        if (out_bufsz)
-        {
-            size_t          tx_size = _write_avail(tty);
-
-            fuse_reply_ioctl(req, 0, &tx_size, sizeof(size_t));
-        }
-        else
-        {
-            struct iovec    iov = { arg, sizeof(size_t) };
-            fuse_reply_ioctl_retry(req, NULL, 0, &iov, 1);
-        }
+        CHECK_BUF_OUT(sizeof(int));
+        val = _write_avail(tty);
+        fuse_reply_ioctl(req, 0, &val, sizeof(int));
         break;
     case TCFLSH:
         if (arg == TCIFLUSH)
@@ -711,7 +686,6 @@ ttynvt_ioctl(fuse_req_t req, int cmd, void *arg,
         pthread_mutex_lock(&tty->tty_lock);
         tty->blen = 0;
         pthread_mutex_unlock(&tty->tty_lock);
-
         fuse_reply_ioctl(req, 0, 0, 0);
         break;
     case TCOFLUSH:
@@ -725,27 +699,13 @@ ttynvt_ioctl(fuse_req_t req, int cmd, void *arg,
         fuse_reply_ioctl(req, 0, 0, 0);
         break;
     case TIOCMGET:
-        if (out_bufsz)
-        {
-            fuse_reply_ioctl(req, 0, &mcr, sizeof(unsigned int));
-        }
-        else
-        {
-            struct iovec    iov = { arg, sizeof(unsigned int) };
-            fuse_reply_ioctl_retry(req, NULL, 0, &iov, 1);
-        }
+        CHECK_BUF_OUT(sizeof(int));
+        fuse_reply_ioctl(req, 0, &mcr, sizeof(int));
         break;
     case TIOCMBIS:
-        if (!in_bufsz)
-        {
-            struct iovec    iov = { arg, sizeof(unsigned int) };
-            fuse_reply_ioctl_retry(req, &iov, 1, NULL, 0);
-        }
-        else
-        {
-            tiocm = *(unsigned int *)in_buf;
-            fuse_reply_ioctl(req, 0, 0, 0);
-        }
+        CHECK_BUF_IN(sizeof(int));
+        tiocm = *(unsigned int *)in_buf;
+        fuse_reply_ioctl(req, 0, 0, 0);
         if (tiocm & TIOCM_RTS)
         {
             mcr |= TIOCM_RTS;
@@ -758,16 +718,9 @@ ttynvt_ioctl(fuse_req_t req, int cmd, void *arg,
         }
         break;
     case TIOCMBIC:
-        if (!in_bufsz)
-        {
-            struct iovec    iov = { arg, sizeof(unsigned int) };
-            fuse_reply_ioctl_retry(req, &iov, 1, NULL, 0);
-        }
-        else
-        {
-            tiocm = *(unsigned int *)in_buf;
-            fuse_reply_ioctl(req, 0, 0, 0);
-        }
+        CHECK_BUF_IN(sizeof(int));
+        tiocm = *(unsigned int *)in_buf;
+        fuse_reply_ioctl(req, 0, 0, 0);
         if (tiocm & TIOCM_RTS)
         {
             mcr &= ~TIOCM_RTS;
@@ -780,45 +733,48 @@ ttynvt_ioctl(fuse_req_t req, int cmd, void *arg,
         }
         break;
     case TIOCMSET:
-        if (!in_bufsz)
-        {
-            struct iovec    iov = { arg, sizeof(unsigned int) };
-            fuse_reply_ioctl_retry(req, &iov, 1, NULL, 0);
-        }
-        else
-        {
-            tiocm = *(unsigned int *)in_buf;
-            fuse_reply_ioctl(req, 0, 0, 0);
+        CHECK_BUF_IN(sizeof(int));
+        tiocm = *(unsigned int *)in_buf;
+        fuse_reply_ioctl(req, 0, 0, 0);
 
-            DBG("CFG ioctl: DTR=%c RTS=%c\n",
-                tiocm & TIOCM_DTR ? '1' : '0', tiocm & TIOCM_RTS ? '1' : '0');
+        DBG("CFG ioctl: DTR=%c RTS=%c\n",
+            tiocm & TIOCM_DTR ? '1' : '0', tiocm & TIOCM_RTS ? '1' : '0');
 
-            mcr &= ~(TIOCM_RTS | TIOCM_DTR);
-            mcr |= tiocm & (TIOCM_RTS | TIOCM_DTR);
-            telnet_rfc2217_ctl(tty->tn, (tiocm & TIOCM_DTR) ?
-                               TNS_CTL_DTR_ON : TNS_CTL_DTR_OFF);
-            telnet_rfc2217_ctl(tty->tn, (tiocm & TIOCM_RTS) ?
-                               TNS_CTL_RTS_ON : TNS_CTL_RTS_OFF);
-        }
+        mcr &= ~(TIOCM_RTS | TIOCM_DTR);
+        mcr |= tiocm & (TIOCM_RTS | TIOCM_DTR);
+        telnet_rfc2217_ctl(tty->tn, (tiocm & TIOCM_DTR) ?
+                           TNS_CTL_DTR_ON : TNS_CTL_DTR_OFF);
+        telnet_rfc2217_ctl(tty->tn, (tiocm & TIOCM_RTS) ?
+                           TNS_CTL_RTS_ON : TNS_CTL_RTS_OFF);
         break;
     case TCSBRK:
         fuse_reply_ioctl(req, 0, 0, 0);
         break;
     case TIOCGWINSZ:
-        if (out_bufsz)
+        CHECK_BUF_OUT(sizeof(struct winsize));
         {
             struct winsize  ws = {.ws_row = 25,.ws_col = 80 };
             fuse_reply_ioctl(req, 0, &ws, sizeof(struct winsize));
         }
-        else
+        break;
+
+    default:
+        fuse_reply_err(req, ENOSYS);
+        break;
+
+      retry_in:
         {
-            struct iovec    iov = { arg, sizeof(struct winsize) };
+            struct iovec    iov = { arg, in_bufsz };
+            fuse_reply_ioctl_retry(req, &iov, 1, NULL, 0);
+        }
+        break;
+
+      retry_out:
+        {
+            struct iovec    iov = { arg, out_bufsz };
             fuse_reply_ioctl_retry(req, NULL, 0, &iov, 1);
         }
         break;
-    default:
-        fuse_reply_err(req, ENOSYS);
-        return;
     }
 }