tty/n_gsm: avoid fifo overflow in gsm_dlci_data_output

[pandora-kernel.git] / drivers / tty / n_gsm.c

diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 14c26cd..4cb0d0a 100644 (file)
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -809,37 +809,41 @@ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci)
 {
        struct gsm_msg *msg;
        u8 *dp;
-       int len, size;
+       int len, total_size, size;
        int h = dlci->adaption - 1;
 
-       len = kfifo_len(dlci->fifo);
-       if (len == 0)
-               return 0;
-
-       /* MTU/MRU count only the data bits */
-       if (len > gsm->mtu)
-               len = gsm->mtu;
-
-       size = len + h;
-
-       msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype);
-       /* FIXME: need a timer or something to kick this so it can't
-          get stuck with no work outstanding and no buffer free */
-       if (msg == NULL)
-               return -ENOMEM;
-       dp = msg->data;
-       switch (dlci->adaption) {
-       case 1: /* Unstructured */
-               break;
-       case 2: /* Unstructed with modem bits. Always one byte as we never
-                  send inline break data */
-               *dp++ = gsm_encode_modem(dlci);
-               break;
+       total_size = 0;
+       while(1) {
+               len = kfifo_len(dlci->fifo);
+               if (len == 0)
+                       return total_size;
+
+               /* MTU/MRU count only the data bits */
+               if (len > gsm->mtu)
+                       len = gsm->mtu;
+
+               size = len + h;
+
+               msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype);
+               /* FIXME: need a timer or something to kick this so it can't
+                  get stuck with no work outstanding and no buffer free */
+               if (msg == NULL)
+                       return -ENOMEM;
+               dp = msg->data;
+               switch (dlci->adaption) {
+               case 1: /* Unstructured */
+                       break;
+               case 2: /* Unstructed with modem bits. Always one byte as we never
+                          send inline break data */
+                       *dp++ = gsm_encode_modem(dlci);
+                       break;
+               }
+               WARN_ON(kfifo_out_locked(dlci->fifo, dp , len, &dlci->lock) != len);
+               __gsm_data_queue(dlci, msg);
+               total_size += size;
        }
-       WARN_ON(kfifo_out_locked(dlci->fifo, dp , len, &dlci->lock) != len);
-       __gsm_data_queue(dlci, msg);
        /* Bytes of data we used up */
-       return size;
+       return total_size;
 }
 
 /**