[IrDA]: Calling ppp_unregister_channel() from process context

We need to call ppp_unregister_channel() when IrNET disconnects, and this
must be done from a process context.

Bug reported and patch tested by Guennadi Liakhovetski.

Signed-off-by: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 26 insertions, 10 deletions

diff --git a/net/irda/irnet/irnet.h b/net/irda/irnet/irnet.h
index 873ae189e37a..bc2e15ce7004 100644
--- a/net/irda/irnet/irnet.h
+++ b/net/irda/irnet/irnet.h
@@ -419,7 +419,7 @@ typedef struct irnet_socket
   u32                   raccm;          /* to please pppd - dummy) */
   unsigned int          flags;          /* PPP flags (compression, ...) */
   unsigned int          rbits;          /* Unused receive flags ??? */
-
+  struct work_struct disconnect_work;   /* Process context disconnection */
   /* ------------------------ IrTTP part ------------------------ */
   /* We create a pseudo "socket" over the IrDA tranport */
   unsigned long         ttp_open;       /* Set when IrTTP is ready */
diff --git a/net/irda/irnet/irnet_irda.c b/net/irda/irnet/irnet_irda.c
index c378e668af0c..a4f1439ffdd8 100644
--- a/net/irda/irnet/irnet_irda.c
+++ b/net/irda/irnet/irnet_irda.c
@@ -10,6 +10,27 @@
 
 #include "irnet_irda.h"         /* Private header */
 
+/*
+ * PPP disconnect work: we need to make sure we're in
+ * process context when calling ppp_unregister_channel().
+ */
+static void irnet_ppp_disconnect(struct work_struct *work)
+{
+        irnet_socket * self =
+                container_of(work, irnet_socket, disconnect_work);
+
+        if (self == NULL)
+                return;
+        /*
+         * If we were connected, cleanup & close the PPP
+         * channel, which will kill pppd (hangup) and the rest.
+         */
+        if (self->ppp_open && !self->ttp_open && !self->ttp_connect) {
+                ppp_unregister_channel(&self->chan);
+                self->ppp_open = 0;
+        }
+}
+
 /************************* CONTROL CHANNEL *************************/
 /*
  * When ppp is not active, /dev/irnet act as a control channel.
@@ -499,6 +520,8 @@ irda_irnet_create(irnet_socket *	self)
 #endif /* DISCOVERY_NOMASK */
   self->tx_flow = FLOW_START;   /* Flow control from IrTTP */
 
+  INIT_WORK(&self->disconnect_work, irnet_ppp_disconnect);
+
   DEXIT(IRDA_SOCK_TRACE, "\n");
   return(0);
 }
@@ -1134,15 +1157,8 @@ irnet_disconnect_indication(void *	instance,
     {
       if(test_open)
         {
-#ifdef MISSING_PPP_API
-          /* ppp_unregister_channel() wants a user context, which we
-           * are guaranteed to NOT have here. What are we supposed
-           * to do here ? Jean II */
-          /* If we were connected, cleanup & close the PPP channel,
-           * which will kill pppd (hangup) and the rest */
-          ppp_unregister_channel(&self->chan);
-          self->ppp_open = 0;
-#endif
+          /* ppp_unregister_channel() wants a user context. */
+          schedule_work(&self->disconnect_work);
         }
       else
         {