RX: Add rx_InterruptCall

Add rx_InterruptCall, to cause a call to error out and wakeup anyone
waiting to write or read to that call.

Reviewed-on: http://gerrit.openafs.org/2982
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>
Reviewed-by: Tom Keiser <tkeiser@sinenomine.net>
Tested-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 9fa496d11f)

Change-Id: I2e0f5eb2942830523b19d2596c50d0fba0fc9a1a
Reviewed-on: http://gerrit.openafs.org/3248
Tested-by: Derrick Brashear <shadow@dementia.org>
Reviewed-by: Derrick Brashear <shadow@dementia.org>

src/libafsrpc/afsrpc.def

@@ -266,7 +266,7 @@ EXPORTS
 ;       rx_FreeStatistics                       @271
 	rx_SetConnHardDeadTime			@272
 	rx_SetConnIdleDeadTime			@273
-;	rx_InterruptCall                        @274
+	rx_InterruptCall                        @274
         osi_Panic				@275
 
 ; lwp functions

src/rx/rx.c

@@ -4918,6 +4918,21 @@ rxi_ConnectionError(struct rx_connection *conn,
     }
 }
 
+/**
+ * Interrupt an in-progress call with the specified error and wakeup waiters.
+ *
+ * @param[in] call  The call to interrupt
+ * @param[in] error  The error code to send to the peer
+ */
+void
+rx_InterruptCall(struct rx_call *call, afs_int32 error)
+{
+    MUTEX_ENTER(&call->lock);
+    rxi_CallError(call, error);
+    rxi_SendCallAbort(call, NULL, 0, 1);
+    MUTEX_EXIT(&call->lock);
+}
+
 void
 rxi_CallError(struct rx_call *call, afs_int32 error)
 {

src/rx/rx_prototypes.h

@@ -81,6 +81,7 @@ extern void rx_SetArrivalProc(struct rx_call *call,
 						    int index),
 			      void * handle, int arg);
 extern afs_int32 rx_EndCall(struct rx_call *call, afs_int32 rc);
+extern void rx_InterruptCall(struct rx_call *call, afs_int32 error);
 extern void rx_Finalize(void);
 extern void rxi_PacketsUnWait(void);
 extern struct rx_service *rxi_FindService(osi_socket socket,

src/shlibafsrpc/libafsrpc.map

@@ -142,6 +142,7 @@
 	afs_xdr_short;
 	afs_xdr_string;
 	afs_xdr_vector;
+	rx_InterruptCall;
     local:
 	*;
 };