1 files changed, 87 insertions, 0 deletions

diff --git a/drivers/s390/cio/airq.c b/drivers/s390/cio/airq.c
new file mode 100644
index 000000000000..3720e77b465f
--- /dev/null
+++ b/drivers/s390/cio/airq.c
@@ -0,0 +1,87 @@
+/*
+ *  drivers/s390/cio/airq.c
+ *   S/390 common I/O routines -- support for adapter interruptions
+ *
+ *   $Revision: 1.12 $
+ *
+ *    Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
+ *                            IBM Corporation
+ *    Author(s): Ingo Adlung (adlung@de.ibm.com)
+ *               Cornelia Huck (cohuck@de.ibm.com)
+ *               Arnd Bergmann (arndb@de.ibm.com)
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/rcupdate.h>
+
+#include "cio_debug.h"
+#include "airq.h"
+
+static adapter_int_handler_t adapter_handler;
+
+/*
+ * register for adapter interrupts
+ *
+ * With HiperSockets the zSeries architecture provides for
+ *  means of adapter interrups, pseudo I/O interrupts that are
+ *  not tied to an I/O subchannel, but to an adapter. However,
+ *  it doesn't disclose the info how to enable/disable them, but
+ *  to recognize them only. Perhaps we should consider them
+ *  being shared interrupts, and thus build a linked list
+ *  of adapter handlers ... to be evaluated ...
+ */
+int
+s390_register_adapter_interrupt (adapter_int_handler_t handler)
+{
+        int ret;
+        char dbf_txt[15];
+
+        CIO_TRACE_EVENT (4, "rgaint");
+
+        if (handler == NULL)
+                ret = -EINVAL;
+        else
+                ret = (cmpxchg(&adapter_handler, NULL, handler) ? -EBUSY : 0);
+        if (!ret)
+                synchronize_kernel();
+
+        sprintf (dbf_txt, "ret:%d", ret);
+        CIO_TRACE_EVENT (4, dbf_txt);
+
+        return ret;
+}
+
+int
+s390_unregister_adapter_interrupt (adapter_int_handler_t handler)
+{
+        int ret;
+        char dbf_txt[15];
+
+        CIO_TRACE_EVENT (4, "urgaint");
+
+        if (handler == NULL)
+                ret = -EINVAL;
+        else {
+                adapter_handler = NULL;
+                synchronize_kernel();
+                ret = 0;
+        }
+        sprintf (dbf_txt, "ret:%d", ret);
+        CIO_TRACE_EVENT (4, dbf_txt);
+
+        return ret;
+}
+
+void
+do_adapter_IO (void)
+{
+        CIO_TRACE_EVENT (6, "doaio");
+
+        if (adapter_handler)
+                (*adapter_handler) ();
+}
+
+EXPORT_SYMBOL (s390_register_adapter_interrupt);
+EXPORT_SYMBOL (s390_unregister_adapter_interrupt);