X-Git-Url: http://git.onelab.eu/?p=linux-2.6.git;a=blobdiff_plain;f=drivers%2Fs390%2Fcio%2Fairq.c;h=3720e77b465fcf463e1ed5f178226cf29457e118;hp=71c03c87e5e295b0fe1bd0852dee2e68eab7b954;hb=9213980e6a70d8473e0ffd4b39ab5b6caaba9ff5;hpb=c449269f45c2cdf53af08c8d0af37472f66539d9

diff --git a/drivers/s390/cio/airq.c b/drivers/s390/cio/airq.c
index 71c03c87e..3720e77b4 100644
--- a/drivers/s390/cio/airq.c
+++ b/drivers/s390/cio/airq.c
@@ -2,7 +2,7 @@
  *  drivers/s390/cio/airq.c
  *   S/390 common I/O routines -- support for adapter interruptions
  *
- *   $Revision: 1.11 $
+ *   $Revision: 1.12 $
  *
  *    Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
  *			      IBM Corporation
@@ -14,11 +14,11 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/rcupdate.h>
 
 #include "cio_debug.h"
 #include "airq.h"
 
-static spinlock_t adapter_lock = SPIN_LOCK_UNLOCKED;
 static adapter_int_handler_t adapter_handler;
 
 /*
@@ -40,23 +40,17 @@ s390_register_adapter_interrupt (adapter_int_handler_t handler)
 
 	CIO_TRACE_EVENT (4, "rgaint");
 
-	spin_lock (&adapter_lock);
-
 	if (handler == NULL)
 		ret = -EINVAL;
-	else if (adapter_handler)
-		ret = -EBUSY;
-	else {
-		adapter_handler = handler;
-		ret = 0;
-	}
-
-	spin_unlock (&adapter_lock);
+	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);
+	return ret;
 }
 
 int
@@ -67,38 +61,26 @@ s390_unregister_adapter_interrupt (adapter_int_handler_t handler)
 
 	CIO_TRACE_EVENT (4, "urgaint");
 
-	spin_lock (&adapter_lock);
-
 	if (handler == NULL)
 		ret = -EINVAL;
-	else if (handler != adapter_handler)
-		ret = -EINVAL;
 	else {
 		adapter_handler = NULL;
+		synchronize_kernel();
 		ret = 0;
 	}
-
-	spin_unlock (&adapter_lock);
-
 	sprintf (dbf_txt, "ret:%d", ret);
 	CIO_TRACE_EVENT (4, dbf_txt);
 
-	return (ret);
+	return ret;
 }
 
 void
 do_adapter_IO (void)
 {
-	CIO_TRACE_EVENT (4, "doaio");
-
-	spin_lock (&adapter_lock);
+	CIO_TRACE_EVENT (6, "doaio");
 
 	if (adapter_handler)
 		(*adapter_handler) ();
-
-	spin_unlock (&adapter_lock);
-
-	return;
 }
 
 EXPORT_SYMBOL (s390_register_adapter_interrupt);