patch-2.4.2 linux/arch/s390/kernel/s390_ext.c

• Lines: 78
• Date: Tue Feb 13 14:13:43 2001
• Orig file: v2.4.1/linux/arch/s390/kernel/s390_ext.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.1/linux/arch/s390/kernel/s390_ext.c linux/arch/s390/kernel/s390_ext.c
@@ -0,0 +1,77 @@
+/*
+ *  arch/s390/kernel/s390_ext.c
+ *
+ *  S390 version
+ *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Holger Smolinski (Holger.Smolinski@de.ibm.com),
+ *               Martin Schwidefsky (schwidefsky@de.ibm.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/malloc.h>
+#include <asm/lowcore.h>
+#include <asm/s390_ext.h>
+
+/*
+ * Simple hash strategy: index = code & 0xff;
+ * ext_int_hash[index] is the start of the list for all external interrupts
+ * that hash to this index. With the current set of external interrupts 
+ * (0x1202 external call, 0x1004 cpu timer, 0x2401 hwc console and 0x4000
+ * iucv) this is always the first element. 
+ */
+ext_int_info_t *ext_int_hash[256] = { 0, };
+ext_int_info_t ext_int_info_timer;
+ext_int_info_t ext_int_info_hwc;
+
+int register_external_interrupt(__u16 code, ext_int_handler_t handler) {
+        ext_int_info_t *p;
+        int index;
+
+        index = code & 0xff;
+        p = ext_int_hash[index];
+        while (p != NULL) {
+                if (p->code == code)
+                        return -EBUSY;
+                p = p->next;
+        }
+        if (code == 0x1004) /* time_init is done before kmalloc works :-/ */
+                p = &ext_int_info_timer;
+        else if (code == 0x2401) /* hwc_init is done too early too */
+                p = &ext_int_info_hwc;
+        else
+                p = (ext_int_info_t *)
+                          kmalloc(sizeof(ext_int_info_t), GFP_ATOMIC);
+        if (p == NULL)
+                return -ENOMEM;
+        p->code = code;
+        p->handler = handler;
+        p->next = ext_int_hash[index];
+        ext_int_hash[index] = p;
+        return 0;
+}
+
+int unregister_external_interrupt(__u16 code, ext_int_handler_t handler) {
+        ext_int_info_t *p, *q;
+        int index;
+
+        index = code & 0xff;
+        q = NULL;
+        p = ext_int_hash[index];
+        while (p != NULL) {
+                if (p->code == code && p->handler == handler)
+                        break;
+                q = p;
+                p = p->next;
+        }
+        if (p == NULL)
+                return -ENOENT;
+        if (q != NULL)
+                q->next = p->next;
+        else
+                ext_int_hash[index] = p->next;
+        if (code != 0x1004 && code != 0x2401)
+                kfree(p);
+        return 0;
+}
+
+