patch-2.3.99-pre8 linux/arch/s390/mm/extable.c

• Lines: 64
• Date: Fri May 12 11:41:45 2000
• Orig file: v2.3.99-pre7/linux/arch/s390/mm/extable.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.99-pre7/linux/arch/s390/mm/extable.c linux/arch/s390/mm/extable.c
@@ -0,0 +1,63 @@
+/*
+ *  arch/s390/mm/extable.c
+ *
+ *  S390 version
+ *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Hartmut Penner (hp@de.ibm.com)
+ *
+ *  Derived from "arch/i386/mm/extable.c"
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <asm/uaccess.h>
+
+extern const struct exception_table_entry __start___ex_table[];
+extern const struct exception_table_entry __stop___ex_table[];
+
+static inline unsigned long
+search_one_table(const struct exception_table_entry *first,
+		 const struct exception_table_entry *last,
+		 unsigned long value)
+{
+        while (first <= last) {
+		const struct exception_table_entry *mid;
+		long diff;
+
+		mid = (last - first) / 2 + first;
+		diff = mid->insn - value;
+                if (diff == 0)
+                        return mid->fixup;
+                else if (diff < 0)
+                        first = mid+1;
+                else
+                        last = mid-1;
+        }
+        return 0;
+}
+
+unsigned long
+search_exception_table(unsigned long addr)
+{
+	unsigned long ret;
+
+#ifndef CONFIG_MODULES
+        addr &= 0x7fffffff;  /* remove amode bit from address */
+	/* There is only the kernel to search.  */
+	ret = search_one_table(__start___ex_table, __stop___ex_table-1, addr);
+	if (ret) return FIX_PSW(ret);
+#else
+	/* The kernel is the last "module" -- no need to treat it special.  */
+	struct module *mp;
+        addr &= 0x7fffffff;  /* remove amode bit from address */
+	for (mp = module_list; mp != NULL; mp = mp->next) {
+		if (mp->ex_table_start == NULL)
+			continue;
+		ret = search_one_table(mp->ex_table_start,
+				       mp->ex_table_end - 1, addr);
+		if (ret) return FIX_PSW(ret);
+	}
+#endif
+
+	return 0;
+}