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-rw-r--r--arch/s390/mm/extable.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/arch/s390/mm/extable.c b/arch/s390/mm/extable.c
new file mode 100644
index 000000000..2aac12c97
--- /dev/null
+++ b/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;
+}