s390/exceptions: switch to relative exception table entries

This is the s390 port of 70627654 "x86, extable: Switch to relative
exception table entries".
Reduces the size of our exception tables by 50% on 64 bit builds.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 14 insertions, 1 deletions

diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h
index a8ab18b18b54..34268df959a3 100644
--- a/arch/s390/include/asm/uaccess.h
+++ b/arch/s390/include/asm/uaccess.h
@@ -76,9 +76,22 @@ static inline int __range_ok(unsigned long addr, unsigned long size)
 
 struct exception_table_entry
 {
-        unsigned long insn, fixup;
+        int insn, fixup;
 };
 
+static inline unsigned long extable_insn(const struct exception_table_entry *x)
+{
+        return (unsigned long)&x->insn + x->insn;
+}
+
+static inline unsigned long extable_fixup(const struct exception_table_entry *x)
+{
+        return (unsigned long)&x->fixup + x->fixup;
+}
+
+#define ARCH_HAS_SORT_EXTABLE
+#define ARCH_HAS_SEARCH_EXTABLE
+
 struct uaccess_ops {
         size_t (*copy_from_user)(size_t, const void __user *, void *);
         size_t (*copy_from_user_small)(size_t, const void __user *, void *);