s390/extable: add and use fixup_exception helper function

Add and use fixup_exception helper function in order to remove the
duplicated exception handler fixup code at several places.

Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

2 files changed, 16 insertions, 6 deletions

diff --git a/arch/s390/mm/extable.c b/arch/s390/mm/extable.c
index a4eb3d8aae7b..d6ca75570dcf 100644
--- a/arch/s390/mm/extable.c
+++ b/arch/s390/mm/extable.c
@@ -14,3 +14,18 @@ const struct exception_table_entry *s390_search_extables(unsigned long addr)
 	num = __stop_amode31_ex_table - __start_amode31_ex_table;
 	return search_extable(__start_amode31_ex_table, num, addr);
 }
+
+bool fixup_exception(struct pt_regs *regs)
+{
+	const struct exception_table_entry *ex;
+	ex_handler_t handler;
+
+	ex = s390_search_extables(instruction_pointer(regs));
+	if (!ex)
+		return false;
+	handler = ex_fixup_handler(ex);
+	if (unlikely(handler))
+		return handler(ex, regs);
+	regs->psw.addr = extable_fixup(ex);
+	return true;
+}
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index caa4ab0ff80a..e173b6187ad5 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -230,13 +230,8 @@ static noinline void do_sigsegv(struct pt_regs *regs, int si_code)
 
 static noinline void do_no_context(struct pt_regs *regs)
 {
-	const struct exception_table_entry *fixup;
-
-	/* Are we prepared to handle this kernel fault?  */
-	fixup = s390_search_extables(regs->psw.addr);
-	if (fixup && ex_handle(fixup, regs))
+	if (fixup_exception(regs))
 		return;
-
 	/*
 	 * Oops. The kernel tried to access some bad page. We'll have to
 	 * terminate things with extreme prejudice.