1 files changed, 68 insertions, 0 deletions
diff --git a/arch/s390/include/asm/entry-common.h b/arch/s390/include/asm/entry-common.h
new file mode 100644
index 000000000..000de2b1e
--- /dev/null
+++ b/arch/s390/include/asm/entry-common.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ARCH_S390_ENTRY_COMMON_H
+#define ARCH_S390_ENTRY_COMMON_H
+
+#include <linux/sched.h>
+#include <linux/audit.h>
+#include <linux/randomize_kstack.h>
+#include <linux/processor.h>
+#include <linux/uaccess.h>
+#include <asm/timex.h>
+#include <asm/fpu/api.h>
+#include <asm/pai.h>
+
+#define ARCH_EXIT_TO_USER_MODE_WORK (_TIF_GUARDED_STORAGE | _TIF_PER_TRAP)
+
+void do_per_trap(struct pt_regs *regs);
+
+static __always_inline void arch_enter_from_user_mode(struct pt_regs *regs)
+{
+	if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
+		debug_user_asce(0);
+
+	pai_kernel_enter(regs);
+}
+
+#define arch_enter_from_user_mode arch_enter_from_user_mode
+
+static __always_inline void arch_exit_to_user_mode_work(struct pt_regs *regs,
+							unsigned long ti_work)
+{
+	if (ti_work & _TIF_PER_TRAP) {
+		clear_thread_flag(TIF_PER_TRAP);
+		do_per_trap(regs);
+	}
+
+	if (ti_work & _TIF_GUARDED_STORAGE)
+		gs_load_bc_cb(regs);
+}
+
+#define arch_exit_to_user_mode_work arch_exit_to_user_mode_work
+
+static __always_inline void arch_exit_to_user_mode(void)
+{
+	if (test_cpu_flag(CIF_FPU))
+		__load_fpu_regs();
+
+	if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
+		debug_user_asce(1);
+
+	pai_kernel_exit(current_pt_regs());
+}
+
+#define arch_exit_to_user_mode arch_exit_to_user_mode
+
+static inline void arch_exit_to_user_mode_prepare(struct pt_regs *regs,
+						  unsigned long ti_work)
+{
+	choose_random_kstack_offset(get_tod_clock_fast() & 0xff);
+}
+
+#define arch_exit_to_user_mode_prepare arch_exit_to_user_mode_prepare
+
+static inline bool on_thread_stack(void)
+{
+	return !(((unsigned long)(current->stack) ^ current_stack_pointer) & ~(THREAD_SIZE - 1));
+}
+
+#endif