root/arch/s390/include/asm/entry-common.h
/* 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.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)
{
        load_user_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());
}

#define arch_exit_to_user_mode_prepare arch_exit_to_user_mode_prepare

static __always_inline bool arch_in_rcu_eqs(void)
{
        if (IS_ENABLED(CONFIG_KVM))
                return current->flags & PF_VCPU;

        return false;
}

#define arch_in_rcu_eqs arch_in_rcu_eqs

#endif