xref: /linux/arch/s390/include/asm/entry-common.h (revision f5c31bcf604db54470868f3118a60dc4a9ba8813)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef ARCH_S390_ENTRY_COMMON_H
3 #define ARCH_S390_ENTRY_COMMON_H
4 
5 #include <linux/sched.h>
6 #include <linux/audit.h>
7 #include <linux/randomize_kstack.h>
8 #include <linux/processor.h>
9 #include <linux/uaccess.h>
10 #include <asm/timex.h>
11 #include <asm/fpu.h>
12 #include <asm/pai.h>
13 
14 #define ARCH_EXIT_TO_USER_MODE_WORK (_TIF_GUARDED_STORAGE | _TIF_PER_TRAP)
15 
16 void do_per_trap(struct pt_regs *regs);
17 
18 static __always_inline void arch_enter_from_user_mode(struct pt_regs *regs)
19 {
20 	if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
21 		debug_user_asce(0);
22 
23 	pai_kernel_enter(regs);
24 }
25 
26 #define arch_enter_from_user_mode arch_enter_from_user_mode
27 
28 static __always_inline void arch_exit_to_user_mode_work(struct pt_regs *regs,
29 							unsigned long ti_work)
30 {
31 	if (ti_work & _TIF_PER_TRAP) {
32 		clear_thread_flag(TIF_PER_TRAP);
33 		do_per_trap(regs);
34 	}
35 
36 	if (ti_work & _TIF_GUARDED_STORAGE)
37 		gs_load_bc_cb(regs);
38 }
39 
40 #define arch_exit_to_user_mode_work arch_exit_to_user_mode_work
41 
42 static __always_inline void arch_exit_to_user_mode(void)
43 {
44 	load_user_fpu_regs();
45 
46 	if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
47 		debug_user_asce(1);
48 
49 	pai_kernel_exit(current_pt_regs());
50 }
51 
52 #define arch_exit_to_user_mode arch_exit_to_user_mode
53 
54 static inline void arch_exit_to_user_mode_prepare(struct pt_regs *regs,
55 						  unsigned long ti_work)
56 {
57 	choose_random_kstack_offset(get_tod_clock_fast() & 0xff);
58 }
59 
60 #define arch_exit_to_user_mode_prepare arch_exit_to_user_mode_prepare
61 
62 #endif
63