xref: /openbmc/linux/arch/s390/include/asm/switch_to.h (revision 4f6cce39)
1 /*
2  * Copyright IBM Corp. 1999, 2009
3  *
4  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
5  */
6 
7 #ifndef __ASM_SWITCH_TO_H
8 #define __ASM_SWITCH_TO_H
9 
10 #include <linux/thread_info.h>
11 #include <asm/fpu/api.h>
12 #include <asm/ptrace.h>
13 
14 extern struct task_struct *__switch_to(void *, void *);
15 extern void update_cr_regs(struct task_struct *task);
16 
17 static inline void save_access_regs(unsigned int *acrs)
18 {
19 	typedef struct { int _[NUM_ACRS]; } acrstype;
20 
21 	asm volatile("stam 0,15,%0" : "=Q" (*(acrstype *)acrs));
22 }
23 
24 static inline void restore_access_regs(unsigned int *acrs)
25 {
26 	typedef struct { int _[NUM_ACRS]; } acrstype;
27 
28 	asm volatile("lam 0,15,%0" : : "Q" (*(acrstype *)acrs));
29 }
30 
31 #define switch_to(prev,next,last) do {					\
32 	if (prev->mm) {							\
33 		save_fpu_regs();					\
34 		save_access_regs(&prev->thread.acrs[0]);		\
35 		save_ri_cb(prev->thread.ri_cb);				\
36 	}								\
37 	if (next->mm) {							\
38 		update_cr_regs(next);					\
39 		set_cpu_flag(CIF_FPU);					\
40 		restore_access_regs(&next->thread.acrs[0]);		\
41 		restore_ri_cb(next->thread.ri_cb, prev->thread.ri_cb);	\
42 	}								\
43 	prev = __switch_to(prev,next);					\
44 } while (0)
45 
46 #endif /* __ASM_SWITCH_TO_H */
47