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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright IBM Corp. 1999, 2009
*
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
#ifndef __ASM_SWITCH_TO_H
#define __ASM_SWITCH_TO_H
#include <linux/thread_info.h>
#include <asm/fpu/api.h>
#include <asm/ptrace.h>
#include <asm/guarded_storage.h>
extern struct task_struct *__switch_to(void *, void *);
extern void update_cr_regs(struct task_struct *task);
static inline void save_access_regs(unsigned int *acrs)
{
typedef struct { int _[NUM_ACRS]; } acrstype;
asm volatile("stam 0,15,%0" : "=Q" (*(acrstype *)acrs));
}
static inline void restore_access_regs(unsigned int *acrs)
{
typedef struct { int _[NUM_ACRS]; } acrstype;
asm volatile("lam 0,15,%0" : : "Q" (*(acrstype *)acrs));
}
#define switch_to(prev, next, last) do { \
/* save_fpu_regs() sets the CIF_FPU flag, which enforces \
* a restore of the floating point / vector registers as \
* soon as the next task returns to user space \
*/ \
save_fpu_regs(); \
save_access_regs(&prev->thread.acrs[0]); \
save_ri_cb(prev->thread.ri_cb); \
save_gs_cb(prev->thread.gs_cb); \
update_cr_regs(next); \
restore_access_regs(&next->thread.acrs[0]); \
restore_ri_cb(next->thread.ri_cb, prev->thread.ri_cb); \
restore_gs_cb(next->thread.gs_cb); \
prev = __switch_to(prev, next); \
} while (0)
#endif /* __ASM_SWITCH_TO_H */
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