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Diffstat (limited to '')
| -rw-r--r-- | arch/s390/include/asm/switch_to.h | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/arch/s390/include/asm/switch_to.h b/arch/s390/include/asm/switch_to.h new file mode 100644 index 000000000..c61b2cc1a --- /dev/null +++ b/arch/s390/include/asm/switch_to.h @@ -0,0 +1,49 @@ +/* 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 */ |