| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | /* |
| 3 | * Copyright IBM Corp. 1999, 2009 |
| 4 | * |
| 5 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> |
| 6 | */ |
| 7 | |
| 8 | #ifndef __ASM_SWITCH_TO_H |
| 9 | #define __ASM_SWITCH_TO_H |
| 10 | |
| 11 | #include <linux/thread_info.h> |
| 12 | #include <asm/fpu/api.h> |
| 13 | #include <asm/ptrace.h> |
| 14 | #include <asm/guarded_storage.h> |
| 15 | |
| 16 | extern struct task_struct *__switch_to(void *, void *); |
| 17 | extern void update_cr_regs(struct task_struct *task); |
| 18 | |
| 19 | static inline void save_access_regs(unsigned int *acrs) |
| 20 | { |
| 21 | typedef struct { int _[NUM_ACRS]; } acrstype; |
| 22 | |
| 23 | asm volatile("stam 0,15,%0" : "=Q" (*(acrstype *)acrs)); |
| 24 | } |
| 25 | |
| 26 | static inline void restore_access_regs(unsigned int *acrs) |
| 27 | { |
| 28 | typedef struct { int _[NUM_ACRS]; } acrstype; |
| 29 | |
| 30 | asm volatile("lam 0,15,%0" : : "Q" (*(acrstype *)acrs)); |
| 31 | } |
| 32 | |
| 33 | #define switch_to(prev, next, last) do { \ |
| 34 | /* save_fpu_regs() sets the CIF_FPU flag, which enforces \ |
| 35 | * a restore of the floating point / vector registers as \ |
| 36 | * soon as the next task returns to user space \ |
| 37 | */ \ |
| 38 | save_fpu_regs(); \ |
| 39 | save_access_regs(&prev->thread.acrs[0]); \ |
| 40 | save_ri_cb(prev->thread.ri_cb); \ |
| 41 | save_gs_cb(prev->thread.gs_cb); \ |
| 42 | update_cr_regs(next); \ |
| 43 | restore_access_regs(&next->thread.acrs[0]); \ |
| 44 | restore_ri_cb(next->thread.ri_cb, prev->thread.ri_cb); \ |
| 45 | restore_gs_cb(next->thread.gs_cb); \ |
| 46 | prev = __switch_to(prev, next); \ |
| 47 | } while (0) |
| 48 | |
| 49 | #endif /* __ASM_SWITCH_TO_H */ |