1// SPDX-License-Identifier: GPL-2.0-or-later
2
3#include <linux/regset.h>
4
5#include <asm/switch_to.h>
6
7#include "ptrace-decl.h"
8
9/*
10 * Regardless of transactions, 'fp_state' holds the current running
11 * value of all FPR registers and 'ckfp_state' holds the last checkpointed
12 * value of all FPR registers for the current transaction.
13 *
14 * Userspace interface buffer layout:
15 *
16 * struct data {
17 * u64 fpr[32];
18 * u64 fpscr;
19 * };
20 */
21int fpr_get(struct task_struct *target, const struct user_regset *regset,
22 struct membuf to)
23{
24#ifdef CONFIG_PPC_FPU_REGS
25 BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
26 offsetof(struct thread_fp_state, fpr[32]));
27
28 flush_fp_to_thread(target);
29
30 return membuf_write(&to, &target->thread.fp_state, 33 * sizeof(u64));
31#else
32 return membuf_write(s: &to, v: &empty_zero_page, size: 33 * sizeof(u64));
33#endif
34}
35
36/*
37 * Regardless of transactions, 'fp_state' holds the current running
38 * value of all FPR registers and 'ckfp_state' holds the last checkpointed
39 * value of all FPR registers for the current transaction.
40 *
41 * Userspace interface buffer layout:
42 *
43 * struct data {
44 * u64 fpr[32];
45 * u64 fpscr;
46 * };
47 *
48 */
49int fpr_set(struct task_struct *target, const struct user_regset *regset,
50 unsigned int pos, unsigned int count,
51 const void *kbuf, const void __user *ubuf)
52{
53#ifdef CONFIG_PPC_FPU_REGS
54 BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
55 offsetof(struct thread_fp_state, fpr[32]));
56
57 flush_fp_to_thread(target);
58
59 return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
60 &target->thread.fp_state, 0, -1);
61#else
62 return 0;
63#endif
64}
65

source code of linux/arch/powerpc/kernel/ptrace/ptrace-novsx.c