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  */
21 int 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(&to, &empty_zero_page, 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  */
49 int 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