1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/perf_event.h>
 3#include <linux/perf_regs.h>
 4#include <linux/kernel.h>
 5#include <linux/errno.h>
 6#include <linux/bug.h>
 7#include <asm/ptrace.h>
 8#include <asm/fpu/api.h>
 9#include <asm/fpu/types.h>
10
11u64 perf_reg_value(struct pt_regs *regs, int idx)
12{
13	freg_t fp;
14
15	if (idx >= PERF_REG_S390_R0 && idx <= PERF_REG_S390_R15)
16		return regs->gprs[idx];
17
18	if (idx >= PERF_REG_S390_FP0 && idx <= PERF_REG_S390_FP15) {
19		if (!user_mode(regs))
20			return 0;
21
22		idx -= PERF_REG_S390_FP0;
23		if (cpu_has_vx())
24			fp = *(freg_t *)(current->thread.fpu.vxrs + idx);
25		else
26			fp = current->thread.fpu.fprs[idx];
27		return fp.ui;
28	}
29
30	if (idx == PERF_REG_S390_MASK)
31		return regs->psw.mask;
32	if (idx == PERF_REG_S390_PC)
33		return regs->psw.addr;
34
35	WARN_ON_ONCE((u32)idx >= PERF_REG_S390_MAX);
36	return 0;
37}
38
39#define REG_RESERVED (~((1UL << PERF_REG_S390_MAX) - 1))
40
41int perf_reg_validate(u64 mask)
42{
43	if (!mask || mask & REG_RESERVED)
44		return -EINVAL;
45
46	return 0;
47}
48
49u64 perf_reg_abi(struct task_struct *task)
50{
51	if (test_tsk_thread_flag(task, TIF_31BIT))
52		return PERF_SAMPLE_REGS_ABI_32;
53
54	return PERF_SAMPLE_REGS_ABI_64;
55}
56
57void perf_get_regs_user(struct perf_regs *regs_user,
58			struct pt_regs *regs)
59{
60	/*
61	 * Use the regs from the first interruption and let
62	 * perf_sample_regs_intr() handle interrupts (regs == get_irq_regs()).
63	 *
64	 * Also save FPU registers for user-space tasks only.
65	 */
66	regs_user->regs = task_pt_regs(current);
67	if (user_mode(regs_user->regs))
68		save_fpu_regs();
69	regs_user->abi = perf_reg_abi(current);
70}