1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Ptrace test for TAR, PPR, DSCR registers
4 *
5 * Copyright (C) 2015 Anshuman Khandual, IBM Corporation.
6 */
7#include "ptrace.h"
8#include "ptrace-tar.h"
9
10/* Tracer and Tracee Shared Data */
11int shm_id;
12int *cptr;
13int *pptr;
14
15void tar(void)
16{
17	unsigned long reg[3];
18	int ret;
19
20	cptr = (int *)shmat(shm_id, NULL, 0);
21	printf("%-30s TAR: %u PPR: %lx DSCR: %u\n",
22			user_write, TAR_1, PPR_1, DSCR_1);
23
24	mtspr(SPRN_TAR, TAR_1);
25	mtspr(SPRN_PPR, PPR_1);
26	mtspr(SPRN_DSCR, DSCR_1);
27
28	cptr[2] = 1;
29
30	/* Wait on parent */
31	while (!cptr[0])
32		asm volatile("" : : : "memory");
33
34	reg[0] = mfspr(SPRN_TAR);
35	reg[1] = mfspr(SPRN_PPR);
36	reg[2] = mfspr(SPRN_DSCR);
37
38	printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n",
39			user_read, reg[0], reg[1], reg[2]);
40
41	/* Unblock the parent now */
42	cptr[1] = 1;
43	shmdt((int *)cptr);
44
45	ret = validate_tar_registers(reg, TAR_2, PPR_2, DSCR_2);
46	if (ret)
47		exit(1);
48	exit(0);
49}
50
51int trace_tar(pid_t child)
52{
53	unsigned long reg[3];
54
55	FAIL_IF(start_trace(child));
56	FAIL_IF(show_tar_registers(child, reg));
57	printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n",
58			ptrace_read_running, reg[0], reg[1], reg[2]);
59
60	FAIL_IF(validate_tar_registers(reg, TAR_1, PPR_1, DSCR_1));
61	FAIL_IF(stop_trace(child));
62	return TEST_PASS;
63}
64
65int trace_tar_write(pid_t child)
66{
67	FAIL_IF(start_trace(child));
68	FAIL_IF(write_tar_registers(child, TAR_2, PPR_2, DSCR_2));
69	printf("%-30s TAR: %u PPR: %lx DSCR: %u\n",
70			ptrace_write_running, TAR_2, PPR_2, DSCR_2);
71
72	FAIL_IF(stop_trace(child));
73	return TEST_PASS;
74}
75
76int ptrace_tar(void)
77{
78	pid_t pid;
79	int ret, status;
80
81	// TAR was added in v2.07
82	SKIP_IF_MSG(!have_hwcap2(PPC_FEATURE2_ARCH_2_07), "TAR requires ISA 2.07 compatible hardware");
83
84	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 3, 0777|IPC_CREAT);
85	pid = fork();
86	if (pid < 0) {
87		perror("fork() failed");
88		return TEST_FAIL;
89	}
90
91	if (pid == 0)
92		tar();
93
94	if (pid) {
95		pptr = (int *)shmat(shm_id, NULL, 0);
96		pptr[0] = 0;
97		pptr[1] = 0;
98
99		while (!pptr[2])
100			asm volatile("" : : : "memory");
101		ret = trace_tar(pid);
102		if (ret)
103			return ret;
104
105		ret = trace_tar_write(pid);
106		if (ret)
107			return ret;
108
109		/* Unblock the child now */
110		pptr[0] = 1;
111
112		/* Wait on child */
113		while (!pptr[1])
114			asm volatile("" : : : "memory");
115
116		shmdt((int *)pptr);
117
118		ret = wait(&status);
119		shmctl(shm_id, IPC_RMID, NULL);
120		if (ret != pid) {
121			printf("Child's exit status not captured\n");
122			return TEST_PASS;
123		}
124
125		return (WIFEXITED(status) && WEXITSTATUS(status)) ? TEST_FAIL :
126			TEST_PASS;
127	}
128	return TEST_PASS;
129}
130
131int main(int argc, char *argv[])
132{
133	return test_harness(ptrace_tar, "ptrace_tar");
134}
135