aboutsummaryrefslogtreecommitdiff
path: root/tools/testing/selftests/arm64/fp/vlset.c
blob: 308d27a68226987cc7063b2479976bcb5d7a144d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2015-2019 ARM Limited.
 * Original author: Dave Martin <Dave.Martin@arm.com>
 */
#define _GNU_SOURCE
#include <assert.h>
#include <errno.h>
#include <limits.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include <unistd.h>
#include <sys/auxv.h>
#include <sys/prctl.h>
#include <asm/hwcap.h>
#include <asm/sigcontext.h>

static int inherit = 0;
static int no_inherit = 0;
static int force = 0;
static unsigned long vl;

static const struct option options[] = {
	{ "force",	no_argument, NULL, 'f' },
	{ "inherit",	no_argument, NULL, 'i' },
	{ "max",	no_argument, NULL, 'M' },
	{ "no-inherit",	no_argument, &no_inherit, 1 },
	{ "help",	no_argument, NULL, '?' },
	{}
};

static char const *program_name;

static int parse_options(int argc, char **argv)
{
	int c;
	char *rest;

	program_name = strrchr(argv[0], '/');
	if (program_name)
		++program_name;
	else
		program_name = argv[0];

	while ((c = getopt_long(argc, argv, "Mfhi", options, NULL)) != -1)
		switch (c) {
		case 'M':	vl = SVE_VL_MAX; break;
		case 'f':	force = 1; break;
		case 'i':	inherit = 1; break;
		case 0:		break;
		default:	goto error;
		}

	if (inherit && no_inherit)
		goto error;

	if (!vl) {
		/* vector length */
		if (optind >= argc)
			goto error;

		errno = 0;
		vl = strtoul(argv[optind], &rest, 0);
		if (*rest) {
			vl = ULONG_MAX;
			errno = EINVAL;
		}
		if (vl == ULONG_MAX && errno) {
			fprintf(stderr, "%s: %s: %s\n",
				program_name, argv[optind], strerror(errno));
			goto error;
		}

		++optind;
	}

	/* command */
	if (optind >= argc)
		goto error;

	return 0;

error:
	fprintf(stderr,
		"Usage: %s [-f | --force] "
		"[-i | --inherit | --no-inherit] "
		"{-M | --max | <vector length>} "
		"<command> [<arguments> ...]\n",
		program_name);
	return -1;
}

int main(int argc, char **argv)
{
	int ret = 126;	/* same as sh(1) command-not-executable error */
	long flags;
	char *path;
	int t, e;

	if (parse_options(argc, argv))
		return 2;	/* same as sh(1) builtin incorrect-usage */

	if (vl & ~(vl & PR_SVE_VL_LEN_MASK)) {
		fprintf(stderr, "%s: Invalid vector length %lu\n",
			program_name, vl);
		return 2;	/* same as sh(1) builtin incorrect-usage */
	}

	if (!(getauxval(AT_HWCAP) & HWCAP_SVE)) {
		fprintf(stderr, "%s: Scalable Vector Extension not present\n",
			program_name);

		if (!force)
			goto error;

		fputs("Going ahead anyway (--force):  "
		      "This is a debug option.  Don't rely on it.\n",
		      stderr);
	}

	flags = PR_SVE_SET_VL_ONEXEC;
	if (inherit)
		flags |= PR_SVE_VL_INHERIT;

	t = prctl(PR_SVE_SET_VL, vl | flags);
	if (t < 0) {
		fprintf(stderr, "%s: PR_SVE_SET_VL: %s\n",
			program_name, strerror(errno));
		goto error;
	}

	t = prctl(PR_SVE_GET_VL);
	if (t == -1) {
		fprintf(stderr, "%s: PR_SVE_GET_VL: %s\n",
			program_name, strerror(errno));
		goto error;
	}
	flags = PR_SVE_VL_LEN_MASK;
	flags = t & ~flags;

	assert(optind < argc);
	path = argv[optind];

	execvp(path, &argv[optind]);
	e = errno;
	if (errno == ENOENT)
		ret = 127;	/* same as sh(1) not-found error */
	fprintf(stderr, "%s: %s: %s\n", program_name, path, strerror(e));

error:
	return ret;		/* same as sh(1) not-executable error */
}