1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright (C) 2015-2019 ARM Limited.
4*4882a593Smuzhiyun * Original author: Dave Martin <Dave.Martin@arm.com>
5*4882a593Smuzhiyun */
6*4882a593Smuzhiyun #define _GNU_SOURCE
7*4882a593Smuzhiyun #include <assert.h>
8*4882a593Smuzhiyun #include <errno.h>
9*4882a593Smuzhiyun #include <limits.h>
10*4882a593Smuzhiyun #include <stddef.h>
11*4882a593Smuzhiyun #include <stdio.h>
12*4882a593Smuzhiyun #include <stdlib.h>
13*4882a593Smuzhiyun #include <string.h>
14*4882a593Smuzhiyun #include <getopt.h>
15*4882a593Smuzhiyun #include <unistd.h>
16*4882a593Smuzhiyun #include <sys/auxv.h>
17*4882a593Smuzhiyun #include <sys/prctl.h>
18*4882a593Smuzhiyun #include <asm/hwcap.h>
19*4882a593Smuzhiyun #include <asm/sigcontext.h>
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun static int inherit = 0;
22*4882a593Smuzhiyun static int no_inherit = 0;
23*4882a593Smuzhiyun static int force = 0;
24*4882a593Smuzhiyun static unsigned long vl;
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun static const struct option options[] = {
27*4882a593Smuzhiyun { "force", no_argument, NULL, 'f' },
28*4882a593Smuzhiyun { "inherit", no_argument, NULL, 'i' },
29*4882a593Smuzhiyun { "max", no_argument, NULL, 'M' },
30*4882a593Smuzhiyun { "no-inherit", no_argument, &no_inherit, 1 },
31*4882a593Smuzhiyun { "help", no_argument, NULL, '?' },
32*4882a593Smuzhiyun {}
33*4882a593Smuzhiyun };
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun static char const *program_name;
36*4882a593Smuzhiyun
parse_options(int argc,char ** argv)37*4882a593Smuzhiyun static int parse_options(int argc, char **argv)
38*4882a593Smuzhiyun {
39*4882a593Smuzhiyun int c;
40*4882a593Smuzhiyun char *rest;
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun program_name = strrchr(argv[0], '/');
43*4882a593Smuzhiyun if (program_name)
44*4882a593Smuzhiyun ++program_name;
45*4882a593Smuzhiyun else
46*4882a593Smuzhiyun program_name = argv[0];
47*4882a593Smuzhiyun
48*4882a593Smuzhiyun while ((c = getopt_long(argc, argv, "Mfhi", options, NULL)) != -1)
49*4882a593Smuzhiyun switch (c) {
50*4882a593Smuzhiyun case 'M': vl = SVE_VL_MAX; break;
51*4882a593Smuzhiyun case 'f': force = 1; break;
52*4882a593Smuzhiyun case 'i': inherit = 1; break;
53*4882a593Smuzhiyun case 0: break;
54*4882a593Smuzhiyun default: goto error;
55*4882a593Smuzhiyun }
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun if (inherit && no_inherit)
58*4882a593Smuzhiyun goto error;
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun if (!vl) {
61*4882a593Smuzhiyun /* vector length */
62*4882a593Smuzhiyun if (optind >= argc)
63*4882a593Smuzhiyun goto error;
64*4882a593Smuzhiyun
65*4882a593Smuzhiyun errno = 0;
66*4882a593Smuzhiyun vl = strtoul(argv[optind], &rest, 0);
67*4882a593Smuzhiyun if (*rest) {
68*4882a593Smuzhiyun vl = ULONG_MAX;
69*4882a593Smuzhiyun errno = EINVAL;
70*4882a593Smuzhiyun }
71*4882a593Smuzhiyun if (vl == ULONG_MAX && errno) {
72*4882a593Smuzhiyun fprintf(stderr, "%s: %s: %s\n",
73*4882a593Smuzhiyun program_name, argv[optind], strerror(errno));
74*4882a593Smuzhiyun goto error;
75*4882a593Smuzhiyun }
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun ++optind;
78*4882a593Smuzhiyun }
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun /* command */
81*4882a593Smuzhiyun if (optind >= argc)
82*4882a593Smuzhiyun goto error;
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun return 0;
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun error:
87*4882a593Smuzhiyun fprintf(stderr,
88*4882a593Smuzhiyun "Usage: %s [-f | --force] "
89*4882a593Smuzhiyun "[-i | --inherit | --no-inherit] "
90*4882a593Smuzhiyun "{-M | --max | <vector length>} "
91*4882a593Smuzhiyun "<command> [<arguments> ...]\n",
92*4882a593Smuzhiyun program_name);
93*4882a593Smuzhiyun return -1;
94*4882a593Smuzhiyun }
95*4882a593Smuzhiyun
main(int argc,char ** argv)96*4882a593Smuzhiyun int main(int argc, char **argv)
97*4882a593Smuzhiyun {
98*4882a593Smuzhiyun int ret = 126; /* same as sh(1) command-not-executable error */
99*4882a593Smuzhiyun long flags;
100*4882a593Smuzhiyun char *path;
101*4882a593Smuzhiyun int t, e;
102*4882a593Smuzhiyun
103*4882a593Smuzhiyun if (parse_options(argc, argv))
104*4882a593Smuzhiyun return 2; /* same as sh(1) builtin incorrect-usage */
105*4882a593Smuzhiyun
106*4882a593Smuzhiyun if (vl & ~(vl & PR_SVE_VL_LEN_MASK)) {
107*4882a593Smuzhiyun fprintf(stderr, "%s: Invalid vector length %lu\n",
108*4882a593Smuzhiyun program_name, vl);
109*4882a593Smuzhiyun return 2; /* same as sh(1) builtin incorrect-usage */
110*4882a593Smuzhiyun }
111*4882a593Smuzhiyun
112*4882a593Smuzhiyun if (!(getauxval(AT_HWCAP) & HWCAP_SVE)) {
113*4882a593Smuzhiyun fprintf(stderr, "%s: Scalable Vector Extension not present\n",
114*4882a593Smuzhiyun program_name);
115*4882a593Smuzhiyun
116*4882a593Smuzhiyun if (!force)
117*4882a593Smuzhiyun goto error;
118*4882a593Smuzhiyun
119*4882a593Smuzhiyun fputs("Going ahead anyway (--force): "
120*4882a593Smuzhiyun "This is a debug option. Don't rely on it.\n",
121*4882a593Smuzhiyun stderr);
122*4882a593Smuzhiyun }
123*4882a593Smuzhiyun
124*4882a593Smuzhiyun flags = PR_SVE_SET_VL_ONEXEC;
125*4882a593Smuzhiyun if (inherit)
126*4882a593Smuzhiyun flags |= PR_SVE_VL_INHERIT;
127*4882a593Smuzhiyun
128*4882a593Smuzhiyun t = prctl(PR_SVE_SET_VL, vl | flags);
129*4882a593Smuzhiyun if (t < 0) {
130*4882a593Smuzhiyun fprintf(stderr, "%s: PR_SVE_SET_VL: %s\n",
131*4882a593Smuzhiyun program_name, strerror(errno));
132*4882a593Smuzhiyun goto error;
133*4882a593Smuzhiyun }
134*4882a593Smuzhiyun
135*4882a593Smuzhiyun t = prctl(PR_SVE_GET_VL);
136*4882a593Smuzhiyun if (t == -1) {
137*4882a593Smuzhiyun fprintf(stderr, "%s: PR_SVE_GET_VL: %s\n",
138*4882a593Smuzhiyun program_name, strerror(errno));
139*4882a593Smuzhiyun goto error;
140*4882a593Smuzhiyun }
141*4882a593Smuzhiyun flags = PR_SVE_VL_LEN_MASK;
142*4882a593Smuzhiyun flags = t & ~flags;
143*4882a593Smuzhiyun
144*4882a593Smuzhiyun assert(optind < argc);
145*4882a593Smuzhiyun path = argv[optind];
146*4882a593Smuzhiyun
147*4882a593Smuzhiyun execvp(path, &argv[optind]);
148*4882a593Smuzhiyun e = errno;
149*4882a593Smuzhiyun if (errno == ENOENT)
150*4882a593Smuzhiyun ret = 127; /* same as sh(1) not-found error */
151*4882a593Smuzhiyun fprintf(stderr, "%s: %s: %s\n", program_name, path, strerror(e));
152*4882a593Smuzhiyun
153*4882a593Smuzhiyun error:
154*4882a593Smuzhiyun return ret; /* same as sh(1) not-executable error */
155*4882a593Smuzhiyun }
156