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// 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 */
}
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