// SPDX-License-Identifier: GPL-2.0
|
#include <errno.h>
|
#include <linux/unistd.h>
|
|
#include <sys/ptrace.h>
|
#include <sys/syscall.h>
|
#include <unistd.h>
|
|
#include <sysdep/tls.h>
|
|
#ifndef PTRACE_GET_THREAD_AREA
|
#define PTRACE_GET_THREAD_AREA 25
|
#endif
|
|
#ifndef PTRACE_SET_THREAD_AREA
|
#define PTRACE_SET_THREAD_AREA 26
|
#endif
|
|
/* Checks whether host supports TLS, and sets *tls_min according to the value
|
* valid on the host.
|
* i386 host have it == 6; x86_64 host have it == 12, for i386 emulation. */
|
void check_host_supports_tls(int *supports_tls, int *tls_min)
|
{
|
/* Values for x86 and x86_64.*/
|
int val[] = {GDT_ENTRY_TLS_MIN_I386, GDT_ENTRY_TLS_MIN_X86_64};
|
int i;
|
|
for (i = 0; i < ARRAY_SIZE(val); i++) {
|
user_desc_t info;
|
info.entry_number = val[i];
|
|
if (syscall(__NR_get_thread_area, &info) == 0) {
|
*tls_min = val[i];
|
*supports_tls = 1;
|
return;
|
} else {
|
if (errno == EINVAL)
|
continue;
|
else if (errno == ENOSYS)
|
*supports_tls = 0;
|
return;
|
}
|
}
|
|
*supports_tls = 0;
|
}
|
|
int os_set_thread_area(user_desc_t *info, int pid)
|
{
|
int ret;
|
|
ret = ptrace(PTRACE_SET_THREAD_AREA, pid, info->entry_number,
|
(unsigned long) info);
|
if (ret < 0)
|
ret = -errno;
|
return ret;
|
}
|
|
int os_get_thread_area(user_desc_t *info, int pid)
|
{
|
int ret;
|
|
ret = ptrace(PTRACE_GET_THREAD_AREA, pid, info->entry_number,
|
(unsigned long) info);
|
if (ret < 0)
|
ret = -errno;
|
return ret;
|
}
|
