Files
cubelinux-kernel/arch/x86/um/os-Linux/tls.c
T
Greg Kroah-Hartman 598cf27219 Linux 6.19.3
Link: https://lore.kernel.org/r/20260217200002.683975158@linuxfoundation.org
Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>
Tested-by: Takeshi Ogasawara <takeshi.ogasawara@futuring-girl.com>
Tested-by: Peter Schneider <pschneider1968@googlemail.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Tested-by: Brett A C Sheffield <bacs@librecast.net>
Tested-by: Mark Brown <broonie@kernel.org>
Tested-by: Luna Jernberg <droidbittin@gmail.com>
Tested-by: Ronald Warsow <rwarsow@gmx.de>
Tested-by: Justin M. Forbes <jforbes@fedoraproject.org>
Tested-by: Ron Economos <re@w6rz.net>
Tested-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-02-19 16:33:27 +01:00

70 lines
1.4 KiB
C

// 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 <os.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;
}