kernel-ark/arch/um/os-Linux/tls.c
Paolo 'Blaisorblade' Giarrusso 3feb88562d [PATCH] uml: check for differences in host support
If running on a host not supporting TLS (for instance 2.4) we should report
that cleanly to the user, instead of printing not comprehensible "error 5" for
that.

Additionally, i386 and x86_64 support different ranges for
user_desc->entry_number, and we must account for that; we couldn't pass
ourselves -1 because we need to override previously existing TLS descriptors
which glibc has possibly set, so test at startup the range to use.

x86 and x86_64 existing ranges are hardcoded.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:52 -08:00

77 lines
1.4 KiB
C

#include <errno.h>
#include <sys/ptrace.h>
#include <asm/ldt.h>
#include "sysdep/tls.h"
#include "uml-config.h"
/* TLS support - we basically rely on the host's one.*/
/* In TT mode, this should be called only by the tracing thread, and makes sense
* only for PTRACE_SET_THREAD_AREA. In SKAS mode, it's used normally.
*
*/
#ifndef PTRACE_GET_THREAD_AREA
#define PTRACE_GET_THREAD_AREA 25
#endif
#ifndef PTRACE_SET_THREAD_AREA
#define PTRACE_SET_THREAD_AREA 26
#endif
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;
}
#ifdef UML_CONFIG_MODE_SKAS
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;
}
#endif
#ifdef UML_CONFIG_MODE_TT
#include "linux/unistd.h"
static _syscall1(int, get_thread_area, user_desc_t *, u_info);
static _syscall1(int, set_thread_area, user_desc_t *, u_info);
int do_set_thread_area_tt(user_desc_t *info)
{
int ret;
ret = set_thread_area(info);
if (ret < 0) {
ret = -errno;
}
return ret;
}
int do_get_thread_area_tt(user_desc_t *info)
{
int ret;
ret = get_thread_area(info);
if (ret < 0) {
ret = -errno;
}
return ret;
}
#endif /* UML_CONFIG_MODE_TT */