arch/um/os-Linux/tls.c

   1 #include <errno.h>
   2 #include <sys/ptrace.h>
   3 #include <asm/ldt.h>
   4 #include "sysdep/tls.h"
   5 #include "uml-config.h"
   6
   7 /* TLS support - we basically rely on the host's one.*/
   8
   9 /* In TT mode, this should be called only by the tracing thread, and makes sense
  10  * only for PTRACE_SET_THREAD_AREA. In SKAS mode, it's used normally.
  11  *
  12  */
  13
  14 #ifndef PTRACE_GET_THREAD_AREA
  15 #define PTRACE_GET_THREAD_AREA 25
  16 #endif
  17
  18 #ifndef PTRACE_SET_THREAD_AREA
  19 #define PTRACE_SET_THREAD_AREA 26
  20 #endif
  21
  22 int os_set_thread_area(user_desc_t *info, int pid)
  23 {
  24         int ret;
  25
  26         ret = ptrace(PTRACE_SET_THREAD_AREA, pid, info->entry_number,
  27                      (unsigned long) info);
  28         if (ret < 0)
  29                 ret = -errno;
  30         return ret;
  31 }
  32
  33 #ifdef UML_CONFIG_MODE_SKAS
  34
  35 int os_get_thread_area(user_desc_t *info, int pid)
  36 {
  37         int ret;
  38
  39         ret = ptrace(PTRACE_GET_THREAD_AREA, pid, info->entry_number,
  40                      (unsigned long) info);
  41         if (ret < 0)
  42                 ret = -errno;
  43         return ret;
  44 }
  45
  46 #endif
  47
  48 #ifdef UML_CONFIG_MODE_TT
  49 #include "linux/unistd.h"
  50
  51 static _syscall1(int, get_thread_area, user_desc_t *, u_info);
  52 static _syscall1(int, set_thread_area, user_desc_t *, u_info);
  53
  54 int do_set_thread_area_tt(user_desc_t *info)
  55 {
  56         int ret;
  57
  58         ret = set_thread_area(info);
  59         if (ret < 0) {
  60                 ret = -errno;
  61         }
  62         return ret;
  63 }
  64
  65 int do_get_thread_area_tt(user_desc_t *info)
  66 {
  67         int ret;
  68
  69         ret = get_thread_area(info);
  70         if (ret < 0) {
  71                 ret = -errno;
  72         }
  73         return ret;
  74 }
  75
  76 #endif /* UML_CONFIG_MODE_TT */