sysdeps/unix/sysv/linux/sysdep-vdso.h

   1 /* vDSO common definition for Linux.
   2    Copyright (C) 2015-2017 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef SYSDEP_VDSO_LINUX_H
  20 # define SYSDEP_VDSO_LINUX_H
  21
  22 #define VDSO_SYMBOL(__name) __vdso_##__name
  23
  24 #ifndef INTERNAL_VSYSCALL_CALL
  25 # define INTERNAL_VSYSCALL_CALL(funcptr, err, nr, args...)                    \
  26      funcptr (args)
  27 #endif
  28
  29 #ifdef SHARED
  30
  31 # ifdef HAVE_VSYSCALL
  32
  33 #  include <libc-vdso.h>
  34
  35 #  define INLINE_VSYSCALL(name, nr, args...)                                  \
  36   ({                                                                          \
  37     __label__ out;                                                            \
  38     __label__ iserr;                                                          \
  39     INTERNAL_SYSCALL_DECL (sc_err);                                           \
  40     long int sc_ret;                                                          \
  41                                                                               \
  42     __typeof (__vdso_##name) vdsop = __vdso_##name;                           \
  43     PTR_DEMANGLE (vdsop);                                                     \
  44     if (vdsop != NULL)                                                        \
  45       {                                                                       \
  46         sc_ret = INTERNAL_VSYSCALL_CALL (vdsop, sc_err, nr, ##args);          \
  47         if (!INTERNAL_SYSCALL_ERROR_P (sc_ret, sc_err))                       \
  48           goto out;                                                           \
  49         if (INTERNAL_SYSCALL_ERRNO (sc_ret, sc_err) != ENOSYS)                \
  50           goto iserr;                                                         \
  51       }                                                                       \
  52                                                                               \
  53     sc_ret = INTERNAL_SYSCALL (name, sc_err, nr, ##args);                     \
  54     if (INTERNAL_SYSCALL_ERROR_P (sc_ret, sc_err))                            \
  55       {                                                                       \
  56       iserr:                                                                  \
  57         __set_errno (INTERNAL_SYSCALL_ERRNO (sc_ret, sc_err));                \
  58         sc_ret = -1L;                                                         \
  59       }                                                                       \
  60   out:                                                                        \
  61     sc_ret;                                                                   \
  62   })
  63
  64 #  define INTERNAL_VSYSCALL(name, err, nr, args...)                           \
  65   ({                                                                          \
  66     __label__ out;                                                            \
  67     long v_ret;                                                               \
  68                                                                               \
  69     __typeof (__vdso_##name) vdsop = __vdso_##name;                           \
  70     PTR_DEMANGLE (vdsop);                                                     \
  71     if (vdsop != NULL)                                                        \
  72       {                                                                       \
  73         v_ret = INTERNAL_VSYSCALL_CALL (vdsop, err, nr, ##args);              \
  74         if (!INTERNAL_SYSCALL_ERROR_P (v_ret, err)                            \
  75             || INTERNAL_SYSCALL_ERRNO (v_ret, err) != ENOSYS)                 \
  76           goto out;                                                           \
  77       }                                                                       \
  78     v_ret = INTERNAL_SYSCALL (name, err, nr, ##args);                         \
  79   out:                                                                        \
  80     v_ret;                                                                    \
  81   })
  82 # else
  83 #  define INLINE_VSYSCALL(name, nr, args...) \
  84     INLINE_SYSCALL (name, nr, ##args)
  85 #  define INTERNAL_VSYSCALL(name, err, nr, args...) \
  86     INTERNAL_SYSCALL (name, err, nr, ##args)
  87 # endif /* HAVE_VSYSCALL  */
  88
  89 # else /* SHARED  */
  90
  91 #  define INLINE_VSYSCALL(name, nr, args...) \
  92     INLINE_SYSCALL (name, nr, ##args)
  93 #  define INTERNAL_VSYSCALL(name, err, nr, args...) \
  94     INTERNAL_SYSCALL (name, err, nr, ##args)
  95
  96 #endif /* SHARED  */
  97
  98 #endif /* SYSDEP_VDSO_LINUX_H  */