glibc/sysdeps/unix/sysv/linux/tile/sysdep.h

/* Copyright (C) 2011-2015 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library.  If not, see
   <http://www.gnu.org/licenses/>.  */

#include <asm/unistd.h>
#include <sysdeps/tile/sysdep.h>
#include <sysdeps/unix/sysv/linux/generic/sysdep.h>
#include <sys/syscall.h>

#undef SYS_ify
#define SYS_ify(syscall_name)	__NR_##syscall_name


#ifdef __ASSEMBLER__

/* The actual implementation of doing a syscall. */
#define DO_CALL(syscall_name, args)                     \
  moveli TREG_SYSCALL_NR_NAME, SYS_ify(syscall_name);	\
  swint1

/* TILE Linux returns the result in r0 (or a negative errno).
   The kernel "owns" the code to decide if a given value is an error,
   and puts errno in r1 if so, or otherwise zero.  */
#define	PSEUDO(name, syscall_name, args)		\
  ENTRY	(name);						\
  DO_CALL(syscall_name, args);				\
  BNEZ r1, 0f

#define ret  jrp lr

#ifndef PIC
/* For static code, on error jump to __syscall_error directly. */
# define SYSCALL_ERROR_NAME __syscall_error
#elif IS_IN (libc) || IS_IN (libpthread)
/* Use the internal name for libc/libpthread shared objects. */
# define SYSCALL_ERROR_NAME __GI___syscall_error
#else
/* Otherwise, on error do a full PLT jump. */
# define SYSCALL_ERROR_NAME plt(__syscall_error)
#endif

#define	PSEUDO_END(name)				\
0:							\
  j SYSCALL_ERROR_NAME;					\
  END (name)

#define	PSEUDO_NOERRNO(name, syscall_name, args)	\
  ENTRY	(name);						\
  DO_CALL(syscall_name, args)

#define ret_NOERRNO  jrp lr

#define	PSEUDO_END_NOERRNO(name) \
  END (name)

/* Convenience wrappers. */
#define SYSCALL__(name, args)   PSEUDO (__##name, name, args)
#define SYSCALL(name, args)   PSEUDO (name, name, args)

#else /* not __ASSEMBLER__ */

#include <errno.h>

/* Define a macro which expands inline into the wrapper code for a system
   call.  */
# undef INLINE_SYSCALL
# define INLINE_SYSCALL(name, nr, args...) \
  ({                                                                    \
    INTERNAL_SYSCALL_DECL (err);                                        \
    unsigned long val = INTERNAL_SYSCALL (name, err, nr, args);         \
    if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (val, err), 0))      \
      {                                                                 \
	__set_errno (INTERNAL_SYSCALL_ERRNO (val, err));                \
        val = -1;                                                       \
      }                                                                 \
    (long) val; })

#undef INTERNAL_SYSCALL
#define INTERNAL_SYSCALL(name, err, nr, args...)        \
  internal_syscall##nr (SYS_ify (name), err, args)

#undef INTERNAL_SYSCALL_NCS
#define INTERNAL_SYSCALL_NCS(number, err, nr, args...)  \
  internal_syscall##nr (number, err, args)

#undef INTERNAL_SYSCALL_DECL
#define INTERNAL_SYSCALL_DECL(err) int err

#undef INTERNAL_SYSCALL_ERROR_P
#define INTERNAL_SYSCALL_ERROR_P(val, err) ({ (void) (val); (err) != 0; })

#undef INTERNAL_SYSCALL_ERRNO
#define INTERNAL_SYSCALL_ERRNO(val, err) ({ (void) (val); (err); })

#define internal_syscall0(num, err, dummy...)                           \
  ({                                                                    \
    long _sys_result, __SYSCALL_CLOBBER_DECLS;                          \
    __asm__ __volatile__ (                                              \
      "swint1"                                                          \
      : "=R00" (_sys_result), "=R01" (err), __SYSCALL_CLOBBER_OUTPUTS   \
      : "R10" (num)                                                     \
      : __SYSCALL_CLOBBERS);                                            \
    _sys_result;                                                        \
  })

#define internal_syscall1(num, err, arg0)                               \
  ({                                                                    \
    long _sys_result, __SYSCALL_CLOBBER_DECLS;                          \
    __asm__ __volatile__ (                                              \
      "swint1"                                                          \
      : "=R00" (_sys_result), "=R01" (err), __SYSCALL_CLOBBER_OUTPUTS   \
      : "R10" (num), "R00" (arg0)                                       \
      : __SYSCALL_CLOBBERS);                                            \
    _sys_result;                                                        \
  })

#define internal_syscall2(num, err, arg0, arg1)                         \
  ({                                                                    \
    long _sys_result, __SYSCALL_CLOBBER_DECLS;                          \
    __asm__ __volatile__ (                                              \
      "swint1"                                                          \
      : "=R00" (_sys_result), "=R01" (err), __SYSCALL_CLOBBER_OUTPUTS   \
      : "R10" (num), "R00" (arg0), "R01" (arg1)                         \
      : __SYSCALL_CLOBBERS);                                            \
    _sys_result;                                                        \
  })

#define internal_syscall3(num, err, arg0, arg1, arg2)                   \
  ({                                                                    \
    long _sys_result, __SYSCALL_CLOBBER_DECLS;                          \
    __asm__ __volatile__ (                                              \
      "swint1"                                                          \
      : "=R00" (_sys_result), "=R01" (err), __SYSCALL_CLOBBER_OUTPUTS   \
      : "R10" (num), "R00" (arg0), "R01" (arg1), "R02" (arg2)           \
      : __SYSCALL_CLOBBERS);                                            \
    _sys_result;                                                        \
  })

#define internal_syscall4(num, err, arg0, arg1, arg2, arg3)             \
  ({                                                                    \
    long _sys_result, __SYSCALL_CLOBBER_DECLS;                          \
    __asm__ __volatile__ (                                              \
      "swint1"                                                          \
      : "=R00" (_sys_result), "=R01" (err), __SYSCALL_CLOBBER_OUTPUTS   \
      : "R10" (num), "R00" (arg0), "R01" (arg1), "R02" (arg2),          \
        "R03" (arg3)                                                    \
      : __SYSCALL_CLOBBERS);                                            \
    _sys_result;                                                        \
  })

#define internal_syscall5(num, err, arg0, arg1, arg2, arg3, arg4)       \
  ({                                                                    \
    long _sys_result, __SYSCALL_CLOBBER_DECLS;                          \
    __asm__ __volatile__ (                                              \
      "swint1"                                                          \
      : "=R00" (_sys_result), "=R01" (err), __SYSCALL_CLOBBER_OUTPUTS   \
      : "R10" (num), "R00" (arg0), "R01" (arg1), "R02" (arg2),          \
        "R03" (arg3), "R04" (arg4)                                      \
      : __SYSCALL_CLOBBERS);                                            \
    _sys_result;                                                        \
  })

#define internal_syscall6(num, err, arg0, arg1, arg2, arg3, arg4, arg5) \
  ({                                                                    \
    long _sys_result, __SYSCALL_CLOBBER_DECLS;                          \
    __asm__ __volatile__ (                                              \
      "swint1"                                                          \
      : "=R00" (_sys_result), "=R01" (err), __SYSCALL_CLOBBER_OUTPUTS   \
      : "R10" (num), "R00" (arg0), "R01" (arg1), "R02" (arg2),          \
        "R03" (arg3), "R04" (arg4), "R05" (arg5)                        \
      : __SYSCALL_CLOBBERS);                                            \
    _sys_result;                                                        \
  })

#undef __SYSCALL_CLOBBERS
#define __SYSCALL_CLOBBERS                                      \
  "r6",  "r7",                                                  \
    "r8",  "r9",        "r11", "r12", "r13", "r14", "r15",      \
    "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",     \
    "r24", "r25", "r26", "r27", "r28", "r29", "memory"

/* gcc doesn't seem to allow an input operand to be clobbered, so we
   fake it with dummy outputs. */
#define __SYSCALL_CLOBBER_DECLS                                         \
  _clobber_r2, _clobber_r3, _clobber_r4, _clobber_r5, _clobber_r10

#define __SYSCALL_CLOBBER_OUTPUTS                                       \
  "=R02" (_clobber_r2), "=R03" (_clobber_r3), "=R04" (_clobber_r4),     \
    "=R05" (_clobber_r5), "=R10" (_clobber_r10)

/* This version is for kernels that implement system calls that
   behave like function calls as far as register saving.
   It falls back to the syscall in the case that the vDSO doesn't
   exist or fails for ENOSYS */
# ifdef SHARED
#  define INLINE_VSYSCALL(name, nr, args...) \
  ({									      \
    __label__ out;							      \
    __label__ iserr;							      \
    INTERNAL_SYSCALL_DECL (sc_err);					      \
    long int sc_ret;							      \
									      \
    __typeof (__vdso_##name) vdsop = __vdso_##name;			      \
    if (vdsop != NULL)							      \
      {									      \
        struct syscall_return_value rv = vdsop (args);			      \
        sc_ret = rv.value;						      \
        sc_err = rv.error;						      \
        if (!INTERNAL_SYSCALL_ERROR_P (sc_ret, sc_err))			      \
          goto out;							      \
        if (INTERNAL_SYSCALL_ERRNO (sc_ret, sc_err) != ENOSYS)		      \
          goto iserr;							      \
      }									      \
									      \
    sc_ret = INTERNAL_SYSCALL (name, sc_err, nr, ##args);		      \
    if (INTERNAL_SYSCALL_ERROR_P (sc_ret, sc_err))			      \
      {									      \
      iserr:								      \
        __set_errno (INTERNAL_SYSCALL_ERRNO (sc_ret, sc_err));		      \
        sc_ret = -1L;							      \
      }									      \
  out:									      \
    sc_ret;								      \
  })
#  define INTERNAL_VSYSCALL(name, err, nr, args...) \
  ({									      \
    __label__ out;							      \
    long int v_ret;							      \
									      \
    __typeof (__vdso_##name) vdsop = __vdso_##name;			      \
    if (vdsop != NULL)							      \
      {									      \
        struct syscall_return_value rv = vdsop (args);			      \
        v_ret = rv.value;						      \
        err = rv.error;							      \
        if (!INTERNAL_SYSCALL_ERROR_P (v_ret, err)			      \
            || INTERNAL_SYSCALL_ERRNO (v_ret, err) != ENOSYS)		      \
          goto out;							      \
      }									      \
    v_ret = INTERNAL_SYSCALL (name, err, nr, ##args);			      \
  out:									      \
    v_ret;								      \
  })

# else
#  define INLINE_VSYSCALL(name, nr, args...) \
  INLINE_SYSCALL (name, nr, ##args)
#  define INTERNAL_VSYSCALL(name, err, nr, args...) \
  INTERNAL_SYSCALL (name, err, nr, ##args)
# endif
#endif /* not __ASSEMBLER__ */

/* List of system calls which are supported as vsyscalls.  */
#define HAVE_CLOCK_GETTIME_VSYSCALL	1

/* Pointer mangling support.  */
#if IS_IN (rtld)
/* We cannot use the thread descriptor because in ld.so we use setjmp
   earlier than the descriptor is initialized.  */
#else
# ifdef __ASSEMBLER__
#  define PTR_MANGLE(reg, tmpreg) \
	ADDLI_PTR tmpreg, pt, POINTER_GUARD; \
	LD	tmpreg, tmpreg; \
	xor	reg, tmpreg, reg
#  define PTR_DEMANGLE(reg, tmpreg) PTR_MANGLE (reg, tmpreg)
# else
#  define PTR_MANGLE(var) \
  (var) = (__typeof (var)) ((uintptr_t) (var) ^ THREAD_GET_POINTER_GUARD ())
#  define PTR_DEMANGLE(var)	PTR_MANGLE (var)
# endif
#endif