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/* Copyright (C) 2005-2016 Free Software Foundation, Inc.
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/>. */
#ifndef _LINUX_AARCH64_SYSDEP_H
#define _LINUX_AARCH64_SYSDEP_H 1
#include <common/sysdep.h>
#include <sys/syscall.h>
/* In order to get __set_errno() definition in INLINE_SYSCALL. */
#ifndef __ASSEMBLER__
#include <errno.h>
#endif
/* For Linux we can use the system call table in the header file
/usr/include/asm/unistd.h
of the kernel. But these symbols do not follow the SYS_* syntax
so we have to redefine the `SYS_ify' macro here. */
#undef SYS_ify
#define SYS_ify(syscall_name) (__NR_##syscall_name)
#ifdef __ASSEMBLER__
#define ASM_SIZE_DIRECTIVE(name) .size name,.-name
/* Local label name for asm code. */
#ifndef L
# define L(name) .L##name
#endif
/* Define an entry point visible from C. */
#define ENTRY(name) \
.globl C_SYMBOL_NAME(name); \
.type C_SYMBOL_NAME(name),%function; \
.align 4; \
C_LABEL(name) \
cfi_startproc;
/* Define an entry point visible from C. */
#define ENTRY_ALIGN(name, align) \
.globl C_SYMBOL_NAME(name); \
.type C_SYMBOL_NAME(name),%function; \
.p2align align; \
C_LABEL(name) \
cfi_startproc;
#undef END
#define END(name) \
cfi_endproc; \
ASM_SIZE_DIRECTIVE(name)
/* Linux uses a negative return value to indicate syscall errors,
unlike most Unices, which use the condition codes' carry flag.
Since version 2.1 the return value of a system call might be
negative even if the call succeeded. E.g., the `lseek' system call
might return a large offset. Therefore we must not anymore test
for < 0, but test for a real error by making sure the value in R0
is a real error number. Linus said he will make sure the no syscall
returns a value in -1 .. -4095 as a valid result so we can safely
test with -4095. */
# undef PSEUDO
# define PSEUDO(name, syscall_name, args) \
.text; \
ENTRY (name); \
DO_CALL (syscall_name, args); \
cmn x0, #4095; \
b.cs .Lsyscall_error;
# undef PSEUDO_END
# define PSEUDO_END(name) \
SYSCALL_ERROR_HANDLER \
END (name)
# undef PSEUDO_NOERRNO
# define PSEUDO_NOERRNO(name, syscall_name, args) \
.text; \
ENTRY (name); \
DO_CALL (syscall_name, args);
# undef PSEUDO_END_NOERRNO
# define PSEUDO_END_NOERRNO(name) \
END (name)
# define ret_NOERRNO ret
/* The function has to return the error code. */
# undef PSEUDO_ERRVAL
# define PSEUDO_ERRVAL(name, syscall_name, args) \
.text; \
ENTRY (name) \
DO_CALL (syscall_name, args); \
neg x0, x0
# undef PSEUDO_END_ERRVAL
# define PSEUDO_END_ERRVAL(name) \
END (name)
# define ret_ERRVAL ret
#if defined _LIBC_REENTRANT
# if defined USE___THREAD
# define SYSCALL_ERROR_ERRNO errno
# endif
#endif
#if defined USE___THREAD
# define SYSCALL_ERROR .Lsyscall_error
# define SYSCALL_ERROR_HANDLER \
.Lsyscall_error: \
adrp x1, :gottprel:SYSCALL_ERROR_ERRNO; \
neg w2, w0; \
ldr x1, [x1, :gottprel_lo12:SYSCALL_ERROR_ERRNO]; \
mrs x3, tpidr_el0; \
mov x0, -1; \
str w2, [x1, x3]; \
ret;
#else
# define SYSCALL_ERROR __syscall_error
# define SYSCALL_ERROR_HANDLER \
.Lsyscall_error: \
b __syscall_error;
#endif
# undef DO_CALL
# define DO_CALL(syscall_name, args) \
mov x8, SYS_ify (syscall_name); \
svc 0
#endif /* __ASSEMBLER__ */
#endif /* linux/aarch64/sysdep.h */
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