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/* Copyright (C) 2001,02,03,04 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Modification for FreeBSD contributed by Petr Salinger, 2006.
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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _KFREEBSD_X86_64_SYSDEP_H
#define _KFREEBSD_X86_64_SYSDEP_H 1
/* There is some commonality. */
#include <sysdeps/unix/x86_64/sysdep.h>
/* Defines RTLD_PRIVATE_ERRNO and USE_DL_SYSINFO. */
#include <dl-sysdep.h>
#include <tls.h>
#ifdef __ASSEMBLER__
/* We don't want the label for the error handle to be global when we define
it here. */
#ifdef PIC
# define SYSCALL_ERROR_LABEL 0f
#else
# define SYSCALL_ERROR_LABEL syscall_error
#endif
#undef PSEUDO
#define PSEUDO(name, syscall_name, args) \
.text; \
ENTRY (name) \
DO_CALL (syscall_name, args); \
jb SYSCALL_ERROR_LABEL; \
L(pseudo_end):
#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
#undef PSEUDO_ERRVAL
#define PSEUDO_ERRVAL(name, syscall_name, args) \
.text; \
ENTRY (name) \
DO_CALL (syscall_name, args); \
#undef PSEUDO_END_ERRVAL
#define PSEUDO_END_ERRVAL(name) \
END (name)
#define ret_ERRVAL ret
#ifndef PIC
#define SYSCALL_ERROR_HANDLER /* Nothing here; code in sysdep.S is used. */
#elif RTLD_PRIVATE_ERRNO
# define SYSCALL_ERROR_HANDLER \
0: \
leaq rtld_errno(%rip), %rcx; \
movl %eax, (%rcx); \
orq $-1, %rax; \
jmp L(pseudo_end);
#else
# if IS_IN (libc)
# define SYSCALL_ERROR_ERRNO __libc_errno
# else
# define SYSCALL_ERROR_ERRNO errno
# endif
# define SYSCALL_ERROR_HANDLER \
0: \
movq SYSCALL_ERROR_ERRNO@GOTTPOFF(%rip), %rcx;\
movl %eax, %fs:(%rcx); \
orq $-1, %rax; \
jmp L(pseudo_end);
#endif /* PIC */
/* The FreeBSD/amd64 kernel expects the system call parameters in
registers according to the following table:
syscall number rax
arg 1 rdi
arg 2 rsi
arg 3 rdx
arg 4 r10
arg 5 r8
arg 6 r9
The FreeBSD kernel internal syscall usage of registers:
preserved:
stack pointer rsp
C preserved rbx, rbp, r12-r15
some input params rdi, rsi
destroyed:
return value(s) rax, rdx, eflags
return address from syscall rcx
eflags from syscall r11
used internally r8-r10
Normal function call, including calls to the system call stub
functions in the libc, get the first six parameters passed in
registers and the seventh parameter and later on the stack. The
register use is as follows:
system call number in the DO_CALL macro
arg 1 rdi
arg 2 rsi
arg 3 rdx
arg 4 rcx
arg 5 r8
arg 6 r9
We have to take care that the stack is aligned to 16 bytes. When
called the stack is not aligned since the return address has just
been pushed.
*/
#undef DO_CALL
#define DO_CALL(syscall_name, args) \
DOARGS_##args \
movl $SYS_ify (syscall_name), %eax; \
syscall;
#define DOARGS_0 /* nothing */
#define DOARGS_1 /* nothing */
#define DOARGS_2 /* nothing */
#define DOARGS_3 /* nothing */
#define DOARGS_4 movq %rcx, %r10;
#define DOARGS_5 DOARGS_4
#define DOARGS_6 DOARGS_5
#define DOARGS_7 DOARGS_6
#define DOARGS_8 DOARGS_7
#else /* !__ASSEMBLER__ */
#include <syscalls-inline.h>
#endif /* __ASSEMBLER__ */
/* 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. */
# ifdef __ASSEMBLER__
# define PTR_MANGLE(reg) xorq __pointer_chk_guard_local(%rip), reg; \
rolq $17, reg
# define PTR_DEMANGLE(reg) rorq $17, reg; \
xorq __pointer_chk_guard_local(%rip), reg
# else
# define PTR_MANGLE(reg) asm ("xorq __pointer_chk_guard_local(%%rip), %0\n" \
"rolq $17, %0" \
: "=r" (reg) : "0" (reg))
# define PTR_DEMANGLE(reg) asm ("rorq $17, %0\n" \
"xorq __pointer_chk_guard_local(%%rip), %0" \
: "=r" (reg) : "0" (reg))
# endif
#else
# ifdef __ASSEMBLER__
# define PTR_MANGLE(reg) xorq %fs:POINTER_GUARD, reg; \
rolq $17, reg
# define PTR_DEMANGLE(reg) rorq $17, reg; \
xorq %fs:POINTER_GUARD, reg
# else
# define PTR_MANGLE(var) asm ("xorq %%fs:%c2, %0\n" \
"rolq $17, %0" \
: "=r" (var) \
: "0" (var), \
"i" (offsetof (tcbhead_t, \
pointer_guard)))
# define PTR_DEMANGLE(var) asm ("rorq $17, %0\n" \
"xorq %%fs:%c2, %0" \
: "=r" (var) \
: "0" (var), \
"i" (offsetof (tcbhead_t, \
pointer_guard)))
# endif
#endif
#endif /* _KFREEBSD_X86_64_SYSDEP_H */
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