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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
ARC: Syscall support (no-legacy-syscall ABI)
This includes support for generic clone/for/vfork/execve
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
+228
+1
arch/arc/Kconfig
+1
arch/arc/Kconfig
+5
arch/arc/include/asm/ptrace.h
+5
arch/arc/include/asm/ptrace.h
+72
arch/arc/include/asm/syscall.h
+72
arch/arc/include/asm/syscall.h
···
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/*
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* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#ifndef _ASM_ARC_SYSCALL_H
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#define _ASM_ARC_SYSCALL_H 1
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#include <linux/err.h>
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#include <linux/sched.h>
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#include <asm/unistd.h>
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#include <asm/ptrace.h> /* in_syscall() */
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static inline long
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syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
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{
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if (user_mode(regs) && in_syscall(regs))
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return regs->orig_r8;
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else
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return -1;
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}
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static inline void
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syscall_rollback(struct task_struct *task, struct pt_regs *regs)
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{
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/* XXX: I can't fathom how pt_regs->r8 will be clobbered ? */
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regs->r8 = regs->orig_r8;
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}
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static inline long
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syscall_get_error(struct task_struct *task, struct pt_regs *regs)
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{
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/* 0 if syscall succeeded, otherwise -Errorcode */
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return IS_ERR_VALUE(regs->r0) ? regs->r0 : 0;
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}
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static inline long
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syscall_get_return_value(struct task_struct *task, struct pt_regs *regs)
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{
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return regs->r0;
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}
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static inline void
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syscall_set_return_value(struct task_struct *task, struct pt_regs *regs,
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int error, long val)
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{
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regs->r0 = (long) error ?: val;
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}
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/*
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* @i: argument index [0,5]
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* @n: number of arguments; n+i must be [1,6].
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*/
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static inline void
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syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
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unsigned int i, unsigned int n, unsigned long *args)
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{
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unsigned long *inside_ptregs = &(regs->r0);
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inside_ptregs -= i;
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BUG_ON((i + n) > 6);
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while (n--) {
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args[i++] = (*inside_ptregs);
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inside_ptregs--;
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}
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}
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#endif
+29
arch/arc/include/asm/syscalls.h
+29
arch/arc/include/asm/syscalls.h
···
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/*
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* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#ifndef _ASM_ARC_SYSCALLS_H
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#define _ASM_ARC_SYSCALLS_H 1
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#ifdef __KERNEL__
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#include <linux/compiler.h>
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#include <linux/linkage.h>
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#include <linux/types.h>
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int sys_clone_wrapper(int, int, int, int, int);
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int sys_fork_wrapper(void);
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int sys_vfork_wrapper(void);
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int sys_cacheflush(uint32_t, uint32_t uint32_t);
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int sys_arc_settls(void *);
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int sys_arc_gettls(void);
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#include <asm-generic/syscalls.h>
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#endif /* __KERNEL__ */
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#endif
+34
arch/arc/include/asm/unistd.h
+34
arch/arc/include/asm/unistd.h
···
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/*
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* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
3
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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/******** no-legacy-syscalls-ABI *******/
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#define __ARCH_WANT_SYS_EXECVE
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#define __ARCH_WANT_SYS_CLONE
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#define __ARCH_WANT_SYS_VFORK
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#define __ARCH_WANT_SYS_FORK
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#define sys_mmap2 sys_mmap_pgoff
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#include <asm-generic/unistd.h>
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#define NR_syscalls __NR_syscalls
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/* ARC specific syscall */
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#define __NR_cacheflush (__NR_arch_specific_syscall + 0)
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#define __NR_arc_settls (__NR_arch_specific_syscall + 1)
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#define __NR_arc_gettls (__NR_arch_specific_syscall + 2)
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__SYSCALL(__NR_cacheflush, sys_cacheflush)
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__SYSCALL(__NR_arc_settls, sys_arc_settls)
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__SYSCALL(__NR_arc_gettls, sys_arc_gettls)
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/* Generic syscall (fs/filesystems.c - lost in asm-generic/unistd.h */
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#define __NR_sysfs (__NR_arch_specific_syscall + 3)
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__SYSCALL(__NR_sysfs, sys_sysfs)
+27
arch/arc/kernel/entry.S
+27
arch/arc/kernel/entry.S
···
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bl @schedule_tail
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b @ret_from_exception
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ARC_EXIT ret_from_fork
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;################### Special Sys Call Wrappers ##########################
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; TBD: call do_fork directly from here
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ARC_ENTRY sys_fork_wrapper
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SAVE_CALLEE_SAVED_USER
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bl @sys_fork
579
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DISCARD_CALLEE_SAVED_USER
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b ret_from_system_call
582
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ARC_EXIT sys_fork_wrapper
583
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584
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ARC_ENTRY sys_vfork_wrapper
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SAVE_CALLEE_SAVED_USER
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bl @sys_vfork
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DISCARD_CALLEE_SAVED_USER
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b ret_from_system_call
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ARC_EXIT sys_vfork_wrapper
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ARC_ENTRY sys_clone_wrapper
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SAVE_CALLEE_SAVED_USER
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bl @sys_clone
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DISCARD_CALLEE_SAVED_USER
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b ret_from_system_call
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ARC_EXIT sys_clone_wrapper
+42
arch/arc/kernel/process.c
+42
arch/arc/kernel/process.c
···
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/*
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* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
3
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* Amit Bhor, Kanika Nema: Codito Technologies 2004
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*/
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#include <linux/errno.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/fs.h>
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#include <linux/unistd.h>
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#include <linux/ptrace.h>
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#include <linux/slab.h>
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#include <linux/syscalls.h>
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#include <linux/elf.h>
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#include <linux/tick.h>
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SYSCALL_DEFINE1(arc_settls, void *, user_tls_data_ptr)
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{
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task_thread_info(current)->thr_ptr = (unsigned int)user_tls_data_ptr;
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return 0;
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}
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/*
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* We return the user space TLS data ptr as sys-call return code
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* Ideally it should be copy to user.
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* However we can cheat by the fact that some sys-calls do return
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* absurdly high values
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* Since the tls dat aptr is not going to be in range of 0xFFFF_xxxx
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* it won't be considered a sys-call error
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* and it will be loads better than copy-to-user, which is a definite
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* D-TLB Miss
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*/
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SYSCALL_DEFINE0(arc_gettls)
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{
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return task_thread_info(current)->thr_ptr;
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}
+18
arch/arc/kernel/sys.c
+18
arch/arc/kernel/sys.c
···
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#include <linux/syscalls.h>
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#include <linux/signal.h>
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#include <linux/unistd.h>
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#include <asm/syscalls.h>
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#define sys_clone sys_clone_wrapper
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#define sys_fork sys_fork_wrapper
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#define sys_vfork sys_vfork_wrapper
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#undef __SYSCALL
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#define __SYSCALL(nr, call) [nr] = (call),
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void *sys_call_table[NR_syscalls] = {
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[0 ... NR_syscalls-1] = sys_ni_syscall,
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#include <asm/unistd.h>
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};