Most implementations of arch_syscall_addr() are the same, so create a default version in common code and move the one piece that differs (the syscall table) to asm/syscall.h. New arch ports don't have to waste time copying & pasting this simple function. The s390/sparc versions need to be different, so document why. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1264498803-17278-1-git-send-email-vapier@gentoo.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
		
			
				
	
	
		
			92 lines
		
	
	
	
		
			2.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			92 lines
		
	
	
	
		
			2.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Access to user system call parameters and results
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 *
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 *  Copyright IBM Corp. 2008
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 *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.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 only)
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 * as published by the Free Software Foundation.
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 */
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#ifndef _ASM_SYSCALL_H
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#define _ASM_SYSCALL_H	1
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#include <linux/sched.h>
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#include <asm/ptrace.h>
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/*
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 * The syscall table always contains 32 bit pointers since we know that the
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 * address of the function to be called is (way) below 4GB.  So the "int"
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 * type here is what we want [need] for both 32 bit and 64 bit systems.
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 */
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extern const unsigned int sys_call_table[];
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static inline long syscall_get_nr(struct task_struct *task,
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				  struct pt_regs *regs)
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{
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	return regs->svcnr ? regs->svcnr : -1;
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}
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static inline void syscall_rollback(struct task_struct *task,
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				    struct pt_regs *regs)
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{
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	regs->gprs[2] = regs->orig_gpr2;
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}
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static inline long syscall_get_error(struct task_struct *task,
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				     struct pt_regs *regs)
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{
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	return (regs->gprs[2] >= -4096UL) ? -regs->gprs[2] : 0;
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}
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static inline long syscall_get_return_value(struct task_struct *task,
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					    struct pt_regs *regs)
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{
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	return regs->gprs[2];
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}
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static inline void syscall_set_return_value(struct task_struct *task,
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					    struct pt_regs *regs,
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					    int error, long val)
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{
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	regs->gprs[2] = error ? -error : val;
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}
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static inline void syscall_get_arguments(struct task_struct *task,
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					 struct pt_regs *regs,
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					 unsigned int i, unsigned int n,
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					 unsigned long *args)
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{
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	unsigned long mask = -1UL;
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	BUG_ON(i + n > 6);
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#ifdef CONFIG_COMPAT
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	if (test_tsk_thread_flag(task, TIF_31BIT))
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		mask = 0xffffffff;
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#endif
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	if (i + n == 6)
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		args[--n] = regs->args[0] & mask;
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	while (n-- > 0)
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		if (i + n > 0)
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			args[n] = regs->gprs[2 + i + n] & mask;
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	if (i == 0)
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		args[0] = regs->orig_gpr2 & mask;
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}
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static inline void syscall_set_arguments(struct task_struct *task,
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					 struct pt_regs *regs,
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					 unsigned int i, unsigned int n,
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					 const unsigned long *args)
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{
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	BUG_ON(i + n > 6);
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	if (i + n == 6)
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		regs->args[0] = args[--n];
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	while (n-- > 0)
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		if (i + n > 0)
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			regs->gprs[2 + i + n] = args[n];
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	if (i == 0)
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		regs->orig_gpr2 = args[0];
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}
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#endif	/* _ASM_SYSCALL_H */
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