Commit c0ff3c53 authored by Ralf Baechle's avatar Ralf Baechle
Browse files

MIPS: Enable HAVE_ARCH_TRACEHOOK. 



This enables /proc/<pid>/syscall and the ptrace PTRACE_GETREGSET and
PTRACE_SETREGSET operations.

Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 6a9c001b

arch/mips/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ config MIPS 
	select HAVE_PERF_EVENTS

	select PERF_USE_VMALLOC

	select HAVE_ARCH_KGDB

	select HAVE_ARCH_TRACEHOOK

	select ARCH_HAVE_CUSTOM_GPIO_H

	select HAVE_FUNCTION_TRACER

	select HAVE_FUNCTION_TRACE_MCOUNT_TEST

arch/mips/include/asm/ptrace.h

+13 −1
Original line number Diff line number Diff line
@@ -81,7 +81,6 @@ static inline long regs_return_value(struct pt_regs *regs) 


#define instruction_pointer(regs) ((regs)->cp0_epc)

#define profile_pc(regs) instruction_pointer(regs)

#define user_stack_pointer(r) ((r)->regs[29])



extern asmlinkage void syscall_trace_enter(struct pt_regs *regs);

extern asmlinkage void syscall_trace_leave(struct pt_regs *regs);
@@ -100,4 +99,17 @@ static inline void die_if_kernel(const char *str, struct pt_regs *regs) 
	(struct pt_regs *)((sp | (THREAD_SIZE - 1)) + 1 - 32) - 1;	\

})



/* Helpers for working with the user stack pointer */



static inline unsigned long user_stack_pointer(struct pt_regs *regs)

{

	return regs->regs[29];

}



static inline void user_stack_pointer_set(struct pt_regs *regs,

	unsigned long val)

{

	regs->regs[29] = val;

}



#endif /* _ASM_PTRACE_H */

arch/mips/include/asm/syscall.h

+67 −0
Original line number Diff line number Diff line 
/*

 * Access to user system call parameters and results

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 *

 * See asm-generic/syscall.h for descriptions of what we must do here.

 *

 * Copyright (C) 2012 Ralf Baechle <ralf@linux-mips.org>

 */



#ifndef __ASM_MIPS_SYSCALL_H

#define __ASM_MIPS_SYSCALL_H



#include <linux/kernel.h>

#include <linux/sched.h>

#include <linux/uaccess.h>

#include <asm/ptrace.h>



static inline long syscall_get_nr(struct task_struct *task,

				  struct pt_regs *regs)

{

	return regs->regs[2];

}



static inline unsigned long mips_get_syscall_arg(unsigned long *arg,

	struct task_struct *task, struct pt_regs *regs, unsigned int n)

{

	unsigned long usp = regs->regs[29];



	switch (n) {

	case 0: case 1: case 2: case 3:

		*arg = regs->regs[4 + n];



		return 0;



#ifdef CONFIG_32BIT

	case 4: case 5: case 6: case 7:

		return get_user(*arg, (int *)usp + 4 * n);

#endif



#ifdef CONFIG_64BIT

	case 4: case 5: case 6: case 7:

#ifdef CONFIG_MIPS32_O32

		if (test_thread_flag(TIF_32BIT_REGS))

			return get_user(*arg, (int *)usp + 4 * n);

		else

#endif

			*arg = regs->regs[4 + n];



		return 0;

#endif



	default:

		BUG();

	}

}



static inline void syscall_get_arguments(struct task_struct *task,

					 struct pt_regs *regs,

					 unsigned int i, unsigned int n,

					 unsigned long *args)

{

	unsigned long arg;

	int ret;



	while (n--)

		ret |= mips_get_syscall_arg(&arg, task, regs, i++);



	/*

	 * No way to communicate an error because this is a void function.

	 */

#if 0

	return ret;

#endif

}



extern const unsigned long sys_call_table[];

extern const unsigned long sys32_call_table[];

extern const unsigned long sysn32_call_table[];