unicore32 additional architecture files: ptrace handling

This patch adds ptrace support.

Changed from previous version:
    1. disable arch_has_single_step and remove single-step instruction handler
    2. add 'Ross Biro 1/23/92' contributor information
    3. clean unused codes

Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This commit is contained in:
GuanXuetao 2011-01-15 18:21:56 +08:00
parent d9bc15794d
commit 6dea1ba1c8
2 changed files with 282 additions and 0 deletions

View File

@ -0,0 +1,133 @@
/*
* linux/arch/unicore32/include/asm/ptrace.h
*
* Code specific to PKUnity SoC and UniCore ISA
*
* Copyright (C) 2001-2010 GUAN Xue-tao
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __UNICORE_PTRACE_H__
#define __UNICORE_PTRACE_H__
#define PTRACE_GET_THREAD_AREA 22
/*
* PSR bits
*/
#define USER_MODE 0x00000010
#define REAL_MODE 0x00000011
#define INTR_MODE 0x00000012
#define PRIV_MODE 0x00000013
#define ABRT_MODE 0x00000017
#define EXTN_MODE 0x0000001b
#define SUSR_MODE 0x0000001f
#define MODE_MASK 0x0000001f
#define PSR_R_BIT 0x00000040
#define PSR_I_BIT 0x00000080
#define PSR_V_BIT 0x10000000
#define PSR_C_BIT 0x20000000
#define PSR_Z_BIT 0x40000000
#define PSR_S_BIT 0x80000000
/*
* Groups of PSR bits
*/
#define PSR_f 0xff000000 /* Flags */
#define PSR_c 0x000000ff /* Control */
#ifndef __ASSEMBLY__
/*
* This struct defines the way the registers are stored on the
* stack during a system call. Note that sizeof(struct pt_regs)
* has to be a multiple of 8.
*/
struct pt_regs {
unsigned long uregs[34];
};
#define UCreg_asr uregs[32]
#define UCreg_pc uregs[31]
#define UCreg_lr uregs[30]
#define UCreg_sp uregs[29]
#define UCreg_ip uregs[28]
#define UCreg_fp uregs[27]
#define UCreg_26 uregs[26]
#define UCreg_25 uregs[25]
#define UCreg_24 uregs[24]
#define UCreg_23 uregs[23]
#define UCreg_22 uregs[22]
#define UCreg_21 uregs[21]
#define UCreg_20 uregs[20]
#define UCreg_19 uregs[19]
#define UCreg_18 uregs[18]
#define UCreg_17 uregs[17]
#define UCreg_16 uregs[16]
#define UCreg_15 uregs[15]
#define UCreg_14 uregs[14]
#define UCreg_13 uregs[13]
#define UCreg_12 uregs[12]
#define UCreg_11 uregs[11]
#define UCreg_10 uregs[10]
#define UCreg_09 uregs[9]
#define UCreg_08 uregs[8]
#define UCreg_07 uregs[7]
#define UCreg_06 uregs[6]
#define UCreg_05 uregs[5]
#define UCreg_04 uregs[4]
#define UCreg_03 uregs[3]
#define UCreg_02 uregs[2]
#define UCreg_01 uregs[1]
#define UCreg_00 uregs[0]
#define UCreg_ORIG_00 uregs[33]
#ifdef __KERNEL__
#define user_mode(regs) \
(processor_mode(regs) == USER_MODE)
#define processor_mode(regs) \
((regs)->UCreg_asr & MODE_MASK)
#define interrupts_enabled(regs) \
(!((regs)->UCreg_asr & PSR_I_BIT))
#define fast_interrupts_enabled(regs) \
(!((regs)->UCreg_asr & PSR_R_BIT))
/* Are the current registers suitable for user mode?
* (used to maintain security in signal handlers)
*/
static inline int valid_user_regs(struct pt_regs *regs)
{
unsigned long mode = regs->UCreg_asr & MODE_MASK;
/*
* Always clear the R (REAL) bits
*/
regs->UCreg_asr &= ~(PSR_R_BIT);
if ((regs->UCreg_asr & PSR_I_BIT) == 0) {
if (mode == USER_MODE)
return 1;
}
/*
* Force ASR to something logical...
*/
regs->UCreg_asr &= PSR_f | USER_MODE;
return 0;
}
#define instruction_pointer(regs) ((regs)->UCreg_pc)
#endif /* __KERNEL__ */
#endif /* __ASSEMBLY__ */
#endif

View File

@ -0,0 +1,149 @@
/*
* linux/arch/unicore32/kernel/ptrace.c
*
* Code specific to PKUnity SoC and UniCore ISA
*
* Copyright (C) 2001-2010 GUAN Xue-tao
*
* By Ross Biro 1/23/92
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/ptrace.h>
#include <linux/signal.h>
#include <linux/uaccess.h>
/*
* this routine will get a word off of the processes privileged stack.
* the offset is how far from the base addr as stored in the THREAD.
* this routine assumes that all the privileged stacks are in our
* data space.
*/
static inline long get_user_reg(struct task_struct *task, int offset)
{
return task_pt_regs(task)->uregs[offset];
}
/*
* this routine will put a word on the processes privileged stack.
* the offset is how far from the base addr as stored in the THREAD.
* this routine assumes that all the privileged stacks are in our
* data space.
*/
static inline int
put_user_reg(struct task_struct *task, int offset, long data)
{
struct pt_regs newregs, *regs = task_pt_regs(task);
int ret = -EINVAL;
newregs = *regs;
newregs.uregs[offset] = data;
if (valid_user_regs(&newregs)) {
regs->uregs[offset] = data;
ret = 0;
}
return ret;
}
/*
* Called by kernel/ptrace.c when detaching..
*/
void ptrace_disable(struct task_struct *child)
{
}
/*
* We actually access the pt_regs stored on the kernel stack.
*/
static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
unsigned long __user *ret)
{
unsigned long tmp;
tmp = 0;
if (off < sizeof(struct pt_regs))
tmp = get_user_reg(tsk, off >> 2);
return put_user(tmp, ret);
}
/*
* We actually access the pt_regs stored on the kernel stack.
*/
static int ptrace_write_user(struct task_struct *tsk, unsigned long off,
unsigned long val)
{
if (off >= sizeof(struct pt_regs))
return 0;
return put_user_reg(tsk, off >> 2, val);
}
long arch_ptrace(struct task_struct *child, long request,
unsigned long addr, unsigned long data)
{
int ret;
unsigned long __user *datap = (unsigned long __user *) data;
switch (request) {
case PTRACE_PEEKUSR:
ret = ptrace_read_user(child, addr, datap);
break;
case PTRACE_POKEUSR:
ret = ptrace_write_user(child, addr, data);
break;
case PTRACE_GET_THREAD_AREA:
ret = put_user(task_pt_regs(child)->UCreg_16,
datap);
break;
default:
ret = ptrace_request(child, request, addr, data);
break;
}
return ret;
}
asmlinkage int syscall_trace(int why, struct pt_regs *regs, int scno)
{
unsigned long ip;
if (!test_thread_flag(TIF_SYSCALL_TRACE))
return scno;
if (!(current->ptrace & PT_PTRACED))
return scno;
/*
* Save IP. IP is used to denote syscall entry/exit:
* IP = 0 -> entry, = 1 -> exit
*/
ip = regs->UCreg_ip;
regs->UCreg_ip = why;
current_thread_info()->syscall = scno;
/* the 0x80 provides a way for the tracing parent to distinguish
between a syscall stop and SIGTRAP delivery */
ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
? 0x80 : 0));
/*
* this isn't the same as continuing with a signal, but it will do
* for normal use. strace only continues with a signal if the
* stopping signal is not SIGTRAP. -brl
*/
if (current->exit_code) {
send_sig(current->exit_code, current, 1);
current->exit_code = 0;
}
regs->UCreg_ip = ip;
return current_thread_info()->syscall;
}