2 * linux/arch/unicore32/kernel/ptrace.c
4 * Code specific to PKUnity SoC and UniCore ISA
6 * Copyright (C) 2001-2010 GUAN Xue-tao
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
14 #include <linux/kernel.h>
15 #include <linux/ptrace.h>
16 #include <linux/signal.h>
17 #include <linux/uaccess.h>
20 * this routine will get a word off of the processes privileged stack.
21 * the offset is how far from the base addr as stored in the THREAD.
22 * this routine assumes that all the privileged stacks are in our
25 static inline long get_user_reg(struct task_struct *task, int offset)
27 return task_pt_regs(task)->uregs[offset];
31 * this routine will put a word on the processes privileged stack.
32 * the offset is how far from the base addr as stored in the THREAD.
33 * this routine assumes that all the privileged stacks are in our
37 put_user_reg(struct task_struct *task, int offset, long data)
39 struct pt_regs newregs, *regs = task_pt_regs(task);
43 newregs.uregs[offset] = data;
45 if (valid_user_regs(&newregs)) {
46 regs->uregs[offset] = data;
54 * Called by kernel/ptrace.c when detaching..
56 void ptrace_disable(struct task_struct *child)
61 * We actually access the pt_regs stored on the kernel stack.
63 static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
64 unsigned long __user *ret)
69 if (off < sizeof(struct pt_regs))
70 tmp = get_user_reg(tsk, off >> 2);
72 return put_user(tmp, ret);
76 * We actually access the pt_regs stored on the kernel stack.
78 static int ptrace_write_user(struct task_struct *tsk, unsigned long off,
81 if (off >= sizeof(struct pt_regs))
84 return put_user_reg(tsk, off >> 2, val);
87 long arch_ptrace(struct task_struct *child, long request,
88 unsigned long addr, unsigned long data)
91 unsigned long __user *datap = (unsigned long __user *) data;
95 ret = ptrace_read_user(child, addr, datap);
99 ret = ptrace_write_user(child, addr, data);
102 case PTRACE_GET_THREAD_AREA:
103 ret = put_user(task_pt_regs(child)->UCreg_16,
108 ret = ptrace_request(child, request, addr, data);
115 asmlinkage int syscall_trace(int why, struct pt_regs *regs, int scno)
119 if (!test_thread_flag(TIF_SYSCALL_TRACE))
121 if (!(current->ptrace & PT_PTRACED))
125 * Save IP. IP is used to denote syscall entry/exit:
126 * IP = 0 -> entry, = 1 -> exit
129 regs->UCreg_ip = why;
131 current_thread_info()->syscall = scno;
133 /* the 0x80 provides a way for the tracing parent to distinguish
134 between a syscall stop and SIGTRAP delivery */
135 ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
138 * this isn't the same as continuing with a signal, but it will do
139 * for normal use. strace only continues with a signal if the
140 * stopping signal is not SIGTRAP. -brl
142 if (current->exit_code) {
143 send_sig(current->exit_code, current, 1);
144 current->exit_code = 0;
148 return current_thread_info()->syscall;