1 /*
2  *  linux/arch/h8300/kernel/ptrace.c
3  *
4  *  Yoshinori Sato <ysato@users.sourceforge.jp>
5  *
6  *  Based on:
7  *  linux/arch/m68k/kernel/ptrace.c
8  *
9  *  Copyright (C) 1994 by Hamish Macdonald
10  *  Taken from linux/kernel/ptrace.c and modified for M680x0.
11  *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
12  *
13  * This file is subject to the terms and conditions of the GNU General
14  * Public License.  See the file COPYING in the main directory of
15  * this archive for more details.
16  */
17 
18 #include <linux/kernel.h>
19 #include <linux/sched.h>
20 #include <linux/mm.h>
21 #include <linux/smp.h>
22 #include <linux/errno.h>
23 #include <linux/ptrace.h>
24 #include <linux/user.h>
25 #include <linux/signal.h>
26 
27 #include <asm/uaccess.h>
28 #include <asm/page.h>
29 #include <asm/pgtable.h>
30 #include <asm/system.h>
31 #include <asm/processor.h>
32 #include <asm/signal.h>
33 
34 /* cpu depend functions */
35 extern long h8300_get_reg(struct task_struct *task, int regno);
36 extern int  h8300_put_reg(struct task_struct *task, int regno, unsigned long data);
37 
38 
user_disable_single_step(struct task_struct * child)39 void user_disable_single_step(struct task_struct *child)
40 {
41 }
42 
43 /*
44  * does not yet catch signals sent when the child dies.
45  * in exit.c or in signal.c.
46  */
47 
ptrace_disable(struct task_struct * child)48 void ptrace_disable(struct task_struct *child)
49 {
50 	user_disable_single_step(child);
51 }
52 
arch_ptrace(struct task_struct * child,long request,unsigned long addr,unsigned long data)53 long arch_ptrace(struct task_struct *child, long request,
54 		 unsigned long addr, unsigned long data)
55 {
56 	int ret;
57 	int regno = addr >> 2;
58 	unsigned long __user *datap = (unsigned long __user *) data;
59 
60 	switch (request) {
61 	/* read the word at location addr in the USER area. */
62 		case PTRACE_PEEKUSR: {
63 			unsigned long tmp = 0;
64 
65 			if ((addr & 3) || addr >= sizeof(struct user)) {
66 				ret = -EIO;
67 				break ;
68 			}
69 
70 		        ret = 0;  /* Default return condition */
71 
72 			if (regno < H8300_REGS_NO)
73 				tmp = h8300_get_reg(child, regno);
74 			else {
75 				switch (regno) {
76 				case 49:
77 					tmp = child->mm->start_code;
78 					break ;
79 				case 50:
80 					tmp = child->mm->start_data;
81 					break ;
82 				case 51:
83 					tmp = child->mm->end_code;
84 					break ;
85 				case 52:
86 					tmp = child->mm->end_data;
87 					break ;
88 				default:
89 					ret = -EIO;
90 				}
91 			}
92 			if (!ret)
93 				ret = put_user(tmp, datap);
94 			break ;
95 		}
96 
97       /* when I and D space are separate, this will have to be fixed. */
98 		case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
99 			if ((addr & 3) || addr >= sizeof(struct user)) {
100 				ret = -EIO;
101 				break ;
102 			}
103 
104 			if (regno == PT_ORIG_ER0) {
105 				ret = -EIO;
106 				break ;
107 			}
108 			if (regno < H8300_REGS_NO) {
109 				ret = h8300_put_reg(child, regno, data);
110 				break ;
111 			}
112 			ret = -EIO;
113 			break ;
114 
115 		case PTRACE_GETREGS: { /* Get all gp regs from the child. */
116 		  	int i;
117 			unsigned long tmp;
118 			for (i = 0; i < H8300_REGS_NO; i++) {
119 			    tmp = h8300_get_reg(child, i);
120 			    if (put_user(tmp, datap)) {
121 				ret = -EFAULT;
122 				break;
123 			    }
124 			    datap++;
125 			}
126 			ret = 0;
127 			break;
128 		}
129 
130 		case PTRACE_SETREGS: { /* Set all gp regs in the child. */
131 			int i;
132 			unsigned long tmp;
133 			for (i = 0; i < H8300_REGS_NO; i++) {
134 			    if (get_user(tmp, datap)) {
135 				ret = -EFAULT;
136 				break;
137 			    }
138 			    h8300_put_reg(child, i, tmp);
139 			    datap++;
140 			}
141 			ret = 0;
142 			break;
143 		}
144 
145 		default:
146 			ret = ptrace_request(child, request, addr, data);
147 			break;
148 	}
149 	return ret;
150 }
151 
do_syscall_trace(void)152 asmlinkage void do_syscall_trace(void)
153 {
154 	if (!test_thread_flag(TIF_SYSCALL_TRACE))
155 		return;
156 	if (!(current->ptrace & PT_PTRACED))
157 		return;
158 	ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
159 				 ? 0x80 : 0));
160 	/*
161 	 * this isn't the same as continuing with a signal, but it will do
162 	 * for normal use.  strace only continues with a signal if the
163 	 * stopping signal is not SIGTRAP.  -brl
164 	 */
165 	if (current->exit_code) {
166 		send_sig(current->exit_code, current, 1);
167 		current->exit_code = 0;
168 	}
169 }
170