2 * linux/arch/m68knommu/kernel/ptrace.c
4 * Copyright (C) 1994 by Hamish Macdonald
5 * Taken from linux/kernel/ptrace.c and modified for M680x0.
6 * linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
8 * This file is subject to the terms and conditions of the GNU General
9 * Public License. See the file COPYING in the main directory of
10 * this archive for more details.
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
16 #include <linux/smp.h>
17 #include <linux/errno.h>
18 #include <linux/ptrace.h>
19 #include <linux/user.h>
20 #include <linux/signal.h>
22 #include <asm/uaccess.h>
24 #include <asm/pgtable.h>
25 #include <asm/system.h>
26 #include <asm/processor.h>
29 * does not yet catch signals sent when the child dies.
30 * in exit.c or in signal.c.
33 /* determines which bits in the SR the user has access to. */
34 /* 1 = access 0 = no access */
35 #define SR_MASK 0x001f
37 /* sets the trace bits. */
38 #define TRACE_BITS 0x8000
40 /* Find the stack offset for a register, relative to thread.esp0. */
41 #define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg)
42 #define SW_REG(reg) ((long)&((struct switch_stack *)0)->reg \
43 - sizeof(struct switch_stack))
44 /* Mapping from PT_xxx to the stack offset at which the register is
45 saved. Notice that usp has no stack-slot and needs to be treated
46 specially (see get_reg/put_reg below). */
47 static int regoff[] = {
48 PT_REG(d1), PT_REG(d2), PT_REG(d3), PT_REG(d4),
49 PT_REG(d5), SW_REG(d6), SW_REG(d7), PT_REG(a0),
50 PT_REG(a1), PT_REG(a2), SW_REG(a3), SW_REG(a4),
51 SW_REG(a5), SW_REG(a6), PT_REG(d0), -1,
52 PT_REG(orig_d0), PT_REG(sr), PT_REG(pc),
56 * Get contents of register REGNO in task TASK.
58 static inline long get_reg(struct task_struct *task, int regno)
63 addr = &task->thread.usp;
64 else if (regno < ARRAY_SIZE(regoff))
65 addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
72 * Write contents of register REGNO in task TASK.
74 static inline int put_reg(struct task_struct *task, int regno,
80 addr = &task->thread.usp;
81 else if (regno < ARRAY_SIZE(regoff))
82 addr = (unsigned long *) (task->thread.esp0 + regoff[regno]);
89 void user_enable_single_step(struct task_struct *task)
91 unsigned long srflags;
92 srflags = get_reg(task, PT_SR) | (TRACE_BITS << 16);
93 put_reg(task, PT_SR, srflags);
96 void user_disable_single_step(struct task_struct *task)
98 unsigned long srflags;
99 srflags = get_reg(task, PT_SR) & ~(TRACE_BITS << 16);
100 put_reg(task, PT_SR, srflags);
104 * Called by kernel/ptrace.c when detaching..
106 * Make sure the single step bit is not set.
108 void ptrace_disable(struct task_struct *child)
110 /* make sure the single step bit is not set. */
111 user_disable_single_step(child);
114 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
119 /* read the word at location addr in the USER area. */
120 case PTRACE_PEEKUSR: {
124 if ((addr & 3) || addr < 0 ||
125 addr > sizeof(struct user) - 3)
128 tmp = 0; /* Default return condition */
129 addr = addr >> 2; /* temporary hack. */
132 tmp = get_reg(child, addr);
135 } else if (addr >= 21 && addr < 49) {
136 tmp = child->thread.fp[addr - 21];
137 #ifdef CONFIG_M68KFPU_EMU
138 /* Convert internal fpu reg representation
139 * into long double format
141 if (FPU_IS_EMU && (addr < 45) && !(addr % 3))
142 tmp = ((tmp & 0xffff0000) << 15) |
143 ((tmp & 0x0000ffff) << 16);
145 } else if (addr == 49) {
146 tmp = child->mm->start_code;
147 } else if (addr == 50) {
148 tmp = child->mm->start_data;
149 } else if (addr == 51) {
150 tmp = child->mm->end_code;
153 ret = put_user(tmp,(unsigned long *) data);
157 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
159 if ((addr & 3) || addr < 0 ||
160 addr > sizeof(struct user) - 3)
163 addr = addr >> 2; /* temporary hack. */
168 data |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
171 if (put_reg(child, addr, data))
176 if (addr >= 21 && addr < 48)
178 #ifdef CONFIG_M68KFPU_EMU
179 /* Convert long double format
180 * into internal fpu reg representation
182 if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) {
183 data = (unsigned long)data << 15;
184 data = (data & 0xffff0000) |
185 ((data & 0x0000ffff) >> 1);
188 child->thread.fp[addr - 21] = data;
193 case PTRACE_GETREGS: { /* Get all gp regs from the child. */
196 for (i = 0; i < 19; i++) {
197 tmp = get_reg(child, i);
200 if (put_user(tmp, (unsigned long *) data)) {
204 data += sizeof(long);
210 case PTRACE_SETREGS: { /* Set all gp regs in the child. */
213 for (i = 0; i < 19; i++) {
214 if (get_user(tmp, (unsigned long *) data)) {
221 tmp |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
223 put_reg(child, i, tmp);
224 data += sizeof(long);
230 #ifdef PTRACE_GETFPREGS
231 case PTRACE_GETFPREGS: { /* Get the child FPU state. */
233 if (copy_to_user((void *)data, &child->thread.fp,
234 sizeof(struct user_m68kfp_struct)))
240 #ifdef PTRACE_SETFPREGS
241 case PTRACE_SETFPREGS: { /* Set the child FPU state. */
243 if (copy_from_user(&child->thread.fp, (void *)data,
244 sizeof(struct user_m68kfp_struct)))
250 case PTRACE_GET_THREAD_AREA:
251 ret = put_user(task_thread_info(child)->tp_value,
252 (unsigned long __user *)data);
256 ret = ptrace_request(child, request, addr, data);
262 asmlinkage void syscall_trace(void)
264 if (!test_thread_flag(TIF_SYSCALL_TRACE))
266 if (!(current->ptrace & PT_PTRACED))
268 ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
271 * this isn't the same as continuing with a signal, but it will do
272 * for normal use. strace only continues with a signal if the
273 * stopping signal is not SIGTRAP. -brl
275 if (current->exit_code) {
276 send_sig(current->exit_code, current, 1);
277 current->exit_code = 0;