1#ifdef CONFIG_MMU
2#include "ptrace_mm.c"
3#else
4#include "ptrace_no.c"
 
 
5#endif

  1/*
  2 *  linux/arch/m68k/kernel/ptrace.c
  3 *
  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
  7 *
  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.
 11 */
 12
 13#include <linux/kernel.h>
 14#include <linux/sched.h>
 15#include <linux/sched/task_stack.h>
 16#include <linux/mm.h>
 17#include <linux/smp.h>
 18#include <linux/errno.h>
 19#include <linux/ptrace.h>
 20#include <linux/user.h>
 21#include <linux/signal.h>
 22#include <linux/tracehook.h>
 23
 24#include <linux/uaccess.h>
 25#include <asm/page.h>
 26#include <asm/pgtable.h>
 27#include <asm/processor.h>
 28
 29/*
 30 * does not yet catch signals sent when the child dies.
 31 * in exit.c or in signal.c.
 32 */
 33
 34/* determines which bits in the SR the user has access to. */
 35/* 1 = access 0 = no access */
 36#define SR_MASK 0x001f
 37
 38/* sets the trace bits. */
 39#define TRACE_BITS 0xC000
 40#define T1_BIT 0x8000
 41#define T0_BIT 0x4000
 42
 43/* Find the stack offset for a register, relative to thread.esp0. */
 44#define PT_REG(reg)	((long)&((struct pt_regs *)0)->reg)
 45#define SW_REG(reg)	((long)&((struct switch_stack *)0)->reg \
 46			 - sizeof(struct switch_stack))
 47/* Mapping from PT_xxx to the stack offset at which the register is
 48   saved.  Notice that usp has no stack-slot and needs to be treated
 49   specially (see get_reg/put_reg below). */
 50static const int regoff[] = {
 51	[0]	= PT_REG(d1),
 52	[1]	= PT_REG(d2),
 53	[2]	= PT_REG(d3),
 54	[3]	= PT_REG(d4),
 55	[4]	= PT_REG(d5),
 56	[5]	= SW_REG(d6),
 57	[6]	= SW_REG(d7),
 58	[7]	= PT_REG(a0),
 59	[8]	= PT_REG(a1),
 60	[9]	= PT_REG(a2),
 61	[10]	= SW_REG(a3),
 62	[11]	= SW_REG(a4),
 63	[12]	= SW_REG(a5),
 64	[13]	= SW_REG(a6),
 65	[14]	= PT_REG(d0),
 66	[15]	= -1,
 67	[16]	= PT_REG(orig_d0),
 68	[17]	= PT_REG(sr),
 69	[18]	= PT_REG(pc),
 70};
 71
 72/*
 73 * Get contents of register REGNO in task TASK.
 74 */
 75static inline long get_reg(struct task_struct *task, int regno)
 76{
 77	unsigned long *addr;
 78
 79	if (regno == PT_USP)
 80		addr = &task->thread.usp;
 81	else if (regno < ARRAY_SIZE(regoff))
 82		addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
 83	else
 84		return 0;
 85	/* Need to take stkadj into account. */
 86	if (regno == PT_SR || regno == PT_PC) {
 87		long stkadj = *(long *)(task->thread.esp0 + PT_REG(stkadj));
 88		addr = (unsigned long *) ((unsigned long)addr + stkadj);
 89		/* The sr is actually a 16 bit register.  */
 90		if (regno == PT_SR)
 91			return *(unsigned short *)addr;
 92	}
 93	return *addr;
 94}
 95
 96/*
 97 * Write contents of register REGNO in task TASK.
 98 */
 99static inline int put_reg(struct task_struct *task, int regno,
100			  unsigned long data)
101{
102	unsigned long *addr;
103
104	if (regno == PT_USP)
105		addr = &task->thread.usp;
106	else if (regno < ARRAY_SIZE(regoff))
107		addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
108	else
109		return -1;
110	/* Need to take stkadj into account. */
111	if (regno == PT_SR || regno == PT_PC) {
112		long stkadj = *(long *)(task->thread.esp0 + PT_REG(stkadj));
113		addr = (unsigned long *) ((unsigned long)addr + stkadj);
114		/* The sr is actually a 16 bit register.  */
115		if (regno == PT_SR) {
116			*(unsigned short *)addr = data;
117			return 0;
118		}
119	}
120	*addr = data;
121	return 0;
122}
123
124/*
125 * Make sure the single step bit is not set.
126 */
127static inline void singlestep_disable(struct task_struct *child)
128{
129	unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS;
130	put_reg(child, PT_SR, tmp);
131	clear_tsk_thread_flag(child, TIF_DELAYED_TRACE);
132}
133
134/*
135 * Called by kernel/ptrace.c when detaching..
136 */
137void ptrace_disable(struct task_struct *child)
138{
139	singlestep_disable(child);
140}
141
142void user_enable_single_step(struct task_struct *child)
143{
144	unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS;
145	put_reg(child, PT_SR, tmp | T1_BIT);
146	set_tsk_thread_flag(child, TIF_DELAYED_TRACE);
147}
148
149#ifdef CONFIG_MMU
150void user_enable_block_step(struct task_struct *child)
151{
152	unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS;
153	put_reg(child, PT_SR, tmp | T0_BIT);
154}
155#endif
156
157void user_disable_single_step(struct task_struct *child)
158{
159	singlestep_disable(child);
160}
161
162long arch_ptrace(struct task_struct *child, long request,
163		 unsigned long addr, unsigned long data)
164{
165	unsigned long tmp;
166	int i, ret = 0;
167	int regno = addr >> 2; /* temporary hack. */
168	unsigned long __user *datap = (unsigned long __user *) data;
169
170	switch (request) {
171	/* read the word at location addr in the USER area. */
172	case PTRACE_PEEKUSR:
173		if (addr & 3)
174			goto out_eio;
175
176		if (regno >= 0 && regno < 19) {
177			tmp = get_reg(child, regno);
178		} else if (regno >= 21 && regno < 49) {
179			tmp = child->thread.fp[regno - 21];
180			/* Convert internal fpu reg representation
181			 * into long double format
182			 */
183			if (FPU_IS_EMU && (regno < 45) && !(regno % 3))
184				tmp = ((tmp & 0xffff0000) << 15) |
185				      ((tmp & 0x0000ffff) << 16);
186#ifndef CONFIG_MMU
187		} else if (regno == 49) {
188			tmp = child->mm->start_code;
189		} else if (regno == 50) {
190			tmp = child->mm->start_data;
191		} else if (regno == 51) {
192			tmp = child->mm->end_code;
193#endif
194		} else
195			goto out_eio;
196		ret = put_user(tmp, datap);
197		break;
198
199	case PTRACE_POKEUSR:
200	/* write the word at location addr in the USER area */
201		if (addr & 3)
202			goto out_eio;
203
204		if (regno == PT_SR) {
205			data &= SR_MASK;
206			data |= get_reg(child, PT_SR) & ~SR_MASK;
207		}
208		if (regno >= 0 && regno < 19) {
209			if (put_reg(child, regno, data))
210				goto out_eio;
211		} else if (regno >= 21 && regno < 48) {
212			/* Convert long double format
213			 * into internal fpu reg representation
214			 */
215			if (FPU_IS_EMU && (regno < 45) && !(regno % 3)) {
216				data <<= 15;
217				data = (data & 0xffff0000) |
218				       ((data & 0x0000ffff) >> 1);
219			}
220			child->thread.fp[regno - 21] = data;
221		} else
222			goto out_eio;
223		break;
224
225	case PTRACE_GETREGS:	/* Get all gp regs from the child. */
226		for (i = 0; i < 19; i++) {
227			tmp = get_reg(child, i);
228			ret = put_user(tmp, datap);
229			if (ret)
230				break;
231			datap++;
232		}
233		break;
234
235	case PTRACE_SETREGS:	/* Set all gp regs in the child. */
236		for (i = 0; i < 19; i++) {
237			ret = get_user(tmp, datap);
238			if (ret)
239				break;
240			if (i == PT_SR) {
241				tmp &= SR_MASK;
242				tmp |= get_reg(child, PT_SR) & ~SR_MASK;
243			}
244			put_reg(child, i, tmp);
245			datap++;
246		}
247		break;
248
249	case PTRACE_GETFPREGS:	/* Get the child FPU state. */
250		if (copy_to_user(datap, &child->thread.fp,
251				 sizeof(struct user_m68kfp_struct)))
252			ret = -EFAULT;
253		break;
254
255	case PTRACE_SETFPREGS:	/* Set the child FPU state. */
256		if (copy_from_user(&child->thread.fp, datap,
257				   sizeof(struct user_m68kfp_struct)))
258			ret = -EFAULT;
259		break;
260
261	case PTRACE_GET_THREAD_AREA:
262		ret = put_user(task_thread_info(child)->tp_value, datap);
263		break;
264
265	default:
266		ret = ptrace_request(child, request, addr, data);
267		break;
268	}
269
270	return ret;
271out_eio:
272	return -EIO;
273}
274
275asmlinkage void syscall_trace(void)
276{
277	ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
278				 ? 0x80 : 0));
279	/*
280	 * this isn't the same as continuing with a signal, but it will do
281	 * for normal use.  strace only continues with a signal if the
282	 * stopping signal is not SIGTRAP.  -brl
283	 */
284	if (current->exit_code) {
285		send_sig(current->exit_code, current, 1);
286		current->exit_code = 0;
287	}
288}
289
290#if defined(CONFIG_COLDFIRE) || !defined(CONFIG_MMU)
291asmlinkage int syscall_trace_enter(void)
292{
293	int ret = 0;
294
295	if (test_thread_flag(TIF_SYSCALL_TRACE))
296		ret = tracehook_report_syscall_entry(task_pt_regs(current));
297	return ret;
298}
299
300asmlinkage void syscall_trace_leave(void)
301{
302	if (test_thread_flag(TIF_SYSCALL_TRACE))
303		tracehook_report_syscall_exit(task_pt_regs(current), 0);
304}
305#endif /* CONFIG_COLDFIRE */