[linux-2.6-block.git] / arch / m68k / kernel / ptrace.c

/*
 *  linux/arch/m68k/kernel/ptrace.c
 *
 *  Copyright (C) 1994 by Hamish Macdonald
 *  Taken from linux/kernel/ptrace.c and modified for M680x0.
 *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
 *
 * This file is subject to the terms and conditions of the GNU General
 * Public License.  See the file COPYING in the main directory of
 * this archive for more details.
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/sched/task_stack.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/signal.h>
#include <linux/tracehook.h>

#include <linux/uaccess.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/processor.h>

/*
 * does not yet catch signals sent when the child dies.
 * in exit.c or in signal.c.
 */

/* determines which bits in the SR the user has access to. */
/* 1 = access 0 = no access */
#define SR_MASK 0x001f

/* sets the trace bits. */
#define TRACE_BITS 0xC000
#define T1_BIT 0x8000
#define T0_BIT 0x4000

/* Find the stack offset for a register, relative to thread.esp0. */
#define PT_REG(reg)	((long)&((struct pt_regs *)0)->reg)
#define SW_REG(reg)	((long)&((struct switch_stack *)0)->reg \
			 - sizeof(struct switch_stack))
/* Mapping from PT_xxx to the stack offset at which the register is
   saved.  Notice that usp has no stack-slot and needs to be treated
   specially (see get_reg/put_reg below). */
static const int regoff[] = {
	[0]	= PT_REG(d1),
	[1]	= PT_REG(d2),
	[2]	= PT_REG(d3),
	[3]	= PT_REG(d4),
	[4]	= PT_REG(d5),
	[5]	= SW_REG(d6),
	[6]	= SW_REG(d7),
	[7]	= PT_REG(a0),
	[8]	= PT_REG(a1),
	[9]	= PT_REG(a2),
	[10]	= SW_REG(a3),
	[11]	= SW_REG(a4),
	[12]	= SW_REG(a5),
	[13]	= SW_REG(a6),
	[14]	= PT_REG(d0),
	[15]	= -1,
	[16]	= PT_REG(orig_d0),
	[17]	= PT_REG(sr),
	[18]	= PT_REG(pc),
};

/*
 * Get contents of register REGNO in task TASK.
 */
static inline long get_reg(struct task_struct *task, int regno)
{
	unsigned long *addr;

	if (regno == PT_USP)
		addr = &task->thread.usp;
	else if (regno < ARRAY_SIZE(regoff))
		addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
	else
		return 0;
	/* Need to take stkadj into account. */
	if (regno == PT_SR || regno == PT_PC) {
		long stkadj = *(long *)(task->thread.esp0 + PT_REG(stkadj));
		addr = (unsigned long *) ((unsigned long)addr + stkadj);
		/* The sr is actually a 16 bit register.  */
		if (regno == PT_SR)
			return *(unsigned short *)addr;
	}
	return *addr;
}

/*
 * Write contents of register REGNO in task TASK.
 */
static inline int put_reg(struct task_struct *task, int regno,
			  unsigned long data)
{
	unsigned long *addr;

	if (regno == PT_USP)
		addr = &task->thread.usp;
	else if (regno < ARRAY_SIZE(regoff))
		addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
	else
		return -1;
	/* Need to take stkadj into account. */
	if (regno == PT_SR || regno == PT_PC) {
		long stkadj = *(long *)(task->thread.esp0 + PT_REG(stkadj));
		addr = (unsigned long *) ((unsigned long)addr + stkadj);
		/* The sr is actually a 16 bit register.  */
		if (regno == PT_SR) {
			*(unsigned short *)addr = data;
			return 0;
		}
	}
	*addr = data;
	return 0;
}

/*
 * Make sure the single step bit is not set.
 */
static inline void singlestep_disable(struct task_struct *child)
{
	unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS;
	put_reg(child, PT_SR, tmp);
	clear_tsk_thread_flag(child, TIF_DELAYED_TRACE);
}

/*
 * Called by kernel/ptrace.c when detaching..
 */
void ptrace_disable(struct task_struct *child)
{
	singlestep_disable(child);
}

void user_enable_single_step(struct task_struct *child)
{
	unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS;
	put_reg(child, PT_SR, tmp | T1_BIT);
	set_tsk_thread_flag(child, TIF_DELAYED_TRACE);
}

#ifdef CONFIG_MMU
void user_enable_block_step(struct task_struct *child)
{
	unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS;
	put_reg(child, PT_SR, tmp | T0_BIT);
}
#endif

void user_disable_single_step(struct task_struct *child)
{
	singlestep_disable(child);
}

long arch_ptrace(struct task_struct *child, long request,
		 unsigned long addr, unsigned long data)
{
	unsigned long tmp;
	int i, ret = 0;
	int regno = addr >> 2; /* temporary hack. */
	unsigned long __user *datap = (unsigned long __user *) data;

	switch (request) {
	/* read the word at location addr in the USER area. */
	case PTRACE_PEEKUSR:
		if (addr & 3)
			goto out_eio;

		if (regno >= 0 && regno < 19) {
			tmp = get_reg(child, regno);
		} else if (regno >= 21 && regno < 49) {
			tmp = child->thread.fp[regno - 21];
			/* Convert internal fpu reg representation
			 * into long double format
			 */
			if (FPU_IS_EMU && (regno < 45) && !(regno % 3))
				tmp = ((tmp & 0xffff0000) << 15) |
				      ((tmp & 0x0000ffff) << 16);
#ifndef CONFIG_MMU
		} else if (regno == 49) {
			tmp = child->mm->start_code;
		} else if (regno == 50) {
			tmp = child->mm->start_data;
		} else if (regno == 51) {
			tmp = child->mm->end_code;
#endif
		} else
			goto out_eio;
		ret = put_user(tmp, datap);
		break;

	case PTRACE_POKEUSR:
	/* write the word at location addr in the USER area */
		if (addr & 3)
			goto out_eio;

		if (regno == PT_SR) {
			data &= SR_MASK;
			data |= get_reg(child, PT_SR) & ~SR_MASK;
		}
		if (regno >= 0 && regno < 19) {
			if (put_reg(child, regno, data))
				goto out_eio;
		} else if (regno >= 21 && regno < 48) {
			/* Convert long double format
			 * into internal fpu reg representation
			 */
			if (FPU_IS_EMU && (regno < 45) && !(regno % 3)) {
				data <<= 15;
				data = (data & 0xffff0000) |
				       ((data & 0x0000ffff) >> 1);
			}
			child->thread.fp[regno - 21] = data;
		} else
			goto out_eio;
		break;

	case PTRACE_GETREGS:	/* Get all gp regs from the child. */
		for (i = 0; i < 19; i++) {
			tmp = get_reg(child, i);
			ret = put_user(tmp, datap);
			if (ret)
				break;
			datap++;
		}
		break;

	case PTRACE_SETREGS:	/* Set all gp regs in the child. */
		for (i = 0; i < 19; i++) {
			ret = get_user(tmp, datap);
			if (ret)
				break;
			if (i == PT_SR) {
				tmp &= SR_MASK;
				tmp |= get_reg(child, PT_SR) & ~SR_MASK;
			}
			put_reg(child, i, tmp);
			datap++;
		}
		break;

	case PTRACE_GETFPREGS:	/* Get the child FPU state. */
		if (copy_to_user(datap, &child->thread.fp,
				 sizeof(struct user_m68kfp_struct)))
			ret = -EFAULT;
		break;

	case PTRACE_SETFPREGS:	/* Set the child FPU state. */
		if (copy_from_user(&child->thread.fp, datap,
				   sizeof(struct user_m68kfp_struct)))
			ret = -EFAULT;
		break;

	case PTRACE_GET_THREAD_AREA:
		ret = put_user(task_thread_info(child)->tp_value, datap);
		break;

	default:
		ret = ptrace_request(child, request, addr, data);
		break;
	}

	return ret;
out_eio:
	return -EIO;
}

asmlinkage void syscall_trace(void)
{
	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;
	}
}

#if defined(CONFIG_COLDFIRE) || !defined(CONFIG_MMU)
asmlinkage int syscall_trace_enter(void)
{
	int ret = 0;

	if (test_thread_flag(TIF_SYSCALL_TRACE))
		ret = tracehook_report_syscall_entry(task_pt_regs(current));
	return ret;
}

asmlinkage void syscall_trace_leave(void)
{
	if (test_thread_flag(TIF_SYSCALL_TRACE))
		tracehook_report_syscall_exit(task_pt_regs(current), 0);
}
#endif /* CONFIG_COLDFIRE */
Commit	Line	Data
43dec91f GU	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>
68db0cf1	15	#include <linux/sched/task_stack.h>
43dec91f GU	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
7c0f6ba6	24	#include <linux/uaccess.h>
43dec91f GU	25	#include <asm/page.h>
43dec91f GU	26	#include <asm/pgtable.h>
43dec91f GU	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). */
	50	static 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	*/
	75	static 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	*/
99	static 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	*/
127	static 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	*/
137	void ptrace_disable(struct task_struct *child)
138	{
139	singlestep_disable(child);
140	}
141
142	void 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
66d857b0	149	#ifdef CONFIG_MMU
43dec91f GU	150	void 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	}
66d857b0	155	#endif
43dec91f GU	156
	157	void user_disable_single_step(struct task_struct *child)
	158	{
	159	singlestep_disable(child);
	160	}
	161
	162	long 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;
271	out_eio:
272	return -EIO;
273	}
274
275	asmlinkage 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
70c778f7	290	#if defined(CONFIG_COLDFIRE) \|\| !defined(CONFIG_MMU)
43dec91f GU	291	asmlinkage 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
	300	asmlinkage 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 */