[net-next-2.6.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/mm.h>
#include <linux/smp.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/signal.h>

#include <asm/uaccess.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/system.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);
}

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);
}

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;

	switch (request) {
	/* read the word at location addr in the USER area. */
	case PTRACE_PEEKUSR:
		if (addr & 3)
			goto out_eio;
		addr >>= 2;	/* temporary hack. */

		if (addr >= 0 && addr < 19) {
			tmp = get_reg(child, addr);
		} else if (addr >= 21 && addr < 49) {
			tmp = child->thread.fp[addr - 21];
			/* Convert internal fpu reg representation
			 * into long double format
			 */
			if (FPU_IS_EMU && (addr < 45) && !(addr % 3))
				tmp = ((tmp & 0xffff0000) << 15) |
				      ((tmp & 0x0000ffff) << 16);
		} else
			goto out_eio;
		ret = put_user(tmp, (unsigned long *)data);
		break;

	case PTRACE_POKEUSR:	/* write the word at location addr in the USER area */
		if (addr & 3)
			goto out_eio;
		addr >>= 2;	/* temporary hack. */

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

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

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

	case PTRACE_GET_THREAD_AREA:
		ret = put_user(task_thread_info(child)->tp_value,
			       (unsigned long __user *)data);
		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;
	}
}
Commit	Line	Data
1da177e4 LT	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/mm.h>
	16	#include <linux/smp.h>
1da177e4 LT	17	#include <linux/errno.h>
	18	#include <linux/ptrace.h>
	19	#include <linux/user.h>
7ed20e1a	20	#include <linux/signal.h>
1da177e4 LT	21
	22	#include <asm/uaccess.h>
	23	#include <asm/page.h>
	24	#include <asm/pgtable.h>
	25	#include <asm/system.h>
	26	#include <asm/processor.h>
	27
	28	/*
	29	* does not yet catch signals sent when the child dies.
	30	* in exit.c or in signal.c.
	31	*/
	32
	33	/* determines which bits in the SR the user has access to. */
	34	/* 1 = access 0 = no access */
	35	#define SR_MASK 0x001f
	36
	37	/* sets the trace bits. */
faa47b46 AS	38	#define TRACE_BITS 0xC000
	39	#define T1_BIT 0x8000
	40	#define T0_BIT 0x4000
1da177e4 LT	41
	42	/* Find the stack offset for a register, relative to thread.esp0. */
	43	#define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg)
	44	#define SW_REG(reg) ((long)&((struct switch_stack *)0)->reg \
	45	- sizeof(struct switch_stack))
	46	/* Mapping from PT_xxx to the stack offset at which the register is
	47	saved. Notice that usp has no stack-slot and needs to be treated
	48	specially (see get_reg/put_reg below). */
f195e2bf	49	static const int regoff[] = {
1da177e4 LT	50	[0] = PT_REG(d1),
	51	[1] = PT_REG(d2),
	52	[2] = PT_REG(d3),
	53	[3] = PT_REG(d4),
	54	[4] = PT_REG(d5),
	55	[5] = SW_REG(d6),
	56	[6] = SW_REG(d7),
	57	[7] = PT_REG(a0),
	58	[8] = PT_REG(a1),
	59	[9] = PT_REG(a2),
	60	[10] = SW_REG(a3),
	61	[11] = SW_REG(a4),
	62	[12] = SW_REG(a5),
	63	[13] = SW_REG(a6),
	64	[14] = PT_REG(d0),
	65	[15] = -1,
	66	[16] = PT_REG(orig_d0),
	67	[17] = PT_REG(sr),
	68	[18] = PT_REG(pc),
	69	};
	70
	71	/*
	72	* Get contents of register REGNO in task TASK.
	73	*/
	74	static inline long get_reg(struct task_struct *task, int regno)
	75	{
	76	unsigned long *addr;
	77
	78	if (regno == PT_USP)
	79	addr = &task->thread.usp;
ea5e1a82	80	else if (regno < ARRAY_SIZE(regoff))
1da177e4 LT	81	addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
	82	else
	83	return 0;
f195e2bf AS	84	/* Need to take stkadj into account. */
	85	if (regno == PT_SR \|\| regno == PT_PC) {
	86	long stkadj = (long )(task->thread.esp0 + PT_REG(stkadj));
	87	addr = (unsigned long *) ((unsigned long)addr + stkadj);
	88	/* The sr is actually a 16 bit register. */
	89	if (regno == PT_SR)
	90	return (unsigned short )addr;
	91	}
1da177e4 LT	92	return *addr;
	93	}
	94
	95	/*
	96	* Write contents of register REGNO in task TASK.
	97	*/
	98	static inline int put_reg(struct task_struct *task, int regno,
	99	unsigned long data)
	100	{
	101	unsigned long *addr;
	102
	103	if (regno == PT_USP)
	104	addr = &task->thread.usp;
ea5e1a82	105	else if (regno < ARRAY_SIZE(regoff))
b3319f50	106	addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
1da177e4 LT	107	else
1da177e4 LT	108	return -1;
f195e2bf AS	109	/* Need to take stkadj into account. */
	110	if (regno == PT_SR \|\| regno == PT_PC) {
	111	long stkadj = (long )(task->thread.esp0 + PT_REG(stkadj));
	112	addr = (unsigned long *) ((unsigned long)addr + stkadj);
	113	/* The sr is actually a 16 bit register. */
	114	if (regno == PT_SR) {
	115	(unsigned short )addr = data;
	116	return 0;
	117	}
	118	}
1da177e4 LT	119	*addr = data;
	120	return 0;
	121	}
	122
	123	/*
1da177e4 LT	124	* Make sure the single step bit is not set.
1da177e4 LT	125	*/
69f447cf	126	static inline void singlestep_disable(struct task_struct *child)
1da177e4	127	{
f195e2bf	128	unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS;
1da177e4	129	put_reg(child, PT_SR, tmp);
3b66a1ed	130	clear_tsk_thread_flag(child, TIF_DELAYED_TRACE);
69f447cf RZ	131	}
	132
	133	/*
	134	* Called by kernel/ptrace.c when detaching..
	135	*/
	136	void ptrace_disable(struct task_struct *child)
	137	{
	138	singlestep_disable(child);
1da177e4 LT	139	}
1da177e4 LT	140
faa47b46 AS	141	void user_enable_single_step(struct task_struct *child)
faa47b46 AS	142	{
f195e2bf AS	143	unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS;
f195e2bf AS	144	put_reg(child, PT_SR, tmp \| T1_BIT);
faa47b46 AS	145	set_tsk_thread_flag(child, TIF_DELAYED_TRACE);
	146	}
	147
	148	void user_enable_block_step(struct task_struct *child)
	149	{
f195e2bf AS	150	unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS;
f195e2bf AS	151	put_reg(child, PT_SR, tmp \| T0_BIT);
faa47b46 AS	152	}
	153
	154	void user_disable_single_step(struct task_struct *child)
	155	{
	156	singlestep_disable(child);
	157	}
	158
9b05a69e NK	159	long arch_ptrace(struct task_struct *child, long request,
9b05a69e NK	160	unsigned long addr, unsigned long data)
1da177e4	161	{
69f447cf RZ	162	unsigned long tmp;
69f447cf RZ	163	int i, ret = 0;
1da177e4	164
1da177e4	165	switch (request) {
1da177e4	166	/* read the word at location addr in the USER area. */
69f447cf RZ	167	case PTRACE_PEEKUSR:
	168	if (addr & 3)
	169	goto out_eio;
	170	addr >>= 2; /* temporary hack. */
1da177e4	171
69f447cf	172	if (addr >= 0 && addr < 19) {
b3319f50	173	tmp = get_reg(child, addr);
b3319f50 RZ	174	} else if (addr >= 21 && addr < 49) {
b3319f50 RZ	175	tmp = child->thread.fp[addr - 21];
b3319f50 RZ	176	/* Convert internal fpu reg representation
	177	* into long double format
	178	*/
	179	if (FPU_IS_EMU && (addr < 45) && !(addr % 3))
	180	tmp = ((tmp & 0xffff0000) << 15) \|
	181	((tmp & 0x0000ffff) << 16);
b3319f50	182	} else
f195e2bf	183	goto out_eio;
b3319f50 RZ	184	ret = put_user(tmp, (unsigned long *)data);
b3319f50 RZ	185	break;
1da177e4	186
b3319f50	187	case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
69f447cf RZ	188	if (addr & 3)
	189	goto out_eio;
	190	addr >>= 2; /* temporary hack. */
1da177e4	191
b3319f50 RZ	192	if (addr == PT_SR) {
b3319f50 RZ	193	data &= SR_MASK;
f195e2bf AS	194	data \|= get_reg(child, PT_SR) & ~SR_MASK;
	195	}
	196	if (addr >= 0 && addr < 19) {
b3319f50	197	if (put_reg(child, addr, data))
69f447cf RZ	198	goto out_eio;
69f447cf RZ	199	} else if (addr >= 21 && addr < 48) {
b3319f50 RZ	200	/* Convert long double format
	201	* into internal fpu reg representation
	202	*/
	203	if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) {
9b05a69e	204	data <<= 15;
b3319f50 RZ	205	data = (data & 0xffff0000) \|
	206	((data & 0x0000ffff) >> 1);
	207	}
b3319f50	208	child->thread.fp[addr - 21] = data;
69f447cf RZ	209	} else
69f447cf RZ	210	goto out_eio;
b3319f50	211	break;
1da177e4	212
69f447cf	213	case PTRACE_GETREGS: /* Get all gp regs from the child. */
b3319f50 RZ	214	for (i = 0; i < 19; i++) {
b3319f50 RZ	215	tmp = get_reg(child, i);
69f447cf RZ	216	ret = put_user(tmp, (unsigned long *)data);
69f447cf RZ	217	if (ret)
1da177e4	218	break;
9b05a69e	219	data += sizeof(unsigned long);
1da177e4	220	}
b3319f50	221	break;
1da177e4	222
69f447cf	223	case PTRACE_SETREGS: /* Set all gp regs in the child. */
b3319f50	224	for (i = 0; i < 19; i++) {
69f447cf RZ	225	ret = get_user(tmp, (unsigned long *)data);
69f447cf RZ	226	if (ret)
1da177e4	227	break;
b3319f50	228	if (i == PT_SR) {
1da177e4	229	tmp &= SR_MASK;
f195e2bf	230	tmp \|= get_reg(child, PT_SR) & ~SR_MASK;
1da177e4	231	}
b3319f50	232	put_reg(child, i, tmp);
9b05a69e	233	data += sizeof(unsigned long);
1da177e4	234	}
b3319f50	235	break;
1da177e4	236
69f447cf	237	case PTRACE_GETFPREGS: /* Get the child FPU state. */
b3319f50 RZ	238	if (copy_to_user((void *)data, &child->thread.fp,
	239	sizeof(struct user_m68kfp_struct)))
	240	ret = -EFAULT;
	241	break;
1da177e4	242
69f447cf	243	case PTRACE_SETFPREGS: /* Set the child FPU state. */
b3319f50 RZ	244	if (copy_from_user(&child->thread.fp, (void *)data,
	245	sizeof(struct user_m68kfp_struct)))
	246	ret = -EFAULT;
	247	break;
1da177e4	248
9674cdc7 MK	249	case PTRACE_GET_THREAD_AREA:
	250	ret = put_user(task_thread_info(child)->tp_value,
	251	(unsigned long __user *)data);
	252	break;
	253
b3319f50 RZ	254	default:
	255	ret = ptrace_request(child, request, addr, data);
	256	break;
1da177e4	257	}
481bed45	258
1da177e4	259	return ret;
69f447cf	260	out_eio:
481bed45	261	return -EIO;
1da177e4 LT	262	}
	263
	264	asmlinkage void syscall_trace(void)
	265	{
1da177e4 LT	266	ptrace_notify(SIGTRAP \| ((current->ptrace & PT_TRACESYSGOOD)
	267	? 0x80 : 0));
	268	/*
	269	* this isn't the same as continuing with a signal, but it will do
	270	* for normal use. strace only continues with a signal if the
	271	* stopping signal is not SIGTRAP. -brl
	272	*/
	273	if (current->exit_code) {
	274	send_sig(current->exit_code, current, 1);
	275	current->exit_code = 0;
	276	}
	277	}