[linux-2.6-block.git] / arch / m68knommu / kernel / ptrace.c

/*
 *  linux/arch/m68knommu/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 0x8000

/* 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 int regoff[] = {
	PT_REG(d1), PT_REG(d2), PT_REG(d3), PT_REG(d4),
	PT_REG(d5), SW_REG(d6), SW_REG(d7), PT_REG(a0),
	PT_REG(a1), PT_REG(a2), SW_REG(a3), SW_REG(a4),
	SW_REG(a5), SW_REG(a6), PT_REG(d0), -1,
	PT_REG(orig_d0), PT_REG(sr), 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;
	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;
	*addr = data;
	return 0;
}

void user_enable_single_step(struct task_struct *task)
{
	unsigned long srflags;
	srflags = get_reg(task, PT_SR) | (TRACE_BITS << 16);
	put_reg(task, PT_SR, srflags);
}

void user_disable_single_step(struct task_struct *task)
{
	unsigned long srflags;
	srflags = get_reg(task, PT_SR) & ~(TRACE_BITS << 16);
	put_reg(task, PT_SR, srflags);
}

/*
 * Called by kernel/ptrace.c when detaching..
 *
 * Make sure the single step bit is not set.
 */
void ptrace_disable(struct task_struct *child)
{
	/* make sure the single step bit is not set. */
	user_disable_single_step(child);
}

long arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
	int ret;

	switch (request) {
		/* read the word at location addr in the USER area. */
		case PTRACE_PEEKUSR: {
			unsigned long tmp;
			
			ret = -EIO;
			if ((addr & 3) || addr < 0 ||
			    addr > sizeof(struct user) - 3)
				break;
			
			tmp = 0;  /* Default return condition */
			addr = addr >> 2; /* temporary hack. */
			ret = -EIO;
			if (addr < 19) {
				tmp = get_reg(child, addr);
				if (addr == PT_SR)
					tmp >>= 16;
			} else if (addr >= 21 && addr < 49) {
				tmp = child->thread.fp[addr - 21];
#ifdef CONFIG_M68KFPU_EMU
				/* Convert internal fpu reg representation
				 * into long double format
				 */
				if (FPU_IS_EMU && (addr < 45) && !(addr % 3))
					tmp = ((tmp & 0xffff0000) << 15) |
					      ((tmp & 0x0000ffff) << 16);
#endif
			} else if (addr == 49) {
				tmp = child->mm->start_code;
			} else if (addr == 50) {
				tmp = child->mm->start_data;
			} else if (addr == 51) {
				tmp = child->mm->end_code;
			} else
				break;
			ret = put_user(tmp,(unsigned long *) data);
			break;
		}

		case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
			ret = -EIO;
			if ((addr & 3) || addr < 0 ||
			    addr > sizeof(struct user) - 3)
				break;

			addr = addr >> 2; /* temporary hack. */
			    
			if (addr == PT_SR) {
				data &= SR_MASK;
				data <<= 16;
				data |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
			}
			if (addr < 19) {
				if (put_reg(child, addr, data))
					break;
				ret = 0;
				break;
			}
			if (addr >= 21 && addr < 48)
			{
#ifdef CONFIG_M68KFPU_EMU
				/* Convert long double format
				 * into internal fpu reg representation
				 */
				if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) {
					data = (unsigned long)data << 15;
					data = (data & 0xffff0000) |
					       ((data & 0x0000ffff) >> 1);
				}
#endif
				child->thread.fp[addr - 21] = data;
				ret = 0;
			}
			break;

		case PTRACE_GETREGS: { /* Get all gp regs from the child. */
		  	int i;
			unsigned long tmp;
			for (i = 0; i < 19; i++) {
			    tmp = get_reg(child, i);
			    if (i == PT_SR)
				tmp >>= 16;
			    if (put_user(tmp, (unsigned long *) data)) {
				ret = -EFAULT;
				break;
			    }
			    data += sizeof(long);
			}
			ret = 0;
			break;
		}

		case PTRACE_SETREGS: { /* Set all gp regs in the child. */
			int i;
			unsigned long tmp;
			for (i = 0; i < 19; i++) {
			    if (get_user(tmp, (unsigned long *) data)) {
				ret = -EFAULT;
				break;
			    }
			    if (i == PT_SR) {
				tmp &= SR_MASK;
				tmp <<= 16;
				tmp |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
			    }
			    put_reg(child, i, tmp);
			    data += sizeof(long);
			}
			ret = 0;
			break;
		}

#ifdef PTRACE_GETFPREGS
		case PTRACE_GETFPREGS: { /* Get the child FPU state. */
			ret = 0;
			if (copy_to_user((void *)data, &child->thread.fp,
					 sizeof(struct user_m68kfp_struct)))
				ret = -EFAULT;
			break;
		}
#endif

#ifdef PTRACE_SETFPREGS
		case PTRACE_SETFPREGS: { /* Set the child FPU state. */
			ret = 0;
			if (copy_from_user(&child->thread.fp, (void *)data,
					   sizeof(struct user_m68kfp_struct)))
				ret = -EFAULT;
			break;
		}
#endif

	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;
}

asmlinkage void syscall_trace(void)
{
	if (!test_thread_flag(TIF_SYSCALL_TRACE))
		return;
	if (!(current->ptrace & PT_PTRACED))
		return;
	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/m68knommu/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. */
	38	#define TRACE_BITS 0x8000
	39
	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),
	53	};
	54
	55	/*
	56	* Get contents of register REGNO in task TASK.
	57	*/
	58	static inline long get_reg(struct task_struct *task, int regno)
	59	{
	60	unsigned long *addr;
	61
	62	if (regno == PT_USP)
	63	addr = &task->thread.usp;
bf0059b2	64	else if (regno < ARRAY_SIZE(regoff))
1da177e4 LT	65	addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
	66	else
	67	return 0;
	68	return *addr;
	69	}
	70
	71	/*
	72	* Write contents of register REGNO in task TASK.
	73	*/
	74	static inline int put_reg(struct task_struct *task, int regno,
	75	unsigned long data)
	76	{
	77	unsigned long *addr;
	78
	79	if (regno == PT_USP)
	80	addr = &task->thread.usp;
bf0059b2	81	else if (regno < ARRAY_SIZE(regoff))
1da177e4 LT	82	addr = (unsigned long *) (task->thread.esp0 + regoff[regno]);
	83	else
	84	return -1;
	85	*addr = data;
	86	return 0;
	87	}
	88
f60a5572 GU	89	void user_enable_single_step(struct task_struct *task)
	90	{
	91	unsigned long srflags;
	92	srflags = get_reg(task, PT_SR) \| (TRACE_BITS << 16);
	93	put_reg(task, PT_SR, srflags);
	94	}
	95
	96	void user_disable_single_step(struct task_struct *task)
	97	{
	98	unsigned long srflags;
	99	srflags = get_reg(task, PT_SR) & ~(TRACE_BITS << 16);
	100	put_reg(task, PT_SR, srflags);
	101	}
	102
1da177e4 LT	103	/*
	104	* Called by kernel/ptrace.c when detaching..
	105	*
	106	* Make sure the single step bit is not set.
	107	*/
	108	void ptrace_disable(struct task_struct *child)
	109	{
1da177e4	110	/* make sure the single step bit is not set. */
f60a5572	111	user_disable_single_step(child);
1da177e4 LT	112	}
1da177e4 LT	113
afc7cd89	114	long arch_ptrace(struct task_struct *child, long request, long addr, long data)
1da177e4	115	{
1da177e4 LT	116	int ret;
1da177e4 LT	117
1da177e4	118	switch (request) {
1da177e4 LT	119	/* read the word at location addr in the USER area. */
	120	case PTRACE_PEEKUSR: {
	121	unsigned long tmp;
	122
	123	ret = -EIO;
	124	if ((addr & 3) \|\| addr < 0 \|\|
	125	addr > sizeof(struct user) - 3)
	126	break;
	127
	128	tmp = 0; /* Default return condition */
	129	addr = addr >> 2; /* temporary hack. */
	130	ret = -EIO;
	131	if (addr < 19) {
	132	tmp = get_reg(child, addr);
	133	if (addr == PT_SR)
	134	tmp >>= 16;
	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
	140	*/
	141	if (FPU_IS_EMU && (addr < 45) && !(addr % 3))
	142	tmp = ((tmp & 0xffff0000) << 15) \|
	143	((tmp & 0x0000ffff) << 16);
	144	#endif
	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;
	151	} else
	152	break;
	153	ret = put_user(tmp,(unsigned long *) data);
	154	break;
	155	}
	156
1da177e4 LT	157	case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
	158	ret = -EIO;
	159	if ((addr & 3) \|\| addr < 0 \|\|
	160	addr > sizeof(struct user) - 3)
	161	break;
	162
	163	addr = addr >> 2; /* temporary hack. */
	164
	165	if (addr == PT_SR) {
	166	data &= SR_MASK;
	167	data <<= 16;
	168	data \|= get_reg(child, PT_SR) & ~(SR_MASK << 16);
	169	}
	170	if (addr < 19) {
	171	if (put_reg(child, addr, data))
	172	break;
	173	ret = 0;
	174	break;
	175	}
	176	if (addr >= 21 && addr < 48)
	177	{
	178	#ifdef CONFIG_M68KFPU_EMU
	179	/* Convert long double format
	180	* into internal fpu reg representation
	181	*/
	182	if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) {
	183	data = (unsigned long)data << 15;
	184	data = (data & 0xffff0000) \|
	185	((data & 0x0000ffff) >> 1);
	186	}
	187	#endif
	188	child->thread.fp[addr - 21] = data;
	189	ret = 0;
	190	}
	191	break;
	192
1da177e4 LT	193	case PTRACE_GETREGS: { /* Get all gp regs from the child. */
	194	int i;
	195	unsigned long tmp;
	196	for (i = 0; i < 19; i++) {
	197	tmp = get_reg(child, i);
	198	if (i == PT_SR)
	199	tmp >>= 16;
	200	if (put_user(tmp, (unsigned long *) data)) {
	201	ret = -EFAULT;
	202	break;
	203	}
	204	data += sizeof(long);
	205	}
	206	ret = 0;
	207	break;
	208	}
	209
	210	case PTRACE_SETREGS: { /* Set all gp regs in the child. */
	211	int i;
	212	unsigned long tmp;
	213	for (i = 0; i < 19; i++) {
	214	if (get_user(tmp, (unsigned long *) data)) {
	215	ret = -EFAULT;
	216	break;
	217	}
	218	if (i == PT_SR) {
	219	tmp &= SR_MASK;
	220	tmp <<= 16;
	221	tmp \|= get_reg(child, PT_SR) & ~(SR_MASK << 16);
	222	}
	223	put_reg(child, i, tmp);
	224	data += sizeof(long);
	225	}
	226	ret = 0;
	227	break;
	228	}
	229
	230	#ifdef PTRACE_GETFPREGS
	231	case PTRACE_GETFPREGS: { /* Get the child FPU state. */
	232	ret = 0;
	233	if (copy_to_user((void *)data, &child->thread.fp,
	234	sizeof(struct user_m68kfp_struct)))
	235	ret = -EFAULT;
	236	break;
	237	}
	238	#endif
	239
	240	#ifdef PTRACE_SETFPREGS
	241	case PTRACE_SETFPREGS: { /* Set the child FPU state. */
	242	ret = 0;
	243	if (copy_from_user(&child->thread.fp, (void *)data,
	244	sizeof(struct user_m68kfp_struct)))
	245	ret = -EFAULT;
	246	break;
	247	}
	248	#endif
	249
a58f7534 MK	250	case PTRACE_GET_THREAD_AREA:
	251	ret = put_user(task_thread_info(child)->tp_value,
	252	(unsigned long __user *)data);
	253	break;
	254
1da177e4	255	default:
b3c1e01a	256	ret = ptrace_request(child, request, addr, data);
1da177e4 LT	257	break;
1da177e4 LT	258	}
1da177e4 LT	259	return ret;
	260	}
	261
	262	asmlinkage void syscall_trace(void)
	263	{
	264	if (!test_thread_flag(TIF_SYSCALL_TRACE))
	265	return;
	266	if (!(current->ptrace & PT_PTRACED))
	267	return;
	268	ptrace_notify(SIGTRAP \| ((current->ptrace & PT_TRACESYSGOOD)
	269	? 0x80 : 0));
	270	/*
	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
	274	*/
	275	if (current->exit_code) {
	276	send_sig(current->exit_code, current, 1);
	277	current->exit_code = 0;
	278	}
	279	}