[net-next-2.6.git] / arch / tile / kernel / ptrace.c

/*
 * Copyright 2010 Tilera Corporation. All Rights Reserved.
 *
 *   This program is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU General Public License
 *   as published by the Free Software Foundation, version 2.
 *
 *   This program is distributed in the hope that it will be useful, but
 *   WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 *   NON INFRINGEMENT.  See the GNU General Public License for
 *   more details.
 *
 * Copied from i386: Ross Biro 1/23/92
 */

#include <linux/kernel.h>
#include <linux/ptrace.h>
#include <linux/kprobes.h>
#include <linux/compat.h>
#include <linux/uaccess.h>
#include <asm/traps.h>

void user_enable_single_step(struct task_struct *child)
{
	set_tsk_thread_flag(child, TIF_SINGLESTEP);
}

void user_disable_single_step(struct task_struct *child)
{
	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
}

/*
 * Called by kernel/ptrace.c when detaching..
 */
void ptrace_disable(struct task_struct *child)
{
	clear_tsk_thread_flag(child, TIF_SINGLESTEP);

	/*
	 * These two are currently unused, but will be set by arch_ptrace()
	 * and used in the syscall assembly when we do support them.
	 */
	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
}

long arch_ptrace(struct task_struct *child, long request,
		 unsigned long addr, unsigned long data)
{
	unsigned long __user *datap = (long __user __force *)data;
	unsigned long tmp;
	long ret = -EIO;
	char *childreg;
	struct pt_regs copyregs;
	int ex1_offset;

	switch (request) {

	case PTRACE_PEEKUSR:  /* Read register from pt_regs. */
		if (addr >= PTREGS_SIZE)
			break;
		childreg = (char *)task_pt_regs(child) + addr;
#ifdef CONFIG_COMPAT
		if (is_compat_task()) {
			if (addr & (sizeof(compat_long_t)-1))
				break;
			ret = put_user(*(compat_long_t *)childreg,
				       (compat_long_t __user *)datap);
		} else
#endif
		{
			if (addr & (sizeof(long)-1))
				break;
			ret = put_user(*(long *)childreg, datap);
		}
		break;

	case PTRACE_POKEUSR:  /* Write register in pt_regs. */
		if (addr >= PTREGS_SIZE)
			break;
		childreg = (char *)task_pt_regs(child) + addr;

		/* Guard against overwrites of the privilege level. */
		ex1_offset = PTREGS_OFFSET_EX1;
#if defined(CONFIG_COMPAT) && defined(__BIG_ENDIAN)
		if (is_compat_task())   /* point at low word */
			ex1_offset += sizeof(compat_long_t);
#endif
		if (addr == ex1_offset)
			data = PL_ICS_EX1(USER_PL, EX1_ICS(data));

#ifdef CONFIG_COMPAT
		if (is_compat_task()) {
			if (addr & (sizeof(compat_long_t)-1))
				break;
			*(compat_long_t *)childreg = data;
		} else
#endif
		{
			if (addr & (sizeof(long)-1))
				break;
			*(long *)childreg = data;
		}
		ret = 0;
		break;

	case PTRACE_GETREGS:  /* Get all registers from the child. */
		if (copy_to_user(datap, task_pt_regs(child),
				 sizeof(struct pt_regs)) == 0) {
			ret = 0;
		}
		break;

	case PTRACE_SETREGS:  /* Set all registers in the child. */
		if (copy_from_user(&copyregs, datap,
				   sizeof(struct pt_regs)) == 0) {
			copyregs.ex1 =
				PL_ICS_EX1(USER_PL, EX1_ICS(copyregs.ex1));
			*task_pt_regs(child) = copyregs;
			ret = 0;
		}
		break;

	case PTRACE_GETFPREGS:  /* Get the child FPU state. */
	case PTRACE_SETFPREGS:  /* Set the child FPU state. */
		break;

	case PTRACE_SETOPTIONS:
		/* Support TILE-specific ptrace options. */
		child->ptrace &= ~PT_TRACE_MASK_TILE;
		tmp = data & PTRACE_O_MASK_TILE;
		data &= ~PTRACE_O_MASK_TILE;
		ret = ptrace_request(child, request, addr, data);
		if (tmp & PTRACE_O_TRACEMIGRATE)
			child->ptrace |= PT_TRACE_MIGRATE;
		break;

	default:
#ifdef CONFIG_COMPAT
		if (task_thread_info(current)->status & TS_COMPAT) {
			ret = compat_ptrace_request(child, request,
						    addr, data);
			break;
		}
#endif
		ret = ptrace_request(child, request, addr, data);
		break;
	}

	return ret;
}

#ifdef CONFIG_COMPAT
/* Not used; we handle compat issues in arch_ptrace() directly. */
long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
			       compat_ulong_t addr, compat_ulong_t data)
{
	BUG();
}
#endif

void do_syscall_trace(void)
{
	if (!test_thread_flag(TIF_SYSCALL_TRACE))
		return;

	if (!(current->ptrace & PT_PTRACED))
		return;

	/*
	 * The 0x80 provides a way for the tracing parent to distinguish
	 * between a syscall stop and SIGTRAP delivery
	 */
	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;
	}
}

void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
{
	struct siginfo info;

	memset(&info, 0, sizeof(info));
	info.si_signo = SIGTRAP;
	info.si_code  = TRAP_BRKPT;
	info.si_addr  = (void __user *) regs->pc;

	/* Send us the fakey SIGTRAP */
	force_sig_info(SIGTRAP, &info, tsk);
}

/* Handle synthetic interrupt delivered only by the simulator. */
void __kprobes do_breakpoint(struct pt_regs* regs, int fault_num)
{
	send_sigtrap(current, regs, fault_num);
}
Commit	Line	Data
867e359b CM	1	/*
	2	* Copyright 2010 Tilera Corporation. All Rights Reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License
	6	* as published by the Free Software Foundation, version 2.
	7	*
	8	* This program is distributed in the hope that it will be useful, but
	9	* WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
	11	* NON INFRINGEMENT. See the GNU General Public License for
	12	* more details.
	13	*
	14	* Copied from i386: Ross Biro 1/23/92
	15	*/
	16
	17	#include <linux/kernel.h>
	18	#include <linux/ptrace.h>
	19	#include <linux/kprobes.h>
	20	#include <linux/compat.h>
	21	#include <linux/uaccess.h>
0707ad30	22	#include <asm/traps.h>
867e359b CM	23
	24	void user_enable_single_step(struct task_struct *child)
	25	{
	26	set_tsk_thread_flag(child, TIF_SINGLESTEP);
	27	}
	28
	29	void user_disable_single_step(struct task_struct *child)
	30	{
	31	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
	32	}
	33
867e359b CM	34	/*
	35	* Called by kernel/ptrace.c when detaching..
	36	*/
	37	void ptrace_disable(struct task_struct *child)
	38	{
	39	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
	40
	41	/*
	42	* These two are currently unused, but will be set by arch_ptrace()
	43	* and used in the syscall assembly when we do support them.
	44	*/
	45	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
	46	}
	47
9b05a69e NK	48	long arch_ptrace(struct task_struct *child, long request,
9b05a69e NK	49	unsigned long addr, unsigned long data)
867e359b	50	{
ce7f2a39	51	unsigned long __user datap = (long __user __force )data;
867e359b	52	unsigned long tmp;
867e359b	53	long ret = -EIO;
ce7f2a39	54	char *childreg;
1deb9c5d CM	55	struct pt_regs copyregs;
1deb9c5d CM	56	int ex1_offset;
867e359b CM	57
	58	switch (request) {
	59
	60	case PTRACE_PEEKUSR: /* Read register from pt_regs. */
8c0acac3	61	if (addr >= PTREGS_SIZE)
867e359b	62	break;
ce7f2a39 CM	63	childreg = (char *)task_pt_regs(child) + addr;
	64	#ifdef CONFIG_COMPAT
	65	if (is_compat_task()) {
	66	if (addr & (sizeof(compat_long_t)-1))
	67	break;
	68	ret = put_user((compat_long_t )childreg,
	69	(compat_long_t __user *)datap);
	70	} else
	71	#endif
	72	{
	73	if (addr & (sizeof(long)-1))
	74	break;
	75	ret = put_user((long )childreg, datap);
	76	}
867e359b CM	77	break;
	78
	79	case PTRACE_POKEUSR: /* Write register in pt_regs. */
8c0acac3	80	if (addr >= PTREGS_SIZE)
867e359b	81	break;
ce7f2a39	82	childreg = (char *)task_pt_regs(child) + addr;
1deb9c5d CM	83
	84	/* Guard against overwrites of the privilege level. */
	85	ex1_offset = PTREGS_OFFSET_EX1;
	86	#if defined(CONFIG_COMPAT) && defined(__BIG_ENDIAN)
	87	if (is_compat_task()) /* point at low word */
	88	ex1_offset += sizeof(compat_long_t);
	89	#endif
	90	if (addr == ex1_offset)
	91	data = PL_ICS_EX1(USER_PL, EX1_ICS(data));
	92
ce7f2a39 CM	93	#ifdef CONFIG_COMPAT
	94	if (is_compat_task()) {
	95	if (addr & (sizeof(compat_long_t)-1))
	96	break;
	97	(compat_long_t )childreg = data;
	98	} else
	99	#endif
	100	{
	101	if (addr & (sizeof(long)-1))
	102	break;
	103	(long )childreg = data;
	104	}
bcd97c3f	105	ret = 0;
867e359b CM	106	break;
	107
	108	case PTRACE_GETREGS: /* Get all registers from the child. */
1deb9c5d CM	109	if (copy_to_user(datap, task_pt_regs(child),
	110	sizeof(struct pt_regs)) == 0) {
	111	ret = 0;
867e359b CM	112	}
	113	break;
	114
	115	case PTRACE_SETREGS: /* Set all registers in the child. */
1deb9c5d CM	116	if (copy_from_user(&copyregs, datap,
	117	sizeof(struct pt_regs)) == 0) {
	118	copyregs.ex1 =
	119	PL_ICS_EX1(USER_PL, EX1_ICS(copyregs.ex1));
	120	*task_pt_regs(child) = copyregs;
	121	ret = 0;
867e359b CM	122	}
	123	break;
	124
	125	case PTRACE_GETFPREGS: /* Get the child FPU state. */
	126	case PTRACE_SETFPREGS: /* Set the child FPU state. */
	127	break;
	128
	129	case PTRACE_SETOPTIONS:
	130	/* Support TILE-specific ptrace options. */
	131	child->ptrace &= ~PT_TRACE_MASK_TILE;
	132	tmp = data & PTRACE_O_MASK_TILE;
	133	data &= ~PTRACE_O_MASK_TILE;
	134	ret = ptrace_request(child, request, addr, data);
	135	if (tmp & PTRACE_O_TRACEMIGRATE)
	136	child->ptrace \|= PT_TRACE_MIGRATE;
	137	break;
	138
	139	default:
	140	#ifdef CONFIG_COMPAT
	141	if (task_thread_info(current)->status & TS_COMPAT) {
	142	ret = compat_ptrace_request(child, request,
	143	addr, data);
	144	break;
	145	}
	146	#endif
	147	ret = ptrace_request(child, request, addr, data);
	148	break;
	149	}
	150
	151	return ret;
	152	}
	153
	154	#ifdef CONFIG_COMPAT
	155	/* Not used; we handle compat issues in arch_ptrace() directly. */
	156	long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
	157	compat_ulong_t addr, compat_ulong_t data)
	158	{
	159	BUG();
	160	}
	161	#endif
	162
	163	void do_syscall_trace(void)
	164	{
	165	if (!test_thread_flag(TIF_SYSCALL_TRACE))
	166	return;
	167
	168	if (!(current->ptrace & PT_PTRACED))
	169	return;
	170
	171	/*
	172	* The 0x80 provides a way for the tracing parent to distinguish
	173	* between a syscall stop and SIGTRAP delivery
	174	*/
	175	ptrace_notify(SIGTRAP\|((current->ptrace & PT_TRACESYSGOOD) ? 0x80 : 0));
	176
	177	/*
	178	* this isn't the same as continuing with a signal, but it will do
	179	* for normal use. strace only continues with a signal if the
	180	* stopping signal is not SIGTRAP. -brl
	181	*/
	182	if (current->exit_code) {
	183	send_sig(current->exit_code, current, 1);
	184	current->exit_code = 0;
	185	}
186	}
187
188	void send_sigtrap(struct task_struct tsk, struct pt_regs regs, int error_code)
189	{
190	struct siginfo info;
191
192	memset(&info, 0, sizeof(info));
193	info.si_signo = SIGTRAP;
194	info.si_code = TRAP_BRKPT;
195	info.si_addr = (void __user *) regs->pc;
196
197	/* Send us the fakey SIGTRAP */
198	force_sig_info(SIGTRAP, &info, tsk);
199	}
200
201	/* Handle synthetic interrupt delivered only by the simulator. */
202	void __kprobes do_breakpoint(struct pt_regs* regs, int fault_num)
203	{
204	send_sigtrap(current, regs, fault_num);
205	}