arch/m68knommu/kernel/ptrace.c - linux - Git at Google

 /*
  *  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) {
 		/* when I and D space are separate, these will need to be fixed. */
 		case PTRACE_PEEKTEXT: /* read word at location addr. */
 		case PTRACE_PEEKDATA:
 			ret = generic_ptrace_peekdata(child, addr, data);
 			break;

 		/* 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;
 		}

 		/* when I and D space are separate, this will have to be fixed. */
 		case PTRACE_POKETEXT: /* write the word at location addr. */
 		case PTRACE_POKEDATA:
 			ret = generic_ptrace_pokedata(child, addr, 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_SYSCALL: /* continue and stop at next (return from) syscall */
 		case PTRACE_CONT: { /* restart after signal. */
 			long tmp;

 			ret = -EIO;
 			if (!valid_signal(data))
 				break;
 			if (request == PTRACE_SYSCALL)
 				set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 			else
 				clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 			child->exit_code = data;
 			/* make sure the single step bit is not set. */
 			tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
 			put_reg(child, PT_SR, tmp);
 			wake_up_process(child);
 			ret = 0;
 			break;
 		}

 		/*
 		 * make the child exit.  Best I can do is send it a sigkill.
 		 * perhaps it should be put in the status that it wants to
 		 * exit.
 		 */
 		case PTRACE_KILL: {
 			long tmp;

 			ret = 0;
 			if (child->exit_state == EXIT_ZOMBIE) /* already dead */
 				break;
 			child->exit_code = SIGKILL;
 			/* make sure the single step bit is not set. */
 			tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
 			put_reg(child, PT_SR, tmp);
 			wake_up_process(child);
 			break;
 		}

 		case PTRACE_SINGLESTEP: {  /* set the trap flag. */
 			long tmp;

 			ret = -EIO;
 			if (!valid_signal(data))
 				break;
 			clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 			tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16);
 			put_reg(child, PT_SR, tmp);

 			child->exit_code = data;
 			/* give it a chance to run. */
 			wake_up_process(child);
 			ret = 0;
 			break;
 		}

 		case PTRACE_DETACH:	/* detach a process that was attached. */
 			ret = ptrace_detach(child, data);
 			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

 		default:
 			ret = -EIO;
 			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;
 	}
 }
	/*
	* 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) {
	/* when I and D space are separate, these will need to be fixed. */
	case PTRACE_PEEKTEXT: /* read word at location addr. */
	case PTRACE_PEEKDATA:
	ret = generic_ptrace_peekdata(child, addr, data);
	break;

	/* 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;
	}

	/* when I and D space are separate, this will have to be fixed. */
	case PTRACE_POKETEXT: /* write the word at location addr. */
	case PTRACE_POKEDATA:
	ret = generic_ptrace_pokedata(child, addr, 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_SYSCALL: /* continue and stop at next (return from) syscall */
	case PTRACE_CONT: { /* restart after signal. */
	long tmp;

	ret = -EIO;
	if (!valid_signal(data))
	break;
	if (request == PTRACE_SYSCALL)
	set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
	else
	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
	child->exit_code = data;
	/* make sure the single step bit is not set. */
	tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
	put_reg(child, PT_SR, tmp);
	wake_up_process(child);
	ret = 0;
	break;
	}

	/*
	* make the child exit. Best I can do is send it a sigkill.
	* perhaps it should be put in the status that it wants to
	* exit.
	*/
	case PTRACE_KILL: {
	long tmp;

	ret = 0;
	if (child->exit_state == EXIT_ZOMBIE) /* already dead */
	break;
	child->exit_code = SIGKILL;
	/* make sure the single step bit is not set. */
	tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
	put_reg(child, PT_SR, tmp);
	wake_up_process(child);
	break;
	}

	case PTRACE_SINGLESTEP: { /* set the trap flag. */
	long tmp;

	ret = -EIO;
	if (!valid_signal(data))
	break;
	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
	tmp = get_reg(child, PT_SR) \| (TRACE_BITS << 16);
	put_reg(child, PT_SR, tmp);

	child->exit_code = data;
	/* give it a chance to run. */
	wake_up_process(child);
	ret = 0;
	break;
	}

	case PTRACE_DETACH: /* detach a process that was attached. */
	ret = ptrace_detach(child, data);
	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

	default:
	ret = -EIO;
	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;
	}
	}