arch/powerpc/kernel/ptrace32.c - kernel/msm-4.9 - Gitiles

 /*
  * ptrace for 32-bit processes running on a 64-bit kernel.
  *
  *  PowerPC version
  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  *
  *  Derived from "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
  *
  * Modified by Cort Dougan (cort@hq.fsmlabs.com)
  * and Paul Mackerras (paulus@samba.org).
  *
  * 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/smp_lock.h>
 #include <linux/errno.h>
 #include <linux/ptrace.h>
 #include <linux/user.h>
 #include <linux/security.h>
 #include <linux/signal.h>

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

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

 /*
  * Here are the old "legacy" powerpc specific getregs/setregs ptrace calls,
  * we mark them as obsolete now, they will be removed in a future version
  */
 static long compat_ptrace_old(struct task_struct *child, long request,
 			      long addr, long data)
 {
 	int ret = -EPERM;

 	switch(request) {
 	case PPC_PTRACE_GETREGS: { /* Get GPRs 0 - 31. */
 		int i;
 		unsigned long *reg = &((unsigned long *)child->thread.regs)[0];
 		unsigned int __user *tmp = (unsigned int __user *)addr;

 		for (i = 0; i < 32; i++) {
 			ret = put_user(*reg, tmp);
 			if (ret)
 				break;
 			reg++;
 			tmp++;
 		}
 		break;
 	}

 	case PPC_PTRACE_SETREGS: { /* Set GPRs 0 - 31. */
 		int i;
 		unsigned long *reg = &((unsigned long *)child->thread.regs)[0];
 		unsigned int __user *tmp = (unsigned int __user *)addr;

 		for (i = 0; i < 32; i++) {
 			ret = get_user(*reg, tmp);
 			if (ret)
 				break;
 			reg++;
 			tmp++;
 		}
 		break;
 	}

 	}
 	return ret;
 }

 long compat_sys_ptrace(int request, int pid, unsigned long addr,
 		       unsigned long data)
 {
 	struct task_struct *child;
 	int ret;

 	lock_kernel();
 	if (request == PTRACE_TRACEME) {
 		ret = ptrace_traceme();
 		goto out;
 	}

 	child = ptrace_get_task_struct(pid);
 	if (IS_ERR(child)) {
 		ret = PTR_ERR(child);
 		goto out;
 	}

 	if (request == PTRACE_ATTACH) {
 		ret = ptrace_attach(child);
 		goto out_tsk;
 	}

 	ret = ptrace_check_attach(child, request == PTRACE_KILL);
 	if (ret < 0)
 		goto out_tsk;

 	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: {
 		unsigned int tmp;
 		int copied;

 		copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
 		ret = -EIO;
 		if (copied != sizeof(tmp))
 			break;
 		ret = put_user(tmp, (u32 __user *)data);
 		break;
 	}

 	/*
 	 * Read 4 bytes of the other process' storage
 	 *  data is a pointer specifying where the user wants the
 	 *	4 bytes copied into
 	 *  addr is a pointer in the user's storage that contains an 8 byte
 	 *	address in the other process of the 4 bytes that is to be read
 	 * (this is run in a 32-bit process looking at a 64-bit process)
 	 * when I and D space are separate, these will need to be fixed.
 	 */
 	case PPC_PTRACE_PEEKTEXT_3264:
 	case PPC_PTRACE_PEEKDATA_3264: {
 		u32 tmp;
 		int copied;
 		u32 __user * addrOthers;

 		ret = -EIO;

 		/* Get the addr in the other process that we want to read */
 		if (get_user(addrOthers, (u32 __user * __user *)addr) != 0)
 			break;

 		copied = access_process_vm(child, (u64)addrOthers, &tmp,
 				sizeof(tmp), 0);
 		if (copied != sizeof(tmp))
 			break;
 		ret = put_user(tmp, (u32 __user *)data);
 		break;
 	}

 	/* Read a register (specified by ADDR) out of the "user area" */
 	case PTRACE_PEEKUSR: {
 		int index;
 		unsigned long tmp;

 		ret = -EIO;
 		/* convert to index and check */
 		index = (unsigned long) addr >> 2;
 		if ((addr & 3) || (index > PT_FPSCR32))
 			break;

 		if (index < PT_FPR0) {
 			tmp = ptrace_get_reg(child, index);
 		} else {
 			flush_fp_to_thread(child);
 			/*
 			 * the user space code considers the floating point
 			 * to be an array of unsigned int (32 bits) - the
 			 * index passed in is based on this assumption.
 			 */
 			tmp = ((unsigned int *)child->thread.fpr)[index - PT_FPR0];
 		}
 		ret = put_user((unsigned int)tmp, (u32 __user *)data);
 		break;
 	}

 	/*
 	 * Read 4 bytes out of the other process' pt_regs area
 	 *  data is a pointer specifying where the user wants the
 	 *	4 bytes copied into
 	 *  addr is the offset into the other process' pt_regs structure
 	 *	that is to be read
 	 * (this is run in a 32-bit process looking at a 64-bit process)
 	 */
 	case PPC_PTRACE_PEEKUSR_3264: {
 		u32 index;
 		u32 reg32bits;
 		u64 tmp;
 		u32 numReg;
 		u32 part;

 		ret = -EIO;
 		/* Determine which register the user wants */
 		index = (u64)addr >> 2;
 		numReg = index / 2;
 		/* Determine which part of the register the user wants */
 		if (index % 2)
 			part = 1;  /* want the 2nd half of the register (right-most). */
 		else
 			part = 0;  /* want the 1st half of the register (left-most). */

 		/* Validate the input - check to see if address is on the wrong boundary
 		 * or beyond the end of the user area
 		 */
 		if ((addr & 3) || numReg > PT_FPSCR)
 			break;

 		if (numReg >= PT_FPR0) {
 			flush_fp_to_thread(child);
 			tmp = ((unsigned long int *)child->thread.fpr)[numReg - PT_FPR0];
 		} else { /* register within PT_REGS struct */
 			tmp = ptrace_get_reg(child, numReg);
 		}
 		reg32bits = ((u32*)&tmp)[part];
 		ret = put_user(reg32bits, (u32 __user *)data);
 		break;
 	}

 	/* If I and D space are separate, this will have to be fixed. */
 	case PTRACE_POKETEXT: /* write the word at location addr. */
 	case PTRACE_POKEDATA: {
 		unsigned int tmp;
 		tmp = data;
 		ret = 0;
 		if (access_process_vm(child, addr, &tmp, sizeof(tmp), 1)
 				== sizeof(tmp))
 			break;
 		ret = -EIO;
 		break;
 	}

 	/*
 	 * Write 4 bytes into the other process' storage
 	 *  data is the 4 bytes that the user wants written
 	 *  addr is a pointer in the user's storage that contains an
 	 *	8 byte address in the other process where the 4 bytes
 	 *	that is to be written
 	 * (this is run in a 32-bit process looking at a 64-bit process)
 	 * when I and D space are separate, these will need to be fixed.
 	 */
 	case PPC_PTRACE_POKETEXT_3264:
 	case PPC_PTRACE_POKEDATA_3264: {
 		u32 tmp = data;
 		u32 __user * addrOthers;

 		/* Get the addr in the other process that we want to write into */
 		ret = -EIO;
 		if (get_user(addrOthers, (u32 __user * __user *)addr) != 0)
 			break;
 		ret = 0;
 		if (access_process_vm(child, (u64)addrOthers, &tmp,
 					sizeof(tmp), 1) == sizeof(tmp))
 			break;
 		ret = -EIO;
 		break;
 	}

 	/* write the word at location addr in the USER area */
 	case PTRACE_POKEUSR: {
 		unsigned long index;

 		ret = -EIO;
 		/* convert to index and check */
 		index = (unsigned long) addr >> 2;
 		if ((addr & 3) || (index > PT_FPSCR32))
 			break;

 		if (index < PT_FPR0) {
 			ret = ptrace_put_reg(child, index, data);
 		} else {
 			flush_fp_to_thread(child);
 			/*
 			 * the user space code considers the floating point
 			 * to be an array of unsigned int (32 bits) - the
 			 * index passed in is based on this assumption.
 			 */
 			((unsigned int *)child->thread.fpr)[index - PT_FPR0] = data;
 			ret = 0;
 		}
 		break;
 	}

 	/*
 	 * Write 4 bytes into the other process' pt_regs area
 	 *  data is the 4 bytes that the user wants written
 	 *  addr is the offset into the other process' pt_regs structure
 	 *	that is to be written into
 	 * (this is run in a 32-bit process looking at a 64-bit process)
 	 */
 	case PPC_PTRACE_POKEUSR_3264: {
 		u32 index;
 		u32 numReg;

 		ret = -EIO;
 		/* Determine which register the user wants */
 		index = (u64)addr >> 2;
 		numReg = index / 2;

 		/*
 		 * Validate the input - check to see if address is on the
 		 * wrong boundary or beyond the end of the user area
 		 */
 		if ((addr & 3) || (numReg > PT_FPSCR))
 			break;
 		if (numReg < PT_FPR0) {
 			unsigned long freg = ptrace_get_reg(child, numReg);
 			if (index % 2)
 				freg = (freg & ~0xfffffffful) | (data & 0xfffffffful);
 			else
 				freg = (freg & 0xfffffffful) | (data << 32);
 			ret = ptrace_put_reg(child, numReg, freg);
 		} else {
 			flush_fp_to_thread(child);
 			((unsigned int *)child->thread.regs)[index] = data;
 			ret = 0;
 		}
 		break;
 	}

 	case PTRACE_GET_DEBUGREG: {
 		ret = -EINVAL;
 		/* We only support one DABR and no IABRS at the moment */
 		if (addr > 0)
 			break;
 		ret = put_user(child->thread.dabr, (u32 __user *)data);
 		break;
 	}

 	case PTRACE_GETEVENTMSG:
 		ret = put_user(child->ptrace_message, (unsigned int __user *) data);
 		break;

 	case PTRACE_GETREGS: { /* Get all pt_regs from the child. */
 		int ui;
 	  	if (!access_ok(VERIFY_WRITE, (void __user *)data,
 			       PT_REGS_COUNT * sizeof(int))) {
 			ret = -EIO;
 			break;
 		}
 		ret = 0;
 		for (ui = 0; ui < PT_REGS_COUNT; ui ++) {
 			ret |= __put_user(ptrace_get_reg(child, ui),
 					  (unsigned int __user *) data);
 			data += sizeof(int);
 		}
 		break;
 	}

 	case PTRACE_SETREGS: { /* Set all gp regs in the child. */
 		unsigned long tmp;
 		int ui;
 	  	if (!access_ok(VERIFY_READ, (void __user *)data,
 			       PT_REGS_COUNT * sizeof(int))) {
 			ret = -EIO;
 			break;
 		}
 		ret = 0;
 		for (ui = 0; ui < PT_REGS_COUNT; ui ++) {
 			ret = __get_user(tmp, (unsigned int __user *) data);
 			if (ret)
 				break;
 			ptrace_put_reg(child, ui, tmp);
 			data += sizeof(int);
 		}
 		break;
 	}

 	case PTRACE_GETFPREGS:
 	case PTRACE_SETFPREGS:
 	case PTRACE_GETVRREGS:
 	case PTRACE_SETVRREGS:
 	case PTRACE_GETREGS64:
 	case PTRACE_SETREGS64:
 	case PPC_PTRACE_GETFPREGS:
 	case PPC_PTRACE_SETFPREGS:
 	case PTRACE_KILL:
 	case PTRACE_SINGLESTEP:
 	case PTRACE_DETACH:
 	case PTRACE_SET_DEBUGREG:
 	case PTRACE_SYSCALL:
 	case PTRACE_CONT:
 		ret = arch_ptrace(child, request, addr, data);
 		break;

 	/* Old reverse args ptrace callss */
 	case PPC_PTRACE_GETREGS: /* Get GPRs 0 - 31. */
 	case PPC_PTRACE_SETREGS: /* Set GPRs 0 - 31. */
 		ret = compat_ptrace_old(child, request, addr, data);
 		break;

 	default:
 		ret = ptrace_request(child, request, addr, data);
 		break;
 	}
 out_tsk:
 	put_task_struct(child);
 out:
 	unlock_kernel();
 	return ret;
 }
	/*
	* ptrace for 32-bit processes running on a 64-bit kernel.
	*
	* PowerPC version
	* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
	*
	* Derived from "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
	*
	* Modified by Cort Dougan (cort@hq.fsmlabs.com)
	* and Paul Mackerras (paulus@samba.org).
	*
	* 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/smp_lock.h>
	#include <linux/errno.h>
	#include <linux/ptrace.h>
	#include <linux/user.h>
	#include <linux/security.h>
	#include <linux/signal.h>

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

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

	/*
	* Here are the old "legacy" powerpc specific getregs/setregs ptrace calls,
	* we mark them as obsolete now, they will be removed in a future version
	*/
	static long compat_ptrace_old(struct task_struct *child, long request,
	long addr, long data)
	{
	int ret = -EPERM;

	switch(request) {
	case PPC_PTRACE_GETREGS: { /* Get GPRs 0 - 31. */
	int i;
	unsigned long reg = &((unsigned long )child->thread.regs)[0];
	unsigned int __user tmp = (unsigned int __user )addr;

	for (i = 0; i < 32; i++) {
	ret = put_user(*reg, tmp);
	if (ret)
	break;
	reg++;
	tmp++;
	}
	break;
	}

	case PPC_PTRACE_SETREGS: { /* Set GPRs 0 - 31. */
	int i;
	unsigned long reg = &((unsigned long )child->thread.regs)[0];
	unsigned int __user tmp = (unsigned int __user )addr;

	for (i = 0; i < 32; i++) {
	ret = get_user(*reg, tmp);
	if (ret)
	break;
	reg++;
	tmp++;
	}
	break;
	}

	}
	return ret;
	}

	long compat_sys_ptrace(int request, int pid, unsigned long addr,
	unsigned long data)
	{
	struct task_struct *child;
	int ret;

	lock_kernel();
	if (request == PTRACE_TRACEME) {
	ret = ptrace_traceme();
	goto out;
	}

	child = ptrace_get_task_struct(pid);
	if (IS_ERR(child)) {
	ret = PTR_ERR(child);
	goto out;
	}

	if (request == PTRACE_ATTACH) {
	ret = ptrace_attach(child);
	goto out_tsk;
	}

	ret = ptrace_check_attach(child, request == PTRACE_KILL);
	if (ret < 0)
	goto out_tsk;

	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: {
	unsigned int tmp;
	int copied;

	copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
	ret = -EIO;
	if (copied != sizeof(tmp))
	break;
	ret = put_user(tmp, (u32 __user *)data);
	break;
	}

	/*
	* Read 4 bytes of the other process' storage
	* data is a pointer specifying where the user wants the
	* 4 bytes copied into
	* addr is a pointer in the user's storage that contains an 8 byte
	* address in the other process of the 4 bytes that is to be read
	* (this is run in a 32-bit process looking at a 64-bit process)
	* when I and D space are separate, these will need to be fixed.
	*/
	case PPC_PTRACE_PEEKTEXT_3264:
	case PPC_PTRACE_PEEKDATA_3264: {
	u32 tmp;
	int copied;
	u32 __user * addrOthers;

	ret = -EIO;

	/* Get the addr in the other process that we want to read */
	if (get_user(addrOthers, (u32 __user * __user *)addr) != 0)
	break;

	copied = access_process_vm(child, (u64)addrOthers, &tmp,
	sizeof(tmp), 0);
	if (copied != sizeof(tmp))
	break;
	ret = put_user(tmp, (u32 __user *)data);
	break;
	}

	/* Read a register (specified by ADDR) out of the "user area" */
	case PTRACE_PEEKUSR: {
	int index;
	unsigned long tmp;

	ret = -EIO;
	/* convert to index and check */
	index = (unsigned long) addr >> 2;
	if ((addr & 3) \|\| (index > PT_FPSCR32))
	break;

	if (index < PT_FPR0) {
	tmp = ptrace_get_reg(child, index);
	} else {
	flush_fp_to_thread(child);
	/*
	* the user space code considers the floating point
	* to be an array of unsigned int (32 bits) - the
	* index passed in is based on this assumption.
	*/
	tmp = ((unsigned int *)child->thread.fpr)[index - PT_FPR0];
	}
	ret = put_user((unsigned int)tmp, (u32 __user *)data);
	break;
	}

	/*
	* Read 4 bytes out of the other process' pt_regs area
	* data is a pointer specifying where the user wants the
	* 4 bytes copied into
	* addr is the offset into the other process' pt_regs structure
	* that is to be read
	* (this is run in a 32-bit process looking at a 64-bit process)
	*/
	case PPC_PTRACE_PEEKUSR_3264: {
	u32 index;
	u32 reg32bits;
	u64 tmp;
	u32 numReg;
	u32 part;

	ret = -EIO;
	/* Determine which register the user wants */
	index = (u64)addr >> 2;
	numReg = index / 2;
	/* Determine which part of the register the user wants */
	if (index % 2)
	part = 1; /* want the 2nd half of the register (right-most). */
	else
	part = 0; /* want the 1st half of the register (left-most). */

	/* Validate the input - check to see if address is on the wrong boundary
	* or beyond the end of the user area
	*/
	if ((addr & 3) \|\| numReg > PT_FPSCR)
	break;

	if (numReg >= PT_FPR0) {
	flush_fp_to_thread(child);
	tmp = ((unsigned long int *)child->thread.fpr)[numReg - PT_FPR0];
	} else { /* register within PT_REGS struct */
	tmp = ptrace_get_reg(child, numReg);
	}
	reg32bits = ((u32*)&tmp)[part];
	ret = put_user(reg32bits, (u32 __user *)data);
	break;
	}

	/* If I and D space are separate, this will have to be fixed. */
	case PTRACE_POKETEXT: /* write the word at location addr. */
	case PTRACE_POKEDATA: {
	unsigned int tmp;
	tmp = data;
	ret = 0;
	if (access_process_vm(child, addr, &tmp, sizeof(tmp), 1)
	== sizeof(tmp))
	break;
	ret = -EIO;
	break;
	}

	/*
	* Write 4 bytes into the other process' storage
	* data is the 4 bytes that the user wants written
	* addr is a pointer in the user's storage that contains an
	* 8 byte address in the other process where the 4 bytes
	* that is to be written
	* (this is run in a 32-bit process looking at a 64-bit process)
	* when I and D space are separate, these will need to be fixed.
	*/
	case PPC_PTRACE_POKETEXT_3264:
	case PPC_PTRACE_POKEDATA_3264: {
	u32 tmp = data;
	u32 __user * addrOthers;

	/* Get the addr in the other process that we want to write into */
	ret = -EIO;
	if (get_user(addrOthers, (u32 __user * __user *)addr) != 0)
	break;
	ret = 0;
	if (access_process_vm(child, (u64)addrOthers, &tmp,
	sizeof(tmp), 1) == sizeof(tmp))
	break;
	ret = -EIO;
	break;
	}

	/* write the word at location addr in the USER area */
	case PTRACE_POKEUSR: {
	unsigned long index;

	ret = -EIO;
	/* convert to index and check */
	index = (unsigned long) addr >> 2;
	if ((addr & 3) \|\| (index > PT_FPSCR32))
	break;

	if (index < PT_FPR0) {
	ret = ptrace_put_reg(child, index, data);
	} else {
	flush_fp_to_thread(child);
	/*
	* the user space code considers the floating point
	* to be an array of unsigned int (32 bits) - the
	* index passed in is based on this assumption.
	*/
	((unsigned int *)child->thread.fpr)[index - PT_FPR0] = data;
	ret = 0;
	}
	break;
	}

	/*
	* Write 4 bytes into the other process' pt_regs area
	* data is the 4 bytes that the user wants written
	* addr is the offset into the other process' pt_regs structure
	* that is to be written into
	* (this is run in a 32-bit process looking at a 64-bit process)
	*/
	case PPC_PTRACE_POKEUSR_3264: {
	u32 index;
	u32 numReg;

	ret = -EIO;
	/* Determine which register the user wants */
	index = (u64)addr >> 2;
	numReg = index / 2;

	/*
	* Validate the input - check to see if address is on the
	* wrong boundary or beyond the end of the user area
	*/
	if ((addr & 3) \|\| (numReg > PT_FPSCR))
	break;
	if (numReg < PT_FPR0) {
	unsigned long freg = ptrace_get_reg(child, numReg);
	if (index % 2)
	freg = (freg & ~0xfffffffful) \| (data & 0xfffffffful);
	else
	freg = (freg & 0xfffffffful) \| (data << 32);
	ret = ptrace_put_reg(child, numReg, freg);
	} else {
	flush_fp_to_thread(child);
	((unsigned int *)child->thread.regs)[index] = data;
	ret = 0;
	}
	break;
	}

	case PTRACE_GET_DEBUGREG: {
	ret = -EINVAL;
	/* We only support one DABR and no IABRS at the moment */
	if (addr > 0)
	break;
	ret = put_user(child->thread.dabr, (u32 __user *)data);
	break;
	}

	case PTRACE_GETEVENTMSG:
	ret = put_user(child->ptrace_message, (unsigned int __user *) data);
	break;

	case PTRACE_GETREGS: { /* Get all pt_regs from the child. */
	int ui;
	if (!access_ok(VERIFY_WRITE, (void __user *)data,
	PT_REGS_COUNT * sizeof(int))) {
	ret = -EIO;
	break;
	}
	ret = 0;
	for (ui = 0; ui < PT_REGS_COUNT; ui ++) {
	ret \|= __put_user(ptrace_get_reg(child, ui),
	(unsigned int __user *) data);
	data += sizeof(int);
	}
	break;
	}

	case PTRACE_SETREGS: { /* Set all gp regs in the child. */
	unsigned long tmp;
	int ui;
	if (!access_ok(VERIFY_READ, (void __user *)data,
	PT_REGS_COUNT * sizeof(int))) {
	ret = -EIO;
	break;
	}
	ret = 0;
	for (ui = 0; ui < PT_REGS_COUNT; ui ++) {
	ret = __get_user(tmp, (unsigned int __user *) data);
	if (ret)
	break;
	ptrace_put_reg(child, ui, tmp);
	data += sizeof(int);
	}
	break;
	}

	case PTRACE_GETFPREGS:
	case PTRACE_SETFPREGS:
	case PTRACE_GETVRREGS:
	case PTRACE_SETVRREGS:
	case PTRACE_GETREGS64:
	case PTRACE_SETREGS64:
	case PPC_PTRACE_GETFPREGS:
	case PPC_PTRACE_SETFPREGS:
	case PTRACE_KILL:
	case PTRACE_SINGLESTEP:
	case PTRACE_DETACH:
	case PTRACE_SET_DEBUGREG:
	case PTRACE_SYSCALL:
	case PTRACE_CONT:
	ret = arch_ptrace(child, request, addr, data);
	break;

	/* Old reverse args ptrace callss */
	case PPC_PTRACE_GETREGS: /* Get GPRs 0 - 31. */
	case PPC_PTRACE_SETREGS: /* Set GPRs 0 - 31. */
	ret = compat_ptrace_old(child, request, addr, data);
	break;

	default:
	ret = ptrace_request(child, request, addr, data);
	break;
	}
	out_tsk:
	put_task_struct(child);
	out:
	unlock_kernel();
	return ret;
	}