arch/mips/kernel/ptrace.c - maze/linux - Git at Google

 /*
  * 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.
  *
  * Copyright (C) 1992 Ross Biro
  * Copyright (C) Linus Torvalds
  * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
  * Copyright (C) 1996 David S. Miller
  * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
  * Copyright (C) 1999 MIPS Technologies, Inc.
  * Copyright (C) 2000 Ulf Carlsson
  *
  * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
  * binaries.
  */
 #include <linux/compiler.h>
 #include <linux/context_tracking.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/errno.h>
 #include <linux/ptrace.h>
 #include <linux/smp.h>
 #include <linux/user.h>
 #include <linux/security.h>
 #include <linux/audit.h>
 #include <linux/seccomp.h>

 #include <asm/byteorder.h>
 #include <asm/cpu.h>
 #include <asm/dsp.h>
 #include <asm/fpu.h>
 #include <asm/mipsregs.h>
 #include <asm/mipsmtregs.h>
 #include <asm/pgtable.h>
 #include <asm/page.h>
 #include <asm/uaccess.h>
 #include <asm/bootinfo.h>
 #include <asm/reg.h>

 /*
  * Called by kernel/ptrace.c when detaching..
  *
  * Make sure single step bits etc are not set.
  */
 void ptrace_disable(struct task_struct *child)
 {
 	/* Don't load the watchpoint registers for the ex-child. */
 	clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
 }

 /*
  * Read a general register set.	 We always use the 64-bit format, even
  * for 32-bit kernels and for 32-bit processes on a 64-bit kernel.
  * Registers are sign extended to fill the available space.
  */
 int ptrace_getregs(struct task_struct *child, __s64 __user *data)
 {
 	struct pt_regs *regs;
 	int i;

 	if (!access_ok(VERIFY_WRITE, data, 38 * 8))
 		return -EIO;

 	regs = task_pt_regs(child);

 	for (i = 0; i < 32; i++)
 		__put_user((long)regs->regs[i], data + i);
 	__put_user((long)regs->lo, data + EF_LO - EF_R0);
 	__put_user((long)regs->hi, data + EF_HI - EF_R0);
 	__put_user((long)regs->cp0_epc, data + EF_CP0_EPC - EF_R0);
 	__put_user((long)regs->cp0_badvaddr, data + EF_CP0_BADVADDR - EF_R0);
 	__put_user((long)regs->cp0_status, data + EF_CP0_STATUS - EF_R0);
 	__put_user((long)regs->cp0_cause, data + EF_CP0_CAUSE - EF_R0);

 	return 0;
 }

 /*
  * Write a general register set.  As for PTRACE_GETREGS, we always use
  * the 64-bit format.  On a 32-bit kernel only the lower order half
  * (according to endianness) will be used.
  */
 int ptrace_setregs(struct task_struct *child, __s64 __user *data)
 {
 	struct pt_regs *regs;
 	int i;

 	if (!access_ok(VERIFY_READ, data, 38 * 8))
 		return -EIO;

 	regs = task_pt_regs(child);

 	for (i = 0; i < 32; i++)
 		__get_user(regs->regs[i], data + i);
 	__get_user(regs->lo, data + EF_LO - EF_R0);
 	__get_user(regs->hi, data + EF_HI - EF_R0);
 	__get_user(regs->cp0_epc, data + EF_CP0_EPC - EF_R0);

 	/* badvaddr, status, and cause may not be written.  */

 	return 0;
 }

 int ptrace_getfpregs(struct task_struct *child, __u32 __user *data)
 {
 	int i;
 	unsigned int tmp;

 	if (!access_ok(VERIFY_WRITE, data, 33 * 8))
 		return -EIO;

 	if (tsk_used_math(child)) {
 		fpureg_t *fregs = get_fpu_regs(child);
 		for (i = 0; i < 32; i++)
 			__put_user(fregs[i], i + (__u64 __user *) data);
 	} else {
 		for (i = 0; i < 32; i++)
 			__put_user((__u64) -1, i + (__u64 __user *) data);
 	}

 	__put_user(child->thread.fpu.fcr31, data + 64);

 	preempt_disable();
 	if (cpu_has_fpu) {
 		unsigned int flags;

 		if (cpu_has_mipsmt) {
 			unsigned int vpflags = dvpe();
 			flags = read_c0_status();
 			__enable_fpu();
 			__asm__ __volatile__("cfc1\t%0,$0" : "=r" (tmp));
 			write_c0_status(flags);
 			evpe(vpflags);
 		} else {
 			flags = read_c0_status();
 			__enable_fpu();
 			__asm__ __volatile__("cfc1\t%0,$0" : "=r" (tmp));
 			write_c0_status(flags);
 		}
 	} else {
 		tmp = 0;
 	}
 	preempt_enable();
 	__put_user(tmp, data + 65);

 	return 0;
 }

 int ptrace_setfpregs(struct task_struct *child, __u32 __user *data)
 {
 	fpureg_t *fregs;
 	int i;

 	if (!access_ok(VERIFY_READ, data, 33 * 8))
 		return -EIO;

 	fregs = get_fpu_regs(child);

 	for (i = 0; i < 32; i++)
 		__get_user(fregs[i], i + (__u64 __user *) data);

 	__get_user(child->thread.fpu.fcr31, data + 64);

 	/* FIR may not be written.  */

 	return 0;
 }

 int ptrace_get_watch_regs(struct task_struct *child,
 			  struct pt_watch_regs __user *addr)
 {
 	enum pt_watch_style style;
 	int i;

 	if (!cpu_has_watch || current_cpu_data.watch_reg_use_cnt == 0)
 		return -EIO;
 	if (!access_ok(VERIFY_WRITE, addr, sizeof(struct pt_watch_regs)))
 		return -EIO;

 #ifdef CONFIG_32BIT
 	style = pt_watch_style_mips32;
 #define WATCH_STYLE mips32
 #else
 	style = pt_watch_style_mips64;
 #define WATCH_STYLE mips64
 #endif

 	__put_user(style, &addr->style);
 	__put_user(current_cpu_data.watch_reg_use_cnt,
 		   &addr->WATCH_STYLE.num_valid);
 	for (i = 0; i < current_cpu_data.watch_reg_use_cnt; i++) {
 		__put_user(child->thread.watch.mips3264.watchlo[i],
 			   &addr->WATCH_STYLE.watchlo[i]);
 		__put_user(child->thread.watch.mips3264.watchhi[i] & 0xfff,
 			   &addr->WATCH_STYLE.watchhi[i]);
 		__put_user(current_cpu_data.watch_reg_masks[i],
 			   &addr->WATCH_STYLE.watch_masks[i]);
 	}
 	for (; i < 8; i++) {
 		__put_user(0, &addr->WATCH_STYLE.watchlo[i]);
 		__put_user(0, &addr->WATCH_STYLE.watchhi[i]);
 		__put_user(0, &addr->WATCH_STYLE.watch_masks[i]);
 	}

 	return 0;
 }

 int ptrace_set_watch_regs(struct task_struct *child,
 			  struct pt_watch_regs __user *addr)
 {
 	int i;
 	int watch_active = 0;
 	unsigned long lt[NUM_WATCH_REGS];
 	u16 ht[NUM_WATCH_REGS];

 	if (!cpu_has_watch || current_cpu_data.watch_reg_use_cnt == 0)
 		return -EIO;
 	if (!access_ok(VERIFY_READ, addr, sizeof(struct pt_watch_regs)))
 		return -EIO;
 	/* Check the values. */
 	for (i = 0; i < current_cpu_data.watch_reg_use_cnt; i++) {
 		__get_user(lt[i], &addr->WATCH_STYLE.watchlo[i]);
 #ifdef CONFIG_32BIT
 		if (lt[i] & __UA_LIMIT)
 			return -EINVAL;
 #else
 		if (test_tsk_thread_flag(child, TIF_32BIT_ADDR)) {
 			if (lt[i] & 0xffffffff80000000UL)
 				return -EINVAL;
 		} else {
 			if (lt[i] & __UA_LIMIT)
 				return -EINVAL;
 		}
 #endif
 		__get_user(ht[i], &addr->WATCH_STYLE.watchhi[i]);
 		if (ht[i] & ~0xff8)
 			return -EINVAL;
 	}
 	/* Install them. */
 	for (i = 0; i < current_cpu_data.watch_reg_use_cnt; i++) {
 		if (lt[i] & 7)
 			watch_active = 1;
 		child->thread.watch.mips3264.watchlo[i] = lt[i];
 		/* Set the G bit. */
 		child->thread.watch.mips3264.watchhi[i] = ht[i];
 	}

 	if (watch_active)
 		set_tsk_thread_flag(child, TIF_LOAD_WATCH);
 	else
 		clear_tsk_thread_flag(child, TIF_LOAD_WATCH);

 	return 0;
 }

 long arch_ptrace(struct task_struct *child, long request,
 		 unsigned long addr, unsigned long data)
 {
 	int ret;
 	void __user *addrp = (void __user *) addr;
 	void __user *datavp = (void __user *) data;
 	unsigned long __user *datalp = (void __user *) data;

 	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: {
 		struct pt_regs *regs;
 		unsigned long tmp = 0;

 		regs = task_pt_regs(child);
 		ret = 0;  /* Default return value. */

 		switch (addr) {
 		case 0 ... 31:
 			tmp = regs->regs[addr];
 			break;
 		case FPR_BASE ... FPR_BASE + 31:
 			if (tsk_used_math(child)) {
 				fpureg_t *fregs = get_fpu_regs(child);

 #ifdef CONFIG_32BIT
 				/*
 				 * The odd registers are actually the high
 				 * order bits of the values stored in the even
 				 * registers - unless we're using r2k_switch.S.
 				 */
 				if (addr & 1)
 					tmp = (unsigned long) (fregs[((addr & ~1) - 32)] >> 32);
 				else
 					tmp = (unsigned long) (fregs[(addr - 32)] & 0xffffffff);
 #endif
 #ifdef CONFIG_64BIT
 				tmp = fregs[addr - FPR_BASE];
 #endif
 			} else {
 				tmp = -1;	/* FP not yet used  */
 			}
 			break;
 		case PC:
 			tmp = regs->cp0_epc;
 			break;
 		case CAUSE:
 			tmp = regs->cp0_cause;
 			break;
 		case BADVADDR:
 			tmp = regs->cp0_badvaddr;
 			break;
 		case MMHI:
 			tmp = regs->hi;
 			break;
 		case MMLO:
 			tmp = regs->lo;
 			break;
 #ifdef CONFIG_CPU_HAS_SMARTMIPS
 		case ACX:
 			tmp = regs->acx;
 			break;
 #endif
 		case FPC_CSR:
 			tmp = child->thread.fpu.fcr31;
 			break;
 		case FPC_EIR: { /* implementation / version register */
 			unsigned int flags;
 #ifdef CONFIG_MIPS_MT_SMTC
 			unsigned long irqflags;
 			unsigned int mtflags;
 #endif /* CONFIG_MIPS_MT_SMTC */

 			preempt_disable();
 			if (!cpu_has_fpu) {
 				preempt_enable();
 				break;
 			}

 #ifdef CONFIG_MIPS_MT_SMTC
 			/* Read-modify-write of Status must be atomic */
 			local_irq_save(irqflags);
 			mtflags = dmt();
 #endif /* CONFIG_MIPS_MT_SMTC */
 			if (cpu_has_mipsmt) {
 				unsigned int vpflags = dvpe();
 				flags = read_c0_status();
 				__enable_fpu();
 				__asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
 				write_c0_status(flags);
 				evpe(vpflags);
 			} else {
 				flags = read_c0_status();
 				__enable_fpu();
 				__asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
 				write_c0_status(flags);
 			}
 #ifdef CONFIG_MIPS_MT_SMTC
 			emt(mtflags);
 			local_irq_restore(irqflags);
 #endif /* CONFIG_MIPS_MT_SMTC */
 			preempt_enable();
 			break;
 		}
 		case DSP_BASE ... DSP_BASE + 5: {
 			dspreg_t *dregs;

 			if (!cpu_has_dsp) {
 				tmp = 0;
 				ret = -EIO;
 				goto out;
 			}
 			dregs = __get_dsp_regs(child);
 			tmp = (unsigned long) (dregs[addr - DSP_BASE]);
 			break;
 		}
 		case DSP_CONTROL:
 			if (!cpu_has_dsp) {
 				tmp = 0;
 				ret = -EIO;
 				goto out;
 			}
 			tmp = child->thread.dsp.dspcontrol;
 			break;
 		default:
 			tmp = 0;
 			ret = -EIO;
 			goto out;
 		}
 		ret = put_user(tmp, datalp);
 		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: {
 		struct pt_regs *regs;
 		ret = 0;
 		regs = task_pt_regs(child);

 		switch (addr) {
 		case 0 ... 31:
 			regs->regs[addr] = data;
 			break;
 		case FPR_BASE ... FPR_BASE + 31: {
 			fpureg_t *fregs = get_fpu_regs(child);

 			if (!tsk_used_math(child)) {
 				/* FP not yet used  */
 				memset(&child->thread.fpu, ~0,
 				       sizeof(child->thread.fpu));
 				child->thread.fpu.fcr31 = 0;
 			}
 #ifdef CONFIG_32BIT
 			/*
 			 * The odd registers are actually the high order bits
 			 * of the values stored in the even registers - unless
 			 * we're using r2k_switch.S.
 			 */
 			if (addr & 1) {
 				fregs[(addr & ~1) - FPR_BASE] &= 0xffffffff;
 				fregs[(addr & ~1) - FPR_BASE] |= ((unsigned long long) data) << 32;
 			} else {
 				fregs[addr - FPR_BASE] &= ~0xffffffffLL;
 				fregs[addr - FPR_BASE] |= data;
 			}
 #endif
 #ifdef CONFIG_64BIT
 			fregs[addr - FPR_BASE] = data;
 #endif
 			break;
 		}
 		case PC:
 			regs->cp0_epc = data;
 			break;
 		case MMHI:
 			regs->hi = data;
 			break;
 		case MMLO:
 			regs->lo = data;
 			break;
 #ifdef CONFIG_CPU_HAS_SMARTMIPS
 		case ACX:
 			regs->acx = data;
 			break;
 #endif
 		case FPC_CSR:
 			child->thread.fpu.fcr31 = data;
 			break;
 		case DSP_BASE ... DSP_BASE + 5: {
 			dspreg_t *dregs;

 			if (!cpu_has_dsp) {
 				ret = -EIO;
 				break;
 			}

 			dregs = __get_dsp_regs(child);
 			dregs[addr - DSP_BASE] = data;
 			break;
 		}
 		case DSP_CONTROL:
 			if (!cpu_has_dsp) {
 				ret = -EIO;
 				break;
 			}
 			child->thread.dsp.dspcontrol = data;
 			break;
 		default:
 			/* The rest are not allowed. */
 			ret = -EIO;
 			break;
 		}
 		break;
 		}

 	case PTRACE_GETREGS:
 		ret = ptrace_getregs(child, datavp);
 		break;

 	case PTRACE_SETREGS:
 		ret = ptrace_setregs(child, datavp);
 		break;

 	case PTRACE_GETFPREGS:
 		ret = ptrace_getfpregs(child, datavp);
 		break;

 	case PTRACE_SETFPREGS:
 		ret = ptrace_setfpregs(child, datavp);
 		break;

 	case PTRACE_GET_THREAD_AREA:
 		ret = put_user(task_thread_info(child)->tp_value, datalp);
 		break;

 	case PTRACE_GET_WATCH_REGS:
 		ret = ptrace_get_watch_regs(child, addrp);
 		break;

 	case PTRACE_SET_WATCH_REGS:
 		ret = ptrace_set_watch_regs(child, addrp);
 		break;

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

 static inline int audit_arch(void)
 {
 	int arch = EM_MIPS;
 #ifdef CONFIG_64BIT
 	arch |=	 __AUDIT_ARCH_64BIT;
 #endif
 #if defined(__LITTLE_ENDIAN)
 	arch |=	 __AUDIT_ARCH_LE;
 #endif
 	return arch;
 }

 /*
  * Notification of system call entry/exit
  * - triggered by current->work.syscall_trace
  */
 asmlinkage void syscall_trace_enter(struct pt_regs *regs)
 {
 	user_exit();

 	/* do the secure computing check first */
 	secure_computing_strict(regs->regs[2]);

 	if (!(current->ptrace & PT_PTRACED))
 		goto out;

 	if (!test_thread_flag(TIF_SYSCALL_TRACE))
 		goto out;

 	/* 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;
 	}

 out:
 	audit_syscall_entry(audit_arch(), regs->regs[2],
 			    regs->regs[4], regs->regs[5],
 			    regs->regs[6], regs->regs[7]);
 }

 /*
  * Notification of system call entry/exit
  * - triggered by current->work.syscall_trace
  */
 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
 {
         /*
 	 * We may come here right after calling schedule_user()
 	 * or do_notify_resume(), in which case we can be in RCU
 	 * user mode.
 	 */
 	user_exit();

 	audit_syscall_exit(regs);

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

 	if (!test_thread_flag(TIF_SYSCALL_TRACE))
 		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;
 	}

 	user_enter();
 }
	/*
	* 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.
	*
	* Copyright (C) 1992 Ross Biro
	* Copyright (C) Linus Torvalds
	* Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
	* Copyright (C) 1996 David S. Miller
	* Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
	* Copyright (C) 1999 MIPS Technologies, Inc.
	* Copyright (C) 2000 Ulf Carlsson
	*
	* At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
	* binaries.
	*/
	#include <linux/compiler.h>
	#include <linux/context_tracking.h>
	#include <linux/kernel.h>
	#include <linux/sched.h>
	#include <linux/mm.h>
	#include <linux/errno.h>
	#include <linux/ptrace.h>
	#include <linux/smp.h>
	#include <linux/user.h>
	#include <linux/security.h>
	#include <linux/audit.h>
	#include <linux/seccomp.h>

	#include <asm/byteorder.h>
	#include <asm/cpu.h>
	#include <asm/dsp.h>
	#include <asm/fpu.h>
	#include <asm/mipsregs.h>
	#include <asm/mipsmtregs.h>
	#include <asm/pgtable.h>
	#include <asm/page.h>
	#include <asm/uaccess.h>
	#include <asm/bootinfo.h>
	#include <asm/reg.h>

	/*
	* Called by kernel/ptrace.c when detaching..
	*
	* Make sure single step bits etc are not set.
	*/
	void ptrace_disable(struct task_struct *child)
	{
	/* Don't load the watchpoint registers for the ex-child. */
	clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
	}

	/*
	* Read a general register set. We always use the 64-bit format, even
	* for 32-bit kernels and for 32-bit processes on a 64-bit kernel.
	* Registers are sign extended to fill the available space.
	*/
	int ptrace_getregs(struct task_struct child, __s64 __user data)
	{
	struct pt_regs *regs;
	int i;

	if (!access_ok(VERIFY_WRITE, data, 38 * 8))
	return -EIO;

	regs = task_pt_regs(child);

	for (i = 0; i < 32; i++)
	__put_user((long)regs->regs[i], data + i);
	__put_user((long)regs->lo, data + EF_LO - EF_R0);
	__put_user((long)regs->hi, data + EF_HI - EF_R0);
	__put_user((long)regs->cp0_epc, data + EF_CP0_EPC - EF_R0);
	__put_user((long)regs->cp0_badvaddr, data + EF_CP0_BADVADDR - EF_R0);
	__put_user((long)regs->cp0_status, data + EF_CP0_STATUS - EF_R0);
	__put_user((long)regs->cp0_cause, data + EF_CP0_CAUSE - EF_R0);

	return 0;
	}

	/*
	* Write a general register set. As for PTRACE_GETREGS, we always use
	* the 64-bit format. On a 32-bit kernel only the lower order half
	* (according to endianness) will be used.
	*/
	int ptrace_setregs(struct task_struct child, __s64 __user data)
	{
	struct pt_regs *regs;
	int i;

	if (!access_ok(VERIFY_READ, data, 38 * 8))
	return -EIO;

	regs = task_pt_regs(child);

	for (i = 0; i < 32; i++)
	__get_user(regs->regs[i], data + i);
	__get_user(regs->lo, data + EF_LO - EF_R0);
	__get_user(regs->hi, data + EF_HI - EF_R0);
	__get_user(regs->cp0_epc, data + EF_CP0_EPC - EF_R0);

	/* badvaddr, status, and cause may not be written. */

	return 0;
	}

	int ptrace_getfpregs(struct task_struct child, __u32 __user data)
	{
	int i;
	unsigned int tmp;

	if (!access_ok(VERIFY_WRITE, data, 33 * 8))
	return -EIO;

	if (tsk_used_math(child)) {
	fpureg_t *fregs = get_fpu_regs(child);
	for (i = 0; i < 32; i++)
	__put_user(fregs[i], i + (__u64 __user *) data);
	} else {
	for (i = 0; i < 32; i++)
	__put_user((__u64) -1, i + (__u64 __user *) data);
	}

	__put_user(child->thread.fpu.fcr31, data + 64);

	preempt_disable();
	if (cpu_has_fpu) {
	unsigned int flags;

	if (cpu_has_mipsmt) {
	unsigned int vpflags = dvpe();
	flags = read_c0_status();
	__enable_fpu();
	__asm__ __volatile__("cfc1\t%0,$0" : "=r" (tmp));
	write_c0_status(flags);
	evpe(vpflags);
	} else {
	flags = read_c0_status();
	__enable_fpu();
	__asm__ __volatile__("cfc1\t%0,$0" : "=r" (tmp));
	write_c0_status(flags);
	}
	} else {
	tmp = 0;
	}
	preempt_enable();
	__put_user(tmp, data + 65);

	return 0;
	}

	int ptrace_setfpregs(struct task_struct child, __u32 __user data)
	{
	fpureg_t *fregs;
	int i;

	if (!access_ok(VERIFY_READ, data, 33 * 8))
	return -EIO;

	fregs = get_fpu_regs(child);

	for (i = 0; i < 32; i++)
	__get_user(fregs[i], i + (__u64 __user *) data);

	__get_user(child->thread.fpu.fcr31, data + 64);

	/* FIR may not be written. */

	return 0;
	}

	int ptrace_get_watch_regs(struct task_struct *child,
	struct pt_watch_regs __user *addr)
	{
	enum pt_watch_style style;
	int i;

	if (!cpu_has_watch \|\| current_cpu_data.watch_reg_use_cnt == 0)
	return -EIO;
	if (!access_ok(VERIFY_WRITE, addr, sizeof(struct pt_watch_regs)))
	return -EIO;

	#ifdef CONFIG_32BIT
	style = pt_watch_style_mips32;
	#define WATCH_STYLE mips32
	#else
	style = pt_watch_style_mips64;
	#define WATCH_STYLE mips64
	#endif

	__put_user(style, &addr->style);
	__put_user(current_cpu_data.watch_reg_use_cnt,
	&addr->WATCH_STYLE.num_valid);
	for (i = 0; i < current_cpu_data.watch_reg_use_cnt; i++) {
	__put_user(child->thread.watch.mips3264.watchlo[i],
	&addr->WATCH_STYLE.watchlo[i]);
	__put_user(child->thread.watch.mips3264.watchhi[i] & 0xfff,
	&addr->WATCH_STYLE.watchhi[i]);
	__put_user(current_cpu_data.watch_reg_masks[i],
	&addr->WATCH_STYLE.watch_masks[i]);
	}
	for (; i < 8; i++) {
	__put_user(0, &addr->WATCH_STYLE.watchlo[i]);
	__put_user(0, &addr->WATCH_STYLE.watchhi[i]);
	__put_user(0, &addr->WATCH_STYLE.watch_masks[i]);
	}

	return 0;
	}

	int ptrace_set_watch_regs(struct task_struct *child,
	struct pt_watch_regs __user *addr)
	{
	int i;
	int watch_active = 0;
	unsigned long lt[NUM_WATCH_REGS];
	u16 ht[NUM_WATCH_REGS];

	if (!cpu_has_watch \|\| current_cpu_data.watch_reg_use_cnt == 0)
	return -EIO;
	if (!access_ok(VERIFY_READ, addr, sizeof(struct pt_watch_regs)))
	return -EIO;
	/* Check the values. */
	for (i = 0; i < current_cpu_data.watch_reg_use_cnt; i++) {
	__get_user(lt[i], &addr->WATCH_STYLE.watchlo[i]);
	#ifdef CONFIG_32BIT
	if (lt[i] & __UA_LIMIT)
	return -EINVAL;
	#else
	if (test_tsk_thread_flag(child, TIF_32BIT_ADDR)) {
	if (lt[i] & 0xffffffff80000000UL)
	return -EINVAL;
	} else {
	if (lt[i] & __UA_LIMIT)
	return -EINVAL;
	}
	#endif
	__get_user(ht[i], &addr->WATCH_STYLE.watchhi[i]);
	if (ht[i] & ~0xff8)
	return -EINVAL;
	}
	/* Install them. */
	for (i = 0; i < current_cpu_data.watch_reg_use_cnt; i++) {
	if (lt[i] & 7)
	watch_active = 1;
	child->thread.watch.mips3264.watchlo[i] = lt[i];
	/* Set the G bit. */
	child->thread.watch.mips3264.watchhi[i] = ht[i];
	}

	if (watch_active)
	set_tsk_thread_flag(child, TIF_LOAD_WATCH);
	else
	clear_tsk_thread_flag(child, TIF_LOAD_WATCH);

	return 0;
	}

	long arch_ptrace(struct task_struct *child, long request,
	unsigned long addr, unsigned long data)
	{
	int ret;
	void __user addrp = (void __user ) addr;
	void __user datavp = (void __user ) data;
	unsigned long __user datalp = (void __user ) data;

	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: {
	struct pt_regs *regs;
	unsigned long tmp = 0;

	regs = task_pt_regs(child);
	ret = 0; /* Default return value. */

	switch (addr) {
	case 0 ... 31:
	tmp = regs->regs[addr];
	break;
	case FPR_BASE ... FPR_BASE + 31:
	if (tsk_used_math(child)) {
	fpureg_t *fregs = get_fpu_regs(child);

	#ifdef CONFIG_32BIT
	/*
	* The odd registers are actually the high
	* order bits of the values stored in the even
	* registers - unless we're using r2k_switch.S.
	*/
	if (addr & 1)
	tmp = (unsigned long) (fregs[((addr & ~1) - 32)] >> 32);
	else
	tmp = (unsigned long) (fregs[(addr - 32)] & 0xffffffff);
	#endif
	#ifdef CONFIG_64BIT
	tmp = fregs[addr - FPR_BASE];
	#endif
	} else {
	tmp = -1; /* FP not yet used */
	}
	break;
	case PC:
	tmp = regs->cp0_epc;
	break;
	case CAUSE:
	tmp = regs->cp0_cause;
	break;
	case BADVADDR:
	tmp = regs->cp0_badvaddr;
	break;
	case MMHI:
	tmp = regs->hi;
	break;
	case MMLO:
	tmp = regs->lo;
	break;
	#ifdef CONFIG_CPU_HAS_SMARTMIPS
	case ACX:
	tmp = regs->acx;
	break;
	#endif
	case FPC_CSR:
	tmp = child->thread.fpu.fcr31;
	break;
	case FPC_EIR: { /* implementation / version register */
	unsigned int flags;
	#ifdef CONFIG_MIPS_MT_SMTC
	unsigned long irqflags;
	unsigned int mtflags;
	#endif /* CONFIG_MIPS_MT_SMTC */

	preempt_disable();
	if (!cpu_has_fpu) {
	preempt_enable();
	break;
	}

	#ifdef CONFIG_MIPS_MT_SMTC
	/* Read-modify-write of Status must be atomic */
	local_irq_save(irqflags);
	mtflags = dmt();
	#endif /* CONFIG_MIPS_MT_SMTC */
	if (cpu_has_mipsmt) {
	unsigned int vpflags = dvpe();
	flags = read_c0_status();
	__enable_fpu();
	__asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
	write_c0_status(flags);
	evpe(vpflags);
	} else {
	flags = read_c0_status();
	__enable_fpu();
	__asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
	write_c0_status(flags);
	}
	#ifdef CONFIG_MIPS_MT_SMTC
	emt(mtflags);
	local_irq_restore(irqflags);
	#endif /* CONFIG_MIPS_MT_SMTC */
	preempt_enable();
	break;
	}
	case DSP_BASE ... DSP_BASE + 5: {
	dspreg_t *dregs;

	if (!cpu_has_dsp) {
	tmp = 0;
	ret = -EIO;
	goto out;
	}
	dregs = __get_dsp_regs(child);
	tmp = (unsigned long) (dregs[addr - DSP_BASE]);
	break;
	}
	case DSP_CONTROL:
	if (!cpu_has_dsp) {
	tmp = 0;
	ret = -EIO;
	goto out;
	}
	tmp = child->thread.dsp.dspcontrol;
	break;
	default:
	tmp = 0;
	ret = -EIO;
	goto out;
	}
	ret = put_user(tmp, datalp);
	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: {
	struct pt_regs *regs;
	ret = 0;
	regs = task_pt_regs(child);

	switch (addr) {
	case 0 ... 31:
	regs->regs[addr] = data;
	break;
	case FPR_BASE ... FPR_BASE + 31: {
	fpureg_t *fregs = get_fpu_regs(child);

	if (!tsk_used_math(child)) {
	/* FP not yet used */
	memset(&child->thread.fpu, ~0,
	sizeof(child->thread.fpu));
	child->thread.fpu.fcr31 = 0;
	}
	#ifdef CONFIG_32BIT
	/*
	* The odd registers are actually the high order bits
	* of the values stored in the even registers - unless
	* we're using r2k_switch.S.
	*/
	if (addr & 1) {
	fregs[(addr & ~1) - FPR_BASE] &= 0xffffffff;
	fregs[(addr & ~1) - FPR_BASE] \|= ((unsigned long long) data) << 32;
	} else {
	fregs[addr - FPR_BASE] &= ~0xffffffffLL;
	fregs[addr - FPR_BASE] \|= data;
	}
	#endif
	#ifdef CONFIG_64BIT
	fregs[addr - FPR_BASE] = data;
	#endif
	break;
	}
	case PC:
	regs->cp0_epc = data;
	break;
	case MMHI:
	regs->hi = data;
	break;
	case MMLO:
	regs->lo = data;
	break;
	#ifdef CONFIG_CPU_HAS_SMARTMIPS
	case ACX:
	regs->acx = data;
	break;
	#endif
	case FPC_CSR:
	child->thread.fpu.fcr31 = data;
	break;
	case DSP_BASE ... DSP_BASE + 5: {
	dspreg_t *dregs;

	if (!cpu_has_dsp) {
	ret = -EIO;
	break;
	}

	dregs = __get_dsp_regs(child);
	dregs[addr - DSP_BASE] = data;
	break;
	}
	case DSP_CONTROL:
	if (!cpu_has_dsp) {
	ret = -EIO;
	break;
	}
	child->thread.dsp.dspcontrol = data;
	break;
	default:
	/* The rest are not allowed. */
	ret = -EIO;
	break;
	}
	break;
	}

	case PTRACE_GETREGS:
	ret = ptrace_getregs(child, datavp);
	break;

	case PTRACE_SETREGS:
	ret = ptrace_setregs(child, datavp);
	break;

	case PTRACE_GETFPREGS:
	ret = ptrace_getfpregs(child, datavp);
	break;

	case PTRACE_SETFPREGS:
	ret = ptrace_setfpregs(child, datavp);
	break;

	case PTRACE_GET_THREAD_AREA:
	ret = put_user(task_thread_info(child)->tp_value, datalp);
	break;

	case PTRACE_GET_WATCH_REGS:
	ret = ptrace_get_watch_regs(child, addrp);
	break;

	case PTRACE_SET_WATCH_REGS:
	ret = ptrace_set_watch_regs(child, addrp);
	break;

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

	static inline int audit_arch(void)
	{
	int arch = EM_MIPS;
	#ifdef CONFIG_64BIT
	arch \|= __AUDIT_ARCH_64BIT;
	#endif
	#if defined(__LITTLE_ENDIAN)
	arch \|= __AUDIT_ARCH_LE;
	#endif
	return arch;
	}

	/*
	* Notification of system call entry/exit
	* - triggered by current->work.syscall_trace
	*/
	asmlinkage void syscall_trace_enter(struct pt_regs *regs)
	{
	user_exit();

	/* do the secure computing check first */
	secure_computing_strict(regs->regs[2]);

	if (!(current->ptrace & PT_PTRACED))
	goto out;

	if (!test_thread_flag(TIF_SYSCALL_TRACE))
	goto out;

	/* 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;
	}

	out:
	audit_syscall_entry(audit_arch(), regs->regs[2],
	regs->regs[4], regs->regs[5],
	regs->regs[6], regs->regs[7]);
	}

	/*
	* Notification of system call entry/exit
	* - triggered by current->work.syscall_trace
	*/
	asmlinkage void syscall_trace_leave(struct pt_regs *regs)
	{
	/*
	* We may come here right after calling schedule_user()
	* or do_notify_resume(), in which case we can be in RCU
	* user mode.
	*/
	user_exit();

	audit_syscall_exit(regs);

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

	if (!test_thread_flag(TIF_SYSCALL_TRACE))
	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;
	}

	user_enter();
	}