arch/mips/kernel/ptrace.c - arm/linux-arm64-legacy - 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/elf.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/errno.h>
 #include <linux/ptrace.h>
 #include <linux/regset.h>
 #include <linux/smp.h>
 #include <linux/user.h>
 #include <linux/security.h>
 #include <linux/tracehook.h>
 #include <linux/audit.h>
 #include <linux/seccomp.h>
 #include <linux/ftrace.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/syscall.h>
 #include <asm/uaccess.h>
 #include <asm/bootinfo.h>
 #include <asm/reg.h>

 #define CREATE_TRACE_POINTS
 #include <trace/events/syscalls.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;

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

 	if (tsk_used_math(child)) {
 		union fpureg *fregs = get_fpu_regs(child);
 		for (i = 0; i < 32; i++)
 			__put_user(get_fpr64(&fregs[i], 0),
 				   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);
 	__put_user(current_cpu_data.fpu_id, data + 65);

 	return 0;
 }

 int ptrace_setfpregs(struct task_struct *child, __u32 __user *data)
 {
 	union fpureg *fregs;
 	u64 fpr_val;
 	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(fpr_val, i + (__u64 __user *)data);
 		set_fpr64(&fregs[i], 0, fpr_val);
 	}

 	__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 || boot_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(boot_cpu_data.watch_reg_use_cnt,
 		   &addr->WATCH_STYLE.num_valid);
 	for (i = 0; i < boot_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(boot_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 || boot_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 < boot_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 < boot_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;
 }

 /* regset get/set implementations */

 static int gpr_get(struct task_struct *target,
 		   const struct user_regset *regset,
 		   unsigned int pos, unsigned int count,
 		   void *kbuf, void __user *ubuf)
 {
 	struct pt_regs *regs = task_pt_regs(target);

 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 				   regs, 0, sizeof(*regs));
 }

 static int gpr_set(struct task_struct *target,
 		   const struct user_regset *regset,
 		   unsigned int pos, unsigned int count,
 		   const void *kbuf, const void __user *ubuf)
 {
 	struct pt_regs newregs;
 	int ret;

 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 				 &newregs,
 				 0, sizeof(newregs));
 	if (ret)
 		return ret;

 	*task_pt_regs(target) = newregs;

 	return 0;
 }

 static int fpr_get(struct task_struct *target,
 		   const struct user_regset *regset,
 		   unsigned int pos, unsigned int count,
 		   void *kbuf, void __user *ubuf)
 {
 	unsigned i;
 	int err;
 	u64 fpr_val;

 	/* XXX fcr31  */

 	if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
 		return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 					   &target->thread.fpu,
 					   0, sizeof(elf_fpregset_t));

 	for (i = 0; i < NUM_FPU_REGS; i++) {
 		fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
 		err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 					  &fpr_val, i * sizeof(elf_fpreg_t),
 					  (i + 1) * sizeof(elf_fpreg_t));
 		if (err)
 			return err;
 	}

 	return 0;
 }

 static int fpr_set(struct task_struct *target,
 		   const struct user_regset *regset,
 		   unsigned int pos, unsigned int count,
 		   const void *kbuf, const void __user *ubuf)
 {
 	unsigned i;
 	int err;
 	u64 fpr_val;

 	/* XXX fcr31  */

 	if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
 		return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 					  &target->thread.fpu,
 					  0, sizeof(elf_fpregset_t));

 	for (i = 0; i < NUM_FPU_REGS; i++) {
 		err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 					 &fpr_val, i * sizeof(elf_fpreg_t),
 					 (i + 1) * sizeof(elf_fpreg_t));
 		if (err)
 			return err;
 		set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
 	}

 	return 0;
 }

 enum mips_regset {
 	REGSET_GPR,
 	REGSET_FPR,
 };

 static const struct user_regset mips_regsets[] = {
 	[REGSET_GPR] = {
 		.core_note_type	= NT_PRSTATUS,
 		.n		= ELF_NGREG,
 		.size		= sizeof(unsigned int),
 		.align		= sizeof(unsigned int),
 		.get		= gpr_get,
 		.set		= gpr_set,
 	},
 	[REGSET_FPR] = {
 		.core_note_type	= NT_PRFPREG,
 		.n		= ELF_NFPREG,
 		.size		= sizeof(elf_fpreg_t),
 		.align		= sizeof(elf_fpreg_t),
 		.get		= fpr_get,
 		.set		= fpr_set,
 	},
 };

 static const struct user_regset_view user_mips_view = {
 	.name		= "mips",
 	.e_machine	= ELF_ARCH,
 	.ei_osabi	= ELF_OSABI,
 	.regsets	= mips_regsets,
 	.n		= ARRAY_SIZE(mips_regsets),
 };

 static const struct user_regset mips64_regsets[] = {
 	[REGSET_GPR] = {
 		.core_note_type	= NT_PRSTATUS,
 		.n		= ELF_NGREG,
 		.size		= sizeof(unsigned long),
 		.align		= sizeof(unsigned long),
 		.get		= gpr_get,
 		.set		= gpr_set,
 	},
 	[REGSET_FPR] = {
 		.core_note_type	= NT_PRFPREG,
 		.n		= ELF_NFPREG,
 		.size		= sizeof(elf_fpreg_t),
 		.align		= sizeof(elf_fpreg_t),
 		.get		= fpr_get,
 		.set		= fpr_set,
 	},
 };

 static const struct user_regset_view user_mips64_view = {
 	.name		= "mips",
 	.e_machine	= ELF_ARCH,
 	.ei_osabi	= ELF_OSABI,
 	.regsets	= mips64_regsets,
 	.n		= ARRAY_SIZE(mips_regsets),
 };

 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 {
 #ifdef CONFIG_32BIT
 	return &user_mips_view;
 #endif

 #ifdef CONFIG_MIPS32_O32
 		if (test_thread_flag(TIF_32BIT_REGS))
 			return &user_mips_view;
 #endif

 	return &user_mips64_view;
 }

 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;
 		union fpureg *fregs;
 		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)) {
 				/* FP not yet used */
 				tmp = -1;
 				break;
 			}
 			fregs = get_fpu_regs(child);

 #ifdef CONFIG_32BIT
 			if (test_thread_flag(TIF_32BIT_FPREGS)) {
 				/*
 				 * The odd registers are actually the high
 				 * order bits of the values stored in the even
 				 * registers - unless we're using r2k_switch.S.
 				 */
 				tmp = get_fpr32(&fregs[(addr & ~1) - FPR_BASE],
 						addr & 1);
 				break;
 			}
 #endif
 			tmp = get_fpr32(&fregs[addr - FPR_BASE], 0);
 			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 */
 			tmp = current_cpu_data.fpu_id;
 			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: {
 			union fpureg *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
 			if (test_thread_flag(TIF_32BIT_FPREGS)) {
 				/*
 				 * The odd registers are actually the high
 				 * order bits of the values stored in the even
 				 * registers - unless we're using r2k_switch.S.
 				 */
 				set_fpr32(&fregs[(addr & ~1) - FPR_BASE],
 					  addr & 1, data);
 				break;
 			}
 #endif
 			set_fpr64(&fregs[addr - FPR_BASE], 0, data);
 			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;
 }

 /*
  * Notification of system call entry/exit
  * - triggered by current->work.syscall_trace
  */
 asmlinkage long syscall_trace_enter(struct pt_regs *regs, long syscall)
 {
 	long ret = 0;
 	user_exit();

 	if (secure_computing(syscall) == -1)
 		return -1;

 	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 	    tracehook_report_syscall_entry(regs))
 		ret = -1;

 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 		trace_sys_enter(regs, regs->regs[2]);

 	audit_syscall_entry(syscall_get_arch(),
 			    syscall,
 			    regs->regs[4], regs->regs[5],
 			    regs->regs[6], regs->regs[7]);
 	return syscall;
 }

 /*
  * 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 (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 		trace_sys_exit(regs, regs->regs[2]);

 	if (test_thread_flag(TIF_SYSCALL_TRACE))
 		tracehook_report_syscall_exit(regs, 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/elf.h>
	#include <linux/kernel.h>
	#include <linux/sched.h>
	#include <linux/mm.h>
	#include <linux/errno.h>
	#include <linux/ptrace.h>
	#include <linux/regset.h>
	#include <linux/smp.h>
	#include <linux/user.h>
	#include <linux/security.h>
	#include <linux/tracehook.h>
	#include <linux/audit.h>
	#include <linux/seccomp.h>
	#include <linux/ftrace.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/syscall.h>
	#include <asm/uaccess.h>
	#include <asm/bootinfo.h>
	#include <asm/reg.h>

	#define CREATE_TRACE_POINTS
	#include <trace/events/syscalls.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;

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

	if (tsk_used_math(child)) {
	union fpureg *fregs = get_fpu_regs(child);
	for (i = 0; i < 32; i++)
	__put_user(get_fpr64(&fregs[i], 0),
	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);
	__put_user(current_cpu_data.fpu_id, data + 65);

	return 0;
	}

	int ptrace_setfpregs(struct task_struct child, __u32 __user data)
	{
	union fpureg *fregs;
	u64 fpr_val;
	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(fpr_val, i + (__u64 __user *)data);
	set_fpr64(&fregs[i], 0, fpr_val);
	}

	__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 \|\| boot_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(boot_cpu_data.watch_reg_use_cnt,
	&addr->WATCH_STYLE.num_valid);
	for (i = 0; i < boot_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(boot_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 \|\| boot_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 < boot_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 < boot_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;
	}

	/* regset get/set implementations */

	static int gpr_get(struct task_struct *target,
	const struct user_regset *regset,
	unsigned int pos, unsigned int count,
	void kbuf, void __user ubuf)
	{
	struct pt_regs *regs = task_pt_regs(target);

	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
	regs, 0, sizeof(*regs));
	}

	static int gpr_set(struct task_struct *target,
	const struct user_regset *regset,
	unsigned int pos, unsigned int count,
	const void kbuf, const void __user ubuf)
	{
	struct pt_regs newregs;
	int ret;

	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
	&newregs,
	0, sizeof(newregs));
	if (ret)
	return ret;

	*task_pt_regs(target) = newregs;

	return 0;
	}

	static int fpr_get(struct task_struct *target,
	const struct user_regset *regset,
	unsigned int pos, unsigned int count,
	void kbuf, void __user ubuf)
	{
	unsigned i;
	int err;
	u64 fpr_val;

	/* XXX fcr31 */

	if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
	&target->thread.fpu,
	0, sizeof(elf_fpregset_t));

	for (i = 0; i < NUM_FPU_REGS; i++) {
	fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
	err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
	&fpr_val, i * sizeof(elf_fpreg_t),
	(i + 1) * sizeof(elf_fpreg_t));
	if (err)
	return err;
	}

	return 0;
	}

	static int fpr_set(struct task_struct *target,
	const struct user_regset *regset,
	unsigned int pos, unsigned int count,
	const void kbuf, const void __user ubuf)
	{
	unsigned i;
	int err;
	u64 fpr_val;

	/* XXX fcr31 */

	if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
	return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
	&target->thread.fpu,
	0, sizeof(elf_fpregset_t));

	for (i = 0; i < NUM_FPU_REGS; i++) {
	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
	&fpr_val, i * sizeof(elf_fpreg_t),
	(i + 1) * sizeof(elf_fpreg_t));
	if (err)
	return err;
	set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
	}

	return 0;
	}

	enum mips_regset {
	REGSET_GPR,
	REGSET_FPR,
	};

	static const struct user_regset mips_regsets[] = {
	[REGSET_GPR] = {
	.core_note_type = NT_PRSTATUS,
	.n = ELF_NGREG,
	.size = sizeof(unsigned int),
	.align = sizeof(unsigned int),
	.get = gpr_get,
	.set = gpr_set,
	},
	[REGSET_FPR] = {
	.core_note_type = NT_PRFPREG,
	.n = ELF_NFPREG,
	.size = sizeof(elf_fpreg_t),
	.align = sizeof(elf_fpreg_t),
	.get = fpr_get,
	.set = fpr_set,
	},
	};

	static const struct user_regset_view user_mips_view = {
	.name = "mips",
	.e_machine = ELF_ARCH,
	.ei_osabi = ELF_OSABI,
	.regsets = mips_regsets,
	.n = ARRAY_SIZE(mips_regsets),
	};

	static const struct user_regset mips64_regsets[] = {
	[REGSET_GPR] = {
	.core_note_type = NT_PRSTATUS,
	.n = ELF_NGREG,
	.size = sizeof(unsigned long),
	.align = sizeof(unsigned long),
	.get = gpr_get,
	.set = gpr_set,
	},
	[REGSET_FPR] = {
	.core_note_type = NT_PRFPREG,
	.n = ELF_NFPREG,
	.size = sizeof(elf_fpreg_t),
	.align = sizeof(elf_fpreg_t),
	.get = fpr_get,
	.set = fpr_set,
	},
	};

	static const struct user_regset_view user_mips64_view = {
	.name = "mips",
	.e_machine = ELF_ARCH,
	.ei_osabi = ELF_OSABI,
	.regsets = mips64_regsets,
	.n = ARRAY_SIZE(mips_regsets),
	};

	const struct user_regset_view task_user_regset_view(struct task_struct task)
	{
	#ifdef CONFIG_32BIT
	return &user_mips_view;
	#endif

	#ifdef CONFIG_MIPS32_O32
	if (test_thread_flag(TIF_32BIT_REGS))
	return &user_mips_view;
	#endif

	return &user_mips64_view;
	}

	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;
	union fpureg *fregs;
	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)) {
	/* FP not yet used */
	tmp = -1;
	break;
	}
	fregs = get_fpu_regs(child);

	#ifdef CONFIG_32BIT
	if (test_thread_flag(TIF_32BIT_FPREGS)) {
	/*
	* The odd registers are actually the high
	* order bits of the values stored in the even
	* registers - unless we're using r2k_switch.S.
	*/
	tmp = get_fpr32(&fregs[(addr & ~1) - FPR_BASE],
	addr & 1);
	break;
	}
	#endif
	tmp = get_fpr32(&fregs[addr - FPR_BASE], 0);
	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 */
	tmp = current_cpu_data.fpu_id;
	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: {
	union fpureg *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
	if (test_thread_flag(TIF_32BIT_FPREGS)) {
	/*
	* The odd registers are actually the high
	* order bits of the values stored in the even
	* registers - unless we're using r2k_switch.S.
	*/
	set_fpr32(&fregs[(addr & ~1) - FPR_BASE],
	addr & 1, data);
	break;
	}
	#endif
	set_fpr64(&fregs[addr - FPR_BASE], 0, data);
	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;
	}

	/*
	* Notification of system call entry/exit
	* - triggered by current->work.syscall_trace
	*/
	asmlinkage long syscall_trace_enter(struct pt_regs *regs, long syscall)
	{
	long ret = 0;
	user_exit();

	if (secure_computing(syscall) == -1)
	return -1;

	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
	tracehook_report_syscall_entry(regs))
	ret = -1;

	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
	trace_sys_enter(regs, regs->regs[2]);

	audit_syscall_entry(syscall_get_arch(),
	syscall,
	regs->regs[4], regs->regs[5],
	regs->regs[6], regs->regs[7]);
	return syscall;
	}

	/*
	* 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 (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
	trace_sys_exit(regs, regs->regs[2]);

	if (test_thread_flag(TIF_SYSCALL_TRACE))
	tracehook_report_syscall_exit(regs, 0);

	user_enter();
	}