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

 /*
  * linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
  * these modifications are Copyright 2004-2010 Analog Devices Inc.
  *
  * Licensed under the GPL-2
  */

 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/smp.h>
 #include <linux/elf.h>
 #include <linux/errno.h>
 #include <linux/ptrace.h>
 #include <linux/user.h>
 #include <linux/regset.h>
 #include <linux/signal.h>
 #include <linux/tracehook.h>
 #include <linux/uaccess.h>

 #include <asm/page.h>
 #include <asm/pgtable.h>
 #include <asm/system.h>
 #include <asm/processor.h>
 #include <asm/asm-offsets.h>
 #include <asm/dma.h>
 #include <asm/fixed_code.h>
 #include <asm/cacheflush.h>
 #include <asm/mem_map.h>
 #include <asm/mmu_context.h>

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

 /*
  * Get contents of register REGNO in task TASK.
  */
 static inline long
 get_reg(struct task_struct *task, unsigned long regno,
 	unsigned long __user *datap)
 {
 	long tmp;
 	struct pt_regs *regs = task_pt_regs(task);

 	if (regno & 3 || regno > PT_LAST_PSEUDO)
 		return -EIO;

 	switch (regno) {
 	case PT_TEXT_ADDR:
 		tmp = task->mm->start_code;
 		break;
 	case PT_TEXT_END_ADDR:
 		tmp = task->mm->end_code;
 		break;
 	case PT_DATA_ADDR:
 		tmp = task->mm->start_data;
 		break;
 	case PT_USP:
 		tmp = task->thread.usp;
 		break;
 	default:
 		if (regno < sizeof(*regs)) {
 			void *reg_ptr = regs;
 			tmp = *(long *)(reg_ptr + regno);
 		} else
 			return -EIO;
 	}

 	return put_user(tmp, datap);
 }

 /*
  * Write contents of register REGNO in task TASK.
  */
 static inline int
 put_reg(struct task_struct *task, unsigned long regno, unsigned long data)
 {
 	struct pt_regs *regs = task_pt_regs(task);

 	if (regno & 3 || regno > PT_LAST_PSEUDO)
 		return -EIO;

 	switch (regno) {
 	case PT_PC:
 		/*********************************************************************/
 		/* At this point the kernel is most likely in exception.             */
 		/* The RETX register will be used to populate the pc of the process. */
 		/*********************************************************************/
 		regs->retx = data;
 		regs->pc = data;
 		break;
 	case PT_RETX:
 		break;		/* regs->retx = data; break; */
 	case PT_USP:
 		regs->usp = data;
 		task->thread.usp = data;
 		break;
 	case PT_SYSCFG:	/* don't let userspace screw with this */
 		if ((data & ~1) != 0x6)
 			pr_warning("ptrace: ignore syscfg write of %#lx\n", data);
 		break;		/* regs->syscfg = data; break; */
 	default:
 		if (regno < sizeof(*regs)) {
 			void *reg_offset = regs;
 			*(long *)(reg_offset + regno) = data;
 		}
 		/* Ignore writes to pseudo registers */
 	}

 	return 0;
 }

 /*
  * check that an address falls within the bounds of the target process's memory mappings
  */
 int
 is_user_addr_valid(struct task_struct *child, unsigned long start, unsigned long len)
 {
 	struct vm_area_struct *vma;
 	struct sram_list_struct *sraml;

 	/* overflow */
 	if (start + len < start)
 		return -EIO;

 	vma = find_vma(child->mm, start);
 	if (vma && start >= vma->vm_start && start + len <= vma->vm_end)
 			return 0;

 	for (sraml = child->mm->context.sram_list; sraml; sraml = sraml->next)
 		if (start >= (unsigned long)sraml->addr
 		    && start + len < (unsigned long)sraml->addr + sraml->length)
 			return 0;

 	if (start >= FIXED_CODE_START && start + len < FIXED_CODE_END)
 		return 0;

 #ifdef CONFIG_APP_STACK_L1
 	if (child->mm->context.l1_stack_save)
 		if (start >= (unsigned long)l1_stack_base &&
 			start + len < (unsigned long)l1_stack_base + l1_stack_len)
 			return 0;
 #endif

 	return -EIO;
 }

 /*
  * retrieve the contents of Blackfin userspace general registers
  */
 static int genregs_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);
 	int ret;

 	/* This sucks ... */
 	regs->usp = target->thread.usp;

 	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 				  regs, 0, sizeof(*regs));
 	if (ret < 0)
 		return ret;

 	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 					sizeof(*regs), -1);
 }

 /*
  * update the contents of the Blackfin userspace general registers
  */
 static int genregs_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 *regs = task_pt_regs(target);
 	int ret;

 	/* Don't let people set SYSCFG (it's at the end of pt_regs) */
 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 				 regs, 0, PT_SYSCFG);
 	if (ret < 0)
 		return ret;

 	/* This sucks ... */
 	target->thread.usp = regs->usp;
 	/* regs->retx = regs->pc; */

 	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
 					PT_SYSCFG, -1);
 }

 /*
  * Define the register sets available on the Blackfin under Linux
  */
 enum bfin_regset {
 	REGSET_GENERAL,
 };

 static const struct user_regset bfin_regsets[] = {
 	[REGSET_GENERAL] = {
 		.core_note_type = NT_PRSTATUS,
 		.n              = sizeof(struct pt_regs) / sizeof(long),
 		.size           = sizeof(long),
 		.align          = sizeof(long),
 		.get            = genregs_get,
 		.set            = genregs_set,
 	},
 };

 static const struct user_regset_view user_bfin_native_view = {
 	.name      = "Blackfin",
 	.e_machine = EM_BLACKFIN,
 	.regsets   = bfin_regsets,
 	.n         = ARRAY_SIZE(bfin_regsets),
 };

 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 {
 	return &user_bfin_native_view;
 }

 void user_enable_single_step(struct task_struct *child)
 {
 	struct pt_regs *regs = task_pt_regs(child);
 	regs->syscfg |= SYSCFG_SSSTEP;

 	set_tsk_thread_flag(child, TIF_SINGLESTEP);
 }

 void user_disable_single_step(struct task_struct *child)
 {
 	struct pt_regs *regs = task_pt_regs(child);
 	regs->syscfg &= ~SYSCFG_SSSTEP;

 	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
 }

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

 	switch (request) {
 		/* when I and D space are separate, these will need to be fixed. */
 	case PTRACE_PEEKDATA:
 		pr_debug("ptrace: PEEKDATA\n");
 		/* fall through */
 	case PTRACE_PEEKTEXT:	/* read word at location addr. */
 		{
 			unsigned long tmp = 0;
 			int copied = 0, to_copy = sizeof(tmp);

 			ret = -EIO;
 			pr_debug("ptrace: PEEKTEXT at addr 0x%08lx + %i\n", addr, to_copy);
 			if (is_user_addr_valid(child, addr, to_copy) < 0)
 				break;
 			pr_debug("ptrace: user address is valid\n");

 			switch (bfin_mem_access_type(addr, to_copy)) {
 			case BFIN_MEM_ACCESS_CORE:
 			case BFIN_MEM_ACCESS_CORE_ONLY:
 				copied = access_process_vm(child, addr, &tmp,
 				                           to_copy, 0);
 				if (copied)
 					break;

 				/* hrm, why didn't that work ... maybe no mapping */
 				if (addr >= FIXED_CODE_START &&
 				    addr + to_copy <= FIXED_CODE_END) {
 					copy_from_user_page(0, 0, 0, &tmp, paddr, to_copy);
 					copied = to_copy;
 				} else if (addr >= BOOT_ROM_START) {
 					memcpy(&tmp, paddr, to_copy);
 					copied = to_copy;
 				}

 				break;
 			case BFIN_MEM_ACCESS_DMA:
 				if (safe_dma_memcpy(&tmp, paddr, to_copy))
 					copied = to_copy;
 				break;
 			case BFIN_MEM_ACCESS_ITEST:
 				if (isram_memcpy(&tmp, paddr, to_copy))
 					copied = to_copy;
 				break;
 			default:
 				copied = 0;
 				break;
 			}

 			pr_debug("ptrace: copied size %d [0x%08lx]\n", copied, tmp);
 			if (copied == to_copy)
 				ret = put_user(tmp, datap);
 			break;
 		}

 		/* when I and D space are separate, this will have to be fixed. */
 	case PTRACE_POKEDATA:
 		pr_debug("ptrace: PTRACE_PEEKDATA\n");
 		/* fall through */
 	case PTRACE_POKETEXT:	/* write the word at location addr. */
 		{
 			int copied = 0, to_copy = sizeof(data);

 			ret = -EIO;
 			pr_debug("ptrace: POKETEXT at addr 0x%08lx + %i bytes %lx\n",
 			         addr, to_copy, data);
 			if (is_user_addr_valid(child, addr, to_copy) < 0)
 				break;
 			pr_debug("ptrace: user address is valid\n");

 			switch (bfin_mem_access_type(addr, to_copy)) {
 			case BFIN_MEM_ACCESS_CORE:
 			case BFIN_MEM_ACCESS_CORE_ONLY:
 				copied = access_process_vm(child, addr, &data,
 				                           to_copy, 1);
 				break;
 			case BFIN_MEM_ACCESS_DMA:
 				if (safe_dma_memcpy(paddr, &data, to_copy))
 					copied = to_copy;
 				break;
 			case BFIN_MEM_ACCESS_ITEST:
 				if (isram_memcpy(paddr, &data, to_copy))
 					copied = to_copy;
 				break;
 			default:
 				copied = 0;
 				break;
 			}

 			pr_debug("ptrace: copied size %d\n", copied);
 			if (copied == to_copy)
 				ret = 0;
 			break;
 		}

 	case PTRACE_PEEKUSR:
 		switch (addr) {
 #ifdef CONFIG_BINFMT_ELF_FDPIC	/* backwards compat */
 		case PT_FDPIC_EXEC:
 			request = PTRACE_GETFDPIC;
 			addr = PTRACE_GETFDPIC_EXEC;
 			goto case_default;
 		case PT_FDPIC_INTERP:
 			request = PTRACE_GETFDPIC;
 			addr = PTRACE_GETFDPIC_INTERP;
 			goto case_default;
 #endif
 		default:
 			ret = get_reg(child, addr, datap);
 		}
 		pr_debug("ptrace: PEEKUSR reg %li with %#lx = %i\n", addr, data, ret);
 		break;

 	case PTRACE_POKEUSR:
 		ret = put_reg(child, addr, data);
 		pr_debug("ptrace: POKEUSR reg %li with %li = %i\n", addr, data, ret);
 		break;

 	case PTRACE_GETREGS:
 		pr_debug("ptrace: PTRACE_GETREGS\n");
 		return copy_regset_to_user(child, &user_bfin_native_view,
 					   REGSET_GENERAL,
 					   0, sizeof(struct pt_regs),
 					   datap);

 	case PTRACE_SETREGS:
 		pr_debug("ptrace: PTRACE_SETREGS\n");
 		return copy_regset_from_user(child, &user_bfin_native_view,
 					     REGSET_GENERAL,
 					     0, sizeof(struct pt_regs),
 					     datap);

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

 	return ret;
 }

 asmlinkage int syscall_trace_enter(struct pt_regs *regs)
 {
 	int ret = 0;

 	if (test_thread_flag(TIF_SYSCALL_TRACE))
 		ret = tracehook_report_syscall_entry(regs);

 	return ret;
 }

 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
 {
 	int step;

 	step = test_thread_flag(TIF_SINGLESTEP);
 	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
 		tracehook_report_syscall_exit(regs, step);
 }
	/*
	* linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
	* these modifications are Copyright 2004-2010 Analog Devices Inc.
	*
	* Licensed under the GPL-2
	*/

	#include <linux/kernel.h>
	#include <linux/sched.h>
	#include <linux/mm.h>
	#include <linux/smp.h>
	#include <linux/elf.h>
	#include <linux/errno.h>
	#include <linux/ptrace.h>
	#include <linux/user.h>
	#include <linux/regset.h>
	#include <linux/signal.h>
	#include <linux/tracehook.h>
	#include <linux/uaccess.h>

	#include <asm/page.h>
	#include <asm/pgtable.h>
	#include <asm/system.h>
	#include <asm/processor.h>
	#include <asm/asm-offsets.h>
	#include <asm/dma.h>
	#include <asm/fixed_code.h>
	#include <asm/cacheflush.h>
	#include <asm/mem_map.h>
	#include <asm/mmu_context.h>

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

	/*
	* Get contents of register REGNO in task TASK.
	*/
	static inline long
	get_reg(struct task_struct *task, unsigned long regno,
	unsigned long __user *datap)
	{
	long tmp;
	struct pt_regs *regs = task_pt_regs(task);

	if (regno & 3 \|\| regno > PT_LAST_PSEUDO)
	return -EIO;

	switch (regno) {
	case PT_TEXT_ADDR:
	tmp = task->mm->start_code;
	break;
	case PT_TEXT_END_ADDR:
	tmp = task->mm->end_code;
	break;
	case PT_DATA_ADDR:
	tmp = task->mm->start_data;
	break;
	case PT_USP:
	tmp = task->thread.usp;
	break;
	default:
	if (regno < sizeof(*regs)) {
	void *reg_ptr = regs;
	tmp = (long )(reg_ptr + regno);
	} else
	return -EIO;
	}

	return put_user(tmp, datap);
	}

	/*
	* Write contents of register REGNO in task TASK.
	*/
	static inline int
	put_reg(struct task_struct *task, unsigned long regno, unsigned long data)
	{
	struct pt_regs *regs = task_pt_regs(task);

	if (regno & 3 \|\| regno > PT_LAST_PSEUDO)
	return -EIO;

	switch (regno) {
	case PT_PC:
	/*********************************************************************/
	/* At this point the kernel is most likely in exception. */
	/* The RETX register will be used to populate the pc of the process. */
	/*********************************************************************/
	regs->retx = data;
	regs->pc = data;
	break;
	case PT_RETX:
	break; /* regs->retx = data; break; */
	case PT_USP:
	regs->usp = data;
	task->thread.usp = data;
	break;
	case PT_SYSCFG: /* don't let userspace screw with this */
	if ((data & ~1) != 0x6)
	pr_warning("ptrace: ignore syscfg write of %#lx\n", data);
	break; /* regs->syscfg = data; break; */
	default:
	if (regno < sizeof(*regs)) {
	void *reg_offset = regs;
	(long )(reg_offset + regno) = data;
	}
	/* Ignore writes to pseudo registers */
	}

	return 0;
	}

	/*
	* check that an address falls within the bounds of the target process's memory mappings
	*/
	int
	is_user_addr_valid(struct task_struct *child, unsigned long start, unsigned long len)
	{
	struct vm_area_struct *vma;
	struct sram_list_struct *sraml;

	/* overflow */
	if (start + len < start)
	return -EIO;

	vma = find_vma(child->mm, start);
	if (vma && start >= vma->vm_start && start + len <= vma->vm_end)
	return 0;

	for (sraml = child->mm->context.sram_list; sraml; sraml = sraml->next)
	if (start >= (unsigned long)sraml->addr
	&& start + len < (unsigned long)sraml->addr + sraml->length)
	return 0;

	if (start >= FIXED_CODE_START && start + len < FIXED_CODE_END)
	return 0;

	#ifdef CONFIG_APP_STACK_L1
	if (child->mm->context.l1_stack_save)
	if (start >= (unsigned long)l1_stack_base &&
	start + len < (unsigned long)l1_stack_base + l1_stack_len)
	return 0;
	#endif

	return -EIO;
	}

	/*
	* retrieve the contents of Blackfin userspace general registers
	*/
	static int genregs_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);
	int ret;

	/* This sucks ... */
	regs->usp = target->thread.usp;

	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
	regs, 0, sizeof(*regs));
	if (ret < 0)
	return ret;

	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
	sizeof(*regs), -1);
	}

	/*
	* update the contents of the Blackfin userspace general registers
	*/
	static int genregs_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 *regs = task_pt_regs(target);
	int ret;

	/* Don't let people set SYSCFG (it's at the end of pt_regs) */
	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
	regs, 0, PT_SYSCFG);
	if (ret < 0)
	return ret;

	/* This sucks ... */
	target->thread.usp = regs->usp;
	/* regs->retx = regs->pc; */

	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
	PT_SYSCFG, -1);
	}

	/*
	* Define the register sets available on the Blackfin under Linux
	*/
	enum bfin_regset {
	REGSET_GENERAL,
	};

	static const struct user_regset bfin_regsets[] = {
	[REGSET_GENERAL] = {
	.core_note_type = NT_PRSTATUS,
	.n = sizeof(struct pt_regs) / sizeof(long),
	.size = sizeof(long),
	.align = sizeof(long),
	.get = genregs_get,
	.set = genregs_set,
	},
	};

	static const struct user_regset_view user_bfin_native_view = {
	.name = "Blackfin",
	.e_machine = EM_BLACKFIN,
	.regsets = bfin_regsets,
	.n = ARRAY_SIZE(bfin_regsets),
	};

	const struct user_regset_view task_user_regset_view(struct task_struct task)
	{
	return &user_bfin_native_view;
	}

	void user_enable_single_step(struct task_struct *child)
	{
	struct pt_regs *regs = task_pt_regs(child);
	regs->syscfg \|= SYSCFG_SSSTEP;

	set_tsk_thread_flag(child, TIF_SINGLESTEP);
	}

	void user_disable_single_step(struct task_struct *child)
	{
	struct pt_regs *regs = task_pt_regs(child);
	regs->syscfg &= ~SYSCFG_SSSTEP;

	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
	}

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

	switch (request) {
	/* when I and D space are separate, these will need to be fixed. */
	case PTRACE_PEEKDATA:
	pr_debug("ptrace: PEEKDATA\n");
	/* fall through */
	case PTRACE_PEEKTEXT: /* read word at location addr. */
	{
	unsigned long tmp = 0;
	int copied = 0, to_copy = sizeof(tmp);

	ret = -EIO;
	pr_debug("ptrace: PEEKTEXT at addr 0x%08lx + %i\n", addr, to_copy);
	if (is_user_addr_valid(child, addr, to_copy) < 0)
	break;
	pr_debug("ptrace: user address is valid\n");

	switch (bfin_mem_access_type(addr, to_copy)) {
	case BFIN_MEM_ACCESS_CORE:
	case BFIN_MEM_ACCESS_CORE_ONLY:
	copied = access_process_vm(child, addr, &tmp,
	to_copy, 0);
	if (copied)
	break;

	/* hrm, why didn't that work ... maybe no mapping */
	if (addr >= FIXED_CODE_START &&
	addr + to_copy <= FIXED_CODE_END) {
	copy_from_user_page(0, 0, 0, &tmp, paddr, to_copy);
	copied = to_copy;
	} else if (addr >= BOOT_ROM_START) {
	memcpy(&tmp, paddr, to_copy);
	copied = to_copy;
	}

	break;
	case BFIN_MEM_ACCESS_DMA:
	if (safe_dma_memcpy(&tmp, paddr, to_copy))
	copied = to_copy;
	break;
	case BFIN_MEM_ACCESS_ITEST:
	if (isram_memcpy(&tmp, paddr, to_copy))
	copied = to_copy;
	break;
	default:
	copied = 0;
	break;
	}

	pr_debug("ptrace: copied size %d [0x%08lx]\n", copied, tmp);
	if (copied == to_copy)
	ret = put_user(tmp, datap);
	break;
	}

	/* when I and D space are separate, this will have to be fixed. */
	case PTRACE_POKEDATA:
	pr_debug("ptrace: PTRACE_PEEKDATA\n");
	/* fall through */
	case PTRACE_POKETEXT: /* write the word at location addr. */
	{
	int copied = 0, to_copy = sizeof(data);

	ret = -EIO;
	pr_debug("ptrace: POKETEXT at addr 0x%08lx + %i bytes %lx\n",
	addr, to_copy, data);
	if (is_user_addr_valid(child, addr, to_copy) < 0)
	break;
	pr_debug("ptrace: user address is valid\n");

	switch (bfin_mem_access_type(addr, to_copy)) {
	case BFIN_MEM_ACCESS_CORE:
	case BFIN_MEM_ACCESS_CORE_ONLY:
	copied = access_process_vm(child, addr, &data,
	to_copy, 1);
	break;
	case BFIN_MEM_ACCESS_DMA:
	if (safe_dma_memcpy(paddr, &data, to_copy))
	copied = to_copy;
	break;
	case BFIN_MEM_ACCESS_ITEST:
	if (isram_memcpy(paddr, &data, to_copy))
	copied = to_copy;
	break;
	default:
	copied = 0;
	break;
	}

	pr_debug("ptrace: copied size %d\n", copied);
	if (copied == to_copy)
	ret = 0;
	break;
	}

	case PTRACE_PEEKUSR:
	switch (addr) {
	#ifdef CONFIG_BINFMT_ELF_FDPIC /* backwards compat */
	case PT_FDPIC_EXEC:
	request = PTRACE_GETFDPIC;
	addr = PTRACE_GETFDPIC_EXEC;
	goto case_default;
	case PT_FDPIC_INTERP:
	request = PTRACE_GETFDPIC;
	addr = PTRACE_GETFDPIC_INTERP;
	goto case_default;
	#endif
	default:
	ret = get_reg(child, addr, datap);
	}
	pr_debug("ptrace: PEEKUSR reg %li with %#lx = %i\n", addr, data, ret);
	break;

	case PTRACE_POKEUSR:
	ret = put_reg(child, addr, data);
	pr_debug("ptrace: POKEUSR reg %li with %li = %i\n", addr, data, ret);
	break;

	case PTRACE_GETREGS:
	pr_debug("ptrace: PTRACE_GETREGS\n");
	return copy_regset_to_user(child, &user_bfin_native_view,
	REGSET_GENERAL,
	0, sizeof(struct pt_regs),
	datap);

	case PTRACE_SETREGS:
	pr_debug("ptrace: PTRACE_SETREGS\n");
	return copy_regset_from_user(child, &user_bfin_native_view,
	REGSET_GENERAL,
	0, sizeof(struct pt_regs),
	datap);

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

	return ret;
	}

	asmlinkage int syscall_trace_enter(struct pt_regs *regs)
	{
	int ret = 0;

	if (test_thread_flag(TIF_SYSCALL_TRACE))
	ret = tracehook_report_syscall_entry(regs);

	return ret;
	}

	asmlinkage void syscall_trace_leave(struct pt_regs *regs)
	{
	int step;

	step = test_thread_flag(TIF_SINGLESTEP);
	if (step \|\| test_thread_flag(TIF_SYSCALL_TRACE))
	tracehook_report_syscall_exit(regs, step);
	}