path: root/arch/csky/kernel/ptrace.c

// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.

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

#include <asm/thread_info.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/asm-offsets.h>

#include <abi/regdef.h>

#define CREATE_TRACE_POINTS
#include <trace/events/syscalls.h>

/* sets the trace bits. */
#define TRACE_MODE_SI      (1 << 14)
#define TRACE_MODE_RUN     0
#define TRACE_MODE_MASK    ~(0x3 << 14)

/*
 * Make sure the single step bit is not set.
 */
static void singlestep_disable(struct task_struct *tsk)
{
	struct pt_regs *regs;

	regs = task_pt_regs(tsk);
	regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_RUN;

	/* Enable irq */
	regs->sr |= BIT(6);
}

static void singlestep_enable(struct task_struct *tsk)
{
	struct pt_regs *regs;

	regs = task_pt_regs(tsk);
	regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_SI;

	/* Disable irq */
	regs->sr &= ~BIT(6);
}

/*
 * Make sure the single step bit is set.
 */
void user_enable_single_step(struct task_struct *child)
{
	singlestep_enable(child);
}

void user_disable_single_step(struct task_struct *child)
{
	singlestep_disable(child);
}

enum csky_regset {
	REGSET_GPR,
	REGSET_FPR,
};

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;

	regs = task_pt_regs(target);

	/* Abiv1 regs->tls is fake and we need sync here. */
	regs->tls = task_thread_info(target)->tp_value;

	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
}

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)
{
	int ret;
	struct pt_regs regs;

	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &regs, 0, -1);
	if (ret)
		return ret;

	regs.sr = task_pt_regs(target)->sr;
#ifdef CONFIG_CPU_HAS_HILO
	regs.dcsr = task_pt_regs(target)->dcsr;
#endif
	task_thread_info(target)->tp_value = regs.tls;

	*task_pt_regs(target) = regs;

	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)
{
	struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;

#if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
	int i;
	struct user_fp tmp = *regs;

	for (i = 0; i < 16; i++) {
		tmp.vr[i*4] = regs->vr[i*2];
		tmp.vr[i*4 + 1] = regs->vr[i*2 + 1];
	}

	for (i = 0; i < 32; i++)
		tmp.vr[64 + i] = regs->vr[32 + i];

	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1);
#else
	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
#endif
}

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)
{
	int ret;
	struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;

#if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
	int i;
	struct user_fp tmp;

	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1);

	*regs = tmp;

	for (i = 0; i < 16; i++) {
		regs->vr[i*2] = tmp.vr[i*4];
		regs->vr[i*2 + 1] = tmp.vr[i*4 + 1];
	}

	for (i = 0; i < 32; i++)
		regs->vr[32 + i] = tmp.vr[64 + i];
#else
	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
#endif

	return ret;
}

static const struct user_regset csky_regsets[] = {
	[REGSET_GPR] = {
		.core_note_type = NT_PRSTATUS,
		.n = sizeof(struct pt_regs) / sizeof(u32),
		.size = sizeof(u32),
		.align = sizeof(u32),
		.get = &gpr_get,
		.set = &gpr_set,
	},
	[REGSET_FPR] = {
		.core_note_type = NT_PRFPREG,
		.n = sizeof(struct user_fp) / sizeof(u32),
		.size = sizeof(u32),
		.align = sizeof(u32),
		.get = &fpr_get,
		.set = &fpr_set,
	},
};

static const struct user_regset_view user_csky_view = {
	.name = "csky",
	.e_machine = ELF_ARCH,
	.regsets = csky_regsets,
	.n = ARRAY_SIZE(csky_regsets),
};

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

struct pt_regs_offset {
	const char *name;
	int offset;
};

#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
#define REG_OFFSET_END {.name = NULL, .offset = 0}

static const struct pt_regs_offset regoffset_table[] = {
	REG_OFFSET_NAME(tls),
	REG_OFFSET_NAME(lr),
	REG_OFFSET_NAME(pc),
	REG_OFFSET_NAME(sr),
	REG_OFFSET_NAME(usp),
	REG_OFFSET_NAME(orig_a0),
	REG_OFFSET_NAME(a0),
	REG_OFFSET_NAME(a1),
	REG_OFFSET_NAME(a2),
	REG_OFFSET_NAME(a3),
	REG_OFFSET_NAME(regs[0]),
	REG_OFFSET_NAME(regs[1]),
	REG_OFFSET_NAME(regs[2]),
	REG_OFFSET_NAME(regs[3]),
	REG_OFFSET_NAME(regs[4]),
	REG_OFFSET_NAME(regs[5]),
	REG_OFFSET_NAME(regs[6]),
	REG_OFFSET_NAME(regs[7]),
	REG_OFFSET_NAME(regs[8]),
	REG_OFFSET_NAME(regs[9]),
#if defined(__CSKYABIV2__)
	REG_OFFSET_NAME(exregs[0]),
	REG_OFFSET_NAME(exregs[1]),
	REG_OFFSET_NAME(exregs[2]),
	REG_OFFSET_NAME(exregs[3]),
	REG_OFFSET_NAME(exregs[4]),
	REG_OFFSET_NAME(exregs[5]),
	REG_OFFSET_NAME(exregs[6]),
	REG_OFFSET_NAME(exregs[7]),
	REG_OFFSET_NAME(exregs[8]),
	REG_OFFSET_NAME(exregs[9]),
	REG_OFFSET_NAME(exregs[10]),
	REG_OFFSET_NAME(exregs[11]),
	REG_OFFSET_NAME(exregs[12]),
	REG_OFFSET_NAME(exregs[13]),
	REG_OFFSET_NAME(exregs[