[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / tile / kernel / ptrace.c

/*
 * Copyright 2010 Tilera Corporation. All Rights Reserved.
 *
 *   This program is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU General Public License
 *   as published by the Free Software Foundation, version 2.
 *
 *   This program is distributed in the hope that it will be useful, but
 *   WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 *   NON INFRINGEMENT.  See the GNU General Public License for
 *   more details.
 *
 * Copied from i386: Ross Biro 1/23/92
 */

#include <linux/kernel.h>
#include <linux/ptrace.h>
#include <linux/kprobes.h>
#include <linux/compat.h>
#include <linux/uaccess.h>
#include <linux/regset.h>
#include <linux/elf.h>
#include <linux/tracehook.h>
#include <asm/traps.h>
#include <arch/chip.h>

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

void user_enable_single_step(struct task_struct *child)
{
	set_tsk_thread_flag(child, TIF_SINGLESTEP);
}

void user_disable_single_step(struct task_struct *child)
{
	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
}

/*
 * Called by kernel/ptrace.c when detaching..
 */
void ptrace_disable(struct task_struct *child)
{
	clear_tsk_thread_flag(child, TIF_SINGLESTEP);

	/*
	 * These two are currently unused, but will be set by arch_ptrace()
	 * and used in the syscall assembly when we do support them.
	 */
	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
}

/*
 * Get registers from task and ready the result for userspace.
 * Note that we localize the API issues to getregs() and putregs() at
 * some cost in performance, e.g. we need a full pt_regs copy for
 * PEEKUSR, and two copies for POKEUSR.  But in general we expect
 * GETREGS/PUTREGS to be the API of choice anyway.
 */
static char *getregs(struct task_struct *child, struct pt_regs *uregs)
{
	*uregs = *task_pt_regs(child);

	/* Set up flags ABI bits. */
	uregs->flags = 0;
#ifdef CONFIG_COMPAT
	if (task_thread_info(child)->status & TS_COMPAT)
		uregs->flags |= PT_FLAGS_COMPAT;
#endif

	return (char *)uregs;
}

/* Put registers back to task. */
static void putregs(struct task_struct *child, struct pt_regs *uregs)
{
	struct pt_regs *regs = task_pt_regs(child);

	/* Don't allow overwriting the kernel-internal flags word. */
	uregs->flags = regs->flags;

	/* Only allow setting the ICS bit in the ex1 word. */
	uregs->ex1 = PL_ICS_EX1(USER_PL, EX1_ICS(uregs->ex1));

	*regs = *uregs;
}

enum tile_regset {
	REGSET_GPR,
};

static int tile_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;

	getregs(target, &regs);

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

static int tile_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 = *task_pt_regs(target);

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

	putregs(target, &regs);

	return 0;
}

static const struct user_regset tile_user_regset[] = {
	[REGSET_GPR] = {
		.core_note_type = NT_PRSTATUS,
		.n = ELF_NGREG,
		.size = sizeof(elf_greg_t),
		.align = sizeof(elf_greg_t),
		.get = tile_gpr_get,
		.set = tile_gpr_set,
	},
};

static const struct user_regset_view tile_user_regset_view = {
	.name = CHIP_ARCH_NAME,
	.e_machine = ELF_ARCH,
	.ei_osabi = ELF_OSABI,
	.regsets = tile_user_regset,
	.n = ARRAY_SIZE(tile_user_regset),
};

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

long arch_ptrace(struct task_struct *child, long request,
		 unsigned long addr, unsigned long data)
{
	unsigned long __user *datap = (long __user __force *)data;
	unsigned long tmp;
	long ret = -EIO;
	char *childreg;
	struct pt_regs copyregs;

	switch (request) {

	case PTRACE_PEEKUSR:  /* Read register from pt_regs. */
		if (addr >= PTREGS_SIZE)
			break;
		childreg = getregs(child, &copyregs) + addr;
#ifdef CONFIG_COMPAT
		if (is_compat_task()) {
			if (addr & (sizeof(compat_long_t)-1))
				break;
			ret = put_user(*(compat_long_t *)childreg,
				       (compat_long_t __user *)datap);
		} else
#endif
		{
			if (addr & (sizeof(long)-1))
				break;
			ret = put_user(*(long *)childreg, datap);
		}
		break;

	case PTRACE_POKEUSR:  /* Write register in pt_regs. */
		if (addr >= PTREGS_SIZE)
			break;
		childreg = getregs(child, &copyregs) + addr;
#ifdef CONFIG_COMPAT
		if (is_compat_task()) {
			if (addr & (sizeof(compat_long_t)-1))
				break;
			*(compat_long_t *)childreg = data;
		} else
#endif
		{
			if (addr & (sizeof(long)-1))
				break;
			*(long *)childreg = data;
		}
		putregs(child, &copyregs);
		ret = 0;
		break;

	case PTRACE_GETREGS:  /* Get all registers from the child. */
		ret = copy_regset_to_user(child, &tile_user_regset_view,
					  REGSET_GPR, 0,
					  sizeof(struct pt_regs), datap);
		break;

	case PTRACE_SETREGS:  /* Set all registers in the child. */
		ret = copy_regset_from_user(child, &tile_user_regset_view,
					    REGSET_GPR, 0,
					    sizeof(struct pt_regs), datap);
		break;

	case PTRACE_GETFPREGS:  /* Get the child FPU state. */
	case PTRACE_SETFPREGS:  /* Set the child FPU state. */
		break;

	case PTRACE_SETOPTIONS:
		/* Support TILE-specific ptrace options. */
		BUILD_BUG_ON(PTRACE_O_MASK_TILE & PTRACE_O_MASK);
		tmp = data & PTRACE_O_MASK_TILE;
		data &= ~PTRACE_O_MASK_TILE;
		ret = ptrace_request(child, request, addr, data);
		if (ret == 0) {
			unsigned int flags = child->ptrace;
			flags &= ~(PTRACE_O_MASK_TILE << PT_OPT_FLAG_SHIFT);
			flags |= (tmp << PT_OPT_FLAG_SHIFT);
			child->ptrace = flags;
		}
		break;

	default:
#ifdef CONFIG_COMPAT
		if (task_thread_info(current)->status & TS_COMPAT) {
			ret = compat_ptrace_request(child, request,
						    addr, data);
			break;
		}
#endif
		ret = ptrace_request(child, request, addr, data);
		break;
	}

	return ret;
}

#ifdef CONFIG_COMPAT
/* Not used; we handle compat issues in arch_ptrace() directly. */
long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
			       compat_ulong_t addr, compat_ulong_t data)
{
	BUG();
}
#endif

int do_syscall_trace_enter(struct pt_regs *regs)
{
	if (test_thread_flag(TIF_SYSCALL_TRACE)) {
		if (tracehook_report_syscall_entry(regs))
			regs->regs[TREG_SYSCALL_NR] = -1;
	}

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

	return regs->regs[TREG_SYSCALL_NR];
}

void do_syscall_trace_exit(struct pt_regs *regs)
{
	if (test_thread_flag(TIF_SYSCALL_TRACE))
		tracehook_report_syscall_exit(regs, 0);

	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
		trace_sys_exit(regs, regs->regs[0]);
}

void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
{
	struct siginfo info;

	memset(&info, 0, sizeof(info));
	info.si_signo = SIGTRAP;
	info.si_code  = TRAP_BRKPT;
	info.si_addr  = (void __user *) regs->pc;

	/* Send us the fakey SIGTRAP */
	force_sig_info(SIGTRAP, &info, tsk);
}

/* Handle synthetic interrupt delivered only by the simulator. */
void __kprobes do_breakpoint(struct pt_regs* regs, int fault_num)
{
	send_sigtrap(current, regs, fault_num);
}
Commit	Line	Data
867e359b CM	1	/*
	2	* Copyright 2010 Tilera Corporation. All Rights Reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License
	6	* as published by the Free Software Foundation, version 2.
	7	*
	8	* This program is distributed in the hope that it will be useful, but
	9	* WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
	11	* NON INFRINGEMENT. See the GNU General Public License for
	12	* more details.
	13	*
	14	* Copied from i386: Ross Biro 1/23/92
	15	*/
	16
	17	#include <linux/kernel.h>
	18	#include <linux/ptrace.h>
	19	#include <linux/kprobes.h>
	20	#include <linux/compat.h>
	21	#include <linux/uaccess.h>
7be68284 SM	22	#include <linux/regset.h>
7be68284 SM	23	#include <linux/elf.h>
ef182724	24	#include <linux/tracehook.h>
0707ad30	25	#include <asm/traps.h>
7be68284	26	#include <arch/chip.h>
867e359b	27
ef567f25 SM	28	#define CREATE_TRACE_POINTS
	29	#include <trace/events/syscalls.h>
	30
867e359b CM	31	void user_enable_single_step(struct task_struct *child)
	32	{
	33	set_tsk_thread_flag(child, TIF_SINGLESTEP);
	34	}
	35
	36	void user_disable_single_step(struct task_struct *child)
	37	{
	38	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
	39	}
	40
867e359b CM	41	/*
	42	* Called by kernel/ptrace.c when detaching..
	43	*/
	44	void ptrace_disable(struct task_struct *child)
	45	{
	46	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
	47
	48	/*
	49	* These two are currently unused, but will be set by arch_ptrace()
	50	* and used in the syscall assembly when we do support them.
	51	*/
	52	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
	53	}
	54
cb67e161 CM	55	/*
	56	* Get registers from task and ready the result for userspace.
	57	* Note that we localize the API issues to getregs() and putregs() at
	58	* some cost in performance, e.g. we need a full pt_regs copy for
	59	* PEEKUSR, and two copies for POKEUSR. But in general we expect
	60	* GETREGS/PUTREGS to be the API of choice anyway.
	61	*/
	62	static char getregs(struct task_struct child, struct pt_regs *uregs)
	63	{
	64	uregs = task_pt_regs(child);
	65
	66	/* Set up flags ABI bits. */
	67	uregs->flags = 0;
	68	#ifdef CONFIG_COMPAT
	69	if (task_thread_info(child)->status & TS_COMPAT)
	70	uregs->flags \|= PT_FLAGS_COMPAT;
	71	#endif
	72
	73	return (char *)uregs;
	74	}
	75
	76	/* Put registers back to task. */
	77	static void putregs(struct task_struct child, struct pt_regs uregs)
	78	{
	79	struct pt_regs *regs = task_pt_regs(child);
	80
	81	/* Don't allow overwriting the kernel-internal flags word. */
	82	uregs->flags = regs->flags;
	83
	84	/* Only allow setting the ICS bit in the ex1 word. */
	85	uregs->ex1 = PL_ICS_EX1(USER_PL, EX1_ICS(uregs->ex1));
	86
	87	regs = uregs;
	88	}
	89
7be68284 SM	90	enum tile_regset {
	91	REGSET_GPR,
	92	};
	93
	94	static int tile_gpr_get(struct task_struct *target,
	95	const struct user_regset *regset,
	96	unsigned int pos, unsigned int count,
	97	void kbuf, void __user ubuf)
	98	{
	99	struct pt_regs regs;
	100
	101	getregs(target, &regs);
	102
	103	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &regs, 0,
	104	sizeof(regs));
	105	}
	106
	107	static int tile_gpr_set(struct task_struct *target,
	108	const struct user_regset *regset,
	109	unsigned int pos, unsigned int count,
	110	const void kbuf, const void __user ubuf)
	111	{
	112	int ret;
3cc334c2	113	struct pt_regs regs = *task_pt_regs(target);
7be68284 SM	114
	115	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &regs, 0,
	116	sizeof(regs));
	117	if (ret)
	118	return ret;
	119
	120	putregs(target, &regs);
	121
	122	return 0;
	123	}
	124
	125	static const struct user_regset tile_user_regset[] = {
	126	[REGSET_GPR] = {
	127	.core_note_type = NT_PRSTATUS,
	128	.n = ELF_NGREG,
	129	.size = sizeof(elf_greg_t),
	130	.align = sizeof(elf_greg_t),
	131	.get = tile_gpr_get,
	132	.set = tile_gpr_set,
	133	},
	134	};
	135
	136	static const struct user_regset_view tile_user_regset_view = {
	137	.name = CHIP_ARCH_NAME,
	138	.e_machine = ELF_ARCH,
	139	.ei_osabi = ELF_OSABI,
	140	.regsets = tile_user_regset,
	141	.n = ARRAY_SIZE(tile_user_regset),
	142	};
	143
	144	const struct user_regset_view task_user_regset_view(struct task_struct task)
	145	{
	146	return &tile_user_regset_view;
	147	}
	148
9b05a69e NK	149	long arch_ptrace(struct task_struct *child, long request,
9b05a69e NK	150	unsigned long addr, unsigned long data)
867e359b	151	{
ce7f2a39	152	unsigned long __user datap = (long __user __force )data;
867e359b	153	unsigned long tmp;
867e359b	154	long ret = -EIO;
ce7f2a39	155	char *childreg;
1deb9c5d	156	struct pt_regs copyregs;
867e359b CM	157
	158	switch (request) {
	159
	160	case PTRACE_PEEKUSR: /* Read register from pt_regs. */
8c0acac3	161	if (addr >= PTREGS_SIZE)
867e359b	162	break;
cb67e161	163	childreg = getregs(child, &copyregs) + addr;
ce7f2a39 CM	164	#ifdef CONFIG_COMPAT
	165	if (is_compat_task()) {
	166	if (addr & (sizeof(compat_long_t)-1))
	167	break;
	168	ret = put_user((compat_long_t )childreg,
	169	(compat_long_t __user *)datap);
	170	} else
	171	#endif
	172	{
	173	if (addr & (sizeof(long)-1))
	174	break;
	175	ret = put_user((long )childreg, datap);
	176	}
867e359b CM	177	break;
	178
	179	case PTRACE_POKEUSR: /* Write register in pt_regs. */
8c0acac3	180	if (addr >= PTREGS_SIZE)
867e359b	181	break;
cb67e161	182	childreg = getregs(child, &copyregs) + addr;
ce7f2a39 CM	183	#ifdef CONFIG_COMPAT
	184	if (is_compat_task()) {
	185	if (addr & (sizeof(compat_long_t)-1))
	186	break;
	187	(compat_long_t )childreg = data;
	188	} else
	189	#endif
	190	{
	191	if (addr & (sizeof(long)-1))
	192	break;
	193	(long )childreg = data;
	194	}
cb67e161	195	putregs(child, &copyregs);
bcd97c3f	196	ret = 0;
867e359b CM	197	break;
	198
	199	case PTRACE_GETREGS: /* Get all registers from the child. */
9af62547 SM	200	ret = copy_regset_to_user(child, &tile_user_regset_view,
	201	REGSET_GPR, 0,
	202	sizeof(struct pt_regs), datap);
867e359b CM	203	break;
	204
	205	case PTRACE_SETREGS: /* Set all registers in the child. */
9af62547 SM	206	ret = copy_regset_from_user(child, &tile_user_regset_view,
	207	REGSET_GPR, 0,
	208	sizeof(struct pt_regs), datap);
867e359b CM	209	break;
	210
	211	case PTRACE_GETFPREGS: /* Get the child FPU state. */
	212	case PTRACE_SETFPREGS: /* Set the child FPU state. */
	213	break;
	214
	215	case PTRACE_SETOPTIONS:
	216	/* Support TILE-specific ptrace options. */
395e095e	217	BUILD_BUG_ON(PTRACE_O_MASK_TILE & PTRACE_O_MASK);
867e359b CM	218	tmp = data & PTRACE_O_MASK_TILE;
	219	data &= ~PTRACE_O_MASK_TILE;
	220	ret = ptrace_request(child, request, addr, data);
395e095e CM	221	if (ret == 0) {
	222	unsigned int flags = child->ptrace;
	223	flags &= ~(PTRACE_O_MASK_TILE << PT_OPT_FLAG_SHIFT);
	224	flags \|= (tmp << PT_OPT_FLAG_SHIFT);
	225	child->ptrace = flags;
	226	}
867e359b CM	227	break;
	228
	229	default:
	230	#ifdef CONFIG_COMPAT
	231	if (task_thread_info(current)->status & TS_COMPAT) {
	232	ret = compat_ptrace_request(child, request,
	233	addr, data);
	234	break;
	235	}
	236	#endif
	237	ret = ptrace_request(child, request, addr, data);
	238	break;
	239	}
	240
	241	return ret;
	242	}
	243
	244	#ifdef CONFIG_COMPAT
	245	/* Not used; we handle compat issues in arch_ptrace() directly. */
	246	long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
	247	compat_ulong_t addr, compat_ulong_t data)
	248	{
	249	BUG();
	250	}
	251	#endif
	252
ef182724	253	int do_syscall_trace_enter(struct pt_regs *regs)
867e359b	254	{
ef567f25 SM	255	if (test_thread_flag(TIF_SYSCALL_TRACE)) {
	256	if (tracehook_report_syscall_entry(regs))
	257	regs->regs[TREG_SYSCALL_NR] = -1;
ef182724	258	}
867e359b	259
ef567f25 SM	260	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
	261	trace_sys_enter(regs, regs->regs[TREG_SYSCALL_NR]);
	262
ef182724 SM	263	return regs->regs[TREG_SYSCALL_NR];
ef182724 SM	264	}
867e359b	265
ef182724 SM	266	void do_syscall_trace_exit(struct pt_regs *regs)
ef182724 SM	267	{
ef567f25 SM	268	if (test_thread_flag(TIF_SYSCALL_TRACE))
	269	tracehook_report_syscall_exit(regs, 0);
	270
	271	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
9fc1894c	272	trace_sys_exit(regs, regs->regs[0]);
867e359b CM	273	}
	274
	275	void send_sigtrap(struct task_struct tsk, struct pt_regs regs, int error_code)
	276	{
	277	struct siginfo info;
	278
	279	memset(&info, 0, sizeof(info));
	280	info.si_signo = SIGTRAP;
	281	info.si_code = TRAP_BRKPT;
	282	info.si_addr = (void __user *) regs->pc;
	283
	284	/* Send us the fakey SIGTRAP */
	285	force_sig_info(SIGTRAP, &info, tsk);
	286	}
	287
	288	/* Handle synthetic interrupt delivered only by the simulator. */
	289	void __kprobes do_breakpoint(struct pt_regs* regs, int fault_num)
	290	{
	291	send_sigtrap(current, regs, fault_num);
	292	}