[deliverable/linux.git] / arch / x86 / um / ptrace_32.c

/*
 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 * Licensed under the GPL
 */

#include <linux/mm.h>
#include <linux/sched.h>
#include <asm/uaccess.h>
#include <skas.h>

extern int arch_switch_tls(struct task_struct *to);

void arch_switch_to(struct task_struct *to)
{
	int err = arch_switch_tls(to);
	if (!err)
		return;

	if (err != -EINVAL)
		printk(KERN_WARNING "arch_switch_tls failed, errno %d, "
		       "not EINVAL\n", -err);
	else
		printk(KERN_WARNING "arch_switch_tls failed, errno = EINVAL\n");
}

int is_syscall(unsigned long addr)
{
	unsigned short instr;
	int n;

	n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
	if (n) {
		/* access_process_vm() grants access to vsyscall and stub,
		 * while copy_from_user doesn't. Maybe access_process_vm is
		 * slow, but that doesn't matter, since it will be called only
		 * in case of singlestepping, if copy_from_user failed.
		 */
		n = access_process_vm(current, addr, &instr, sizeof(instr), 0);
		if (n != sizeof(instr)) {
			printk(KERN_ERR "is_syscall : failed to read "
			       "instruction from 0x%lx\n", addr);
			return 1;
		}
	}
	/* int 0x80 or sysenter */
	return (instr == 0x80cd) || (instr == 0x340f);
}

/* determines which flags the user has access to. */
/* 1 = access 0 = no access */
#define FLAG_MASK 0x00044dd5

static const int reg_offsets[] = {
	[EBX] = HOST_BX,
	[ECX] = HOST_CX,
	[EDX] = HOST_DX,
	[ESI] = HOST_SI,
	[EDI] = HOST_DI,
	[EBP] = HOST_BP,
	[EAX] = HOST_AX,
	[DS] = HOST_DS,
	[ES] = HOST_ES,
	[FS] = HOST_FS,
	[GS] = HOST_GS,
	[EIP] = HOST_IP,
	[CS] = HOST_CS,
	[EFL] = HOST_EFLAGS,
	[UESP] = HOST_SP,
	[SS] = HOST_SS,
};

int putreg(struct task_struct *child, int regno, unsigned long value)
{
	regno >>= 2;
	switch (regno) {
	case EBX:
	case ECX:
	case EDX:
	case ESI:
	case EDI:
	case EBP:
	case EAX:
	case EIP:
	case UESP:
		break;
	case FS:
		if (value && (value & 3) != 3)
			return -EIO;
		break;
	case GS:
		if (value && (value & 3) != 3)
			return -EIO;
		break;
	case DS:
	case ES:
		if (value && (value & 3) != 3)
			return -EIO;
		value &= 0xffff;
		break;
	case SS:
	case CS:
		if ((value & 3) != 3)
			return -EIO;
		value &= 0xffff;
		break;
	case EFL:
		value &= FLAG_MASK;
		child->thread.regs.regs.gp[HOST_EFLAGS] |= value;
		return 0;
	case ORIG_EAX:
		child->thread.regs.regs.syscall = value;
		return 0;
	default :
		panic("Bad register in putreg() : %d\n", regno);
	}
	child->thread.regs.regs.gp[reg_offsets[regno]] = value;
	return 0;
}

int poke_user(struct task_struct *child, long addr, long data)
{
	if ((addr & 3) || addr < 0)
		return -EIO;

	if (addr < MAX_REG_OFFSET)
		return putreg(child, addr, data);
	else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
		 (addr <= offsetof(struct user, u_debugreg[7]))) {
		addr -= offsetof(struct user, u_debugreg[0]);
		addr = addr >> 2;
		if ((addr == 4) || (addr == 5))
			return -EIO;
		child->thread.arch.debugregs[addr] = data;
		return 0;
	}
	return -EIO;
}

unsigned long getreg(struct task_struct *child, int regno)
{
	unsigned long mask = ~0UL;

	regno >>= 2;
	switch (regno) {
	case ORIG_EAX:
		return child->thread.regs.regs.syscall;
	case FS:
	case GS:
	case DS:
	case ES:
	case SS:
	case CS:
		mask = 0xffff;
		break;
	case EIP:
	case UESP:
	case EAX:
	case EBX:
	case ECX:
	case EDX:
	case ESI:
	case EDI:
	case EBP:
	case EFL:
		break;
	default:
		panic("Bad register in getreg() : %d\n", regno);
	}
	return mask & child->thread.regs.regs.gp[reg_offsets[regno]];
}

/* read the word at location addr in the USER area. */
int peek_user(struct task_struct *child, long addr, long data)
{
	unsigned long tmp;

	if ((addr & 3) || addr < 0)
		return -EIO;

	tmp = 0;  /* Default return condition */
	if (addr < MAX_REG_OFFSET) {
		tmp = getreg(child, addr);
	}
	else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
		 (addr <= offsetof(struct user, u_debugreg[7]))) {
		addr -= offsetof(struct user, u_debugreg[0]);
		addr = addr >> 2;
		tmp = child->thread.arch.debugregs[addr];
	}
	return put_user(tmp, (unsigned long __user *) data);
}

static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
{
	int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
	struct user_i387_struct fpregs;

	err = save_fp_registers(userspace_pid[cpu], (unsigned long *) &fpregs);
	if (err)
		return err;

	n = copy_to_user(buf, &fpregs, sizeof(fpregs));
	if(n > 0)
		return -EFAULT;

	return n;
}

static int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
{
	int n, cpu = ((struct thread_info *) child->stack)->cpu;
	struct user_i387_struct fpregs;

	n = copy_from_user(&fpregs, buf, sizeof(fpregs));
	if (n > 0)
		return -EFAULT;

	return restore_fp_registers(userspace_pid[cpu],
				    (unsigned long *) &fpregs);
}

static int get_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
{
	int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
	struct user_fxsr_struct fpregs;

	err = save_fpx_registers(userspace_pid[cpu], (unsigned long *) &fpregs);
	if (err)
		return err;

	n = copy_to_user(buf, &fpregs, sizeof(fpregs));
	if(n > 0)
		return -EFAULT;

	return n;
}

static int set_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
{
	int n, cpu = ((struct thread_info *) child->stack)->cpu;
	struct user_fxsr_struct fpregs;

	n = copy_from_user(&fpregs, buf, sizeof(fpregs));
	if (n > 0)
		return -EFAULT;

	return restore_fpx_registers(userspace_pid[cpu],
				     (unsigned long *) &fpregs);
}

long subarch_ptrace(struct task_struct *child, long request,
		    unsigned long addr, unsigned long data)
{
	int ret = -EIO;
	void __user *datap = (void __user *) data;
	switch (request) {
	case PTRACE_GETFPREGS: /* Get the child FPU state. */
		ret = get_fpregs(datap, child);
		break;
	case PTRACE_SETFPREGS: /* Set the child FPU state. */
		ret = set_fpregs(datap, child);
		break;
	case PTRACE_GETFPXREGS: /* Get the child FPU state. */
		ret = get_fpxregs(datap, child);
		break;
	case PTRACE_SETFPXREGS: /* Set the child FPU state. */
		ret = set_fpxregs(datap, child);
		break;
	default:
		ret = -EIO;
	}
	return ret;
}
Commit	Line	Data
ba180fd4 JD	1	/*
ba180fd4 JD	2	* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
1da177e4 LT	3	* Licensed under the GPL
	4	*/
	5
37185b33 AV	6	#include <linux/mm.h>
	7	#include <linux/sched.h>
	8	#include <asm/uaccess.h>
	9	#include <skas.h>
1da177e4	10
291248fd	11	extern int arch_switch_tls(struct task_struct *to);
77bf4400	12
291248fd	13	void arch_switch_to(struct task_struct *to)
1da177e4	14	{
291248fd	15	int err = arch_switch_tls(to);
54d8d3b5 PBG	16	if (!err)
	17	return;
	18
	19	if (err != -EINVAL)
ba180fd4 JD	20	printk(KERN_WARNING "arch_switch_tls failed, errno %d, "
ba180fd4 JD	21	"not EINVAL\n", -err);
54d8d3b5	22	else
77bf4400	23	printk(KERN_WARNING "arch_switch_tls failed, errno = EINVAL\n");
1da177e4 LT	24	}
	25
	26	int is_syscall(unsigned long addr)
	27	{
	28	unsigned short instr;
	29	int n;
	30
	31	n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
ba180fd4	32	if (n) {
81efcd33 BS	33	/* access_process_vm() grants access to vsyscall and stub,
	34	* while copy_from_user doesn't. Maybe access_process_vm is
	35	* slow, but that doesn't matter, since it will be called only
	36	* in case of singlestepping, if copy_from_user failed.
	37	*/
	38	n = access_process_vm(current, addr, &instr, sizeof(instr), 0);
ba180fd4 JD	39	if (n != sizeof(instr)) {
	40	printk(KERN_ERR "is_syscall : failed to read "
	41	"instruction from 0x%lx\n", addr);
	42	return 1;
81efcd33	43	}
1da177e4 LT	44	}
1da177e4 LT	45	/* int 0x80 or sysenter */
ba180fd4	46	return (instr == 0x80cd) \|\| (instr == 0x340f);
1da177e4 LT	47	}
	48
	49	/* determines which flags the user has access to. */
	50	/* 1 = access 0 = no access */
	51	#define FLAG_MASK 0x00044dd5
	52
412f90ed	53	static const int reg_offsets[] = {
3579a389 AV	54	[EBX] = HOST_BX,
	55	[ECX] = HOST_CX,
	56	[EDX] = HOST_DX,
	57	[ESI] = HOST_SI,
	58	[EDI] = HOST_DI,
	59	[EBP] = HOST_BP,
	60	[EAX] = HOST_AX,
412f90ed AV	61	[DS] = HOST_DS,
	62	[ES] = HOST_ES,
	63	[FS] = HOST_FS,
	64	[GS] = HOST_GS,
	65	[EIP] = HOST_IP,
	66	[CS] = HOST_CS,
	67	[EFL] = HOST_EFLAGS,
	68	[UESP] = HOST_SP,
	69	[SS] = HOST_SS,
	70	};
	71
1da177e4 LT	72	int putreg(struct task_struct *child, int regno, unsigned long value)
	73	{
	74	regno >>= 2;
	75	switch (regno) {
412f90ed AV	76	case EBX:
	77	case ECX:
	78	case EDX:
	79	case ESI:
	80	case EDI:
	81	case EBP:
	82	case EAX:
	83	case EIP:
	84	case UESP:
	85	break;
1da177e4 LT	86	case FS:
	87	if (value && (value & 3) != 3)
	88	return -EIO;
412f90ed	89	break;
1da177e4 LT	90	case GS:
	91	if (value && (value & 3) != 3)
	92	return -EIO;
412f90ed	93	break;
1da177e4 LT	94	case DS:
	95	case ES:
	96	if (value && (value & 3) != 3)
	97	return -EIO;
	98	value &= 0xffff;
	99	break;
	100	case SS:
	101	case CS:
	102	if ((value & 3) != 3)
	103	return -EIO;
	104	value &= 0xffff;
	105	break;
	106	case EFL:
	107	value &= FLAG_MASK;
412f90ed AV	108	child->thread.regs.regs.gp[HOST_EFLAGS] \|= value;
	109	return 0;
	110	case ORIG_EAX:
	111	child->thread.regs.regs.syscall = value;
	112	return 0;
	113	default :
	114	panic("Bad register in putreg() : %d\n", regno);
1da177e4	115	}
412f90ed	116	child->thread.regs.regs.gp[reg_offsets[regno]] = value;
1da177e4 LT	117	return 0;
	118	}
	119
82c1c11b BS	120	int poke_user(struct task_struct *child, long addr, long data)
82c1c11b BS	121	{
ba180fd4 JD	122	if ((addr & 3) \|\| addr < 0)
	123	return -EIO;
	124
	125	if (addr < MAX_REG_OFFSET)
	126	return putreg(child, addr, data);
	127	else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
	128	(addr <= offsetof(struct user, u_debugreg[7]))) {
	129	addr -= offsetof(struct user, u_debugreg[0]);
	130	addr = addr >> 2;
	131	if ((addr == 4) \|\| (addr == 5))
	132	return -EIO;
	133	child->thread.arch.debugregs[addr] = data;
	134	return 0;
	135	}
	136	return -EIO;
82c1c11b BS	137	}
82c1c11b BS	138
1da177e4 LT	139	unsigned long getreg(struct task_struct *child, int regno)
1da177e4 LT	140	{
412f90ed	141	unsigned long mask = ~0UL;
1da177e4 LT	142
	143	regno >>= 2;
	144	switch (regno) {
412f90ed AV	145	case ORIG_EAX:
412f90ed AV	146	return child->thread.regs.regs.syscall;
1da177e4 LT	147	case FS:
	148	case GS:
	149	case DS:
	150	case ES:
	151	case SS:
	152	case CS:
412f90ed AV	153	mask = 0xffff;
	154	break;
	155	case EIP:
	156	case UESP:
	157	case EAX:
	158	case EBX:
	159	case ECX:
	160	case EDX:
	161	case ESI:
	162	case EDI:
	163	case EBP:
	164	case EFL:
	165	break;
1da177e4	166	default:
412f90ed	167	panic("Bad register in getreg() : %d\n", regno);
1da177e4	168	}
412f90ed	169	return mask & child->thread.regs.regs.gp[reg_offsets[regno]];
1da177e4 LT	170	}
1da177e4 LT	171
ba180fd4	172	/* read the word at location addr in the USER area. */
82c1c11b BS	173	int peek_user(struct task_struct *child, long addr, long data)
82c1c11b BS	174	{
4d338e1a	175	unsigned long tmp;
82c1c11b	176
4d338e1a AV	177	if ((addr & 3) \|\| addr < 0)
4d338e1a AV	178	return -EIO;
82c1c11b	179
4d338e1a	180	tmp = 0; /* Default return condition */
ba180fd4	181	if (addr < MAX_REG_OFFSET) {
4d338e1a AV	182	tmp = getreg(child, addr);
4d338e1a AV	183	}
ba180fd4 JD	184	else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
ba180fd4 JD	185	(addr <= offsetof(struct user, u_debugreg[7]))) {
4d338e1a AV	186	addr -= offsetof(struct user, u_debugreg[0]);
	187	addr = addr >> 2;
	188	tmp = child->thread.arch.debugregs[addr];
	189	}
	190	return put_user(tmp, (unsigned long __user *) data);
82c1c11b BS	191	}
82c1c11b BS	192
f2833aef	193	static int get_fpregs(struct user_i387_struct __user buf, struct task_struct child)
1da177e4	194	{
e8012b58	195	int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
47906dd9	196	struct user_i387_struct fpregs;
1da177e4	197
47906dd9	198	err = save_fp_registers(userspace_pid[cpu], (unsigned long *) &fpregs);
e8012b58 JD	199	if (err)
	200	return err;
	201
47906dd9	202	n = copy_to_user(buf, &fpregs, sizeof(fpregs));
e8012b58 JD	203	if(n > 0)
	204	return -EFAULT;
	205
	206	return n;
1da177e4 LT	207	}
1da177e4 LT	208
f2833aef	209	static int set_fpregs(struct user_i387_struct __user buf, struct task_struct child)
1da177e4	210	{
e8012b58	211	int n, cpu = ((struct thread_info *) child->stack)->cpu;
47906dd9	212	struct user_i387_struct fpregs;
1da177e4	213
47906dd9	214	n = copy_from_user(&fpregs, buf, sizeof(fpregs));
e8012b58	215	if (n > 0)
ba180fd4	216	return -EFAULT;
e8012b58	217
47906dd9 JD	218	return restore_fp_registers(userspace_pid[cpu],
47906dd9 JD	219	(unsigned long *) &fpregs);
1da177e4 LT	220	}
1da177e4 LT	221
f2833aef	222	static int get_fpxregs(struct user_fxsr_struct __user buf, struct task_struct child)
1da177e4	223	{
e8012b58	224	int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
47906dd9	225	struct user_fxsr_struct fpregs;
1da177e4	226
47906dd9	227	err = save_fpx_registers(userspace_pid[cpu], (unsigned long *) &fpregs);
ba180fd4	228	if (err)
e8012b58 JD	229	return err;
e8012b58 JD	230
47906dd9	231	n = copy_to_user(buf, &fpregs, sizeof(fpregs));
e8012b58	232	if(n > 0)
ba180fd4	233	return -EFAULT;
1da177e4	234
e8012b58	235	return n;
1da177e4 LT	236	}
1da177e4 LT	237
f2833aef	238	static int set_fpxregs(struct user_fxsr_struct __user buf, struct task_struct child)
1da177e4	239	{
e8012b58	240	int n, cpu = ((struct thread_info *) child->stack)->cpu;
47906dd9	241	struct user_fxsr_struct fpregs;
e8012b58	242
47906dd9	243	n = copy_from_user(&fpregs, buf, sizeof(fpregs));
e8012b58 JD	244	if (n > 0)
	245	return -EFAULT;
	246
47906dd9 JD	247	return restore_fpx_registers(userspace_pid[cpu],
47906dd9 JD	248	(unsigned long *) &fpregs);
1da177e4 LT	249	}
1da177e4 LT	250
9b05a69e NK	251	long subarch_ptrace(struct task_struct *child, long request,
9b05a69e NK	252	unsigned long addr, unsigned long data)
e8012b58	253	{
01599cdc AV	254	int ret = -EIO;
01599cdc AV	255	void __user datap = (void __user ) data;
01599cdc	256	switch (request) {
f2833aef AV	257	case PTRACE_GETFPREGS: /* Get the child FPU state. */
	258	ret = get_fpregs(datap, child);
	259	break;
	260	case PTRACE_SETFPREGS: /* Set the child FPU state. */
	261	ret = set_fpregs(datap, child);
	262	break;
01599cdc AV	263	case PTRACE_GETFPXREGS: /* Get the child FPU state. */
	264	ret = get_fpxregs(datap, child);
	265	break;
	266	case PTRACE_SETFPXREGS: /* Set the child FPU state. */
	267	ret = set_fpxregs(datap, child);
	268	break;
f2833aef AV	269	default:
f2833aef AV	270	ret = -EIO;
01599cdc	271	}
01599cdc	272	return ret;
e8012b58	273	}