[deliverable/linux.git] / arch / um / sys-i386 / ptrace.c

/* 
 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
 * Licensed under the GPL
 */

#include <linux/compiler.h>
#include "linux/sched.h"
#include "linux/mm.h"
#include "asm/elf.h"
#include "asm/ptrace.h"
#include "asm/uaccess.h"
#include "asm/unistd.h"
#include "sysdep/ptrace.h"
#include "sysdep/sigcontext.h"
#include "sysdep/sc.h"

void arch_switch_to_skas(struct task_struct *from, struct task_struct *to)
{
	int err = arch_switch_tls_skas(from, to);
	if (!err)
		return;

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

int putreg(struct task_struct *child, int regno, unsigned long value)
{
	regno >>= 2;
	switch (regno) {
	case FS:
		if (value && (value & 3) != 3)
			return -EIO;
		PT_REGS_FS(&child->thread.regs) = value;
		return 0;
	case GS:
		if (value && (value & 3) != 3)
			return -EIO;
		PT_REGS_GS(&child->thread.regs) = value;
		return 0;
	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;
		value |= PT_REGS_EFLAGS(&child->thread.regs);
		break;
	}
	PT_REGS_SET(&child->thread.regs, 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 retval = ~0UL;

	regno >>= 2;
	switch (regno) {
	case FS:
	case GS:
	case DS:
	case ES:
	case SS:
	case CS:
		retval = 0xffff;
		/* fall through */
	default:
		retval &= PT_REG(&child->thread.regs, regno);
	}
	return retval;
}

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

struct i387_fxsave_struct {
	unsigned short	cwd;
	unsigned short	swd;
	unsigned short	twd;
	unsigned short	fop;
	long	fip;
	long	fcs;
	long	foo;
	long	fos;
	long	mxcsr;
	long	reserved;
	long	st_space[32];	/* 8*16 bytes for each FP-reg = 128 bytes */
	long	xmm_space[32];	/* 8*16 bytes for each XMM-reg = 128 bytes */
	long	padding[56];
};

/*
 * FPU tag word conversions.
 */

static inline unsigned short twd_i387_to_fxsr( unsigned short twd )
{
	unsigned int tmp; /* to avoid 16 bit prefixes in the code */
 
	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
        tmp = ~twd;
        tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
        /* and move the valid bits to the lower byte. */
        tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
        tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
        tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
        return tmp;
}

static inline unsigned long twd_fxsr_to_i387( struct i387_fxsave_struct *fxsave )
{
	struct _fpxreg *st = NULL;
	unsigned long twd = (unsigned long) fxsave->twd;
	unsigned long tag;
	unsigned long ret = 0xffff0000;
	int i;

#define FPREG_ADDR(f, n)	((char *)&(f)->st_space + (n) * 16);

	for ( i = 0 ; i < 8 ; i++ ) {
		if ( twd & 0x1 ) {
			st = (struct _fpxreg *) FPREG_ADDR( fxsave, i );

			switch ( st->exponent & 0x7fff ) {
			case 0x7fff:
				tag = 2;		/* Special */
				break;
			case 0x0000:
				if ( !st->significand[0] &&
				     !st->significand[1] &&
				     !st->significand[2] &&
				     !st->significand[3] ) {
					tag = 1;	/* Zero */
				} else {
					tag = 2;	/* Special */
				}
				break;
			default:
				if ( st->significand[3] & 0x8000 ) {
					tag = 0;	/* Valid */
				} else {
					tag = 2;	/* Special */
				}
				break;
			}
		} else {
			tag = 3;			/* Empty */
		}
		ret |= (tag << (2 * i));
		twd = twd >> 1;
	}
	return ret;
}

static inline int convert_fxsr_to_user(struct _fpstate __user *buf,
				       struct pt_regs *regs)
{
	return(CHOOSE_MODE(convert_fxsr_to_user_tt(buf, regs), 0));
}

static inline int convert_fxsr_from_user(struct pt_regs *regs, 
					 struct _fpstate __user *buf)
{
	return(CHOOSE_MODE(convert_fxsr_from_user_tt(regs, buf), 0));
}

int get_fpregs(unsigned long buf, struct task_struct *child)
{
	int err;

	err = convert_fxsr_to_user((struct _fpstate __user *) buf,
				   &child->thread.regs);
	if(err) return(-EFAULT);
	else return(0);
}

int set_fpregs(unsigned long buf, struct task_struct *child)
{
	int err;

	err = convert_fxsr_from_user(&child->thread.regs, 
				     (struct _fpstate __user *) buf);
	if(err) return(-EFAULT);
	else return(0);
}

int get_fpxregs(unsigned long buf, struct task_struct *tsk)
{
	return(CHOOSE_MODE(get_fpxregs_tt(buf, tsk), 0));
}

int set_fpxregs(unsigned long buf, struct task_struct *tsk)
{
	return(CHOOSE_MODE(set_fpxregs_tt(buf, tsk), 0));
}

#ifdef notdef
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
{
	fpu->cwd = (((SC_FP_CW(PT_REGS_SC(regs)) & 0xffff) << 16) |
		    (SC_FP_SW(PT_REGS_SC(regs)) & 0xffff));
	fpu->swd = SC_FP_CSSEL(PT_REGS_SC(regs)) & 0xffff;
	fpu->twd = SC_FP_IPOFF(PT_REGS_SC(regs));
	fpu->fip = SC_FP_CSSEL(PT_REGS_SC(regs)) & 0xffff;
	fpu->fcs = SC_FP_DATAOFF(PT_REGS_SC(regs));
	fpu->foo = SC_FP_DATASEL(PT_REGS_SC(regs));
	fpu->fos = 0;
	memcpy(fpu->st_space, (void *) SC_FP_ST(PT_REGS_SC(regs)),
	       sizeof(fpu->st_space));
	return(1);
}
#endif

static inline void copy_fpu_fxsave(struct pt_regs *regs,
				   struct user_i387_struct *buf)
{
	(void) CHOOSE_MODE(copy_fpu_fxsave_tt(regs, buf), 0);
}

int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu )
{
	copy_fpu_fxsave(regs, (struct user_i387_struct *) fpu);
	return(1);
}

/*
 * Overrides for Emacs so that we follow Linus's tabbing style.
 * Emacs will notice this stuff at the end of the file and automatically
 * adjust the settings for this buffer only.  This must remain at the end
 * of the file.
 * ---------------------------------------------------------------------------
 * Local variables:
 * c-file-style: "linux"
 * End:
 */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
	3	* Licensed under the GPL
	4	*/
	5
1da177e4 LT	6	#include <linux/compiler.h>
1da177e4 LT	7	#include "linux/sched.h"
81efcd33	8	#include "linux/mm.h"
1da177e4 LT	9	#include "asm/elf.h"
	10	#include "asm/ptrace.h"
	11	#include "asm/uaccess.h"
	12	#include "asm/unistd.h"
	13	#include "sysdep/ptrace.h"
	14	#include "sysdep/sigcontext.h"
	15	#include "sysdep/sc.h"
	16
972410b0	17	void arch_switch_to_skas(struct task_struct from, struct task_struct to)
1da177e4	18	{
54d8d3b5 PBG	19	int err = arch_switch_tls_skas(from, to);
	20	if (!err)
	21	return;
	22
	23	if (err != -EINVAL)
	24	printk(KERN_WARNING "arch_switch_tls_skas failed, errno %d, not EINVAL\n", -err);
	25	else
	26	printk(KERN_WARNING "arch_switch_tls_skas failed, errno = EINVAL\n");
1da177e4 LT	27	}
	28
	29	int is_syscall(unsigned long addr)
	30	{
	31	unsigned short instr;
	32	int n;
	33
	34	n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
	35	if(n){
81efcd33 BS	36	/* access_process_vm() grants access to vsyscall and stub,
	37	* while copy_from_user doesn't. Maybe access_process_vm is
	38	* slow, but that doesn't matter, since it will be called only
	39	* in case of singlestepping, if copy_from_user failed.
	40	*/
	41	n = access_process_vm(current, addr, &instr, sizeof(instr), 0);
	42	if(n != sizeof(instr)) {
	43	printk("is_syscall : failed to read instruction from "
	44	"0x%lx\n", addr);
	45	return(1);
	46	}
1da177e4 LT	47	}
	48	/* int 0x80 or sysenter */
	49	return((instr == 0x80cd) \|\| (instr == 0x340f));
	50	}
	51
	52	/* determines which flags the user has access to. */
	53	/* 1 = access 0 = no access */
	54	#define FLAG_MASK 0x00044dd5
	55
	56	int putreg(struct task_struct *child, int regno, unsigned long value)
	57	{
	58	regno >>= 2;
	59	switch (regno) {
	60	case FS:
	61	if (value && (value & 3) != 3)
	62	return -EIO;
	63	PT_REGS_FS(&child->thread.regs) = value;
	64	return 0;
	65	case GS:
	66	if (value && (value & 3) != 3)
	67	return -EIO;
	68	PT_REGS_GS(&child->thread.regs) = value;
	69	return 0;
	70	case DS:
	71	case ES:
	72	if (value && (value & 3) != 3)
	73	return -EIO;
	74	value &= 0xffff;
	75	break;
	76	case SS:
	77	case CS:
	78	if ((value & 3) != 3)
	79	return -EIO;
	80	value &= 0xffff;
	81	break;
	82	case EFL:
	83	value &= FLAG_MASK;
	84	value \|= PT_REGS_EFLAGS(&child->thread.regs);
	85	break;
	86	}
	87	PT_REGS_SET(&child->thread.regs, regno, value);
	88	return 0;
	89	}
	90
82c1c11b BS	91	int poke_user(struct task_struct *child, long addr, long data)
	92	{
	93	if ((addr & 3) \|\| addr < 0)
	94	return -EIO;
	95
	96	if (addr < MAX_REG_OFFSET)
	97	return putreg(child, addr, data);
	98
	99	else if((addr >= offsetof(struct user, u_debugreg[0])) &&
	100	(addr <= offsetof(struct user, u_debugreg[7]))){
	101	addr -= offsetof(struct user, u_debugreg[0]);
	102	addr = addr >> 2;
	103	if((addr == 4) \|\| (addr == 5)) return -EIO;
	104	child->thread.arch.debugregs[addr] = data;
	105	return 0;
	106	}
	107	return -EIO;
	108	}
	109
1da177e4 LT	110	unsigned long getreg(struct task_struct *child, int regno)
	111	{
	112	unsigned long retval = ~0UL;
	113
	114	regno >>= 2;
	115	switch (regno) {
	116	case FS:
	117	case GS:
	118	case DS:
	119	case ES:
	120	case SS:
	121	case CS:
	122	retval = 0xffff;
	123	/* fall through */
	124	default:
	125	retval &= PT_REG(&child->thread.regs, regno);
	126	}
	127	return retval;
	128	}
	129
82c1c11b BS	130	int peek_user(struct task_struct *child, long addr, long data)
	131	{
	132	/* read the word at location addr in the USER area. */
4d338e1a	133	unsigned long tmp;
82c1c11b	134
4d338e1a AV	135	if ((addr & 3) \|\| addr < 0)
4d338e1a AV	136	return -EIO;
82c1c11b	137
4d338e1a AV	138	tmp = 0; /* Default return condition */
	139	if(addr < MAX_REG_OFFSET){
	140	tmp = getreg(child, addr);
	141	}
	142	else if((addr >= offsetof(struct user, u_debugreg[0])) &&
	143	(addr <= offsetof(struct user, u_debugreg[7]))){
	144	addr -= offsetof(struct user, u_debugreg[0]);
	145	addr = addr >> 2;
	146	tmp = child->thread.arch.debugregs[addr];
	147	}
	148	return put_user(tmp, (unsigned long __user *) data);
82c1c11b BS	149	}
82c1c11b BS	150
1da177e4 LT	151	struct i387_fxsave_struct {
	152	unsigned short cwd;
	153	unsigned short swd;
	154	unsigned short twd;
	155	unsigned short fop;
	156	long fip;
	157	long fcs;
	158	long foo;
	159	long fos;
	160	long mxcsr;
	161	long reserved;
	162	long st_space[32]; /* 816 bytes for each FP-reg = 128 bytes /
	163	long xmm_space[32]; /* 816 bytes for each XMM-reg = 128 bytes /
	164	long padding[56];
	165	};
	166
	167	/*
	168	* FPU tag word conversions.
	169	*/
	170
	171	static inline unsigned short twd_i387_to_fxsr( unsigned short twd )
	172	{
	173	unsigned int tmp; /* to avoid 16 bit prefixes in the code */
	174
	175	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
	176	tmp = ~twd;
	177	tmp = (tmp \| (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
	178	/* and move the valid bits to the lower byte. */
	179	tmp = (tmp \| (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
	180	tmp = (tmp \| (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
	181	tmp = (tmp \| (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
	182	return tmp;
	183	}
	184
	185	static inline unsigned long twd_fxsr_to_i387( struct i387_fxsave_struct *fxsave )
	186	{
	187	struct _fpxreg *st = NULL;
	188	unsigned long twd = (unsigned long) fxsave->twd;
	189	unsigned long tag;
	190	unsigned long ret = 0xffff0000;
	191	int i;
	192
	193	#define FPREG_ADDR(f, n) ((char )&(f)->st_space + (n) 16);
	194
	195	for ( i = 0 ; i < 8 ; i++ ) {
	196	if ( twd & 0x1 ) {
	197	st = (struct _fpxreg *) FPREG_ADDR( fxsave, i );
	198
	199	switch ( st->exponent & 0x7fff ) {
	200	case 0x7fff:
	201	tag = 2; /* Special */
	202	break;
	203	case 0x0000:
	204	if ( !st->significand[0] &&
	205	!st->significand[1] &&
	206	!st->significand[2] &&
	207	!st->significand[3] ) {
	208	tag = 1; /* Zero */
	209	} else {
	210	tag = 2; /* Special */
	211	}
	212	break;
	213	default:
	214	if ( st->significand[3] & 0x8000 ) {
215	tag = 0; /* Valid */
216	} else {
217	tag = 2; /* Special */
218	}
219	break;
220	}
221	} else {
222	tag = 3; /* Empty */
223	}
224	ret \|= (tag << (2 * i));
225	twd = twd >> 1;
226	}
227	return ret;
228	}
229
1da177e4 LT	230	static inline int convert_fxsr_to_user(struct _fpstate __user *buf,
	231	struct pt_regs *regs)
	232	{
	233	return(CHOOSE_MODE(convert_fxsr_to_user_tt(buf, regs), 0));
	234	}
	235
1da177e4 LT	236	static inline int convert_fxsr_from_user(struct pt_regs *regs,
	237	struct _fpstate __user *buf)
	238	{
	239	return(CHOOSE_MODE(convert_fxsr_from_user_tt(regs, buf), 0));
	240	}
	241
	242	int get_fpregs(unsigned long buf, struct task_struct *child)
	243	{
	244	int err;
	245
	246	err = convert_fxsr_to_user((struct _fpstate __user *) buf,
	247	&child->thread.regs);
	248	if(err) return(-EFAULT);
	249	else return(0);
	250	}
	251
	252	int set_fpregs(unsigned long buf, struct task_struct *child)
	253	{
	254	int err;
	255
	256	err = convert_fxsr_from_user(&child->thread.regs,
	257	(struct _fpstate __user *) buf);
	258	if(err) return(-EFAULT);
	259	else return(0);
	260	}
	261
1da177e4 LT	262	int get_fpxregs(unsigned long buf, struct task_struct *tsk)
	263	{
	264	return(CHOOSE_MODE(get_fpxregs_tt(buf, tsk), 0));
	265	}
	266
1da177e4 LT	267	int set_fpxregs(unsigned long buf, struct task_struct *tsk)
	268	{
	269	return(CHOOSE_MODE(set_fpxregs_tt(buf, tsk), 0));
	270	}
	271
	272	#ifdef notdef
	273	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpu)
	274	{
	275	fpu->cwd = (((SC_FP_CW(PT_REGS_SC(regs)) & 0xffff) << 16) \|
	276	(SC_FP_SW(PT_REGS_SC(regs)) & 0xffff));
	277	fpu->swd = SC_FP_CSSEL(PT_REGS_SC(regs)) & 0xffff;
	278	fpu->twd = SC_FP_IPOFF(PT_REGS_SC(regs));
	279	fpu->fip = SC_FP_CSSEL(PT_REGS_SC(regs)) & 0xffff;
	280	fpu->fcs = SC_FP_DATAOFF(PT_REGS_SC(regs));
	281	fpu->foo = SC_FP_DATASEL(PT_REGS_SC(regs));
	282	fpu->fos = 0;
	283	memcpy(fpu->st_space, (void *) SC_FP_ST(PT_REGS_SC(regs)),
	284	sizeof(fpu->st_space));
	285	return(1);
	286	}
	287	#endif
	288
1da177e4 LT	289	static inline void copy_fpu_fxsave(struct pt_regs *regs,
	290	struct user_i387_struct *buf)
	291	{
	292	(void) CHOOSE_MODE(copy_fpu_fxsave_tt(regs, buf), 0);
	293	}
	294
	295	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpu )
	296	{
	297	copy_fpu_fxsave(regs, (struct user_i387_struct *) fpu);
	298	return(1);
	299	}
	300
	301	/*
	302	* Overrides for Emacs so that we follow Linus's tabbing style.
	303	* Emacs will notice this stuff at the end of the file and automatically
	304	* adjust the settings for this buffer only. This must remain at the end
	305	* of the file.
	306	* ---------------------------------------------------------------------------
	307	* Local variables:
	308	* c-file-style: "linux"
	309	* End:
	310	*/