[linux-2.6-block.git] / arch / x86 / um / signal.c

/*
 * Copyright (C) 2003 PathScale, Inc.
 * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 * Licensed under the GPL
 */


#include <linux/personality.h>
#include <linux/ptrace.h>
#include <linux/kernel.h>
#include <asm/unistd.h>
#include <linux/uaccess.h>
#include <asm/ucontext.h>
#include <frame_kern.h>
#include <registers.h>
#include <skas.h>

#ifdef CONFIG_X86_32

/*
 * 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 user_fxsr_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 int convert_fxsr_to_user(struct _fpstate __user *buf,
				struct user_fxsr_struct *fxsave)
{
	unsigned long env[7];
	struct _fpreg __user *to;
	struct _fpxreg *from;
	int i;

	env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul;
	env[1] = (unsigned long)fxsave->swd | 0xffff0000ul;
	env[2] = twd_fxsr_to_i387(fxsave);
	env[3] = fxsave->fip;
	env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16);
	env[5] = fxsave->foo;
	env[6] = fxsave->fos;

	if (__copy_to_user(buf, env, 7 * sizeof(unsigned long)))
		return 1;

	to = &buf->_st[0];
	from = (struct _fpxreg *) &fxsave->st_space[0];
	for (i = 0; i < 8; i++, to++, from++) {
		unsigned long __user *t = (unsigned long __user *)to;
		unsigned long *f = (unsigned long *)from;

		if (__put_user(*f, t) ||
				__put_user(*(f + 1), t + 1) ||
				__put_user(from->exponent, &to->exponent))
			return 1;
	}
	return 0;
}

static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave,
				  struct _fpstate __user *buf)
{
	unsigned long env[7];
	struct _fpxreg *to;
	struct _fpreg __user *from;
	int i;

	if (copy_from_user( env, buf, 7 * sizeof(long)))
		return 1;

	fxsave->cwd = (unsigned short)(env[0] & 0xffff);
	fxsave->swd = (unsigned short)(env[1] & 0xffff);
	fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff));
	fxsave->fip = env[3];
	fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16);
	fxsave->fcs = (env[4] & 0xffff);
	fxsave->foo = env[5];
	fxsave->fos = env[6];

	to = (struct _fpxreg *) &fxsave->st_space[0];
	from = &buf->_st[0];
	for (i = 0; i < 8; i++, to++, from++) {
		unsigned long *t = (unsigned long *)to;
		unsigned long __user *f = (unsigned long __user *)from;

		if (__get_user(*t, f) ||
		    __get_user(*(t + 1), f + 1) ||
		    __get_user(to->exponent, &from->exponent))
			return 1;
	}
	return 0;
}

extern int have_fpx_regs;

#endif

static int copy_sc_from_user(struct pt_regs *regs,
			     struct sigcontext __user *from)
{
	struct sigcontext sc;
	int err, pid;

	/* Always make any pending restarted system calls return -EINTR */
	current->restart_block.fn = do_no_restart_syscall;

	err = copy_from_user(&sc, from, sizeof(sc));
	if (err)
		return err;

#define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname

#ifdef CONFIG_X86_32
	GETREG(GS, gs);
	GETREG(FS, fs);
	GETREG(ES, es);
	GETREG(DS, ds);
#endif
	GETREG(DI, di);
	GETREG(SI, si);
	GETREG(BP, bp);
	GETREG(SP, sp);
	GETREG(BX, bx);
	GETREG(DX, dx);
	GETREG(CX, cx);
	GETREG(AX, ax);
	GETREG(IP, ip);

#ifdef CONFIG_X86_64
	GETREG(R8, r8);
	GETREG(R9, r9);
	GETREG(R10, r10);
	GETREG(R11, r11);
	GETREG(R12, r12);
	GETREG(R13, r13);
	GETREG(R14, r14);
	GETREG(R15, r15);
#endif

	GETREG(CS, cs);
	GETREG(EFLAGS, flags);
#ifdef CONFIG_X86_32
	GETREG(SS, ss);
#endif

#undef GETREG

	pid = userspace_pid[current_thread_info()->cpu];
#ifdef CONFIG_X86_32
	if (have_fpx_regs) {
		struct user_fxsr_struct fpx;

		err = copy_from_user(&fpx,
			&((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0],
				     sizeof(struct user_fxsr_struct));
		if (err)
			return 1;

		err = convert_fxsr_from_user(&fpx, (void *)sc.fpstate);
		if (err)
			return 1;

		err = restore_fpx_registers(pid, (unsigned long *) &fpx);
		if (err < 0) {
			printk(KERN_ERR "copy_sc_from_user - "
			       "restore_fpx_registers failed, errno = %d\n",
			       -err);
			return 1;
		}
	} else
#endif
	{
		err = copy_from_user(regs->regs.fp, (void *)sc.fpstate,
				     sizeof(struct _xstate));
		if (err)
			return 1;
	}
	return 0;
}

static int copy_sc_to_user(struct sigcontext __user *to,
			   struct _xstate __user *to_fp, struct pt_regs *regs,
			   unsigned long mask)
{
	struct sigcontext sc;
	struct faultinfo * fi = &current->thread.arch.faultinfo;
	int err, pid;
	memset(&sc, 0, sizeof(struct sigcontext));

#define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]

#ifdef CONFIG_X86_32
	PUTREG(GS, gs);
	PUTREG(FS, fs);
	PUTREG(ES, es);
	PUTREG(DS, ds);
#endif
	PUTREG(DI, di);
	PUTREG(SI, si);
	PUTREG(BP, bp);
	PUTREG(SP, sp);
	PUTREG(BX, bx);
	PUTREG(DX, dx);
	PUTREG(CX, cx);
	PUTREG(AX, ax);
#ifdef CONFIG_X86_64
	PUTREG(R8, r8);
	PUTREG(R9, r9);
	PUTREG(R10, r10);
	PUTREG(R11, r11);
	PUTREG(R12, r12);
	PUTREG(R13, r13);
	PUTREG(R14, r14);
	PUTREG(R15, r15);
#endif

	sc.cr2 = fi->cr2;
	sc.err = fi->error_code;
	sc.trapno = fi->trap_no;
	PUTREG(IP, ip);
	PUTREG(CS, cs);
	PUTREG(EFLAGS, flags);
#ifdef CONFIG_X86_32
	PUTREG(SP, sp_at_signal);
	PUTREG(SS, ss);
#endif
#undef PUTREG
	sc.oldmask = mask;
	sc.fpstate = (unsigned long)to_fp;

	err = copy_to_user(to, &sc, sizeof(struct sigcontext));
	if (err)
		return 1;

	pid = userspace_pid[current_thread_info()->cpu];

#ifdef CONFIG_X86_32
	if (have_fpx_regs) {
		struct user_fxsr_struct fpx;

		err = save_fpx_registers(pid, (unsigned long *) &fpx);
		if (err < 0){
			printk(KERN_ERR "copy_sc_to_user - save_fpx_registers "
			       "failed, errno = %d\n", err);
			return 1;
		}

		err = convert_fxsr_to_user(&to_fp->fpstate, &fpx);
		if (err)
			return 1;

		err |= __put_user(fpx.swd, &to_fp->fpstate.status);
		err |= __put_user(X86_FXSR_MAGIC, &to_fp->fpstate.magic);
		if (err)
			return 1;

		if (copy_to_user(&to_fp->fpstate._fxsr_env[0], &fpx,
				 sizeof(struct user_fxsr_struct)))
			return 1;
	} else
#endif
	{
		if (copy_to_user(to_fp, regs->regs.fp, sizeof(struct _xstate)))
			return 1;
	}

	return 0;
}

#ifdef CONFIG_X86_32
static int copy_ucontext_to_user(struct ucontext __user *uc,
				 struct _xstate __user *fp, sigset_t *set,
				 unsigned long sp)
{
	int err = 0;

	err |= __save_altstack(&uc->uc_stack, sp);
	err |= copy_sc_to_user(&uc->uc_mcontext, fp, &current->thread.regs, 0);
	err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
	return err;
}

struct sigframe
{
	char __user *pretcode;
	int sig;
	struct sigcontext sc;
	struct _xstate fpstate;
	unsigned long extramask[_NSIG_WORDS-1];
	char retcode[8];
};

struct rt_sigframe
{
	char __user *pretcode;
	int sig;
	struct siginfo __user *pinfo;
	void __user *puc;
	struct siginfo info;
	struct ucontext uc;
	struct _xstate fpstate;
	char retcode[8];
};

int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig,
			  struct pt_regs *regs, sigset_t *mask)
{
	struct sigframe __user *frame;
	void __user *restorer;
	int err = 0, sig = ksig->sig;

	/* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
	stack_top = ((stack_top + 4) & -16UL) - 4;
	frame = (struct sigframe __user *) stack_top - 1;
	if (!access_ok(frame, sizeof(*frame)))
		return 1;

	restorer = frame->retcode;
	if (ksig->ka.sa.sa_flags & SA_RESTORER)
		restorer = ksig->ka.sa.sa_restorer;

	err |= __put_user(restorer, &frame->pretcode);
	err |= __put_user(sig, &frame->sig);
	err |= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
	if (_NSIG_WORDS > 1)
		err |= __copy_to_user(&frame->extramask, &mask->sig[1],
				      sizeof(frame->extramask));

	/*
	 * This is popl %eax ; movl $,%eax ; int $0x80
	 *
	 * WE DO NOT USE IT ANY MORE! It's only left here for historical
	 * reasons and because gdb uses it as a signature to notice
	 * signal handler stack frames.
	 */
	err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
	err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
	err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));

	if (err)
		return err;

	PT_REGS_SP(regs) = (unsigned long) frame;
	PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
	PT_REGS_AX(regs) = (unsigned long) sig;
	PT_REGS_DX(regs) = (unsigned long) 0;
	PT_REGS_CX(regs) = (unsigned long) 0;
	return 0;
}

int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
			  struct pt_regs *regs, sigset_t *mask)
{
	struct rt_sigframe __user *frame;
	void __user *restorer;
	int err = 0, sig = ksig->sig;

	stack_top &= -8UL;
	frame = (struct rt_sigframe __user *) stack_top - 1;
	if (!access_ok(frame, sizeof(*frame)))
		return 1;

	restorer = frame->retcode;
	if (ksig->ka.sa.sa_flags & SA_RESTORER)
		restorer = ksig->ka.sa.sa_restorer;

	err |= __put_user(restorer, &frame->pretcode);
	err |= __put_user(sig, &frame->sig);
	err |= __put_user(&frame->info, &frame->pinfo);
	err |= __put_user(&frame->uc, &frame->puc);
	err |= copy_siginfo_to_user(&frame->info, &ksig->info);
	err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
					PT_REGS_SP(regs));

	/*
	 * This is movl $,%eax ; int $0x80
	 *
	 * WE DO NOT USE IT ANY MORE! It's only left here for historical
	 * reasons and because gdb uses it as a signature to notice
	 * signal handler stack frames.
	 */
	err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
	err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
	err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));

	if (err)
		return err;

	PT_REGS_SP(regs) = (unsigned long) frame;
	PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
	PT_REGS_AX(regs) = (unsigned long) sig;
	PT_REGS_DX(regs) = (unsigned long) &frame->info;
	PT_REGS_CX(regs) = (unsigned long) &frame->uc;
	return 0;
}

long sys_sigreturn(void)
{
	unsigned long sp = PT_REGS_SP(&current->thread.regs);
	struct sigframe __user *frame = (struct sigframe __user *)(sp - 8);
	sigset_t set;
	struct sigcontext __user *sc = &frame->sc;
	int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);

	if (copy_from_user(&set.sig[0], &sc->oldmask, sizeof(set.sig[0])) ||
	    copy_from_user(&set.sig[1], frame->extramask, sig_size))
		goto segfault;

	set_current_blocked(&set);

	if (copy_sc_from_user(&current->thread.regs, sc))
		goto segfault;

	/* Avoid ERESTART handling */
	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
	return PT_REGS_SYSCALL_RET(&current->thread.regs);

 segfault:
	force_sig(SIGSEGV);
	return 0;
}

#else

struct rt_sigframe
{
	char __user *pretcode;
	struct ucontext uc;
	struct siginfo info;
	struct _xstate fpstate;
};

int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
			  struct pt_regs *regs, sigset_t *set)
{
	struct rt_sigframe __user *frame;
	int err = 0, sig = ksig->sig;
	unsigned long fp_to;

	frame = (struct rt_sigframe __user *)
		round_down(stack_top - sizeof(struct rt_sigframe), 16);
	/* Subtract 128 for a red zone and 8 for proper alignment */
	frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);

	if (!access_ok(frame, sizeof(*frame)))
		goto out;

	if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
		err |= copy_siginfo_to_user(&frame->info, &ksig->info);
		if (err)
			goto out;
	}

	/* Create the ucontext.  */
	err |= __put_user(0, &frame->uc.uc_flags);
	err |= __put_user(0, &frame->uc.uc_link);
	err |= __save_altstack(&frame->uc.uc_stack, PT_REGS_SP(regs));
	err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
			       set->sig[0]);

	fp_to = (unsigned long)&frame->fpstate;

	err |= __put_user(fp_to, &frame->uc.uc_mcontext.fpstate);
	if (sizeof(*set) == 16) {
		err |= __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
		err |= __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
	}
	else
		err |= __copy_to_user(&frame->uc.uc_sigmask, set,
				      sizeof(*set));

	/*
	 * Set up to return from userspace.  If provided, use a stub
	 * already in userspace.
	 */
	/* x86-64 should always use SA_RESTORER. */
	if (ksig->ka.sa.sa_flags & SA_RESTORER)
		err |= __put_user((void *)ksig->ka.sa.sa_restorer,
				  &frame->pretcode);
	else
		/* could use a vstub here */
		return err;

	if (err)
		return err;

	PT_REGS_SP(regs) = (unsigned long) frame;
	PT_REGS_DI(regs) = sig;
	/* In case the signal handler was declared without prototypes */
	PT_REGS_AX(regs) = 0;

	/*
	 * This also works for non SA_SIGINFO handlers because they expect the
	 * next argument after the signal number on the stack.
	 */
	PT_REGS_SI(regs) = (unsigned long) &frame->info;
	PT_REGS_DX(regs) = (unsigned long) &frame->uc;
	PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
 out:
	return err;
}
#endif

long sys_rt_sigreturn(void)
{
	unsigned long sp = PT_REGS_SP(&current->thread.regs);
	struct rt_sigframe __user *frame =
		(struct rt_sigframe __user *)(sp - sizeof(long));
	struct ucontext __user *uc = &frame->uc;
	sigset_t set;

	if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
		goto segfault;

	set_current_blocked(&set);

	if (copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
		goto segfault;

	/* Avoid ERESTART handling */
	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
	return PT_REGS_SYSCALL_RET(&current->thread.regs);

 segfault:
	force_sig(SIGSEGV);
	return 0;
}
Commit	Line	Data
1da177e4	1	/*
f67aa2ff AV	2	* Copyright (C) 2003 PathScale, Inc.
f67aa2ff AV	3	* Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
1da177e4 LT	4	* Licensed under the GPL
	5	*/
	6
f67aa2ff AV	7
f67aa2ff AV	8	#include <linux/personality.h>
7796931f	9	#include <linux/ptrace.h>
f67aa2ff	10	#include <linux/kernel.h>
7796931f	11	#include <asm/unistd.h>
7c0f6ba6	12	#include <linux/uaccess.h>
7796931f	13	#include <asm/ucontext.h>
37185b33	14	#include <frame_kern.h>
dbba7f70	15	#include <registers.h>
37185b33	16	#include <skas.h>
1da177e4	17
f67aa2ff AV	18	#ifdef CONFIG_X86_32
f67aa2ff AV	19
a5f6096c JD	20	/*
	21	* FPU tag word conversions.
	22	*/
	23
	24	static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
	25	{
	26	unsigned int tmp; /* to avoid 16 bit prefixes in the code */
	27
	28	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
	29	tmp = ~twd;
	30	tmp = (tmp \| (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
	31	/* and move the valid bits to the lower byte. */
	32	tmp = (tmp \| (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
	33	tmp = (tmp \| (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
	34	tmp = (tmp \| (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
	35	return tmp;
	36	}
	37
	38	static inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave)
	39	{
	40	struct _fpxreg *st = NULL;
	41	unsigned long twd = (unsigned long) fxsave->twd;
	42	unsigned long tag;
	43	unsigned long ret = 0xffff0000;
	44	int i;
	45
497888cf	46	#define FPREG_ADDR(f, n) ((char )&(f)->st_space + (n) 16)
a5f6096c JD	47
	48	for (i = 0; i < 8; i++) {
	49	if (twd & 0x1) {
	50	st = (struct _fpxreg *) FPREG_ADDR(fxsave, i);
	51
	52	switch (st->exponent & 0x7fff) {
	53	case 0x7fff:
	54	tag = 2; /* Special */
	55	break;
	56	case 0x0000:
	57	if ( !st->significand[0] &&
	58	!st->significand[1] &&
	59	!st->significand[2] &&
	60	!st->significand[3] ) {
	61	tag = 1; /* Zero */
	62	} else {
	63	tag = 2; /* Special */
	64	}
	65	break;
	66	default:
	67	if (st->significand[3] & 0x8000) {
	68	tag = 0; /* Valid */
	69	} else {
	70	tag = 2; /* Special */
	71	}
	72	break;
	73	}
	74	} else {
	75	tag = 3; /* Empty */
	76	}
	77	ret \|= (tag << (2 * i));
	78	twd = twd >> 1;
	79	}
	80	return ret;
	81	}
	82
	83	static int convert_fxsr_to_user(struct _fpstate __user *buf,
	84	struct user_fxsr_struct *fxsave)
	85	{
	86	unsigned long env[7];
	87	struct _fpreg __user *to;
	88	struct _fpxreg *from;
	89	int i;
	90
	91	env[0] = (unsigned long)fxsave->cwd \| 0xffff0000ul;
	92	env[1] = (unsigned long)fxsave->swd \| 0xffff0000ul;
	93	env[2] = twd_fxsr_to_i387(fxsave);
	94	env[3] = fxsave->fip;
	95	env[4] = fxsave->fcs \| ((unsigned long)fxsave->fop << 16);
	96	env[5] = fxsave->foo;
	97	env[6] = fxsave->fos;
	98
	99	if (__copy_to_user(buf, env, 7 * sizeof(unsigned long)))
	100	return 1;
	101
	102	to = &buf->_st[0];
	103	from = (struct _fpxreg *) &fxsave->st_space[0];
	104	for (i = 0; i < 8; i++, to++, from++) {
	105	unsigned long __user t = (unsigned long __user )to;
	106	unsigned long f = (unsigned long )from;
	107
	108	if (__put_user(*f, t) \|\|
	109	__put_user(*(f + 1), t + 1) \|\|
	110	__put_user(from->exponent, &to->exponent))
111	return 1;
112	}
113	return 0;
114	}
115
116	static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave,
117	struct _fpstate __user *buf)
118	{
119	unsigned long env[7];
120	struct _fpxreg *to;
121	struct _fpreg __user *from;
122	int i;
123
124	if (copy_from_user( env, buf, 7 * sizeof(long)))
125	return 1;
126
127	fxsave->cwd = (unsigned short)(env[0] & 0xffff);
128	fxsave->swd = (unsigned short)(env[1] & 0xffff);
129	fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff));
130	fxsave->fip = env[3];
131	fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16);
132	fxsave->fcs = (env[4] & 0xffff);
133	fxsave->foo = env[5];
134	fxsave->fos = env[6];
135
136	to = (struct _fpxreg *) &fxsave->st_space[0];
137	from = &buf->_st[0];
138	for (i = 0; i < 8; i++, to++, from++) {
139	unsigned long t = (unsigned long )to;
140	unsigned long __user f = (unsigned long __user )from;
141
142	if (__get_user(*t, f) \|\|
143	__get_user(*(t + 1), f + 1) \|\|
144	__get_user(to->exponent, &from->exponent))
145	return 1;
146	}
147	return 0;
148	}
149
150	extern int have_fpx_regs;
151
f67aa2ff AV	152	#endif
f67aa2ff AV	153
77bf4400 JD	154	static int copy_sc_from_user(struct pt_regs *regs,
77bf4400 JD	155	struct sigcontext __user *from)
1da177e4	156	{
a5f6096c	157	struct sigcontext sc;
a5a678c8	158	int err, pid;
1da177e4	159
3b7d15bd	160	/* Always make any pending restarted system calls return -EINTR */
f56141e3	161	current->restart_block.fn = do_no_restart_syscall;
3b7d15bd	162
1da177e4	163	err = copy_from_user(&sc, from, sizeof(sc));
ba180fd4	164	if (err)
5d86456d	165	return err;
1da177e4	166
a955bd61 AV	167	#define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname
a955bd61 AV	168
f67aa2ff	169	#ifdef CONFIG_X86_32
a955bd61 AV	170	GETREG(GS, gs);
	171	GETREG(FS, fs);
	172	GETREG(ES, es);
	173	GETREG(DS, ds);
f67aa2ff	174	#endif
3579a389 AV	175	GETREG(DI, di);
	176	GETREG(SI, si);
	177	GETREG(BP, bp);
a955bd61	178	GETREG(SP, sp);
3579a389 AV	179	GETREG(BX, bx);
	180	GETREG(DX, dx);
	181	GETREG(CX, cx);
	182	GETREG(AX, ax);
a955bd61	183	GETREG(IP, ip);
f67aa2ff AV	184
	185	#ifdef CONFIG_X86_64
	186	GETREG(R8, r8);
	187	GETREG(R9, r9);
	188	GETREG(R10, r10);
	189	GETREG(R11, r11);
	190	GETREG(R12, r12);
	191	GETREG(R13, r13);
	192	GETREG(R14, r14);
	193	GETREG(R15, r15);
	194	#endif
	195
a955bd61 AV	196	GETREG(CS, cs);
a955bd61 AV	197	GETREG(EFLAGS, flags);
f67aa2ff	198	#ifdef CONFIG_X86_32
a955bd61	199	GETREG(SS, ss);
f67aa2ff	200	#endif
a955bd61 AV	201
a955bd61 AV	202	#undef GETREG
f67aa2ff AV	203
	204	pid = userspace_pid[current_thread_info()->cpu];
	205	#ifdef CONFIG_X86_32
a5f6096c JD	206	if (have_fpx_regs) {
a5f6096c JD	207	struct user_fxsr_struct fpx;
1da177e4	208
966c8079 WC	209	err = copy_from_user(&fpx,
966c8079 WC	210	&((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0],
a5f6096c JD	211	sizeof(struct user_fxsr_struct));
	212	if (err)
	213	return 1;
	214
8090bfd2	215	err = convert_fxsr_from_user(&fpx, (void *)sc.fpstate);
a5f6096c JD	216	if (err)
	217	return 1;
	218
a5a678c8	219	err = restore_fpx_registers(pid, (unsigned long *) &fpx);
a5f6096c JD	220	if (err < 0) {
	221	printk(KERN_ERR "copy_sc_from_user - "
	222	"restore_fpx_registers failed, errno = %d\n",
	223	-err);
	224	return 1;
	225	}
f67aa2ff AV	226	} else
	227	#endif
	228	{
6de5a8a5	229	err = copy_from_user(regs->regs.fp, (void *)sc.fpstate,
b6024b21	230	sizeof(struct _xstate));
a5f6096c JD	231	if (err)
a5f6096c JD	232	return 1;
1da177e4	233	}
5d86456d	234	return 0;
1da177e4 LT	235	}
1da177e4 LT	236
77bf4400	237	static int copy_sc_to_user(struct sigcontext __user *to,
b6024b21	238	struct _xstate __user to_fp, struct pt_regs regs,
f67aa2ff	239	unsigned long mask)
1da177e4	240	{
ba180fd4	241	struct sigcontext sc;
c578455a	242	struct faultinfo * fi = &current->thread.arch.faultinfo;
a5a678c8	243	int err, pid;
a955bd61	244	memset(&sc, 0, sizeof(struct sigcontext));
1da177e4	245
f67aa2ff AV	246	#define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]
	247
	248	#ifdef CONFIG_X86_32
	249	PUTREG(GS, gs);
	250	PUTREG(FS, fs);
	251	PUTREG(ES, es);
	252	PUTREG(DS, ds);
	253	#endif
	254	PUTREG(DI, di);
	255	PUTREG(SI, si);
	256	PUTREG(BP, bp);
	257	PUTREG(SP, sp);
	258	PUTREG(BX, bx);
	259	PUTREG(DX, dx);
	260	PUTREG(CX, cx);
	261	PUTREG(AX, ax);
	262	#ifdef CONFIG_X86_64
	263	PUTREG(R8, r8);
	264	PUTREG(R9, r9);
	265	PUTREG(R10, r10);
	266	PUTREG(R11, r11);
	267	PUTREG(R12, r12);
	268	PUTREG(R13, r13);
	269	PUTREG(R14, r14);
	270	PUTREG(R15, r15);
	271	#endif
	272
ba180fd4 JD	273	sc.cr2 = fi->cr2;
	274	sc.err = fi->error_code;
	275	sc.trapno = fi->trap_no;
f67aa2ff AV	276	PUTREG(IP, ip);
	277	PUTREG(CS, cs);
	278	PUTREG(EFLAGS, flags);
	279	#ifdef CONFIG_X86_32
	280	PUTREG(SP, sp_at_signal);
	281	PUTREG(SS, ss);
	282	#endif
	283	#undef PUTREG
	284	sc.oldmask = mask;
8090bfd2	285	sc.fpstate = (unsigned long)to_fp;
1da177e4	286
f67aa2ff AV	287	err = copy_to_user(to, &sc, sizeof(struct sigcontext));
	288	if (err)
	289	return 1;
	290
a5a678c8	291	pid = userspace_pid[current_thread_info()->cpu];
f67aa2ff AV	292
f67aa2ff AV	293	#ifdef CONFIG_X86_32
a5f6096c JD	294	if (have_fpx_regs) {
	295	struct user_fxsr_struct fpx;
	296
a5a678c8	297	err = save_fpx_registers(pid, (unsigned long *) &fpx);
a5f6096c JD	298	if (err < 0){
	299	printk(KERN_ERR "copy_sc_to_user - save_fpx_registers "
	300	"failed, errno = %d\n", err);
	301	return 1;
	302	}
	303
b6024b21	304	err = convert_fxsr_to_user(&to_fp->fpstate, &fpx);
a5f6096c JD	305	if (err)
	306	return 1;
	307
b6024b21 EC	308	err \|= __put_user(fpx.swd, &to_fp->fpstate.status);
b6024b21 EC	309	err \|= __put_user(X86_FXSR_MAGIC, &to_fp->fpstate.magic);
a5f6096c JD	310	if (err)
	311	return 1;
	312
b6024b21	313	if (copy_to_user(&to_fp->fpstate._fxsr_env[0], &fpx,
a5f6096c JD	314	sizeof(struct user_fxsr_struct)))
a5f6096c JD	315	return 1;
f67aa2ff AV	316	} else
	317	#endif
	318	{
b6024b21	319	if (copy_to_user(to_fp, regs->regs.fp, sizeof(struct _xstate)))
a5f6096c JD	320	return 1;
a5f6096c JD	321	}
1da177e4	322
f67aa2ff	323	return 0;
1da177e4	324	}
1da177e4	325
f67aa2ff	326	#ifdef CONFIG_X86_32
ba180fd4	327	static int copy_ucontext_to_user(struct ucontext __user *uc,
b6024b21	328	struct _xstate __user fp, sigset_t set,
ba180fd4	329	unsigned long sp)
1da177e4 LT	330	{
	331	int err = 0;
	332
c40702c4	333	err \|= __save_altstack(&uc->uc_stack, sp);
f67aa2ff	334	err \|= copy_sc_to_user(&uc->uc_mcontext, fp, &current->thread.regs, 0);
1da177e4	335	err \|= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
5d86456d	336	return err;
1da177e4 LT	337	}
	338
	339	struct sigframe
	340	{
4d338e1a	341	char __user *pretcode;
1da177e4 LT	342	int sig;
1da177e4 LT	343	struct sigcontext sc;
b6024b21	344	struct _xstate fpstate;
1da177e4 LT	345	unsigned long extramask[_NSIG_WORDS-1];
	346	char retcode[8];
	347	};
	348
	349	struct rt_sigframe
	350	{
4d338e1a	351	char __user *pretcode;
1da177e4	352	int sig;
4d338e1a AV	353	struct siginfo __user *pinfo;
4d338e1a AV	354	void __user *puc;
1da177e4 LT	355	struct siginfo info;
1da177e4 LT	356	struct ucontext uc;
b6024b21	357	struct _xstate fpstate;
1da177e4 LT	358	char retcode[8];
	359	};
	360
307627ee RW	361	int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig,
307627ee RW	362	struct pt_regs regs, sigset_t mask)
1da177e4 LT	363	{
1da177e4 LT	364	struct sigframe __user *frame;
4d338e1a	365	void __user *restorer;
307627ee	366	int err = 0, sig = ksig->sig;
1da177e4	367
3896625d JD	368	/* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
3896625d JD	369	stack_top = ((stack_top + 4) & -16UL) - 4;
4d338e1a	370	frame = (struct sigframe __user *) stack_top - 1;
96d4f267	371	if (!access_ok(frame, sizeof(*frame)))
1da177e4 LT	372	return 1;
1da177e4 LT	373
4d338e1a	374	restorer = frame->retcode;
307627ee RW	375	if (ksig->ka.sa.sa_flags & SA_RESTORER)
307627ee RW	376	restorer = ksig->ka.sa.sa_restorer;
1da177e4 LT	377
	378	err \|= __put_user(restorer, &frame->pretcode);
	379	err \|= __put_user(sig, &frame->sig);
f67aa2ff	380	err \|= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
1da177e4 LT	381	if (_NSIG_WORDS > 1)
	382	err \|= __copy_to_user(&frame->extramask, &mask->sig[1],
	383	sizeof(frame->extramask));
	384
	385	/*
	386	* This is popl %eax ; movl $,%eax ; int $0x80
	387	*
	388	* WE DO NOT USE IT ANY MORE! It's only left here for historical
	389	* reasons and because gdb uses it as a signature to notice
	390	* signal handler stack frames.
	391	*/
	392	err \|= __put_user(0xb858, (short __user *)(frame->retcode+0));
	393	err \|= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
	394	err \|= __put_user(0x80cd, (short __user *)(frame->retcode+6));
	395
ba180fd4	396	if (err)
fbe98686	397	return err;
1da177e4 LT	398
1da177e4 LT	399	PT_REGS_SP(regs) = (unsigned long) frame;
307627ee	400	PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
243412be AV	401	PT_REGS_AX(regs) = (unsigned long) sig;
	402	PT_REGS_DX(regs) = (unsigned long) 0;
	403	PT_REGS_CX(regs) = (unsigned long) 0;
98c18238	404	return 0;
1da177e4 LT	405	}
1da177e4 LT	406
307627ee RW	407	int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
307627ee RW	408	struct pt_regs regs, sigset_t mask)
1da177e4 LT	409	{
1da177e4 LT	410	struct rt_sigframe __user *frame;
4d338e1a	411	void __user *restorer;
307627ee	412	int err = 0, sig = ksig->sig;
1da177e4 LT	413
1da177e4 LT	414	stack_top &= -8UL;
4d338e1a	415	frame = (struct rt_sigframe __user *) stack_top - 1;
96d4f267	416	if (!access_ok(frame, sizeof(*frame)))
1da177e4 LT	417	return 1;
1da177e4 LT	418
4d338e1a	419	restorer = frame->retcode;
307627ee RW	420	if (ksig->ka.sa.sa_flags & SA_RESTORER)
307627ee RW	421	restorer = ksig->ka.sa.sa_restorer;
1da177e4 LT	422
	423	err \|= __put_user(restorer, &frame->pretcode);
	424	err \|= __put_user(sig, &frame->sig);
	425	err \|= __put_user(&frame->info, &frame->pinfo);
	426	err \|= __put_user(&frame->uc, &frame->puc);
307627ee	427	err \|= copy_siginfo_to_user(&frame->info, &ksig->info);
1da177e4	428	err \|= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
fbe98686	429	PT_REGS_SP(regs));
1da177e4 LT	430
	431	/*
	432	* This is movl $,%eax ; int $0x80
	433	*
	434	* WE DO NOT USE IT ANY MORE! It's only left here for historical
	435	* reasons and because gdb uses it as a signature to notice
	436	* signal handler stack frames.
	437	*/
	438	err \|= __put_user(0xb8, (char __user *)(frame->retcode+0));
	439	err \|= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
	440	err \|= __put_user(0x80cd, (short __user *)(frame->retcode+5));
	441
ba180fd4	442	if (err)
fbe98686	443	return err;
1da177e4	444
fbe98686	445	PT_REGS_SP(regs) = (unsigned long) frame;
307627ee	446	PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
243412be AV	447	PT_REGS_AX(regs) = (unsigned long) sig;
	448	PT_REGS_DX(regs) = (unsigned long) &frame->info;
	449	PT_REGS_CX(regs) = (unsigned long) &frame->uc;
98c18238	450	return 0;
1da177e4 LT	451	}
1da177e4 LT	452
3fe26fa3	453	long sys_sigreturn(void)
1da177e4 LT	454	{
1da177e4 LT	455	unsigned long sp = PT_REGS_SP(&current->thread.regs);
4d338e1a	456	struct sigframe __user frame = (struct sigframe __user )(sp - 8);
1da177e4 LT	457	sigset_t set;
1da177e4 LT	458	struct sigcontext __user *sc = &frame->sc;
1da177e4 LT	459	int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
1da177e4 LT	460
de379379	461	if (copy_from_user(&set.sig[0], &sc->oldmask, sizeof(set.sig[0])) \|\|
8090bfd2	462	copy_from_user(&set.sig[1], frame->extramask, sig_size))
1da177e4 LT	463	goto segfault;
1da177e4 LT	464
78722a44	465	set_current_blocked(&set);
1da177e4	466
ba180fd4	467	if (copy_sc_from_user(&current->thread.regs, sc))
1da177e4 LT	468	goto segfault;
	469
	470	/* Avoid ERESTART handling */
	471	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
5d86456d	472	return PT_REGS_SYSCALL_RET(&current->thread.regs);
1da177e4 LT	473
1da177e4 LT	474	segfault:
3cf5d076	475	force_sig(SIGSEGV);
1da177e4 LT	476	return 0;
	477	}
	478
f67aa2ff AV	479	#else
	480
	481	struct rt_sigframe
	482	{
	483	char __user *pretcode;
	484	struct ucontext uc;
	485	struct siginfo info;
b6024b21	486	struct _xstate fpstate;
f67aa2ff AV	487	};
f67aa2ff AV	488
307627ee RW	489	int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
307627ee RW	490	struct pt_regs regs, sigset_t set)
f67aa2ff AV	491	{
f67aa2ff AV	492	struct rt_sigframe __user *frame;
307627ee	493	int err = 0, sig = ksig->sig;
8090bfd2	494	unsigned long fp_to;
f67aa2ff AV	495
	496	frame = (struct rt_sigframe __user *)
	497	round_down(stack_top - sizeof(struct rt_sigframe), 16);
	498	/* Subtract 128 for a red zone and 8 for proper alignment */
	499	frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
	500
96d4f267	501	if (!access_ok(frame, sizeof(*frame)))
f67aa2ff AV	502	goto out;
f67aa2ff AV	503
307627ee RW	504	if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
307627ee RW	505	err \|= copy_siginfo_to_user(&frame->info, &ksig->info);
f67aa2ff AV	506	if (err)
	507	goto out;
	508	}
	509
	510	/* Create the ucontext. */
	511	err \|= __put_user(0, &frame->uc.uc_flags);
	512	err \|= __put_user(0, &frame->uc.uc_link);
c40702c4	513	err \|= __save_altstack(&frame->uc.uc_stack, PT_REGS_SP(regs));
f67aa2ff AV	514	err \|= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
f67aa2ff AV	515	set->sig[0]);
8090bfd2 RW	516
	517	fp_to = (unsigned long)&frame->fpstate;
	518
	519	err \|= __put_user(fp_to, &frame->uc.uc_mcontext.fpstate);
f67aa2ff	520	if (sizeof(*set) == 16) {
ffc51be8 AV	521	err \|= __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
ffc51be8 AV	522	err \|= __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
f67aa2ff AV	523	}
	524	else
	525	err \|= __copy_to_user(&frame->uc.uc_sigmask, set,
	526	sizeof(*set));
	527
	528	/*
	529	* Set up to return from userspace. If provided, use a stub
	530	* already in userspace.
	531	*/
	532	/* x86-64 should always use SA_RESTORER. */
307627ee	533	if (ksig->ka.sa.sa_flags & SA_RESTORER)
6c684465 RW	534	err \|= __put_user((void *)ksig->ka.sa.sa_restorer,
6c684465 RW	535	&frame->pretcode);
f67aa2ff AV	536	else
	537	/* could use a vstub here */
	538	return err;
	539
	540	if (err)
	541	return err;
	542
f67aa2ff	543	PT_REGS_SP(regs) = (unsigned long) frame;
243412be	544	PT_REGS_DI(regs) = sig;
f67aa2ff	545	/* In case the signal handler was declared without prototypes */
243412be	546	PT_REGS_AX(regs) = 0;
f67aa2ff AV	547
	548	/*
	549	* This also works for non SA_SIGINFO handlers because they expect the
	550	* next argument after the signal number on the stack.
	551	*/
243412be AV	552	PT_REGS_SI(regs) = (unsigned long) &frame->info;
243412be AV	553	PT_REGS_DX(regs) = (unsigned long) &frame->uc;
307627ee	554	PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
f67aa2ff AV	555	out:
	556	return err;
	557	}
	558	#endif
	559
3fe26fa3	560	long sys_rt_sigreturn(void)
1da177e4	561	{
4d338e1a	562	unsigned long sp = PT_REGS_SP(&current->thread.regs);
ba180fd4	563	struct rt_sigframe __user *frame =
f67aa2ff	564	(struct rt_sigframe __user *)(sp - sizeof(long));
1da177e4	565	struct ucontext __user *uc = &frame->uc;
f67aa2ff	566	sigset_t set;
1da177e4	567
f67aa2ff	568	if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
1da177e4 LT	569	goto segfault;
1da177e4 LT	570
78722a44	571	set_current_blocked(&set);
1da177e4	572
ba180fd4	573	if (copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
1da177e4 LT	574	goto segfault;
	575
	576	/* Avoid ERESTART handling */
	577	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
5d86456d	578	return PT_REGS_SYSCALL_RET(&current->thread.regs);
1da177e4 LT	579
1da177e4 LT	580	segfault:
3cf5d076	581	force_sig(SIGSEGV);
1da177e4 LT	582	return 0;
1da177e4 LT	583	}