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