835c34a168
Since the x86 merge, lots of files that referenced their own filenames are no longer correct. Rather than keep them up to date, just delete them, as they add no real value. Additionally: - fix up comment formatting in scx200_32.c - Remove a credit from myself in setup_64.c from a time when we had no SCM - remove longwinded history from tsc_32.c which can be figured out from git. Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
544 lines
13 KiB
C
544 lines
13 KiB
C
/*
|
|
* Copyright (C) 1994 Linus Torvalds
|
|
*
|
|
* Pentium III FXSR, SSE support
|
|
* General FPU state handling cleanups
|
|
* Gareth Hughes <gareth@valinux.com>, May 2000
|
|
*/
|
|
|
|
#include <linux/sched.h>
|
|
#include <linux/module.h>
|
|
#include <asm/processor.h>
|
|
#include <asm/i387.h>
|
|
#include <asm/math_emu.h>
|
|
#include <asm/sigcontext.h>
|
|
#include <asm/user.h>
|
|
#include <asm/ptrace.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
#ifdef CONFIG_MATH_EMULATION
|
|
#define HAVE_HWFP (boot_cpu_data.hard_math)
|
|
#else
|
|
#define HAVE_HWFP 1
|
|
#endif
|
|
|
|
static unsigned long mxcsr_feature_mask __read_mostly = 0xffffffff;
|
|
|
|
void mxcsr_feature_mask_init(void)
|
|
{
|
|
unsigned long mask = 0;
|
|
clts();
|
|
if (cpu_has_fxsr) {
|
|
memset(¤t->thread.i387.fxsave, 0, sizeof(struct i387_fxsave_struct));
|
|
asm volatile("fxsave %0" : : "m" (current->thread.i387.fxsave));
|
|
mask = current->thread.i387.fxsave.mxcsr_mask;
|
|
if (mask == 0) mask = 0x0000ffbf;
|
|
}
|
|
mxcsr_feature_mask &= mask;
|
|
stts();
|
|
}
|
|
|
|
/*
|
|
* The _current_ task is using the FPU for the first time
|
|
* so initialize it and set the mxcsr to its default
|
|
* value at reset if we support XMM instructions and then
|
|
* remeber the current task has used the FPU.
|
|
*/
|
|
void init_fpu(struct task_struct *tsk)
|
|
{
|
|
if (cpu_has_fxsr) {
|
|
memset(&tsk->thread.i387.fxsave, 0, sizeof(struct i387_fxsave_struct));
|
|
tsk->thread.i387.fxsave.cwd = 0x37f;
|
|
if (cpu_has_xmm)
|
|
tsk->thread.i387.fxsave.mxcsr = 0x1f80;
|
|
} else {
|
|
memset(&tsk->thread.i387.fsave, 0, sizeof(struct i387_fsave_struct));
|
|
tsk->thread.i387.fsave.cwd = 0xffff037fu;
|
|
tsk->thread.i387.fsave.swd = 0xffff0000u;
|
|
tsk->thread.i387.fsave.twd = 0xffffffffu;
|
|
tsk->thread.i387.fsave.fos = 0xffff0000u;
|
|
}
|
|
/* only the device not available exception or ptrace can call init_fpu */
|
|
set_stopped_child_used_math(tsk);
|
|
}
|
|
|
|
/*
|
|
* FPU lazy state save handling.
|
|
*/
|
|
|
|
void kernel_fpu_begin(void)
|
|
{
|
|
struct thread_info *thread = current_thread_info();
|
|
|
|
preempt_disable();
|
|
if (thread->status & TS_USEDFPU) {
|
|
__save_init_fpu(thread->task);
|
|
return;
|
|
}
|
|
clts();
|
|
}
|
|
EXPORT_SYMBOL_GPL(kernel_fpu_begin);
|
|
|
|
/*
|
|
* 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 tos = (fxsave->swd >> 11) & 7;
|
|
unsigned long twd = (unsigned long) fxsave->twd;
|
|
unsigned long tag;
|
|
unsigned long ret = 0xffff0000u;
|
|
int i;
|
|
|
|
#define FPREG_ADDR(f, n) ((void *)&(f)->st_space + (n) * 16);
|
|
|
|
for ( i = 0 ; i < 8 ; i++ ) {
|
|
if ( twd & 0x1 ) {
|
|
st = FPREG_ADDR( fxsave, (i - tos) & 7 );
|
|
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* FPU state interaction.
|
|
*/
|
|
|
|
unsigned short get_fpu_cwd( struct task_struct *tsk )
|
|
{
|
|
if ( cpu_has_fxsr ) {
|
|
return tsk->thread.i387.fxsave.cwd;
|
|
} else {
|
|
return (unsigned short)tsk->thread.i387.fsave.cwd;
|
|
}
|
|
}
|
|
|
|
unsigned short get_fpu_swd( struct task_struct *tsk )
|
|
{
|
|
if ( cpu_has_fxsr ) {
|
|
return tsk->thread.i387.fxsave.swd;
|
|
} else {
|
|
return (unsigned short)tsk->thread.i387.fsave.swd;
|
|
}
|
|
}
|
|
|
|
#if 0
|
|
unsigned short get_fpu_twd( struct task_struct *tsk )
|
|
{
|
|
if ( cpu_has_fxsr ) {
|
|
return tsk->thread.i387.fxsave.twd;
|
|
} else {
|
|
return (unsigned short)tsk->thread.i387.fsave.twd;
|
|
}
|
|
}
|
|
#endif /* 0 */
|
|
|
|
unsigned short get_fpu_mxcsr( struct task_struct *tsk )
|
|
{
|
|
if ( cpu_has_xmm ) {
|
|
return tsk->thread.i387.fxsave.mxcsr;
|
|
} else {
|
|
return 0x1f80;
|
|
}
|
|
}
|
|
|
|
#if 0
|
|
|
|
void set_fpu_cwd( struct task_struct *tsk, unsigned short cwd )
|
|
{
|
|
if ( cpu_has_fxsr ) {
|
|
tsk->thread.i387.fxsave.cwd = cwd;
|
|
} else {
|
|
tsk->thread.i387.fsave.cwd = ((long)cwd | 0xffff0000u);
|
|
}
|
|
}
|
|
|
|
void set_fpu_swd( struct task_struct *tsk, unsigned short swd )
|
|
{
|
|
if ( cpu_has_fxsr ) {
|
|
tsk->thread.i387.fxsave.swd = swd;
|
|
} else {
|
|
tsk->thread.i387.fsave.swd = ((long)swd | 0xffff0000u);
|
|
}
|
|
}
|
|
|
|
void set_fpu_twd( struct task_struct *tsk, unsigned short twd )
|
|
{
|
|
if ( cpu_has_fxsr ) {
|
|
tsk->thread.i387.fxsave.twd = twd_i387_to_fxsr(twd);
|
|
} else {
|
|
tsk->thread.i387.fsave.twd = ((long)twd | 0xffff0000u);
|
|
}
|
|
}
|
|
|
|
#endif /* 0 */
|
|
|
|
/*
|
|
* FXSR floating point environment conversions.
|
|
*/
|
|
|
|
static int convert_fxsr_to_user( struct _fpstate __user *buf,
|
|
struct i387_fxsave_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 i387_fxsave_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;
|
|
}
|
|
|
|
/*
|
|
* Signal frame handlers.
|
|
*/
|
|
|
|
static inline int save_i387_fsave( struct _fpstate __user *buf )
|
|
{
|
|
struct task_struct *tsk = current;
|
|
|
|
unlazy_fpu( tsk );
|
|
tsk->thread.i387.fsave.status = tsk->thread.i387.fsave.swd;
|
|
if ( __copy_to_user( buf, &tsk->thread.i387.fsave,
|
|
sizeof(struct i387_fsave_struct) ) )
|
|
return -1;
|
|
return 1;
|
|
}
|
|
|
|
static int save_i387_fxsave( struct _fpstate __user *buf )
|
|
{
|
|
struct task_struct *tsk = current;
|
|
int err = 0;
|
|
|
|
unlazy_fpu( tsk );
|
|
|
|
if ( convert_fxsr_to_user( buf, &tsk->thread.i387.fxsave ) )
|
|
return -1;
|
|
|
|
err |= __put_user( tsk->thread.i387.fxsave.swd, &buf->status );
|
|
err |= __put_user( X86_FXSR_MAGIC, &buf->magic );
|
|
if ( err )
|
|
return -1;
|
|
|
|
if ( __copy_to_user( &buf->_fxsr_env[0], &tsk->thread.i387.fxsave,
|
|
sizeof(struct i387_fxsave_struct) ) )
|
|
return -1;
|
|
return 1;
|
|
}
|
|
|
|
int save_i387( struct _fpstate __user *buf )
|
|
{
|
|
if ( !used_math() )
|
|
return 0;
|
|
|
|
/* This will cause a "finit" to be triggered by the next
|
|
* attempted FPU operation by the 'current' process.
|
|
*/
|
|
clear_used_math();
|
|
|
|
if ( HAVE_HWFP ) {
|
|
if ( cpu_has_fxsr ) {
|
|
return save_i387_fxsave( buf );
|
|
} else {
|
|
return save_i387_fsave( buf );
|
|
}
|
|
} else {
|
|
return save_i387_soft( ¤t->thread.i387.soft, buf );
|
|
}
|
|
}
|
|
|
|
static inline int restore_i387_fsave( struct _fpstate __user *buf )
|
|
{
|
|
struct task_struct *tsk = current;
|
|
clear_fpu( tsk );
|
|
return __copy_from_user( &tsk->thread.i387.fsave, buf,
|
|
sizeof(struct i387_fsave_struct) );
|
|
}
|
|
|
|
static int restore_i387_fxsave( struct _fpstate __user *buf )
|
|
{
|
|
int err;
|
|
struct task_struct *tsk = current;
|
|
clear_fpu( tsk );
|
|
err = __copy_from_user( &tsk->thread.i387.fxsave, &buf->_fxsr_env[0],
|
|
sizeof(struct i387_fxsave_struct) );
|
|
/* mxcsr reserved bits must be masked to zero for security reasons */
|
|
tsk->thread.i387.fxsave.mxcsr &= mxcsr_feature_mask;
|
|
return err ? 1 : convert_fxsr_from_user( &tsk->thread.i387.fxsave, buf );
|
|
}
|
|
|
|
int restore_i387( struct _fpstate __user *buf )
|
|
{
|
|
int err;
|
|
|
|
if ( HAVE_HWFP ) {
|
|
if ( cpu_has_fxsr ) {
|
|
err = restore_i387_fxsave( buf );
|
|
} else {
|
|
err = restore_i387_fsave( buf );
|
|
}
|
|
} else {
|
|
err = restore_i387_soft( ¤t->thread.i387.soft, buf );
|
|
}
|
|
set_used_math();
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ptrace request handlers.
|
|
*/
|
|
|
|
static inline int get_fpregs_fsave( struct user_i387_struct __user *buf,
|
|
struct task_struct *tsk )
|
|
{
|
|
return __copy_to_user( buf, &tsk->thread.i387.fsave,
|
|
sizeof(struct user_i387_struct) );
|
|
}
|
|
|
|
static inline int get_fpregs_fxsave( struct user_i387_struct __user *buf,
|
|
struct task_struct *tsk )
|
|
{
|
|
return convert_fxsr_to_user( (struct _fpstate __user *)buf,
|
|
&tsk->thread.i387.fxsave );
|
|
}
|
|
|
|
int get_fpregs( struct user_i387_struct __user *buf, struct task_struct *tsk )
|
|
{
|
|
if ( HAVE_HWFP ) {
|
|
if ( cpu_has_fxsr ) {
|
|
return get_fpregs_fxsave( buf, tsk );
|
|
} else {
|
|
return get_fpregs_fsave( buf, tsk );
|
|
}
|
|
} else {
|
|
return save_i387_soft( &tsk->thread.i387.soft,
|
|
(struct _fpstate __user *)buf );
|
|
}
|
|
}
|
|
|
|
static inline int set_fpregs_fsave( struct task_struct *tsk,
|
|
struct user_i387_struct __user *buf )
|
|
{
|
|
return __copy_from_user( &tsk->thread.i387.fsave, buf,
|
|
sizeof(struct user_i387_struct) );
|
|
}
|
|
|
|
static inline int set_fpregs_fxsave( struct task_struct *tsk,
|
|
struct user_i387_struct __user *buf )
|
|
{
|
|
return convert_fxsr_from_user( &tsk->thread.i387.fxsave,
|
|
(struct _fpstate __user *)buf );
|
|
}
|
|
|
|
int set_fpregs( struct task_struct *tsk, struct user_i387_struct __user *buf )
|
|
{
|
|
if ( HAVE_HWFP ) {
|
|
if ( cpu_has_fxsr ) {
|
|
return set_fpregs_fxsave( tsk, buf );
|
|
} else {
|
|
return set_fpregs_fsave( tsk, buf );
|
|
}
|
|
} else {
|
|
return restore_i387_soft( &tsk->thread.i387.soft,
|
|
(struct _fpstate __user *)buf );
|
|
}
|
|
}
|
|
|
|
int get_fpxregs( struct user_fxsr_struct __user *buf, struct task_struct *tsk )
|
|
{
|
|
if ( cpu_has_fxsr ) {
|
|
if (__copy_to_user( buf, &tsk->thread.i387.fxsave,
|
|
sizeof(struct user_fxsr_struct) ))
|
|
return -EFAULT;
|
|
return 0;
|
|
} else {
|
|
return -EIO;
|
|
}
|
|
}
|
|
|
|
int set_fpxregs( struct task_struct *tsk, struct user_fxsr_struct __user *buf )
|
|
{
|
|
int ret = 0;
|
|
|
|
if ( cpu_has_fxsr ) {
|
|
if (__copy_from_user( &tsk->thread.i387.fxsave, buf,
|
|
sizeof(struct user_fxsr_struct) ))
|
|
ret = -EFAULT;
|
|
/* mxcsr reserved bits must be masked to zero for security reasons */
|
|
tsk->thread.i387.fxsave.mxcsr &= mxcsr_feature_mask;
|
|
} else {
|
|
ret = -EIO;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* FPU state for core dumps.
|
|
*/
|
|
|
|
static inline void copy_fpu_fsave( struct task_struct *tsk,
|
|
struct user_i387_struct *fpu )
|
|
{
|
|
memcpy( fpu, &tsk->thread.i387.fsave,
|
|
sizeof(struct user_i387_struct) );
|
|
}
|
|
|
|
static inline void copy_fpu_fxsave( struct task_struct *tsk,
|
|
struct user_i387_struct *fpu )
|
|
{
|
|
unsigned short *to;
|
|
unsigned short *from;
|
|
int i;
|
|
|
|
memcpy( fpu, &tsk->thread.i387.fxsave, 7 * sizeof(long) );
|
|
|
|
to = (unsigned short *)&fpu->st_space[0];
|
|
from = (unsigned short *)&tsk->thread.i387.fxsave.st_space[0];
|
|
for ( i = 0 ; i < 8 ; i++, to += 5, from += 8 ) {
|
|
memcpy( to, from, 5 * sizeof(unsigned short) );
|
|
}
|
|
}
|
|
|
|
int dump_fpu( struct pt_regs *regs, struct user_i387_struct *fpu )
|
|
{
|
|
int fpvalid;
|
|
struct task_struct *tsk = current;
|
|
|
|
fpvalid = !!used_math();
|
|
if ( fpvalid ) {
|
|
unlazy_fpu( tsk );
|
|
if ( cpu_has_fxsr ) {
|
|
copy_fpu_fxsave( tsk, fpu );
|
|
} else {
|
|
copy_fpu_fsave( tsk, fpu );
|
|
}
|
|
}
|
|
|
|
return fpvalid;
|
|
}
|
|
EXPORT_SYMBOL(dump_fpu);
|
|
|
|
int dump_task_fpu(struct task_struct *tsk, struct user_i387_struct *fpu)
|
|
{
|
|
int fpvalid = !!tsk_used_math(tsk);
|
|
|
|
if (fpvalid) {
|
|
if (tsk == current)
|
|
unlazy_fpu(tsk);
|
|
if (cpu_has_fxsr)
|
|
copy_fpu_fxsave(tsk, fpu);
|
|
else
|
|
copy_fpu_fsave(tsk, fpu);
|
|
}
|
|
return fpvalid;
|
|
}
|
|
|
|
int dump_task_extended_fpu(struct task_struct *tsk, struct user_fxsr_struct *fpu)
|
|
{
|
|
int fpvalid = tsk_used_math(tsk) && cpu_has_fxsr;
|
|
|
|
if (fpvalid) {
|
|
if (tsk == current)
|
|
unlazy_fpu(tsk);
|
|
memcpy(fpu, &tsk->thread.i387.fxsave, sizeof(*fpu));
|
|
}
|
|
return fpvalid;
|
|
}
|