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yaml
---
r: 88744
b: refs/heads/master
c: f668964
h: refs/heads/master
v: v3
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Ingo Molnar committed Apr 17, 2008
1 parent 9c8ed22 commit 669a941
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Showing 2 changed files with 47 additions and 43 deletions.
2 changes: 1 addition & 1 deletion [refs]
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Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: ca9cda2f7b53da619fabde4c0c1bd5f61039bd5b
refs/heads/master: f668964ea1485c64cc9ab0721679fe9cd90cc406
88 changes: 46 additions & 42 deletions trunk/arch/x86/kernel/i387.c
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Original file line number Diff line number Diff line change
Expand Up @@ -5,45 +5,41 @@
* General FPU state handling cleanups
* Gareth Hughes <gareth@valinux.com>, May 2000
*/

#include <linux/sched.h>
#include <linux/module.h>
#include <linux/regset.h>
#include <linux/sched.h>

#include <asm/sigcontext.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>
#include <asm/ptrace.h>
#include <asm/i387.h>
#include <asm/user.h>

#ifdef CONFIG_X86_64

#include <asm/sigcontext32.h>
#include <asm/user32.h>

# include <asm/sigcontext32.h>
# include <asm/user32.h>
#else

#define save_i387_ia32 save_i387
#define restore_i387_ia32 restore_i387

#define _fpstate_ia32 _fpstate
#define user_i387_ia32_struct user_i387_struct
#define user32_fxsr_struct user_fxsr_struct

# define save_i387_ia32 save_i387
# define restore_i387_ia32 restore_i387
# define _fpstate_ia32 _fpstate
# define user_i387_ia32_struct user_i387_struct
# define user32_fxsr_struct user_fxsr_struct
#endif

#ifdef CONFIG_MATH_EMULATION
#define HAVE_HWFP (boot_cpu_data.hard_math)
# define HAVE_HWFP (boot_cpu_data.hard_math)
#else
#define HAVE_HWFP 1
# define HAVE_HWFP 1
#endif

static unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu;
static unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu;

void mxcsr_feature_mask_init(void)
{
unsigned long mask = 0;

clts();
if (cpu_has_fxsr) {
memset(&current->thread.i387.fxsave, 0,
Expand All @@ -69,10 +65,11 @@ void __cpuinit fpu_init(void)

if (offsetof(struct task_struct, thread.i387.fxsave) & 15)
__bad_fxsave_alignment();

set_in_cr4(X86_CR4_OSFXSR);
set_in_cr4(X86_CR4_OSXMMEXCPT);

write_cr0(oldcr0 & ~((1UL<<3)|(1UL<<2))); /* clear TS and EM */
write_cr0(oldcr0 & ~(X86_CR0_TS|X86_CR0_EM)); /* clear TS and EM */

mxcsr_feature_mask_init();
/* clean state in init */
Expand Down Expand Up @@ -178,6 +175,7 @@ static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */

return tmp;
}

Expand Down Expand Up @@ -232,8 +230,8 @@ static inline u32 twd_fxsr_to_i387(struct i387_fxsave_struct *fxsave)
* FXSR floating point environment conversions.
*/

static void convert_from_fxsr(struct user_i387_ia32_struct *env,
struct task_struct *tsk)
static void
convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk)
{
struct i387_fxsave_struct *fxsave = &tsk->thread.i387.fxsave;
struct _fpreg *to = (struct _fpreg *) &env->st_space[0];
Expand All @@ -252,10 +250,11 @@ static void convert_from_fxsr(struct user_i387_ia32_struct *env,
* should be actually ds/cs at fpu exception time, but
* that information is not available in 64bit mode.
*/
asm("mov %%ds,%0" : "=r" (env->fos));
asm("mov %%cs,%0" : "=r" (env->fcs));
asm("mov %%ds, %[fos]" : [fos] "=r" (env->fos));
asm("mov %%cs, %[fcs]" : [fcs] "=r" (env->fcs));
} else {
struct pt_regs *regs = task_pt_regs(tsk);

env->fos = 0xffff0000 | tsk->thread.ds;
env->fcs = regs->cs;
}
Expand Down Expand Up @@ -309,16 +308,18 @@ int fpregs_get(struct task_struct *target, const struct user_regset *regset,

init_fpu(target);

if (!cpu_has_fxsr)
if (!cpu_has_fxsr) {
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&target->thread.i387.fsave, 0, -1);
}

if (kbuf && pos == 0 && count == sizeof(env)) {
convert_from_fxsr(kbuf, target);
return 0;
}

convert_from_fxsr(&env, target);

return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &env, 0, -1);
}

Expand All @@ -335,9 +336,10 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset,
init_fpu(target);
set_stopped_child_used_math(target);

if (!cpu_has_fxsr)
if (!cpu_has_fxsr) {
return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.i387.fsave, 0, -1);
}

if (pos > 0 || count < sizeof(env))
convert_from_fxsr(&env, target);
Expand Down Expand Up @@ -392,38 +394,39 @@ int save_i387_ia32(struct _fpstate_ia32 __user *buf)
{
if (!used_math())
return 0;

/* This will cause a "finit" to be triggered by the next
/*
* 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 {
if (!HAVE_HWFP) {
return fpregs_soft_get(current, NULL,
0, sizeof(struct user_i387_ia32_struct),
NULL, buf) ? -1 : 1;
}

if (cpu_has_fxsr)
return save_i387_fxsave(buf);
else
return save_i387_fsave(buf);
}

static inline int restore_i387_fsave(struct _fpstate_ia32 __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_ia32 __user *buf)
{
int err;
struct task_struct *tsk = current;
struct user_i387_ia32_struct env;
int err;

clear_fpu(tsk);
err = __copy_from_user(&tsk->thread.i387.fxsave, &buf->_fxsr_env[0],
sizeof(struct i387_fxsave_struct));
Expand All @@ -432,6 +435,7 @@ static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf)
if (err || __copy_from_user(&env, buf, sizeof(env)))
return 1;
convert_to_fxsr(tsk, &env);

return 0;
}

Expand All @@ -440,17 +444,17 @@ int restore_i387_ia32(struct _fpstate_ia32 __user *buf)
int err;

if (HAVE_HWFP) {
if (cpu_has_fxsr) {
if (cpu_has_fxsr)
err = restore_i387_fxsave(buf);
} else {
else
err = restore_i387_fsave(buf);
}
} else {
err = fpregs_soft_set(current, NULL,
0, sizeof(struct user_i387_ia32_struct),
NULL, buf) != 0;
}
set_used_math();

return err;
}

Expand All @@ -463,8 +467,8 @@ int restore_i387_ia32(struct _fpstate_ia32 __user *buf)
*/
int dump_fpu(struct pt_regs *regs, struct user_i387_struct *fpu)
{
int fpvalid;
struct task_struct *tsk = current;
int fpvalid;

fpvalid = !!used_math();
if (fpvalid)
Expand Down

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