2 * include/asm-x86_64/i387.h
4 * Copyright (C) 1994 Linus Torvalds
6 * Pentium III FXSR, SSE support
7 * General FPU state handling cleanups
8 * Gareth Hughes <gareth@valinux.com>, May 2000
9 * x86-64 work by Andi Kleen 2002
12 #ifndef __ASM_X86_64_I387_H
13 #define __ASM_X86_64_I387_H
15 #include <linux/sched.h>
16 #include <asm/processor.h>
17 #include <asm/sigcontext.h>
19 #include <asm/thread_info.h>
20 #include <asm/uaccess.h>
22 extern void fpu_init(void);
23 extern unsigned int mxcsr_feature_mask;
24 extern void mxcsr_feature_mask_init(void);
25 extern void init_fpu(struct task_struct *child);
26 extern int save_i387(struct _fpstate __user *buf);
28 static inline int need_signal_i387(struct task_struct *me)
33 if (me->thread_info->status & TS_USEDFPU)
39 * FPU lazy state save handling...
42 #define unlazy_fpu(tsk) do { \
43 if ((tsk)->thread_info->status & TS_USEDFPU) \
47 /* Ignore delayed exceptions from user space */
48 static inline void tolerant_fwait(void)
50 asm volatile("1: fwait\n"
52 " .section __ex_table,\"a\"\n"
58 #define clear_fpu(tsk) do { \
59 if ((tsk)->thread_info->status & TS_USEDFPU) { \
61 (tsk)->thread_info->status &= ~TS_USEDFPU; \
67 * ptrace request handers...
69 extern int get_fpregs(struct user_i387_struct __user *buf,
70 struct task_struct *tsk);
71 extern int set_fpregs(struct task_struct *tsk,
72 struct user_i387_struct __user *buf);
75 * i387 state interaction
77 #define get_fpu_mxcsr(t) ((t)->thread.i387.fxsave.mxcsr)
78 #define get_fpu_cwd(t) ((t)->thread.i387.fxsave.cwd)
79 #define get_fpu_fxsr_twd(t) ((t)->thread.i387.fxsave.twd)
80 #define get_fpu_swd(t) ((t)->thread.i387.fxsave.swd)
81 #define set_fpu_cwd(t,val) ((t)->thread.i387.fxsave.cwd = (val))
82 #define set_fpu_swd(t,val) ((t)->thread.i387.fxsave.swd = (val))
83 #define set_fpu_fxsr_twd(t,val) ((t)->thread.i387.fxsave.twd = (val))
85 static inline int restore_fpu_checking(struct i387_fxsave_struct *fx)
88 asm volatile("1: rex64 ; fxrstor (%[fx])\n\t"
90 ".section .fixup,\"ax\"\n"
91 "3: movl $-1,%[err]\n"
94 ".section __ex_table,\"a\"\n"
99 : [fx] "r" (fx), "0" (0));
105 static inline int save_i387_checking(struct i387_fxsave_struct __user *fx)
108 asm volatile("1: rex64 ; fxsave (%[fx])\n\t"
110 ".section .fixup,\"ax\"\n"
111 "3: movl $-1,%[err]\n"
114 ".section __ex_table,\"a\"\n"
119 : [fx] "r" (fx), "0" (0));
121 __clear_user(fx, sizeof(struct i387_fxsave_struct));
125 static inline void kernel_fpu_begin(void)
127 struct thread_info *me = current_thread_info();
129 if (me->status & TS_USEDFPU) {
130 asm volatile("rex64 ; fxsave %0 ; fnclex"
131 : "=m" (me->task->thread.i387.fxsave));
132 me->status &= ~TS_USEDFPU;
138 static inline void kernel_fpu_end(void)
144 static inline void save_init_fpu( struct task_struct *tsk )
146 asm volatile( "rex64 ; fxsave %0 ; fnclex"
147 : "=m" (tsk->thread.i387.fxsave));
148 tsk->thread_info->status &= ~TS_USEDFPU;
153 * This restores directly out of user space. Exceptions are handled.
155 static inline int restore_i387(struct _fpstate __user *buf)
157 return restore_fpu_checking((__force struct i387_fxsave_struct *)buf);
160 #endif /* __ASM_X86_64_I387_H */