/* * include/asm-x86_64/i387.h * * Copyright (C) 1994 Linus Torvalds * * Pentium III FXSR, SSE support * General FPU state handling cleanups * Gareth Hughes <gareth@valinux.com>, May 2000 * x86-64 work by Andi Kleen 2002 */ #ifndef __ASM_X86_64_I387_H #define __ASM_X86_64_I387_H #include <linux/sched.h> #include <asm/processor.h> #include <asm/sigcontext.h> #include <asm/user.h> #include <asm/thread_info.h> #include <asm/uaccess.h> extern void fpu_init(void); extern unsigned int mxcsr_feature_mask; extern void mxcsr_feature_mask_init(void); extern void init_fpu(struct task_struct *child); extern int save_i387(struct _fpstate __user *buf); /* * FPU lazy state save handling... */ #define unlazy_fpu(tsk) do { \ if ((tsk)->thread_info->status & TS_USEDFPU) \ save_init_fpu(tsk); \ } while (0) /* Ignore delayed exceptions from user space */ static inline void tolerant_fwait(void) { asm volatile("1: fwait\n" "2:\n" " .section __ex_table,\"a\"\n" " .align 8\n" " .quad 1b,2b\n" " .previous\n"); } #define clear_fpu(tsk) do { \ if ((tsk)->thread_info->status & TS_USEDFPU) { \ tolerant_fwait(); \ (tsk)->thread_info->status &= ~TS_USEDFPU; \ stts(); \ } \ } while (0) /* * ptrace request handers... */ extern int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *tsk); extern int set_fpregs(struct task_struct *tsk, struct user_i387_struct __user *buf); /* * i387 state interaction */ #define get_fpu_mxcsr(t) ((t)->thread.i387.fxsave.mxcsr) #define get_fpu_cwd(t) ((t)->thread.i387.fxsave.cwd) #define get_fpu_fxsr_twd(t) ((t)->thread.i387.fxsave.twd) #define get_fpu_swd(t) ((t)->thread.i387.fxsave.swd) #define set_fpu_cwd(t,val) ((t)->thread.i387.fxsave.cwd = (val)) #define set_fpu_swd(t,val) ((t)->thread.i387.fxsave.swd = (val)) #define set_fpu_fxsr_twd(t,val) ((t)->thread.i387.fxsave.twd = (val)) static inline int restore_fpu_checking(struct i387_fxsave_struct *fx) { int err; asm volatile("1: rex64 ; fxrstor (%[fx])\n\t" "2:\n" ".section .fixup,\"ax\"\n" "3: movl $-1,%[err]\n" " jmp 2b\n" ".previous\n" ".section __ex_table,\"a\"\n" " .align 8\n" " .quad 1b,3b\n" ".previous" : [err] "=r" (err) : [fx] "r" (fx), "0" (0)); if (unlikely(err)) init_fpu(current); return err; } static inline int save_i387_checking(struct i387_fxsave_struct __user *fx) { int err; asm volatile("1: rex64 ; fxsave (%[fx])\n\t" "2:\n" ".section .fixup,\"ax\"\n" "3: movl $-1,%[err]\n" " jmp 2b\n" ".previous\n" ".section __ex_table,\"a\"\n" " .align 8\n" " .quad 1b,3b\n" ".previous" : [err] "=r" (err) : [fx] "r" (fx), "0" (0)); if (unlikely(err)) __clear_user(fx, sizeof(struct i387_fxsave_struct)); return err; } static inline void kernel_fpu_begin(void) { struct thread_info *me = current_thread_info(); preempt_disable(); if (me->status & TS_USEDFPU) { asm volatile("rex64 ; fxsave %0 ; fnclex" : "=m" (me->task->thread.i387.fxsave)); me->status &= ~TS_USEDFPU; return; } clts(); } static inline void kernel_fpu_end(void) { stts(); preempt_enable(); } static inline void save_init_fpu( struct task_struct *tsk ) { asm volatile( "rex64 ; fxsave %0 ; fnclex" : "=m" (tsk->thread.i387.fxsave)); tsk->thread_info->status &= ~TS_USEDFPU; stts(); } /* * This restores directly out of user space. Exceptions are handled. */ static inline int restore_i387(struct _fpstate __user *buf) { return restore_fpu_checking((__force struct i387_fxsave_struct *)buf); } #endif /* __ASM_X86_64_I387_H */