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Diffstat (limited to 'arch/x86/include/asm/i387.h')
-rw-r--r-- | arch/x86/include/asm/i387.h | 108 |
1 files changed, 0 insertions, 108 deletions
diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h deleted file mode 100644 index 6eb6fcb83..000000000 --- a/arch/x86/include/asm/i387.h +++ /dev/null @@ -1,108 +0,0 @@ -/* - * 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_I387_H -#define _ASM_X86_I387_H - -#ifndef __ASSEMBLY__ - -#include <linux/sched.h> -#include <linux/hardirq.h> - -struct pt_regs; -struct user_i387_struct; - -extern int init_fpu(struct task_struct *child); -extern void fpu_finit(struct fpu *fpu); -extern int dump_fpu(struct pt_regs *, struct user_i387_struct *); -extern void math_state_restore(void); - -extern bool irq_fpu_usable(void); - -/* - * Careful: __kernel_fpu_begin/end() must be called with preempt disabled - * and they don't touch the preempt state on their own. - * If you enable preemption after __kernel_fpu_begin(), preempt notifier - * should call the __kernel_fpu_end() to prevent the kernel/user FPU - * state from getting corrupted. KVM for example uses this model. - * - * All other cases use kernel_fpu_begin/end() which disable preemption - * during kernel FPU usage. - */ -extern void __kernel_fpu_begin(void); -extern void __kernel_fpu_end(void); - -static inline void kernel_fpu_begin(void) -{ - preempt_disable(); - WARN_ON_ONCE(!irq_fpu_usable()); - __kernel_fpu_begin(); -} - -static inline void kernel_fpu_end(void) -{ - __kernel_fpu_end(); - preempt_enable(); -} - -/* Must be called with preempt disabled */ -extern void kernel_fpu_disable(void); -extern void kernel_fpu_enable(void); - -/* - * Some instructions like VIA's padlock instructions generate a spurious - * DNA fault but don't modify SSE registers. And these instructions - * get used from interrupt context as well. To prevent these kernel instructions - * in interrupt context interacting wrongly with other user/kernel fpu usage, we - * should use them only in the context of irq_ts_save/restore() - */ -static inline int irq_ts_save(void) -{ - /* - * If in process context and not atomic, we can take a spurious DNA fault. - * Otherwise, doing clts() in process context requires disabling preemption - * or some heavy lifting like kernel_fpu_begin() - */ - if (!in_atomic()) - return 0; - - if (read_cr0() & X86_CR0_TS) { - clts(); - return 1; - } - - return 0; -} - -static inline void irq_ts_restore(int TS_state) -{ - if (TS_state) - stts(); -} - -/* - * The question "does this thread have fpu access?" - * is slightly racy, since preemption could come in - * and revoke it immediately after the test. - * - * However, even in that very unlikely scenario, - * we can just assume we have FPU access - typically - * to save the FP state - we'll just take a #NM - * fault and get the FPU access back. - */ -static inline int user_has_fpu(void) -{ - return current->thread.fpu.has_fpu; -} - -extern void unlazy_fpu(struct task_struct *tsk); - -#endif /* __ASSEMBLY__ */ - -#endif /* _ASM_X86_I387_H */ |