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-rw-r--r--include/asm-x86/i387_32.h151
1 files changed, 151 insertions, 0 deletions
diff --git a/include/asm-x86/i387_32.h b/include/asm-x86/i387_32.h
new file mode 100644
index 00000000000..cdd1e248e3b
--- /dev/null
+++ b/include/asm-x86/i387_32.h
@@ -0,0 +1,151 @@
+/*
+ * include/asm-i386/i387.h
+ *
+ * Copyright (C) 1994 Linus Torvalds
+ *
+ * Pentium III FXSR, SSE support
+ * General FPU state handling cleanups
+ * Gareth Hughes <gareth@valinux.com>, May 2000
+ */
+
+#ifndef __ASM_I386_I387_H
+#define __ASM_I386_I387_H
+
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/kernel_stat.h>
+#include <asm/processor.h>
+#include <asm/sigcontext.h>
+#include <asm/user.h>
+
+extern void mxcsr_feature_mask_init(void);
+extern void init_fpu(struct task_struct *);
+
+/*
+ * FPU lazy state save handling...
+ */
+
+/*
+ * The "nop" is needed to make the instructions the same
+ * length.
+ */
+#define restore_fpu(tsk) \
+ alternative_input( \
+ "nop ; frstor %1", \
+ "fxrstor %1", \
+ X86_FEATURE_FXSR, \
+ "m" ((tsk)->thread.i387.fxsave))
+
+extern void kernel_fpu_begin(void);
+#define kernel_fpu_end() do { stts(); preempt_enable(); } while(0)
+
+/* We need a safe address that is cheap to find and that is already
+ in L1 during context switch. The best choices are unfortunately
+ different for UP and SMP */
+#ifdef CONFIG_SMP
+#define safe_address (__per_cpu_offset[0])
+#else
+#define safe_address (kstat_cpu(0).cpustat.user)
+#endif
+
+/*
+ * These must be called with preempt disabled
+ */
+static inline void __save_init_fpu( struct task_struct *tsk )
+{
+ /* Use more nops than strictly needed in case the compiler
+ varies code */
+ alternative_input(
+ "fnsave %[fx] ;fwait;" GENERIC_NOP8 GENERIC_NOP4,
+ "fxsave %[fx]\n"
+ "bt $7,%[fsw] ; jnc 1f ; fnclex\n1:",
+ X86_FEATURE_FXSR,
+ [fx] "m" (tsk->thread.i387.fxsave),
+ [fsw] "m" (tsk->thread.i387.fxsave.swd) : "memory");
+ /* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception
+ is pending. Clear the x87 state here by setting it to fixed
+ values. safe_address is a random variable that should be in L1 */
+ alternative_input(
+ GENERIC_NOP8 GENERIC_NOP2,
+ "emms\n\t" /* clear stack tags */
+ "fildl %[addr]", /* set F?P to defined value */
+ X86_FEATURE_FXSAVE_LEAK,
+ [addr] "m" (safe_address));
+ task_thread_info(tsk)->status &= ~TS_USEDFPU;
+}
+
+#define __unlazy_fpu( tsk ) do { \
+ if (task_thread_info(tsk)->status & TS_USEDFPU) { \
+ __save_init_fpu(tsk); \
+ stts(); \
+ } else \
+ tsk->fpu_counter = 0; \
+} while (0)
+
+#define __clear_fpu( tsk ) \
+do { \
+ if (task_thread_info(tsk)->status & TS_USEDFPU) { \
+ asm volatile("fnclex ; fwait"); \
+ task_thread_info(tsk)->status &= ~TS_USEDFPU; \
+ stts(); \
+ } \
+} while (0)
+
+
+/*
+ * These disable preemption on their own and are safe
+ */
+static inline void save_init_fpu( struct task_struct *tsk )
+{
+ preempt_disable();
+ __save_init_fpu(tsk);
+ stts();
+ preempt_enable();
+}
+
+#define unlazy_fpu( tsk ) do { \
+ preempt_disable(); \
+ __unlazy_fpu(tsk); \
+ preempt_enable(); \
+} while (0)
+
+#define clear_fpu( tsk ) do { \
+ preempt_disable(); \
+ __clear_fpu( tsk ); \
+ preempt_enable(); \
+} while (0)
+
+/*
+ * FPU state interaction...
+ */
+extern unsigned short get_fpu_cwd( struct task_struct *tsk );
+extern unsigned short get_fpu_swd( struct task_struct *tsk );
+extern unsigned short get_fpu_mxcsr( struct task_struct *tsk );
+extern asmlinkage void math_state_restore(void);
+
+/*
+ * Signal frame handlers...
+ */
+extern int save_i387( struct _fpstate __user *buf );
+extern int restore_i387( struct _fpstate __user *buf );
+
+/*
+ * 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 );
+
+extern int get_fpxregs( struct user_fxsr_struct __user *buf,
+ struct task_struct *tsk );
+extern int set_fpxregs( struct task_struct *tsk,
+ struct user_fxsr_struct __user *buf );
+
+/*
+ * FPU state for core dumps...
+ */
+extern int dump_fpu( struct pt_regs *regs,
+ struct user_i387_struct *fpu );
+
+#endif /* __ASM_I386_I387_H */