[PATCH] autofs4: header file update

[pandora-kernel.git] / include / asm-i386 / i387.h

diff --git a/include/asm-i386/i387.h b/include/asm-i386/i387.h
index 152d0ba..434936c 100644 (file)
--- a/include/asm-i386/i387.h
+++ b/include/asm-i386/i387.h
@@ -13,6 +13,7 @@
 
 #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>
@@ -38,23 +39,46 @@ extern void init_fpu(struct task_struct *);
 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 %1 ; fwait ;" GENERIC_NOP2,
-               "fxsave %1 ; fnclex",
+               "fnsave %[fx] ;fwait;" GENERIC_NOP8 GENERIC_NOP4,
+               "fxsave %[fx]\n"
+               "bt $7,%[fsw] ; jnc 1f ; fnclex\n1:",
                X86_FEATURE_FXSR,
-               "m" (tsk->thread.i387.fxsave)
-               :"memory");
+               [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 ); \
+               save_init_fpu( tsk );                   \
+       else                                            \
+               tsk->fpu_counter = 0;                   \
 } while (0)
 
 #define __clear_fpu( tsk )                                     \
@@ -96,6 +120,7 @@ static inline void save_init_fpu( struct task_struct *tsk )
 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...