X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fi386%2Fkernel%2Fi387.c;h=d75524758daf770811e029536f6730c8b5c0fa21;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=0d35516ca293596bf199a79ecb75577d7417ce5c;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git

diff --git a/arch/i386/kernel/i387.c b/arch/i386/kernel/i387.c
index 0d35516ca..d75524758 100644
--- a/arch/i386/kernel/i387.c
+++ b/arch/i386/kernel/i387.c
@@ -10,6 +10,7 @@
 
 #include <linux/config.h>
 #include <linux/sched.h>
+#include <linux/module.h>
 #include <asm/processor.h>
 #include <asm/i387.h>
 #include <asm/math_emu.h>
@@ -24,7 +25,7 @@
 #define HAVE_HWFP 1
 #endif
 
-unsigned long mxcsr_feature_mask = 0xffffffff;
+static unsigned long mxcsr_feature_mask = 0xffffffff;
 
 void mxcsr_feature_mask_init(void)
 {
@@ -60,7 +61,8 @@ void init_fpu(struct task_struct *tsk)
 		tsk->thread.i387.fsave.twd = 0xffffffffu;
 		tsk->thread.i387.fsave.fos = 0xffff0000u;
 	}
-	tsk->used_math = 1;
+	/* only the device not available exception or ptrace can call init_fpu */
+	set_stopped_child_used_math(tsk);
 }
 
 /*
@@ -78,17 +80,7 @@ void kernel_fpu_begin(void)
 	}
 	clts();
 }
-
-void restore_fpu( struct task_struct *tsk )
-{
-	if ( cpu_has_fxsr ) {
-		asm volatile( "fxrstor %0"
-			      : : "m" (tsk->thread.i387.fxsave) );
-	} else {
-		asm volatile( "frstor %0"
-			      : : "m" (tsk->thread.i387.fsave) );
-	}
-}
+EXPORT_SYMBOL_GPL(kernel_fpu_begin);
 
 /*
  * FPU tag word conversions.
@@ -111,16 +103,17 @@ static inline unsigned short twd_i387_to_fxsr( unsigned short twd )
 static inline unsigned long twd_fxsr_to_i387( struct i387_fxsave_struct *fxsave )
 {
 	struct _fpxreg *st = NULL;
+	unsigned long tos = (fxsave->swd >> 11) & 7;
 	unsigned long twd = (unsigned long) fxsave->twd;
 	unsigned long tag;
 	unsigned long ret = 0xffff0000u;
 	int i;
 
-#define FPREG_ADDR(f, n)	((char *)&(f)->st_space + (n) * 16);
+#define FPREG_ADDR(f, n)	((void *)&(f)->st_space + (n) * 16);
 
 	for ( i = 0 ; i < 8 ; i++ ) {
 		if ( twd & 0x1 ) {
-			st = (struct _fpxreg *) FPREG_ADDR( fxsave, i );
+			st = FPREG_ADDR( fxsave, (i - tos) & 7 );
 
 			switch ( st->exponent & 0x7fff ) {
 			case 0x7fff:
@@ -175,6 +168,7 @@ unsigned short get_fpu_swd( struct task_struct *tsk )
 	}
 }
 
+#if 0
 unsigned short get_fpu_twd( struct task_struct *tsk )
 {
 	if ( cpu_has_fxsr ) {
@@ -183,6 +177,7 @@ unsigned short get_fpu_twd( struct task_struct *tsk )
 		return (unsigned short)tsk->thread.i387.fsave.twd;
 	}
 }
+#endif  /*  0  */
 
 unsigned short get_fpu_mxcsr( struct task_struct *tsk )
 {
@@ -193,6 +188,8 @@ unsigned short get_fpu_mxcsr( struct task_struct *tsk )
 	}
 }
 
+#if 0
+
 void set_fpu_cwd( struct task_struct *tsk, unsigned short cwd )
 {
 	if ( cpu_has_fxsr ) {
@@ -220,6 +217,8 @@ void set_fpu_twd( struct task_struct *tsk, unsigned short twd )
 	}
 }
 
+#endif  /*  0  */
+
 /*
  * FXSR floating point environment conversions.
  */
@@ -246,7 +245,7 @@ static int convert_fxsr_to_user( struct _fpstate __user *buf,
 	to = &buf->_st[0];
 	from = (struct _fpxreg *) &fxsave->st_space[0];
 	for ( i = 0 ; i < 8 ; i++, to++, from++ ) {
-		unsigned long *t = (unsigned long *)to;
+		unsigned long __user *t = (unsigned long __user *)to;
 		unsigned long *f = (unsigned long *)from;
 
 		if (__put_user(*f, t) ||
@@ -281,7 +280,7 @@ static int convert_fxsr_from_user( struct i387_fxsave_struct *fxsave,
 	from = &buf->_st[0];
 	for ( i = 0 ; i < 8 ; i++, to++, from++ ) {
 		unsigned long *t = (unsigned long *)to;
-		unsigned long *f = (unsigned long *)from;
+		unsigned long __user *f = (unsigned long __user *)from;
 
 		if (__get_user(*t, f) ||
 				__get_user(*(t + 1), f + 1) ||
@@ -330,13 +329,13 @@ static int save_i387_fxsave( struct _fpstate __user *buf )
 
 int save_i387( struct _fpstate __user *buf )
 {
-	if ( !current->used_math )
+	if ( !used_math() )
 		return 0;
 
 	/* This will cause a "finit" to be triggered by the next
 	 * attempted FPU operation by the 'current' process.
 	 */
-	current->used_math = 0;
+	clear_used_math();
 
 	if ( HAVE_HWFP ) {
 		if ( cpu_has_fxsr ) {
@@ -382,7 +381,7 @@ int restore_i387( struct _fpstate __user *buf )
 	} else {
 		err = restore_i387_soft( &current->thread.i387.soft, buf );
 	}
-	current->used_math = 1;
+	set_used_math();
 	return err;
 }
 
@@ -506,7 +505,7 @@ int dump_fpu( struct pt_regs *regs, struct user_i387_struct *fpu )
 	int fpvalid;
 	struct task_struct *tsk = current;
 
-	fpvalid = tsk->used_math;
+	fpvalid = !!used_math();
 	if ( fpvalid ) {
 		unlazy_fpu( tsk );
 		if ( cpu_has_fxsr ) {
@@ -518,25 +517,11 @@ int dump_fpu( struct pt_regs *regs, struct user_i387_struct *fpu )
 
 	return fpvalid;
 }
-
-int dump_extended_fpu( struct pt_regs *regs, struct user_fxsr_struct *fpu )
-{
-	int fpvalid;
-	struct task_struct *tsk = current;
-
-	fpvalid = tsk->used_math && cpu_has_fxsr;
-	if ( fpvalid ) {
-		unlazy_fpu( tsk );
-		memcpy( fpu, &tsk->thread.i387.fxsave,
-			sizeof(struct user_fxsr_struct) );
-	}
-
-	return fpvalid;
-}
+EXPORT_SYMBOL(dump_fpu);
 
 int dump_task_fpu(struct task_struct *tsk, struct user_i387_struct *fpu)
 {
-	int fpvalid = tsk->used_math;
+	int fpvalid = !!tsk_used_math(tsk);
 
 	if (fpvalid) {
 		if (tsk == current)
@@ -551,7 +536,7 @@ int dump_task_fpu(struct task_struct *tsk, struct user_i387_struct *fpu)
 
 int dump_task_extended_fpu(struct task_struct *tsk, struct user_fxsr_struct *fpu)
 {
-	int fpvalid = tsk->used_math && cpu_has_fxsr;
+	int fpvalid = tsk_used_math(tsk) && cpu_has_fxsr;
 
 	if (fpvalid) {
 		if (tsk == current)