x86/math-emu: Convert to fpstate

Convert math emulation code to the new register storage
mechanism in preparation for dynamically sized buffers.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211013145322.711347464@linutronix.de

arch/x86/math-emu/fpu_aux.c

@@ -53,7 +53,7 @@ void fpstate_init_soft(struct swregs_state *soft)
 
 void finit(void)
 {
-	fpstate_init_soft(&current->thread.fpu.state.soft);
+	fpstate_init_soft(&current->thread.fpu.fpstate->regs.soft);
 }
 
 /*

arch/x86/math-emu/fpu_entry.c

@@ -640,7 +640,7 @@ int fpregs_soft_set(struct task_struct *target,
 		    unsigned int pos, unsigned int count,
 		    const void *kbuf, const void __user *ubuf)
 {
-	struct swregs_state *s387 = &target->thread.fpu.state.soft;
+	struct swregs_state *s387 = &target->thread.fpu.fpstate->regs.soft;
 	void *space = s387->st_space;
 	int ret;
 	int offset, other, i, tags, regnr, tag, newtop;
@@ -691,7 +691,7 @@ int fpregs_soft_get(struct task_struct *target,
 		    const struct user_regset *regset,
 		    struct membuf to)
 {
-	struct swregs_state *s387 = &target->thread.fpu.state.soft;
+	struct swregs_state *s387 = &target->thread.fpu.fpstate->regs.soft;
 	const void *space = s387->st_space;
 	int offset = (S387->ftop & 7) * 10, other = 80 - offset;
 

arch/x86/math-emu/fpu_system.h

@@ -73,7 +73,7 @@ static inline bool seg_writable(struct desc_struct *d)
 	return (d->type & SEG_TYPE_EXECUTE_MASK) == SEG_TYPE_WRITABLE;
 }
 
-#define I387			(&current->thread.fpu.state)
+#define I387			(&current->thread.fpu.fpstate->regs)
 #define FPU_info		(I387->soft.info)
 
 #define FPU_CS			(*(unsigned short *) &(FPU_info->regs->cs))