x86/fpu: Rename fregs-related copy functions

The function names for fnsave/fnrstor operations are horribly named and
a permanent source of confusion.

Rename:
	copy_kernel_to_fregs() to frstor()
	copy_fregs_to_user()   to fnsave_to_user_sigframe()
	copy_user_to_fregs()   to frstor_from_user_sigframe()

so it's clear what these are doing. All these functions are really low
level wrappers around the equally named instructions, so mapping to the
documentation is just natural.

No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121454.223594101@linutronix.de

arch/x86/include/asm/fpu/internal.h

@@ -124,7 +124,7 @@ static inline void fpstate_init_soft(struct swregs_state *soft) {}
 		     _ASM_EXTABLE_HANDLE(1b, 2b, ex_handler_fprestore)	\
 		     : output : input)
 
-static inline int copy_fregs_to_user(struct fregs_state __user *fx)
+static inline int fnsave_to_user_sigframe(struct fregs_state __user *fx)
 {
 	return user_insn(fnsave %[fx]; fwait,  [fx] "=m" (*fx), "m" (*fx));
 }
@@ -162,17 +162,17 @@ static inline int fxrstor_from_user_sigframe(struct fxregs_state __user *fx)
 		return user_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
 }
 
-static inline void copy_kernel_to_fregs(struct fregs_state *fx)
+static inline void frstor(struct fregs_state *fx)
 {
 	kernel_insn(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
 }
 
-static inline int copy_kernel_to_fregs_err(struct fregs_state *fx)
+static inline int frstor_safe(struct fregs_state *fx)
 {
 	return kernel_insn_err(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
 }
 
-static inline int copy_user_to_fregs(struct fregs_state __user *fx)
+static inline int frstor_from_user_sigframe(struct fregs_state __user *fx)
 {
 	return user_insn(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
 }
@@ -385,7 +385,7 @@ static inline void __copy_kernel_to_fpregs(union fpregs_state *fpstate, u64 mask
 		if (use_fxsr())
 			fxrstor(&fpstate->fxsave);
 		else
-			copy_kernel_to_fregs(&fpstate->fsave);
+			frstor(&fpstate->fsave);
 	}
 }
 

arch/x86/kernel/fpu/core.c

@@ -318,7 +318,7 @@ static inline void copy_init_fpstate_to_fpregs(u64 features_mask)
 	else if (use_fxsr())
 		fxrstor(&init_fpstate.fxsave);
 	else
-		copy_kernel_to_fregs(&init_fpstate.fsave);
+		frstor(&init_fpstate.fsave);
 
 	if (boot_cpu_has(X86_FEATURE_OSPKE))
 		copy_init_pkru_to_fpregs();

arch/x86/kernel/fpu/signal.c

@@ -133,7 +133,7 @@ static inline int copy_fpregs_to_sigframe(struct xregs_state __user *buf)
 	else if (use_fxsr())
 		err = fxsave_to_user_sigframe((struct fxregs_state __user *) buf);
 	else
-		err = copy_fregs_to_user((struct fregs_state __user *) buf);
+		err = fnsave_to_user_sigframe((struct fregs_state __user *) buf);
 
 	if (unlikely(err) && __clear_user(buf, fpu_user_xstate_size))
 		err = -EFAULT;
@@ -274,7 +274,7 @@ static int copy_user_to_fpregs_zeroing(void __user *buf, u64 xbv, int fx_only)
 	} else if (use_fxsr()) {
 		return fxrstor_from_user_sigframe(buf);
 	} else
-		return copy_user_to_fregs(buf);
+		return frstor_from_user_sigframe(buf);
 }
 
 static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size)
@@ -465,7 +465,7 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size)
 			goto out;
 
 		fpregs_lock();
-		ret = copy_kernel_to_fregs_err(&fpu->state.fsave);
+		ret = frstor_safe(&fpu->state.fsave);
 	}
 	if (!ret)
 		fpregs_mark_activate();