x86/fpu: Rename copyin_to_xsaves()/copyout_from_xsaves() to copy_user_to_xstate()/copy_xstate_to_user()

The 'copyin/copyout' nomenclature needlessly departs from what the modern FPU code
uses, which is:

 copy_fpregs_to_fpstate()
 copy_fpstate_to_sigframe()
 copy_fregs_to_user()
 copy_fxregs_to_kernel()
 copy_fxregs_to_user()
 copy_kernel_to_fpregs()
 copy_kernel_to_fregs()
 copy_kernel_to_fxregs()
 copy_kernel_to_xregs()
 copy_user_to_fregs()
 copy_user_to_fxregs()
 copy_user_to_xregs()
 copy_xregs_to_kernel()
 copy_xregs_to_user()

I.e. according to this pattern, the following rename should be done:

  copyin_to_xsaves()    -> copy_user_to_xstate()
  copyout_from_xsaves() -> copy_xstate_to_user()

or, if we want to be pedantic, denote that that the user-space format is ptrace:

  copyin_to_xsaves()    -> copy_user_ptrace_to_xstate()
  copyout_from_xsaves() -> copy_xstate_to_user_ptrace()

But I'd suggest the shorter, non-pedantic name.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-2-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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

@@ -48,8 +48,8 @@ void fpu__xstate_clear_all_cpu_caps(void);
 void *get_xsave_addr(struct xregs_state *xsave, int xstate);
 const void *get_xsave_field_ptr(int xstate_field);
 int using_compacted_format(void);
-int copyout_from_xsaves(unsigned int pos, unsigned int count, void *kbuf,
+int copy_xstate_to_user(unsigned int pos, unsigned int count, void *kbuf,
 			void __user *ubuf, struct xregs_state *xsave);
-int copyin_to_xsaves(const void *kbuf, const void __user *ubuf,
+int copy_user_to_xstate(const void *kbuf, const void __user *ubuf,
 		     struct xregs_state *xsave);
 #endif

arch/x86/kernel/fpu/regset.c

@@ -92,7 +92,7 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset,
 	fpu__activate_fpstate_read(fpu);
 
 	if (using_compacted_format()) {
-		ret = copyout_from_xsaves(pos, count, kbuf, ubuf, xsave);
+		ret = copy_xstate_to_user(pos, count, kbuf, ubuf, xsave);
 	} else {
 		fpstate_sanitize_xstate(fpu);
 		/*
@@ -132,7 +132,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
 	fpu__activate_fpstate_write(fpu);
 
 	if (boot_cpu_has(X86_FEATURE_XSAVES))
-		ret = copyin_to_xsaves(kbuf, ubuf, xsave);
+		ret = copy_user_to_xstate(kbuf, ubuf, xsave);
 	else
 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, xsave, 0, -1);
 

arch/x86/kernel/fpu/signal.c

@@ -324,7 +324,7 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size)
 		fpu__drop(fpu);
 
 		if (using_compacted_format()) {
-			err = copyin_to_xsaves(NULL, buf_fx,
+			err = copy_user_to_xstate(NULL, buf_fx,
 					       &fpu->state.xsave);
 		} else {
 			err = __copy_from_user(&fpu->state.xsave,

arch/x86/kernel/fpu/xstate.c

@@ -951,7 +951,7 @@ static inline int xstate_copyout(unsigned int pos, unsigned int count,
  * zero. This is called from xstateregs_get() and there we check the CPU
  * has XSAVES.
  */
-int copyout_from_xsaves(unsigned int pos, unsigned int count, void *kbuf,
+int copy_xstate_to_user(unsigned int pos, unsigned int count, void *kbuf,
 			void __user *ubuf, struct xregs_state *xsave)
 {
 	unsigned int offset, size;
@@ -1023,7 +1023,7 @@ int copyout_from_xsaves(unsigned int pos, unsigned int count, void *kbuf,
  * there we check the CPU has XSAVES and a whole standard-sized buffer
  * exists.
  */
-int copyin_to_xsaves(const void *kbuf, const void __user *ubuf,
+int copy_user_to_xstate(const void *kbuf, const void __user *ubuf,
 		     struct xregs_state *xsave)
 {
 	unsigned int offset, size;