x86/fpu: Rename xstate copy functions which are related to UABI

Rename them to reflect that these functions deal with user space format
XSAVE buffers.

      copy_kernel_to_xstate() -> copy_uabi_from_kernel_to_xstate()
      copy_user_to_xstate()   -> copy_sigframe_from_user_to_xstate()

Again a clear statement that these functions deal with user space ABI.
Suggested-by: Andy Lutomirski <luto@kernel.org>
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/20210623121454.318485015@linutronix.de

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

@@ -102,8 +102,8 @@ extern void __init update_regset_xstate_info(unsigned int size,
 
 void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr);
 int xfeature_size(int xfeature_nr);
-int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf);
-int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf);
+int copy_uabi_from_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf);
+int copy_sigframe_from_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf);
 void copy_dynamic_supervisor_to_kernel(struct xregs_state *xstate, u64 mask);
 void copy_kernel_to_dynamic_supervisor(struct xregs_state *xstate, u64 mask);
 

arch/x86/kernel/fpu/regset.c

@@ -166,7 +166,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
 	}
 
 	fpu_force_restore(fpu);
-	ret = copy_kernel_to_xstate(&fpu->state.xsave, kbuf ?: tmpbuf);
+	ret = copy_uabi_from_kernel_to_xstate(&fpu->state.xsave, kbuf ?: tmpbuf);
 
 out:
 	vfree(tmpbuf);

arch/x86/kernel/fpu/signal.c

@@ -422,7 +422,7 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size)
 	if (use_xsave() && !fx_only) {
 		u64 init_bv = xfeatures_mask_user() & ~user_xfeatures;
 
-		ret = copy_user_to_xstate(&fpu->state.xsave, buf_fx);
+		ret = copy_sigframe_from_user_to_xstate(&fpu->state.xsave, buf_fx);
 		if (ret)
 			goto out;
 

arch/x86/kernel/fpu/xstate.c

@@ -1099,7 +1099,7 @@ static inline bool mxcsr_valid(struct xstate_header *hdr, const u32 *mxcsr)
  * Convert from a ptrace standard-format kernel buffer to kernel XSAVE[S] format
  * and copy to the target thread. This is called from xstateregs_set().
  */
-int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
+int copy_uabi_from_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
 {
 	unsigned int offset, size;
 	int i;
@@ -1154,7 +1154,8 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
  * XSAVE[S] format and copy to the target thread. This is called from the
  * sigreturn() and rt_sigreturn() system calls.
  */
-int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf)
+int copy_sigframe_from_user_to_xstate(struct xregs_state *xsave,
+				      const void __user *ubuf)
 {
 	unsigned int offset, size;
 	int i;