x86/mm/cpa: Move CLFLUSH test into cpa_flush_range()

Rather than guarding all cpa_flush_range() uses with a CLFLUSH test,
put it inside.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Cc: Bin Yang <bin.yang@intel.com>
Cc: Mark Gross <mark.gross@intel.com>
Link: https://lkml.kernel.org/r/20180919085948.036195503@infradead.org

arch/x86/mm/pageattr.c

@@ -293,6 +293,11 @@ static void cpa_flush_range(unsigned long start, int numpages, int cache)
 	BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
 	WARN_ON(PAGE_ALIGN(start) != start);
 
+	if (!static_cpu_has(X86_FEATURE_CLFLUSH)) {
+		cpa_flush_all(cache);
+		return;
+	}
+
 	flush_tlb_kernel_range(start, start + PAGE_SIZE * numpages);
 
 	if (!cache)
@@ -2078,10 +2083,7 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
 	/*
 	 * Before changing the encryption attribute, we need to flush caches.
 	 */
-	if (static_cpu_has(X86_FEATURE_CLFLUSH))
 	cpa_flush_range(start, numpages, 1);
-	else
-		cpa_flush_all(1);
 
 	ret = __change_page_attr_set_clr(&cpa, 1);
 
@@ -2092,10 +2094,7 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
 	 * in case TLB flushing gets optimized in the cpa_flush_range()
 	 * path use the same logic as above.
 	 */
-	if (static_cpu_has(X86_FEATURE_CLFLUSH))
 	cpa_flush_range(start, numpages, 0);
-	else
-		cpa_flush_all(0);
 
 	return ret;
 }