x86/tlb: Move __flush_tlb_all() out of line

Reduce the number of required exports to one and make flush_tlb_global()
static to the TLB code.

flush_tlb_local() cannot be confined to the TLB code as the MTRR
handling requires a PGE-less flush.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200421092559.740388137@linutronix.de

arch/x86/include/asm/tlbflush.h

@@ -142,8 +142,8 @@ static inline unsigned long build_cr3_noflush(pgd_t *pgd, u16 asid)
 
 struct flush_tlb_info;
 
+void __flush_tlb_all(void);
 void flush_tlb_local(void);
-void flush_tlb_global(void);
 void flush_tlb_one_user(unsigned long addr);
 void flush_tlb_one_kernel(unsigned long addr);
 void flush_tlb_others(const struct cpumask *cpumask,
@@ -341,27 +341,6 @@ static inline void cr4_set_bits_and_update_boot(unsigned long mask)
 
 extern void initialize_tlbstate_and_flush(void);
 
-/*
- * flush everything
- */
-static inline void __flush_tlb_all(void)
-{
-	/*
-	 * This is to catch users with enabled preemption and the PGE feature
-	 * and don't trigger the warning in __native_flush_tlb().
-	 */
-	VM_WARN_ON_ONCE(preemptible());
-
-	if (boot_cpu_has(X86_FEATURE_PGE)) {
-		flush_tlb_global();
-	} else {
-		/*
-		 * !PGE -> !PCID (setup_pcid()), thus every flush is total.
-		 */
-		flush_tlb_local();
-	}
-}
-
 #define TLB_FLUSH_ALL	-1UL
 
 /*

arch/x86/mm/tlb.c

@@ -1018,12 +1018,6 @@ STATIC_NOPV void native_flush_tlb_global(void)
 	raw_local_irq_restore(flags);
 }
 
-void flush_tlb_global(void)
-{
-	__flush_tlb_global();
-}
-EXPORT_SYMBOL_GPL(flush_tlb_global);
-
 /*
  * Flush the entire current user mapping
  */
@@ -1046,7 +1040,28 @@ void flush_tlb_local(void)
 {
 	__flush_tlb_local();
 }
-EXPORT_SYMBOL_GPL(flush_tlb_local);
+
+/*
+ * Flush everything
+ */
+void __flush_tlb_all(void)
+{
+	/*
+	 * This is to catch users with enabled preemption and the PGE feature
+	 * and don't trigger the warning in __native_flush_tlb().
+	 */
+	VM_WARN_ON_ONCE(preemptible());
+
+	if (boot_cpu_has(X86_FEATURE_PGE)) {
+		__flush_tlb_global();
+	} else {
+		/*
+		 * !PGE -> !PCID (setup_pcid()), thus every flush is total.
+		 */
+		flush_tlb_local();
+	}
+}
+EXPORT_SYMBOL_GPL(__flush_tlb_all);
 
 /*
  * arch_tlbbatch_flush() performs a full TLB flush regardless of the active mm.