powerpc/64s/radix: Split early page table mapping to its own function

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/mm/pgtable-radix.c

@@ -56,7 +56,7 @@ static __ref void *early_alloc_pgtable(unsigned long size)
 	return pt;
 }
 
-int radix__map_kernel_page(unsigned long ea, unsigned long pa,
+static int early_map_kernel_page(unsigned long ea, unsigned long pa,
 			  pgprot_t flags,
 			  unsigned int map_page_size)
 {
@@ -64,30 +64,7 @@ int radix__map_kernel_page(unsigned long ea, unsigned long pa,
 	pud_t *pudp;
 	pmd_t *pmdp;
 	pte_t *ptep;
-	/*
-	 * Make sure task size is correct as per the max adddr
-	 */
-	BUILD_BUG_ON(TASK_SIZE_USER64 > RADIX_PGTABLE_RANGE);
-	if (slab_is_available()) {
-		pgdp = pgd_offset_k(ea);
-		pudp = pud_alloc(&init_mm, pgdp, ea);
-		if (!pudp)
-			return -ENOMEM;
-		if (map_page_size == PUD_SIZE) {
-			ptep = (pte_t *)pudp;
-			goto set_the_pte;
-		}
-		pmdp = pmd_alloc(&init_mm, pudp, ea);
-		if (!pmdp)
-			return -ENOMEM;
-		if (map_page_size == PMD_SIZE) {
-			ptep = pmdp_ptep(pmdp);
-			goto set_the_pte;
-		}
-		ptep = pte_alloc_kernel(pmdp, ea);
-		if (!ptep)
-			return -ENOMEM;
-	} else {
+
 	pgdp = pgd_offset_k(ea);
 	if (pgd_none(*pgdp)) {
 		pudp = early_alloc_pgtable(PUD_TABLE_SIZE);
@@ -115,7 +92,48 @@ int radix__map_kernel_page(unsigned long ea, unsigned long pa,
 		pmd_populate_kernel(&init_mm, pmdp, ptep);
 	}
 	ptep = pte_offset_kernel(pmdp, ea);
+
+set_the_pte:
+	set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, flags));
+	smp_wmb();
+	return 0;
+}
+
+
+int radix__map_kernel_page(unsigned long ea, unsigned long pa,
+			  pgprot_t flags,
+			  unsigned int map_page_size)
+{
+	pgd_t *pgdp;
+	pud_t *pudp;
+	pmd_t *pmdp;
+	pte_t *ptep;
+	/*
+	 * Make sure task size is correct as per the max adddr
+	 */
+	BUILD_BUG_ON(TASK_SIZE_USER64 > RADIX_PGTABLE_RANGE);
+
+	if (!slab_is_available())
+		return early_map_kernel_page(ea, pa, flags, map_page_size);
+
+	pgdp = pgd_offset_k(ea);
+	pudp = pud_alloc(&init_mm, pgdp, ea);
+	if (!pudp)
+		return -ENOMEM;
+	if (map_page_size == PUD_SIZE) {
+		ptep = (pte_t *)pudp;
+		goto set_the_pte;
+	}
+	pmdp = pmd_alloc(&init_mm, pudp, ea);
+	if (!pmdp)
+		return -ENOMEM;
+	if (map_page_size == PMD_SIZE) {
+		ptep = pmdp_ptep(pmdp);
+		goto set_the_pte;
 	}
+	ptep = pte_alloc_kernel(pmdp, ea);
+	if (!ptep)
+		return -ENOMEM;
 
 set_the_pte:
 	set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, flags));