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>

diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c
index 573a9a2..5afff0e 100644 (file)
--- a/arch/powerpc/mm/pgtable-radix.c
+++ b/arch/powerpc/mm/pgtable-radix.c
@@ -56,6 +56,50 @@ static __ref void *early_alloc_pgtable(unsigned long size)
        return pt;
 }
 
+static int early_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;
+
+       pgdp = pgd_offset_k(ea);
+       if (pgd_none(*pgdp)) {
+               pudp = early_alloc_pgtable(PUD_TABLE_SIZE);
+               BUG_ON(pudp == NULL);
+               pgd_populate(&init_mm, pgdp, pudp);
+       }
+       pudp = pud_offset(pgdp, ea);
+       if (map_page_size == PUD_SIZE) {
+               ptep = (pte_t *)pudp;
+               goto set_the_pte;
+       }
+       if (pud_none(*pudp)) {
+               pmdp = early_alloc_pgtable(PMD_TABLE_SIZE);
+               BUG_ON(pmdp == NULL);
+               pud_populate(&init_mm, pudp, pmdp);
+       }
+       pmdp = pmd_offset(pudp, ea);
+       if (map_page_size == PMD_SIZE) {
+               ptep = pmdp_ptep(pmdp);
+               goto set_the_pte;
+       }
+       if (!pmd_present(*pmdp)) {
+               ptep = early_alloc_pgtable(PAGE_SIZE);
+               BUG_ON(ptep == NULL);
+               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)
@@ -68,54 +112,28 @@ int radix__map_kernel_page(unsigned long ea, unsigned long pa,
         * 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);
-                       BUG_ON(pudp == NULL);
-                       pgd_populate(&init_mm, pgdp, pudp);
-               }
-               pudp = pud_offset(pgdp, ea);
-               if (map_page_size == PUD_SIZE) {
-                       ptep = (pte_t *)pudp;
-                       goto set_the_pte;
-               }
-               if (pud_none(*pudp)) {
-                       pmdp = early_alloc_pgtable(PMD_TABLE_SIZE);
-                       BUG_ON(pmdp == NULL);
-                       pud_populate(&init_mm, pudp, pmdp);
-               }
-               pmdp = pmd_offset(pudp, ea);
-               if (map_page_size == PMD_SIZE) {
-                       ptep = pmdp_ptep(pmdp);
-                       goto set_the_pte;
-               }
-               if (!pmd_present(*pmdp)) {
-                       ptep = early_alloc_pgtable(PAGE_SIZE);
-                       BUG_ON(ptep == NULL);
-                       pmd_populate_kernel(&init_mm, pmdp, ptep);
-               }
-               ptep = pte_offset_kernel(pmdp, ea);
+
+       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));