ARM: split off core mapping logic from create_mapping

In order to be able to reuse the core mapping logic of create_mapping
for mapping the UEFI Runtime Services into a private set of page tables,
split it off from create_mapping() into a separate function
__create_mapping which we will wire up in a subsequent patch.

Tested-by: Ryan Harkin <ryan.harkin@linaro.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

1 files changed, 31 insertions, 25 deletions

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index de19f90221e2..3100de92148b 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -818,7 +818,8 @@ static void __init alloc_init_pud(pgd_t *pgd, unsigned long addr,
 }
 
 #ifndef CONFIG_ARM_LPAE
-static void __init create_36bit_mapping(struct map_desc *md,
+static void __init create_36bit_mapping(struct mm_struct *mm,
+                                        struct map_desc *md,
                                         const struct mem_type *type)
 {
         unsigned long addr, length, end;
@@ -859,7 +860,7 @@ static void __init create_36bit_mapping(struct map_desc *md,
          */
         phys |= (((md->pfn >> (32 - PAGE_SHIFT)) & 0xF) << 20);
 
-        pgd = pgd_offset_k(addr);
+        pgd = pgd_offset(mm, addr);
         end = addr + length;
         do {
                 pud_t *pud = pud_offset(pgd, addr);
@@ -876,33 +877,13 @@ static void __init create_36bit_mapping(struct map_desc *md,
 }
 #endif  /* !CONFIG_ARM_LPAE */
 
-/*
- * Create the page directory entries and any necessary
- * page tables for the mapping specified by `md'.  We
- * are able to cope here with varying sizes and address
- * offsets, and we take full advantage of sections and
- * supersections.
- */
-static void __init create_mapping(struct map_desc *md)
+static void __init __create_mapping(struct mm_struct *mm, struct map_desc *md)
 {
         unsigned long addr, length, end;
         phys_addr_t phys;
         const struct mem_type *type;
         pgd_t *pgd;
 
-        if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
-                pr_warn("BUG: not creating mapping for 0x%08llx at 0x%08lx in user region\n",
-                        (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
-                return;
-        }
-
-        if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
-            md->virtual >= PAGE_OFFSET && md->virtual < FIXADDR_START &&
-            (md->virtual < VMALLOC_START || md->virtual >= VMALLOC_END)) {
-                pr_warn("BUG: mapping for 0x%08llx at 0x%08lx out of vmalloc space\n",
-                        (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
-        }
-
         type = &mem_types[md->type];
 
 #ifndef CONFIG_ARM_LPAE
@@ -910,7 +891,7 @@ static void __init create_mapping(struct map_desc *md)
          * Catch 36-bit addresses
          */
         if (md->pfn >= 0x100000) {
-                create_36bit_mapping(md, type);
+                create_36bit_mapping(mm, md, type);
                 return;
         }
 #endif
@@ -925,7 +906,7 @@ static void __init create_mapping(struct map_desc *md)
                 return;
         }
 
-        pgd = pgd_offset_k(addr);
+        pgd = pgd_offset(mm, addr);
         end = addr + length;
         do {
                 unsigned long next = pgd_addr_end(addr, end);
@@ -938,6 +919,31 @@ static void __init create_mapping(struct map_desc *md)
 }
 
 /*
+ * Create the page directory entries and any necessary
+ * page tables for the mapping specified by `md'.  We
+ * are able to cope here with varying sizes and address
+ * offsets, and we take full advantage of sections and
+ * supersections.
+ */
+static void __init create_mapping(struct map_desc *md)
+{
+        if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
+                pr_warn("BUG: not creating mapping for 0x%08llx at 0x%08lx in user region\n",
+                        (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
+                return;
+        }
+
+        if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
+            md->virtual >= PAGE_OFFSET && md->virtual < FIXADDR_START &&
+            (md->virtual < VMALLOC_START || md->virtual >= VMALLOC_END)) {
+                pr_warn("BUG: mapping for 0x%08llx at 0x%08lx out of vmalloc space\n",
+                        (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
+        }
+
+        __create_mapping(&init_mm, md);
+}
+
+/*
  * Create the architecture specific mappings
  */
 void __init iotable_init(struct map_desc *io_desc, int nr)