ARM: pgtable: add pud-level code

Add pud_offset() et.al. between the pgd and pmd code in preparation of
using pgtable-nopud.h rather than 4level-fixup.h.

This incorporates a fix from Jamie Iles <jamie@jamieiles.com> for
uaccess_with_memcpy.c.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

9 files changed, 116 insertions, 22 deletions

diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index ca567914d303..5750704e0271 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -301,6 +301,7 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
 #define pgd_present(pgd)        (1)
 #define pgd_clear(pgdp)         do { } while (0)
 #define set_pgd(pgd,pgdp)       do { } while (0)
+#define set_pud(pud,pudp)       do { } while (0)
 
 
 /* Find an entry in the second-level page table.. */
diff --git a/arch/arm/lib/uaccess_with_memcpy.c b/arch/arm/lib/uaccess_with_memcpy.c
index e2d2f2cd0c4f..8b9b13649f81 100644
--- a/arch/arm/lib/uaccess_with_memcpy.c
+++ b/arch/arm/lib/uaccess_with_memcpy.c
@@ -27,13 +27,18 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp)
         pgd_t *pgd;
         pmd_t *pmd;
         pte_t *pte;
+        pud_t *pud;
         spinlock_t *ptl;
 
         pgd = pgd_offset(current->mm, addr);
         if (unlikely(pgd_none(*pgd) || pgd_bad(*pgd)))
                 return 0;
 
-        pmd = pmd_offset(pgd, addr);
+        pud = pud_offset(pgd, addr);
+        if (unlikely(pud_none(*pud) || pud_bad(*pud)))
+                return 0;
+
+        pmd = pmd_offset(pud, addr);
         if (unlikely(pmd_none(*pmd) || pmd_bad(*pmd)))
                 return 0;
 
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index ac6a36142fcd..a9bdfcda23f4 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -148,6 +148,7 @@ static int __init consistent_init(void)
 {
         int ret = 0;
         pgd_t *pgd;
+        pud_t *pud;
         pmd_t *pmd;
         pte_t *pte;
         int i = 0;
@@ -155,7 +156,15 @@ static int __init consistent_init(void)
 
         do {
                 pgd = pgd_offset(&init_mm, base);
-                pmd = pmd_alloc(&init_mm, pgd, base);
+
+                pud = pud_alloc(&init_mm, pgd, base);
+                if (!pud) {
+                        printk(KERN_ERR "%s: no pud tables\n", __func__);
+                        ret = -ENOMEM;
+                        break;
+                }
+
+                pmd = pmd_alloc(&init_mm, pud, base);
                 if (!pmd) {
                         printk(KERN_ERR "%s: no pmd tables\n", __func__);
                         ret = -ENOMEM;
diff --git a/arch/arm/mm/fault-armv.c b/arch/arm/mm/fault-armv.c
index 01210dba0221..7cab79179421 100644
--- a/arch/arm/mm/fault-armv.c
+++ b/arch/arm/mm/fault-armv.c
@@ -95,6 +95,7 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address,
 {
         spinlock_t *ptl;
         pgd_t *pgd;
+        pud_t *pud;
         pmd_t *pmd;
         pte_t *pte;
         int ret;
@@ -103,7 +104,11 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address,
         if (pgd_none_or_clear_bad(pgd))
                 return 0;
 
-        pmd = pmd_offset(pgd, address);
+        pud = pud_offset(pgd, address);
+        if (pud_none_or_clear_bad(pud))
+                return 0;
+
+        pmd = pmd_offset(pud, address);
         if (pmd_none_or_clear_bad(pmd))
                 return 0;
 
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index ef0e24f578ef..bc0e1d88fd3b 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -80,6 +80,7 @@ void show_pte(struct mm_struct *mm, unsigned long addr)
                         addr, (long long)pgd_val(*pgd));
 
         do {
+                pud_t *pud;
                 pmd_t *pmd;
                 pte_t *pte;
 
@@ -91,7 +92,19 @@ void show_pte(struct mm_struct *mm, unsigned long addr)
                         break;
                 }
 
-                pmd = pmd_offset(pgd, addr);
+                pud = pud_offset(pgd, addr);
+                if (PTRS_PER_PUD != 1)
+                        printk(", *pud=%08lx", pud_val(*pud));
+
+                if (pud_none(*pud))
+                        break;
+
+                if (pud_bad(*pud)) {
+                        printk("(bad)");
+                        break;
+                }
+
+                pmd = pmd_offset(pud, addr);
                 if (PTRS_PER_PMD != 1)
                         printk(", *pmd=%08llx", (long long)pmd_val(*pmd));
 
@@ -390,6 +403,7 @@ do_translation_fault(unsigned long addr, unsigned int fsr,
 {
         unsigned int index;
         pgd_t *pgd, *pgd_k;
+        pud_t *pud, *pud_k;
         pmd_t *pmd, *pmd_k;
 
         if (addr < TASK_SIZE)
@@ -408,12 +422,19 @@ do_translation_fault(unsigned long addr, unsigned int fsr,
 
         if (pgd_none(*pgd_k))
                 goto bad_area;
-
         if (!pgd_present(*pgd))
                 set_pgd(pgd, *pgd_k);
 
-        pmd_k = pmd_offset(pgd_k, addr);
-        pmd   = pmd_offset(pgd, addr);
+        pud = pud_offset(pgd, addr);
+        pud_k = pud_offset(pgd_k, addr);
+
+        if (pud_none(*pud_k))
+                goto bad_area;
+        if (!pud_present(*pud))
+                set_pud(pud, *pud_k);
+
+        pmd = pmd_offset(pud, addr);
+        pmd_k = pmd_offset(pud_k, addr);
 
         /*
          * On ARM one Linux PGD entry contains two hardware entries (see page
diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c
index 57299446f787..2be9139a4ef3 100644
--- a/arch/arm/mm/idmap.c
+++ b/arch/arm/mm/idmap.c
@@ -4,10 +4,10 @@
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
 
-static void idmap_add_pmd(pgd_t *pgd, unsigned long addr, unsigned long end,
+static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end,
         unsigned long prot)
 {
-        pmd_t *pmd = pmd_offset(pgd, addr);
+        pmd_t *pmd = pmd_offset(pud, addr);
 
         addr = (addr & PMD_MASK) | prot;
         pmd[0] = __pmd(addr);
@@ -16,6 +16,18 @@ static void idmap_add_pmd(pgd_t *pgd, unsigned long addr, unsigned long end,
         flush_pmd_entry(pmd);
 }
 
+static void idmap_add_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
+        unsigned long prot)
+{
+        pud_t *pud = pud_offset(pgd, addr);
+        unsigned long next;
+
+        do {
+                next = pud_addr_end(addr, end);
+                idmap_add_pmd(pud, addr, next, prot);
+        } while (pud++, addr = next, addr != end);
+}
+
 void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
 {
         unsigned long prot, next;
@@ -27,17 +39,28 @@ void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
         pgd += pgd_index(addr);
         do {
                 next = pgd_addr_end(addr, end);
-                idmap_add_pmd(pgd, addr, next, prot);
+                idmap_add_pud(pgd, addr, next, prot);
         } while (pgd++, addr = next, addr != end);
 }
 
 #ifdef CONFIG_SMP
-static void idmap_del_pmd(pgd_t *pgd, unsigned long addr, unsigned long end)
+static void idmap_del_pmd(pud_t *pud, unsigned long addr, unsigned long end)
 {
-        pmd_t *pmd = pmd_offset(pgd, addr);
+        pmd_t *pmd = pmd_offset(pud, addr);
         pmd_clear(pmd);
 }
 
+static void idmap_del_pud(pgd_t *pgd, unsigned long addr, unsigned long end)
+{
+        pud_t *pud = pud_offset(pgd, addr);
+        unsigned long next;
+
+        do {
+                next = pud_addr_end(addr, end);
+                idmap_del_pmd(pud, addr, next);
+        } while (pud++, addr = next, addr != end);
+}
+
 void identity_mapping_del(pgd_t *pgd, unsigned long addr, unsigned long end)
 {
         unsigned long next;
@@ -45,7 +68,7 @@ void identity_mapping_del(pgd_t *pgd, unsigned long addr, unsigned long end)
         pgd += pgd_index(addr);
         do {
                 next = pgd_addr_end(addr, end);
-                idmap_del_pmd(pgd, addr, next);
+                idmap_del_pud(pgd, addr, next);
         } while (pgd++, addr = next, addr != end);
 }
 #endif
diff --git a/arch/arm/mm/mm.h b/arch/arm/mm/mm.h
index 36960df5fb76..d2384106af9c 100644
--- a/arch/arm/mm/mm.h
+++ b/arch/arm/mm/mm.h
@@ -7,7 +7,7 @@ extern pmd_t *top_pmd;
 
 static inline pmd_t *pmd_off(pgd_t *pgd, unsigned long virt)
 {
-        return pmd_offset(pgd, virt);
+        return pmd_offset(pud_offset(pgd, virt), virt);
 }
 
 static inline pmd_t *pmd_off_k(unsigned long virt)
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 176749010935..82ef6966ae09 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -550,11 +550,11 @@ static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
         } while (pte++, addr += PAGE_SIZE, addr != end);
 }
 
-static void __init alloc_init_section(pgd_t *pgd, unsigned long addr,
+static void __init alloc_init_section(pud_t *pud, unsigned long addr,
                                       unsigned long end, phys_addr_t phys,
                                       const struct mem_type *type)
 {
-        pmd_t *pmd = pmd_offset(pgd, addr);
+        pmd_t *pmd = pmd_offset(pud, addr);
 
         /*
          * Try a section mapping - end, addr and phys must all be aligned
@@ -583,6 +583,19 @@ static void __init alloc_init_section(pgd_t *pgd, unsigned long addr,
         }
 }
 
+static void alloc_init_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
+        unsigned long phys, const struct mem_type *type)
+{
+        pud_t *pud = pud_offset(pgd, addr);
+        unsigned long next;
+
+        do {
+                next = pud_addr_end(addr, end);
+                alloc_init_section(pud, addr, next, phys, type);
+                phys += next - addr;
+        } while (pud++, addr = next, addr != end);
+}
+
 static void __init create_36bit_mapping(struct map_desc *md,
                                         const struct mem_type *type)
 {
@@ -630,7 +643,8 @@ static void __init create_36bit_mapping(struct map_desc *md,
         pgd = pgd_offset_k(addr);
         end = addr + length;
         do {
-                pmd_t *pmd = pmd_offset(pgd, addr);
+                pud_t *pud = pud_offset(pgd, addr);
+                pmd_t *pmd = pmd_offset(pud, addr);
                 int i;
 
                 for (i = 0; i < 16; i++)
@@ -696,7 +710,7 @@ static void __init create_mapping(struct map_desc *md)
         do {
                 unsigned long next = pgd_addr_end(addr, end);
 
-                alloc_init_section(pgd, addr, next, phys, type);
+                alloc_init_pud(pgd, addr, next, phys, type);
 
                 phys += next - addr;
                 addr = next;
diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c
index 93292a18cf77..f7fafb1741f4 100644
--- a/arch/arm/mm/pgd.c
+++ b/arch/arm/mm/pgd.c
@@ -23,6 +23,7 @@
 pgd_t *pgd_alloc(struct mm_struct *mm)
 {
         pgd_t *new_pgd, *init_pgd;
+        pud_t *new_pud, *init_pud;
         pmd_t *new_pmd, *init_pmd;
         pte_t *new_pte, *init_pte;
 
@@ -46,7 +47,11 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
                  * On ARM, first page must always be allocated since it
                  * contains the machine vectors.
                  */
-                new_pmd = pmd_alloc(mm, new_pgd, 0);
+                new_pud = pud_alloc(mm, new_pgd, 0);
+                if (!new_pud)
+                        goto no_pud;
+
+                new_pmd = pmd_alloc(mm, new_pud, 0);
                 if (!new_pmd)
                         goto no_pmd;
 
@@ -54,7 +59,8 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
                 if (!new_pte)
                         goto no_pte;
 
-                init_pmd = pmd_offset(init_pgd, 0);
+                init_pud = pud_offset(init_pgd, 0);
+                init_pmd = pmd_offset(init_pud, 0);
                 init_pte = pte_offset_map(init_pmd, 0);
                 set_pte_ext(new_pte, *init_pte, 0);
                 pte_unmap(init_pte);
@@ -66,6 +72,8 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
 no_pte:
         pmd_free(mm, new_pmd);
 no_pmd:
+        pud_free(mm, new_pud);
+no_pud:
         free_pages((unsigned long)new_pgd, 2);
 no_pgd:
         return NULL;
@@ -74,6 +82,7 @@ no_pgd:
 void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
 {
         pgd_t *pgd;
+        pud_t *pud;
         pmd_t *pmd;
         pgtable_t pte;
 
@@ -84,7 +93,11 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
         if (pgd_none_or_clear_bad(pgd))
                 goto no_pgd;
 
-        pmd = pmd_offset(pgd, 0);
+        pud = pud_offset(pgd, 0);
+        if (pud_none_or_clear_bad(pud))
+                goto no_pud;
+
+        pmd = pmd_offset(pud, 0);
         if (pmd_none_or_clear_bad(pmd))
                 goto no_pmd;
 
@@ -92,8 +105,11 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
         pmd_clear(pmd);
         pte_free(mm, pte);
 no_pmd:
-        pgd_clear(pgd);
+        pud_clear(pud);
         pmd_free(mm, pmd);
+no_pud:
+        pgd_clear(pgd);
+        pud_free(mm, pud);
 no_pgd:
         free_pages((unsigned long) pgd_base, 2);
 }