4 files changed, 31 insertions, 8 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index aef63c8e3d2d..370f47787122 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1054,6 +1054,11 @@ config HIGHMEM
 
           If unsure, say n.
 
+config HIGHPTE
+        bool "Allocate 2nd-level pagetables from highmem"
+        depends on HIGHMEM
+        depends on !OUTER_CACHE
+
 source "mm/Kconfig"
 
 config LEDS
diff --git a/arch/arm/include/asm/pgalloc.h b/arch/arm/include/asm/pgalloc.h
index 3dcd64bf1824..b12cc98bbe04 100644
--- a/arch/arm/include/asm/pgalloc.h
+++ b/arch/arm/include/asm/pgalloc.h
@@ -36,6 +36,8 @@ extern void free_pgd_slow(struct mm_struct *mm, pgd_t *pgd);
 #define pgd_alloc(mm)                   get_pgd_slow(mm)
 #define pgd_free(mm, pgd)               free_pgd_slow(mm, pgd)
 
+#define PGALLOC_GFP     (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO)
+
 /*
  * Allocate one PTE table.
  *
@@ -57,7 +59,7 @@ pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
 {
         pte_t *pte;
 
-        pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+        pte = (pte_t *)__get_free_page(PGALLOC_GFP);
         if (pte) {
                 clean_dcache_area(pte, sizeof(pte_t) * PTRS_PER_PTE);
                 pte += PTRS_PER_PTE;
@@ -71,10 +73,16 @@ pte_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
         struct page *pte;
 
-        pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
+#ifdef CONFIG_HIGHPTE
+        pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
+#else
+        pte = alloc_pages(PGALLOC_GFP, 0);
+#endif
         if (pte) {
-                void *page = page_address(pte);
-                clean_dcache_area(page, sizeof(pte_t) * PTRS_PER_PTE);
+                if (!PageHighMem(pte)) {
+                        void *page = page_address(pte);
+                        clean_dcache_area(page, sizeof(pte_t) * PTRS_PER_PTE);
+                }
                 pgtable_page_ctor(pte);
         }
 
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index 9655bce3d345..201ccaa11f61 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -262,10 +262,19 @@ extern struct page *empty_zero_page;
 #define pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0)
 #define pte_page(pte)           (pfn_to_page(pte_pfn(pte)))
 #define pte_offset_kernel(dir,addr)     (pmd_page_vaddr(*(dir)) + __pte_index(addr))
-#define pte_offset_map(dir,addr)        (pmd_page_vaddr(*(dir)) + __pte_index(addr))
-#define pte_offset_map_nested(dir,addr) (pmd_page_vaddr(*(dir)) + __pte_index(addr))
-#define pte_unmap(pte)          do { } while (0)
-#define pte_unmap_nested(pte)   do { } while (0)
+
+#define pte_offset_map(dir,addr)        (__pte_map(dir, KM_PTE0) + __pte_index(addr))
+#define pte_offset_map_nested(dir,addr) (__pte_map(dir, KM_PTE1) + __pte_index(addr))
+#define pte_unmap(pte)                  __pte_unmap(pte, KM_PTE0)
+#define pte_unmap_nested(pte)           __pte_unmap(pte, KM_PTE1)
+
+#ifndef CONFIG_HIGHPTE
+#define __pte_map(dir,km)       pmd_page_vaddr(*(dir))
+#define __pte_unmap(pte,km)     do { } while (0)
+#else
+#define __pte_map(dir,km)       ((pte_t *)kmap_atomic(pmd_page(*(dir)), km) + PTRS_PER_PTE)
+#define __pte_unmap(pte,km)     kunmap_atomic((pte - PTRS_PER_PTE), km)
+#endif
 
 #define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,pte,ext)
 
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 6fdcbb709827..5fa8dea5a371 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -16,6 +16,7 @@
 #include <linux/kprobes.h>
 #include <linux/uaccess.h>
 #include <linux/page-flags.h>
+#include <linux/highmem.h>
 
 #include <asm/system.h>
 #include <asm/pgtable.h>