Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, mm: Unify kernel_physical_mapping_init() API
  x86, mm: Allow highmem user page tables to be disabled at boot time
  x86: Do not reserve brk for DMI if it's not going to be used
  x86: Convert tlbstate_lock to raw_spinlock
  x86: Use the generic page_is_ram()
  x86: Remove BIOS data range from e820
  Move page_is_ram() declaration to mm.h
  Generic page_is_ram: use __weak
  resources: introduce generic page_is_ram()

1 files changed, 26 insertions, 5 deletions

diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index ed34f5e35999..c9ba9deafe83 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -6,6 +6,14 @@
 
 #define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO
 
+#ifdef CONFIG_HIGHPTE
+#define PGALLOC_USER_GFP __GFP_HIGHMEM
+#else
+#define PGALLOC_USER_GFP 0
+#endif
+
+gfp_t __userpte_alloc_gfp = PGALLOC_GFP | PGALLOC_USER_GFP;
+
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
 	return (pte_t *)__get_free_page(PGALLOC_GFP);
@@ -15,16 +23,29 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
 {
 	struct page *pte;
 
-#ifdef CONFIG_HIGHPTE
-	pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
-#else
-	pte = alloc_pages(PGALLOC_GFP, 0);
-#endif
+	pte = alloc_pages(__userpte_alloc_gfp, 0);
 	if (pte)
 		pgtable_page_ctor(pte);
 	return pte;
 }
 
+static int __init setup_userpte(char *arg)
+{
+	if (!arg)
+		return -EINVAL;
+
+	/*
+	 * "userpte=nohigh" disables allocation of user pagetables in
+	 * high memory.
+	 */
+	if (strcmp(arg, "nohigh") == 0)
+		__userpte_alloc_gfp &= ~__GFP_HIGHMEM;
+	else
+		return -EINVAL;
+	return 0;
+}
+early_param("userpte", setup_userpte);
+
 void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte)
 {
 	pgtable_page_dtor(pte);