[PATCH] Use proper accessors to change PSE bits in change_page_attr()

Use normal pte accessors in change_page_attr() to access the PSE
bits.

Signed-off-by: Andi Kleen <ak@suse.de>

2 files changed, 7 insertions, 10 deletions

diff --git a/arch/x86_64/mm/pageattr.c b/arch/x86_64/mm/pageattr.c
index 01591b649f4e..3e231d762aaa 100644
--- a/arch/x86_64/mm/pageattr.c
+++ b/arch/x86_64/mm/pageattr.c
@@ -108,8 +108,8 @@ static void revert_page(unsigned long address, pgprot_t ref_prot)
         BUG_ON(pud_none(*pud));
         pmd = pmd_offset(pud, address);
         BUG_ON(pmd_val(*pmd) & _PAGE_PSE);
-        pgprot_val(ref_prot) |= _PAGE_PSE;
         large_pte = mk_pte_phys(__pa(address) & LARGE_PAGE_MASK, ref_prot);
+        large_pte = pte_mkhuge(large_pte);
         set_pte((pte_t *)pmd, large_pte);
 }      
 
@@ -119,32 +119,28 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
 { 
         pte_t *kpte; 
         struct page *kpte_page;
-        unsigned kpte_flags;
         pgprot_t ref_prot2;
         kpte = lookup_address(address);
         if (!kpte) return 0;
         kpte_page = virt_to_page(((unsigned long)kpte) & PAGE_MASK);
-        kpte_flags = pte_val(*kpte); 
         if (pgprot_val(prot) != pgprot_val(ref_prot)) { 
-                if ((kpte_flags & _PAGE_PSE) == 0) { 
+                if (!pte_huge(*kpte)) {
                         set_pte(kpte, pfn_pte(pfn, prot));
                 } else {
                         /*
                          * split_large_page will take the reference for this
                          * change_page_attr on the split page.
                          */
-
                         struct page *split;
-                        ref_prot2 = __pgprot(pgprot_val(pte_pgprot(*lookup_address(address))) & ~(1<<_PAGE_BIT_PSE));
-
+                        ref_prot2 = pte_pgprot(pte_clrhuge(*kpte));
                         split = split_large_page(address, prot, ref_prot2);
                         if (!split)
                                 return -ENOMEM;
-                        set_pte(kpte,mk_pte(split, ref_prot2));
+                        set_pte(kpte, mk_pte(split, ref_prot2));
                         kpte_page = split;
-                }       
+                }
                 page_private(kpte_page)++;
-        } else if ((kpte_flags & _PAGE_PSE) == 0) { 
+        } else if (!pte_huge(*kpte)) {
                 set_pte(kpte, pfn_pte(pfn, ref_prot));
                 BUG_ON(page_private(kpte_page) == 0);
                 page_private(kpte_page)--;
diff --git a/include/asm-x86_64/pgtable.h b/include/asm-x86_64/pgtable.h
index f7614670c655..b34f43acdef1 100644
--- a/include/asm-x86_64/pgtable.h
+++ b/include/asm-x86_64/pgtable.h
@@ -283,6 +283,7 @@ static inline pte_t pte_mkdirty(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) |
 static inline pte_t pte_mkyoung(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); return pte; }
 static inline pte_t pte_mkwrite(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) | _PAGE_RW)); return pte; }
 static inline pte_t pte_mkhuge(pte_t pte)       { set_pte(&pte, __pte(pte_val(pte) | _PAGE_PSE)); return pte; }
+static inline pte_t pte_clrhuge(pte_t pte)      { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_PSE)); return pte; }
 
 struct vm_area_struct;