[PATCH] hugepage: Small fixes to hugepage clear/copy path
[linux-2.6.git] / mm / hugetlb.c
index 783098f..41b1038 100644 (file)
@@ -27,6 +27,29 @@ static struct list_head hugepage_freelists[MAX_NUMNODES];
 static unsigned int nr_huge_pages_node[MAX_NUMNODES];
 static unsigned int free_huge_pages_node[MAX_NUMNODES];
 
+static void clear_huge_page(struct page *page, unsigned long addr)
+{
+       int i;
+
+       might_sleep();
+       for (i = 0; i < (HPAGE_SIZE/PAGE_SIZE); i++) {
+               cond_resched();
+               clear_user_highpage(page + i, addr);
+       }
+}
+
+static void copy_huge_page(struct page *dst, struct page *src,
+                          unsigned long addr)
+{
+       int i;
+
+       might_sleep();
+       for (i = 0; i < HPAGE_SIZE/PAGE_SIZE; i++) {
+               cond_resched();
+               copy_user_highpage(dst + i, src + i, addr + i*PAGE_SIZE);
+       }
+}
+
 /*
  * Protects updates to hugepage_freelists, nr_huge_pages, and free_huge_pages
  */
@@ -98,7 +121,6 @@ void free_huge_page(struct page *page)
 struct page *alloc_huge_page(struct vm_area_struct *vma, unsigned long addr)
 {
        struct page *page;
-       int i;
 
        spin_lock(&hugetlb_lock);
        page = dequeue_huge_page(vma, addr);
@@ -108,8 +130,6 @@ struct page *alloc_huge_page(struct vm_area_struct *vma, unsigned long addr)
        }
        spin_unlock(&hugetlb_lock);
        set_page_refcounted(page);
-       for (i = 0; i < (HPAGE_SIZE/PAGE_SIZE); ++i)
-               clear_user_highpage(&page[i], addr);
        return page;
 }
 
@@ -367,7 +387,7 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
                        unsigned long address, pte_t *ptep, pte_t pte)
 {
        struct page *old_page, *new_page;
-       int i, avoidcopy;
+       int avoidcopy;
 
        old_page = pte_page(pte);
 
@@ -388,9 +408,7 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
        }
 
        spin_unlock(&mm->page_table_lock);
-       for (i = 0; i < HPAGE_SIZE/PAGE_SIZE; i++)
-               copy_user_highpage(new_page + i, old_page + i,
-                                  address + i*PAGE_SIZE);
+       copy_huge_page(new_page, old_page, address);
        spin_lock(&mm->page_table_lock);
 
        ptep = huge_pte_offset(mm, address & HPAGE_MASK);
@@ -435,6 +453,7 @@ retry:
                        ret = VM_FAULT_OOM;
                        goto out;
                }
+               clear_huge_page(page, address);
 
                if (vma->vm_flags & VM_SHARED) {
                        int err;