hugetlb: redefine hugepage copy functions

This patch modifies hugepage copy functions to have only destination
and source hugepages as arguments for later use.
The old ones are renamed from copy_{gigantic,huge}_page() to
copy_user_{gigantic,huge}_page().
This naming convention is consistent with that between copy_highpage()
and copy_user_highpage().

ChangeLog since v4:
- add blank line between local declaration and code
- remove unnecessary might_sleep()

ChangeLog since v2:
- change copy_huge_page() from macro to inline dummy function
  to avoid compile warning when !CONFIG_HUGETLB_PAGE.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 0b73c536afd2d3002c533d71457d792413d666e8..9e51f77d44ca9ec271752a554beaf59840263220 100644 (file)
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -44,6 +44,7 @@ int hugetlb_reserve_pages(struct inode *inode, long from, long to,
                                                int acctflags);
 void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed);
 void __isolate_hwpoisoned_huge_page(struct page *page);
+void copy_huge_page(struct page *dst, struct page *src);
 
 extern unsigned long hugepages_treat_as_movable;
 extern const unsigned long hugetlb_zero, hugetlb_infinity;
@@ -102,6 +103,9 @@ static inline void hugetlb_report_meminfo(struct seq_file *m)
 #define hugetlb_fault(mm, vma, addr, flags)    ({ BUG(); 0; })
 #define huge_pte_offset(mm, address)   0
 #define __isolate_hwpoisoned_huge_page(page)   0
+static inline void copy_huge_page(struct page *dst, struct page *src)
+{
+}
 
 #define hugetlb_change_protection(vma, address, end, newprot)
 

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 83fa0c3b6e2b14b5dc520cc58f607bf5c95c44ef..a73dbdcb89eb73ff838d4e5c737798f6a92f3487 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -423,14 +423,14 @@ static void clear_huge_page(struct page *page,
        }
 }
 
-static void copy_gigantic_page(struct page *dst, struct page *src,
+static void copy_user_gigantic_page(struct page *dst, struct page *src,
                           unsigned long addr, struct vm_area_struct *vma)
 {
        int i;
        struct hstate *h = hstate_vma(vma);
        struct page *dst_base = dst;
        struct page *src_base = src;
-       might_sleep();
+
        for (i = 0; i < pages_per_huge_page(h); ) {
                cond_resched();
                copy_user_highpage(dst, src, addr + i*PAGE_SIZE, vma);
@@ -440,14 +440,15 @@ static void copy_gigantic_page(struct page *dst, struct page *src,
                src = mem_map_next(src, src_base, i);
        }
 }
-static void copy_huge_page(struct page *dst, struct page *src,
+
+static void copy_user_huge_page(struct page *dst, struct page *src,
                           unsigned long addr, struct vm_area_struct *vma)
 {
        int i;
        struct hstate *h = hstate_vma(vma);
 
        if (unlikely(pages_per_huge_page(h) > MAX_ORDER_NR_PAGES)) {
-               copy_gigantic_page(dst, src, addr, vma);
+               copy_user_gigantic_page(dst, src, addr, vma);
                return;
        }
 
@@ -458,6 +459,40 @@ static void copy_huge_page(struct page *dst, struct page *src,
        }
 }
 
+static void copy_gigantic_page(struct page *dst, struct page *src)
+{
+       int i;
+       struct hstate *h = page_hstate(src);
+       struct page *dst_base = dst;
+       struct page *src_base = src;
+
+       for (i = 0; i < pages_per_huge_page(h); ) {
+               cond_resched();
+               copy_highpage(dst, src);
+
+               i++;
+               dst = mem_map_next(dst, dst_base, i);
+               src = mem_map_next(src, src_base, i);
+       }
+}
+
+void copy_huge_page(struct page *dst, struct page *src)
+{
+       int i;
+       struct hstate *h = page_hstate(src);
+
+       if (unlikely(pages_per_huge_page(h) > MAX_ORDER_NR_PAGES)) {
+               copy_gigantic_page(dst, src);
+               return;
+       }
+
+       might_sleep();
+       for (i = 0; i < pages_per_huge_page(h); i++) {
+               cond_resched();
+               copy_highpage(dst + i, src + i);
+       }
+}
+
 static void enqueue_huge_page(struct hstate *h, struct page *page)
 {
        int nid = page_to_nid(page);
@@ -2412,7 +2447,7 @@ retry_avoidcopy:
        if (unlikely(anon_vma_prepare(vma)))
                return VM_FAULT_OOM;
 
-       copy_huge_page(new_page, old_page, address, vma);
+       copy_user_huge_page(new_page, old_page, address, vma);
        __SetPageUptodate(new_page);
 
        /*