[PATCH] Swap Migration V5: Add CONFIG_MIGRATION for page migration support

[powerpc.git] / mm / rmap.c

diff --git a/mm/rmap.c b/mm/rmap.c
index 491ac35..6f3f7db 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -434,6 +434,30 @@ int page_referenced(struct page *page, int is_locked)
        return referenced;
 }
 
+/**
+ * page_set_anon_rmap - setup new anonymous rmap
+ * @page:      the page to add the mapping to
+ * @vma:       the vm area in which the mapping is added
+ * @address:   the user virtual address mapped
+ */
+static void __page_set_anon_rmap(struct page *page,
+       struct vm_area_struct *vma, unsigned long address)
+{
+       struct anon_vma *anon_vma = vma->anon_vma;
+
+       BUG_ON(!anon_vma);
+       anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON;
+       page->mapping = (struct address_space *) anon_vma;
+
+       page->index = linear_page_index(vma, address);
+
+       /*
+        * nr_mapped state can be updated without turning off
+        * interrupts because it is not modified via interrupt.
+        */
+       __inc_page_state(nr_mapped);
+}
+
 /**
  * page_add_anon_rmap - add pte mapping to an anonymous page
  * @page:      the page to add the mapping to
@@ -445,20 +469,27 @@ int page_referenced(struct page *page, int is_locked)
 void page_add_anon_rmap(struct page *page,
        struct vm_area_struct *vma, unsigned long address)
 {
-       if (atomic_inc_and_test(&page->_mapcount)) {
-               struct anon_vma *anon_vma = vma->anon_vma;
-
-               BUG_ON(!anon_vma);
-               anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON;
-               page->mapping = (struct address_space *) anon_vma;
-
-               page->index = linear_page_index(vma, address);
-
-               inc_page_state(nr_mapped);
-       }
+       if (atomic_inc_and_test(&page->_mapcount))
+               __page_set_anon_rmap(page, vma, address);
        /* else checking page index and mapping is racy */
 }
 
+/*
+ * page_add_new_anon_rmap - add pte mapping to a new anonymous page
+ * @page:      the page to add the mapping to
+ * @vma:       the vm area in which the mapping is added
+ * @address:   the user virtual address mapped
+ *
+ * Same as page_add_anon_rmap but must only be called on *new* pages.
+ * This means the inc-and-test can be bypassed.
+ */
+void page_add_new_anon_rmap(struct page *page,
+       struct vm_area_struct *vma, unsigned long address)
+{
+       atomic_set(&page->_mapcount, 0); /* elevate count by 1 (starts at -1) */
+       __page_set_anon_rmap(page, vma, address);
+}
+
 /**
  * page_add_file_rmap - add pte mapping to a file page
  * @page: the page to add the mapping to
@@ -471,7 +502,7 @@ void page_add_file_rmap(struct page *page)
        BUG_ON(!pfn_valid(page_to_pfn(page)));
 
        if (atomic_inc_and_test(&page->_mapcount))
-               inc_page_state(nr_mapped);
+               __inc_page_state(nr_mapped);
 }
 
 /**
@@ -495,7 +526,7 @@ void page_remove_rmap(struct page *page)
                 */
                if (page_test_and_clear_dirty(page))
                        set_page_dirty(page);
-               dec_page_state(nr_mapped);
+               __dec_page_state(nr_mapped);
        }
 }
 
@@ -641,7 +672,7 @@ static void try_to_unmap_cluster(unsigned long cursor,
                        continue;
 
                /* Nuke the page table entry. */
-               flush_cache_page(vma, address, pfn);
+               flush_cache_page(vma, address, pte_pfn(*pte));
                pteval = ptep_clear_flush(vma, address, pte);
 
                /* If nonlinear, store the file page offset in the pte. */