[PATCH] M68KNOMMU: user ARRAY_SIZE macro when appropriate

[sfrench/cifs-2.6.git] / mm / migrate.c

diff --git a/mm/migrate.c b/mm/migrate.c
index 20a8c2687b1efea5b7bb1ab23d6b9195a2e97453..e9b161bde95b4c382092a1c94a8fcfbd4bcf58f0 100644 (file)
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -294,7 +294,7 @@ out:
 static int migrate_page_move_mapping(struct address_space *mapping,
                struct page *newpage, struct page *page)
 {
-       struct page **radix_pointer;
+       void **pslot;
 
        if (!mapping) {
                /* Anonymous page */
@@ -305,12 +305,11 @@ static int migrate_page_move_mapping(struct address_space *mapping,
 
        write_lock_irq(&mapping->tree_lock);
 
-       radix_pointer = (struct page **)radix_tree_lookup_slot(
-                                               &mapping->page_tree,
-                                               page_index(page));
+       pslot = radix_tree_lookup_slot(&mapping->page_tree,
+                                       page_index(page));
 
        if (page_count(page) != 2 + !!PagePrivate(page) ||
-                       *radix_pointer != page) {
+                       (struct page *)radix_tree_deref_slot(pslot) != page) {
                write_unlock_irq(&mapping->tree_lock);
                return -EAGAIN;
        }
@@ -318,7 +317,7 @@ static int migrate_page_move_mapping(struct address_space *mapping,
        /*
         * Now we know that no one else is looking at the page.
         */
-       get_page(newpage);
+       get_page(newpage);      /* add cache reference */
 #ifdef CONFIG_SWAP
        if (PageSwapCache(page)) {
                SetPageSwapCache(newpage);
@@ -326,8 +325,14 @@ static int migrate_page_move_mapping(struct address_space *mapping,
        }
 #endif
 
-       *radix_pointer = newpage;
+       radix_tree_replace_slot(pslot, newpage);
+
+       /*
+        * Drop cache reference from old page.
+        * We know this isn't the last reference.
+        */
        __put_page(page);
+
        write_unlock_irq(&mapping->tree_lock);
 
        return 0;
@@ -409,6 +414,7 @@ int migrate_page(struct address_space *mapping,
 }
 EXPORT_SYMBOL(migrate_page);
 
+#ifdef CONFIG_BLOCK
 /*
  * Migration function for pages with buffers. This function can only be used
  * if the underlying filesystem guarantees that no other references to "page"
@@ -466,6 +472,7 @@ int buffer_migrate_page(struct address_space *mapping,
        return 0;
 }
 EXPORT_SYMBOL(buffer_migrate_page);
+#endif
 
 /*
  * Writeback a page to clean the dirty state
@@ -525,7 +532,7 @@ static int fallback_migrate_page(struct address_space *mapping,
         * Buffers may be managed in a filesystem specific way.
         * We must have no buffers or drop them.
         */
-       if (page_has_buffers(page) &&
+       if (PagePrivate(page) &&
            !try_to_release_page(page, GFP_KERNEL))
                return -EAGAIN;
 
@@ -950,7 +957,8 @@ asmlinkage long sys_move_pages(pid_t pid, unsigned long nr_pages,
                                goto out;
 
                        pm[i].node = node;
-               }
+               } else
+                       pm[i].node = 0; /* anything to not match MAX_NUMNODES */
        }
        /* End marker */
        pm[nr_pages].node = MAX_NUMNODES;