1 files changed, 21 insertions, 2 deletions

diff --git a/mm/swapfile.c b/mm/swapfile.c
index f89af5ba2eb2..6ffc87602f4a 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1329,6 +1329,14 @@ static void destroy_swap_extents(struct swap_info_struct *sis)
                 list_del(&se->list);
                 kfree(se);
         }
+
+        if (sis->flags & SWP_FILE) {
+                struct file *swap_file = sis->swap_file;
+                struct address_space *mapping = swap_file->f_mapping;
+
+                sis->flags &= ~SWP_FILE;
+                mapping->a_ops->swap_deactivate(swap_file);
+        }
 }
 
 /*
@@ -1410,7 +1418,9 @@ add_swap_extent(struct swap_info_struct *sis, unsigned long start_page,
  */
 static int setup_swap_extents(struct swap_info_struct *sis, sector_t *span)
 {
-        struct inode *inode;
+        struct file *swap_file = sis->swap_file;
+        struct address_space *mapping = swap_file->f_mapping;
+        struct inode *inode = mapping->host;
         unsigned blocks_per_page;
         unsigned long page_no;
         unsigned blkbits;
@@ -1421,13 +1431,22 @@ static int setup_swap_extents(struct swap_info_struct *sis, sector_t *span)
         int nr_extents = 0;
         int ret;
 
-        inode = sis->swap_file->f_mapping->host;
         if (S_ISBLK(inode->i_mode)) {
                 ret = add_swap_extent(sis, 0, sis->max, 0);
                 *span = sis->pages;
                 goto out;
         }
 
+        if (mapping->a_ops->swap_activate) {
+                ret = mapping->a_ops->swap_activate(swap_file);
+                if (!ret) {
+                        sis->flags |= SWP_FILE;
+                        ret = add_swap_extent(sis, 0, sis->max, 0);
+                        *span = sis->pages;
+                }
+                goto out;
+        }
+
         blkbits = inode->i_blkbits;
         blocks_per_page = PAGE_SIZE >> blkbits;