1 files changed, 33 insertions, 0 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index f173c5af6461..cdee391fc7bf 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1257,6 +1257,39 @@ int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
                                 GFP_NOFS);
 }
 
+int extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end)
+{
+        unsigned long index = start >> PAGE_CACHE_SHIFT;
+        unsigned long end_index = end >> PAGE_CACHE_SHIFT;
+        struct page *page;
+
+        while (index <= end_index) {
+                page = find_get_page(inode->i_mapping, index);
+                BUG_ON(!page); /* Pages should be in the extent_io_tree */
+                clear_page_dirty_for_io(page);
+                page_cache_release(page);
+                index++;
+        }
+        return 0;
+}
+
+int extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end)
+{
+        unsigned long index = start >> PAGE_CACHE_SHIFT;
+        unsigned long end_index = end >> PAGE_CACHE_SHIFT;
+        struct page *page;
+
+        while (index <= end_index) {
+                page = find_get_page(inode->i_mapping, index);
+                BUG_ON(!page); /* Pages should be in the extent_io_tree */
+                account_page_redirty(page);
+                __set_page_dirty_nobuffers(page);
+                page_cache_release(page);
+                index++;
+        }
+        return 0;
+}
+
 /*
  * helper function to set both pages and extents in the tree writeback
  */