FS-Cache: Don't delete pending pages from the page-store tracking tree

Don't delete pending pages from the page-store tracking tree, but rather send
them for another write as they've presumably been updated.
Signed-off-by: David Howells <dhowells@redhat.com>

fs/fscache/page.c

@@ -57,8 +57,11 @@ static void fscache_end_page_write(struct fscache_object *object,
 		/* delete the page from the tree if it is now no longer
 		 * pending */
 		spin_lock(&cookie->stores_lock);
-		fscache_stat(&fscache_n_store_radix_deletes);
-		xpage = radix_tree_delete(&cookie->stores, page->index);
+		if (!radix_tree_tag_get(&cookie->stores, page->index,
+					FSCACHE_COOKIE_PENDING_TAG)) {
+			fscache_stat(&fscache_n_store_radix_deletes);
+			xpage = radix_tree_delete(&cookie->stores, page->index);
+		}
 		spin_unlock(&cookie->stores_lock);
 		wake_up_bit(&cookie->flags, 0);
 	}

lib/radix-tree.c

@@ -546,7 +546,6 @@ out:
 }
 EXPORT_SYMBOL(radix_tree_tag_clear);
 
-#ifndef __KERNEL__	/* Only the test harness uses this at present */
 /**
  * radix_tree_tag_get - get a tag on a radix tree node
  * @root:		radix tree root
@@ -609,7 +608,6 @@ int radix_tree_tag_get(struct radix_tree_root *root,
 	}
 }
 EXPORT_SYMBOL(radix_tree_tag_get);
-#endif
 
 /**
  *	radix_tree_next_hole    -    find the next hole (not-present entry)