1 files changed, 14 insertions, 1 deletions

diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c
index ba91b408abad..d84566496746 100644
--- a/drivers/block/drbd/drbd_bitmap.c
+++ b/drivers/block/drbd/drbd_bitmap.c
@@ -889,6 +889,7 @@ struct bm_aio_ctx {
         unsigned int done;
         unsigned flags;
 #define BM_AIO_COPY_PAGES       1
+#define BM_WRITE_ALL_PAGES      2
         int error;
         struct kref kref;
 };
@@ -1059,7 +1060,8 @@ static int bm_rw(struct drbd_conf *mdev, int rw, unsigned flags, unsigned lazy_w
                 if (lazy_writeout_upper_idx && i == lazy_writeout_upper_idx)
                         break;
                 if (rw & WRITE) {
-                        if (bm_test_page_unchanged(b->bm_pages[i])) {
+                        if (!(flags & BM_WRITE_ALL_PAGES) &&
+                            bm_test_page_unchanged(b->bm_pages[i])) {
                                 dynamic_dev_dbg(DEV, "skipped bm write for idx %u\n", i);
                                 continue;
                         }
@@ -1141,6 +1143,17 @@ int drbd_bm_write(struct drbd_conf *mdev) __must_hold(local)
 }
 
 /**
+ * drbd_bm_write_all() - Write the whole bitmap to its on disk location.
+ * @mdev:       DRBD device.
+ *
+ * Will write all pages.
+ */
+int drbd_bm_write_all(struct drbd_conf *mdev) __must_hold(local)
+{
+        return bm_rw(mdev, WRITE, BM_WRITE_ALL_PAGES, 0);
+}
+
+/**
  * drbd_bm_lazy_write_out() - Write bitmap pages 0 to @upper_idx-1, if they have changed.
  * @mdev:       DRBD device.
  * @upper_idx:  0: write all changed pages; +ve: page index to stop scanning for changed pages