SetPageUptodate(page);
 
        if (startio) {
-               if (count)
-                       wbc->nr_to_write--;
+               if (count) {
+                       struct backing_dev_info *bdi;
+
+                       bdi = inode->i_mapping->backing_dev_info;
+                       if (bdi_write_congested(bdi)) {
+                               wbc->encountered_congestion = 1;
+                               done = 1;
+                       } else if (--wbc->nr_to_write <= 0) {
+                               done = 1;
+                       }
+               }
                xfs_start_page_writeback(page, wbc, !page_dirty, count);
        }
 
        int                     all_bh = unmapped;
 
        /* wait for other IO threads? */
-       if (startio && wbc->sync_mode != WB_SYNC_NONE)
+       if (startio && (wbc->sync_mode == WB_SYNC_NONE && wbc->nonblocking))
                trylock_flag |= BMAPI_TRYLOCK;
 
        /* Is this page beyond the end of the file? */