md/raid5: export is_congested test
the dm module will need this for dm-raid45.
Also only access ->queue->backing_dev_info->congested_fn
if ->queue actually exists. It won't in a dm target.
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index 61b6b25..d6470de 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -497,5 +497,7 @@
{
return layout >= 8 && layout <= 10;
}
+
+extern int md_raid5_congested(mddev_t *mddev, int bits);
extern int raid5_set_cache_size(mddev_t *mddev, int size);
#endif
