diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 24327adc925ce97870a7fc33defe3853806ee9aa..44ee489f4a6e4ca19d9010956170e092860c94bd 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -959,7 +959,7 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result)
 		 * table reload).
 		 */
 		if (!free_blocks) {
-			DMWARN("%s: no free space available.",
+			DMWARN("%s: no free data space available.",
 			       dm_device_name(pool->pool_md));
 			spin_lock_irqsave(&pool->lock, flags);
 			pool->no_free_space = 1;
@@ -969,8 +969,16 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result)
 	}
 
 	r = dm_pool_alloc_data_block(pool->pmd, result);
-	if (r)
+	if (r) {
+		if (r == -ENOSPC &&
+		    !dm_pool_get_free_metadata_block_count(pool->pmd, &free_blocks) &&
+		    !free_blocks) {
+			DMWARN("%s: no free metadata space available.",
+			       dm_device_name(pool->pool_md));
+			set_pool_mode(pool, PM_READ_ONLY);
+		}
 		return r;
+	}
 
 	return 0;
 }