int dm_bm_unlock(struct dm_block *b);
-/*
- * An optimisation; we often want to copy a block's contents to a new
- * block. eg, as part of the shadowing operation. It's far better for
- * bufio to do this move behind the scenes than hold 2 locks and memcpy the
- * data.
- */
-int dm_bm_unlock_move(struct dm_block *b, dm_block_t n);
-
/*
* It's a common idiom to have a superblock that should be committed last.
*
int dm_bm_flush_and_unlock(struct dm_block_manager *bm,
struct dm_block *superblock);
+/*
+ * Switches the bm to a read only mode. Once read-only mode
+ * has been entered the following functions will return -EPERM.
+ *
+ * dm_bm_write_lock
+ * dm_bm_write_lock_zero
+ * dm_bm_flush_and_unlock
+ *
+ * Additionally you should not use dm_bm_unlock_move, however no error will
+ * be returned if you do.
+ */
+void dm_bm_set_read_only(struct dm_block_manager *bm);
+
u32 dm_bm_checksum(const void *data, size_t len, u32 init_xor);
/*----------------------------------------------------------------*/