dm snapshot: use dm-bufio

Use dm-bufio for initial loading of the exceptions.
Introduce a new function dm_bufio_forget that frees the given buffer.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/md/dm-bufio.h b/drivers/md/dm-bufio.h
index b142946a9e32..3dac37627ba4 100644
--- a/drivers/md/dm-bufio.h
+++ b/drivers/md/dm-bufio.h
@@ -108,6 +108,13 @@ int dm_bufio_issue_flush(struct dm_bufio_client *c);
  */
 void dm_bufio_release_move(struct dm_buffer *b, sector_t new_block);
 
+/*
+ * Free the given buffer.
+ * This is just a hint, if the buffer is in use or dirty, this function
+ * does nothing.
+ */
+void dm_bufio_forget(struct dm_bufio_client *c, sector_t block);
+
 unsigned dm_bufio_get_block_size(struct dm_bufio_client *c);
 sector_t dm_bufio_get_device_size(struct dm_bufio_client *c);
 sector_t dm_bufio_get_block_number(struct dm_buffer *b);