dm bufio: prefetch
This patch introduces a new function dm_bufio_prefetch. It prefetches
the specified range of blocks into dm-bufio cache without waiting
for i/o completion.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-bufio.h b/drivers/md/dm-bufio.h
index 5c4c3a0..b142946 100644
--- a/drivers/md/dm-bufio.h
+++ b/drivers/md/dm-bufio.h
@@ -63,6 +63,14 @@
struct dm_buffer **bp);
/*
+ * Prefetch the specified blocks to the cache.
+ * The function starts to read the blocks and returns without waiting for
+ * I/O to finish.
+ */
+void dm_bufio_prefetch(struct dm_bufio_client *c,
+ sector_t block, unsigned n_blocks);
+
+/*
* Release a reference obtained with dm_bufio_{read,get,new}. The data
* pointer and dm_buffer pointer is no longer valid after this call.
*/