libceph: implement bio message data item cursor
Implement and use cursor routines for bio message data items for
outbound message data.
(See the previous commit for reasoning in support of the changes
in out_msg_pos_next().)
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
diff --git a/include/linux/ceph/messenger.h b/include/linux/ceph/messenger.h
index 716c3fd..76b4645 100644
--- a/include/linux/ceph/messenger.h
+++ b/include/linux/ceph/messenger.h
@@ -98,6 +98,13 @@
struct ceph_msg_data_cursor {
bool last_piece; /* now at last piece of data item */
union {
+#ifdef CONFIG_BLOCK
+ struct { /* bio */
+ struct bio *bio; /* bio from list */
+ unsigned int vector_index; /* vector from bio */
+ unsigned int vector_offset; /* bytes from vector */
+ };
+#endif /* CONFIG_BLOCK */
struct { /* pagelist */
struct page *page; /* page from list */
size_t offset; /* bytes from list */