ceph: messenger and osdc changes for rbd

Allow the messenger to send/receive data in a bio.  This is added
so that we wouldn't need to copy the data into pages or some other buffer
when doing IO for an rbd block device.

We can now have trailing variable sized data for osd
ops.  Also osd ops encoding is more modular.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 4 insertions, 0 deletions

diff --git a/fs/ceph/messenger.h b/fs/ceph/messenger.h
index 76fbc957bc13..5a79450604ef 100644
--- a/fs/ceph/messenger.h
+++ b/fs/ceph/messenger.h
@@ -82,6 +82,10 @@ struct ceph_msg {
         struct ceph_pagelist *pagelist; /* instead of pages */
         struct list_head list_head;
         struct kref kref;
+        struct bio  *bio;               /* instead of pages/pagelist */
+        struct bio  *bio_iter;          /* bio iterator */
+        int bio_seg;                    /* current bio segment */
+        struct ceph_pagelist *trail;    /* the trailing part of the data */
         bool front_is_vmalloc;
         bool more_to_follow;
         bool needs_out_seq;