ceph: drop src address(es) from message header [new protocol feature]

The CEPH_FEATURE_NOSRCADDR protocol feature avoids putting the full source
address in each message header (twice).  This patch switches the client to
the new scheme, and _requires_ this feature on the server.  The server
will support both the old and new schemes.  That means an old client will
work with a new server, but a new client will not work with an old server.

Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 19 insertions, 1 deletions

diff --git a/fs/ceph/msgr.h b/fs/ceph/msgr.h
index 8aaab414f3f8..6baa8e4f8e7f 100644
--- a/fs/ceph/msgr.h
+++ b/fs/ceph/msgr.h
@@ -120,7 +120,7 @@ struct ceph_msg_connect_reply {
 /*
  * message header
  */
-struct ceph_msg_header {
+struct ceph_msg_header_old {
         __le64 seq;       /* message seq# for this session */
         __le64 tid;       /* transaction id */
         __le16 type;      /* message type */
@@ -138,6 +138,24 @@ struct ceph_msg_header {
         __le32 crc;       /* header crc32c */
 } __attribute__ ((packed));
 
+struct ceph_msg_header {
+        __le64 seq;       /* message seq# for this session */
+        __le64 tid;       /* transaction id */
+        __le16 type;      /* message type */
+        __le16 priority;  /* priority.  higher value == higher priority */
+        __le16 version;   /* version of message encoding */
+
+        __le32 front_len; /* bytes in main payload */
+        __le32 middle_len;/* bytes in middle payload */
+        __le32 data_len;  /* bytes of data payload */
+        __le16 data_off;  /* sender: include full offset;
+                             receiver: mask against ~PAGE_MASK */
+
+        struct ceph_entity_name src;
+        __le32 reserved;
+        __le32 crc;       /* header crc32c */
+} __attribute__ ((packed));
+
 #define CEPH_MSG_PRIO_LOW     64
 #define CEPH_MSG_PRIO_DEFAULT 127
 #define CEPH_MSG_PRIO_HIGH    196