commit a19308048182d5f9e16b03b1d1c038d9346c7589
author Alex Elder <elder@inktank.com> Thu Mar 14 14:09:06 2013 -0500
committer Sage Weil <sage@inktank.com> Wed May 01 21:17:57 2013 -0700
tree 1395d1027753afa2ab5caec1808385f3a68893be
parent fdce58ccb5df621695b079378c619046acabc778

libceph: record message data length

Keep track of the length of the data portion for a message in a
separate field in the ceph_msg structure.  This information has
been maintained in wire byte order in the message header, but
that's going to change soon.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

net/ceph/messenger.c

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index ee16086..fa9b4d0 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -2981,6 +2981,7 @@
 
 	BUG_ON(!pages);
 	BUG_ON(!length);
+	BUG_ON(msg->data_length);
 	BUG_ON(msg->data != NULL);
 
 	data = ceph_msg_data_create(CEPH_MSG_DATA_PAGES);
@@ -2990,6 +2991,7 @@
 	data->alignment = alignment & ~PAGE_MASK;
 
 	msg->data = data;
+	msg->data_length = length;
 }
 EXPORT_SYMBOL(ceph_msg_data_set_pages);
 
@@ -3000,6 +3002,7 @@
 
 	BUG_ON(!pagelist);
 	BUG_ON(!pagelist->length);
+	BUG_ON(msg->data_length);
 	BUG_ON(msg->data != NULL);
 
 	data = ceph_msg_data_create(CEPH_MSG_DATA_PAGELIST);
@@ -3007,14 +3010,17 @@
 	data->pagelist = pagelist;
 
 	msg->data = data;
+	msg->data_length = pagelist->length;
 }
 EXPORT_SYMBOL(ceph_msg_data_set_pagelist);
 
-void ceph_msg_data_set_bio(struct ceph_msg *msg, struct bio *bio)
+void ceph_msg_data_set_bio(struct ceph_msg *msg, struct bio *bio,
+		size_t length)
 {
 	struct ceph_msg_data *data;
 
 	BUG_ON(!bio);
+	BUG_ON(msg->data_length);
 	BUG_ON(msg->data != NULL);
 
 	data = ceph_msg_data_create(CEPH_MSG_DATA_BIO);
@@ -3022,6 +3028,7 @@
 	data->bio = bio;
 
 	msg->data = data;
+	msg->data_length = length;
 }
 EXPORT_SYMBOL(ceph_msg_data_set_bio);
 
@@ -3200,6 +3207,7 @@
 	}
 	ceph_msg_data_destroy(m->data);
 	m->data = NULL;
+	m->data_length = 0;
 
 	if (m->pool)
 		ceph_msgpool_put(m->pool, m);