drbd: Introduce protocol version 100 headers

The 8 byte header finally becomes too small. With the protocol 100 header we
have 16 bit for the volume number, proper 32 bit for the data length, and
32 bit for further extensions in the future.

Previous versions of drbd are using version 80 headers for all packets
short enough for protocol 80.  They support both header versions in
worker context, but only version 80 headers in asynchronous context.
For backwards compatibility, continue to use version 80 headers for
short packets before protocol version 100.

From protocol version 100 on, use the same header version for all
packets.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This commit is contained in:
Andreas Gruenbacher 2011-03-30 16:00:17 +02:00 committed by Philipp Reisner
parent e658983af6
commit 0c8e36d9b8
7 changed files with 50 additions and 12 deletions

View file

@ -95,8 +95,6 @@ GENL_struct(DRBD_NLA_CFG_REPLY, 1, drbd_cfg_reply,
* and/or the replication group (aka resource) name,
* and the volume id within the resource. */
GENL_struct(DRBD_NLA_CFG_CONTEXT, 2, drbd_cfg_context,
/* currently only 256 volumes per group,
* but maybe we still change that */
__u32_field(1, GENLA_F_MANDATORY, ctx_volume)
__str_field(2, GENLA_F_MANDATORY, ctx_conn_name, 128)
)