glusterd: Volume locks and transaction specific opinfos

With this patch we are replacing the existing cluster-wide
lock taken on glusterds across the cluster, with volume locks
which are also taken on glusterds across the cluster, but are
volume specific. So with the volume locks we are able to perform
more than one gluster operation at the same time, as long as the
operations are being performed on different volumes.

We maintain a global list of volume-locks (using a dict for a list)
where the key is the volume name, and which saves the uuid of the
originator glusterd. These locks are held and released per volume
transaction.

In order to acheive multiple gluster operations occuring at the
same time, we also separate opinfos in the op-state-machine, as a
part of this patch. To do so, we generate a unique transaction-id
(uuid) per gluster transaction. An opinfo is then associated with
this transaction id, which is used throughout the transaction. We
maintain a run-time global list(using a dict) of transaction-ids,
and their respective opinfos to achieve this.

Upstream Feature Page: http://www.gluster.org/community/documentation/index.php/Features/glusterd-volume-locks

Change-Id: Iaad505a854bac8de8f83beec0357eb6cde3f7ea8
BUG: 1011470
Signed-off-by: Avra Sengupta <asengupt@redhat.com>
Reviewed-on: http://review.gluster.org/5994
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/rpc/xdr/src/glusterd1-xdr.x b/rpc/xdr/src/glusterd1-xdr.x
index fc1bb58b4a8..f29a9d21458 100644
--- a/rpc/xdr/src/glusterd1-xdr.x
+++ b/rpc/xdr/src/glusterd1-xdr.x
@@ -125,3 +125,32 @@ struct gd1_mgmt_brick_op_rsp {
         opaque  output<>;
         string  op_errstr<>;
 } ;
+
+struct gd1_mgmt_volume_lock_req {
+        unsigned char  uuid[16];
+        unsigned char  txn_id[16];
+        int            op;
+        opaque         dict<>;
+}  ;
+
+struct gd1_mgmt_volume_lock_rsp {
+        unsigned char  uuid[16];
+        unsigned char  txn_id[16];
+        opaque         dict<>;
+        int            op_ret;
+        int            op_errno;
+}  ;
+
+struct gd1_mgmt_volume_unlock_req {
+        unsigned char  uuid[16];
+        unsigned char  txn_id[16];
+        opaque         dict<>;
+}  ;
+
+struct gd1_mgmt_volume_unlock_rsp {
+        unsigned char  uuid[16];
+        unsigned char  txn_id[16];
+        opaque         dict<>;
+        int            op_ret;
+        int            op_errno;
+}  ;