glusterd,glusterfsd,libgfapi: Client op-version

This patch introduces op-version support for glusterfs clients.
Now, a client sends its supported op-versions during the volfile fetch request
and glusterd will return the volfile only if the client can support the current
op-version of the cluster.

Change-Id: Iab1f1f1706802962bcf27058657c44e8a344d2f6
BUG: 907311
Signed-off-by: Kaushal M <kaushal@redhat.com>
Reviewed-on: http://review.gluster.org/4247
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Amar Tumballi <amarts@redhat.com>
Reviewed-by: Anand Avati <avati@redhat.com>

2 files changed, 69 insertions, 20 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-handshake.c b/xlators/mgmt/glusterd/src/glusterd-handshake.c
index 6a273df5..5b3299d5 100644
--- a/xlators/mgmt/glusterd/src/glusterd-handshake.c
+++ b/xlators/mgmt/glusterd/src/glusterd-handshake.c
@@ -124,7 +124,17 @@ server_getspec (rpcsvc_request_t *req)
         gf_getspec_req        args                   = {0,};
         gf_getspec_rsp        rsp                    = {0,};
         char                  addrstr[RPCSVC_PEER_STRLEN] = {0};
+        dict_t               *dict                   = NULL;
+        xlator_t             *this                   = NULL;
+        glusterd_conf_t      *conf                   = NULL;
+        int                   client_min_op_version  = 0;
+        int                   client_max_op_version  = 0;
 
+        this = THIS;
+        GF_ASSERT (this);
+
+        conf = this->private;
+        GF_ASSERT (conf);
 
         ret = xdr_to_generic (req->msg[0], &args,
                               (xdrproc_t)xdr_gf_getspec_req);
@@ -134,6 +144,63 @@ server_getspec (rpcsvc_request_t *req)
                 goto fail;
         }
 
+        if (!args.xdata.xdata_len) {
+                // For clients <= 3.3.0, only allow if op_version = 1
+                if (1 != conf->op_version) {
+                        ret = -1;
+                        op_errno = ENOTSUP;
+                        gf_log (this->name, GF_LOG_INFO,
+                                "Client %s doesn't support required op-version. "
+                                "Rejecting getspec request.",
+                                req->trans->peerinfo.identifier);
+                        goto fail;
+                }
+        } else {
+                // For clients > 3.3, only allow if they can support
+                // clusters' op_version
+                dict = dict_new ();
+                if (!dict) {
+                        ret = -1;
+                        goto fail;
+                }
+
+                ret = dict_unserialize (args.xdata.xdata_val,
+                                        args.xdata.xdata_len, &dict);
+                if (ret) {
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "Failed to unserialize request dictionary");
+                        goto fail;
+                }
+
+                ret = dict_get_int32 (dict, "min-op-version",
+                                      &client_min_op_version);
+                if (ret) {
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "Failed to get client-min-op-version");
+                        goto fail;
+                }
+
+                ret = dict_get_int32 (dict, "max-op-version",
+                                      &client_max_op_version);
+                if (ret) {
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "Failed to get client-max-op-version");
+                        goto fail;
+                }
+
+                if ((client_min_op_version > conf->op_version) ||
+                    (client_max_op_version < conf->op_version)) {
+                        ret = -1;
+                        op_errno = ENOTSUP;
+                        //TODO: Add client identifier
+                        gf_log (this->name, GF_LOG_INFO,
+                                "Client %s doesn't support required op-version. "
+                                "Rejecting getspec request.",
+                                req->trans->peerinfo.identifier);
+                        goto fail;
+                }
+        }
+
         volume = args.key;
 
         trans = req->trans;
@@ -387,7 +454,7 @@ glusterd_mgmt_hndsk_versions_ack (rpcsvc_request_t *req)
         glusterd_conf_t   *conf            = NULL;
         int                ret             = -1;
         int                op_errno        = EINVAL;
-        int32_t            peer_op_version = 0;
+        int                peer_op_version = 0;
         gf_mgmt_hndsk_req  args            = {{0,},};
         gf_mgmt_hndsk_rsp  rsp             = {0,};
 
@@ -406,8 +473,7 @@ glusterd_mgmt_hndsk_versions_ack (rpcsvc_request_t *req)
                                       (args.hndsk.hndsk_len), ret, op_errno,
                                       out);
 
-        ret = dict_get_int32 (clnt_dict, GD_OP_VERSION_KEY,
-                              &peer_op_version);
+        ret = dict_get_int32 (clnt_dict, GD_OP_VERSION_KEY, &peer_op_version);
         if (ret) {
                 gf_log (this->name, GF_LOG_WARNING,
                         "failed to get the op-version key peer=%s",
diff --git a/xlators/mgmt/glusterd/src/glusterd.h b/xlators/mgmt/glusterd/src/glusterd.h
index f7bfad69..95e23674 100644
--- a/xlators/mgmt/glusterd/src/glusterd.h
+++ b/xlators/mgmt/glusterd/src/glusterd.h
@@ -114,23 +114,6 @@ typedef struct {
         gf_boolean_t            online;
 } nodesrv_t;
 
-#define GD_OP_VERSION_KEY     "operating-version"
-#define GD_MIN_OP_VERSION_KEY "minimum-operating-version"
-#define GD_MAX_OP_VERSION_KEY "maxium-operating-version"
-
-/* Gluster versions - OP-VERSION mapping
- *
- * 3.3.0                - 1
- * 3.3.Next/3.Next      - 2
- *
- * (TODO: Change above comment once gluster version is finalised)
- */
-#define GD_OP_VERSION_MIN  1 /* MIN is the fresh start op-version, mostly
-                                should not change */
-#define GD_OP_VERSION_MAX  2 /* MAX VERSION is the maximum count in VME table,
-                                should keep changing with introduction of newer
-                                versions */
-
 typedef struct {
         gf_boolean_t    quorum;
         double          quorum_ratio;