glusterd: op-version check for brickops.

cluster op-version must be atleast 4 for add/remove brick to proceed.
This change is required for the new afr-changelog xattr changes that
will be done for glusterFS 3.6 (http://review.gluster.org/#/c/7155/).

In add-brick, the check is done only when replica count is increased
because only that will affect the AFR xattrs.

In remove-brick, the check is unconditional failing which there will be
inconsistencies in the client xlator names amongst the volfiles of
different peers.

Change-Id: If981da2f33899aed585ab70bb11c09a093c9d8e6
BUG: 1066778
Signed-off-by: Ravishankar N <ravishankar@redhat.com>
Reviewed-on: http://review.gluster.org/7122
Reviewed-by: Kaushal M <kaushal@redhat.com>
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

4 files changed, 52 insertions, 4 deletions

diff --git a/libglusterfs/src/globals.h b/libglusterfs/src/globals.h
index 16ab962686f..2e520c10e02 100644
--- a/libglusterfs/src/globals.h
+++ b/libglusterfs/src/globals.h
@@ -33,6 +33,7 @@
                                 should keep changing with introduction of newer
                                 versions */
 #define GD_OP_VERSION_4    4 /* Op-Version 4 */
+#define GD_OP_VER_PERSISTENT_AFR_XATTRS GD_OP_VERSION_4
 
 #include "xlator.h"
 
diff --git a/xlators/mgmt/glusterd/src/glusterd-brick-ops.c b/xlators/mgmt/glusterd/src/glusterd-brick-ops.c
index f15ec7b18e7..1804dd02e9a 100644
--- a/xlators/mgmt/glusterd/src/glusterd-brick-ops.c
+++ b/xlators/mgmt/glusterd/src/glusterd-brick-ops.c
@@ -1207,6 +1207,7 @@ glusterd_op_stage_add_brick (dict_t *dict, char **op_errstr)
         int                                     ret = 0;
         char                                    *volname = NULL;
         int                                     count = 0;
+        int                                     replica_count = 0;
         int                                     i = 0;
         char                                    *bricks    = NULL;
         char                                    *brick_list = NULL;
@@ -1215,17 +1216,31 @@ glusterd_op_stage_add_brick (dict_t *dict, char **op_errstr)
         char                                    *brick = NULL;
         glusterd_brickinfo_t                    *brickinfo = NULL;
         glusterd_volinfo_t                      *volinfo = NULL;
-        glusterd_conf_t                         *priv = NULL;
+        xlator_t                                *this = NULL;
         char                                    msg[2048] = {0,};
         gf_boolean_t                            brick_alloc = _gf_false;
         char                                    *all_bricks = NULL;
         char                                    *str_ret = NULL;
         gf_boolean_t                            is_force = _gf_false;
 
-        priv = THIS->private;
-        if (!priv)
-                goto out;
+        this = THIS;
+        GF_ASSERT (this);
+
+        ret = dict_get_int32 (dict, "replica-count", &replica_count);
+        if (ret) {
+                gf_log (THIS->name, GF_LOG_ERROR,
+                        "Unable to get replica count");
+        }
 
+        if (replica_count > 0) {
+                ret = op_version_check (this, GD_OP_VER_PERSISTENT_AFR_XATTRS,
+                                        msg, sizeof(msg));
+                if (ret) {
+                        gf_log (this->name, GF_LOG_ERROR, "%s", msg);
+                        *op_errstr = gf_strdup (msg);
+                        goto out;
+                }
+        }
         ret = dict_get_str (dict, "volname", &volname);
         if (ret) {
                 gf_log (THIS->name, GF_LOG_ERROR,
@@ -1376,6 +1391,14 @@ glusterd_op_stage_remove_brick (dict_t *dict, char **op_errstr)
         this = THIS;
         GF_ASSERT (this);
 
+        ret = op_version_check (this, GD_OP_VER_PERSISTENT_AFR_XATTRS,
+                                msg, sizeof(msg));
+        if (ret) {
+                gf_log (this->name, GF_LOG_ERROR, "%s", msg);
+                *op_errstr = gf_strdup (msg);
+                goto out;
+        }
+
         ret = dict_get_str (dict, "volname", &volname);
         if (ret) {
                 gf_log (this->name, GF_LOG_ERROR, "Unable to get volume name");
diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.c b/xlators/mgmt/glusterd/src/glusterd-utils.c
index 0bec8c06ba8..fdfdcc28168 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.c
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.c
@@ -9042,6 +9042,27 @@ gd_update_volume_op_versions (glusterd_volinfo_t *volinfo)
         return;
 }
 
+int
+op_version_check (xlator_t *this, int min_op_version, char *msg, int msglen)
+{
+       int              ret  = 0;
+       glusterd_conf_t *priv = NULL;
+
+       GF_ASSERT (this);
+       GF_ASSERT (msg);
+
+       priv = this->private;
+       if (priv->op_version < min_op_version) {
+                snprintf (msg, msglen, "One or more nodes do not support "
+                          "the required op-version. Cluster op-version must "
+                          "atleast be %d.", min_op_version);
+                gf_log (this->name, GF_LOG_ERROR, "%s", msg);
+                ret = -1;
+      }
+      return ret;
+}
+
+
 /* A task is committed/completed once the task-id for it is cleared */
 gf_boolean_t
 gd_is_remove_brick_committed (glusterd_volinfo_t *volinfo)
diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.h b/xlators/mgmt/glusterd/src/glusterd-utils.h
index aebf5fcef05..ec59d914336 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.h
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.h
@@ -582,6 +582,9 @@ glusterd_is_same_address (char *name1, char *name2);
 void
 gd_update_volume_op_versions (glusterd_volinfo_t *volinfo);
 
+int
+op_version_check (xlator_t *this, int min_op_version, char *msg, int msglen);
+
 char*
 gd_peer_uuid_str (glusterd_peerinfo_t *peerinfo);