glusterd: quorum validatation in glusterd syncop framework

Previously glusterd was not checking quorum validation in syncop framework.
So when there is loss in quorum then few operation (for eg. add-brick,
remove-brick, volume set) which is based on syncop framework passed
successfully with out doing quorum validation check.

With this change it will do quorum validation in syncop framework and it will
block all operation (except volume set <quorum options> and "volume reset all"
commands) when there is loss in quorum.

Change-Id: I4c2ef16728d55c98a228bb86795023d9c1f4e9fb
BUG: 1177132
Signed-off-by: Gaurav Kumar Garg <ggarg@redhat.com>
Reviewed-on: http://review.gluster.org/9349
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Atin Mukherjee <amukherj@redhat.com>
Reviewed-by: Krishnan Parthasarathi <kparthas@redhat.com>
Tested-by: Krishnan Parthasarathi <kparthas@redhat.com>

1 files changed, 101 insertions, 0 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.c b/xlators/mgmt/glusterd/src/glusterd-utils.c
index d829676228c..5c2d6f23309 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.c
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.c
@@ -1096,6 +1096,107 @@ out:
 }
 #endif
 
+gf_boolean_t
+glusterd_is_get_op (xlator_t *this, glusterd_op_t op, dict_t *dict)
+{
+        char            *key = NULL;
+        char            *volname = NULL;
+        int             ret = 0;
+
+        if (op == GD_OP_STATUS_VOLUME)
+                return _gf_true;
+
+        if (op == GD_OP_SET_VOLUME) {
+                /*check for set volume help*/
+                ret = dict_get_str (dict, "volname", &volname);
+                if (volname &&
+                    ((strcmp (volname, "help") == 0) ||
+                     (strcmp (volname, "help-xml") == 0))) {
+                        ret = dict_get_str (dict, "key1", &key);
+                        if (ret < 0)
+                                return _gf_true;
+                }
+        }
+        return _gf_false;
+}
+
+gf_boolean_t
+glusterd_is_quorum_validation_required (xlator_t *this, glusterd_op_t op,
+                                        dict_t *dict)
+{
+        gf_boolean_t    required = _gf_true;
+        char            *key = NULL;
+        char            *key_fixed = NULL;
+        int             ret = -1;
+
+        if (glusterd_is_get_op (this, op, dict)) {
+                required = _gf_false;
+                goto out;
+        }
+        if ((op != GD_OP_SET_VOLUME) && (op != GD_OP_RESET_VOLUME))
+                goto out;
+        if (op == GD_OP_SET_VOLUME)
+                ret = dict_get_str (dict, "key1", &key);
+        else if (op == GD_OP_RESET_VOLUME)
+                ret = dict_get_str (dict, "key", &key);
+        if (ret)
+                goto out;
+        ret = glusterd_check_option_exists (key, &key_fixed);
+        if (ret <= 0)
+                goto out;
+        if (key_fixed)
+                key = key_fixed;
+        if (glusterd_is_quorum_option (key))
+                required = _gf_false;
+out:
+        GF_FREE (key_fixed);
+        return required;
+}
+
+/* This function should not be used when the quorum validation needs to happen
+ * on non-global peer list */
+int
+glusterd_validate_quorum (xlator_t *this, glusterd_op_t op,
+                             dict_t *dict, char **op_errstr)
+{
+        int                      ret     = 0;
+        char                    *volname = NULL;
+        glusterd_volinfo_t      *volinfo = NULL;
+        char                    *errstr  = NULL;
+
+        errstr = "Quorum not met. Volume operation not allowed.";
+        if (!glusterd_is_quorum_validation_required (this, op, dict))
+                goto out;
+
+        ret = dict_get_str (dict, "volname", &volname);
+        if (ret) {
+                ret = 0;
+                goto out;
+        }
+
+        ret = glusterd_volinfo_find (volname, &volinfo);
+        if (ret) {
+                ret = 0;
+                goto out;
+        }
+
+        /* Passing NULL implies quorum calculation will happen on global peer
+         * list */
+        if (does_gd_meet_server_quorum (this, NULL, _gf_false)) {
+                ret = 0;
+                goto out;
+        }
+
+        if (glusterd_is_volume_in_server_quorum (volinfo)) {
+                ret = -1;
+                *op_errstr = gf_strdup (errstr);
+                goto out;
+        }
+        ret = 0;
+out:
+        return ret;
+}
+
 int
 glusterd_validate_and_create_brickpath (glusterd_brickinfo_t *brickinfo,
                                         uuid_t volume_id, char **op_errstr,