glusterd/snapshot: Activation and De-activation of snapshot

Previously, snapshots by default were activated on creation and there was
no option to activate or deactivate them on demand.

This will allow the user to activate and deactivate on demand.
The CLI goes as follows

1) Activate the snap using a command "gluster snapshot activate <snapname> [force]"
2) Deactivate the snap using a command "gluster snapshot deactivate <snapname>"

Note: Even now the snapshot will be activated during creation.

Change-Id: I0946d800780f26c63fa1fcaf29aabc900140448f
BUG: 1061685
Signed-off-by: Joseph Fernandes <josferna@redhat.com>
Reviewed-on: http://review.gluster.org/7476
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijaikumar Mallikarjuna <vmallika@redhat.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 149 insertions, 7 deletions

diff --git a/cli/src/cli-cmd-parser.c b/cli/src/cli-cmd-parser.c
index de0654a744b..e7f41fa7203 100644
--- a/cli/src/cli-cmd-parser.c
+++ b/cli/src/cli-cmd-parser.c
@@ -3297,6 +3297,102 @@ out:
         return ret;
 }
 
+/* snapshot activate <snapname> [force]
+ * @arg-0, dict     : Request Dictionary to be sent to server side.
+ * @arg-1, words    : Contains individual words of CLI command.
+ * @arg-2, wordcount: Contains number of words present in the CLI command.
+ *
+ * return value : -1 on failure
+ *                 0 on success
+ */
+int
+cli_snap_activate_parse (dict_t *dict, const char **words, int wordcount)
+{
+
+        int ret = -1;
+        int flags = 0;
+
+        GF_ASSERT (words);
+        GF_ASSERT (dict);
+
+        if ((wordcount < 3) || (wordcount > 4)) {
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+
+        ret = dict_set_str (dict, "snapname", (char *)words[2]);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to save snap-name %s",
+                        words[2]);
+                goto out;
+        }
+
+        if (wordcount == 4) {
+                if (!strcmp("force", (char *)words[3])) {
+                        flags = GF_CLI_FLAG_OP_FORCE;
+                } else {
+                        gf_log ("cli", GF_LOG_ERROR, "Invalid option");
+                        ret = -1;
+                        goto out;
+                }
+        }
+        ret = dict_set_int32 (dict, "flags", flags);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to save force option");
+                goto out;
+        }
+out:
+        return ret;
+}
+
+/* snapshot deactivate <snapname>
+ * @arg-0, dict     : Request Dictionary to be sent to server side.
+ * @arg-1, words    : Contains individual words of CLI command.
+ * @arg-2, wordcount: Contains number of words present in the CLI command.
+ *
+ * return value : -1 on failure
+ *                 0 on success
+ *                 1 if user cancelled the request
+ */
+int
+cli_snap_deactivate_parse (dict_t *dict, const char **words, int wordcount,
+                        struct cli_state *state)
+{
+
+        int             ret             = -1;
+        gf_answer_t     answer          = GF_ANSWER_NO;
+        const char     *question        = "Deactivating snap will make its "
+                                          "data inaccessible. Do you want to "
+                                          "continue?";
+
+
+        GF_ASSERT (words);
+        GF_ASSERT (dict);
+
+        if ((wordcount != 3)) {
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+
+        ret = dict_set_str (dict, "snapname", (char *)words[2]);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to save snap-name %s",
+                        words[2]);
+                goto out;
+        }
+
+        answer = cli_cmd_get_confirmation (state, question);
+        if (GF_ANSWER_NO == answer) {
+                ret = 1;
+                gf_log ("cli", GF_LOG_DEBUG, "User cancelled "
+                        "snapshot deactivate operation");
+                goto out;
+        }
+
+out:
+        return ret;
+}
+
 /* snapshot delete <snapname>
  * @arg-0, dict     : Request Dictionary to be sent to server side.
  * @arg-1, words    : Contains individual words of CLI command.
@@ -3648,9 +3744,9 @@ cli_cmd_snapshot_parse (const char **words, int wordcount, dict_t **options,
         dict_t             *dict      = NULL;
         gf1_cli_snapshot   type       = GF_SNAP_OPTION_TYPE_NONE;
         char               *w         = NULL;
-        char               *opwords[] = {"create", "delete", "restore", "start",
-                                         "stop", "list", "status", "config",
-                                         "info", NULL};
+        char               *opwords[] = {"create", "delete", "restore",
+                                        "activate", "deactivate", "list",
+                                        "status", "config", "info", NULL};
         char               *invalid_snapnames[] = {"description", "force",
                                                   "volume", NULL};
 
@@ -3690,8 +3786,11 @@ cli_cmd_snapshot_parse (const char **words, int wordcount, dict_t **options,
                 type = GF_SNAP_OPTION_TYPE_RESTORE;
         } else if (!strcmp (w, "status")) {
                 type = GF_SNAP_OPTION_TYPE_STATUS;
+        } else if (!strcmp (w, "activate")) {
+                type = GF_SNAP_OPTION_TYPE_ACTIVATE;
+        } else if (!strcmp (w, "deactivate")) {
+                type = GF_SNAP_OPTION_TYPE_DEACTIVATE;
         }
-
         if (type != GF_SNAP_OPTION_TYPE_CONFIG) {
                 ret = dict_set_int32 (dict, "hold_snap_locks", _gf_true);
                 if (ret) {
@@ -3702,6 +3801,18 @@ cli_cmd_snapshot_parse (const char **words, int wordcount, dict_t **options,
                 }
         }
 
+        /* Following commands does not require volume locks  */
+        if (type == GF_SNAP_OPTION_TYPE_STATUS ||
+            type == GF_SNAP_OPTION_TYPE_ACTIVATE ||
+            type == GF_SNAP_OPTION_TYPE_DEACTIVATE) {
+                ret = dict_set_int32 (dict, "hold_vol_locks", _gf_false);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Setting volume lock "
+                                "flag failed");
+                        goto out;
+                }
+        }
+
         /* Check which op is intended */
         switch (type) {
         case GF_SNAP_OPTION_TYPE_CREATE:
@@ -3764,8 +3875,12 @@ cli_cmd_snapshot_parse (const char **words, int wordcount, dict_t **options,
                  */
                 ret = cli_snap_delete_parse (dict, words, wordcount, state);
                 if (ret) {
-                        gf_log ("cli", GF_LOG_ERROR, "Failed to parse "
-                                "snapshot delete command");
+                        /* A positive ret value means user cancelled
+                        * the command */
+                        if (ret < 0) {
+                                gf_log ("cli", GF_LOG_ERROR, "Failed to parse "
+                                        "snapshot delete command");
+                        }
                         goto out;
                 }
                 break;
@@ -3816,7 +3931,34 @@ cli_cmd_snapshot_parse (const char **words, int wordcount, dict_t **options,
                         goto out;
                 }
                 break;
-
+                case GF_SNAP_OPTION_TYPE_ACTIVATE:
+                        /* Syntax:
+                        * snapshot activate <snapname> [force]
+                        */
+                        ret = cli_snap_activate_parse (dict, words, wordcount);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Failed to parse "
+                                        "start command");
+                                goto out;
+                        }
+                        break;
+                case GF_SNAP_OPTION_TYPE_DEACTIVATE:
+                        /* Syntax:
+                        * snapshot deactivate <snapname>
+                        */
+                        ret = cli_snap_deactivate_parse (dict, words, wordcount,
+                                state);
+                        if (ret) {
+                                /* A positive ret value means user cancelled
+                                 * the command */
+                                if (ret < 0) {
+                                        gf_log ("cli", GF_LOG_ERROR,
+                                                "Failed to parse deactivate "
+                                                "command");
+                                }
+                                goto out;
+                        }
+                        break;
         default:
                 gf_log ("", GF_LOG_ERROR, "Opword Mismatch");
                 goto out;