cluster/dht: Rebalance will be a new glusterfs process

rebalance will not use any maintainance clients. It is replaced by syncops,
with the volfile. Brickop (communication between glusterd<->glusterfs process)
is used for status and stop commands.

Dept-first traversal of dir is maintained, but data is migrated as and when
encounterd.
fix-layout (dir)
do
        Complete migrate-data of dir
        fix-layout (subdir)
done

Rebalance state is saved in the vol file, for restart-ability.
A disconnect event and pidfile state determine the defrag-status

Signed-off-by: shishirng <shishirng@gluster.com>
Change-Id: Iec6c80c84bbb2142d840242c28db3d5f5be94d01
BUG: 763844
Reviewed-on: http://review.gluster.com/2540
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Amar Tumballi <amarts@redhat.com>

2 files changed, 31 insertions, 70 deletions

diff --git a/cli/src/cli-cmd-volume.c b/cli/src/cli-cmd-volume.c
index 6bea948e9..6ab1515e3 100644
--- a/cli/src/cli-cmd-volume.c
+++ b/cli/src/cli-cmd-volume.c
@@ -731,7 +731,7 @@ cli_cmd_volume_defrag_cbk (struct cli_state *state, struct cli_cmd_word *word,
         if (!dict)
                 goto out;
 
-        if (!((wordcount == 4) || (wordcount == 5) || (wordcount == 6))) {
+        if (!((wordcount == 4) || (wordcount == 5))) {
                 cli_usage_out (word->pattern);
                 parse_error = 1;
                 goto out;
@@ -741,7 +741,7 @@ cli_cmd_volume_defrag_cbk (struct cli_state *state, struct cli_cmd_word *word,
                 index = 3;
         } else {
                 if (strcmp (words[3], "fix-layout") &&
-                    strcmp (words[3], "migrate-data")) {
+                    strcmp (words[3], "start")) {
                         cli_usage_out (word->pattern);
                         parse_error = 1;
                         goto out;
@@ -750,7 +750,7 @@ cli_cmd_volume_defrag_cbk (struct cli_state *state, struct cli_cmd_word *word,
         }
 
 	if (strcmp (words[index], "start") && strcmp (words[index], "stop") &&
-            strcmp (words[index], "status")) {
+            strcmp (words[index], "status") && strcmp (words[index], "force")) {
 	        cli_usage_out (word->pattern);
 		parse_error = 1;
 		goto out;
@@ -766,27 +766,19 @@ cli_cmd_volume_defrag_cbk (struct cli_state *state, struct cli_cmd_word *word,
                         goto out;
         }
         if (wordcount == 5) {
-                ret = dict_set_str (dict, "start-type", (char *)words[3]);
-                if (ret)
-                        goto out;
-                ret = dict_set_str (dict, "command", (char *)words[4]);
-                if (ret)
-                        goto out;
-        }
-
-        /* 'force' option is valid only for the 'migrate-data' key */
-        if (wordcount == 6) {
-                if (strcmp (words[3], "migrate-data") ||
-                    strcmp (words[4], "start") ||
-                    strcmp (words[5], "force")) {
+               if ((strcmp (words[3], "fix-layout") ||
+                    strcmp (words[4], "start")) &&
+                    (strcmp (words[3], "start") ||
+                    strcmp (words[4], "force"))) {
                         cli_usage_out (word->pattern);
                         parse_error = 1;
                         goto out;
                 }
-                ret = dict_set_str (dict, "start-type", "migrate-data-force");
+
+                ret = dict_set_str (dict, "option", (char *)words[4]);
                 if (ret)
                         goto out;
-                ret = dict_set_str (dict, "command", (char *)words[4]);
+                ret = dict_set_str (dict, "command", (char *)words[3]);
                 if (ret)
                         goto out;
         }
@@ -1776,7 +1768,7 @@ struct cli_cmd volume_cmds[] = {
           cli_cmd_volume_remove_brick_cbk,
           "remove brick from volume <VOLNAME>"},
 
-        { "volume rebalance <VOLNAME> [fix-layout|migrate-data] {start|stop|status} [force]",
+        { "volume rebalance <VOLNAME> [fix-layout] {start|stop|status} [force]",
           cli_cmd_volume_defrag_cbk,
           "rebalance operations"},
 
diff --git a/cli/src/cli-rpc-ops.c b/cli/src/cli-rpc-ops.c
index 6ed380bff..d1888415c 100644
--- a/cli/src/cli-rpc-ops.c
+++ b/cli/src/cli-rpc-ops.c
@@ -1052,9 +1052,9 @@ gf_cli3_1_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
                                           volname);
                 } else {
                         snprintf (msg, sizeof (msg),
-                                  "stopped rebalance process of volume %s \n"
-                                  "(after rebalancing %"PRId64" files totaling"
-                                  " %"PRId64" bytes)", volname, files, size);
+                                 "Stopped rebalance process on volume %s \n"
+                                 "(after rebalancing %"PRId64" bytes - "
+                                 "%"PRId64" files)", volname, size, files);
                 }
                 goto done;
         }
@@ -1065,7 +1065,7 @@ gf_cli3_1_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
                                           "%s", rsp.op_errstr);
                         else
                                 snprintf (msg, sizeof (msg),
-                                          "failed to get the status of "
+                                          "Failed to get the status of "
                                           "rebalance process");
                         goto done;
                 }
@@ -1074,11 +1074,8 @@ gf_cli3_1_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 case GF_DEFRAG_STATUS_NOT_STARTED:
                         status = "not started";
                         break;
-                case GF_DEFRAG_STATUS_LAYOUT_FIX_STARTED:
-                        status = "step 1: layout fix in progress";
-                        break;
-                case GF_DEFRAG_STATUS_MIGRATE_DATA_STARTED:
-                        status = "step 2: data migration in progress";
+                case GF_DEFRAG_STATUS_STARTED:
+                        status = "in progress";
                         break;
                 case GF_DEFRAG_STATUS_STOPPED:
                         status = "stopped";
@@ -1089,38 +1086,17 @@ gf_cli3_1_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 case GF_DEFRAG_STATUS_FAILED:
                         status = "failed";
                         break;
-                case GF_DEFRAG_STATUS_LAYOUT_FIX_COMPLETE:
-                        status = "step 1: layout fix complete";
-                        break;
-                case GF_DEFRAG_STATUS_MIGRATE_DATA_COMPLETE:
-                        status = "step 2: data migration complete";
-                        break;
-                case GF_DEFRAG_STATUS_PAUSED:
-                        status = "paused";
-                        break;
                 }
-                if (files && (rsp.op_errno == 1)) {
-                        snprintf (msg, sizeof (msg),
-                                  "rebalance %s: fixed layout %"PRId64,
-                                  status, files);
-                        goto done;
-                }
-                if (files && (rsp.op_errno == 6)) {
-                        snprintf (msg, sizeof (msg),
-                                  "rebalance %s: fixed layout %"PRId64,
-                                  status, files);
-                        goto done;
-                }
-                if (files) {
-                        snprintf (msg, sizeof (msg),
-                                  "rebalance %s: rebalanced %"PRId64
+                if (files || size || lookup) {
+                        snprintf (msg, sizeof(msg),
+                                  "Rebalance %s: rebalanced %"PRId64
                                   " files of size %"PRId64" (total files"
                                   " scanned %"PRId64")", status,
                                   files, size, lookup);
                         goto done;
                 }
 
-                snprintf (msg, sizeof (msg), "rebalance %s", status);
+                snprintf (msg, sizeof (msg), "Rebalance %s", status);
                 goto done;
         }
 
@@ -1129,7 +1105,7 @@ gf_cli3_1_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 snprintf (msg, sizeof (msg), "%s", rsp.op_errstr);
         else
                 snprintf (msg, sizeof (msg),
-                          "starting rebalance on volume %s has been %s",
+                          "Starting rebalance on volume %s has been %s",
                           volname, (rsp.op_ret) ? "unsuccessful":
                           "successful");
 
@@ -1398,24 +1374,18 @@ gf_cli3_remove_brick_status_cbk (struct rpc_req *req, struct iovec *iov,
         case GF_DEFRAG_STATUS_NOT_STARTED:
                 status = "not started";
                 break;
-        case GF_DEFRAG_STATUS_LAYOUT_FIX_STARTED:
-        case GF_DEFRAG_STATUS_MIGRATE_DATA_STARTED:
-        case GF_DEFRAG_STATUS_LAYOUT_FIX_COMPLETE:
+        case GF_DEFRAG_STATUS_STARTED:
                 status = "in progress";
                 break;
         case GF_DEFRAG_STATUS_STOPPED:
                 status = "stopped";
                 break;
         case GF_DEFRAG_STATUS_COMPLETE:
-        case GF_DEFRAG_STATUS_MIGRATE_DATA_COMPLETE:
                 status = "completed";
                 break;
         case GF_DEFRAG_STATUS_FAILED:
                 status = "failed";
                 break;
-        case GF_DEFRAG_STATUS_PAUSED:
-                status = "paused";
-                break;
         }
 
         if (rsp.dict.dict_len) {
@@ -2479,20 +2449,19 @@ gf_cli3_1_defrag_volume (call_frame_t *frame, xlator_t *this,
 
         if (strcmp (cmd_str, "start") == 0) {
                 cmd = GF_DEFRAG_CMD_START;
-                ret = dict_get_str (dict, "start-type", &cmd_str);
+                ret = dict_get_str (dict, "option", &cmd_str);
                 if (!ret) {
-                        if (strcmp (cmd_str, "fix-layout") == 0) {
-                                cmd = GF_DEFRAG_CMD_START_LAYOUT_FIX;
-                        }
-                        if (strcmp (cmd_str, "migrate-data") == 0) {
-                                cmd = GF_DEFRAG_CMD_START_MIGRATE_DATA;
-                        }
-                        if (strcmp (cmd_str, "migrate-data-force") == 0) {
-                                cmd = GF_DEFRAG_CMD_START_MIGRATE_DATA_FORCE;
+                        if (strcmp (cmd_str, "force") == 0) {
+                                cmd = GF_DEFRAG_CMD_START_FORCE;
                         }
                 }
                 goto done;
         }
+
+        if (strcmp (cmd_str, "fix-layout") == 0) {
+                cmd = GF_DEFRAG_CMD_START_LAYOUT_FIX;
+                goto done;
+        }
         if (strcmp (cmd_str, "stop") == 0) {
                 cmd = GF_DEFRAG_CMD_STOP;
                 goto done;