cli/glusterd: add/remove brick fixes for arbiter volumes

1.Provide a command to convert replica 2 volumes to arbiter volumes.
Existing self-heal logic will automatically heal the file hierarchy into
the arbiter brick, the progress of which can be monitored using the
heal info command.

Syntax: gluster volume add-brick <VOLNAME> replica 3 arbiter 1
<HOST:arbiter-brick-path>

2. Add checks when removing bricks from arbiter volumes:
- When converting from arbiter to replica 2 volume, allow only arbiter
  brick to be removed.
- When converting from arbiter to plain distribute volume, allow only if
  arbiter is one of the bricks that is removed.

3. Some clean-up:
- Use GD_MSG_DICT_GET_SUCCESS instead of GD_MSG_DICT_GET_FAILED to
log messages that are not failures.
- Remove unused variable `brick_list`
- Move 'brickinfo->group' related functions to glusted-utils.

Change-Id: Ic87b8c7e4d7d3ab03f93e7b9f372b314d80947ce
BUG: 1318289
Signed-off-by: Ravishankar N <ravishankar@redhat.com>
Reviewed-on: http://review.gluster.org/14126
Smoke: Gluster Build System <jenkins@build.gluster.com>
CentOS-regression: Gluster Build System <jenkins@build.gluster.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Atin Mukherjee <amukherj@redhat.com>

1 files changed, 37 insertions, 0 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.c b/xlators/mgmt/glusterd/src/glusterd-utils.c
index 89c6d2dfa18..19173a4d015 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.c
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.c
@@ -11418,3 +11418,40 @@ out:
         gf_msg_debug ("glusterd", 0, "Returning with ret");
         return ret;
 }
+
+void
+assign_brick_groups (glusterd_volinfo_t *volinfo)
+{
+        glusterd_brickinfo_t    *brickinfo      = NULL;
+        uint16_t                group_num       = 0;
+        int                     in_group        = 0;
+
+        list_for_each_entry (brickinfo, &volinfo->bricks, brick_list) {
+                brickinfo->group = group_num;
+                if (++in_group >= volinfo->replica_count) {
+                        in_group = 0;
+                        ++group_num;
+                }
+        }
+}
+
+glusterd_brickinfo_t*
+get_last_brick_of_brick_group (glusterd_volinfo_t *volinfo,
+                               glusterd_brickinfo_t *brickinfo)
+{
+        glusterd_brickinfo_t  *next = NULL;
+        glusterd_brickinfo_t  *last = NULL;
+        int ret = -1;
+
+        last = brickinfo;
+        for (;;) {
+                next = list_next (last, &volinfo->bricks,
+                                  glusterd_brickinfo_t, brick_list);
+                if (!next || (next->group != brickinfo->group)) {
+                        break;
+                }
+                last = next;
+        }
+
+        return last;
+}