glusterd/thin-arbiter: Thin-arbiter integration with GD1

gluster volume create <VOLNAME> replica 2 thin-arbiter 1 <host1>:<brick1> <host2>:<brick2>
<thin-arbiter-host>:<path-to-store-replica-id-file> [force]

The changes have been made in a way that the last brick in the bricks list
will be treated as the thin-arbiter.
GD1 will be manipulated to consider replica count to be as 2 and continue creating the
volume like any other replica 2 volume but since thin-arbiter volumes need ta-brick
client xlator entries for each subvolume in fuse volfile, volfile generation is
modified in a way to inject these entries seperately in the volfile for every subvolume.

Few more additions -
1- Save the volinfo with new fields ta_bricks list and thin_arbiter_count.
2- Introduce a new option client.ta-brick-port to add remote-port to ta-brick xlator entry
   in fuse volfiles. The option can be set using the following CLI syntax -
   gluster volume set <VOLNAME> client.ta-brick-port <PORTNO.>
3- Volume Info will contain a Thin-Arbiter-path entry to distinguish
   from other replicate volumes.

Change-Id: Ib434e2313b29716f32476c6c211d282c4ef39406
Updates #687
Signed-off-by: Vishal Pandey <vpandey@redhat.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-handler.c b/xlators/mgmt/glusterd/src/glusterd-handler.c
index 576cae7b57a..a0bf409d872 100644
--- a/xlators/mgmt/glusterd/src/glusterd-handler.c
+++ b/xlators/mgmt/glusterd/src/glusterd-handler.c
@@ -357,6 +357,7 @@ glusterd_add_volume_detail_to_dict(glusterd_volinfo_t *volinfo, dict_t *volumes,
     };
     int keylen;
     glusterd_brickinfo_t *brickinfo = NULL;
+    glusterd_brickinfo_t *ta_brickinfo = NULL;
     char *buf = NULL;
     int i = 1;
     dict_t *dict = NULL;
@@ -368,6 +369,10 @@ glusterd_add_volume_detail_to_dict(glusterd_volinfo_t *volinfo, dict_t *volumes,
     xlator_t *this = NULL;
     int32_t len = 0;
 
+    char ta_brick[4096] = {
+        0,
+    };
+
     GF_ASSERT(volinfo);
     GF_ASSERT(volumes);
 
@@ -431,6 +436,11 @@ glusterd_add_volume_detail_to_dict(glusterd_volinfo_t *volinfo, dict_t *volumes,
     if (ret)
         goto out;
 
+    keylen = snprintf(key, sizeof(key), "volume%d.thin_arbiter_count", count);
+    ret = dict_set_int32n(volumes, key, keylen, volinfo->thin_arbiter_count);
+    if (ret)
+        goto out;
+
     volume_id_str = gf_strdup(uuid_utoa(volinfo->volume_id));
     if (!volume_id_str)
         goto out;
@@ -481,6 +491,23 @@ glusterd_add_volume_detail_to_dict(glusterd_volinfo_t *volinfo, dict_t *volumes,
 
         i++;
     }
+    if (volinfo->thin_arbiter_count == 1) {
+        ta_brickinfo = list_first_entry(&volinfo->ta_bricks,
+                                        glusterd_brickinfo_t, brick_list);
+        len = snprintf(ta_brick, sizeof(ta_brick), "%s:%s",
+                       ta_brickinfo->hostname, ta_brickinfo->path);
+        if ((len < 0) || (len >= sizeof(ta_brick))) {
+            ret = -1;
+            goto out;
+        }
+        buf = gf_strdup(ta_brick);
+        keylen = snprintf(key, sizeof(key), "volume%d.thin_arbiter_brick",
+                          count);
+        ret = dict_set_dynstrn(volumes, key, keylen, buf);
+        if (ret)
+            goto out;
+    }
+
     ret = glusterd_add_arbiter_info_to_bricks(volinfo, volumes, count);
     if (ret)
         goto out;