glusterd: populate brickinfo->real_path conditionally

Backport of http://review.gluster.org/13965

glusterd_brickinfo_new_from_brick () is called from multiple places and one of
them is glusterd_brick_rpc_notify where its very well possible that an
underlying brick's file system has crashed and a disconnect event has been
received. In this case glusterd tries to build the brickinfo from the brickid in
the RPC request, however the same fails as glusterd_brickinfo_new_from_brick ()
fails from realpath.

Fix is to skip populating real_path if its a disconnect event.

Change-Id: I9d9149c64a9cf2247abb731f219c1b1eef037960
BUG: 1326174
Signed-off-by: Atin Mukherjee <amukherj@redhat.com>
Reviewed-on: http://review.gluster.org/13965
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: Jeff Darcy <jdarcy@redhat.com>
Reviewed-on: http://review.gluster.org/13973

1 files changed, 24 insertions, 16 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.c b/xlators/mgmt/glusterd/src/glusterd-utils.c
index 4d4f22ee7e9..f3d2d8665b3 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.c
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.c
@@ -1063,7 +1063,8 @@ out:
 
 int32_t
 glusterd_brickinfo_new_from_brick (char *brick,
-                                   glusterd_brickinfo_t **brickinfo)
+                                   glusterd_brickinfo_t **brickinfo,
+                                   gf_boolean_t construct_real_path)
 {
         char                   *hostname      = NULL;
         char                   *path          = NULL;
@@ -1111,19 +1112,22 @@ glusterd_brickinfo_new_from_brick (char *brick,
         strncpy (new_brickinfo->hostname, hostname, 1024);
         strncpy (new_brickinfo->path, path, 1024);
 
-        if (!realpath (new_brickinfo->path, abspath)) {
-                /* ENOENT indicates that brick path has not been created which
-                 * is a valid scenario */
-                if (errno != ENOENT) {
-                        gf_msg (this->name, GF_LOG_CRITICAL, errno,
-                                GD_MSG_BRICKINFO_CREATE_FAIL, "realpath () failed for "
-                                "brick %s. The underlying filesystem may be in bad "
-                                "state", new_brickinfo->path);
-                        ret = -1;
-                        goto out;
+        if (construct_real_path) {
+                if (!realpath (new_brickinfo->path, abspath)) {
+                        /* ENOENT indicates that brick path has not been created
+                         * which is a valid scenario */
+                        if (errno != ENOENT) {
+                                gf_msg (this->name, GF_LOG_CRITICAL, errno,
+                                        GD_MSG_BRICKINFO_CREATE_FAIL, "realpath"
+                                        " () failed for brick %s. The "
+                                        "underlying filesystem may be in bad "
+                                        "state", new_brickinfo->path);
+                                ret = -1;
+                                goto out;
+                        }
                 }
+                strncpy (new_brickinfo->real_path, abspath, strlen(abspath));
         }
-        strncpy (new_brickinfo->real_path, abspath, strlen(abspath));
 
         *brickinfo = new_brickinfo;
 
@@ -1424,7 +1428,8 @@ out:
 int32_t
 glusterd_volume_brickinfo_get_by_brick (char *brick,
                                         glusterd_volinfo_t *volinfo,
-                                        glusterd_brickinfo_t **brickinfo)
+                                        glusterd_brickinfo_t **brickinfo,
+                                        gf_boolean_t construct_real_path)
 {
         int32_t                 ret = -1;
         glusterd_brickinfo_t    *tmp_brickinfo = NULL;
@@ -1432,7 +1437,8 @@ glusterd_volume_brickinfo_get_by_brick (char *brick,
         GF_ASSERT (brick);
         GF_ASSERT (volinfo);
 
-        ret = glusterd_brickinfo_new_from_brick (brick, &tmp_brickinfo);
+        ret = glusterd_brickinfo_new_from_brick (brick, &tmp_brickinfo,
+                                                 construct_real_path);
         if (ret)
                 goto out;
 
@@ -5783,7 +5789,8 @@ glusterd_new_brick_validate (char *brick, glusterd_brickinfo_t *brickinfo,
         GF_ASSERT (op_errstr);
 
         if (!brickinfo) {
-                ret = glusterd_brickinfo_new_from_brick (brick, &newbrickinfo);
+                ret = glusterd_brickinfo_new_from_brick (brick, &newbrickinfo,
+                                                         _gf_true);
                 if (ret)
                         goto out;
                 is_allocated = _gf_true;
@@ -10122,7 +10129,8 @@ gd_should_i_start_rebalance  (glusterd_volinfo_t *volinfo) {
                                 goto out;
                         ret = glusterd_volume_brickinfo_get_by_brick (brickname,
                                                                       volinfo,
-                                                                      &brick);
+                                                                      &brick,
+                                                                      _gf_true);
                         if (ret)
                                 goto out;
                         if (gf_uuid_compare (MY_UUID, brick->uuid) == 0) {