glusterd: copy real_path from older brickinfo during brick import

In glusterd_import_new_brick () new_brickinfo->real_path will not be populated
for the first time and hence if the underlying file system is bad for the same
brick, import will fail resulting in inconsistent configuration data.

Fix is to populate real_path from old brickinfo object.

Also there were many cases where we were unnecessarily calling realpath() and
that may cause in failure. For eg - if a remove brick is executed with a brick
whoose underlying file system has crashed, remove-brick fails since realpath()
call fails. We'd need to call realpath() here as the value is of no use.Hence
passing construct_realpath as _gf_false in glusterd_volume_brickinfo_get_by_brick ()
is a must in such cases.

Change-Id: I7ec93871dc9e616f5d565ad5e540b2f1cacaf9dc
BUG: 1335531
Signed-off-by: Atin Mukherjee <amukherj@redhat.com>
Reviewed-on: http://review.gluster.org/14306
Smoke: Gluster Build System <jenkins@build.gluster.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Kaushal M <kaushal@redhat.com>

1 files changed, 61 insertions, 34 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.c b/xlators/mgmt/glusterd/src/glusterd-utils.c
index 41e90c2faeb..89c6d2dfa18 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.c
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.c
@@ -1061,7 +1061,8 @@ out:
 int32_t
 glusterd_brickinfo_new_from_brick (char *brick,
                                    glusterd_brickinfo_t **brickinfo,
-                                   gf_boolean_t construct_real_path)
+                                   gf_boolean_t construct_real_path,
+                                   char **op_errstr)
 {
         char                   *hostname      = NULL;
         char                   *path          = NULL;
@@ -1109,7 +1110,25 @@ glusterd_brickinfo_new_from_brick (char *brick,
         strncpy (new_brickinfo->hostname, hostname, 1024);
         strncpy (new_brickinfo->path, path, 1024);
 
-        if (construct_real_path && new_brickinfo->real_path[0] == '\0') {
+        if (construct_real_path) {
+                ret = glusterd_hostname_to_uuid (new_brickinfo->hostname,
+                                                 new_brickinfo->uuid);
+                if (ret) {
+                        gf_msg (this->name, GF_LOG_ERROR, 0,
+                                GD_MSG_HOSTNAME_TO_UUID_FAIL,
+                                "Failed to convert hostname %s to uuid",
+                                hostname);
+                        if (op_errstr)
+                                gf_asprintf (op_errstr, "Host %s is not in \' "
+                                             "Peer in Cluster\' state",
+                                             new_brickinfo->hostname);
+                        goto out;
+                }
+        }
+
+        if (construct_real_path &&
+            !gf_uuid_compare (new_brickinfo->uuid, MY_UUID)
+            && new_brickinfo->real_path[0] == '\0') {
                 if (!realpath (new_brickinfo->path, abspath)) {
                         /* ENOENT indicates that brick path has not been created
                          * which is a valid scenario */
@@ -1435,7 +1454,7 @@ glusterd_volume_brickinfo_get_by_brick (char *brick,
         GF_ASSERT (volinfo);
 
         ret = glusterd_brickinfo_new_from_brick (brick, &tmp_brickinfo,
-                                                 construct_real_path);
+                                                 construct_real_path, NULL);
         if (ret)
                 goto out;
 
@@ -3122,12 +3141,8 @@ glusterd_import_new_brick (dict_t *peer_data, int32_t vol_count,
         int                     decommissioned = 0;
         glusterd_brickinfo_t    *new_brickinfo = NULL;
         char                    msg[2048] = {0};
-        xlator_t                *this     = NULL;
         char                    *brick_uuid_str = NULL;
-        char                    abspath[PATH_MAX] = {0};
 
-        this = THIS;
-        GF_ASSERT (this);
         GF_ASSERT (peer_data);
         GF_ASSERT (vol_count >= 0);
         GF_ASSERT (brickinfo);
@@ -3188,23 +3203,7 @@ glusterd_import_new_brick (dict_t *peer_data, int32_t vol_count,
         ret = dict_get_str (peer_data, key, &brick_uuid_str);
         if (ret)
                 goto out;
-
         gf_uuid_parse (brick_uuid_str, new_brickinfo->uuid);
-        if (!gf_uuid_compare(new_brickinfo->uuid, MY_UUID)) {
-                if (new_brickinfo->real_path[0] == '\0') {
-                        if (!realpath (new_brickinfo->path, abspath)) {
-                                gf_msg (this->name, GF_LOG_CRITICAL, errno,
-                                        GD_MSG_BRICKINFO_CREATE_FAIL,
-                                        "realpath() failed for brick %s. The "
-                                        "underlying file system may be in bad "
-                                        "state", new_brickinfo->path);
-                                ret = -1;
-                                goto out;
-                        }
-                        strncpy (new_brickinfo->real_path, abspath,
-                                 strlen(abspath));
-                }
-        }
 
         *brickinfo = new_brickinfo;
 out:
@@ -3219,7 +3218,7 @@ out:
  * It will be "volume" for normal volumes, and snap# like
  * snap1, snap2, for snapshot volumes
  */
-int32_t
+static int32_t
 glusterd_import_bricks (dict_t *peer_data, int32_t vol_count,
                         glusterd_volinfo_t *new_volinfo, char *prefix)
 {
@@ -3429,6 +3428,7 @@ glusterd_import_volinfo (dict_t *peer_data, int count,
         char               *parent_volname   = NULL;
         char               *volname          = NULL;
         glusterd_volinfo_t *new_volinfo      = NULL;
+        glusterd_volinfo_t *old_volinfo      = NULL;
         char               *volume_id_str    = NULL;
         char               *restored_snap    = NULL;
         char               msg[2048]         = {0};
@@ -3847,8 +3847,8 @@ glusterd_volume_disconnect_all_bricks (glusterd_volinfo_t *volinfo)
 }
 
 int32_t
-glusterd_volinfo_copy_brick_portinfo (glusterd_volinfo_t *old_volinfo,
-                                      glusterd_volinfo_t *new_volinfo)
+glusterd_volinfo_copy_brickinfo (glusterd_volinfo_t *old_volinfo,
+                                 glusterd_volinfo_t *new_volinfo)
 {
         char                    pidfile[PATH_MAX+1] = {0,};
         glusterd_brickinfo_t   *new_brickinfo       = NULL;
@@ -3856,6 +3856,7 @@ glusterd_volinfo_copy_brick_portinfo (glusterd_volinfo_t *old_volinfo,
         glusterd_conf_t        *priv                = NULL;
         int                     ret                 = 0;
         xlator_t               *this                = NULL;
+        char                    abspath[PATH_MAX]   = {0};
 
         GF_ASSERT (new_volinfo);
         GF_ASSERT (old_volinfo);
@@ -3873,10 +3874,35 @@ glusterd_volinfo_copy_brick_portinfo (glusterd_volinfo_t *old_volinfo,
                                                      &old_brickinfo);
                 if (ret == 0) {
                         new_brickinfo->port = old_brickinfo->port;
+
+                        if (old_brickinfo->real_path == '\0') {
+                                if (!realpath (new_brickinfo->path, abspath)) {
+                                        /* Here an ENOENT should also be a
+                                         * failure as the brick is expected to
+                                         * be in existance
+                                         */
+                                        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));
+                        } else {
+                                strncpy (new_brickinfo->real_path,
+                                         old_brickinfo->real_path,
+                                         strlen (old_brickinfo->real_path));
+                        }
                 }
         }
         ret = 0;
 
+out:
         return ret;
 }
 
@@ -4060,8 +4086,8 @@ glusterd_import_friend_volume (dict_t *peer_data, size_t count)
         glusterd_volinfo_t      *old_volinfo = NULL;
         glusterd_volinfo_t      *new_volinfo = NULL;
         glusterd_svc_t          *svc         = NULL;
-        gf_boolean_t            newexportvalue;
-        gf_boolean_t            oldexportvalue;
+        gf_boolean_t            newexportvalue = _gf_false;
+        gf_boolean_t            oldexportvalue = _gf_false;
         char                    *value     = NULL;
 
         GF_ASSERT (peer_data);
@@ -4092,11 +4118,12 @@ glusterd_import_friend_volume (dict_t *peer_data, size_t count)
                 (void) gd_check_and_update_rebalance_info (old_volinfo,
                                                            new_volinfo);
 
-                /* Copy brick ports from the old volinfo always. The old_volinfo
-                 * will be cleaned up and this information could be lost
+                /* Copy brick ports & real_path from the old volinfo always.
+                 * The old_volinfo will be cleaned up and this information
+                 * could be lost
                  */
-                (void) glusterd_volinfo_copy_brick_portinfo (old_volinfo,
-                                                             new_volinfo);
+                (void) glusterd_volinfo_copy_brickinfo (old_volinfo,
+                                                        new_volinfo);
 
                 (void) glusterd_delete_stale_volume (old_volinfo, new_volinfo);
                 glusterd_volinfo_unref (old_volinfo);
@@ -5913,7 +5940,7 @@ glusterd_new_brick_validate (char *brick, glusterd_brickinfo_t *brickinfo,
 
         if (!brickinfo) {
                 ret = glusterd_brickinfo_new_from_brick (brick, &newbrickinfo,
-                                                         _gf_true);
+                                                         _gf_true, NULL);
                 if (ret)
                         goto out;
                 is_allocated = _gf_true;
@@ -10266,7 +10293,7 @@ gd_should_i_start_rebalance  (glusterd_volinfo_t *volinfo) {
                         ret = glusterd_volume_brickinfo_get_by_brick (brickname,
                                                                       volinfo,
                                                                       &brick,
-                                                                      _gf_true);
+                                                                      _gf_false);
                         if (ret)
                                 goto out;
                         if (gf_uuid_compare (MY_UUID, brick->uuid) == 0) {