glusterd/snapshot: Update fstype and fsuuid

Update fstype and fsuuid before creating missed snapshot

Change-Id: Ie9af0065fab288bd1c1a26396428f0cee6335f97
BUG: 1109142
Signed-off-by: Avra Sengupta <asengupt@redhat.com>
Reviewed-on: http://review.gluster.org/8062
Reviewed-by: Rajesh Joseph <rjoseph@redhat.com>
Tested-by: Justin Clift <justin@gluster.org>
Reviewed-by: Krishnan Parthasarathi <kparthas@redhat.com>
Tested-by: Krishnan Parthasarathi <kparthas@redhat.com>

3 files changed, 62 insertions, 26 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-handshake.c b/xlators/mgmt/glusterd/src/glusterd-handshake.c
index 115dd8bd145..7be1e9017bd 100644
--- a/xlators/mgmt/glusterd/src/glusterd-handshake.c
+++ b/xlators/mgmt/glusterd/src/glusterd-handshake.c
@@ -347,16 +347,17 @@ int32_t
 glusterd_create_missed_snap (glusterd_missed_snap_info *missed_snapinfo,
                              glusterd_snap_op_t *snap_opinfo)
 {
-        char                        *device      = NULL;
-        glusterd_conf_t             *priv        = NULL;
-        glusterd_snap_t             *snap        = NULL;
-        glusterd_volinfo_t          *snap_vol    = NULL;
-        glusterd_volinfo_t          *volinfo     = NULL;
-        glusterd_brickinfo_t        *brickinfo   = NULL;
-        int32_t                      ret         = -1;
-        int32_t                      i           = 0;
-        uuid_t                       snap_uuid   = {0,};
-        xlator_t                    *this        = NULL;
+        char                        *device           = NULL;
+        char                         fstype[NAME_MAX] = "";
+        glusterd_conf_t             *priv             = NULL;
+        glusterd_snap_t             *snap             = NULL;
+        glusterd_volinfo_t          *snap_vol         = NULL;
+        glusterd_volinfo_t          *volinfo          = NULL;
+        glusterd_brickinfo_t        *brickinfo        = NULL;
+        int32_t                      ret              = -1;
+        int32_t                      i                = 0;
+        uuid_t                       snap_uuid        = {0,};
+        xlator_t                    *this             = NULL;
 
         this = THIS;
         GF_ASSERT (this);
@@ -431,6 +432,18 @@ glusterd_create_missed_snap (glusterd_missed_snap_info *missed_snapinfo,
         strncpy (brickinfo->device_path, device,
                  sizeof(brickinfo->device_path));
 
+        /* Update the backend file-system type of snap brick in
+         * snap volinfo. */
+        ret = glusterd_update_fstype (snap_opinfo->brick_path, brickinfo,
+                                      fstype, sizeof(fstype));
+        if (ret) {
+                gf_log (this->name, GF_LOG_ERROR, "Failed to update "
+                        "file-system type for %s brick",
+                        brickinfo->path);
+                /* We should not fail snapshot operation if we fail to get
+                 * the file-system type */
+        }
+
         ret = glusterd_take_lvm_snapshot (brickinfo, snap_opinfo->brick_path);
         if (ret) {
                 gf_log (this->name, GF_LOG_ERROR,
@@ -439,6 +452,21 @@ glusterd_create_missed_snap (glusterd_missed_snap_info *missed_snapinfo,
                 goto out;
         }
 
+        /* After the snapshot both the origin brick (LVM brick) and
+         * the snapshot brick will have the same file-system UUID. This
+         * will cause lot of problems at mount time. Therefore we must
+         * generate a new UUID for the snapshot brick
+         */
+        ret = glusterd_update_fs_uuid (brickinfo);
+        if (ret) {
+                gf_log (this->name, GF_LOG_ERROR, "Failed to update "
+                        "file-system uuid for %s brick", brickinfo->path);
+                /* Failing to update UUID should not cause snapshot failure.
+                 * Currently UUID is updated only for XFS and ext2/ext3/ext4
+                 * file-system.
+                 */
+        }
+
         /* Create and mount the snap brick */
         ret = glusterd_snap_brick_create (snap_vol, brickinfo,
                                           snap_opinfo->brick_num - 1);
@@ -449,6 +477,7 @@ glusterd_create_missed_snap (glusterd_missed_snap_info *missed_snapinfo,
                         snap_vol->snapshot->snapname);
                 goto out;
         }
+
         brickinfo->snap_status = 0;
         ret = glusterd_store_volinfo (snap_vol,
                                       GLUSTERD_VOLINFO_VER_AC_NONE);
@@ -459,7 +488,6 @@ glusterd_create_missed_snap (glusterd_missed_snap_info *missed_snapinfo,
                 goto out;
         }
 
-
         ret = glusterd_brick_start (snap_vol, brickinfo, _gf_false);
         if (ret) {
                 gf_log (this->name, GF_LOG_WARNING, "starting the "
diff --git a/xlators/mgmt/glusterd/src/glusterd-snapshot.c b/xlators/mgmt/glusterd/src/glusterd-snapshot.c
index 8b3ffd5b760..117004b4452 100644
--- a/xlators/mgmt/glusterd/src/glusterd-snapshot.c
+++ b/xlators/mgmt/glusterd/src/glusterd-snapshot.c
@@ -3767,13 +3767,13 @@ out:
  *
  * @return 0 on success and -1 on failure
  */
-static int
-glusterd_update_fstype (glusterd_brickinfo_t *orig_brickinfo,
-                        glusterd_brickinfo_t *snap_brickinfo)
+int
+glusterd_update_fstype (char *orig_brick_path,
+                        glusterd_brickinfo_t *snap_brickinfo,
+                        char *fstype, size_t fslen)
 {
         int32_t               ret               = -1;
         char                 *mnt_pt            = NULL;
-        char                 *fstype            = NULL;
         char                  buff [PATH_MAX]   = "";
         char                  msg [PATH_MAX]    = "";
         char                 *cmd               = NULL;
@@ -3784,19 +3784,18 @@ glusterd_update_fstype (glusterd_brickinfo_t *orig_brickinfo,
 
         this = THIS;
         GF_ASSERT (this);
-        GF_ASSERT (orig_brickinfo);
+        GF_ASSERT (orig_brick_path);
         GF_ASSERT (snap_brickinfo);
-
-        fstype = orig_brickinfo->fstype;
+        GF_ASSERT (fstype);
 
         /* If the file-system type is not set then set the file-system type
          * in origin brickinfo */
         if (0 == fstype [0]) {
-                ret = glusterd_get_brick_root (orig_brickinfo->path, &mnt_pt);
+                ret = glusterd_get_brick_root (orig_brick_path, &mnt_pt);
                 if (ret) {
                         gf_log (this->name, GF_LOG_ERROR, "getting the root "
                                 "of the brick (%s) failed ",
-                                orig_brickinfo->path);
+                                orig_brick_path);
                         goto out;
                 }
 
@@ -3805,14 +3804,14 @@ glusterd_update_fstype (glusterd_brickinfo_t *orig_brickinfo,
                 if (!entry) {
                         gf_log (this->name, GF_LOG_ERROR, "getting the mount "
                                 "entry for the brick (%s) failed",
-                                orig_brickinfo->path);
+                                orig_brick_path);
                         ret = -1;
                         goto out;
                 }
 
                 /* Update the origin brickinfo with the backend file-system
                  * type */
-                snprintf (fstype, sizeof (orig_brickinfo->fstype), "%s",
+                snprintf (fstype, fslen, "%s",
                           entry->mnt_type);
         }
 
@@ -3866,7 +3865,9 @@ glusterd_add_brick_to_snap_volume (dict_t *dict, dict_t *rsp_dict,
 
         /* Update the backend file-system type of snap brick in
          * snap volinfo. */
-        ret = glusterd_update_fstype (original_brickinfo, snap_brickinfo);
+        ret = glusterd_update_fstype (original_brickinfo->path, snap_brickinfo,
+                                      original_brickinfo->fstype,
+                                      sizeof(original_brickinfo->fstype));
         if (ret) {
                 gf_log (this->name, GF_LOG_ERROR, "Failed to update "
                         "file-system type for %s brick",
@@ -3976,7 +3977,7 @@ out:
  *
  * @return 0 on success and -1 on failure
  */
-static int
+int
 glusterd_update_fs_uuid (glusterd_brickinfo_t *brickinfo)
 {
         int32_t         ret                     = -1;
@@ -4140,7 +4141,6 @@ glusterd_take_brick_snapshot (dict_t *dict, glusterd_volinfo_t *snap_vol,
                  */
         }
 
-
         /* create the complete brick here */
         ret = glusterd_snap_brick_create (snap_vol, brickinfo, brick_count);
         if (ret) {
diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.h b/xlators/mgmt/glusterd/src/glusterd-utils.h
index 2a22831fe41..1764f642d3f 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.h
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.h
@@ -890,6 +890,7 @@ glusterd_snapd_set_online_status (glusterd_volinfo_t *volinfo,
 
 int
 glusterd_restart_snapds (glusterd_conf_t *priv);
+/* End snapd functions */
 
 int32_t
 glusterd_check_and_set_config_limit (glusterd_conf_t *priv);
@@ -897,10 +898,17 @@ glusterd_check_and_set_config_limit (glusterd_conf_t *priv);
 int32_t
 glusterd_is_snap_soft_limit_reached (glusterd_volinfo_t *volinfo,
                                      dict_t *dict);
-/* End snapd functions */
 
 int32_t
 glusterd_find_brick_mount_path (char *brick_path, int32_t brick_count,
                                 char **brick_mount_path);
 
+int
+glusterd_update_fstype (char *orig_brick_path,
+                        glusterd_brickinfo_t *snap_brickinfo,
+                        char *fstype, size_t fslen);
+
+int
+glusterd_update_fs_uuid (glusterd_brickinfo_t *brickinfo);
+
 #endif