gfs2: Silence gcc format-truncation warning

Enlarge sd_fsname to be big enough for the longest long lock table name
and an arbitrary journal number.  This silences two -Wformat-truncation
warnings with gcc 7.1.1.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

fs/gfs2/incore.h

@@ -833,7 +833,7 @@ struct gfs2_sbd {
 	atomic_t sd_freeze_state;
 	struct mutex sd_freeze_mutex;
 
-	char sd_fsname[GFS2_FSNAME_LEN];
+	char sd_fsname[GFS2_FSNAME_LEN + 3 * sizeof(int) + 2];
 	char sd_table_name[GFS2_FSNAME_LEN];
 	char sd_proto_name[GFS2_FSNAME_LEN];
 

fs/gfs2/ops_fstype.c

@@ -1113,7 +1113,7 @@ static int fill_super(struct super_block *sb, struct gfs2_args *args, int silent
 		return error;
 	}
 
-	snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s", sdp->sd_table_name);
+	snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s", sdp->sd_table_name);
 
 	error = gfs2_sys_fs_add(sdp);
 	/*
@@ -1159,10 +1159,10 @@ static int fill_super(struct super_block *sb, struct gfs2_args *args, int silent
 	}
 
 	if (sdp->sd_args.ar_spectator)
-		snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.s",
+		snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.s",
 			 sdp->sd_table_name);
 	else
-		snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.%u",
+		snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.%u",
 			 sdp->sd_table_name, sdp->sd_lockstruct.ls_jid);
 
 	error = init_inodes(sdp, DO);