Branch b1_6

b=12769
i=green,wangdi

Add sync option to mount_lustre.c

lustre/ChangeLog

@@ -45,6 +45,11 @@ Description: omit set fsid for export NFS
 Details    : fix set/restore device id for avoid EMFILE error and mark lustre fs
 	     as FS_REQUIRES_DEV for avoid problems with generate fsid.
 
+Severity   : major
+Bugzilla   : 12769
+Description: Add sync option to mount_lustre.c
+Details    : Client loses data written to lustre after a network interruption.
+
 --------------------------------------------------------------------------------
 
 2007-07-30         Cluster File Systems, Inc. <info@clusterfs.com>

lustre/utils/mount_lustre.c

@@ -182,6 +182,7 @@ static const struct opt_map opt_map[] = {
   { "nosuid",   0, MS_NOSUID },      /* don't honor suid executables */
   { "dev",      1, MS_NODEV  },      /* interpret device files  */
   { "nodev",    0, MS_NODEV  },      /* don't interpret devices */
+  { "sync",     0, MS_SYNCHRONOUS},  /* synchronous I/O */
   { "async",    1, MS_SYNCHRONOUS},  /* asynchronous I/O */
   { "auto",     0, 0         },      /* Can be mounted using -a */
   { "noauto",   0, 0         },      /* Can only be mounted explicitly */