Btrfs: Add flush barriers on commit

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index f1b56eb77b1d..9ab4086d463c 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -64,13 +64,14 @@ static void btrfs_put_super (struct super_block * sb)
 
 enum {
         Opt_subvol, Opt_nodatasum, Opt_nodatacow, Opt_max_extent,
-        Opt_alloc_start, Opt_err,
+        Opt_alloc_start, Opt_nobarrier, Opt_err,
 };
 
 static match_table_t tokens = {
         {Opt_subvol, "subvol=%s"},
         {Opt_nodatasum, "nodatasum"},
         {Opt_nodatacow, "nodatacow"},
+        {Opt_nobarrier, "nobarrier"},
         {Opt_max_extent, "max_extent=%s"},
         {Opt_alloc_start, "alloc_start=%s"},
         {Opt_err, NULL}
@@ -148,6 +149,12 @@ static int parse_options (char * options,
                                 btrfs_set_opt(info->mount_opt, NODATASUM);
                         }
                         break;
+                case Opt_nobarrier:
+                        if (info) {
+                                printk("btrfs: turning off barriers\n");
+                                btrfs_set_opt(info->mount_opt, NOBARRIER);
+                        }
+                        break;
                 case Opt_max_extent:
                         if (info) {
                                 char *num = match_strdup(&args[0]);