Btrfs: Add mount -o nodatasum to turn of file data checksumming

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

1 files changed, 15 insertions, 2 deletions

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index ffa02872c4d6..ad4f280ec777 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -61,11 +61,12 @@ static void btrfs_put_super (struct super_block * sb)
 }
 
 enum {
-        Opt_subvol, Opt_err,
+        Opt_subvol, Opt_nodatasum, Opt_err,
 };
 
 static match_table_t tokens = {
         {Opt_subvol, "subvol=%s"},
+        {Opt_nodatasum, "nodatasum"},
         {Opt_err, NULL}
 };
 
@@ -74,7 +75,12 @@ static int parse_options (char * options,
                           char **subvol_name)
 {
         char * p;
+        struct btrfs_fs_info *info = NULL;
         substring_t args[MAX_OPT_ARGS];
+
+        if (root)
+                info = root->fs_info;
+
         if (!options)
                 return 1;
 
@@ -86,7 +92,12 @@ static int parse_options (char * options,
                 token = match_token(p, tokens, args);
                 switch (token) {
                 case Opt_subvol:
-                        *subvol_name = match_strdup(&args[0]);
+                        if (subvol_name)
+                                *subvol_name = match_strdup(&args[0]);
+                        break;
+                case Opt_nodatasum:
+                        if (root)
+                                btrfs_set_opt(info->mount_opt, NODATASUM);
                         break;
                 default:
                         return 0;
@@ -143,6 +154,8 @@ static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
                 goto fail_close;
         }
 
+        parse_options((char *)data, tree_root, NULL);
+
         /* this does the super kobj at the same time */
         err = btrfs_sysfs_add_super(tree_root->fs_info);
         if (err)