btrfs: Add datacow mount option.

Add datacow mount option to enable copy-on-write with
remount option.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
This commit is contained in:
Qu Wenruo 2014-01-06 09:58:31 +08:00 committed by Chris Mason
parent bd0330ad21
commit a258af7a3e
2 changed files with 10 additions and 3 deletions

View File

@ -154,9 +154,10 @@ Options with (*) are default options and will not show in the mount options.
(non-battery-backed) write-back cache, nobarrier option will lead to
filesystem corruption on a system crash or power loss.
datacow(*)
nodatacow
Disable data copy-on-write for newly created files. Implies nodatasum,
and disables all compression.
Enable/disable data copy-on-write for newly created files.
Nodatacow implies nodatasum, and disables all compression.
nodatasum
Disable data checksumming for newly created files.

View File

@ -324,7 +324,7 @@ enum {
Opt_check_integrity, Opt_check_integrity_including_extent_data,
Opt_check_integrity_print_mask, Opt_fatal_errors, Opt_rescan_uuid_tree,
Opt_commit_interval, Opt_barrier, Opt_nodefrag, Opt_nodiscard,
Opt_noenospc_debug, Opt_noflushoncommit, Opt_acl,
Opt_noenospc_debug, Opt_noflushoncommit, Opt_acl, Opt_datacow,
Opt_err,
};
@ -335,6 +335,7 @@ static match_table_t tokens = {
{Opt_device, "device=%s"},
{Opt_nodatasum, "nodatasum"},
{Opt_nodatacow, "nodatacow"},
{Opt_datacow, "datacow"},
{Opt_nobarrier, "nobarrier"},
{Opt_barrier, "barrier"},
{Opt_max_inline, "max_inline=%s"},
@ -446,6 +447,11 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
btrfs_set_opt(info->mount_opt, NODATACOW);
btrfs_set_opt(info->mount_opt, NODATASUM);
break;
case Opt_datacow:
if (btrfs_test_opt(root, NODATACOW))
btrfs_info(root->fs_info, "setting datacow");
btrfs_clear_opt(info->mount_opt, NODATACOW);
break;
case Opt_compress_force:
case Opt_compress_force_type:
compress_force = true;