diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt index 79c08f368ace..bbd1f0f57ce9 100644 --- a/Documentation/filesystems/btrfs.txt +++ b/Documentation/filesystems/btrfs.txt @@ -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. diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 76eecd13db19..6567865a2504 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -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;