Add datacow mount option to enable copy-on-write with remount option. Signed-off-by: Qu Wenruo <quwen...@cn.fujitsu.com> --- changelog: v2: Add datacow mount option. --- Documentation/filesystems/btrfs.txt | 5 +++-- fs/btrfs/super.c | 8 +++++++- 2 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt index 6f2de1b..48c1833 100644 --- a/Documentation/filesystems/btrfs.txt +++ b/Documentation/filesystems/btrfs.txt @@ -159,9 +159,10 @@ Options with (*) are default options and will not show in the mount options. (non-battery-backed) write-back cache, this 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 a5c25fd..cb4c90d 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -325,7 +325,7 @@ enum { Opt_check_integrity_print_mask, Opt_fatal_errors, Opt_rescan_uuid_tree, Opt_commit_interval, Opt_barrier, Opt_nodefrag, Opt_nocheck_integrity, Opt_nodiscard, Opt_noenospc_debug, Opt_noflushoncommit, - Opt_noinode_cache, Opt_acl, + Opt_noinode_cache, Opt_acl, Opt_datacow, Opt_err, }; @@ -336,6 +336,7 @@ 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"}, @@ -449,6 +450,11 @@ 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; -- 1.8.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html