path: root/Documentation
diff options
authorDavid Sterba <>2017-11-07 19:17:41 +0100
committerDavid Sterba <>2017-11-14 15:59:00 +0100
commita0abb062181ad97bffc5011fba6920baeee5152e (patch)
tree4cf43fb4df5904728876bb0950f37b7e28a321fc /Documentation
parentc9fa9355f39683fe6e294d16745427a6e42ba45a (diff)
btrfs-progs: docs: add note about mount option applicability
Copied from . Signed-off-by: David Sterba <>
Diffstat (limited to 'Documentation')
1 files changed, 7 insertions, 0 deletions
diff --git a/Documentation/btrfs-man5.asciidoc b/Documentation/btrfs-man5.asciidoc
index bd005331..dd436cd1 100644
--- a/Documentation/btrfs-man5.asciidoc
+++ b/Documentation/btrfs-man5.asciidoc
@@ -26,6 +26,13 @@ This section describes mount options specific to BTRFS. For the generic mount
options please refer to `mount`(8) manpage. The options are sorted alphabetically
(discarding the 'no' prefix).
+NOTE: most mount options apply to the whole filesystem and only options in the
+first mounted subvolume will take effect. This is due to lack of implementation
+and may change in the future. This means that (for example) you can't set
+per-subvolume 'nodatacow', 'nodatasum', or 'compress' using mount options. This
+should eventually be fixed, but it has proved to be difficult to implement
+correctly within the Linux VFS framework.
(default: on)