On Fri, Mar 05, 2021 at 11:26:29AM -0800, Boris Burkov wrote: > The tree checker currently rejects unrecognized flags when it reads > btrfs_inode_item. Practically, this means that adding a new flag makes > the change backwards incompatible if the flag is ever set on a file. > > Take up one of the 4 reserved u64 fields in the btrfs_inode_item as a > new "compat_flags". These flags are zero on inode creation in btrfs and > mkfs and are ignored by an older kernel, so it should be safe to use > them in this way. > > Signed-off-by: Boris Burkov <bo...@bur.io>
How does this interact with the RO_COMPAT filesystem flag which is also being added? - Eric
