On Wed, Jan 30, 2019 at 6:30 AM Amir Goldstein <amir73il@xxxxxxxxx> wrote: > generic_remap_file_range_prep() does not require that source > file is not immutable. Does XFS? I don't know if "immutable" > has ever been defined w.r.t file layout on disk. has it? > I recon btrfs re-balancing would not stop at migrating "immutable" > file blocks would it? chattr +i does not pin the file to a particular physical location on a device or even on a particular device, at least on Btrfs. A balance operation, including device replace, or device add+remove, or changing the raid profile, isn't inhibited - such operations happen at the block group level, somewhat similar to LVM pvmove. A directory containing an immutable file cannot be deleted until immutable flag is unset; but a subvolume containing an immutable file is deleted without complaint when using 'btrfs sub del'. I'm pretty sure that's expected. Further, looks like now 'rmdir' and 'rm -rf' will remove a subvolume; but in the case of it containing an immutable file, 'rm -rf' fails just as if it were a directory even though 'btrfs sub del' succeeds. -- Chris Murphy
