On Thu, Oct 24, 2019 at 02:54:37PM -0700, Eric Biggers wrote: > From: Eric Biggers <ebiggers@xxxxxxxxxx> > > IV_INO_LBLK_64 encryption policies have special requirements from the > filesystem beyond those of the existing encryption policies: > > - Inode numbers must never change, even if the filesystem is resized. > - Inode numbers must be <= 32 bits. > - File logical block numbers must be <= 32 bits. > > ext4 has 32-bit inode and file logical block numbers. However, > resize2fs can re-number inodes when shrinking an ext4 filesystem. > > However, typically the people who would want to use this format don't > care about filesystem shrinking. They'd be fine with a solution that > just prevents the filesystem from being shrunk. > > Therefore, add a new feature flag EXT4_FEATURE_COMPAT_STABLE_INODES that > will do exactly that. Then wire up the fscrypt_operations to expose > this flag to fs/crypto/, so that it allows IV_INO_LBLK_64 policies when > this flag is set. > > Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> LGTM Acked-by: Theodore Ts'o <tytso@xxxxxxx> - Ted
