Re: [PATCH v2 2/3] ext4: add support for IV_INO_LBLK_64 encryption policies
From: "Theodore Y. Ts'o" <tytso@mit.edu>
Date: 2019-11-06 03:26:42
Also in:
linux-f2fs-devel, linux-fscrypt, linux-fsdevel
On Thu, Oct 24, 2019 at 02:54:37PM -0700, Eric Biggers wrote:
From: Eric Biggers <redacted> 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 <redacted>
LGTM Acked-by: Theodore Ts'o <tytso@mit.edu> - Ted