This patch series adds support for direct I/O with fscrypt using blk-crypto. It has been rebased on fscrypt/master. Patch 1 adds two functions to fscrypt that need to be called to determine if direct I/O is supported for a request. Patches 2 and 3 wire up direct-io and iomap respectively with the functions introduced in Patch 1 and set bio crypt contexts on bios when appropriate by calling into fscrypt. Patches 4 and 5 allow ext4 and f2fs direct I/O to support fscrypt without falling back to buffered I/O. Patches 6 and 7 update the fscrypt documentation for inline encryption support and direct I/O. The documentation now notes the required conditions for inline encryption and direct I/O on encrypted files. This patch series was tested by running xfstests with test_dummy_encryption with and without the 'inlinecrypt' mount option, and there were no meaningful regressions. One regression was for generic/587 on ext4, but that test isn't compatible with test_dummy_encryption in the first place, and the test "incorrectly" passes without the 'inlinecrypt' mount option - a patch will be sent out to exclude that test when test_dummy_encryption is turned on with ext4 (like the other quota related tests that use user visible quota files). The other regression was for generic/252 on ext4, which does direct I/O with a buffer aligned to the block device's blocksize, but not necessarily aligned to the filesystem's block size, which direct I/O with fscrypt requires. Changes v3 => v4: - Fix bug in iomap_dio_bio_actor() where fscrypt_limit_io_pages() was being called too early (thanks Eric!) - Improve comments and fix formatting in documentation - iomap_dio_zero() is only called to zero out partial blocks, but direct I/O is only supported on encrypted files when I/O is blocksize aligned, so it doesn't need to set encryption contexts on bios. Replace setting the encryption context with a WARN_ON(). (Eric) Changes v2 => v3: - add changelog to coverletter Changes v1 => v2: - Fix bug in f2fs caused by replacing f2fs_post_read_required() with !fscrypt_dio_supported() since the latter doesn't check for compressed inodes unlike the former. - Add patches 6 and 7 for fscrypt documentation - cleanups and comments Eric Biggers (5): fscrypt: Add functions for direct I/O support direct-io: add support for fscrypt using blk-crypto iomap: support direct I/O with fscrypt using blk-crypto ext4: support direct I/O with fscrypt using blk-crypto f2fs: support direct I/O with fscrypt using blk-crypto Satya Tangirala (2): fscrypt: document inline encryption support fscrypt: update documentation for direct I/O support Documentation/filesystems/fscrypt.rst | 36 +++++++++++- fs/crypto/crypto.c | 8 +++ fs/crypto/inline_crypt.c | 82 +++++++++++++++++++++++++++ fs/direct-io.c | 15 ++++- fs/ext4/file.c | 10 ++-- fs/f2fs/f2fs.h | 6 +- fs/iomap/direct-io.c | 12 +++- include/linux/fscrypt.h | 19 +++++++ 8 files changed, 178 insertions(+), 10 deletions(-) -- 2.28.0.rc0.105.gf9edc3c819-goog
