Update the fscrypt documentation file for inline encryption support. Signed-off-by: Satya Tangirala <satyat@xxxxxxxxxx> --- Documentation/filesystems/fscrypt.rst | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst index f5d8b0303ddf..f3d87a1a0a7f 100644 --- a/Documentation/filesystems/fscrypt.rst +++ b/Documentation/filesystems/fscrypt.rst @@ -1204,6 +1204,18 @@ buffer. Some filesystems, such as UBIFS, already use temporary buffers regardless of encryption. Other filesystems, such as ext4 and F2FS, have to allocate bounce pages specially for encryption. +Fscrypt is also able to use inline encryption hardware instead of the +kernel crypto API for en/decryption of file contents. When possible, and +if directed to do so (by specifying the 'inlinecrypt' mount option for +an ext4/F2FS filesystem), it adds encryption contexts to bios and +uses blk-crypto to perform the en/decryption instead of making use +of the above read/write path changes. Of course, even if directed to make +use of inline encryption, fscrypt will only be able to do so if either +hardware inline encryption support is available for the selected encryption +algorithm or CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK is selected. If neither +is the case, fscrypt will fall back to using the above mentioned read/write +path changes for en/decryption. + Filename hashing and encoding ----------------------------- @@ -1250,7 +1262,9 @@ Tests To test fscrypt, use xfstests, which is Linux's de facto standard filesystem test suite. First, run all the tests in the "encrypt" -group on the relevant filesystem(s). For example, to test ext4 and +group on the relevant filesystem(s). One can also run the tests +with the 'inlinecrypt' mount option to test the implementation for +inline encryption support. For example, to test ext4 and f2fs encryption using `kvm-xfstests <https://github.com/tytso/xfstests-bld/blob/master/Documentation/kvm-quickstart.md>`_:: -- 2.28.0.rc0.105.gf9edc3c819-goog
