Add an implementation of sha256_finup_2x_arch() for arm64. It
interleaves the computation of two SHA-256 hashes using the ARMv8
SHA-256 instructions. dm-verity and fs-verity will take advantage of
this for greatly improved performance on capable CPUs.
This increases the throughput of SHA-256 hashing 4096-byte messages by
the following amounts on the following CPUs:
ARM Cortex-X1: 70%
ARM Cortex-X3: 68%
ARM Cortex-A76: 65%
ARM Cortex-A715: 43%
ARM Cortex-A510: 25%
ARM Cortex-A55: 8%
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250915160819.140019-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Move the contents of arch/arm64/lib/crypto/ into lib/crypto/arm64/.
The new code organization makes a lot more sense for how this code
actually works and is developed. In particular, it makes it possible to
build each algorithm as a single module, with better inlining and dead
code elimination. For a more detailed explanation, see the patchset
which did this for the CRC library code:
https://lore.kernel.org/r/20250607200454.73587-1-ebiggers@kernel.org/.
Also see the patchset which did this for SHA-512:
https://lore.kernel.org/linux-crypto/20250616014019.415791-1-ebiggers@kernel.org/
This is just a preparatory commit, which does the move to get the files
into their new location but keeps them building the same way as before.
Later commits will make the actual improvements to the way the
arch-optimized code is integrated for each algorithm.
Add a gitignore entry for the removed directory arch/arm64/lib/crypto/
so that people don't accidentally commit leftover generated files.
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Link: https://lore.kernel.org/r/20250619191908.134235-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
