Re: [PATCH 02/13] crypto: arm/sha256 - implement library instead of shash

[Ard Biesheuvel <ardb@kernel.org>]

On Sat, 26 Apr 2025 at 08:51, Eric Biggers <ebiggers@kernel.org> wrote:
>
> From: Eric Biggers <ebiggers@google.com>
>
> Instead of providing crypto_shash algorithms for the arch-optimized
> SHA-256 code, instead implement the SHA-256 library.  This is much
> simpler, it makes the SHA-256 library functions be arch-optimized, and
> it fixes the longstanding issue where the arch-optimized SHA-256 was
> disabled by default.  SHA-256 still remains available through
> crypto_shash, but individual architectures no longer need to handle it.
>
> To merge the scalar, NEON, and CE code all into one module cleanly, add
> !CPU_V7M as a direct dependency of the CE code.  Previously, !CPU_V7M
> was only a direct dependency of the scalar and NEON code.  The result is
> still the same because CPU_V7M implies !KERNEL_MODE_NEON, so !CPU_V7M
> was already an indirect dependency of the CE code.
>
> To match sha256_blocks_arch(), change the type of the nblocks parameter
> of the assembly functions from int to size_t.  The assembly functions
> actually already treated it as size_t.
>
> While renaming the assembly files, also fix the naming quirk where
> "sha2" meant sha256.  (SHA-512 is also part of SHA-2.)
>
> Signed-off-by: Eric Biggers <ebiggers@google.com>
> ---
>  arch/arm/configs/exynos_defconfig             |   1 -
>  arch/arm/configs/milbeaut_m10v_defconfig      |   1 -
>  arch/arm/configs/multi_v7_defconfig           |   1 -
>  arch/arm/configs/omap2plus_defconfig          |   1 -
>  arch/arm/configs/pxa_defconfig                |   1 -
>  arch/arm/crypto/Kconfig                       |  21 ----
>  arch/arm/crypto/Makefile                      |   8 +-
>  arch/arm/crypto/sha2-ce-glue.c                |  87 --------------
>  arch/arm/crypto/sha256_glue.c                 | 107 ------------------
>  arch/arm/crypto/sha256_glue.h                 |   9 --
>  arch/arm/crypto/sha256_neon_glue.c            |  75 ------------
>  arch/arm/lib/crypto/.gitignore                |   1 +
>  arch/arm/lib/crypto/Kconfig                   |   6 +
>  arch/arm/lib/crypto/Makefile                  |   8 +-
>  arch/arm/{ => lib}/crypto/sha256-armv4.pl     |   0
>  .../sha2-ce-core.S => lib/crypto/sha256-ce.S} |  10 +-
>  arch/arm/lib/crypto/sha256.c                  |  64 +++++++++++
>  17 files changed, 84 insertions(+), 317 deletions(-)
>  delete mode 100644 arch/arm/crypto/sha2-ce-glue.c
>  delete mode 100644 arch/arm/crypto/sha256_glue.c
>  delete mode 100644 arch/arm/crypto/sha256_glue.h
>  delete mode 100644 arch/arm/crypto/sha256_neon_glue.c
>  rename arch/arm/{ => lib}/crypto/sha256-armv4.pl (100%)
>  rename arch/arm/{crypto/sha2-ce-core.S => lib/crypto/sha256-ce.S} (91%)
>  create mode 100644 arch/arm/lib/crypto/sha256.c
>

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>