As we will exhaust the first 32 bits of AT_HWCAP let's start
exposing AT_HWCAP2 to userspace to give us up to 64 caps.
Whilst it's possible to use the remaining 32 bits of AT_HWCAP, we
prefer to expand into AT_HWCAP2 in order to provide a consistent
view to userspace between ILP32 and LP64. However internal to the
kernel we prefer to continue to use the full space of elf_hwcap.
To reduce complexity and allow for future expansion, we now
represent hwcaps in the kernel as ordinals and use a
KERNEL_HWCAP_ prefix. This allows us to support automatic feature
based module loading for all our hwcaps.
We introduce cpu_set_feature to set hwcaps which complements the
existing cpu_have_feature helper. These helpers allow us to clean
up existing direct uses of elf_hwcap and reduce any future effort
required to move beyond 64 caps.
For convenience we also introduce cpu_{have,set}_named_feature which
makes use of the cpu_feature macro to allow providing a hwcap name
without a {KERNEL_}HWCAP_ prefix.
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
[will: use const_ilog2() and tweak documentation]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Commit b73b7ac0a7 ("crypto: sha256_generic - add cra_priority") gave
sha256-generic and sha224-generic a cra_priority of 100, to match the
convention for generic implementations. But sha256-arm64 and
sha224-arm64 also have priority 100, so their order relative to the
generic implementations became ambiguous.
Therefore, increase their priority to 125 so that they have higher
priority than the generic implementations but lower priority than the
NEON implementations which have priority 150.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Many shash algorithms set .cra_flags = CRYPTO_ALG_TYPE_SHASH. But this
is redundant with the C structure type ('struct shash_alg'), and
crypto_register_shash() already sets the type flag automatically,
clearing any type flag that was already there. Apparently the useless
assignment has just been copy+pasted around.
So, remove the useless assignment from all the shash algorithms.
This patch shouldn't change any actual behavior.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tweak the SHA256 update routines to invoke the SHA256 block transform
block by block, to avoid excessive scheduling delays caused by the
NEON algorithm running with preemption disabled.
Also, remove a stale comment which no longer applies now that kernel
mode NEON is actually disallowed in some contexts.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The arm64 kernel will shortly disallow nested kernel mode NEON, so
add a fallback to scalar code that can be invoked in that case.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This integrates both the accelerated scalar and the NEON implementations
of SHA-224/256 as well as SHA-384/512 from the OpenSSL project.
Relative performance compared to the respective generic C versions:
| SHA256-scalar | SHA256-NEON* | SHA512 |
------------+-----------------+--------------+----------+
Cortex-A53 | 1.63x | 1.63x | 2.34x |
Cortex-A57 | 1.43x | 1.59x | 1.95x |
Cortex-A73 | 1.26x | 1.56x | ? |
The core crypto code was authored by Andy Polyakov of the OpenSSL
project, in collaboration with whom the upstream code was adapted so
that this module can be built from the same version of sha512-armv8.pl.
The version in this patch was taken from OpenSSL commit 32bbb62ea634
("sha/asm/sha512-armv8.pl: fix big-endian support in __KERNEL__ case.")
* The core SHA algorithm is fundamentally sequential, but there is a
secondary transformation involved, called the schedule update, which
can be performed independently. The NEON version of SHA-224/SHA-256
only implements this part of the algorithm using NEON instructions,
the sequential part is always done using scalar instructions.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Andrew Murray