Patch adds AVX2/x86-64 implementation of Blowfish cipher, requiring 32 parallel
blocks for input (256 bytes). Table look-ups are performed using vpgatherdd
instruction directly from vector registers and thus should be faster than
earlier implementations.
Signed-off-by: NJussi Kivilinna <jussi.kivilinna@iki.fi>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Introduce new assembler functions to avoid use temporary stack buffers in glue
code. This also allows use of vector instructions for xoring output in CTR and
CBC modes and construction of IVs for CTR mode.

ECB mode sees ~0.5% decrease in speed because added one extra function
call. CBC mode decryption and CTR mode benefit from vector operations
and gain ~5%.
Signed-off-by: NJussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

cast5/avx incorrectly XORs new IV over old IV at end of CBC encryption
function when it should store. This causes CBC encryption to give
incorrect output on multi-page encryption requests.
Signed-off-by: NJussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch adds a x86_64/avx assembler implementation of the Cast5 block
cipher. The implementation processes sixteen blocks in parallel (four 4 block
chunk AVX operations). The table-lookups are done in general-purpose registers.
For small blocksizes the functions from the generic module are called. A good
performance increase is provided for blocksizes greater or equal to 128B.

Patch has been tested with tcrypt and automated filesystem tests.

Tcrypt benchmark results:

Intel Core i5-2500 CPU (fam:6, model:42, step:7)

cast5-avx-x86_64 vs. cast5-generic
64bit key:
size    ecb-enc ecb-dec cbc-enc cbc-dec ctr-enc ctr-dec
16B     0.99x   0.99x   1.00x   1.00x   1.02x   1.01x
64B     1.00x   1.00x   0.98x   1.00x   1.01x   1.02x
256B    2.03x   2.01x   0.95x   2.11x   2.12x   2.13x
1024B   2.30x   2.24x   0.95x   2.29x   2.35x   2.35x
8192B   2.31x   2.27x   0.95x   2.31x   2.39x   2.39x

128bit key:
size    ecb-enc ecb-dec cbc-enc cbc-dec ctr-enc ctr-dec
16B     0.99x   0.99x   1.00x   1.00x   1.01x   1.01x
64B     1.00x   1.00x   0.98x   1.01x   1.02x   1.01x
256B    2.17x   2.13x   0.96x   2.19x   2.19x   2.19x
1024B   2.29x   2.32x   0.95x   2.34x   2.37x   2.38x
8192B   2.35x   2.32x   0.95x   2.35x   2.39x   2.39x
Signed-off-by: NJohannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>