crypto: cast6 - add x86_64/avx assembler implementation

This patch adds a x86_64/avx assembler implementation of the Cast6 block
cipher. The implementation processes eight blocks in parallel (two 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)

cast6-avx-x86_64 vs. cast6-generic
128bit key:                                             (lrw:256bit)    (xts:256bit)
size    ecb-enc ecb-dec cbc-enc cbc-dec ctr-enc ctr-dec lrw-enc lrw-dec xts-enc xts-dec
16B     0.97x   1.00x   1.01x   1.01x   0.99x   0.97x   0.98x   1.01x   0.96x   0.98x
64B     0.98x   0.99x   1.02x   1.01x   0.99x   1.00x   1.01x   0.99x   1.00x   0.99x
256B    1.77x   1.84x   0.99x   1.85x   1.77x   1.77x   1.70x   1.74x   1.69x   1.72x
1024B   1.93x   1.95x   0.99x   1.96x   1.93x   1.93x   1.84x   1.85x   1.89x   1.87x
8192B   1.91x   1.95x   0.99x   1.97x   1.95x   1.91x   1.86x   1.87x   1.93x   1.90x

256bit key:                                             (lrw:384bit)    (xts:512bit)
size    ecb-enc ecb-dec cbc-enc cbc-dec ctr-enc ctr-dec lrw-enc lrw-dec xts-enc xts-dec
16B     0.97x   0.99x   1.02x   1.01x   0.98x   0.99x   1.00x   1.00x   0.98x   0.98x
64B     0.98x   0.99x   1.01x   1.00x   1.00x   1.00x   1.01x   1.01x   0.97x   1.00x
256B    1.77x   1.83x   1.00x   1.86x   1.79x   1.78x   1.70x   1.76x   1.71x   1.69x
1024B   1.92x   1.95x   0.99x   1.96x   1.93x   1.93x   1.83x   1.86x   1.89x   1.87x
8192B   1.94x   1.95x   0.99x   1.97x   1.95x   1.95x   1.87x   1.87x   1.93x   1.91x

Signed-off-by: Johannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 17 insertions, 0 deletions

diff --git a/crypto/Kconfig b/crypto/Kconfig
index cda97fcaa822..fe8ed62efe2f 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -713,6 +713,23 @@ config CRYPTO_CAST6
           The CAST6 encryption algorithm (synonymous with CAST-256) is
           described in RFC2612.
 
+config CRYPTO_CAST6_AVX_X86_64
+        tristate "CAST6 (CAST-256) cipher algorithm (x86_64/AVX)"
+        depends on X86 && 64BIT
+        select CRYPTO_ALGAPI
+        select CRYPTO_CRYPTD
+        select CRYPTO_ABLK_HELPER_X86
+        select CRYPTO_GLUE_HELPER_X86
+        select CRYPTO_CAST6
+        select CRYPTO_LRW
+        select CRYPTO_XTS
+        help
+          The CAST6 encryption algorithm (synonymous with CAST-256) is
+          described in RFC2612.
+
+          This module provides the Cast6 cipher algorithm that processes
+          eight blocks parallel using the AVX instruction set.
+
 config CRYPTO_DES
         tristate "DES and Triple DES EDE cipher algorithms"
         select CRYPTO_ALGAPI