[PATCH v2 6/9] crypto: x86/cast - stop using the SIMD helper

Eric Biggers
2025-04-02T00:24:45Z

From: Eric Biggers <ebiggers@google.com>

Stop wrapping skcipher and aead algorithms with the crypto SIMD helper
(crypto/simd.c). The only purpose of doing so was to work around x86
not always supporting kernel-mode FPU in softirqs. Specifically, if a
hardirq interrupted a task context kernel-mode FPU section and then a
softirqs were run at the end of that hardirq, those softirqs could not
use kernel-mode FPU. This has now been fixed. In combination with the
fact that the skcipher and aead APIs only support task and softirq
contexts, these can now just use kernel-mode FPU unconditionally on x86.

This simplifies the code and improves performance.

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
arch/x86/crypto/Kconfig | 2 --
arch/x86/crypto/cast5_avx_glue.c | 21 +++++++--------------
arch/x86/crypto/cast6_avx_glue.c | 20 ++++++--------------
3 files changed, 13 insertions(+), 30 deletions(-)

diff --git a/arch/x86/crypto/Kconfig b/arch/x86/crypto/Kconfig
index de927df89ccf1..55800d1ce668e 100644
--- a/arch/x86/crypto/Kconfig
+++ b/arch/x86/crypto/Kconfig
@@ -86,11 +86,10 @@ config CRYPTO_CAST5_AVX_X86_64
tristate "Ciphers: CAST5 with modes: ECB, CBC (AVX)"
depends on X86 && 64BIT
select CRYPTO_SKCIPHER
select CRYPTO_CAST5
select CRYPTO_CAST_COMMON
- select CRYPTO_SIMD
imply CRYPTO_CTR
help
Length-preserving ciphers: CAST5 (CAST-128) cipher algorithm
(RFC2144) with ECB and CBC modes

@@ -103,11 +102,10 @@ config CRYPTO_CAST6_AVX_X86_64
tristate "Ciphers: CAST6 with modes: ECB, CBC (AVX)"
depends on X86 && 64BIT
select CRYPTO_SKCIPHER
select CRYPTO_CAST6
select CRYPTO_CAST_COMMON
- select CRYPTO_SIMD
imply CRYPTO_XTS
imply CRYPTO_CTR
help
Length-preserving ciphers: CAST6 (CAST-256) cipher algorithm
(RFC2612) with ECB and CBC modes
diff --git a/arch/x86/crypto/cast5_avx_glue.c b/arch/x86/crypto/cast5_avx_glue.c
index 3976a87f92ad5..3aca04d43b34a 100644
--- a/arch/x86/crypto/cast5_avx_glue.c
+++ b/arch/x86/crypto/cast5_avx_glue.c
@@ -6,11 +6,10 @@
* <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
*/

#include <crypto/algapi.h>
#include <crypto/cast5.h>
-#include <crypto/internal/simd.h>
#include <linux/crypto.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/types.h>

@@ -62,27 +61,25 @@ static int cbc_decrypt(struct skcipher_request *req)
CBC_WALK_END();
}

static struct skcipher_alg cast5_algs[] = {
{
- .base.cra_name = "__ecb(cast5)",
- .base.cra_driver_name = "__ecb-cast5-avx",
+ .base.cra_name = "ecb(cast5)",
+ .base.cra_driver_name = "ecb-cast5-avx",
.base.cra_priority = 200,
- .base.cra_flags = CRYPTO_ALG_INTERNAL,
.base.cra_blocksize = CAST5_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct cast5_ctx),
.base.cra_module = THIS_MODULE,
.min_keysize = CAST5_MIN_KEY_SIZE,
.max_keysize = CAST5_MAX_KEY_SIZE,
.setkey = cast5_setkey_skcipher,
.encrypt = ecb_encrypt,
.decrypt = ecb_decrypt,
}, {
- .base.cra_name = "__cbc(cast5)",
- .base.cra_driver_name = "__cbc-cast5-avx",
+ .base.cra_name = "cbc(cast5)",
+ .base.cra_driver_name = "cbc-cast5-avx",
.base.cra_priority = 200,
- .base.cra_flags = CRYPTO_ALG_INTERNAL,
.base.cra_blocksize = CAST5_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct cast5_ctx),
.base.cra_module = THIS_MODULE,
.min_keysize = CAST5_MIN_KEY_SIZE,
.max_keysize = CAST5_MAX_KEY_SIZE,
@@ -91,31 +88,27 @@ static struct skcipher_alg cast5_algs[] = {
.encrypt = cbc_encrypt,
.decrypt = cbc_decrypt,
}
};

-static struct simd_skcipher_alg *cast5_simd_algs[ARRAY_SIZE(cast5_algs)];
-
static int __init cast5_init(void)
{
const char *feature_name;

if (!cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM,
&feature_name)) {
pr_info("CPU feature '%s' is not supported.\n", feature_name);
return -ENODEV;
}

- return simd_register_skciphers_compat(cast5_algs,
- ARRAY_SIZE(cast5_algs),
- cast5_simd_algs);
+ return crypto_register_skciphers(cast5_algs,
+ ARRAY_SIZE(cast5_algs));
}

static void __exit cast5_exit(void)
{
- simd_unregister_skciphers(cast5_algs, ARRAY_SIZE(cast5_algs),
- cast5_simd_algs);
+ crypto_unregister_skciphers(cast5_algs, ARRAY_SIZE(cast5_algs));
}

module_init(cast5_init);
module_exit(cast5_exit);

diff --git a/arch/x86/crypto/cast6_avx_glue.c b/arch/x86/crypto/cast6_avx_glue.c
index 7e2aea3723490..c4dd28c303036 100644
--- a/arch/x86/crypto/cast6_avx_glue.c
+++ b/arch/x86/crypto/cast6_avx_glue.c
@@ -12,11 +12,10 @@
#include <linux/types.h>
#include <linux/crypto.h>
#include <linux/err.h>
#include <crypto/algapi.h>
#include <crypto/cast6.h>
-#include <crypto/internal/simd.h>

#include "ecb_cbc_helpers.h"

#define CAST6_PARALLEL_BLOCKS 8

@@ -62,27 +61,25 @@ static int cbc_decrypt(struct skcipher_request *req)
CBC_WALK_END();
}

static struct skcipher_alg cast6_algs[] = {
{
- .base.cra_name = "__ecb(cast6)",
- .base.cra_driver_name = "__ecb-cast6-avx",
+ .base.cra_name = "ecb(cast6)",
+ .base.cra_driver_name = "ecb-cast6-avx",
.base.cra_priority = 200,
- .base.cra_flags = CRYPTO_ALG_INTERNAL,
.base.cra_blocksize = CAST6_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct cast6_ctx),
.base.cra_module = THIS_MODULE,
.min_keysize = CAST6_MIN_KEY_SIZE,
.max_keysize = CAST6_MAX_KEY_SIZE,
.setkey = cast6_setkey_skcipher,
.encrypt = ecb_encrypt,
.decrypt = ecb_decrypt,
}, {
- .base.cra_name = "__cbc(cast6)",
- .base.cra_driver_name = "__cbc-cast6-avx",
+ .base.cra_name = "cbc(cast6)",
+ .base.cra_driver_name = "cbc-cast6-avx",
.base.cra_priority = 200,
- .base.cra_flags = CRYPTO_ALG_INTERNAL,
.base.cra_blocksize = CAST6_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct cast6_ctx),
.base.cra_module = THIS_MODULE,
.min_keysize = CAST6_MIN_KEY_SIZE,
.max_keysize = CAST6_MAX_KEY_SIZE,
@@ -91,31 +88,26 @@ static struct skcipher_alg cast6_algs[] = {
.encrypt = cbc_encrypt,
.decrypt = cbc_decrypt,
},
};

-static struct simd_skcipher_alg *cast6_simd_algs[ARRAY_SIZE(cast6_algs)];
-
static int __init cast6_init(void)
{
const char *feature_name;

if (!cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM,
&feature_name)) {
pr_info("CPU feature '%s' is not supported.\n", feature_name);
return -ENODEV;
}

- return simd_register_skciphers_compat(cast6_algs,
- ARRAY_SIZE(cast6_algs),
- cast6_simd_algs);
+ return crypto_register_skciphers(cast6_algs, ARRAY_SIZE(cast6_algs));
}

static void __exit cast6_exit(void)
{
- simd_unregister_skciphers(cast6_algs, ARRAY_SIZE(cast6_algs),
- cast6_simd_algs);
+ crypto_unregister_skciphers(cast6_algs, ARRAY_SIZE(cast6_algs));
}

module_init(cast6_init);
module_exit(cast6_exit);

--
2.49.0