linux/arch/x86/crypto/sha256_ssse3_glue.c
Ingo Molnar 70d51eb65d x86/fpu, crypto x86/sha256_ssse3: Simplify the sha256_ssse3_mod_init() xfeature checks
Use the new 'cpu_has_xfeatures()' function to query AVX CPU support.

This has the following advantages to the driver:

 - Decouples the driver from FPU internals: it's now only using <asm/fpu/api.h>.

 - Removes detection complexity from the driver, no more raw XGETBV instruction

 - Shrinks the code a bit.

 - Standardizes feature name error message printouts across drivers

There are also advantages to the x86 FPU code: once all drivers
are decoupled from internals we can move them out of common
headers and we'll also be able to remove xcr.h.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:57 +02:00

192 lines
5.2 KiB
C

/*
* Cryptographic API.
*
* Glue code for the SHA256 Secure Hash Algorithm assembler
* implementation using supplemental SSE3 / AVX / AVX2 instructions.
*
* This file is based on sha256_generic.c
*
* Copyright (C) 2013 Intel Corporation.
*
* Author:
* Tim Chen <tim.c.chen@linux.intel.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <crypto/internal/hash.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/cryptohash.h>
#include <linux/types.h>
#include <crypto/sha.h>
#include <crypto/sha256_base.h>
#include <asm/fpu/api.h>
#include <linux/string.h>
asmlinkage void sha256_transform_ssse3(u32 *digest, const char *data,
u64 rounds);
#ifdef CONFIG_AS_AVX
asmlinkage void sha256_transform_avx(u32 *digest, const char *data,
u64 rounds);
#endif
#ifdef CONFIG_AS_AVX2
asmlinkage void sha256_transform_rorx(u32 *digest, const char *data,
u64 rounds);
#endif
static void (*sha256_transform_asm)(u32 *, const char *, u64);
static int sha256_ssse3_update(struct shash_desc *desc, const u8 *data,
unsigned int len)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
if (!irq_fpu_usable() ||
(sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
return crypto_sha256_update(desc, data, len);
/* make sure casting to sha256_block_fn() is safe */
BUILD_BUG_ON(offsetof(struct sha256_state, state) != 0);
kernel_fpu_begin();
sha256_base_do_update(desc, data, len,
(sha256_block_fn *)sha256_transform_asm);
kernel_fpu_end();
return 0;
}
static int sha256_ssse3_finup(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out)
{
if (!irq_fpu_usable())
return crypto_sha256_finup(desc, data, len, out);
kernel_fpu_begin();
if (len)
sha256_base_do_update(desc, data, len,
(sha256_block_fn *)sha256_transform_asm);
sha256_base_do_finalize(desc, (sha256_block_fn *)sha256_transform_asm);
kernel_fpu_end();
return sha256_base_finish(desc, out);
}
/* Add padding and return the message digest. */
static int sha256_ssse3_final(struct shash_desc *desc, u8 *out)
{
return sha256_ssse3_finup(desc, NULL, 0, out);
}
static struct shash_alg algs[] = { {
.digestsize = SHA256_DIGEST_SIZE,
.init = sha256_base_init,
.update = sha256_ssse3_update,
.final = sha256_ssse3_final,
.finup = sha256_ssse3_finup,
.descsize = sizeof(struct sha256_state),
.base = {
.cra_name = "sha256",
.cra_driver_name = "sha256-ssse3",
.cra_priority = 150,
.cra_flags = CRYPTO_ALG_TYPE_SHASH,
.cra_blocksize = SHA256_BLOCK_SIZE,
.cra_module = THIS_MODULE,
}
}, {
.digestsize = SHA224_DIGEST_SIZE,
.init = sha224_base_init,
.update = sha256_ssse3_update,
.final = sha256_ssse3_final,
.finup = sha256_ssse3_finup,
.descsize = sizeof(struct sha256_state),
.base = {
.cra_name = "sha224",
.cra_driver_name = "sha224-ssse3",
.cra_priority = 150,
.cra_flags = CRYPTO_ALG_TYPE_SHASH,
.cra_blocksize = SHA224_BLOCK_SIZE,
.cra_module = THIS_MODULE,
}
} };
#ifdef CONFIG_AS_AVX
static bool __init avx_usable(void)
{
if (!cpu_has_xfeatures(XSTATE_SSE | XSTATE_YMM, NULL)) {
if (cpu_has_avx)
pr_info("AVX detected but unusable.\n");
return false;
}
return true;
}
#endif
static int __init sha256_ssse3_mod_init(void)
{
/* test for SSSE3 first */
if (cpu_has_ssse3)
sha256_transform_asm = sha256_transform_ssse3;
#ifdef CONFIG_AS_AVX
/* allow AVX to override SSSE3, it's a little faster */
if (avx_usable()) {
#ifdef CONFIG_AS_AVX2
if (boot_cpu_has(X86_FEATURE_AVX2) && boot_cpu_has(X86_FEATURE_BMI2))
sha256_transform_asm = sha256_transform_rorx;
else
#endif
sha256_transform_asm = sha256_transform_avx;
}
#endif
if (sha256_transform_asm) {
#ifdef CONFIG_AS_AVX
if (sha256_transform_asm == sha256_transform_avx)
pr_info("Using AVX optimized SHA-256 implementation\n");
#ifdef CONFIG_AS_AVX2
else if (sha256_transform_asm == sha256_transform_rorx)
pr_info("Using AVX2 optimized SHA-256 implementation\n");
#endif
else
#endif
pr_info("Using SSSE3 optimized SHA-256 implementation\n");
return crypto_register_shashes(algs, ARRAY_SIZE(algs));
}
pr_info("Neither AVX nor SSSE3 is available/usable.\n");
return -ENODEV;
}
static void __exit sha256_ssse3_mod_fini(void)
{
crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
}
module_init(sha256_ssse3_mod_init);
module_exit(sha256_ssse3_mod_fini);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("SHA256 Secure Hash Algorithm, Supplemental SSE3 accelerated");
MODULE_ALIAS_CRYPTO("sha256");
MODULE_ALIAS_CRYPTO("sha224");