crypto: arm64/crc32 - remove PMULL based CRC32 driver

Now that the scalar fallbacks have been moved out of this driver into
the core crc32()/crc32c() routines, we are left with a CRC32 crypto API
driver for arm64 that is based only on 64x64 polynomial multiplication,
which is an optional instruction in the ARMv8 architecture, and is less
and less likely to be available on cores that do not also implement the
CRC32 instructions, given that those are mandatory in the architecture
as of ARMv8.1.

Since the scalar instructions do not require the special handling that
SIMD instructions do, and since they turn out to be considerably faster
on some cores (Cortex-A53) as well, there is really no point in keeping
this code around so let's just remove it.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 0 insertions, 244 deletions

diff --git a/arch/arm64/crypto/crc32-ce-glue.c b/arch/arm64/crypto/crc32-ce-glue.c
deleted file mode 100644
index 34b4e3d46aab..000000000000
--- a/arch/arm64/crypto/crc32-ce-glue.c
+++ /dev/null
@@ -1,244 +0,0 @@
-/*
- * Accelerated CRC32(C) using arm64 NEON and Crypto Extensions instructions
- *
- * Copyright (C) 2016 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#include <linux/cpufeature.h>
-#include <linux/crc32.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/string.h>
-
-#include <crypto/internal/hash.h>
-
-#include <asm/hwcap.h>
-#include <asm/neon.h>
-#include <asm/simd.h>
-#include <asm/unaligned.h>
-
-#define PMULL_MIN_LEN		64L	/* minimum size of buffer
-					 * for crc32_pmull_le_16 */
-#define SCALE_F			16L	/* size of NEON register */
-
-asmlinkage u32 crc32_pmull_le(const u8 buf[], u64 len, u32 init_crc);
-asmlinkage u32 crc32_armv8_le(u32 init_crc, const u8 buf[], size_t len);
-
-asmlinkage u32 crc32c_pmull_le(const u8 buf[], u64 len, u32 init_crc);
-asmlinkage u32 crc32c_armv8_le(u32 init_crc, const u8 buf[], size_t len);
-
-static u32 (*fallback_crc32)(u32 init_crc, const u8 buf[], size_t len);
-static u32 (*fallback_crc32c)(u32 init_crc, const u8 buf[], size_t len);
-
-static int crc32_pmull_cra_init(struct crypto_tfm *tfm)
-{
-	u32 *key = crypto_tfm_ctx(tfm);
-
-	*key = 0;
-	return 0;
-}
-
-static int crc32c_pmull_cra_init(struct crypto_tfm *tfm)
-{
-	u32 *key = crypto_tfm_ctx(tfm);
-
-	*key = ~0;
-	return 0;
-}
-
-static int crc32_pmull_setkey(struct crypto_shash *hash, const u8 *key,
-			      unsigned int keylen)
-{
-	u32 *mctx = crypto_shash_ctx(hash);
-
-	if (keylen != sizeof(u32)) {
-		crypto_shash_set_flags(hash, CRYPTO_TFM_RES_BAD_KEY_LEN);
-		return -EINVAL;
-	}
-	*mctx = le32_to_cpup((__le32 *)key);
-	return 0;
-}
-
-static int crc32_pmull_init(struct shash_desc *desc)
-{
-	u32 *mctx = crypto_shash_ctx(desc->tfm);
-	u32 *crc = shash_desc_ctx(desc);
-
-	*crc = *mctx;
-	return 0;
-}
-
-static int crc32_update(struct shash_desc *desc, const u8 *data,
-			unsigned int length)
-{
-	u32 *crc = shash_desc_ctx(desc);
-
-	*crc = crc32_armv8_le(*crc, data, length);
-	return 0;
-}
-
-static int crc32c_update(struct shash_desc *desc, const u8 *data,
-			 unsigned int length)
-{
-	u32 *crc = shash_desc_ctx(desc);
-
-	*crc = crc32c_armv8_le(*crc, data, length);
-	return 0;
-}
-
-static int crc32_pmull_update(struct shash_desc *desc, const u8 *data,
-			 unsigned int length)
-{
-	u32 *crc = shash_desc_ctx(desc);
-	unsigned int l;
-
-	if ((u64)data % SCALE_F) {
-		l = min_t(u32, length, SCALE_F - ((u64)data % SCALE_F));
-
-		*crc = fallback_crc32(*crc, data, l);
-
-		data += l;
-		length -= l;
-	}
-
-	if (length >= PMULL_MIN_LEN && may_use_simd()) {
-		l = round_down(length, SCALE_F);
-
-		kernel_neon_begin();
-		*crc = crc32_pmull_le(data, l, *crc);
-		kernel_neon_end();
-
-		data += l;
-		length -= l;
-	}
-
-	if (length > 0)
-		*crc = fallback_crc32(*crc, data, length);
-
-	return 0;
-}
-
-static int crc32c_pmull_update(struct shash_desc *desc, const u8 *data,
-			 unsigned int length)
-{
-	u32 *crc = shash_desc_ctx(desc);
-	unsigned int l;
-
-	if ((u64)data % SCALE_F) {
-		l = min_t(u32, length, SCALE_F - ((u64)data % SCALE_F));
-
-		*crc = fallback_crc32c(*crc, data, l);
-
-		data += l;
-		length -= l;
-	}
-
-	if (length >= PMULL_MIN_LEN && may_use_simd()) {
-		l = round_down(length, SCALE_F);
-
-		kernel_neon_begin();
-		*crc = crc32c_pmull_le(data, l, *crc);
-		kernel_neon_end();
-
-		data += l;
-		length -= l;
-	}
-
-	if (length > 0) {
-		*crc = fallback_crc32c(*crc, data, length);
-	}
-
-	return 0;
-}
-
-static int crc32_pmull_final(struct shash_desc *desc, u8 *out)
-{
-	u32 *crc = shash_desc_ctx(desc);
-
-	put_unaligned_le32(*crc, out);
-	return 0;
-}
-
-static int crc32c_pmull_final(struct shash_desc *desc, u8 *out)
-{
-	u32 *crc = shash_desc_ctx(desc);
-
-	put_unaligned_le32(~*crc, out);
-	return 0;
-}
-
-static struct shash_alg crc32_pmull_algs[] = { {
-	.setkey			= crc32_pmull_setkey,
-	.init			= crc32_pmull_init,
-	.update			= crc32_update,
-	.final			= crc32_pmull_final,
-	.descsize		= sizeof(u32),
-	.digestsize		= sizeof(u32),
-
-	.base.cra_ctxsize	= sizeof(u32),
-	.base.cra_init		= crc32_pmull_cra_init,
-	.base.cra_name		= "crc32",
-	.base.cra_driver_name	= "crc32-arm64-ce",
-	.base.cra_priority	= 200,
-	.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
-	.base.cra_blocksize	= 1,
-	.base.cra_module	= THIS_MODULE,
-}, {
-	.setkey			= crc32_pmull_setkey,
-	.init			= crc32_pmull_init,
-	.update			= crc32c_update,
-	.final			= crc32c_pmull_final,
-	.descsize		= sizeof(u32),
-	.digestsize		= sizeof(u32),
-
-	.base.cra_ctxsize	= sizeof(u32),
-	.base.cra_init		= crc32c_pmull_cra_init,
-	.base.cra_name		= "crc32c",
-	.base.cra_driver_name	= "crc32c-arm64-ce",
-	.base.cra_priority	= 200,
-	.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
-	.base.cra_blocksize	= 1,
-	.base.cra_module	= THIS_MODULE,
-} };
-
-static int __init crc32_pmull_mod_init(void)
-{
-	if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && (elf_hwcap & HWCAP_PMULL)) {
-		crc32_pmull_algs[0].update = crc32_pmull_update;
-		crc32_pmull_algs[1].update = crc32c_pmull_update;
-
-		if (elf_hwcap & HWCAP_CRC32) {
-			fallback_crc32 = crc32_armv8_le;
-			fallback_crc32c = crc32c_armv8_le;
-		} else {
-			fallback_crc32 = crc32_le;
-			fallback_crc32c = __crc32c_le;
-		}
-	} else if (!(elf_hwcap & HWCAP_CRC32)) {
-		return -ENODEV;
-	}
-	return crypto_register_shashes(crc32_pmull_algs,
-				       ARRAY_SIZE(crc32_pmull_algs));
-}
-
-static void __exit crc32_pmull_mod_exit(void)
-{
-	crypto_unregister_shashes(crc32_pmull_algs,
-				  ARRAY_SIZE(crc32_pmull_algs));
-}
-
-static const struct cpu_feature crc32_cpu_feature[] = {
-	{ cpu_feature(CRC32) }, { cpu_feature(PMULL) }, { }
-};
-MODULE_DEVICE_TABLE(cpu, crc32_cpu_feature);
-
-module_init(crc32_pmull_mod_init);
-module_exit(crc32_pmull_mod_exit);
-
-MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
-MODULE_LICENSE("GPL v2");