--- /dev/null
+/*
+ * crc32-arm64.c - CRC32 and CRC32C using optional ARMv8 instructions
+ *
+ * Module based on crypto/crc32c_generic.c
+ *
+ * CRC32 loop taken from Ed Nevill's Hadoop CRC patch
+ * http://mail-archives.apache.org/mod_mbox/hadoop-common-dev/201406.mbox/%3C1403687030.3355.19.camel%40localhost.localdomain%3E
+ *
+ * Using inline assembly instead of intrinsics in order to be backwards
+ * compatible with older compilers.
+ *
+ * Copyright (C) 2014 Linaro Ltd <yazen.ghannam@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/unaligned/access_ok.h>
+#include <linux/cpufeature.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/string.h>
+
+#include <crypto/internal/hash.h>
+
+MODULE_AUTHOR("Yazen Ghannam <yazen.ghannam@linaro.org>");
+MODULE_DESCRIPTION("CRC32 and CRC32C using optional ARMv8 instructions");
+MODULE_LICENSE("GPL v2");
+
+#define CRC32X(crc, value) __asm__("crc32x %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value))
+#define CRC32W(crc, value) __asm__("crc32w %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
+#define CRC32H(crc, value) __asm__("crc32h %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
+#define CRC32B(crc, value) __asm__("crc32b %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
+#define CRC32CX(crc, value) __asm__("crc32cx %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value))
+#define CRC32CW(crc, value) __asm__("crc32cw %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
+#define CRC32CH(crc, value) __asm__("crc32ch %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
+#define CRC32CB(crc, value) __asm__("crc32cb %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
+
+static u32 crc32_arm64_le_hw(u32 crc, const u8 *p, unsigned int len)
+{
+ s64 length = len;
+
+ while ((length -= sizeof(u64)) >= 0) {
+ CRC32X(crc, get_unaligned_le64(p));
+ p += sizeof(u64);
+ }
+
+ /* The following is more efficient than the straight loop */
+ if (length & sizeof(u32)) {
+ CRC32W(crc, get_unaligned_le32(p));
+ p += sizeof(u32);
+ }
+ if (length & sizeof(u16)) {
+ CRC32H(crc, get_unaligned_le16(p));
+ p += sizeof(u16);
+ }
+ if (length & sizeof(u8))
+ CRC32B(crc, *p);
+
+ return crc;
+}
+
+static u32 crc32c_arm64_le_hw(u32 crc, const u8 *p, unsigned int len)
+{
+ s64 length = len;
+
+ while ((length -= sizeof(u64)) >= 0) {
+ CRC32CX(crc, get_unaligned_le64(p));
+ p += sizeof(u64);
+ }
+
+ /* The following is more efficient than the straight loop */
+ if (length & sizeof(u32)) {
+ CRC32CW(crc, get_unaligned_le32(p));
+ p += sizeof(u32);
+ }
+ if (length & sizeof(u16)) {
+ CRC32CH(crc, get_unaligned_le16(p));
+ p += sizeof(u16);
+ }
+ if (length & sizeof(u8))
+ CRC32CB(crc, *p);
+
+ return crc;
+}
+
+#define CHKSUM_BLOCK_SIZE 1
+#define CHKSUM_DIGEST_SIZE 4
+
+struct chksum_ctx {
+ u32 key;
+};
+
+struct chksum_desc_ctx {
+ u32 crc;
+};
+
+static int chksum_init(struct shash_desc *desc)
+{
+ struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
+ struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
+
+ ctx->crc = mctx->key;
+
+ return 0;
+}
+
+/*
+ * Setting the seed allows arbitrary accumulators and flexible XOR policy
+ * If your algorithm starts with ~0, then XOR with ~0 before you set
+ * the seed.
+ */
+static int chksum_setkey(struct crypto_shash *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct chksum_ctx *mctx = crypto_shash_ctx(tfm);
+
+ if (keylen != sizeof(mctx->key)) {
+ crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+ return -EINVAL;
+ }
+ mctx->key = get_unaligned_le32(key);
+ return 0;
+}
+
+static int chksum_update(struct shash_desc *desc, const u8 *data,
+ unsigned int length)
+{
+ struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
+
+ ctx->crc = crc32_arm64_le_hw(ctx->crc, data, length);
+ return 0;
+}
+
+static int chksumc_update(struct shash_desc *desc, const u8 *data,
+ unsigned int length)
+{
+ struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
+
+ ctx->crc = crc32c_arm64_le_hw(ctx->crc, data, length);
+ return 0;
+}
+
+static int chksum_final(struct shash_desc *desc, u8 *out)
+{
+ struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
+
+ put_unaligned_le32(ctx->crc, out);
+ return 0;
+}
+
+static int chksumc_final(struct shash_desc *desc, u8 *out)
+{
+ struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
+
+ put_unaligned_le32(~ctx->crc, out);
+ return 0;
+}
+
+static int __chksum_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)
+{
+ put_unaligned_le32(crc32_arm64_le_hw(crc, data, len), out);
+ return 0;
+}
+
+static int __chksumc_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)
+{
+ put_unaligned_le32(~crc32c_arm64_le_hw(crc, data, len), out);
+ return 0;
+}
+
+static int chksum_finup(struct shash_desc *desc, const u8 *data,
+ unsigned int len, u8 *out)
+{
+ struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
+
+ return __chksum_finup(ctx->crc, data, len, out);
+}
+
+static int chksumc_finup(struct shash_desc *desc, const u8 *data,
+ unsigned int len, u8 *out)
+{
+ struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
+
+ return __chksumc_finup(ctx->crc, data, len, out);
+}
+
+static int chksum_digest(struct shash_desc *desc, const u8 *data,
+ unsigned int length, u8 *out)
+{
+ struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
+
+ return __chksum_finup(mctx->key, data, length, out);
+}
+
+static int chksumc_digest(struct shash_desc *desc, const u8 *data,
+ unsigned int length, u8 *out)
+{
+ struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
+
+ return __chksumc_finup(mctx->key, data, length, out);
+}
+
+static int crc32_cra_init(struct crypto_tfm *tfm)
+{
+ struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
+
+ mctx->key = 0;
+ return 0;
+}
+
+static int crc32c_cra_init(struct crypto_tfm *tfm)
+{
+ struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
+
+ mctx->key = ~0;
+ return 0;
+}
+
+static struct shash_alg crc32_alg = {
+ .digestsize = CHKSUM_DIGEST_SIZE,
+ .setkey = chksum_setkey,
+ .init = chksum_init,
+ .update = chksum_update,
+ .final = chksum_final,
+ .finup = chksum_finup,
+ .digest = chksum_digest,
+ .descsize = sizeof(struct chksum_desc_ctx),
+ .base = {
+ .cra_name = "crc32",
+ .cra_driver_name = "crc32-arm64-hw",
+ .cra_priority = 300,
+ .cra_blocksize = CHKSUM_BLOCK_SIZE,
+ .cra_alignmask = 0,
+ .cra_ctxsize = sizeof(struct chksum_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_init = crc32_cra_init,
+ }
+};
+
+static struct shash_alg crc32c_alg = {
+ .digestsize = CHKSUM_DIGEST_SIZE,
+ .setkey = chksum_setkey,
+ .init = chksum_init,
+ .update = chksumc_update,
+ .final = chksumc_final,
+ .finup = chksumc_finup,
+ .digest = chksumc_digest,
+ .descsize = sizeof(struct chksum_desc_ctx),
+ .base = {
+ .cra_name = "crc32c",
+ .cra_driver_name = "crc32c-arm64-hw",
+ .cra_priority = 300,
+ .cra_blocksize = CHKSUM_BLOCK_SIZE,
+ .cra_alignmask = 0,
+ .cra_ctxsize = sizeof(struct chksum_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_init = crc32c_cra_init,
+ }
+};
+
+static int __init crc32_mod_init(void)
+{
+ int err;
+
+ err = crypto_register_shash(&crc32_alg);
+
+ if (err)
+ return err;
+
+ err = crypto_register_shash(&crc32c_alg);
+
+ if (err) {
+ crypto_unregister_shash(&crc32_alg);
+ return err;
+ }
+
+ return 0;
+}
+
+static void __exit crc32_mod_exit(void)
+{
+ crypto_unregister_shash(&crc32_alg);
+ crypto_unregister_shash(&crc32c_alg);
+}
+
+module_cpu_feature_match(CRC32, crc32_mod_init);
+module_exit(crc32_mod_exit);
Code Review / kvmfornfv.git / blobdiff