summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/crypto/crc32c-vpmsum_glue.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/crypto/crc32c-vpmsum_glue.c')
-rw-r--r--arch/powerpc/crypto/crc32c-vpmsum_glue.c173
1 files changed, 173 insertions, 0 deletions
diff --git a/arch/powerpc/crypto/crc32c-vpmsum_glue.c b/arch/powerpc/crypto/crc32c-vpmsum_glue.c
new file mode 100644
index 000000000..63760b7db
--- /dev/null
+++ b/arch/powerpc/crypto/crc32c-vpmsum_glue.c
@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/crc32.h>
+#include <crypto/internal/hash.h>
+#include <crypto/internal/simd.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/cpufeature.h>
+#include <asm/simd.h>
+#include <asm/switch_to.h>
+
+#define CHKSUM_BLOCK_SIZE 1
+#define CHKSUM_DIGEST_SIZE 4
+
+#define VMX_ALIGN 16
+#define VMX_ALIGN_MASK (VMX_ALIGN-1)
+
+#define VECTOR_BREAKPOINT 512
+
+u32 __crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len);
+
+static u32 crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len)
+{
+ unsigned int prealign;
+ unsigned int tail;
+
+ if (len < (VECTOR_BREAKPOINT + VMX_ALIGN) || !crypto_simd_usable())
+ return __crc32c_le(crc, p, len);
+
+ if ((unsigned long)p & VMX_ALIGN_MASK) {
+ prealign = VMX_ALIGN - ((unsigned long)p & VMX_ALIGN_MASK);
+ crc = __crc32c_le(crc, p, prealign);
+ len -= prealign;
+ p += prealign;
+ }
+
+ if (len & ~VMX_ALIGN_MASK) {
+ preempt_disable();
+ pagefault_disable();
+ enable_kernel_altivec();
+ crc = __crc32c_vpmsum(crc, p, len & ~VMX_ALIGN_MASK);
+ disable_kernel_altivec();
+ pagefault_enable();
+ preempt_enable();
+ }
+
+ tail = len & VMX_ALIGN_MASK;
+ if (tail) {
+ p += len & ~VMX_ALIGN_MASK;
+ crc = __crc32c_le(crc, p, tail);
+ }
+
+ return crc;
+}
+
+static int crc32c_vpmsum_cra_init(struct crypto_tfm *tfm)
+{
+ u32 *key = crypto_tfm_ctx(tfm);
+
+ *key = ~0;
+
+ 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 crc32c_vpmsum_setkey(struct crypto_shash *hash, const u8 *key,
+ unsigned int keylen)
+{
+ u32 *mctx = crypto_shash_ctx(hash);
+
+ if (keylen != sizeof(u32))
+ return -EINVAL;
+ *mctx = le32_to_cpup((__le32 *)key);
+ return 0;
+}
+
+static int crc32c_vpmsum_init(struct shash_desc *desc)
+{
+ u32 *mctx = crypto_shash_ctx(desc->tfm);
+ u32 *crcp = shash_desc_ctx(desc);
+
+ *crcp = *mctx;
+
+ return 0;
+}
+
+static int crc32c_vpmsum_update(struct shash_desc *desc, const u8 *data,
+ unsigned int len)
+{
+ u32 *crcp = shash_desc_ctx(desc);
+
+ *crcp = crc32c_vpmsum(*crcp, data, len);
+
+ return 0;
+}
+
+static int __crc32c_vpmsum_finup(u32 *crcp, const u8 *data, unsigned int len,
+ u8 *out)
+{
+ *(__le32 *)out = ~cpu_to_le32(crc32c_vpmsum(*crcp, data, len));
+
+ return 0;
+}
+
+static int crc32c_vpmsum_finup(struct shash_desc *desc, const u8 *data,
+ unsigned int len, u8 *out)
+{
+ return __crc32c_vpmsum_finup(shash_desc_ctx(desc), data, len, out);
+}
+
+static int crc32c_vpmsum_final(struct shash_desc *desc, u8 *out)
+{
+ u32 *crcp = shash_desc_ctx(desc);
+
+ *(__le32 *)out = ~cpu_to_le32p(crcp);
+
+ return 0;
+}
+
+static int crc32c_vpmsum_digest(struct shash_desc *desc, const u8 *data,
+ unsigned int len, u8 *out)
+{
+ return __crc32c_vpmsum_finup(crypto_shash_ctx(desc->tfm), data, len,
+ out);
+}
+
+static struct shash_alg alg = {
+ .setkey = crc32c_vpmsum_setkey,
+ .init = crc32c_vpmsum_init,
+ .update = crc32c_vpmsum_update,
+ .final = crc32c_vpmsum_final,
+ .finup = crc32c_vpmsum_finup,
+ .digest = crc32c_vpmsum_digest,
+ .descsize = sizeof(u32),
+ .digestsize = CHKSUM_DIGEST_SIZE,
+ .base = {
+ .cra_name = "crc32c",
+ .cra_driver_name = "crc32c-vpmsum",
+ .cra_priority = 200,
+ .cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
+ .cra_blocksize = CHKSUM_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(u32),
+ .cra_module = THIS_MODULE,
+ .cra_init = crc32c_vpmsum_cra_init,
+ }
+};
+
+static int __init crc32c_vpmsum_mod_init(void)
+{
+ if (!cpu_has_feature(CPU_FTR_ARCH_207S))
+ return -ENODEV;
+
+ return crypto_register_shash(&alg);
+}
+
+static void __exit crc32c_vpmsum_mod_fini(void)
+{
+ crypto_unregister_shash(&alg);
+}
+
+module_cpu_feature_match(PPC_MODULE_FEATURE_VEC_CRYPTO, crc32c_vpmsum_mod_init);
+module_exit(crc32c_vpmsum_mod_fini);
+
+MODULE_AUTHOR("Anton Blanchard <anton@samba.org>");
+MODULE_DESCRIPTION("CRC32C using vector polynomial multiply-sum instructions");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_CRYPTO("crc32c");
+MODULE_ALIAS_CRYPTO("crc32c-vpmsum");