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-rw-r--r--arch/powerpc/crypto/crct10dif-vpmsum_glue.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/arch/powerpc/crypto/crct10dif-vpmsum_glue.c b/arch/powerpc/crypto/crct10dif-vpmsum_glue.c
new file mode 100644
index 0000000000..1dc8b69151
--- /dev/null
+++ b/arch/powerpc/crypto/crct10dif-vpmsum_glue.c
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Calculate a CRC T10-DIF with vpmsum acceleration
+ *
+ * Copyright 2017, Daniel Axtens, IBM Corporation.
+ * [based on crc32c-vpmsum_glue.c]
+ */
+
+#include <linux/crc-t10dif.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 VMX_ALIGN 16
+#define VMX_ALIGN_MASK (VMX_ALIGN-1)
+
+#define VECTOR_BREAKPOINT 64
+
+u32 __crct10dif_vpmsum(u32 crc, unsigned char const *p, size_t len);
+
+static u16 crct10dif_vpmsum(u16 crci, unsigned char const *p, size_t len)
+{
+ unsigned int prealign;
+ unsigned int tail;
+ u32 crc = crci;
+
+ if (len < (VECTOR_BREAKPOINT + VMX_ALIGN) || !crypto_simd_usable())
+ return crc_t10dif_generic(crc, p, len);
+
+ if ((unsigned long)p & VMX_ALIGN_MASK) {
+ prealign = VMX_ALIGN - ((unsigned long)p & VMX_ALIGN_MASK);
+ crc = crc_t10dif_generic(crc, p, prealign);
+ len -= prealign;
+ p += prealign;
+ }
+
+ if (len & ~VMX_ALIGN_MASK) {
+ crc <<= 16;
+ preempt_disable();
+ pagefault_disable();
+ enable_kernel_altivec();
+ crc = __crct10dif_vpmsum(crc, p, len & ~VMX_ALIGN_MASK);
+ disable_kernel_altivec();
+ pagefault_enable();
+ preempt_enable();
+ crc >>= 16;
+ }
+
+ tail = len & VMX_ALIGN_MASK;
+ if (tail) {
+ p += len & ~VMX_ALIGN_MASK;
+ crc = crc_t10dif_generic(crc, p, tail);
+ }
+
+ return crc & 0xffff;
+}
+
+static int crct10dif_vpmsum_init(struct shash_desc *desc)
+{
+ u16 *crc = shash_desc_ctx(desc);
+
+ *crc = 0;
+ return 0;
+}
+
+static int crct10dif_vpmsum_update(struct shash_desc *desc, const u8 *data,
+ unsigned int length)
+{
+ u16 *crc = shash_desc_ctx(desc);
+
+ *crc = crct10dif_vpmsum(*crc, data, length);
+
+ return 0;
+}
+
+
+static int crct10dif_vpmsum_final(struct shash_desc *desc, u8 *out)
+{
+ u16 *crcp = shash_desc_ctx(desc);
+
+ *(u16 *)out = *crcp;
+ return 0;
+}
+
+static struct shash_alg alg = {
+ .init = crct10dif_vpmsum_init,
+ .update = crct10dif_vpmsum_update,
+ .final = crct10dif_vpmsum_final,
+ .descsize = CRC_T10DIF_DIGEST_SIZE,
+ .digestsize = CRC_T10DIF_DIGEST_SIZE,
+ .base = {
+ .cra_name = "crct10dif",
+ .cra_driver_name = "crct10dif-vpmsum",
+ .cra_priority = 200,
+ .cra_blocksize = CRC_T10DIF_BLOCK_SIZE,
+ .cra_module = THIS_MODULE,
+ }
+};
+
+static int __init crct10dif_vpmsum_mod_init(void)
+{
+ if (!cpu_has_feature(CPU_FTR_ARCH_207S))
+ return -ENODEV;
+
+ return crypto_register_shash(&alg);
+}
+
+static void __exit crct10dif_vpmsum_mod_fini(void)
+{
+ crypto_unregister_shash(&alg);
+}
+
+module_cpu_feature_match(PPC_MODULE_FEATURE_VEC_CRYPTO, crct10dif_vpmsum_mod_init);
+module_exit(crct10dif_vpmsum_mod_fini);
+
+MODULE_AUTHOR("Daniel Axtens <dja@axtens.net>");
+MODULE_DESCRIPTION("CRCT10DIF using vector polynomial multiply-sum instructions");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_CRYPTO("crct10dif");
+MODULE_ALIAS_CRYPTO("crct10dif-vpmsum");