s390/crc32-vx: add crypto API module for optimized CRC-32 algorithms
[cascardo/linux.git] / arch / s390 / crypto / crc32-vx.c
diff --git a/arch/s390/crypto/crc32-vx.c b/arch/s390/crypto/crc32-vx.c
new file mode 100644 (file)
index 0000000..577ae1d
--- /dev/null
@@ -0,0 +1,310 @@
+/*
+ * Crypto-API module for CRC-32 algorithms implemented with the
+ * z/Architecture Vector Extension Facility.
+ *
+ * Copyright IBM Corp. 2015
+ * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
+ */
+#define KMSG_COMPONENT "crc32-vx"
+#define pr_fmt(fmt)    KMSG_COMPONENT ": " fmt
+
+#include <linux/module.h>
+#include <linux/cpufeature.h>
+#include <linux/crc32.h>
+#include <crypto/internal/hash.h>
+#include <asm/fpu/api.h>
+
+
+#define CRC32_BLOCK_SIZE       1
+#define CRC32_DIGEST_SIZE      4
+
+#define VX_MIN_LEN             64
+#define VX_ALIGNMENT           16L
+#define VX_ALIGN_MASK          (VX_ALIGNMENT - 1)
+
+struct crc_ctx {
+       u32 key;
+};
+
+struct crc_desc_ctx {
+       u32 crc;
+};
+
+/* Prototypes for functions in assembly files */
+u32 crc32_le_vgfm_16(u32 crc, unsigned char const *buf, size_t size);
+u32 crc32_be_vgfm_16(u32 crc, unsigned char const *buf, size_t size);
+u32 crc32c_le_vgfm_16(u32 crc, unsigned char const *buf, size_t size);
+
+/*
+ * DEFINE_CRC32_VX() - Define a CRC-32 function using the vector extension
+ *
+ * Creates a function to perform a particular CRC-32 computation. Depending
+ * on the message buffer, the hardware-accelerated or software implementation
+ * is used.   Note that the message buffer is aligned to improve fetch
+ * operations of VECTOR LOAD MULTIPLE instructions.
+ *
+ */
+#define DEFINE_CRC32_VX(___fname, ___crc32_vx, ___crc32_sw)                \
+       static u32 __pure ___fname(u32 crc,                                 \
+                               unsigned char const *data, size_t datalen)  \
+       {                                                                   \
+               struct kernel_fpu vxstate;                                  \
+               unsigned long prealign, aligned, remaining;                 \
+                                                                           \
+               if ((unsigned long)data & VX_ALIGN_MASK) {                  \
+                       prealign = VX_ALIGNMENT -                           \
+                                 ((unsigned long)data & VX_ALIGN_MASK);    \
+                       datalen -= prealign;                                \
+                       crc = ___crc32_sw(crc, data, prealign);             \
+                       data = (void *)((unsigned long)data + prealign);    \
+               }                                                           \
+                                                                           \
+               if (datalen < VX_MIN_LEN)                                   \
+                       return ___crc32_sw(crc, data, datalen);             \
+                                                                           \
+               aligned = datalen & ~VX_ALIGN_MASK;                         \
+               remaining = datalen & VX_ALIGN_MASK;                        \
+                                                                           \
+               kernel_fpu_begin(&vxstate, KERNEL_VXR_LOW);                 \
+               crc = ___crc32_vx(crc, data, aligned);                      \
+               kernel_fpu_end(&vxstate);                                   \
+                                                                           \
+               if (remaining)                                              \
+                       crc = ___crc32_sw(crc, data + aligned, remaining);  \
+                                                                           \
+               return crc;                                                 \
+       }
+
+DEFINE_CRC32_VX(crc32_le_vx, crc32_le_vgfm_16, crc32_le)
+DEFINE_CRC32_VX(crc32_be_vx, crc32_be_vgfm_16, crc32_be)
+DEFINE_CRC32_VX(crc32c_le_vx, crc32c_le_vgfm_16, __crc32c_le)
+
+
+static int crc32_vx_cra_init_zero(struct crypto_tfm *tfm)
+{
+       struct crc_ctx *mctx = crypto_tfm_ctx(tfm);
+
+       mctx->key = 0;
+       return 0;
+}
+
+static int crc32_vx_cra_init_invert(struct crypto_tfm *tfm)
+{
+       struct crc_ctx *mctx = crypto_tfm_ctx(tfm);
+
+       mctx->key = ~0;
+       return 0;
+}
+
+static int crc32_vx_init(struct shash_desc *desc)
+{
+       struct crc_ctx *mctx = crypto_shash_ctx(desc->tfm);
+       struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
+
+       ctx->crc = mctx->key;
+       return 0;
+}
+
+static int crc32_vx_setkey(struct crypto_shash *tfm, const u8 *newkey,
+                          unsigned int newkeylen)
+{
+       struct crc_ctx *mctx = crypto_shash_ctx(tfm);
+
+       if (newkeylen != sizeof(mctx->key)) {
+               crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+               return -EINVAL;
+       }
+       mctx->key = le32_to_cpu(*(__le32 *)newkey);
+       return 0;
+}
+
+static int crc32be_vx_setkey(struct crypto_shash *tfm, const u8 *newkey,
+                            unsigned int newkeylen)
+{
+       struct crc_ctx *mctx = crypto_shash_ctx(tfm);
+
+       if (newkeylen != sizeof(mctx->key)) {
+               crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+               return -EINVAL;
+       }
+       mctx->key = be32_to_cpu(*(__be32 *)newkey);
+       return 0;
+}
+
+static int crc32le_vx_final(struct shash_desc *desc, u8 *out)
+{
+       struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
+
+       *(__le32 *)out = cpu_to_le32p(&ctx->crc);
+       return 0;
+}
+
+static int crc32be_vx_final(struct shash_desc *desc, u8 *out)
+{
+       struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
+
+       *(__be32 *)out = cpu_to_be32p(&ctx->crc);
+       return 0;
+}
+
+static int crc32c_vx_final(struct shash_desc *desc, u8 *out)
+{
+       struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
+
+       /*
+        * Perform a final XOR with 0xFFFFFFFF to be in sync
+        * with the generic crc32c shash implementation.
+        */
+       *(__le32 *)out = ~cpu_to_le32p(&ctx->crc);
+       return 0;
+}
+
+static int __crc32le_vx_finup(u32 *crc, const u8 *data, unsigned int len,
+                             u8 *out)
+{
+       *(__le32 *)out = cpu_to_le32(crc32_le_vx(*crc, data, len));
+       return 0;
+}
+
+static int __crc32be_vx_finup(u32 *crc, const u8 *data, unsigned int len,
+                             u8 *out)
+{
+       *(__be32 *)out = cpu_to_be32(crc32_be_vx(*crc, data, len));
+       return 0;
+}
+
+static int __crc32c_vx_finup(u32 *crc, const u8 *data, unsigned int len,
+                            u8 *out)
+{
+       /*
+        * Perform a final XOR with 0xFFFFFFFF to be in sync
+        * with the generic crc32c shash implementation.
+        */
+       *(__le32 *)out = ~cpu_to_le32(crc32c_le_vx(*crc, data, len));
+       return 0;
+}
+
+
+#define CRC32_VX_FINUP(alg, func)                                            \
+       static int alg ## _vx_finup(struct shash_desc *desc, const u8 *data,  \
+                                  unsigned int datalen, u8 *out)             \
+       {                                                                     \
+               return __ ## alg ## _vx_finup(shash_desc_ctx(desc),           \
+                                             data, datalen, out);            \
+       }
+
+CRC32_VX_FINUP(crc32le, crc32_le_vx)
+CRC32_VX_FINUP(crc32be, crc32_be_vx)
+CRC32_VX_FINUP(crc32c, crc32c_le_vx)
+
+#define CRC32_VX_DIGEST(alg, func)                                           \
+       static int alg ## _vx_digest(struct shash_desc *desc, const u8 *data, \
+                                    unsigned int len, u8 *out)               \
+       {                                                                     \
+               return __ ## alg ## _vx_finup(crypto_shash_ctx(desc->tfm),    \
+                                             data, len, out);                \
+       }
+
+CRC32_VX_DIGEST(crc32le, crc32_le_vx)
+CRC32_VX_DIGEST(crc32be, crc32_be_vx)
+CRC32_VX_DIGEST(crc32c, crc32c_le_vx)
+
+#define CRC32_VX_UPDATE(alg, func)                                           \
+       static int alg ## _vx_update(struct shash_desc *desc, const u8 *data, \
+                                    unsigned int datalen)                    \
+       {                                                                     \
+               struct crc_desc_ctx *ctx = shash_desc_ctx(desc);              \
+               ctx->crc = func(ctx->crc, data, datalen);                     \
+               return 0;                                                     \
+       }
+
+CRC32_VX_UPDATE(crc32le, crc32_le_vx)
+CRC32_VX_UPDATE(crc32be, crc32_be_vx)
+CRC32_VX_UPDATE(crc32c, crc32c_le_vx)
+
+
+static struct shash_alg crc32_vx_algs[] = {
+       /* CRC-32 LE */
+       {
+               .init           =       crc32_vx_init,
+               .setkey         =       crc32_vx_setkey,
+               .update         =       crc32le_vx_update,
+               .final          =       crc32le_vx_final,
+               .finup          =       crc32le_vx_finup,
+               .digest         =       crc32le_vx_digest,
+               .descsize       =       sizeof(struct crc_desc_ctx),
+               .digestsize     =       CRC32_DIGEST_SIZE,
+               .base           =       {
+                       .cra_name        = "crc32",
+                       .cra_driver_name = "crc32-vx",
+                       .cra_priority    = 200,
+                       .cra_blocksize   = CRC32_BLOCK_SIZE,
+                       .cra_ctxsize     = sizeof(struct crc_ctx),
+                       .cra_module      = THIS_MODULE,
+                       .cra_init        = crc32_vx_cra_init_zero,
+               },
+       },
+       /* CRC-32 BE */
+       {
+               .init           =       crc32_vx_init,
+               .setkey         =       crc32be_vx_setkey,
+               .update         =       crc32be_vx_update,
+               .final          =       crc32be_vx_final,
+               .finup          =       crc32be_vx_finup,
+               .digest         =       crc32be_vx_digest,
+               .descsize       =       sizeof(struct crc_desc_ctx),
+               .digestsize     =       CRC32_DIGEST_SIZE,
+               .base           =       {
+                       .cra_name        = "crc32be",
+                       .cra_driver_name = "crc32be-vx",
+                       .cra_priority    = 200,
+                       .cra_blocksize   = CRC32_BLOCK_SIZE,
+                       .cra_ctxsize     = sizeof(struct crc_ctx),
+                       .cra_module      = THIS_MODULE,
+                       .cra_init        = crc32_vx_cra_init_zero,
+               },
+       },
+       /* CRC-32C LE */
+       {
+               .init           =       crc32_vx_init,
+               .setkey         =       crc32_vx_setkey,
+               .update         =       crc32c_vx_update,
+               .final          =       crc32c_vx_final,
+               .finup          =       crc32c_vx_finup,
+               .digest         =       crc32c_vx_digest,
+               .descsize       =       sizeof(struct crc_desc_ctx),
+               .digestsize     =       CRC32_DIGEST_SIZE,
+               .base           =       {
+                       .cra_name        = "crc32c",
+                       .cra_driver_name = "crc32c-vx",
+                       .cra_priority    = 200,
+                       .cra_blocksize   = CRC32_BLOCK_SIZE,
+                       .cra_ctxsize     = sizeof(struct crc_ctx),
+                       .cra_module      = THIS_MODULE,
+                       .cra_init        = crc32_vx_cra_init_invert,
+               },
+       },
+};
+
+
+static int __init crc_vx_mod_init(void)
+{
+       return crypto_register_shashes(crc32_vx_algs,
+                                      ARRAY_SIZE(crc32_vx_algs));
+}
+
+static void __exit crc_vx_mod_exit(void)
+{
+       crypto_unregister_shashes(crc32_vx_algs, ARRAY_SIZE(crc32_vx_algs));
+}
+
+module_cpu_feature_match(VXRS, crc_vx_mod_init);
+module_exit(crc_vx_mod_exit);
+
+MODULE_AUTHOR("Hendrik Brueckner <brueckner@linux.vnet.ibm.com>");
+MODULE_LICENSE("GPL");
+
+MODULE_ALIAS_CRYPTO("crc32");
+MODULE_ALIAS_CRYPTO("crc32-vx");
+MODULE_ALIAS_CRYPTO("crc32c");
+MODULE_ALIAS_CRYPTO("crc32c-vx");