crypto: serpent-sse2 - split generic glue code to new helper module

Now that serpent-sse2 glue code has been made generic, it can be split to
separate module.

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 115 insertions, 0 deletions

diff --git a/arch/x86/include/asm/crypto/glue_helper.h b/arch/x86/include/asm/crypto/glue_helper.h
new file mode 100644
index 000000000000..3e408bddc96f
--- /dev/null
+++ b/arch/x86/include/asm/crypto/glue_helper.h
@@ -0,0 +1,115 @@
+/*
+ * Shared glue code for 128bit block ciphers
+ */
+
+#ifndef _CRYPTO_GLUE_HELPER_H
+#define _CRYPTO_GLUE_HELPER_H
+
+#include <linux/kernel.h>
+#include <linux/crypto.h>
+#include <asm/i387.h>
+#include <crypto/b128ops.h>
+
+typedef void (*common_glue_func_t)(void *ctx, u8 *dst, const u8 *src);
+typedef void (*common_glue_cbc_func_t)(void *ctx, u128 *dst, const u128 *src);
+typedef void (*common_glue_ctr_func_t)(void *ctx, u128 *dst, const u128 *src,
+                                       u128 *iv);
+
+#define GLUE_FUNC_CAST(fn) ((common_glue_func_t)(fn))
+#define GLUE_CBC_FUNC_CAST(fn) ((common_glue_cbc_func_t)(fn))
+#define GLUE_CTR_FUNC_CAST(fn) ((common_glue_ctr_func_t)(fn))
+
+struct common_glue_func_entry {
+        unsigned int num_blocks; /* number of blocks that @fn will process */
+        union {
+                common_glue_func_t ecb;
+                common_glue_cbc_func_t cbc;
+                common_glue_ctr_func_t ctr;
+        } fn_u;
+};
+
+struct common_glue_ctx {
+        unsigned int num_funcs;
+        int fpu_blocks_limit; /* -1 means fpu not needed at all */
+
+        /*
+         * First funcs entry must have largest num_blocks and last funcs entry
+         * must have num_blocks == 1!
+         */
+        struct common_glue_func_entry funcs[];
+};
+
+static inline bool glue_fpu_begin(unsigned int bsize, int fpu_blocks_limit,
+                                  struct blkcipher_desc *desc,
+                                  bool fpu_enabled, unsigned int nbytes)
+{
+        if (likely(fpu_blocks_limit < 0))
+                return false;
+
+        if (fpu_enabled)
+                return true;
+
+        /*
+         * Vector-registers are only used when chunk to be processed is large
+         * enough, so do not enable FPU until it is necessary.
+         */
+        if (nbytes < bsize * (unsigned int)fpu_blocks_limit)
+                return false;
+
+        if (desc) {
+                /* prevent sleeping if FPU is in use */
+                desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
+        }
+
+        kernel_fpu_begin();
+        return true;
+}
+
+static inline void glue_fpu_end(bool fpu_enabled)
+{
+        if (fpu_enabled)
+                kernel_fpu_end();
+}
+
+static inline void u128_to_be128(be128 *dst, const u128 *src)
+{
+        dst->a = cpu_to_be64(src->a);
+        dst->b = cpu_to_be64(src->b);
+}
+
+static inline void be128_to_u128(u128 *dst, const be128 *src)
+{
+        dst->a = be64_to_cpu(src->a);
+        dst->b = be64_to_cpu(src->b);
+}
+
+static inline void u128_inc(u128 *i)
+{
+        i->b++;
+        if (!i->b)
+                i->a++;
+}
+
+extern int glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx,
+                                 struct blkcipher_desc *desc,
+                                 struct scatterlist *dst,
+                                 struct scatterlist *src, unsigned int nbytes);
+
+extern int glue_cbc_encrypt_128bit(const common_glue_func_t fn,
+                                   struct blkcipher_desc *desc,
+                                   struct scatterlist *dst,
+                                   struct scatterlist *src,
+                                   unsigned int nbytes);
+
+extern int glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx,
+                                   struct blkcipher_desc *desc,
+                                   struct scatterlist *dst,
+                                   struct scatterlist *src,
+                                   unsigned int nbytes);
+
+extern int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
+                                 struct blkcipher_desc *desc,
+                                 struct scatterlist *dst,
+                                 struct scatterlist *src, unsigned int nbytes);
+
+#endif /* _CRYPTO_GLUE_HELPER_H */