crypto: x86/aesni - Refactor the common address alignment code

The address alignment code has been duplicated for each mode. Instead
of duplicating the same code, refactor the alignment code and simplify
the alignment helpers.
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Link: https://lore.kernel.org/all/20230526065414.GB875@sol.localdomain/Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Cc: linux-crypto@vger.kernel.org
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

arch/x86/crypto/aesni-intel_glue.c

@@ -80,6 +80,13 @@ struct gcm_context_data {
 	u8 hash_keys[GCM_BLOCK_LEN * 16];
 };
 
+static inline void *aes_align_addr(void *addr)
+{
+	if (crypto_tfm_ctx_alignment() >= AESNI_ALIGN)
+		return addr;
+	return PTR_ALIGN(addr, AESNI_ALIGN);
+}
+
 asmlinkage int aesni_set_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
 			     unsigned int key_len);
 asmlinkage void aesni_enc(const void *ctx, u8 *out, const u8 *in);
@@ -201,32 +208,19 @@ static __ro_after_init DEFINE_STATIC_KEY_FALSE(gcm_use_avx2);
 static inline struct
 aesni_rfc4106_gcm_ctx *aesni_rfc4106_gcm_ctx_get(struct crypto_aead *tfm)
 {
-	unsigned long align = AESNI_ALIGN;
-
-	if (align <= crypto_tfm_ctx_alignment())
-		align = 1;
-	return PTR_ALIGN(crypto_aead_ctx(tfm), align);
+	return aes_align_addr(crypto_aead_ctx(tfm));
 }
 
 static inline struct
 generic_gcmaes_ctx *generic_gcmaes_ctx_get(struct crypto_aead *tfm)
 {
-	unsigned long align = AESNI_ALIGN;
-
-	if (align <= crypto_tfm_ctx_alignment())
-		align = 1;
-	return PTR_ALIGN(crypto_aead_ctx(tfm), align);
+	return aes_align_addr(crypto_aead_ctx(tfm));
 }
 #endif
 
 static inline struct crypto_aes_ctx *aes_ctx(void *raw_ctx)
 {
-	unsigned long addr = (unsigned long)raw_ctx;
-	unsigned long align = AESNI_ALIGN;
-
-	if (align <= crypto_tfm_ctx_alignment())
-		align = 1;
-	return (struct crypto_aes_ctx *)ALIGN(addr, align);
+	return aes_align_addr(raw_ctx);
 }
 
 static int aes_set_key_common(struct crypto_aes_ctx *ctx,