lib/crc32: remove unused combination support

index 8c1883b81b420..36bbc0405aa04 100644
@@ -46,35 +46,10 @@ static inline u32 crc32c(u32 crc, const void *p, size_t len)
 u32 crc32_optimizations(void);
 #else
 static inline u32 crc32_optimizations(void) { return 0; }
 #endif
 
-/**
- * crc32_le_combine - Combine two crc32 check values into one. For two
- * 		      sequences of bytes, seq1 and seq2 with lengths len1
- * 		      and len2, crc32_le() check values were calculated
- * 		      for each, crc1 and crc2.
- *
- * @crc1: crc32 of the first block
- * @crc2: crc32 of the second block
- * @len2: length of the second block
- *
- * Return: The crc32_le() check value of seq1 and seq2 concatenated,
- * 	   requiring only crc1, crc2, and len2. Note: If seq_full denotes
- * 	   the concatenated memory area of seq1 with seq2, and crc_full
- * 	   the crc32_le() value of seq_full, then crc_full ==
- * 	   crc32_le_combine(crc1, crc2, len2) when crc_full was seeded
- * 	   with the same initializer as crc1, and crc2 seed was 0. See
- * 	   also crc32_combine_test().
- */
-u32 crc32_le_shift(u32 crc, size_t len);
-
-static inline u32 crc32_le_combine(u32 crc1, u32 crc2, size_t len2)
-{
-	return crc32_le_shift(crc1, len2) ^ crc2;
-}
-
 #define crc32(seed, data, length)  crc32_le(seed, (unsigned char const *)(data), length)
 
 /*
  * Helpers for hash table generation of ethernet nics:
  *

87 lines not on this page · raw message

index 064c2d5815579..f08d985d8860e 100644
@@ -34,18 +34,16 @@ static size_t test_buflen;
  *	  Bit-reversed if @le is true.
  * @func: The function to compute a CRC.  The type signature uses u64 so that it
  *	  can fit any CRC up to CRC-64.  The CRC is passed in, and is expected
  *	  to be returned in, the least significant bits of the u64.  The
  *	  function is expected to *not* invert the CRC at the beginning and end.
- * @combine_func: Optional function to combine two CRCs.
  */
 struct crc_variant {
 	int bits;
 	bool le;
 	u64 poly;
 	u64 (*func)(u64 crc, const u8 *p, size_t len);
-	u64 (*combine_func)(u64 crc1, u64 crc2, size_t len2);
 };
 
 static u32 rand32(void)
 {
 	return prandom_u32_state(&rng);

@@ -142,11 +140,11 @@ static size_t generate_random_length(size_t max_length)
 	}
 	return len % (max_length + 1);
 }
 
 /* Test that v->func gives the same CRCs as a reference implementation. */
-static void crc_main_test(struct kunit *test, const struct crc_variant *v)
+static void crc_test(struct kunit *test, const struct crc_variant *v)
 {
 	size_t i;
 
 	for (i = 0; i < CRC_KUNIT_NUM_TEST_ITERS; i++) {
 		u64 init_crc, expected_crc, actual_crc;

@@ -186,39 +184,10 @@ static void crc_main_test(struct kunit *test, const struct crc_variant *v)
 				    "Wrong result with len=%zu offset=%zu nosimd=%d",
 				    len, offset, nosimd);
 	}
 }
 
-/* Test that CRC(concat(A, B)) == combine_CRCs(CRC(A), CRC(B), len(B)). */
-static void crc_combine_test(struct kunit *test, const struct crc_variant *v)
-{
-	int i;
-
-	for (i = 0; i < 100; i++) {
-		u64 init_crc = generate_random_initial_crc(v);
-		size_t len1 = generate_random_length(CRC_KUNIT_MAX_LEN);
-		size_t len2 = generate_random_length(CRC_KUNIT_MAX_LEN - len1);
-		u64 crc1, crc2, expected_crc, actual_crc;
-
-		prandom_bytes_state(&rng, test_buffer, len1 + len2);
-		crc1 = v->func(init_crc, test_buffer, len1);
-		crc2 = v->func(0, &test_buffer[len1], len2);
-		expected_crc = v->func(init_crc, test_buffer, len1 + len2);
-		actual_crc = v->combine_func(crc1, crc2, len2);
-		KUNIT_EXPECT_EQ_MSG(test, expected_crc, actual_crc,
-				    "CRC combination gave wrong result with len1=%zu len2=%zu\n",
-				    len1, len2);
-	}
-}
-
-static void crc_test(struct kunit *test, const struct crc_variant *v)
-{
-	crc_main_test(test, v);
-	if (v->combine_func)
-		crc_combine_test(test, v);
-}
-
 static __always_inline void
 crc_benchmark(struct kunit *test,
 	      u64 (*crc_func)(u64 crc, const u8 *p, size_t len))
 {
 	static const size_t lens_to_test[] = {

@@ -335,21 +304,15 @@ static void crc_t10dif_benchmark(struct kunit *test)
 static u64 crc32_le_wrapper(u64 crc, const u8 *p, size_t len)
 {
 	return crc32_le(crc, p, len);
 }
 
-static u64 crc32_le_combine_wrapper(u64 crc1, u64 crc2, size_t len2)
-{
-	return crc32_le_combine(crc1, crc2, len2);
-}
-
 static const struct crc_variant crc_variant_crc32_le = {
 	.bits = 32,
 	.le = true,
 	.poly = 0xedb88320,
 	.func = crc32_le_wrapper,
-	.combine_func = crc32_le_combine_wrapper,
 };
 
 static void crc32_le_test(struct kunit *test)
 {
 	crc_test(test, &crc_variant_crc32_le);