[PATCH net-next 07/10] lib/crc32: remove unused support for CRC32C combination
From: Eric Biggers <ebiggers@kernel.org>
Date: 2025-05-11 00:41:36
Also in:
linux-nvme, linux-rdma, linux-sctp, lkml
Subsystem:
crc library, library code, the rest · Maintainers:
Eric Biggers, Andrew Morton, Linus Torvalds
From: Eric Biggers <redacted> crc32c_combine() and crc32c_shift() are no longer used (except by the KUnit test that tests them), and their current implementation is very slow. Remove them. Signed-off-by: Eric Biggers <redacted> --- include/linux/crc32.h | 23 ----------------------- lib/crc32.c | 6 ------ lib/tests/crc_kunit.c | 6 ------ 3 files changed, 35 deletions(-)
diff --git a/include/linux/crc32.h b/include/linux/crc32.h
index 69c2e8bb3782..7f7d0be8a0ac 100644
--- a/include/linux/crc32.h
+++ b/include/linux/crc32.h@@ -74,33 +74,10 @@ 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; } -u32 crc32c_shift(u32 crc, size_t len); - -/** - * crc32c_combine - Combine two crc32c check values into one. For two sequences - * of bytes, seq1 and seq2 with lengths len1 and len2, crc32c() - * check values were calculated for each, crc1 and crc2. - * - * @crc1: crc32c of the first block - * @crc2: crc32c of the second block - * @len2: length of the second block - * - * Return: The crc32c() 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 crc32c() value of - * seq_full, then crc_full == crc32c_combine(crc1, crc2, len2) when - * crc_full was seeded with the same initializer as crc1, and crc2 seed - * was 0. See also crc_combine_test(). - */ -static inline u32 crc32c_combine(u32 crc1, u32 crc2, size_t len2) -{ - return crc32c_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: *
diff --git a/lib/crc32.c b/lib/crc32.c
index fddd424ff224..ade48bbb0083 100644
--- a/lib/crc32.c
+++ b/lib/crc32.c@@ -117,16 +117,10 @@ u32 crc32_le_shift(u32 crc, size_t len) { return crc32_generic_shift(crc, len, CRC32_POLY_LE); } EXPORT_SYMBOL(crc32_le_shift); -u32 crc32c_shift(u32 crc, size_t len) -{ - return crc32_generic_shift(crc, len, CRC32C_POLY_LE); -} -EXPORT_SYMBOL(crc32c_shift); - u32 crc32_be_base(u32 crc, const u8 *p, size_t len) { while (len--) crc = (crc << 8) ^ crc32table_be[(crc >> 24) ^ *p++]; return crc;
diff --git a/lib/tests/crc_kunit.c b/lib/tests/crc_kunit.c
index 585c48b65cef..064c2d581557 100644
--- a/lib/tests/crc_kunit.c
+++ b/lib/tests/crc_kunit.c@@ -389,21 +389,15 @@ static void crc32_be_benchmark(struct kunit *test) static u64 crc32c_wrapper(u64 crc, const u8 *p, size_t len) { return crc32c(crc, p, len); } -static u64 crc32c_combine_wrapper(u64 crc1, u64 crc2, size_t len2) -{ - return crc32c_combine(crc1, crc2, len2); -} - static const struct crc_variant crc_variant_crc32c = { .bits = 32, .le = true, .poly = 0x82f63b78, .func = crc32c_wrapper, - .combine_func = crc32c_combine_wrapper, }; static void crc32c_test(struct kunit *test) { crc_test(test, &crc_variant_crc32c);
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2.49.0