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authorLinus Torvalds <torvalds@linux-foundation.org>2025-05-26 13:32:06 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2025-05-26 13:32:06 -0700
commit15d90a5e5524532b7456a24f4626cf28c1629c4c (patch)
tree9f819198d724af6fd0c46fda0013a29ede2c16a0 /arch/s390/lib/crc32.c
parentMerge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux (diff)
parentlib/crc32: add SPDX license identifier (diff)
downloadwireguard-linux-15d90a5e5524532b7456a24f4626cf28c1629c4c.tar.xz
wireguard-linux-15d90a5e5524532b7456a24f4626cf28c1629c4c.zip
Merge tag 'crc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux
Pull CRC updates from Eric Biggers: "Cleanups for the kernel's CRC (cyclic redundancy check) code: - Use __ro_after_init where appropriate - Remove unnecessary static_key on s390 - Rename some source code files - Rename the crc32 and crc32c crypto API modules - Use subsys_initcall instead of arch_initcall - Restore maintainers for crc_kunit.c - Fold crc16_byte() into crc16.c - Add some SPDX license identifiers" * tag 'crc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: lib/crc32: add SPDX license identifier lib/crc16: unexport crc16_table and crc16_byte() w1: ds2406: use crc16() instead of crc16_byte() loop MAINTAINERS: add crc_kunit.c back to CRC LIBRARY lib/crc: make arch-optimized code use subsys_initcall crypto: crc32 - remove "generic" from file and module names x86/crc: drop "glue" from filenames sparc/crc: drop "glue" from filenames s390/crc: drop "glue" from filenames powerpc/crc: rename crc32-vpmsum_core.S to crc-vpmsum-template.S powerpc/crc: drop "glue" from filenames arm64/crc: drop "glue" from filenames arm/crc: drop "glue" from filenames s390/crc32: Remove no-op module init and exit functions s390/crc32: Remove have_vxrs static key lib/crc: make the CPU feature static keys __ro_after_init
Diffstat (limited to 'arch/s390/lib/crc32.c')
-rw-r--r--arch/s390/lib/crc32.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/s390/lib/crc32.c b/arch/s390/lib/crc32.c
new file mode 100644
index 000000000000..3c4b344417c1
--- /dev/null
+++ b/arch/s390/lib/crc32.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CRC-32 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 <asm/fpu.h>
+#include "crc32-vx.h"
+
+#define VX_MIN_LEN 64
+#define VX_ALIGNMENT 16L
+#define VX_ALIGN_MASK (VX_ALIGNMENT - 1)
+
+/*
+ * 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) \
+ u32 ___fname(u32 crc, const u8 *data, size_t datalen) \
+ { \
+ unsigned long prealign, aligned, remaining; \
+ DECLARE_KERNEL_FPU_ONSTACK16(vxstate); \
+ \
+ if (datalen < VX_MIN_LEN + VX_ALIGN_MASK || !cpu_has_vx()) \
+ return ___crc32_sw(crc, data, datalen); \
+ \
+ 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); \
+ } \
+ \
+ 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, KERNEL_VXR_LOW); \
+ \
+ if (remaining) \
+ crc = ___crc32_sw(crc, data + aligned, remaining); \
+ \
+ return crc; \
+ } \
+ EXPORT_SYMBOL(___fname);
+
+DEFINE_CRC32_VX(crc32_le_arch, crc32_le_vgfm_16, crc32_le_base)
+DEFINE_CRC32_VX(crc32_be_arch, crc32_be_vgfm_16, crc32_be_base)
+DEFINE_CRC32_VX(crc32c_arch, crc32c_le_vgfm_16, crc32c_base)
+
+u32 crc32_optimizations(void)
+{
+ if (cpu_has_vx()) {
+ return CRC32_LE_OPTIMIZATION |
+ CRC32_BE_OPTIMIZATION |
+ CRC32C_OPTIMIZATION;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(crc32_optimizations);
+
+MODULE_AUTHOR("Hendrik Brueckner <brueckner@linux.vnet.ibm.com>");
+MODULE_DESCRIPTION("CRC-32 algorithms using z/Architecture Vector Extension Facility");
+MODULE_LICENSE("GPL");