mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-08-05 16:54:27 +00:00
2374bf2386
Move the s390-optimized CRC code from arch/s390/lib/crc* into its new location in lib/crc/s390/, and wire it up in the new way. This new way of organizing the CRC code eliminates the need to artificially split the code for each CRC variant into separate arch and generic modules, enabling better inlining and dead code elimination. For more details, see "lib/crc: Prepare for arch-optimized code in subdirs of lib/crc/". Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: "Jason A. Donenfeld" <Jason@zx2c4.com> Link: https://lore.kernel.org/r/20250607200454.73587-10-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
67 lines
2.2 KiB
C
67 lines
2.2 KiB
C
// 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>
|
|
*/
|
|
|
|
#include <linux/cpufeature.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) \
|
|
static inline 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; \
|
|
}
|
|
|
|
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)
|
|
|
|
static inline u32 crc32_optimizations_arch(void)
|
|
{
|
|
if (cpu_has_vx()) {
|
|
return CRC32_LE_OPTIMIZATION |
|
|
CRC32_BE_OPTIMIZATION |
|
|
CRC32C_OPTIMIZATION;
|
|
}
|
|
return 0;
|
|
}
|