crc32.h

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/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef _LINUX_CRC32_H
#define _LINUX_CRC32_H
 
#include <linux/types.h>
#include <linux/bitrev.h>
 
u32 crc32_le(u32 crc, const void *p, size_t len);
 
/* This is just an alias for crc32_le(). */
static inline u32 crc32(u32 crc, const void *p, size_t len)
{
    return crc32_le(crc, p, len);
}
 
u32 crc32_be(u32 crc, const void *p, size_t len);
 
u32 crc32c(u32 crc, const void *p, size_t len);
 
/*
 * crc32_optimizations() returns flags that indicate which CRC32 library
 * functions are using architecture-specific optimizations.  Unlike
 * IS_ENABLED(CONFIG_CRC32_ARCH) it takes into account the different CRC32
 * variants and also whether any needed CPU features are available at runtime.
 */
#define CRC32_LE_OPTIMIZATION   BIT(0) /* crc32_le() is optimized */
#define CRC32_BE_OPTIMIZATION   BIT(1) /* crc32_be() is optimized */
#define CRC32C_OPTIMIZATION BIT(2) /* crc32c() is optimized */
#if IS_ENABLED(CONFIG_CRC32_ARCH)
u32 crc32_optimizations(void);
#else
static inline u32 crc32_optimizations(void) { return 0; }
#endif
 
/*
 * Helpers for hash table generation of ethernet nics:
 *
 * Ethernet sends the least significant bit of a byte first, thus crc32_le
 * is used. The output of crc32_le is bit reversed [most significant bit
 * is in bit nr 0], thus it must be reversed before use. Except for
 * nics that bit swap the result internally...
 */
#define ether_crc(length, data)    bitrev32(crc32_le(~0, data, length))
#define ether_crc_le(length, data) crc32_le(~0, data, length)
 
#endif /* _LINUX_CRC32_H */