cregit-Linux how code gets into the kernel

Release 4.8 fs/xfs/libxfs/xfs_cksum.h

Directory: fs/xfs/libxfs
#ifndef _XFS_CKSUM_H

#define _XFS_CKSUM_H 1


#define XFS_CRC_SEED	(~(__uint32_t)0)

/*
 * Calculate the intermediate checksum for a buffer that has the CRC field
 * inside it.  The offset of the 32bit crc fields is passed as the
 * cksum_offset parameter.
 */

static inline __uint32_t xfs_start_cksum(char *buffer, size_t length, unsigned long cksum_offset) { __uint32_t zero = 0; __uint32_t crc; /* Calculate CRC up to the checksum. */ crc = crc32c(XFS_CRC_SEED, buffer, cksum_offset); /* Skip checksum field */ crc = crc32c(crc, &zero, sizeof(__u32)); /* Calculate the rest of the CRC. */ return crc32c(crc, &buffer[cksum_offset + sizeof(__be32)], length - (cksum_offset + sizeof(__be32))); }

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christoph hellwigchristoph hellwig83100.00%1100.00%
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/* * Convert the intermediate checksum to the final ondisk format. * * The CRC32c calculation uses LE format even on BE machines, but returns the * result in host endian format. Hence we need to byte swap it back to LE format * so that it is consistent on disk. */
static inline __le32 xfs_end_cksum(__uint32_t crc) { return ~cpu_to_le32(crc); }

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christoph hellwigchristoph hellwig17100.00%1100.00%
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/* * Helper to generate the checksum for a buffer. */
static inline void xfs_update_cksum(char *buffer, size_t length, unsigned long cksum_offset) { __uint32_t crc = xfs_start_cksum(buffer, length, cksum_offset); *(__le32 *)(buffer + cksum_offset) = xfs_end_cksum(crc); }

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christoph hellwigchristoph hellwig46100.00%1100.00%
Total46100.00%1100.00%

/* * Helper to verify the checksum for a buffer. */
static inline int xfs_verify_cksum(char *buffer, size_t length, unsigned long cksum_offset) { __uint32_t crc = xfs_start_cksum(buffer, length, cksum_offset); return *(__le32 *)(buffer + cksum_offset) == xfs_end_cksum(crc); }

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christoph hellwigchristoph hellwig47100.00%1100.00%
Total47100.00%1100.00%

#endif /* _XFS_CKSUM_H */

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PersonTokensPropCommitsCommitProp
christoph hellwigchristoph hellwig211100.00%1100.00%
Total211100.00%1100.00%
Directory: fs/xfs/libxfs
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