text: #ifndef CRYPTO_HASH_H
  #define CRYPTO_HASH_H
  
  #include <linux/types.h>
  
  #define CRYPTO_HASH_SIZE_MAX	32
  
  void btrfs_hash_init(void);
  int hash_crc32c(const u8 *buf, size_t length, u8 *out);
  int hash_xxhash(const u8 *buf, size_t length, u8 *out);
  int hash_sha256(const u8 *buf, size_t length, u8 *out);
  
  u32 crc32c(u32 seed, const void * data, size_t len);
  
  /* Blake2B is not yet supported due to lack of library */
  
  #endif
  