BLK_CRYPTO_MAX_IV_SIZE
u8 bytes[BLK_CRYPTO_MAX_IV_SIZE];
blk_crypto_fallback_profile->max_dun_bytes_supported = BLK_CRYPTO_MAX_IV_SIZE;
BUG_ON(blk_crypto_modes[i].ivsize > BLK_CRYPTO_MAX_IV_SIZE);
BUILD_BUG_ON(FSCRYPT_MAX_IV_SIZE > BLK_CRYPTO_MAX_IV_SIZE);
memset(dun, 0, BLK_CRYPTO_MAX_IV_SIZE);
#define BLK_CRYPTO_DUN_ARRAY_SIZE (BLK_CRYPTO_MAX_IV_SIZE / sizeof(u64))