fscrypto: use standard macros to compute length of fname ciphertext

#include <linux/ratelimit.h>

#include <linux/fscrypto.h>

static u32 size_round_up(size_t size, size_t blksize)

{

	return ((size + blksize - 1) / blksize) * blksize;

}

/**

 * fname_crypt_complete() - completion callback for filename crypto

 * @req: The asynchronous cipher request context

	if (iname->len <= 0 || iname->len > lim)

		return -EIO;

	ciphertext_len = (iname->len < FS_CRYPTO_BLOCK_SIZE) ?

					FS_CRYPTO_BLOCK_SIZE : iname->len;

	ciphertext_len = size_round_up(ciphertext_len, padding);

	ciphertext_len = (ciphertext_len > lim) ? lim : ciphertext_len;

	ciphertext_len = max(iname->len, (u32)FS_CRYPTO_BLOCK_SIZE);

	ciphertext_len = round_up(ciphertext_len, padding);

	ciphertext_len = min(ciphertext_len, lim);

	if (ciphertext_len <= sizeof(buf)) {

		workbuf = buf;

	if (ci)

		padding = 4 << (ci->ci_flags & FS_POLICY_FLAGS_PAD_MASK);

	if (ilen < FS_CRYPTO_BLOCK_SIZE)

		ilen = FS_CRYPTO_BLOCK_SIZE;

	return size_round_up(ilen, padding);

	ilen = max(ilen, (u32)FS_CRYPTO_BLOCK_SIZE);

	return round_up(ilen, padding);

}

EXPORT_SYMBOL(fscrypt_fname_encrypted_size);