text: /* SPDX-License-Identifier: BSD-3-Clause
   * Copyright(c) 2017-2018 Intel Corporation
   */
  #include <rte_malloc.h>
  #include <rte_hash.h>
  #include <rte_jhash.h>
  #include <rte_mbuf.h>
  #include <rte_cryptodev.h>
  
  #include "rte_vhost_crypto.h"
  #include "vhost.h"
  #include "vhost_user.h"
  #include "virtio_crypto.h"
  
  #define INHDR_LEN		(sizeof(struct virtio_crypto_inhdr))
  #define IV_OFFSET		(sizeof(struct rte_crypto_op) + \
  				sizeof(struct rte_crypto_sym_op))
  
  #ifdef RTE_LIBRTE_VHOST_DEBUG
  #define VC_LOG_ERR(fmt, args...)				\
  	RTE_LOG(ERR, USER1, "[%s] %s() line %u: " fmt "\n",	\
  		"Vhost-Crypto",	__func__, __LINE__, ## args)
  #define VC_LOG_INFO(fmt, args...)				\
  	RTE_LOG(INFO, USER1, "[%s] %s() line %u: " fmt "\n",	\
  		"Vhost-Crypto",	__func__, __LINE__, ## args)
  
  #define VC_LOG_DBG(fmt, args...)				\
  	RTE_LOG(DEBUG, USER1, "[%s] %s() line %u: " fmt "\n",	\
  		"Vhost-Crypto",	__func__, __LINE__, ## args)
  #else
  #define VC_LOG_ERR(fmt, args...)				\
  	RTE_LOG(ERR, USER1, "[VHOST-Crypto]: " fmt "\n", ## args)
  #define VC_LOG_INFO(fmt, args...)				\
  	RTE_LOG(INFO, USER1, "[VHOST-Crypto]: " fmt "\n", ## args)
  #define VC_LOG_DBG(fmt, args...)
  #endif
  
  #define VIRTIO_CRYPTO_FEATURES ((1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |	\
  		(1ULL << VIRTIO_RING_F_INDIRECT_DESC) |			\
  		(1ULL << VIRTIO_RING_F_EVENT_IDX) |			\
  		(1ULL << VIRTIO_NET_F_CTRL_VQ) |			\
  		(1ULL << VIRTIO_F_VERSION_1) |				\
  		(1ULL << VHOST_USER_F_PROTOCOL_FEATURES))
  
  #define IOVA_TO_VVA(t, r, a, l, p)					\
  	((t)(uintptr_t)vhost_iova_to_vva(r->dev, r->vq, a, l, p))
  
  /*
   * vhost_crypto_desc is used to copy original vring_desc to the local buffer
   * before processing (except the next index). The copy result will be an
   * array of vhost_crypto_desc elements that follows the sequence of original
   * vring_desc.next is arranged.
   */
  #define vhost_crypto_desc vring_desc
  
  static int
  cipher_algo_transform(uint32_t virtio_cipher_algo,
  		enum rte_crypto_cipher_algorithm *algo)
  {
  	switch (virtio_cipher_algo) {
  	case VIRTIO_CRYPTO_CIPHER_AES_CBC:
  		*algo = RTE_CRYPTO_CIPHER_AES_CBC;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_AES_CTR:
  		*algo = RTE_CRYPTO_CIPHER_AES_CTR;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_DES_ECB:
  		*algo = -VIRTIO_CRYPTO_NOTSUPP;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_DES_CBC:
  		*algo = RTE_CRYPTO_CIPHER_DES_CBC;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_3DES_ECB:
  		*algo = RTE_CRYPTO_CIPHER_3DES_ECB;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_3DES_CBC:
  		*algo = RTE_CRYPTO_CIPHER_3DES_CBC;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_3DES_CTR:
  		*algo = RTE_CRYPTO_CIPHER_3DES_CTR;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_KASUMI_F8:
  		*algo = RTE_CRYPTO_CIPHER_KASUMI_F8;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_SNOW3G_UEA2:
  		*algo = RTE_CRYPTO_CIPHER_SNOW3G_UEA2;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_AES_F8:
  		*algo = RTE_CRYPTO_CIPHER_AES_F8;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_AES_XTS:
  		*algo = RTE_CRYPTO_CIPHER_AES_XTS;
  		break;
  	case VIRTIO_CRYPTO_CIPHER_ZUC_EEA3:
  		*algo = RTE_CRYPTO_CIPHER_ZUC_EEA3;
  		break;
  	default:
  		return -VIRTIO_CRYPTO_BADMSG;
  		break;
  	}
  
  	return 0;
  }
  
  static int
  auth_algo_transform(uint32_t virtio_auth_algo,
  		enum rte_crypto_auth_algorithm *algo)
  {
  	switch (virtio_auth_algo) {
  	case VIRTIO_CRYPTO_NO_MAC:
  		*algo = RTE_CRYPTO_AUTH_NULL;
  		break;
  	case VIRTIO_CRYPTO_MAC_HMAC_MD5:
  		*algo = RTE_CRYPTO_AUTH_MD5_HMAC;
  		break;
  	case VIRTIO_CRYPTO_MAC_HMAC_SHA1:
  		*algo = RTE_CRYPTO_AUTH_SHA1_HMAC;
  		break;
  	case VIRTIO_CRYPTO_MAC_HMAC_SHA_224:
  		*algo = RTE_CRYPTO_AUTH_SHA224_HMAC;
  		break;
  	case VIRTIO_CRYPTO_MAC_HMAC_SHA_256:
  		*algo = RTE_CRYPTO_AUTH_SHA256_HMAC;
  		break;
  	case VIRTIO_CRYPTO_MAC_HMAC_SHA_384:
  		*algo = RTE_CRYPTO_AUTH_SHA384_HMAC;
  		break;
  	case VIRTIO_CRYPTO_MAC_HMAC_SHA_512:
  		*algo = RTE_CRYPTO_AUTH_SHA512_HMAC;
  		break;
  	case VIRTIO_CRYPTO_MAC_CMAC_AES:
  		*algo = RTE_CRYPTO_AUTH_AES_CMAC;
  		break;
  	case VIRTIO_CRYPTO_MAC_KASUMI_F9:
  		*algo = RTE_CRYPTO_AUTH_KASUMI_F9;
  		break;
  	case VIRTIO_CRYPTO_MAC_SNOW3G_UIA2:
  		*algo = RTE_CRYPTO_AUTH_SNOW3G_UIA2;
  		break;
  	case VIRTIO_CRYPTO_MAC_GMAC_AES:
  		*algo = RTE_CRYPTO_AUTH_AES_GMAC;
  		break;
  	case VIRTIO_CRYPTO_MAC_CBCMAC_AES:
  		*algo = RTE_CRYPTO_AUTH_AES_CBC_MAC;
  		break;
  	case VIRTIO_CRYPTO_MAC_XCBC_AES:
  		*algo = RTE_CRYPTO_AUTH_AES_XCBC_MAC;
  		break;
  	case VIRTIO_CRYPTO_MAC_CMAC_3DES:
  	case VIRTIO_CRYPTO_MAC_GMAC_TWOFISH:
  	case VIRTIO_CRYPTO_MAC_CBCMAC_KASUMI_F9:
  		return -VIRTIO_CRYPTO_NOTSUPP;
  	default:
  		return -VIRTIO_CRYPTO_BADMSG;
  	}
  
  	return 0;
  }
  
  static int get_iv_len(enum rte_crypto_cipher_algorithm algo)
  {
  	int len;
  
  	switch (algo) {
  	case RTE_CRYPTO_CIPHER_3DES_CBC:
  		len = 8;
  		break;
  	case RTE_CRYPTO_CIPHER_3DES_CTR:
  		len = 8;
  		break;
  	case RTE_CRYPTO_CIPHER_3DES_ECB:
  		len = 8;
  		break;
  	case RTE_CRYPTO_CIPHER_AES_CBC:
  		len = 16;
  		break;
  
  	/* TODO: add common algos */
  
  	default:
  		len = -1;
  		break;
  	}
  
  	return len;
  }
  
  /**
   * vhost_crypto struct is used to maintain a number of virtio_cryptos and
   * one DPDK crypto device that deals with all crypto workloads. It is declared
   * here and defined in vhost_crypto.c
   */
  struct vhost_crypto {
  	/** Used to lookup DPDK Cryptodev Session based on VIRTIO crypto
  	 *  session ID.
  	 */
  	struct rte_hash *session_map;
  	struct rte_mempool *mbuf_pool;
  	struct rte_mempool *sess_pool;
  	struct rte_mempool *sess_priv_pool;
  	struct rte_mempool *wb_pool;
  
  	/** DPDK cryptodev ID */
  	uint8_t cid;
  	uint16_t nb_qps;
  
  	uint64_t last_session_id;
  
  	uint64_t cache_session_id;
  	struct rte_cryptodev_sym_session *cache_session;
  	/** socket id for the device */
  	int socket_id;
  
  	struct virtio_net *dev;
  
  	uint8_t option;
  } __rte_cache_aligned;
  
  struct vhost_crypto_writeback_data {
  	uint8_t *src;
  	uint8_t *dst;
  	uint64_t len;
  	struct vhost_crypto_writeback_data *next;
  };
  
  struct vhost_crypto_data_req {
  	struct vring_desc *head;
  	struct virtio_net *dev;
  	struct virtio_crypto_inhdr *inhdr;
  	struct vhost_virtqueue *vq;
  	struct vhost_crypto_writeback_data *wb;
  	struct rte_mempool *wb_pool;
  	uint16_t desc_idx;
  	uint16_t len;
  	uint16_t zero_copy;
  };
  
  static int
  transform_cipher_param(struct rte_crypto_sym_xform *xform,
  		VhostUserCryptoSessionParam *param)
  {
  	int ret;
  
  	ret = cipher_algo_transform(param->cipher_algo, &xform->cipher.algo);
  	if (unlikely(ret < 0))
  		return ret;
  
  	if (param->cipher_key_len > VHOST_USER_CRYPTO_MAX_CIPHER_KEY_LENGTH) {
  		VC_LOG_DBG("Invalid cipher key length\n");
  		return -VIRTIO_CRYPTO_BADMSG;
  	}
  
  	xform->type = RTE_CRYPTO_SYM_XFORM_CIPHER;
  	xform->cipher.key.length = param->cipher_key_len;
  	if (xform->cipher.key.length > 0)
  		xform->cipher.key.data = param->cipher_key_buf;
  	if (param->dir == VIRTIO_CRYPTO_OP_ENCRYPT)
  		xform->cipher.op = RTE_CRYPTO_CIPHER_OP_ENCRYPT;
  	else if (param->dir == VIRTIO_CRYPTO_OP_DECRYPT)
  		xform->cipher.op = RTE_CRYPTO_CIPHER_OP_DECRYPT;
  	else {
  		VC_LOG_DBG("Bad operation type");
  		return -VIRTIO_CRYPTO_BADMSG;
  	}
  
  	ret = get_iv_len(xform->cipher.algo);
  	if (unlikely(ret < 0))
  		return ret;
  	xform->cipher.iv.length = (uint16_t)ret;
  	xform->cipher.iv.offset = IV_OFFSET;
  	return 0;
  }
  
  static int
  transform_chain_param(struct rte_crypto_sym_xform *xforms,
  		VhostUserCryptoSessionParam *param)
  {
  	struct rte_crypto_sym_xform *xform_cipher, *xform_auth;
  	int ret;
  
  	switch (param->chaining_dir) {
  	case VIRTIO_CRYPTO_SYM_ALG_CHAIN_ORDER_HASH_THEN_CIPHER:
  		xform_auth = xforms;
  		xform_cipher = xforms->next;
  		xform_cipher->cipher.op = RTE_CRYPTO_CIPHER_OP_DECRYPT;
  		xform_auth->auth.op = RTE_CRYPTO_AUTH_OP_VERIFY;
  		break;
  	case VIRTIO_CRYPTO_SYM_ALG_CHAIN_ORDER_CIPHER_THEN_HASH:
  		xform_cipher = xforms;
  		xform_auth = xforms->next;
  		xform_cipher->cipher.op = RTE_CRYPTO_CIPHER_OP_ENCRYPT;
  		xform_auth->auth.op = RTE_CRYPTO_AUTH_OP_GENERATE;
  		break;
  	default:
  		return -VIRTIO_CRYPTO_BADMSG;
  	}
  
  	/* cipher */
  	ret = cipher_algo_transform(param->cipher_algo,
  			&xform_cipher->cipher.algo);
  	if (unlikely(ret < 0))
  		return ret;
  
  	if (param->cipher_key_len > VHOST_USER_CRYPTO_MAX_CIPHER_KEY_LENGTH) {
  		VC_LOG_DBG("Invalid cipher key length\n");
  		return -VIRTIO_CRYPTO_BADMSG;
  	}
  
  	xform_cipher->type = RTE_CRYPTO_SYM_XFORM_CIPHER;
  	xform_cipher->cipher.key.length = param->cipher_key_len;
  	xform_cipher->cipher.key.data = param->cipher_key_buf;
  	ret = get_iv_len(xform_cipher->cipher.algo);
  	if (unlikely(ret < 0))
  		return ret;
  	xform_cipher->cipher.iv.length = (uint16_t)ret;
  	xform_cipher->cipher.iv.offset = IV_OFFSET;
  
  	/* auth */
  	xform_auth->type = RTE_CRYPTO_SYM_XFORM_AUTH;
  	ret = auth_algo_transform(param->hash_algo, &xform_auth->auth.algo);
  	if (unlikely(ret < 0))
  		return ret;
  
  	if (param->auth_key_len > VHOST_USER_CRYPTO_MAX_HMAC_KEY_LENGTH) {
  		VC_LOG_DBG("Invalid auth key length\n");
  		return -VIRTIO_CRYPTO_BADMSG;
  	}
  
  	xform_auth->auth.digest_length = param->digest_len;
  	xform_auth->auth.key.length = param->auth_key_len;
  	xform_auth->auth.key.data = param->auth_key_buf;
  
  	return 0;
  }
  
  static void
  vhost_crypto_create_sess(struct vhost_crypto *vcrypto,
  		VhostUserCryptoSessionParam *sess_param)
  {
  	struct rte_crypto_sym_xform xform1 = {0}, xform2 = {0};
  	struct rte_cryptodev_sym_session *session;
  	int ret;
  
  	switch (sess_param->op_type) {
  	case VIRTIO_CRYPTO_SYM_OP_NONE:
  	case VIRTIO_CRYPTO_SYM_OP_CIPHER:
  		ret = transform_cipher_param(&xform1, sess_param);
  		if (unlikely(ret)) {
  			VC_LOG_ERR("Error transform session msg (%i)", ret);
  			sess_param->session_id = ret;
  			return;
  		}
  		break;
  	case VIRTIO_CRYPTO_SYM_OP_ALGORITHM_CHAINING:
  		if (unlikely(sess_param->hash_mode !=
  				VIRTIO_CRYPTO_SYM_HASH_MODE_AUTH)) {
  			sess_param->session_id = -VIRTIO_CRYPTO_NOTSUPP;
  			VC_LOG_ERR("Error transform session message (%i)",
  					-VIRTIO_CRYPTO_NOTSUPP);
  			return;
  		}
  
  		xform1.next = &xform2;
  
  		ret = transform_chain_param(&xform1, sess_param);
  		if (unlikely(ret)) {
  			VC_LOG_ERR("Error transform session message (%i)", ret);
  			sess_param->session_id = ret;
  			return;
  		}
  
  		break;
  	default:
  		VC_LOG_ERR("Algorithm not yet supported");
  		sess_param->session_id = -VIRTIO_CRYPTO_NOTSUPP;
  		return;
  	}
  
  	session = rte_cryptodev_sym_session_create(vcrypto->sess_pool);
  	if (!session) {
  		VC_LOG_ERR("Failed to create session");
  		sess_param->session_id = -VIRTIO_CRYPTO_ERR;
  		return;
  	}
  
  	if (rte_cryptodev_sym_session_init(vcrypto->cid, session, &xform1,
  			vcrypto->sess_priv_pool) < 0) {
  		VC_LOG_ERR("Failed to initialize session");
  		sess_param->session_id = -VIRTIO_CRYPTO_ERR;
  		return;
  	}
  
  	/* insert hash to map */
  	if (rte_hash_add_key_data(vcrypto->session_map,
  			&vcrypto->last_session_id, session) < 0) {
  		VC_LOG_ERR("Failed to insert session to hash table");
  
  		if (rte_cryptodev_sym_session_clear(vcrypto->cid, session) < 0)
  			VC_LOG_ERR("Failed to clear session");
  		else {
  			if (rte_cryptodev_sym_session_free(session) < 0)
  				VC_LOG_ERR("Failed to free session");
  		}
  		sess_param->session_id = -VIRTIO_CRYPTO_ERR;
  		return;
  	}
  
  	VC_LOG_INFO("Session %"PRIu64" created for vdev %i.",
  			vcrypto->last_session_id, vcrypto->dev->vid);
  
  	sess_param->session_id = vcrypto->last_session_id;
  	vcrypto->last_session_id++;
  }
  
  static int
  vhost_crypto_close_sess(struct vhost_crypto *vcrypto, uint64_t session_id)
  {
  	struct rte_cryptodev_sym_session *session;
  	uint64_t sess_id = session_id;
  	int ret;
  
  	ret = rte_hash_lookup_data(vcrypto->session_map, &sess_id,
  			(void **)&session);
  
  	if (unlikely(ret < 0)) {
  		VC_LOG_ERR("Failed to delete session %"PRIu64".", session_id);
  		return -VIRTIO_CRYPTO_INVSESS;
  	}
  
  	if (rte_cryptodev_sym_session_clear(vcrypto->cid, session) < 0) {
  		VC_LOG_DBG("Failed to clear session");
  		return -VIRTIO_CRYPTO_ERR;
  	}
  
  	if (rte_cryptodev_sym_session_free(session) < 0) {
  		VC_LOG_DBG("Failed to free session");
  		return -VIRTIO_CRYPTO_ERR;
  	}
  
  	if (rte_hash_del_key(vcrypto->session_map, &sess_id) < 0) {
  		VC_LOG_DBG("Failed to delete session from hash table.");
  		return -VIRTIO_CRYPTO_ERR;
  	}
  
  	VC_LOG_INFO("Session %"PRIu64" deleted for vdev %i.", sess_id,
  			vcrypto->dev->vid);
  
  	return 0;
  }
  
  static enum rte_vhost_msg_result
  vhost_crypto_msg_post_handler(int vid, void *msg)
  {
  	struct virtio_net *dev = get_device(vid);
  	struct vhost_crypto *vcrypto;
  	VhostUserMsg *vmsg = msg;
  	enum rte_vhost_msg_result ret = RTE_VHOST_MSG_RESULT_OK;
  
  	if (dev == NULL) {
  		VC_LOG_ERR("Invalid vid %i", vid);
  		return RTE_VHOST_MSG_RESULT_ERR;
  	}
  
  	vcrypto = dev->extern_data;
  	if (vcrypto == NULL) {
  		VC_LOG_ERR("Cannot find required data, is it initialized?");
  		return RTE_VHOST_MSG_RESULT_ERR;
  	}
  
  	switch (vmsg->request.master) {
  	case VHOST_USER_CRYPTO_CREATE_SESS:
  		vhost_crypto_create_sess(vcrypto,
  				&vmsg->payload.crypto_session);
  		vmsg->fd_num = 0;
  		ret = RTE_VHOST_MSG_RESULT_REPLY;
  		break;
  	case VHOST_USER_CRYPTO_CLOSE_SESS:
  		if (vhost_crypto_close_sess(vcrypto, vmsg->payload.u64))
  			ret = RTE_VHOST_MSG_RESULT_ERR;
  		break;
  	default:
  		ret = RTE_VHOST_MSG_RESULT_NOT_HANDLED;
  		break;
  	}
  
  	return ret;
  }
  
  static __rte_always_inline struct vhost_crypto_desc *
  find_write_desc(struct vhost_crypto_desc *head, struct vhost_crypto_desc *desc,
  		uint32_t max_n_descs)
  {
  	if (desc < head)
  		return NULL;
  
  	while (desc - head < (int)max_n_descs) {
  		if (desc->flags & VRING_DESC_F_WRITE)
  			return desc;
  		desc++;
  	}
  
  	return NULL;
  }
  
  static __rte_always_inline struct virtio_crypto_inhdr *
  reach_inhdr(struct vhost_crypto_data_req *vc_req,
  		struct vhost_crypto_desc *head,
  		uint32_t max_n_descs)
  {
  	struct virtio_crypto_inhdr *inhdr;
  	struct vhost_crypto_desc *last = head + (max_n_descs - 1);
  	uint64_t dlen = last->len;
  
  	if (unlikely(dlen != sizeof(*inhdr)))
  		return NULL;
  
  	inhdr = IOVA_TO_VVA(struct virtio_crypto_inhdr *, vc_req, last->addr,
  			&dlen, VHOST_ACCESS_WO);
  	if (unlikely(!inhdr || dlen != last->len))
  		return NULL;
  
  	return inhdr;
  }
  
  static __rte_always_inline int
  move_desc(struct vhost_crypto_desc *head,
  		struct vhost_crypto_desc **cur_desc,
  		uint32_t size, uint32_t max_n_descs)
  {
  	struct vhost_crypto_desc *desc = *cur_desc;
  	int left = size - desc->len;
  
  	while (desc->flags & VRING_DESC_F_NEXT && left > 0 &&
  			desc >= head &&
  			desc - head < (int)max_n_descs) {
  		desc++;
  		left -= desc->len;
  	}
  
  	if (unlikely(left > 0))
  		return -1;
  
  	if (unlikely(head - desc == (int)max_n_descs))
  		*cur_desc = NULL;
  	else
  		*cur_desc = desc + 1;
  
  	return 0;
  }
  
  static __rte_always_inline void *
  get_data_ptr(struct vhost_crypto_data_req *vc_req,
  		struct vhost_crypto_desc *cur_desc,
  		uint8_t perm)
  {
  	void *data;
  	uint64_t dlen = cur_desc->len;
  
  	data = IOVA_TO_VVA(void *, vc_req, cur_desc->addr, &dlen, perm);
  	if (unlikely(!data || dlen != cur_desc->len)) {
  		VC_LOG_ERR("Failed to map object");
  		return NULL;
  	}
  
  	return data;
  }
  
  static __rte_always_inline int
  copy_data(void *dst_data, struct vhost_crypto_data_req *vc_req,
  		struct vhost_crypto_desc *head,
  		struct vhost_crypto_desc **cur_desc,
  		uint32_t size, uint32_t max_n_descs)
  {
  	struct vhost_crypto_desc *desc = *cur_desc;
  	uint64_t remain, addr, dlen, len;
  	uint32_t to_copy;
  	uint8_t *data = dst_data;
  	uint8_t *src;
  	int left = size;
  
  	to_copy = RTE_MIN(desc->len, (uint32_t)left);
  	dlen = to_copy;
  	src = IOVA_TO_VVA(uint8_t *, vc_req, desc->addr, &dlen,
  			VHOST_ACCESS_RO);
  	if (unlikely(!src || !dlen))
  		return -1;
  
  	rte_memcpy((uint8_t *)data, src, dlen);
  	data += dlen;
  
  	if (unlikely(dlen < to_copy)) {
  		remain = to_copy - dlen;
  		addr = desc->addr + dlen;
  
  		while (remain) {
  			len = remain;
  			src = IOVA_TO_VVA(uint8_t *, vc_req, addr, &len,
  					VHOST_ACCESS_RO);
  			if (unlikely(!src || !len)) {
  				VC_LOG_ERR("Failed to map descriptor");
  				return -1;
  			}
  
  			rte_memcpy(data, src, len);
  			addr += len;
  			remain -= len;
  			data += len;
  		}
  	}
  
  	left -= to_copy;
  
  	while (desc >= head && desc - head < (int)max_n_descs && left) {
  		desc++;
  		to_copy = RTE_MIN(desc->len, (uint32_t)left);
  		dlen = to_copy;
  		src = IOVA_TO_VVA(uint8_t *, vc_req, desc->addr, &dlen,
  				VHOST_ACCESS_RO);
  		if (unlikely(!src || !dlen)) {
  			VC_LOG_ERR("Failed to map descriptor");
  			return -1;
  		}
  
  		rte_memcpy(data, src, dlen);
  		data += dlen;
  
  		if (unlikely(dlen < to_copy)) {
  			remain = to_copy - dlen;
  			addr = desc->addr + dlen;
  
  			while (remain) {
  				len = remain;
  				src = IOVA_TO_VVA(uint8_t *, vc_req, addr, &len,
  						VHOST_ACCESS_RO);
  				if (unlikely(!src || !len)) {
  					VC_LOG_ERR("Failed to map descriptor");
  					return -1;
  				}
  
  				rte_memcpy(data, src, len);
  				addr += len;
  				remain -= len;
  				data += len;
  			}
  		}
  
  		left -= to_copy;
  	}
  
  	if (unlikely(left > 0)) {
  		VC_LOG_ERR("Incorrect virtio descriptor");
  		return -1;
  	}
  
  	if (unlikely(desc - head == (int)max_n_descs))
  		*cur_desc = NULL;
  	else
  		*cur_desc = desc + 1;
  
  	return 0;
  }
  
  static void
  write_back_data(struct vhost_crypto_data_req *vc_req)
  {
  	struct vhost_crypto_writeback_data *wb_data = vc_req->wb, *wb_last;
  
  	while (wb_data) {
  		rte_memcpy(wb_data->dst, wb_data->src, wb_data->len);
  		memset(wb_data->src, 0, wb_data->len);
  		wb_last = wb_data;
  		wb_data = wb_data->next;
  		rte_mempool_put(vc_req->wb_pool, wb_last);
  	}
  }
  
  static void
  free_wb_data(struct vhost_crypto_writeback_data *wb_data,
  		struct rte_mempool *mp)
  {
  	while (wb_data->next != NULL)
  		free_wb_data(wb_data->next, mp);
  
  	rte_mempool_put(mp, wb_data);
  }
  
  /**
   * The function will allocate a vhost_crypto_writeback_data linked list
   * containing the source and destination data pointers for the write back
   * operation after dequeued from Cryptodev PMD queues.
   *
   * @param vc_req
   *   The vhost crypto data request pointer
   * @param cur_desc
   *   The pointer of the current in use descriptor pointer. The content of
   *   cur_desc is expected to be updated after the function execution.
   * @param end_wb_data
   *   The last write back data element to be returned. It is used only in cipher
   *   and hash chain operations.
   * @param src
   *   The source data pointer
   * @param offset
   *   The offset to both source and destination data. For source data the offset
   *   is the number of bytes between src and start point of cipher operation. For
   *   destination data the offset is the number of bytes from *cur_desc->addr
   *   to the point where the src will be written to.
   * @param write_back_len
   *   The size of the write back length.
   * @return
   *   The pointer to the start of the write back data linked list.
   */
  static __rte_always_inline struct vhost_crypto_writeback_data *
  prepare_write_back_data(struct vhost_crypto_data_req *vc_req,
  		struct vhost_crypto_desc *head_desc,
  		struct vhost_crypto_desc **cur_desc,
  		struct vhost_crypto_writeback_data **end_wb_data,
  		uint8_t *src,
  		uint32_t offset,
  		uint64_t write_back_len,
  		uint32_t max_n_descs)
  {
  	struct vhost_crypto_writeback_data *wb_data, *head;
  	struct vhost_crypto_desc *desc = *cur_desc;
  	uint64_t dlen;
  	uint8_t *dst;
  	int ret;
  
  	ret = rte_mempool_get(vc_req->wb_pool, (void **)&head);
  	if (unlikely(ret < 0)) {
  		VC_LOG_ERR("no memory");
  		goto error_exit;
  	}
  
  	wb_data = head;
  
  	if (likely(desc->len > offset)) {
  		wb_data->src = src + offset;
  		dlen = desc->len;
  		dst = IOVA_TO_VVA(uint8_t *, vc_req, desc->addr,
  			&dlen, VHOST_ACCESS_RW);
  		if (unlikely(!dst || dlen != desc->len)) {
  			VC_LOG_ERR("Failed to map descriptor");
  			goto error_exit;
  		}
  
  		wb_data->dst = dst + offset;
  		wb_data->len = RTE_MIN(dlen - offset, write_back_len);
  		write_back_len -= wb_data->len;
  		src += offset + wb_data->len;
  		offset = 0;
  
  		if (unlikely(write_back_len)) {
  			ret = rte_mempool_get(vc_req->wb_pool,
  					(void **)&(wb_data->next));
  			if (unlikely(ret < 0)) {
  				VC_LOG_ERR("no memory");
  				goto error_exit;
  			}
  
  			wb_data = wb_data->next;
  		} else
  			wb_data->next = NULL;
  	} else
  		offset -= desc->len;
  
  	while (write_back_len &&
  			desc >= head_desc &&
  			desc - head_desc < (int)max_n_descs) {
  		desc++;
  		if (unlikely(!(desc->flags & VRING_DESC_F_WRITE))) {
  			VC_LOG_ERR("incorrect descriptor");
  			goto error_exit;
  		}
  
  		if (desc->len <= offset) {
  			offset -= desc->len;
  			continue;
  		}
  
  		dlen = desc->len;
  		dst = IOVA_TO_VVA(uint8_t *, vc_req, desc->addr, &dlen,
  				VHOST_ACCESS_RW) + offset;
  		if (unlikely(dst == NULL || dlen != desc->len)) {
  			VC_LOG_ERR("Failed to map descriptor");
  			goto error_exit;
  		}
  
  		wb_data->src = src + offset;
  		wb_data->dst = dst;
  		wb_data->len = RTE_MIN(desc->len - offset, write_back_len);
  		write_back_len -= wb_data->len;
  		src += wb_data->len;
  		offset = 0;
  
  		if (write_back_len) {
  			ret = rte_mempool_get(vc_req->wb_pool,
  					(void **)&(wb_data->next));
  			if (unlikely(ret < 0)) {
  				VC_LOG_ERR("no memory");
  				goto error_exit;
  			}
  
  			wb_data = wb_data->next;
  		} else
  			wb_data->next = NULL;
  	}
  
  	if (unlikely(desc - head_desc == (int)max_n_descs))
  		*cur_desc = NULL;
  	else
  		*cur_desc = desc + 1;
  
  	*end_wb_data = wb_data;
  
  	return head;
  
  error_exit:
  	if (head)
  		free_wb_data(head, vc_req->wb_pool);
  
  	return NULL;
  }
  
  static __rte_always_inline uint8_t
  vhost_crypto_check_cipher_request(struct virtio_crypto_cipher_data_req *req)
  {
  	if (likely((req->para.iv_len <= VHOST_CRYPTO_MAX_IV_LEN) &&
  		(req->para.src_data_len <= RTE_MBUF_DEFAULT_BUF_SIZE) &&
  		(req->para.dst_data_len >= req->para.src_data_len) &&
  		(req->para.dst_data_len <= RTE_MBUF_DEFAULT_BUF_SIZE)))
  		return VIRTIO_CRYPTO_OK;
  	return VIRTIO_CRYPTO_BADMSG;
  }
  
  static __rte_always_inline uint8_t
  prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
  		struct vhost_crypto_data_req *vc_req,
  		struct virtio_crypto_cipher_data_req *cipher,
  		struct vhost_crypto_desc *head,
  		uint32_t max_n_descs)
  {
  	struct vhost_crypto_desc *desc = head;
  	struct vhost_crypto_writeback_data *ewb = NULL;
  	struct rte_mbuf *m_src = op->sym->m_src, *m_dst = op->sym->m_dst;
  	uint8_t *iv_data = rte_crypto_op_ctod_offset(op, uint8_t *, IV_OFFSET);
  	uint8_t ret = vhost_crypto_check_cipher_request(cipher);
  
  	if (unlikely(ret != VIRTIO_CRYPTO_OK))
  		goto error_exit;
  
  	/* prepare */
  	/* iv */
  	if (unlikely(copy_data(iv_data, vc_req, head, &desc,
  			cipher->para.iv_len, max_n_descs))) {
  		ret = VIRTIO_CRYPTO_BADMSG;
  		goto error_exit;
  	}
  
  	switch (vcrypto->option) {
  	case RTE_VHOST_CRYPTO_ZERO_COPY_ENABLE:
  		m_src->data_len = cipher->para.src_data_len;
  		m_src->buf_iova = gpa_to_hpa(vcrypto->dev, desc->addr,
  				cipher->para.src_data_len);
  		m_src->buf_addr = get_data_ptr(vc_req, desc, VHOST_ACCESS_RO);
  		if (unlikely(m_src->buf_iova == 0 ||
  				m_src->buf_addr == NULL)) {
  			VC_LOG_ERR("zero_copy may fail due to cross page data");
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		if (unlikely(move_desc(head, &desc, cipher->para.src_data_len,
  				max_n_descs) < 0)) {
  			VC_LOG_ERR("Incorrect descriptor");
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		break;
  	case RTE_VHOST_CRYPTO_ZERO_COPY_DISABLE:
  		vc_req->wb_pool = vcrypto->wb_pool;
  		m_src->data_len = cipher->para.src_data_len;
  		if (unlikely(copy_data(rte_pktmbuf_mtod(m_src, uint8_t *),
  				vc_req, head, &desc, cipher->para.src_data_len,
  				max_n_descs) < 0)) {
  			ret = VIRTIO_CRYPTO_BADMSG;
  			goto error_exit;
  		}
  		break;
  	default:
  		ret = VIRTIO_CRYPTO_BADMSG;
  		goto error_exit;
  	}
  
  	/* dst */
  	desc = find_write_desc(head, desc, max_n_descs);
  	if (unlikely(!desc)) {
  		VC_LOG_ERR("Cannot find write location");
  		ret = VIRTIO_CRYPTO_BADMSG;
  		goto error_exit;
  	}
  
  	switch (vcrypto->option) {
  	case RTE_VHOST_CRYPTO_ZERO_COPY_ENABLE:
  		m_dst->buf_iova = gpa_to_hpa(vcrypto->dev,
  				desc->addr, cipher->para.dst_data_len);
  		m_dst->buf_addr = get_data_ptr(vc_req, desc, VHOST_ACCESS_RW);
  		if (unlikely(m_dst->buf_iova == 0 || m_dst->buf_addr == NULL)) {
  			VC_LOG_ERR("zero_copy may fail due to cross page data");
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		if (unlikely(move_desc(head, &desc, cipher->para.dst_data_len,
  				max_n_descs) < 0)) {
  			VC_LOG_ERR("Incorrect descriptor");
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		m_dst->data_len = cipher->para.dst_data_len;
  		break;
  	case RTE_VHOST_CRYPTO_ZERO_COPY_DISABLE:
  		vc_req->wb = prepare_write_back_data(vc_req, head, &desc, &ewb,
  				rte_pktmbuf_mtod(m_src, uint8_t *), 0,
  				cipher->para.dst_data_len, max_n_descs);
  		if (unlikely(vc_req->wb == NULL)) {
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		break;
  	default:
  		ret = VIRTIO_CRYPTO_BADMSG;
  		goto error_exit;
  	}
  
  	/* src data */
  	op->type = RTE_CRYPTO_OP_TYPE_SYMMETRIC;
  	op->sess_type = RTE_CRYPTO_OP_WITH_SESSION;
  
  	op->sym->cipher.data.offset = 0;
  	op->sym->cipher.data.length = cipher->para.src_data_len;
  
  	vc_req->inhdr = get_data_ptr(vc_req, desc, VHOST_ACCESS_WO);
  	if (unlikely(vc_req->inhdr == NULL)) {
  		ret = VIRTIO_CRYPTO_BADMSG;
  		goto error_exit;
  	}
  
  	vc_req->inhdr->status = VIRTIO_CRYPTO_OK;
  	vc_req->len = cipher->para.dst_data_len + INHDR_LEN;
  
  	return 0;
  
  error_exit:
  	if (vc_req->wb)
  		free_wb_data(vc_req->wb, vc_req->wb_pool);
  
  	vc_req->len = INHDR_LEN;
  	return ret;
  }
  
  static __rte_always_inline uint8_t
  vhost_crypto_check_chain_request(struct virtio_crypto_alg_chain_data_req *req)
  {
  	if (likely((req->para.iv_len <= VHOST_CRYPTO_MAX_IV_LEN) &&
  		(req->para.src_data_len <= VHOST_CRYPTO_MAX_DATA_SIZE) &&
  		(req->para.dst_data_len >= req->para.src_data_len) &&
  		(req->para.dst_data_len <= VHOST_CRYPTO_MAX_DATA_SIZE) &&
  		(req->para.cipher_start_src_offset <
  			VHOST_CRYPTO_MAX_DATA_SIZE) &&
  		(req->para.len_to_cipher <= VHOST_CRYPTO_MAX_DATA_SIZE) &&
  		(req->para.hash_start_src_offset <
  			VHOST_CRYPTO_MAX_DATA_SIZE) &&
  		(req->para.len_to_hash <= VHOST_CRYPTO_MAX_DATA_SIZE) &&
  		(req->para.cipher_start_src_offset + req->para.len_to_cipher <=
  			req->para.src_data_len) &&
  		(req->para.hash_start_src_offset + req->para.len_to_hash <=
  			req->para.src_data_len) &&
  		(req->para.dst_data_len + req->para.hash_result_len <=
  			VHOST_CRYPTO_MAX_DATA_SIZE)))
  		return VIRTIO_CRYPTO_OK;
  	return VIRTIO_CRYPTO_BADMSG;
  }
  
  static __rte_always_inline uint8_t
  prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
  		struct vhost_crypto_data_req *vc_req,
  		struct virtio_crypto_alg_chain_data_req *chain,
  		struct vhost_crypto_desc *head,
  		uint32_t max_n_descs)
  {
  	struct vhost_crypto_desc *desc = head, *digest_desc;
  	struct vhost_crypto_writeback_data *ewb = NULL, *ewb2 = NULL;
  	struct rte_mbuf *m_src = op->sym->m_src, *m_dst = op->sym->m_dst;
  	uint8_t *iv_data = rte_crypto_op_ctod_offset(op, uint8_t *, IV_OFFSET);
  	uint32_t digest_offset;
  	void *digest_addr;
  	uint8_t ret = vhost_crypto_check_chain_request(chain);
  
  	if (unlikely(ret != VIRTIO_CRYPTO_OK))
  		goto error_exit;
  
  	/* prepare */
  	/* iv */
  	if (unlikely(copy_data(iv_data, vc_req, head, &desc,
  			chain->para.iv_len, max_n_descs) < 0)) {
  		ret = VIRTIO_CRYPTO_BADMSG;
  		goto error_exit;
  	}
  
  	switch (vcrypto->option) {
  	case RTE_VHOST_CRYPTO_ZERO_COPY_ENABLE:
  		m_src->data_len = chain->para.src_data_len;
  		m_dst->data_len = chain->para.dst_data_len;
  
  		m_src->buf_iova = gpa_to_hpa(vcrypto->dev, desc->addr,
  				chain->para.src_data_len);
  		m_src->buf_addr = get_data_ptr(vc_req, desc, VHOST_ACCESS_RO);
  		if (unlikely(m_src->buf_iova == 0 || m_src->buf_addr == NULL)) {
  			VC_LOG_ERR("zero_copy may fail due to cross page data");
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		if (unlikely(move_desc(head, &desc, chain->para.src_data_len,
  				max_n_descs) < 0)) {
  			VC_LOG_ERR("Incorrect descriptor");
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  		break;
  	case RTE_VHOST_CRYPTO_ZERO_COPY_DISABLE:
  		vc_req->wb_pool = vcrypto->wb_pool;
  		m_src->data_len = chain->para.src_data_len;
  		if (unlikely(copy_data(rte_pktmbuf_mtod(m_src, uint8_t *),
  				vc_req, head, &desc, chain->para.src_data_len,
  				max_n_descs) < 0)) {
  			ret = VIRTIO_CRYPTO_BADMSG;
  			goto error_exit;
  		}
  
  		break;
  	default:
  		ret = VIRTIO_CRYPTO_BADMSG;
  		goto error_exit;
  	}
  
  	/* dst */
  	desc = find_write_desc(head, desc, max_n_descs);
  	if (unlikely(!desc)) {
  		VC_LOG_ERR("Cannot find write location");
  		ret = VIRTIO_CRYPTO_BADMSG;
  		goto error_exit;
  	}
  
  	switch (vcrypto->option) {
  	case RTE_VHOST_CRYPTO_ZERO_COPY_ENABLE:
  		m_dst->buf_iova = gpa_to_hpa(vcrypto->dev,
  				desc->addr, chain->para.dst_data_len);
  		m_dst->buf_addr = get_data_ptr(vc_req, desc, VHOST_ACCESS_RW);
  		if (unlikely(m_dst->buf_iova == 0 || m_dst->buf_addr == NULL)) {
  			VC_LOG_ERR("zero_copy may fail due to cross page data");
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		if (unlikely(move_desc(vc_req->head, &desc,
  				chain->para.dst_data_len, max_n_descs) < 0)) {
  			VC_LOG_ERR("Incorrect descriptor");
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		op->sym->auth.digest.phys_addr = gpa_to_hpa(vcrypto->dev,
  				desc->addr, chain->para.hash_result_len);
  		op->sym->auth.digest.data = get_data_ptr(vc_req, desc,
  				VHOST_ACCESS_RW);
  		if (unlikely(op->sym->auth.digest.phys_addr == 0)) {
  			VC_LOG_ERR("zero_copy may fail due to cross page data");
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		if (unlikely(move_desc(head, &desc,
  				chain->para.hash_result_len,
  				max_n_descs) < 0)) {
  			VC_LOG_ERR("Incorrect descriptor");
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		break;
  	case RTE_VHOST_CRYPTO_ZERO_COPY_DISABLE:
  		vc_req->wb = prepare_write_back_data(vc_req, head, &desc, &ewb,
  				rte_pktmbuf_mtod(m_src, uint8_t *),
  				chain->para.cipher_start_src_offset,
  				chain->para.dst_data_len -
  					chain->para.cipher_start_src_offset,
  				max_n_descs);
  		if (unlikely(vc_req->wb == NULL)) {
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		digest_desc = desc;
  		digest_offset = m_src->data_len;
  		digest_addr = rte_pktmbuf_mtod_offset(m_src, void *,
  				digest_offset);
  
  		/** create a wb_data for digest */
  		ewb->next = prepare_write_back_data(vc_req, head, &desc,
  				&ewb2, digest_addr, 0,
  				chain->para.hash_result_len, max_n_descs);
  		if (unlikely(ewb->next == NULL)) {
  			ret = VIRTIO_CRYPTO_ERR;
  			goto error_exit;
  		}
  
  		if (unlikely(copy_data(digest_addr, vc_req, head, &digest_desc,
  				chain->para.hash_result_len,
  				max_n_descs) < 0)) {
  			ret = VIRTIO_CRYPTO_BADMSG;
  			goto error_exit;
  		}
  
  		op->sym->auth.digest.data = digest_addr;
  		op->sym->auth.digest.phys_addr = rte_pktmbuf_iova_offset(m_src,
  				digest_offset);
  		break;
  	default:
  		ret = VIRTIO_CRYPTO_BADMSG;
  		goto error_exit;
  	}
  
  	/* record inhdr */
  	vc_req->inhdr = get_data_ptr(vc_req, desc, VHOST_ACCESS_WO);
  	if (unlikely(vc_req->inhdr == NULL)) {
  		ret = VIRTIO_CRYPTO_BADMSG;
  		goto error_exit;
  	}
  
  	vc_req->inhdr->status = VIRTIO_CRYPTO_OK;
  
  	op->type = RTE_CRYPTO_OP_TYPE_SYMMETRIC;
  	op->sess_type = RTE_CRYPTO_OP_WITH_SESSION;
  
  	op->sym->cipher.data.offset = chain->para.cipher_start_src_offset;
  	op->sym->cipher.data.length = chain->para.src_data_len -
  			chain->para.cipher_start_src_offset;
  
  	op->sym->auth.data.offset = chain->para.hash_start_src_offset;
  	op->sym->auth.data.length = chain->para.len_to_hash;
  
  	vc_req->len = chain->para.dst_data_len + chain->para.hash_result_len +
  			INHDR_LEN;
  	return 0;
  
  error_exit:
  	if (vc_req->wb)
  		free_wb_data(vc_req->wb, vc_req->wb_pool);
  	vc_req->len = INHDR_LEN;
  	return ret;
  }
  
  /**
   * Process on descriptor
   */
  static __rte_always_inline int
  vhost_crypto_process_one_req(struct vhost_crypto *vcrypto,
  		struct vhost_virtqueue *vq, struct rte_crypto_op *op,
  		struct vring_desc *head, struct vhost_crypto_desc *descs,
  		uint16_t desc_idx)
  {
  	struct vhost_crypto_data_req *vc_req = rte_mbuf_to_priv(op->sym->m_src);
  	struct rte_cryptodev_sym_session *session;
  	struct virtio_crypto_op_data_req req;
  	struct virtio_crypto_inhdr *inhdr;
  	struct vhost_crypto_desc *desc = descs;
  	struct vring_desc *src_desc;
  	uint64_t session_id;
  	uint64_t dlen;
  	uint32_t nb_descs = 0, max_n_descs, i;
  	int err;
  
  	vc_req->desc_idx = desc_idx;
  	vc_req->dev = vcrypto->dev;
  	vc_req->vq = vq;
  
  	if (unlikely((head->flags & VRING_DESC_F_INDIRECT) == 0)) {
  		VC_LOG_ERR("Invalid descriptor");
  		return -1;
  	}
  
  	dlen = head->len;
  	src_desc = IOVA_TO_VVA(struct vring_desc *, vc_req, head->addr,
  			&dlen, VHOST_ACCESS_RO);
  	if (unlikely(!src_desc || dlen != head->len)) {
  		VC_LOG_ERR("Invalid descriptor");
  		return -1;
  	}
  	head = src_desc;
  
  	nb_descs = max_n_descs = dlen / sizeof(struct vring_desc);
  	if (unlikely(nb_descs > VHOST_CRYPTO_MAX_N_DESC || nb_descs == 0)) {
  		err = VIRTIO_CRYPTO_ERR;
  		VC_LOG_ERR("Cannot process num of descriptors %u", nb_descs);
  		if (nb_descs > 0) {
  			struct vring_desc *inhdr_desc = head;
  			while (inhdr_desc->flags & VRING_DESC_F_NEXT) {
  				if (inhdr_desc->next >= max_n_descs)
  					return -1;
  				inhdr_desc = &head[inhdr_desc->next];
  			}
  			if (inhdr_desc->len != sizeof(*inhdr))
  				return -1;
  			inhdr = IOVA_TO_VVA(struct virtio_crypto_inhdr *,
  					vc_req, inhdr_desc->addr, &dlen,
  					VHOST_ACCESS_WO);
  			if (unlikely(!inhdr || dlen != inhdr_desc->len))
  				return -1;
  			inhdr->status = VIRTIO_CRYPTO_ERR;
  			return -1;
  		}
  	}
  
  	/* copy descriptors to local variable */
  	for (i = 0; i < max_n_descs; i++) {
  		desc->addr = src_desc->addr;
  		desc->len = src_desc->len;
  		desc->flags = src_desc->flags;
  		desc++;
  		if (unlikely((src_desc->flags & VRING_DESC_F_NEXT) == 0))
  			break;
  		if (unlikely(src_desc->next >= max_n_descs)) {
  			err = VIRTIO_CRYPTO_BADMSG;
  			VC_LOG_ERR("Invalid descriptor");
  			goto error_exit;
  		}
  		src_desc = &head[src_desc->next];
  	}
  
  	vc_req->head = head;
  	vc_req->zero_copy = vcrypto->option;
  
  	nb_descs = desc - descs;
  	desc = descs;
  
  	if (unlikely(desc->len < sizeof(req))) {
  		err = VIRTIO_CRYPTO_BADMSG;
  		VC_LOG_ERR("Invalid descriptor");
  		goto error_exit;
  	}
  
  	if (unlikely(copy_data(&req, vc_req, descs, &desc, sizeof(req),
  			max_n_descs) < 0)) {
  		err = VIRTIO_CRYPTO_BADMSG;
  		VC_LOG_ERR("Invalid descriptor");
  		goto error_exit;
  	}
  
  	/* desc is advanced by 1 now */
  	max_n_descs -= 1;
  
  	switch (req.header.opcode) {
  	case VIRTIO_CRYPTO_CIPHER_ENCRYPT:
  	case VIRTIO_CRYPTO_CIPHER_DECRYPT:
  		session_id = req.header.session_id;
  
  		/* one branch to avoid unnecessary table lookup */
  		if (vcrypto->cache_session_id != session_id) {
  			err = rte_hash_lookup_data(vcrypto->session_map,
  					&session_id, (void **)&session);
  			if (unlikely(err < 0)) {
  				err = VIRTIO_CRYPTO_ERR;
  				VC_LOG_ERR("Failed to find session %"PRIu64,
  						session_id);
  				goto error_exit;
  			}
  
  			vcrypto->cache_session = session;
  			vcrypto->cache_session_id = session_id;
  		}
  
  		session = vcrypto->cache_session;
  
  		err = rte_crypto_op_attach_sym_session(op, session);
  		if (unlikely(err < 0)) {
  			err = VIRTIO_CRYPTO_ERR;
  			VC_LOG_ERR("Failed to attach session to op");
  			goto error_exit;
  		}
  
  		switch (req.u.sym_req.op_type) {
  		case VIRTIO_CRYPTO_SYM_OP_NONE:
  			err = VIRTIO_CRYPTO_NOTSUPP;
  			break;
  		case VIRTIO_CRYPTO_SYM_OP_CIPHER:
  			err = prepare_sym_cipher_op(vcrypto, op, vc_req,
  					&req.u.sym_req.u.cipher, desc,
  					max_n_descs);
  			break;
  		case VIRTIO_CRYPTO_SYM_OP_ALGORITHM_CHAINING:
  			err = prepare_sym_chain_op(vcrypto, op, vc_req,
  					&req.u.sym_req.u.chain, desc,
  					max_n_descs);
  			break;
  		}
  		if (unlikely(err != 0)) {
  			VC_LOG_ERR("Failed to process sym request");
  			goto error_exit;
  		}
  		break;
  	default:
  		err = VIRTIO_CRYPTO_ERR;
  		VC_LOG_ERR("Unsupported symmetric crypto request type %u",
  				req.header.opcode);
  		goto error_exit;
  	}
  
  	return 0;
  
  error_exit:
  
  	inhdr = reach_inhdr(vc_req, descs, max_n_descs);
  	if (likely(inhdr != NULL))
  		inhdr->status = (uint8_t)err;
  
  	return -1;
  }
  
  static __rte_always_inline struct vhost_virtqueue *
  vhost_crypto_finalize_one_request(struct rte_crypto_op *op,
  		struct vhost_virtqueue *old_vq)
  {
  	struct rte_mbuf *m_src = op->sym->m_src;
  	struct rte_mbuf *m_dst = op->sym->m_dst;
  	struct vhost_crypto_data_req *vc_req = rte_mbuf_to_priv(m_src);
  	struct vhost_virtqueue *vq = vc_req->vq;
  	uint16_t used_idx = vc_req->desc_idx, desc_idx;
  
  	if (unlikely(!vc_req)) {
  		VC_LOG_ERR("Failed to retrieve vc_req");
  		return NULL;
  	}
  
  	if (old_vq && (vq != old_vq))
  		return vq;
  
  	if (unlikely(op->status != RTE_CRYPTO_OP_STATUS_SUCCESS))
  		vc_req->inhdr->status = VIRTIO_CRYPTO_ERR;
  	else {
  		if (vc_req->zero_copy == 0)
  			write_back_data(vc_req);
  	}
  
  	desc_idx = vq->avail->ring[used_idx];
  	vq->used->ring[desc_idx].id = vq->avail->ring[desc_idx];
  	vq->used->ring[desc_idx].len = vc_req->len;
  
  	rte_mempool_put(m_src->pool, (void *)m_src);
  
  	if (m_dst)
  		rte_mempool_put(m_dst->pool, (void *)m_dst);
  
  	return vc_req->vq;
  }
  
  static __rte_always_inline uint16_t
  vhost_crypto_complete_one_vm_requests(struct rte_crypto_op **ops,
  		uint16_t nb_ops, int *callfd)
  {
  	uint16_t processed = 1;
  	struct vhost_virtqueue *vq, *tmp_vq;
  
  	if (unlikely(nb_ops == 0))
  		return 0;
  
  	vq = vhost_crypto_finalize_one_request(ops[0], NULL);
  	if (unlikely(vq == NULL))
  		return 0;
  	tmp_vq = vq;
  
  	while ((processed < nb_ops)) {
  		tmp_vq = vhost_crypto_finalize_one_request(ops[processed],
  				tmp_vq);
  
  		if (unlikely(vq != tmp_vq))
  			break;
  
  		processed++;
  	}
  
  	*callfd = vq->callfd;
  
  	*(volatile uint16_t *)&vq->used->idx += processed;
  
  	return processed;
  }
  
  int
  rte_vhost_crypto_driver_start(const char *path)
  {
  	uint64_t protocol_features;
  	int ret;
  
  	ret = rte_vhost_driver_set_features(path, VIRTIO_CRYPTO_FEATURES);
  	if (ret)
  		return -1;
  
  	ret = rte_vhost_driver_get_protocol_features(path, &protocol_features);
  	if (ret)
  		return -1;
  	protocol_features |= (1ULL << VHOST_USER_PROTOCOL_F_CONFIG);
  	ret = rte_vhost_driver_set_protocol_features(path, protocol_features);
  	if (ret)
  		return -1;
  
  	return rte_vhost_driver_start(path);
  }
  
  int
  rte_vhost_crypto_create(int vid, uint8_t cryptodev_id,
  		struct rte_mempool *sess_pool,
  		struct rte_mempool *sess_priv_pool,
  		int socket_id)
  {
  	struct virtio_net *dev = get_device(vid);
  	struct rte_hash_parameters params = {0};
  	struct vhost_crypto *vcrypto;
  	char name[128];
  	int ret;
  
  	if (!dev) {
  		VC_LOG_ERR("Invalid vid %i", vid);
  		return -EINVAL;
  	}
  
  	vcrypto = rte_zmalloc_socket(NULL, sizeof(*vcrypto),
  			RTE_CACHE_LINE_SIZE, socket_id);
  	if (!vcrypto) {
  		VC_LOG_ERR("Insufficient memory");
  		return -ENOMEM;
  	}
  
  	vcrypto->sess_pool = sess_pool;
  	vcrypto->sess_priv_pool = sess_priv_pool;
  	vcrypto->cid = cryptodev_id;
  	vcrypto->cache_session_id = UINT64_MAX;
  	vcrypto->last_session_id = 1;
  	vcrypto->dev = dev;
  	vcrypto->option = RTE_VHOST_CRYPTO_ZERO_COPY_DISABLE;
  
  	snprintf(name, 127, "HASH_VHOST_CRYPT_%u", (uint32_t)vid);
  	params.name = name;
  	params.entries = VHOST_CRYPTO_SESSION_MAP_ENTRIES;
  	params.hash_func = rte_jhash;
  	params.key_len = sizeof(uint64_t);
  	params.socket_id = socket_id;
  	vcrypto->session_map = rte_hash_create(&params);
  	if (!vcrypto->session_map) {
  		VC_LOG_ERR("Failed to creath session map");
  		ret = -ENOMEM;
  		goto error_exit;
  	}
  
  	snprintf(name, 127, "MBUF_POOL_VM_%u", (uint32_t)vid);
  	vcrypto->mbuf_pool = rte_pktmbuf_pool_create(name,
  			VHOST_CRYPTO_MBUF_POOL_SIZE, 512,
  			sizeof(struct vhost_crypto_data_req),
  			VHOST_CRYPTO_MAX_DATA_SIZE + RTE_PKTMBUF_HEADROOM,
  			rte_socket_id());
  	if (!vcrypto->mbuf_pool) {
  		VC_LOG_ERR("Failed to creath mbuf pool");
  		ret = -ENOMEM;
  		goto error_exit;
  	}
  
  	snprintf(name, 127, "WB_POOL_VM_%u", (uint32_t)vid);
  	vcrypto->wb_pool = rte_mempool_create(name,
  			VHOST_CRYPTO_MBUF_POOL_SIZE,
  			sizeof(struct vhost_crypto_writeback_data),
  			128, 0, NULL, NULL, NULL, NULL,
  			rte_socket_id(), 0);
  	if (!vcrypto->wb_pool) {
  		VC_LOG_ERR("Failed to creath mempool");
  		ret = -ENOMEM;
  		goto error_exit;
  	}
  
  	dev->extern_data = vcrypto;
  	dev->extern_ops.pre_msg_handle = NULL;
  	dev->extern_ops.post_msg_handle = vhost_crypto_msg_post_handler;
  
  	return 0;
  
  error_exit:
  	if (vcrypto->session_map)
  		rte_hash_free(vcrypto->session_map);
  	if (vcrypto->mbuf_pool)
  		rte_mempool_free(vcrypto->mbuf_pool);
  
  	rte_free(vcrypto);
  
  	return ret;
  }
  
  int
  rte_vhost_crypto_free(int vid)
  {
  	struct virtio_net *dev = get_device(vid);
  	struct vhost_crypto *vcrypto;
  
  	if (unlikely(dev == NULL)) {
  		VC_LOG_ERR("Invalid vid %i", vid);
  		return -EINVAL;
  	}
  
  	vcrypto = dev->extern_data;
  	if (unlikely(vcrypto == NULL)) {
  		VC_LOG_ERR("Cannot find required data, is it initialized?");
  		return -ENOENT;
  	}
  
  	rte_hash_free(vcrypto->session_map);
  	rte_mempool_free(vcrypto->mbuf_pool);
  	rte_mempool_free(vcrypto->wb_pool);
  	rte_free(vcrypto);
  
  	dev->extern_data = NULL;
  	dev->extern_ops.pre_msg_handle = NULL;
  	dev->extern_ops.post_msg_handle = NULL;
  
  	return 0;
  }
  
  int
  rte_vhost_crypto_set_zero_copy(int vid, enum rte_vhost_crypto_zero_copy option)
  {
  	struct virtio_net *dev = get_device(vid);
  	struct vhost_crypto *vcrypto;
  
  	if (unlikely(dev == NULL)) {
  		VC_LOG_ERR("Invalid vid %i", vid);
  		return -EINVAL;
  	}
  
  	if (unlikely((uint32_t)option >=
  				RTE_VHOST_CRYPTO_MAX_ZERO_COPY_OPTIONS)) {
  		VC_LOG_ERR("Invalid option %i", option);
  		return -EINVAL;
  	}
  
  	vcrypto = (struct vhost_crypto *)dev->extern_data;
  	if (unlikely(vcrypto == NULL)) {
  		VC_LOG_ERR("Cannot find required data, is it initialized?");
  		return -ENOENT;
  	}
  
  	if (vcrypto->option == (uint8_t)option)
  		return 0;
  
  	if (!(rte_mempool_full(vcrypto->mbuf_pool)) ||
  			!(rte_mempool_full(vcrypto->wb_pool))) {
  		VC_LOG_ERR("Cannot update zero copy as mempool is not full");
  		return -EINVAL;
  	}
  
  	if (option == RTE_VHOST_CRYPTO_ZERO_COPY_DISABLE) {
  		char name[128];
  
  		snprintf(name, 127, "WB_POOL_VM_%u", (uint32_t)vid);
  		vcrypto->wb_pool = rte_mempool_create(name,
  				VHOST_CRYPTO_MBUF_POOL_SIZE,
  				sizeof(struct vhost_crypto_writeback_data),
  				128, 0, NULL, NULL, NULL, NULL,
  				rte_socket_id(), 0);
  		if (!vcrypto->wb_pool) {
  			VC_LOG_ERR("Failed to creath mbuf pool");
  			return -ENOMEM;
  		}
  	} else {
  		rte_mempool_free(vcrypto->wb_pool);
  		vcrypto->wb_pool = NULL;
  	}
  
  	vcrypto->option = (uint8_t)option;
  
  	return 0;
  }
  
  uint16_t
  rte_vhost_crypto_fetch_requests(int vid, uint32_t qid,
  		struct rte_crypto_op **ops, uint16_t nb_ops)
  {
  	struct rte_mbuf *mbufs[VHOST_CRYPTO_MAX_BURST_SIZE * 2];
  	struct vhost_crypto_desc descs[VHOST_CRYPTO_MAX_N_DESC];
  	struct virtio_net *dev = get_device(vid);
  	struct vhost_crypto *vcrypto;
  	struct vhost_virtqueue *vq;
  	uint16_t avail_idx;
  	uint16_t start_idx;
  	uint16_t count;
  	uint16_t i = 0;
  
  	if (unlikely(dev == NULL)) {
  		VC_LOG_ERR("Invalid vid %i", vid);
  		return 0;
  	}
  
  	if (unlikely(qid >= VHOST_MAX_QUEUE_PAIRS)) {
  		VC_LOG_ERR("Invalid qid %u", qid);
  		return 0;
  	}
  
  	vcrypto = (struct vhost_crypto *)dev->extern_data;
  	if (unlikely(vcrypto == NULL)) {
  		VC_LOG_ERR("Cannot find required data, is it initialized?");
  		return 0;
  	}
  
  	vq = dev->virtqueue[qid];
  
  	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
  	start_idx = vq->last_used_idx;
  	count = avail_idx - start_idx;
  	count = RTE_MIN(count, VHOST_CRYPTO_MAX_BURST_SIZE);
  	count = RTE_MIN(count, nb_ops);
  
  	if (unlikely(count == 0))
  		return 0;
  
  	/* for zero copy, we need 2 empty mbufs for src and dst, otherwise
  	 * we need only 1 mbuf as src and dst
  	 */
  	switch (vcrypto->option) {
  	case RTE_VHOST_CRYPTO_ZERO_COPY_ENABLE:
  		if (unlikely(rte_mempool_get_bulk(vcrypto->mbuf_pool,
  				(void **)mbufs, count * 2) < 0)) {
  			VC_LOG_ERR("Insufficient memory");
  			return 0;
  		}
  
  		for (i = 0; i < count; i++) {
  			uint16_t used_idx = (start_idx + i) & (vq->size - 1);
  			uint16_t desc_idx = vq->avail->ring[used_idx];
  			struct vring_desc *head = &vq->desc[desc_idx];
  			struct rte_crypto_op *op = ops[i];
  
  			op->sym->m_src = mbufs[i * 2];
  			op->sym->m_dst = mbufs[i * 2 + 1];
  			op->sym->m_src->data_off = 0;
  			op->sym->m_dst->data_off = 0;
  
  			if (unlikely(vhost_crypto_process_one_req(vcrypto, vq,
  					op, head, descs, used_idx) < 0))
  				break;
  		}
  
  		if (unlikely(i < count))
  			rte_mempool_put_bulk(vcrypto->mbuf_pool,
  					(void **)&mbufs[i * 2],
  					(count - i) * 2);
  
  		break;
  
  	case RTE_VHOST_CRYPTO_ZERO_COPY_DISABLE:
  		if (unlikely(rte_mempool_get_bulk(vcrypto->mbuf_pool,
  				(void **)mbufs, count) < 0)) {
  			VC_LOG_ERR("Insufficient memory");
  			return 0;
  		}
  
  		for (i = 0; i < count; i++) {
  			uint16_t used_idx = (start_idx + i) & (vq->size - 1);
  			uint16_t desc_idx = vq->avail->ring[used_idx];
  			struct vring_desc *head = &vq->desc[desc_idx];
  			struct rte_crypto_op *op = ops[i];
  
  			op->sym->m_src = mbufs[i];
  			op->sym->m_dst = NULL;
  			op->sym->m_src->data_off = 0;
  
  			if (unlikely(vhost_crypto_process_one_req(vcrypto, vq,
  					op, head, descs, desc_idx) < 0))
  				break;
  		}
  
  		if (unlikely(i < count))
  			rte_mempool_put_bulk(vcrypto->mbuf_pool,
  					(void **)&mbufs[i],
  					count - i);
  
  		break;
  
  	}
  
  	vq->last_used_idx += i;
  
  	return i;
  }
  
  uint16_t
  rte_vhost_crypto_finalize_requests(struct rte_crypto_op **ops,
  		uint16_t nb_ops, int *callfds, uint16_t *nb_callfds)
  {
  	struct rte_crypto_op **tmp_ops = ops;
  	uint16_t count = 0, left = nb_ops;
  	int callfd;
  	uint16_t idx = 0;
  
  	while (left) {
  		count = vhost_crypto_complete_one_vm_requests(tmp_ops, left,
  				&callfd);
  		if (unlikely(count == 0))
  			break;
  
  		tmp_ops = &tmp_ops[count];
  		left -= count;
  
  		callfds[idx++] = callfd;
  
  		if (unlikely(idx >= VIRTIO_CRYPTO_MAX_NUM_BURST_VQS)) {
  			VC_LOG_ERR("Too many vqs");
  			break;
  		}
  	}
  
  	*nb_callfds = idx;
  
  	return nb_ops - left;
  }
  