New upstream version 18.11-rc3
[deb_dpdk.git] / lib / librte_vhost / vhost_crypto.c
index 5472bea..dd01afc 100644 (file)
@@ -198,6 +198,7 @@ struct vhost_crypto {
        struct rte_hash *session_map;
        struct rte_mempool *mbuf_pool;
        struct rte_mempool *sess_pool;
+       struct rte_mempool *wb_pool;
 
        /** DPDK cryptodev ID */
        uint8_t cid;
@@ -215,13 +216,20 @@ struct vhost_crypto {
        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 vring_desc *wb_desc;
-       uint16_t wb_len;
+       struct vhost_crypto_writeback_data *wb;
+       struct rte_mempool *wb_pool;
        uint16_t desc_idx;
        uint16_t len;
        uint16_t zero_copy;
@@ -506,15 +514,29 @@ move_desc(struct vring_desc *head, struct vring_desc **cur_desc,
                left -= desc->len;
        }
 
-       if (unlikely(left > 0)) {
-               VC_LOG_ERR("Incorrect virtio descriptor");
+       if (unlikely(left > 0))
                return -1;
-       }
 
        *cur_desc = &head[desc->next];
        return 0;
 }
 
+static __rte_always_inline void *
+get_data_ptr(struct vhost_crypto_data_req *vc_req, struct vring_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 int
 copy_data(void *dst_data, struct vhost_crypto_data_req *vc_req,
                struct vring_desc **cur_desc, uint32_t size)
@@ -531,10 +553,8 @@ copy_data(void *dst_data, struct vhost_crypto_data_req *vc_req,
        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");
+       if (unlikely(!src || !dlen))
                return -1;
-       }
 
        rte_memcpy((uint8_t *)data, src, dlen);
        data += dlen;
@@ -609,73 +629,158 @@ copy_data(void *dst_data, struct vhost_crypto_data_req *vc_req,
        return 0;
 }
 
-static __rte_always_inline void *
-get_data_ptr(struct vhost_crypto_data_req *vc_req, struct vring_desc **cur_desc,
-               uint32_t size, uint8_t perm)
+static void
+write_back_data(struct vhost_crypto_data_req *vc_req)
 {
-       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;
+       struct vhost_crypto_writeback_data *wb_data = vc_req->wb, *wb_last;
+
+       while (wb_data) {
+               rte_prefetch0(wb_data->next);
+               rte_memcpy(wb_data->dst, wb_data->src, wb_data->len);
+               wb_last = wb_data;
+               wb_data = wb_data->next;
+               rte_mempool_put(vc_req->wb_pool, wb_last);
        }
+}
 
-       if (unlikely(move_desc(vc_req->head, cur_desc, size) < 0))
-               return NULL;
+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);
 
-       return data;
+       rte_mempool_put(mp, wb_data);
 }
 
-static int
-write_back_data(struct rte_crypto_op *op, struct vhost_crypto_data_req *vc_req)
+/**
+ * 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 struct vhost_crypto_writeback_data *
+prepare_write_back_data(struct vhost_crypto_data_req *vc_req,
+               struct vring_desc **cur_desc,
+               struct vhost_crypto_writeback_data **end_wb_data,
+               uint8_t *src,
+               uint32_t offset,
+               uint64_t write_back_len)
 {
-       struct rte_mbuf *mbuf = op->sym->m_dst;
-       struct vring_desc *head = vc_req->head;
-       struct vring_desc *desc = vc_req->wb_desc;
-       int left = vc_req->wb_len;
-       uint32_t to_write;
-       uint8_t *src_data = mbuf->buf_addr, *dst;
+       struct vhost_crypto_writeback_data *wb_data, *head;
+       struct vring_desc *desc = *cur_desc;
        uint64_t dlen;
+       uint8_t *dst;
+       int ret;
 
-       rte_prefetch0(&head[desc->next]);
-       to_write = RTE_MIN(desc->len, (uint32_t)left);
-       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");
-               return -1;
+       ret = rte_mempool_get(vc_req->wb_pool, (void **)&head);
+       if (unlikely(ret < 0)) {
+               VC_LOG_ERR("no memory");
+               goto error_exit;
        }
 
-       rte_memcpy(dst, src_data, to_write);
-       left -= to_write;
-       src_data += to_write;
+       wb_data = head;
 
-       while ((desc->flags & VRING_DESC_F_NEXT) && left > 0) {
-               desc = &head[desc->next];
-               rte_prefetch0(&head[desc->next]);
-               to_write = RTE_MIN(desc->len, (uint32_t)left);
+       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);
+               dst = IOVA_TO_VVA(uint8_t *, vc_req, desc->addr,
+                       &dlen, VHOST_ACCESS_RW) + offset;
                if (unlikely(!dst || dlen != desc->len)) {
                        VC_LOG_ERR("Failed to map descriptor");
-                       return -1;
+                       goto error_exit;
                }
 
-               rte_memcpy(dst, src_data, to_write);
-               left -= to_write;
-               src_data += to_write;
-       }
+               wb_data->dst = dst;
+               wb_data->len = desc->len - offset;
+               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;
+                       }
 
-       if (unlikely(left < 0)) {
-               VC_LOG_ERR("Incorrect virtio descriptor");
-               return -1;
+                       wb_data = wb_data->next;
+               } else
+                       wb_data->next = NULL;
+       } else
+               offset -= desc->len;
+
+       while (write_back_len) {
+               desc = &vc_req->head[desc->next];
+               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;
+               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;
        }
 
-       return 0;
+       *cur_desc = &vc_req->head[desc->next];
+
+       *end_wb_data = wb_data;
+
+       return head;
+
+error_exit:
+       if (head)
+               free_wb_data(head, vc_req->wb_pool);
+
+       return NULL;
 }
 
 static uint8_t
@@ -685,6 +790,7 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                struct vring_desc *cur_desc)
 {
        struct vring_desc *desc = cur_desc;
+       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 = 0;
@@ -703,16 +809,25 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        case RTE_VHOST_CRYPTO_ZERO_COPY_ENABLE:
                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,
-                               cipher->para.src_data_len, VHOST_ACCESS_RO);
+               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(vc_req->head, &desc,
+                               cipher->para.src_data_len) < 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;
+
                if (unlikely(cipher->para.src_data_len >
                                RTE_MBUF_DEFAULT_BUF_SIZE)) {
                        VC_LOG_ERR("Not enough space to do data copy");
@@ -743,24 +858,31 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        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,
-                               cipher->para.dst_data_len, VHOST_ACCESS_RW);
+               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,
+                               cipher->para.dst_data_len) < 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_desc = desc;
-               vc_req->wb_len = cipher->para.dst_data_len;
-               if (unlikely(move_desc(vc_req->head, &desc,
-                               vc_req->wb_len) < 0)) {
+               vc_req->wb = prepare_write_back_data(vc_req, &desc, &ewb,
+                               rte_pktmbuf_mtod(m_src, uint8_t *), 0,
+                               cipher->para.dst_data_len);
+               if (unlikely(vc_req->wb == NULL)) {
                        ret = VIRTIO_CRYPTO_ERR;
                        goto error_exit;
                }
+
                break;
        default:
                ret = VIRTIO_CRYPTO_BADMSG;
@@ -774,7 +896,7 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        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, INHDR_LEN, VHOST_ACCESS_WO);
+       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;
@@ -786,6 +908,9 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        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;
 }
@@ -796,7 +921,8 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                struct virtio_crypto_alg_chain_data_req *chain,
                struct vring_desc *cur_desc)
 {
-       struct vring_desc *desc = cur_desc;
+       struct vring_desc *desc = cur_desc, *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;
@@ -812,21 +938,30 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        }
 
        m_src->data_len = chain->para.src_data_len;
-       m_dst->data_len = chain->para.dst_data_len;
 
        switch (vcrypto->option) {
        case RTE_VHOST_CRYPTO_ZERO_COPY_ENABLE:
+               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,
-                               chain->para.src_data_len, VHOST_ACCESS_RO);
+               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(vc_req->head, &desc,
+                               chain->para.src_data_len) < 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;
+
                if (unlikely(chain->para.src_data_len >
                                RTE_MBUF_DEFAULT_BUF_SIZE)) {
                        VC_LOG_ERR("Not enough space to do data copy");
@@ -838,6 +973,7 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                        ret = VIRTIO_CRYPTO_BADMSG;
                        goto error_exit;
                }
+
                break;
        default:
                ret = VIRTIO_CRYPTO_BADMSG;
@@ -856,46 +992,70 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        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,
-                               chain->para.dst_data_len, VHOST_ACCESS_RW);
+               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) < 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,
-                               chain->para.hash_result_len, VHOST_ACCESS_RW);
+               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(vc_req->head, &desc,
+                               chain->para.hash_result_len) < 0)) {
+                       VC_LOG_ERR("Incorrect descriptor");
+                       ret = VIRTIO_CRYPTO_ERR;
+                       goto error_exit;
+               }
+
                break;
        case RTE_VHOST_CRYPTO_ZERO_COPY_DISABLE:
-               digest_offset = m_dst->data_len;
-               digest_addr = rte_pktmbuf_mtod_offset(m_dst, void *,
-                               digest_offset);
+               vc_req->wb = prepare_write_back_data(vc_req, &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);
+               if (unlikely(vc_req->wb == NULL)) {
+                       ret = VIRTIO_CRYPTO_ERR;
+                       goto error_exit;
+               }
 
-               vc_req->wb_desc = desc;
-               vc_req->wb_len = m_dst->data_len + chain->para.hash_result_len;
+               digest_offset = m_src->data_len;
+               digest_addr = rte_pktmbuf_mtod_offset(m_src, void *,
+                               digest_offset);
+               digest_desc = desc;
 
-               if (unlikely(move_desc(vc_req->head, &desc,
-                               chain->para.dst_data_len) < 0)) {
-                       ret = VIRTIO_CRYPTO_BADMSG;
+               /** create a wb_data for digest */
+               ewb->next = prepare_write_back_data(vc_req, &desc, &ewb2,
+                               digest_addr, 0, chain->para.hash_result_len);
+               if (unlikely(ewb->next == NULL)) {
+                       ret = VIRTIO_CRYPTO_ERR;
                        goto error_exit;
                }
 
-               if (unlikely(copy_data(digest_addr, vc_req, &desc,
+               if (unlikely(copy_data(digest_addr, vc_req, &digest_desc,
                                chain->para.hash_result_len)) < 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_dst,
+               op->sym->auth.digest.phys_addr = rte_pktmbuf_iova_offset(m_src,
                                digest_offset);
                break;
        default:
@@ -904,7 +1064,7 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        }
 
        /* record inhdr */
-       vc_req->inhdr = get_data_ptr(vc_req, &desc, INHDR_LEN, VHOST_ACCESS_WO);
+       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;
@@ -927,6 +1087,8 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        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;
 }
@@ -967,7 +1129,7 @@ vhost_crypto_process_one_req(struct vhost_crypto *vcrypto,
        vc_req->head = head;
        vc_req->zero_copy = vcrypto->option;
 
-       req = get_data_ptr(vc_req, &desc, sizeof(*req), VHOST_ACCESS_RO);
+       req = get_data_ptr(vc_req, desc, VHOST_ACCESS_RO);
        if (unlikely(req == NULL)) {
                switch (vcrypto->option) {
                case RTE_VHOST_CRYPTO_ZERO_COPY_ENABLE:
@@ -988,6 +1150,12 @@ vhost_crypto_process_one_req(struct vhost_crypto *vcrypto,
                        VC_LOG_ERR("Invalid option");
                        goto error_exit;
                }
+       } else {
+               if (unlikely(move_desc(vc_req->head, &desc,
+                               sizeof(*req)) < 0)) {
+                       VC_LOG_ERR("Incorrect descriptor");
+                       goto error_exit;
+               }
        }
 
        switch (req->header.opcode) {
@@ -1062,7 +1230,6 @@ vhost_crypto_finalize_one_request(struct rte_crypto_op *op,
        struct rte_mbuf *m_dst = op->sym->m_dst;
        struct vhost_crypto_data_req *vc_req = rte_mbuf_to_priv(m_src);
        uint16_t desc_idx;
-       int ret = 0;
 
        if (unlikely(!vc_req)) {
                VC_LOG_ERR("Failed to retrieve vc_req");
@@ -1077,19 +1244,18 @@ vhost_crypto_finalize_one_request(struct rte_crypto_op *op,
        if (unlikely(op->status != RTE_CRYPTO_OP_STATUS_SUCCESS))
                vc_req->inhdr->status = VIRTIO_CRYPTO_ERR;
        else {
-               if (vc_req->zero_copy == 0) {
-                       ret = write_back_data(op, vc_req);
-                       if (unlikely(ret != 0))
-                               vc_req->inhdr->status = VIRTIO_CRYPTO_ERR;
-               }
+               if (vc_req->zero_copy == 0)
+                       write_back_data(vc_req);
        }
 
        vc_req->vq->used->ring[desc_idx].id = desc_idx;
        vc_req->vq->used->ring[desc_idx].len = vc_req->len;
 
-       rte_mempool_put(m_dst->pool, (void *)m_dst);
        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;
 }
 
@@ -1186,6 +1352,18 @@ rte_vhost_crypto_create(int vid, uint8_t cryptodev_id,
                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;
@@ -1222,6 +1400,7 @@ rte_vhost_crypto_free(int vid)
 
        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;
@@ -1257,11 +1436,30 @@ rte_vhost_crypto_set_zero_copy(int vid, enum rte_vhost_crypto_zero_copy option)
        if (vcrypto->option == (uint8_t)option)
                return 0;
 
-       if (!(rte_mempool_full(vcrypto->mbuf_pool))) {
+       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;
@@ -1277,9 +1475,8 @@ rte_vhost_crypto_fetch_requests(int vid, uint32_t qid,
        struct vhost_virtqueue *vq;
        uint16_t avail_idx;
        uint16_t start_idx;
-       uint16_t required;
        uint16_t count;
-       uint16_t i;
+       uint16_t i = 0;
 
        if (unlikely(dev == NULL)) {
                VC_LOG_ERR("Invalid vid %i", vid);
@@ -1311,27 +1508,66 @@ rte_vhost_crypto_fetch_requests(int vid, uint32_t qid,
        /* for zero copy, we need 2 empty mbufs for src and dst, otherwise
         * we need only 1 mbuf as src and dst
         */
-       required = count * 2;
-       if (unlikely(rte_mempool_get_bulk(vcrypto->mbuf_pool, (void **)mbufs,
-                       required) < 0)) {
-               VC_LOG_ERR("Insufficient memory");
-               return -ENOMEM;
-       }
+       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 -ENOMEM;
+               }
 
-       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];
+               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;
+                       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, desc_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 -ENOMEM;
+               }
+
+               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, desc_idx)) < 0)
+                               break;
+               }
+
+               if (unlikely(i < count))
+                       rte_mempool_put_bulk(vcrypto->mbuf_pool,
+                                       (void **)&mbufs[i],
+                                       count - i);
+
+               break;
 
-               if (unlikely(vhost_crypto_process_one_req(vcrypto, vq, op, head,
-                               desc_idx)) < 0)
-                       break;
        }
 
        vq->last_used_idx += i;