Merge tag 'io_uring-5.7-2020-05-22' of git://git.kernel.dk/linux-block

[thirdparty/linux.git] / drivers / crypto / chelsio / chcr_ktls.c

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (C) 2020 Chelsio Communications.  All rights reserved. */

#ifdef CONFIG_CHELSIO_TLS_DEVICE
#include <linux/highmem.h>
#include "chcr_ktls.h"
#include "clip_tbl.h"

static int chcr_init_tcb_fields(struct chcr_ktls_info *tx_info);
/*
 * chcr_ktls_save_keys: calculate and save crypto keys.
 * @tx_info - driver specific tls info.
 * @crypto_info - tls crypto information.
 * @direction - TX/RX direction.
 * return - SUCCESS/FAILURE.
 */
static int chcr_ktls_save_keys(struct chcr_ktls_info *tx_info,
                               struct tls_crypto_info *crypto_info,
                               enum tls_offload_ctx_dir direction)
{
        int ck_size, key_ctx_size, mac_key_size, keylen, ghash_size, ret;
        unsigned char ghash_h[TLS_CIPHER_AES_GCM_256_TAG_SIZE];
        struct tls12_crypto_info_aes_gcm_128 *info_128_gcm;
        struct ktls_key_ctx *kctx = &tx_info->key_ctx;
        struct crypto_cipher *cipher;
        unsigned char *key, *salt;

        switch (crypto_info->cipher_type) {
        case TLS_CIPHER_AES_GCM_128:
                info_128_gcm =
                        (struct tls12_crypto_info_aes_gcm_128 *)crypto_info;
                keylen = TLS_CIPHER_AES_GCM_128_KEY_SIZE;
                ck_size = CHCR_KEYCTX_CIPHER_KEY_SIZE_128;
                tx_info->salt_size = TLS_CIPHER_AES_GCM_128_SALT_SIZE;
                mac_key_size = CHCR_KEYCTX_MAC_KEY_SIZE_128;
                tx_info->iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
                tx_info->iv = be64_to_cpu(*(__be64 *)info_128_gcm->iv);

                ghash_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
                key = info_128_gcm->key;
                salt = info_128_gcm->salt;
                tx_info->record_no = *(u64 *)info_128_gcm->rec_seq;

                /* The SCMD fields used when encrypting a full TLS
                 * record. Its a one time calculation till the
                 * connection exists.
                 */
                tx_info->scmd0_seqno_numivs =
                        SCMD_SEQ_NO_CTRL_V(CHCR_SCMD_SEQ_NO_CTRL_64BIT) |
                        SCMD_CIPH_AUTH_SEQ_CTRL_F |
                        SCMD_PROTO_VERSION_V(CHCR_SCMD_PROTO_VERSION_TLS) |
                        SCMD_CIPH_MODE_V(CHCR_SCMD_CIPHER_MODE_AES_GCM) |
                        SCMD_AUTH_MODE_V(CHCR_SCMD_AUTH_MODE_GHASH) |
                        SCMD_IV_SIZE_V(TLS_CIPHER_AES_GCM_128_IV_SIZE >> 1) |
                        SCMD_NUM_IVS_V(1);

                /* keys will be sent inline. */
                tx_info->scmd0_ivgen_hdrlen = SCMD_KEY_CTX_INLINE_F;

                /* The SCMD fields used when encrypting a partial TLS
                 * record (no trailer and possibly a truncated payload).
                 */
                tx_info->scmd0_short_seqno_numivs =
                        SCMD_CIPH_AUTH_SEQ_CTRL_F |
                        SCMD_PROTO_VERSION_V(CHCR_SCMD_PROTO_VERSION_GENERIC) |
                        SCMD_CIPH_MODE_V(CHCR_SCMD_CIPHER_MODE_AES_CTR) |
                        SCMD_IV_SIZE_V(AES_BLOCK_LEN >> 1);

                tx_info->scmd0_short_ivgen_hdrlen =
                        tx_info->scmd0_ivgen_hdrlen | SCMD_AADIVDROP_F;

                break;

        default:
                pr_err("GCM: cipher type 0x%x not supported\n",
                       crypto_info->cipher_type);
                ret = -EINVAL;
                goto out;
        }

        key_ctx_size = CHCR_KTLS_KEY_CTX_LEN +
                       roundup(keylen, 16) + ghash_size;
        /* Calculate the H = CIPH(K, 0 repeated 16 times).
         * It will go in key context
         */
        cipher = crypto_alloc_cipher("aes", 0, 0);
        if (IS_ERR(cipher)) {
                ret = -ENOMEM;
                goto out;
        }

        ret = crypto_cipher_setkey(cipher, key, keylen);
        if (ret)
                goto out1;

        memset(ghash_h, 0, ghash_size);
        crypto_cipher_encrypt_one(cipher, ghash_h, ghash_h);

        /* fill the Key context */
        if (direction == TLS_OFFLOAD_CTX_DIR_TX) {
                kctx->ctx_hdr = FILL_KEY_CTX_HDR(ck_size,
                                                 mac_key_size,
                                                 key_ctx_size >> 4);
        } else {
                ret = -EINVAL;
                goto out1;
        }

        memcpy(kctx->salt, salt, tx_info->salt_size);
        memcpy(kctx->key, key, keylen);
        memcpy(kctx->key + keylen, ghash_h, ghash_size);
        tx_info->key_ctx_len = key_ctx_size;

out1:
        crypto_free_cipher(cipher);
out:
        return ret;
}

static int chcr_ktls_update_connection_state(struct chcr_ktls_info *tx_info,
                                             int new_state)
{
        /* This function can be called from both rx (interrupt context) and tx
         * queue contexts.
         */
        spin_lock_bh(&tx_info->lock);
        switch (tx_info->connection_state) {
        case KTLS_CONN_CLOSED:
                tx_info->connection_state = new_state;
                break;

        case KTLS_CONN_ACT_OPEN_REQ:
                /* only go forward if state is greater than current state. */
                if (new_state <= tx_info->connection_state)
                        break;
                /* update to the next state and also initialize TCB */
                tx_info->connection_state = new_state;
                /* FALLTHRU */
        case KTLS_CONN_ACT_OPEN_RPL:
                /* if we are stuck in this state, means tcb init might not
                 * received by HW, try sending it again.
                 */
                if (!chcr_init_tcb_fields(tx_info))
                        tx_info->connection_state = KTLS_CONN_SET_TCB_REQ;
                break;

        case KTLS_CONN_SET_TCB_REQ:
                /* only go forward if state is greater than current state. */
                if (new_state <= tx_info->connection_state)
                        break;
                /* update to the next state and check if l2t_state is valid  */
                tx_info->connection_state = new_state;
                /* FALLTHRU */
        case KTLS_CONN_SET_TCB_RPL:
                /* Check if l2t state is valid, then move to ready state. */
                if (cxgb4_check_l2t_valid(tx_info->l2te)) {
                        tx_info->connection_state = KTLS_CONN_TX_READY;
                        atomic64_inc(&tx_info->adap->chcr_stats.ktls_tx_ctx);
                }
                break;

        case KTLS_CONN_TX_READY:
                /* nothing to be done here */
                break;

        default:
                pr_err("unknown KTLS connection state\n");
                break;
        }
        spin_unlock_bh(&tx_info->lock);

        return tx_info->connection_state;
}
/*
 * chcr_ktls_act_open_req: creates TCB entry for ipv4 connection.
 * @sk - tcp socket.
 * @tx_info - driver specific tls info.
 * @atid - connection active tid.
 * return - send success/failure.
 */
static int chcr_ktls_act_open_req(struct sock *sk,
                                  struct chcr_ktls_info *tx_info,
                                  int atid)
{
        struct inet_sock *inet = inet_sk(sk);
        struct cpl_t6_act_open_req *cpl6;
        struct cpl_act_open_req *cpl;
        struct sk_buff *skb;
        unsigned int len;
        int qid_atid;
        u64 options;

        len = sizeof(*cpl6);
        skb = alloc_skb(len, GFP_KERNEL);
        if (unlikely(!skb))
                return -ENOMEM;
        /* mark it a control pkt */
        set_wr_txq(skb, CPL_PRIORITY_CONTROL, tx_info->port_id);

        cpl6 = __skb_put_zero(skb, len);
        cpl = (struct cpl_act_open_req *)cpl6;
        INIT_TP_WR(cpl6, 0);
        qid_atid = TID_QID_V(tx_info->rx_qid) |
                   TID_TID_V(atid);
        OPCODE_TID(cpl) = htonl(MK_OPCODE_TID(CPL_ACT_OPEN_REQ, qid_atid));
        cpl->local_port = inet->inet_sport;
        cpl->peer_port = inet->inet_dport;
        cpl->local_ip = inet->inet_rcv_saddr;
        cpl->peer_ip = inet->inet_daddr;

        /* fill first 64 bit option field. */
        options = TCAM_BYPASS_F | ULP_MODE_V(ULP_MODE_NONE) | NON_OFFLOAD_F |
                  SMAC_SEL_V(tx_info->smt_idx) | TX_CHAN_V(tx_info->tx_chan);
        cpl->opt0 = cpu_to_be64(options);

        /* next 64 bit option field. */
        options =
                TX_QUEUE_V(tx_info->adap->params.tp.tx_modq[tx_info->tx_chan]);
        cpl->opt2 = htonl(options);

        return cxgb4_l2t_send(tx_info->netdev, skb, tx_info->l2te);
}

/*
 * chcr_ktls_act_open_req6: creates TCB entry for ipv6 connection.
 * @sk - tcp socket.
 * @tx_info - driver specific tls info.
 * @atid - connection active tid.
 * return - send success/failure.
 */
static int chcr_ktls_act_open_req6(struct sock *sk,
                                   struct chcr_ktls_info *tx_info,
                                   int atid)
{
        struct inet_sock *inet = inet_sk(sk);
        struct cpl_t6_act_open_req6 *cpl6;
        struct cpl_act_open_req6 *cpl;
        struct sk_buff *skb;
        unsigned int len;
        int qid_atid;
        u64 options;

        len = sizeof(*cpl6);
        skb = alloc_skb(len, GFP_KERNEL);
        if (unlikely(!skb))
                return -ENOMEM;
        /* mark it a control pkt */
        set_wr_txq(skb, CPL_PRIORITY_CONTROL, tx_info->port_id);

        cpl6 = __skb_put_zero(skb, len);
        cpl = (struct cpl_act_open_req6 *)cpl6;
        INIT_TP_WR(cpl6, 0);
        qid_atid = TID_QID_V(tx_info->rx_qid) | TID_TID_V(atid);
        OPCODE_TID(cpl) = htonl(MK_OPCODE_TID(CPL_ACT_OPEN_REQ6, qid_atid));
        cpl->local_port = inet->inet_sport;
        cpl->peer_port = inet->inet_dport;
        cpl->local_ip_hi = *(__be64 *)&sk->sk_v6_rcv_saddr.in6_u.u6_addr8[0];
        cpl->local_ip_lo = *(__be64 *)&sk->sk_v6_rcv_saddr.in6_u.u6_addr8[8];
        cpl->peer_ip_hi = *(__be64 *)&sk->sk_v6_daddr.in6_u.u6_addr8[0];
        cpl->peer_ip_lo = *(__be64 *)&sk->sk_v6_daddr.in6_u.u6_addr8[8];

        /* first 64 bit option field. */
        options = TCAM_BYPASS_F | ULP_MODE_V(ULP_MODE_NONE) | NON_OFFLOAD_F |
                  SMAC_SEL_V(tx_info->smt_idx) | TX_CHAN_V(tx_info->tx_chan);
        cpl->opt0 = cpu_to_be64(options);
        /* next 64 bit option field. */
        options =
                TX_QUEUE_V(tx_info->adap->params.tp.tx_modq[tx_info->tx_chan]);
        cpl->opt2 = htonl(options);

        return cxgb4_l2t_send(tx_info->netdev, skb, tx_info->l2te);
}

/*
 * chcr_setup_connection:  create a TCB entry so that TP will form tcp packets.
 * @sk - tcp socket.
 * @tx_info - driver specific tls info.
 * return: NET_TX_OK/NET_XMIT_DROP
 */
static int chcr_setup_connection(struct sock *sk,
                                 struct chcr_ktls_info *tx_info)
{
        struct tid_info *t = &tx_info->adap->tids;
        int atid, ret = 0;

        atid = cxgb4_alloc_atid(t, tx_info);
        if (atid == -1)
                return -EINVAL;

        tx_info->atid = atid;
        tx_info->ip_family = sk->sk_family;

        if (sk->sk_family == AF_INET ||
            (sk->sk_family == AF_INET6 && !sk->sk_ipv6only &&
             ipv6_addr_type(&sk->sk_v6_daddr) == IPV6_ADDR_MAPPED)) {
                tx_info->ip_family = AF_INET;
                ret = chcr_ktls_act_open_req(sk, tx_info, atid);
        } else {
                tx_info->ip_family = AF_INET6;
                ret =
                cxgb4_clip_get(tx_info->netdev,
                               (const u32 *)&sk->sk_v6_rcv_saddr.in6_u.u6_addr8,
                               1);
                if (ret)
                        goto out;
                ret = chcr_ktls_act_open_req6(sk, tx_info, atid);
        }

        /* if return type is NET_XMIT_CN, msg will be sent but delayed, mark ret
         * success, if any other return type clear atid and return that failure.
         */
        if (ret) {
                if (ret == NET_XMIT_CN)
                        ret = 0;
                else
                        cxgb4_free_atid(t, atid);
                goto out;
        }

        /* update the connection state */
        chcr_ktls_update_connection_state(tx_info, KTLS_CONN_ACT_OPEN_REQ);
out:
        return ret;
}

/*
 * chcr_set_tcb_field: update tcb fields.
 * @tx_info - driver specific tls info.
 * @word - TCB word.
 * @mask - TCB word related mask.
 * @val - TCB word related value.
 * @no_reply - set 1 if not looking for TP response.
 */
static int chcr_set_tcb_field(struct chcr_ktls_info *tx_info, u16 word,
                              u64 mask, u64 val, int no_reply)
{
        struct cpl_set_tcb_field *req;
        struct sk_buff *skb;

        skb = alloc_skb(sizeof(struct cpl_set_tcb_field), GFP_ATOMIC);
        if (!skb)
                return -ENOMEM;

        req = (struct cpl_set_tcb_field *)__skb_put_zero(skb, sizeof(*req));
        INIT_TP_WR_CPL(req, CPL_SET_TCB_FIELD, tx_info->tid);
        req->reply_ctrl = htons(QUEUENO_V(tx_info->rx_qid) |
                                NO_REPLY_V(no_reply));
        req->word_cookie = htons(TCB_WORD_V(word));
        req->mask = cpu_to_be64(mask);
        req->val = cpu_to_be64(val);

        set_wr_txq(skb, CPL_PRIORITY_CONTROL, tx_info->port_id);
        return cxgb4_ofld_send(tx_info->netdev, skb);
}

/*
 * chcr_ktls_mark_tcb_close: mark tcb state to CLOSE
 * @tx_info - driver specific tls info.
 * return: NET_TX_OK/NET_XMIT_DROP.
 */
static int chcr_ktls_mark_tcb_close(struct chcr_ktls_info *tx_info)
{
        return chcr_set_tcb_field(tx_info, TCB_T_STATE_W,
                                  TCB_T_STATE_V(TCB_T_STATE_M),
                                  CHCR_TCB_STATE_CLOSED, 1);
}

/*
 * chcr_ktls_dev_del:  call back for tls_dev_del.
 * Remove the tid and l2t entry and close the connection.
 * it per connection basis.
 * @netdev - net device.
 * @tls_cts - tls context.
 * @direction - TX/RX crypto direction
 */
static void chcr_ktls_dev_del(struct net_device *netdev,
                              struct tls_context *tls_ctx,
                              enum tls_offload_ctx_dir direction)
{
        struct chcr_ktls_ofld_ctx_tx *tx_ctx =
                                chcr_get_ktls_tx_context(tls_ctx);
        struct chcr_ktls_info *tx_info = tx_ctx->chcr_info;
        struct sock *sk;

        if (!tx_info)
                return;
        sk = tx_info->sk;

        spin_lock(&tx_info->lock);
        tx_info->connection_state = KTLS_CONN_CLOSED;
        spin_unlock(&tx_info->lock);

        /* clear l2t entry */
        if (tx_info->l2te)
                cxgb4_l2t_release(tx_info->l2te);

        /* clear clip entry */
        if (tx_info->ip_family == AF_INET6)
                cxgb4_clip_release(netdev,
                                   (const u32 *)&sk->sk_v6_daddr.in6_u.u6_addr8,
                                   1);

        /* clear tid */
        if (tx_info->tid != -1) {
                /* clear tcb state and then release tid */
                chcr_ktls_mark_tcb_close(tx_info);
                cxgb4_remove_tid(&tx_info->adap->tids, tx_info->tx_chan,
                                 tx_info->tid, tx_info->ip_family);
        }

        atomic64_inc(&tx_info->adap->chcr_stats.ktls_tx_connection_close);
        kvfree(tx_info);
        tx_ctx->chcr_info = NULL;
}

/*
 * chcr_ktls_dev_add:  call back for tls_dev_add.
 * Create a tcb entry for TP. Also add l2t entry for the connection. And
 * generate keys & save those keys locally.
 * @netdev - net device.
 * @tls_cts - tls context.
 * @direction - TX/RX crypto direction
 * return: SUCCESS/FAILURE.
 */
static int chcr_ktls_dev_add(struct net_device *netdev, struct sock *sk,
                             enum tls_offload_ctx_dir direction,
                             struct tls_crypto_info *crypto_info,
                             u32 start_offload_tcp_sn)
{
        struct tls_context *tls_ctx = tls_get_ctx(sk);
        struct chcr_ktls_ofld_ctx_tx *tx_ctx;
        struct chcr_ktls_info *tx_info;
        struct dst_entry *dst;
        struct adapter *adap;
        struct port_info *pi;
        struct neighbour *n;
        u8 daaddr[16];
        int ret = -1;

        tx_ctx = chcr_get_ktls_tx_context(tls_ctx);

        pi = netdev_priv(netdev);
        adap = pi->adapter;
        if (direction == TLS_OFFLOAD_CTX_DIR_RX) {
                pr_err("not expecting for RX direction\n");
                ret = -EINVAL;
                goto out;
        }
        if (tx_ctx->chcr_info) {
                ret = -EINVAL;
                goto out;
        }

        tx_info = kvzalloc(sizeof(*tx_info), GFP_KERNEL);
        if (!tx_info) {
                ret = -ENOMEM;
                goto out;
        }

        spin_lock_init(&tx_info->lock);

        /* clear connection state */
        spin_lock(&tx_info->lock);
        tx_info->connection_state = KTLS_CONN_CLOSED;
        spin_unlock(&tx_info->lock);

        tx_info->sk = sk;
        /* initialize tid and atid to -1, 0 is a also a valid id. */
        tx_info->tid = -1;
        tx_info->atid = -1;

        tx_info->adap = adap;
        tx_info->netdev = netdev;
        tx_info->first_qset = pi->first_qset;
        tx_info->tx_chan = pi->tx_chan;
        tx_info->smt_idx = pi->smt_idx;
        tx_info->port_id = pi->port_id;

        tx_info->rx_qid = chcr_get_first_rx_qid(adap);
        if (unlikely(tx_info->rx_qid < 0))
                goto out2;

        tx_info->prev_seq = start_offload_tcp_sn;
        tx_info->tcp_start_seq_number = start_offload_tcp_sn;

        /* save crypto keys */
        ret = chcr_ktls_save_keys(tx_info, crypto_info, direction);
        if (ret < 0)
                goto out2;

        /* get peer ip */
        if (sk->sk_family == AF_INET ||
            (sk->sk_family == AF_INET6 && !sk->sk_ipv6only &&
             ipv6_addr_type(&sk->sk_v6_daddr) == IPV6_ADDR_MAPPED)) {
                memcpy(daaddr, &sk->sk_daddr, 4);
        } else {
                memcpy(daaddr, sk->sk_v6_daddr.in6_u.u6_addr8, 16);
        }

        /* get the l2t index */
        dst = sk_dst_get(sk);
        if (!dst) {
                pr_err("DST entry not found\n");
                goto out2;
        }
        n = dst_neigh_lookup(dst, daaddr);
        if (!n || !n->dev) {
                pr_err("neighbour not found\n");
                dst_release(dst);
                goto out2;
        }
        tx_info->l2te  = cxgb4_l2t_get(adap->l2t, n, n->dev, 0);

        neigh_release(n);
        dst_release(dst);

        if (!tx_info->l2te) {
                pr_err("l2t entry not found\n");
                goto out2;
        }

        tx_ctx->chcr_info = tx_info;

        /* create a filter and call cxgb4_l2t_send to send the packet out, which
         * will take care of updating l2t entry in hw if not already done.
         */
        ret = chcr_setup_connection(sk, tx_info);
        if (ret)
                goto out2;

        atomic64_inc(&adap->chcr_stats.ktls_tx_connection_open);
        return 0;
out2:
        kvfree(tx_info);
out:
        atomic64_inc(&adap->chcr_stats.ktls_tx_connection_fail);
        return ret;
}

static const struct tlsdev_ops chcr_ktls_ops = {
        .tls_dev_add = chcr_ktls_dev_add,
        .tls_dev_del = chcr_ktls_dev_del,
};

/*
 * chcr_enable_ktls:  add NETIF_F_HW_TLS_TX flag in all the ports.
 */
void chcr_enable_ktls(struct adapter *adap)
{
        struct net_device *netdev;
        int i;

        for_each_port(adap, i) {
                netdev = adap->port[i];
                netdev->features |= NETIF_F_HW_TLS_TX;
                netdev->hw_features |= NETIF_F_HW_TLS_TX;
                netdev->tlsdev_ops = &chcr_ktls_ops;
        }
}

/*
 * chcr_disable_ktls:  remove NETIF_F_HW_TLS_TX flag from all the ports.
 */
void chcr_disable_ktls(struct adapter *adap)
{
        struct net_device *netdev;
        int i;

        for_each_port(adap, i) {
                netdev = adap->port[i];
                netdev->features &= ~NETIF_F_HW_TLS_TX;
                netdev->hw_features &= ~NETIF_F_HW_TLS_TX;
                netdev->tlsdev_ops = NULL;
        }
}

/*
 * chcr_init_tcb_fields:  Initialize tcb fields to handle TCP seq number
 *                        handling.
 * @tx_info - driver specific tls info.
 * return: NET_TX_OK/NET_XMIT_DROP
 */
static int chcr_init_tcb_fields(struct chcr_ktls_info *tx_info)
{
        int  ret = 0;

        /* set tcb in offload and bypass */
        ret =
        chcr_set_tcb_field(tx_info, TCB_T_FLAGS_W,
                           TCB_T_FLAGS_V(TF_CORE_BYPASS_F | TF_NON_OFFLOAD_F),
                           TCB_T_FLAGS_V(TF_CORE_BYPASS_F), 1);
        if (ret)
                return ret;
        /* reset snd_una and snd_next fields in tcb */
        ret = chcr_set_tcb_field(tx_info, TCB_SND_UNA_RAW_W,
                                 TCB_SND_NXT_RAW_V(TCB_SND_NXT_RAW_M) |
                                 TCB_SND_UNA_RAW_V(TCB_SND_UNA_RAW_M),
                                 0, 1);
        if (ret)
                return ret;

        /* reset send max */
        ret = chcr_set_tcb_field(tx_info, TCB_SND_MAX_RAW_W,
                                 TCB_SND_MAX_RAW_V(TCB_SND_MAX_RAW_M),
                                 0, 1);
        if (ret)
                return ret;

        /* update l2t index and request for tp reply to confirm tcb is
         * initialised to handle tx traffic.
         */
        ret = chcr_set_tcb_field(tx_info, TCB_L2T_IX_W,
                                 TCB_L2T_IX_V(TCB_L2T_IX_M),
                                 TCB_L2T_IX_V(tx_info->l2te->idx), 0);
        return ret;
}

/*
 * chcr_ktls_cpl_act_open_rpl: connection reply received from TP.
 */
int chcr_ktls_cpl_act_open_rpl(struct adapter *adap, unsigned char *input)
{
        const struct cpl_act_open_rpl *p = (void *)input;
        struct chcr_ktls_info *tx_info = NULL;
        unsigned int atid, tid, status;
        struct tid_info *t;

        tid = GET_TID(p);
        status = AOPEN_STATUS_G(ntohl(p->atid_status));
        atid = TID_TID_G(AOPEN_ATID_G(ntohl(p->atid_status)));

        t = &adap->tids;
        tx_info = lookup_atid(t, atid);

        if (!tx_info || tx_info->atid != atid) {
                pr_err("tx_info or atid is not correct\n");
                return -1;
        }

        if (!status) {
                tx_info->tid = tid;
                cxgb4_insert_tid(t, tx_info, tx_info->tid, tx_info->ip_family);

                cxgb4_free_atid(t, atid);
                tx_info->atid = -1;
                /* update the connection state */
                chcr_ktls_update_connection_state(tx_info,
                                                  KTLS_CONN_ACT_OPEN_RPL);
        }
        return 0;
}

/*
 * chcr_ktls_cpl_set_tcb_rpl: TCB reply received from TP.
 */
int chcr_ktls_cpl_set_tcb_rpl(struct adapter *adap, unsigned char *input)
{
        const struct cpl_set_tcb_rpl *p = (void *)input;
        struct chcr_ktls_info *tx_info = NULL;
        struct tid_info *t;
        u32 tid;

        tid = GET_TID(p);

        t = &adap->tids;
        tx_info = lookup_tid(t, tid);
        if (!tx_info || tx_info->tid != tid) {
                pr_err("tx_info or atid is not correct\n");
                return -1;
        }
        /* update the connection state */
        chcr_ktls_update_connection_state(tx_info, KTLS_CONN_SET_TCB_RPL);
        return 0;
}

static void *__chcr_write_cpl_set_tcb_ulp(struct chcr_ktls_info *tx_info,
                                        u32 tid, void *pos, u16 word, u64 mask,
                                        u64 val, u32 reply)
{
        struct cpl_set_tcb_field_core *cpl;
        struct ulptx_idata *idata;
        struct ulp_txpkt *txpkt;

        /* ULP_TXPKT */
        txpkt = pos;
        txpkt->cmd_dest = htonl(ULPTX_CMD_V(ULP_TX_PKT) | ULP_TXPKT_DEST_V(0));
        txpkt->len = htonl(DIV_ROUND_UP(CHCR_SET_TCB_FIELD_LEN, 16));

        /* ULPTX_IDATA sub-command */
        idata = (struct ulptx_idata *)(txpkt + 1);
        idata->cmd_more = htonl(ULPTX_CMD_V(ULP_TX_SC_IMM));
        idata->len = htonl(sizeof(*cpl));
        pos = idata + 1;

        cpl = pos;
        /* CPL_SET_TCB_FIELD */
        OPCODE_TID(cpl) = htonl(MK_OPCODE_TID(CPL_SET_TCB_FIELD, tid));
        cpl->reply_ctrl = htons(QUEUENO_V(tx_info->rx_qid) |
                        NO_REPLY_V(!reply));
        cpl->word_cookie = htons(TCB_WORD_V(word));
        cpl->mask = cpu_to_be64(mask);
        cpl->val = cpu_to_be64(val);

        /* ULPTX_NOOP */
        idata = (struct ulptx_idata *)(cpl + 1);
        idata->cmd_more = htonl(ULPTX_CMD_V(ULP_TX_SC_NOOP));
        idata->len = htonl(0);
        pos = idata + 1;

        return pos;
}


/*
 * chcr_write_cpl_set_tcb_ulp: update tcb values.
 * TCB is responsible to create tcp headers, so all the related values
 * should be correctly updated.
 * @tx_info - driver specific tls info.
 * @q - tx queue on which packet is going out.
 * @tid - TCB identifier.
 * @pos - current index where should we start writing.
 * @word - TCB word.
 * @mask - TCB word related mask.
 * @val - TCB word related value.
 * @reply - set 1 if looking for TP response.
 * return - next position to write.
 */
static void *chcr_write_cpl_set_tcb_ulp(struct chcr_ktls_info *tx_info,
                                        struct sge_eth_txq *q, u32 tid,
                                        void *pos, u16 word, u64 mask,
                                        u64 val, u32 reply)
{
        int left = (void *)q->q.stat - pos;

        if (unlikely(left < CHCR_SET_TCB_FIELD_LEN)) {
                if (!left) {
                        pos = q->q.desc;
                } else {
                        u8 buf[48] = {0};

                        __chcr_write_cpl_set_tcb_ulp(tx_info, tid, buf, word,
                                                     mask, val, reply);

                        return chcr_copy_to_txd(buf, &q->q, pos,
                                                CHCR_SET_TCB_FIELD_LEN);
                }
        }

        pos = __chcr_write_cpl_set_tcb_ulp(tx_info, tid, pos, word,
                                           mask, val, reply);

        /* check again if we are at the end of the queue */
        if (left == CHCR_SET_TCB_FIELD_LEN)
                pos = q->q.desc;

        return pos;
}

/*
 * chcr_ktls_xmit_tcb_cpls: update tcb entry so that TP will create the header
 * with updated values like tcp seq, ack, window etc.
 * @tx_info - driver specific tls info.
 * @q - TX queue.
 * @tcp_seq
 * @tcp_ack
 * @tcp_win
 * return: NETDEV_TX_BUSY/NET_TX_OK.
 */
static int chcr_ktls_xmit_tcb_cpls(struct chcr_ktls_info *tx_info,
                                   struct sge_eth_txq *q, u64 tcp_seq,
                                   u64 tcp_ack, u64 tcp_win)
{
        bool first_wr = ((tx_info->prev_ack == 0) && (tx_info->prev_win == 0));
        u32 len, cpl = 0, ndesc, wr_len;
        struct fw_ulptx_wr *wr;
        int credits;
        void *pos;

        wr_len = sizeof(*wr);
        /* there can be max 4 cpls, check if we have enough credits */
        len = wr_len + 4 * roundup(CHCR_SET_TCB_FIELD_LEN, 16);
        ndesc = DIV_ROUND_UP(len, 64);

        credits = chcr_txq_avail(&q->q) - ndesc;
        if (unlikely(credits < 0)) {
                chcr_eth_txq_stop(q);
                return NETDEV_TX_BUSY;
        }

        pos = &q->q.desc[q->q.pidx];
        /* make space for WR, we'll fill it later when we know all the cpls
         * being sent out and have complete length.
         */
        wr = pos;
        pos += wr_len;
        /* update tx_max if its a re-transmit or the first wr */
        if (first_wr || tcp_seq != tx_info->prev_seq) {
                pos = chcr_write_cpl_set_tcb_ulp(tx_info, q, tx_info->tid, pos,
                                                 TCB_TX_MAX_W,
                                                 TCB_TX_MAX_V(TCB_TX_MAX_M),
                                                 TCB_TX_MAX_V(tcp_seq), 0);
                cpl++;
        }
        /* reset snd una if it's a re-transmit pkt */
        if (tcp_seq != tx_info->prev_seq) {
                /* reset snd_una */
                pos = chcr_write_cpl_set_tcb_ulp(tx_info, q, tx_info->tid, pos,
                                                 TCB_SND_UNA_RAW_W,
                                                 TCB_SND_UNA_RAW_V
                                                 (TCB_SND_UNA_RAW_M),
                                                 TCB_SND_UNA_RAW_V(0), 0);
                atomic64_inc(&tx_info->adap->chcr_stats.ktls_tx_ooo);
                cpl++;
        }
        /* update ack */
        if (first_wr || tx_info->prev_ack != tcp_ack) {
                pos = chcr_write_cpl_set_tcb_ulp(tx_info, q, tx_info->tid, pos,
                                                 TCB_RCV_NXT_W,
                                                 TCB_RCV_NXT_V(TCB_RCV_NXT_M),
                                                 TCB_RCV_NXT_V(tcp_ack), 0);
                tx_info->prev_ack = tcp_ack;
                cpl++;
        }
        /* update receive window */
        if (first_wr || tx_info->prev_win != tcp_win) {
                pos = chcr_write_cpl_set_tcb_ulp(tx_info, q, tx_info->tid, pos,
                                                 TCB_RCV_WND_W,
                                                 TCB_RCV_WND_V(TCB_RCV_WND_M),
                                                 TCB_RCV_WND_V(tcp_win), 0);
                tx_info->prev_win = tcp_win;
                cpl++;
        }

        if (cpl) {
                /* get the actual length */
                len = wr_len + cpl * roundup(CHCR_SET_TCB_FIELD_LEN, 16);
                /* ULPTX wr */
                wr->op_to_compl = htonl(FW_WR_OP_V(FW_ULPTX_WR));
                wr->cookie = 0;
                /* fill len in wr field */
                wr->flowid_len16 = htonl(FW_WR_LEN16_V(DIV_ROUND_UP(len, 16)));

                ndesc = DIV_ROUND_UP(len, 64);
                chcr_txq_advance(&q->q, ndesc);
                cxgb4_ring_tx_db(tx_info->adap, &q->q, ndesc);
        }
        return 0;
}

/*
 * chcr_ktls_skb_copy
 * @nskb - new skb where the frags to be added.
 * @skb - old skb from which frags will be copied.
 */
static void chcr_ktls_skb_copy(struct sk_buff *skb, struct sk_buff *nskb)
{
        int i;

        for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
                skb_shinfo(nskb)->frags[i] = skb_shinfo(skb)->frags[i];
                __skb_frag_ref(&skb_shinfo(nskb)->frags[i]);
        }

        skb_shinfo(nskb)->nr_frags = skb_shinfo(skb)->nr_frags;
        nskb->len += skb->data_len;
        nskb->data_len = skb->data_len;
        nskb->truesize += skb->data_len;
}

/*
 * chcr_ktls_get_tx_flits
 * returns number of flits to be sent out, it includes key context length, WR
 * size and skb fragments.
 */
static unsigned int
chcr_ktls_get_tx_flits(const struct sk_buff *skb, unsigned int key_ctx_len)
{
        return chcr_sgl_len(skb_shinfo(skb)->nr_frags) +
               DIV_ROUND_UP(key_ctx_len + CHCR_KTLS_WR_SIZE, 8);
}

/*
 * chcr_ktls_check_tcp_options: To check if there is any TCP option availbale
 * other than timestamp.
 * @skb - skb contains partial record..
 * return: 1 / 0
 */
static int
chcr_ktls_check_tcp_options(struct tcphdr *tcp)
{
        int cnt, opt, optlen;
        u_char *cp;

        cp = (u_char *)(tcp + 1);
        cnt = (tcp->doff << 2) - sizeof(struct tcphdr);
        for (; cnt > 0; cnt -= optlen, cp += optlen) {
                opt = cp[0];
                if (opt == TCPOPT_EOL)
                        break;
                if (opt == TCPOPT_NOP) {
                        optlen = 1;
                } else {
                        if (cnt < 2)
                                break;
                        optlen = cp[1];
                        if (optlen < 2 || optlen > cnt)
                                break;
                }
                switch (opt) {
                case TCPOPT_NOP:
                        break;
                default:
                        return 1;
                }
        }
        return 0;
}

/*
 * chcr_ktls_write_tcp_options : TP can't send out all the options, we need to
 * send out separately.
 * @tx_info - driver specific tls info.
 * @skb - skb contains partial record..
 * @q - TX queue.
 * @tx_chan - channel number.
 * return: NETDEV_TX_OK/NETDEV_TX_BUSY.
 */
static int
chcr_ktls_write_tcp_options(struct chcr_ktls_info *tx_info, struct sk_buff *skb,
                            struct sge_eth_txq *q, uint32_t tx_chan)
{
        struct fw_eth_tx_pkt_wr *wr;
        struct cpl_tx_pkt_core *cpl;
        u32 ctrl, iplen, maclen;
        struct ipv6hdr *ip6;
        unsigned int ndesc;
        struct tcphdr *tcp;
        int len16, pktlen;
        struct iphdr *ip;
        int credits;
        u8 buf[150];
        void *pos;

        iplen = skb_network_header_len(skb);
        maclen = skb_mac_header_len(skb);

        /* packet length = eth hdr len + ip hdr len + tcp hdr len
         * (including options).
         */
        pktlen = skb->len - skb->data_len;

        ctrl = sizeof(*cpl) + pktlen;
        len16 = DIV_ROUND_UP(sizeof(*wr) + ctrl, 16);
        /* check how many descriptors needed */
        ndesc = DIV_ROUND_UP(len16, 4);

        credits = chcr_txq_avail(&q->q) - ndesc;
        if (unlikely(credits < 0)) {
                chcr_eth_txq_stop(q);
                return NETDEV_TX_BUSY;
        }

        pos = &q->q.desc[q->q.pidx];
        wr = pos;

        /* Firmware work request header */
        wr->op_immdlen = htonl(FW_WR_OP_V(FW_ETH_TX_PKT_WR) |
                               FW_WR_IMMDLEN_V(ctrl));

        wr->equiq_to_len16 = htonl(FW_WR_LEN16_V(len16));
        wr->r3 = 0;

        cpl = (void *)(wr + 1);

        /* CPL header */
        cpl->ctrl0 = htonl(TXPKT_OPCODE_V(CPL_TX_PKT) | TXPKT_INTF_V(tx_chan) |
                           TXPKT_PF_V(tx_info->adap->pf));
        cpl->pack = 0;
        cpl->len = htons(pktlen);
        /* checksum offload */
        cpl->ctrl1 = 0;

        pos = cpl + 1;

        memcpy(buf, skb->data, pktlen);
        if (tx_info->ip_family == AF_INET) {
                /* we need to correct ip header len */
                ip = (struct iphdr *)(buf + maclen);
                ip->tot_len = htons(pktlen - maclen);
        } else {
                ip6 = (struct ipv6hdr *)(buf + maclen);
                ip6->payload_len = htons(pktlen - maclen - iplen);
        }
        /* now take care of the tcp header, if fin is not set then clear push
         * bit as well, and if fin is set, it will be sent at the last so we
         * need to update the tcp sequence number as per the last packet.
         */
        tcp = (struct tcphdr *)(buf + maclen + iplen);

        if (!tcp->fin)
                tcp->psh = 0;
        else
                tcp->seq = htonl(tx_info->prev_seq);

        chcr_copy_to_txd(buf, &q->q, pos, pktlen);

        chcr_txq_advance(&q->q, ndesc);
        cxgb4_ring_tx_db(tx_info->adap, &q->q, ndesc);
        return 0;
}

/* chcr_ktls_skb_shift - Shifts request length paged data from skb to another.
 * @tgt- buffer into which tail data gets added
 * @skb- buffer from which the paged data comes from
 * @shiftlen- shift up to this many bytes
 */
static int chcr_ktls_skb_shift(struct sk_buff *tgt, struct sk_buff *skb,
                               int shiftlen)
{
        skb_frag_t *fragfrom, *fragto;
        int from, to, todo;

        WARN_ON(shiftlen > skb->data_len);

        todo = shiftlen;
        from = 0;
        to = 0;
        fragfrom = &skb_shinfo(skb)->frags[from];

        while ((todo > 0) && (from < skb_shinfo(skb)->nr_frags)) {
                fragfrom = &skb_shinfo(skb)->frags[from];
                fragto = &skb_shinfo(tgt)->frags[to];

                if (todo >= skb_frag_size(fragfrom)) {
                        *fragto = *fragfrom;
                        todo -= skb_frag_size(fragfrom);
                        from++;
                        to++;

                } else {
                        __skb_frag_ref(fragfrom);
                        skb_frag_page_copy(fragto, fragfrom);
                        skb_frag_off_copy(fragto, fragfrom);
                        skb_frag_size_set(fragto, todo);

                        skb_frag_off_add(fragfrom, todo);
                        skb_frag_size_sub(fragfrom, todo);
                        todo = 0;

                        to++;
                        break;
                }
        }

        /* Ready to "commit" this state change to tgt */
        skb_shinfo(tgt)->nr_frags = to;

        /* Reposition in the original skb */
        to = 0;
        while (from < skb_shinfo(skb)->nr_frags)
                skb_shinfo(skb)->frags[to++] = skb_shinfo(skb)->frags[from++];

        skb_shinfo(skb)->nr_frags = to;

        WARN_ON(todo > 0 && !skb_shinfo(skb)->nr_frags);

        skb->len -= shiftlen;
        skb->data_len -= shiftlen;
        skb->truesize -= shiftlen;
        tgt->len += shiftlen;
        tgt->data_len += shiftlen;
        tgt->truesize += shiftlen;

        return shiftlen;
}

/*
 * chcr_ktls_xmit_wr_complete: This sends out the complete record. If an skb
 * received has partial end part of the record, send out the complete record, so
 * that crypto block will be able to generate TAG/HASH.
 * @skb - segment which has complete or partial end part.
 * @tx_info - driver specific tls info.
 * @q - TX queue.
 * @tcp_seq
 * @tcp_push - tcp push bit.
 * @mss - segment size.
 * return: NETDEV_TX_BUSY/NET_TX_OK.
 */
static int chcr_ktls_xmit_wr_complete(struct sk_buff *skb,
                                      struct chcr_ktls_info *tx_info,
                                      struct sge_eth_txq *q, u32 tcp_seq,
                                      bool tcp_push, u32 mss)
{
        u32 len16, wr_mid = 0, flits = 0, ndesc, cipher_start;
        struct adapter *adap = tx_info->adap;
        int credits, left, last_desc;
        struct tx_sw_desc *sgl_sdesc;
        struct cpl_tx_data *tx_data;
        struct cpl_tx_sec_pdu *cpl;
        struct ulptx_idata *idata;
        struct ulp_txpkt *ulptx;
        struct fw_ulptx_wr *wr;
        void *pos;
        u64 *end;

        /* get the number of flits required */
        flits = chcr_ktls_get_tx_flits(skb, tx_info->key_ctx_len);
        /* number of descriptors */
        ndesc = chcr_flits_to_desc(flits);
        /* check if enough credits available */
        credits = chcr_txq_avail(&q->q) - ndesc;
        if (unlikely(credits < 0)) {
                chcr_eth_txq_stop(q);
                return NETDEV_TX_BUSY;
        }

        if (unlikely(credits < ETHTXQ_STOP_THRES)) {
                /* Credits are below the threshold vaues, stop the queue after
                 * injecting the Work Request for this packet.
                 */
                chcr_eth_txq_stop(q);
                wr_mid |= FW_WR_EQUEQ_F | FW_WR_EQUIQ_F;
        }

        last_desc = q->q.pidx + ndesc - 1;
        if (last_desc >= q->q.size)
                last_desc -= q->q.size;
        sgl_sdesc = &q->q.sdesc[last_desc];

        if (unlikely(cxgb4_map_skb(adap->pdev_dev, skb, sgl_sdesc->addr) < 0)) {
                memset(sgl_sdesc->addr, 0, sizeof(sgl_sdesc->addr));
                q->mapping_err++;
                return NETDEV_TX_BUSY;
        }

        pos = &q->q.desc[q->q.pidx];
        end = (u64 *)pos + flits;
        /* FW_ULPTX_WR */
        wr = pos;
        /* WR will need len16 */
        len16 = DIV_ROUND_UP(flits, 2);
        wr->op_to_compl = htonl(FW_WR_OP_V(FW_ULPTX_WR));
        wr->flowid_len16 = htonl(wr_mid | FW_WR_LEN16_V(len16));
        wr->cookie = 0;
        pos += sizeof(*wr);
        /* ULP_TXPKT */
        ulptx = pos;
        ulptx->cmd_dest = htonl(ULPTX_CMD_V(ULP_TX_PKT) |
                                ULP_TXPKT_CHANNELID_V(tx_info->port_id) |
                                ULP_TXPKT_FID_V(q->q.cntxt_id) |
                                ULP_TXPKT_RO_F);
        ulptx->len = htonl(len16 - 1);
        /* ULPTX_IDATA sub-command */
        idata = (struct ulptx_idata *)(ulptx + 1);
        idata->cmd_more = htonl(ULPTX_CMD_V(ULP_TX_SC_IMM) | ULP_TX_SC_MORE_F);
        /* idata length will include cpl_tx_sec_pdu + key context size +
         * cpl_tx_data header.
         */
        idata->len = htonl(sizeof(*cpl) + tx_info->key_ctx_len +
                           sizeof(*tx_data));
        /* SEC CPL */
        cpl = (struct cpl_tx_sec_pdu *)(idata + 1);
        cpl->op_ivinsrtofst =
                htonl(CPL_TX_SEC_PDU_OPCODE_V(CPL_TX_SEC_PDU) |
                      CPL_TX_SEC_PDU_CPLLEN_V(CHCR_CPL_TX_SEC_PDU_LEN_64BIT) |
                      CPL_TX_SEC_PDU_PLACEHOLDER_V(1) |
                      CPL_TX_SEC_PDU_IVINSRTOFST_V(TLS_HEADER_SIZE + 1));
        cpl->pldlen = htonl(skb->data_len);

        /* encryption should start after tls header size + iv size */
        cipher_start = TLS_HEADER_SIZE + tx_info->iv_size + 1;

        cpl->aadstart_cipherstop_hi =
                htonl(CPL_TX_SEC_PDU_AADSTART_V(1) |
                      CPL_TX_SEC_PDU_AADSTOP_V(TLS_HEADER_SIZE) |
                      CPL_TX_SEC_PDU_CIPHERSTART_V(cipher_start));

        /* authentication will also start after tls header + iv size */
        cpl->cipherstop_lo_authinsert =
        htonl(CPL_TX_SEC_PDU_AUTHSTART_V(cipher_start) |
              CPL_TX_SEC_PDU_AUTHSTOP_V(TLS_CIPHER_AES_GCM_128_TAG_SIZE) |
              CPL_TX_SEC_PDU_AUTHINSERT_V(TLS_CIPHER_AES_GCM_128_TAG_SIZE));

        /* These two flits are actually a CPL_TLS_TX_SCMD_FMT. */
        cpl->seqno_numivs = htonl(tx_info->scmd0_seqno_numivs);
        cpl->ivgen_hdrlen = htonl(tx_info->scmd0_ivgen_hdrlen);
        cpl->scmd1 = cpu_to_be64(tx_info->record_no);

        pos = cpl + 1;
        /* check if space left to fill the keys */
        left = (void *)q->q.stat - pos;
        if (!left) {
                left = (void *)end - (void *)q->q.stat;
                pos = q->q.desc;
                end = pos + left;
        }

        pos = chcr_copy_to_txd(&tx_info->key_ctx, &q->q, pos,
                               tx_info->key_ctx_len);
        left = (void *)q->q.stat - pos;

        if (!left) {
                left = (void *)end - (void *)q->q.stat;
                pos = q->q.desc;
                end = pos + left;
        }
        /* CPL_TX_DATA */
        tx_data = (void *)pos;
        OPCODE_TID(tx_data) = htonl(MK_OPCODE_TID(CPL_TX_DATA, tx_info->tid));
        tx_data->len = htonl(TX_DATA_MSS_V(mss) | TX_LENGTH_V(skb->data_len));

        tx_data->rsvd = htonl(tcp_seq);

        tx_data->flags = htonl(TX_BYPASS_F);
        if (tcp_push)
                tx_data->flags |= htonl(TX_PUSH_F | TX_SHOVE_F);

        /* check left again, it might go beyond queue limit */
        pos = tx_data + 1;
        left = (void *)q->q.stat - pos;

        /* check the position again */
        if (!left) {
                left = (void *)end - (void *)q->q.stat;
                pos = q->q.desc;
                end = pos + left;
        }

        /* send the complete packet except the header */
        cxgb4_write_sgl(skb, &q->q, pos, end, skb->len - skb->data_len,
                        sgl_sdesc->addr);
        sgl_sdesc->skb = skb;

        chcr_txq_advance(&q->q, ndesc);
        cxgb4_ring_tx_db(adap, &q->q, ndesc);
        atomic64_inc(&adap->chcr_stats.ktls_tx_send_records);

        return 0;
}

/*
 * chcr_ktls_xmit_wr_short: This is to send out partial records. If its
 * a middle part of a record, fetch the prior data to make it 16 byte aligned
 * and then only send it out.
 *
 * @skb - skb contains partial record..
 * @tx_info - driver specific tls info.
 * @q - TX queue.
 * @tcp_seq
 * @tcp_push - tcp push bit.
 * @mss - segment size.
 * @tls_rec_offset - offset from start of the tls record.
 * @perior_data - data before the current segment, required to make this record
 *                16 byte aligned.
 * @prior_data_len - prior_data length (less than 16)
 * return: NETDEV_TX_BUSY/NET_TX_OK.
 */
static int chcr_ktls_xmit_wr_short(struct sk_buff *skb,
                                   struct chcr_ktls_info *tx_info,
                                   struct sge_eth_txq *q,
                                   u32 tcp_seq, bool tcp_push, u32 mss,
                                   u32 tls_rec_offset, u8 *prior_data,
                                   u32 prior_data_len)
{
        struct adapter *adap = tx_info->adap;
        u32 len16, wr_mid = 0, cipher_start;
        unsigned int flits = 0, ndesc;
        int credits, left, last_desc;
        struct tx_sw_desc *sgl_sdesc;
        struct cpl_tx_data *tx_data;
        struct cpl_tx_sec_pdu *cpl;
        struct ulptx_idata *idata;
        struct ulp_txpkt *ulptx;
        struct fw_ulptx_wr *wr;
        __be64 iv_record;
        void *pos;
        u64 *end;

        /* get the number of flits required, it's a partial record so 2 flits
         * (AES_BLOCK_SIZE) will be added.
         */
        flits = chcr_ktls_get_tx_flits(skb, tx_info->key_ctx_len) + 2;
        /* get the correct 8 byte IV of this record */
        iv_record = cpu_to_be64(tx_info->iv + tx_info->record_no);
        /* If it's a middle record and not 16 byte aligned to run AES CTR, need
         * to make it 16 byte aligned. So atleadt 2 extra flits of immediate
         * data will be added.
         */
        if (prior_data_len)
                flits += 2;
        /* number of descriptors */
        ndesc = chcr_flits_to_desc(flits);
        /* check if enough credits available */
        credits = chcr_txq_avail(&q->q) - ndesc;
        if (unlikely(credits < 0)) {
                chcr_eth_txq_stop(q);
                return NETDEV_TX_BUSY;
        }

        if (unlikely(credits < ETHTXQ_STOP_THRES)) {
                chcr_eth_txq_stop(q);
                wr_mid |= FW_WR_EQUEQ_F | FW_WR_EQUIQ_F;
        }

        last_desc = q->q.pidx + ndesc - 1;
        if (last_desc >= q->q.size)
                last_desc -= q->q.size;
        sgl_sdesc = &q->q.sdesc[last_desc];

        if (unlikely(cxgb4_map_skb(adap->pdev_dev, skb, sgl_sdesc->addr) < 0)) {
                memset(sgl_sdesc->addr, 0, sizeof(sgl_sdesc->addr));
                q->mapping_err++;
                return NETDEV_TX_BUSY;
        }

        pos = &q->q.desc[q->q.pidx];
        end = (u64 *)pos + flits;
        /* FW_ULPTX_WR */
        wr = pos;
        /* WR will need len16 */
        len16 = DIV_ROUND_UP(flits, 2);
        wr->op_to_compl = htonl(FW_WR_OP_V(FW_ULPTX_WR));
        wr->flowid_len16 = htonl(wr_mid | FW_WR_LEN16_V(len16));
        wr->cookie = 0;
        pos += sizeof(*wr);
        /* ULP_TXPKT */
        ulptx = pos;
        ulptx->cmd_dest = htonl(ULPTX_CMD_V(ULP_TX_PKT) |
                                ULP_TXPKT_CHANNELID_V(tx_info->port_id) |
                                ULP_TXPKT_FID_V(q->q.cntxt_id) |
                                ULP_TXPKT_RO_F);
        ulptx->len = htonl(len16 - 1);
        /* ULPTX_IDATA sub-command */
        idata = (struct ulptx_idata *)(ulptx + 1);
        idata->cmd_more = htonl(ULPTX_CMD_V(ULP_TX_SC_IMM) | ULP_TX_SC_MORE_F);
        /* idata length will include cpl_tx_sec_pdu + key context size +
         * cpl_tx_data header.
         */
        idata->len = htonl(sizeof(*cpl) + tx_info->key_ctx_len +
                           sizeof(*tx_data) + AES_BLOCK_LEN + prior_data_len);
        /* SEC CPL */
        cpl = (struct cpl_tx_sec_pdu *)(idata + 1);
        /* cipher start will have tls header + iv size extra if its a header
         * part of tls record. else only 16 byte IV will be added.
         */
        cipher_start =
                AES_BLOCK_LEN + 1 +
                (!tls_rec_offset ? TLS_HEADER_SIZE + tx_info->iv_size : 0);

        cpl->op_ivinsrtofst =
                htonl(CPL_TX_SEC_PDU_OPCODE_V(CPL_TX_SEC_PDU) |
                      CPL_TX_SEC_PDU_CPLLEN_V(CHCR_CPL_TX_SEC_PDU_LEN_64BIT) |
                      CPL_TX_SEC_PDU_IVINSRTOFST_V(1));
        cpl->pldlen = htonl(skb->data_len + AES_BLOCK_LEN + prior_data_len);
        cpl->aadstart_cipherstop_hi =
                htonl(CPL_TX_SEC_PDU_CIPHERSTART_V(cipher_start));
        cpl->cipherstop_lo_authinsert = 0;
        /* These two flits are actually a CPL_TLS_TX_SCMD_FMT. */
        cpl->seqno_numivs = htonl(tx_info->scmd0_short_seqno_numivs);
        cpl->ivgen_hdrlen = htonl(tx_info->scmd0_short_ivgen_hdrlen);
        cpl->scmd1 = 0;

        pos = cpl + 1;
        /* check if space left to fill the keys */
        left = (void *)q->q.stat - pos;
        if (!left) {
                left = (void *)end - (void *)q->q.stat;
                pos = q->q.desc;
                end = pos + left;
        }

        pos = chcr_copy_to_txd(&tx_info->key_ctx, &q->q, pos,
                               tx_info->key_ctx_len);
        left = (void *)q->q.stat - pos;

        if (!left) {
                left = (void *)end - (void *)q->q.stat;
                pos = q->q.desc;
                end = pos + left;
        }
        /* CPL_TX_DATA */
        tx_data = (void *)pos;
        OPCODE_TID(tx_data) = htonl(MK_OPCODE_TID(CPL_TX_DATA, tx_info->tid));
        tx_data->len = htonl(TX_DATA_MSS_V(mss) |
                        TX_LENGTH_V(skb->data_len + prior_data_len));
        tx_data->rsvd = htonl(tcp_seq);
        tx_data->flags = htonl(TX_BYPASS_F);
        if (tcp_push)
                tx_data->flags |= htonl(TX_PUSH_F | TX_SHOVE_F);

        /* check left again, it might go beyond queue limit */
        pos = tx_data + 1;
        left = (void *)q->q.stat - pos;

        /* check the position again */
        if (!left) {
                left = (void *)end - (void *)q->q.stat;
                pos = q->q.desc;
                end = pos + left;
        }
        /* copy the 16 byte IV for AES-CTR, which includes 4 bytes of salt, 8
         * bytes of actual IV and 4 bytes of 16 byte-sequence.
         */
        memcpy(pos, tx_info->key_ctx.salt, tx_info->salt_size);
        memcpy(pos + tx_info->salt_size, &iv_record, tx_info->iv_size);
        *(__be32 *)(pos + tx_info->salt_size + tx_info->iv_size) =
                htonl(2 + (tls_rec_offset ? ((tls_rec_offset -
                (TLS_HEADER_SIZE + tx_info->iv_size)) / AES_BLOCK_LEN) : 0));

        pos += 16;
        /* Prior_data_len will always be less than 16 bytes, fill the
         * prio_data_len after AES_CTRL_BLOCK and clear the remaining length
         * to 0.
         */
        if (prior_data_len)
                pos = chcr_copy_to_txd(prior_data, &q->q, pos, 16);
        /* send the complete packet except the header */
        cxgb4_write_sgl(skb, &q->q, pos, end, skb->len - skb->data_len,
                        sgl_sdesc->addr);
        sgl_sdesc->skb = skb;

        chcr_txq_advance(&q->q, ndesc);
        cxgb4_ring_tx_db(adap, &q->q, ndesc);

        return 0;
}

/*
 * chcr_ktls_tx_plaintxt: This handler will take care of the records which has
 * only plain text (only tls header and iv)
 * @tx_info - driver specific tls info.
 * @skb - skb contains partial record..
 * @tcp_seq
 * @mss - segment size.
 * @tcp_push - tcp push bit.
 * @q - TX queue.
 * @port_id : port number
 * @perior_data - data before the current segment, required to make this record
 *               16 byte aligned.
 * @prior_data_len - prior_data length (less than 16)
 * return: NETDEV_TX_BUSY/NET_TX_OK.
 */
static int chcr_ktls_tx_plaintxt(struct chcr_ktls_info *tx_info,
                                 struct sk_buff *skb, u32 tcp_seq, u32 mss,
                                 bool tcp_push, struct sge_eth_txq *q,
                                 u32 port_id, u8 *prior_data,
                                 u32 prior_data_len)
{
        int credits, left, len16, last_desc;
        unsigned int flits = 0, ndesc;
        struct tx_sw_desc *sgl_sdesc;
        struct cpl_tx_data *tx_data;
        struct ulptx_idata *idata;
        struct ulp_txpkt *ulptx;
        struct fw_ulptx_wr *wr;
        u32 wr_mid = 0;
        void *pos;
        u64 *end;

        flits = DIV_ROUND_UP(CHCR_PLAIN_TX_DATA_LEN, 8);
        flits += chcr_sgl_len(skb_shinfo(skb)->nr_frags);
        if (prior_data_len)
                flits += 2;
        /* WR will need len16 */
        len16 = DIV_ROUND_UP(flits, 2);
        /* check how many descriptors needed */
        ndesc = DIV_ROUND_UP(flits, 8);

        credits = chcr_txq_avail(&q->q) - ndesc;
        if (unlikely(credits < 0)) {
                chcr_eth_txq_stop(q);
                return NETDEV_TX_BUSY;
        }

        if (unlikely(credits < ETHTXQ_STOP_THRES)) {
                chcr_eth_txq_stop(q);
                wr_mid |= FW_WR_EQUEQ_F | FW_WR_EQUIQ_F;
        }

        last_desc = q->q.pidx + ndesc - 1;
        if (last_desc >= q->q.size)
                last_desc -= q->q.size;
        sgl_sdesc = &q->q.sdesc[last_desc];

        if (unlikely(cxgb4_map_skb(tx_info->adap->pdev_dev, skb,
                                   sgl_sdesc->addr) < 0)) {
                memset(sgl_sdesc->addr, 0, sizeof(sgl_sdesc->addr));
                q->mapping_err++;
                return NETDEV_TX_BUSY;
        }

        pos = &q->q.desc[q->q.pidx];
        end = (u64 *)pos + flits;
        /* FW_ULPTX_WR */
        wr = pos;
        wr->op_to_compl = htonl(FW_WR_OP_V(FW_ULPTX_WR));
        wr->flowid_len16 = htonl(wr_mid | FW_WR_LEN16_V(len16));
        wr->cookie = 0;
        pos += sizeof(*wr);
        /* ULP_TXPKT */
        ulptx = (struct ulp_txpkt *)(wr + 1);
        ulptx->cmd_dest = htonl(ULPTX_CMD_V(ULP_TX_PKT) |
                        ULP_TXPKT_DATAMODIFY_V(0) |
                        ULP_TXPKT_CHANNELID_V(tx_info->port_id) |
                        ULP_TXPKT_DEST_V(0) |
                        ULP_TXPKT_FID_V(q->q.cntxt_id) | ULP_TXPKT_RO_V(1));
        ulptx->len = htonl(len16 - 1);
        /* ULPTX_IDATA sub-command */
        idata = (struct ulptx_idata *)(ulptx + 1);
        idata->cmd_more = htonl(ULPTX_CMD_V(ULP_TX_SC_IMM) | ULP_TX_SC_MORE_F);
        idata->len = htonl(sizeof(*tx_data) + prior_data_len);
        /* CPL_TX_DATA */
        tx_data = (struct cpl_tx_data *)(idata + 1);
        OPCODE_TID(tx_data) = htonl(MK_OPCODE_TID(CPL_TX_DATA, tx_info->tid));
        tx_data->len = htonl(TX_DATA_MSS_V(mss) |
                        TX_LENGTH_V(skb->data_len + prior_data_len));
        /* set tcp seq number */
        tx_data->rsvd = htonl(tcp_seq);
        tx_data->flags = htonl(TX_BYPASS_F);
        if (tcp_push)
                tx_data->flags |= htonl(TX_PUSH_F | TX_SHOVE_F);

        pos = tx_data + 1;
        /* apart from prior_data_len, we should set remaining part of 16 bytes
         * to be zero.
         */
        if (prior_data_len)
                pos = chcr_copy_to_txd(prior_data, &q->q, pos, 16);

        /* check left again, it might go beyond queue limit */
        left = (void *)q->q.stat - pos;

        /* check the position again */
        if (!left) {
                left = (void *)end - (void *)q->q.stat;
                pos = q->q.desc;
                end = pos + left;
        }
        /* send the complete packet including the header */
        cxgb4_write_sgl(skb, &q->q, pos, end, skb->len - skb->data_len,
                        sgl_sdesc->addr);
        sgl_sdesc->skb = skb;

        chcr_txq_advance(&q->q, ndesc);
        cxgb4_ring_tx_db(tx_info->adap, &q->q, ndesc);
        return 0;
}

/*
 * chcr_ktls_copy_record_in_skb
 * @nskb - new skb where the frags to be added.
 * @record - specific record which has complete 16k record in frags.
 */
static void chcr_ktls_copy_record_in_skb(struct sk_buff *nskb,
                                         struct tls_record_info *record)
{
        int i = 0;

        for (i = 0; i < record->num_frags; i++) {
                skb_shinfo(nskb)->frags[i] = record->frags[i];
                /* increase the frag ref count */
                __skb_frag_ref(&skb_shinfo(nskb)->frags[i]);
        }

        skb_shinfo(nskb)->nr_frags = record->num_frags;
        nskb->data_len = record->len;
        nskb->len += record->len;
        nskb->truesize += record->len;
}

/*
 * chcr_ktls_update_snd_una:  Reset the SEND_UNA. It will be done to avoid
 * sending the same segment again. It will discard the segment which is before
 * the current tx max.
 * @tx_info - driver specific tls info.
 * @q - TX queue.
 * return: NET_TX_OK/NET_XMIT_DROP.
 */
static int chcr_ktls_update_snd_una(struct chcr_ktls_info *tx_info,
                                    struct sge_eth_txq *q)
{
        struct fw_ulptx_wr *wr;
        unsigned int ndesc;
        int credits;
        void *pos;
        u32 len;

        len = sizeof(*wr) + roundup(CHCR_SET_TCB_FIELD_LEN, 16);
        ndesc = DIV_ROUND_UP(len, 64);

        credits = chcr_txq_avail(&q->q) - ndesc;
        if (unlikely(credits < 0)) {
                chcr_eth_txq_stop(q);
                return NETDEV_TX_BUSY;
        }

        pos = &q->q.desc[q->q.pidx];

        wr = pos;
        /* ULPTX wr */
        wr->op_to_compl = htonl(FW_WR_OP_V(FW_ULPTX_WR));
        wr->cookie = 0;
        /* fill len in wr field */
        wr->flowid_len16 = htonl(FW_WR_LEN16_V(DIV_ROUND_UP(len, 16)));

        pos += sizeof(*wr);

        pos = chcr_write_cpl_set_tcb_ulp(tx_info, q, tx_info->tid, pos,
                                         TCB_SND_UNA_RAW_W,
                                         TCB_SND_UNA_RAW_V(TCB_SND_UNA_RAW_M),
                                         TCB_SND_UNA_RAW_V(0), 0);

        chcr_txq_advance(&q->q, ndesc);
        cxgb4_ring_tx_db(tx_info->adap, &q->q, ndesc);

        return 0;
}

/*
 * chcr_end_part_handler: This handler will handle the record which
 * is complete or if record's end part is received. T6 adapter has a issue that
 * it can't send out TAG with partial record so if its an end part then we have
 * to send TAG as well and for which we need to fetch the complete record and
 * send it to crypto module.
 * @tx_info - driver specific tls info.
 * @skb - skb contains partial record.
 * @record - complete record of 16K size.
 * @tcp_seq
 * @mss - segment size in which TP needs to chop a packet.
 * @tcp_push_no_fin - tcp push if fin is not set.
 * @q - TX queue.
 * @tls_end_offset - offset from end of the record.
 * @last wr : check if this is the last part of the skb going out.
 * return: NETDEV_TX_OK/NETDEV_TX_BUSY.
 */
static int chcr_end_part_handler(struct chcr_ktls_info *tx_info,
                                 struct sk_buff *skb,
                                 struct tls_record_info *record,
                                 u32 tcp_seq, int mss, bool tcp_push_no_fin,
                                 struct sge_eth_txq *q,
                                 u32 tls_end_offset, bool last_wr)
{
        struct sk_buff *nskb = NULL;
        /* check if it is a complete record */
        if (tls_end_offset == record->len) {
                nskb = skb;
                atomic64_inc(&tx_info->adap->chcr_stats.ktls_tx_complete_pkts);
        } else {
                dev_kfree_skb_any(skb);

                nskb = alloc_skb(0, GFP_KERNEL);
                if (!nskb)
                        return NETDEV_TX_BUSY;
                /* copy complete record in skb */
                chcr_ktls_copy_record_in_skb(nskb, record);
                /* packet is being sent from the beginning, update the tcp_seq
                 * accordingly.
                 */
                tcp_seq = tls_record_start_seq(record);
                /* reset snd una, so the middle record won't send the already
                 * sent part.
                 */
                if (chcr_ktls_update_snd_una(tx_info, q))
                        goto out;
                atomic64_inc(&tx_info->adap->chcr_stats.ktls_tx_end_pkts);
        }

        if (chcr_ktls_xmit_wr_complete(nskb, tx_info, q, tcp_seq,
                                       (last_wr && tcp_push_no_fin),
                                       mss)) {
                goto out;
        }
        return 0;
out:
        dev_kfree_skb_any(nskb);
        return NETDEV_TX_BUSY;
}

/*
 * chcr_short_record_handler: This handler will take care of the records which
 * doesn't have end part (1st part or the middle part(/s) of a record). In such
 * cases, AES CTR will be used in place of AES GCM to send out partial packet.
 * This partial record might be the first part of the record, or the middle
 * part. In case of middle record we should fetch the prior data to make it 16
 * byte aligned. If it has a partial tls header or iv then get to the start of
 * tls header. And if it has partial TAG, then remove the complete TAG and send
 * only the payload.
 * There is one more possibility that it gets a partial header, send that
 * portion as a plaintext.
 * @tx_info - driver specific tls info.
 * @skb - skb contains partial record..
 * @record - complete record of 16K size.
 * @tcp_seq
 * @mss - segment size in which TP needs to chop a packet.
 * @tcp_push_no_fin - tcp push if fin is not set.
 * @q - TX queue.
 * @tls_end_offset - offset from end of the record.
 * return: NETDEV_TX_OK/NETDEV_TX_BUSY.
 */
static int chcr_short_record_handler(struct chcr_ktls_info *tx_info,
                                     struct sk_buff *skb,
                                     struct tls_record_info *record,
                                     u32 tcp_seq, int mss, bool tcp_push_no_fin,
                                     struct sge_eth_txq *q, u32 tls_end_offset)
{
        u32 tls_rec_offset = tcp_seq - tls_record_start_seq(record);
        u8 prior_data[16] = {0};
        u32 prior_data_len = 0;
        u32 data_len;

        /* check if the skb is ending in middle of tag/HASH, its a big
         * trouble, send the packet before the HASH.
         */
        int remaining_record = tls_end_offset - skb->data_len;

        if (remaining_record > 0 &&
            remaining_record < TLS_CIPHER_AES_GCM_128_TAG_SIZE) {
                int trimmed_len = skb->data_len -
                        (TLS_CIPHER_AES_GCM_128_TAG_SIZE - remaining_record);
                struct sk_buff *tmp_skb = NULL;
                /* don't process the pkt if it is only a partial tag */
                if (skb->data_len < TLS_CIPHER_AES_GCM_128_TAG_SIZE)
                        goto out;

                WARN_ON(trimmed_len > skb->data_len);

                /* shift to those many bytes */
                tmp_skb = alloc_skb(0, GFP_KERNEL);
                if (unlikely(!tmp_skb))
                        goto out;

                chcr_ktls_skb_shift(tmp_skb, skb, trimmed_len);
                /* free the last trimmed portion */
                dev_kfree_skb_any(skb);
                skb = tmp_skb;
                atomic64_inc(&tx_info->adap->chcr_stats.ktls_tx_trimmed_pkts);
        }
        data_len = skb->data_len;
        /* check if the middle record's start point is 16 byte aligned. CTR
         * needs 16 byte aligned start point to start encryption.
         */
        if (tls_rec_offset) {
                /* there is an offset from start, means its a middle record */
                int remaining = 0;

                if (tls_rec_offset < (TLS_HEADER_SIZE + tx_info->iv_size)) {
                        prior_data_len = tls_rec_offset;
                        tls_rec_offset = 0;
                        remaining = 0;
                } else {
                        prior_data_len =
                                (tls_rec_offset -
                                (TLS_HEADER_SIZE + tx_info->iv_size))
                                % AES_BLOCK_LEN;
                        remaining = tls_rec_offset - prior_data_len;
                }

                /* if prior_data_len is not zero, means we need to fetch prior
                 * data to make this record 16 byte aligned, or we need to reach
                 * to start offset.
                 */
                if (prior_data_len) {
                        int i = 0;
                        u8 *data = NULL;
                        skb_frag_t *f;
                        u8 *vaddr;
                        int frag_size = 0, frag_delta = 0;

                        while (remaining > 0) {
                                frag_size = skb_frag_size(&record->frags[i]);
                                if (remaining < frag_size)
                                        break;

                                remaining -= frag_size;
                                i++;
                        }
                        f = &record->frags[i];
                        vaddr = kmap_atomic(skb_frag_page(f));

                        data = vaddr + skb_frag_off(f)  + remaining;
                        frag_delta = skb_frag_size(f) - remaining;

                        if (frag_delta >= prior_data_len) {
                                memcpy(prior_data, data, prior_data_len);
                                kunmap_atomic(vaddr);
                        } else {
                                memcpy(prior_data, data, frag_delta);
                                kunmap_atomic(vaddr);
                                /* get the next page */
                                f = &record->frags[i + 1];
                                vaddr = kmap_atomic(skb_frag_page(f));
                                data = vaddr + skb_frag_off(f);
                                memcpy(prior_data + frag_delta,
                                       data, (prior_data_len - frag_delta));
                                kunmap_atomic(vaddr);
                        }
                        /* reset tcp_seq as per the prior_data_required len */
                        tcp_seq -= prior_data_len;
                        /* include prio_data_len for  further calculation.
                         */
                        data_len += prior_data_len;
                }
                /* reset snd una, so the middle record won't send the already
                 * sent part.
                 */
                if (chcr_ktls_update_snd_una(tx_info, q))
                        goto out;
                atomic64_inc(&tx_info->adap->chcr_stats.ktls_tx_middle_pkts);
        } else {
                /* Else means, its a partial first part of the record. Check if
                 * its only the header, don't need to send for encryption then.
                 */
                if (data_len <= TLS_HEADER_SIZE + tx_info->iv_size) {
                        if (chcr_ktls_tx_plaintxt(tx_info, skb, tcp_seq, mss,
                                                  tcp_push_no_fin, q,
                                                  tx_info->port_id,
                                                  prior_data,
                                                  prior_data_len)) {
                                goto out;
                        }
                        return 0;
                }
                atomic64_inc(&tx_info->adap->chcr_stats.ktls_tx_start_pkts);
        }

        if (chcr_ktls_xmit_wr_short(skb, tx_info, q, tcp_seq, tcp_push_no_fin,
                                    mss, tls_rec_offset, prior_data,
                                    prior_data_len)) {
                goto out;
        }

        return 0;
out:
        dev_kfree_skb_any(skb);
        return NETDEV_TX_BUSY;
}

/* nic tls TX handler */
int chcr_ktls_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct chcr_ktls_ofld_ctx_tx *tx_ctx;
        struct tcphdr *th = tcp_hdr(skb);
        int data_len, qidx, ret = 0, mss;
        struct tls_record_info *record;
        struct chcr_stats_debug *stats;
        struct chcr_ktls_info *tx_info;
        u32 tls_end_offset, tcp_seq;
        struct tls_context *tls_ctx;
        struct sk_buff *local_skb;
        int new_connection_state;
        struct sge_eth_txq *q;
        struct adapter *adap;
        unsigned long flags;

        tcp_seq = ntohl(th->seq);

        mss = skb_is_gso(skb) ? skb_shinfo(skb)->gso_size : skb->data_len;

        /* check if we haven't set it for ktls offload */
        if (!skb->sk || !tls_is_sk_tx_device_offloaded(skb->sk))
                goto out;

        tls_ctx = tls_get_ctx(skb->sk);
        if (unlikely(tls_ctx->netdev != dev))
                goto out;

        tx_ctx = chcr_get_ktls_tx_context(tls_ctx);
        tx_info = tx_ctx->chcr_info;

        if (unlikely(!tx_info))
                goto out;

        /* check the connection state, we don't need to pass new connection
         * state, state machine will check and update the new state if it is
         * stuck due to responses not received from HW.
         * Start the tx handling only if state is KTLS_CONN_TX_READY.
         */
        new_connection_state = chcr_ktls_update_connection_state(tx_info, 0);
        if (new_connection_state != KTLS_CONN_TX_READY)
                goto out;

        /* don't touch the original skb, make a new skb to extract each records
         * and send them separately.
         */
        local_skb = alloc_skb(0, GFP_KERNEL);

        if (unlikely(!local_skb))
                return NETDEV_TX_BUSY;

        adap = tx_info->adap;
        stats = &adap->chcr_stats;

        qidx = skb->queue_mapping;
        q = &adap->sge.ethtxq[qidx + tx_info->first_qset];
        cxgb4_reclaim_completed_tx(adap, &q->q, true);
        /* if tcp options are set but finish is not send the options first */
        if (!th->fin && chcr_ktls_check_tcp_options(th)) {
                ret = chcr_ktls_write_tcp_options(tx_info, skb, q,
                                                  tx_info->tx_chan);
                if (ret)
                        return NETDEV_TX_BUSY;
        }
        /* update tcb */
        ret = chcr_ktls_xmit_tcb_cpls(tx_info, q, ntohl(th->seq),
                                      ntohl(th->ack_seq),
                                      ntohs(th->window));
        if (ret) {
                dev_kfree_skb_any(local_skb);
                return NETDEV_TX_BUSY;
        }

        /* copy skb contents into local skb */
        chcr_ktls_skb_copy(skb, local_skb);

        /* go through the skb and send only one record at a time. */
        data_len = skb->data_len;
        /* TCP segments can be in received either complete or partial.
         * chcr_end_part_handler will handle cases if complete record or end
         * part of the record is received. Incase of partial end part of record,
         * we will send the complete record again.
         */

        do {
                int i;

                cxgb4_reclaim_completed_tx(adap, &q->q, true);
                /* lock taken */
                spin_lock_irqsave(&tx_ctx->base.lock, flags);
                /* fetch the tls record */
                record = tls_get_record(&tx_ctx->base, tcp_seq,
                                        &tx_info->record_no);
                /* By the time packet reached to us, ACK is received, and record
                 * won't be found in that case, handle it gracefully.
                 */
                if (unlikely(!record)) {
                        spin_unlock_irqrestore(&tx_ctx->base.lock, flags);
                        atomic64_inc(&stats->ktls_tx_drop_no_sync_data);
                        goto out;
                }

                if (unlikely(tls_record_is_start_marker(record))) {
                        spin_unlock_irqrestore(&tx_ctx->base.lock, flags);
                        atomic64_inc(&stats->ktls_tx_skip_no_sync_data);
                        goto out;
                }

                /* increase page reference count of the record, so that there
                 * won't be any chance of page free in middle if in case stack
                 * receives ACK and try to delete the record.
                 */
                for (i = 0; i < record->num_frags; i++)
                        __skb_frag_ref(&record->frags[i]);
                /* lock cleared */
                spin_unlock_irqrestore(&tx_ctx->base.lock, flags);

                tls_end_offset = record->end_seq - tcp_seq;

                pr_debug("seq 0x%x, end_seq 0x%x prev_seq 0x%x, datalen 0x%x\n",
                         tcp_seq, record->end_seq, tx_info->prev_seq, data_len);
                /* if a tls record is finishing in this SKB */
                if (tls_end_offset <= data_len) {
                        struct sk_buff *nskb = NULL;

                        if (tls_end_offset < data_len) {
                                nskb = alloc_skb(0, GFP_KERNEL);
                                if (unlikely(!nskb)) {
                                        ret = -ENOMEM;
                                        goto clear_ref;
                                }

                                chcr_ktls_skb_shift(nskb, local_skb,
                                                    tls_end_offset);
                        } else {
                                /* its the only record in this skb, directly
                                 * point it.
                                 */
                                nskb = local_skb;
                        }
                        ret = chcr_end_part_handler(tx_info, nskb, record,
                                                    tcp_seq, mss,
                                                    (!th->fin && th->psh), q,
                                                    tls_end_offset,
                                                    (nskb == local_skb));

                        if (ret && nskb != local_skb)
                                dev_kfree_skb_any(local_skb);

                        data_len -= tls_end_offset;
                        /* tcp_seq increment is required to handle next record.
                         */
                        tcp_seq += tls_end_offset;
                } else {
                        ret = chcr_short_record_handler(tx_info, local_skb,
                                                        record, tcp_seq, mss,
                                                        (!th->fin && th->psh),
                                                        q, tls_end_offset);
                        data_len = 0;
                }
clear_ref:
                /* clear the frag ref count which increased locally before */
                for (i = 0; i < record->num_frags; i++) {
                        /* clear the frag ref count */
                        __skb_frag_unref(&record->frags[i]);
                }
                /* if any failure, come out from the loop. */
                if (ret)
                        goto out;
                /* length should never be less than 0 */
                WARN_ON(data_len < 0);

        } while (data_len > 0);

        tx_info->prev_seq = ntohl(th->seq) + skb->data_len;

        atomic64_inc(&stats->ktls_tx_encrypted_packets);
        atomic64_add(skb->data_len, &stats->ktls_tx_encrypted_bytes);

        /* tcp finish is set, send a separate tcp msg including all the options
         * as well.
         */
        if (th->fin)
                chcr_ktls_write_tcp_options(tx_info, skb, q, tx_info->tx_chan);

out:
        dev_kfree_skb_any(skb);
        return NETDEV_TX_OK;
}
#endif /* CONFIG_CHELSIO_TLS_DEVICE */