Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2789 insertions, 0 deletions

diff --git a/drivers/scsi/cxgbi/libcxgbi.c b/drivers/scsi/cxgbi/libcxgbi.c
new file mode 100644
index 000000000..01f5ebee3
--- /dev/null
+++ b/drivers/scsi/cxgbi/libcxgbi.c
@@ -0,0 +1,2789 @@
+/*
+ * libcxgbi.c: Chelsio common library for T3/T4 iSCSI driver.
+ *
+ * Copyright (c) 2010-2015 Chelsio Communications, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation.
+ *
+ * Written by: Karen Xie (kxie@chelsio.com)
+ * Written by: Rakesh Ranjan (rranjan@chelsio.com)
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ":%s: " fmt, __func__
+
+#include <linux/skbuff.h>
+#include <linux/crypto.h>
+#include <linux/scatterlist.h>
+#include <linux/pci.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+#include <linux/if_vlan.h>
+#include <linux/inet.h>
+#include <net/dst.h>
+#include <net/route.h>
+#include <net/ipv6.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+
+#include <linux/inetdevice.h>	/* ip_dev_find */
+#include <linux/module.h>
+#include <net/tcp.h>
+
+static unsigned int dbg_level;
+
+#include "libcxgbi.h"
+
+#define DRV_MODULE_NAME		"libcxgbi"
+#define DRV_MODULE_DESC		"Chelsio iSCSI driver library"
+#define DRV_MODULE_VERSION	"0.9.1-ko"
+#define DRV_MODULE_RELDATE	"Apr. 2015"
+
+static char version[] =
+	DRV_MODULE_DESC " " DRV_MODULE_NAME
+	" v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
+
+MODULE_AUTHOR("Chelsio Communications, Inc.");
+MODULE_DESCRIPTION(DRV_MODULE_DESC);
+MODULE_VERSION(DRV_MODULE_VERSION);
+MODULE_LICENSE("GPL");
+
+module_param(dbg_level, uint, 0644);
+MODULE_PARM_DESC(dbg_level, "libiscsi debug level (default=0)");
+
+
+/*
+ * cxgbi device management
+ * maintains a list of the cxgbi devices
+ */
+static LIST_HEAD(cdev_list);
+static DEFINE_MUTEX(cdev_mutex);
+
+static LIST_HEAD(cdev_rcu_list);
+static DEFINE_SPINLOCK(cdev_rcu_lock);
+
+static inline void cxgbi_decode_sw_tag(u32 sw_tag, int *idx, int *age)
+{
+	if (age)
+		*age = sw_tag & 0x7FFF;
+	if (idx)
+		*idx = (sw_tag >> 16) & 0x7FFF;
+}
+
+int cxgbi_device_portmap_create(struct cxgbi_device *cdev, unsigned int base,
+				unsigned int max_conn)
+{
+	struct cxgbi_ports_map *pmap = &cdev->pmap;
+
+	pmap->port_csk = cxgbi_alloc_big_mem(max_conn *
+					     sizeof(struct cxgbi_sock *),
+					     GFP_KERNEL);
+	if (!pmap->port_csk) {
+		pr_warn("cdev 0x%p, portmap OOM %u.\n", cdev, max_conn);
+		return -ENOMEM;
+	}
+
+	pmap->max_connect = max_conn;
+	pmap->sport_base = base;
+	spin_lock_init(&pmap->lock);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cxgbi_device_portmap_create);
+
+void cxgbi_device_portmap_cleanup(struct cxgbi_device *cdev)
+{
+	struct cxgbi_ports_map *pmap = &cdev->pmap;
+	struct cxgbi_sock *csk;
+	int i;
+
+	for (i = 0; i < pmap->max_connect; i++) {
+		if (pmap->port_csk[i]) {
+			csk = pmap->port_csk[i];
+			pmap->port_csk[i] = NULL;
+			log_debug(1 << CXGBI_DBG_SOCK,
+				"csk 0x%p, cdev 0x%p, offload down.\n",
+				csk, cdev);
+			spin_lock_bh(&csk->lock);
+			cxgbi_sock_set_flag(csk, CTPF_OFFLOAD_DOWN);
+			cxgbi_sock_closed(csk);
+			spin_unlock_bh(&csk->lock);
+			cxgbi_sock_put(csk);
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(cxgbi_device_portmap_cleanup);
+
+static inline void cxgbi_device_destroy(struct cxgbi_device *cdev)
+{
+	log_debug(1 << CXGBI_DBG_DEV,
+		"cdev 0x%p, p# %u.\n", cdev, cdev->nports);
+	cxgbi_hbas_remove(cdev);
+	cxgbi_device_portmap_cleanup(cdev);
+	if (cdev->cdev2ppm)
+		cxgbi_ppm_release(cdev->cdev2ppm(cdev));
+	if (cdev->pmap.max_connect)
+		cxgbi_free_big_mem(cdev->pmap.port_csk);
+	kfree(cdev);
+}
+
+struct cxgbi_device *cxgbi_device_register(unsigned int extra,
+					   unsigned int nports)
+{
+	struct cxgbi_device *cdev;
+
+	cdev = kzalloc(sizeof(*cdev) + extra + nports *
+			(sizeof(struct cxgbi_hba *) +
+			 sizeof(struct net_device *)),
+			GFP_KERNEL);
+	if (!cdev) {
+		pr_warn("nport %d, OOM.\n", nports);
+		return NULL;
+	}
+	cdev->ports = (struct net_device **)(cdev + 1);
+	cdev->hbas = (struct cxgbi_hba **)(((char*)cdev->ports) + nports *
+						sizeof(struct net_device *));
+	if (extra)
+		cdev->dd_data = ((char *)cdev->hbas) +
+				nports * sizeof(struct cxgbi_hba *);
+	spin_lock_init(&cdev->pmap.lock);
+
+	mutex_lock(&cdev_mutex);
+	list_add_tail(&cdev->list_head, &cdev_list);
+	mutex_unlock(&cdev_mutex);
+
+	spin_lock(&cdev_rcu_lock);
+	list_add_tail_rcu(&cdev->rcu_node, &cdev_rcu_list);
+	spin_unlock(&cdev_rcu_lock);
+
+	log_debug(1 << CXGBI_DBG_DEV,
+		"cdev 0x%p, p# %u.\n", cdev, nports);
+	return cdev;
+}
+EXPORT_SYMBOL_GPL(cxgbi_device_register);
+
+void cxgbi_device_unregister(struct cxgbi_device *cdev)
+{
+	log_debug(1 << CXGBI_DBG_DEV,
+		"cdev 0x%p, p# %u,%s.\n",
+		cdev, cdev->nports, cdev->nports ? cdev->ports[0]->name : "");
+
+	mutex_lock(&cdev_mutex);
+	list_del(&cdev->list_head);
+	mutex_unlock(&cdev_mutex);
+
+	spin_lock(&cdev_rcu_lock);
+	list_del_rcu(&cdev->rcu_node);
+	spin_unlock(&cdev_rcu_lock);
+	synchronize_rcu();
+
+	cxgbi_device_destroy(cdev);
+}
+EXPORT_SYMBOL_GPL(cxgbi_device_unregister);
+
+void cxgbi_device_unregister_all(unsigned int flag)
+{
+	struct cxgbi_device *cdev, *tmp;
+
+	mutex_lock(&cdev_mutex);
+	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
+		if ((cdev->flags & flag) == flag) {
+			mutex_unlock(&cdev_mutex);
+			cxgbi_device_unregister(cdev);
+			mutex_lock(&cdev_mutex);
+		}
+	}
+	mutex_unlock(&cdev_mutex);
+}
+EXPORT_SYMBOL_GPL(cxgbi_device_unregister_all);
+
+struct cxgbi_device *cxgbi_device_find_by_lldev(void *lldev)
+{
+	struct cxgbi_device *cdev, *tmp;
+
+	mutex_lock(&cdev_mutex);
+	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
+		if (cdev->lldev == lldev) {
+			mutex_unlock(&cdev_mutex);
+			return cdev;
+		}
+	}
+	mutex_unlock(&cdev_mutex);
+
+	log_debug(1 << CXGBI_DBG_DEV,
+		"lldev 0x%p, NO match found.\n", lldev);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(cxgbi_device_find_by_lldev);
+
+struct cxgbi_device *cxgbi_device_find_by_netdev(struct net_device *ndev,
+						 int *port)
+{
+	struct net_device *vdev = NULL;
+	struct cxgbi_device *cdev, *tmp;
+	int i;
+
+	if (is_vlan_dev(ndev)) {
+		vdev = ndev;
+		ndev = vlan_dev_real_dev(ndev);
+		log_debug(1 << CXGBI_DBG_DEV,
+			"vlan dev %s -> %s.\n", vdev->name, ndev->name);
+	}
+
+	mutex_lock(&cdev_mutex);
+	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
+		for (i = 0; i < cdev->nports; i++) {
+			if (ndev == cdev->ports[i]) {
+				cdev->hbas[i]->vdev = vdev;
+				mutex_unlock(&cdev_mutex);
+				if (port)
+					*port = i;
+				return cdev;
+			}
+		}
+	}
+	mutex_unlock(&cdev_mutex);
+	log_debug(1 << CXGBI_DBG_DEV,
+		"ndev 0x%p, %s, NO match found.\n", ndev, ndev->name);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(cxgbi_device_find_by_netdev);
+
+struct cxgbi_device *cxgbi_device_find_by_netdev_rcu(struct net_device *ndev,
+						     int *port)
+{
+	struct net_device *vdev = NULL;
+	struct cxgbi_device *cdev;
+	int i;
+
+	if (is_vlan_dev(ndev)) {
+		vdev = ndev;
+		ndev = vlan_dev_real_dev(ndev);
+		pr_info("vlan dev %s -> %s.\n", vdev->name, ndev->name);
+	}
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(cdev, &cdev_rcu_list, rcu_node) {
+		for (i = 0; i < cdev->nports; i++) {
+			if (ndev == cdev->ports[i]) {
+				cdev->hbas[i]->vdev = vdev;
+				rcu_read_unlock();
+				if (port)
+					*port = i;
+				return cdev;
+			}
+		}
+	}
+	rcu_read_unlock();
+
+	log_debug(1 << CXGBI_DBG_DEV,
+		  "ndev 0x%p, %s, NO match found.\n", ndev, ndev->name);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(cxgbi_device_find_by_netdev_rcu);
+
+#if IS_ENABLED(CONFIG_IPV6)
+static struct cxgbi_device *cxgbi_device_find_by_mac(struct net_device *ndev,
+						     int *port)
+{
+	struct net_device *vdev = NULL;
+	struct cxgbi_device *cdev, *tmp;
+	int i;
+
+	if (is_vlan_dev(ndev)) {
+		vdev = ndev;
+		ndev = vlan_dev_real_dev(ndev);
+		pr_info("vlan dev %s -> %s.\n", vdev->name, ndev->name);
+	}
+
+	mutex_lock(&cdev_mutex);
+	list_for_each_entry_safe(cdev, tmp, &cdev_list, list_head) {
+		for (i = 0; i < cdev->nports; i++) {
+			if (!memcmp(ndev->dev_addr, cdev->ports[i]->dev_addr,
+				    MAX_ADDR_LEN)) {
+				cdev->hbas[i]->vdev = vdev;
+				mutex_unlock(&cdev_mutex);
+				if (port)
+					*port = i;
+				return cdev;
+			}
+		}
+	}
+	mutex_unlock(&cdev_mutex);
+	log_debug(1 << CXGBI_DBG_DEV,
+		  "ndev 0x%p, %s, NO match mac found.\n",
+		  ndev, ndev->name);
+	return NULL;
+}
+#endif
+
+void cxgbi_hbas_remove(struct cxgbi_device *cdev)
+{
+	int i;
+	struct cxgbi_hba *chba;
+
+	log_debug(1 << CXGBI_DBG_DEV,
+		"cdev 0x%p, p#%u.\n", cdev, cdev->nports);
+
+	for (i = 0; i < cdev->nports; i++) {
+		chba = cdev->hbas[i];
+		if (chba) {
+			cdev->hbas[i] = NULL;
+			iscsi_host_remove(chba->shost);
+			pci_dev_put(cdev->pdev);
+			iscsi_host_free(chba->shost);
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(cxgbi_hbas_remove);
+
+int cxgbi_hbas_add(struct cxgbi_device *cdev, u64 max_lun,
+		unsigned int max_conns, struct scsi_host_template *sht,
+		struct scsi_transport_template *stt)
+{
+	struct cxgbi_hba *chba;
+	struct Scsi_Host *shost;
+	int i, err;
+
+	log_debug(1 << CXGBI_DBG_DEV, "cdev 0x%p, p#%u.\n", cdev, cdev->nports);
+
+	for (i = 0; i < cdev->nports; i++) {
+		shost = iscsi_host_alloc(sht, sizeof(*chba), 1);
+		if (!shost) {
+			pr_info("0x%p, p%d, %s, host alloc failed.\n",
+				cdev, i, cdev->ports[i]->name);
+			err = -ENOMEM;
+			goto err_out;
+		}
+
+		shost->transportt = stt;
+		shost->max_lun = max_lun;
+		shost->max_id = max_conns - 1;
+		shost->max_channel = 0;
+		shost->max_cmd_len = 16;
+
+		chba = iscsi_host_priv(shost);
+		chba->cdev = cdev;
+		chba->ndev = cdev->ports[i];
+		chba->shost = shost;
+
+		log_debug(1 << CXGBI_DBG_DEV,
+			"cdev 0x%p, p#%d %s: chba 0x%p.\n",
+			cdev, i, cdev->ports[i]->name, chba);
+
+		pci_dev_get(cdev->pdev);
+		err = iscsi_host_add(shost, &cdev->pdev->dev);
+		if (err) {
+			pr_info("cdev 0x%p, p#%d %s, host add failed.\n",
+				cdev, i, cdev->ports[i]->name);
+			pci_dev_put(cdev->pdev);
+			scsi_host_put(shost);
+			goto  err_out;
+		}
+
+		cdev->hbas[i] = chba;
+	}
+
+	return 0;
+
+err_out:
+	cxgbi_hbas_remove(cdev);
+	return err;
+}
+EXPORT_SYMBOL_GPL(cxgbi_hbas_add);
+
+/*
+ * iSCSI offload
+ *
+ * - source port management
+ *   To find a free source port in the port allocation map we use a very simple
+ *   rotor scheme to look for the next free port.
+ *
+ *   If a source port has been specified make sure that it doesn't collide with
+ *   our normal source port allocation map.  If it's outside the range of our
+ *   allocation/deallocation scheme just let them use it.
+ *
+ *   If the source port is outside our allocation range, the caller is
+ *   responsible for keeping track of their port usage.
+ */
+
+static struct cxgbi_sock *find_sock_on_port(struct cxgbi_device *cdev,
+					    unsigned char port_id)
+{
+	struct cxgbi_ports_map *pmap = &cdev->pmap;
+	unsigned int i;
+	unsigned int used;
+
+	if (!pmap->max_connect || !pmap->used)
+		return NULL;
+
+	spin_lock_bh(&pmap->lock);
+	used = pmap->used;
+	for (i = 0; used && i < pmap->max_connect; i++) {
+		struct cxgbi_sock *csk = pmap->port_csk[i];
+
+		if (csk) {
+			if (csk->port_id == port_id) {
+				spin_unlock_bh(&pmap->lock);
+				return csk;
+			}
+			used--;
+		}
+	}
+	spin_unlock_bh(&pmap->lock);
+
+	return NULL;
+}
+
+static int sock_get_port(struct cxgbi_sock *csk)
+{
+	struct cxgbi_device *cdev = csk->cdev;
+	struct cxgbi_ports_map *pmap = &cdev->pmap;
+	unsigned int start;
+	int idx;
+	__be16 *port;
+
+	if (!pmap->max_connect) {
+		pr_err("cdev 0x%p, p#%u %s, NO port map.\n",
+			   cdev, csk->port_id, cdev->ports[csk->port_id]->name);
+		return -EADDRNOTAVAIL;
+	}
+
+	if (csk->csk_family == AF_INET)
+		port = &csk->saddr.sin_port;
+	else /* ipv6 */
+		port = &csk->saddr6.sin6_port;
+
+	if (*port) {
+		pr_err("source port NON-ZERO %u.\n",
+			ntohs(*port));
+		return -EADDRINUSE;
+	}
+
+	spin_lock_bh(&pmap->lock);
+	if (pmap->used >= pmap->max_connect) {
+		spin_unlock_bh(&pmap->lock);
+		pr_info("cdev 0x%p, p#%u %s, ALL ports used.\n",
+			cdev, csk->port_id, cdev->ports[csk->port_id]->name);
+		return -EADDRNOTAVAIL;
+	}
+
+	start = idx = pmap->next;
+	do {
+		if (++idx >= pmap->max_connect)
+			idx = 0;
+		if (!pmap->port_csk[idx]) {
+			pmap->used++;
+			*port = htons(pmap->sport_base + idx);
+			pmap->next = idx;
+			pmap->port_csk[idx] = csk;
+			spin_unlock_bh(&pmap->lock);
+			cxgbi_sock_get(csk);
+			log_debug(1 << CXGBI_DBG_SOCK,
+				"cdev 0x%p, p#%u %s, p %u, %u.\n",
+				cdev, csk->port_id,
+				cdev->ports[csk->port_id]->name,
+				pmap->sport_base + idx, pmap->next);
+			return 0;
+		}
+	} while (idx != start);
+	spin_unlock_bh(&pmap->lock);
+
+	/* should not happen */
+	pr_warn("cdev 0x%p, p#%u %s, next %u?\n",
+		cdev, csk->port_id, cdev->ports[csk->port_id]->name,
+		pmap->next);
+	return -EADDRNOTAVAIL;
+}
+
+static void sock_put_port(struct cxgbi_sock *csk)
+{
+	struct cxgbi_device *cdev = csk->cdev;
+	struct cxgbi_ports_map *pmap = &cdev->pmap;
+	__be16 *port;
+
+	if (csk->csk_family == AF_INET)
+		port = &csk->saddr.sin_port;
+	else /* ipv6 */
+		port = &csk->saddr6.sin6_port;
+
+	if (*port) {
+		int idx = ntohs(*port) - pmap->sport_base;
+
+		*port = 0;
+		if (idx < 0 || idx >= pmap->max_connect) {
+			pr_err("cdev 0x%p, p#%u %s, port %u OOR.\n",
+				cdev, csk->port_id,
+				cdev->ports[csk->port_id]->name,
+				ntohs(*port));
+			return;
+		}
+
+		spin_lock_bh(&pmap->lock);
+		pmap->port_csk[idx] = NULL;
+		pmap->used--;
+		spin_unlock_bh(&pmap->lock);
+
+		log_debug(1 << CXGBI_DBG_SOCK,
+			"cdev 0x%p, p#%u %s, release %u.\n",
+			cdev, csk->port_id, cdev->ports[csk->port_id]->name,
+			pmap->sport_base + idx);
+
+		cxgbi_sock_put(csk);
+	}
+}
+
+/*
+ * iscsi tcp connection
+ */
+void cxgbi_sock_free_cpl_skbs(struct cxgbi_sock *csk)
+{
+	if (csk->cpl_close) {
+		kfree_skb(csk->cpl_close);
+		csk->cpl_close = NULL;
+	}
+	if (csk->cpl_abort_req) {
+		kfree_skb(csk->cpl_abort_req);
+		csk->cpl_abort_req = NULL;
+	}
+	if (csk->cpl_abort_rpl) {
+		kfree_skb(csk->cpl_abort_rpl);
+		csk->cpl_abort_rpl = NULL;
+	}
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_free_cpl_skbs);
+
+static struct cxgbi_sock *cxgbi_sock_create(struct cxgbi_device *cdev)
+{
+	struct cxgbi_sock *csk = kzalloc(sizeof(*csk), GFP_NOIO);
+
+	if (!csk) {
+		pr_info("alloc csk %zu failed.\n", sizeof(*csk));
+		return NULL;
+	}
+
+	if (cdev->csk_alloc_cpls(csk) < 0) {
+		pr_info("csk 0x%p, alloc cpls failed.\n", csk);
+		kfree(csk);
+		return NULL;
+	}
+
+	spin_lock_init(&csk->lock);
+	kref_init(&csk->refcnt);
+	skb_queue_head_init(&csk->receive_queue);
+	skb_queue_head_init(&csk->write_queue);
+	timer_setup(&csk->retry_timer, NULL, 0);
+	init_completion(&csk->cmpl);
+	rwlock_init(&csk->callback_lock);
+	csk->cdev = cdev;
+	csk->flags = 0;
+	cxgbi_sock_set_state(csk, CTP_CLOSED);
+
+	log_debug(1 << CXGBI_DBG_SOCK, "cdev 0x%p, new csk 0x%p.\n", cdev, csk);
+
+	return csk;
+}
+
+static struct rtable *find_route_ipv4(struct flowi4 *fl4,
+				      __be32 saddr, __be32 daddr,
+				      __be16 sport, __be16 dport, u8 tos,
+				      int ifindex)
+{
+	struct rtable *rt;
+
+	rt = ip_route_output_ports(&init_net, fl4, NULL, daddr, saddr,
+				   dport, sport, IPPROTO_TCP, tos, ifindex);
+	if (IS_ERR(rt))
+		return NULL;
+
+	return rt;
+}
+
+static struct cxgbi_sock *
+cxgbi_check_route(struct sockaddr *dst_addr, int ifindex)
+{
+	struct sockaddr_in *daddr = (struct sockaddr_in *)dst_addr;
+	struct dst_entry *dst;
+	struct net_device *ndev;
+	struct cxgbi_device *cdev;
+	struct rtable *rt = NULL;
+	struct neighbour *n;
+	struct flowi4 fl4;
+	struct cxgbi_sock *csk = NULL;
+	unsigned int mtu = 0;
+	int port = 0xFFFF;
+	int err = 0;
+
+	rt = find_route_ipv4(&fl4, 0, daddr->sin_addr.s_addr, 0,
+			     daddr->sin_port, 0, ifindex);
+	if (!rt) {
+		pr_info("no route to ipv4 0x%x, port %u.\n",
+			be32_to_cpu(daddr->sin_addr.s_addr),
+			be16_to_cpu(daddr->sin_port));
+		err = -ENETUNREACH;
+		goto err_out;
+	}
+	dst = &rt->dst;
+	n = dst_neigh_lookup(dst, &daddr->sin_addr.s_addr);
+	if (!n) {
+		err = -ENODEV;
+		goto rel_rt;
+	}
+	ndev = n->dev;
+
+	if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) {
+		pr_info("multi-cast route %pI4, port %u, dev %s.\n",
+			&daddr->sin_addr.s_addr, ntohs(daddr->sin_port),
+			ndev->name);
+		err = -ENETUNREACH;
+		goto rel_neigh;
+	}
+
+	if (ndev->flags & IFF_LOOPBACK) {
+		ndev = ip_dev_find(&init_net, daddr->sin_addr.s_addr);
+		if (!ndev) {
+			err = -ENETUNREACH;
+			goto rel_neigh;
+		}
+		mtu = ndev->mtu;
+		pr_info("rt dev %s, loopback -> %s, mtu %u.\n",
+			n->dev->name, ndev->name, mtu);
+	}
+
+	if (!(ndev->flags & IFF_UP) || !netif_carrier_ok(ndev)) {
+		pr_info("%s interface not up.\n", ndev->name);
+		err = -ENETDOWN;
+		goto rel_neigh;
+	}
+
+	cdev = cxgbi_device_find_by_netdev(ndev, &port);
+	if (!cdev) {
+		pr_info("dst %pI4, %s, NOT cxgbi device.\n",
+			&daddr->sin_addr.s_addr, ndev->name);
+		err = -ENETUNREACH;
+		goto rel_neigh;
+	}
+	log_debug(1 << CXGBI_DBG_SOCK,
+		"route to %pI4 :%u, ndev p#%d,%s, cdev 0x%p.\n",
+		&daddr->sin_addr.s_addr, ntohs(daddr->sin_port),
+			   port, ndev->name, cdev);
+
+	csk = cxgbi_sock_create(cdev);
+	if (!csk) {
+		err = -ENOMEM;
+		goto rel_neigh;
+	}
+	csk->cdev = cdev;
+	csk->port_id = port;
+	csk->mtu = mtu;
+	csk->dst = dst;
+
+	csk->csk_family = AF_INET;
+	csk->daddr.sin_addr.s_addr = daddr->sin_addr.s_addr;
+	csk->daddr.sin_port = daddr->sin_port;
+	csk->daddr.sin_family = daddr->sin_family;
+	csk->saddr.sin_family = daddr->sin_family;
+	csk->saddr.sin_addr.s_addr = fl4.saddr;
+	neigh_release(n);
+
+	return csk;
+
+rel_neigh:
+	neigh_release(n);
+
+rel_rt:
+	ip_rt_put(rt);
+err_out:
+	return ERR_PTR(err);
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static struct rt6_info *find_route_ipv6(const struct in6_addr *saddr,
+					const struct in6_addr *daddr,
+					int ifindex)
+{
+	struct flowi6 fl;
+
+	memset(&fl, 0, sizeof(fl));
+	fl.flowi6_oif = ifindex;
+	if (saddr)
+		memcpy(&fl.saddr, saddr, sizeof(struct in6_addr));
+	if (daddr)
+		memcpy(&fl.daddr, daddr, sizeof(struct in6_addr));
+	return (struct rt6_info *)ip6_route_output(&init_net, NULL, &fl);
+}
+
+static struct cxgbi_sock *
+cxgbi_check_route6(struct sockaddr *dst_addr, int ifindex)
+{
+	struct sockaddr_in6 *daddr6 = (struct sockaddr_in6 *)dst_addr;
+	struct dst_entry *dst;
+	struct net_device *ndev;
+	struct cxgbi_device *cdev;
+	struct rt6_info *rt = NULL;
+	struct neighbour *n;
+	struct in6_addr pref_saddr;
+	struct cxgbi_sock *csk = NULL;
+	unsigned int mtu = 0;
+	int port = 0xFFFF;
+	int err = 0;
+
+	rt = find_route_ipv6(NULL, &daddr6->sin6_addr, ifindex);
+
+	if (!rt) {
+		pr_info("no route to ipv6 %pI6 port %u\n",
+			daddr6->sin6_addr.s6_addr,
+			be16_to_cpu(daddr6->sin6_port));
+		err = -ENETUNREACH;
+		goto err_out;
+	}
+
+	dst = &rt->dst;
+
+	n = dst_neigh_lookup(dst, &daddr6->sin6_addr);
+
+	if (!n) {
+		pr_info("%pI6, port %u, dst no neighbour.\n",
+			daddr6->sin6_addr.s6_addr,
+			be16_to_cpu(daddr6->sin6_port));
+		err = -ENETUNREACH;
+		goto rel_rt;
+	}
+	ndev = n->dev;
+
+	if (!(ndev->flags & IFF_UP) || !netif_carrier_ok(ndev)) {
+		pr_info("%s interface not up.\n", ndev->name);
+		err = -ENETDOWN;
+		goto rel_rt;
+	}
+
+	if (ipv6_addr_is_multicast(&daddr6->sin6_addr)) {
+		pr_info("multi-cast route %pI6 port %u, dev %s.\n",
+			daddr6->sin6_addr.s6_addr,
+			ntohs(daddr6->sin6_port), ndev->name);
+		err = -ENETUNREACH;
+		goto rel_rt;
+	}
+
+	cdev = cxgbi_device_find_by_netdev(ndev, &port);
+	if (!cdev)
+		cdev = cxgbi_device_find_by_mac(ndev, &port);
+	if (!cdev) {
+		pr_info("dst %pI6 %s, NOT cxgbi device.\n",
+			daddr6->sin6_addr.s6_addr, ndev->name);
+		err = -ENETUNREACH;
+		goto rel_rt;
+	}
+	log_debug(1 << CXGBI_DBG_SOCK,
+		  "route to %pI6 :%u, ndev p#%d,%s, cdev 0x%p.\n",
+		  daddr6->sin6_addr.s6_addr, ntohs(daddr6->sin6_port), port,
+		  ndev->name, cdev);
+
+	csk = cxgbi_sock_create(cdev);
+	if (!csk) {
+		err = -ENOMEM;
+		goto rel_rt;
+	}
+	csk->cdev = cdev;
+	csk->port_id = port;
+	csk->mtu = mtu;
+	csk->dst = dst;
+
+	if (ipv6_addr_any(&rt->rt6i_prefsrc.addr)) {
+		struct inet6_dev *idev = ip6_dst_idev((struct dst_entry *)rt);
+
+		err = ipv6_dev_get_saddr(&init_net, idev ? idev->dev : NULL,
+					 &daddr6->sin6_addr, 0, &pref_saddr);
+		if (err) {
+			pr_info("failed to get source address to reach %pI6\n",
+				&daddr6->sin6_addr);
+			goto rel_rt;
+		}
+	} else {
+		pref_saddr = rt->rt6i_prefsrc.addr;
+	}
+
+	csk->csk_family = AF_INET6;
+	csk->daddr6.sin6_addr = daddr6->sin6_addr;
+	csk->daddr6.sin6_port = daddr6->sin6_port;
+	csk->daddr6.sin6_family = daddr6->sin6_family;
+	csk->saddr6.sin6_family = daddr6->sin6_family;
+	csk->saddr6.sin6_addr = pref_saddr;
+
+	neigh_release(n);
+	return csk;
+
+rel_rt:
+	if (n)
+		neigh_release(n);
+
+	ip6_rt_put(rt);
+	if (csk)
+		cxgbi_sock_closed(csk);
+err_out:
+	return ERR_PTR(err);
+}
+#endif /* IS_ENABLED(CONFIG_IPV6) */
+
+void cxgbi_sock_established(struct cxgbi_sock *csk, unsigned int snd_isn,
+			unsigned int opt)
+{
+	csk->write_seq = csk->snd_nxt = csk->snd_una = snd_isn;
+	dst_confirm(csk->dst);
+	smp_mb();
+	cxgbi_sock_set_state(csk, CTP_ESTABLISHED);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_established);
+
+static void cxgbi_inform_iscsi_conn_closing(struct cxgbi_sock *csk)
+{
+	log_debug(1 << CXGBI_DBG_SOCK,
+		"csk 0x%p, state %u, flags 0x%lx, conn 0x%p.\n",
+		csk, csk->state, csk->flags, csk->user_data);
+
+	if (csk->state != CTP_ESTABLISHED) {
+		read_lock_bh(&csk->callback_lock);
+		if (csk->user_data)
+			iscsi_conn_failure(csk->user_data,
+					ISCSI_ERR_TCP_CONN_CLOSE);
+		read_unlock_bh(&csk->callback_lock);
+	}
+}
+
+void cxgbi_sock_closed(struct cxgbi_sock *csk)
+{
+	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
+		csk, (csk)->state, (csk)->flags, (csk)->tid);
+	cxgbi_sock_set_flag(csk, CTPF_ACTIVE_CLOSE_NEEDED);
+	if (csk->state == CTP_ACTIVE_OPEN || csk->state == CTP_CLOSED)
+		return;
+	if (csk->saddr.sin_port)
+		sock_put_port(csk);
+	if (csk->dst)
+		dst_release(csk->dst);
+	csk->cdev->csk_release_offload_resources(csk);
+	cxgbi_sock_set_state(csk, CTP_CLOSED);
+	cxgbi_inform_iscsi_conn_closing(csk);
+	cxgbi_sock_put(csk);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_closed);
+
+static void need_active_close(struct cxgbi_sock *csk)
+{
+	int data_lost;
+	int close_req = 0;
+
+	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
+		csk, (csk)->state, (csk)->flags, (csk)->tid);
+	spin_lock_bh(&csk->lock);
+	if (csk->dst)
+		dst_confirm(csk->dst);
+	data_lost = skb_queue_len(&csk->receive_queue);
+	__skb_queue_purge(&csk->receive_queue);
+
+	if (csk->state == CTP_ACTIVE_OPEN)
+		cxgbi_sock_set_flag(csk, CTPF_ACTIVE_CLOSE_NEEDED);
+	else if (csk->state == CTP_ESTABLISHED) {
+		close_req = 1;
+		cxgbi_sock_set_state(csk, CTP_ACTIVE_CLOSE);
+	} else if (csk->state == CTP_PASSIVE_CLOSE) {
+		close_req = 1;
+		cxgbi_sock_set_state(csk, CTP_CLOSE_WAIT_2);
+	}
+
+	if (close_req) {
+		if (!cxgbi_sock_flag(csk, CTPF_LOGOUT_RSP_RCVD) ||
+		    data_lost)
+			csk->cdev->csk_send_abort_req(csk);
+		else
+			csk->cdev->csk_send_close_req(csk);
+	}
+
+	spin_unlock_bh(&csk->lock);
+}
+
+void cxgbi_sock_fail_act_open(struct cxgbi_sock *csk, int errno)
+{
+	pr_info("csk 0x%p,%u,%lx, %pI4:%u-%pI4:%u, err %d.\n",
+			csk, csk->state, csk->flags,
+			&csk->saddr.sin_addr.s_addr, csk->saddr.sin_port,
+			&csk->daddr.sin_addr.s_addr, csk->daddr.sin_port,
+			errno);
+
+	cxgbi_sock_set_state(csk, CTP_CONNECTING);
+	csk->err = errno;
+	cxgbi_sock_closed(csk);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_fail_act_open);
+
+void cxgbi_sock_act_open_req_arp_failure(void *handle, struct sk_buff *skb)
+{
+	struct cxgbi_sock *csk = (struct cxgbi_sock *)skb->sk;
+	struct module *owner = csk->cdev->owner;
+
+	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
+		csk, (csk)->state, (csk)->flags, (csk)->tid);
+	cxgbi_sock_get(csk);
+	spin_lock_bh(&csk->lock);
+	if (csk->state == CTP_ACTIVE_OPEN)
+		cxgbi_sock_fail_act_open(csk, -EHOSTUNREACH);
+	spin_unlock_bh(&csk->lock);
+	cxgbi_sock_put(csk);
+	__kfree_skb(skb);
+
+	module_put(owner);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_act_open_req_arp_failure);
+
+void cxgbi_sock_rcv_abort_rpl(struct cxgbi_sock *csk)
+{
+	cxgbi_sock_get(csk);
+	spin_lock_bh(&csk->lock);
+
+	cxgbi_sock_set_flag(csk, CTPF_ABORT_RPL_RCVD);
+	if (cxgbi_sock_flag(csk, CTPF_ABORT_RPL_PENDING)) {
+		cxgbi_sock_clear_flag(csk, CTPF_ABORT_RPL_PENDING);
+		if (cxgbi_sock_flag(csk, CTPF_ABORT_REQ_RCVD))
+			pr_err("csk 0x%p,%u,0x%lx,%u,ABT_RPL_RSS.\n",
+			       csk, csk->state, csk->flags, csk->tid);
+		cxgbi_sock_closed(csk);
+	}
+
+	spin_unlock_bh(&csk->lock);
+	cxgbi_sock_put(csk);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_abort_rpl);
+
+void cxgbi_sock_rcv_peer_close(struct cxgbi_sock *csk)
+{
+	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
+		csk, (csk)->state, (csk)->flags, (csk)->tid);
+	cxgbi_sock_get(csk);
+	spin_lock_bh(&csk->lock);
+
+	if (cxgbi_sock_flag(csk, CTPF_ABORT_RPL_PENDING))
+		goto done;
+
+	switch (csk->state) {
+	case CTP_ESTABLISHED:
+		cxgbi_sock_set_state(csk, CTP_PASSIVE_CLOSE);
+		break;
+	case CTP_ACTIVE_CLOSE:
+		cxgbi_sock_set_state(csk, CTP_CLOSE_WAIT_2);
+		break;
+	case CTP_CLOSE_WAIT_1:
+		cxgbi_sock_closed(csk);
+		break;
+	case CTP_ABORTING:
+		break;
+	default:
+		pr_err("csk 0x%p,%u,0x%lx,%u, bad state.\n",
+			csk, csk->state, csk->flags, csk->tid);
+	}
+	cxgbi_inform_iscsi_conn_closing(csk);
+done:
+	spin_unlock_bh(&csk->lock);
+	cxgbi_sock_put(csk);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_peer_close);
+
+void cxgbi_sock_rcv_close_conn_rpl(struct cxgbi_sock *csk, u32 snd_nxt)
+{
+	log_debug(1 << CXGBI_DBG_SOCK, "csk 0x%p,%u,0x%lx,%u.\n",
+		csk, (csk)->state, (csk)->flags, (csk)->tid);
+	cxgbi_sock_get(csk);
+	spin_lock_bh(&csk->lock);
+
+	csk->snd_una = snd_nxt - 1;
+	if (cxgbi_sock_flag(csk, CTPF_ABORT_RPL_PENDING))
+		goto done;
+
+	switch (csk->state) {
+	case CTP_ACTIVE_CLOSE:
+		cxgbi_sock_set_state(csk, CTP_CLOSE_WAIT_1);
+		break;
+	case CTP_CLOSE_WAIT_1:
+	case CTP_CLOSE_WAIT_2:
+		cxgbi_sock_closed(csk);
+		break;
+	case CTP_ABORTING:
+		break;
+	default:
+		pr_err("csk 0x%p,%u,0x%lx,%u, bad state.\n",
+			csk, csk->state, csk->flags, csk->tid);
+	}
+done:
+	spin_unlock_bh(&csk->lock);
+	cxgbi_sock_put(csk);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_close_conn_rpl);
+
+void cxgbi_sock_rcv_wr_ack(struct cxgbi_sock *csk, unsigned int credits,
+			   unsigned int snd_una, int seq_chk)
+{
+	log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
+			"csk 0x%p,%u,0x%lx,%u, cr %u,%u+%u, snd_una %u,%d.\n",
+			csk, csk->state, csk->flags, csk->tid, credits,
+			csk->wr_cred, csk->wr_una_cred, snd_una, seq_chk);
+
+	spin_lock_bh(&csk->lock);
+
+	csk->wr_cred += credits;
+	if (csk->wr_una_cred > csk->wr_max_cred - csk->wr_cred)
+		csk->wr_una_cred = csk->wr_max_cred - csk->wr_cred;
+
+	while (credits) {
+		struct sk_buff *p = cxgbi_sock_peek_wr(csk);
+
+		if (unlikely(!p)) {
+			pr_err("csk 0x%p,%u,0x%lx,%u, cr %u,%u+%u, empty.\n",
+				csk, csk->state, csk->flags, csk->tid, credits,
+				csk->wr_cred, csk->wr_una_cred);
+			break;
+		}
+
+		if (unlikely(credits < p->csum)) {
+			pr_warn("csk 0x%p,%u,0x%lx,%u, cr %u,%u+%u, < %u.\n",
+				csk, csk->state, csk->flags, csk->tid,
+				credits, csk->wr_cred, csk->wr_una_cred,
+				p->csum);
+			p->csum -= credits;
+			break;
+		} else {
+			cxgbi_sock_dequeue_wr(csk);
+			credits -= p->csum;
+			kfree_skb(p);
+		}
+	}
+
+	cxgbi_sock_check_wr_invariants(csk);
+
+	if (seq_chk) {
+		if (unlikely(before(snd_una, csk->snd_una))) {
+			pr_warn("csk 0x%p,%u,0x%lx,%u, snd_una %u/%u.",
+				csk, csk->state, csk->flags, csk->tid, snd_una,
+				csk->snd_una);
+			goto done;
+		}
+
+		if (csk->snd_una != snd_una) {
+			csk->snd_una = snd_una;
+			dst_confirm(csk->dst);
+		}
+	}
+
+	if (skb_queue_len(&csk->write_queue)) {
+		if (csk->cdev->csk_push_tx_frames(csk, 0))
+			cxgbi_conn_tx_open(csk);
+	} else
+		cxgbi_conn_tx_open(csk);
+done:
+	spin_unlock_bh(&csk->lock);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_rcv_wr_ack);
+
+static unsigned int cxgbi_sock_find_best_mtu(struct cxgbi_sock *csk,
+					     unsigned short mtu)
+{
+	int i = 0;
+
+	while (i < csk->cdev->nmtus - 1 && csk->cdev->mtus[i + 1] <= mtu)
+		++i;
+
+	return i;
+}
+
+unsigned int cxgbi_sock_select_mss(struct cxgbi_sock *csk, unsigned int pmtu)
+{
+	unsigned int idx;
+	struct dst_entry *dst = csk->dst;
+
+	csk->advmss = dst_metric_advmss(dst);
+
+	if (csk->advmss > pmtu - 40)
+		csk->advmss = pmtu - 40;
+	if (csk->advmss < csk->cdev->mtus[0] - 40)
+		csk->advmss = csk->cdev->mtus[0] - 40;
+	idx = cxgbi_sock_find_best_mtu(csk, csk->advmss + 40);
+
+	return idx;
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_select_mss);
+
+void cxgbi_sock_skb_entail(struct cxgbi_sock *csk, struct sk_buff *skb)
+{
+	cxgbi_skcb_tcp_seq(skb) = csk->write_seq;
+	__skb_queue_tail(&csk->write_queue, skb);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_skb_entail);
+
+void cxgbi_sock_purge_wr_queue(struct cxgbi_sock *csk)
+{
+	struct sk_buff *skb;
+
+	while ((skb = cxgbi_sock_dequeue_wr(csk)) != NULL)
+		kfree_skb(skb);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_purge_wr_queue);
+
+void cxgbi_sock_check_wr_invariants(const struct cxgbi_sock *csk)
+{
+	int pending = cxgbi_sock_count_pending_wrs(csk);
+
+	if (unlikely(csk->wr_cred + pending != csk->wr_max_cred))
+		pr_err("csk 0x%p, tid %u, credit %u + %u != %u.\n",
+			csk, csk->tid, csk->wr_cred, pending, csk->wr_max_cred);
+}
+EXPORT_SYMBOL_GPL(cxgbi_sock_check_wr_invariants);
+
+static int cxgbi_sock_send_pdus(struct cxgbi_sock *csk, struct sk_buff *skb)
+{
+	struct cxgbi_device *cdev = csk->cdev;
+	struct sk_buff *next;
+	int err, copied = 0;
+
+	spin_lock_bh(&csk->lock);
+
+	if (csk->state != CTP_ESTABLISHED) {
+		log_debug(1 << CXGBI_DBG_PDU_TX,
+			"csk 0x%p,%u,0x%lx,%u, EAGAIN.\n",
+			csk, csk->state, csk->flags, csk->tid);
+		err = -EAGAIN;
+		goto out_err;
+	}
+
+	if (csk->err) {
+		log_debug(1 << CXGBI_DBG_PDU_TX,
+			"csk 0x%p,%u,0x%lx,%u, EPIPE %d.\n",
+			csk, csk->state, csk->flags, csk->tid, csk->err);
+		err = -EPIPE;
+		goto out_err;
+	}
+
+	if (csk->write_seq - csk->snd_una >= csk->snd_win) {
+		log_debug(1 << CXGBI_DBG_PDU_TX,
+			"csk 0x%p,%u,0x%lx,%u, FULL %u-%u >= %u.\n",
+			csk, csk->state, csk->flags, csk->tid, csk->write_seq,
+			csk->snd_una, csk->snd_win);
+		err = -ENOBUFS;
+		goto out_err;
+	}
+
+	while (skb) {
+		int frags = skb_shinfo(skb)->nr_frags +
+				(skb->len != skb->data_len);
+
+		if (unlikely(skb_headroom(skb) < cdev->skb_tx_rsvd)) {
+			pr_err("csk 0x%p, skb head %u < %u.\n",
+				csk, skb_headroom(skb), cdev->skb_tx_rsvd);
+			err = -EINVAL;
+			goto out_err;
+		}
+
+		if (frags >= SKB_WR_LIST_SIZE) {
+			pr_err("csk 0x%p, frags %d, %u,%u >%u.\n",
+				csk, skb_shinfo(skb)->nr_frags, skb->len,
+				skb->data_len, (uint)(SKB_WR_LIST_SIZE));
+			err = -EINVAL;
+			goto out_err;
+		}
+
+		next = skb->next;
+		skb->next = NULL;
+		cxgbi_skcb_set_flag(skb, SKCBF_TX_NEED_HDR);
+		cxgbi_sock_skb_entail(csk, skb);
+		copied += skb->len;
+		csk->write_seq += skb->len +
+				cxgbi_ulp_extra_len(cxgbi_skcb_ulp_mode(skb));
+		skb = next;
+	}
+
+	if (likely(skb_queue_len(&csk->write_queue)))
+		cdev->csk_push_tx_frames(csk, 1);
+done:
+	spin_unlock_bh(&csk->lock);
+	return copied;
+
+out_err:
+	if (copied == 0 && err == -EPIPE)
+		copied = csk->err ? csk->err : -EPIPE;
+	else
+		copied = err;
+	goto done;
+}
+
+static inline void
+scmd_get_params(struct scsi_cmnd *sc, struct scatterlist **sgl,
+		unsigned int *sgcnt, unsigned int *dlen,
+		unsigned int prot)
+{
+	struct scsi_data_buffer *sdb = prot ? scsi_prot(sc) : scsi_out(sc);
+
+	*sgl = sdb->table.sgl;
+	*sgcnt = sdb->table.nents;
+	*dlen = sdb->length;
+	/* Caution: for protection sdb, sdb->length is invalid */
+}
+
+void cxgbi_ddp_set_one_ppod(struct cxgbi_pagepod *ppod,
+			    struct cxgbi_task_tag_info *ttinfo,
+			    struct scatterlist **sg_pp, unsigned int *sg_off)
+{
+	struct scatterlist *sg = sg_pp ? *sg_pp : NULL;
+	unsigned int offset = sg_off ? *sg_off : 0;
+	dma_addr_t addr = 0UL;
+	unsigned int len = 0;
+	int i;
+
+	memcpy(ppod, &ttinfo->hdr, sizeof(struct cxgbi_pagepod_hdr));
+
+	if (sg) {
+		addr = sg_dma_address(sg);
+		len = sg_dma_len(sg);
+	}
+
+	for (i = 0; i < PPOD_PAGES_MAX; i++) {
+		if (sg) {
+			ppod->addr[i] = cpu_to_be64(addr + offset);
+			offset += PAGE_SIZE;
+			if (offset == (len + sg->offset)) {
+				offset = 0;
+				sg = sg_next(sg);
+				if (sg) {
+					addr = sg_dma_address(sg);
+					len = sg_dma_len(sg);
+				}
+			}
+		} else {
+			ppod->addr[i] = 0ULL;
+		}
+	}
+
+	/*
+	 * the fifth address needs to be repeated in the next ppod, so do
+	 * not move sg
+	 */
+	if (sg_pp) {
+		*sg_pp = sg;
+		*sg_off = offset;
+	}
+
+	if (offset == len) {
+		offset = 0;
+		sg = sg_next(sg);
+		if (sg) {
+			addr = sg_dma_address(sg);
+			len = sg_dma_len(sg);
+		}
+	}
+	ppod->addr[i] = sg ? cpu_to_be64(addr + offset) : 0ULL;
+}
+EXPORT_SYMBOL_GPL(cxgbi_ddp_set_one_ppod);
+
+/*
+ * APIs interacting with open-iscsi libraries
+ */
+
+static unsigned char padding[4];
+
+void cxgbi_ddp_ppm_setup(void **ppm_pp, struct cxgbi_device *cdev,
+			 struct cxgbi_tag_format *tformat, unsigned int ppmax,
+			 unsigned int llimit, unsigned int start,
+			 unsigned int rsvd_factor)
+{
+	int err = cxgbi_ppm_init(ppm_pp, cdev->ports[0], cdev->pdev,
+				cdev->lldev, tformat, ppmax, llimit, start,
+				rsvd_factor);
+
+	if (err >= 0) {
+		struct cxgbi_ppm *ppm = (struct cxgbi_ppm *)(*ppm_pp);
+
+		if (ppm->ppmax < 1024 ||
+		    ppm->tformat.pgsz_idx_dflt >= DDP_PGIDX_MAX)
+			cdev->flags |= CXGBI_FLAG_DDP_OFF;
+		err = 0;
+	} else {
+		cdev->flags |= CXGBI_FLAG_DDP_OFF;
+	}
+}
+EXPORT_SYMBOL_GPL(cxgbi_ddp_ppm_setup);
+
+static int cxgbi_ddp_sgl_check(struct scatterlist *sgl, int nents)
+{
+	int i;
+	int last_sgidx = nents - 1;
+	struct scatterlist *sg = sgl;
+
+	for (i = 0; i < nents; i++, sg = sg_next(sg)) {
+		unsigned int len = sg->length + sg->offset;
+
+		if ((sg->offset & 0x3) || (i && sg->offset) ||
+		    ((i != last_sgidx) && len != PAGE_SIZE)) {
+			log_debug(1 << CXGBI_DBG_DDP,
+				  "sg %u/%u, %u,%u, not aligned.\n",
+				  i, nents, sg->offset, sg->length);
+			goto err_out;
+		}
+	}
+	return 0;
+err_out:
+	return -EINVAL;
+}
+
+static int cxgbi_ddp_reserve(struct cxgbi_conn *cconn,
+			     struct cxgbi_task_data *tdata, u32 sw_tag,
+			     unsigned int xferlen)
+{
+	struct cxgbi_sock *csk = cconn->cep->csk;
+	struct cxgbi_device *cdev = csk->cdev;
+	struct cxgbi_ppm *ppm = cdev->cdev2ppm(cdev);
+	struct cxgbi_task_tag_info *ttinfo = &tdata->ttinfo;
+	struct scatterlist *sgl = ttinfo->sgl;
+	unsigned int sgcnt = ttinfo->nents;
+	unsigned int sg_offset = sgl->offset;
+	int err;
+
+	if (cdev->flags & CXGBI_FLAG_DDP_OFF) {
+		log_debug(1 << CXGBI_DBG_DDP,
+			  "cdev 0x%p DDP off.\n", cdev);
+		return -EINVAL;
+	}
+
+	if (!ppm || xferlen < DDP_THRESHOLD || !sgcnt ||
+	    ppm->tformat.pgsz_idx_dflt >= DDP_PGIDX_MAX) {
+		log_debug(1 << CXGBI_DBG_DDP,
+			  "ppm 0x%p, pgidx %u, xfer %u, sgcnt %u, NO ddp.\n",
+			  ppm, ppm ? ppm->tformat.pgsz_idx_dflt : DDP_PGIDX_MAX,
+			  xferlen, ttinfo->nents);
+		return -EINVAL;
+	}
+
+	/* make sure the buffer is suitable for ddp */
+	if (cxgbi_ddp_sgl_check(sgl, sgcnt) < 0)
+		return -EINVAL;
+
+	ttinfo->nr_pages = (xferlen + sgl->offset + (1 << PAGE_SHIFT) - 1) >>
+			    PAGE_SHIFT;
+
+	/*
+	 * the ddp tag will be used for the itt in the outgoing pdu,
+	 * the itt genrated by libiscsi is saved in the ppm and can be
+	 * retrieved via the ddp tag
+	 */
+	err = cxgbi_ppm_ppods_reserve(ppm, ttinfo->nr_pages, 0, &ttinfo->idx,
+				      &ttinfo->tag, (unsigned long)sw_tag);
+	if (err < 0) {
+		cconn->ddp_full++;
+		return err;
+	}
+	ttinfo->npods = err;
+
+	 /* setup dma from scsi command sgl */
+	sgl->offset = 0;
+	err = dma_map_sg(&ppm->pdev->dev, sgl, sgcnt, DMA_FROM_DEVICE);
+	sgl->offset = sg_offset;
+	if (err == 0) {
+		pr_info("%s: 0x%x, xfer %u, sgl %u dma mapping err.\n",
+			__func__, sw_tag, xferlen, sgcnt);
+		goto rel_ppods;
+	}
+	if (err != ttinfo->nr_pages) {
+		log_debug(1 << CXGBI_DBG_DDP,
+			  "%s: sw tag 0x%x, xfer %u, sgl %u, dma count %d.\n",
+			  __func__, sw_tag, xferlen, sgcnt, err);
+	}
+
+	ttinfo->flags |= CXGBI_PPOD_INFO_FLAG_MAPPED;
+	ttinfo->cid = csk->port_id;
+
+	cxgbi_ppm_make_ppod_hdr(ppm, ttinfo->tag, csk->tid, sgl->offset,
+				xferlen, &ttinfo->hdr);
+
+	if (cdev->flags & CXGBI_FLAG_USE_PPOD_OFLDQ) {
+		/* write ppod from xmit_pdu (of iscsi_scsi_command pdu) */
+		ttinfo->flags |= CXGBI_PPOD_INFO_FLAG_VALID;
+	} else {
+		/* write ppod from control queue now */
+		err = cdev->csk_ddp_set_map(ppm, csk, ttinfo);
+		if (err < 0)
+			goto rel_ppods;
+	}
+
+	return 0;
+
+rel_ppods:
+	cxgbi_ppm_ppod_release(ppm, ttinfo->idx);
+
+	if (ttinfo->flags & CXGBI_PPOD_INFO_FLAG_MAPPED) {
+		ttinfo->flags &= ~CXGBI_PPOD_INFO_FLAG_MAPPED;
+		dma_unmap_sg(&ppm->pdev->dev, sgl, sgcnt, DMA_FROM_DEVICE);
+	}
+	return -EINVAL;
+}
+
+static void task_release_itt(struct iscsi_task *task, itt_t hdr_itt)
+{
+	struct scsi_cmnd *sc = task->sc;
+	struct iscsi_tcp_conn *tcp_conn = task->conn->dd_data;
+	struct cxgbi_conn *cconn = tcp_conn->dd_data;
+	struct cxgbi_device *cdev = cconn->chba->cdev;
+	struct cxgbi_ppm *ppm = cdev->cdev2ppm(cdev);
+	u32 tag = ntohl((__force u32)hdr_itt);
+
+	log_debug(1 << CXGBI_DBG_DDP,
+		  "cdev 0x%p, task 0x%p, release tag 0x%x.\n",
+		  cdev, task, tag);
+	if (sc &&
+	    (scsi_bidi_cmnd(sc) || sc->sc_data_direction == DMA_FROM_DEVICE) &&
+	    cxgbi_ppm_is_ddp_tag(ppm, tag)) {
+		struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
+		struct cxgbi_task_tag_info *ttinfo = &tdata->ttinfo;
+
+		if (!(cdev->flags & CXGBI_FLAG_USE_PPOD_OFLDQ))
+			cdev->csk_ddp_clear_map(cdev, ppm, ttinfo);
+		cxgbi_ppm_ppod_release(ppm, ttinfo->idx);
+		dma_unmap_sg(&ppm->pdev->dev, ttinfo->sgl, ttinfo->nents,
+			     DMA_FROM_DEVICE);
+	}
+}
+
+static inline u32 cxgbi_build_sw_tag(u32 idx, u32 age)
+{
+	/* assume idx and age both are < 0x7FFF (32767) */
+	return (idx << 16) | age;
+}
+
+static int task_reserve_itt(struct iscsi_task *task, itt_t *hdr_itt)
+{
+	struct scsi_cmnd *sc = task->sc;
+	struct iscsi_conn *conn = task->conn;
+	struct iscsi_session *sess = conn->session;
+	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+	struct cxgbi_conn *cconn = tcp_conn->dd_data;
+	struct cxgbi_device *cdev = cconn->chba->cdev;
+	struct cxgbi_ppm *ppm = cdev->cdev2ppm(cdev);
+	u32 sw_tag = cxgbi_build_sw_tag(task->itt, sess->age);
+	u32 tag = 0;
+	int err = -EINVAL;
+
+	if (sc &&
+	    (scsi_bidi_cmnd(sc) || sc->sc_data_direction == DMA_FROM_DEVICE)
+	) {
+		struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
+		struct cxgbi_task_tag_info *ttinfo = &tdata->ttinfo;
+
+		scmd_get_params(sc, &ttinfo->sgl, &ttinfo->nents,
+				&tdata->dlen, 0);
+		err = cxgbi_ddp_reserve(cconn, tdata, sw_tag, tdata->dlen);
+		if (!err)
+			tag = ttinfo->tag;
+		else
+			 log_debug(1 << CXGBI_DBG_DDP,
+				   "csk 0x%p, R task 0x%p, %u,%u, no ddp.\n",
+				   cconn->cep->csk, task, tdata->dlen,
+				   ttinfo->nents);
+	}
+
+	if (err < 0) {
+		err = cxgbi_ppm_make_non_ddp_tag(ppm, sw_tag, &tag);
+		if (err < 0)
+			return err;
+	}
+	/*  the itt need to sent in big-endian order */
+	*hdr_itt = (__force itt_t)htonl(tag);
+
+	log_debug(1 << CXGBI_DBG_DDP,
+		  "cdev 0x%p, task 0x%p, 0x%x(0x%x,0x%x)->0x%x/0x%x.\n",
+		  cdev, task, sw_tag, task->itt, sess->age, tag, *hdr_itt);
+	return 0;
+}
+
+void cxgbi_parse_pdu_itt(struct iscsi_conn *conn, itt_t itt, int *idx, int *age)
+{
+	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+	struct cxgbi_conn *cconn = tcp_conn->dd_data;
+	struct cxgbi_device *cdev = cconn->chba->cdev;
+	struct cxgbi_ppm *ppm = cdev->cdev2ppm(cdev);
+	u32 tag = ntohl((__force u32)itt);
+	u32 sw_bits;
+
+	if (ppm) {
+		if (cxgbi_ppm_is_ddp_tag(ppm, tag))
+			sw_bits = cxgbi_ppm_get_tag_caller_data(ppm, tag);
+		else
+			sw_bits = cxgbi_ppm_decode_non_ddp_tag(ppm, tag);
+	} else {
+		sw_bits = tag;
+	}
+
+	cxgbi_decode_sw_tag(sw_bits, idx, age);
+	log_debug(1 << CXGBI_DBG_DDP,
+		  "cdev 0x%p, tag 0x%x/0x%x, -> 0x%x(0x%x,0x%x).\n",
+		  cdev, tag, itt, sw_bits, idx ? *idx : 0xFFFFF,
+		  age ? *age : 0xFF);
+}
+EXPORT_SYMBOL_GPL(cxgbi_parse_pdu_itt);
+
+void cxgbi_conn_tx_open(struct cxgbi_sock *csk)
+{
+	struct iscsi_conn *conn = csk->user_data;
+
+	if (conn) {
+		log_debug(1 << CXGBI_DBG_SOCK,
+			"csk 0x%p, cid %d.\n", csk, conn->id);
+		iscsi_conn_queue_work(conn);
+	}
+}
+EXPORT_SYMBOL_GPL(cxgbi_conn_tx_open);
+
+/*
+ * pdu receive, interact with libiscsi_tcp
+ */
+static inline int read_pdu_skb(struct iscsi_conn *conn,
+			       struct sk_buff *skb,
+			       unsigned int offset,
+			       int offloaded)
+{
+	int status = 0;
+	int bytes_read;
+
+	bytes_read = iscsi_tcp_recv_skb(conn, skb, offset, offloaded, &status);
+	switch (status) {
+	case ISCSI_TCP_CONN_ERR:
+		pr_info("skb 0x%p, off %u, %d, TCP_ERR.\n",
+			  skb, offset, offloaded);
+		return -EIO;
+	case ISCSI_TCP_SUSPENDED:
+		log_debug(1 << CXGBI_DBG_PDU_RX,
+			"skb 0x%p, off %u, %d, TCP_SUSPEND, rc %d.\n",
+			skb, offset, offloaded, bytes_read);
+		/* no transfer - just have caller flush queue */
+		return bytes_read;
+	case ISCSI_TCP_SKB_DONE:
+		pr_info("skb 0x%p, off %u, %d, TCP_SKB_DONE.\n",
+			skb, offset, offloaded);
+		/*
+		 * pdus should always fit in the skb and we should get
+		 * segment done notifcation.
+		 */
+		iscsi_conn_printk(KERN_ERR, conn, "Invalid pdu or skb.");
+		return -EFAULT;
+	case ISCSI_TCP_SEGMENT_DONE:
+		log_debug(1 << CXGBI_DBG_PDU_RX,
+			"skb 0x%p, off %u, %d, TCP_SEG_DONE, rc %d.\n",
+			skb, offset, offloaded, bytes_read);
+		return bytes_read;
+	default:
+		pr_info("skb 0x%p, off %u, %d, invalid status %d.\n",
+			skb, offset, offloaded, status);
+		return -EINVAL;
+	}
+}
+
+static int
+skb_read_pdu_bhs(struct cxgbi_sock *csk, struct iscsi_conn *conn,
+		 struct sk_buff *skb)
+{
+	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+	int err;
+
+	log_debug(1 << CXGBI_DBG_PDU_RX,
+		"conn 0x%p, skb 0x%p, len %u, flag 0x%lx.\n",
+		conn, skb, skb->len, cxgbi_skcb_flags(skb));
+
+	if (!iscsi_tcp_recv_segment_is_hdr(tcp_conn)) {
+		pr_info("conn 0x%p, skb 0x%p, not hdr.\n", conn, skb);
+		iscsi_conn_failure(conn, ISCSI_ERR_PROTO);
+		return -EIO;
+	}
+
+	if (conn->hdrdgst_en &&
+	    cxgbi_skcb_test_flag(skb, SKCBF_RX_HCRC_ERR)) {
+		pr_info("conn 0x%p, skb 0x%p, hcrc.\n", conn, skb);
+		iscsi_conn_failure(conn, ISCSI_ERR_HDR_DGST);
+		return -EIO;
+	}
+
+	if (cxgbi_skcb_test_flag(skb, SKCBF_RX_ISCSI_COMPL) &&
+	    cxgbi_skcb_test_flag(skb, SKCBF_RX_DATA_DDPD)) {
+		/* If completion flag is set and data is directly
+		 * placed in to the host memory then update
+		 * task->exp_datasn to the datasn in completion
+		 * iSCSI hdr as T6 adapter generates completion only
+		 * for the last pdu of a sequence.
+		 */
+		itt_t itt = ((struct iscsi_data *)skb->data)->itt;
+		struct iscsi_task *task = iscsi_itt_to_ctask(conn, itt);
+		u32 data_sn = be32_to_cpu(((struct iscsi_data *)
+							skb->data)->datasn);
+		if (task && task->sc) {
+			struct iscsi_tcp_task *tcp_task = task->dd_data;
+
+			tcp_task->exp_datasn = data_sn;
+		}
+	}
+
+	err = read_pdu_skb(conn, skb, 0, 0);
+	if (likely(err >= 0)) {
+		struct iscsi_hdr *hdr = (struct iscsi_hdr *)skb->data;
+		u8 opcode = hdr->opcode & ISCSI_OPCODE_MASK;
+
+		if (unlikely(opcode == ISCSI_OP_LOGOUT_RSP))
+			cxgbi_sock_set_flag(csk, CTPF_LOGOUT_RSP_RCVD);
+	}
+
+	return err;
+}
+
+static int skb_read_pdu_data(struct iscsi_conn *conn, struct sk_buff *lskb,
+			     struct sk_buff *skb, unsigned int offset)
+{
+	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+	bool offloaded = 0;
+	int opcode = tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK;
+
+	log_debug(1 << CXGBI_DBG_PDU_RX,
+		"conn 0x%p, skb 0x%p, len %u, flag 0x%lx.\n",
+		conn, skb, skb->len, cxgbi_skcb_flags(skb));
+
+	if (conn->datadgst_en &&
+	    cxgbi_skcb_test_flag(lskb, SKCBF_RX_DCRC_ERR)) {
+		pr_info("conn 0x%p, skb 0x%p, dcrc 0x%lx.\n",
+			conn, lskb, cxgbi_skcb_flags(lskb));
+		iscsi_conn_failure(conn, ISCSI_ERR_DATA_DGST);
+		return -EIO;
+	}
+
+	if (iscsi_tcp_recv_segment_is_hdr(tcp_conn))
+		return 0;
+
+	/* coalesced, add header digest length */
+	if (lskb == skb && conn->hdrdgst_en)
+		offset += ISCSI_DIGEST_SIZE;
+
+	if (cxgbi_skcb_test_flag(lskb, SKCBF_RX_DATA_DDPD))
+		offloaded = 1;
+
+	if (opcode == ISCSI_OP_SCSI_DATA_IN)
+		log_debug(1 << CXGBI_DBG_PDU_RX,
+			"skb 0x%p, op 0x%x, itt 0x%x, %u %s ddp'ed.\n",
+			skb, opcode, ntohl(tcp_conn->in.hdr->itt),
+			tcp_conn->in.datalen, offloaded ? "is" : "not");
+
+	return read_pdu_skb(conn, skb, offset, offloaded);
+}
+
+static void csk_return_rx_credits(struct cxgbi_sock *csk, int copied)
+{
+	struct cxgbi_device *cdev = csk->cdev;
+	int must_send;
+	u32 credits;
+
+	log_debug(1 << CXGBI_DBG_PDU_RX,
+		"csk 0x%p,%u,0x%lx,%u, seq %u, wup %u, thre %u, %u.\n",
+		csk, csk->state, csk->flags, csk->tid, csk->copied_seq,
+		csk->rcv_wup, cdev->rx_credit_thres,
+		csk->rcv_win);
+
+	if (!cdev->rx_credit_thres)
+		return;
+
+	if (csk->state != CTP_ESTABLISHED)
+		return;
+
+	credits = csk->copied_seq - csk->rcv_wup;
+	if (unlikely(!credits))
+		return;
+	must_send = credits + 16384 >= csk->rcv_win;
+	if (must_send || credits >= cdev->rx_credit_thres)
+		csk->rcv_wup += cdev->csk_send_rx_credits(csk, credits);
+}
+
+void cxgbi_conn_pdu_ready(struct cxgbi_sock *csk)
+{
+	struct cxgbi_device *cdev = csk->cdev;
+	struct iscsi_conn *conn = csk->user_data;
+	struct sk_buff *skb;
+	unsigned int read = 0;
+	int err = 0;
+
+	log_debug(1 << CXGBI_DBG_PDU_RX,
+		"csk 0x%p, conn 0x%p.\n", csk, conn);
+
+	if (unlikely(!conn || conn->suspend_rx)) {
+		log_debug(1 << CXGBI_DBG_PDU_RX,
+			"csk 0x%p, conn 0x%p, id %d, suspend_rx %lu!\n",
+			csk, conn, conn ? conn->id : 0xFF,
+			conn ? conn->suspend_rx : 0xFF);
+		return;
+	}
+
+	while (!err) {
+		skb = skb_peek(&csk->receive_queue);
+		if (!skb ||
+		    !(cxgbi_skcb_test_flag(skb, SKCBF_RX_STATUS))) {
+			if (skb)
+				log_debug(1 << CXGBI_DBG_PDU_RX,
+					"skb 0x%p, NOT ready 0x%lx.\n",
+					skb, cxgbi_skcb_flags(skb));
+			break;
+		}
+		__skb_unlink(skb, &csk->receive_queue);
+
+		read += cxgbi_skcb_rx_pdulen(skb);
+		log_debug(1 << CXGBI_DBG_PDU_RX,
+			"csk 0x%p, skb 0x%p,%u,f 0x%lx, pdu len %u.\n",
+			csk, skb, skb->len, cxgbi_skcb_flags(skb),
+			cxgbi_skcb_rx_pdulen(skb));
+
+		if (cxgbi_skcb_test_flag(skb, SKCBF_RX_COALESCED)) {
+			err = skb_read_pdu_bhs(csk, conn, skb);
+			if (err < 0) {
+				pr_err("coalesced bhs, csk 0x%p, skb 0x%p,%u, "
+					"f 0x%lx, plen %u.\n",
+					csk, skb, skb->len,
+					cxgbi_skcb_flags(skb),
+					cxgbi_skcb_rx_pdulen(skb));
+				goto skb_done;
+			}
+			err = skb_read_pdu_data(conn, skb, skb,
+						err + cdev->skb_rx_extra);
+			if (err < 0)
+				pr_err("coalesced data, csk 0x%p, skb 0x%p,%u, "
+					"f 0x%lx, plen %u.\n",
+					csk, skb, skb->len,
+					cxgbi_skcb_flags(skb),
+					cxgbi_skcb_rx_pdulen(skb));
+		} else {
+			err = skb_read_pdu_bhs(csk, conn, skb);
+			if (err < 0) {
+				pr_err("bhs, csk 0x%p, skb 0x%p,%u, "
+					"f 0x%lx, plen %u.\n",
+					csk, skb, skb->len,
+					cxgbi_skcb_flags(skb),
+					cxgbi_skcb_rx_pdulen(skb));
+				goto skb_done;
+			}
+
+			if (cxgbi_skcb_test_flag(skb, SKCBF_RX_DATA)) {
+				struct sk_buff *dskb;
+
+				dskb = skb_peek(&csk->receive_queue);
+				if (!dskb) {
+					pr_err("csk 0x%p, skb 0x%p,%u, f 0x%lx,"
+						" plen %u, NO data.\n",
+						csk, skb, skb->len,
+						cxgbi_skcb_flags(skb),
+						cxgbi_skcb_rx_pdulen(skb));
+					err = -EIO;
+					goto skb_done;
+				}
+				__skb_unlink(dskb, &csk->receive_queue);
+
+				err = skb_read_pdu_data(conn, skb, dskb, 0);
+				if (err < 0)
+					pr_err("data, csk 0x%p, skb 0x%p,%u, "
+						"f 0x%lx, plen %u, dskb 0x%p,"
+						"%u.\n",
+						csk, skb, skb->len,
+						cxgbi_skcb_flags(skb),
+						cxgbi_skcb_rx_pdulen(skb),
+						dskb, dskb->len);
+				__kfree_skb(dskb);
+			} else
+				err = skb_read_pdu_data(conn, skb, skb, 0);
+		}
+skb_done:
+		__kfree_skb(skb);
+
+		if (err < 0)
+			break;
+	}
+
+	log_debug(1 << CXGBI_DBG_PDU_RX, "csk 0x%p, read %u.\n", csk, read);
+	if (read) {
+		csk->copied_seq += read;
+		csk_return_rx_credits(csk, read);
+		conn->rxdata_octets += read;
+	}
+
+	if (err < 0) {
+		pr_info("csk 0x%p, 0x%p, rx failed %d, read %u.\n",
+			csk, conn, err, read);
+		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+	}
+}
+EXPORT_SYMBOL_GPL(cxgbi_conn_pdu_ready);
+
+static int sgl_seek_offset(struct scatterlist *sgl, unsigned int sgcnt,
+				unsigned int offset, unsigned int *off,
+				struct scatterlist **sgp)
+{
+	int i;
+	struct scatterlist *sg;
+
+	for_each_sg(sgl, sg, sgcnt, i) {
+		if (offset < sg->length) {
+			*off = offset;
+			*sgp = sg;
+			return 0;
+		}
+		offset -= sg->length;
+	}
+	return -EFAULT;
+}
+
+static int sgl_read_to_frags(struct scatterlist *sg, unsigned int sgoffset,
+				unsigned int dlen, struct page_frag *frags,
+				int frag_max)
+{
+	unsigned int datalen = dlen;
+	unsigned int sglen = sg->length - sgoffset;
+	struct page *page = sg_page(sg);
+	int i;
+
+	i = 0;
+	do {
+		unsigned int copy;
+
+		if (!sglen) {
+			sg = sg_next(sg);
+			if (!sg) {
+				pr_warn("sg %d NULL, len %u/%u.\n",
+					i, datalen, dlen);
+				return -EINVAL;
+			}
+			sgoffset = 0;
+			sglen = sg->length;
+			page = sg_page(sg);
+
+		}
+		copy = min(datalen, sglen);
+		if (i && page == frags[i - 1].page &&
+		    sgoffset + sg->offset ==
+			frags[i - 1].offset + frags[i - 1].size) {
+			frags[i - 1].size += copy;
+		} else {
+			if (i >= frag_max) {
+				pr_warn("too many pages %u, dlen %u.\n",
+					frag_max, dlen);
+				return -EINVAL;
+			}
+
+			frags[i].page = page;
+			frags[i].offset = sg->offset + sgoffset;
+			frags[i].size = copy;
+			i++;
+		}
+		datalen -= copy;
+		sgoffset += copy;
+		sglen -= copy;
+	} while (datalen);
+
+	return i;
+}
+
+int cxgbi_conn_alloc_pdu(struct iscsi_task *task, u8 opcode)
+{
+	struct iscsi_tcp_conn *tcp_conn = task->conn->dd_data;
+	struct cxgbi_conn *cconn = tcp_conn->dd_data;
+	struct cxgbi_device *cdev = cconn->chba->cdev;
+	struct iscsi_conn *conn = task->conn;
+	struct iscsi_tcp_task *tcp_task = task->dd_data;
+	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
+	struct scsi_cmnd *sc = task->sc;
+	struct cxgbi_sock *csk = cconn->cep->csk;
+	struct net_device *ndev = cdev->ports[csk->port_id];
+	int headroom = SKB_TX_ISCSI_PDU_HEADER_MAX;
+
+	tcp_task->dd_data = tdata;
+	task->hdr = NULL;
+
+	if (SKB_MAX_HEAD(cdev->skb_tx_rsvd) > (512 * MAX_SKB_FRAGS) &&
+	    (opcode == ISCSI_OP_SCSI_DATA_OUT ||
+	     (opcode == ISCSI_OP_SCSI_CMD &&
+	      (scsi_bidi_cmnd(sc) || sc->sc_data_direction == DMA_TO_DEVICE))))
+		/* data could goes into skb head */
+		headroom += min_t(unsigned int,
+				SKB_MAX_HEAD(cdev->skb_tx_rsvd),
+				conn->max_xmit_dlength);
+
+	tdata->skb = alloc_skb(cdev->skb_tx_rsvd + headroom, GFP_ATOMIC);
+	if (!tdata->skb) {
+		ndev->stats.tx_dropped++;
+		return -ENOMEM;
+	}
+
+	skb_reserve(tdata->skb, cdev->skb_tx_rsvd);
+
+	if (task->sc) {
+		task->hdr = (struct iscsi_hdr *)tdata->skb->data;
+	} else {
+		task->hdr = kzalloc(SKB_TX_ISCSI_PDU_HEADER_MAX, GFP_ATOMIC);
+		if (!task->hdr) {
+			__kfree_skb(tdata->skb);
+			tdata->skb = NULL;
+			ndev->stats.tx_dropped++;
+			return -ENOMEM;
+		}
+	}
+	task->hdr_max = SKB_TX_ISCSI_PDU_HEADER_MAX; /* BHS + AHS */
+
+	/* data_out uses scsi_cmd's itt */
+	if (opcode != ISCSI_OP_SCSI_DATA_OUT)
+		task_reserve_itt(task, &task->hdr->itt);
+
+	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
+		"task 0x%p, op 0x%x, skb 0x%p,%u+%u/%u, itt 0x%x.\n",
+		task, opcode, tdata->skb, cdev->skb_tx_rsvd, headroom,
+		conn->max_xmit_dlength, ntohl(task->hdr->itt));
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cxgbi_conn_alloc_pdu);
+
+static inline void tx_skb_setmode(struct sk_buff *skb, int hcrc, int dcrc)
+{
+	if (hcrc || dcrc) {
+		u8 submode = 0;
+
+		if (hcrc)
+			submode |= 1;
+		if (dcrc)
+			submode |= 2;
+		cxgbi_skcb_ulp_mode(skb) = (ULP2_MODE_ISCSI << 4) | submode;
+	} else
+		cxgbi_skcb_ulp_mode(skb) = 0;
+}
+
+int cxgbi_conn_init_pdu(struct iscsi_task *task, unsigned int offset,
+			      unsigned int count)
+{
+	struct iscsi_conn *conn = task->conn;
+	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
+	struct sk_buff *skb = tdata->skb;
+	unsigned int datalen = count;
+	int i, padlen = iscsi_padding(count);
+	struct page *pg;
+
+	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
+		"task 0x%p,0x%p, skb 0x%p, 0x%x,0x%x,0x%x, %u+%u.\n",
+		task, task->sc, skb, (*skb->data) & ISCSI_OPCODE_MASK,
+		ntohl(task->cmdsn), ntohl(task->hdr->itt), offset, count);
+
+	skb_put(skb, task->hdr_len);
+	tx_skb_setmode(skb, conn->hdrdgst_en, datalen ? conn->datadgst_en : 0);
+	if (!count)
+		return 0;
+
+	if (task->sc) {
+		struct scsi_data_buffer *sdb = scsi_out(task->sc);
+		struct scatterlist *sg = NULL;
+		int err;
+
+		tdata->offset = offset;
+		tdata->count = count;
+		err = sgl_seek_offset(
+					sdb->table.sgl, sdb->table.nents,
+					tdata->offset, &tdata->sgoffset, &sg);
+		if (err < 0) {
+			pr_warn("tpdu, sgl %u, bad offset %u/%u.\n",
+				sdb->table.nents, tdata->offset, sdb->length);
+			return err;
+		}
+		err = sgl_read_to_frags(sg, tdata->sgoffset, tdata->count,
+					tdata->frags, MAX_PDU_FRAGS);
+		if (err < 0) {
+			pr_warn("tpdu, sgl %u, bad offset %u + %u.\n",
+				sdb->table.nents, tdata->offset, tdata->count);
+			return err;
+		}
+		tdata->nr_frags = err;
+
+		if (tdata->nr_frags > MAX_SKB_FRAGS ||
+		    (padlen && tdata->nr_frags == MAX_SKB_FRAGS)) {
+			char *dst = skb->data + task->hdr_len;
+			struct page_frag *frag = tdata->frags;
+
+			/* data fits in the skb's headroom */
+			for (i = 0; i < tdata->nr_frags; i++, frag++) {
+				char *src = kmap_atomic(frag->page);
+
+				memcpy(dst, src+frag->offset, frag->size);
+				dst += frag->size;
+				kunmap_atomic(src);
+			}
+			if (padlen) {
+				memset(dst, 0, padlen);
+				padlen = 0;
+			}
+			skb_put(skb, count + padlen);
+		} else {
+			/* data fit into frag_list */
+			for (i = 0; i < tdata->nr_frags; i++) {
+				__skb_fill_page_desc(skb, i,
+						tdata->frags[i].page,
+						tdata->frags[i].offset,
+						tdata->frags[i].size);
+				skb_frag_ref(skb, i);
+			}
+			skb_shinfo(skb)->nr_frags = tdata->nr_frags;
+			skb->len += count;
+			skb->data_len += count;
+			skb->truesize += count;
+		}
+
+	} else {
+		pg = virt_to_page(task->data);
+
+		get_page(pg);
+		skb_fill_page_desc(skb, 0, pg, offset_in_page(task->data),
+					count);
+		skb->len += count;
+		skb->data_len += count;
+		skb->truesize += count;
+	}
+
+	if (padlen) {
+		i = skb_shinfo(skb)->nr_frags;
+		skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
+				virt_to_page(padding), offset_in_page(padding),
+				padlen);
+
+		skb->data_len += padlen;
+		skb->truesize += padlen;
+		skb->len += padlen;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cxgbi_conn_init_pdu);
+
+int cxgbi_conn_xmit_pdu(struct iscsi_task *task)
+{
+	struct iscsi_tcp_conn *tcp_conn = task->conn->dd_data;
+	struct cxgbi_conn *cconn = tcp_conn->dd_data;
+	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
+	struct cxgbi_task_tag_info *ttinfo = &tdata->ttinfo;
+	struct sk_buff *skb = tdata->skb;
+	struct cxgbi_sock *csk = NULL;
+	unsigned int datalen;
+	int err;
+
+	if (!skb) {
+		log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
+			"task 0x%p\n", task);
+		return 0;
+	}
+
+	if (cconn && cconn->cep)
+		csk = cconn->cep->csk;
+	if (!csk) {
+		log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
+			  "task 0x%p, csk gone.\n", task);
+		return -EPIPE;
+	}
+
+	tdata->skb = NULL;
+	datalen = skb->data_len;
+
+	/* write ppod first if using ofldq to write ppod */
+	if (ttinfo->flags & CXGBI_PPOD_INFO_FLAG_VALID) {
+		struct cxgbi_ppm *ppm = csk->cdev->cdev2ppm(csk->cdev);
+
+		ttinfo->flags &= ~CXGBI_PPOD_INFO_FLAG_VALID;
+		if (csk->cdev->csk_ddp_set_map(ppm, csk, ttinfo) < 0)
+			pr_err("task 0x%p, ppod writing using ofldq failed.\n",
+			       task);
+			/* continue. Let fl get the data */
+	}
+
+	if (!task->sc)
+		memcpy(skb->data, task->hdr, SKB_TX_ISCSI_PDU_HEADER_MAX);
+
+	err = cxgbi_sock_send_pdus(cconn->cep->csk, skb);
+	if (err > 0) {
+		int pdulen = err;
+
+		log_debug(1 << CXGBI_DBG_PDU_TX,
+			"task 0x%p,0x%p, skb 0x%p, len %u/%u, rv %d.\n",
+			task, task->sc, skb, skb->len, skb->data_len, err);
+
+		if (task->conn->hdrdgst_en)
+			pdulen += ISCSI_DIGEST_SIZE;
+
+		if (datalen && task->conn->datadgst_en)
+			pdulen += ISCSI_DIGEST_SIZE;
+
+		task->conn->txdata_octets += pdulen;
+		return 0;
+	}
+
+	if (err == -EAGAIN || err == -ENOBUFS) {
+		log_debug(1 << CXGBI_DBG_PDU_TX,
+			"task 0x%p, skb 0x%p, len %u/%u, %d EAGAIN.\n",
+			task, skb, skb->len, skb->data_len, err);
+		/* reset skb to send when we are called again */
+		tdata->skb = skb;
+		return err;
+	}
+
+	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
+		"itt 0x%x, skb 0x%p, len %u/%u, xmit err %d.\n",
+		task->itt, skb, skb->len, skb->data_len, err);
+
+	__kfree_skb(skb);
+
+	iscsi_conn_printk(KERN_ERR, task->conn, "xmit err %d.\n", err);
+	iscsi_conn_failure(task->conn, ISCSI_ERR_XMIT_FAILED);
+	return err;
+}
+EXPORT_SYMBOL_GPL(cxgbi_conn_xmit_pdu);
+
+void cxgbi_cleanup_task(struct iscsi_task *task)
+{
+	struct iscsi_tcp_task *tcp_task = task->dd_data;
+	struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
+
+	if (!tcp_task || !tdata || (tcp_task->dd_data != tdata)) {
+		pr_info("task 0x%p,0x%p, tcp_task 0x%p, tdata 0x%p/0x%p.\n",
+			task, task->sc, tcp_task,
+			tcp_task ? tcp_task->dd_data : NULL, tdata);
+		return;
+	}
+
+	log_debug(1 << CXGBI_DBG_ISCSI,
+		"task 0x%p, skb 0x%p, itt 0x%x.\n",
+		task, tdata->skb, task->hdr_itt);
+
+	tcp_task->dd_data = NULL;
+
+	if (!task->sc)
+		kfree(task->hdr);
+	task->hdr = NULL;
+
+	/*  never reached the xmit task callout */
+	if (tdata->skb) {
+		__kfree_skb(tdata->skb);
+		tdata->skb = NULL;
+	}
+
+	task_release_itt(task, task->hdr_itt);
+	memset(tdata, 0, sizeof(*tdata));
+
+	iscsi_tcp_cleanup_task(task);
+}
+EXPORT_SYMBOL_GPL(cxgbi_cleanup_task);
+
+void cxgbi_get_conn_stats(struct iscsi_cls_conn *cls_conn,
+				struct iscsi_stats *stats)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+
+	stats->txdata_octets = conn->txdata_octets;
+	stats->rxdata_octets = conn->rxdata_octets;
+	stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
+	stats->dataout_pdus = conn->dataout_pdus_cnt;
+	stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
+	stats->datain_pdus = conn->datain_pdus_cnt;
+	stats->r2t_pdus = conn->r2t_pdus_cnt;
+	stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
+	stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
+	stats->digest_err = 0;
+	stats->timeout_err = 0;
+	stats->custom_length = 1;
+	strcpy(stats->custom[0].desc, "eh_abort_cnt");
+	stats->custom[0].value = conn->eh_abort_cnt;
+}
+EXPORT_SYMBOL_GPL(cxgbi_get_conn_stats);
+
+static int cxgbi_conn_max_xmit_dlength(struct iscsi_conn *conn)
+{
+	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+	struct cxgbi_conn *cconn = tcp_conn->dd_data;
+	struct cxgbi_device *cdev = cconn->chba->cdev;
+	unsigned int headroom = SKB_MAX_HEAD(cdev->skb_tx_rsvd);
+	unsigned int max_def = 512 * MAX_SKB_FRAGS;
+	unsigned int max = max(max_def, headroom);
+
+	max = min(cconn->chba->cdev->tx_max_size, max);
+	if (conn->max_xmit_dlength)
+		conn->max_xmit_dlength = min(conn->max_xmit_dlength, max);
+	else
+		conn->max_xmit_dlength = max;
+	cxgbi_align_pdu_size(conn->max_xmit_dlength);
+
+	return 0;
+}
+
+static int cxgbi_conn_max_recv_dlength(struct iscsi_conn *conn)
+{
+	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+	struct cxgbi_conn *cconn = tcp_conn->dd_data;
+	unsigned int max = cconn->chba->cdev->rx_max_size;
+
+	cxgbi_align_pdu_size(max);
+
+	if (conn->max_recv_dlength) {
+		if (conn->max_recv_dlength > max) {
+			pr_err("MaxRecvDataSegmentLength %u > %u.\n",
+				conn->max_recv_dlength, max);
+			return -EINVAL;
+		}
+		conn->max_recv_dlength = min(conn->max_recv_dlength, max);
+		cxgbi_align_pdu_size(conn->max_recv_dlength);
+	} else
+		conn->max_recv_dlength = max;
+
+	return 0;
+}
+
+int cxgbi_set_conn_param(struct iscsi_cls_conn *cls_conn,
+			enum iscsi_param param, char *buf, int buflen)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+	struct cxgbi_conn *cconn = tcp_conn->dd_data;
+	struct cxgbi_sock *csk = cconn->cep->csk;
+	int err;
+
+	log_debug(1 << CXGBI_DBG_ISCSI,
+		"cls_conn 0x%p, param %d, buf(%d) %s.\n",
+		cls_conn, param, buflen, buf);
+
+	switch (param) {
+	case ISCSI_PARAM_HDRDGST_EN:
+		err = iscsi_set_param(cls_conn, param, buf, buflen);
+		if (!err && conn->hdrdgst_en)
+			err = csk->cdev->csk_ddp_setup_digest(csk, csk->tid,
+							conn->hdrdgst_en,
+							conn->datadgst_en);
+		break;
+	case ISCSI_PARAM_DATADGST_EN:
+		err = iscsi_set_param(cls_conn, param, buf, buflen);
+		if (!err && conn->datadgst_en)
+			err = csk->cdev->csk_ddp_setup_digest(csk, csk->tid,
+							conn->hdrdgst_en,
+							conn->datadgst_en);
+		break;
+	case ISCSI_PARAM_MAX_R2T:
+		return iscsi_tcp_set_max_r2t(conn, buf);
+	case ISCSI_PARAM_MAX_RECV_DLENGTH:
+		err = iscsi_set_param(cls_conn, param, buf, buflen);
+		if (!err)
+			err = cxgbi_conn_max_recv_dlength(conn);
+		break;
+	case ISCSI_PARAM_MAX_XMIT_DLENGTH:
+		err = iscsi_set_param(cls_conn, param, buf, buflen);
+		if (!err)
+			err = cxgbi_conn_max_xmit_dlength(conn);
+		break;
+	default:
+		return iscsi_set_param(cls_conn, param, buf, buflen);
+	}
+	return err;
+}
+EXPORT_SYMBOL_GPL(cxgbi_set_conn_param);
+
+static inline int csk_print_port(struct cxgbi_sock *csk, char *buf)
+{
+	int len;
+
+	cxgbi_sock_get(csk);
+	len = sprintf(buf, "%hu\n", ntohs(csk->daddr.sin_port));
+	cxgbi_sock_put(csk);
+
+	return len;
+}
+
+static inline int csk_print_ip(struct cxgbi_sock *csk, char *buf)
+{
+	int len;
+
+	cxgbi_sock_get(csk);
+	if (csk->csk_family == AF_INET)
+		len = sprintf(buf, "%pI4",
+			      &csk->daddr.sin_addr.s_addr);
+	else
+		len = sprintf(buf, "%pI6",
+			      &csk->daddr6.sin6_addr);
+
+	cxgbi_sock_put(csk);
+
+	return len;
+}
+
+int cxgbi_get_ep_param(struct iscsi_endpoint *ep, enum iscsi_param param,
+		       char *buf)
+{
+	struct cxgbi_endpoint *cep = ep->dd_data;
+	struct cxgbi_sock *csk;
+	int len;
+
+	log_debug(1 << CXGBI_DBG_ISCSI,
+		"cls_conn 0x%p, param %d.\n", ep, param);
+
+	switch (param) {
+	case ISCSI_PARAM_CONN_PORT:
+	case ISCSI_PARAM_CONN_ADDRESS:
+		if (!cep)
+			return -ENOTCONN;
+
+		csk = cep->csk;
+		if (!csk)
+			return -ENOTCONN;
+
+		return iscsi_conn_get_addr_param((struct sockaddr_storage *)
+						 &csk->daddr, param, buf);
+	default:
+		return -ENOSYS;
+	}
+	return len;
+}
+EXPORT_SYMBOL_GPL(cxgbi_get_ep_param);
+
+struct iscsi_cls_conn *
+cxgbi_create_conn(struct iscsi_cls_session *cls_session, u32 cid)
+{
+	struct iscsi_cls_conn *cls_conn;
+	struct iscsi_conn *conn;
+	struct iscsi_tcp_conn *tcp_conn;
+	struct cxgbi_conn *cconn;
+
+	cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*cconn), cid);
+	if (!cls_conn)
+		return NULL;
+
+	conn = cls_conn->dd_data;
+	tcp_conn = conn->dd_data;
+	cconn = tcp_conn->dd_data;
+	cconn->iconn = conn;
+
+	log_debug(1 << CXGBI_DBG_ISCSI,
+		"cid %u(0x%x), cls 0x%p,0x%p, conn 0x%p,0x%p,0x%p.\n",
+		cid, cid, cls_session, cls_conn, conn, tcp_conn, cconn);
+
+	return cls_conn;
+}
+EXPORT_SYMBOL_GPL(cxgbi_create_conn);
+
+int cxgbi_bind_conn(struct iscsi_cls_session *cls_session,
+				struct iscsi_cls_conn *cls_conn,
+				u64 transport_eph, int is_leading)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+	struct cxgbi_conn *cconn = tcp_conn->dd_data;
+	struct cxgbi_ppm *ppm;
+	struct iscsi_endpoint *ep;
+	struct cxgbi_endpoint *cep;
+	struct cxgbi_sock *csk;
+	int err;
+
+	ep = iscsi_lookup_endpoint(transport_eph);
+	if (!ep)
+		return -EINVAL;
+
+	/*  setup ddp pagesize */
+	cep = ep->dd_data;
+	csk = cep->csk;
+
+	ppm = csk->cdev->cdev2ppm(csk->cdev);
+	err = csk->cdev->csk_ddp_setup_pgidx(csk, csk->tid,
+					     ppm->tformat.pgsz_idx_dflt);
+	if (err < 0)
+		return err;
+
+	err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
+	if (err)
+		return -EINVAL;
+
+	/*  calculate the tag idx bits needed for this conn based on cmds_max */
+	cconn->task_idx_bits = (__ilog2_u32(conn->session->cmds_max - 1)) + 1;
+
+	write_lock_bh(&csk->callback_lock);
+	csk->user_data = conn;
+	cconn->chba = cep->chba;
+	cconn->cep = cep;
+	cep->cconn = cconn;
+	write_unlock_bh(&csk->callback_lock);
+
+	cxgbi_conn_max_xmit_dlength(conn);
+	cxgbi_conn_max_recv_dlength(conn);
+
+	log_debug(1 << CXGBI_DBG_ISCSI,
+		"cls 0x%p,0x%p, ep 0x%p, cconn 0x%p, csk 0x%p.\n",
+		cls_session, cls_conn, ep, cconn, csk);
+	/*  init recv engine */
+	iscsi_tcp_hdr_recv_prep(tcp_conn);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cxgbi_bind_conn);
+
+struct iscsi_cls_session *cxgbi_create_session(struct iscsi_endpoint *ep,
+						u16 cmds_max, u16 qdepth,
+						u32 initial_cmdsn)
+{
+	struct cxgbi_endpoint *cep;
+	struct cxgbi_hba *chba;
+	struct Scsi_Host *shost;
+	struct iscsi_cls_session *cls_session;
+	struct iscsi_session *session;
+
+	if (!ep) {
+		pr_err("missing endpoint.\n");
+		return NULL;
+	}
+
+	cep = ep->dd_data;
+	chba = cep->chba;
+	shost = chba->shost;
+
+	BUG_ON(chba != iscsi_host_priv(shost));
+
+	cls_session = iscsi_session_setup(chba->cdev->itp, shost,
+					cmds_max, 0,
+					sizeof(struct iscsi_tcp_task) +
+					sizeof(struct cxgbi_task_data),
+					initial_cmdsn, ISCSI_MAX_TARGET);
+	if (!cls_session)
+		return NULL;
+
+	session = cls_session->dd_data;
+	if (iscsi_tcp_r2tpool_alloc(session))
+		goto remove_session;
+
+	log_debug(1 << CXGBI_DBG_ISCSI,
+		"ep 0x%p, cls sess 0x%p.\n", ep, cls_session);
+	return cls_session;
+
+remove_session:
+	iscsi_session_teardown(cls_session);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(cxgbi_create_session);
+
+void cxgbi_destroy_session(struct iscsi_cls_session *cls_session)
+{
+	log_debug(1 << CXGBI_DBG_ISCSI,
+		"cls sess 0x%p.\n", cls_session);
+
+	iscsi_tcp_r2tpool_free(cls_session->dd_data);
+	iscsi_session_teardown(cls_session);
+}
+EXPORT_SYMBOL_GPL(cxgbi_destroy_session);
+
+int cxgbi_set_host_param(struct Scsi_Host *shost, enum iscsi_host_param param,
+			char *buf, int buflen)
+{
+	struct cxgbi_hba *chba = iscsi_host_priv(shost);
+
+	if (!chba->ndev) {
+		shost_printk(KERN_ERR, shost, "Could not get host param. "
+				"netdev for host not set.\n");
+		return -ENODEV;
+	}
+
+	log_debug(1 << CXGBI_DBG_ISCSI,
+		"shost 0x%p, hba 0x%p,%s, param %d, buf(%d) %s.\n",
+		shost, chba, chba->ndev->name, param, buflen, buf);
+
+	switch (param) {
+	case ISCSI_HOST_PARAM_IPADDRESS:
+	{
+		__be32 addr = in_aton(buf);
+		log_debug(1 << CXGBI_DBG_ISCSI,
+			"hba %s, req. ipv4 %pI4.\n", chba->ndev->name, &addr);
+		cxgbi_set_iscsi_ipv4(chba, addr);
+		return 0;
+	}
+	case ISCSI_HOST_PARAM_HWADDRESS:
+	case ISCSI_HOST_PARAM_NETDEV_NAME:
+		return 0;
+	default:
+		return iscsi_host_set_param(shost, param, buf, buflen);
+	}
+}
+EXPORT_SYMBOL_GPL(cxgbi_set_host_param);
+
+int cxgbi_get_host_param(struct Scsi_Host *shost, enum iscsi_host_param param,
+			char *buf)
+{
+	struct cxgbi_hba *chba = iscsi_host_priv(shost);
+	int len = 0;
+
+	if (!chba->ndev) {
+		shost_printk(KERN_ERR, shost, "Could not get host param. "
+				"netdev for host not set.\n");
+		return -ENODEV;
+	}
+
+	log_debug(1 << CXGBI_DBG_ISCSI,
+		"shost 0x%p, hba 0x%p,%s, param %d.\n",
+		shost, chba, chba->ndev->name, param);
+
+	switch (param) {
+	case ISCSI_HOST_PARAM_HWADDRESS:
+		len = sysfs_format_mac(buf, chba->ndev->dev_addr, 6);
+		break;
+	case ISCSI_HOST_PARAM_NETDEV_NAME:
+		len = sprintf(buf, "%s\n", chba->ndev->name);
+		break;
+	case ISCSI_HOST_PARAM_IPADDRESS:
+	{
+		struct cxgbi_sock *csk = find_sock_on_port(chba->cdev,
+							   chba->port_id);
+		if (csk) {
+			len = sprintf(buf, "%pIS",
+				      (struct sockaddr *)&csk->saddr);
+		}
+		log_debug(1 << CXGBI_DBG_ISCSI,
+			  "hba %s, addr %s.\n", chba->ndev->name, buf);
+		break;
+	}
+	default:
+		return iscsi_host_get_param(shost, param, buf);
+	}
+
+	return len;
+}
+EXPORT_SYMBOL_GPL(cxgbi_get_host_param);
+
+struct iscsi_endpoint *cxgbi_ep_connect(struct Scsi_Host *shost,
+					struct sockaddr *dst_addr,
+					int non_blocking)
+{
+	struct iscsi_endpoint *ep;
+	struct cxgbi_endpoint *cep;
+	struct cxgbi_hba *hba = NULL;
+	struct cxgbi_sock *csk;
+	int ifindex = 0;
+	int err = -EINVAL;
+
+	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_SOCK,
+		"shost 0x%p, non_blocking %d, dst_addr 0x%p.\n",
+		shost, non_blocking, dst_addr);
+
+	if (shost) {
+		hba = iscsi_host_priv(shost);
+		if (!hba) {
+			pr_info("shost 0x%p, priv NULL.\n", shost);
+			goto err_out;
+		}
+
+		rtnl_lock();
+		if (!vlan_uses_dev(hba->ndev))
+			ifindex = hba->ndev->ifindex;
+		rtnl_unlock();
+	}
+
+	if (dst_addr->sa_family == AF_INET) {
+		csk = cxgbi_check_route(dst_addr, ifindex);
+#if IS_ENABLED(CONFIG_IPV6)
+	} else if (dst_addr->sa_family == AF_INET6) {
+		csk = cxgbi_check_route6(dst_addr, ifindex);
+#endif
+	} else {
+		pr_info("address family 0x%x NOT supported.\n",
+			dst_addr->sa_family);
+		err = -EAFNOSUPPORT;
+		return (struct iscsi_endpoint *)ERR_PTR(err);
+	}
+
+	if (IS_ERR(csk))
+		return (struct iscsi_endpoint *)csk;
+	cxgbi_sock_get(csk);
+
+	if (!hba)
+		hba = csk->cdev->hbas[csk->port_id];
+	else if (hba != csk->cdev->hbas[csk->port_id]) {
+		pr_info("Could not connect through requested host %u"
+			"hba 0x%p != 0x%p (%u).\n",
+			shost->host_no, hba,
+			csk->cdev->hbas[csk->port_id], csk->port_id);
+		err = -ENOSPC;
+		goto release_conn;
+	}
+
+	err = sock_get_port(csk);
+	if (err)
+		goto release_conn;
+
+	cxgbi_sock_set_state(csk, CTP_CONNECTING);
+	err = csk->cdev->csk_init_act_open(csk);
+	if (err)
+		goto release_conn;
+
+	if (cxgbi_sock_is_closing(csk)) {
+		err = -ENOSPC;
+		pr_info("csk 0x%p is closing.\n", csk);
+		goto release_conn;
+	}
+
+	ep = iscsi_create_endpoint(sizeof(*cep));
+	if (!ep) {
+		err = -ENOMEM;
+		pr_info("iscsi alloc ep, OOM.\n");
+		goto release_conn;
+	}
+
+	cep = ep->dd_data;
+	cep->csk = csk;
+	cep->chba = hba;
+
+	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_SOCK,
+		"ep 0x%p, cep 0x%p, csk 0x%p, hba 0x%p,%s.\n",
+		ep, cep, csk, hba, hba->ndev->name);
+	return ep;
+
+release_conn:
+	cxgbi_sock_put(csk);
+	cxgbi_sock_closed(csk);
+err_out:
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(cxgbi_ep_connect);
+
+int cxgbi_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
+{
+	struct cxgbi_endpoint *cep = ep->dd_data;
+	struct cxgbi_sock *csk = cep->csk;
+
+	if (!cxgbi_sock_is_established(csk))
+		return 0;
+	return 1;
+}
+EXPORT_SYMBOL_GPL(cxgbi_ep_poll);
+
+void cxgbi_ep_disconnect(struct iscsi_endpoint *ep)
+{
+	struct cxgbi_endpoint *cep = ep->dd_data;
+	struct cxgbi_conn *cconn = cep->cconn;
+	struct cxgbi_sock *csk = cep->csk;
+
+	log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_SOCK,
+		"ep 0x%p, cep 0x%p, cconn 0x%p, csk 0x%p,%u,0x%lx.\n",
+		ep, cep, cconn, csk, csk->state, csk->flags);
+
+	if (cconn && cconn->iconn) {
+		iscsi_suspend_tx(cconn->iconn);
+		write_lock_bh(&csk->callback_lock);
+		cep->csk->user_data = NULL;
+		cconn->cep = NULL;
+		write_unlock_bh(&csk->callback_lock);
+	}
+	iscsi_destroy_endpoint(ep);
+
+	if (likely(csk->state >= CTP_ESTABLISHED))
+		need_active_close(csk);
+	else
+		cxgbi_sock_closed(csk);
+
+	cxgbi_sock_put(csk);
+}
+EXPORT_SYMBOL_GPL(cxgbi_ep_disconnect);
+
+int cxgbi_iscsi_init(struct iscsi_transport *itp,
+			struct scsi_transport_template **stt)
+{
+	*stt = iscsi_register_transport(itp);
+	if (*stt == NULL) {
+		pr_err("unable to register %s transport 0x%p.\n",
+			itp->name, itp);
+		return -ENODEV;
+	}
+	log_debug(1 << CXGBI_DBG_ISCSI,
+		"%s, registered iscsi transport 0x%p.\n",
+		itp->name, stt);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cxgbi_iscsi_init);
+
+void cxgbi_iscsi_cleanup(struct iscsi_transport *itp,
+			struct scsi_transport_template **stt)
+{
+	if (*stt) {
+		log_debug(1 << CXGBI_DBG_ISCSI,
+			"de-register transport 0x%p, %s, stt 0x%p.\n",
+			itp, itp->name, *stt);
+		*stt = NULL;
+		iscsi_unregister_transport(itp);
+	}
+}
+EXPORT_SYMBOL_GPL(cxgbi_iscsi_cleanup);
+
+umode_t cxgbi_attr_is_visible(int param_type, int param)
+{
+	switch (param_type) {
+	case ISCSI_HOST_PARAM:
+		switch (param) {
+		case ISCSI_HOST_PARAM_NETDEV_NAME:
+		case ISCSI_HOST_PARAM_HWADDRESS:
+		case ISCSI_HOST_PARAM_IPADDRESS:
+		case ISCSI_HOST_PARAM_INITIATOR_NAME:
+			return S_IRUGO;
+		default:
+			return 0;
+		}
+	case ISCSI_PARAM:
+		switch (param) {
+		case ISCSI_PARAM_MAX_RECV_DLENGTH:
+		case ISCSI_PARAM_MAX_XMIT_DLENGTH:
+		case ISCSI_PARAM_HDRDGST_EN:
+		case ISCSI_PARAM_DATADGST_EN:
+		case ISCSI_PARAM_CONN_ADDRESS:
+		case ISCSI_PARAM_CONN_PORT:
+		case ISCSI_PARAM_EXP_STATSN:
+		case ISCSI_PARAM_PERSISTENT_ADDRESS:
+		case ISCSI_PARAM_PERSISTENT_PORT:
+		case ISCSI_PARAM_PING_TMO:
+		case ISCSI_PARAM_RECV_TMO:
+		case ISCSI_PARAM_INITIAL_R2T_EN:
+		case ISCSI_PARAM_MAX_R2T:
+		case ISCSI_PARAM_IMM_DATA_EN:
+		case ISCSI_PARAM_FIRST_BURST:
+		case ISCSI_PARAM_MAX_BURST:
+		case ISCSI_PARAM_PDU_INORDER_EN:
+		case ISCSI_PARAM_DATASEQ_INORDER_EN:
+		case ISCSI_PARAM_ERL:
+		case ISCSI_PARAM_TARGET_NAME:
+		case ISCSI_PARAM_TPGT:
+		case ISCSI_PARAM_USERNAME:
+		case ISCSI_PARAM_PASSWORD:
+		case ISCSI_PARAM_USERNAME_IN:
+		case ISCSI_PARAM_PASSWORD_IN:
+		case ISCSI_PARAM_FAST_ABORT:
+		case ISCSI_PARAM_ABORT_TMO:
+		case ISCSI_PARAM_LU_RESET_TMO:
+		case ISCSI_PARAM_TGT_RESET_TMO:
+		case ISCSI_PARAM_IFACE_NAME:
+		case ISCSI_PARAM_INITIATOR_NAME:
+			return S_IRUGO;
+		default:
+			return 0;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cxgbi_attr_is_visible);
+
+static int __init libcxgbi_init_module(void)
+{
+	pr_info("%s", version);
+
+	BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, cb) <
+		     sizeof(struct cxgbi_skb_cb));
+	return 0;
+}
+
+static void __exit libcxgbi_exit_module(void)
+{
+	cxgbi_device_unregister_all(0xFF);
+	return;
+}
+
+module_init(libcxgbi_init_module);
+module_exit(libcxgbi_exit_module);