/*
 * iSCSI transport class definitions
 *
 * Copyright (C) IBM Corporation, 2004
 * Copyright (C) Mike Christie, 2004 - 2005
 * Copyright (C) Dmitry Yusupov, 2004 - 2005
 * Copyright (C) Alex Aizman, 2004 - 2005
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/bsg-lib.h>
#include <linux/idr.h>
#include <linux/list.h>
#include <net/tcp.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_iscsi.h>
#include <scsi/iscsi_if.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_bsg_iscsi.h>

#define ISCSI_TRANSPORT_VERSION "2.0-870"

static int dbg_session;
module_param_named(debug_session, dbg_session, int,
                   S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug_session,
                 "Turn on debugging for sessions in scsi_transport_iscsi "
                 "module. Set to 1 to turn on, and zero to turn off. Default "
                 "is off.");

static int dbg_conn;
module_param_named(debug_conn, dbg_conn, int,
                   S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug_conn,
                 "Turn on debugging for connections in scsi_transport_iscsi "
                 "module. Set to 1 to turn on, and zero to turn off. Default "
                 "is off.");

#define ISCSI_DBG_TRANS_SESSION(_session, dbg_fmt, arg...)              \
        do {                                                            \
                if (dbg_session)                                        \
                        iscsi_cls_session_printk(KERN_INFO, _session,   \
                                                 "%s: " dbg_fmt,        \
                                                 __func__, ##arg);      \
        } while (0);

#define ISCSI_DBG_TRANS_CONN(_conn, dbg_fmt, arg...)                    \
        do {                                                            \
                if (dbg_conn)                                           \
                        iscsi_cls_conn_printk(KERN_INFO, _conn,         \
                                              "%s: " dbg_fmt,           \
                                              __func__, ##arg); \
        } while (0);

struct iscsi_internal {
        struct scsi_transport_template t;
        struct iscsi_transport *iscsi_transport;
        struct list_head list;
        struct device dev;

        struct transport_container conn_cont;
        struct transport_container session_cont;
};

static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
static struct workqueue_struct *iscsi_eh_timer_workq;

static DEFINE_IDA(iscsi_sess_ida);
/*
 * list of registered transports and lock that must
 * be held while accessing list. The iscsi_transport_lock must
 * be acquired after the rx_queue_mutex.
 */
static LIST_HEAD(iscsi_transports);
static DEFINE_SPINLOCK(iscsi_transport_lock);

#define to_iscsi_internal(tmpl) \
        container_of(tmpl, struct iscsi_internal, t)

#define dev_to_iscsi_internal(_dev) \
        container_of(_dev, struct iscsi_internal, dev)

static void iscsi_transport_release(struct device *dev)
{
        struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
        kfree(priv);
}

/*
 * iscsi_transport_class represents the iscsi_transports that are
 * registered.
 */
static struct class iscsi_transport_class = {
        .name = "iscsi_transport",
        .dev_release = iscsi_transport_release,
};

static ssize_t
show_transport_handle(struct device *dev, struct device_attribute *attr,
                      char *buf)
{
        struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
        return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
}
static DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);

#define show_transport_attr(name, format)                               \
static ssize_t                                                          \
show_transport_##name(struct device *dev,                               \
                      struct device_attribute *attr,char *buf)          \
{                                                                       \
        struct iscsi_internal *priv = dev_to_iscsi_internal(dev);       \
        return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
}                                                                       \
static DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);

show_transport_attr(caps, "0x%x");

static struct attribute *iscsi_transport_attrs[] = {
        &dev_attr_handle.attr,
        &dev_attr_caps.attr,
        NULL,
};

static struct attribute_group iscsi_transport_group = {
        .attrs = iscsi_transport_attrs,
};

/*
 * iSCSI endpoint attrs
 */
#define iscsi_dev_to_endpoint(_dev) \
        container_of(_dev, struct iscsi_endpoint, dev)

#define ISCSI_ATTR(_prefix,_name,_mode,_show,_store)    \
struct device_attribute dev_attr_##_prefix##_##_name =  \
        __ATTR(_name,_mode,_show,_store)

static void iscsi_endpoint_release(struct device *dev)
{
        struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
        kfree(ep);
}

static struct class iscsi_endpoint_class = {
        .name = "iscsi_endpoint",
        .dev_release = iscsi_endpoint_release,
};

static ssize_t
show_ep_handle(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
        return sprintf(buf, "%llu\n", (unsigned long long) ep->id);
}
static ISCSI_ATTR(ep, handle, S_IRUGO, show_ep_handle, NULL);

static struct attribute *iscsi_endpoint_attrs[] = {
        &dev_attr_ep_handle.attr,
        NULL,
};

static struct attribute_group iscsi_endpoint_group = {
        .attrs = iscsi_endpoint_attrs,
};

#define ISCSI_MAX_EPID -1

static int iscsi_match_epid(struct device *dev, const void *data)
{
        struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
        const uint64_t *epid = data;

        return *epid == ep->id;
}

struct iscsi_endpoint *
iscsi_create_endpoint(int dd_size)
{
        struct device *dev;
        struct iscsi_endpoint *ep;
        uint64_t id;
        int err;

        for (id = 1; id < ISCSI_MAX_EPID; id++) {
                dev = class_find_device(&iscsi_endpoint_class, NULL, &id,
                                        iscsi_match_epid);
                if (!dev)
                        break;
        }
        if (id == ISCSI_MAX_EPID) {
                printk(KERN_ERR "Too many connections. Max supported %u\n",
                       ISCSI_MAX_EPID - 1);
                return NULL;
        }

        ep = kzalloc(sizeof(*ep) + dd_size, GFP_KERNEL);
        if (!ep)
                return NULL;

        ep->id = id;
        ep->dev.class = &iscsi_endpoint_class;
        dev_set_name(&ep->dev, "ep-%llu", (unsigned long long) id);
        err = device_register(&ep->dev);
        if (err)
                goto free_ep;

        err = sysfs_create_group(&ep->dev.kobj, &iscsi_endpoint_group);
        if (err)
                goto unregister_dev;

        if (dd_size)
                ep->dd_data = &ep[1];
        return ep;

unregister_dev:
        device_unregister(&ep->dev);
        return NULL;

free_ep:
        kfree(ep);
        return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_create_endpoint);

void iscsi_destroy_endpoint(struct iscsi_endpoint *ep)
{
        sysfs_remove_group(&ep->dev.kobj, &iscsi_endpoint_group);
        device_unregister(&ep->dev);
}
EXPORT_SYMBOL_GPL(iscsi_destroy_endpoint);

struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
{
        struct iscsi_endpoint *ep;
        struct device *dev;

        dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
                                iscsi_match_epid);
        if (!dev)
                return NULL;

        ep = iscsi_dev_to_endpoint(dev);
        /*
         * we can drop this now because the interface will prevent
         * removals and lookups from racing.
         */
        put_device(dev);
        return ep;
}
EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);

/*
 * Interface to display network param to sysfs
 */

static void iscsi_iface_release(struct device *dev)
{
        struct iscsi_iface *iface = iscsi_dev_to_iface(dev);
        struct device *parent = iface->dev.parent;

        kfree(iface);
        put_device(parent);
}


static struct class iscsi_iface_class = {
        .name = "iscsi_iface",
        .dev_release = iscsi_iface_release,
};

#define ISCSI_IFACE_ATTR(_prefix, _name, _mode, _show, _store)  \
struct device_attribute dev_attr_##_prefix##_##_name =          \
        __ATTR(_name, _mode, _show, _store)

/* iface attrs show */
#define iscsi_iface_attr_show(type, name, param_type, param)            \
static ssize_t                                                          \
show_##type##_##name(struct device *dev, struct device_attribute *attr, \
                     char *buf)                                         \
{                                                                       \
        struct iscsi_iface *iface = iscsi_dev_to_iface(dev);            \
        struct iscsi_transport *t = iface->transport;                   \
        return t->get_iface_param(iface, param_type, param, buf);       \
}                                                                       \

#define iscsi_iface_net_attr(type, name, param)                         \
        iscsi_iface_attr_show(type, name, ISCSI_NET_PARAM, param)       \
static ISCSI_IFACE_ATTR(type, name, S_IRUGO, show_##type##_##name, NULL);

/* generic read only ipvi4 attribute */
iscsi_iface_net_attr(ipv4_iface, ipaddress, ISCSI_NET_PARAM_IPV4_ADDR);
iscsi_iface_net_attr(ipv4_iface, gateway, ISCSI_NET_PARAM_IPV4_GW);
iscsi_iface_net_attr(ipv4_iface, subnet, ISCSI_NET_PARAM_IPV4_SUBNET);
iscsi_iface_net_attr(ipv4_iface, bootproto, ISCSI_NET_PARAM_IPV4_BOOTPROTO);

/* generic read only ipv6 attribute */
iscsi_iface_net_attr(ipv6_iface, ipaddress, ISCSI_NET_PARAM_IPV6_ADDR);
iscsi_iface_net_attr(ipv6_iface, link_local_addr, ISCSI_NET_PARAM_IPV6_LINKLOCAL);
iscsi_iface_net_attr(ipv6_iface, router_addr, ISCSI_NET_PARAM_IPV6_ROUTER);
iscsi_iface_net_attr(ipv6_iface, ipaddr_autocfg,
                     ISCSI_NET_PARAM_IPV6_ADDR_AUTOCFG);
iscsi_iface_net_attr(ipv6_iface, link_local_autocfg,
                     ISCSI_NET_PARAM_IPV6_LINKLOCAL_AUTOCFG);

/* common read only iface attribute */
iscsi_iface_net_attr(iface, enabled, ISCSI_NET_PARAM_IFACE_ENABLE);
iscsi_iface_net_attr(iface, vlan_id, ISCSI_NET_PARAM_VLAN_ID);
iscsi_iface_net_attr(iface, vlan_priority, ISCSI_NET_PARAM_VLAN_PRIORITY);
iscsi_iface_net_attr(iface, vlan_enabled, ISCSI_NET_PARAM_VLAN_ENABLED);
iscsi_iface_net_attr(iface, mtu, ISCSI_NET_PARAM_MTU);
iscsi_iface_net_attr(iface, port, ISCSI_NET_PARAM_PORT);

static umode_t iscsi_iface_attr_is_visible(struct kobject *kobj,
                                          struct attribute *attr, int i)
{
        struct device *dev = container_of(kobj, struct device, kobj);
        struct iscsi_iface *iface = iscsi_dev_to_iface(dev);
        struct iscsi_transport *t = iface->transport;
        int param;

        if (attr == &dev_attr_iface_enabled.attr)
                param = ISCSI_NET_PARAM_IFACE_ENABLE;
        else if (attr == &dev_attr_iface_vlan_id.attr)
                param = ISCSI_NET_PARAM_VLAN_ID;
        else if (attr == &dev_attr_iface_vlan_priority.attr)
                param = ISCSI_NET_PARAM_VLAN_PRIORITY;
        else if (attr == &dev_attr_iface_vlan_enabled.attr)
                param = ISCSI_NET_PARAM_VLAN_ENABLED;
        else if (attr == &dev_attr_iface_mtu.attr)
                param = ISCSI_NET_PARAM_MTU;
        else if (attr == &dev_attr_iface_port.attr)
                param = ISCSI_NET_PARAM_PORT;
        else if (iface->iface_type == ISCSI_IFACE_TYPE_IPV4) {
                if (attr == &dev_attr_ipv4_iface_ipaddress.attr)
                        param = ISCSI_NET_PARAM_IPV4_ADDR;
                else if (attr == &dev_attr_ipv4_iface_gateway.attr)
                        param = ISCSI_NET_PARAM_IPV4_GW;
                else if (attr == &dev_attr_ipv4_iface_subnet.attr)
                        param = ISCSI_NET_PARAM_IPV4_SUBNET;
                else if (attr == &dev_attr_ipv4_iface_bootproto.attr)
                        param = ISCSI_NET_PARAM_IPV4_BOOTPROTO;
                else
                        return 0;
        } else if (iface->iface_type == ISCSI_IFACE_TYPE_IPV6) {
                if (attr == &dev_attr_ipv6_iface_ipaddress.attr)
                        param = ISCSI_NET_PARAM_IPV6_ADDR;
                else if (attr == &dev_attr_ipv6_iface_link_local_addr.attr)
                        param = ISCSI_NET_PARAM_IPV6_LINKLOCAL;
                else if (attr == &dev_attr_ipv6_iface_router_addr.attr)
                        param = ISCSI_NET_PARAM_IPV6_ROUTER;
                else if (attr == &dev_attr_ipv6_iface_ipaddr_autocfg.attr)
                        param = ISCSI_NET_PARAM_IPV6_ADDR_AUTOCFG;
                else if (attr == &dev_attr_ipv6_iface_link_local_autocfg.attr)
                        param = ISCSI_NET_PARAM_IPV6_LINKLOCAL_AUTOCFG;
                else
                        return 0;
        } else {
                WARN_ONCE(1, "Invalid iface attr");
                return 0;
        }

        return t->attr_is_visible(ISCSI_NET_PARAM, param);
}

static struct attribute *iscsi_iface_attrs[] = {
        &dev_attr_iface_enabled.attr,
        &dev_attr_iface_vlan_id.attr,
        &dev_attr_iface_vlan_priority.attr,
        &dev_attr_iface_vlan_enabled.attr,
        &dev_attr_ipv4_iface_ipaddress.attr,
        &dev_attr_ipv4_iface_gateway.attr,
        &dev_attr_ipv4_iface_subnet.attr,
        &dev_attr_ipv4_iface_bootproto.attr,
        &dev_attr_ipv6_iface_ipaddress.attr,
        &dev_attr_ipv6_iface_link_local_addr.attr,
        &dev_attr_ipv6_iface_router_addr.attr,
        &dev_attr_ipv6_iface_ipaddr_autocfg.attr,
        &dev_attr_ipv6_iface_link_local_autocfg.attr,
        &dev_attr_iface_mtu.attr,
        &dev_attr_iface_port.attr,
        NULL,
};

static struct attribute_group iscsi_iface_group = {
        .attrs = iscsi_iface_attrs,
        .is_visible = iscsi_iface_attr_is_visible,
};

struct iscsi_iface *
iscsi_create_iface(struct Scsi_Host *shost, struct iscsi_transport *transport,
                   uint32_t iface_type, uint32_t iface_num, int dd_size)
{
        struct iscsi_iface *iface;
        int err;

        iface = kzalloc(sizeof(*iface) + dd_size, GFP_KERNEL);
        if (!iface)
                return NULL;

        iface->transport = transport;
        iface->iface_type = iface_type;
        iface->iface_num = iface_num;
        iface->dev.release = iscsi_iface_release;
        iface->dev.class = &iscsi_iface_class;
        /* parent reference released in iscsi_iface_release */
        iface->dev.parent = get_device(&shost->shost_gendev);
        if (iface_type == ISCSI_IFACE_TYPE_IPV4)
                dev_set_name(&iface->dev, "ipv4-iface-%u-%u", shost->host_no,
                             iface_num);
        else
                dev_set_name(&iface->dev, "ipv6-iface-%u-%u", shost->host_no,
                             iface_num);

        err = device_register(&iface->dev);
        if (err)
                goto free_iface;

        err = sysfs_create_group(&iface->dev.kobj, &iscsi_iface_group);
        if (err)
                goto unreg_iface;

        if (dd_size)
                iface->dd_data = &iface[1];
        return iface;

unreg_iface:
        device_unregister(&iface->dev);
        return NULL;

free_iface:
        put_device(iface->dev.parent);
        kfree(iface);
        return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_create_iface);

void iscsi_destroy_iface(struct iscsi_iface *iface)
{
        sysfs_remove_group(&iface->dev.kobj, &iscsi_iface_group);
        device_unregister(&iface->dev);
}
EXPORT_SYMBOL_GPL(iscsi_destroy_iface);

/*
 * Interface to display flash node params to sysfs
 */

#define ISCSI_FLASHNODE_ATTR(_prefix, _name, _mode, _show, _store)      \
struct device_attribute dev_attr_##_prefix##_##_name =                  \
        __ATTR(_name, _mode, _show, _store)

/* flash node session attrs show */
#define iscsi_flashnode_sess_attr_show(type, name, param)               \
static ssize_t                                                          \
show_##type##_##name(struct device *dev, struct device_attribute *attr, \
                     char *buf)                                         \
{                                                                       \
        struct iscsi_bus_flash_session *fnode_sess =                    \
                                        iscsi_dev_to_flash_session(dev);\
        struct iscsi_transport *t = fnode_sess->transport;              \
        return t->get_flashnode_param(fnode_sess, param, buf);          \
}                                                                       \


#define iscsi_flashnode_sess_attr(type, name, param)                    \
        iscsi_flashnode_sess_attr_show(type, name, param)               \
static ISCSI_FLASHNODE_ATTR(type, name, S_IRUGO,                        \
                            show_##type##_##name, NULL);

/* Flash node session attributes */

iscsi_flashnode_sess_attr(fnode, auto_snd_tgt_disable,
                          ISCSI_FLASHNODE_AUTO_SND_TGT_DISABLE);
iscsi_flashnode_sess_attr(fnode, discovery_session,
                          ISCSI_FLASHNODE_DISCOVERY_SESS);
iscsi_flashnode_sess_attr(fnode, portal_type, ISCSI_FLASHNODE_PORTAL_TYPE);
iscsi_flashnode_sess_attr(fnode, entry_enable, ISCSI_FLASHNODE_ENTRY_EN);
iscsi_flashnode_sess_attr(fnode, immediate_data, ISCSI_FLASHNODE_IMM_DATA_EN);
iscsi_flashnode_sess_attr(fnode, initial_r2t, ISCSI_FLASHNODE_INITIAL_R2T_EN);
iscsi_flashnode_sess_attr(fnode, data_seq_in_order,
                          ISCSI_FLASHNODE_DATASEQ_INORDER);
iscsi_flashnode_sess_attr(fnode, data_pdu_in_order,
                          ISCSI_FLASHNODE_PDU_INORDER);
iscsi_flashnode_sess_attr(fnode, chap_auth, ISCSI_FLASHNODE_CHAP_AUTH_EN);
iscsi_flashnode_sess_attr(fnode, discovery_logout,
                          ISCSI_FLASHNODE_DISCOVERY_LOGOUT_EN);
iscsi_flashnode_sess_attr(fnode, bidi_chap, ISCSI_FLASHNODE_BIDI_CHAP_EN);
iscsi_flashnode_sess_attr(fnode, discovery_auth_optional,
                          ISCSI_FLASHNODE_DISCOVERY_AUTH_OPTIONAL);
iscsi_flashnode_sess_attr(fnode, erl, ISCSI_FLASHNODE_ERL);
iscsi_flashnode_sess_attr(fnode, first_burst_len, ISCSI_FLASHNODE_FIRST_BURST);
iscsi_flashnode_sess_attr(fnode, def_time2wait, ISCSI_FLASHNODE_DEF_TIME2WAIT);
iscsi_flashnode_sess_attr(fnode, def_time2retain,
                          ISCSI_FLASHNODE_DEF_TIME2RETAIN);
iscsi_flashnode_sess_attr(fnode, max_outstanding_r2t, ISCSI_FLASHNODE_MAX_R2T);
iscsi_flashnode_sess_attr(fnode, isid, ISCSI_FLASHNODE_ISID);
iscsi_flashnode_sess_attr(fnode, tsid, ISCSI_FLASHNODE_TSID);
iscsi_flashnode_sess_attr(fnode, max_burst_len, ISCSI_FLASHNODE_MAX_BURST);
iscsi_flashnode_sess_attr(fnode, def_taskmgmt_tmo,
                          ISCSI_FLASHNODE_DEF_TASKMGMT_TMO);
iscsi_flashnode_sess_attr(fnode, targetalias, ISCSI_FLASHNODE_ALIAS);
iscsi_flashnode_sess_attr(fnode, targetname, ISCSI_FLASHNODE_NAME);
iscsi_flashnode_sess_attr(fnode, tpgt, ISCSI_FLASHNODE_TPGT);
iscsi_flashnode_sess_attr(fnode, discovery_parent_idx,
                          ISCSI_FLASHNODE_DISCOVERY_PARENT_IDX);
iscsi_flashnode_sess_attr(fnode, discovery_parent_type,
                          ISCSI_FLASHNODE_DISCOVERY_PARENT_TYPE);
iscsi_flashnode_sess_attr(fnode, chap_in_idx, ISCSI_FLASHNODE_CHAP_IN_IDX);
iscsi_flashnode_sess_attr(fnode, chap_out_idx, ISCSI_FLASHNODE_CHAP_OUT_IDX);
iscsi_flashnode_sess_attr(fnode, username, ISCSI_FLASHNODE_USERNAME);
iscsi_flashnode_sess_attr(fnode, username_in, ISCSI_FLASHNODE_USERNAME_IN);
iscsi_flashnode_sess_attr(fnode, password, ISCSI_FLASHNODE_PASSWORD);
iscsi_flashnode_sess_attr(fnode, password_in, ISCSI_FLASHNODE_PASSWORD_IN);
iscsi_flashnode_sess_attr(fnode, is_boot_target, ISCSI_FLASHNODE_IS_BOOT_TGT);

static struct attribute *iscsi_flashnode_sess_attrs[] = {
        &dev_attr_fnode_auto_snd_tgt_disable.attr,
        &dev_attr_fnode_discovery_session.attr,
        &dev_attr_fnode_portal_type.attr,
        &dev_attr_fnode_entry_enable.attr,
        &dev_attr_fnode_immediate_data.attr,
        &dev_attr_fnode_initial_r2t.attr,
        &dev_attr_fnode_data_seq_in_order.attr,
        &dev_attr_fnode_data_pdu_in_order.attr,
        &dev_attr_fnode_chap_auth.attr,
        &dev_attr_fnode_discovery_logout.attr,
        &dev_attr_fnode_bidi_chap.attr,
        &dev_attr_fnode_discovery_auth_optional.attr,
        &dev_attr_fnode_erl.attr,
        &dev_attr_fnode_first_burst_len.attr,
        &dev_attr_fnode_def_time2wait.attr,
        &dev_attr_fnode_def_time2retain.attr,
        &dev_attr_fnode_max_outstanding_r2t.attr,
        &dev_attr_fnode_isid.attr,
        &dev_attr_fnode_tsid.attr,
        &dev_attr_fnode_max_burst_len.attr,
        &dev_attr_fnode_def_taskmgmt_tmo.attr,
        &dev_attr_fnode_targetalias.attr,
        &dev_attr_fnode_targetname.attr,
        &dev_attr_fnode_tpgt.attr,
        &dev_attr_fnode_discovery_parent_idx.attr,
        &dev_attr_fnode_discovery_parent_type.attr,
        &dev_attr_fnode_chap_in_idx.attr,
        &dev_attr_fnode_chap_out_idx.attr,
        &dev_attr_fnode_username.attr,
        &dev_attr_fnode_username_in.attr,
        &dev_attr_fnode_password.attr,
        &dev_attr_fnode_password_in.attr,
        &dev_attr_fnode_is_boot_target.attr,
        NULL,
};

static umode_t iscsi_flashnode_sess_attr_is_visible(struct kobject *kobj,
                                                    struct attribute *attr,
                                                    int i)
{
        struct device *dev = container_of(kobj, struct device, kobj);
        struct iscsi_bus_flash_session *fnode_sess =
                                                iscsi_dev_to_flash_session(dev);
        struct iscsi_transport *t = fnode_sess->transport;
        int param;

        if (attr == &dev_attr_fnode_auto_snd_tgt_disable.attr) {
                param = ISCSI_FLASHNODE_AUTO_SND_TGT_DISABLE;
        } else if (attr == &dev_attr_fnode_discovery_session.attr) {
                param = ISCSI_FLASHNODE_DISCOVERY_SESS;
        } else if (attr == &dev_attr_fnode_portal_type.attr) {
                param = ISCSI_FLASHNODE_PORTAL_TYPE;
        } else if (attr == &dev_attr_fnode_entry_enable.attr) {
                param = ISCSI_FLASHNODE_ENTRY_EN;
        } else if (attr == &dev_attr_fnode_immediate_data.attr) {
                param = ISCSI_FLASHNODE_IMM_DATA_EN;
        } else if (attr == &dev_attr_fnode_initial_r2t.attr) {
                param = ISCSI_FLASHNODE_INITIAL_R2T_EN;
        } else if (attr == &dev_attr_fnode_data_seq_in_order.attr) {
                param = ISCSI_FLASHNODE_DATASEQ_INORDER;
        } else if (attr == &dev_attr_fnode_data_pdu_in_order.attr) {
                param = ISCSI_FLASHNODE_PDU_INORDER;
        } else if (attr == &dev_attr_fnode_chap_auth.attr) {
                param = ISCSI_FLASHNODE_CHAP_AUTH_EN;
        } else if (attr == &dev_attr_fnode_discovery_logout.attr) {
                param = ISCSI_FLASHNODE_DISCOVERY_LOGOUT_EN;
        } else if (attr == &dev_attr_fnode_bidi_chap.attr) {
                param = ISCSI_FLASHNODE_BIDI_CHAP_EN;
        } else if (attr == &dev_attr_fnode_discovery_auth_optional.attr) {
                param = ISCSI_FLASHNODE_DISCOVERY_AUTH_OPTIONAL;
        } else if (attr == &dev_attr_fnode_erl.attr) {
                param = ISCSI_FLASHNODE_ERL;
        } else if (attr == &dev_attr_fnode_first_burst_len.attr) {
                param = ISCSI_FLASHNODE_FIRST_BURST;
        } else if (attr == &dev_attr_fnode_def_time2wait.attr) {
                param = ISCSI_FLASHNODE_DEF_TIME2WAIT;
        } else if (attr == &dev_attr_fnode_def_time2retain.attr) {
                param = ISCSI_FLASHNODE_DEF_TIME2RETAIN;
        } else if (attr == &dev_attr_fnode_max_outstanding_r2t.attr) {
                param = ISCSI_FLASHNODE_MAX_R2T;
        } else if (attr == &dev_attr_fnode_isid.attr) {
                param = ISCSI_FLASHNODE_ISID;
        } else if (attr == &dev_attr_fnode_tsid.attr) {
                param = ISCSI_FLASHNODE_TSID;
        } else if (attr == &dev_attr_fnode_max_burst_len.attr) {
                param = ISCSI_FLASHNODE_MAX_BURST;
        } else if (attr == &dev_attr_fnode_def_taskmgmt_tmo.attr) {
                param = ISCSI_FLASHNODE_DEF_TASKMGMT_TMO;
        } else if (attr == &dev_attr_fnode_targetalias.attr) {
                param = ISCSI_FLASHNODE_ALIAS;
        } else if (attr == &dev_attr_fnode_targetname.attr) {
                param = ISCSI_FLASHNODE_NAME;
        } else if (attr == &dev_attr_fnode_tpgt.attr) {
                param = ISCSI_FLASHNODE_TPGT;
        } else if (attr == &dev_attr_fnode_discovery_parent_idx.attr) {
                param = ISCSI_FLASHNODE_DISCOVERY_PARENT_IDX;
        } else if (attr == &dev_attr_fnode_discovery_parent_type.attr) {
                param = ISCSI_FLASHNODE_DISCOVERY_PARENT_TYPE;
        } else if (attr == &dev_attr_fnode_chap_in_idx.attr) {
                param = ISCSI_FLASHNODE_CHAP_IN_IDX;
        } else if (attr == &dev_attr_fnode_chap_out_idx.attr) {
                param = ISCSI_FLASHNODE_CHAP_OUT_IDX;
        } else if (attr == &dev_attr_fnode_username.attr) {
                param = ISCSI_FLASHNODE_USERNAME;
        } else if (attr == &dev_attr_fnode_username_in.attr) {
                param = ISCSI_FLASHNODE_USERNAME_IN;
        } else if (attr == &dev_attr_fnode_password.attr) {
                param = ISCSI_FLASHNODE_PASSWORD;
        } else if (attr == &dev_attr_fnode_password_in.attr) {
                param = ISCSI_FLASHNODE_PASSWORD_IN;
        } else if (attr == &dev_attr_fnode_is_boot_target.attr) {
                param = ISCSI_FLASHNODE_IS_BOOT_TGT;
        } else {
                WARN_ONCE(1, "Invalid flashnode session attr");
                return 0;
        }

        return t->attr_is_visible(ISCSI_FLASHNODE_PARAM, param);
}

static struct attribute_group iscsi_flashnode_sess_attr_group = {
        .attrs = iscsi_flashnode_sess_attrs,
        .is_visible = iscsi_flashnode_sess_attr_is_visible,
};

static const struct attribute_group *iscsi_flashnode_sess_attr_groups[] = {
        &iscsi_flashnode_sess_attr_group,
        NULL,
};

static void iscsi_flashnode_sess_release(struct device *dev)
{
        struct iscsi_bus_flash_session *fnode_sess =
                                                iscsi_dev_to_flash_session(dev);

        kfree(fnode_sess->targetname);
        kfree(fnode_sess->targetalias);
        kfree(fnode_sess->portal_type);
        kfree(fnode_sess);
}

struct device_type iscsi_flashnode_sess_dev_type = {
        .name = "iscsi_flashnode_sess_dev_type",
        .groups = iscsi_flashnode_sess_attr_groups,
        .release = iscsi_flashnode_sess_release,
};

/* flash node connection attrs show */
#define iscsi_flashnode_conn_attr_show(type, name, param)               \
static ssize_t                                                          \
show_##type##_##name(struct device *dev, struct device_attribute *attr, \
                     char *buf)                                         \
{                                                                       \
        struct iscsi_bus_flash_conn *fnode_conn = iscsi_dev_to_flash_conn(dev);\
        struct iscsi_bus_flash_session *fnode_sess =                    \
                                iscsi_flash_conn_to_flash_session(fnode_conn);\
        struct iscsi_transport *t = fnode_conn->transport;              \
        return t->get_flashnode_param(fnode_sess, param, buf);          \
}                                                                       \


#define iscsi_flashnode_conn_attr(type, name, param)                    \
        iscsi_flashnode_conn_attr_show(type, name, param)               \
static ISCSI_FLASHNODE_ATTR(type, name, S_IRUGO,                        \
                            show_##type##_##name, NULL);

/* Flash node connection attributes */

iscsi_flashnode_conn_attr(fnode, is_fw_assigned_ipv6,
                          ISCSI_FLASHNODE_IS_FW_ASSIGNED_IPV6);
iscsi_flashnode_conn_attr(fnode, header_digest, ISCSI_FLASHNODE_HDR_DGST_EN);
iscsi_flashnode_conn_attr(fnode, data_digest, ISCSI_FLASHNODE_DATA_DGST_EN);
iscsi_flashnode_conn_attr(fnode, snack_req, ISCSI_FLASHNODE_SNACK_REQ_EN);
iscsi_flashnode_conn_attr(fnode, tcp_timestamp_stat,
                          ISCSI_FLASHNODE_TCP_TIMESTAMP_STAT);
iscsi_flashnode_conn_attr(fnode, tcp_nagle_disable,
                          ISCSI_FLASHNODE_TCP_NAGLE_DISABLE);
iscsi_flashnode_conn_attr(fnode, tcp_wsf_disable,
                          ISCSI_FLASHNODE_TCP_WSF_DISABLE);
iscsi_flashnode_conn_attr(fnode, tcp_timer_scale,
                          ISCSI_FLASHNODE_TCP_TIMER_SCALE);
iscsi_flashnode_conn_attr(fnode, tcp_timestamp_enable,
                          ISCSI_FLASHNODE_TCP_TIMESTAMP_EN);
iscsi_flashnode_conn_attr(fnode, fragment_disable,
                          ISCSI_FLASHNODE_IP_FRAG_DISABLE);
iscsi_flashnode_conn_attr(fnode, keepalive_tmo, ISCSI_FLASHNODE_KEEPALIVE_TMO);
iscsi_flashnode_conn_attr(fnode, port, ISCSI_FLASHNODE_PORT);
iscsi_flashnode_conn_attr(fnode, ipaddress, ISCSI_FLASHNODE_IPADDR);
iscsi_flashnode_conn_attr(fnode, max_recv_dlength,
                          ISCSI_FLASHNODE_MAX_RECV_DLENGTH);
iscsi_flashnode_conn_attr(fnode, max_xmit_dlength,
                          ISCSI_FLASHNODE_MAX_XMIT_DLENGTH);
iscsi_flashnode_conn_attr(fnode, local_port, ISCSI_FLASHNODE_LOCAL_PORT);
iscsi_flashnode_conn_attr(fnode, ipv4_tos, ISCSI_FLASHNODE_IPV4_TOS);
iscsi_flashnode_conn_attr(fnode, ipv6_traffic_class, ISCSI_FLASHNODE_IPV6_TC);
iscsi_flashnode_conn_attr(fnode, ipv6_flow_label,
                          ISCSI_FLASHNODE_IPV6_FLOW_LABEL);
iscsi_flashnode_conn_attr(fnode, redirect_ipaddr,
                          ISCSI_FLASHNODE_REDIRECT_IPADDR);
iscsi_flashnode_conn_attr(fnode, max_segment_size,
                          ISCSI_FLASHNODE_MAX_SEGMENT_SIZE);
iscsi_flashnode_conn_attr(fnode, link_local_ipv6,
                          ISCSI_FLASHNODE_LINK_LOCAL_IPV6);
iscsi_flashnode_conn_attr(fnode, tcp_xmit_wsf, ISCSI_FLASHNODE_TCP_XMIT_WSF);
iscsi_flashnode_conn_attr(fnode, tcp_recv_wsf, ISCSI_FLASHNODE_TCP_RECV_WSF);
iscsi_flashnode_conn_attr(fnode, statsn, ISCSI_FLASHNODE_STATSN);
iscsi_flashnode_conn_attr(fnode, exp_statsn, ISCSI_FLASHNODE_EXP_STATSN);

static struct attribute *iscsi_flashnode_conn_attrs[] = {
        &dev_attr_fnode_is_fw_assigned_ipv6.attr,
        &dev_attr_fnode_header_digest.attr,
        &dev_attr_fnode_data_digest.attr,
        &dev_attr_fnode_snack_req.attr,
        &dev_attr_fnode_tcp_timestamp_stat.attr,
        &dev_attr_fnode_tcp_nagle_disable.attr,
        &dev_attr_fnode_tcp_wsf_disable.attr,
        &dev_attr_fnode_tcp_timer_scale.attr,
        &dev_attr_fnode_tcp_timestamp_enable.attr,
        &dev_attr_fnode_fragment_disable.attr,
        &dev_attr_fnode_max_recv_dlength.attr,
        &dev_attr_fnode_max_xmit_dlength.attr,
        &dev_attr_fnode_keepalive_tmo.attr,
        &dev_attr_fnode_port.attr,
        &dev_attr_fnode_ipaddress.attr,
        &dev_attr_fnode_redirect_ipaddr.attr,
        &dev_attr_fnode_max_segment_size.attr,
        &dev_attr_fnode_local_port.attr,
        &dev_attr_fnode_ipv4_tos.attr,
        &dev_attr_fnode_ipv6_traffic_class.attr,
        &dev_attr_fnode_ipv6_flow_label.attr,
        &dev_attr_fnode_link_local_ipv6.attr,
        &dev_attr_fnode_tcp_xmit_wsf.attr,
        &dev_attr_fnode_tcp_recv_wsf.attr,
        &dev_attr_fnode_statsn.attr,
        &dev_attr_fnode_exp_statsn.attr,
        NULL,
};

static umode_t iscsi_flashnode_conn_attr_is_visible(struct kobject *kobj,
                                                    struct attribute *attr,
                                                    int i)
{
        struct device *dev = container_of(kobj, struct device, kobj);
        struct iscsi_bus_flash_conn *fnode_conn = iscsi_dev_to_flash_conn(dev);
        struct iscsi_transport *t = fnode_conn->transport;
        int param;

        if (attr == &dev_attr_fnode_is_fw_assigned_ipv6.attr) {
                param = ISCSI_FLASHNODE_IS_FW_ASSIGNED_IPV6;
        } else if (attr == &dev_attr_fnode_header_digest.attr) {
                param = ISCSI_FLASHNODE_HDR_DGST_EN;
        } else if (attr == &dev_attr_fnode_data_digest.attr) {
                param = ISCSI_FLASHNODE_DATA_DGST_EN;
        } else if (attr == &dev_attr_fnode_snack_req.attr) {
                param = ISCSI_FLASHNODE_SNACK_REQ_EN;
        } else if (attr == &dev_attr_fnode_tcp_timestamp_stat.attr) {
                param = ISCSI_FLASHNODE_TCP_TIMESTAMP_STAT;
        } else if (attr == &dev_attr_fnode_tcp_nagle_disable.attr) {
                param = ISCSI_FLASHNODE_TCP_NAGLE_DISABLE;
        } else if (attr == &dev_attr_fnode_tcp_wsf_disable.attr) {
                param = ISCSI_FLASHNODE_TCP_WSF_DISABLE;
        } else if (attr == &dev_attr_fnode_tcp_timer_scale.attr) {
                param = ISCSI_FLASHNODE_TCP_TIMER_SCALE;
        } else if (attr == &dev_attr_fnode_tcp_timestamp_enable.attr) {
                param = ISCSI_FLASHNODE_TCP_TIMESTAMP_EN;
        } else if (attr == &dev_attr_fnode_fragment_disable.attr) {
                param = ISCSI_FLASHNODE_IP_FRAG_DISABLE;
        } else if (attr == &dev_attr_fnode_max_recv_dlength.attr) {
                param = ISCSI_FLASHNODE_MAX_RECV_DLENGTH;
        } else if (attr == &dev_attr_fnode_max_xmit_dlength.attr) {
                param = ISCSI_FLASHNODE_MAX_XMIT_DLENGTH;
        } else if (attr == &dev_attr_fnode_keepalive_tmo.attr) {
                param = ISCSI_FLASHNODE_KEEPALIVE_TMO;
        } else if (attr == &dev_attr_fnode_port.attr) {
                param = ISCSI_FLASHNODE_PORT;
        } else if (attr == &dev_attr_fnode_ipaddress.attr) {
                param = ISCSI_FLASHNODE_IPADDR;
        } else if (attr == &dev_attr_fnode_redirect_ipaddr.attr) {
                param = ISCSI_FLASHNODE_REDIRECT_IPADDR;
        } else if (attr == &dev_attr_fnode_max_segment_size.attr) {
                param = ISCSI_FLASHNODE_MAX_SEGMENT_SIZE;
        } else if (attr == &dev_attr_fnode_local_port.attr) {
                param = ISCSI_FLASHNODE_LOCAL_PORT;
        } else if (attr == &dev_attr_fnode_ipv4_tos.attr) {
                param = ISCSI_FLASHNODE_IPV4_TOS;
        } else if (attr == &dev_attr_fnode_ipv6_traffic_class.attr) {
                param = ISCSI_FLASHNODE_IPV6_TC;
        } else if (attr == &dev_attr_fnode_ipv6_flow_label.attr) {
                param = ISCSI_FLASHNODE_IPV6_FLOW_LABEL;
        } else if (attr == &dev_attr_fnode_link_local_ipv6.attr) {
                param = ISCSI_FLASHNODE_LINK_LOCAL_IPV6;
        } else if (attr == &dev_attr_fnode_tcp_xmit_wsf.attr) {
                param = ISCSI_FLASHNODE_TCP_XMIT_WSF;
        } else if (attr == &dev_attr_fnode_tcp_recv_wsf.attr) {
                param = ISCSI_FLASHNODE_TCP_RECV_WSF;
        } else if (attr == &dev_attr_fnode_statsn.attr) {
                param = ISCSI_FLASHNODE_STATSN;
        } else if (attr == &dev_attr_fnode_exp_statsn.attr) {
                param = ISCSI_FLASHNODE_EXP_STATSN;
        } else {
                WARN_ONCE(1, "Invalid flashnode connection attr");
                return 0;
        }

        return t->attr_is_visible(ISCSI_FLASHNODE_PARAM, param);
}

static struct attribute_group iscsi_flashnode_conn_attr_group = {
        .attrs = iscsi_flashnode_conn_attrs,
        .is_visible = iscsi_flashnode_conn_attr_is_visible,
};

static const struct attribute_group *iscsi_flashnode_conn_attr_groups[] = {
        &iscsi_flashnode_conn_attr_group,
        NULL,
};

static void iscsi_flashnode_conn_release(struct device *dev)
{
        struct iscsi_bus_flash_conn *fnode_conn = iscsi_dev_to_flash_conn(dev);

        kfree(fnode_conn->ipaddress);
        kfree(fnode_conn->redirect_ipaddr);
        kfree(fnode_conn->link_local_ipv6_addr);
        kfree(fnode_conn);
}

struct device_type iscsi_flashnode_conn_dev_type = {
        .name = "iscsi_flashnode_conn_dev_type",
        .groups = iscsi_flashnode_conn_attr_groups,
        .release = iscsi_flashnode_conn_release,
};

struct bus_type iscsi_flashnode_bus;

int iscsi_flashnode_bus_match(struct device *dev,
                                     struct device_driver *drv)
{
        if (dev->bus == &iscsi_flashnode_bus)
                return 1;
        return 0;
}
EXPORT_SYMBOL_GPL(iscsi_flashnode_bus_match);

struct bus_type iscsi_flashnode_bus = {
        .name = "iscsi_flashnode",
        .match = &iscsi_flashnode_bus_match,
};

/**
 * iscsi_create_flashnode_sess - Add flashnode session entry in sysfs
 * @shost: pointer to host data
 * @index: index of flashnode to add in sysfs
 * @transport: pointer to transport data
 * @dd_size: total size to allocate
 *
 * Adds a sysfs entry for the flashnode session attributes
 *
 * Returns:
 *  pointer to allocated flashnode sess on sucess
 *  %NULL on failure
 */
struct iscsi_bus_flash_session *
iscsi_create_flashnode_sess(struct Scsi_Host *shost, int index,
                            struct iscsi_transport *transport,
                            int dd_size)
{
        struct iscsi_bus_flash_session *fnode_sess;
        int err;

        fnode_sess = kzalloc(sizeof(*fnode_sess) + dd_size, GFP_KERNEL);
        if (!fnode_sess)
                return NULL;

        fnode_sess->transport = transport;
        fnode_sess->target_id = index;
        fnode_sess->dev.type = &iscsi_flashnode_sess_dev_type;
        fnode_sess->dev.bus = &iscsi_flashnode_bus;
        fnode_sess->dev.parent = &shost->shost_gendev;
        dev_set_name(&fnode_sess->dev, "flashnode_sess-%u:%u",
                     shost->host_no, index);

        err = device_register(&fnode_sess->dev);
        if (err)
                goto free_fnode_sess;

        if (dd_size)
                fnode_sess->dd_data = &fnode_sess[1];

        return fnode_sess;

free_fnode_sess:
        kfree(fnode_sess);
        return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_create_flashnode_sess);

/**
 * iscsi_create_flashnode_conn - Add flashnode conn entry in sysfs
 * @shost: pointer to host data
 * @fnode_sess: pointer to the parent flashnode session entry
 * @transport: pointer to transport data
 * @dd_size: total size to allocate
 *
 * Adds a sysfs entry for the flashnode connection attributes
 *
 * Returns:
 *  pointer to allocated flashnode conn on success
 *  %NULL on failure
 */
struct iscsi_bus_flash_conn *
iscsi_create_flashnode_conn(struct Scsi_Host *shost,
                            struct iscsi_bus_flash_session *fnode_sess,
                            struct iscsi_transport *transport,
                            int dd_size)
{
        struct iscsi_bus_flash_conn *fnode_conn;
        int err;

        fnode_conn = kzalloc(sizeof(*fnode_conn) + dd_size, GFP_KERNEL);
        if (!fnode_conn)
                return NULL;

        fnode_conn->transport = transport;
        fnode_conn->dev.type = &iscsi_flashnode_conn_dev_type;
        fnode_conn->dev.bus = &iscsi_flashnode_bus;
        fnode_conn->dev.parent = &fnode_sess->dev;
        dev_set_name(&fnode_conn->dev, "flashnode_conn-%u:%u:0",
                     shost->host_no, fnode_sess->target_id);

        err = device_register(&fnode_conn->dev);
        if (err)
                goto free_fnode_conn;

        if (dd_size)
                fnode_conn->dd_data = &fnode_conn[1];

        return fnode_conn;

free_fnode_conn:
        kfree(fnode_conn);
        return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_create_flashnode_conn);

/**
 * iscsi_is_flashnode_conn_dev - verify passed device is to be flashnode conn
 * @dev: device to verify
 * @data: pointer to data containing value to use for verification
 *
 * Verifies if the passed device is flashnode conn device
 *
 * Returns:
 *  1 on success
 *  0 on failure
 */
int iscsi_is_flashnode_conn_dev(struct device *dev, void *data)
{
        return dev->bus == &iscsi_flashnode_bus;
}
EXPORT_SYMBOL_GPL(iscsi_is_flashnode_conn_dev);

static int iscsi_destroy_flashnode_conn(struct iscsi_bus_flash_conn *fnode_conn)
{
        device_unregister(&fnode_conn->dev);

        return 0;
}

static int flashnode_match_index(struct device *dev, void *data)
{
        struct iscsi_bus_flash_session *fnode_sess = NULL;
        int ret = 0;

        if (!iscsi_flashnode_bus_match(dev, NULL))
                goto exit_match_index;

        fnode_sess = iscsi_dev_to_flash_session(dev);
        ret = (fnode_sess->target_id == *((int *)data)) ? 1 : 0;

exit_match_index:
        return ret;
}

/**
 * iscsi_get_flashnode_by_index -finds flashnode session entry by index
 * @shost: pointer to host data
 * @idx: index to match
 *
 * Finds the flashnode session object for the passed index
 *
 * Returns:
 *  pointer to found flashnode session object on success
 *  %NULL on failure
 */
static struct iscsi_bus_flash_session *
iscsi_get_flashnode_by_index(struct Scsi_Host *shost, uint32_t idx)
{
        struct iscsi_bus_flash_session *fnode_sess = NULL;
        struct device *dev;

        dev = device_find_child(&shost->shost_gendev, &idx,
                                flashnode_match_index);
        if (dev)
                fnode_sess = iscsi_dev_to_flash_session(dev);

        return fnode_sess;
}

/**
 * iscsi_find_flashnode_sess - finds flashnode session entry
 * @shost: pointer to host data
 * @data: pointer to data containing value to use for comparison
 * @fn: function pointer that does actual comparison
 *
 * Finds the flashnode session object comparing the data passed using logic
 * defined in passed function pointer
 *
 * Returns:
 *  pointer to found flashnode session device object on success
 *  %NULL on failure
 */
struct device *
iscsi_find_flashnode_sess(struct Scsi_Host *shost, void *data,
                          int (*fn)(struct device *dev, void *data))
{
        return device_find_child(&shost->shost_gendev, data, fn);
}
EXPORT_SYMBOL_GPL(iscsi_find_flashnode_sess);

/**
 * iscsi_find_flashnode_conn - finds flashnode connection entry
 * @fnode_sess: pointer to parent flashnode session entry
 *
 * Finds the flashnode connection object comparing the data passed using logic
 * defined in passed function pointer
 *
 * Returns:
 *  pointer to found flashnode connection device object on success
 *  %NULL on failure
 */
struct device *
iscsi_find_flashnode_conn(struct iscsi_bus_flash_session *fnode_sess)
{
        return device_find_child(&fnode_sess->dev, NULL,
                                 iscsi_is_flashnode_conn_dev);
}
EXPORT_SYMBOL_GPL(iscsi_find_flashnode_conn);

static int iscsi_iter_destroy_flashnode_conn_fn(struct device *dev, void *data)
{
        if (!iscsi_is_flashnode_conn_dev(dev, NULL))
                return 0;

        return iscsi_destroy_flashnode_conn(iscsi_dev_to_flash_conn(dev));
}

/**
 * iscsi_destroy_flashnode_sess - destory flashnode session entry
 * @fnode_sess: pointer to flashnode session entry to be destroyed
 *
 * Deletes the flashnode session entry and all children flashnode connection
 * entries from sysfs
 */
void iscsi_destroy_flashnode_sess(struct iscsi_bus_flash_session *fnode_sess)
{
        int err;

        err = device_for_each_child(&fnode_sess->dev, NULL,
                                    iscsi_iter_destroy_flashnode_conn_fn);
        if (err)
                pr_err("Could not delete all connections for %s. Error %d.\n",
                       fnode_sess->dev.kobj.name, err);

        device_unregister(&fnode_sess->dev);
}
EXPORT_SYMBOL_GPL(iscsi_destroy_flashnode_sess);

static int iscsi_iter_destroy_flashnode_fn(struct device *dev, void *data)
{
        if (!iscsi_flashnode_bus_match(dev, NULL))
                return 0;

        iscsi_destroy_flashnode_sess(iscsi_dev_to_flash_session(dev));
        return 0;
}

/**
 * iscsi_destroy_all_flashnode - destory all flashnode session entries
 * @shost: pointer to host data
 *
 * Destroys all the flashnode session entries and all corresponding children
 * flashnode connection entries from sysfs
 */
void iscsi_destroy_all_flashnode(struct Scsi_Host *shost)
{
        device_for_each_child(&shost->shost_gendev, NULL,
                              iscsi_iter_destroy_flashnode_fn);
}
EXPORT_SYMBOL_GPL(iscsi_destroy_all_flashnode);

/*
 * BSG support
 */
/**
 * iscsi_bsg_host_dispatch - Dispatch command to LLD.
 * @job: bsg job to be processed
 */
static int iscsi_bsg_host_dispatch(struct bsg_job *job)
{
        struct Scsi_Host *shost = iscsi_job_to_shost(job);
        struct iscsi_bsg_request *req = job->request;
        struct iscsi_bsg_reply *reply = job->reply;
        struct iscsi_internal *i = to_iscsi_internal(shost->transportt);
        int cmdlen = sizeof(uint32_t);  /* start with length of msgcode */
        int ret;

        /* check if we have the msgcode value at least */
        if (job->request_len < sizeof(uint32_t)) {
                ret = -ENOMSG;
                goto fail_host_msg;
        }

        /* Validate the host command */
        switch (req->msgcode) {
        case ISCSI_BSG_HST_VENDOR:
                cmdlen += sizeof(struct iscsi_bsg_host_vendor);
                if ((shost->hostt->vendor_id == 0L) ||
                    (req->rqst_data.h_vendor.vendor_id !=
                        shost->hostt->vendor_id)) {
                        ret = -ESRCH;
                        goto fail_host_msg;
                }
                break;
        default:
                ret = -EBADR;
                goto fail_host_msg;
        }

        /* check if we really have all the request data needed */
        if (job->request_len < cmdlen) {
                ret = -ENOMSG;
                goto fail_host_msg;
        }

        ret = i->iscsi_transport->bsg_request(job);
        if (!ret)
                return 0;

fail_host_msg:
        /* return the errno failure code as the only status */
        BUG_ON(job->reply_len < sizeof(uint32_t));
        reply->reply_payload_rcv_len = 0;
        reply->result = ret;
        job->reply_len = sizeof(uint32_t);
        bsg_job_done(job, ret, 0);
        return 0;
}

/**
 * iscsi_bsg_host_add - Create and add the bsg hooks to receive requests
 * @shost: shost for iscsi_host
 * @ihost: iscsi_cls_host adding the structures to
 */
static int
iscsi_bsg_host_add(struct Scsi_Host *shost, struct iscsi_cls_host *ihost)
{
        struct device *dev = &shost->shost_gendev;
        struct iscsi_internal *i = to_iscsi_internal(shost->transportt);
        struct request_queue *q;
        char bsg_name[20];
        int ret;

        if (!i->iscsi_transport->bsg_request)
                return -ENOTSUPP;

        snprintf(bsg_name, sizeof(bsg_name), "iscsi_host%d", shost->host_no);

        q = __scsi_alloc_queue(shost, bsg_request_fn);
        if (!q)
                return -ENOMEM;

        ret = bsg_setup_queue(dev, q, bsg_name, iscsi_bsg_host_dispatch, 0);
        if (ret) {
                shost_printk(KERN_ERR, shost, "bsg interface failed to "
                             "initialize - no request queue\n");
                blk_cleanup_queue(q);
                return ret;
        }

        ihost->bsg_q = q;
        return 0;
}

static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
                            struct device *cdev)
{
        struct Scsi_Host *shost = dev_to_shost(dev);
        struct iscsi_cls_host *ihost = shost->shost_data;

        memset(ihost, 0, sizeof(*ihost));
        atomic_set(&ihost->nr_scans, 0);
        mutex_init(&ihost->mutex);

        iscsi_bsg_host_add(shost, ihost);
        /* ignore any bsg add error - we just can't do sgio */

        return 0;
}

static int iscsi_remove_host(struct transport_container *tc,
                             struct device *dev, struct device *cdev)
{
        struct Scsi_Host *shost = dev_to_shost(dev);
        struct iscsi_cls_host *ihost = shost->shost_data;

        if (ihost->bsg_q) {
                bsg_unregister_queue(ihost->bsg_q);
                blk_cleanup_queue(ihost->bsg_q);
        }
        return 0;
}

static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
                               "iscsi_host",
                               iscsi_setup_host,
                               iscsi_remove_host,
                               NULL);

static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
                               "iscsi_session",
                               NULL,
                               NULL,
                               NULL);

static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
                               "iscsi_connection",
                               NULL,
                               NULL,
                               NULL);

static struct sock *nls;
static DEFINE_MUTEX(rx_queue_mutex);

static LIST_HEAD(sesslist);
static DEFINE_SPINLOCK(sesslock);
static LIST_HEAD(connlist);
static DEFINE_SPINLOCK(connlock);

static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
{
        struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
        return sess->sid;
}

/*
 * Returns the matching session to a given sid
 */
static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
{
        unsigned long flags;
        struct iscsi_cls_session *sess;

        spin_lock_irqsave(&sesslock, flags);
        list_for_each_entry(sess, &sesslist, sess_list) {
                if (sess->sid == sid) {
                        spin_unlock_irqrestore(&sesslock, flags);
                        return sess;
                }
        }
        spin_unlock_irqrestore(&sesslock, flags);
        return NULL;
}

/*
 * Returns the matching connection to a given sid / cid tuple
 */
static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
{
        unsigned long flags;
        struct iscsi_cls_conn *conn;

        spin_lock_irqsave(&connlock, flags);
        list_for_each_entry(conn, &connlist, conn_list) {
                if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
                        spin_unlock_irqrestore(&connlock, flags);
                        return conn;
                }
        }
        spin_unlock_irqrestore(&connlock, flags);
        return NULL;
}

/*
 * The following functions can be used by LLDs that allocate
 * their own scsi_hosts or by software iscsi LLDs
 */
static struct {
        int value;
        char *name;
} iscsi_session_state_names[] = {
        { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
        { ISCSI_SESSION_FAILED,         "FAILED" },
        { ISCSI_SESSION_FREE,           "FREE" },
};

static const char *iscsi_session_state_name(int state)
{
        int i;
        char *name = NULL;

        for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
                if (iscsi_session_state_names[i].value == state) {
                        name = iscsi_session_state_names[i].name;
                        break;
                }
        }
        return name;
}

int iscsi_session_chkready(struct iscsi_cls_session *session)
{
        unsigned long flags;
        int err;

        spin_lock_irqsave(&session->lock, flags);
        switch (session->state) {
        case ISCSI_SESSION_LOGGED_IN:
                err = 0;
                break;
        case ISCSI_SESSION_FAILED:
                err = DID_IMM_RETRY << 16;
                break;
        case ISCSI_SESSION_FREE:
                err = DID_TRANSPORT_FAILFAST << 16;
                break;
        default:
                err = DID_NO_CONNECT << 16;
                break;
        }
        spin_unlock_irqrestore(&session->lock, flags);
        return err;
}
EXPORT_SYMBOL_GPL(iscsi_session_chkready);

int iscsi_is_session_online(struct iscsi_cls_session *session)
{
        unsigned long flags;
        int ret = 0;

        spin_lock_irqsave(&session->lock, flags);
        if (session->state == ISCSI_SESSION_LOGGED_IN)
                ret = 1;
        spin_unlock_irqrestore(&session->lock, flags);
        return ret;
}
EXPORT_SYMBOL_GPL(iscsi_is_session_online);

static void iscsi_session_release(struct device *dev)
{
        struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
        struct Scsi_Host *shost;

        shost = iscsi_session_to_shost(session);
        scsi_host_put(shost);
        ISCSI_DBG_TRANS_SESSION(session, "Completing session release\n");
        kfree(session);
}

int iscsi_is_session_dev(const struct device *dev)
{
        return dev->release == iscsi_session_release;
}
EXPORT_SYMBOL_GPL(iscsi_is_session_dev);

static int iscsi_iter_session_fn(struct device *dev, void *data)
{
        void (* fn) (struct iscsi_cls_session *) = data;

        if (!iscsi_is_session_dev(dev))
                return 0;
        fn(iscsi_dev_to_session(dev));
        return 0;
}

void iscsi_host_for_each_session(struct Scsi_Host *shost,
                                 void (*fn)(struct iscsi_cls_session *))
{
        device_for_each_child(&shost->shost_gendev, fn,
                              iscsi_iter_session_fn);
}
EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);

/**
 * iscsi_scan_finished - helper to report when running scans are done
 * @shost: scsi host
 * @time: scan run time
 *
 * This function can be used by drives like qla4xxx to report to the scsi
 * layer when the scans it kicked off at module load time are done.
 */
int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
{
        struct iscsi_cls_host *ihost = shost->shost_data;
        /*
         * qla4xxx will have kicked off some session unblocks before calling
         * scsi_scan_host, so just wait for them to complete.
         */
        return !atomic_read(&ihost->nr_scans);
}
EXPORT_SYMBOL_GPL(iscsi_scan_finished);

struct iscsi_scan_data {
        unsigned int channel;
        unsigned int id;
        unsigned int lun;
};

static int iscsi_user_scan_session(struct device *dev, void *data)
{
        struct iscsi_scan_data *scan_data = data;
        struct iscsi_cls_session *session;
        struct Scsi_Host *shost;
        struct iscsi_cls_host *ihost;
        unsigned long flags;
        unsigned int id;

        if (!iscsi_is_session_dev(dev))
                return 0;

        session = iscsi_dev_to_session(dev);

        ISCSI_DBG_TRANS_SESSION(session, "Scanning session\n");

        shost = iscsi_session_to_shost(session);
        ihost = shost->shost_data;

        mutex_lock(&ihost->mutex);
        spin_lock_irqsave(&session->lock, flags);
        if (session->state != ISCSI_SESSION_LOGGED_IN) {
                spin_unlock_irqrestore(&session->lock, flags);
                goto user_scan_exit;
        }
        id = session->target_id;
        spin_unlock_irqrestore(&session->lock, flags);

        if (id != ISCSI_MAX_TARGET) {
                if ((scan_data->channel == SCAN_WILD_CARD ||
                     scan_data->channel == 0) &&
                    (scan_data->id == SCAN_WILD_CARD ||
                     scan_data->id == id))
                        scsi_scan_target(&session->dev, 0, id,
                                         scan_data->lun, 1);
        }

user_scan_exit:
        mutex_unlock(&ihost->mutex);
        ISCSI_DBG_TRANS_SESSION(session, "Completed session scan\n");
        return 0;
}

static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
                           uint id, uint lun)
{
        struct iscsi_scan_data scan_data;

        scan_data.channel = channel;
        scan_data.id = id;
        scan_data.lun = lun;

        return device_for_each_child(&shost->shost_gendev, &scan_data,
                                     iscsi_user_scan_session);
}

static void iscsi_scan_session(struct work_struct *work)
{
        struct iscsi_cls_session *session =
                        container_of(work, struct iscsi_cls_session, scan_work);
        struct Scsi_Host *shost = iscsi_session_to_shost(session);
        struct iscsi_cls_host *ihost = shost->shost_data;
        struct iscsi_scan_data scan_data;

        scan_data.channel = 0;
        scan_data.id = SCAN_WILD_CARD;
        scan_data.lun = SCAN_WILD_CARD;

        iscsi_user_scan_session(&session->dev, &scan_data);
        atomic_dec(&ihost->nr_scans);
}

/**
 * iscsi_block_scsi_eh - block scsi eh until session state has transistioned
 * @cmd: scsi cmd passed to scsi eh handler
 *
 * If the session is down this function will wait for the recovery
 * timer to fire or for the session to be logged back in. If the
 * recovery timer fires then FAST_IO_FAIL is returned. The caller
 * should pass this error value to the scsi eh.
 */
int iscsi_block_scsi_eh(struct scsi_cmnd *cmd)
{
        struct iscsi_cls_session *session =
                        starget_to_session(scsi_target(cmd->device));
        unsigned long flags;
        int ret = 0;

        spin_lock_irqsave(&session->lock, flags);
        while (session->state != ISCSI_SESSION_LOGGED_IN) {
                if (session->state == ISCSI_SESSION_FREE) {
                        ret = FAST_IO_FAIL;
                        break;
                }
                spin_unlock_irqrestore(&session->lock, flags);
                msleep(1000);
                spin_lock_irqsave(&session->lock, flags);
        }
        spin_unlock_irqrestore(&session->lock, flags);
        return ret;
}
EXPORT_SYMBOL_GPL(iscsi_block_scsi_eh);

static void session_recovery_timedout(struct work_struct *work)
{
        struct iscsi_cls_session *session =
                container_of(work, struct iscsi_cls_session,
                             recovery_work.work);
        unsigned long flags;

        iscsi_cls_session_printk(KERN_INFO, session,
                                 "session recovery timed out after %d secs\n",
                                 session->recovery_tmo);

        spin_lock_irqsave(&session->lock, flags);
        switch (session->state) {
        case ISCSI_SESSION_FAILED:
                session->state = ISCSI_SESSION_FREE;
                break;
        case ISCSI_SESSION_LOGGED_IN:
        case ISCSI_SESSION_FREE:
                /* we raced with the unblock's flush */
                spin_unlock_irqrestore(&session->lock, flags);
                return;
        }
        spin_unlock_irqrestore(&session->lock, flags);

        if (session->transport->session_recovery_timedout)
                session->transport->session_recovery_timedout(session);

        ISCSI_DBG_TRANS_SESSION(session, "Unblocking SCSI target\n");
        scsi_target_unblock(&session->dev, SDEV_TRANSPORT_OFFLINE);
        ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking SCSI target\n");
}

static void __iscsi_unblock_session(struct work_struct *work)
{
        struct iscsi_cls_session *session =
                        container_of(work, struct iscsi_cls_session,
                                     unblock_work);
        struct Scsi_Host *shost = iscsi_session_to_shost(session);
        struct iscsi_cls_host *ihost = shost->shost_data;
        unsigned long flags;

        ISCSI_DBG_TRANS_SESSION(session, "Unblocking session\n");
        /*
         * The recovery and unblock work get run from the same workqueue,
         * so try to cancel it if it was going to run after this unblock.
         */
        cancel_delayed_work(&session->recovery_work);
        spin_lock_irqsave(&session->lock, flags);
        session->state = ISCSI_SESSION_LOGGED_IN;
        spin_unlock_irqrestore(&session->lock, flags);
        /* start IO */
        scsi_target_unblock(&session->dev, SDEV_RUNNING);
        /*
         * Only do kernel scanning if the driver is properly hooked into
         * the async scanning code (drivers like iscsi_tcp do login and
         * scanning from userspace).
         */
        if (shost->hostt->scan_finished) {
                if (scsi_queue_work(shost, &session->scan_work))
                        atomic_inc(&ihost->nr_scans);
        }
        ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
}

/**
 * iscsi_unblock_session - set a session as logged in and start IO.
 * @session: iscsi session
 *
 * Mark a session as ready to accept IO.
 */
void iscsi_unblock_session(struct iscsi_cls_session *session)
{
        queue_work(iscsi_eh_timer_workq, &session->unblock_work);
        /*
         * make sure all the events have completed before tell the driver
         * it is safe
         */
        flush_workqueue(iscsi_eh_timer_workq);
}
EXPORT_SYMBOL_GPL(iscsi_unblock_session);

static void __iscsi_block_session(struct work_struct *work)
{
        struct iscsi_cls_session *session =
                        container_of(work, struct iscsi_cls_session,
                                     block_work);
        unsigned long flags;

        ISCSI_DBG_TRANS_SESSION(session, "Blocking session\n");
        spin_lock_irqsave(&session->lock, flags);
        session->state = ISCSI_SESSION_FAILED;
        spin_unlock_irqrestore(&session->lock, flags);
        scsi_target_block(&session->dev);
        ISCSI_DBG_TRANS_SESSION(session, "Completed SCSI target blocking\n");
        if (session->recovery_tmo >= 0)
                queue_delayed_work(iscsi_eh_timer_workq,
                                   &session->recovery_work,
                                   session->recovery_tmo * HZ);
}

void iscsi_block_session(struct iscsi_cls_session *session)
{
        queue_work(iscsi_eh_timer_workq, &session->block_work);
}
EXPORT_SYMBOL_GPL(iscsi_block_session);

static void __iscsi_unbind_session(struct work_struct *work)
{
        struct iscsi_cls_session *session =
                        container_of(work, struct iscsi_cls_session,
                                     unbind_work);
        struct Scsi_Host *shost = iscsi_session_to_shost(session);
        struct iscsi_cls_host *ihost = shost->shost_data;
        unsigned long flags;
        unsigned int target_id;

        ISCSI_DBG_TRANS_SESSION(session, "Unbinding session\n");

        /* Prevent new scans and make sure scanning is not in progress */
        mutex_lock(&ihost->mutex);
        spin_lock_irqsave(&session->lock, flags);
        if (session->target_id == ISCSI_MAX_TARGET) {
                spin_unlock_irqrestore(&session->lock, flags);
                mutex_unlock(&ihost->mutex);
                return;
        }

        target_id = session->target_id;
        session->target_id = ISCSI_MAX_TARGET;
        spin_unlock_irqrestore(&session->lock, flags);
        mutex_unlock(&ihost->mutex);

        if (session->ida_used)
                ida_simple_remove(&iscsi_sess_ida, target_id);

        scsi_remove_target(&session->dev);
        iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
        ISCSI_DBG_TRANS_SESSION(session, "Completed target removal\n");
}

struct iscsi_cls_session *
iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
                    int dd_size)
{
        struct iscsi_cls_session *session;

        session = kzalloc(sizeof(*session) + dd_size,
                          GFP_KERNEL);
        if (!session)
                return NULL;

        session->transport = transport;
        session->creator = -1;
        session->recovery_tmo = 120;
        session->state = ISCSI_SESSION_FREE;
        INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
        INIT_LIST_HEAD(&session->sess_list);
        INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
        INIT_WORK(&session->block_work, __iscsi_block_session);
        INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
        INIT_WORK(&session->scan_work, iscsi_scan_session);
        spin_lock_init(&session->lock);

        /* this is released in the dev's release function */
        scsi_host_get(shost);
        session->dev.parent = &shost->shost_gendev;
        session->dev.release = iscsi_session_release;
        device_initialize(&session->dev);
        if (dd_size)
                session->dd_data = &session[1];

        ISCSI_DBG_TRANS_SESSION(session, "Completed session allocation\n");
        return session;
}
EXPORT_SYMBOL_GPL(iscsi_alloc_session);

int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
{
        struct Scsi_Host *shost = iscsi_session_to_shost(session);
        struct iscsi_cls_host *ihost;
        unsigned long flags;
        int id = 0;
        int err;

        ihost = shost->shost_data;
        session->sid = atomic_add_return(1, &iscsi_session_nr);

        if (target_id == ISCSI_MAX_TARGET) {
                id = ida_simple_get(&iscsi_sess_ida, 0, 0, GFP_KERNEL);

                if (id < 0) {
                        iscsi_cls_session_printk(KERN_ERR, session,
                                        "Failure in Target ID Allocation\n");
                        return id;
                }
                session->target_id = (unsigned int)id;
                session->ida_used = true;
        } else
                session->target_id = target_id;

        dev_set_name(&session->dev, "session%u", session->sid);
        err = device_add(&session->dev);
        if (err) {
                iscsi_cls_session_printk(KERN_ERR, session,
                                         "could not register session's dev\n");
                goto release_ida;
        }
        transport_register_device(&session->dev);

        spin_lock_irqsave(&sesslock, flags);
        list_add(&session->sess_list, &sesslist);
        spin_unlock_irqrestore(&sesslock, flags);

        iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
        ISCSI_DBG_TRANS_SESSION(session, "Completed session adding\n");
        return 0;

release_ida:
        if (session->ida_used)
                ida_simple_remove(&iscsi_sess_ida, session->target_id);

        return err;
}
EXPORT_SYMBOL_GPL(iscsi_add_session);

/**
 * iscsi_create_session - create iscsi class session
 * @shost: scsi host
 * @transport: iscsi transport
 * @dd_size: private driver data size
 * @target_id: which target
 *
 * This can be called from a LLD or iscsi_transport.
 */
struct iscsi_cls_session *
iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
                     int dd_size, unsigned int target_id)
{
        struct iscsi_cls_session *session;

        session = iscsi_alloc_session(shost, transport, dd_size);
        if (!session)
                return NULL;

        if (iscsi_add_session(session, target_id)) {
                iscsi_free_session(session);
                return NULL;
        }
        return session;
}
EXPORT_SYMBOL_GPL(iscsi_create_session);

static void iscsi_conn_release(struct device *dev)
{
        struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
        struct device *parent = conn->dev.parent;

        ISCSI_DBG_TRANS_CONN(conn, "Releasing conn\n");
        kfree(conn);
        put_device(parent);
}

static int iscsi_is_conn_dev(const struct device *dev)
{
        return dev->release == iscsi_conn_release;
}

static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
{
        if (!iscsi_is_conn_dev(dev))
                return 0;
        return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
}

void iscsi_remove_session(struct iscsi_cls_session *session)
{
        struct Scsi_Host *shost = iscsi_session_to_shost(session);
        unsigned long flags;
        int err;

        ISCSI_DBG_TRANS_SESSION(session, "Removing session\n");

        spin_lock_irqsave(&sesslock, flags);
        list_del(&session->sess_list);
        spin_unlock_irqrestore(&sesslock, flags);

        /* make sure there are no blocks/unblocks queued */
        flush_workqueue(iscsi_eh_timer_workq);
        /* make sure the timedout callout is not running */
        if (!cancel_delayed_work(&session->recovery_work))
                flush_workqueue(iscsi_eh_timer_workq);
        /*
         * If we are blocked let commands flow again. The lld or iscsi
         * layer should set up the queuecommand to fail commands.
         * We assume that LLD will not be calling block/unblock while
         * removing the session.
         */
        spin_lock_irqsave(&session->lock, flags);
        session->state = ISCSI_SESSION_FREE;
        spin_unlock_irqrestore(&session->lock, flags);

        scsi_target_unblock(&session->dev, SDEV_TRANSPORT_OFFLINE);
        /* flush running scans then delete devices */
        scsi_flush_work(shost);
        __iscsi_unbind_session(&session->unbind_work);

        /* hw iscsi may not have removed all connections from session */
        err = device_for_each_child(&session->dev, NULL,
                                    iscsi_iter_destroy_conn_fn);
        if (err)
                iscsi_cls_session_printk(KERN_ERR, session,
                                         "Could not delete all connections "
                                         "for session. Error %d.\n", err);

        transport_unregister_device(&session->dev);

        ISCSI_DBG_TRANS_SESSION(session, "Completing session removal\n");
        device_del(&session->dev);
}
EXPORT_SYMBOL_GPL(iscsi_remove_session);

void iscsi_free_session(struct iscsi_cls_session *session)
{
        ISCSI_DBG_TRANS_SESSION(session, "Freeing session\n");
        iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
        put_device(&session->dev);
}
EXPORT_SYMBOL_GPL(iscsi_free_session);

/**
 * iscsi_destroy_session - destroy iscsi session
 * @session: iscsi_session
 *
 * Can be called by a LLD or iscsi_transport. There must not be
 * any running connections.
 */
int iscsi_destroy_session(struct iscsi_cls_session *session)
{
        iscsi_remove_session(session);
        ISCSI_DBG_TRANS_SESSION(session, "Completing session destruction\n");
        iscsi_free_session(session);
        return 0;
}
EXPORT_SYMBOL_GPL(iscsi_destroy_session);

/**
 * iscsi_create_conn - create iscsi class connection
 * @session: iscsi cls session
 * @dd_size: private driver data size
 * @cid: connection id
 *
 * This can be called from a LLD or iscsi_transport. The connection
 * is child of the session so cid must be unique for all connections
 * on the session.
 *
 * Since we do not support MCS, cid will normally be zero. In some cases
 * for software iscsi we could be trying to preallocate a connection struct
 * in which case there could be two connection structs and cid would be
 * non-zero.
 */
struct iscsi_cls_conn *
iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
{
        struct iscsi_transport *transport = session->transport;
        struct iscsi_cls_conn *conn;
        unsigned long flags;
        int err;

        conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
        if (!conn)
                return NULL;
        if (dd_size)
                conn->dd_data = &conn[1];

        mutex_init(&conn->ep_mutex);
        INIT_LIST_HEAD(&conn->conn_list);
        conn->transport = transport;
        conn->cid = cid;

        /* this is released in the dev's release function */
        if (!get_device(&session->dev))
                goto free_conn;

        dev_set_name(&conn->dev, "connection%d:%u", session->sid, cid);
        conn->dev.parent = &session->dev;
        conn->dev.release = iscsi_conn_release;
        err = device_register(&conn->dev);
        if (err) {
                iscsi_cls_session_printk(KERN_ERR, session, "could not "
                                         "register connection's dev\n");
                goto release_parent_ref;
        }
        transport_register_device(&conn->dev);

        spin_lock_irqsave(&connlock, flags);
        list_add(&conn->conn_list, &connlist);
        spin_unlock_irqrestore(&connlock, flags);

        ISCSI_DBG_TRANS_CONN(conn, "Completed conn creation\n");
        return conn;

release_parent_ref:
        put_device(&session->dev);
free_conn:
        kfree(conn);
        return NULL;
}

EXPORT_SYMBOL_GPL(iscsi_create_conn);

/**
 * iscsi_destroy_conn - destroy iscsi class connection
 * @conn: iscsi cls session
 *
 * This can be called from a LLD or iscsi_transport.
 */
int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
{
        unsigned long flags;

        spin_lock_irqsave(&connlock, flags);
        list_del(&conn->conn_list);
        spin_unlock_irqrestore(&connlock, flags);

        transport_unregister_device(&conn->dev);
        ISCSI_DBG_TRANS_CONN(conn, "Completing conn destruction\n");
        device_unregister(&conn->dev);
        return 0;
}
EXPORT_SYMBOL_GPL(iscsi_destroy_conn);

/*
 * iscsi interface functions
 */
static struct iscsi_internal *
iscsi_if_transport_lookup(struct iscsi_transport *tt)
{
        struct iscsi_internal *priv;
        unsigned long flags;

        spin_lock_irqsave(&iscsi_transport_lock, flags);
        list_for_each_entry(priv, &iscsi_transports, list) {
                if (tt == priv->iscsi_transport) {
                        spin_unlock_irqrestore(&iscsi_transport_lock, flags);
                        return priv;

                }
        }
        spin_unlock_irqrestore(&iscsi_transport_lock, flags);
        return NULL;
}

static int
iscsi_multicast_skb(struct sk_buff *skb, uint32_t group, gfp_t gfp)
{
        return nlmsg_multicast(nls, skb, 0, group, gfp);
}

int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
                   char *data, uint32_t data_size)
{
        struct nlmsghdr *nlh;
        struct sk_buff *skb;
        struct iscsi_uevent *ev;
        char *pdu;
        struct iscsi_internal *priv;
        int len = nlmsg_total_size(sizeof(*ev) + sizeof(struct iscsi_hdr) +
                                   data_size);

        priv = iscsi_if_transport_lookup(conn->transport);
        if (!priv)
                return -EINVAL;

        skb = alloc_skb(len, GFP_ATOMIC);
        if (!skb) {
                iscsi_conn_error_event(conn, ISCSI_ERR_CONN_FAILED);
                iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
                                      "control PDU: OOM\n");
                return -ENOMEM;
        }

        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
        ev = nlmsg_data(nlh);
        memset(ev, 0, sizeof(*ev));
        ev->transport_handle = iscsi_handle(conn->transport);
        ev->type = ISCSI_KEVENT_RECV_PDU;
        ev->r.recv_req.cid = conn->cid;
        ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
        pdu = (char*)ev + sizeof(*ev);
        memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
        memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);

        return iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
}
EXPORT_SYMBOL_GPL(iscsi_recv_pdu);

int iscsi_offload_mesg(struct Scsi_Host *shost,
                       struct iscsi_transport *transport, uint32_t type,
                       char *data, uint16_t data_size)
{
        struct nlmsghdr *nlh;
        struct sk_buff *skb;
        struct iscsi_uevent *ev;
        int len = nlmsg_total_size(sizeof(*ev) + data_size);

        skb = alloc_skb(len, GFP_ATOMIC);
        if (!skb) {
                printk(KERN_ERR "can not deliver iscsi offload message:OOM\n");
                return -ENOMEM;
        }

        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
        ev = nlmsg_data(nlh);
        memset(ev, 0, sizeof(*ev));
        ev->type = type;
        ev->transport_handle = iscsi_handle(transport);
        switch (type) {
        case ISCSI_KEVENT_PATH_REQ:
                ev->r.req_path.host_no = shost->host_no;
                break;
        case ISCSI_KEVENT_IF_DOWN:
                ev->r.notify_if_down.host_no = shost->host_no;
                break;
        }

        memcpy((char *)ev + sizeof(*ev), data, data_size);

        return iscsi_multicast_skb(skb, ISCSI_NL_GRP_UIP, GFP_ATOMIC);
}
EXPORT_SYMBOL_GPL(iscsi_offload_mesg);

void iscsi_conn_error_event(struct iscsi_cls_conn *conn, enum iscsi_err error)
{
        struct nlmsghdr *nlh;
        struct sk_buff  *skb;
        struct iscsi_uevent *ev;
        struct iscsi_internal *priv;
        int len = nlmsg_total_size(sizeof(*ev));

        priv = iscsi_if_transport_lookup(conn->transport);
        if (!priv)
                return;

        skb = alloc_skb(len, GFP_ATOMIC);
        if (!skb) {
                iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
                                      "conn error (%d)\n", error);
                return;
        }

        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
        ev = nlmsg_data(nlh);
        ev->transport_handle = iscsi_handle(conn->transport);
        ev->type = ISCSI_KEVENT_CONN_ERROR;
        ev->r.connerror.error = error;
        ev->r.connerror.cid = conn->cid;
        ev->r.connerror.sid = iscsi_conn_get_sid(conn);

        iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);

        iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
                              error);
}
EXPORT_SYMBOL_GPL(iscsi_conn_error_event);

void iscsi_conn_login_event(struct iscsi_cls_conn *conn,
                            enum iscsi_conn_state state)
{
        struct nlmsghdr *nlh;
        struct sk_buff  *skb;
        struct iscsi_uevent *ev;
        struct iscsi_internal *priv;
        int len = nlmsg_total_size(sizeof(*ev));

        priv = iscsi_if_transport_lookup(conn->transport);
        if (!priv)
                return;

        skb = alloc_skb(len, GFP_ATOMIC);
        if (!skb) {
                iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
                                      "conn login (%d)\n", state);
                return;
        }

        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
        ev = nlmsg_data(nlh);
        ev->transport_handle = iscsi_handle(conn->transport);
        ev->type = ISCSI_KEVENT_CONN_LOGIN_STATE;
        ev->r.conn_login.state = state;
        ev->r.conn_login.cid = conn->cid;
        ev->r.conn_login.sid = iscsi_conn_get_sid(conn);
        iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);

        iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn login (%d)\n",
                              state);
}
EXPORT_SYMBOL_GPL(iscsi_conn_login_event);

void iscsi_post_host_event(uint32_t host_no, struct iscsi_transport *transport,
                           enum iscsi_host_event_code code, uint32_t data_size,
                           uint8_t *data)
{
        struct nlmsghdr *nlh;
        struct sk_buff *skb;
        struct iscsi_uevent *ev;
        int len = nlmsg_total_size(sizeof(*ev) + data_size);

        skb = alloc_skb(len, GFP_NOIO);
        if (!skb) {
                printk(KERN_ERR "gracefully ignored host event (%d):%d OOM\n",
                       host_no, code);
                return;
        }

        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
        ev = nlmsg_data(nlh);
        ev->transport_handle = iscsi_handle(transport);
        ev->type = ISCSI_KEVENT_HOST_EVENT;
        ev->r.host_event.host_no = host_no;
        ev->r.host_event.code = code;
        ev->r.host_event.data_size = data_size;

        if (data_size)
                memcpy((char *)ev + sizeof(*ev), data, data_size);

        iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_NOIO);
}
EXPORT_SYMBOL_GPL(iscsi_post_host_event);

void iscsi_ping_comp_event(uint32_t host_no, struct iscsi_transport *transport,
                           uint32_t status, uint32_t pid, uint32_t data_size,
                           uint8_t *data)
{
        struct nlmsghdr *nlh;
        struct sk_buff *skb;
        struct iscsi_uevent *ev;
        int len = nlmsg_total_size(sizeof(*ev) + data_size);

        skb = alloc_skb(len, GFP_NOIO);
        if (!skb) {
                printk(KERN_ERR "gracefully ignored ping comp: OOM\n");
                return;
        }

        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
        ev = nlmsg_data(nlh);
        ev->transport_handle = iscsi_handle(transport);
        ev->type = ISCSI_KEVENT_PING_COMP;
        ev->r.ping_comp.host_no = host_no;
        ev->r.ping_comp.status = status;
        ev->r.ping_comp.pid = pid;
        ev->r.ping_comp.data_size = data_size;
        memcpy((char *)ev + sizeof(*ev), data, data_size);

        iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_NOIO);
}
EXPORT_SYMBOL_GPL(iscsi_ping_comp_event);

static int
iscsi_if_send_reply(uint32_t group, int seq, int type, int done, int multi,
                    void *payload, int size)
{
        struct sk_buff  *skb;
        struct nlmsghdr *nlh;
        int len = nlmsg_total_size(size);
        int flags = multi ? NLM_F_MULTI : 0;
        int t = done ? NLMSG_DONE : type;

        skb = alloc_skb(len, GFP_ATOMIC);
        if (!skb) {
                printk(KERN_ERR "Could not allocate skb to send reply.\n");
                return -ENOMEM;
        }

        nlh = __nlmsg_put(skb, 0, 0, t, (len - sizeof(*nlh)), 0);
        nlh->nlmsg_flags = flags;
        memcpy(nlmsg_data(nlh), payload, size);
        return iscsi_multicast_skb(skb, group, GFP_ATOMIC);
}

static int
iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
{
        struct iscsi_uevent *ev = nlmsg_data(nlh);
        struct iscsi_stats *stats;
        struct sk_buff *skbstat;
        struct iscsi_cls_conn *conn;
        struct nlmsghdr *nlhstat;
        struct iscsi_uevent *evstat;
        struct iscsi_internal *priv;
        int len = nlmsg_total_size(sizeof(*ev) +
                                   sizeof(struct iscsi_stats) +
                                   sizeof(struct iscsi_stats_custom) *
                                   ISCSI_STATS_CUSTOM_MAX);
        int err = 0;

        priv = iscsi_if_transport_lookup(transport);
        if (!priv)
                return -EINVAL;

        conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
        if (!conn)
                return -EEXIST;

        do {
                int actual_size;

                skbstat = alloc_skb(len, GFP_ATOMIC);
                if (!skbstat) {
                        iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
                                              "deliver stats: OOM\n");
                        return -ENOMEM;
                }

                nlhstat = __nlmsg_put(skbstat, 0, 0, 0,
                                      (len - sizeof(*nlhstat)), 0);
                evstat = nlmsg_data(nlhstat);
                memset(evstat, 0, sizeof(*evstat));
                evstat->transport_handle = iscsi_handle(conn->transport);
                evstat->type = nlh->nlmsg_type;
                evstat->u.get_stats.cid =
                        ev->u.get_stats.cid;
                evstat->u.get_stats.sid =
                        ev->u.get_stats.sid;
                stats = (struct iscsi_stats *)
                        ((char*)evstat + sizeof(*evstat));
                memset(stats, 0, sizeof(*stats));

                transport->get_stats(conn, stats);
                actual_size = nlmsg_total_size(sizeof(struct iscsi_uevent) +
                                               sizeof(struct iscsi_stats) +
                                               sizeof(struct iscsi_stats_custom) *
                                               stats->custom_length);
                actual_size -= sizeof(*nlhstat);
                actual_size = nlmsg_msg_size(actual_size);
                skb_trim(skbstat, NLMSG_ALIGN(actual_size));
                nlhstat->nlmsg_len = actual_size;

                err = iscsi_multicast_skb(skbstat, ISCSI_NL_GRP_ISCSID,
                                          GFP_ATOMIC);
        } while (err < 0 && err != -ECONNREFUSED);

        return err;
}

/**
 * iscsi_session_event - send session destr. completion event
 * @session: iscsi class session
 * @event: type of event
 */
int iscsi_session_event(struct iscsi_cls_session *session,
                        enum iscsi_uevent_e event)
{
        struct iscsi_internal *priv;
        struct Scsi_Host *shost;
        struct iscsi_uevent *ev;
        struct sk_buff  *skb;
        struct nlmsghdr *nlh;
        int rc, len = nlmsg_total_size(sizeof(*ev));

        priv = iscsi_if_transport_lookup(session->transport);
        if (!priv)
                return -EINVAL;
        shost = iscsi_session_to_shost(session);

        skb = alloc_skb(len, GFP_KERNEL);
        if (!skb) {
                iscsi_cls_session_printk(KERN_ERR, session,
                                         "Cannot notify userspace of session "
                                         "event %u\n", event);
                return -ENOMEM;
        }

        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
        ev = nlmsg_data(nlh);
        ev->transport_handle = iscsi_handle(session->transport);

        ev->type = event;
        switch (event) {
        case ISCSI_KEVENT_DESTROY_SESSION:
                ev->r.d_session.host_no = shost->host_no;
                ev->r.d_session.sid = session->sid;
                break;
        case ISCSI_KEVENT_CREATE_SESSION:
                ev->r.c_session_ret.host_no = shost->host_no;
                ev->r.c_session_ret.sid = session->sid;
                break;
        case ISCSI_KEVENT_UNBIND_SESSION:
                ev->r.unbind_session.host_no = shost->host_no;
                ev->r.unbind_session.sid = session->sid;
                break;
        default:
                iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
                                         "%u.\n", event);
                kfree_skb(skb);
                return -EINVAL;
        }

        /*
         * this will occur if the daemon is not up, so we just warn
         * the user and when the daemon is restarted it will handle it
         */
        rc = iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_KERNEL);
        if (rc == -ESRCH)
                iscsi_cls_session_printk(KERN_ERR, session,
                                         "Cannot notify userspace of session "
                                         "event %u. Check iscsi daemon\n",
                                         event);

        ISCSI_DBG_TRANS_SESSION(session, "Completed handling event %d rc %d\n",
                                event, rc);
        return rc;
}
EXPORT_SYMBOL_GPL(iscsi_session_event);

static int
iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
                        struct iscsi_uevent *ev, pid_t pid,
                        uint32_t initial_cmdsn, uint16_t cmds_max,
                        uint16_t queue_depth)
{
        struct iscsi_transport *transport = priv->iscsi_transport;
        struct iscsi_cls_session *session;
        struct Scsi_Host *shost;

        session = transport->create_session(ep, cmds_max, queue_depth,
                                            initial_cmdsn);
        if (!session)
                return -ENOMEM;

        session->creator = pid;
        shost = iscsi_session_to_shost(session);
        ev->r.c_session_ret.host_no = shost->host_no;
        ev->r.c_session_ret.sid = session->sid;
        ISCSI_DBG_TRANS_SESSION(session,
                                "Completed creating transport session\n");
        return 0;
}

static int
iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
{
        struct iscsi_cls_conn *conn;
        struct iscsi_cls_session *session;

        session = iscsi_session_lookup(ev->u.c_conn.sid);
        if (!session) {
                printk(KERN_ERR "iscsi: invalid session %d.\n",
                       ev->u.c_conn.sid);
                return -EINVAL;
        }

        conn = transport->create_conn(session, ev->u.c_conn.cid);
        if (!conn) {
                iscsi_cls_session_printk(KERN_ERR, session,
                                         "couldn't create a new connection.");
                return -ENOMEM;
        }

        ev->r.c_conn_ret.sid = session->sid;
        ev->r.c_conn_ret.cid = conn->cid;

        ISCSI_DBG_TRANS_CONN(conn, "Completed creating transport conn\n");
        return 0;
}

static int
iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
{
        struct iscsi_cls_conn *conn;

        conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
        if (!conn)
                return -EINVAL;

        ISCSI_DBG_TRANS_CONN(conn, "Destroying transport conn\n");
        if (transport->destroy_conn)
                transport->destroy_conn(conn);

        return 0;
}

static int
iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
{
        char *data = (char*)ev + sizeof(*ev);
        struct iscsi_cls_conn *conn;
        struct iscsi_cls_session *session;
        int err = 0, value = 0;

        session = iscsi_session_lookup(ev->u.set_param.sid);
        conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
        if (!conn || !session)
                return -EINVAL;

        switch (ev->u.set_param.param) {
        case ISCSI_PARAM_SESS_RECOVERY_TMO:
                sscanf(data, "%d", &value);
                session->recovery_tmo = value;
                break;
        default:
                err = transport->set_param(conn, ev->u.set_param.param,
                                           data, ev->u.set_param.len);
        }

        return err;
}

static int iscsi_if_ep_connect(struct iscsi_transport *transport,
                               struct iscsi_uevent *ev, int msg_type)
{
        struct iscsi_endpoint *ep;
        struct sockaddr *dst_addr;
        struct Scsi_Host *shost = NULL;
        int non_blocking, err = 0;

        if (!transport->ep_connect)
                return -EINVAL;

        if (msg_type == ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST) {
                shost = scsi_host_lookup(ev->u.ep_connect_through_host.host_no);
                if (!shost) {
                        printk(KERN_ERR "ep connect failed. Could not find "
                               "host no %u\n",
                               ev->u.ep_connect_through_host.host_no);
                        return -ENODEV;
                }
                non_blocking = ev->u.ep_connect_through_host.non_blocking;
        } else
                non_blocking = ev->u.ep_connect.non_blocking;

        dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
        ep = transport->ep_connect(shost, dst_addr, non_blocking);
        if (IS_ERR(ep)) {
                err = PTR_ERR(ep);
                goto release_host;
        }

        ev->r.ep_connect_ret.handle = ep->id;
release_host:
        if (shost)
                scsi_host_put(shost);
        return err;
}

static int iscsi_if_ep_disconnect(struct iscsi_transport *transport,
                                  u64 ep_handle)
{
        struct iscsi_cls_conn *conn;
        struct iscsi_endpoint *ep;

        if (!transport->ep_disconnect)
                return -EINVAL;

        ep = iscsi_lookup_endpoint(ep_handle);
        if (!ep)
                return -EINVAL;
        conn = ep->conn;
        if (conn) {
                mutex_lock(&conn->ep_mutex);
                conn->ep = NULL;
                mutex_unlock(&conn->ep_mutex);
        }

        transport->ep_disconnect(ep);
        return 0;
}

static int
iscsi_if_transport_ep(struct iscsi_transport *transport,
                      struct iscsi_uevent *ev, int msg_type)
{
        struct iscsi_endpoint *ep;
        int rc = 0;

        switch (msg_type) {
        case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
        case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
                rc = iscsi_if_ep_connect(transport, ev, msg_type);
                break;
        case ISCSI_UEVENT_TRANSPORT_EP_POLL:
                if (!transport->ep_poll)
                        return -EINVAL;

                ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
                if (!ep)
                        return -EINVAL;

                ev->r.retcode = transport->ep_poll(ep,
                                                   ev->u.ep_poll.timeout_ms);
                break;
        case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
                rc = iscsi_if_ep_disconnect(transport,
                                            ev->u.ep_disconnect.ep_handle);
                break;
        }
        return rc;
}

static int
iscsi_tgt_dscvr(struct iscsi_transport *transport,
                struct iscsi_uevent *ev)
{
        struct Scsi_Host *shost;
        struct sockaddr *dst_addr;
        int err;

        if (!transport->tgt_dscvr)
                return -EINVAL;

        shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
        if (!shost) {
                printk(KERN_ERR "target discovery could not find host no %u\n",
                       ev->u.tgt_dscvr.host_no);
                return -ENODEV;
        }


        dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
        err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
                                   ev->u.tgt_dscvr.enable, dst_addr);
        scsi_host_put(shost);
        return err;
}

static int
iscsi_set_host_param(struct iscsi_transport *transport,
                     struct iscsi_uevent *ev)
{
        char *data = (char*)ev + sizeof(*ev);
        struct Scsi_Host *shost;
        int err;

        if (!transport->set_host_param)
                return -ENOSYS;

        shost = scsi_host_lookup(ev->u.set_host_param.host_no);
        if (!shost) {
                printk(KERN_ERR "set_host_param could not find host no %u\n",
                       ev->u.set_host_param.host_no);
                return -ENODEV;
        }

        err = transport->set_host_param(shost, ev->u.set_host_param.param,
                                        data, ev->u.set_host_param.len);
        scsi_host_put(shost);
        return err;
}

static int
iscsi_set_path(struct iscsi_transport *transport, struct iscsi_uevent *ev)
{
        struct Scsi_Host *shost;
        struct iscsi_path *params;
        int err;

        if (!transport->set_path)
                return -ENOSYS;

        shost = scsi_host_lookup(ev->u.set_path.host_no);
        if (!shost) {
                printk(KERN_ERR "set path could not find host no %u\n",
                       ev->u.set_path.host_no);
                return -ENODEV;
        }

        params = (struct iscsi_path *)((char *)ev + sizeof(*ev));
        err = transport->set_path(shost, params);

        scsi_host_put(shost);
        return err;
}

static int
iscsi_set_iface_params(struct iscsi_transport *transport,
                       struct iscsi_uevent *ev, uint32_t len)
{
        char *data = (char *)ev + sizeof(*ev);
        struct Scsi_Host *shost;
        int err;

        if (!transport->set_iface_param)
                return -ENOSYS;

        shost = scsi_host_lookup(ev->u.set_iface_params.host_no);
        if (!shost) {
                printk(KERN_ERR "set_iface_params could not find host no %u\n",
                       ev->u.set_iface_params.host_no);
                return -ENODEV;
        }

        err = transport->set_iface_param(shost, data, len);
        scsi_host_put(shost);
        return err;
}

static int
iscsi_send_ping(struct iscsi_transport *transport, struct iscsi_uevent *ev)
{
        struct Scsi_Host *shost;
        struct sockaddr *dst_addr;
        int err;

        if (!transport->send_ping)
                return -ENOSYS;

        shost = scsi_host_lookup(ev->u.iscsi_ping.host_no);
        if (!shost) {
                printk(KERN_ERR "iscsi_ping could not find host no %u\n",
                       ev->u.iscsi_ping.host_no);
                return -ENODEV;
        }

        dst_addr = (struct sockaddr *)((char *)ev + sizeof(*ev));
        err = transport->send_ping(shost, ev->u.iscsi_ping.iface_num,
                                   ev->u.iscsi_ping.iface_type,
                                   ev->u.iscsi_ping.payload_size,
                                   ev->u.iscsi_ping.pid,
                                   dst_addr);
        scsi_host_put(shost);
        return err;
}

static int
iscsi_get_chap(struct iscsi_transport *transport, struct nlmsghdr *nlh)
{
        struct iscsi_uevent *ev = nlmsg_data(nlh);
        struct Scsi_Host *shost = NULL;
        struct iscsi_chap_rec *chap_rec;
        struct iscsi_internal *priv;
        struct sk_buff *skbchap;
        struct nlmsghdr *nlhchap;
        struct iscsi_uevent *evchap;
        uint32_t chap_buf_size;
        int len, err = 0;
        char *buf;

        if (!transport->get_chap)
                return -EINVAL;

        priv = iscsi_if_transport_lookup(transport);
        if (!priv)
                return -EINVAL;

        chap_buf_size = (ev->u.get_chap.num_entries * sizeof(*chap_rec));
        len = nlmsg_total_size(sizeof(*ev) + chap_buf_size);

        shost = scsi_host_lookup(ev->u.get_chap.host_no);
        if (!shost) {
                printk(KERN_ERR "%s: failed. Cound not find host no %u\n",
                       __func__, ev->u.get_chap.host_no);
                return -ENODEV;
        }

        do {
                int actual_size;

                skbchap = alloc_skb(len, GFP_KERNEL);
                if (!skbchap) {
                        printk(KERN_ERR "can not deliver chap: OOM\n");
                        err = -ENOMEM;
                        goto exit_get_chap;
                }

                nlhchap = __nlmsg_put(skbchap, 0, 0, 0,
                                      (len - sizeof(*nlhchap)), 0);
                evchap = nlmsg_data(nlhchap);
                memset(evchap, 0, sizeof(*evchap));
                evchap->transport_handle = iscsi_handle(transport);
                evchap->type = nlh->nlmsg_type;
                evchap->u.get_chap.host_no = ev->u.get_chap.host_no;
                evchap->u.get_chap.chap_tbl_idx = ev->u.get_chap.chap_tbl_idx;
                evchap->u.get_chap.num_entries = ev->u.get_chap.num_entries;
                buf = (char *) ((char *)evchap + sizeof(*evchap));
                memset(buf, 0, chap_buf_size);

                err = transport->get_chap(shost, ev->u.get_chap.chap_tbl_idx,
                                    &evchap->u.get_chap.num_entries, buf);

                actual_size = nlmsg_total_size(sizeof(*ev) + chap_buf_size);
                skb_trim(skbchap, NLMSG_ALIGN(actual_size));
                nlhchap->nlmsg_len = actual_size;

                err = iscsi_multicast_skb(skbchap, ISCSI_NL_GRP_ISCSID,
                                          GFP_KERNEL);
        } while (err < 0 && err != -ECONNREFUSED);

exit_get_chap:
        scsi_host_put(shost);
        return err;
}

static int iscsi_delete_chap(struct iscsi_transport *transport,
                             struct iscsi_uevent *ev)
{
        struct Scsi_Host *shost;
        int err = 0;

        if (!transport->delete_chap)
                return -ENOSYS;

        shost = scsi_host_lookup(ev->u.delete_chap.host_no);
        if (!shost) {
                printk(KERN_ERR "%s could not find host no %u\n",
                       __func__, ev->u.delete_chap.host_no);
                return -ENODEV;
        }

        err = transport->delete_chap(shost, ev->u.delete_chap.chap_tbl_idx);
        scsi_host_put(shost);
        return err;
}

static const struct {
        enum iscsi_discovery_parent_type value;
        char                            *name;
} iscsi_discovery_parent_names[] = {
        {ISCSI_DISC_PARENT_UNKNOWN,     "Unknown" },
        {ISCSI_DISC_PARENT_SENDTGT,     "Sendtarget" },
        {ISCSI_DISC_PARENT_ISNS,        "isns" },
};

char *iscsi_get_discovery_parent_name(int parent_type)
{
        int i;
        char *state = "Unknown!";

        for (i = 0; i < ARRAY_SIZE(iscsi_discovery_parent_names); i++) {
                if (iscsi_discovery_parent_names[i].value & parent_type) {
                        state = iscsi_discovery_parent_names[i].name;
                        break;
                }
        }
        return state;
}
EXPORT_SYMBOL_GPL(iscsi_get_discovery_parent_name);

static int iscsi_set_flashnode_param(struct iscsi_transport *transport,
                                     struct iscsi_uevent *ev, uint32_t len)
{
        char *data = (char *)ev + sizeof(*ev);
        struct Scsi_Host *shost;
        struct iscsi_bus_flash_session *fnode_sess;
        struct iscsi_bus_flash_conn *fnode_conn;
        struct device *dev;
        uint32_t idx;
        int err = 0;

        if (!transport->set_flashnode_param) {
                err = -ENOSYS;
                goto exit_set_fnode;
        }

        shost = scsi_host_lookup(ev->u.set_flashnode.host_no);
        if (!shost) {
                pr_err("%s could not find host no %u\n",
                       __func__, ev->u.set_flashnode.host_no);
                err = -ENODEV;
                goto put_host;
        }

        idx = ev->u.set_flashnode.flashnode_idx;
        fnode_sess = iscsi_get_flashnode_by_index(shost, idx);
        if (!fnode_sess) {
                pr_err("%s could not find flashnode %u for host no %u\n",
                       __func__, idx, ev->u.set_flashnode.host_no);
                err = -ENODEV;
                goto put_host;
        }

        dev = iscsi_find_flashnode_conn(fnode_sess);
        if (!dev) {
                err = -ENODEV;
                goto put_sess;
        }

        fnode_conn = iscsi_dev_to_flash_conn(dev);
        err = transport->set_flashnode_param(fnode_sess, fnode_conn, data, len);
        put_device(dev);

put_sess:
        put_device(&fnode_sess->dev);

put_host:
        scsi_host_put(shost);

exit_set_fnode:
        return err;
}

static int iscsi_new_flashnode(struct iscsi_transport *transport,
                               struct iscsi_uevent *ev, uint32_t len)
{
        char *data = (char *)ev + sizeof(*ev);
        struct Scsi_Host *shost;
        int index;
        int err = 0;

        if (!transport->new_flashnode) {
                err = -ENOSYS;
                goto exit_new_fnode;
        }

        shost = scsi_host_lookup(ev->u.new_flashnode.host_no);
        if (!shost) {
                pr_err("%s could not find host no %u\n",
                       __func__, ev->u.new_flashnode.host_no);
                err = -ENODEV;
                goto put_host;
        }

        index = transport->new_flashnode(shost, data, len);

        if (index >= 0)
                ev->r.new_flashnode_ret.flashnode_idx = index;
        else
                err = -EIO;

put_host:
        scsi_host_put(shost);

exit_new_fnode:
        return err;
}

static int iscsi_del_flashnode(struct iscsi_transport *transport,
                               struct iscsi_uevent *ev)
{
        struct Scsi_Host *shost;
        struct iscsi_bus_flash_session *fnode_sess;
        uint32_t idx;
        int err = 0;

        if (!transport->del_flashnode) {
                err = -ENOSYS;
                goto exit_del_fnode;
        }

        shost = scsi_host_lookup(ev->u.del_flashnode.host_no);
        if (!shost) {
                pr_err("%s could not find host no %u\n",
                       __func__, ev->u.del_flashnode.host_no);
                err = -ENODEV;
                goto put_host;
        }

        idx = ev->u.del_flashnode.flashnode_idx;
        fnode_sess = iscsi_get_flashnode_by_index(shost, idx);
        if (!fnode_sess) {
                pr_err("%s could not find flashnode %u for host no %u\n",
                       __func__, idx, ev->u.del_flashnode.host_no);
                err = -ENODEV;
                goto put_host;
        }

        err = transport->del_flashnode(fnode_sess);
        put_device(&fnode_sess->dev);

put_host:
        scsi_host_put(shost);

exit_del_fnode:
        return err;
}

static int iscsi_login_flashnode(struct iscsi_transport *transport,
                                 struct iscsi_uevent *ev)
{
        struct Scsi_Host *shost;
        struct iscsi_bus_flash_session *fnode_sess;
        struct iscsi_bus_flash_conn *fnode_conn;
        struct device *dev;
        uint32_t idx;
        int err = 0;

        if (!transport->login_flashnode) {
                err = -ENOSYS;
                goto exit_login_fnode;
        }

        shost = scsi_host_lookup(ev->u.login_flashnode.host_no);
        if (!shost) {
                pr_err("%s could not find host no %u\n",
                       __func__, ev->u.login_flashnode.host_no);
                err = -ENODEV;
                goto put_host;
        }

        idx = ev->u.login_flashnode.flashnode_idx;
        fnode_sess = iscsi_get_flashnode_by_index(shost, idx);
        if (!fnode_sess) {
                pr_err("%s could not find flashnode %u for host no %u\n",
                       __func__, idx, ev->u.login_flashnode.host_no);
                err = -ENODEV;
                goto put_host;
        }

        dev = iscsi_find_flashnode_conn(fnode_sess);
        if (!dev) {
                err = -ENODEV;
                goto put_sess;
        }

        fnode_conn = iscsi_dev_to_flash_conn(dev);
        err = transport->login_flashnode(fnode_sess, fnode_conn);
        put_device(dev);

put_sess:
        put_device(&fnode_sess->dev);

put_host:
        scsi_host_put(shost);

exit_login_fnode:
        return err;
}

static int iscsi_logout_flashnode(struct iscsi_transport *transport,
                                  struct iscsi_uevent *ev)
{
        struct Scsi_Host *shost;
        struct iscsi_bus_flash_session *fnode_sess;
        struct iscsi_bus_flash_conn *fnode_conn;
        struct device *dev;
        uint32_t idx;
        int err = 0;

        if (!transport->logout_flashnode) {
                err = -ENOSYS;
                goto exit_logout_fnode;
        }

        shost = scsi_host_lookup(ev->u.logout_flashnode.host_no);
        if (!shost) {
                pr_err("%s could not find host no %u\n",
                       __func__, ev->u.logout_flashnode.host_no);
                err = -ENODEV;
                goto put_host;
        }

        idx = ev->u.logout_flashnode.flashnode_idx;
        fnode_sess = iscsi_get_flashnode_by_index(shost, idx);
        if (!fnode_sess) {
                pr_err("%s could not find flashnode %u for host no %u\n",
                       __func__, idx, ev->u.logout_flashnode.host_no);