x86: fix nmi_watchdog=2 on Pentium-D CPUs

[linux-2.6/openmoko-kernel/knife-kernel.git] / drivers / scsi / scsi_transport_fc.c

/*
 *  FiberChannel transport specific attributes exported to sysfs.
 *
 *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
 *
 *  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
 *
 *  ========
 *
 *  Copyright (C) 2004-2007   James Smart, Emulex Corporation
 *    Rewrite for host, target, device, and remote port attributes,
 *    statistics, and service functions...
 *    Add vports, etc
 *
 */
#include <linux/module.h>
#include <linux/init.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_fc.h>
#include <scsi/scsi_cmnd.h>
#include <linux/netlink.h>
#include <net/netlink.h>
#include <scsi/scsi_netlink_fc.h>
#include "scsi_priv.h"
#include "scsi_transport_fc_internal.h"

static int fc_queue_work(struct Scsi_Host *, struct work_struct *);
static void fc_vport_sched_delete(struct work_struct *work);

/*
 * This is a temporary carrier for creating a vport. It will eventually
 * be replaced  by a real message definition for sgio or netlink.
 *
 * fc_vport_identifiers: This set of data contains all elements
 * to uniquely identify and instantiate a FC virtual port.
 *
 * Notes:
 *   symbolic_name: The driver is to append the symbolic_name string data
 *      to the symbolic_node_name data that it generates by default.
 *      the resulting combination should then be registered with the switch.
 *      It is expected that things like Xen may stuff a VM title into
 *      this field.
 */
struct fc_vport_identifiers {
        u64 node_name;
        u64 port_name;
        u32 roles;
        bool disable;
        enum fc_port_type vport_type;   /* only FC_PORTTYPE_NPIV allowed */
        char symbolic_name[FC_VPORT_SYMBOLIC_NAMELEN];
};

static int fc_vport_create(struct Scsi_Host *shost, int channel,
        struct device *pdev, struct fc_vport_identifiers  *ids,
        struct fc_vport **vport);

/*
 * Redefine so that we can have same named attributes in the
 * sdev/starget/host objects.
 */
#define FC_CLASS_DEVICE_ATTR(_prefix,_name,_mode,_show,_store)          \
struct class_device_attribute class_device_attr_##_prefix##_##_name =   \
        __ATTR(_name,_mode,_show,_store)

#define fc_enum_name_search(title, table_type, table)                   \
static const char *get_fc_##title##_name(enum table_type table_key)     \
{                                                                       \
        int i;                                                          \
        char *name = NULL;                                              \
                                                                        \
        for (i = 0; i < ARRAY_SIZE(table); i++) {                       \
                if (table[i].value == table_key) {                      \
                        name = table[i].name;                           \
                        break;                                          \
                }                                                       \
        }                                                               \
        return name;                                                    \
}

#define fc_enum_name_match(title, table_type, table)                    \
static int get_fc_##title##_match(const char *table_key,                \
                enum table_type *value)                                 \
{                                                                       \
        int i;                                                          \
                                                                        \
        for (i = 0; i < ARRAY_SIZE(table); i++) {                       \
                if (strncmp(table_key, table[i].name,                   \
                                table[i].matchlen) == 0) {              \
                        *value = table[i].value;                        \
                        return 0; /* success */                         \
                }                                                       \
        }                                                               \
        return 1; /* failure */                                         \
}


/* Convert fc_port_type values to ascii string name */
static struct {
        enum fc_port_type       value;
        char                    *name;
} fc_port_type_names[] = {
        { FC_PORTTYPE_UNKNOWN,          "Unknown" },
        { FC_PORTTYPE_OTHER,            "Other" },
        { FC_PORTTYPE_NOTPRESENT,       "Not Present" },
        { FC_PORTTYPE_NPORT,    "NPort (fabric via point-to-point)" },
        { FC_PORTTYPE_NLPORT,   "NLPort (fabric via loop)" },
        { FC_PORTTYPE_LPORT,    "LPort (private loop)" },
        { FC_PORTTYPE_PTP,      "Point-To-Point (direct nport connection" },
        { FC_PORTTYPE_NPIV,             "NPIV VPORT" },
};
fc_enum_name_search(port_type, fc_port_type, fc_port_type_names)
#define FC_PORTTYPE_MAX_NAMELEN         50

/* Reuse fc_port_type enum function for vport_type */
#define get_fc_vport_type_name get_fc_port_type_name


/* Convert fc_host_event_code values to ascii string name */
static const struct {
        enum fc_host_event_code         value;
        char                            *name;
} fc_host_event_code_names[] = {
        { FCH_EVT_LIP,                  "lip" },
        { FCH_EVT_LINKUP,               "link_up" },
        { FCH_EVT_LINKDOWN,             "link_down" },
        { FCH_EVT_LIPRESET,             "lip_reset" },
        { FCH_EVT_RSCN,                 "rscn" },
        { FCH_EVT_ADAPTER_CHANGE,       "adapter_chg" },
        { FCH_EVT_PORT_UNKNOWN,         "port_unknown" },
        { FCH_EVT_PORT_ONLINE,          "port_online" },
        { FCH_EVT_PORT_OFFLINE,         "port_offline" },
        { FCH_EVT_PORT_FABRIC,          "port_fabric" },
        { FCH_EVT_LINK_UNKNOWN,         "link_unknown" },
        { FCH_EVT_VENDOR_UNIQUE,        "vendor_unique" },
};
fc_enum_name_search(host_event_code, fc_host_event_code,
                fc_host_event_code_names)
#define FC_HOST_EVENT_CODE_MAX_NAMELEN  30


/* Convert fc_port_state values to ascii string name */
static struct {
        enum fc_port_state      value;
        char                    *name;
} fc_port_state_names[] = {
        { FC_PORTSTATE_UNKNOWN,         "Unknown" },
        { FC_PORTSTATE_NOTPRESENT,      "Not Present" },
        { FC_PORTSTATE_ONLINE,          "Online" },
        { FC_PORTSTATE_OFFLINE,         "Offline" },
        { FC_PORTSTATE_BLOCKED,         "Blocked" },
        { FC_PORTSTATE_BYPASSED,        "Bypassed" },
        { FC_PORTSTATE_DIAGNOSTICS,     "Diagnostics" },
        { FC_PORTSTATE_LINKDOWN,        "Linkdown" },
        { FC_PORTSTATE_ERROR,           "Error" },
        { FC_PORTSTATE_LOOPBACK,        "Loopback" },
        { FC_PORTSTATE_DELETED,         "Deleted" },
};
fc_enum_name_search(port_state, fc_port_state, fc_port_state_names)
#define FC_PORTSTATE_MAX_NAMELEN        20


/* Convert fc_vport_state values to ascii string name */
static struct {
        enum fc_vport_state     value;
        char                    *name;
} fc_vport_state_names[] = {
        { FC_VPORT_UNKNOWN,             "Unknown" },
        { FC_VPORT_ACTIVE,              "Active" },
        { FC_VPORT_DISABLED,            "Disabled" },
        { FC_VPORT_LINKDOWN,            "Linkdown" },
        { FC_VPORT_INITIALIZING,        "Initializing" },
        { FC_VPORT_NO_FABRIC_SUPP,      "No Fabric Support" },
        { FC_VPORT_NO_FABRIC_RSCS,      "No Fabric Resources" },
        { FC_VPORT_FABRIC_LOGOUT,       "Fabric Logout" },
        { FC_VPORT_FABRIC_REJ_WWN,      "Fabric Rejected WWN" },
        { FC_VPORT_FAILED,              "VPort Failed" },
};
fc_enum_name_search(vport_state, fc_vport_state, fc_vport_state_names)
#define FC_VPORTSTATE_MAX_NAMELEN       24

/* Reuse fc_vport_state enum function for vport_last_state */
#define get_fc_vport_last_state_name get_fc_vport_state_name


/* Convert fc_tgtid_binding_type values to ascii string name */
static const struct {
        enum fc_tgtid_binding_type      value;
        char                            *name;
        int                             matchlen;
} fc_tgtid_binding_type_names[] = {
        { FC_TGTID_BIND_NONE, "none", 4 },
        { FC_TGTID_BIND_BY_WWPN, "wwpn (World Wide Port Name)", 4 },
        { FC_TGTID_BIND_BY_WWNN, "wwnn (World Wide Node Name)", 4 },
        { FC_TGTID_BIND_BY_ID, "port_id (FC Address)", 7 },
};
fc_enum_name_search(tgtid_bind_type, fc_tgtid_binding_type,
                fc_tgtid_binding_type_names)
fc_enum_name_match(tgtid_bind_type, fc_tgtid_binding_type,
                fc_tgtid_binding_type_names)
#define FC_BINDTYPE_MAX_NAMELEN 30


#define fc_bitfield_name_search(title, table)                   \
static ssize_t                                                  \
get_fc_##title##_names(u32 table_key, char *buf)                \
{                                                               \
        char *prefix = "";                                      \
        ssize_t len = 0;                                        \
        int i;                                                  \
                                                                \
        for (i = 0; i < ARRAY_SIZE(table); i++) {               \
                if (table[i].value & table_key) {               \
                        len += sprintf(buf + len, "%s%s",       \
                                prefix, table[i].name);         \
                        prefix = ", ";                          \
                }                                               \
        }                                                       \
        len += sprintf(buf + len, "\n");                        \
        return len;                                             \
}


/* Convert FC_COS bit values to ascii string name */
static const struct {
        u32                     value;
        char                    *name;
} fc_cos_names[] = {
        { FC_COS_CLASS1,        "Class 1" },
        { FC_COS_CLASS2,        "Class 2" },
        { FC_COS_CLASS3,        "Class 3" },
        { FC_COS_CLASS4,        "Class 4" },
        { FC_COS_CLASS6,        "Class 6" },
};
fc_bitfield_name_search(cos, fc_cos_names)


/* Convert FC_PORTSPEED bit values to ascii string name */
static const struct {
        u32                     value;
        char                    *name;
} fc_port_speed_names[] = {
        { FC_PORTSPEED_1GBIT,           "1 Gbit" },
        { FC_PORTSPEED_2GBIT,           "2 Gbit" },
        { FC_PORTSPEED_4GBIT,           "4 Gbit" },
        { FC_PORTSPEED_10GBIT,          "10 Gbit" },
        { FC_PORTSPEED_8GBIT,           "8 Gbit" },
        { FC_PORTSPEED_16GBIT,          "16 Gbit" },
        { FC_PORTSPEED_NOT_NEGOTIATED,  "Not Negotiated" },
};
fc_bitfield_name_search(port_speed, fc_port_speed_names)


static int
show_fc_fc4s (char *buf, u8 *fc4_list)
{
        int i, len=0;

        for (i = 0; i < FC_FC4_LIST_SIZE; i++, fc4_list++)
                len += sprintf(buf + len , "0x%02x ", *fc4_list);
        len += sprintf(buf + len, "\n");
        return len;
}


/* Convert FC_PORT_ROLE bit values to ascii string name */
static const struct {
        u32                     value;
        char                    *name;
} fc_port_role_names[] = {
        { FC_PORT_ROLE_FCP_TARGET,      "FCP Target" },
        { FC_PORT_ROLE_FCP_INITIATOR,   "FCP Initiator" },
        { FC_PORT_ROLE_IP_PORT,         "IP Port" },
};
fc_bitfield_name_search(port_roles, fc_port_role_names)

/*
 * Define roles that are specific to port_id. Values are relative to ROLE_MASK.
 */
#define FC_WELLKNOWN_PORTID_MASK        0xfffff0
#define FC_WELLKNOWN_ROLE_MASK          0x00000f
#define FC_FPORT_PORTID                 0x00000e
#define FC_FABCTLR_PORTID               0x00000d
#define FC_DIRSRVR_PORTID               0x00000c
#define FC_TIMESRVR_PORTID              0x00000b
#define FC_MGMTSRVR_PORTID              0x00000a


static void fc_timeout_deleted_rport(struct work_struct *work);
static void fc_timeout_fail_rport_io(struct work_struct *work);
static void fc_scsi_scan_rport(struct work_struct *work);

/*
 * Attribute counts pre object type...
 * Increase these values if you add attributes
 */
#define FC_STARGET_NUM_ATTRS    3
#define FC_RPORT_NUM_ATTRS      10
#define FC_VPORT_NUM_ATTRS      9
#define FC_HOST_NUM_ATTRS       21

struct fc_internal {
        struct scsi_transport_template t;
        struct fc_function_template *f;

        /*
         * For attributes : each object has :
         *   An array of the actual attributes structures
         *   An array of null-terminated pointers to the attribute
         *     structures - used for mid-layer interaction.
         *
         * The attribute containers for the starget and host are are
         * part of the midlayer. As the remote port is specific to the
         * fc transport, we must provide the attribute container.
         */
        struct class_device_attribute private_starget_attrs[
                                                        FC_STARGET_NUM_ATTRS];
        struct class_device_attribute *starget_attrs[FC_STARGET_NUM_ATTRS + 1];

        struct class_device_attribute private_host_attrs[FC_HOST_NUM_ATTRS];
        struct class_device_attribute *host_attrs[FC_HOST_NUM_ATTRS + 1];

        struct transport_container rport_attr_cont;
        struct class_device_attribute private_rport_attrs[FC_RPORT_NUM_ATTRS];
        struct class_device_attribute *rport_attrs[FC_RPORT_NUM_ATTRS + 1];

        struct transport_container vport_attr_cont;
        struct class_device_attribute private_vport_attrs[FC_VPORT_NUM_ATTRS];
        struct class_device_attribute *vport_attrs[FC_VPORT_NUM_ATTRS + 1];
};

#define to_fc_internal(tmpl)    container_of(tmpl, struct fc_internal, t)

static int fc_target_setup(struct transport_container *tc, struct device *dev,
                           struct class_device *cdev)
{
        struct scsi_target *starget = to_scsi_target(dev);
        struct fc_rport *rport = starget_to_rport(starget);

        /*
         * if parent is remote port, use values from remote port.
         * Otherwise, this host uses the fc_transport, but not the
         * remote port interface. As such, initialize to known non-values.
         */
        if (rport) {
                fc_starget_node_name(starget) = rport->node_name;
                fc_starget_port_name(starget) = rport->port_name;
                fc_starget_port_id(starget) = rport->port_id;
        } else {
                fc_starget_node_name(starget) = -1;
                fc_starget_port_name(starget) = -1;
                fc_starget_port_id(starget) = -1;
        }

        return 0;
}

static DECLARE_TRANSPORT_CLASS(fc_transport_class,
                               "fc_transport",
                               fc_target_setup,
                               NULL,
                               NULL);

static int fc_host_setup(struct transport_container *tc, struct device *dev,
                         struct class_device *cdev)
{
        struct Scsi_Host *shost = dev_to_shost(dev);
        struct fc_host_attrs *fc_host = shost_to_fc_host(shost);

        /*
         * Set default values easily detected by the midlayer as
         * failure cases.  The scsi lldd is responsible for initializing
         * all transport attributes to valid values per host.
         */
        fc_host->node_name = -1;
        fc_host->port_name = -1;
        fc_host->permanent_port_name = -1;
        fc_host->supported_classes = FC_COS_UNSPECIFIED;
        memset(fc_host->supported_fc4s, 0,
                sizeof(fc_host->supported_fc4s));
        fc_host->supported_speeds = FC_PORTSPEED_UNKNOWN;
        fc_host->maxframe_size = -1;
        fc_host->max_npiv_vports = 0;
        memset(fc_host->serial_number, 0,
                sizeof(fc_host->serial_number));

        fc_host->port_id = -1;
        fc_host->port_type = FC_PORTTYPE_UNKNOWN;
        fc_host->port_state = FC_PORTSTATE_UNKNOWN;
        memset(fc_host->active_fc4s, 0,
                sizeof(fc_host->active_fc4s));
        fc_host->speed = FC_PORTSPEED_UNKNOWN;
        fc_host->fabric_name = -1;
        memset(fc_host->symbolic_name, 0, sizeof(fc_host->symbolic_name));
        memset(fc_host->system_hostname, 0, sizeof(fc_host->system_hostname));

        fc_host->tgtid_bind_type = FC_TGTID_BIND_BY_WWPN;

        INIT_LIST_HEAD(&fc_host->rports);
        INIT_LIST_HEAD(&fc_host->rport_bindings);
        INIT_LIST_HEAD(&fc_host->vports);
        fc_host->next_rport_number = 0;
        fc_host->next_target_id = 0;
        fc_host->next_vport_number = 0;
        fc_host->npiv_vports_inuse = 0;

        snprintf(fc_host->work_q_name, KOBJ_NAME_LEN, "fc_wq_%d",
                shost->host_no);
        fc_host->work_q = create_singlethread_workqueue(
                                        fc_host->work_q_name);
        if (!fc_host->work_q)
                return -ENOMEM;

        snprintf(fc_host->devloss_work_q_name, KOBJ_NAME_LEN, "fc_dl_%d",
                shost->host_no);
        fc_host->devloss_work_q = create_singlethread_workqueue(
                                        fc_host->devloss_work_q_name);
        if (!fc_host->devloss_work_q) {
                destroy_workqueue(fc_host->work_q);
                fc_host->work_q = NULL;
                return -ENOMEM;
        }

        return 0;
}

static DECLARE_TRANSPORT_CLASS(fc_host_class,
                               "fc_host",
                               fc_host_setup,
                               NULL,
                               NULL);

/*
 * Setup and Remove actions for remote ports are handled
 * in the service functions below.
 */
static DECLARE_TRANSPORT_CLASS(fc_rport_class,
                               "fc_remote_ports",
                               NULL,
                               NULL,
                               NULL);

/*
 * Setup and Remove actions for virtual ports are handled
 * in the service functions below.
 */
static DECLARE_TRANSPORT_CLASS(fc_vport_class,
                               "fc_vports",
                               NULL,
                               NULL,
                               NULL);

/*
 * Module Parameters
 */

/*
 * dev_loss_tmo: the default number of seconds that the FC transport
 *   should insulate the loss of a remote port.
 *   The maximum will be capped by the value of SCSI_DEVICE_BLOCK_MAX_TIMEOUT.
 */
static unsigned int fc_dev_loss_tmo = 60;               /* seconds */

module_param_named(dev_loss_tmo, fc_dev_loss_tmo, uint, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(dev_loss_tmo,
                 "Maximum number of seconds that the FC transport should"
                 " insulate the loss of a remote port. Once this value is"
                 " exceeded, the scsi target is removed. Value should be"
                 " between 1 and SCSI_DEVICE_BLOCK_MAX_TIMEOUT.");

/*
 * Netlink Infrastructure
 */

static atomic_t fc_event_seq;

/**
 * fc_get_event_number - Obtain the next sequential FC event number
 *
 * Notes:
 *   We could have inlined this, but it would have required fc_event_seq to
 *   be exposed. For now, live with the subroutine call.
 *   Atomic used to avoid lock/unlock...
 */
u32
fc_get_event_number(void)
{
        return atomic_add_return(1, &fc_event_seq);
}
EXPORT_SYMBOL(fc_get_event_number);


/**
 * fc_host_post_event - called to post an even on an fc_host.
 * @shost:              host the event occurred on
 * @event_number:       fc event number obtained from get_fc_event_number()
 * @event_code:         fc_host event being posted
 * @event_data:         32bits of data for the event being posted
 *
 * Notes:
 *      This routine assumes no locks are held on entry.
 */
void
fc_host_post_event(struct Scsi_Host *shost, u32 event_number,
                enum fc_host_event_code event_code, u32 event_data)
{
        struct sk_buff *skb;
        struct nlmsghdr *nlh;
        struct fc_nl_event *event;
        const char *name;
        u32 len, skblen;
        int err;

        if (!scsi_nl_sock) {
                err = -ENOENT;
                goto send_fail;
        }

        len = FC_NL_MSGALIGN(sizeof(*event));
        skblen = NLMSG_SPACE(len);

        skb = alloc_skb(skblen, GFP_KERNEL);
        if (!skb) {
                err = -ENOBUFS;
                goto send_fail;
        }

        nlh = nlmsg_put(skb, 0, 0, SCSI_TRANSPORT_MSG,
                                skblen - sizeof(*nlh), 0);
        if (!nlh) {
                err = -ENOBUFS;
                goto send_fail_skb;
        }
        event = NLMSG_DATA(nlh);

        INIT_SCSI_NL_HDR(&event->snlh, SCSI_NL_TRANSPORT_FC,
                                FC_NL_ASYNC_EVENT, len);
        event->seconds = get_seconds();
        event->vendor_id = 0;
        event->host_no = shost->host_no;
        event->event_datalen = sizeof(u32);     /* bytes */
        event->event_num = event_number;
        event->event_code = event_code;
        event->event_data = event_data;

        err = nlmsg_multicast(scsi_nl_sock, skb, 0, SCSI_NL_GRP_FC_EVENTS,
                              GFP_KERNEL);
        if (err && (err != -ESRCH))     /* filter no recipient errors */
                /* nlmsg_multicast already kfree_skb'd */
                goto send_fail;

        return;

send_fail_skb:
        kfree_skb(skb);
send_fail:
        name = get_fc_host_event_code_name(event_code);
        printk(KERN_WARNING
                "%s: Dropped Event : host %d %s data 0x%08x - err %d\n",
                __FUNCTION__, shost->host_no,
                (name) ? name : "<unknown>", event_data, err);
        return;
}
EXPORT_SYMBOL(fc_host_post_event);


/**
 * fc_host_post_vendor_event - called to post a vendor unique event on an fc_host
 * @shost:              host the event occurred on
 * @event_number:       fc event number obtained from get_fc_event_number()
 * @data_len:           amount, in bytes, of vendor unique data
 * @data_buf:           pointer to vendor unique data
 * @vendor_id:          Vendor id
 *
 * Notes:
 *      This routine assumes no locks are held on entry.
 */
void
fc_host_post_vendor_event(struct Scsi_Host *shost, u32 event_number,
                u32 data_len, char * data_buf, u64 vendor_id)
{
        struct sk_buff *skb;
        struct nlmsghdr *nlh;
        struct fc_nl_event *event;
        u32 len, skblen;
        int err;

        if (!scsi_nl_sock) {
                err = -ENOENT;
                goto send_vendor_fail;
        }

        len = FC_NL_MSGALIGN(sizeof(*event) + data_len);
        skblen = NLMSG_SPACE(len);

        skb = alloc_skb(skblen, GFP_KERNEL);
        if (!skb) {
                err = -ENOBUFS;
                goto send_vendor_fail;
        }

        nlh = nlmsg_put(skb, 0, 0, SCSI_TRANSPORT_MSG,
                                skblen - sizeof(*nlh), 0);
        if (!nlh) {
                err = -ENOBUFS;
                goto send_vendor_fail_skb;
        }
        event = NLMSG_DATA(nlh);

        INIT_SCSI_NL_HDR(&event->snlh, SCSI_NL_TRANSPORT_FC,
                                FC_NL_ASYNC_EVENT, len);
        event->seconds = get_seconds();
        event->vendor_id = vendor_id;
        event->host_no = shost->host_no;
        event->event_datalen = data_len;        /* bytes */
        event->event_num = event_number;
        event->event_code = FCH_EVT_VENDOR_UNIQUE;
        memcpy(&event->event_data, data_buf, data_len);

        err = nlmsg_multicast(scsi_nl_sock, skb, 0, SCSI_NL_GRP_FC_EVENTS,
                              GFP_KERNEL);
        if (err && (err != -ESRCH))     /* filter no recipient errors */
                /* nlmsg_multicast already kfree_skb'd */
                goto send_vendor_fail;

        return;

send_vendor_fail_skb:
        kfree_skb(skb);
send_vendor_fail:
        printk(KERN_WARNING
                "%s: Dropped Event : host %d vendor_unique - err %d\n",
                __FUNCTION__, shost->host_no, err);
        return;
}
EXPORT_SYMBOL(fc_host_post_vendor_event);



static __init int fc_transport_init(void)
{
        int error;

        atomic_set(&fc_event_seq, 0);

        error = transport_class_register(&fc_host_class);
        if (error)
                return error;
        error = transport_class_register(&fc_vport_class);
        if (error)
                return error;
        error = transport_class_register(&fc_rport_class);
        if (error)
                return error;
        return transport_class_register(&fc_transport_class);
}

static void __exit fc_transport_exit(void)
{
        transport_class_unregister(&fc_transport_class);
        transport_class_unregister(&fc_rport_class);
        transport_class_unregister(&fc_host_class);
        transport_class_unregister(&fc_vport_class);
}

/*
 * FC Remote Port Attribute Management
 */

#define fc_rport_show_function(field, format_string, sz, cast)          \
static ssize_t                                                          \
show_fc_rport_##field (struct class_device *cdev, char *buf)            \
{                                                                       \
        struct fc_rport *rport = transport_class_to_rport(cdev);        \
        struct Scsi_Host *shost = rport_to_shost(rport);                \
        struct fc_internal *i = to_fc_internal(shost->transportt);      \
        if ((i->f->get_rport_##field) &&                                \
            !((rport->port_state == FC_PORTSTATE_BLOCKED) ||            \
              (rport->port_state == FC_PORTSTATE_DELETED) ||            \
              (rport->port_state == FC_PORTSTATE_NOTPRESENT)))          \
                i->f->get_rport_##field(rport);                         \
        return snprintf(buf, sz, format_string, cast rport->field);     \
}

#define fc_rport_store_function(field)                                  \
static ssize_t                                                          \
store_fc_rport_##field(struct class_device *cdev, const char *buf,      \
                           size_t count)                                \
{                                                                       \
        int val;                                                        \
        struct fc_rport *rport = transport_class_to_rport(cdev);        \
        struct Scsi_Host *shost = rport_to_shost(rport);                \
        struct fc_internal *i = to_fc_internal(shost->transportt);      \
        char *cp;                                                       \
        if ((rport->port_state == FC_PORTSTATE_BLOCKED) ||              \
            (rport->port_state == FC_PORTSTATE_DELETED) ||              \
            (rport->port_state == FC_PORTSTATE_NOTPRESENT))             \
                return -EBUSY;                                          \
        val = simple_strtoul(buf, &cp, 0);                              \
        if (*cp && (*cp != '\n'))                                       \
                return -EINVAL;                                         \
        i->f->set_rport_##field(rport, val);                            \
        return count;                                                   \
}

#define fc_rport_rd_attr(field, format_string, sz)                      \
        fc_rport_show_function(field, format_string, sz, )              \
static FC_CLASS_DEVICE_ATTR(rport, field, S_IRUGO,                      \
                         show_fc_rport_##field, NULL)

#define fc_rport_rd_attr_cast(field, format_string, sz, cast)           \
        fc_rport_show_function(field, format_string, sz, (cast))        \
static FC_CLASS_DEVICE_ATTR(rport, field, S_IRUGO,                      \
                          show_fc_rport_##field, NULL)

#define fc_rport_rw_attr(field, format_string, sz)                      \
        fc_rport_show_function(field, format_string, sz, )              \
        fc_rport_store_function(field)                                  \
static FC_CLASS_DEVICE_ATTR(rport, field, S_IRUGO | S_IWUSR,            \
                        show_fc_rport_##field,                          \
                        store_fc_rport_##field)


#define fc_private_rport_show_function(field, format_string, sz, cast)  \
static ssize_t                                                          \
show_fc_rport_##field (struct class_device *cdev, char *buf)            \
{                                                                       \
        struct fc_rport *rport = transport_class_to_rport(cdev);        \
        return snprintf(buf, sz, format_string, cast rport->field);     \
}

#define fc_private_rport_rd_attr(field, format_string, sz)              \
        fc_private_rport_show_function(field, format_string, sz, )      \
static FC_CLASS_DEVICE_ATTR(rport, field, S_IRUGO,                      \
                         show_fc_rport_##field, NULL)

#define fc_private_rport_rd_attr_cast(field, format_string, sz, cast)   \
        fc_private_rport_show_function(field, format_string, sz, (cast)) \
static FC_CLASS_DEVICE_ATTR(rport, field, S_IRUGO,                      \
                          show_fc_rport_##field, NULL)


#define fc_private_rport_rd_enum_attr(title, maxlen)                    \
static ssize_t                                                          \
show_fc_rport_##title (struct class_device *cdev, char *buf)            \
{                                                                       \
        struct fc_rport *rport = transport_class_to_rport(cdev);        \
        const char *name;                                               \
        name = get_fc_##title##_name(rport->title);                     \
        if (!name)                                                      \
                return -EINVAL;                                         \
        return snprintf(buf, maxlen, "%s\n", name);                     \
}                                                                       \
static FC_CLASS_DEVICE_ATTR(rport, title, S_IRUGO,                      \
                        show_fc_rport_##title, NULL)


#define SETUP_RPORT_ATTRIBUTE_RD(field)                                 \
        i->private_rport_attrs[count] = class_device_attr_rport_##field; \
        i->private_rport_attrs[count].attr.mode = S_IRUGO;              \
        i->private_rport_attrs[count].store = NULL;                     \
        i->rport_attrs[count] = &i->private_rport_attrs[count];         \
        if (i->f->show_rport_##field)                                   \
                count++

#define SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(field)                         \
        i->private_rport_attrs[count] = class_device_attr_rport_##field; \
        i->private_rport_attrs[count].attr.mode = S_IRUGO;              \
        i->private_rport_attrs[count].store = NULL;                     \
        i->rport_attrs[count] = &i->private_rport_attrs[count];         \
        count++

#define SETUP_RPORT_ATTRIBUTE_RW(field)                                 \
        i->private_rport_attrs[count] = class_device_attr_rport_##field; \
        if (!i->f->set_rport_##field) {                                 \
                i->private_rport_attrs[count].attr.mode = S_IRUGO;      \
                i->private_rport_attrs[count].store = NULL;             \
        }                                                               \
        i->rport_attrs[count] = &i->private_rport_attrs[count];         \
        if (i->f->show_rport_##field)                                   \
                count++

#define SETUP_PRIVATE_RPORT_ATTRIBUTE_RW(field)                         \
{                                                                       \
        i->private_rport_attrs[count] = class_device_attr_rport_##field; \
        i->rport_attrs[count] = &i->private_rport_attrs[count];         \
        count++;                                                        \
}


/* The FC Transport Remote Port Attributes: */

/* Fixed Remote Port Attributes */

fc_private_rport_rd_attr(maxframe_size, "%u bytes\n", 20);

static ssize_t
show_fc_rport_supported_classes (struct class_device *cdev, char *buf)
{
        struct fc_rport *rport = transport_class_to_rport(cdev);
        if (rport->supported_classes == FC_COS_UNSPECIFIED)
                return snprintf(buf, 20, "unspecified\n");
        return get_fc_cos_names(rport->supported_classes, buf);
}
static FC_CLASS_DEVICE_ATTR(rport, supported_classes, S_IRUGO,
                show_fc_rport_supported_classes, NULL);

/* Dynamic Remote Port Attributes */

/*
 * dev_loss_tmo attribute
 */
fc_rport_show_function(dev_loss_tmo, "%d\n", 20, )
static ssize_t
store_fc_rport_dev_loss_tmo(struct class_device *cdev, const char *buf,
                           size_t count)
{
        int val;
        struct fc_rport *rport = transport_class_to_rport(cdev);
        struct Scsi_Host *shost = rport_to_shost(rport);
        struct fc_internal *i = to_fc_internal(shost->transportt);
        char *cp;
        if ((rport->port_state == FC_PORTSTATE_BLOCKED) ||
            (rport->port_state == FC_PORTSTATE_DELETED) ||
            (rport->port_state == FC_PORTSTATE_NOTPRESENT))
                return -EBUSY;
        val = simple_strtoul(buf, &cp, 0);
        if ((*cp && (*cp != '\n')) ||
            (val < 0) || (val > SCSI_DEVICE_BLOCK_MAX_TIMEOUT))
                return -EINVAL;
        i->f->set_rport_dev_loss_tmo(rport, val);
        return count;
}
static FC_CLASS_DEVICE_ATTR(rport, dev_loss_tmo, S_IRUGO | S_IWUSR,
                show_fc_rport_dev_loss_tmo, store_fc_rport_dev_loss_tmo);


/* Private Remote Port Attributes */

fc_private_rport_rd_attr_cast(node_name, "0x%llx\n", 20, unsigned long long);
fc_private_rport_rd_attr_cast(port_name, "0x%llx\n", 20, unsigned long long);
fc_private_rport_rd_attr(port_id, "0x%06x\n", 20);

static ssize_t
show_fc_rport_roles (struct class_device *cdev, char *buf)
{
        struct fc_rport *rport = transport_class_to_rport(cdev);

        /* identify any roles that are port_id specific */
        if ((rport->port_id != -1) &&
            (rport->port_id & FC_WELLKNOWN_PORTID_MASK) ==
                                        FC_WELLKNOWN_PORTID_MASK) {
                switch (rport->port_id & FC_WELLKNOWN_ROLE_MASK) {
                case FC_FPORT_PORTID:
                        return snprintf(buf, 30, "Fabric Port\n");
                case FC_FABCTLR_PORTID:
                        return snprintf(buf, 30, "Fabric Controller\n");
                case FC_DIRSRVR_PORTID:
                        return snprintf(buf, 30, "Directory Server\n");
                case FC_TIMESRVR_PORTID:
                        return snprintf(buf, 30, "Time Server\n");
                case FC_MGMTSRVR_PORTID:
                        return snprintf(buf, 30, "Management Server\n");
                default:
                        return snprintf(buf, 30, "Unknown Fabric Entity\n");
                }
        } else {
                if (rport->roles == FC_PORT_ROLE_UNKNOWN)
                        return snprintf(buf, 20, "unknown\n");
                return get_fc_port_roles_names(rport->roles, buf);
        }
}
static FC_CLASS_DEVICE_ATTR(rport, roles, S_IRUGO,
                show_fc_rport_roles, NULL);

fc_private_rport_rd_enum_attr(port_state, FC_PORTSTATE_MAX_NAMELEN);
fc_private_rport_rd_attr(scsi_target_id, "%d\n", 20);

/*
 * fast_io_fail_tmo attribute
 */
static ssize_t
show_fc_rport_fast_io_fail_tmo (struct class_device *cdev, char *buf)
{
        struct fc_rport *rport = transport_class_to_rport(cdev);

        if (rport->fast_io_fail_tmo == -1)
                return snprintf(buf, 5, "off\n");
        return snprintf(buf, 20, "%d\n", rport->fast_io_fail_tmo);
}

static ssize_t
store_fc_rport_fast_io_fail_tmo(struct class_device *cdev, const char *buf,
                           size_t count)
{
        int val;
        char *cp;
        struct fc_rport *rport = transport_class_to_rport(cdev);

        if ((rport->port_state == FC_PORTSTATE_BLOCKED) ||
            (rport->port_state == FC_PORTSTATE_DELETED) ||
            (rport->port_state == FC_PORTSTATE_NOTPRESENT))
                return -EBUSY;
        if (strncmp(buf, "off", 3) == 0)
                rport->fast_io_fail_tmo = -1;
        else {
                val = simple_strtoul(buf, &cp, 0);
                if ((*cp && (*cp != '\n')) ||
                    (val < 0) || (val >= rport->dev_loss_tmo))
                        return -EINVAL;
                rport->fast_io_fail_tmo = val;
        }
        return count;
}
static FC_CLASS_DEVICE_ATTR(rport, fast_io_fail_tmo, S_IRUGO | S_IWUSR,
        show_fc_rport_fast_io_fail_tmo, store_fc_rport_fast_io_fail_tmo);


/*
 * FC SCSI Target Attribute Management
 */

/*
 * Note: in the target show function we recognize when the remote
 *  port is in the heirarchy and do not allow the driver to get
 *  involved in sysfs functions. The driver only gets involved if
 *  it's the "old" style that doesn't use rports.
 */
#define fc_starget_show_function(field, format_string, sz, cast)        \
static ssize_t                                                          \
show_fc_starget_##field (struct class_device *cdev, char *buf)          \
{                                                                       \
        struct scsi_target *starget = transport_class_to_starget(cdev); \
        struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
        struct fc_internal *i = to_fc_internal(shost->transportt);      \
        struct fc_rport *rport = starget_to_rport(starget);             \
        if (rport)                                                      \
                fc_starget_##field(starget) = rport->field;             \
        else if (i->f->get_starget_##field)                             \
                i->f->get_starget_##field(starget);                     \
        return snprintf(buf, sz, format_string,                         \
                cast fc_starget_##field(starget));                      \
}

#define fc_starget_rd_attr(field, format_string, sz)                    \
        fc_starget_show_function(field, format_string, sz, )            \
static FC_CLASS_DEVICE_ATTR(starget, field, S_IRUGO,                    \
                         show_fc_starget_##field, NULL)

#define fc_starget_rd_attr_cast(field, format_string, sz, cast)         \
        fc_starget_show_function(field, format_string, sz, (cast))      \
static FC_CLASS_DEVICE_ATTR(starget, field, S_IRUGO,                    \
                          show_fc_starget_##field, NULL)

#define SETUP_STARGET_ATTRIBUTE_RD(field)                               \
        i->private_starget_attrs[count] = class_device_attr_starget_##field; \
        i->private_starget_attrs[count].attr.mode = S_IRUGO;            \
        i->private_starget_attrs[count].store = NULL;                   \
        i->starget_attrs[count] = &i->private_starget_attrs[count];     \
        if (i->f->show_starget_##field)                                 \
                count++

#define SETUP_STARGET_ATTRIBUTE_RW(field)                               \
        i->private_starget_attrs[count] = class_device_attr_starget_##field; \
        if (!i->f->set_starget_##field) {                               \
                i->private_starget_attrs[count].attr.mode = S_IRUGO;    \
                i->private_starget_attrs[count].store = NULL;           \
        }                                                               \
        i->starget_attrs[count] = &i->private_starget_attrs[count];     \
        if (i->f->show_starget_##field)                                 \
                count++

/* The FC Transport SCSI Target Attributes: */
fc_starget_rd_attr_cast(node_name, "0x%llx\n", 20, unsigned long long);
fc_starget_rd_attr_cast(port_name, "0x%llx\n", 20, unsigned long long);
fc_starget_rd_attr(port_id, "0x%06x\n", 20);


/*
 * FC Virtual Port Attribute Management
 */

#define fc_vport_show_function(field, format_string, sz, cast)          \
static ssize_t                                                          \
show_fc_vport_##field (struct class_device *cdev, char *buf)            \
{                                                                       \
        struct fc_vport *vport = transport_class_to_vport(cdev);        \
        struct Scsi_Host *shost = vport_to_shost(vport);                \
        struct fc_internal *i = to_fc_internal(shost->transportt);      \
        if ((i->f->get_vport_##field) &&                                \
            !(vport->flags & (FC_VPORT_DEL | FC_VPORT_CREATING)))       \
                i->f->get_vport_##field(vport);                         \
        return snprintf(buf, sz, format_string, cast vport->field);     \
}

#define fc_vport_store_function(field)                                  \
static ssize_t                                                          \
store_fc_vport_##field(struct class_device *cdev, const char *buf,      \
                           size_t count)                                \
{                                                                       \
        int val;                                                        \
        struct fc_vport *vport = transport_class_to_vport(cdev);        \
        struct Scsi_Host *shost = vport_to_shost(vport);                \
        struct fc_internal *i = to_fc_internal(shost->transportt);      \
        char *cp;                                                       \
        if (vport->flags & (FC_VPORT_DEL | FC_VPORT_CREATING))  \
                return -EBUSY;                                          \
        val = simple_strtoul(buf, &cp, 0);                              \
        if (*cp && (*cp != '\n'))                                       \
                return -EINVAL;                                         \
        i->f->set_vport_##field(vport, val);                            \
        return count;                                                   \
}

#define fc_vport_store_str_function(field, slen)                        \
static ssize_t                                                          \
store_fc_vport_##field(struct class_device *cdev, const char *buf,      \
                           size_t count)                                \
{                                                                       \
        struct fc_vport *vport = transport_class_to_vport(cdev);        \
        struct Scsi_Host *shost = vport_to_shost(vport);                \
        struct fc_internal *i = to_fc_internal(shost->transportt);      \
        unsigned int cnt=count;                                         \
                                                                        \
        /* count may include a LF at end of string */                   \
        if (buf[cnt-1] == '\n')                                         \
                cnt--;                                                  \
        if (cnt > ((slen) - 1))                                         \
                return -EINVAL;                                         \
        memcpy(vport->field, buf, cnt);                                 \
        i->f->set_vport_##field(vport);                                 \
        return count;                                                   \
}

#define fc_vport_rd_attr(field, format_string, sz)                      \
        fc_vport_show_function(field, format_string, sz, )              \
static FC_CLASS_DEVICE_ATTR(vport, field, S_IRUGO,                      \
                         show_fc_vport_##field, NULL)

#define fc_vport_rd_attr_cast(field, format_string, sz, cast)           \
        fc_vport_show_function(field, format_string, sz, (cast))        \
static FC_CLASS_DEVICE_ATTR(vport, field, S_IRUGO,                      \
                          show_fc_vport_##field, NULL)

#define fc_vport_rw_attr(field, format_string, sz)                      \
        fc_vport_show_function(field, format_string, sz, )              \
        fc_vport_store_function(field)                                  \
static FC_CLASS_DEVICE_ATTR(vport, field, S_IRUGO | S_IWUSR,            \
                        show_fc_vport_##field,                          \
                        store_fc_vport_##field)

#define fc_private_vport_show_function(field, format_string, sz, cast)  \
static ssize_t                                                          \
show_fc_vport_##field (struct class_device *cdev, char *buf)            \
{                                                                       \
        struct fc_vport *vport = transport_class_to_vport(cdev);        \
        return snprintf(buf, sz, format_string, cast vport->field);     \
}

#define fc_private_vport_store_u32_function(field)                      \
static ssize_t                                                          \
store_fc_vport_##field(struct class_device *cdev, const char *buf,      \
                           size_t count)                                \
{                                                                       \
        u32 val;                                                        \
        struct fc_vport *vport = transport_class_to_vport(cdev);        \
        char *cp;                                                       \
        if (vport->flags & (FC_VPORT_DEL | FC_VPORT_CREATING))          \
                return -EBUSY;                                          \
        val = simple_strtoul(buf, &cp, 0);                              \
        if (*cp && (*cp != '\n'))                                       \
                return -EINVAL;                                         \
        vport->field = val;                                             \
        return count;                                                   \
}


#define fc_private_vport_rd_attr(field, format_string, sz)              \
        fc_private_vport_show_function(field, format_string, sz, )      \
static FC_CLASS_DEVICE_ATTR(vport, field, S_IRUGO,                      \
                         show_fc_vport_##field, NULL)

#define fc_private_vport_rd_attr_cast(field, format_string, sz, cast)   \
        fc_private_vport_show_function(field, format_string, sz, (cast)) \
static FC_CLASS_DEVICE_ATTR(vport, field, S_IRUGO,                      \
                          show_fc_vport_##field, NULL)

#define fc_private_vport_rw_u32_attr(field, format_string, sz)          \
        fc_private_vport_show_function(field, format_string, sz, )      \
        fc_private_vport_store_u32_function(field)                      \
static FC_CLASS_DEVICE_ATTR(vport, field, S_IRUGO | S_IWUSR,            \
                        show_fc_vport_##field,                          \
                        store_fc_vport_##field)


#define fc_private_vport_rd_enum_attr(title, maxlen)                    \
static ssize_t                                                          \
show_fc_vport_##title (struct class_device *cdev, char *buf)            \
{                                                                       \
        struct fc_vport *vport = transport_class_to_vport(cdev);        \
        const char *name;                                               \
        name = get_fc_##title##_name(vport->title);                     \
        if (!name)                                                      \
                return -EINVAL;                                         \
        return snprintf(buf, maxlen, "%s\n", name);                     \
}                                                                       \
static FC_CLASS_DEVICE_ATTR(vport, title, S_IRUGO,                      \
                        show_fc_vport_##title, NULL)


#define SETUP_VPORT_ATTRIBUTE_RD(field)                                 \
        i->private_vport_attrs[count] = class_device_attr_vport_##field; \
        i->private_vport_attrs[count].attr.mode = S_IRUGO;              \
        i->private_vport_attrs[count].store = NULL;                     \
        i->vport_attrs[count] = &i->private_vport_attrs[count];         \
        if (i->f->get_##field)                                          \
                count++
        /* NOTE: Above MACRO differs: checks function not show bit */

#define SETUP_PRIVATE_VPORT_ATTRIBUTE_RD(field)                         \
        i->private_vport_attrs[count] = class_device_attr_vport_##field; \
        i->private_vport_attrs[count].attr.mode = S_IRUGO;              \
        i->private_vport_attrs[count].store = NULL;                     \
        i->vport_attrs[count] = &i->private_vport_attrs[count];         \
        count++

#define SETUP_VPORT_ATTRIBUTE_WR(field)                                 \
        i->private_vport_attrs[count] = class_device_attr_vport_##field; \
        i->vport_attrs[count] = &i->private_vport_attrs[count];         \
        if (i->f->field)                                                \
                count++
        /* NOTE: Above MACRO differs: checks function */

#define SETUP_VPORT_ATTRIBUTE_RW(field)                                 \
        i->private_vport_attrs[count] = class_device_attr_vport_##field; \
        if (!i->f->set_vport_##field) {                                 \
                i->private_vport_attrs[count].attr.mode = S_IRUGO;      \
                i->private_vport_attrs[count].store = NULL;             \
        }                                                               \
        i->vport_attrs[count] = &i->private_vport_attrs[count];         \
        count++
        /* NOTE: Above MACRO differs: does not check show bit */

#define SETUP_PRIVATE_VPORT_ATTRIBUTE_RW(field)                         \
{                                                                       \
        i->private_vport_attrs[count] = class_device_attr_vport_##field; \
        i->vport_attrs[count] = &i->private_vport_attrs[count];         \
        count++;                                                        \
}


/* The FC Transport Virtual Port Attributes: */

/* Fixed Virtual Port Attributes */

/* Dynamic Virtual Port Attributes */

/* Private Virtual Port Attributes */

fc_private_vport_rd_enum_attr(vport_state, FC_VPORTSTATE_MAX_NAMELEN);
fc_private_vport_rd_enum_attr(vport_last_state, FC_VPORTSTATE_MAX_NAMELEN);
fc_private_vport_rd_attr_cast(node_name, "0x%llx\n", 20, unsigned long long);
fc_private_vport_rd_attr_cast(port_name, "0x%llx\n", 20, unsigned long long);

static ssize_t
show_fc_vport_roles (struct class_device *cdev, char *buf)
{
        struct fc_vport *vport = transport_class_to_vport(cdev);

        if (vport->roles == FC_PORT_ROLE_UNKNOWN)
                return snprintf(buf, 20, "unknown\n");
        return get_fc_port_roles_names(vport->roles, buf);
}
static FC_CLASS_DEVICE_ATTR(vport, roles, S_IRUGO, show_fc_vport_roles, NULL);

fc_private_vport_rd_enum_attr(vport_type, FC_PORTTYPE_MAX_NAMELEN);

fc_private_vport_show_function(symbolic_name, "%s\n",
                FC_VPORT_SYMBOLIC_NAMELEN + 1, )
fc_vport_store_str_function(symbolic_name, FC_VPORT_SYMBOLIC_NAMELEN)
static FC_CLASS_DEVICE_ATTR(vport, symbolic_name, S_IRUGO | S_IWUSR,
                show_fc_vport_symbolic_name, store_fc_vport_symbolic_name);

static ssize_t
store_fc_vport_delete(struct class_device *cdev, const char *buf,
                           size_t count)
{
        struct fc_vport *vport = transport_class_to_vport(cdev);
        struct Scsi_Host *shost = vport_to_shost(vport);

        fc_queue_work(shost, &vport->vport_delete_work);
        return count;
}
static FC_CLASS_DEVICE_ATTR(vport, vport_delete, S_IWUSR,
                        NULL, store_fc_vport_delete);


/*
 * Enable/Disable vport
 *  Write "1" to disable, write "0" to enable
 */
static ssize_t
store_fc_vport_disable(struct class_device *cdev, const char *buf,
                           size_t count)
{
        struct fc_vport *vport = transport_class_to_vport(cdev);
        struct Scsi_Host *shost = vport_to_shost(vport);
        struct fc_internal *i = to_fc_internal(shost->transportt);
        int stat;

        if (vport->flags & (FC_VPORT_DEL | FC_VPORT_CREATING))
                return -EBUSY;

        if (*buf == '0') {
                if (vport->vport_state != FC_VPORT_DISABLED)
                        return -EALREADY;
        } else if (*buf == '1') {
                if (vport->vport_state == FC_VPORT_DISABLED)
                        return -EALREADY;
        } else
                return -EINVAL;

        stat = i->f->vport_disable(vport, ((*buf == '0') ? false : true));
        return stat ? stat : count;
}
static FC_CLASS_DEVICE_ATTR(vport, vport_disable, S_IWUSR,
                        NULL, store_fc_vport_disable);


/*
 * Host Attribute Management
 */

#define fc_host_show_function(field, format_string, sz, cast)           \
static ssize_t                                                          \
show_fc_host_##field (struct class_device *cdev, char *buf)             \
{                                                                       \
        struct Scsi_Host *shost = transport_class_to_shost(cdev);       \
        struct fc_internal *i = to_fc_internal(shost->transportt);      \
        if (i->f->get_host_##field)                                     \
                i->f->get_host_##field(shost);                          \
        return snprintf(buf, sz, format_string, cast fc_host_##field(shost)); \
}

#define fc_host_store_function(field)                                   \
static ssize_t                                                          \
store_fc_host_##field(struct class_device *cdev, const char *buf,       \
                           size_t count)                                \
{                                                                       \
        int val;                                                        \
        struct Scsi_Host *shost = transport_class_to_shost(cdev);       \
        struct fc_internal *i = to_fc_internal(shost->transportt);      \
        char *cp;                                                       \
                                                                        \
        val = simple_strtoul(buf, &cp, 0);                              \
        if (*cp && (*cp != '\n'))                                       \
                return -EINVAL;                                         \
        i->f->set_host_##field(shost, val);                             \
        return count;                                                   \
}

#define fc_host_store_str_function(field, slen)                         \
static ssize_t                                                          \
store_fc_host_##field(struct class_device *cdev, const char *buf,       \
                           size_t count)                                \
{                                                                       \
        struct Scsi_Host *shost = transport_class_to_shost(cdev);       \
        struct fc_internal *i = to_fc_internal(shost->transportt);      \
        unsigned int cnt=count;                                         \
                                                                        \
        /* count may include a LF at end of string */                   \
        if (buf[cnt-1] == '\n')                                         \
                cnt--;                                                  \
        if (cnt > ((slen) - 1))                                         \
                return -EINVAL;                                         \
        memcpy(fc_host_##field(shost), buf, cnt);                       \
        i->f->set_host_##field(shost);                                  \
        return count;                                                   \
}

#define fc_host_rd_attr(field, format_string, sz)                       \
        fc_host_show_function(field, format_string, sz, )               \
static FC_CLASS_DEVICE_ATTR(host, field, S_IRUGO,                       \
                         show_fc_host_##field, NULL)

#define fc_host_rd_attr_cast(field, format_string, sz, cast)            \
        fc_host_show_function(field, format_string, sz, (cast))         \
static FC_CLASS_DEVICE_ATTR(host, field, S_IRUGO,                       \
                          show_fc_host_##field, NULL)

#define fc_host_rw_attr(field, format_string, sz)                       \
        fc_host_show_function(field, format_string, sz, )               \
        fc_host_store_function(field)                                   \
static FC_CLASS_DEVICE_ATTR(host, field, S_IRUGO | S_IWUSR,             \
                        show_fc_host_##field,                           \
                        store_fc_host_##field)

#define fc_host_rd_enum_attr(title, maxlen)                             \
static ssize_t                                                          \
show_fc_host_##title (struct class_device *cdev, char *buf)             \
{                                                                       \
        struct Scsi_Host *shost = transport_class_to_shost(cdev);       \
        struct fc_internal *i = to_fc_internal(shost->transportt);      \
        const char *name;                                               \
        if (i->f->get_host_##title)                                     \
                i->f->get_host_##title(shost);                          \
        name = get_fc_##title##_name(fc_host_##title(shost));           \
        if (!name)                                                      \
                return -EINVAL;                                         \
        return snprintf(buf, maxlen, "%s\n", name);                     \
}                                                                       \
static FC_CLASS_DEVICE_ATTR(host, title, S_IRUGO, show_fc_host_##title, NULL)

#define SETUP_HOST_ATTRIBUTE_RD(field)                                  \
        i->private_host_attrs[count] = class_device_attr_host_##field;  \
        i->private_host_attrs[count].attr.mode = S_IRUGO;               \
        i->private_host_attrs[count].store = NULL;                      \
        i->host_attrs[count] = &i->private_host_attrs[count];           \
        if (i->f->show_host_##field)                                    \
                count++

#define SETUP_HOST_ATTRIBUTE_RD_NS(field)                               \
        i->private_host_attrs[count] = class_device_attr_host_##field;  \
        i->private_host_attrs[count].attr.mode = S_IRUGO;               \
        i->private_host_attrs[count].store = NULL;                      \
        i->host_attrs[count] = &i->private_host_attrs[count];           \
        count++

#define SETUP_HOST_ATTRIBUTE_RW(field)                                  \
        i->private_host_attrs[count] = class_device_attr_host_##field;  \
        if (!i->f->set_host_##field) {                                  \
                i->private_host_attrs[count].attr.mode = S_IRUGO;       \
                i->private_host_attrs[count].store = NULL;              \
        }                                                               \
        i->host_attrs[count] = &i->private_host_attrs[count];           \
        if (i->f->show_host_##field)                                    \
                count++


#define fc_private_host_show_function(field, format_string, sz, cast)   \
static ssize_t                                                          \
show_fc_host_##field (struct class_device *cdev, char *buf)             \
{                                                                       \
        struct Scsi_Host *shost = transport_class_to_shost(cdev);       \
        return snprintf(buf, sz, format_string, cast fc_host_##field(shost)); \
}

#define fc_private_host_rd_attr(field, format_string, sz)               \
        fc_private_host_show_function(field, format_string, sz, )       \
static FC_CLASS_DEVICE_ATTR(host, field, S_IRUGO,                       \
                         show_fc_host_##field, NULL)

#define fc_private_host_rd_attr_cast(field, format_string, sz, cast)    \
        fc_private_host_show_function(field, format_string, sz, (cast)) \
static FC_CLASS_DEVICE_ATTR(host, field, S_IRUGO,                       \
                          show_fc_host_##field, NULL)

#define SETUP_PRIVATE_HOST_ATTRIBUTE_RD(field)                  \
        i->private_host_attrs[count] = class_device_attr_host_##field;  \
        i->private_host_attrs[count].attr.mode = S_IRUGO;               \
        i->private_host_attrs[count].store = NULL;                      \
        i->host_attrs[count] = &i->private_host_attrs[count];           \
        count++

#define SETUP_PRIVATE_HOST_ATTRIBUTE_RW(field)                  \
{                                                                       \
        i->private_host_attrs[count] = class_device_attr_host_##field;  \
        i->host_attrs[count] = &i->private_host_attrs[count];           \
        count++;                                                        \
}


/* Fixed Host Attributes */

static ssize_t
show_fc_host_supported_classes (struct class_device *cdev, char *buf)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);

        if (fc_host_supported_classes(shost) == FC_COS_UNSPECIFIED)
                return snprintf(buf, 20, "unspecified\n");

        return get_fc_cos_names(fc_host_supported_classes(shost), buf);
}
static FC_CLASS_DEVICE_ATTR(host, supported_classes, S_IRUGO,
                show_fc_host_supported_classes, NULL);

static ssize_t
show_fc_host_supported_fc4s (struct class_device *cdev, char *buf)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);
        return (ssize_t)show_fc_fc4s(buf, fc_host_supported_fc4s(shost));
}
static FC_CLASS_DEVICE_ATTR(host, supported_fc4s, S_IRUGO,
                show_fc_host_supported_fc4s, NULL);

static ssize_t
show_fc_host_supported_speeds (struct class_device *cdev, char *buf)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);

        if (fc_host_supported_speeds(shost) == FC_PORTSPEED_UNKNOWN)
                return snprintf(buf, 20, "unknown\n");

        return get_fc_port_speed_names(fc_host_supported_speeds(shost), buf);
}
static FC_CLASS_DEVICE_ATTR(host, supported_speeds, S_IRUGO,
                show_fc_host_supported_speeds, NULL);


fc_private_host_rd_attr_cast(node_name, "0x%llx\n", 20, unsigned long long);
fc_private_host_rd_attr_cast(port_name, "0x%llx\n", 20, unsigned long long);
fc_private_host_rd_attr_cast(permanent_port_name, "0x%llx\n", 20,
                             unsigned long long);
fc_private_host_rd_attr(maxframe_size, "%u bytes\n", 20);
fc_private_host_rd_attr(max_npiv_vports, "%u\n", 20);
fc_private_host_rd_attr(serial_number, "%s\n", (FC_SERIAL_NUMBER_SIZE +1));


/* Dynamic Host Attributes */

static ssize_t
show_fc_host_active_fc4s (struct class_device *cdev, char *buf)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);
        struct fc_internal *i = to_fc_internal(shost->transportt);

        if (i->f->get_host_active_fc4s)
                i->f->get_host_active_fc4s(shost);

        return (ssize_t)show_fc_fc4s(buf, fc_host_active_fc4s(shost));
}
static FC_CLASS_DEVICE_ATTR(host, active_fc4s, S_IRUGO,
                show_fc_host_active_fc4s, NULL);

static ssize_t
show_fc_host_speed (struct class_device *cdev, char *buf)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);
        struct fc_internal *i = to_fc_internal(shost->transportt);

        if (i->f->get_host_speed)
                i->f->get_host_speed(shost);

        if (fc_host_speed(shost) == FC_PORTSPEED_UNKNOWN)
                return snprintf(buf, 20, "unknown\n");

        return get_fc_port_speed_names(fc_host_speed(shost), buf);
}
static FC_CLASS_DEVICE_ATTR(host, speed, S_IRUGO,
                show_fc_host_speed, NULL);


fc_host_rd_attr(port_id, "0x%06x\n", 20);
fc_host_rd_enum_attr(port_type, FC_PORTTYPE_MAX_NAMELEN);
fc_host_rd_enum_attr(port_state, FC_PORTSTATE_MAX_NAMELEN);
fc_host_rd_attr_cast(fabric_name, "0x%llx\n", 20, unsigned long long);
fc_host_rd_attr(symbolic_name, "%s\n", FC_SYMBOLIC_NAME_SIZE + 1);

fc_private_host_show_function(system_hostname, "%s\n",
                FC_SYMBOLIC_NAME_SIZE + 1, )
fc_host_store_str_function(system_hostname, FC_SYMBOLIC_NAME_SIZE)
static FC_CLASS_DEVICE_ATTR(host, system_hostname, S_IRUGO | S_IWUSR,
                show_fc_host_system_hostname, store_fc_host_system_hostname);


/* Private Host Attributes */

static ssize_t
show_fc_private_host_tgtid_bind_type(struct class_device *cdev, char *buf)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);
        const char *name;

        name = get_fc_tgtid_bind_type_name(fc_host_tgtid_bind_type(shost));
        if (!name)
                return -EINVAL;
        return snprintf(buf, FC_BINDTYPE_MAX_NAMELEN, "%s\n", name);
}

#define get_list_head_entry(pos, head, member)          \
        pos = list_entry((head)->next, typeof(*pos), member)

static ssize_t
store_fc_private_host_tgtid_bind_type(struct class_device *cdev,
        const char *buf, size_t count)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);
        struct fc_rport *rport;
        enum fc_tgtid_binding_type val;
        unsigned long flags;

        if (get_fc_tgtid_bind_type_match(buf, &val))
                return -EINVAL;

        /* if changing bind type, purge all unused consistent bindings */
        if (val != fc_host_tgtid_bind_type(shost)) {
                spin_lock_irqsave(shost->host_lock, flags);
                while (!list_empty(&fc_host_rport_bindings(shost))) {
                        get_list_head_entry(rport,
                                &fc_host_rport_bindings(shost), peers);
                        list_del(&rport->peers);
                        rport->port_state = FC_PORTSTATE_DELETED;
                        fc_queue_work(shost, &rport->rport_delete_work);
                }
                spin_unlock_irqrestore(shost->host_lock, flags);
        }

        fc_host_tgtid_bind_type(shost) = val;
        return count;
}

static FC_CLASS_DEVICE_ATTR(host, tgtid_bind_type, S_IRUGO | S_IWUSR,
                        show_fc_private_host_tgtid_bind_type,
                        store_fc_private_host_tgtid_bind_type);

static ssize_t
store_fc_private_host_issue_lip(struct class_device *cdev,
        const char *buf, size_t count)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);
        struct fc_internal *i = to_fc_internal(shost->transportt);
        int ret;

        /* ignore any data value written to the attribute */
        if (i->f->issue_fc_host_lip) {
                ret = i->f->issue_fc_host_lip(shost);
                return ret ? ret: count;
        }

        return -ENOENT;
}

static FC_CLASS_DEVICE_ATTR(host, issue_lip, S_IWUSR, NULL,
                        store_fc_private_host_issue_lip);

fc_private_host_rd_attr(npiv_vports_inuse, "%u\n", 20);


/*
 * Host Statistics Management
 */

/* Show a given an attribute in the statistics group */
static ssize_t
fc_stat_show(const struct class_device *cdev, char *buf, unsigned long offset)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);
        struct fc_internal *i = to_fc_internal(shost->transportt);
        struct fc_host_statistics *stats;
        ssize_t ret = -ENOENT;

        if (offset > sizeof(struct fc_host_statistics) ||
            offset % sizeof(u64) != 0)
                WARN_ON(1);

        if (i->f->get_fc_host_stats) {
                stats = (i->f->get_fc_host_stats)(shost);
                if (stats)
                        ret = snprintf(buf, 20, "0x%llx\n",
                              (unsigned long long)*(u64 *)(((u8 *) stats) + offset));
        }
        return ret;
}


/* generate a read-only statistics attribute */
#define fc_host_statistic(name)                                         \
static ssize_t show_fcstat_##name(struct class_device *cd, char *buf)   \
{                                                                       \
        return fc_stat_show(cd, buf,                                    \
                            offsetof(struct fc_host_statistics, name)); \
}                                                                       \
static FC_CLASS_DEVICE_ATTR(host, name, S_IRUGO, show_fcstat_##name, NULL)

fc_host_statistic(seconds_since_last_reset);
fc_host_statistic(tx_frames);
fc_host_statistic(tx_words);
fc_host_statistic(rx_frames);
fc_host_statistic(rx_words);
fc_host_statistic(lip_count);
fc_host_statistic(nos_count);
fc_host_statistic(error_frames);
fc_host_statistic(dumped_frames);
fc_host_statistic(link_failure_count);
fc_host_statistic(loss_of_sync_count);
fc_host_statistic(loss_of_signal_count);
fc_host_statistic(prim_seq_protocol_err_count);
fc_host_statistic(invalid_tx_word_count);
fc_host_statistic(invalid_crc_count);
fc_host_statistic(fcp_input_requests);
fc_host_statistic(fcp_output_requests);
fc_host_statistic(fcp_control_requests);
fc_host_statistic(fcp_input_megabytes);
fc_host_statistic(fcp_output_megabytes);

static ssize_t
fc_reset_statistics(struct class_device *cdev, const char *buf,
                           size_t count)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);
        struct fc_internal *i = to_fc_internal(shost->transportt);

        /* ignore any data value written to the attribute */
        if (i->f->reset_fc_host_stats) {
                i->f->reset_fc_host_stats(shost);
                return count;
        }

        return -ENOENT;
}
static FC_CLASS_DEVICE_ATTR(host, reset_statistics, S_IWUSR, NULL,
                                fc_reset_statistics);

static struct attribute *fc_statistics_attrs[] = {
        &class_device_attr_host_seconds_since_last_reset.attr,
        &class_device_attr_host_tx_frames.attr,
        &class_device_attr_host_tx_words.attr,
        &class_device_attr_host_rx_frames.attr,
        &class_device_attr_host_rx_words.attr,
        &class_device_attr_host_lip_count.attr,
        &class_device_attr_host_nos_count.attr,
        &class_device_attr_host_error_frames.attr,
        &class_device_attr_host_dumped_frames.attr,
        &class_device_attr_host_link_failure_count.attr,
        &class_device_attr_host_loss_of_sync_count.attr,
        &class_device_attr_host_loss_of_signal_count.attr,
        &class_device_attr_host_prim_seq_protocol_err_count.attr,
        &class_device_attr_host_invalid_tx_word_count.attr,
        &class_device_attr_host_invalid_crc_count.attr,
        &class_device_attr_host_fcp_input_requests.attr,
        &class_device_attr_host_fcp_output_requests.attr,
        &class_device_attr_host_fcp_control_requests.attr,
        &class_device_attr_host_fcp_input_megabytes.attr,
        &class_device_attr_host_fcp_output_megabytes.attr,
        &class_device_attr_host_reset_statistics.attr,
        NULL
};

static struct attribute_group fc_statistics_group = {
        .name = "statistics",
        .attrs = fc_statistics_attrs,
};


/* Host Vport Attributes */

static int
fc_parse_wwn(const char *ns, u64 *nm)
{
        unsigned int i, j;
        u8 wwn[8];

        memset(wwn, 0, sizeof(wwn));

        /* Validate and store the new name */
        for (i=0, j=0; i < 16; i++) {
                if ((*ns >= 'a') && (*ns <= 'f'))
                        j = ((j << 4) | ((*ns++ -'a') + 10));
                else if ((*ns >= 'A') && (*ns <= 'F'))
                        j = ((j << 4) | ((*ns++ -'A') + 10));
                else if ((*ns >= '0') && (*ns <= '9'))
                        j = ((j << 4) | (*ns++ -'0'));
                else
                        return -EINVAL;
                if (i % 2) {
                        wwn[i/2] = j & 0xff;
                        j = 0;
                }
        }

        *nm = wwn_to_u64(wwn);

        return 0;
}


/*
 * "Short-cut" sysfs variable to create a new vport on a FC Host.
 * Input is a string of the form "<WWPN>:<WWNN>". Other attributes
 * will default to a NPIV-based FCP_Initiator; The WWNs are specified
 * as hex characters, and may *not* contain any prefixes (e.g. 0x, x, etc)
 */
static ssize_t
store_fc_host_vport_create(struct class_device *cdev, const char *buf,
                           size_t count)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);
        struct fc_vport_identifiers vid;
        struct fc_vport *vport;
        unsigned int cnt=count;
        int stat;

        memset(&vid, 0, sizeof(vid));

        /* count may include a LF at end of string */
        if (buf[cnt-1] == '\n')
                cnt--;

        /* validate we have enough characters for WWPN */
        if ((cnt != (16+1+16)) || (buf[16] != ':'))
                return -EINVAL;

        stat = fc_parse_wwn(&buf[0], &vid.port_name);
        if (stat)
                return stat;

        stat = fc_parse_wwn(&buf[17], &vid.node_name);
        if (stat)
                return stat;

        vid.roles = FC_PORT_ROLE_FCP_INITIATOR;
        vid.vport_type = FC_PORTTYPE_NPIV;
        /* vid.symbolic_name is already zero/NULL's */
        vid.disable = false;            /* always enabled */

        /* we only allow support on Channel 0 !!! */
        stat = fc_vport_create(shost, 0, &shost->shost_gendev, &vid, &vport);
        return stat ? stat : count;
}
static FC_CLASS_DEVICE_ATTR(host, vport_create, S_IWUSR, NULL,
                        store_fc_host_vport_create);


/*
 * "Short-cut" sysfs variable to delete a vport on a FC Host.
 * Vport is identified by a string containing "<WWPN>:<WWNN>".
 * The WWNs are specified as hex characters, and may *not* contain
 * any prefixes (e.g. 0x, x, etc)
 */
static ssize_t
store_fc_host_vport_delete(struct class_device *cdev, const char *buf,
                           size_t count)
{
        struct Scsi_Host *shost = transport_class_to_shost(cdev);
        struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
        struct fc_vport *vport;
        u64 wwpn, wwnn;
        unsigned long flags;
        unsigned int cnt=count;
        int stat, match;

        /* count may include a LF at end of string */
        if (buf[cnt-1] == '\n')
                cnt--;

        /* validate we have enough characters for WWPN */
        if ((cnt != (16+1+16)) || (buf[16] != ':'))
                return -EINVAL;

        stat = fc_parse_wwn(&buf[0], &wwpn);
        if (stat)
                return stat;

        stat = fc_parse_wwn(&buf[17], &wwnn);
        if (stat)
                return stat;

        spin_lock_irqsave(shost->host_lock, flags);
        match = 0;
        /* we only allow support on Channel 0 !!! */
        list_for_each_entry(vport, &fc_host->vports, peers) {
                if ((vport->channel == 0) &&
                    (vport->port_name == wwpn) && (vport->node_name == wwnn)) {
                        match = 1;
                        break;
                }
        }
        spin_unlock_irqrestore(shost->host_lock, flags);

        if (!match)
                return -ENODEV;

        stat = fc_vport_terminate(vport);
        return stat ? stat : count;
}
static FC_CLASS_DEVICE_ATTR(host, vport_delete, S_IWUSR, NULL,
                        store_fc_host_vport_delete);


static int fc_host_match(struct attribute_container *cont,
                          struct device *dev)
{
        struct Scsi_Host *shost;
        struct fc_internal *i;

        if (!scsi_is_host_device(dev))
                return 0;

        shost = dev_to_shost(dev);
        if (!shost->transportt  || shost->transportt->host_attrs.ac.class
            != &fc_host_class.class)
                return 0;

        i = to_fc_internal(shost->transportt);

        return &i->t.host_attrs.ac == cont;
}

static int fc_target_match(struct attribute_container *cont,
                            struct device *dev)
{
        struct Scsi_Host *shost;
        struct fc_internal *i;

        if (!scsi_is_target_device(dev))
                return 0;

        shost = dev_to_shost(dev->parent);
        if (!shost->transportt  || shost->transportt->host_attrs.ac.class
            != &fc_host_class.class)
                return 0;

        i = to_fc_internal(shost->transportt);

        return &i->t.target_attrs.ac == cont;
}

static void fc_rport_dev_release(struct device *dev)
{
        struct fc_rport *rport = dev_to_rport(dev);
        put_device(dev->parent);
        kfree(rport);
}

int scsi_is_fc_rport(const struct device *dev)
{
        return dev->release == fc_rport_dev_release;
}
EXPORT_SYMBOL(scsi_is_fc_rport);

static int fc_rport_match(struct attribute_container *cont,
                            struct device *dev)
{
        struct Scsi_Host *shost;
        struct fc_internal *i;

        if (!scsi_is_fc_rport(dev))
                return 0;

        shost = dev_to_shost(dev->parent);
        if (!shost->transportt  || shost->transportt->host_attrs.ac.class
            != &fc_host_class.class)
                return 0;

        i = to_fc_internal(shost->transportt);

        return &i->rport_attr_cont.ac == cont;
}


static void fc_vport_dev_release(struct device *dev)
{
        struct fc_vport *vport = dev_to_vport(dev);
        put_device(dev->parent);                /* release kobj parent */
        kfree(vport);
}

int scsi_is_fc_vport(const struct device *dev)
{
        return dev->release == fc_vport_dev_release;
}
EXPORT_SYMBOL(scsi_is_fc_vport);

static int fc_vport_match(struct attribute_container *cont,
                            struct device *dev)
{
        struct fc_vport *vport;
        struct Scsi_Host *shost;
        struct fc_internal *i;

        if (!scsi_is_fc_vport(dev))
                return 0;
        vport = dev_to_vport(dev);

        shost = vport_to_shost(vport);
        if (!shost->transportt  || shost->transportt->host_attrs.ac.class
            != &fc_host_class.class)
                return 0;

        i = to_fc_internal(shost->transportt);
        return &i->vport_attr_cont.ac == cont;
}


/**
 * fc_timed_out - FC Transport I/O timeout intercept handler
 * @scmd:       The SCSI command which timed out
 *
 * This routine protects against error handlers getting invoked while a
 * rport is in a blocked state, typically due to a temporarily loss of
 * connectivity. If the error handlers are allowed to proceed, requests
 * to abort i/o, reset the target, etc will likely fail as there is no way
 * to communicate with the device to perform the requested function. These
 * failures may result in the midlayer taking the device offline, requiring
 * manual intervention to restore operation.
 *
 * This routine, called whenever an i/o times out, validates the state of
 * the underlying rport. If the rport is blocked, it returns
 * EH_RESET_TIMER, which will continue to reschedule the timeout.
 * Eventually, either the device will return, or devloss_tmo will fire,
 * and when the timeout then fires, it will be handled normally.
 * If the rport is not blocked, normal error handling continues.
 *
 * Notes:
 *      This routine assumes no locks are held on entry.
 */
static enum scsi_eh_timer_return
fc_timed_out(struct scsi_cmnd *scmd)
{
        struct fc_rport *rport = starget_to_rport(scsi_target(scmd->device));

        if (rport->port_state == FC_PORTSTATE_BLOCKED)
                return EH_RESET_TIMER;

        return EH_NOT_HANDLED;
}

/*
 * Must be called with shost->host_lock held
 */
static int fc_user_scan(struct Scsi_Host *shost, uint channel,
                uint id, uint lun)
{
        struct fc_rport *rport;

        list_for_each_entry(rport, &fc_host_rports(shost), peers) {
                if (rport->scsi_target_id == -1)
                        continue;

                if (rport->port_state != FC_PORTSTATE_ONLINE)
                        continue;

                if ((channel == SCAN_WILD_CARD || channel == rport->channel) &&
                    (id == SCAN_WILD_CARD || id == rport->scsi_target_id)) {
                        scsi_scan_target(&rport->dev, rport->channel,
                                         rport->scsi_target_id, lun, 1);
                }
        }

        return 0;
}

static int fc_tsk_mgmt_response(struct Scsi_Host *shost, u64 nexus, u64 tm_id,
                                int result)
{
        struct fc_internal *i = to_fc_internal(shost->transportt);
        return i->f->tsk_mgmt_response(shost, nexus, tm_id, result);
}

static int fc_it_nexus_response(struct Scsi_Host *shost, u64 nexus, int result)
{
        struct fc_internal *i = to_fc_internal(shost->transportt);
        return i->f->it_nexus_response(shost, nexus, result);
}

struct scsi_transport_template *
fc_attach_transport(struct fc_function_template *ft)
{
        int count;
        struct fc_internal *i = kzalloc(sizeof(struct fc_internal),
                                        GFP_KERNEL);

        if (unlikely(!i))
                return NULL;

        i->t.target_attrs.ac.attrs = &i->starget_attrs[0];
        i->t.target_attrs.ac.class = &fc_transport_class.class;
        i->t.target_attrs.ac.match = fc_target_match;
        i->t.target_size = sizeof(struct fc_starget_attrs);
        transport_container_register(&i->t.target_attrs);

        i->t.host_attrs.ac.attrs = &i->host_attrs[0];
        i->t.host_attrs.ac.class = &fc_host_class.class;
        i->t.host_attrs.ac.match = fc_host_match;
        i->t.host_size = sizeof(struct fc_host_attrs);
        if (ft->get_fc_host_stats)
                i->t.host_attrs.statistics = &fc_statistics_group;
        transport_container_register(&i->t.host_attrs);

        i->rport_attr_cont.ac.attrs = &i->rport_attrs[0];
        i->rport_attr_cont.ac.class = &fc_rport_class.class;
        i->rport_attr_cont.ac.match = fc_rport_match;
        transport_container_register(&i->rport_attr_cont);

        i->vport_attr_cont.ac.attrs = &i->vport_attrs[0];
        i->vport_attr_cont.ac.class = &fc_vport_class.class;
        i->vport_attr_cont.ac.match = fc_vport_match;
        transport_container_register(&i->vport_attr_cont);

        i->f = ft;

        /* Transport uses the shost workq for scsi scanning */
        i->t.create_work_queue = 1;

        i->t.eh_timed_out = fc_timed_out;

        i->t.user_scan = fc_user_scan;

        /* target-mode drivers' functions */
        i->t.tsk_mgmt_response = fc_tsk_mgmt_response;
        i->t.it_nexus_response = fc_it_nexus_response;

        /*
         * Setup SCSI Target Attributes.
         */
        count = 0;
        SETUP_STARGET_ATTRIBUTE_RD(node_name);
        SETUP_STARGET_ATTRIBUTE_RD(port_name);
        SETUP_STARGET_ATTRIBUTE_RD(port_id);

        BUG_ON(count > FC_STARGET_NUM_ATTRS);

        i->starget_attrs[count] = NULL;


        /*
         * Setup SCSI Host Attributes.
         */
        count=0;
        SETUP_HOST_ATTRIBUTE_RD(node_name);
        SETUP_HOST_ATTRIBUTE_RD(port_name);
        SETUP_HOST_ATTRIBUTE_RD(permanent_port_name);
        SETUP_HOST_ATTRIBUTE_RD(supported_classes);
        SETUP_HOST_ATTRIBUTE_RD(supported_fc4s);
        SETUP_HOST_ATTRIBUTE_RD(supported_speeds);
        SETUP_HOST_ATTRIBUTE_RD(maxframe_size);
        if (ft->vport_create) {
                SETUP_HOST_ATTRIBUTE_RD_NS(max_npiv_vports);
                SETUP_HOST_ATTRIBUTE_RD_NS(npiv_vports_inuse);
        }
        SETUP_HOST_ATTRIBUTE_RD(serial_number);

        SETUP_HOST_ATTRIBUTE_RD(port_id);
        SETUP_HOST_ATTRIBUTE_RD(port_type);
        SETUP_HOST_ATTRIBUTE_RD(port_state);
        SETUP_HOST_ATTRIBUTE_RD(active_fc4s);
        SETUP_HOST_ATTRIBUTE_RD(speed);
        SETUP_HOST_ATTRIBUTE_RD(fabric_name);
        SETUP_HOST_ATTRIBUTE_RD(symbolic_name);
        SETUP_HOST_ATTRIBUTE_RW(system_hostname);

        /* Transport-managed attributes */
        SETUP_PRIVATE_HOST_ATTRIBUTE_RW(tgtid_bind_type);
        if (ft->issue_fc_host_lip)
                SETUP_PRIVATE_HOST_ATTRIBUTE_RW(issue_lip);
        if (ft->vport_create)
                SETUP_PRIVATE_HOST_ATTRIBUTE_RW(vport_create);
        if (ft->vport_delete)
                SETUP_PRIVATE_HOST_ATTRIBUTE_RW(vport_delete);

        BUG_ON(count > FC_HOST_NUM_ATTRS);

        i->host_attrs[count] = NULL;

        /*
         * Setup Remote Port Attributes.
         */
        count=0;
        SETUP_RPORT_ATTRIBUTE_RD(maxframe_size);
        SETUP_RPORT_ATTRIBUTE_RD(supported_classes);
        SETUP_RPORT_ATTRIBUTE_RW(dev_loss_tmo);
        SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(node_name);
        SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(port_name);
        SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(port_id);
        SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(roles);
        SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(port_state);
        SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(scsi_target_id);
        if (ft->terminate_rport_io)
                SETUP_PRIVATE_RPORT_ATTRIBUTE_RW(fast_io_fail_tmo);

        BUG_ON(count > FC_RPORT_NUM_ATTRS);

        i->rport_attrs[count] = NULL;

        /*
         * Setup Virtual Port Attributes.
         */
        count=0;
        SETUP_PRIVATE_VPORT_ATTRIBUTE_RD(vport_state);
        SETUP_PRIVATE_VPORT_ATTRIBUTE_RD(vport_last_state);
        SETUP_PRIVATE_VPORT_ATTRIBUTE_RD(node_name);
        SETUP_PRIVATE_VPORT_ATTRIBUTE_RD(port_name);
        SETUP_PRIVATE_VPORT_ATTRIBUTE_RD(roles);
        SETUP_PRIVATE_VPORT_ATTRIBUTE_RD(vport_type);
        SETUP_VPORT_ATTRIBUTE_RW(symbolic_name);
        SETUP_VPORT_ATTRIBUTE_WR(vport_delete);
        SETUP_VPORT_ATTRIBUTE_WR(vport_disable);

        BUG_ON(count > FC_VPORT_NUM_ATTRS);

        i->vport_attrs[count] = NULL;

        return &i->t;
}
EXPORT_SYMBOL(fc_attach_transport);

void fc_release_transport(struct scsi_transport_template *t)
{
        struct fc_internal *i = to_fc_internal(t);

        transport_container_unregister(&i->t.target_attrs);
        transport_container_unregister(&i->t.host_attrs);
        transport_container_unregister(&i->rport_attr_cont);
        transport_container_unregister(&i->vport_attr_cont);

        kfree(i);
}
EXPORT_SYMBOL(fc_release_transport);

/**
 * fc_queue_work - Queue work to the fc_host workqueue.
 * @shost:      Pointer to Scsi_Host bound to fc_host.
 * @work:       Work to queue for execution.
 *
 * Return value:
 *      1 - work queued for execution
 *      0 - work is already queued
 *      -EINVAL - work queue doesn't exist
 */
static int
fc_queue_work(struct Scsi_Host *shost, struct work_struct *work)
{
        if (unlikely(!fc_host_work_q(shost))) {
                printk(KERN_ERR
                        "ERROR: FC host '%s' attempted to queue work, "
                        "when no workqueue created.\n", shost->hostt->name);
                dump_stack();

                return -EINVAL;
        }

        return queue_work(fc_host_work_q(shost), work);
}

/**
 * fc_flush_work - Flush a fc_host's workqueue.
 * @shost:      Pointer to Scsi_Host bound to fc_host.
 */
static void
fc_flush_work(struct Scsi_Host *shost)
{
        if (!fc_host_work_q(shost)) {
                printk(KERN_ERR
                        "ERROR: FC host '%s' attempted to flush work, "
                        "when no workqueue created.\n", shost->hostt->name);
                dump_stack();
                return;
        }

        flush_workqueue(fc_host_work_q(shost));
}

/**
 * fc_queue_devloss_work - Schedule work for the fc_host devloss workqueue.
 * @shost:      Pointer to Scsi_Host bound to fc_host.
 * @work:       Work to queue for execution.
 * @delay:      jiffies to delay the work queuing
 *
 * Return value:
 *      1 on success / 0 already queued / < 0 for error
 */
static int
fc_queue_devloss_work(struct Scsi_Host *shost, struct delayed_work *work,
                                unsigned long delay)
{
        if (unlikely(!fc_host_devloss_work_q(shost))) {
                printk(KERN_ERR
                        "ERROR: FC host '%s' attempted to queue work, "
                        "when no workqueue created.\n", shost->hostt->name);
                dump_stack();

                return -EINVAL;
        }

        return queue_delayed_work(fc_host_devloss_work_q(shost), work, delay);
}

/**
 * fc_flush_devloss - Flush a fc_host's devloss workqueue.
 * @shost:      Pointer to Scsi_Host bound to fc_host.
 */
static void
fc_flush_devloss(struct Scsi_Host *shost)
{
        if (!fc_host_devloss_work_q(shost)) {
                printk(KERN_ERR
                        "ERROR: FC host '%s' attempted to flush work, "
                        "when no workqueue created.\n", shost->hostt->name);
                dump_stack();
                return;
        }

        flush_workqueue(fc_host_devloss_work_q(shost));
}


/**
 * fc_remove_host - called to terminate any fc_transport-related elements for a scsi host.
 * @shost:      Which &Scsi_Host
 *
 * This routine is expected to be called immediately preceeding the
 * a driver's call to scsi_remove_host().
 *
 * WARNING: A driver utilizing the fc_transport, which fails to call
 *   this routine prior to scsi_remove_host(), will leave dangling
 *   objects in /sys/class/fc_remote_ports. Access to any of these
 *   objects can result in a system crash !!!
 *
 * Notes:
 *      This routine assumes no locks are held on entry.
 */
void
fc_remove_host(struct Scsi_Host *shost)
{
        struct fc_vport *vport = NULL, *next_vport = NULL;
        struct fc_rport *rport = NULL, *next_rport = NULL;
        struct workqueue_struct *work_q;
        struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
        unsigned long flags;

        spin_lock_irqsave(shost->host_lock, flags);

        /* Remove any vports */
        list_for_each_entry_safe(vport, next_vport, &fc_host->vports, peers)
                fc_queue_work(shost, &vport->vport_delete_work);

        /* Remove any remote ports */
        list_for_each_entry_safe(rport, next_rport,
                        &fc_host->rports, peers) {
                list_del(&rport->peers);
                rport->port_state = FC_PORTSTATE_DELETED;
                fc_queue_work(shost, &rport->rport_delete_work);
        }

        list_for_each_entry_safe(rport, next_rport,
                        &fc_host->rport_bindings, peers) {
                list_del(&rport->peers);
                rport->port_state = FC_PORTSTATE_DELETED;
                fc_queue_work(shost, &rport->rport_delete_work);
        }

        spin_unlock_irqrestore(shost->host_lock, flags);

        /* flush all scan work items */
        scsi_flush_work(shost);

        /* flush all stgt delete, and rport delete work items, then kill it  */
        if (fc_host->work_q) {
                work_q = fc_host->work_q;
                fc_host->work_q = NULL;
                destroy_workqueue(work_q);
        }

        /* flush all devloss work items, then kill it  */
        if (fc_host->devloss_work_q) {
                work_q = fc_host->devloss_work_q;
                fc_host->devloss_work_q = NULL;
                destroy_workqueue(work_q);
        }
}
EXPORT_SYMBOL(fc_remove_host);


/**
 * fc_starget_delete - called to delete the scsi decendents of an rport
 * @work:       remote port to be operated on.
 *
 * Deletes target and all sdevs.
 */
static void
fc_starget_delete(struct work_struct *work)
{
        struct fc_rport *rport =
                container_of(work, struct fc_rport, stgt_delete_work);
        struct Scsi_Host *shost = rport_to_shost(rport);
        struct fc_internal *i = to_fc_internal(shost->transportt);

        /* Involve the LLDD if possible to terminate all io on the rport. */
        if (i->f->terminate_rport_io)
                i->f->terminate_rport_io(rport);

        scsi_remove_target(&rport->dev);
}


/**
 * fc_rport_final_delete - finish rport termination and delete it.
 * @work:       remote port to be deleted.
 */
static void
fc_rport_final_delete(struct work_struct *work)
{
        struct fc_rport *rport =
                container_of(work, struct fc_rport, rport_delete_work);
        struct device *dev = &rport->dev;
        struct Scsi_Host *shost = rport_to_shost(rport);
        struct fc_internal *i = to_fc_internal(shost->transportt);
        unsigned long flags;

        /*
         * if a scan is pending, flush the SCSI Host work_q so that
         * that we can reclaim the rport scan work element.
         */
        if (rport->flags & FC_RPORT_SCAN_PENDING)
                scsi_flush_work(shost);

        /* involve the LLDD to terminate all pending i/o */
        if (i->f->terminate_rport_io)
                i->f->terminate_rport_io(rport);

        /*
         * Cancel any outstanding timers. These should really exist
         * only when rmmod'ing the LLDD and we're asking for
         * immediate termination of the rports
         */
        spin_lock_irqsave(shost->host_lock, flags);
        if (rport->flags & FC_RPORT_DEVLOSS_PENDING) {
                spin_unlock_irqrestore(shost->host_lock, flags);
                if (!cancel_delayed_work(&rport->fail_io_work))
                        fc_flush_devloss(shost);
                if (!cancel_delayed_work(&rport->dev_loss_work))
                        fc_flush_devloss(shost);
                spin_lock_irqsave(shost->host_lock, flags);
                rport->flags &= ~FC_RPORT_DEVLOSS_PENDING;
        }
        spin_unlock_irqrestore(shost->host_lock, flags);

        /* Delete SCSI target and sdevs */
        if (rport->scsi_target_id != -1)
                fc_starget_delete(&rport->stgt_delete_work);

        /*
         * Notify the driver that the rport is now dead. The LLDD will
         * also guarantee that any communication to the rport is terminated
         */
        if (i->f->dev_loss_tmo_callbk)
                i->f->dev_loss_tmo_callbk(rport);

        transport_remove_device(dev);
        device_del(dev);
        transport_destroy_device(dev);
        put_device(&shost->shost_gendev);       /* for fc_host->rport list */
        put_device(dev);                        /* for self-reference */
}


/**
 * fc_rport_create - allocates and creates a remote FC port.
 * @shost:      scsi host the remote port is connected to.
 * @channel:    Channel on shost port connected to.
 * @ids:        The world wide names, fc address, and FC4 port
 *              roles for the remote port.
 *
 * Allocates and creates the remoter port structure, including the
 * class and sysfs creation.
 *
 * Notes:
 *      This routine assumes no locks are held on entry.
 */
static struct fc_rport *
fc_rport_create(struct Scsi_Host *shost, int channel,
        struct fc_rport_identifiers  *ids)
{
        struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
        struct fc_internal *fci = to_fc_internal(shost->transportt);
        struct fc_rport *rport;
        struct device *dev;
        unsigned long flags;
        int error;
        size_t size;

        size = (sizeof(struct fc_rport) + fci->f->dd_fcrport_size);
        rport = kzalloc(size, GFP_KERNEL);
        if (unlikely(!rport)) {
                printk(KERN_ERR "%s: allocation failure\n", __FUNCTION__);
                return NULL;
        }

        rport->maxframe_size = -1;
        rport->supported_classes = FC_COS_UNSPECIFIED;
        rport->dev_loss_tmo = fc_dev_loss_tmo;
        memcpy(&rport->node_name, &ids->node_name, sizeof(rport->node_name));
        memcpy(&rport->port_name, &ids->port_name, sizeof(rport->port_name));
        rport->port_id = ids->port_id;
        rport->roles = ids->roles;
        rport->port_state = FC_PORTSTATE_ONLINE;
        if (fci->f->dd_fcrport_size)
                rport->dd_data = &rport[1];
        rport->channel = channel;
        rport->fast_io_fail_tmo = -1;

        INIT_DELAYED_WORK(&rport->dev_loss_work, fc_timeout_deleted_rport);
        INIT_DELAYED_WORK(&rport->fail_io_work, fc_timeout_fail_rport_io);
        INIT_WORK(&rport->scan_work, fc_scsi_scan_rport);
        INIT_WORK(&rport->stgt_delete_work, fc_starget_delete);
        INIT_WORK(&rport->rport_delete_work, fc_rport_final_delete);

        spin_lock_irqsave(shost->host_lock, flags);

        rport->number = fc_host->next_rport_number++;
        if (rport->roles & FC_PORT_ROLE_FCP_TARGET)
                rport->scsi_target_id = fc_host->next_target_id++;
        else
                rport->scsi_target_id = -1;
        list_add_tail(&rport->peers, &fc_host->rports);
        get_device(&shost->shost_gendev);       /* for fc_host->rport list */

        spin_unlock_irqrestore(shost->host_lock, flags);

        dev = &rport->dev;
        device_initialize(dev);                 /* takes self reference */
        dev->parent = get_device(&shost->shost_gendev); /* parent reference */
        dev->release = fc_rport_dev_release;
        sprintf(dev->bus_id, "rport-%d:%d-%d",
                shost->host_no, channel, rport->number);
        transport_setup_device(dev);

        error = device_add(dev);
        if (error) {
                printk(KERN_ERR "FC Remote Port device_add failed\n");
                goto delete_rport;
        }
        transport_add_device(dev);
        transport_configure_device(dev);

        if (rport->roles & FC_PORT_ROLE_FCP_TARGET) {
                /* initiate a scan of the target */
                rport->flags |= FC_RPORT_SCAN_PENDING;
                scsi_queue_work(shost, &rport->scan_work);
        }

        return rport;

delete_rport:
        transport_destroy_device(dev);
        spin_lock_irqsave(shost->host_lock, flags);
        list_del(&rport->peers);
        put_device(&shost->shost_gendev);       /* for fc_host->rport list */
        spin_unlock_irqrestore(shost->host_lock, flags);
        put_device(dev->parent);
        kfree(rport);
        return NULL;
}

/**
 * fc_remote_port_add - notify fc transport of the existence of a remote FC port.
 * @shost:      scsi host the remote port is connected to.
 * @channel:    Channel on shost port connected to.
 * @ids:        The world wide names, fc address, and FC4 port
 *              roles for the remote port.
 *
 * The LLDD calls this routine to notify the transport of the existence
 * of a remote port. The LLDD provides the unique identifiers (wwpn,wwn)
 * of the port, it's FC address (port_id), and the FC4 roles that are
 * active for the port.
 *
 * For ports that are FCP targets (aka scsi targets), the FC transport
 * maintains consistent target id bindings on behalf of the LLDD.
 * A consistent target id binding is an assignment of a target id to
 * a remote port identifier, which persists while the scsi host is
 * attached. The remote port can disappear, then later reappear, and
 * it's target id assignment remains the same. This allows for shifts
 * in FC addressing (if binding by wwpn or wwnn) with no apparent
 * changes to the scsi subsystem which is based on scsi host number and
 * target id values.  Bindings are only valid during the attachment of
 * the scsi host. If the host detaches, then later re-attaches, target
 * id bindings may change.
 *
 * This routine is responsible for returning a remote port structure.
 * The routine will search the list of remote ports it maintains
 * internally on behalf of consistent target id mappings. If found, the
 * remote port structure will be reused. Otherwise, a new remote port
 * structure will be allocated.
 *
 * Whenever a remote port is allocated, a new fc_remote_port class
 * device is created.
 *
 * Should not be called from interrupt context.
 *
 * Notes:
 *      This routine assumes no locks are held on entry.
 */
struct fc_rport *
fc_remote_port_add(struct Scsi_Host *shost, int channel,
        struct fc_rport_identifiers  *ids)
{
        struct fc_internal *fci = to_fc_internal(shost->transportt);
        struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
        struct fc_rport *rport;
        unsigned long flags;
        int match = 0;

        /* ensure any stgt delete functions are done */
        fc_flush_work(shost);

        /*
         * Search the list of "active" rports, for an rport that has been
         * deleted, but we've held off the real delete while the target
         * is in a "blocked" state.
         */
        spin_lock_irqsave(shost->host_lock, flags);

        list_for_each_entry(rport, &fc_host->rports, peers) {

                if ((rport->port_state == FC_PORTSTATE_BLOCKED) &&
                        (rport->channel == channel)) {

                        switch (fc_host->tgtid_bind_type) {
                        case FC_TGTID_BIND_BY_WWPN:
                        case FC_TGTID_BIND_NONE:
                                if (rport->port_name == ids->port_name)
                                        match = 1;
                                break;
                        case FC_TGTID_BIND_BY_WWNN:
                                if (rport->node_name == ids->node_name)
                                        match = 1;
                                break;
                        case FC_TGTID_BIND_BY_ID:
                                if (rport->port_id == ids->port_id)
                                        match = 1;
                                break;
                        }

                        if (match) {

                                memcpy(&rport->node_name, &ids->node_name,
                                        sizeof(rport->node_name));
                                memcpy(&rport->port_name, &ids->port_name,
                                        sizeof(rport->port_name));
                                rport->port_id = ids->port_id;

                                rport->port_state = FC_PORTSTATE_ONLINE;
                                rport->roles = ids->roles;

                                spin_unlock_irqrestore(shost->host_lock, flags);

                                if (fci->f->dd_fcrport_size)
                                        memset(rport->dd_data, 0,
                                                fci->f->dd_fcrport_size);

                                /*
                                 * If we were not a target, cancel the
                                 * io terminate and rport timers, and
                                 * we're done.
                                 *
                                 * If we were a target, but our new role
                                 * doesn't indicate a target, leave the
                                 * timers running expecting the role to
                                 * change as the target fully logs in. If
                                 * it doesn't, the target will be torn down.
                                 *
                                 * If we were a target, and our role shows
                                 * we're still a target, cancel the timers
                                 * and kick off a scan.
                                 */

                                /* was a target, not in roles */
                                if ((rport->scsi_target_id != -1) &&
                                    (!(ids->roles & FC_PORT_ROLE_FCP_TARGET)))
                                        return rport;

                                /*
                                 * Stop the fail io and dev_loss timers.
                                 * If they flush, the port_state will
                                 * be checked and will NOOP the function.
                                 */
                                if (!cancel_delayed_work(&rport->fail_io_work))
                                        fc_flush_devloss(shost);
                                if (!cancel_delayed_work(&rport->dev_loss_work))
                                        fc_flush_devloss(shost);

                                spin_lock_irqsave(shost->host_lock, flags);

                                rport->flags &= ~FC_RPORT_DEVLOSS_PENDING;

                                /* if target, initiate a scan */
                                if (rport->scsi_target_id != -1) {
                                        rport->flags |= FC_RPORT_SCAN_PENDING;
                                        scsi_queue_work(shost,
                                                        &rport->scan_work);
                                        spin_unlock_irqrestore(shost->host_lock,
                                                        flags);
                                        scsi_target_unblock(&rport->dev);
                                } else
                                        spin_unlock_irqrestore(shost->host_lock,
                                                        flags);

                                return rport;
                        }
                }
        }

        /*
         * Search the bindings array
         * Note: if never a FCP target, you won't be on this list
         */
        if (fc_host->tgtid_bind_type != FC_TGTID_BIND_NONE) {

                /* search for a matching consistent binding */

                list_for_each_entry(rport, &fc_host->rport_bindings,
                                        peers) {
                        if (rport->channel != channel)
                                continue;

                        switch (fc_host->tgtid_bind_type) {
                        case FC_TGTID_BIND_BY_WWPN:
                                if (rport->port_name == ids->port_name)
                                        match = 1;
                                break;
                        case FC_TGTID_BIND_BY_WWNN:
                                if (rport->node_name == ids->node_name)
                                        match = 1;
                                break;
                        case FC_TGTID_BIND_BY_ID:
                                if (rport->port_id == ids->port_id)
                                        match = 1;
                                break;
                        case FC_TGTID_BIND_NONE: /* to keep compiler happy */
                                break;
                        }

                        if (match) {
                                list_move_tail(&rport->peers, &fc_host->rports);
                                break;
                        }
                }

                if (match) {
                        memcpy(&rport->node_name, &ids->node_name,
                                sizeof(rport->node_name));
                        memcpy(&rport->port_name, &ids->port_name,
                                sizeof(rport->port_name));
                        rport->port_id = ids->port_id;
                        rport->roles = ids->roles;
                        rport->port_state = FC_PORTSTATE_ONLINE;

                        if (fci->f->dd_fcrport_size)
                                memset(rport->dd_data, 0,
                                                fci->f->dd_fcrport_size);

                        if (rport->roles & FC_PORT_ROLE_FCP_TARGET) {
                                /* initiate a scan of the target */
                                rport->flags |= FC_RPORT_SCAN_PENDING;
                                scsi_queue_work(shost, &rport->scan_work);
                                spin_unlock_irqrestore(shost->host_lock, flags);
                                scsi_target_unblock(&rport->dev);
                        } else
                                spin_unlock_irqrestore(shost->host_lock, flags);

                        return rport;
                }
        }

        spin_unlock_irqrestore(shost->host_lock, flags);

        /* No consistent binding found - create new remote port entry */
        rport = fc_rport_create(shost, channel, ids);

        return rport;
}
EXPORT_SYMBOL(fc_remote_port_add);


/**
 * fc_remote_port_delete - notifies the fc transport that a remote port is no longer in existence.
 * @rport:      The remote port that no longer exists
 *
 * The LLDD calls this routine to notify the transport that a remote
 * port is no longer part of the topology. Note: Although a port
 * may no longer be part of the topology, it may persist in the remote
 * ports displayed by the fc_host. We do this under 2 conditions:
 * 1) If the port was a scsi target, we delay its deletion by "blocking" it.
 *   This allows the port to temporarily disappear, then reappear without
 *   disrupting the SCSI device tree attached to it. During the "blocked"
 *   period the port will still exist.
 * 2) If the port was a scsi target and disappears for longer than we
 *   expect, we'll delete the port and the tear down the SCSI device tree
 *   attached to it. However, we want to semi-persist the target id assigned
 *   to that port if it eventually does exist. The port structure will
 *   remain (although with minimal information) so that the target id
 *   bindings remails.
 *
 * If the remote port is not an FCP Target, it will be fully torn down
 * and deallocated, including the fc_remote_port class device.
 *
 * If the remote port is an FCP Target, the port will be placed in a
 * temporary blocked state. From the LLDD's perspective, the rport no
 * longer exists. From the SCSI midlayer's perspective, the SCSI target
 * exists, but all sdevs on it are blocked from further I/O. The following
 * is then expected.
 *
 *   If the remote port does not return (signaled by a LLDD call to
 *   fc_remote_port_add()) within the dev_loss_tmo timeout, then the
 *   scsi target is removed - killing all outstanding i/o and removing the
 *   scsi devices attached ot it. The port structure will be marked Not
 *   Present and be partially cleared, leaving only enough information to
 *   recognize the remote port relative to the scsi target id binding if
 *   it later appears.  The port will remain as long as there is a valid
 *   binding (e.g. until the user changes the binding type or unloads the
 *   scsi host with the binding).
 *
 *   If the remote port returns within the dev_loss_tmo value (and matches
 *   according to the target id binding type), the port structure will be
 *   reused. If it is no longer a SCSI target, the target will be torn
 *   down. If it continues to be a SCSI target, then the target will be
 *   unblocked (allowing i/o to be resumed), and a scan will be activated
 *   to ensure that all luns are detected.
 *
 * Called from normal process context only - cannot be called from interrupt.
 *
 * Notes:
 *      This routine assumes no locks are held on entry.
 */
void
fc_remote_port_delete(struct fc_rport  *rport)
{
        struct Scsi_Host *shost = rport_to_shost(rport);
        struct fc_internal *i = to_fc_internal(shost->transportt);
        int timeout = rport->dev_loss_tmo;
        unsigned long flags;

        /*
         * No need to flush the fc_host work_q's, as all adds are synchronous.
         *
         * We do need to reclaim the rport scan work element, so eventually
         * (in fc_rport_final_delete()) we'll flush the scsi host work_q if
         * there's still a scan pending.
         */

        spin_lock_irqsave(shost->host_lock, flags);

        if (rport->port_state != FC_PORTSTATE_ONLINE) {
                spin_unlock_irqrestore(shost->host_lock, flags);
                return;
        }

        /*
         * In the past, we if this was not an FCP-Target, we would
         * unconditionally just jump to deleting the rport.
         * However, rports can be used as node containers by the LLDD,
         * and its not appropriate to just terminate the rport at the
         * first sign of a loss in connectivity. The LLDD may want to
         * send ELS traffic to re-validate the login. If the rport is
         * immediately deleted, it makes it inappropriate for a node
         * container.
         * So... we now unconditionally wait dev_loss_tmo before
         * destroying an rport.
         */

        rport->port_state = FC_PORTSTATE_BLOCKED;

        rport->flags |= FC_RPORT_DEVLOSS_PENDING;

        spin_unlock_irqrestore(shost->host_lock, flags);

        if (rport->roles & FC_PORT_ROLE_FCP_INITIATOR &&
            shost->active_mode & MODE_TARGET)
                fc_tgt_it_nexus_destroy(shost, (unsigned long)rport);

        scsi_target_block(&rport->dev);

        /* see if we need to kill io faster than waiting for device loss */
        if ((rport->fast_io_fail_tmo != -1) &&
            (rport->fast_io_fail_tmo < timeout) && (i->f->terminate_rport_io))
                fc_queue_devloss_work(shost, &rport->fail_io_work,
                                        rport->fast_io_fail_tmo * HZ);

        /* cap the length the devices can be blocked until they are deleted */
        fc_queue_devloss_work(shost, &rport->dev_loss_work, timeout * HZ);
}
EXPORT_SYMBOL(fc_remote_port_delete);

/**
 * fc_remote_port_rolechg - notifies the fc transport that the roles on a remote may have changed.
 * @rport:      The remote port that changed.
 * @roles:      New roles for this port.
 *
 * Description: The LLDD calls this routine to notify the transport that the
 * roles on a remote port may have changed. The largest effect of this is
 * if a port now becomes a FCP Target, it must be allocated a
 * scsi target id.  If the port is no longer a FCP target, any
 * scsi target id value assigned to it will persist in case the
 * role changes back to include FCP Target. No changes in the scsi
 * midlayer will be invoked if the role changes (in the expectation
 * that the role will be resumed. If it doesn't normal error processing
 * will take place).
 *
 * Should not be called from interrupt context.
 *
 * Notes:
 *      This routine assumes no locks are held on entry.
 */
void
fc_remote_port_rolechg(struct fc_rport  *rport, u32 roles)
{
        struct Scsi_Host *shost = rport_to_shost(rport);
        struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
        unsigned long flags;
        int create = 0;
        int ret;

        spin_lock_irqsave(shost->host_lock, flags);
        if (roles & FC_PORT_ROLE_FCP_TARGET) {
                if (rport->scsi_target_id == -1) {
                        rport->scsi_target_id = fc_host->next_target_id++;
                        create = 1;
                } else if (!(rport->roles & FC_PORT_ROLE_FCP_TARGET))
                        create = 1;
        } else if (shost->active_mode & MODE_TARGET) {
                ret = fc_tgt_it_nexus_create(shost, (unsigned long)rport,
                                             (char *)&rport->node_name);
                if (ret)
                        printk(KERN_ERR "FC Remore Port tgt nexus failed %d\n",
                               ret);
        }

        rport->roles = roles;

        spin_unlock_irqrestore(shost->host_lock, flags);

        if (create) {
                /*
                 * There may have been a delete timer running on the
                 * port. Ensure that it is cancelled as we now know
                 * the port is an FCP Target.
                 * Note: we know the rport is exists and in an online
                 *  state as the LLDD would not have had an rport
                 *  reference to pass us.
                 *
                 * Take no action on the del_timer failure as the state
                 * machine state change will validate the
                 * transaction.
                 */
                if (!cancel_delayed_work(&rport->fail_io_work))
                        fc_flush_devloss(shost);
                if (!cancel_delayed_work(&rport->dev_loss_work))
                        fc_flush_devloss(shost);

                spin_lock_irqsave(shost->host_lock, flags);
                rport->flags &= ~FC_RPORT_DEVLOSS_PENDING;
                spin_unlock_irqrestore(shost->host_lock, flags);

                /* ensure any stgt delete functions are done */
                fc_flush_work(shost);

                /* initiate a scan of the target */
                spin_lock_irqsave(shost->host_lock, flags);
                rport->flags |= FC_RPORT_SCAN_PENDING;
                scsi_queue_work(shost, &rport->scan_work);
                spin_unlock_irqrestore(shost->host_lock, flags);
                scsi_target_unblock(&rport->dev);
        }
}
EXPORT_SYMBOL(fc_remote_port_rolechg);

/**
 * fc_timeout_deleted_rport - Timeout handler for a deleted remote port.
 * @work:       rport target that failed to reappear in the allotted time.
 *
 * Description: An attempt to delete a remote port blocks, and if it fails
 *              to return in the allotted time this gets called.
 */
static void
fc_timeout_deleted_rport(struct work_struct *work)
{
        struct fc_rport *rport =
                container_of(work, struct fc_rport, dev_loss_work.work);
        struct Scsi_Host *shost = rport_to_shost(rport);
        struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
        unsigned long flags;

        spin_lock_irqsave(shost->host_lock, flags);

        rport->flags &= ~FC_RPORT_DEVLOSS_PENDING;

        /*
         * If the port is ONLINE, then it came back. If it was a SCSI
         * target, validate it still is. If not, tear down the
         * scsi_target on it.
         */
        if ((rport->port_state == FC_PORTSTATE_ONLINE) &&
            (rport->scsi_target_id != -1) &&
            !(rport->roles & FC_PORT_ROLE_FCP_TARGET)) {
                dev_printk(KERN_ERR, &rport->dev,
                        "blocked FC remote port time out: no longer"
                        " a FCP target, removing starget\n");
                spin_unlock_irqrestore(shost->host_lock, flags);
                scsi_target_unblock(&rport->dev);
                fc_queue_work(shost, &rport->stgt_delete_work);
                return;
        }

        /* NOOP state - we're flushing workq's */
        if (rport->port_state != FC_PORTSTATE_BLOCKED) {
                spin_unlock_irqrestore(shost->host_lock, flags);
                dev_printk(KERN_ERR, &rport->dev,
                        "blocked FC remote port time out: leaving"
                        " rport%s alone\n",
                        (rport->scsi_target_id != -1) ?  " and starget" : "");
                return;
        }

        if ((fc_host->tgtid_bind_type == FC_TGTID_BIND_NONE) ||
            (rport->scsi_target_id == -1)) {
                list_del(&rport->peers);
                rport->port_state = FC_PORTSTATE_DELETED;
                dev_printk(KERN_ERR, &rport->dev,
                        "blocked FC remote port time out: removing"
                        " rport%s\n",
                        (rport->scsi_target_id != -1) ?  " and starget" : "");
                fc_queue_work(shost, &rport->rport_delete_work);
                spin_unlock_irqrestore(shost->host_lock, flags);
                return;
        }

        dev_printk(KERN_ERR, &rport->dev,
                "blocked FC remote port time out: removing target and "
                "saving binding\n");

        list_move_tail(&rport->peers, &fc_host->rport_bindings);

        /*
         * Note: We do not remove or clear the hostdata area. This allows
         *   host-specific target data to persist along with the
         *   scsi_target_id. It's up to the host to manage it's hostdata area.
         */

        /*
         * Reinitialize port attributes that may change if the port comes back.
         */
        rport->maxframe_size = -1;
        rport->supported_classes = FC_COS_UNSPECIFIED;
        rport->roles = FC_PORT_ROLE_UNKNOWN;
        rport->port_state = FC_PORTSTATE_NOTPRESENT;

        /* remove the identifiers that aren't used in the consisting binding */
        switch (fc_host->tgtid_bind_type) {
        case FC_TGTID_BIND_BY_WWPN:
                rport->node_name = -1;
                rport->port_id = -1;
                break;
        case FC_TGTID_BIND_BY_WWNN:
                rport->port_name = -1;
                rport->port_id = -1;
                break;
        case FC_TGTID_BIND_BY_ID:
                rport->node_name = -1;
                rport->port_name = -1;
                break;
        case FC_TGTID_BIND_NONE:        /* to keep compiler happy */
                break;
        }

        /*
         * As this only occurs if the remote port (scsi target)
         * went away and didn't come back - we'll remove
         * all attached scsi devices.
         */
        spin_unlock_irqrestore(shost->host_lock, flags);

        scsi_target_unblock(&rport->dev);
        fc_queue_work(shost, &rport->stgt_delete_work);
}

/**
 * fc_timeout_fail_rport_io - Timeout handler for a fast io failing on a disconnected SCSI target.
 * @work:       rport to terminate io on.
 *
 * Notes: Only requests the failure of the io, not that all are flushed
 *    prior to returning.
 */
static void
fc_timeout_fail_rport_io(struct work_struct *work)
{
        struct fc_rport *rport =
                container_of(work, struct fc_rport, fail_io_work.work);
        struct Scsi_Host *shost = rport_to_shost(rport);
        struct fc_internal *i = to_fc_internal(shost->transportt);

        if (rport->port_state != FC_PORTSTATE_BLOCKED)
                return;

        i->f->terminate_rport_io(rport);
}

/**
 * fc_scsi_scan_rport - called to perform a scsi scan on a remote port.
 * @work:       remote port to be scanned.
 */
static void
fc_scsi_scan_rport(struct work_struct *work)
{
        struct fc_rport *rport =
                container_of(work, struct fc_rport, scan_work);
        struct Scsi_Host *shost = rport_to_shost(rport);
        struct fc_internal *i = to_fc_internal(shost->transportt);
        unsigned long flags;

        if ((rport->port_state == FC_PORTSTATE_ONLINE) &&
            (rport->roles & FC_PORT_ROLE_FCP_TARGET) &&
            !(i->f->disable_target_scan)) {
                scsi_scan_target(&rport->dev, rport->channel,
                        rport->scsi_target_id, SCAN_WILD_CARD, 1);
        }

        spin_lock_irqsave(shost->host_lock, flags);
        rport->flags &= ~FC_RPORT_SCAN_PENDING;
        spin_unlock_irqrestore(shost->host_lock, flags);
}


/**
 * fc_vport_create - allocates and creates a FC virtual port.
 * @shost:      scsi host the virtual port is connected to.
 * @channel:    Channel on shost port connected to.
 * @pdev:       parent device for vport
 * @ids:        The world wide names, FC4 port roles, etc for
 *              the virtual port.
 * @ret_vport:  The pointer to the created vport.
 *
 * Allocates and creates the vport structure, calls the parent host
 * to instantiate the vport, the completes w/ class and sysfs creation.
 *
 * Notes:
 *      This routine assumes no locks are held on entry.
 */
static int
fc_vport_create(struct Scsi_Host *shost, int channel, struct device *pdev,
        struct fc_vport_identifiers  *ids, struct fc_vport **ret_vport)
{
        struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
        struct fc_internal *fci = to_fc_internal(shost->transportt);
        struct fc_vport *vport;
        struct device *dev;
        unsigned long flags;
        size_t size;
        int error;

        *ret_vport = NULL;

        if ( ! fci->f->vport_create)
                return -ENOENT;

        size = (sizeof(struct fc_vport) + fci->f->dd_fcvport_size);
        vport = kzalloc(size, GFP_KERNEL);
        if (unlikely(!vport)) {
                printk(KERN_ERR "%s: allocation failure\n", __FUNCTION__);
                return -ENOMEM;
        }

        vport->vport_state = FC_VPORT_UNKNOWN;
        vport->vport_last_state = FC_VPORT_UNKNOWN;
        vport->node_name = ids->node_name;
        vport->port_name = ids->port_name;
        vport->roles = ids->roles;
        vport->vport_type = ids->vport_type;
        if (fci->f->dd_fcvport_size)
                vport->dd_data = &vport[1];
        vport->shost = shost;
        vport->channel = channel;
        vport->flags = FC_VPORT_CREATING;
        INIT_WORK(&vport->vport_delete_work, fc_vport_sched_delete);

        spin_lock_irqsave(shost->host_lock, flags);

        if (fc_host->npiv_vports_inuse >= fc_host->max_npiv_vports) {
                spin_unlock_irqrestore(shost->host_lock, flags);
                kfree(vport);
                return -ENOSPC;
        }
        fc_host->npiv_vports_inuse++;
        vport->number = fc_host->next_vport_number++;
        list_add_tail(&vport->peers, &fc_host->vports);
        get_device(&shost->shost_gendev);       /* for fc_host->vport list */

        spin_unlock_irqrestore(shost->host_lock, flags);

        dev = &vport->dev;
        device_initialize(dev);                 /* takes self reference */
        dev->parent = get_device(pdev);         /* takes parent reference */
        dev->release = fc_vport_dev_release;
        sprintf(dev->bus_id, "vport-%d:%d-%d",
                shost->host_no, channel, vport->number);
        transport_setup_device(dev);

        error = device_add(dev);
        if (error) {
                printk(KERN_ERR "FC Virtual Port device_add failed\n");
                goto delete_vport;
        }
        transport_add_device(dev);
        transport_configure_device(dev);

        error = fci->f->vport_create(vport, ids->disable);
        if (error) {
                printk(KERN_ERR "FC Virtual Port LLDD Create failed\n");
                goto delete_vport_all;
        }

        /*
         * if the parent isn't the physical adapter's Scsi_Host, ensure
         * the Scsi_Host at least contains ia symlink to the vport.
         */
        if (pdev != &shost->shost_gendev) {
                error = sysfs_create_link(&shost->shost_gendev.kobj,
                                 &dev->kobj, dev->bus_id);
                if (error)
                        printk(KERN_ERR
                                "%s: Cannot create vport symlinks for "
                                "%s, err=%d\n",
                                __FUNCTION__, dev->bus_id, error);
        }
        spin_lock_irqsave(shost->host_lock, flags);
        vport->flags &= ~FC_VPORT_CREATING;
        spin_unlock_irqrestore(shost->host_lock, flags);

        dev_printk(KERN_NOTICE, pdev,
                        "%s created via shost%d channel %d\n", dev->bus_id,
                        shost->host_no, channel);

        *ret_vport = vport;

        return 0;

delete_vport_all:
        transport_remove_device(dev);
        device_del(dev);
delete_vport:
        transport_destroy_device(dev);
        spin_lock_irqsave(shost->host_lock, flags);
        list_del(&vport->peers);
        put_device(&shost->shost_gendev);       /* for fc_host->vport list */
        fc_host->npiv_vports_inuse--;
        spin_unlock_irqrestore(shost->host_lock, flags);
        put_device(dev->parent);
        kfree(vport);

        return error;
}


/**
 * fc_vport_terminate - Admin App or LLDD requests termination of a vport
 * @vport:      fc_vport to be terminated
 *
 * Calls the LLDD vport_delete() function, then deallocates and removes
 * the vport from the shost and object tree.
 *
 * Notes:
 *      This routine assumes no locks are held on entry.
 */
int
fc_vport_terminate(struct fc_vport *vport)
{
        struct Scsi_Host *shost = vport_to_shost(vport);
        struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
        struct fc_internal *i = to_fc_internal(shost->transportt);
        struct device *dev = &vport->dev;
        unsigned long flags;
        int stat;

        spin_lock_irqsave(shost->host_lock, flags);
        if (vport->flags & FC_VPORT_CREATING) {
                spin_unlock_irqrestore(shost->host_lock, flags);
                return -EBUSY;
        }
        if (vport->flags & (FC_VPORT_DEL)) {
                spin_unlock_irqrestore(shost->host_lock, flags);
                return -EALREADY;
        }
        vport->flags |= FC_VPORT_DELETING;
        spin_unlock_irqrestore(shost->host_lock, flags);

        if (i->f->vport_delete)
                stat = i->f->vport_delete(vport);
        else
                stat = -ENOENT;

        spin_lock_irqsave(shost->host_lock, flags);
        vport->flags &= ~FC_VPORT_DELETING;
        if (!stat) {
                vport->flags |= FC_VPORT_DELETED;
                list_del(&vport->peers);
                fc_host->npiv_vports_inuse--;
                put_device(&shost->shost_gendev);  /* for fc_host->vport list */
        }
        spin_unlock_irqrestore(shost->host_lock, flags);

        if (stat)
                return stat;

        if (dev->parent != &shost->shost_gendev)
                sysfs_remove_link(&shost->shost_gendev.kobj, dev->bus_id);
        transport_remove_device(dev);
        device_del(dev);
        transport_destroy_device(dev);

        /*
         * Removing our self-reference should mean our
         * release function gets called, which will drop the remaining
         * parent reference and free the data structure.
         */
        put_device(dev);                        /* for self-reference */

        return 0; /* SUCCESS */
}
EXPORT_SYMBOL(fc_vport_terminate);

/**
 * fc_vport_sched_delete - workq-based delete request for a vport
 * @work:       vport to be deleted.
 */
static void
fc_vport_sched_delete(struct work_struct *work)
{
        struct fc_vport *vport =
                container_of(work, struct fc_vport, vport_delete_work);
        int stat;

        stat = fc_vport_terminate(vport);
        if (stat)
                dev_printk(KERN_ERR, vport->dev.parent,
                        "%s: %s could not be deleted created via "
                        "shost%d channel %d - error %d\n", __FUNCTION__,
                        vport->dev.bus_id, vport->shost->host_no,
                        vport->channel, stat);
}


/* Original Author:  Martin Hicks */
MODULE_AUTHOR("James Smart");
MODULE_DESCRIPTION("FC Transport Attributes");
MODULE_LICENSE("GPL");

module_init(fc_transport_init);
module_exit(fc_transport_exit);