zfcp_fc.c

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/*
 * zfcp device driver
 *
 * Fibre Channel related functions for the zfcp device driver.
 *
 * Copyright IBM Corp. 2008, 2010
 */

#define KMSG_COMPONENT "zfcp"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/types.h>
#include <linux/slab.h>
#include <linux/utsname.h>
#include <scsi/fc/fc_els.h>
#include <scsi/libfc.h>
#include "zfcp_ext.h"
#include "zfcp_fc.h"

struct kmem_cache *zfcp_fc_req_cache;

static u32 zfcp_fc_rscn_range_mask[] = {
    [ELS_ADDR_FMT_PORT]     = 0xFFFFFF,
    [ELS_ADDR_FMT_AREA]     = 0xFFFF00,
    [ELS_ADDR_FMT_DOM]      = 0xFF0000,
    [ELS_ADDR_FMT_FAB]      = 0x000000,
};

static bool no_auto_port_rescan;
module_param_named(no_auto_port_rescan, no_auto_port_rescan, bool, 0600);
MODULE_PARM_DESC(no_auto_port_rescan,
         "no automatic port_rescan (default off)");

void zfcp_fc_conditional_port_scan(struct zfcp_adapter *adapter)
{
    if (no_auto_port_rescan)
        return;

    queue_work(adapter->work_queue, &adapter->scan_work);
}

void zfcp_fc_inverse_conditional_port_scan(struct zfcp_adapter *adapter)
{
    if (!no_auto_port_rescan)
        return;

    queue_work(adapter->work_queue, &adapter->scan_work);
}

void zfcp_fc_post_event(struct work_struct *work)
{
    struct zfcp_fc_event *event = NULL, *tmp = NULL;
    LIST_HEAD(tmp_lh);
    struct zfcp_fc_events *events = container_of(work,
                    struct zfcp_fc_events, work);
    struct zfcp_adapter *adapter = container_of(events, struct zfcp_adapter,
                        events);

    spin_lock_bh(&events->list_lock);
    list_splice_init(&events->list, &tmp_lh);
    spin_unlock_bh(&events->list_lock);

    list_for_each_entry_safe(event, tmp, &tmp_lh, list) {
        fc_host_post_event(adapter->scsi_host, fc_get_event_number(),
                event->code, event->data);
        list_del(&event->list);
        kfree(event);
    }

}

void zfcp_fc_enqueue_event(struct zfcp_adapter *adapter,
            enum fc_host_event_code event_code, u32 event_data)
{
    struct zfcp_fc_event *event;

    event = kmalloc(sizeof(struct zfcp_fc_event), GFP_ATOMIC);
    if (!event)
        return;

    event->code = event_code;
    event->data = event_data;

    spin_lock(&adapter->events.list_lock);
    list_add_tail(&event->list, &adapter->events.list);
    spin_unlock(&adapter->events.list_lock);

    queue_work(adapter->work_queue, &adapter->events.work);
}

static int zfcp_fc_wka_port_get(struct zfcp_fc_wka_port *wka_port)
{
    if (mutex_lock_interruptible(&wka_port->mutex))
        return -ERESTARTSYS;

    if (wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE ||
        wka_port->status == ZFCP_FC_WKA_PORT_CLOSING) {
        wka_port->status = ZFCP_FC_WKA_PORT_OPENING;
        if (zfcp_fsf_open_wka_port(wka_port))
            wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
    }

    mutex_unlock(&wka_port->mutex);

    wait_event(wka_port->completion_wq,
           wka_port->status == ZFCP_FC_WKA_PORT_ONLINE ||
           wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE);

    if (wka_port->status == ZFCP_FC_WKA_PORT_ONLINE) {
        atomic_inc(&wka_port->refcount);
        return 0;
    }
    return -EIO;
}

static void zfcp_fc_wka_port_offline(struct work_struct *work)
{
    struct delayed_work *dw = to_delayed_work(work);
    struct zfcp_fc_wka_port *wka_port =
            container_of(dw, struct zfcp_fc_wka_port, work);

    mutex_lock(&wka_port->mutex);
    if ((atomic_read(&wka_port->refcount) != 0) ||
        (wka_port->status != ZFCP_FC_WKA_PORT_ONLINE))
        goto out;

    wka_port->status = ZFCP_FC_WKA_PORT_CLOSING;
    if (zfcp_fsf_close_wka_port(wka_port)) {
        wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
        wake_up(&wka_port->completion_wq);
    }
out:
    mutex_unlock(&wka_port->mutex);
}

static void zfcp_fc_wka_port_put(struct zfcp_fc_wka_port *wka_port)
{
    if (atomic_dec_return(&wka_port->refcount) != 0)
        return;
    /* wait 10 milliseconds, other reqs might pop in */
    schedule_delayed_work(&wka_port->work, HZ / 100);
}

static void zfcp_fc_wka_port_init(struct zfcp_fc_wka_port *wka_port, u32 d_id,
                  struct zfcp_adapter *adapter)
{
    init_waitqueue_head(&wka_port->completion_wq);

    wka_port->adapter = adapter;
    wka_port->d_id = d_id;

    wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
    atomic_set(&wka_port->refcount, 0);
    mutex_init(&wka_port->mutex);
    INIT_DELAYED_WORK(&wka_port->work, zfcp_fc_wka_port_offline);
}

static void zfcp_fc_wka_port_force_offline(struct zfcp_fc_wka_port *wka)
{
    cancel_delayed_work_sync(&wka->work);
    mutex_lock(&wka->mutex);
    wka->status = ZFCP_FC_WKA_PORT_OFFLINE;
    mutex_unlock(&wka->mutex);
}

void zfcp_fc_wka_ports_force_offline(struct zfcp_fc_wka_ports *gs)
{
    if (!gs)
        return;
    zfcp_fc_wka_port_force_offline(&gs->ms);
    zfcp_fc_wka_port_force_offline(&gs->ts);
    zfcp_fc_wka_port_force_offline(&gs->ds);
    zfcp_fc_wka_port_force_offline(&gs->as);
}

static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
                   struct fc_els_rscn_page *page)
{
    unsigned long flags;
    struct zfcp_adapter *adapter = fsf_req->adapter;
    struct zfcp_port *port;

    read_lock_irqsave(&adapter->port_list_lock, flags);
    list_for_each_entry(port, &adapter->port_list, list) {
        if ((port->d_id & range) == (ntoh24(page->rscn_fid) & range))
            zfcp_fc_test_link(port);
        if (!port->d_id)
            zfcp_erp_port_reopen(port,
                         ZFCP_STATUS_COMMON_ERP_FAILED,
                         "fcrscn1");
    }
    read_unlock_irqrestore(&adapter->port_list_lock, flags);
}

static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
{
    struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
    struct fc_els_rscn *head;
    struct fc_els_rscn_page *page;
    u16 i;
    u16 no_entries;
    unsigned int afmt;

    head = (struct fc_els_rscn *) status_buffer->payload.data;
    page = (struct fc_els_rscn_page *) head;

    /* see FC-FS */
    no_entries = head->rscn_plen / sizeof(struct fc_els_rscn_page);

    for (i = 1; i < no_entries; i++) {
        /* skip head and start with 1st element */
        page++;
        afmt = page->rscn_page_flags & ELS_RSCN_ADDR_FMT_MASK;
        _zfcp_fc_incoming_rscn(fsf_req, zfcp_fc_rscn_range_mask[afmt],
                       page);
        zfcp_fc_enqueue_event(fsf_req->adapter, FCH_EVT_RSCN,
                      *(u32 *)page);
    }
    zfcp_fc_conditional_port_scan(fsf_req->adapter);
}

static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
{
    unsigned long flags;
    struct zfcp_adapter *adapter = req->adapter;
    struct zfcp_port *port;

    read_lock_irqsave(&adapter->port_list_lock, flags);
    list_for_each_entry(port, &adapter->port_list, list)
        if (port->wwpn == wwpn) {
            zfcp_erp_port_forced_reopen(port, 0, "fciwwp1");
            break;
        }
    read_unlock_irqrestore(&adapter->port_list_lock, flags);
}

static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
{
    struct fsf_status_read_buffer *status_buffer;
    struct fc_els_flogi *plogi;

    status_buffer = (struct fsf_status_read_buffer *) req->data;
    plogi = (struct fc_els_flogi *) status_buffer->payload.data;
    zfcp_fc_incoming_wwpn(req, plogi->fl_wwpn);
}

static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
{
    struct fsf_status_read_buffer *status_buffer =
        (struct fsf_status_read_buffer *)req->data;
    struct fc_els_logo *logo =
        (struct fc_els_logo *) status_buffer->payload.data;

    zfcp_fc_incoming_wwpn(req, logo->fl_n_port_wwn);
}

void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
{
    struct fsf_status_read_buffer *status_buffer =
        (struct fsf_status_read_buffer *) fsf_req->data;
    unsigned int els_type = status_buffer->payload.data[0];

    zfcp_dbf_san_in_els("fciels1", fsf_req);
    if (els_type == ELS_PLOGI)
        zfcp_fc_incoming_plogi(fsf_req);
    else if (els_type == ELS_LOGO)
        zfcp_fc_incoming_logo(fsf_req);
    else if (els_type == ELS_RSCN)
        zfcp_fc_incoming_rscn(fsf_req);
}

static void zfcp_fc_ns_gid_pn_eval(struct zfcp_fc_req *fc_req)
{
    struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
    struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;

    if (ct_els->status)
        return;
    if (gid_pn_rsp->ct_hdr.ct_cmd != FC_FS_ACC)
        return;

    /* looks like a valid d_id */
    ct_els->port->d_id = ntoh24(gid_pn_rsp->gid_pn.fp_fid);
}

static void zfcp_fc_complete(void *data)
{
    complete(data);
}

static void zfcp_fc_ct_ns_init(struct fc_ct_hdr *ct_hdr, u16 cmd, u16 mr_size)
{
    ct_hdr->ct_rev = FC_CT_REV;
    ct_hdr->ct_fs_type = FC_FST_DIR;
    ct_hdr->ct_fs_subtype = FC_NS_SUBTYPE;
    ct_hdr->ct_cmd = cmd;
    ct_hdr->ct_mr_size = mr_size / 4;
}

static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port,
                     struct zfcp_fc_req *fc_req)
{
    struct zfcp_adapter *adapter = port->adapter;
    DECLARE_COMPLETION_ONSTACK(completion);
    struct zfcp_fc_gid_pn_req *gid_pn_req = &fc_req->u.gid_pn.req;
    struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
    int ret;

    /* setup parameters for send generic command */
    fc_req->ct_els.port = port;
    fc_req->ct_els.handler = zfcp_fc_complete;
    fc_req->ct_els.handler_data = &completion;
    fc_req->ct_els.req = &fc_req->sg_req;
    fc_req->ct_els.resp = &fc_req->sg_rsp;
    sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req));
    sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp));

    zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr,
               FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE);
    gid_pn_req->gid_pn.fn_wwpn = port->wwpn;

    ret = zfcp_fsf_send_ct(&adapter->gs->ds, &fc_req->ct_els,
                   adapter->pool.gid_pn_req,
                   ZFCP_FC_CTELS_TMO);
    if (!ret) {
        wait_for_completion(&completion);
        zfcp_fc_ns_gid_pn_eval(fc_req);
    }
    return ret;
}

static int zfcp_fc_ns_gid_pn(struct zfcp_port *port)
{
    int ret;
    struct zfcp_fc_req *fc_req;
    struct zfcp_adapter *adapter = port->adapter;

    fc_req = mempool_alloc(adapter->pool.gid_pn, GFP_ATOMIC);
    if (!fc_req)
        return -ENOMEM;

    memset(fc_req, 0, sizeof(*fc_req));

    ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
    if (ret)
        goto out;

    ret = zfcp_fc_ns_gid_pn_request(port, fc_req);

    zfcp_fc_wka_port_put(&adapter->gs->ds);
out:
    mempool_free(fc_req, adapter->pool.gid_pn);
    return ret;
}

void zfcp_fc_port_did_lookup(struct work_struct *work)
{
    int ret;
    struct zfcp_port *port = container_of(work, struct zfcp_port,
                          gid_pn_work);

    ret = zfcp_fc_ns_gid_pn(port);
    if (ret) {
        /* could not issue gid_pn for some reason */
        zfcp_erp_adapter_reopen(port->adapter, 0, "fcgpn_1");
        goto out;
    }

    if (!port->d_id) {
        zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED);
        goto out;
    }

    zfcp_erp_port_reopen(port, 0, "fcgpn_3");
out:
    put_device(&port->dev);
}

void zfcp_fc_trigger_did_lookup(struct zfcp_port *port)
{
    get_device(&port->dev);
    if (!queue_work(port->adapter->work_queue, &port->gid_pn_work))
        put_device(&port->dev);
}

void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fc_els_flogi *plogi)
{
    if (plogi->fl_wwpn != port->wwpn) {
        port->d_id = 0;
        dev_warn(&port->adapter->ccw_device->dev,
             "A port opened with WWPN 0x%016Lx returned data that "
             "identifies it as WWPN 0x%016Lx\n",
             (unsigned long long) port->wwpn,
             (unsigned long long) plogi->fl_wwpn);
        return;
    }

    port->wwnn = plogi->fl_wwnn;
    port->maxframe_size = plogi->fl_csp.sp_bb_data;

    if (plogi->fl_cssp[0].cp_class & FC_CPC_VALID)
        port->supported_classes |= FC_COS_CLASS1;
    if (plogi->fl_cssp[1].cp_class & FC_CPC_VALID)
        port->supported_classes |= FC_COS_CLASS2;
    if (plogi->fl_cssp[2].cp_class & FC_CPC_VALID)
        port->supported_classes |= FC_COS_CLASS3;
    if (plogi->fl_cssp[3].cp_class & FC_CPC_VALID)
        port->supported_classes |= FC_COS_CLASS4;
}

static void zfcp_fc_adisc_handler(void *data)
{
    struct zfcp_fc_req *fc_req = data;
    struct zfcp_port *port = fc_req->ct_els.port;
    struct fc_els_adisc *adisc_resp = &fc_req->u.adisc.rsp;

    if (fc_req->ct_els.status) {
        /* request rejected or timed out */
        zfcp_erp_port_forced_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
                        "fcadh_1");
        goto out;
    }

    if (!port->wwnn)
        port->wwnn = adisc_resp->adisc_wwnn;

    if ((port->wwpn != adisc_resp->adisc_wwpn) ||
        !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
        zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
                     "fcadh_2");
        goto out;
    }

    /* port is good, unblock rport without going through erp */
    zfcp_scsi_schedule_rport_register(port);
 out:
    atomic_clear_mask(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
    put_device(&port->dev);
    kmem_cache_free(zfcp_fc_req_cache, fc_req);
}

static int zfcp_fc_adisc(struct zfcp_port *port)
{
    struct zfcp_fc_req *fc_req;
    struct zfcp_adapter *adapter = port->adapter;
    struct Scsi_Host *shost = adapter->scsi_host;
    int ret;

    fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_ATOMIC);
    if (!fc_req)
        return -ENOMEM;

    fc_req->ct_els.port = port;
    fc_req->ct_els.req = &fc_req->sg_req;
    fc_req->ct_els.resp = &fc_req->sg_rsp;
    sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req,
            sizeof(struct fc_els_adisc));
    sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp,
            sizeof(struct fc_els_adisc));

    fc_req->ct_els.handler = zfcp_fc_adisc_handler;
    fc_req->ct_els.handler_data = fc_req;

    /* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
       without FC-AL-2 capability, so we don't set it */
    fc_req->u.adisc.req.adisc_wwpn = fc_host_port_name(shost);
    fc_req->u.adisc.req.adisc_wwnn = fc_host_node_name(shost);
    fc_req->u.adisc.req.adisc_cmd = ELS_ADISC;
    hton24(fc_req->u.adisc.req.adisc_port_id, fc_host_port_id(shost));

    ret = zfcp_fsf_send_els(adapter, port->d_id, &fc_req->ct_els,
                ZFCP_FC_CTELS_TMO);
    if (ret)
        kmem_cache_free(zfcp_fc_req_cache, fc_req);

    return ret;
}

void zfcp_fc_link_test_work(struct work_struct *work)
{
    struct zfcp_port *port =
        container_of(work, struct zfcp_port, test_link_work);
    int retval;

    get_device(&port->dev);
    port->rport_task = RPORT_DEL;
    zfcp_scsi_rport_work(&port->rport_work);

    /* only issue one test command at one time per port */
    if (atomic_read(&port->status) & ZFCP_STATUS_PORT_LINK_TEST)
        goto out;

    atomic_set_mask(ZFCP_STATUS_PORT_LINK_TEST, &port->status);

    retval = zfcp_fc_adisc(port);
    if (retval == 0)
        return;

    /* send of ADISC was not possible */
    atomic_clear_mask(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
    zfcp_erp_port_forced_reopen(port, 0, "fcltwk1");

out:
    put_device(&port->dev);
}

void zfcp_fc_test_link(struct zfcp_port *port)
{
    get_device(&port->dev);
    if (!queue_work(port->adapter->work_queue, &port->test_link_work))
        put_device(&port->dev);
}

static struct zfcp_fc_req *zfcp_alloc_sg_env(int buf_num)
{
    struct zfcp_fc_req *fc_req;

    fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
    if (!fc_req)
        return NULL;

    if (zfcp_sg_setup_table(&fc_req->sg_rsp, buf_num)) {
        kmem_cache_free(zfcp_fc_req_cache, fc_req);
        return NULL;
    }

    sg_init_one(&fc_req->sg_req, &fc_req->u.gpn_ft.req,
            sizeof(struct zfcp_fc_gpn_ft_req));

    return fc_req;
}

static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req,
                   struct zfcp_adapter *adapter, int max_bytes)
{
    struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
    struct zfcp_fc_gpn_ft_req *req = &fc_req->u.gpn_ft.req;
    DECLARE_COMPLETION_ONSTACK(completion);
    int ret;

    zfcp_fc_ct_ns_init(&req->ct_hdr, FC_NS_GPN_FT, max_bytes);
    req->gpn_ft.fn_fc4_type = FC_TYPE_FCP;

    ct_els->handler = zfcp_fc_complete;
    ct_els->handler_data = &completion;
    ct_els->req = &fc_req->sg_req;
    ct_els->resp = &fc_req->sg_rsp;

    ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
                   ZFCP_FC_CTELS_TMO);
    if (!ret)
        wait_for_completion(&completion);
    return ret;
}

static void zfcp_fc_validate_port(struct zfcp_port *port, struct list_head *lh)
{
    if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC))
        return;

    atomic_clear_mask(ZFCP_STATUS_COMMON_NOESC, &port->status);

    if ((port->supported_classes != 0) ||
        !list_empty(&port->unit_list))
        return;

    list_move_tail(&port->list, lh);
}

static int zfcp_fc_eval_gpn_ft(struct zfcp_fc_req *fc_req,
                   struct zfcp_adapter *adapter, int max_entries)
{
    struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
    struct scatterlist *sg = &fc_req->sg_rsp;
    struct fc_ct_hdr *hdr = sg_virt(sg);
    struct fc_gpn_ft_resp *acc = sg_virt(sg);
    struct zfcp_port *port, *tmp;
    unsigned long flags;
    LIST_HEAD(remove_lh);
    u32 d_id;
    int ret = 0, x, last = 0;

    if (ct_els->status)
        return -EIO;

    if (hdr->ct_cmd != FC_FS_ACC) {
        if (hdr->ct_reason == FC_BA_RJT_UNABLE)
            return -EAGAIN; /* might be a temporary condition */
        return -EIO;
    }

    if (hdr->ct_mr_size) {
        dev_warn(&adapter->ccw_device->dev,
             "The name server reported %d words residual data\n",
             hdr->ct_mr_size);
        return -E2BIG;
    }

    /* first entry is the header */
    for (x = 1; x < max_entries && !last; x++) {
        if (x % (ZFCP_FC_GPN_FT_ENT_PAGE + 1))
            acc++;
        else
            acc = sg_virt(++sg);

        last = acc->fp_flags & FC_NS_FID_LAST;
        d_id = ntoh24(acc->fp_fid);

        /* don't attach ports with a well known address */
        if (d_id >= FC_FID_WELL_KNOWN_BASE)
            continue;
        /* skip the adapter's port and known remote ports */
        if (acc->fp_wwpn == fc_host_port_name(adapter->scsi_host))
            continue;

        port = zfcp_port_enqueue(adapter, acc->fp_wwpn,
                     ZFCP_STATUS_COMMON_NOESC, d_id);
        if (!IS_ERR(port))
            zfcp_erp_port_reopen(port, 0, "fcegpf1");
        else if (PTR_ERR(port) != -EEXIST)
            ret = PTR_ERR(port);
    }

    zfcp_erp_wait(adapter);
    write_lock_irqsave(&adapter->port_list_lock, flags);
    list_for_each_entry_safe(port, tmp, &adapter->port_list, list)
        zfcp_fc_validate_port(port, &remove_lh);
    write_unlock_irqrestore(&adapter->port_list_lock, flags);

    list_for_each_entry_safe(port, tmp, &remove_lh, list) {
        zfcp_erp_port_shutdown(port, 0, "fcegpf2");
        zfcp_device_unregister(&port->dev, &zfcp_sysfs_port_attrs);
    }

    return ret;
}

void zfcp_fc_scan_ports(struct work_struct *work)
{
    struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
                            scan_work);
    int ret, i;
    struct zfcp_fc_req *fc_req;
    int chain, max_entries, buf_num, max_bytes;

    chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
    buf_num = chain ? ZFCP_FC_GPN_FT_NUM_BUFS : 1;
    max_entries = chain ? ZFCP_FC_GPN_FT_MAX_ENT : ZFCP_FC_GPN_FT_ENT_PAGE;
    max_bytes = chain ? ZFCP_FC_GPN_FT_MAX_SIZE : ZFCP_FC_CT_SIZE_PAGE;

    if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
        fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
        return;

    if (zfcp_fc_wka_port_get(&adapter->gs->ds))
        return;

    fc_req = zfcp_alloc_sg_env(buf_num);
    if (!fc_req)
        goto out;

    for (i = 0; i < 3; i++) {
        ret = zfcp_fc_send_gpn_ft(fc_req, adapter, max_bytes);
        if (!ret) {
            ret = zfcp_fc_eval_gpn_ft(fc_req, adapter, max_entries);
            if (ret == -EAGAIN)
                ssleep(1);
            else
                break;
        }
    }
    zfcp_sg_free_table(&fc_req->sg_rsp, buf_num);
    kmem_cache_free(zfcp_fc_req_cache, fc_req);
out:
    zfcp_fc_wka_port_put(&adapter->gs->ds);
}

static int zfcp_fc_gspn(struct zfcp_adapter *adapter,
            struct zfcp_fc_req *fc_req)
{
    DECLARE_COMPLETION_ONSTACK(completion);
    char devno[] = "DEVNO:";
    struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
    struct zfcp_fc_gspn_req *gspn_req = &fc_req->u.gspn.req;
    struct zfcp_fc_gspn_rsp *gspn_rsp = &fc_req->u.gspn.rsp;
    int ret;

    zfcp_fc_ct_ns_init(&gspn_req->ct_hdr, FC_NS_GSPN_ID,
               FC_SYMBOLIC_NAME_SIZE);
    hton24(gspn_req->gspn.fp_fid, fc_host_port_id(adapter->scsi_host));

    sg_init_one(&fc_req->sg_req, gspn_req, sizeof(*gspn_req));
    sg_init_one(&fc_req->sg_rsp, gspn_rsp, sizeof(*gspn_rsp));

    ct_els->handler = zfcp_fc_complete;
    ct_els->handler_data = &completion;
    ct_els->req = &fc_req->sg_req;
    ct_els->resp = &fc_req->sg_rsp;

    ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
                   ZFCP_FC_CTELS_TMO);
    if (ret)
        return ret;

    wait_for_completion(&completion);
    if (ct_els->status)
        return ct_els->status;

    if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_NPIV &&
        !(strstr(gspn_rsp->gspn.fp_name, devno)))
        snprintf(fc_host_symbolic_name(adapter->scsi_host),
             FC_SYMBOLIC_NAME_SIZE, "%s%s %s NAME: %s",
             gspn_rsp->gspn.fp_name, devno,
             dev_name(&adapter->ccw_device->dev),
             init_utsname()->nodename);
    else
        strlcpy(fc_host_symbolic_name(adapter->scsi_host),
            gspn_rsp->gspn.fp_name, FC_SYMBOLIC_NAME_SIZE);

    return 0;
}

static void zfcp_fc_rspn(struct zfcp_adapter *adapter,
             struct zfcp_fc_req *fc_req)
{
    DECLARE_COMPLETION_ONSTACK(completion);
    struct Scsi_Host *shost = adapter->scsi_host;
    struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
    struct zfcp_fc_rspn_req *rspn_req = &fc_req->u.rspn.req;
    struct fc_ct_hdr *rspn_rsp = &fc_req->u.rspn.rsp;
    int ret, len;

    zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID,
               FC_SYMBOLIC_NAME_SIZE);
    hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost));
    len = strlcpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost),
              FC_SYMBOLIC_NAME_SIZE);
    rspn_req->rspn.fr_name_len = len;

    sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req));
    sg_init_one(&fc_req->sg_rsp, rspn_rsp, sizeof(*rspn_rsp));

    ct_els->handler = zfcp_fc_complete;
    ct_els->handler_data = &completion;
    ct_els->req = &fc_req->sg_req;
    ct_els->resp = &fc_req->sg_rsp;

    ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
                   ZFCP_FC_CTELS_TMO);
    if (!ret)
        wait_for_completion(&completion);
}

void zfcp_fc_sym_name_update(struct work_struct *work)
{
    struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
                            ns_up_work);
    int ret;
    struct zfcp_fc_req *fc_req;

    if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
        fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
        return;

    fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
    if (!fc_req)
        return;

    ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
    if (ret)
        goto out_free;

    ret = zfcp_fc_gspn(adapter, fc_req);
    if (ret || fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
        goto out_ds_put;

    memset(fc_req, 0, sizeof(*fc_req));
    zfcp_fc_rspn(adapter, fc_req);

out_ds_put:
    zfcp_fc_wka_port_put(&adapter->gs->ds);
out_free:
    kmem_cache_free(zfcp_fc_req_cache, fc_req);
}

static void zfcp_fc_ct_els_job_handler(void *data)
{
    struct fc_bsg_job *job = data;
    struct zfcp_fsf_ct_els *zfcp_ct_els = job->dd_data;
    struct fc_bsg_reply *jr = job->reply;

    jr->reply_payload_rcv_len = job->reply_payload.payload_len;
    jr->reply_data.ctels_reply.status = FC_CTELS_STATUS_OK;
    jr->result = zfcp_ct_els->status ? -EIO : 0;
    job->job_done(job);
}

static struct zfcp_fc_wka_port *zfcp_fc_job_wka_port(struct fc_bsg_job *job)
{
    u32 preamble_word1;
    u8 gs_type;
    struct zfcp_adapter *adapter;

    preamble_word1 = job->request->rqst_data.r_ct.preamble_word1;
    gs_type = (preamble_word1 & 0xff000000) >> 24;

    adapter = (struct zfcp_adapter *) job->shost->hostdata[0];

    switch (gs_type) {
    case FC_FST_ALIAS:
        return &adapter->gs->as;
    case FC_FST_MGMT:
        return &adapter->gs->ms;
    case FC_FST_TIME:
        return &adapter->gs->ts;
        break;
    case FC_FST_DIR:
        return &adapter->gs->ds;
        break;
    default:
        return NULL;
    }
}

static void zfcp_fc_ct_job_handler(void *data)
{
    struct fc_bsg_job *job = data;
    struct zfcp_fc_wka_port *wka_port;

    wka_port = zfcp_fc_job_wka_port(job);
    zfcp_fc_wka_port_put(wka_port);

    zfcp_fc_ct_els_job_handler(data);
}

static int zfcp_fc_exec_els_job(struct fc_bsg_job *job,
                struct zfcp_adapter *adapter)
{
    struct zfcp_fsf_ct_els *els = job->dd_data;
    struct fc_rport *rport = job->rport;
    struct zfcp_port *port;
    u32 d_id;

    if (rport) {
        port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
        if (!port)
            return -EINVAL;

        d_id = port->d_id;
        put_device(&port->dev);
    } else
        d_id = ntoh24(job->request->rqst_data.h_els.port_id);

    els->handler = zfcp_fc_ct_els_job_handler;
    return zfcp_fsf_send_els(adapter, d_id, els, job->req->timeout / HZ);
}

static int zfcp_fc_exec_ct_job(struct fc_bsg_job *job,
                   struct zfcp_adapter *adapter)
{
    int ret;
    struct zfcp_fsf_ct_els *ct = job->dd_data;
    struct zfcp_fc_wka_port *wka_port;

    wka_port = zfcp_fc_job_wka_port(job);
    if (!wka_port)
        return -EINVAL;

    ret = zfcp_fc_wka_port_get(wka_port);
    if (ret)
        return ret;

    ct->handler = zfcp_fc_ct_job_handler;
    ret = zfcp_fsf_send_ct(wka_port, ct, NULL, job->req->timeout / HZ);
    if (ret)
        zfcp_fc_wka_port_put(wka_port);

    return ret;
}

int zfcp_fc_exec_bsg_job(struct fc_bsg_job *job)
{
    struct Scsi_Host *shost;
    struct zfcp_adapter *adapter;
    struct zfcp_fsf_ct_els *ct_els = job->dd_data;

    shost = job->rport ? rport_to_shost(job->rport) : job->shost;
    adapter = (struct zfcp_adapter *)shost->hostdata[0];

    if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN))
        return -EINVAL;

    ct_els->req = job->request_payload.sg_list;
    ct_els->resp = job->reply_payload.sg_list;
    ct_els->handler_data = job;

    switch (job->request->msgcode) {
    case FC_BSG_RPT_ELS:
    case FC_BSG_HST_ELS_NOLOGIN:
        return zfcp_fc_exec_els_job(job, adapter);
    case FC_BSG_RPT_CT:
    case FC_BSG_HST_CT:
        return zfcp_fc_exec_ct_job(job, adapter);
    default:
        return -EINVAL;
    }
}

int zfcp_fc_timeout_bsg_job(struct fc_bsg_job *job)
{
    /* hardware tracks timeout, reset bsg timeout to not interfere */
    return -EAGAIN;
}

int zfcp_fc_gs_setup(struct zfcp_adapter *adapter)
{
    struct zfcp_fc_wka_ports *wka_ports;

    wka_ports = kzalloc(sizeof(struct zfcp_fc_wka_ports), GFP_KERNEL);
    if (!wka_ports)
        return -ENOMEM;

    adapter->gs = wka_ports;
    zfcp_fc_wka_port_init(&wka_ports->ms, FC_FID_MGMT_SERV, adapter);
    zfcp_fc_wka_port_init(&wka_ports->ts, FC_FID_TIME_SERV, adapter);
    zfcp_fc_wka_port_init(&wka_ports->ds, FC_FID_DIR_SERV, adapter);
    zfcp_fc_wka_port_init(&wka_ports->as, FC_FID_ALIASES, adapter);

    return 0;
}

void zfcp_fc_gs_destroy(struct zfcp_adapter *adapter)
{
    kfree(adapter->gs);
    adapter->gs = NULL;
}