zfcp_ccw.c

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/*
 * zfcp device driver
 *
 * Registration and callback for the s390 common I/O layer.
 *
 * Copyright IBM Corp. 2002, 2010
 */

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

#include <linux/module.h>
#include "zfcp_ext.h"
#include "zfcp_reqlist.h"

#define ZFCP_MODEL_PRIV 0x4

static DEFINE_SPINLOCK(zfcp_ccw_adapter_ref_lock);

struct zfcp_adapter *zfcp_ccw_adapter_by_cdev(struct ccw_device *cdev)
{
    struct zfcp_adapter *adapter;
    unsigned long flags;

    spin_lock_irqsave(&zfcp_ccw_adapter_ref_lock, flags);
    adapter = dev_get_drvdata(&cdev->dev);
    if (adapter)
        kref_get(&adapter->ref);
    spin_unlock_irqrestore(&zfcp_ccw_adapter_ref_lock, flags);
    return adapter;
}

void zfcp_ccw_adapter_put(struct zfcp_adapter *adapter)
{
    unsigned long flags;

    spin_lock_irqsave(&zfcp_ccw_adapter_ref_lock, flags);
    kref_put(&adapter->ref, zfcp_adapter_release);
    spin_unlock_irqrestore(&zfcp_ccw_adapter_ref_lock, flags);
}

static int zfcp_ccw_activate(struct ccw_device *cdev, int clear, char *tag)
{
    struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);

    if (!adapter)
        return 0;

    zfcp_erp_clear_adapter_status(adapter, clear);
    zfcp_erp_set_adapter_status(adapter, ZFCP_STATUS_COMMON_RUNNING);
    zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED,
                tag);
    zfcp_erp_wait(adapter);
    flush_work(&adapter->scan_work); /* ok to call even if nothing queued */

    zfcp_ccw_adapter_put(adapter);

    return 0;
}

static struct ccw_device_id zfcp_ccw_device_id[] = {
    { CCW_DEVICE_DEVTYPE(0x1731, 0x3, 0x1732, 0x3) },
    { CCW_DEVICE_DEVTYPE(0x1731, 0x3, 0x1732, ZFCP_MODEL_PRIV) },
    {},
};
MODULE_DEVICE_TABLE(ccw, zfcp_ccw_device_id);

int zfcp_ccw_priv_sch(struct zfcp_adapter *adapter)
{
    return adapter->ccw_device->id.dev_model == ZFCP_MODEL_PRIV;
}

static int zfcp_ccw_probe(struct ccw_device *cdev)
{
    return 0;
}

static void zfcp_ccw_remove(struct ccw_device *cdev)
{
    struct zfcp_adapter *adapter;
    struct zfcp_port *port, *p;
    struct zfcp_unit *unit, *u;
    LIST_HEAD(unit_remove_lh);
    LIST_HEAD(port_remove_lh);

    ccw_device_set_offline(cdev);

    adapter = zfcp_ccw_adapter_by_cdev(cdev);
    if (!adapter)
        return;

    write_lock_irq(&adapter->port_list_lock);
    list_for_each_entry_safe(port, p, &adapter->port_list, list) {
        write_lock(&port->unit_list_lock);
        list_for_each_entry_safe(unit, u, &port->unit_list, list)
            list_move(&unit->list, &unit_remove_lh);
        write_unlock(&port->unit_list_lock);
        list_move(&port->list, &port_remove_lh);
    }
    write_unlock_irq(&adapter->port_list_lock);
    zfcp_ccw_adapter_put(adapter); /* put from zfcp_ccw_adapter_by_cdev */

    list_for_each_entry_safe(unit, u, &unit_remove_lh, list)
        zfcp_device_unregister(&unit->dev, &zfcp_sysfs_unit_attrs);

    list_for_each_entry_safe(port, p, &port_remove_lh, list)
        zfcp_device_unregister(&port->dev, &zfcp_sysfs_port_attrs);

    zfcp_adapter_unregister(adapter);
}

static int zfcp_ccw_set_online(struct ccw_device *cdev)
{
    struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);

    if (!adapter) {
        adapter = zfcp_adapter_enqueue(cdev);

        if (IS_ERR(adapter)) {
            dev_err(&cdev->dev,
                "Setting up data structures for the "
                "FCP adapter failed\n");
            return PTR_ERR(adapter);
        }
        kref_get(&adapter->ref);
    }

    /* initialize request counter */
    BUG_ON(!zfcp_reqlist_isempty(adapter->req_list));
    adapter->req_no = 0;

    zfcp_ccw_activate(cdev, 0, "ccsonl1");
    /* scan for remote ports
       either at the end of any successful adapter recovery
       or only after the adapter recovery for setting a device online */
    zfcp_fc_inverse_conditional_port_scan(adapter);
    flush_work(&adapter->scan_work); /* ok to call even if nothing queued */
    zfcp_ccw_adapter_put(adapter);
    return 0;
}

static int zfcp_ccw_offline_sync(struct ccw_device *cdev, int set, char *tag)
{
    struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);

    if (!adapter)
        return 0;

    zfcp_erp_set_adapter_status(adapter, set);
    zfcp_erp_adapter_shutdown(adapter, 0, tag);
    zfcp_erp_wait(adapter);

    zfcp_ccw_adapter_put(adapter);
    return 0;
}

static int zfcp_ccw_set_offline(struct ccw_device *cdev)
{
    return zfcp_ccw_offline_sync(cdev, 0, "ccsoff1");
}

static int zfcp_ccw_notify(struct ccw_device *cdev, int event)
{
    struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);

    if (!adapter)
        return 1;

    switch (event) {
    case CIO_GONE:
        if (atomic_read(&adapter->status) &
            ZFCP_STATUS_ADAPTER_SUSPENDED) { /* notification ignore */
            zfcp_dbf_hba_basic("ccnigo1", adapter);
            break;
        }
        dev_warn(&cdev->dev, "The FCP device has been detached\n");
        zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti1");
        break;
    case CIO_NO_PATH:
        dev_warn(&cdev->dev,
             "The CHPID for the FCP device is offline\n");
        zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti2");
        break;
    case CIO_OPER:
        if (atomic_read(&adapter->status) &
            ZFCP_STATUS_ADAPTER_SUSPENDED) { /* notification ignore */
            zfcp_dbf_hba_basic("ccniop1", adapter);
            break;
        }
        dev_info(&cdev->dev, "The FCP device is operational again\n");
        zfcp_erp_set_adapter_status(adapter,
                        ZFCP_STATUS_COMMON_RUNNING);
        zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED,
                    "ccnoti4");
        break;
    case CIO_BOXED:
        dev_warn(&cdev->dev, "The FCP device did not respond within "
                     "the specified time\n");
        zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti5");
        break;
    }

    zfcp_ccw_adapter_put(adapter);
    return 1;
}

static void zfcp_ccw_shutdown(struct ccw_device *cdev)
{
    struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);

    if (!adapter)
        return;

    zfcp_erp_adapter_shutdown(adapter, 0, "ccshut1");
    zfcp_erp_wait(adapter);
    zfcp_erp_thread_kill(adapter);

    zfcp_ccw_adapter_put(adapter);
}

static int zfcp_ccw_suspend(struct ccw_device *cdev)
{
    zfcp_ccw_offline_sync(cdev, ZFCP_STATUS_ADAPTER_SUSPENDED, "ccsusp1");
    return 0;
}

static int zfcp_ccw_thaw(struct ccw_device *cdev)
{
    /* trace records for thaw and final shutdown during suspend
       can only be found in system dump until the end of suspend
       but not after resume because it's based on the memory image
       right after the very first suspend (freeze) callback */
    zfcp_ccw_activate(cdev, 0, "ccthaw1");
    return 0;
}

static int zfcp_ccw_resume(struct ccw_device *cdev)
{
    zfcp_ccw_activate(cdev, ZFCP_STATUS_ADAPTER_SUSPENDED, "ccresu1");
    return 0;
}

struct ccw_driver zfcp_ccw_driver = {
    .driver = {
        .owner  = THIS_MODULE,
        .name   = "zfcp",
    },
    .ids         = zfcp_ccw_device_id,
    .probe       = zfcp_ccw_probe,
    .remove      = zfcp_ccw_remove,
    .set_online  = zfcp_ccw_set_online,
    .set_offline = zfcp_ccw_set_offline,
    .notify      = zfcp_ccw_notify,
    .shutdown    = zfcp_ccw_shutdown,
    .freeze      = zfcp_ccw_suspend,
    .thaw        = zfcp_ccw_thaw,
    .restore     = zfcp_ccw_resume,
};