Quelle  zfcp_aux.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0
/*
 * zfcp device driver
 *
 * Module interface and handling of zfcp data structures.
 *
 * Copyright IBM Corp. 2002, 2020
 */

/*
 * Driver authors:
 *            Martin Peschke (originator of the driver)
 *            Raimund Schroeder
 *            Aron Zeh
 *            Wolfgang Taphorn
 *            Stefan Bader
 *            Heiko Carstens (kernel 2.6 port of the driver)
 *            Andreas Herrmann
 *            Maxim Shchetynin
 *            Volker Sameske
 *            Ralph Wuerthner
 *            Michael Loehr
 *            Swen Schillig
 *            Christof Schmitt
 *            Martin Petermann
 *            Sven Schuetz
 *            Steffen Maier
 *       Benjamin Block
 */

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

#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/module.h>
#include "zfcp_ext.h"
#include "zfcp_fc.h"
#include "zfcp_reqlist.h"
#include "zfcp_diag.h"

#define ZFCP_BUS_ID_SIZE 20

MODULE_AUTHOR("IBM Corporation");
MODULE_DESCRIPTION("FCP HBA driver");
MODULE_LICENSE("GPL");

static char *init_device;
module_param_named(device, init_device, charp, 0400);
MODULE_PARM_DESC(device, "specify initial device");

static struct kmem_cache * __init zfcp_cache_hw_align(const char *name,
            unsigned long size)
{
 return kmem_cache_create(name, size, roundup_pow_of_two(size), 0, NULL);
}

static void __init zfcp_init_device_configure(char *busid, u64 wwpn, u64 lun)
{
 struct ccw_device *cdev;
 struct zfcp_adapter *adapter;
 struct zfcp_port *port;

 cdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
 if (!cdev)
  return;

 if (ccw_device_set_online(cdev))
  goto out_ccw_device;

 adapter = zfcp_ccw_adapter_by_cdev(cdev);
 if (!adapter)
  goto out_ccw_device;

 port = zfcp_get_port_by_wwpn(adapter, wwpn);
 if (!port)
  goto out_port;
 flush_work(&port->rport_work);

 zfcp_unit_add(port, lun);
 put_device(&port->dev);

out_port:
 zfcp_ccw_adapter_put(adapter);
out_ccw_device:
 put_device(&cdev->dev);
 return;
}

static void __init zfcp_init_device_setup(char *devstr)
{
 char *token;
 char *str, *str_saved;
 char busid[ZFCP_BUS_ID_SIZE];
 u64 wwpn, lun;

 /* duplicate devstr and keep the original for sysfs presentation*/
 str_saved = kstrdup(devstr, GFP_KERNEL);
 str = str_saved;
 if (!str)
  return;

 token = strsep(&str, ",");
 if (!token || strlen(token) >= ZFCP_BUS_ID_SIZE)
  goto err_out;
 strscpy(busid, token, ZFCP_BUS_ID_SIZE);

 token = strsep(&str, ",");
 if (!token || kstrtoull(token, 0, (unsigned long long *) &wwpn))
  goto err_out;

 token = strsep(&str, ",");
 if (!token || kstrtoull(token, 0, (unsigned long long *) &lun))
  goto err_out;

 kfree(str_saved);
 zfcp_init_device_configure(busid, wwpn, lun);
 return;

err_out:
 kfree(str_saved);
 pr_err("%s is not a valid SCSI device\n", devstr);
}

static int __init zfcp_module_init(void)
{
 int retval = -ENOMEM;

 if (zfcp_experimental_dix)
  pr_warn("DIX is enabled. It is experimental and might cause problems\n");

 zfcp_fsf_qtcb_cache = zfcp_cache_hw_align("zfcp_fsf_qtcb",
        sizeof(struct fsf_qtcb));
 if (!zfcp_fsf_qtcb_cache)
  goto out_qtcb_cache;

 zfcp_fc_req_cache = zfcp_cache_hw_align("zfcp_fc_req",
      sizeof(struct zfcp_fc_req));
 if (!zfcp_fc_req_cache)
  goto out_fc_cache;

 zfcp_scsi_transport_template =
  fc_attach_transport(&zfcp_transport_functions);
 if (!zfcp_scsi_transport_template)
  goto out_transport;
 scsi_transport_reserve_device(zfcp_scsi_transport_template,
          sizeof(struct zfcp_scsi_dev));

 retval = ccw_driver_register(&zfcp_ccw_driver);
 if (retval) {
  pr_err("The zfcp device driver could not register with "
         "the common I/O layer\n");
  goto out_ccw_register;
 }

 if (init_device)
  zfcp_init_device_setup(init_device);
 return 0;

out_ccw_register:
 fc_release_transport(zfcp_scsi_transport_template);
out_transport:
 kmem_cache_destroy(zfcp_fc_req_cache);
out_fc_cache:
 kmem_cache_destroy(zfcp_fsf_qtcb_cache);
out_qtcb_cache:
 return retval;
}

module_init(zfcp_module_init);

static void __exit zfcp_module_exit(void)
{
 ccw_driver_unregister(&zfcp_ccw_driver);
 fc_release_transport(zfcp_scsi_transport_template);
 kmem_cache_destroy(zfcp_fc_req_cache);
 kmem_cache_destroy(zfcp_fsf_qtcb_cache);
}

module_exit(zfcp_module_exit);

/**
 * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
 * @adapter: pointer to adapter to search for port
 * @wwpn: wwpn to search for
 *
 * Returns: pointer to zfcp_port or NULL
 */
struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
     u64 wwpn)
{
 unsigned long flags;
 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) {
   if (!get_device(&port->dev))
    port = NULL;
   read_unlock_irqrestore(&adapter->port_list_lock, flags);
   return port;
  }
 read_unlock_irqrestore(&adapter->port_list_lock, flags);
 return NULL;
}

static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
{
 adapter->pool.erp_req =
  mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
 if (!adapter->pool.erp_req)
  return -ENOMEM;

 adapter->pool.gid_pn_req =
  mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
 if (!adapter->pool.gid_pn_req)
  return -ENOMEM;

 adapter->pool.scsi_req =
  mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
 if (!adapter->pool.scsi_req)
  return -ENOMEM;

 adapter->pool.scsi_abort =
  mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
 if (!adapter->pool.scsi_abort)
  return -ENOMEM;

 adapter->pool.status_read_req =
  mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
         sizeof(struct zfcp_fsf_req));
 if (!adapter->pool.status_read_req)
  return -ENOMEM;

 adapter->pool.qtcb_pool =
  mempool_create_slab_pool(4, zfcp_fsf_qtcb_cache);
 if (!adapter->pool.qtcb_pool)
  return -ENOMEM;

 BUILD_BUG_ON(sizeof(struct fsf_status_read_buffer) > PAGE_SIZE);
 adapter->pool.sr_data =
  mempool_create_page_pool(FSF_STATUS_READS_RECOM, 0);
 if (!adapter->pool.sr_data)
  return -ENOMEM;

 adapter->pool.gid_pn =
  mempool_create_slab_pool(1, zfcp_fc_req_cache);
 if (!adapter->pool.gid_pn)
  return -ENOMEM;

 return 0;
}

static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
{
 mempool_destroy(adapter->pool.erp_req);
 mempool_destroy(adapter->pool.scsi_req);
 mempool_destroy(adapter->pool.scsi_abort);
 mempool_destroy(adapter->pool.qtcb_pool);
 mempool_destroy(adapter->pool.status_read_req);
 mempool_destroy(adapter->pool.sr_data);
 mempool_destroy(adapter->pool.gid_pn);
}

/**
 * zfcp_status_read_refill - refill the long running status_read_requests
 * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
 *
 * Return:
 * * 0 on success meaning at least one status read is pending
 * * 1 if posting failed and not a single status read buffer is pending,
 *     also triggers adapter reopen recovery
 */
int zfcp_status_read_refill(struct zfcp_adapter *adapter)
{
 while (atomic_add_unless(&adapter->stat_miss, -1, 0))
  if (zfcp_fsf_status_read(adapter->qdio)) {
   atomic_inc(&adapter->stat_miss); /* undo add -1 */
   if (atomic_read(&adapter->stat_miss) >=
       adapter->stat_read_buf_num) {
    zfcp_erp_adapter_reopen(adapter, 0, "axsref1");
    return 1;
   }
   break;
  }
 return 0;
}

static void _zfcp_status_read_scheduler(struct work_struct *work)
{
 zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
          stat_work));
}

static void zfcp_version_change_lost_work(struct work_struct *work)
{
 struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
          version_change_lost_work);

 zfcp_fsf_exchange_config_data_sync(adapter->qdio, NULL);
}

static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
{
 struct zfcp_adapter *adapter =
  container_of(sl, struct zfcp_adapter, service_level);

 seq_printf(m, "zfcp: %s microcode level %x\n",
     dev_name(&adapter->ccw_device->dev),
     adapter->fsf_lic_version);
}

static int zfcp_setup_adapter_work_queue(struct zfcp_adapter *adapter)
{
 adapter->work_queue =
  alloc_ordered_workqueue("zfcp_q_%s", WQ_MEM_RECLAIM,
     dev_name(&adapter->ccw_device->dev));
 if (!adapter->work_queue)
  return -ENOMEM;

 return 0;
}

static void zfcp_destroy_adapter_work_queue(struct zfcp_adapter *adapter)
{
 if (adapter->work_queue)
  destroy_workqueue(adapter->work_queue);
 adapter->work_queue = NULL;

}

/**
 * zfcp_adapter_enqueue - enqueue a new adapter to the list
 * @ccw_device: pointer to the struct cc_device
 *
 * Returns: struct zfcp_adapter*
 * Enqueues an adapter at the end of the adapter list in the driver data.
 * All adapter internal structures are set up.
 * Proc-fs entries are also created.
 */
struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
{
 struct zfcp_adapter *adapter;

 if (!get_device(&ccw_device->dev))
  return ERR_PTR(-ENODEV);

 adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
 if (!adapter) {
  put_device(&ccw_device->dev);
  return ERR_PTR(-ENOMEM);
 }

 kref_init(&adapter->ref);

 ccw_device->handler = NULL;
 adapter->ccw_device = ccw_device;

 INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
 INIT_DELAYED_WORK(&adapter->scan_work, zfcp_fc_scan_ports);
 INIT_WORK(&adapter->ns_up_work, zfcp_fc_sym_name_update);
 INIT_WORK(&adapter->version_change_lost_work,
    zfcp_version_change_lost_work);

 adapter->next_port_scan = jiffies;

 adapter->erp_action.adapter = adapter;

 if (zfcp_diag_adapter_setup(adapter))
  goto failed;

 if (zfcp_qdio_setup(adapter))
  goto failed;

 if (zfcp_allocate_low_mem_buffers(adapter))
  goto failed;

 adapter->req_list = zfcp_reqlist_alloc();
 if (!adapter->req_list)
  goto failed;

 if (zfcp_dbf_adapter_register(adapter))
  goto failed;

 if (zfcp_setup_adapter_work_queue(adapter))
  goto failed;

 if (zfcp_fc_gs_setup(adapter))
  goto failed;

 rwlock_init(&adapter->port_list_lock);
 INIT_LIST_HEAD(&adapter->port_list);

 INIT_LIST_HEAD(&adapter->events.list);
 INIT_WORK(&adapter->events.work, zfcp_fc_post_event);
 spin_lock_init(&adapter->events.list_lock);

 init_waitqueue_head(&adapter->erp_ready_wq);
 init_waitqueue_head(&adapter->erp_done_wqh);

 INIT_LIST_HEAD(&adapter->erp_ready_head);
 INIT_LIST_HEAD(&adapter->erp_running_head);

 rwlock_init(&adapter->erp_lock);
 rwlock_init(&adapter->abort_lock);

 if (zfcp_erp_thread_setup(adapter))
  goto failed;

 adapter->service_level.seq_print = zfcp_print_sl;

 dev_set_drvdata(&ccw_device->dev, adapter);

 if (device_add_groups(&ccw_device->dev, zfcp_sysfs_adapter_attr_groups))
  goto err_sysfs;

 /* report size limit per scatter-gather segment */
 adapter->ccw_device->dev.dma_parms = &adapter->dma_parms;

 adapter->stat_read_buf_num = FSF_STATUS_READS_RECOM;

 return adapter;

err_sysfs:
failed:
 /* TODO: make this more fine-granular */
 cancel_delayed_work_sync(&adapter->scan_work);
 cancel_work_sync(&adapter->stat_work);
 cancel_work_sync(&adapter->ns_up_work);
 cancel_work_sync(&adapter->version_change_lost_work);
 zfcp_destroy_adapter_work_queue(adapter);

 zfcp_fc_wka_ports_force_offline(adapter->gs);
 zfcp_scsi_adapter_unregister(adapter);

 zfcp_erp_thread_kill(adapter);
 zfcp_dbf_adapter_unregister(adapter);
 zfcp_qdio_destroy(adapter->qdio);

 zfcp_ccw_adapter_put(adapter); /* final put to release */
 return ERR_PTR(-ENOMEM);
}

void zfcp_adapter_unregister(struct zfcp_adapter *adapter)
{
 struct ccw_device *cdev = adapter->ccw_device;

 cancel_delayed_work_sync(&adapter->scan_work);
 cancel_work_sync(&adapter->stat_work);
 cancel_work_sync(&adapter->ns_up_work);
 cancel_work_sync(&adapter->version_change_lost_work);
 zfcp_destroy_adapter_work_queue(adapter);

 zfcp_fc_wka_ports_force_offline(adapter->gs);
 zfcp_scsi_adapter_unregister(adapter);
 device_remove_groups(&cdev->dev, zfcp_sysfs_adapter_attr_groups);

 zfcp_erp_thread_kill(adapter);
 zfcp_dbf_adapter_unregister(adapter);
 zfcp_qdio_destroy(adapter->qdio);

 zfcp_ccw_adapter_put(adapter); /* final put to release */
}

/**
 * zfcp_adapter_release - remove the adapter from the resource list
 * @ref: pointer to struct kref
 * locks: adapter list write lock is assumed to be held by caller
 */
void zfcp_adapter_release(struct kref *ref)
{
 struct zfcp_adapter *adapter = container_of(ref, struct zfcp_adapter,
          ref);
 struct ccw_device *cdev = adapter->ccw_device;

 dev_set_drvdata(&adapter->ccw_device->dev, NULL);
 zfcp_fc_gs_destroy(adapter);
 zfcp_free_low_mem_buffers(adapter);
 zfcp_diag_adapter_free(adapter);
 kfree(adapter->req_list);
 kfree(adapter->fc_stats);
 kfree(adapter->stats_reset_data);
 kfree(adapter);
 put_device(&cdev->dev);
}

static void zfcp_port_release(struct device *dev)
{
 struct zfcp_port *port = container_of(dev, struct zfcp_port, dev);

 zfcp_ccw_adapter_put(port->adapter);
 kfree(port);
}

/**
 * zfcp_port_enqueue - enqueue port to port list of adapter
 * @adapter: adapter where remote port is added
 * @wwpn: WWPN of the remote port to be enqueued
 * @status: initial status for the port
 * @d_id: destination id of the remote port to be enqueued
 * Returns: pointer to enqueued port on success, ERR_PTR on error
 *
 * All port internal structures are set up and the sysfs entry is generated.
 * d_id is used to enqueue ports with a well known address like the Directory
 * Service for nameserver lookup.
 */
struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
         u32 status, u32 d_id)
{
 struct zfcp_port *port;
 int retval = -ENOMEM;

 kref_get(&adapter->ref);

 port = zfcp_get_port_by_wwpn(adapter, wwpn);
 if (port) {
  put_device(&port->dev);
  retval = -EEXIST;
  goto err_put;
 }

 port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
 if (!port)
  goto err_put;

 rwlock_init(&port->unit_list_lock);
 INIT_LIST_HEAD(&port->unit_list);
 atomic_set(&port->units, 0);

 INIT_WORK(&port->gid_pn_work, zfcp_fc_port_did_lookup);
 INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
 INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);

 port->adapter = adapter;
 port->d_id = d_id;
 port->wwpn = wwpn;
 port->rport_task = RPORT_NONE;
 port->dev.parent = &adapter->ccw_device->dev;
 port->dev.groups = zfcp_port_attr_groups;
 port->dev.release = zfcp_port_release;

 port->erp_action.adapter = adapter;
 port->erp_action.port = port;

 if (dev_set_name(&port->dev, "0x%016llx", (unsigned long long)wwpn)) {
  kfree(port);
  goto err_put;
 }
 retval = -EINVAL;

 if (device_register(&port->dev)) {
  put_device(&port->dev);
  goto err_out;
 }

 write_lock_irq(&adapter->port_list_lock);
 list_add_tail(&port->list, &adapter->port_list);
 write_unlock_irq(&adapter->port_list_lock);

 atomic_or(status | ZFCP_STATUS_COMMON_RUNNING, &port->status);

 return port;

err_put:
 zfcp_ccw_adapter_put(adapter);
err_out:
 return ERR_PTR(retval);
}