[SCSI] zfcp: Rename sysfs_device attribute to dev in zfcp_unit and zfcp_port
[linux-2.6.git] / drivers / s390 / scsi / zfcp_aux.c
1 /*
2  * zfcp device driver
3  *
4  * Module interface and handling of zfcp data structures.
5  *
6  * Copyright IBM Corporation 2002, 2010
7  */
8
9 /*
10  * Driver authors:
11  *            Martin Peschke (originator of the driver)
12  *            Raimund Schroeder
13  *            Aron Zeh
14  *            Wolfgang Taphorn
15  *            Stefan Bader
16  *            Heiko Carstens (kernel 2.6 port of the driver)
17  *            Andreas Herrmann
18  *            Maxim Shchetynin
19  *            Volker Sameske
20  *            Ralph Wuerthner
21  *            Michael Loehr
22  *            Swen Schillig
23  *            Christof Schmitt
24  *            Martin Petermann
25  *            Sven Schuetz
26  */
27
28 #define KMSG_COMPONENT "zfcp"
29 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
30
31 #include <linux/miscdevice.h>
32 #include <linux/seq_file.h>
33 #include "zfcp_ext.h"
34 #include "zfcp_fc.h"
35 #include "zfcp_reqlist.h"
36
37 #define ZFCP_BUS_ID_SIZE        20
38
39 MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
40 MODULE_DESCRIPTION("FCP HBA driver");
41 MODULE_LICENSE("GPL");
42
43 static char *init_device;
44 module_param_named(device, init_device, charp, 0400);
45 MODULE_PARM_DESC(device, "specify initial device");
46
47 static struct kmem_cache *zfcp_cache_hw_align(const char *name,
48                                               unsigned long size)
49 {
50         return kmem_cache_create(name, size, roundup_pow_of_two(size), 0, NULL);
51 }
52
53 static void __init zfcp_init_device_configure(char *busid, u64 wwpn, u64 lun)
54 {
55         struct ccw_device *cdev;
56         struct zfcp_adapter *adapter;
57         struct zfcp_port *port;
58         struct zfcp_unit *unit;
59
60         cdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
61         if (!cdev)
62                 return;
63
64         if (ccw_device_set_online(cdev))
65                 goto out_ccw_device;
66
67         adapter = zfcp_ccw_adapter_by_cdev(cdev);
68         if (!adapter)
69                 goto out_ccw_device;
70
71         port = zfcp_get_port_by_wwpn(adapter, wwpn);
72         if (!port)
73                 goto out_port;
74
75         unit = zfcp_unit_enqueue(port, lun);
76         if (IS_ERR(unit))
77                 goto out_unit;
78
79         zfcp_erp_unit_reopen(unit, 0, "auidc_1", NULL);
80         zfcp_erp_wait(adapter);
81         flush_work(&unit->scsi_work);
82
83 out_unit:
84         put_device(&port->dev);
85 out_port:
86         zfcp_ccw_adapter_put(adapter);
87 out_ccw_device:
88         put_device(&cdev->dev);
89         return;
90 }
91
92 static void __init zfcp_init_device_setup(char *devstr)
93 {
94         char *token;
95         char *str, *str_saved;
96         char busid[ZFCP_BUS_ID_SIZE];
97         u64 wwpn, lun;
98
99         /* duplicate devstr and keep the original for sysfs presentation*/
100         str_saved = kmalloc(strlen(devstr) + 1, GFP_KERNEL);
101         str = str_saved;
102         if (!str)
103                 return;
104
105         strcpy(str, devstr);
106
107         token = strsep(&str, ",");
108         if (!token || strlen(token) >= ZFCP_BUS_ID_SIZE)
109                 goto err_out;
110         strncpy(busid, token, ZFCP_BUS_ID_SIZE);
111
112         token = strsep(&str, ",");
113         if (!token || strict_strtoull(token, 0, (unsigned long long *) &wwpn))
114                 goto err_out;
115
116         token = strsep(&str, ",");
117         if (!token || strict_strtoull(token, 0, (unsigned long long *) &lun))
118                 goto err_out;
119
120         kfree(str_saved);
121         zfcp_init_device_configure(busid, wwpn, lun);
122         return;
123
124 err_out:
125         kfree(str_saved);
126         pr_err("%s is not a valid SCSI device\n", devstr);
127 }
128
129 static int __init zfcp_module_init(void)
130 {
131         int retval = -ENOMEM;
132
133         zfcp_data.gpn_ft_cache = zfcp_cache_hw_align("zfcp_gpn",
134                                         sizeof(struct zfcp_fc_gpn_ft_req));
135         if (!zfcp_data.gpn_ft_cache)
136                 goto out;
137
138         zfcp_data.qtcb_cache = zfcp_cache_hw_align("zfcp_qtcb",
139                                         sizeof(struct fsf_qtcb));
140         if (!zfcp_data.qtcb_cache)
141                 goto out_qtcb_cache;
142
143         zfcp_data.sr_buffer_cache = zfcp_cache_hw_align("zfcp_sr",
144                                         sizeof(struct fsf_status_read_buffer));
145         if (!zfcp_data.sr_buffer_cache)
146                 goto out_sr_cache;
147
148         zfcp_data.gid_pn_cache = zfcp_cache_hw_align("zfcp_gid",
149                                         sizeof(struct zfcp_fc_gid_pn));
150         if (!zfcp_data.gid_pn_cache)
151                 goto out_gid_cache;
152
153         zfcp_data.adisc_cache = zfcp_cache_hw_align("zfcp_adisc",
154                                         sizeof(struct zfcp_fc_els_adisc));
155         if (!zfcp_data.adisc_cache)
156                 goto out_adisc_cache;
157
158         zfcp_data.scsi_transport_template =
159                 fc_attach_transport(&zfcp_transport_functions);
160         if (!zfcp_data.scsi_transport_template)
161                 goto out_transport;
162
163         retval = misc_register(&zfcp_cfdc_misc);
164         if (retval) {
165                 pr_err("Registering the misc device zfcp_cfdc failed\n");
166                 goto out_misc;
167         }
168
169         retval = ccw_driver_register(&zfcp_ccw_driver);
170         if (retval) {
171                 pr_err("The zfcp device driver could not register with "
172                        "the common I/O layer\n");
173                 goto out_ccw_register;
174         }
175
176         if (init_device)
177                 zfcp_init_device_setup(init_device);
178         return 0;
179
180 out_ccw_register:
181         misc_deregister(&zfcp_cfdc_misc);
182 out_misc:
183         fc_release_transport(zfcp_data.scsi_transport_template);
184 out_transport:
185         kmem_cache_destroy(zfcp_data.adisc_cache);
186 out_adisc_cache:
187         kmem_cache_destroy(zfcp_data.gid_pn_cache);
188 out_gid_cache:
189         kmem_cache_destroy(zfcp_data.sr_buffer_cache);
190 out_sr_cache:
191         kmem_cache_destroy(zfcp_data.qtcb_cache);
192 out_qtcb_cache:
193         kmem_cache_destroy(zfcp_data.gpn_ft_cache);
194 out:
195         return retval;
196 }
197
198 module_init(zfcp_module_init);
199
200 static void __exit zfcp_module_exit(void)
201 {
202         ccw_driver_unregister(&zfcp_ccw_driver);
203         misc_deregister(&zfcp_cfdc_misc);
204         fc_release_transport(zfcp_data.scsi_transport_template);
205         kmem_cache_destroy(zfcp_data.adisc_cache);
206         kmem_cache_destroy(zfcp_data.gid_pn_cache);
207         kmem_cache_destroy(zfcp_data.sr_buffer_cache);
208         kmem_cache_destroy(zfcp_data.qtcb_cache);
209         kmem_cache_destroy(zfcp_data.gpn_ft_cache);
210 }
211
212 module_exit(zfcp_module_exit);
213
214 /**
215  * zfcp_get_unit_by_lun - find unit in unit list of port by FCP LUN
216  * @port: pointer to port to search for unit
217  * @fcp_lun: FCP LUN to search for
218  *
219  * Returns: pointer to zfcp_unit or NULL
220  */
221 struct zfcp_unit *zfcp_get_unit_by_lun(struct zfcp_port *port, u64 fcp_lun)
222 {
223         unsigned long flags;
224         struct zfcp_unit *unit;
225
226         read_lock_irqsave(&port->unit_list_lock, flags);
227         list_for_each_entry(unit, &port->unit_list, list)
228                 if (unit->fcp_lun == fcp_lun) {
229                         if (!get_device(&unit->dev))
230                                 unit = NULL;
231                         read_unlock_irqrestore(&port->unit_list_lock, flags);
232                         return unit;
233                 }
234         read_unlock_irqrestore(&port->unit_list_lock, flags);
235         return NULL;
236 }
237
238 /**
239  * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
240  * @adapter: pointer to adapter to search for port
241  * @wwpn: wwpn to search for
242  *
243  * Returns: pointer to zfcp_port or NULL
244  */
245 struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
246                                         u64 wwpn)
247 {
248         unsigned long flags;
249         struct zfcp_port *port;
250
251         read_lock_irqsave(&adapter->port_list_lock, flags);
252         list_for_each_entry(port, &adapter->port_list, list)
253                 if (port->wwpn == wwpn) {
254                         if (!get_device(&port->dev))
255                                 port = NULL;
256                         read_unlock_irqrestore(&adapter->port_list_lock, flags);
257                         return port;
258                 }
259         read_unlock_irqrestore(&adapter->port_list_lock, flags);
260         return NULL;
261 }
262
263 /**
264  * zfcp_unit_release - dequeue unit
265  * @dev: pointer to device
266  *
267  * waits until all work is done on unit and removes it then from the unit->list
268  * of the associated port.
269  */
270 static void zfcp_unit_release(struct device *dev)
271 {
272         struct zfcp_unit *unit = container_of(dev, struct zfcp_unit, dev);
273
274         put_device(&unit->port->dev);
275         kfree(unit);
276 }
277
278 /**
279  * zfcp_unit_enqueue - enqueue unit to unit list of a port.
280  * @port: pointer to port where unit is added
281  * @fcp_lun: FCP LUN of unit to be enqueued
282  * Returns: pointer to enqueued unit on success, ERR_PTR on error
283  *
284  * Sets up some unit internal structures and creates sysfs entry.
285  */
286 struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
287 {
288         struct zfcp_unit *unit;
289         int retval = -ENOMEM;
290
291         get_device(&port->dev);
292
293         unit = zfcp_get_unit_by_lun(port, fcp_lun);
294         if (unit) {
295                 put_device(&unit->dev);
296                 retval = -EEXIST;
297                 goto err_out;
298         }
299
300         unit = kzalloc(sizeof(struct zfcp_unit), GFP_KERNEL);
301         if (!unit)
302                 goto err_out;
303
304         unit->port = port;
305         unit->fcp_lun = fcp_lun;
306         unit->dev.parent = &port->dev;
307         unit->dev.release = zfcp_unit_release;
308
309         if (dev_set_name(&unit->dev, "0x%016llx",
310                          (unsigned long long) fcp_lun)) {
311                 kfree(unit);
312                 goto err_out;
313         }
314         retval = -EINVAL;
315
316         INIT_WORK(&unit->scsi_work, zfcp_scsi_scan);
317
318         spin_lock_init(&unit->latencies.lock);
319         unit->latencies.write.channel.min = 0xFFFFFFFF;
320         unit->latencies.write.fabric.min = 0xFFFFFFFF;
321         unit->latencies.read.channel.min = 0xFFFFFFFF;
322         unit->latencies.read.fabric.min = 0xFFFFFFFF;
323         unit->latencies.cmd.channel.min = 0xFFFFFFFF;
324         unit->latencies.cmd.fabric.min = 0xFFFFFFFF;
325
326         if (device_register(&unit->dev)) {
327                 put_device(&unit->dev);
328                 goto err_out;
329         }
330
331         if (sysfs_create_group(&unit->dev.kobj, &zfcp_sysfs_unit_attrs))
332                 goto err_out_put;
333
334         write_lock_irq(&port->unit_list_lock);
335         list_add_tail(&unit->list, &port->unit_list);
336         write_unlock_irq(&port->unit_list_lock);
337
338         atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status);
339
340         return unit;
341
342 err_out_put:
343         device_unregister(&unit->dev);
344 err_out:
345         put_device(&port->dev);
346         return ERR_PTR(retval);
347 }
348
349 static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
350 {
351         adapter->pool.erp_req =
352                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
353         if (!adapter->pool.erp_req)
354                 return -ENOMEM;
355
356         adapter->pool.gid_pn_req =
357                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
358         if (!adapter->pool.gid_pn_req)
359                 return -ENOMEM;
360
361         adapter->pool.scsi_req =
362                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
363         if (!adapter->pool.scsi_req)
364                 return -ENOMEM;
365
366         adapter->pool.scsi_abort =
367                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
368         if (!adapter->pool.scsi_abort)
369                 return -ENOMEM;
370
371         adapter->pool.status_read_req =
372                 mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
373                                             sizeof(struct zfcp_fsf_req));
374         if (!adapter->pool.status_read_req)
375                 return -ENOMEM;
376
377         adapter->pool.qtcb_pool =
378                 mempool_create_slab_pool(4, zfcp_data.qtcb_cache);
379         if (!adapter->pool.qtcb_pool)
380                 return -ENOMEM;
381
382         adapter->pool.status_read_data =
383                 mempool_create_slab_pool(FSF_STATUS_READS_RECOM,
384                                          zfcp_data.sr_buffer_cache);
385         if (!adapter->pool.status_read_data)
386                 return -ENOMEM;
387
388         adapter->pool.gid_pn =
389                 mempool_create_slab_pool(1, zfcp_data.gid_pn_cache);
390         if (!adapter->pool.gid_pn)
391                 return -ENOMEM;
392
393         return 0;
394 }
395
396 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
397 {
398         if (adapter->pool.erp_req)
399                 mempool_destroy(adapter->pool.erp_req);
400         if (adapter->pool.scsi_req)
401                 mempool_destroy(adapter->pool.scsi_req);
402         if (adapter->pool.scsi_abort)
403                 mempool_destroy(adapter->pool.scsi_abort);
404         if (adapter->pool.qtcb_pool)
405                 mempool_destroy(adapter->pool.qtcb_pool);
406         if (adapter->pool.status_read_req)
407                 mempool_destroy(adapter->pool.status_read_req);
408         if (adapter->pool.status_read_data)
409                 mempool_destroy(adapter->pool.status_read_data);
410         if (adapter->pool.gid_pn)
411                 mempool_destroy(adapter->pool.gid_pn);
412 }
413
414 /**
415  * zfcp_status_read_refill - refill the long running status_read_requests
416  * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
417  *
418  * Returns: 0 on success, 1 otherwise
419  *
420  * if there are 16 or more status_read requests missing an adapter_reopen
421  * is triggered
422  */
423 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
424 {
425         while (atomic_read(&adapter->stat_miss) > 0)
426                 if (zfcp_fsf_status_read(adapter->qdio)) {
427                         if (atomic_read(&adapter->stat_miss) >= 16) {
428                                 zfcp_erp_adapter_reopen(adapter, 0, "axsref1",
429                                                         NULL);
430                                 return 1;
431                         }
432                         break;
433                 } else
434                         atomic_dec(&adapter->stat_miss);
435         return 0;
436 }
437
438 static void _zfcp_status_read_scheduler(struct work_struct *work)
439 {
440         zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
441                                              stat_work));
442 }
443
444 static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
445 {
446         struct zfcp_adapter *adapter =
447                 container_of(sl, struct zfcp_adapter, service_level);
448
449         seq_printf(m, "zfcp: %s microcode level %x\n",
450                    dev_name(&adapter->ccw_device->dev),
451                    adapter->fsf_lic_version);
452 }
453
454 static int zfcp_setup_adapter_work_queue(struct zfcp_adapter *adapter)
455 {
456         char name[TASK_COMM_LEN];
457
458         snprintf(name, sizeof(name), "zfcp_q_%s",
459                  dev_name(&adapter->ccw_device->dev));
460         adapter->work_queue = create_singlethread_workqueue(name);
461
462         if (adapter->work_queue)
463                 return 0;
464         return -ENOMEM;
465 }
466
467 static void zfcp_destroy_adapter_work_queue(struct zfcp_adapter *adapter)
468 {
469         if (adapter->work_queue)
470                 destroy_workqueue(adapter->work_queue);
471         adapter->work_queue = NULL;
472
473 }
474
475 /**
476  * zfcp_adapter_enqueue - enqueue a new adapter to the list
477  * @ccw_device: pointer to the struct cc_device
478  *
479  * Returns:     struct zfcp_adapter*
480  * Enqueues an adapter at the end of the adapter list in the driver data.
481  * All adapter internal structures are set up.
482  * Proc-fs entries are also created.
483  */
484 struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
485 {
486         struct zfcp_adapter *adapter;
487
488         if (!get_device(&ccw_device->dev))
489                 return ERR_PTR(-ENODEV);
490
491         adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
492         if (!adapter) {
493                 put_device(&ccw_device->dev);
494                 return ERR_PTR(-ENOMEM);
495         }
496
497         kref_init(&adapter->ref);
498
499         ccw_device->handler = NULL;
500         adapter->ccw_device = ccw_device;
501
502         INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
503         INIT_WORK(&adapter->scan_work, zfcp_fc_scan_ports);
504
505         if (zfcp_qdio_setup(adapter))
506                 goto failed;
507
508         if (zfcp_allocate_low_mem_buffers(adapter))
509                 goto failed;
510
511         adapter->req_list = zfcp_reqlist_alloc();
512         if (!adapter->req_list)
513                 goto failed;
514
515         if (zfcp_dbf_adapter_register(adapter))
516                 goto failed;
517
518         if (zfcp_setup_adapter_work_queue(adapter))
519                 goto failed;
520
521         if (zfcp_fc_gs_setup(adapter))
522                 goto failed;
523
524         rwlock_init(&adapter->port_list_lock);
525         INIT_LIST_HEAD(&adapter->port_list);
526
527         init_waitqueue_head(&adapter->erp_ready_wq);
528         init_waitqueue_head(&adapter->erp_done_wqh);
529
530         INIT_LIST_HEAD(&adapter->erp_ready_head);
531         INIT_LIST_HEAD(&adapter->erp_running_head);
532
533         rwlock_init(&adapter->erp_lock);
534         rwlock_init(&adapter->abort_lock);
535
536         if (zfcp_erp_thread_setup(adapter))
537                 goto failed;
538
539         adapter->service_level.seq_print = zfcp_print_sl;
540
541         dev_set_drvdata(&ccw_device->dev, adapter);
542
543         if (sysfs_create_group(&ccw_device->dev.kobj,
544                                &zfcp_sysfs_adapter_attrs))
545                 goto failed;
546
547         if (!zfcp_adapter_scsi_register(adapter))
548                 return adapter;
549
550 failed:
551         zfcp_adapter_unregister(adapter);
552         return ERR_PTR(-ENOMEM);
553 }
554
555 void zfcp_adapter_unregister(struct zfcp_adapter *adapter)
556 {
557         struct ccw_device *cdev = adapter->ccw_device;
558
559         cancel_work_sync(&adapter->scan_work);
560         cancel_work_sync(&adapter->stat_work);
561         zfcp_destroy_adapter_work_queue(adapter);
562
563         zfcp_fc_wka_ports_force_offline(adapter->gs);
564         zfcp_adapter_scsi_unregister(adapter);
565         sysfs_remove_group(&cdev->dev.kobj, &zfcp_sysfs_adapter_attrs);
566
567         zfcp_erp_thread_kill(adapter);
568         zfcp_dbf_adapter_unregister(adapter->dbf);
569         zfcp_qdio_destroy(adapter->qdio);
570
571         zfcp_ccw_adapter_put(adapter); /* final put to release */
572 }
573
574 /**
575  * zfcp_adapter_release - remove the adapter from the resource list
576  * @ref: pointer to struct kref
577  * locks:       adapter list write lock is assumed to be held by caller
578  */
579 void zfcp_adapter_release(struct kref *ref)
580 {
581         struct zfcp_adapter *adapter = container_of(ref, struct zfcp_adapter,
582                                                     ref);
583         struct ccw_device *cdev = adapter->ccw_device;
584
585         dev_set_drvdata(&adapter->ccw_device->dev, NULL);
586         zfcp_fc_gs_destroy(adapter);
587         zfcp_free_low_mem_buffers(adapter);
588         kfree(adapter->req_list);
589         kfree(adapter->fc_stats);
590         kfree(adapter->stats_reset_data);
591         kfree(adapter);
592         put_device(&cdev->dev);
593 }
594
595 /**
596  * zfcp_device_unregister - remove port, unit from system
597  * @dev: reference to device which is to be removed
598  * @grp: related reference to attribute group
599  *
600  * Helper function to unregister port, unit from system
601  */
602 void zfcp_device_unregister(struct device *dev,
603                             const struct attribute_group *grp)
604 {
605         sysfs_remove_group(&dev->kobj, grp);
606         device_unregister(dev);
607 }
608
609 static void zfcp_port_release(struct device *dev)
610 {
611         struct zfcp_port *port = container_of(dev, struct zfcp_port, dev);
612
613         zfcp_ccw_adapter_put(port->adapter);
614         kfree(port);
615 }
616
617 /**
618  * zfcp_port_enqueue - enqueue port to port list of adapter
619  * @adapter: adapter where remote port is added
620  * @wwpn: WWPN of the remote port to be enqueued
621  * @status: initial status for the port
622  * @d_id: destination id of the remote port to be enqueued
623  * Returns: pointer to enqueued port on success, ERR_PTR on error
624  *
625  * All port internal structures are set up and the sysfs entry is generated.
626  * d_id is used to enqueue ports with a well known address like the Directory
627  * Service for nameserver lookup.
628  */
629 struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
630                                      u32 status, u32 d_id)
631 {
632         struct zfcp_port *port;
633         int retval = -ENOMEM;
634
635         kref_get(&adapter->ref);
636
637         port = zfcp_get_port_by_wwpn(adapter, wwpn);
638         if (port) {
639                 put_device(&port->dev);
640                 retval = -EEXIST;
641                 goto err_out;
642         }
643
644         port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
645         if (!port)
646                 goto err_out;
647
648         rwlock_init(&port->unit_list_lock);
649         INIT_LIST_HEAD(&port->unit_list);
650
651         INIT_WORK(&port->gid_pn_work, zfcp_fc_port_did_lookup);
652         INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
653         INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
654
655         port->adapter = adapter;
656         port->d_id = d_id;
657         port->wwpn = wwpn;
658         port->rport_task = RPORT_NONE;
659         port->dev.parent = &adapter->ccw_device->dev;
660         port->dev.release = zfcp_port_release;
661
662         if (dev_set_name(&port->dev, "0x%016llx", (unsigned long long)wwpn)) {
663                 kfree(port);
664                 goto err_out;
665         }
666         retval = -EINVAL;
667
668         if (device_register(&port->dev)) {
669                 put_device(&port->dev);
670                 goto err_out;
671         }
672
673         if (sysfs_create_group(&port->dev.kobj,
674                                &zfcp_sysfs_port_attrs))
675                 goto err_out_put;
676
677         write_lock_irq(&adapter->port_list_lock);
678         list_add_tail(&port->list, &adapter->port_list);
679         write_unlock_irq(&adapter->port_list_lock);
680
681         atomic_set_mask(status | ZFCP_STATUS_COMMON_RUNNING, &port->status);
682
683         return port;
684
685 err_out_put:
686         device_unregister(&port->dev);
687 err_out:
688         zfcp_ccw_adapter_put(adapter);
689         return ERR_PTR(retval);
690 }
691
692 /**
693  * zfcp_sg_free_table - free memory used by scatterlists
694  * @sg: pointer to scatterlist
695  * @count: number of scatterlist which are to be free'ed
696  * the scatterlist are expected to reference pages always
697  */
698 void zfcp_sg_free_table(struct scatterlist *sg, int count)
699 {
700         int i;
701
702         for (i = 0; i < count; i++, sg++)
703                 if (sg)
704                         free_page((unsigned long) sg_virt(sg));
705                 else
706                         break;
707 }
708
709 /**
710  * zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
711  * @sg: pointer to struct scatterlist
712  * @count: number of scatterlists which should be assigned with buffers
713  * of size page
714  *
715  * Returns: 0 on success, -ENOMEM otherwise
716  */
717 int zfcp_sg_setup_table(struct scatterlist *sg, int count)
718 {
719         void *addr;
720         int i;
721
722         sg_init_table(sg, count);
723         for (i = 0; i < count; i++, sg++) {
724                 addr = (void *) get_zeroed_page(GFP_KERNEL);
725                 if (!addr) {
726                         zfcp_sg_free_table(sg, i);
727                         return -ENOMEM;
728                 }
729                 sg_set_buf(sg, addr, PAGE_SIZE);
730         }
731         return 0;
732 }