[SCSI] zfcp: Issue FCP command without holding SCSI host_lock
[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 <linux/slab.h>
34 #include "zfcp_ext.h"
35 #include "zfcp_fc.h"
36 #include "zfcp_reqlist.h"
37
38 #define ZFCP_BUS_ID_SIZE        20
39
40 MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
41 MODULE_DESCRIPTION("FCP HBA driver");
42 MODULE_LICENSE("GPL");
43
44 static char *init_device;
45 module_param_named(device, init_device, charp, 0400);
46 MODULE_PARM_DESC(device, "specify initial device");
47
48 static struct kmem_cache *zfcp_cache_hw_align(const char *name,
49                                               unsigned long size)
50 {
51         return kmem_cache_create(name, size, roundup_pow_of_two(size), 0, NULL);
52 }
53
54 static void __init zfcp_init_device_configure(char *busid, u64 wwpn, u64 lun)
55 {
56         struct ccw_device *cdev;
57         struct zfcp_adapter *adapter;
58         struct zfcp_port *port;
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         flush_work(&port->rport_work);
75
76         zfcp_unit_add(port, lun);
77         put_device(&port->dev);
78
79 out_port:
80         zfcp_ccw_adapter_put(adapter);
81 out_ccw_device:
82         put_device(&cdev->dev);
83         return;
84 }
85
86 static void __init zfcp_init_device_setup(char *devstr)
87 {
88         char *token;
89         char *str, *str_saved;
90         char busid[ZFCP_BUS_ID_SIZE];
91         u64 wwpn, lun;
92
93         /* duplicate devstr and keep the original for sysfs presentation*/
94         str_saved = kstrdup(devstr, GFP_KERNEL);
95         str = str_saved;
96         if (!str)
97                 return;
98
99         token = strsep(&str, ",");
100         if (!token || strlen(token) >= ZFCP_BUS_ID_SIZE)
101                 goto err_out;
102         strncpy(busid, token, ZFCP_BUS_ID_SIZE);
103
104         token = strsep(&str, ",");
105         if (!token || strict_strtoull(token, 0, (unsigned long long *) &wwpn))
106                 goto err_out;
107
108         token = strsep(&str, ",");
109         if (!token || strict_strtoull(token, 0, (unsigned long long *) &lun))
110                 goto err_out;
111
112         kfree(str_saved);
113         zfcp_init_device_configure(busid, wwpn, lun);
114         return;
115
116 err_out:
117         kfree(str_saved);
118         pr_err("%s is not a valid SCSI device\n", devstr);
119 }
120
121 static int __init zfcp_module_init(void)
122 {
123         int retval = -ENOMEM;
124
125         zfcp_data.gpn_ft_cache = zfcp_cache_hw_align("zfcp_gpn",
126                                         sizeof(struct zfcp_fc_gpn_ft_req));
127         if (!zfcp_data.gpn_ft_cache)
128                 goto out;
129
130         zfcp_data.qtcb_cache = zfcp_cache_hw_align("zfcp_qtcb",
131                                         sizeof(struct fsf_qtcb));
132         if (!zfcp_data.qtcb_cache)
133                 goto out_qtcb_cache;
134
135         zfcp_data.sr_buffer_cache = zfcp_cache_hw_align("zfcp_sr",
136                                         sizeof(struct fsf_status_read_buffer));
137         if (!zfcp_data.sr_buffer_cache)
138                 goto out_sr_cache;
139
140         zfcp_data.gid_pn_cache = zfcp_cache_hw_align("zfcp_gid",
141                                         sizeof(struct zfcp_fc_gid_pn));
142         if (!zfcp_data.gid_pn_cache)
143                 goto out_gid_cache;
144
145         zfcp_data.adisc_cache = zfcp_cache_hw_align("zfcp_adisc",
146                                         sizeof(struct zfcp_fc_els_adisc));
147         if (!zfcp_data.adisc_cache)
148                 goto out_adisc_cache;
149
150         zfcp_data.scsi_transport_template =
151                 fc_attach_transport(&zfcp_transport_functions);
152         if (!zfcp_data.scsi_transport_template)
153                 goto out_transport;
154         scsi_transport_reserve_device(zfcp_data.scsi_transport_template,
155                                       sizeof(struct zfcp_scsi_dev));
156
157
158         retval = misc_register(&zfcp_cfdc_misc);
159         if (retval) {
160                 pr_err("Registering the misc device zfcp_cfdc failed\n");
161                 goto out_misc;
162         }
163
164         retval = ccw_driver_register(&zfcp_ccw_driver);
165         if (retval) {
166                 pr_err("The zfcp device driver could not register with "
167                        "the common I/O layer\n");
168                 goto out_ccw_register;
169         }
170
171         if (init_device)
172                 zfcp_init_device_setup(init_device);
173         return 0;
174
175 out_ccw_register:
176         misc_deregister(&zfcp_cfdc_misc);
177 out_misc:
178         fc_release_transport(zfcp_data.scsi_transport_template);
179 out_transport:
180         kmem_cache_destroy(zfcp_data.adisc_cache);
181 out_adisc_cache:
182         kmem_cache_destroy(zfcp_data.gid_pn_cache);
183 out_gid_cache:
184         kmem_cache_destroy(zfcp_data.sr_buffer_cache);
185 out_sr_cache:
186         kmem_cache_destroy(zfcp_data.qtcb_cache);
187 out_qtcb_cache:
188         kmem_cache_destroy(zfcp_data.gpn_ft_cache);
189 out:
190         return retval;
191 }
192
193 module_init(zfcp_module_init);
194
195 static void __exit zfcp_module_exit(void)
196 {
197         ccw_driver_unregister(&zfcp_ccw_driver);
198         misc_deregister(&zfcp_cfdc_misc);
199         fc_release_transport(zfcp_data.scsi_transport_template);
200         kmem_cache_destroy(zfcp_data.adisc_cache);
201         kmem_cache_destroy(zfcp_data.gid_pn_cache);
202         kmem_cache_destroy(zfcp_data.sr_buffer_cache);
203         kmem_cache_destroy(zfcp_data.qtcb_cache);
204         kmem_cache_destroy(zfcp_data.gpn_ft_cache);
205 }
206
207 module_exit(zfcp_module_exit);
208
209 /**
210  * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
211  * @adapter: pointer to adapter to search for port
212  * @wwpn: wwpn to search for
213  *
214  * Returns: pointer to zfcp_port or NULL
215  */
216 struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
217                                         u64 wwpn)
218 {
219         unsigned long flags;
220         struct zfcp_port *port;
221
222         read_lock_irqsave(&adapter->port_list_lock, flags);
223         list_for_each_entry(port, &adapter->port_list, list)
224                 if (port->wwpn == wwpn) {
225                         if (!get_device(&port->dev))
226                                 port = NULL;
227                         read_unlock_irqrestore(&adapter->port_list_lock, flags);
228                         return port;
229                 }
230         read_unlock_irqrestore(&adapter->port_list_lock, flags);
231         return NULL;
232 }
233
234 static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
235 {
236         adapter->pool.erp_req =
237                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
238         if (!adapter->pool.erp_req)
239                 return -ENOMEM;
240
241         adapter->pool.gid_pn_req =
242                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
243         if (!adapter->pool.gid_pn_req)
244                 return -ENOMEM;
245
246         adapter->pool.scsi_req =
247                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
248         if (!adapter->pool.scsi_req)
249                 return -ENOMEM;
250
251         adapter->pool.scsi_abort =
252                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
253         if (!adapter->pool.scsi_abort)
254                 return -ENOMEM;
255
256         adapter->pool.status_read_req =
257                 mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
258                                             sizeof(struct zfcp_fsf_req));
259         if (!adapter->pool.status_read_req)
260                 return -ENOMEM;
261
262         adapter->pool.qtcb_pool =
263                 mempool_create_slab_pool(4, zfcp_data.qtcb_cache);
264         if (!adapter->pool.qtcb_pool)
265                 return -ENOMEM;
266
267         adapter->pool.status_read_data =
268                 mempool_create_slab_pool(FSF_STATUS_READS_RECOM,
269                                          zfcp_data.sr_buffer_cache);
270         if (!adapter->pool.status_read_data)
271                 return -ENOMEM;
272
273         adapter->pool.gid_pn =
274                 mempool_create_slab_pool(1, zfcp_data.gid_pn_cache);
275         if (!adapter->pool.gid_pn)
276                 return -ENOMEM;
277
278         return 0;
279 }
280
281 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
282 {
283         if (adapter->pool.erp_req)
284                 mempool_destroy(adapter->pool.erp_req);
285         if (adapter->pool.scsi_req)
286                 mempool_destroy(adapter->pool.scsi_req);
287         if (adapter->pool.scsi_abort)
288                 mempool_destroy(adapter->pool.scsi_abort);
289         if (adapter->pool.qtcb_pool)
290                 mempool_destroy(adapter->pool.qtcb_pool);
291         if (adapter->pool.status_read_req)
292                 mempool_destroy(adapter->pool.status_read_req);
293         if (adapter->pool.status_read_data)
294                 mempool_destroy(adapter->pool.status_read_data);
295         if (adapter->pool.gid_pn)
296                 mempool_destroy(adapter->pool.gid_pn);
297 }
298
299 /**
300  * zfcp_status_read_refill - refill the long running status_read_requests
301  * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
302  *
303  * Returns: 0 on success, 1 otherwise
304  *
305  * if there are 16 or more status_read requests missing an adapter_reopen
306  * is triggered
307  */
308 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
309 {
310         while (atomic_read(&adapter->stat_miss) > 0)
311                 if (zfcp_fsf_status_read(adapter->qdio)) {
312                         if (atomic_read(&adapter->stat_miss) >=
313                             adapter->stat_read_buf_num) {
314                                 zfcp_erp_adapter_reopen(adapter, 0, "axsref1",
315                                                         NULL);
316                                 return 1;
317                         }
318                         break;
319                 } else
320                         atomic_dec(&adapter->stat_miss);
321         return 0;
322 }
323
324 static void _zfcp_status_read_scheduler(struct work_struct *work)
325 {
326         zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
327                                              stat_work));
328 }
329
330 static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
331 {
332         struct zfcp_adapter *adapter =
333                 container_of(sl, struct zfcp_adapter, service_level);
334
335         seq_printf(m, "zfcp: %s microcode level %x\n",
336                    dev_name(&adapter->ccw_device->dev),
337                    adapter->fsf_lic_version);
338 }
339
340 static int zfcp_setup_adapter_work_queue(struct zfcp_adapter *adapter)
341 {
342         char name[TASK_COMM_LEN];
343
344         snprintf(name, sizeof(name), "zfcp_q_%s",
345                  dev_name(&adapter->ccw_device->dev));
346         adapter->work_queue = create_singlethread_workqueue(name);
347
348         if (adapter->work_queue)
349                 return 0;
350         return -ENOMEM;
351 }
352
353 static void zfcp_destroy_adapter_work_queue(struct zfcp_adapter *adapter)
354 {
355         if (adapter->work_queue)
356                 destroy_workqueue(adapter->work_queue);
357         adapter->work_queue = NULL;
358
359 }
360
361 /**
362  * zfcp_adapter_enqueue - enqueue a new adapter to the list
363  * @ccw_device: pointer to the struct cc_device
364  *
365  * Returns:     struct zfcp_adapter*
366  * Enqueues an adapter at the end of the adapter list in the driver data.
367  * All adapter internal structures are set up.
368  * Proc-fs entries are also created.
369  */
370 struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
371 {
372         struct zfcp_adapter *adapter;
373
374         if (!get_device(&ccw_device->dev))
375                 return ERR_PTR(-ENODEV);
376
377         adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
378         if (!adapter) {
379                 put_device(&ccw_device->dev);
380                 return ERR_PTR(-ENOMEM);
381         }
382
383         kref_init(&adapter->ref);
384
385         ccw_device->handler = NULL;
386         adapter->ccw_device = ccw_device;
387
388         INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
389         INIT_WORK(&adapter->scan_work, zfcp_fc_scan_ports);
390
391         if (zfcp_qdio_setup(adapter))
392                 goto failed;
393
394         if (zfcp_allocate_low_mem_buffers(adapter))
395                 goto failed;
396
397         adapter->req_list = zfcp_reqlist_alloc();
398         if (!adapter->req_list)
399                 goto failed;
400
401         if (zfcp_dbf_adapter_register(adapter))
402                 goto failed;
403
404         if (zfcp_setup_adapter_work_queue(adapter))
405                 goto failed;
406
407         if (zfcp_fc_gs_setup(adapter))
408                 goto failed;
409
410         rwlock_init(&adapter->port_list_lock);
411         INIT_LIST_HEAD(&adapter->port_list);
412
413         INIT_LIST_HEAD(&adapter->events.list);
414         INIT_WORK(&adapter->events.work, zfcp_fc_post_event);
415         spin_lock_init(&adapter->events.list_lock);
416
417         init_waitqueue_head(&adapter->erp_ready_wq);
418         init_waitqueue_head(&adapter->erp_done_wqh);
419
420         INIT_LIST_HEAD(&adapter->erp_ready_head);
421         INIT_LIST_HEAD(&adapter->erp_running_head);
422
423         rwlock_init(&adapter->erp_lock);
424         rwlock_init(&adapter->abort_lock);
425
426         if (zfcp_erp_thread_setup(adapter))
427                 goto failed;
428
429         adapter->service_level.seq_print = zfcp_print_sl;
430
431         dev_set_drvdata(&ccw_device->dev, adapter);
432
433         if (sysfs_create_group(&ccw_device->dev.kobj,
434                                &zfcp_sysfs_adapter_attrs))
435                 goto failed;
436
437         /* report size limit per scatter-gather segment */
438         adapter->dma_parms.max_segment_size = ZFCP_QDIO_SBALE_LEN;
439         adapter->ccw_device->dev.dma_parms = &adapter->dma_parms;
440
441         if (!zfcp_adapter_scsi_register(adapter))
442                 return adapter;
443
444 failed:
445         zfcp_adapter_unregister(adapter);
446         return ERR_PTR(-ENOMEM);
447 }
448
449 void zfcp_adapter_unregister(struct zfcp_adapter *adapter)
450 {
451         struct ccw_device *cdev = adapter->ccw_device;
452
453         cancel_work_sync(&adapter->scan_work);
454         cancel_work_sync(&adapter->stat_work);
455         zfcp_destroy_adapter_work_queue(adapter);
456
457         zfcp_fc_wka_ports_force_offline(adapter->gs);
458         zfcp_adapter_scsi_unregister(adapter);
459         sysfs_remove_group(&cdev->dev.kobj, &zfcp_sysfs_adapter_attrs);
460
461         zfcp_erp_thread_kill(adapter);
462         zfcp_dbf_adapter_unregister(adapter->dbf);
463         zfcp_qdio_destroy(adapter->qdio);
464
465         zfcp_ccw_adapter_put(adapter); /* final put to release */
466 }
467
468 /**
469  * zfcp_adapter_release - remove the adapter from the resource list
470  * @ref: pointer to struct kref
471  * locks:       adapter list write lock is assumed to be held by caller
472  */
473 void zfcp_adapter_release(struct kref *ref)
474 {
475         struct zfcp_adapter *adapter = container_of(ref, struct zfcp_adapter,
476                                                     ref);
477         struct ccw_device *cdev = adapter->ccw_device;
478
479         dev_set_drvdata(&adapter->ccw_device->dev, NULL);
480         zfcp_fc_gs_destroy(adapter);
481         zfcp_free_low_mem_buffers(adapter);
482         kfree(adapter->req_list);
483         kfree(adapter->fc_stats);
484         kfree(adapter->stats_reset_data);
485         kfree(adapter);
486         put_device(&cdev->dev);
487 }
488
489 /**
490  * zfcp_device_unregister - remove port, unit from system
491  * @dev: reference to device which is to be removed
492  * @grp: related reference to attribute group
493  *
494  * Helper function to unregister port, unit from system
495  */
496 void zfcp_device_unregister(struct device *dev,
497                             const struct attribute_group *grp)
498 {
499         sysfs_remove_group(&dev->kobj, grp);
500         device_unregister(dev);
501 }
502
503 static void zfcp_port_release(struct device *dev)
504 {
505         struct zfcp_port *port = container_of(dev, struct zfcp_port, dev);
506
507         zfcp_ccw_adapter_put(port->adapter);
508         kfree(port);
509 }
510
511 /**
512  * zfcp_port_enqueue - enqueue port to port list of adapter
513  * @adapter: adapter where remote port is added
514  * @wwpn: WWPN of the remote port to be enqueued
515  * @status: initial status for the port
516  * @d_id: destination id of the remote port to be enqueued
517  * Returns: pointer to enqueued port on success, ERR_PTR on error
518  *
519  * All port internal structures are set up and the sysfs entry is generated.
520  * d_id is used to enqueue ports with a well known address like the Directory
521  * Service for nameserver lookup.
522  */
523 struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
524                                      u32 status, u32 d_id)
525 {
526         struct zfcp_port *port;
527         int retval = -ENOMEM;
528
529         kref_get(&adapter->ref);
530
531         port = zfcp_get_port_by_wwpn(adapter, wwpn);
532         if (port) {
533                 put_device(&port->dev);
534                 retval = -EEXIST;
535                 goto err_out;
536         }
537
538         port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
539         if (!port)
540                 goto err_out;
541
542         rwlock_init(&port->unit_list_lock);
543         INIT_LIST_HEAD(&port->unit_list);
544
545         INIT_WORK(&port->gid_pn_work, zfcp_fc_port_did_lookup);
546         INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
547         INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
548
549         port->adapter = adapter;
550         port->d_id = d_id;
551         port->wwpn = wwpn;
552         port->rport_task = RPORT_NONE;
553         port->dev.parent = &adapter->ccw_device->dev;
554         port->dev.release = zfcp_port_release;
555
556         if (dev_set_name(&port->dev, "0x%016llx", (unsigned long long)wwpn)) {
557                 kfree(port);
558                 goto err_out;
559         }
560         retval = -EINVAL;
561
562         if (device_register(&port->dev)) {
563                 put_device(&port->dev);
564                 goto err_out;
565         }
566
567         if (sysfs_create_group(&port->dev.kobj,
568                                &zfcp_sysfs_port_attrs))
569                 goto err_out_put;
570
571         write_lock_irq(&adapter->port_list_lock);
572         list_add_tail(&port->list, &adapter->port_list);
573         write_unlock_irq(&adapter->port_list_lock);
574
575         atomic_set_mask(status | ZFCP_STATUS_COMMON_RUNNING, &port->status);
576
577         return port;
578
579 err_out_put:
580         device_unregister(&port->dev);
581 err_out:
582         zfcp_ccw_adapter_put(adapter);
583         return ERR_PTR(retval);
584 }
585
586 /**
587  * zfcp_sg_free_table - free memory used by scatterlists
588  * @sg: pointer to scatterlist
589  * @count: number of scatterlist which are to be free'ed
590  * the scatterlist are expected to reference pages always
591  */
592 void zfcp_sg_free_table(struct scatterlist *sg, int count)
593 {
594         int i;
595
596         for (i = 0; i < count; i++, sg++)
597                 if (sg)
598                         free_page((unsigned long) sg_virt(sg));
599                 else
600                         break;
601 }
602
603 /**
604  * zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
605  * @sg: pointer to struct scatterlist
606  * @count: number of scatterlists which should be assigned with buffers
607  * of size page
608  *
609  * Returns: 0 on success, -ENOMEM otherwise
610  */
611 int zfcp_sg_setup_table(struct scatterlist *sg, int count)
612 {
613         void *addr;
614         int i;
615
616         sg_init_table(sg, count);
617         for (i = 0; i < count; i++, sg++) {
618                 addr = (void *) get_zeroed_page(GFP_KERNEL);
619                 if (!addr) {
620                         zfcp_sg_free_table(sg, i);
621                         return -ENOMEM;
622                 }
623                 sg_set_buf(sg, addr, PAGE_SIZE);
624         }
625         return 0;
626 }