Merge branch 'kvm-updates/2.6.39' of git://git.kernel.org/pub/scm/virt/kvm/kvm
[pandora-kernel.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 * __init 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_fsf_qtcb_cache = zfcp_cache_hw_align("zfcp_fsf_qtcb",
126                                                   sizeof(struct fsf_qtcb));
127         if (!zfcp_fsf_qtcb_cache)
128                 goto out_qtcb_cache;
129
130         zfcp_fc_req_cache = zfcp_cache_hw_align("zfcp_fc_req",
131                                                 sizeof(struct zfcp_fc_req));
132         if (!zfcp_fc_req_cache)
133                 goto out_fc_cache;
134
135         zfcp_scsi_transport_template =
136                 fc_attach_transport(&zfcp_transport_functions);
137         if (!zfcp_scsi_transport_template)
138                 goto out_transport;
139         scsi_transport_reserve_device(zfcp_scsi_transport_template,
140                                       sizeof(struct zfcp_scsi_dev));
141
142
143         retval = misc_register(&zfcp_cfdc_misc);
144         if (retval) {
145                 pr_err("Registering the misc device zfcp_cfdc failed\n");
146                 goto out_misc;
147         }
148
149         retval = ccw_driver_register(&zfcp_ccw_driver);
150         if (retval) {
151                 pr_err("The zfcp device driver could not register with "
152                        "the common I/O layer\n");
153                 goto out_ccw_register;
154         }
155
156         if (init_device)
157                 zfcp_init_device_setup(init_device);
158         return 0;
159
160 out_ccw_register:
161         misc_deregister(&zfcp_cfdc_misc);
162 out_misc:
163         fc_release_transport(zfcp_scsi_transport_template);
164 out_transport:
165         kmem_cache_destroy(zfcp_fc_req_cache);
166 out_fc_cache:
167         kmem_cache_destroy(zfcp_fsf_qtcb_cache);
168 out_qtcb_cache:
169         return retval;
170 }
171
172 module_init(zfcp_module_init);
173
174 static void __exit zfcp_module_exit(void)
175 {
176         ccw_driver_unregister(&zfcp_ccw_driver);
177         misc_deregister(&zfcp_cfdc_misc);
178         fc_release_transport(zfcp_scsi_transport_template);
179         kmem_cache_destroy(zfcp_fc_req_cache);
180         kmem_cache_destroy(zfcp_fsf_qtcb_cache);
181 }
182
183 module_exit(zfcp_module_exit);
184
185 /**
186  * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
187  * @adapter: pointer to adapter to search for port
188  * @wwpn: wwpn to search for
189  *
190  * Returns: pointer to zfcp_port or NULL
191  */
192 struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
193                                         u64 wwpn)
194 {
195         unsigned long flags;
196         struct zfcp_port *port;
197
198         read_lock_irqsave(&adapter->port_list_lock, flags);
199         list_for_each_entry(port, &adapter->port_list, list)
200                 if (port->wwpn == wwpn) {
201                         if (!get_device(&port->dev))
202                                 port = NULL;
203                         read_unlock_irqrestore(&adapter->port_list_lock, flags);
204                         return port;
205                 }
206         read_unlock_irqrestore(&adapter->port_list_lock, flags);
207         return NULL;
208 }
209
210 static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
211 {
212         adapter->pool.erp_req =
213                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
214         if (!adapter->pool.erp_req)
215                 return -ENOMEM;
216
217         adapter->pool.gid_pn_req =
218                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
219         if (!adapter->pool.gid_pn_req)
220                 return -ENOMEM;
221
222         adapter->pool.scsi_req =
223                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
224         if (!adapter->pool.scsi_req)
225                 return -ENOMEM;
226
227         adapter->pool.scsi_abort =
228                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
229         if (!adapter->pool.scsi_abort)
230                 return -ENOMEM;
231
232         adapter->pool.status_read_req =
233                 mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
234                                             sizeof(struct zfcp_fsf_req));
235         if (!adapter->pool.status_read_req)
236                 return -ENOMEM;
237
238         adapter->pool.qtcb_pool =
239                 mempool_create_slab_pool(4, zfcp_fsf_qtcb_cache);
240         if (!adapter->pool.qtcb_pool)
241                 return -ENOMEM;
242
243         BUILD_BUG_ON(sizeof(struct fsf_status_read_buffer) > PAGE_SIZE);
244         adapter->pool.sr_data =
245                 mempool_create_page_pool(FSF_STATUS_READS_RECOM, 0);
246         if (!adapter->pool.sr_data)
247                 return -ENOMEM;
248
249         adapter->pool.gid_pn =
250                 mempool_create_slab_pool(1, zfcp_fc_req_cache);
251         if (!adapter->pool.gid_pn)
252                 return -ENOMEM;
253
254         return 0;
255 }
256
257 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
258 {
259         if (adapter->pool.erp_req)
260                 mempool_destroy(adapter->pool.erp_req);
261         if (adapter->pool.scsi_req)
262                 mempool_destroy(adapter->pool.scsi_req);
263         if (adapter->pool.scsi_abort)
264                 mempool_destroy(adapter->pool.scsi_abort);
265         if (adapter->pool.qtcb_pool)
266                 mempool_destroy(adapter->pool.qtcb_pool);
267         if (adapter->pool.status_read_req)
268                 mempool_destroy(adapter->pool.status_read_req);
269         if (adapter->pool.sr_data)
270                 mempool_destroy(adapter->pool.sr_data);
271         if (adapter->pool.gid_pn)
272                 mempool_destroy(adapter->pool.gid_pn);
273 }
274
275 /**
276  * zfcp_status_read_refill - refill the long running status_read_requests
277  * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
278  *
279  * Returns: 0 on success, 1 otherwise
280  *
281  * if there are 16 or more status_read requests missing an adapter_reopen
282  * is triggered
283  */
284 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
285 {
286         while (atomic_read(&adapter->stat_miss) > 0)
287                 if (zfcp_fsf_status_read(adapter->qdio)) {
288                         if (atomic_read(&adapter->stat_miss) >=
289                             adapter->stat_read_buf_num) {
290                                 zfcp_erp_adapter_reopen(adapter, 0, "axsref1");
291                                 return 1;
292                         }
293                         break;
294                 } else
295                         atomic_dec(&adapter->stat_miss);
296         return 0;
297 }
298
299 static void _zfcp_status_read_scheduler(struct work_struct *work)
300 {
301         zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
302                                              stat_work));
303 }
304
305 static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
306 {
307         struct zfcp_adapter *adapter =
308                 container_of(sl, struct zfcp_adapter, service_level);
309
310         seq_printf(m, "zfcp: %s microcode level %x\n",
311                    dev_name(&adapter->ccw_device->dev),
312                    adapter->fsf_lic_version);
313 }
314
315 static int zfcp_setup_adapter_work_queue(struct zfcp_adapter *adapter)
316 {
317         char name[TASK_COMM_LEN];
318
319         snprintf(name, sizeof(name), "zfcp_q_%s",
320                  dev_name(&adapter->ccw_device->dev));
321         adapter->work_queue = create_singlethread_workqueue(name);
322
323         if (adapter->work_queue)
324                 return 0;
325         return -ENOMEM;
326 }
327
328 static void zfcp_destroy_adapter_work_queue(struct zfcp_adapter *adapter)
329 {
330         if (adapter->work_queue)
331                 destroy_workqueue(adapter->work_queue);
332         adapter->work_queue = NULL;
333
334 }
335
336 /**
337  * zfcp_adapter_enqueue - enqueue a new adapter to the list
338  * @ccw_device: pointer to the struct cc_device
339  *
340  * Returns:     struct zfcp_adapter*
341  * Enqueues an adapter at the end of the adapter list in the driver data.
342  * All adapter internal structures are set up.
343  * Proc-fs entries are also created.
344  */
345 struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
346 {
347         struct zfcp_adapter *adapter;
348
349         if (!get_device(&ccw_device->dev))
350                 return ERR_PTR(-ENODEV);
351
352         adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
353         if (!adapter) {
354                 put_device(&ccw_device->dev);
355                 return ERR_PTR(-ENOMEM);
356         }
357
358         kref_init(&adapter->ref);
359
360         ccw_device->handler = NULL;
361         adapter->ccw_device = ccw_device;
362
363         INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
364         INIT_WORK(&adapter->scan_work, zfcp_fc_scan_ports);
365         INIT_WORK(&adapter->ns_up_work, zfcp_fc_sym_name_update);
366
367         if (zfcp_qdio_setup(adapter))
368                 goto failed;
369
370         if (zfcp_allocate_low_mem_buffers(adapter))
371                 goto failed;
372
373         adapter->req_list = zfcp_reqlist_alloc();
374         if (!adapter->req_list)
375                 goto failed;
376
377         if (zfcp_dbf_adapter_register(adapter))
378                 goto failed;
379
380         if (zfcp_setup_adapter_work_queue(adapter))
381                 goto failed;
382
383         if (zfcp_fc_gs_setup(adapter))
384                 goto failed;
385
386         rwlock_init(&adapter->port_list_lock);
387         INIT_LIST_HEAD(&adapter->port_list);
388
389         INIT_LIST_HEAD(&adapter->events.list);
390         INIT_WORK(&adapter->events.work, zfcp_fc_post_event);
391         spin_lock_init(&adapter->events.list_lock);
392
393         init_waitqueue_head(&adapter->erp_ready_wq);
394         init_waitqueue_head(&adapter->erp_done_wqh);
395
396         INIT_LIST_HEAD(&adapter->erp_ready_head);
397         INIT_LIST_HEAD(&adapter->erp_running_head);
398
399         rwlock_init(&adapter->erp_lock);
400         rwlock_init(&adapter->abort_lock);
401
402         if (zfcp_erp_thread_setup(adapter))
403                 goto failed;
404
405         adapter->service_level.seq_print = zfcp_print_sl;
406
407         dev_set_drvdata(&ccw_device->dev, adapter);
408
409         if (sysfs_create_group(&ccw_device->dev.kobj,
410                                &zfcp_sysfs_adapter_attrs))
411                 goto failed;
412
413         /* report size limit per scatter-gather segment */
414         adapter->dma_parms.max_segment_size = ZFCP_QDIO_SBALE_LEN;
415         adapter->ccw_device->dev.dma_parms = &adapter->dma_parms;
416
417         if (!zfcp_scsi_adapter_register(adapter))
418                 return adapter;
419
420 failed:
421         zfcp_adapter_unregister(adapter);
422         return ERR_PTR(-ENOMEM);
423 }
424
425 void zfcp_adapter_unregister(struct zfcp_adapter *adapter)
426 {
427         struct ccw_device *cdev = adapter->ccw_device;
428
429         cancel_work_sync(&adapter->scan_work);
430         cancel_work_sync(&adapter->stat_work);
431         cancel_work_sync(&adapter->ns_up_work);
432         zfcp_destroy_adapter_work_queue(adapter);
433
434         zfcp_fc_wka_ports_force_offline(adapter->gs);
435         zfcp_scsi_adapter_unregister(adapter);
436         sysfs_remove_group(&cdev->dev.kobj, &zfcp_sysfs_adapter_attrs);
437
438         zfcp_erp_thread_kill(adapter);
439         zfcp_dbf_adapter_unregister(adapter);
440         zfcp_qdio_destroy(adapter->qdio);
441
442         zfcp_ccw_adapter_put(adapter); /* final put to release */
443 }
444
445 /**
446  * zfcp_adapter_release - remove the adapter from the resource list
447  * @ref: pointer to struct kref
448  * locks:       adapter list write lock is assumed to be held by caller
449  */
450 void zfcp_adapter_release(struct kref *ref)
451 {
452         struct zfcp_adapter *adapter = container_of(ref, struct zfcp_adapter,
453                                                     ref);
454         struct ccw_device *cdev = adapter->ccw_device;
455
456         dev_set_drvdata(&adapter->ccw_device->dev, NULL);
457         zfcp_fc_gs_destroy(adapter);
458         zfcp_free_low_mem_buffers(adapter);
459         kfree(adapter->req_list);
460         kfree(adapter->fc_stats);
461         kfree(adapter->stats_reset_data);
462         kfree(adapter);
463         put_device(&cdev->dev);
464 }
465
466 /**
467  * zfcp_device_unregister - remove port, unit from system
468  * @dev: reference to device which is to be removed
469  * @grp: related reference to attribute group
470  *
471  * Helper function to unregister port, unit from system
472  */
473 void zfcp_device_unregister(struct device *dev,
474                             const struct attribute_group *grp)
475 {
476         sysfs_remove_group(&dev->kobj, grp);
477         device_unregister(dev);
478 }
479
480 static void zfcp_port_release(struct device *dev)
481 {
482         struct zfcp_port *port = container_of(dev, struct zfcp_port, dev);
483
484         zfcp_ccw_adapter_put(port->adapter);
485         kfree(port);
486 }
487
488 /**
489  * zfcp_port_enqueue - enqueue port to port list of adapter
490  * @adapter: adapter where remote port is added
491  * @wwpn: WWPN of the remote port to be enqueued
492  * @status: initial status for the port
493  * @d_id: destination id of the remote port to be enqueued
494  * Returns: pointer to enqueued port on success, ERR_PTR on error
495  *
496  * All port internal structures are set up and the sysfs entry is generated.
497  * d_id is used to enqueue ports with a well known address like the Directory
498  * Service for nameserver lookup.
499  */
500 struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
501                                      u32 status, u32 d_id)
502 {
503         struct zfcp_port *port;
504         int retval = -ENOMEM;
505
506         kref_get(&adapter->ref);
507
508         port = zfcp_get_port_by_wwpn(adapter, wwpn);
509         if (port) {
510                 put_device(&port->dev);
511                 retval = -EEXIST;
512                 goto err_out;
513         }
514
515         port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
516         if (!port)
517                 goto err_out;
518
519         rwlock_init(&port->unit_list_lock);
520         INIT_LIST_HEAD(&port->unit_list);
521
522         INIT_WORK(&port->gid_pn_work, zfcp_fc_port_did_lookup);
523         INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
524         INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
525
526         port->adapter = adapter;
527         port->d_id = d_id;
528         port->wwpn = wwpn;
529         port->rport_task = RPORT_NONE;
530         port->dev.parent = &adapter->ccw_device->dev;
531         port->dev.release = zfcp_port_release;
532
533         if (dev_set_name(&port->dev, "0x%016llx", (unsigned long long)wwpn)) {
534                 kfree(port);
535                 goto err_out;
536         }
537         retval = -EINVAL;
538
539         if (device_register(&port->dev)) {
540                 put_device(&port->dev);
541                 goto err_out;
542         }
543
544         if (sysfs_create_group(&port->dev.kobj,
545                                &zfcp_sysfs_port_attrs))
546                 goto err_out_put;
547
548         write_lock_irq(&adapter->port_list_lock);
549         list_add_tail(&port->list, &adapter->port_list);
550         write_unlock_irq(&adapter->port_list_lock);
551
552         atomic_set_mask(status | ZFCP_STATUS_COMMON_RUNNING, &port->status);
553
554         return port;
555
556 err_out_put:
557         device_unregister(&port->dev);
558 err_out:
559         zfcp_ccw_adapter_put(adapter);
560         return ERR_PTR(retval);
561 }
562
563 /**
564  * zfcp_sg_free_table - free memory used by scatterlists
565  * @sg: pointer to scatterlist
566  * @count: number of scatterlist which are to be free'ed
567  * the scatterlist are expected to reference pages always
568  */
569 void zfcp_sg_free_table(struct scatterlist *sg, int count)
570 {
571         int i;
572
573         for (i = 0; i < count; i++, sg++)
574                 if (sg)
575                         free_page((unsigned long) sg_virt(sg));
576                 else
577                         break;
578 }
579
580 /**
581  * zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
582  * @sg: pointer to struct scatterlist
583  * @count: number of scatterlists which should be assigned with buffers
584  * of size page
585  *
586  * Returns: 0 on success, -ENOMEM otherwise
587  */
588 int zfcp_sg_setup_table(struct scatterlist *sg, int count)
589 {
590         void *addr;
591         int i;
592
593         sg_init_table(sg, count);
594         for (i = 0; i < count; i++, sg++) {
595                 addr = (void *) get_zeroed_page(GFP_KERNEL);
596                 if (!addr) {
597                         zfcp_sg_free_table(sg, i);
598                         return -ENOMEM;
599                 }
600                 sg_set_buf(sg, addr, PAGE_SIZE);
601         }
602         return 0;
603 }