xref: /openbmc/linux/drivers/s390/scsi/zfcp_aux.c (revision a44d924c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * zfcp device driver
4  *
5  * Module interface and handling of zfcp data structures.
6  *
7  * Copyright IBM Corp. 2002, 2017
8  */
9 
10 /*
11  * Driver authors:
12  *            Martin Peschke (originator of the driver)
13  *            Raimund Schroeder
14  *            Aron Zeh
15  *            Wolfgang Taphorn
16  *            Stefan Bader
17  *            Heiko Carstens (kernel 2.6 port of the driver)
18  *            Andreas Herrmann
19  *            Maxim Shchetynin
20  *            Volker Sameske
21  *            Ralph Wuerthner
22  *            Michael Loehr
23  *            Swen Schillig
24  *            Christof Schmitt
25  *            Martin Petermann
26  *            Sven Schuetz
27  *            Steffen Maier
28  */
29 
30 #define KMSG_COMPONENT "zfcp"
31 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
32 
33 #include <linux/seq_file.h>
34 #include <linux/slab.h>
35 #include <linux/module.h>
36 #include "zfcp_ext.h"
37 #include "zfcp_fc.h"
38 #include "zfcp_reqlist.h"
39 
40 #define ZFCP_BUS_ID_SIZE	20
41 
42 MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
43 MODULE_DESCRIPTION("FCP HBA driver");
44 MODULE_LICENSE("GPL");
45 
46 static char *init_device;
47 module_param_named(device, init_device, charp, 0400);
48 MODULE_PARM_DESC(device, "specify initial device");
49 
50 static struct kmem_cache * __init zfcp_cache_hw_align(const char *name,
51 						      unsigned long size)
52 {
53 	return kmem_cache_create(name, size, roundup_pow_of_two(size), 0, NULL);
54 }
55 
56 static void __init zfcp_init_device_configure(char *busid, u64 wwpn, u64 lun)
57 {
58 	struct ccw_device *cdev;
59 	struct zfcp_adapter *adapter;
60 	struct zfcp_port *port;
61 
62 	cdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
63 	if (!cdev)
64 		return;
65 
66 	if (ccw_device_set_online(cdev))
67 		goto out_ccw_device;
68 
69 	adapter = zfcp_ccw_adapter_by_cdev(cdev);
70 	if (!adapter)
71 		goto out_ccw_device;
72 
73 	port = zfcp_get_port_by_wwpn(adapter, wwpn);
74 	if (!port)
75 		goto out_port;
76 	flush_work(&port->rport_work);
77 
78 	zfcp_unit_add(port, lun);
79 	put_device(&port->dev);
80 
81 out_port:
82 	zfcp_ccw_adapter_put(adapter);
83 out_ccw_device:
84 	put_device(&cdev->dev);
85 	return;
86 }
87 
88 static void __init zfcp_init_device_setup(char *devstr)
89 {
90 	char *token;
91 	char *str, *str_saved;
92 	char busid[ZFCP_BUS_ID_SIZE];
93 	u64 wwpn, lun;
94 
95 	/* duplicate devstr and keep the original for sysfs presentation*/
96 	str_saved = kstrdup(devstr, GFP_KERNEL);
97 	str = str_saved;
98 	if (!str)
99 		return;
100 
101 	token = strsep(&str, ",");
102 	if (!token || strlen(token) >= ZFCP_BUS_ID_SIZE)
103 		goto err_out;
104 	strlcpy(busid, token, ZFCP_BUS_ID_SIZE);
105 
106 	token = strsep(&str, ",");
107 	if (!token || kstrtoull(token, 0, (unsigned long long *) &wwpn))
108 		goto err_out;
109 
110 	token = strsep(&str, ",");
111 	if (!token || kstrtoull(token, 0, (unsigned long long *) &lun))
112 		goto err_out;
113 
114 	kfree(str_saved);
115 	zfcp_init_device_configure(busid, wwpn, lun);
116 	return;
117 
118 err_out:
119 	kfree(str_saved);
120 	pr_err("%s is not a valid SCSI device\n", devstr);
121 }
122 
123 static int __init zfcp_module_init(void)
124 {
125 	int retval = -ENOMEM;
126 
127 	if (zfcp_experimental_dix)
128 		pr_warn("DIX is enabled. It is experimental and might cause problems\n");
129 
130 	zfcp_fsf_qtcb_cache = zfcp_cache_hw_align("zfcp_fsf_qtcb",
131 						  sizeof(struct fsf_qtcb));
132 	if (!zfcp_fsf_qtcb_cache)
133 		goto out_qtcb_cache;
134 
135 	zfcp_fc_req_cache = zfcp_cache_hw_align("zfcp_fc_req",
136 						sizeof(struct zfcp_fc_req));
137 	if (!zfcp_fc_req_cache)
138 		goto out_fc_cache;
139 
140 	zfcp_scsi_transport_template =
141 		fc_attach_transport(&zfcp_transport_functions);
142 	if (!zfcp_scsi_transport_template)
143 		goto out_transport;
144 	scsi_transport_reserve_device(zfcp_scsi_transport_template,
145 				      sizeof(struct zfcp_scsi_dev));
146 
147 	retval = ccw_driver_register(&zfcp_ccw_driver);
148 	if (retval) {
149 		pr_err("The zfcp device driver could not register with "
150 		       "the common I/O layer\n");
151 		goto out_ccw_register;
152 	}
153 
154 	if (init_device)
155 		zfcp_init_device_setup(init_device);
156 	return 0;
157 
158 out_ccw_register:
159 	fc_release_transport(zfcp_scsi_transport_template);
160 out_transport:
161 	kmem_cache_destroy(zfcp_fc_req_cache);
162 out_fc_cache:
163 	kmem_cache_destroy(zfcp_fsf_qtcb_cache);
164 out_qtcb_cache:
165 	return retval;
166 }
167 
168 module_init(zfcp_module_init);
169 
170 static void __exit zfcp_module_exit(void)
171 {
172 	ccw_driver_unregister(&zfcp_ccw_driver);
173 	fc_release_transport(zfcp_scsi_transport_template);
174 	kmem_cache_destroy(zfcp_fc_req_cache);
175 	kmem_cache_destroy(zfcp_fsf_qtcb_cache);
176 }
177 
178 module_exit(zfcp_module_exit);
179 
180 /**
181  * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
182  * @adapter: pointer to adapter to search for port
183  * @wwpn: wwpn to search for
184  *
185  * Returns: pointer to zfcp_port or NULL
186  */
187 struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
188 					u64 wwpn)
189 {
190 	unsigned long flags;
191 	struct zfcp_port *port;
192 
193 	read_lock_irqsave(&adapter->port_list_lock, flags);
194 	list_for_each_entry(port, &adapter->port_list, list)
195 		if (port->wwpn == wwpn) {
196 			if (!get_device(&port->dev))
197 				port = NULL;
198 			read_unlock_irqrestore(&adapter->port_list_lock, flags);
199 			return port;
200 		}
201 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
202 	return NULL;
203 }
204 
205 static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
206 {
207 	adapter->pool.erp_req =
208 		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
209 	if (!adapter->pool.erp_req)
210 		return -ENOMEM;
211 
212 	adapter->pool.gid_pn_req =
213 		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
214 	if (!adapter->pool.gid_pn_req)
215 		return -ENOMEM;
216 
217 	adapter->pool.scsi_req =
218 		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
219 	if (!adapter->pool.scsi_req)
220 		return -ENOMEM;
221 
222 	adapter->pool.scsi_abort =
223 		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
224 	if (!adapter->pool.scsi_abort)
225 		return -ENOMEM;
226 
227 	adapter->pool.status_read_req =
228 		mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
229 					    sizeof(struct zfcp_fsf_req));
230 	if (!adapter->pool.status_read_req)
231 		return -ENOMEM;
232 
233 	adapter->pool.qtcb_pool =
234 		mempool_create_slab_pool(4, zfcp_fsf_qtcb_cache);
235 	if (!adapter->pool.qtcb_pool)
236 		return -ENOMEM;
237 
238 	BUILD_BUG_ON(sizeof(struct fsf_status_read_buffer) > PAGE_SIZE);
239 	adapter->pool.sr_data =
240 		mempool_create_page_pool(FSF_STATUS_READS_RECOM, 0);
241 	if (!adapter->pool.sr_data)
242 		return -ENOMEM;
243 
244 	adapter->pool.gid_pn =
245 		mempool_create_slab_pool(1, zfcp_fc_req_cache);
246 	if (!adapter->pool.gid_pn)
247 		return -ENOMEM;
248 
249 	return 0;
250 }
251 
252 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
253 {
254 	mempool_destroy(adapter->pool.erp_req);
255 	mempool_destroy(adapter->pool.scsi_req);
256 	mempool_destroy(adapter->pool.scsi_abort);
257 	mempool_destroy(adapter->pool.qtcb_pool);
258 	mempool_destroy(adapter->pool.status_read_req);
259 	mempool_destroy(adapter->pool.sr_data);
260 	mempool_destroy(adapter->pool.gid_pn);
261 }
262 
263 /**
264  * zfcp_status_read_refill - refill the long running status_read_requests
265  * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
266  *
267  * Return:
268  * * 0 on success meaning at least one status read is pending
269  * * 1 if posting failed and not a single status read buffer is pending,
270  *     also triggers adapter reopen recovery
271  */
272 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
273 {
274 	while (atomic_add_unless(&adapter->stat_miss, -1, 0))
275 		if (zfcp_fsf_status_read(adapter->qdio)) {
276 			atomic_inc(&adapter->stat_miss); /* undo add -1 */
277 			if (atomic_read(&adapter->stat_miss) >=
278 			    adapter->stat_read_buf_num) {
279 				zfcp_erp_adapter_reopen(adapter, 0, "axsref1");
280 				return 1;
281 			}
282 			break;
283 		}
284 	return 0;
285 }
286 
287 static void _zfcp_status_read_scheduler(struct work_struct *work)
288 {
289 	zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
290 					     stat_work));
291 }
292 
293 static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
294 {
295 	struct zfcp_adapter *adapter =
296 		container_of(sl, struct zfcp_adapter, service_level);
297 
298 	seq_printf(m, "zfcp: %s microcode level %x\n",
299 		   dev_name(&adapter->ccw_device->dev),
300 		   adapter->fsf_lic_version);
301 }
302 
303 static int zfcp_setup_adapter_work_queue(struct zfcp_adapter *adapter)
304 {
305 	char name[TASK_COMM_LEN];
306 
307 	snprintf(name, sizeof(name), "zfcp_q_%s",
308 		 dev_name(&adapter->ccw_device->dev));
309 	adapter->work_queue = alloc_ordered_workqueue(name, WQ_MEM_RECLAIM);
310 
311 	if (adapter->work_queue)
312 		return 0;
313 	return -ENOMEM;
314 }
315 
316 static void zfcp_destroy_adapter_work_queue(struct zfcp_adapter *adapter)
317 {
318 	if (adapter->work_queue)
319 		destroy_workqueue(adapter->work_queue);
320 	adapter->work_queue = NULL;
321 
322 }
323 
324 /**
325  * zfcp_adapter_enqueue - enqueue a new adapter to the list
326  * @ccw_device: pointer to the struct cc_device
327  *
328  * Returns:	struct zfcp_adapter*
329  * Enqueues an adapter at the end of the adapter list in the driver data.
330  * All adapter internal structures are set up.
331  * Proc-fs entries are also created.
332  */
333 struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
334 {
335 	struct zfcp_adapter *adapter;
336 
337 	if (!get_device(&ccw_device->dev))
338 		return ERR_PTR(-ENODEV);
339 
340 	adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
341 	if (!adapter) {
342 		put_device(&ccw_device->dev);
343 		return ERR_PTR(-ENOMEM);
344 	}
345 
346 	kref_init(&adapter->ref);
347 
348 	ccw_device->handler = NULL;
349 	adapter->ccw_device = ccw_device;
350 
351 	INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
352 	INIT_DELAYED_WORK(&adapter->scan_work, zfcp_fc_scan_ports);
353 	INIT_WORK(&adapter->ns_up_work, zfcp_fc_sym_name_update);
354 
355 	adapter->next_port_scan = jiffies;
356 
357 	adapter->erp_action.adapter = adapter;
358 
359 	if (zfcp_qdio_setup(adapter))
360 		goto failed;
361 
362 	if (zfcp_allocate_low_mem_buffers(adapter))
363 		goto failed;
364 
365 	adapter->req_list = zfcp_reqlist_alloc();
366 	if (!adapter->req_list)
367 		goto failed;
368 
369 	if (zfcp_dbf_adapter_register(adapter))
370 		goto failed;
371 
372 	if (zfcp_setup_adapter_work_queue(adapter))
373 		goto failed;
374 
375 	if (zfcp_fc_gs_setup(adapter))
376 		goto failed;
377 
378 	rwlock_init(&adapter->port_list_lock);
379 	INIT_LIST_HEAD(&adapter->port_list);
380 
381 	INIT_LIST_HEAD(&adapter->events.list);
382 	INIT_WORK(&adapter->events.work, zfcp_fc_post_event);
383 	spin_lock_init(&adapter->events.list_lock);
384 
385 	init_waitqueue_head(&adapter->erp_ready_wq);
386 	init_waitqueue_head(&adapter->erp_done_wqh);
387 
388 	INIT_LIST_HEAD(&adapter->erp_ready_head);
389 	INIT_LIST_HEAD(&adapter->erp_running_head);
390 
391 	rwlock_init(&adapter->erp_lock);
392 	rwlock_init(&adapter->abort_lock);
393 
394 	if (zfcp_erp_thread_setup(adapter))
395 		goto failed;
396 
397 	adapter->service_level.seq_print = zfcp_print_sl;
398 
399 	dev_set_drvdata(&ccw_device->dev, adapter);
400 
401 	if (sysfs_create_group(&ccw_device->dev.kobj,
402 			       &zfcp_sysfs_adapter_attrs))
403 		goto failed;
404 
405 	/* report size limit per scatter-gather segment */
406 	adapter->dma_parms.max_segment_size = ZFCP_QDIO_SBALE_LEN;
407 	adapter->ccw_device->dev.dma_parms = &adapter->dma_parms;
408 
409 	adapter->stat_read_buf_num = FSF_STATUS_READS_RECOM;
410 
411 	if (!zfcp_scsi_adapter_register(adapter))
412 		return adapter;
413 
414 failed:
415 	zfcp_adapter_unregister(adapter);
416 	return ERR_PTR(-ENOMEM);
417 }
418 
419 void zfcp_adapter_unregister(struct zfcp_adapter *adapter)
420 {
421 	struct ccw_device *cdev = adapter->ccw_device;
422 
423 	cancel_delayed_work_sync(&adapter->scan_work);
424 	cancel_work_sync(&adapter->stat_work);
425 	cancel_work_sync(&adapter->ns_up_work);
426 	zfcp_destroy_adapter_work_queue(adapter);
427 
428 	zfcp_fc_wka_ports_force_offline(adapter->gs);
429 	zfcp_scsi_adapter_unregister(adapter);
430 	sysfs_remove_group(&cdev->dev.kobj, &zfcp_sysfs_adapter_attrs);
431 
432 	zfcp_erp_thread_kill(adapter);
433 	zfcp_dbf_adapter_unregister(adapter);
434 	zfcp_qdio_destroy(adapter->qdio);
435 
436 	zfcp_ccw_adapter_put(adapter); /* final put to release */
437 }
438 
439 /**
440  * zfcp_adapter_release - remove the adapter from the resource list
441  * @ref: pointer to struct kref
442  * locks:	adapter list write lock is assumed to be held by caller
443  */
444 void zfcp_adapter_release(struct kref *ref)
445 {
446 	struct zfcp_adapter *adapter = container_of(ref, struct zfcp_adapter,
447 						    ref);
448 	struct ccw_device *cdev = adapter->ccw_device;
449 
450 	dev_set_drvdata(&adapter->ccw_device->dev, NULL);
451 	zfcp_fc_gs_destroy(adapter);
452 	zfcp_free_low_mem_buffers(adapter);
453 	kfree(adapter->req_list);
454 	kfree(adapter->fc_stats);
455 	kfree(adapter->stats_reset_data);
456 	kfree(adapter);
457 	put_device(&cdev->dev);
458 }
459 
460 static void zfcp_port_release(struct device *dev)
461 {
462 	struct zfcp_port *port = container_of(dev, struct zfcp_port, dev);
463 
464 	zfcp_ccw_adapter_put(port->adapter);
465 	kfree(port);
466 }
467 
468 /**
469  * zfcp_port_enqueue - enqueue port to port list of adapter
470  * @adapter: adapter where remote port is added
471  * @wwpn: WWPN of the remote port to be enqueued
472  * @status: initial status for the port
473  * @d_id: destination id of the remote port to be enqueued
474  * Returns: pointer to enqueued port on success, ERR_PTR on error
475  *
476  * All port internal structures are set up and the sysfs entry is generated.
477  * d_id is used to enqueue ports with a well known address like the Directory
478  * Service for nameserver lookup.
479  */
480 struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
481 				     u32 status, u32 d_id)
482 {
483 	struct zfcp_port *port;
484 	int retval = -ENOMEM;
485 
486 	kref_get(&adapter->ref);
487 
488 	port = zfcp_get_port_by_wwpn(adapter, wwpn);
489 	if (port) {
490 		put_device(&port->dev);
491 		retval = -EEXIST;
492 		goto err_out;
493 	}
494 
495 	port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
496 	if (!port)
497 		goto err_out;
498 
499 	rwlock_init(&port->unit_list_lock);
500 	INIT_LIST_HEAD(&port->unit_list);
501 	atomic_set(&port->units, 0);
502 
503 	INIT_WORK(&port->gid_pn_work, zfcp_fc_port_did_lookup);
504 	INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
505 	INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
506 
507 	port->adapter = adapter;
508 	port->d_id = d_id;
509 	port->wwpn = wwpn;
510 	port->rport_task = RPORT_NONE;
511 	port->dev.parent = &adapter->ccw_device->dev;
512 	port->dev.groups = zfcp_port_attr_groups;
513 	port->dev.release = zfcp_port_release;
514 
515 	port->erp_action.adapter = adapter;
516 	port->erp_action.port = port;
517 
518 	if (dev_set_name(&port->dev, "0x%016llx", (unsigned long long)wwpn)) {
519 		kfree(port);
520 		goto err_out;
521 	}
522 	retval = -EINVAL;
523 
524 	if (device_register(&port->dev)) {
525 		put_device(&port->dev);
526 		goto err_out;
527 	}
528 
529 	write_lock_irq(&adapter->port_list_lock);
530 	list_add_tail(&port->list, &adapter->port_list);
531 	write_unlock_irq(&adapter->port_list_lock);
532 
533 	atomic_or(status | ZFCP_STATUS_COMMON_RUNNING, &port->status);
534 
535 	return port;
536 
537 err_out:
538 	zfcp_ccw_adapter_put(adapter);
539 	return ERR_PTR(retval);
540 }
541