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, 2020
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  *	      Benjamin Block
29  */
30 
31 #define KMSG_COMPONENT "zfcp"
32 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
33 
34 #include <linux/seq_file.h>
35 #include <linux/slab.h>
36 #include <linux/module.h>
37 #include "zfcp_ext.h"
38 #include "zfcp_fc.h"
39 #include "zfcp_reqlist.h"
40 #include "zfcp_diag.h"
41 
42 #define ZFCP_BUS_ID_SIZE	20
43 
44 MODULE_AUTHOR("IBM Corporation");
45 MODULE_DESCRIPTION("FCP HBA driver");
46 MODULE_LICENSE("GPL");
47 
48 static char *init_device;
49 module_param_named(device, init_device, charp, 0400);
50 MODULE_PARM_DESC(device, "specify initial device");
51 
52 static struct kmem_cache * __init zfcp_cache_hw_align(const char *name,
53 						      unsigned long size)
54 {
55 	return kmem_cache_create(name, size, roundup_pow_of_two(size), 0, NULL);
56 }
57 
58 static void __init zfcp_init_device_configure(char *busid, u64 wwpn, u64 lun)
59 {
60 	struct ccw_device *cdev;
61 	struct zfcp_adapter *adapter;
62 	struct zfcp_port *port;
63 
64 	cdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
65 	if (!cdev)
66 		return;
67 
68 	if (ccw_device_set_online(cdev))
69 		goto out_ccw_device;
70 
71 	adapter = zfcp_ccw_adapter_by_cdev(cdev);
72 	if (!adapter)
73 		goto out_ccw_device;
74 
75 	port = zfcp_get_port_by_wwpn(adapter, wwpn);
76 	if (!port)
77 		goto out_port;
78 	flush_work(&port->rport_work);
79 
80 	zfcp_unit_add(port, lun);
81 	put_device(&port->dev);
82 
83 out_port:
84 	zfcp_ccw_adapter_put(adapter);
85 out_ccw_device:
86 	put_device(&cdev->dev);
87 	return;
88 }
89 
90 static void __init zfcp_init_device_setup(char *devstr)
91 {
92 	char *token;
93 	char *str, *str_saved;
94 	char busid[ZFCP_BUS_ID_SIZE];
95 	u64 wwpn, lun;
96 
97 	/* duplicate devstr and keep the original for sysfs presentation*/
98 	str_saved = kstrdup(devstr, GFP_KERNEL);
99 	str = str_saved;
100 	if (!str)
101 		return;
102 
103 	token = strsep(&str, ",");
104 	if (!token || strlen(token) >= ZFCP_BUS_ID_SIZE)
105 		goto err_out;
106 	strscpy(busid, token, ZFCP_BUS_ID_SIZE);
107 
108 	token = strsep(&str, ",");
109 	if (!token || kstrtoull(token, 0, (unsigned long long *) &wwpn))
110 		goto err_out;
111 
112 	token = strsep(&str, ",");
113 	if (!token || kstrtoull(token, 0, (unsigned long long *) &lun))
114 		goto err_out;
115 
116 	kfree(str_saved);
117 	zfcp_init_device_configure(busid, wwpn, lun);
118 	return;
119 
120 err_out:
121 	kfree(str_saved);
122 	pr_err("%s is not a valid SCSI device\n", devstr);
123 }
124 
125 static int __init zfcp_module_init(void)
126 {
127 	int retval = -ENOMEM;
128 
129 	if (zfcp_experimental_dix)
130 		pr_warn("DIX is enabled. It is experimental and might cause problems\n");
131 
132 	zfcp_fsf_qtcb_cache = zfcp_cache_hw_align("zfcp_fsf_qtcb",
133 						  sizeof(struct fsf_qtcb));
134 	if (!zfcp_fsf_qtcb_cache)
135 		goto out_qtcb_cache;
136 
137 	zfcp_fc_req_cache = zfcp_cache_hw_align("zfcp_fc_req",
138 						sizeof(struct zfcp_fc_req));
139 	if (!zfcp_fc_req_cache)
140 		goto out_fc_cache;
141 
142 	zfcp_scsi_transport_template =
143 		fc_attach_transport(&zfcp_transport_functions);
144 	if (!zfcp_scsi_transport_template)
145 		goto out_transport;
146 	scsi_transport_reserve_device(zfcp_scsi_transport_template,
147 				      sizeof(struct zfcp_scsi_dev));
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 	fc_release_transport(zfcp_scsi_transport_template);
162 out_transport:
163 	kmem_cache_destroy(zfcp_fc_req_cache);
164 out_fc_cache:
165 	kmem_cache_destroy(zfcp_fsf_qtcb_cache);
166 out_qtcb_cache:
167 	return retval;
168 }
169 
170 module_init(zfcp_module_init);
171 
172 static void __exit zfcp_module_exit(void)
173 {
174 	ccw_driver_unregister(&zfcp_ccw_driver);
175 	fc_release_transport(zfcp_scsi_transport_template);
176 	kmem_cache_destroy(zfcp_fc_req_cache);
177 	kmem_cache_destroy(zfcp_fsf_qtcb_cache);
178 }
179 
180 module_exit(zfcp_module_exit);
181 
182 /**
183  * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
184  * @adapter: pointer to adapter to search for port
185  * @wwpn: wwpn to search for
186  *
187  * Returns: pointer to zfcp_port or NULL
188  */
189 struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
190 					u64 wwpn)
191 {
192 	unsigned long flags;
193 	struct zfcp_port *port;
194 
195 	read_lock_irqsave(&adapter->port_list_lock, flags);
196 	list_for_each_entry(port, &adapter->port_list, list)
197 		if (port->wwpn == wwpn) {
198 			if (!get_device(&port->dev))
199 				port = NULL;
200 			read_unlock_irqrestore(&adapter->port_list_lock, flags);
201 			return port;
202 		}
203 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
204 	return NULL;
205 }
206 
207 static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
208 {
209 	adapter->pool.erp_req =
210 		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
211 	if (!adapter->pool.erp_req)
212 		return -ENOMEM;
213 
214 	adapter->pool.gid_pn_req =
215 		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
216 	if (!adapter->pool.gid_pn_req)
217 		return -ENOMEM;
218 
219 	adapter->pool.scsi_req =
220 		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
221 	if (!adapter->pool.scsi_req)
222 		return -ENOMEM;
223 
224 	adapter->pool.scsi_abort =
225 		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
226 	if (!adapter->pool.scsi_abort)
227 		return -ENOMEM;
228 
229 	adapter->pool.status_read_req =
230 		mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
231 					    sizeof(struct zfcp_fsf_req));
232 	if (!adapter->pool.status_read_req)
233 		return -ENOMEM;
234 
235 	adapter->pool.qtcb_pool =
236 		mempool_create_slab_pool(4, zfcp_fsf_qtcb_cache);
237 	if (!adapter->pool.qtcb_pool)
238 		return -ENOMEM;
239 
240 	BUILD_BUG_ON(sizeof(struct fsf_status_read_buffer) > PAGE_SIZE);
241 	adapter->pool.sr_data =
242 		mempool_create_page_pool(FSF_STATUS_READS_RECOM, 0);
243 	if (!adapter->pool.sr_data)
244 		return -ENOMEM;
245 
246 	adapter->pool.gid_pn =
247 		mempool_create_slab_pool(1, zfcp_fc_req_cache);
248 	if (!adapter->pool.gid_pn)
249 		return -ENOMEM;
250 
251 	return 0;
252 }
253 
254 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
255 {
256 	mempool_destroy(adapter->pool.erp_req);
257 	mempool_destroy(adapter->pool.scsi_req);
258 	mempool_destroy(adapter->pool.scsi_abort);
259 	mempool_destroy(adapter->pool.qtcb_pool);
260 	mempool_destroy(adapter->pool.status_read_req);
261 	mempool_destroy(adapter->pool.sr_data);
262 	mempool_destroy(adapter->pool.gid_pn);
263 }
264 
265 /**
266  * zfcp_status_read_refill - refill the long running status_read_requests
267  * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
268  *
269  * Return:
270  * * 0 on success meaning at least one status read is pending
271  * * 1 if posting failed and not a single status read buffer is pending,
272  *     also triggers adapter reopen recovery
273  */
274 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
275 {
276 	while (atomic_add_unless(&adapter->stat_miss, -1, 0))
277 		if (zfcp_fsf_status_read(adapter->qdio)) {
278 			atomic_inc(&adapter->stat_miss); /* undo add -1 */
279 			if (atomic_read(&adapter->stat_miss) >=
280 			    adapter->stat_read_buf_num) {
281 				zfcp_erp_adapter_reopen(adapter, 0, "axsref1");
282 				return 1;
283 			}
284 			break;
285 		}
286 	return 0;
287 }
288 
289 static void _zfcp_status_read_scheduler(struct work_struct *work)
290 {
291 	zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
292 					     stat_work));
293 }
294 
295 static void zfcp_version_change_lost_work(struct work_struct *work)
296 {
297 	struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
298 						    version_change_lost_work);
299 
300 	zfcp_fsf_exchange_config_data_sync(adapter->qdio, NULL);
301 }
302 
303 static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
304 {
305 	struct zfcp_adapter *adapter =
306 		container_of(sl, struct zfcp_adapter, service_level);
307 
308 	seq_printf(m, "zfcp: %s microcode level %x\n",
309 		   dev_name(&adapter->ccw_device->dev),
310 		   adapter->fsf_lic_version);
311 }
312 
313 static int zfcp_setup_adapter_work_queue(struct zfcp_adapter *adapter)
314 {
315 	adapter->work_queue =
316 		alloc_ordered_workqueue("zfcp_q_%s", WQ_MEM_RECLAIM,
317 					dev_name(&adapter->ccw_device->dev));
318 	if (!adapter->work_queue)
319 		return -ENOMEM;
320 
321 	return 0;
322 }
323 
324 static void zfcp_destroy_adapter_work_queue(struct zfcp_adapter *adapter)
325 {
326 	if (adapter->work_queue)
327 		destroy_workqueue(adapter->work_queue);
328 	adapter->work_queue = NULL;
329 
330 }
331 
332 /**
333  * zfcp_adapter_enqueue - enqueue a new adapter to the list
334  * @ccw_device: pointer to the struct cc_device
335  *
336  * Returns:	struct zfcp_adapter*
337  * Enqueues an adapter at the end of the adapter list in the driver data.
338  * All adapter internal structures are set up.
339  * Proc-fs entries are also created.
340  */
341 struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
342 {
343 	struct zfcp_adapter *adapter;
344 
345 	if (!get_device(&ccw_device->dev))
346 		return ERR_PTR(-ENODEV);
347 
348 	adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
349 	if (!adapter) {
350 		put_device(&ccw_device->dev);
351 		return ERR_PTR(-ENOMEM);
352 	}
353 
354 	kref_init(&adapter->ref);
355 
356 	ccw_device->handler = NULL;
357 	adapter->ccw_device = ccw_device;
358 
359 	INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
360 	INIT_DELAYED_WORK(&adapter->scan_work, zfcp_fc_scan_ports);
361 	INIT_WORK(&adapter->ns_up_work, zfcp_fc_sym_name_update);
362 	INIT_WORK(&adapter->version_change_lost_work,
363 		  zfcp_version_change_lost_work);
364 
365 	adapter->next_port_scan = jiffies;
366 
367 	adapter->erp_action.adapter = adapter;
368 
369 	if (zfcp_diag_adapter_setup(adapter))
370 		goto failed;
371 
372 	if (zfcp_qdio_setup(adapter))
373 		goto failed;
374 
375 	if (zfcp_allocate_low_mem_buffers(adapter))
376 		goto failed;
377 
378 	adapter->req_list = zfcp_reqlist_alloc();
379 	if (!adapter->req_list)
380 		goto failed;
381 
382 	if (zfcp_dbf_adapter_register(adapter))
383 		goto failed;
384 
385 	if (zfcp_setup_adapter_work_queue(adapter))
386 		goto failed;
387 
388 	if (zfcp_fc_gs_setup(adapter))
389 		goto failed;
390 
391 	rwlock_init(&adapter->port_list_lock);
392 	INIT_LIST_HEAD(&adapter->port_list);
393 
394 	INIT_LIST_HEAD(&adapter->events.list);
395 	INIT_WORK(&adapter->events.work, zfcp_fc_post_event);
396 	spin_lock_init(&adapter->events.list_lock);
397 
398 	init_waitqueue_head(&adapter->erp_ready_wq);
399 	init_waitqueue_head(&adapter->erp_done_wqh);
400 
401 	INIT_LIST_HEAD(&adapter->erp_ready_head);
402 	INIT_LIST_HEAD(&adapter->erp_running_head);
403 
404 	rwlock_init(&adapter->erp_lock);
405 	rwlock_init(&adapter->abort_lock);
406 
407 	if (zfcp_erp_thread_setup(adapter))
408 		goto failed;
409 
410 	adapter->service_level.seq_print = zfcp_print_sl;
411 
412 	dev_set_drvdata(&ccw_device->dev, adapter);
413 
414 	if (device_add_groups(&ccw_device->dev, zfcp_sysfs_adapter_attr_groups))
415 		goto err_sysfs;
416 
417 	/* report size limit per scatter-gather segment */
418 	adapter->ccw_device->dev.dma_parms = &adapter->dma_parms;
419 
420 	adapter->stat_read_buf_num = FSF_STATUS_READS_RECOM;
421 
422 	return adapter;
423 
424 err_sysfs:
425 failed:
426 	/* TODO: make this more fine-granular */
427 	cancel_delayed_work_sync(&adapter->scan_work);
428 	cancel_work_sync(&adapter->stat_work);
429 	cancel_work_sync(&adapter->ns_up_work);
430 	cancel_work_sync(&adapter->version_change_lost_work);
431 	zfcp_destroy_adapter_work_queue(adapter);
432 
433 	zfcp_fc_wka_ports_force_offline(adapter->gs);
434 	zfcp_scsi_adapter_unregister(adapter);
435 
436 	zfcp_erp_thread_kill(adapter);
437 	zfcp_dbf_adapter_unregister(adapter);
438 	zfcp_qdio_destroy(adapter->qdio);
439 
440 	zfcp_ccw_adapter_put(adapter); /* final put to release */
441 	return ERR_PTR(-ENOMEM);
442 }
443 
444 void zfcp_adapter_unregister(struct zfcp_adapter *adapter)
445 {
446 	struct ccw_device *cdev = adapter->ccw_device;
447 
448 	cancel_delayed_work_sync(&adapter->scan_work);
449 	cancel_work_sync(&adapter->stat_work);
450 	cancel_work_sync(&adapter->ns_up_work);
451 	cancel_work_sync(&adapter->version_change_lost_work);
452 	zfcp_destroy_adapter_work_queue(adapter);
453 
454 	zfcp_fc_wka_ports_force_offline(adapter->gs);
455 	zfcp_scsi_adapter_unregister(adapter);
456 	device_remove_groups(&cdev->dev, zfcp_sysfs_adapter_attr_groups);
457 
458 	zfcp_erp_thread_kill(adapter);
459 	zfcp_dbf_adapter_unregister(adapter);
460 	zfcp_qdio_destroy(adapter->qdio);
461 
462 	zfcp_ccw_adapter_put(adapter); /* final put to release */
463 }
464 
465 /**
466  * zfcp_adapter_release - remove the adapter from the resource list
467  * @ref: pointer to struct kref
468  * locks:	adapter list write lock is assumed to be held by caller
469  */
470 void zfcp_adapter_release(struct kref *ref)
471 {
472 	struct zfcp_adapter *adapter = container_of(ref, struct zfcp_adapter,
473 						    ref);
474 	struct ccw_device *cdev = adapter->ccw_device;
475 
476 	dev_set_drvdata(&adapter->ccw_device->dev, NULL);
477 	zfcp_fc_gs_destroy(adapter);
478 	zfcp_free_low_mem_buffers(adapter);
479 	zfcp_diag_adapter_free(adapter);
480 	kfree(adapter->req_list);
481 	kfree(adapter->fc_stats);
482 	kfree(adapter->stats_reset_data);
483 	kfree(adapter);
484 	put_device(&cdev->dev);
485 }
486 
487 static void zfcp_port_release(struct device *dev)
488 {
489 	struct zfcp_port *port = container_of(dev, struct zfcp_port, dev);
490 
491 	zfcp_ccw_adapter_put(port->adapter);
492 	kfree(port);
493 }
494 
495 /**
496  * zfcp_port_enqueue - enqueue port to port list of adapter
497  * @adapter: adapter where remote port is added
498  * @wwpn: WWPN of the remote port to be enqueued
499  * @status: initial status for the port
500  * @d_id: destination id of the remote port to be enqueued
501  * Returns: pointer to enqueued port on success, ERR_PTR on error
502  *
503  * All port internal structures are set up and the sysfs entry is generated.
504  * d_id is used to enqueue ports with a well known address like the Directory
505  * Service for nameserver lookup.
506  */
507 struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
508 				     u32 status, u32 d_id)
509 {
510 	struct zfcp_port *port;
511 	int retval = -ENOMEM;
512 
513 	kref_get(&adapter->ref);
514 
515 	port = zfcp_get_port_by_wwpn(adapter, wwpn);
516 	if (port) {
517 		put_device(&port->dev);
518 		retval = -EEXIST;
519 		goto err_put;
520 	}
521 
522 	port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
523 	if (!port)
524 		goto err_put;
525 
526 	rwlock_init(&port->unit_list_lock);
527 	INIT_LIST_HEAD(&port->unit_list);
528 	atomic_set(&port->units, 0);
529 
530 	INIT_WORK(&port->gid_pn_work, zfcp_fc_port_did_lookup);
531 	INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
532 	INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
533 
534 	port->adapter = adapter;
535 	port->d_id = d_id;
536 	port->wwpn = wwpn;
537 	port->rport_task = RPORT_NONE;
538 	port->dev.parent = &adapter->ccw_device->dev;
539 	port->dev.groups = zfcp_port_attr_groups;
540 	port->dev.release = zfcp_port_release;
541 
542 	port->erp_action.adapter = adapter;
543 	port->erp_action.port = port;
544 
545 	if (dev_set_name(&port->dev, "0x%016llx", (unsigned long long)wwpn)) {
546 		kfree(port);
547 		goto err_put;
548 	}
549 	retval = -EINVAL;
550 
551 	if (device_register(&port->dev)) {
552 		put_device(&port->dev);
553 		goto err_out;
554 	}
555 
556 	write_lock_irq(&adapter->port_list_lock);
557 	list_add_tail(&port->list, &adapter->port_list);
558 	write_unlock_irq(&adapter->port_list_lock);
559 
560 	atomic_or(status | ZFCP_STATUS_COMMON_RUNNING, &port->status);
561 
562 	return port;
563 
564 err_put:
565 	zfcp_ccw_adapter_put(adapter);
566 err_out:
567 	return ERR_PTR(retval);
568 }
569