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
44MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
45MODULE_DESCRIPTION("FCP HBA driver");
46MODULE_LICENSE("GPL");
47
48static char *init_device;
49module_param_named(device, init_device, charp, 0400);
50MODULE_PARM_DESC(device, "specify initial device");
51
52static 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
58static 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
83out_port:
84	zfcp_ccw_adapter_put(adapter);
85out_ccw_device:
86	put_device(&cdev->dev);
87	return;
88}
89
90static 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
120err_out:
121	kfree(str_saved);
122	pr_err("%s is not a valid SCSI device\n", devstr);
123}
124
125static 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
160out_ccw_register:
161	fc_release_transport(zfcp_scsi_transport_template);
162out_transport:
163	kmem_cache_destroy(zfcp_fc_req_cache);
164out_fc_cache:
165	kmem_cache_destroy(zfcp_fsf_qtcb_cache);
166out_qtcb_cache:
167	return retval;
168}
169
170module_init(zfcp_module_init);
171
172static 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
180module_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 */
189struct 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
207static 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
254static 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 */
274int 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
289static 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
295static 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
303static 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
313static int zfcp_setup_adapter_work_queue(struct zfcp_adapter *adapter)
314{
315	char name[TASK_COMM_LEN];
316
317	snprintf(name, sizeof(name), "zfcp_q_%s",
318		 dev_name(&adapter->ccw_device->dev));
319	adapter->work_queue = alloc_ordered_workqueue(name, WQ_MEM_RECLAIM);
320
321	if (adapter->work_queue)
322		return 0;
323	return -ENOMEM;
324}
325
326static void zfcp_destroy_adapter_work_queue(struct zfcp_adapter *adapter)
327{
328	if (adapter->work_queue)
329		destroy_workqueue(adapter->work_queue);
330	adapter->work_queue = NULL;
331
332}
333
334/**
335 * zfcp_adapter_enqueue - enqueue a new adapter to the list
336 * @ccw_device: pointer to the struct cc_device
337 *
338 * Returns:	struct zfcp_adapter*
339 * Enqueues an adapter at the end of the adapter list in the driver data.
340 * All adapter internal structures are set up.
341 * Proc-fs entries are also created.
342 */
343struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
344{
345	struct zfcp_adapter *adapter;
346
347	if (!get_device(&ccw_device->dev))
348		return ERR_PTR(-ENODEV);
349
350	adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
351	if (!adapter) {
352		put_device(&ccw_device->dev);
353		return ERR_PTR(-ENOMEM);
354	}
355
356	kref_init(&adapter->ref);
357
358	ccw_device->handler = NULL;
359	adapter->ccw_device = ccw_device;
360
361	INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
362	INIT_DELAYED_WORK(&adapter->scan_work, zfcp_fc_scan_ports);
363	INIT_WORK(&adapter->ns_up_work, zfcp_fc_sym_name_update);
364	INIT_WORK(&adapter->version_change_lost_work,
365		  zfcp_version_change_lost_work);
366
367	adapter->next_port_scan = jiffies;
368
369	adapter->erp_action.adapter = adapter;
370
371	if (zfcp_diag_adapter_setup(adapter))
372		goto failed;
373
374	if (zfcp_qdio_setup(adapter))
375		goto failed;
376
377	if (zfcp_allocate_low_mem_buffers(adapter))
378		goto failed;
379
380	adapter->req_list = zfcp_reqlist_alloc();
381	if (!adapter->req_list)
382		goto failed;
383
384	if (zfcp_dbf_adapter_register(adapter))
385		goto failed;
386
387	if (zfcp_setup_adapter_work_queue(adapter))
388		goto failed;
389
390	if (zfcp_fc_gs_setup(adapter))
391		goto failed;
392
393	rwlock_init(&adapter->port_list_lock);
394	INIT_LIST_HEAD(&adapter->port_list);
395
396	INIT_LIST_HEAD(&adapter->events.list);
397	INIT_WORK(&adapter->events.work, zfcp_fc_post_event);
398	spin_lock_init(&adapter->events.list_lock);
399
400	init_waitqueue_head(&adapter->erp_ready_wq);
401	init_waitqueue_head(&adapter->erp_done_wqh);
402
403	INIT_LIST_HEAD(&adapter->erp_ready_head);
404	INIT_LIST_HEAD(&adapter->erp_running_head);
405
406	rwlock_init(&adapter->erp_lock);
407	rwlock_init(&adapter->abort_lock);
408
409	if (zfcp_erp_thread_setup(adapter))
410		goto failed;
411
412	adapter->service_level.seq_print = zfcp_print_sl;
413
414	dev_set_drvdata(&ccw_device->dev, adapter);
415
416	if (device_add_groups(&ccw_device->dev, zfcp_sysfs_adapter_attr_groups))
417		goto err_sysfs;
418
419	/* report size limit per scatter-gather segment */
420	adapter->ccw_device->dev.dma_parms = &adapter->dma_parms;
421
422	adapter->stat_read_buf_num = FSF_STATUS_READS_RECOM;
423
424	return adapter;
425
426err_sysfs:
427failed:
428	/* TODO: make this more fine-granular */
429	cancel_delayed_work_sync(&adapter->scan_work);
430	cancel_work_sync(&adapter->stat_work);
431	cancel_work_sync(&adapter->ns_up_work);
432	cancel_work_sync(&adapter->version_change_lost_work);
433	zfcp_destroy_adapter_work_queue(adapter);
434
435	zfcp_fc_wka_ports_force_offline(adapter->gs);
436	zfcp_scsi_adapter_unregister(adapter);
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	return ERR_PTR(-ENOMEM);
444}
445
446void zfcp_adapter_unregister(struct zfcp_adapter *adapter)
447{
448	struct ccw_device *cdev = adapter->ccw_device;
449
450	cancel_delayed_work_sync(&adapter->scan_work);
451	cancel_work_sync(&adapter->stat_work);
452	cancel_work_sync(&adapter->ns_up_work);
453	cancel_work_sync(&adapter->version_change_lost_work);
454	zfcp_destroy_adapter_work_queue(adapter);
455
456	zfcp_fc_wka_ports_force_offline(adapter->gs);
457	zfcp_scsi_adapter_unregister(adapter);
458	device_remove_groups(&cdev->dev, zfcp_sysfs_adapter_attr_groups);
459
460	zfcp_erp_thread_kill(adapter);
461	zfcp_dbf_adapter_unregister(adapter);
462	zfcp_qdio_destroy(adapter->qdio);
463
464	zfcp_ccw_adapter_put(adapter); /* final put to release */
465}
466
467/**
468 * zfcp_adapter_release - remove the adapter from the resource list
469 * @ref: pointer to struct kref
470 * locks:	adapter list write lock is assumed to be held by caller
471 */
472void zfcp_adapter_release(struct kref *ref)
473{
474	struct zfcp_adapter *adapter = container_of(ref, struct zfcp_adapter,
475						    ref);
476	struct ccw_device *cdev = adapter->ccw_device;
477
478	dev_set_drvdata(&adapter->ccw_device->dev, NULL);
479	zfcp_fc_gs_destroy(adapter);
480	zfcp_free_low_mem_buffers(adapter);
481	zfcp_diag_adapter_free(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
489static void zfcp_port_release(struct device *dev)
490{
491	struct zfcp_port *port = container_of(dev, struct zfcp_port, dev);
492
493	zfcp_ccw_adapter_put(port->adapter);
494	kfree(port);
495}
496
497/**
498 * zfcp_port_enqueue - enqueue port to port list of adapter
499 * @adapter: adapter where remote port is added
500 * @wwpn: WWPN of the remote port to be enqueued
501 * @status: initial status for the port
502 * @d_id: destination id of the remote port to be enqueued
503 * Returns: pointer to enqueued port on success, ERR_PTR on error
504 *
505 * All port internal structures are set up and the sysfs entry is generated.
506 * d_id is used to enqueue ports with a well known address like the Directory
507 * Service for nameserver lookup.
508 */
509struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
510				     u32 status, u32 d_id)
511{
512	struct zfcp_port *port;
513	int retval = -ENOMEM;
514
515	kref_get(&adapter->ref);
516
517	port = zfcp_get_port_by_wwpn(adapter, wwpn);
518	if (port) {
519		put_device(&port->dev);
520		retval = -EEXIST;
521		goto err_put;
522	}
523
524	port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
525	if (!port)
526		goto err_put;
527
528	rwlock_init(&port->unit_list_lock);
529	INIT_LIST_HEAD(&port->unit_list);
530	atomic_set(&port->units, 0);
531
532	INIT_WORK(&port->gid_pn_work, zfcp_fc_port_did_lookup);
533	INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
534	INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
535
536	port->adapter = adapter;
537	port->d_id = d_id;
538	port->wwpn = wwpn;
539	port->rport_task = RPORT_NONE;
540	port->dev.parent = &adapter->ccw_device->dev;
541	port->dev.groups = zfcp_port_attr_groups;
542	port->dev.release = zfcp_port_release;
543
544	port->erp_action.adapter = adapter;
545	port->erp_action.port = port;
546
547	if (dev_set_name(&port->dev, "0x%016llx", (unsigned long long)wwpn)) {
548		kfree(port);
549		goto err_put;
550	}
551	retval = -EINVAL;
552
553	if (device_register(&port->dev)) {
554		put_device(&port->dev);
555		goto err_out;
556	}
557
558	write_lock_irq(&adapter->port_list_lock);
559	list_add_tail(&port->list, &adapter->port_list);
560	write_unlock_irq(&adapter->port_list_lock);
561
562	atomic_or(status | ZFCP_STATUS_COMMON_RUNNING, &port->status);
563
564	return port;
565
566err_put:
567	zfcp_ccw_adapter_put(adapter);
568err_out:
569	return ERR_PTR(retval);
570}
571