1/*
2 * zfcp device driver
3 *
4 * Module interface and handling of zfcp data structures.
5 *
6 * Copyright IBM Corp. 2002, 2013
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 *            Steffen Maier
27 */
28
29#define KMSG_COMPONENT "zfcp"
30#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
31
32#include <linux/miscdevice.h>
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
42MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
43MODULE_DESCRIPTION("FCP HBA driver");
44MODULE_LICENSE("GPL");
45
46static char *init_device;
47module_param_named(device, init_device, charp, 0400);
48MODULE_PARM_DESC(device, "specify initial device");
49
50static 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
56static 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
81out_port:
82	zfcp_ccw_adapter_put(adapter);
83out_ccw_device:
84	put_device(&cdev->dev);
85	return;
86}
87
88static 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	strncpy(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
118err_out:
119	kfree(str_saved);
120	pr_err("%s is not a valid SCSI device\n", devstr);
121}
122
123static int __init zfcp_module_init(void)
124{
125	int retval = -ENOMEM;
126
127	zfcp_fsf_qtcb_cache = zfcp_cache_hw_align("zfcp_fsf_qtcb",
128						  sizeof(struct fsf_qtcb));
129	if (!zfcp_fsf_qtcb_cache)
130		goto out_qtcb_cache;
131
132	zfcp_fc_req_cache = zfcp_cache_hw_align("zfcp_fc_req",
133						sizeof(struct zfcp_fc_req));
134	if (!zfcp_fc_req_cache)
135		goto out_fc_cache;
136
137	zfcp_scsi_transport_template =
138		fc_attach_transport(&zfcp_transport_functions);
139	if (!zfcp_scsi_transport_template)
140		goto out_transport;
141	scsi_transport_reserve_device(zfcp_scsi_transport_template,
142				      sizeof(struct zfcp_scsi_dev));
143
144	retval = ccw_driver_register(&zfcp_ccw_driver);
145	if (retval) {
146		pr_err("The zfcp device driver could not register with "
147		       "the common I/O layer\n");
148		goto out_ccw_register;
149	}
150
151	if (init_device)
152		zfcp_init_device_setup(init_device);
153	return 0;
154
155out_ccw_register:
156	fc_release_transport(zfcp_scsi_transport_template);
157out_transport:
158	kmem_cache_destroy(zfcp_fc_req_cache);
159out_fc_cache:
160	kmem_cache_destroy(zfcp_fsf_qtcb_cache);
161out_qtcb_cache:
162	return retval;
163}
164
165module_init(zfcp_module_init);
166
167static void __exit zfcp_module_exit(void)
168{
169	ccw_driver_unregister(&zfcp_ccw_driver);
170	fc_release_transport(zfcp_scsi_transport_template);
171	kmem_cache_destroy(zfcp_fc_req_cache);
172	kmem_cache_destroy(zfcp_fsf_qtcb_cache);
173}
174
175module_exit(zfcp_module_exit);
176
177/**
178 * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
179 * @adapter: pointer to adapter to search for port
180 * @wwpn: wwpn to search for
181 *
182 * Returns: pointer to zfcp_port or NULL
183 */
184struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
185					u64 wwpn)
186{
187	unsigned long flags;
188	struct zfcp_port *port;
189
190	read_lock_irqsave(&adapter->port_list_lock, flags);
191	list_for_each_entry(port, &adapter->port_list, list)
192		if (port->wwpn == wwpn) {
193			if (!get_device(&port->dev))
194				port = NULL;
195			read_unlock_irqrestore(&adapter->port_list_lock, flags);
196			return port;
197		}
198	read_unlock_irqrestore(&adapter->port_list_lock, flags);
199	return NULL;
200}
201
202static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
203{
204	adapter->pool.erp_req =
205		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
206	if (!adapter->pool.erp_req)
207		return -ENOMEM;
208
209	adapter->pool.gid_pn_req =
210		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
211	if (!adapter->pool.gid_pn_req)
212		return -ENOMEM;
213
214	adapter->pool.scsi_req =
215		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
216	if (!adapter->pool.scsi_req)
217		return -ENOMEM;
218
219	adapter->pool.scsi_abort =
220		mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
221	if (!adapter->pool.scsi_abort)
222		return -ENOMEM;
223
224	adapter->pool.status_read_req =
225		mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
226					    sizeof(struct zfcp_fsf_req));
227	if (!adapter->pool.status_read_req)
228		return -ENOMEM;
229
230	adapter->pool.qtcb_pool =
231		mempool_create_slab_pool(4, zfcp_fsf_qtcb_cache);
232	if (!adapter->pool.qtcb_pool)
233		return -ENOMEM;
234
235	BUILD_BUG_ON(sizeof(struct fsf_status_read_buffer) > PAGE_SIZE);
236	adapter->pool.sr_data =
237		mempool_create_page_pool(FSF_STATUS_READS_RECOM, 0);
238	if (!adapter->pool.sr_data)
239		return -ENOMEM;
240
241	adapter->pool.gid_pn =
242		mempool_create_slab_pool(1, zfcp_fc_req_cache);
243	if (!adapter->pool.gid_pn)
244		return -ENOMEM;
245
246	return 0;
247}
248
249static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
250{
251	if (adapter->pool.erp_req)
252		mempool_destroy(adapter->pool.erp_req);
253	if (adapter->pool.scsi_req)
254		mempool_destroy(adapter->pool.scsi_req);
255	if (adapter->pool.scsi_abort)
256		mempool_destroy(adapter->pool.scsi_abort);
257	if (adapter->pool.qtcb_pool)
258		mempool_destroy(adapter->pool.qtcb_pool);
259	if (adapter->pool.status_read_req)
260		mempool_destroy(adapter->pool.status_read_req);
261	if (adapter->pool.sr_data)
262		mempool_destroy(adapter->pool.sr_data);
263	if (adapter->pool.gid_pn)
264		mempool_destroy(adapter->pool.gid_pn);
265}
266
267/**
268 * zfcp_status_read_refill - refill the long running status_read_requests
269 * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
270 *
271 * Returns: 0 on success, 1 otherwise
272 *
273 * if there are 16 or more status_read requests missing an adapter_reopen
274 * is triggered
275 */
276int zfcp_status_read_refill(struct zfcp_adapter *adapter)
277{
278	while (atomic_read(&adapter->stat_miss) > 0)
279		if (zfcp_fsf_status_read(adapter->qdio)) {
280			if (atomic_read(&adapter->stat_miss) >=
281			    adapter->stat_read_buf_num) {
282				zfcp_erp_adapter_reopen(adapter, 0, "axsref1");
283				return 1;
284			}
285			break;
286		} else
287			atomic_dec(&adapter->stat_miss);
288	return 0;
289}
290
291static void _zfcp_status_read_scheduler(struct work_struct *work)
292{
293	zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
294					     stat_work));
295}
296
297static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
298{
299	struct zfcp_adapter *adapter =
300		container_of(sl, struct zfcp_adapter, service_level);
301
302	seq_printf(m, "zfcp: %s microcode level %x\n",
303		   dev_name(&adapter->ccw_device->dev),
304		   adapter->fsf_lic_version);
305}
306
307static int zfcp_setup_adapter_work_queue(struct zfcp_adapter *adapter)
308{
309	char name[TASK_COMM_LEN];
310
311	snprintf(name, sizeof(name), "zfcp_q_%s",
312		 dev_name(&adapter->ccw_device->dev));
313	adapter->work_queue = create_singlethread_workqueue(name);
314
315	if (adapter->work_queue)
316		return 0;
317	return -ENOMEM;
318}
319
320static void zfcp_destroy_adapter_work_queue(struct zfcp_adapter *adapter)
321{
322	if (adapter->work_queue)
323		destroy_workqueue(adapter->work_queue);
324	adapter->work_queue = NULL;
325
326}
327
328/**
329 * zfcp_adapter_enqueue - enqueue a new adapter to the list
330 * @ccw_device: pointer to the struct cc_device
331 *
332 * Returns:	struct zfcp_adapter*
333 * Enqueues an adapter at the end of the adapter list in the driver data.
334 * All adapter internal structures are set up.
335 * Proc-fs entries are also created.
336 */
337struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
338{
339	struct zfcp_adapter *adapter;
340
341	if (!get_device(&ccw_device->dev))
342		return ERR_PTR(-ENODEV);
343
344	adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
345	if (!adapter) {
346		put_device(&ccw_device->dev);
347		return ERR_PTR(-ENOMEM);
348	}
349
350	kref_init(&adapter->ref);
351
352	ccw_device->handler = NULL;
353	adapter->ccw_device = ccw_device;
354
355	INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
356	INIT_DELAYED_WORK(&adapter->scan_work, zfcp_fc_scan_ports);
357	INIT_WORK(&adapter->ns_up_work, zfcp_fc_sym_name_update);
358
359	adapter->next_port_scan = jiffies;
360
361	if (zfcp_qdio_setup(adapter))
362		goto failed;
363
364	if (zfcp_allocate_low_mem_buffers(adapter))
365		goto failed;
366
367	adapter->req_list = zfcp_reqlist_alloc();
368	if (!adapter->req_list)
369		goto failed;
370
371	if (zfcp_dbf_adapter_register(adapter))
372		goto failed;
373
374	if (zfcp_setup_adapter_work_queue(adapter))
375		goto failed;
376
377	if (zfcp_fc_gs_setup(adapter))
378		goto failed;
379
380	rwlock_init(&adapter->port_list_lock);
381	INIT_LIST_HEAD(&adapter->port_list);
382
383	INIT_LIST_HEAD(&adapter->events.list);
384	INIT_WORK(&adapter->events.work, zfcp_fc_post_event);
385	spin_lock_init(&adapter->events.list_lock);
386
387	init_waitqueue_head(&adapter->erp_ready_wq);
388	init_waitqueue_head(&adapter->erp_done_wqh);
389
390	INIT_LIST_HEAD(&adapter->erp_ready_head);
391	INIT_LIST_HEAD(&adapter->erp_running_head);
392
393	rwlock_init(&adapter->erp_lock);
394	rwlock_init(&adapter->abort_lock);
395
396	if (zfcp_erp_thread_setup(adapter))
397		goto failed;
398
399	adapter->service_level.seq_print = zfcp_print_sl;
400
401	dev_set_drvdata(&ccw_device->dev, adapter);
402
403	if (sysfs_create_group(&ccw_device->dev.kobj,
404			       &zfcp_sysfs_adapter_attrs))
405		goto failed;
406
407	/* report size limit per scatter-gather segment */
408	adapter->dma_parms.max_segment_size = ZFCP_QDIO_SBALE_LEN;
409	adapter->ccw_device->dev.dma_parms = &adapter->dma_parms;
410
411	adapter->stat_read_buf_num = FSF_STATUS_READS_RECOM;
412
413	if (!zfcp_scsi_adapter_register(adapter))
414		return adapter;
415
416failed:
417	zfcp_adapter_unregister(adapter);
418	return ERR_PTR(-ENOMEM);
419}
420
421void zfcp_adapter_unregister(struct zfcp_adapter *adapter)
422{
423	struct ccw_device *cdev = adapter->ccw_device;
424
425	cancel_delayed_work_sync(&adapter->scan_work);
426	cancel_work_sync(&adapter->stat_work);
427	cancel_work_sync(&adapter->ns_up_work);
428	zfcp_destroy_adapter_work_queue(adapter);
429
430	zfcp_fc_wka_ports_force_offline(adapter->gs);
431	zfcp_scsi_adapter_unregister(adapter);
432	sysfs_remove_group(&cdev->dev.kobj, &zfcp_sysfs_adapter_attrs);
433
434	zfcp_erp_thread_kill(adapter);
435	zfcp_dbf_adapter_unregister(adapter);
436	zfcp_qdio_destroy(adapter->qdio);
437
438	zfcp_ccw_adapter_put(adapter); /* final put to release */
439}
440
441/**
442 * zfcp_adapter_release - remove the adapter from the resource list
443 * @ref: pointer to struct kref
444 * locks:	adapter list write lock is assumed to be held by caller
445 */
446void zfcp_adapter_release(struct kref *ref)
447{
448	struct zfcp_adapter *adapter = container_of(ref, struct zfcp_adapter,
449						    ref);
450	struct ccw_device *cdev = adapter->ccw_device;
451
452	dev_set_drvdata(&adapter->ccw_device->dev, NULL);
453	zfcp_fc_gs_destroy(adapter);
454	zfcp_free_low_mem_buffers(adapter);
455	kfree(adapter->req_list);
456	kfree(adapter->fc_stats);
457	kfree(adapter->stats_reset_data);
458	kfree(adapter);
459	put_device(&cdev->dev);
460}
461
462static void zfcp_port_release(struct device *dev)
463{
464	struct zfcp_port *port = container_of(dev, struct zfcp_port, dev);
465
466	zfcp_ccw_adapter_put(port->adapter);
467	kfree(port);
468}
469
470/**
471 * zfcp_port_enqueue - enqueue port to port list of adapter
472 * @adapter: adapter where remote port is added
473 * @wwpn: WWPN of the remote port to be enqueued
474 * @status: initial status for the port
475 * @d_id: destination id of the remote port to be enqueued
476 * Returns: pointer to enqueued port on success, ERR_PTR on error
477 *
478 * All port internal structures are set up and the sysfs entry is generated.
479 * d_id is used to enqueue ports with a well known address like the Directory
480 * Service for nameserver lookup.
481 */
482struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
483				     u32 status, u32 d_id)
484{
485	struct zfcp_port *port;
486	int retval = -ENOMEM;
487
488	kref_get(&adapter->ref);
489
490	port = zfcp_get_port_by_wwpn(adapter, wwpn);
491	if (port) {
492		put_device(&port->dev);
493		retval = -EEXIST;
494		goto err_out;
495	}
496
497	port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
498	if (!port)
499		goto err_out;
500
501	rwlock_init(&port->unit_list_lock);
502	INIT_LIST_HEAD(&port->unit_list);
503	atomic_set(&port->units, 0);
504
505	INIT_WORK(&port->gid_pn_work, zfcp_fc_port_did_lookup);
506	INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
507	INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
508
509	port->adapter = adapter;
510	port->d_id = d_id;
511	port->wwpn = wwpn;
512	port->rport_task = RPORT_NONE;
513	port->dev.parent = &adapter->ccw_device->dev;
514	port->dev.groups = zfcp_port_attr_groups;
515	port->dev.release = zfcp_port_release;
516
517	if (dev_set_name(&port->dev, "0x%016llx", (unsigned long long)wwpn)) {
518		kfree(port);
519		goto err_out;
520	}
521	retval = -EINVAL;
522
523	if (device_register(&port->dev)) {
524		put_device(&port->dev);
525		goto err_out;
526	}
527
528	write_lock_irq(&adapter->port_list_lock);
529	list_add_tail(&port->list, &adapter->port_list);
530	write_unlock_irq(&adapter->port_list_lock);
531
532	atomic_or(status | ZFCP_STATUS_COMMON_RUNNING, &port->status);
533
534	return port;
535
536err_out:
537	zfcp_ccw_adapter_put(adapter);
538	return ERR_PTR(retval);
539}
540
541/**
542 * zfcp_sg_free_table - free memory used by scatterlists
543 * @sg: pointer to scatterlist
544 * @count: number of scatterlist which are to be free'ed
545 * the scatterlist are expected to reference pages always
546 */
547void zfcp_sg_free_table(struct scatterlist *sg, int count)
548{
549	int i;
550
551	for (i = 0; i < count; i++, sg++)
552		if (sg)
553			free_page((unsigned long) sg_virt(sg));
554		else
555			break;
556}
557
558/**
559 * zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
560 * @sg: pointer to struct scatterlist
561 * @count: number of scatterlists which should be assigned with buffers
562 * of size page
563 *
564 * Returns: 0 on success, -ENOMEM otherwise
565 */
566int zfcp_sg_setup_table(struct scatterlist *sg, int count)
567{
568	void *addr;
569	int i;
570
571	sg_init_table(sg, count);
572	for (i = 0; i < count; i++, sg++) {
573		addr = (void *) get_zeroed_page(GFP_KERNEL);
574		if (!addr) {
575			zfcp_sg_free_table(sg, i);
576			return -ENOMEM;
577		}
578		sg_set_buf(sg, addr, PAGE_SIZE);
579	}
580	return 0;
581}
582