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 
zfcp_cache_hw_align(const char * name,unsigned long size)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 
zfcp_init_device_configure(char * busid,u64 wwpn,u64 lun)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 
zfcp_init_device_setup(char * devstr)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 
zfcp_module_init(void)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 
zfcp_module_exit(void)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  */
zfcp_get_port_by_wwpn(struct zfcp_adapter * adapter,u64 wwpn)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 
zfcp_allocate_low_mem_buffers(struct zfcp_adapter * adapter)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 
zfcp_free_low_mem_buffers(struct zfcp_adapter * adapter)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  */
zfcp_status_read_refill(struct zfcp_adapter * adapter)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 
_zfcp_status_read_scheduler(struct work_struct * work)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 
zfcp_print_sl(struct seq_file * m,struct service_level * sl)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 
zfcp_setup_adapter_work_queue(struct zfcp_adapter * adapter)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 
zfcp_destroy_adapter_work_queue(struct zfcp_adapter * adapter)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  */
zfcp_adapter_enqueue(struct ccw_device * ccw_device)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 
zfcp_adapter_unregister(struct zfcp_adapter * adapter)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  */
zfcp_adapter_release(struct kref * ref)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  */
zfcp_device_unregister(struct device * dev,const struct attribute_group * grp)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 
zfcp_port_release(struct device * dev)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  */
zfcp_port_enqueue(struct zfcp_adapter * adapter,u64 wwpn,u32 status,u32 d_id)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  */
zfcp_sg_free_table(struct scatterlist * sg,int count)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  */
zfcp_sg_setup_table(struct scatterlist * sg,int count)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 }
604