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1 /*
2  * zfcp device driver
3  *
4  * Module interface and handling of zfcp data structures.
5  *
6  * Copyright IBM Corporation 2002, 2008
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 "zfcp_ext.h"
34 
35 #define ZFCP_BUS_ID_SIZE	20
36 
37 MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
38 MODULE_DESCRIPTION("FCP HBA driver");
39 MODULE_LICENSE("GPL");
40 
41 static char *init_device;
42 module_param_named(device, init_device, charp, 0400);
43 MODULE_PARM_DESC(device, "specify initial device");
44 
zfcp_reqlist_alloc(struct zfcp_adapter * adapter)45 static int zfcp_reqlist_alloc(struct zfcp_adapter *adapter)
46 {
47 	int idx;
48 
49 	adapter->req_list = kcalloc(REQUEST_LIST_SIZE, sizeof(struct list_head),
50 				    GFP_KERNEL);
51 	if (!adapter->req_list)
52 		return -ENOMEM;
53 
54 	for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
55 		INIT_LIST_HEAD(&adapter->req_list[idx]);
56 	return 0;
57 }
58 
59 /**
60  * zfcp_reqlist_isempty - is the request list empty
61  * @adapter: pointer to struct zfcp_adapter
62  *
63  * Returns: true if list is empty, false otherwise
64  */
zfcp_reqlist_isempty(struct zfcp_adapter * adapter)65 int zfcp_reqlist_isempty(struct zfcp_adapter *adapter)
66 {
67 	unsigned int idx;
68 
69 	for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
70 		if (!list_empty(&adapter->req_list[idx]))
71 			return 0;
72 	return 1;
73 }
74 
zfcp_init_device_configure(char * busid,u64 wwpn,u64 lun)75 static void __init zfcp_init_device_configure(char *busid, u64 wwpn, u64 lun)
76 {
77 	struct zfcp_adapter *adapter;
78 	struct zfcp_port *port;
79 	struct zfcp_unit *unit;
80 
81 	down(&zfcp_data.config_sema);
82 	read_lock_irq(&zfcp_data.config_lock);
83 	adapter = zfcp_get_adapter_by_busid(busid);
84 	if (adapter)
85 		zfcp_adapter_get(adapter);
86 	read_unlock_irq(&zfcp_data.config_lock);
87 
88 	if (!adapter)
89 		goto out_adapter;
90 	port = zfcp_port_enqueue(adapter, wwpn, 0, 0);
91 	if (IS_ERR(port))
92 		goto out_port;
93 	unit = zfcp_unit_enqueue(port, lun);
94 	if (IS_ERR(unit))
95 		goto out_unit;
96 	up(&zfcp_data.config_sema);
97 	ccw_device_set_online(adapter->ccw_device);
98 
99 	zfcp_erp_wait(adapter);
100 	wait_event(adapter->erp_done_wqh,
101 		   !(atomic_read(&unit->status) &
102 				ZFCP_STATUS_UNIT_SCSI_WORK_PENDING));
103 
104 	down(&zfcp_data.config_sema);
105 	zfcp_unit_put(unit);
106 out_unit:
107 	zfcp_port_put(port);
108 out_port:
109 	zfcp_adapter_put(adapter);
110 out_adapter:
111 	up(&zfcp_data.config_sema);
112 	return;
113 }
114 
zfcp_cache_create(int size,char * name)115 static struct kmem_cache *zfcp_cache_create(int size, char *name)
116 {
117 	int align = 1;
118 	while ((size - align) > 0)
119 		align <<= 1;
120 	return kmem_cache_create(name , size, align, 0, NULL);
121 }
122 
zfcp_init_device_setup(char * devstr)123 static void __init zfcp_init_device_setup(char *devstr)
124 {
125 	char *token;
126 	char *str;
127 	char busid[ZFCP_BUS_ID_SIZE];
128 	u64 wwpn, lun;
129 
130 	/* duplicate devstr and keep the original for sysfs presentation*/
131 	str = kmalloc(strlen(devstr) + 1, GFP_KERNEL);
132 	if (!str)
133 		return;
134 
135 	strcpy(str, devstr);
136 
137 	token = strsep(&str, ",");
138 	if (!token || strlen(token) >= ZFCP_BUS_ID_SIZE)
139 		goto err_out;
140 	strncpy(busid, token, ZFCP_BUS_ID_SIZE);
141 
142 	token = strsep(&str, ",");
143 	if (!token || strict_strtoull(token, 0, (unsigned long long *) &wwpn))
144 		goto err_out;
145 
146 	token = strsep(&str, ",");
147 	if (!token || strict_strtoull(token, 0, (unsigned long long *) &lun))
148 		goto err_out;
149 
150 	kfree(str);
151 	zfcp_init_device_configure(busid, wwpn, lun);
152 	return;
153 
154  err_out:
155 	kfree(str);
156 	pr_err("%s is not a valid SCSI device\n", devstr);
157 }
158 
zfcp_module_init(void)159 static int __init zfcp_module_init(void)
160 {
161 	int retval = -ENOMEM;
162 
163 	zfcp_data.fsf_req_qtcb_cache = zfcp_cache_create(
164 			sizeof(struct zfcp_fsf_req_qtcb), "zfcp_fsf");
165 	if (!zfcp_data.fsf_req_qtcb_cache)
166 		goto out;
167 
168 	zfcp_data.sr_buffer_cache = zfcp_cache_create(
169 			sizeof(struct fsf_status_read_buffer), "zfcp_sr");
170 	if (!zfcp_data.sr_buffer_cache)
171 		goto out_sr_cache;
172 
173 	zfcp_data.gid_pn_cache = zfcp_cache_create(
174 			sizeof(struct zfcp_gid_pn_data), "zfcp_gid");
175 	if (!zfcp_data.gid_pn_cache)
176 		goto out_gid_cache;
177 
178 	zfcp_data.work_queue = create_singlethread_workqueue("zfcp_wq");
179 
180 	sema_init(&zfcp_data.config_sema, 1);
181 	rwlock_init(&zfcp_data.config_lock);
182 
183 	zfcp_data.scsi_transport_template =
184 		fc_attach_transport(&zfcp_transport_functions);
185 	if (!zfcp_data.scsi_transport_template)
186 		goto out_transport;
187 
188 	retval = misc_register(&zfcp_cfdc_misc);
189 	if (retval) {
190 		pr_err("Registering the misc device zfcp_cfdc failed\n");
191 		goto out_misc;
192 	}
193 
194 	retval = zfcp_ccw_register();
195 	if (retval) {
196 		pr_err("The zfcp device driver could not register with "
197 		       "the common I/O layer\n");
198 		goto out_ccw_register;
199 	}
200 
201 	if (init_device)
202 		zfcp_init_device_setup(init_device);
203 	return 0;
204 
205 out_ccw_register:
206 	misc_deregister(&zfcp_cfdc_misc);
207 out_misc:
208 	fc_release_transport(zfcp_data.scsi_transport_template);
209 out_transport:
210 	kmem_cache_destroy(zfcp_data.gid_pn_cache);
211 out_gid_cache:
212 	kmem_cache_destroy(zfcp_data.sr_buffer_cache);
213 out_sr_cache:
214 	kmem_cache_destroy(zfcp_data.fsf_req_qtcb_cache);
215 out:
216 	return retval;
217 }
218 
219 module_init(zfcp_module_init);
220 
221 /**
222  * zfcp_get_unit_by_lun - find unit in unit list of port by FCP LUN
223  * @port: pointer to port to search for unit
224  * @fcp_lun: FCP LUN to search for
225  *
226  * Returns: pointer to zfcp_unit or NULL
227  */
zfcp_get_unit_by_lun(struct zfcp_port * port,u64 fcp_lun)228 struct zfcp_unit *zfcp_get_unit_by_lun(struct zfcp_port *port, u64 fcp_lun)
229 {
230 	struct zfcp_unit *unit;
231 
232 	list_for_each_entry(unit, &port->unit_list_head, list)
233 		if ((unit->fcp_lun == fcp_lun) &&
234 		    !(atomic_read(&unit->status) & ZFCP_STATUS_COMMON_REMOVE))
235 		    return unit;
236 	return NULL;
237 }
238 
239 /**
240  * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
241  * @adapter: pointer to adapter to search for port
242  * @wwpn: wwpn to search for
243  *
244  * Returns: pointer to zfcp_port or NULL
245  */
zfcp_get_port_by_wwpn(struct zfcp_adapter * adapter,u64 wwpn)246 struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
247 					u64 wwpn)
248 {
249 	struct zfcp_port *port;
250 
251 	list_for_each_entry(port, &adapter->port_list_head, list)
252 		if ((port->wwpn == wwpn) && !(atomic_read(&port->status) &
253 		      (ZFCP_STATUS_PORT_NO_WWPN | ZFCP_STATUS_COMMON_REMOVE)))
254 			return port;
255 	return NULL;
256 }
257 
zfcp_sysfs_unit_release(struct device * dev)258 static void zfcp_sysfs_unit_release(struct device *dev)
259 {
260 	kfree(container_of(dev, struct zfcp_unit, sysfs_device));
261 }
262 
263 /**
264  * zfcp_unit_enqueue - enqueue unit to unit list of a port.
265  * @port: pointer to port where unit is added
266  * @fcp_lun: FCP LUN of unit to be enqueued
267  * Returns: pointer to enqueued unit on success, ERR_PTR on error
268  * Locks: config_sema must be held to serialize changes to the unit list
269  *
270  * Sets up some unit internal structures and creates sysfs entry.
271  */
zfcp_unit_enqueue(struct zfcp_port * port,u64 fcp_lun)272 struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
273 {
274 	struct zfcp_unit *unit;
275 
276 	unit = kzalloc(sizeof(struct zfcp_unit), GFP_KERNEL);
277 	if (!unit)
278 		return ERR_PTR(-ENOMEM);
279 
280 	atomic_set(&unit->refcount, 0);
281 	init_waitqueue_head(&unit->remove_wq);
282 
283 	unit->port = port;
284 	unit->fcp_lun = fcp_lun;
285 
286 	dev_set_name(&unit->sysfs_device, "0x%016llx",
287 		     (unsigned long long) fcp_lun);
288 	unit->sysfs_device.parent = &port->sysfs_device;
289 	unit->sysfs_device.release = zfcp_sysfs_unit_release;
290 	dev_set_drvdata(&unit->sysfs_device, unit);
291 
292 	/* mark unit unusable as long as sysfs registration is not complete */
293 	atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
294 
295 	spin_lock_init(&unit->latencies.lock);
296 	unit->latencies.write.channel.min = 0xFFFFFFFF;
297 	unit->latencies.write.fabric.min = 0xFFFFFFFF;
298 	unit->latencies.read.channel.min = 0xFFFFFFFF;
299 	unit->latencies.read.fabric.min = 0xFFFFFFFF;
300 	unit->latencies.cmd.channel.min = 0xFFFFFFFF;
301 	unit->latencies.cmd.fabric.min = 0xFFFFFFFF;
302 
303 	read_lock_irq(&zfcp_data.config_lock);
304 	if (zfcp_get_unit_by_lun(port, fcp_lun)) {
305 		read_unlock_irq(&zfcp_data.config_lock);
306 		goto err_out_free;
307 	}
308 	read_unlock_irq(&zfcp_data.config_lock);
309 
310 	if (device_register(&unit->sysfs_device))
311 		goto err_out_free;
312 
313 	if (sysfs_create_group(&unit->sysfs_device.kobj,
314 			       &zfcp_sysfs_unit_attrs)) {
315 		device_unregister(&unit->sysfs_device);
316 		return ERR_PTR(-EIO);
317 	}
318 
319 	zfcp_unit_get(unit);
320 
321 	write_lock_irq(&zfcp_data.config_lock);
322 	list_add_tail(&unit->list, &port->unit_list_head);
323 	atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
324 	atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status);
325 
326 	write_unlock_irq(&zfcp_data.config_lock);
327 
328 	zfcp_port_get(port);
329 
330 	return unit;
331 
332 err_out_free:
333 	kfree(unit);
334 	return ERR_PTR(-EINVAL);
335 }
336 
337 /**
338  * zfcp_unit_dequeue - dequeue unit
339  * @unit: pointer to zfcp_unit
340  *
341  * waits until all work is done on unit and removes it then from the unit->list
342  * of the associated port.
343  */
zfcp_unit_dequeue(struct zfcp_unit * unit)344 void zfcp_unit_dequeue(struct zfcp_unit *unit)
345 {
346 	wait_event(unit->remove_wq, atomic_read(&unit->refcount) == 0);
347 	write_lock_irq(&zfcp_data.config_lock);
348 	list_del(&unit->list);
349 	write_unlock_irq(&zfcp_data.config_lock);
350 	zfcp_port_put(unit->port);
351 	sysfs_remove_group(&unit->sysfs_device.kobj, &zfcp_sysfs_unit_attrs);
352 	device_unregister(&unit->sysfs_device);
353 }
354 
zfcp_allocate_low_mem_buffers(struct zfcp_adapter * adapter)355 static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
356 {
357 	/* must only be called with zfcp_data.config_sema taken */
358 	adapter->pool.fsf_req_erp =
359 		mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
360 	if (!adapter->pool.fsf_req_erp)
361 		return -ENOMEM;
362 
363 	adapter->pool.fsf_req_scsi =
364 		mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
365 	if (!adapter->pool.fsf_req_scsi)
366 		return -ENOMEM;
367 
368 	adapter->pool.fsf_req_abort =
369 		mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
370 	if (!adapter->pool.fsf_req_abort)
371 		return -ENOMEM;
372 
373 	adapter->pool.fsf_req_status_read =
374 		mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
375 					    sizeof(struct zfcp_fsf_req));
376 	if (!adapter->pool.fsf_req_status_read)
377 		return -ENOMEM;
378 
379 	adapter->pool.data_status_read =
380 		mempool_create_slab_pool(FSF_STATUS_READS_RECOM,
381 					 zfcp_data.sr_buffer_cache);
382 	if (!adapter->pool.data_status_read)
383 		return -ENOMEM;
384 
385 	adapter->pool.data_gid_pn =
386 		mempool_create_slab_pool(1, zfcp_data.gid_pn_cache);
387 	if (!adapter->pool.data_gid_pn)
388 		return -ENOMEM;
389 
390 	return 0;
391 }
392 
zfcp_free_low_mem_buffers(struct zfcp_adapter * adapter)393 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
394 {
395 	/* zfcp_data.config_sema must be held */
396 	if (adapter->pool.fsf_req_erp)
397 		mempool_destroy(adapter->pool.fsf_req_erp);
398 	if (adapter->pool.fsf_req_scsi)
399 		mempool_destroy(adapter->pool.fsf_req_scsi);
400 	if (adapter->pool.fsf_req_abort)
401 		mempool_destroy(adapter->pool.fsf_req_abort);
402 	if (adapter->pool.fsf_req_status_read)
403 		mempool_destroy(adapter->pool.fsf_req_status_read);
404 	if (adapter->pool.data_status_read)
405 		mempool_destroy(adapter->pool.data_status_read);
406 	if (adapter->pool.data_gid_pn)
407 		mempool_destroy(adapter->pool.data_gid_pn);
408 }
409 
410 /**
411  * zfcp_status_read_refill - refill the long running status_read_requests
412  * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
413  *
414  * Returns: 0 on success, 1 otherwise
415  *
416  * if there are 16 or more status_read requests missing an adapter_reopen
417  * is triggered
418  */
zfcp_status_read_refill(struct zfcp_adapter * adapter)419 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
420 {
421 	while (atomic_read(&adapter->stat_miss) > 0)
422 		if (zfcp_fsf_status_read(adapter)) {
423 			if (atomic_read(&adapter->stat_miss) >= 16) {
424 				zfcp_erp_adapter_reopen(adapter, 0, 103, NULL);
425 				return 1;
426 			}
427 			break;
428 		} else
429 			atomic_dec(&adapter->stat_miss);
430 	return 0;
431 }
432 
_zfcp_status_read_scheduler(struct work_struct * work)433 static void _zfcp_status_read_scheduler(struct work_struct *work)
434 {
435 	zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
436 					     stat_work));
437 }
438 
zfcp_print_sl(struct seq_file * m,struct service_level * sl)439 static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
440 {
441 	struct zfcp_adapter *adapter =
442 		container_of(sl, struct zfcp_adapter, service_level);
443 
444 	seq_printf(m, "zfcp: %s microcode level %x\n",
445 		   dev_name(&adapter->ccw_device->dev),
446 		   adapter->fsf_lic_version);
447 }
448 
449 /**
450  * zfcp_adapter_enqueue - enqueue a new adapter to the list
451  * @ccw_device: pointer to the struct cc_device
452  *
453  * Returns:	0             if a new adapter was successfully enqueued
454  *		-ENOMEM       if alloc failed
455  * Enqueues an adapter at the end of the adapter list in the driver data.
456  * All adapter internal structures are set up.
457  * Proc-fs entries are also created.
458  * locks:	config_sema must be held to serialise changes to the adapter list
459  */
zfcp_adapter_enqueue(struct ccw_device * ccw_device)460 int zfcp_adapter_enqueue(struct ccw_device *ccw_device)
461 {
462 	struct zfcp_adapter *adapter;
463 
464 	/*
465 	 * Note: It is safe to release the list_lock, as any list changes
466 	 * are protected by the config_sema, which must be held to get here
467 	 */
468 
469 	adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
470 	if (!adapter)
471 		return -ENOMEM;
472 
473 	ccw_device->handler = NULL;
474 	adapter->ccw_device = ccw_device;
475 	atomic_set(&adapter->refcount, 0);
476 
477 	if (zfcp_qdio_allocate(adapter))
478 		goto qdio_allocate_failed;
479 
480 	if (zfcp_allocate_low_mem_buffers(adapter))
481 		goto failed_low_mem_buffers;
482 
483 	if (zfcp_reqlist_alloc(adapter))
484 		goto failed_low_mem_buffers;
485 
486 	if (zfcp_adapter_debug_register(adapter))
487 		goto debug_register_failed;
488 
489 	init_waitqueue_head(&adapter->remove_wq);
490 	init_waitqueue_head(&adapter->erp_thread_wqh);
491 	init_waitqueue_head(&adapter->erp_done_wqh);
492 
493 	INIT_LIST_HEAD(&adapter->port_list_head);
494 	INIT_LIST_HEAD(&adapter->erp_ready_head);
495 	INIT_LIST_HEAD(&adapter->erp_running_head);
496 
497 	spin_lock_init(&adapter->req_list_lock);
498 
499 	spin_lock_init(&adapter->hba_dbf_lock);
500 	spin_lock_init(&adapter->san_dbf_lock);
501 	spin_lock_init(&adapter->scsi_dbf_lock);
502 	spin_lock_init(&adapter->rec_dbf_lock);
503 	spin_lock_init(&adapter->req_q_lock);
504 
505 	rwlock_init(&adapter->erp_lock);
506 	rwlock_init(&adapter->abort_lock);
507 
508 	sema_init(&adapter->erp_ready_sem, 0);
509 
510 	INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
511 	INIT_WORK(&adapter->scan_work, _zfcp_scan_ports_later);
512 
513 	adapter->service_level.seq_print = zfcp_print_sl;
514 
515 	/* mark adapter unusable as long as sysfs registration is not complete */
516 	atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
517 
518 	dev_set_drvdata(&ccw_device->dev, adapter);
519 
520 	if (sysfs_create_group(&ccw_device->dev.kobj,
521 			       &zfcp_sysfs_adapter_attrs))
522 		goto sysfs_failed;
523 
524 	atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
525 	zfcp_fc_nameserver_init(adapter);
526 
527 	if (!zfcp_adapter_scsi_register(adapter))
528 		return 0;
529 
530 sysfs_failed:
531 	zfcp_adapter_debug_unregister(adapter);
532 debug_register_failed:
533 	dev_set_drvdata(&ccw_device->dev, NULL);
534 	kfree(adapter->req_list);
535 failed_low_mem_buffers:
536 	zfcp_free_low_mem_buffers(adapter);
537 qdio_allocate_failed:
538 	zfcp_qdio_free(adapter);
539 	kfree(adapter);
540 	return -ENOMEM;
541 }
542 
543 /**
544  * zfcp_adapter_dequeue - remove the adapter from the resource list
545  * @adapter: pointer to struct zfcp_adapter which should be removed
546  * locks:	adapter list write lock is assumed to be held by caller
547  */
zfcp_adapter_dequeue(struct zfcp_adapter * adapter)548 void zfcp_adapter_dequeue(struct zfcp_adapter *adapter)
549 {
550 	int retval = 0;
551 	unsigned long flags;
552 
553 	cancel_work_sync(&adapter->scan_work);
554 	cancel_work_sync(&adapter->stat_work);
555 	zfcp_adapter_scsi_unregister(adapter);
556 	sysfs_remove_group(&adapter->ccw_device->dev.kobj,
557 			   &zfcp_sysfs_adapter_attrs);
558 	dev_set_drvdata(&adapter->ccw_device->dev, NULL);
559 	/* sanity check: no pending FSF requests */
560 	spin_lock_irqsave(&adapter->req_list_lock, flags);
561 	retval = zfcp_reqlist_isempty(adapter);
562 	spin_unlock_irqrestore(&adapter->req_list_lock, flags);
563 	if (!retval)
564 		return;
565 
566 	zfcp_adapter_debug_unregister(adapter);
567 	zfcp_qdio_free(adapter);
568 	zfcp_free_low_mem_buffers(adapter);
569 	kfree(adapter->req_list);
570 	kfree(adapter->fc_stats);
571 	kfree(adapter->stats_reset_data);
572 	kfree(adapter);
573 }
574 
zfcp_sysfs_port_release(struct device * dev)575 static void zfcp_sysfs_port_release(struct device *dev)
576 {
577 	kfree(container_of(dev, struct zfcp_port, sysfs_device));
578 }
579 
580 /**
581  * zfcp_port_enqueue - enqueue port to port list of adapter
582  * @adapter: adapter where remote port is added
583  * @wwpn: WWPN of the remote port to be enqueued
584  * @status: initial status for the port
585  * @d_id: destination id of the remote port to be enqueued
586  * Returns: pointer to enqueued port on success, ERR_PTR on error
587  * Locks: config_sema must be held to serialize changes to the port list
588  *
589  * All port internal structures are set up and the sysfs entry is generated.
590  * d_id is used to enqueue ports with a well known address like the Directory
591  * Service for nameserver lookup.
592  */
zfcp_port_enqueue(struct zfcp_adapter * adapter,u64 wwpn,u32 status,u32 d_id)593 struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
594 				     u32 status, u32 d_id)
595 {
596 	struct zfcp_port *port;
597 	int retval;
598 
599 	port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
600 	if (!port)
601 		return ERR_PTR(-ENOMEM);
602 
603 	init_waitqueue_head(&port->remove_wq);
604 	INIT_LIST_HEAD(&port->unit_list_head);
605 	INIT_WORK(&port->gid_pn_work, zfcp_erp_port_strategy_open_lookup);
606 
607 	port->adapter = adapter;
608 	port->d_id = d_id;
609 	port->wwpn = wwpn;
610 
611 	/* mark port unusable as long as sysfs registration is not complete */
612 	atomic_set_mask(status | ZFCP_STATUS_COMMON_REMOVE, &port->status);
613 	atomic_set(&port->refcount, 0);
614 
615 	dev_set_name(&port->sysfs_device, "0x%016llx",
616 		     (unsigned long long)wwpn);
617 	port->sysfs_device.parent = &adapter->ccw_device->dev;
618 
619 	port->sysfs_device.release = zfcp_sysfs_port_release;
620 	dev_set_drvdata(&port->sysfs_device, port);
621 
622 	read_lock_irq(&zfcp_data.config_lock);
623 	if (!(status & ZFCP_STATUS_PORT_NO_WWPN))
624 		if (zfcp_get_port_by_wwpn(adapter, wwpn)) {
625 			read_unlock_irq(&zfcp_data.config_lock);
626 			goto err_out_free;
627 		}
628 	read_unlock_irq(&zfcp_data.config_lock);
629 
630 	if (device_register(&port->sysfs_device))
631 		goto err_out_free;
632 
633 	retval = sysfs_create_group(&port->sysfs_device.kobj,
634 				    &zfcp_sysfs_port_attrs);
635 
636 	if (retval) {
637 		device_unregister(&port->sysfs_device);
638 		goto err_out;
639 	}
640 
641 	zfcp_port_get(port);
642 
643 	write_lock_irq(&zfcp_data.config_lock);
644 	list_add_tail(&port->list, &adapter->port_list_head);
645 	atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &port->status);
646 	atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &port->status);
647 
648 	write_unlock_irq(&zfcp_data.config_lock);
649 
650 	zfcp_adapter_get(adapter);
651 	return port;
652 
653 err_out_free:
654 	kfree(port);
655 err_out:
656 	return ERR_PTR(-EINVAL);
657 }
658 
659 /**
660  * zfcp_port_dequeue - dequeues a port from the port list of the adapter
661  * @port: pointer to struct zfcp_port which should be removed
662  */
zfcp_port_dequeue(struct zfcp_port * port)663 void zfcp_port_dequeue(struct zfcp_port *port)
664 {
665 	wait_event(port->remove_wq, atomic_read(&port->refcount) == 0);
666 	write_lock_irq(&zfcp_data.config_lock);
667 	list_del(&port->list);
668 	write_unlock_irq(&zfcp_data.config_lock);
669 	if (port->rport)
670 		fc_remote_port_delete(port->rport);
671 	port->rport = NULL;
672 	zfcp_adapter_put(port->adapter);
673 	sysfs_remove_group(&port->sysfs_device.kobj, &zfcp_sysfs_port_attrs);
674 	device_unregister(&port->sysfs_device);
675 }
676 
677 /**
678  * zfcp_sg_free_table - free memory used by scatterlists
679  * @sg: pointer to scatterlist
680  * @count: number of scatterlist which are to be free'ed
681  * the scatterlist are expected to reference pages always
682  */
zfcp_sg_free_table(struct scatterlist * sg,int count)683 void zfcp_sg_free_table(struct scatterlist *sg, int count)
684 {
685 	int i;
686 
687 	for (i = 0; i < count; i++, sg++)
688 		if (sg)
689 			free_page((unsigned long) sg_virt(sg));
690 		else
691 			break;
692 }
693 
694 /**
695  * zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
696  * @sg: pointer to struct scatterlist
697  * @count: number of scatterlists which should be assigned with buffers
698  * of size page
699  *
700  * Returns: 0 on success, -ENOMEM otherwise
701  */
zfcp_sg_setup_table(struct scatterlist * sg,int count)702 int zfcp_sg_setup_table(struct scatterlist *sg, int count)
703 {
704 	void *addr;
705 	int i;
706 
707 	sg_init_table(sg, count);
708 	for (i = 0; i < count; i++, sg++) {
709 		addr = (void *) get_zeroed_page(GFP_KERNEL);
710 		if (!addr) {
711 			zfcp_sg_free_table(sg, i);
712 			return -ENOMEM;
713 		}
714 		sg_set_buf(sg, addr, PAGE_SIZE);
715 	}
716 	return 0;
717 }
718