xref: /openbmc/linux/drivers/s390/crypto/ap_bus.c (revision 55fd7e02)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright IBM Corp. 2006, 2012
4  * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
5  *	      Martin Schwidefsky <schwidefsky@de.ibm.com>
6  *	      Ralph Wuerthner <rwuerthn@de.ibm.com>
7  *	      Felix Beck <felix.beck@de.ibm.com>
8  *	      Holger Dengler <hd@linux.vnet.ibm.com>
9  *
10  * Adjunct processor bus.
11  */
12 
13 #define KMSG_COMPONENT "ap"
14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
15 
16 #include <linux/kernel_stat.h>
17 #include <linux/moduleparam.h>
18 #include <linux/init.h>
19 #include <linux/delay.h>
20 #include <linux/err.h>
21 #include <linux/freezer.h>
22 #include <linux/interrupt.h>
23 #include <linux/workqueue.h>
24 #include <linux/slab.h>
25 #include <linux/notifier.h>
26 #include <linux/kthread.h>
27 #include <linux/mutex.h>
28 #include <asm/airq.h>
29 #include <linux/atomic.h>
30 #include <asm/isc.h>
31 #include <linux/hrtimer.h>
32 #include <linux/ktime.h>
33 #include <asm/facility.h>
34 #include <linux/crypto.h>
35 #include <linux/mod_devicetable.h>
36 #include <linux/debugfs.h>
37 #include <linux/ctype.h>
38 
39 #include "ap_bus.h"
40 #include "ap_debug.h"
41 
42 /*
43  * Module parameters; note though this file itself isn't modular.
44  */
45 int ap_domain_index = -1;	/* Adjunct Processor Domain Index */
46 static DEFINE_SPINLOCK(ap_domain_lock);
47 module_param_named(domain, ap_domain_index, int, 0440);
48 MODULE_PARM_DESC(domain, "domain index for ap devices");
49 EXPORT_SYMBOL(ap_domain_index);
50 
51 static int ap_thread_flag;
52 module_param_named(poll_thread, ap_thread_flag, int, 0440);
53 MODULE_PARM_DESC(poll_thread, "Turn on/off poll thread, default is 0 (off).");
54 
55 static char *apm_str;
56 module_param_named(apmask, apm_str, charp, 0440);
57 MODULE_PARM_DESC(apmask, "AP bus adapter mask.");
58 
59 static char *aqm_str;
60 module_param_named(aqmask, aqm_str, charp, 0440);
61 MODULE_PARM_DESC(aqmask, "AP bus domain mask.");
62 
63 static struct device *ap_root_device;
64 
65 /* Hashtable of all queue devices on the AP bus */
66 DEFINE_HASHTABLE(ap_queues, 8);
67 /* lock used for the ap_queues hashtable */
68 DEFINE_SPINLOCK(ap_queues_lock);
69 
70 /* Default permissions (ioctl, card and domain masking) */
71 struct ap_perms ap_perms;
72 EXPORT_SYMBOL(ap_perms);
73 DEFINE_MUTEX(ap_perms_mutex);
74 EXPORT_SYMBOL(ap_perms_mutex);
75 
76 static struct ap_config_info *ap_configuration;
77 static bool initialised;
78 
79 /*
80  * AP bus related debug feature things.
81  */
82 debug_info_t *ap_dbf_info;
83 
84 /*
85  * Workqueue timer for bus rescan.
86  */
87 static struct timer_list ap_config_timer;
88 static int ap_config_time = AP_CONFIG_TIME;
89 static void ap_scan_bus(struct work_struct *);
90 static DECLARE_WORK(ap_scan_work, ap_scan_bus);
91 
92 /*
93  * Tasklet & timer for AP request polling and interrupts
94  */
95 static void ap_tasklet_fn(unsigned long);
96 static DECLARE_TASKLET(ap_tasklet, ap_tasklet_fn, 0);
97 static DECLARE_WAIT_QUEUE_HEAD(ap_poll_wait);
98 static struct task_struct *ap_poll_kthread;
99 static DEFINE_MUTEX(ap_poll_thread_mutex);
100 static DEFINE_SPINLOCK(ap_poll_timer_lock);
101 static struct hrtimer ap_poll_timer;
102 /*
103  * In LPAR poll with 4kHz frequency. Poll every 250000 nanoseconds.
104  * If z/VM change to 1500000 nanoseconds to adjust to z/VM polling.
105  */
106 static unsigned long long poll_timeout = 250000;
107 
108 /* Maximum domain id */
109 static int ap_max_domain_id;
110 
111 static struct bus_type ap_bus_type;
112 
113 /* Adapter interrupt definitions */
114 static void ap_interrupt_handler(struct airq_struct *airq, bool floating);
115 
116 static int ap_airq_flag;
117 
118 static struct airq_struct ap_airq = {
119 	.handler = ap_interrupt_handler,
120 	.isc = AP_ISC,
121 };
122 
123 /**
124  * ap_using_interrupts() - Returns non-zero if interrupt support is
125  * available.
126  */
127 static inline int ap_using_interrupts(void)
128 {
129 	return ap_airq_flag;
130 }
131 
132 /**
133  * ap_airq_ptr() - Get the address of the adapter interrupt indicator
134  *
135  * Returns the address of the local-summary-indicator of the adapter
136  * interrupt handler for AP, or NULL if adapter interrupts are not
137  * available.
138  */
139 void *ap_airq_ptr(void)
140 {
141 	if (ap_using_interrupts())
142 		return ap_airq.lsi_ptr;
143 	return NULL;
144 }
145 
146 /**
147  * ap_interrupts_available(): Test if AP interrupts are available.
148  *
149  * Returns 1 if AP interrupts are available.
150  */
151 static int ap_interrupts_available(void)
152 {
153 	return test_facility(65);
154 }
155 
156 /**
157  * ap_configuration_available(): Test if AP configuration
158  * information is available.
159  *
160  * Returns 1 if AP configuration information is available.
161  */
162 static int ap_configuration_available(void)
163 {
164 	return test_facility(12);
165 }
166 
167 /**
168  * ap_apft_available(): Test if AP facilities test (APFT)
169  * facility is available.
170  *
171  * Returns 1 if APFT is is available.
172  */
173 static int ap_apft_available(void)
174 {
175 	return test_facility(15);
176 }
177 
178 /*
179  * ap_qact_available(): Test if the PQAP(QACT) subfunction is available.
180  *
181  * Returns 1 if the QACT subfunction is available.
182  */
183 static inline int ap_qact_available(void)
184 {
185 	if (ap_configuration)
186 		return ap_configuration->qact;
187 	return 0;
188 }
189 
190 /*
191  * ap_query_configuration(): Fetch cryptographic config info
192  *
193  * Returns the ap configuration info fetched via PQAP(QCI).
194  * On success 0 is returned, on failure a negative errno
195  * is returned, e.g. if the PQAP(QCI) instruction is not
196  * available, the return value will be -EOPNOTSUPP.
197  */
198 static inline int ap_query_configuration(struct ap_config_info *info)
199 {
200 	if (!ap_configuration_available())
201 		return -EOPNOTSUPP;
202 	if (!info)
203 		return -EINVAL;
204 	return ap_qci(info);
205 }
206 
207 /**
208  * ap_init_configuration(): Allocate and query configuration array.
209  */
210 static void ap_init_configuration(void)
211 {
212 	if (!ap_configuration_available())
213 		return;
214 
215 	ap_configuration = kzalloc(sizeof(*ap_configuration), GFP_KERNEL);
216 	if (!ap_configuration)
217 		return;
218 	if (ap_query_configuration(ap_configuration) != 0) {
219 		kfree(ap_configuration);
220 		ap_configuration = NULL;
221 		return;
222 	}
223 }
224 
225 /*
226  * ap_test_config(): helper function to extract the nrth bit
227  *		     within the unsigned int array field.
228  */
229 static inline int ap_test_config(unsigned int *field, unsigned int nr)
230 {
231 	return ap_test_bit((field + (nr >> 5)), (nr & 0x1f));
232 }
233 
234 /*
235  * ap_test_config_card_id(): Test, whether an AP card ID is configured.
236  * @id AP card ID
237  *
238  * Returns 0 if the card is not configured
239  *	   1 if the card is configured or
240  *	     if the configuration information is not available
241  */
242 static inline int ap_test_config_card_id(unsigned int id)
243 {
244 	if (!ap_configuration)	/* QCI not supported */
245 		/* only ids 0...3F may be probed */
246 		return id < 0x40 ? 1 : 0;
247 	return ap_test_config(ap_configuration->apm, id);
248 }
249 
250 /*
251  * ap_test_config_usage_domain(): Test, whether an AP usage domain
252  * is configured.
253  * @domain AP usage domain ID
254  *
255  * Returns 0 if the usage domain is not configured
256  *	   1 if the usage domain is configured or
257  *	     if the configuration information is not available
258  */
259 int ap_test_config_usage_domain(unsigned int domain)
260 {
261 	if (!ap_configuration)	/* QCI not supported */
262 		return domain < 16;
263 	return ap_test_config(ap_configuration->aqm, domain);
264 }
265 EXPORT_SYMBOL(ap_test_config_usage_domain);
266 
267 /*
268  * ap_test_config_ctrl_domain(): Test, whether an AP control domain
269  * is configured.
270  * @domain AP control domain ID
271  *
272  * Returns 1 if the control domain is configured
273  *	   0 in all other cases
274  */
275 int ap_test_config_ctrl_domain(unsigned int domain)
276 {
277 	if (!ap_configuration)	/* QCI not supported */
278 		return 0;
279 	return ap_test_config(ap_configuration->adm, domain);
280 }
281 EXPORT_SYMBOL(ap_test_config_ctrl_domain);
282 
283 /**
284  * ap_query_queue(): Check if an AP queue is available.
285  * @qid: The AP queue number
286  * @queue_depth: Pointer to queue depth value
287  * @device_type: Pointer to device type value
288  * @facilities: Pointer to facility indicator
289  */
290 static int ap_query_queue(ap_qid_t qid, int *queue_depth, int *device_type,
291 			  unsigned int *facilities)
292 {
293 	struct ap_queue_status status;
294 	unsigned long info;
295 	int nd;
296 
297 	if (!ap_test_config_card_id(AP_QID_CARD(qid)))
298 		return -ENODEV;
299 
300 	status = ap_test_queue(qid, ap_apft_available(), &info);
301 	switch (status.response_code) {
302 	case AP_RESPONSE_NORMAL:
303 		*queue_depth = (int)(info & 0xff);
304 		*device_type = (int)((info >> 24) & 0xff);
305 		*facilities = (unsigned int)(info >> 32);
306 		/* Update maximum domain id */
307 		nd = (info >> 16) & 0xff;
308 		/* if N bit is available, z13 and newer */
309 		if ((info & (1UL << 57)) && nd > 0)
310 			ap_max_domain_id = nd;
311 		else /* older machine types */
312 			ap_max_domain_id = 15;
313 		switch (*device_type) {
314 			/* For CEX2 and CEX3 the available functions
315 			 * are not reflected by the facilities bits.
316 			 * Instead it is coded into the type. So here
317 			 * modify the function bits based on the type.
318 			 */
319 		case AP_DEVICE_TYPE_CEX2A:
320 		case AP_DEVICE_TYPE_CEX3A:
321 			*facilities |= 0x08000000;
322 			break;
323 		case AP_DEVICE_TYPE_CEX2C:
324 		case AP_DEVICE_TYPE_CEX3C:
325 			*facilities |= 0x10000000;
326 			break;
327 		default:
328 			break;
329 		}
330 		return 0;
331 	case AP_RESPONSE_Q_NOT_AVAIL:
332 	case AP_RESPONSE_DECONFIGURED:
333 	case AP_RESPONSE_CHECKSTOPPED:
334 	case AP_RESPONSE_INVALID_ADDRESS:
335 		return -ENODEV;
336 	case AP_RESPONSE_RESET_IN_PROGRESS:
337 	case AP_RESPONSE_OTHERWISE_CHANGED:
338 	case AP_RESPONSE_BUSY:
339 		return -EBUSY;
340 	default:
341 		BUG();
342 	}
343 }
344 
345 void ap_wait(enum ap_wait wait)
346 {
347 	ktime_t hr_time;
348 
349 	switch (wait) {
350 	case AP_WAIT_AGAIN:
351 	case AP_WAIT_INTERRUPT:
352 		if (ap_using_interrupts())
353 			break;
354 		if (ap_poll_kthread) {
355 			wake_up(&ap_poll_wait);
356 			break;
357 		}
358 		fallthrough;
359 	case AP_WAIT_TIMEOUT:
360 		spin_lock_bh(&ap_poll_timer_lock);
361 		if (!hrtimer_is_queued(&ap_poll_timer)) {
362 			hr_time = poll_timeout;
363 			hrtimer_forward_now(&ap_poll_timer, hr_time);
364 			hrtimer_restart(&ap_poll_timer);
365 		}
366 		spin_unlock_bh(&ap_poll_timer_lock);
367 		break;
368 	case AP_WAIT_NONE:
369 	default:
370 		break;
371 	}
372 }
373 
374 /**
375  * ap_request_timeout(): Handling of request timeouts
376  * @t: timer making this callback
377  *
378  * Handles request timeouts.
379  */
380 void ap_request_timeout(struct timer_list *t)
381 {
382 	struct ap_queue *aq = from_timer(aq, t, timeout);
383 
384 	spin_lock_bh(&aq->lock);
385 	ap_wait(ap_sm_event(aq, AP_EVENT_TIMEOUT));
386 	spin_unlock_bh(&aq->lock);
387 }
388 
389 /**
390  * ap_poll_timeout(): AP receive polling for finished AP requests.
391  * @unused: Unused pointer.
392  *
393  * Schedules the AP tasklet using a high resolution timer.
394  */
395 static enum hrtimer_restart ap_poll_timeout(struct hrtimer *unused)
396 {
397 	tasklet_schedule(&ap_tasklet);
398 	return HRTIMER_NORESTART;
399 }
400 
401 /**
402  * ap_interrupt_handler() - Schedule ap_tasklet on interrupt
403  * @airq: pointer to adapter interrupt descriptor
404  */
405 static void ap_interrupt_handler(struct airq_struct *airq, bool floating)
406 {
407 	inc_irq_stat(IRQIO_APB);
408 	tasklet_schedule(&ap_tasklet);
409 }
410 
411 /**
412  * ap_tasklet_fn(): Tasklet to poll all AP devices.
413  * @dummy: Unused variable
414  *
415  * Poll all AP devices on the bus.
416  */
417 static void ap_tasklet_fn(unsigned long dummy)
418 {
419 	int bkt;
420 	struct ap_queue *aq;
421 	enum ap_wait wait = AP_WAIT_NONE;
422 
423 	/* Reset the indicator if interrupts are used. Thus new interrupts can
424 	 * be received. Doing it in the beginning of the tasklet is therefor
425 	 * important that no requests on any AP get lost.
426 	 */
427 	if (ap_using_interrupts())
428 		xchg(ap_airq.lsi_ptr, 0);
429 
430 	spin_lock_bh(&ap_queues_lock);
431 	hash_for_each(ap_queues, bkt, aq, hnode) {
432 		spin_lock_bh(&aq->lock);
433 		wait = min(wait, ap_sm_event_loop(aq, AP_EVENT_POLL));
434 		spin_unlock_bh(&aq->lock);
435 	}
436 	spin_unlock_bh(&ap_queues_lock);
437 
438 	ap_wait(wait);
439 }
440 
441 static int ap_pending_requests(void)
442 {
443 	int bkt;
444 	struct ap_queue *aq;
445 
446 	spin_lock_bh(&ap_queues_lock);
447 	hash_for_each(ap_queues, bkt, aq, hnode) {
448 		if (aq->queue_count == 0)
449 			continue;
450 		spin_unlock_bh(&ap_queues_lock);
451 		return 1;
452 	}
453 	spin_unlock_bh(&ap_queues_lock);
454 	return 0;
455 }
456 
457 /**
458  * ap_poll_thread(): Thread that polls for finished requests.
459  * @data: Unused pointer
460  *
461  * AP bus poll thread. The purpose of this thread is to poll for
462  * finished requests in a loop if there is a "free" cpu - that is
463  * a cpu that doesn't have anything better to do. The polling stops
464  * as soon as there is another task or if all messages have been
465  * delivered.
466  */
467 static int ap_poll_thread(void *data)
468 {
469 	DECLARE_WAITQUEUE(wait, current);
470 
471 	set_user_nice(current, MAX_NICE);
472 	set_freezable();
473 	while (!kthread_should_stop()) {
474 		add_wait_queue(&ap_poll_wait, &wait);
475 		set_current_state(TASK_INTERRUPTIBLE);
476 		if (!ap_pending_requests()) {
477 			schedule();
478 			try_to_freeze();
479 		}
480 		set_current_state(TASK_RUNNING);
481 		remove_wait_queue(&ap_poll_wait, &wait);
482 		if (need_resched()) {
483 			schedule();
484 			try_to_freeze();
485 			continue;
486 		}
487 		ap_tasklet_fn(0);
488 	}
489 
490 	return 0;
491 }
492 
493 static int ap_poll_thread_start(void)
494 {
495 	int rc;
496 
497 	if (ap_using_interrupts() || ap_poll_kthread)
498 		return 0;
499 	mutex_lock(&ap_poll_thread_mutex);
500 	ap_poll_kthread = kthread_run(ap_poll_thread, NULL, "appoll");
501 	rc = PTR_ERR_OR_ZERO(ap_poll_kthread);
502 	if (rc)
503 		ap_poll_kthread = NULL;
504 	mutex_unlock(&ap_poll_thread_mutex);
505 	return rc;
506 }
507 
508 static void ap_poll_thread_stop(void)
509 {
510 	if (!ap_poll_kthread)
511 		return;
512 	mutex_lock(&ap_poll_thread_mutex);
513 	kthread_stop(ap_poll_kthread);
514 	ap_poll_kthread = NULL;
515 	mutex_unlock(&ap_poll_thread_mutex);
516 }
517 
518 #define is_card_dev(x) ((x)->parent == ap_root_device)
519 #define is_queue_dev(x) ((x)->parent != ap_root_device)
520 
521 /**
522  * ap_bus_match()
523  * @dev: Pointer to device
524  * @drv: Pointer to device_driver
525  *
526  * AP bus driver registration/unregistration.
527  */
528 static int ap_bus_match(struct device *dev, struct device_driver *drv)
529 {
530 	struct ap_driver *ap_drv = to_ap_drv(drv);
531 	struct ap_device_id *id;
532 
533 	/*
534 	 * Compare device type of the device with the list of
535 	 * supported types of the device_driver.
536 	 */
537 	for (id = ap_drv->ids; id->match_flags; id++) {
538 		if (is_card_dev(dev) &&
539 		    id->match_flags & AP_DEVICE_ID_MATCH_CARD_TYPE &&
540 		    id->dev_type == to_ap_dev(dev)->device_type)
541 			return 1;
542 		if (is_queue_dev(dev) &&
543 		    id->match_flags & AP_DEVICE_ID_MATCH_QUEUE_TYPE &&
544 		    id->dev_type == to_ap_dev(dev)->device_type)
545 			return 1;
546 	}
547 	return 0;
548 }
549 
550 /**
551  * ap_uevent(): Uevent function for AP devices.
552  * @dev: Pointer to device
553  * @env: Pointer to kobj_uevent_env
554  *
555  * It sets up a single environment variable DEV_TYPE which contains the
556  * hardware device type.
557  */
558 static int ap_uevent(struct device *dev, struct kobj_uevent_env *env)
559 {
560 	struct ap_device *ap_dev = to_ap_dev(dev);
561 	int retval = 0;
562 
563 	if (!ap_dev)
564 		return -ENODEV;
565 
566 	/* Set up DEV_TYPE environment variable. */
567 	retval = add_uevent_var(env, "DEV_TYPE=%04X", ap_dev->device_type);
568 	if (retval)
569 		return retval;
570 
571 	/* Add MODALIAS= */
572 	retval = add_uevent_var(env, "MODALIAS=ap:t%02X", ap_dev->device_type);
573 
574 	return retval;
575 }
576 
577 static int __ap_queue_devices_with_id_unregister(struct device *dev, void *data)
578 {
579 	if (is_queue_dev(dev) &&
580 	    AP_QID_CARD(to_ap_queue(dev)->qid) == (int)(long) data)
581 		device_unregister(dev);
582 	return 0;
583 }
584 
585 static struct bus_type ap_bus_type = {
586 	.name = "ap",
587 	.match = &ap_bus_match,
588 	.uevent = &ap_uevent,
589 };
590 
591 static int __ap_revise_reserved(struct device *dev, void *dummy)
592 {
593 	int rc, card, queue, devres, drvres;
594 
595 	if (is_queue_dev(dev)) {
596 		card = AP_QID_CARD(to_ap_queue(dev)->qid);
597 		queue = AP_QID_QUEUE(to_ap_queue(dev)->qid);
598 		mutex_lock(&ap_perms_mutex);
599 		devres = test_bit_inv(card, ap_perms.apm)
600 			&& test_bit_inv(queue, ap_perms.aqm);
601 		mutex_unlock(&ap_perms_mutex);
602 		drvres = to_ap_drv(dev->driver)->flags
603 			& AP_DRIVER_FLAG_DEFAULT;
604 		if (!!devres != !!drvres) {
605 			AP_DBF(DBF_DEBUG, "reprobing queue=%02x.%04x\n",
606 			       card, queue);
607 			rc = device_reprobe(dev);
608 		}
609 	}
610 
611 	return 0;
612 }
613 
614 static void ap_bus_revise_bindings(void)
615 {
616 	bus_for_each_dev(&ap_bus_type, NULL, NULL, __ap_revise_reserved);
617 }
618 
619 int ap_owned_by_def_drv(int card, int queue)
620 {
621 	int rc = 0;
622 
623 	if (card < 0 || card >= AP_DEVICES || queue < 0 || queue >= AP_DOMAINS)
624 		return -EINVAL;
625 
626 	mutex_lock(&ap_perms_mutex);
627 
628 	if (test_bit_inv(card, ap_perms.apm)
629 	    && test_bit_inv(queue, ap_perms.aqm))
630 		rc = 1;
631 
632 	mutex_unlock(&ap_perms_mutex);
633 
634 	return rc;
635 }
636 EXPORT_SYMBOL(ap_owned_by_def_drv);
637 
638 int ap_apqn_in_matrix_owned_by_def_drv(unsigned long *apm,
639 				       unsigned long *aqm)
640 {
641 	int card, queue, rc = 0;
642 
643 	mutex_lock(&ap_perms_mutex);
644 
645 	for (card = 0; !rc && card < AP_DEVICES; card++)
646 		if (test_bit_inv(card, apm) &&
647 		    test_bit_inv(card, ap_perms.apm))
648 			for (queue = 0; !rc && queue < AP_DOMAINS; queue++)
649 				if (test_bit_inv(queue, aqm) &&
650 				    test_bit_inv(queue, ap_perms.aqm))
651 					rc = 1;
652 
653 	mutex_unlock(&ap_perms_mutex);
654 
655 	return rc;
656 }
657 EXPORT_SYMBOL(ap_apqn_in_matrix_owned_by_def_drv);
658 
659 static int ap_device_probe(struct device *dev)
660 {
661 	struct ap_device *ap_dev = to_ap_dev(dev);
662 	struct ap_driver *ap_drv = to_ap_drv(dev->driver);
663 	int card, queue, devres, drvres, rc;
664 
665 	if (is_queue_dev(dev)) {
666 		/*
667 		 * If the apqn is marked as reserved/used by ap bus and
668 		 * default drivers, only probe with drivers with the default
669 		 * flag set. If it is not marked, only probe with drivers
670 		 * with the default flag not set.
671 		 */
672 		card = AP_QID_CARD(to_ap_queue(dev)->qid);
673 		queue = AP_QID_QUEUE(to_ap_queue(dev)->qid);
674 		mutex_lock(&ap_perms_mutex);
675 		devres = test_bit_inv(card, ap_perms.apm)
676 			&& test_bit_inv(queue, ap_perms.aqm);
677 		mutex_unlock(&ap_perms_mutex);
678 		drvres = ap_drv->flags & AP_DRIVER_FLAG_DEFAULT;
679 		if (!!devres != !!drvres)
680 			return -ENODEV;
681 	}
682 
683 	/* Add queue/card to list of active queues/cards */
684 	spin_lock_bh(&ap_queues_lock);
685 	if (is_queue_dev(dev))
686 		hash_add(ap_queues, &to_ap_queue(dev)->hnode,
687 			 to_ap_queue(dev)->qid);
688 	spin_unlock_bh(&ap_queues_lock);
689 
690 	ap_dev->drv = ap_drv;
691 	rc = ap_drv->probe ? ap_drv->probe(ap_dev) : -ENODEV;
692 
693 	if (rc) {
694 		spin_lock_bh(&ap_queues_lock);
695 		if (is_queue_dev(dev))
696 			hash_del(&to_ap_queue(dev)->hnode);
697 		spin_unlock_bh(&ap_queues_lock);
698 		ap_dev->drv = NULL;
699 	}
700 
701 	return rc;
702 }
703 
704 static int ap_device_remove(struct device *dev)
705 {
706 	struct ap_device *ap_dev = to_ap_dev(dev);
707 	struct ap_driver *ap_drv = ap_dev->drv;
708 
709 	/* prepare ap queue device removal */
710 	if (is_queue_dev(dev))
711 		ap_queue_prepare_remove(to_ap_queue(dev));
712 
713 	/* driver's chance to clean up gracefully */
714 	if (ap_drv->remove)
715 		ap_drv->remove(ap_dev);
716 
717 	/* now do the ap queue device remove */
718 	if (is_queue_dev(dev))
719 		ap_queue_remove(to_ap_queue(dev));
720 
721 	/* Remove queue/card from list of active queues/cards */
722 	spin_lock_bh(&ap_queues_lock);
723 	if (is_queue_dev(dev))
724 		hash_del(&to_ap_queue(dev)->hnode);
725 	spin_unlock_bh(&ap_queues_lock);
726 
727 	return 0;
728 }
729 
730 struct ap_queue *ap_get_qdev(ap_qid_t qid)
731 {
732 	int bkt;
733 	struct ap_queue *aq;
734 
735 	spin_lock_bh(&ap_queues_lock);
736 	hash_for_each(ap_queues, bkt, aq, hnode) {
737 		if (aq->qid == qid) {
738 			get_device(&aq->ap_dev.device);
739 			spin_unlock_bh(&ap_queues_lock);
740 			return aq;
741 		}
742 	}
743 	spin_unlock_bh(&ap_queues_lock);
744 
745 	return NULL;
746 }
747 EXPORT_SYMBOL(ap_get_qdev);
748 
749 int ap_driver_register(struct ap_driver *ap_drv, struct module *owner,
750 		       char *name)
751 {
752 	struct device_driver *drv = &ap_drv->driver;
753 
754 	if (!initialised)
755 		return -ENODEV;
756 
757 	drv->bus = &ap_bus_type;
758 	drv->probe = ap_device_probe;
759 	drv->remove = ap_device_remove;
760 	drv->owner = owner;
761 	drv->name = name;
762 	return driver_register(drv);
763 }
764 EXPORT_SYMBOL(ap_driver_register);
765 
766 void ap_driver_unregister(struct ap_driver *ap_drv)
767 {
768 	driver_unregister(&ap_drv->driver);
769 }
770 EXPORT_SYMBOL(ap_driver_unregister);
771 
772 void ap_bus_force_rescan(void)
773 {
774 	/* processing a asynchronous bus rescan */
775 	del_timer(&ap_config_timer);
776 	queue_work(system_long_wq, &ap_scan_work);
777 	flush_work(&ap_scan_work);
778 }
779 EXPORT_SYMBOL(ap_bus_force_rescan);
780 
781 /*
782 * A config change has happened, force an ap bus rescan.
783 */
784 void ap_bus_cfg_chg(void)
785 {
786 	AP_DBF(DBF_INFO, "%s config change, forcing bus rescan\n", __func__);
787 
788 	ap_bus_force_rescan();
789 }
790 
791 /*
792  * hex2bitmap() - parse hex mask string and set bitmap.
793  * Valid strings are "0x012345678" with at least one valid hex number.
794  * Rest of the bitmap to the right is padded with 0. No spaces allowed
795  * within the string, the leading 0x may be omitted.
796  * Returns the bitmask with exactly the bits set as given by the hex
797  * string (both in big endian order).
798  */
799 static int hex2bitmap(const char *str, unsigned long *bitmap, int bits)
800 {
801 	int i, n, b;
802 
803 	/* bits needs to be a multiple of 8 */
804 	if (bits & 0x07)
805 		return -EINVAL;
806 
807 	if (str[0] == '0' && str[1] == 'x')
808 		str++;
809 	if (*str == 'x')
810 		str++;
811 
812 	for (i = 0; isxdigit(*str) && i < bits; str++) {
813 		b = hex_to_bin(*str);
814 		for (n = 0; n < 4; n++)
815 			if (b & (0x08 >> n))
816 				set_bit_inv(i + n, bitmap);
817 		i += 4;
818 	}
819 
820 	if (*str == '\n')
821 		str++;
822 	if (*str)
823 		return -EINVAL;
824 	return 0;
825 }
826 
827 /*
828  * modify_bitmap() - parse bitmask argument and modify an existing
829  * bit mask accordingly. A concatenation (done with ',') of these
830  * terms is recognized:
831  *   +<bitnr>[-<bitnr>] or -<bitnr>[-<bitnr>]
832  * <bitnr> may be any valid number (hex, decimal or octal) in the range
833  * 0...bits-1; the leading + or - is required. Here are some examples:
834  *   +0-15,+32,-128,-0xFF
835  *   -0-255,+1-16,+0x128
836  *   +1,+2,+3,+4,-5,-7-10
837  * Returns the new bitmap after all changes have been applied. Every
838  * positive value in the string will set a bit and every negative value
839  * in the string will clear a bit. As a bit may be touched more than once,
840  * the last 'operation' wins:
841  * +0-255,-128 = first bits 0-255 will be set, then bit 128 will be
842  * cleared again. All other bits are unmodified.
843  */
844 static int modify_bitmap(const char *str, unsigned long *bitmap, int bits)
845 {
846 	int a, i, z;
847 	char *np, sign;
848 
849 	/* bits needs to be a multiple of 8 */
850 	if (bits & 0x07)
851 		return -EINVAL;
852 
853 	while (*str) {
854 		sign = *str++;
855 		if (sign != '+' && sign != '-')
856 			return -EINVAL;
857 		a = z = simple_strtoul(str, &np, 0);
858 		if (str == np || a >= bits)
859 			return -EINVAL;
860 		str = np;
861 		if (*str == '-') {
862 			z = simple_strtoul(++str, &np, 0);
863 			if (str == np || a > z || z >= bits)
864 				return -EINVAL;
865 			str = np;
866 		}
867 		for (i = a; i <= z; i++)
868 			if (sign == '+')
869 				set_bit_inv(i, bitmap);
870 			else
871 				clear_bit_inv(i, bitmap);
872 		while (*str == ',' || *str == '\n')
873 			str++;
874 	}
875 
876 	return 0;
877 }
878 
879 int ap_parse_mask_str(const char *str,
880 		      unsigned long *bitmap, int bits,
881 		      struct mutex *lock)
882 {
883 	unsigned long *newmap, size;
884 	int rc;
885 
886 	/* bits needs to be a multiple of 8 */
887 	if (bits & 0x07)
888 		return -EINVAL;
889 
890 	size = BITS_TO_LONGS(bits)*sizeof(unsigned long);
891 	newmap = kmalloc(size, GFP_KERNEL);
892 	if (!newmap)
893 		return -ENOMEM;
894 	if (mutex_lock_interruptible(lock)) {
895 		kfree(newmap);
896 		return -ERESTARTSYS;
897 	}
898 
899 	if (*str == '+' || *str == '-') {
900 		memcpy(newmap, bitmap, size);
901 		rc = modify_bitmap(str, newmap, bits);
902 	} else {
903 		memset(newmap, 0, size);
904 		rc = hex2bitmap(str, newmap, bits);
905 	}
906 	if (rc == 0)
907 		memcpy(bitmap, newmap, size);
908 	mutex_unlock(lock);
909 	kfree(newmap);
910 	return rc;
911 }
912 EXPORT_SYMBOL(ap_parse_mask_str);
913 
914 /*
915  * AP bus attributes.
916  */
917 
918 static ssize_t ap_domain_show(struct bus_type *bus, char *buf)
919 {
920 	return scnprintf(buf, PAGE_SIZE, "%d\n", ap_domain_index);
921 }
922 
923 static ssize_t ap_domain_store(struct bus_type *bus,
924 			       const char *buf, size_t count)
925 {
926 	int domain;
927 
928 	if (sscanf(buf, "%i\n", &domain) != 1 ||
929 	    domain < 0 || domain > ap_max_domain_id ||
930 	    !test_bit_inv(domain, ap_perms.aqm))
931 		return -EINVAL;
932 	spin_lock_bh(&ap_domain_lock);
933 	ap_domain_index = domain;
934 	spin_unlock_bh(&ap_domain_lock);
935 
936 	AP_DBF(DBF_DEBUG, "stored new default domain=%d\n", domain);
937 
938 	return count;
939 }
940 
941 static BUS_ATTR_RW(ap_domain);
942 
943 static ssize_t ap_control_domain_mask_show(struct bus_type *bus, char *buf)
944 {
945 	if (!ap_configuration)	/* QCI not supported */
946 		return scnprintf(buf, PAGE_SIZE, "not supported\n");
947 
948 	return scnprintf(buf, PAGE_SIZE,
949 			 "0x%08x%08x%08x%08x%08x%08x%08x%08x\n",
950 			 ap_configuration->adm[0], ap_configuration->adm[1],
951 			 ap_configuration->adm[2], ap_configuration->adm[3],
952 			 ap_configuration->adm[4], ap_configuration->adm[5],
953 			 ap_configuration->adm[6], ap_configuration->adm[7]);
954 }
955 
956 static BUS_ATTR_RO(ap_control_domain_mask);
957 
958 static ssize_t ap_usage_domain_mask_show(struct bus_type *bus, char *buf)
959 {
960 	if (!ap_configuration)	/* QCI not supported */
961 		return scnprintf(buf, PAGE_SIZE, "not supported\n");
962 
963 	return scnprintf(buf, PAGE_SIZE,
964 			 "0x%08x%08x%08x%08x%08x%08x%08x%08x\n",
965 			 ap_configuration->aqm[0], ap_configuration->aqm[1],
966 			 ap_configuration->aqm[2], ap_configuration->aqm[3],
967 			 ap_configuration->aqm[4], ap_configuration->aqm[5],
968 			 ap_configuration->aqm[6], ap_configuration->aqm[7]);
969 }
970 
971 static BUS_ATTR_RO(ap_usage_domain_mask);
972 
973 static ssize_t ap_adapter_mask_show(struct bus_type *bus, char *buf)
974 {
975 	if (!ap_configuration)	/* QCI not supported */
976 		return scnprintf(buf, PAGE_SIZE, "not supported\n");
977 
978 	return scnprintf(buf, PAGE_SIZE,
979 			 "0x%08x%08x%08x%08x%08x%08x%08x%08x\n",
980 			 ap_configuration->apm[0], ap_configuration->apm[1],
981 			 ap_configuration->apm[2], ap_configuration->apm[3],
982 			 ap_configuration->apm[4], ap_configuration->apm[5],
983 			 ap_configuration->apm[6], ap_configuration->apm[7]);
984 }
985 
986 static BUS_ATTR_RO(ap_adapter_mask);
987 
988 static ssize_t ap_interrupts_show(struct bus_type *bus, char *buf)
989 {
990 	return scnprintf(buf, PAGE_SIZE, "%d\n",
991 			 ap_using_interrupts() ? 1 : 0);
992 }
993 
994 static BUS_ATTR_RO(ap_interrupts);
995 
996 static ssize_t config_time_show(struct bus_type *bus, char *buf)
997 {
998 	return scnprintf(buf, PAGE_SIZE, "%d\n", ap_config_time);
999 }
1000 
1001 static ssize_t config_time_store(struct bus_type *bus,
1002 				 const char *buf, size_t count)
1003 {
1004 	int time;
1005 
1006 	if (sscanf(buf, "%d\n", &time) != 1 || time < 5 || time > 120)
1007 		return -EINVAL;
1008 	ap_config_time = time;
1009 	mod_timer(&ap_config_timer, jiffies + ap_config_time * HZ);
1010 	return count;
1011 }
1012 
1013 static BUS_ATTR_RW(config_time);
1014 
1015 static ssize_t poll_thread_show(struct bus_type *bus, char *buf)
1016 {
1017 	return scnprintf(buf, PAGE_SIZE, "%d\n", ap_poll_kthread ? 1 : 0);
1018 }
1019 
1020 static ssize_t poll_thread_store(struct bus_type *bus,
1021 				 const char *buf, size_t count)
1022 {
1023 	int flag, rc;
1024 
1025 	if (sscanf(buf, "%d\n", &flag) != 1)
1026 		return -EINVAL;
1027 	if (flag) {
1028 		rc = ap_poll_thread_start();
1029 		if (rc)
1030 			count = rc;
1031 	} else
1032 		ap_poll_thread_stop();
1033 	return count;
1034 }
1035 
1036 static BUS_ATTR_RW(poll_thread);
1037 
1038 static ssize_t poll_timeout_show(struct bus_type *bus, char *buf)
1039 {
1040 	return scnprintf(buf, PAGE_SIZE, "%llu\n", poll_timeout);
1041 }
1042 
1043 static ssize_t poll_timeout_store(struct bus_type *bus, const char *buf,
1044 				  size_t count)
1045 {
1046 	unsigned long long time;
1047 	ktime_t hr_time;
1048 
1049 	/* 120 seconds = maximum poll interval */
1050 	if (sscanf(buf, "%llu\n", &time) != 1 || time < 1 ||
1051 	    time > 120000000000ULL)
1052 		return -EINVAL;
1053 	poll_timeout = time;
1054 	hr_time = poll_timeout;
1055 
1056 	spin_lock_bh(&ap_poll_timer_lock);
1057 	hrtimer_cancel(&ap_poll_timer);
1058 	hrtimer_set_expires(&ap_poll_timer, hr_time);
1059 	hrtimer_start_expires(&ap_poll_timer, HRTIMER_MODE_ABS);
1060 	spin_unlock_bh(&ap_poll_timer_lock);
1061 
1062 	return count;
1063 }
1064 
1065 static BUS_ATTR_RW(poll_timeout);
1066 
1067 static ssize_t ap_max_domain_id_show(struct bus_type *bus, char *buf)
1068 {
1069 	int max_domain_id;
1070 
1071 	if (ap_configuration)
1072 		max_domain_id = ap_max_domain_id ? : -1;
1073 	else
1074 		max_domain_id = 15;
1075 	return scnprintf(buf, PAGE_SIZE, "%d\n", max_domain_id);
1076 }
1077 
1078 static BUS_ATTR_RO(ap_max_domain_id);
1079 
1080 static ssize_t apmask_show(struct bus_type *bus, char *buf)
1081 {
1082 	int rc;
1083 
1084 	if (mutex_lock_interruptible(&ap_perms_mutex))
1085 		return -ERESTARTSYS;
1086 	rc = scnprintf(buf, PAGE_SIZE,
1087 		       "0x%016lx%016lx%016lx%016lx\n",
1088 		       ap_perms.apm[0], ap_perms.apm[1],
1089 		       ap_perms.apm[2], ap_perms.apm[3]);
1090 	mutex_unlock(&ap_perms_mutex);
1091 
1092 	return rc;
1093 }
1094 
1095 static ssize_t apmask_store(struct bus_type *bus, const char *buf,
1096 			    size_t count)
1097 {
1098 	int rc;
1099 
1100 	rc = ap_parse_mask_str(buf, ap_perms.apm, AP_DEVICES, &ap_perms_mutex);
1101 	if (rc)
1102 		return rc;
1103 
1104 	ap_bus_revise_bindings();
1105 
1106 	return count;
1107 }
1108 
1109 static BUS_ATTR_RW(apmask);
1110 
1111 static ssize_t aqmask_show(struct bus_type *bus, char *buf)
1112 {
1113 	int rc;
1114 
1115 	if (mutex_lock_interruptible(&ap_perms_mutex))
1116 		return -ERESTARTSYS;
1117 	rc = scnprintf(buf, PAGE_SIZE,
1118 		       "0x%016lx%016lx%016lx%016lx\n",
1119 		       ap_perms.aqm[0], ap_perms.aqm[1],
1120 		       ap_perms.aqm[2], ap_perms.aqm[3]);
1121 	mutex_unlock(&ap_perms_mutex);
1122 
1123 	return rc;
1124 }
1125 
1126 static ssize_t aqmask_store(struct bus_type *bus, const char *buf,
1127 			    size_t count)
1128 {
1129 	int rc;
1130 
1131 	rc = ap_parse_mask_str(buf, ap_perms.aqm, AP_DOMAINS, &ap_perms_mutex);
1132 	if (rc)
1133 		return rc;
1134 
1135 	ap_bus_revise_bindings();
1136 
1137 	return count;
1138 }
1139 
1140 static BUS_ATTR_RW(aqmask);
1141 
1142 static struct bus_attribute *const ap_bus_attrs[] = {
1143 	&bus_attr_ap_domain,
1144 	&bus_attr_ap_control_domain_mask,
1145 	&bus_attr_ap_usage_domain_mask,
1146 	&bus_attr_ap_adapter_mask,
1147 	&bus_attr_config_time,
1148 	&bus_attr_poll_thread,
1149 	&bus_attr_ap_interrupts,
1150 	&bus_attr_poll_timeout,
1151 	&bus_attr_ap_max_domain_id,
1152 	&bus_attr_apmask,
1153 	&bus_attr_aqmask,
1154 	NULL,
1155 };
1156 
1157 /**
1158  * ap_select_domain(): Select an AP domain if possible and we haven't
1159  * already done so before.
1160  */
1161 static void ap_select_domain(void)
1162 {
1163 	int count, max_count, best_domain;
1164 	struct ap_queue_status status;
1165 	int i, j;
1166 
1167 	/*
1168 	 * We want to use a single domain. Either the one specified with
1169 	 * the "domain=" parameter or the domain with the maximum number
1170 	 * of devices.
1171 	 */
1172 	spin_lock_bh(&ap_domain_lock);
1173 	if (ap_domain_index >= 0) {
1174 		/* Domain has already been selected. */
1175 		spin_unlock_bh(&ap_domain_lock);
1176 		return;
1177 	}
1178 	best_domain = -1;
1179 	max_count = 0;
1180 	for (i = 0; i < AP_DOMAINS; i++) {
1181 		if (!ap_test_config_usage_domain(i) ||
1182 		    !test_bit_inv(i, ap_perms.aqm))
1183 			continue;
1184 		count = 0;
1185 		for (j = 0; j < AP_DEVICES; j++) {
1186 			if (!ap_test_config_card_id(j))
1187 				continue;
1188 			status = ap_test_queue(AP_MKQID(j, i),
1189 					       ap_apft_available(),
1190 					       NULL);
1191 			if (status.response_code != AP_RESPONSE_NORMAL)
1192 				continue;
1193 			count++;
1194 		}
1195 		if (count > max_count) {
1196 			max_count = count;
1197 			best_domain = i;
1198 		}
1199 	}
1200 	if (best_domain >= 0) {
1201 		ap_domain_index = best_domain;
1202 		AP_DBF(DBF_DEBUG, "new ap_domain_index=%d\n", ap_domain_index);
1203 	}
1204 	spin_unlock_bh(&ap_domain_lock);
1205 }
1206 
1207 /*
1208  * This function checks the type and returns either 0 for not
1209  * supported or the highest compatible type value (which may
1210  * include the input type value).
1211  */
1212 static int ap_get_compatible_type(ap_qid_t qid, int rawtype, unsigned int func)
1213 {
1214 	int comp_type = 0;
1215 
1216 	/* < CEX2A is not supported */
1217 	if (rawtype < AP_DEVICE_TYPE_CEX2A)
1218 		return 0;
1219 	/* up to CEX7 known and fully supported */
1220 	if (rawtype <= AP_DEVICE_TYPE_CEX7)
1221 		return rawtype;
1222 	/*
1223 	 * unknown new type > CEX7, check for compatibility
1224 	 * to the highest known and supported type which is
1225 	 * currently CEX7 with the help of the QACT function.
1226 	 */
1227 	if (ap_qact_available()) {
1228 		struct ap_queue_status status;
1229 		union ap_qact_ap_info apinfo = {0};
1230 
1231 		apinfo.mode = (func >> 26) & 0x07;
1232 		apinfo.cat = AP_DEVICE_TYPE_CEX7;
1233 		status = ap_qact(qid, 0, &apinfo);
1234 		if (status.response_code == AP_RESPONSE_NORMAL
1235 		    && apinfo.cat >= AP_DEVICE_TYPE_CEX2A
1236 		    && apinfo.cat <= AP_DEVICE_TYPE_CEX7)
1237 			comp_type = apinfo.cat;
1238 	}
1239 	if (!comp_type)
1240 		AP_DBF(DBF_WARN, "queue=%02x.%04x unable to map type %d\n",
1241 		       AP_QID_CARD(qid), AP_QID_QUEUE(qid), rawtype);
1242 	else if (comp_type != rawtype)
1243 		AP_DBF(DBF_INFO, "queue=%02x.%04x map type %d to %d\n",
1244 		       AP_QID_CARD(qid), AP_QID_QUEUE(qid), rawtype, comp_type);
1245 	return comp_type;
1246 }
1247 
1248 /*
1249  * Helper function to be used with bus_find_dev
1250  * matches for the card device with the given id
1251  */
1252 static int __match_card_device_with_id(struct device *dev, const void *data)
1253 {
1254 	return is_card_dev(dev) && to_ap_card(dev)->id == (int)(long)(void *) data;
1255 }
1256 
1257 /*
1258  * Helper function to be used with bus_find_dev
1259  * matches for the queue device with a given qid
1260  */
1261 static int __match_queue_device_with_qid(struct device *dev, const void *data)
1262 {
1263 	return is_queue_dev(dev) && to_ap_queue(dev)->qid == (int)(long) data;
1264 }
1265 
1266 /*
1267  * Helper function to be used with bus_find_dev
1268  * matches any queue device with given queue id
1269  */
1270 static int __match_queue_device_with_queue_id(struct device *dev, const void *data)
1271 {
1272 	return is_queue_dev(dev)
1273 		&& AP_QID_QUEUE(to_ap_queue(dev)->qid) == (int)(long) data;
1274 }
1275 
1276 /*
1277  * Helper function for ap_scan_bus().
1278  * Does the scan bus job for the given adapter id.
1279  */
1280 static void _ap_scan_bus_adapter(int id)
1281 {
1282 	ap_qid_t qid;
1283 	unsigned int func;
1284 	struct ap_card *ac;
1285 	struct device *dev;
1286 	struct ap_queue *aq;
1287 	int rc, dom, depth, type, comp_type, borked;
1288 
1289 	/* check if there is a card device registered with this id */
1290 	dev = bus_find_device(&ap_bus_type, NULL,
1291 			      (void *)(long) id,
1292 			      __match_card_device_with_id);
1293 	ac = dev ? to_ap_card(dev) : NULL;
1294 	if (!ap_test_config_card_id(id)) {
1295 		if (dev) {
1296 			/* Card device has been removed from configuration */
1297 			bus_for_each_dev(&ap_bus_type, NULL,
1298 					 (void *)(long) id,
1299 					 __ap_queue_devices_with_id_unregister);
1300 			device_unregister(dev);
1301 			put_device(dev);
1302 		}
1303 		return;
1304 	}
1305 
1306 	/*
1307 	 * This card id is enabled in the configuration. If we already have
1308 	 * a card device with this id, check if type and functions are still
1309 	 * the very same. Also verify that at least one queue is available.
1310 	 */
1311 	if (ac) {
1312 		/* find the first valid queue */
1313 		for (dom = 0; dom < AP_DOMAINS; dom++) {
1314 			qid = AP_MKQID(id, dom);
1315 			if (ap_query_queue(qid, &depth, &type, &func) == 0)
1316 				break;
1317 		}
1318 		borked = 0;
1319 		if (dom >= AP_DOMAINS) {
1320 			/* no accessible queue on this card */
1321 			borked = 1;
1322 		} else if (ac->raw_hwtype != type) {
1323 			/* card type has changed */
1324 			AP_DBF(DBF_INFO, "card=%02x type changed.\n", id);
1325 			borked = 1;
1326 		} else if (ac->functions != func) {
1327 			/* card functions have changed */
1328 			AP_DBF(DBF_INFO, "card=%02x functions changed.\n", id);
1329 			borked = 1;
1330 		}
1331 		if (borked) {
1332 			/* unregister card device and associated queues */
1333 			bus_for_each_dev(&ap_bus_type, NULL,
1334 					 (void *)(long) id,
1335 					 __ap_queue_devices_with_id_unregister);
1336 			device_unregister(dev);
1337 			put_device(dev);
1338 			/* go back if there is no valid queue on this card */
1339 			if (dom >= AP_DOMAINS)
1340 				return;
1341 			ac = NULL;
1342 		}
1343 	}
1344 
1345 	/*
1346 	 * Go through all possible queue ids. Check and maybe create or release
1347 	 * queue devices for this card. If there exists no card device yet,
1348 	 * create a card device also.
1349 	 */
1350 	for (dom = 0; dom < AP_DOMAINS; dom++) {
1351 		qid = AP_MKQID(id, dom);
1352 		dev = bus_find_device(&ap_bus_type, NULL,
1353 				      (void *)(long) qid,
1354 				      __match_queue_device_with_qid);
1355 		aq = dev ? to_ap_queue(dev) : NULL;
1356 		if (!ap_test_config_usage_domain(dom)) {
1357 			if (dev) {
1358 				/* Queue device exists but has been
1359 				 * removed from configuration.
1360 				 */
1361 				device_unregister(dev);
1362 				put_device(dev);
1363 			}
1364 			continue;
1365 		}
1366 		/* try to fetch infos about this queue */
1367 		rc = ap_query_queue(qid, &depth, &type, &func);
1368 		if (dev) {
1369 			if (rc == -ENODEV)
1370 				borked = 1;
1371 			else {
1372 				spin_lock_bh(&aq->lock);
1373 				borked = aq->state == AP_STATE_BORKED;
1374 				spin_unlock_bh(&aq->lock);
1375 			}
1376 			if (borked) {
1377 				/* Remove broken device */
1378 				AP_DBF(DBF_DEBUG,
1379 				       "removing broken queue=%02x.%04x\n",
1380 				       id, dom);
1381 				device_unregister(dev);
1382 			}
1383 			put_device(dev);
1384 			continue;
1385 		}
1386 		if (rc)
1387 			continue;
1388 		/* a new queue device is needed, check out comp type */
1389 		comp_type = ap_get_compatible_type(qid, type, func);
1390 		if (!comp_type)
1391 			continue;
1392 		/* maybe a card device needs to be created first */
1393 		if (!ac) {
1394 			ac = ap_card_create(id, depth, type, comp_type, func);
1395 			if (!ac)
1396 				continue;
1397 			ac->ap_dev.device.bus = &ap_bus_type;
1398 			ac->ap_dev.device.parent = ap_root_device;
1399 			dev_set_name(&ac->ap_dev.device, "card%02x", id);
1400 			/* Register card device with AP bus */
1401 			rc = device_register(&ac->ap_dev.device);
1402 			if (rc) {
1403 				put_device(&ac->ap_dev.device);
1404 				ac = NULL;
1405 				break;
1406 			}
1407 			/* get it and thus adjust reference counter */
1408 			get_device(&ac->ap_dev.device);
1409 		}
1410 		/* now create the new queue device */
1411 		aq = ap_queue_create(qid, comp_type);
1412 		if (!aq)
1413 			continue;
1414 		aq->card = ac;
1415 		aq->ap_dev.device.bus = &ap_bus_type;
1416 		aq->ap_dev.device.parent = &ac->ap_dev.device;
1417 		dev_set_name(&aq->ap_dev.device, "%02x.%04x", id, dom);
1418 		/* Register queue device */
1419 		rc = device_register(&aq->ap_dev.device);
1420 		if (rc) {
1421 			put_device(&aq->ap_dev.device);
1422 			continue;
1423 		}
1424 	} /* end domain loop */
1425 
1426 	if (ac)
1427 		put_device(&ac->ap_dev.device);
1428 }
1429 
1430 /**
1431  * ap_scan_bus(): Scan the AP bus for new devices
1432  * Runs periodically, workqueue timer (ap_config_time)
1433  */
1434 static void ap_scan_bus(struct work_struct *unused)
1435 {
1436 	int id;
1437 
1438 	AP_DBF(DBF_DEBUG, "%s running\n", __func__);
1439 
1440 	ap_query_configuration(ap_configuration);
1441 	ap_select_domain();
1442 
1443 	/* loop over all possible adapters */
1444 	for (id = 0; id < AP_DEVICES; id++)
1445 		_ap_scan_bus_adapter(id);
1446 
1447 	/* check if there is at least one queue available with default domain */
1448 	if (ap_domain_index >= 0) {
1449 		struct device *dev =
1450 			bus_find_device(&ap_bus_type, NULL,
1451 					(void *)(long) ap_domain_index,
1452 					__match_queue_device_with_queue_id);
1453 		if (dev)
1454 			put_device(dev);
1455 		else
1456 			AP_DBF(DBF_INFO,
1457 			       "no queue device with default domain %d available\n",
1458 			       ap_domain_index);
1459 	}
1460 
1461 	mod_timer(&ap_config_timer, jiffies + ap_config_time * HZ);
1462 }
1463 
1464 static void ap_config_timeout(struct timer_list *unused)
1465 {
1466 	queue_work(system_long_wq, &ap_scan_work);
1467 }
1468 
1469 static int __init ap_debug_init(void)
1470 {
1471 	ap_dbf_info = debug_register("ap", 1, 1,
1472 				     DBF_MAX_SPRINTF_ARGS * sizeof(long));
1473 	debug_register_view(ap_dbf_info, &debug_sprintf_view);
1474 	debug_set_level(ap_dbf_info, DBF_ERR);
1475 
1476 	return 0;
1477 }
1478 
1479 static void __init ap_perms_init(void)
1480 {
1481 	/* all resources useable if no kernel parameter string given */
1482 	memset(&ap_perms.ioctlm, 0xFF, sizeof(ap_perms.ioctlm));
1483 	memset(&ap_perms.apm, 0xFF, sizeof(ap_perms.apm));
1484 	memset(&ap_perms.aqm, 0xFF, sizeof(ap_perms.aqm));
1485 
1486 	/* apm kernel parameter string */
1487 	if (apm_str) {
1488 		memset(&ap_perms.apm, 0, sizeof(ap_perms.apm));
1489 		ap_parse_mask_str(apm_str, ap_perms.apm, AP_DEVICES,
1490 				  &ap_perms_mutex);
1491 	}
1492 
1493 	/* aqm kernel parameter string */
1494 	if (aqm_str) {
1495 		memset(&ap_perms.aqm, 0, sizeof(ap_perms.aqm));
1496 		ap_parse_mask_str(aqm_str, ap_perms.aqm, AP_DOMAINS,
1497 				  &ap_perms_mutex);
1498 	}
1499 }
1500 
1501 /**
1502  * ap_module_init(): The module initialization code.
1503  *
1504  * Initializes the module.
1505  */
1506 static int __init ap_module_init(void)
1507 {
1508 	int max_domain_id;
1509 	int rc, i;
1510 
1511 	rc = ap_debug_init();
1512 	if (rc)
1513 		return rc;
1514 
1515 	if (!ap_instructions_available()) {
1516 		pr_warn("The hardware system does not support AP instructions\n");
1517 		return -ENODEV;
1518 	}
1519 
1520 	/* init ap_queue hashtable */
1521 	hash_init(ap_queues);
1522 
1523 	/* set up the AP permissions (ioctls, ap and aq masks) */
1524 	ap_perms_init();
1525 
1526 	/* Get AP configuration data if available */
1527 	ap_init_configuration();
1528 
1529 	if (ap_configuration)
1530 		max_domain_id =
1531 			ap_max_domain_id ? ap_max_domain_id : AP_DOMAINS - 1;
1532 	else
1533 		max_domain_id = 15;
1534 	if (ap_domain_index < -1 || ap_domain_index > max_domain_id ||
1535 	    (ap_domain_index >= 0 &&
1536 	     !test_bit_inv(ap_domain_index, ap_perms.aqm))) {
1537 		pr_warn("%d is not a valid cryptographic domain\n",
1538 			ap_domain_index);
1539 		ap_domain_index = -1;
1540 	}
1541 
1542 	if (ap_interrupts_available()) {
1543 		rc = register_adapter_interrupt(&ap_airq);
1544 		ap_airq_flag = (rc == 0);
1545 	}
1546 
1547 	/* Create /sys/bus/ap. */
1548 	rc = bus_register(&ap_bus_type);
1549 	if (rc)
1550 		goto out;
1551 	for (i = 0; ap_bus_attrs[i]; i++) {
1552 		rc = bus_create_file(&ap_bus_type, ap_bus_attrs[i]);
1553 		if (rc)
1554 			goto out_bus;
1555 	}
1556 
1557 	/* Create /sys/devices/ap. */
1558 	ap_root_device = root_device_register("ap");
1559 	rc = PTR_ERR_OR_ZERO(ap_root_device);
1560 	if (rc)
1561 		goto out_bus;
1562 
1563 	/* Setup the AP bus rescan timer. */
1564 	timer_setup(&ap_config_timer, ap_config_timeout, 0);
1565 
1566 	/*
1567 	 * Setup the high resultion poll timer.
1568 	 * If we are running under z/VM adjust polling to z/VM polling rate.
1569 	 */
1570 	if (MACHINE_IS_VM)
1571 		poll_timeout = 1500000;
1572 	spin_lock_init(&ap_poll_timer_lock);
1573 	hrtimer_init(&ap_poll_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
1574 	ap_poll_timer.function = ap_poll_timeout;
1575 
1576 	/* Start the low priority AP bus poll thread. */
1577 	if (ap_thread_flag) {
1578 		rc = ap_poll_thread_start();
1579 		if (rc)
1580 			goto out_work;
1581 	}
1582 
1583 	queue_work(system_long_wq, &ap_scan_work);
1584 	initialised = true;
1585 
1586 	return 0;
1587 
1588 out_work:
1589 	hrtimer_cancel(&ap_poll_timer);
1590 	root_device_unregister(ap_root_device);
1591 out_bus:
1592 	while (i--)
1593 		bus_remove_file(&ap_bus_type, ap_bus_attrs[i]);
1594 	bus_unregister(&ap_bus_type);
1595 out:
1596 	if (ap_using_interrupts())
1597 		unregister_adapter_interrupt(&ap_airq);
1598 	kfree(ap_configuration);
1599 	return rc;
1600 }
1601 device_initcall(ap_module_init);
1602